U.S. patent application number 15/835007 was filed with the patent office on 2018-04-05 for wireless handheld devices, radiation systems and manufacturing methods.
The applicant listed for this patent is Fractus Antennas, S.L.. Invention is credited to Aurora Andujar Linares, Jaume Anguera Pros, Carles Puente Baliarda.
Application Number | 20180097278 15/835007 |
Document ID | / |
Family ID | 49913540 |
Filed Date | 2018-04-05 |
United States Patent
Application |
20180097278 |
Kind Code |
A1 |
Anguera Pros; Jaume ; et
al. |
April 5, 2018 |
Wireless Handheld Devices, Radiation Systems and Manufacturing
Methods
Abstract
A radiating system for transmitting and receiving signals in
first and second frequency regions includes a radiating structure,
a radiofrequency system, and an external port. The radiating
structure has first and second isolated radiation boosters coupled
to a ground plane layer. A first internal port of the radiating
structure is between the first radiation booster and the ground
plane layer, and a second internal port is between the second
radiation booster and the ground plane layer. A distance between
the two internal ports is less than 0.06 times a wavelength of the
lowest frequency. The maximum size of the first and second
radiation boosters is smaller than 1/30 times the wavelength of the
lowest frequency. The radiofrequency system includes two ports
connected respectively to the first and the second internal ports
of the radiating structure, and a port connected to the external
port of the radiating system.
Inventors: |
Anguera Pros; Jaume;
(Vinaros, ES) ; Andujar Linares; Aurora;
(Barcelona, ES) ; Puente Baliarda; Carles;
(Barcelona, ES) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Fractus Antennas, S.L. |
Sant Cugat del Valles |
|
ES |
|
|
Family ID: |
49913540 |
Appl. No.: |
15/835007 |
Filed: |
December 7, 2017 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
15093513 |
Apr 7, 2016 |
9865917 |
|
|
15835007 |
|
|
|
|
13946922 |
Jul 19, 2013 |
9331389 |
|
|
15093513 |
|
|
|
|
13803100 |
Mar 14, 2013 |
9379443 |
|
|
13946922 |
|
|
|
|
61671906 |
Jul 16, 2012 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01Q 1/2283 20130101;
H01Q 9/0414 20130101; H01Q 1/36 20130101; H01Q 1/243 20130101; H01Q
9/0421 20130101; H01Q 9/06 20130101 |
International
Class: |
H01Q 1/24 20060101
H01Q001/24; H01Q 9/04 20060101 H01Q009/04; H01Q 1/22 20060101
H01Q001/22; H01Q 9/06 20060101 H01Q009/06; H01Q 1/36 20060101
H01Q001/36 |
Claims
1. A radiation booster for enabling a radiating structure to
transmit and receive electromagnetic wave signals in a frequency
region, the radiation booster comprising: a dielectric element
comprising a substantially polyhedral form factor; a first
conductive element disposed on a first face of the dielectric
element; a second conductive element disposed on a second face of
the dielectric element; and a third conductive element disposed in
at least one via hole through the dielectric element and connecting
the first and second conductive elements.
2. The radiation booster of claim 1, wherein a longest edge of the
radiation booster is shorter than 1/30 of a longest operating
wavelength of a lowest operating frequency band at which the
radiation booster operates.
3. The radiation booster of claim 1, wherein the dielectric element
comprises a substantially cuboid shape.
4. The radiation booster of claim 1, wherein the dielectric element
comprises a substantially parallelepiped shape.
5. The radiation booster of claim 1, wherein the dielectric element
comprises a substantially cube shape.
6. The radiation booster of claim 1, wherein the first conductive
element is printed on the first face of the dielectric element; the
second conductive element is printed on the second face of the
dielectric element; and the first and second conductive elements
are substantially parallel to each other.
7. The radiation booster of claim 1, wherein the third conductive
element is disposed in at least two via holes through the
dielectric element.
8. The radiation booster of claim 1, wherein the third conductive
element is disposed in four via holes through the dielectric
element, each of the four via holes terminating at one end at the
first face of the dielectric element near a respective corner of
the first face and terminating at another end at the second face of
the dielectric element near a respective corner of the second
face.
9. The radiation booster of claim 1, wherein the third conductive
element is disposed in a single via hole through the dielectric
element, the via hole terminating at one end at the first face of
the dielectric element near a center of the first face and
terminating at another end at the second face of the dielectric
element near a center of the second face.
10. The radiation booster of claim 1, wherein the third conductive
element is disposed in a single via hole through the dielectric
element, the via hole terminating at one end at the first face of
the dielectric element near a corner of the first face and
terminating at another end at the second face of the dielectric
element near a corresponding corner of the second face.
11. The radiation booster of claim 1, wherein the third conductive
element is disposed in at least first and second via holes through
the dielectric element, the first via hole holes terminating at one
end at the first face of the dielectric element near a first corner
of the first face and terminating at another end at the second face
of the dielectric element near a corresponding first corner of the
second face, the second via hole holes terminating at one end at
the first face of the dielectric element near a second corner of
the first face, the second corner of the first face being opposite
the first corner of the first face, and terminating at another end
at the second face of the dielectric element near a corresponding
second corner of the second face, the second corner of the second
face being opposite the first corner of the second face.
12. The radiation booster of claim 1, wherein the first conductive
element comprises a space filling curve comprising at least ten
segments.
13. The radiation booster of claim 1, wherein a thickness of the
dielectric element between the first and second faces is less than
one-fifth of a length of a shorter side of a minimum quadrilateral
that encloses either the first conductive element or the second
conductive element.
14. The radiation booster of claim 1, wherein a thickness of the
dielectric element between the first and second faces is 5 mm or
less.
15. The radiation booster of claim 1, wherein the frequency region
includes the 824-960 MHz frequency range.
16. The radiation booster of claim 15, wherein the radiation
booster is configured to operate at a second frequency region that
includes the 1,710-1,890 MHz frequency range.
17. The radiation booster of claim 1, wherein the frequency region
includes the LTE frequency band.
18. The radiation booster of claim 17, wherein the LTE frequency
band includes the 700 MHz frequency.
19. A radiation booster apparatus for enabling a radiating
structure to transmit and receive electromagnetic wave signals in a
frequency region, the radiation booster comprising: a unitary
dielectric element comprising a substantially polyhedral form
factor; a first radiation booster comprising: a first conductive
element disposed on a first portion of a first face of the
dielectric element; a second conductive element disposed on a first
portion of a second face of the dielectric element; and a third
conductive element disposed in at least one via hole through the
dielectric element and connecting the first and second conductive
elements; and a second radiation booster comprising: a fourth
conductive element disposed on a second portion of the first face
of the dielectric element; a fifth conductive element disposed on a
second portion of the second face of the dielectric element; and a
sixth conductive element disposed in at least one via hole through
the dielectric element and connecting the fourth and fifth
conductive elements.
20. A radiation booster for enabling a radiating structure to
transmit and receive electromagnetic wave signals in a frequency
region, the radiation booster comprising: a dielectric element
comprising a substantially polyhedral form factor; a first
conductive element disposed on a first face of the dielectric
element; a second conductive element disposed on a second face of
the dielectric element; and a third conductive element comprising a
conductive strip disposed on a third face of the dielectric element
and connecting the first and second conductive elements.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 15/093,513 filed Apr. 7, 2016, which is a
continuation of U.S. patent application Ser. No. 13/946,922 filed
Jul. 19, 2013, which is now U.S. Pat. No. 9,331,389, issued on May
3, 2016, which is a continuation-in-part of U.S. patent application
Ser. No. 13/803,100 filed Mar. 14, 2013, which is now U.S. Pat. No.
9,379,443, issued on Jun. 28, 2016, which claims priority under 35
U.S.C. .sctn.119(e) from U.S. Provisional Patent Application Serial
No. 61/671,906, filed Jul. 16, 2012, the entire contents of each of
which are hereby incorporated by reference.
BACKGROUND
[0002] The vast majority of the portable and handheld wireless
devices feature nowadays an internal antenna. Internal antennas,
particularly those in charge or providing connectivity for cellular
services (e.g. 2G, 3G and 4G services such as GSM, CDMA, WCDMA,
UMTS, LTE operated within their corresponding frequency bands)
require their customization for each model of wireless device as
the shape of the device and its radioelectric specifications
usually vary from model to model. On the other hand, it is a
conventional wisdom that antennas need to keep a certain size with
respect to the wavelength in order to radiate efficiently.
Therefore, current internal antennas including patches (e.g.
PIFAs), IFAs, monopoles and related antenna modules feature a size
or length proportional to an operating wavelength of the device,
quite typically on the order of a quarter of such operating
wavelength. In practice this means that existing internal antennas,
internal antenna modules and alike are about the size of the
shortest edge of mobile phone (about 35-40 mm for a typical phone,
between 40-55 mm in the case of a smartphone). Such a size is
particularly inconvenient as the space inside a mobile device is
severely limited. Particularly during the design process, the
integration of the antennas inside the device becomes a cumbersome
task due to the many handheld components such as displays,
batteries, speakers, vibrators, shieldings, and the like that
compete for real-state with the antenna. The electromagnetic fields
radiated by an antenna are quite sensitive to such neighboring
components, which makes the design process even more difficult and
slow, as addressing all these issues usually involves multiple
design iterations. Finally, the fact that the antenna is sizeable
and not standard in shape makes its integration in an automatized
manufacturing process particularly challenging, which means that
most of the time the assembly of the antenna inside the device is
done manually.
[0003] Developing a small, standard antenna that would fit inside
every single handheld device would overcome many of the problems
related to the handset design and manufacturing process. However,
it is well known that reducing the antenna size to make it fit in
every handheld severely limits its performance, namely bandwidth
and efficiency. H. Wheeler and L. Chu, in the 1940's, first
described the fundamental limits on small antennas. They defined a
small antenna as an antenna fitting inside a radiansphere, that is,
an imaginary sphere of a diameter equal to the longest operating
wavelength of the antenna divided by pi (half an sphere in case of
unbalanced antennas such as monopoles). They concluded that below
such a limit, the maximum attainable bandwidth scales down with the
volume of the antenna relative to the wavelength volume (being the
wavelength volume a cube volume having an edge length equal to one
operating wavelength). In the limit, when the antenna becomes much
smaller than the wavelength, it radiates so inefficiently that it
can hardly be considered an antenna anymore.
[0004] In order to develop a standard radiation system featuring an
easy integration into wireless handheld devices, patent
applications WO 2010/015365, WO 2010/015364, WO 2011/095330, WO
2012/017013, U.S. 61/661,885, U.S. 61/671,906, disclose for
instance a new antenna related technology based on radiation
boosters. Such radiation boosters are electrically very small
elements (e.g. they feature small volumes fitting inside a cube
with an edge about only 1/30 wavelengths and below, typically below
1/50 of the longest operating wavelength), which are in charge of
properly exciting the electric currents of a ground plane mode for
radiation. Said ground plane is a conductive surface built in the
wireless handheld devices, typically including one conductive layer
on a printed circuit board which hosts the RF circuitry of the
wireless handheld device.
[0005] The radiating system in those patent applications further
comprises a radiofrequency system (including inductors, capacitors,
resistors, and transmission lines) in order to be operative in the
desired frequency band or frequency bands such as for example and
not limited to LTE700, GSM/CDMA850, GSM900, GSM1800, GSM/CDMA1900,
UMTS, LTE2100, LTE2300, LTE2500.
[0006] A prior art solution for a radiation booster disclosed, for
instance, a solid metal cube as the booster element. Such a cube
was designed to feature a very small size compared to the
wavelength while minimizing the ohmic resistance losses and
reactance of the element. Owing to its small size, a radiation
booster supports a significant current density, so a solid,
homogeneous, conductive cube option was proposed to minimize the
potential losses and reactance and therefore maximize the radiation
efficiency of the whole set. Therefore, that embodiment provided a
better performance than other boosters that concentrated all the
electric current through a single narrow, wire like element. In
another test, the miniature solid metal cube was also found to
feature a better performance (e.g., bandwidth and efficiency) than
a small, conductive thumbtack like booster placed over the ground
plane of the wireless device. So in summary, the solid metal cube
became over time a preferred solution for an efficient ground plane
booster within a wireless device.
[0007] Despite said solid conductive cube provided a top
performance compared to other booster elements, it still presented
multiple problems for real use applications in mass-produced
wireless devices, such as for instance: the element was quite heavy
owing to the density of its homogeneous metal structure; both the
conductive material and manufacturing procedure involving for
instance steel mills were far from optimum for producing large
quantities of boosters, and from the assembly and integration into
the wireless device perspectives, the high thermal conductivity of
the booster made it difficult to solder it onto the typical PCB of
a wireless device. In addition, due to their physical
characteristics, those cubes would not fit well within an automated
pick-and-place or SMD processes which are quite typical for PCB
electronics manufacturing.
SUMMARY
[0008] The present invention relates to the field of wireless
handheld or portable devices, and generally to wireless portable
devices which require both the transmission and reception of
electromagnetic wave signals.
[0009] It is an object of the present invention to provide a new
wireless handheld or portable device including a very compact,
small size and light weight radiation booster operating in a single
or in multiple frequency bands; that is, a radiation booster for a
radiating system embedded into a wireless handheld device, wherein
said radiating system including said booster is configured to both
transmit and receive simultaneously in a single band or in multiple
frequency bands. The present invention discloses radiation booster
structures and their manufacturing methods that enable reducing the
cost of both the booster and the entire wireless device embedding
said booster inside the device. In the context of the present
document the terms `radiation booster` and `booster` will be both
used indistinctly to refer to a `radiation booster` for a wireless
handheld or portable device according to the present invention.
[0010] It is an object of the present invention to provide a
wireless handheld or portable device (such as, for instance but not
limited to, a mobile phone, a smartphone, a phablet, a tablet, a
PDA, a digital music and/or video player (e.g. MP3, MP4), a
headset, a USB dongle, a laptop computer, a gaming device, a remote
control, a digital camera, a PCMCIA or Cardbus 32 card, a wireless
or cellular point of sale or remote paying device, or generally a
multifunction wireless device) comprising said radiation booster
for the transmission and reception of electromagnetic wave
signals.
[0011] A wireless handheld or portable device according to the
present invention operates one, two, three, four or more cellular
communication standards (such as for example GSM/CDMA 850, GSM 900,
GSM 1800, GSM/CDMA 1900, UMTS, HSDPA, CDMA, W-CDMA, CDMA2000,
TD-SCDMA, UMTS,LTE700, LTE2100, LTE2300, LTE2500, etc.), wireless
connectivity standards (such as for instance WiFi, IEEE802.11
standards, Bluetooth, ZigBee, UWB, WiMAX, WiBro, or other
high-speed standards), and/or broadcast standards (such as for
instance FM, DAB, XDARS, SDARS, DVB-H, DMB, T-DMB, or other related
digital or analog video and/or audio standards), each standard
being allocated in one or more frequency bands, and said frequency
bands being contained within one, two, three or more frequency
regions of the electromagnetic spectrum.
[0012] In the context of this document, a frequency band preferably
refers to a range of frequencies used by a particular cellular
communication standard, a wireless connectivity standard or a
broadcast standard; while a frequency region preferably refers to a
continuum of frequencies of the electromagnetic spectrum. For
example, the GSM 1800 standard is allocated in a frequency band
from 1710 MHz to 1880 MHz while the GSM 1900 standard is allocated
in a frequency band from 1850 MHz to 1990 MHz. A wireless device
operating the GSM 1800 and the GSM 1900 standards must have a
radiating system designed to operate in a frequency region from
1710MHz to 1990MHz. As another example, a wireless device operating
the GSM 1800 standard and the UMTS standard (allocated in a
frequency band from 1920 MHz to 2170 MHz), must have a radiating
system designed to operate in two separate frequency regions. In
some examples, a frequency region of operation (such as for example
the first and/or the second frequency region) of a radiating system
is preferably one of the following (or contained within one of the
following): 824-960 MHz, 1710-2170 MHz, 2.4-2.5 GHz, 3.4-3.6 GHz,
4.9-5.875 GHz, or 3.1-10.6 GHz.
[0013] According to the present invention, a wireless handheld or
portable device advantageously comprises at least five functional
blocks: a user interface module, a processing module, a memory
module, a communication module and a power management module. The
user interface module comprises a display, such as a high
resolution LCD, OLED or equivalent, and it is an energy consuming
module, most of the energy drain coming typically from the
backlight use. The user interface module may also comprise a keypad
and/or a touchscreen, and/or an embedded stylus pen. The processing
module, that is a microprocessor or a CPU, and the associated
memory module are also major sources of power consumption. The
fourth module responsible of energy consumption is the
communication module, an essential part of which is the radiating
system. The power management module of the wireless handheld or
portable device includes a source of energy (such as for instance,
but not limited to, a battery or a fuel cell) and a power
management circuit that manages the energy of the device.
[0014] In accordance with the present invention, the communication
module of a wireless handheld or portable device includes a
radiating system configured to both transmit and receive
electromagnetic wave signals in at least one frequency region of
the electromagnetic spectrum. Said radiating system comprises a
radiating structure comprising: at least one ground plane layer
configured to support at least one radiation mode, the at least one
ground plane layer including at least one connection point; at
least one radiation booster to couple electromagnetic energy
from/to the at least one ground plane layer, the/each radiation
booster including a connection point; and at least one internal
port. The/each internal port is defined between a connection point
of the/each radiation booster and one of the at least one
connection points of the at least one ground plane layer. The
radiating system further comprises a radiofrequency system, and an
external port.
[0015] In some embodiments according to the present invention, each
of the boosters disclosed here are designed to be arranged in a
clearance of the at least one ground plane. A clearance is for
instance a region of the ground plane underneath the booster where
a substantial portion of the metal is removed. According to the
present invention a booster is mounted on a clearance when the
projection or footprint of the booster on the plane comprising said
at least one ground plane does not intersect substantially with a
portion of the conductive surface of said ground plane. For
instance, in some of such embodiments the booster is configured so
that its footprint overlaps a ground plane conductive surface in
60% or less of the booster's footprint. Still, in many of said
embodiments a smaller overlap between the booster footprint and the
conductive ground plane is preferred, for instance a 50% or less, a
20% or less or even a 5% or a 0% overlap of the booster's
footprint.
[0016] In some cases, the radiating system of a wireless handheld
or portable device comprises a radiating structure consisting of:
at least one ground plane layer including at least one connection
point; at least one radiation booster, the/each radiation booster
including a connection point; and at least one internal port. In
some embodiments a radiation booster comprises two, three or more
points that define, together with a corresponding point on a ground
plane, two, three or more internal ports.
[0017] The radiofrequency system comprises a port connected to each
of the at least one internal ports of the radiating structure
(i.e., as many ports as there are internal ports in the radiating
structure), and a port connected to the external port of the
radiating system. Said radiofrequency system modifies the impedance
of the radiating structure, providing impedance matching to the
radiating system in the one or more frequency regions of operation
of the radiating system.
[0018] In this text, a port of the radiating structure is referred
to as an internal port; while a port of the radiating system is
referred to as an external port. In this context, the terms
"internal" and "external" when referring to a port are used simply
to distinguish a port of the radiating structure from a port of the
radiating system, and carry no implication as to whether a port is
accessible from the outside or not.
[0019] In some embodiments, the radiating structure comprises two,
three, four or more radiation boosters according to the present
invention, each of said radiation boosters including a connection
point, and each of said connection points defining, together with a
connection point of the at least one ground plane layer, an
internal port of the radiating structure. Therefore, in some
embodiments the radiating structure comprises two, three, four or
more radiation boosters, and correspondingly two, three, four or
more internal ports.
[0020] It is an object of the present invention to provide a new
very compact, small size and light weight radiation booster
operating in a single or in multiple frequency bands; that is, a
radiation booster for a radiating system embedded into a wireless
handheld device, wherein said radiating system including said
booster is configured to both transmit and receive simultaneously
in a single band or in multiple frequency bands. In particular, the
present invention discloses multiple structures for radiation
boosters to enable its standard integration into wireless handheld
devices. Some of the main benefits derived from the present
invention are: a faster time to market for wireless handhelds; a
lower manufacturing costs and scalability for large scale
manufacturing, including simplification and automatization of the
assembly and soldering process in large scale production; a low
weight and small size solution, together with the benefits of
enabling a standard radiation solution across multiple handheld
wireless platforms.
[0021] In order to achieve the aforementioned features, the present
invention provides a method for manufacturing radiation boosters.
The invention also provides an integrated package solution for both
the radiation boosters and the related radiofrequency system.
[0022] A radiation booster according to the present invention might
comprise a concave conductive structure. In the context of the
present invention, a geometry, whether 2D or 3D, is convex if for
every pair of points within the geometry every point on the
straight line segment that joins them belongs to the geometry. The
opposite is called a concave or non-convex geometry. For instance,
a solid homogeneous cube is convex, while the whole set of walls
enclosing the cube is, by itself a concave geometry.
[0023] A radiation booster according to the present invention
comprises a conductive concave structure entirely fitting inside a
cube with an edge length smaller than the longest operating
wavelength divided by 20. In some further examples, the radiation
booster has a maximum size smaller than 1/30 , 1/40, 1/50, 1/60,
1/80, 1/100, 1/140 or even 1/180 times the free-space wavelength
corresponding to the lowest frequency of the lowest frequency
region of operation of the device.
[0024] In some embodiments according to the present invention, a
conductive concave structure will entirely fit inside a limiting
volume equal or smaller than L.sup.3/8000 and in some cases equal
or smaller than L.sup.3/30000, and in some cases equal or smaller
than L.sup.3/100000, and in some cases equal or smaller than
L.sup.3/125000, L.sup.3/200000, L.sup.3/250000 or even smaller than
L.sup.3/500000 being L the longest free-space operating wavelength
of the booster.
[0025] In some embodiments, said limiting volume is a cube, while
in others it might be a hexahedron such as, for instance, a cuboid
or a prism such as for instance a rectangular prism. In some
embodiments, the longest edge of said limiting volume will be equal
or smaller than L/50, but preferably smaller than L/60 and L/70. In
some very small boosters, the limiting volume will feature a
longest edge equal or smaller than L/100, a volume equal or smaller
than L.sup.3/1000000 or a combination of both features. For the
avoidance of doubt, a conductive concave structure according to the
present invention should not be interpreted as a portion of a
larger homogeneous conductive structure which would extend beyond
said limiting volume. In addition, in some embodiments, the
radiation booster is a miniature stand-alone electronic component
or individual part or piece that fits inside any of the limiting
volumes as described above. By a stand-alone component it is meant
that the component is a separate part that can be for instance
manufactured, distributed, sold and assembled into a wireless
handheld device independently of other electronic components.
[0026] A radiation booster according to the present invention might
comprise a surface conductive element. In the context of the
present invention a surface conductive element will be understood
as a surface-like conductive element featuring a substantially
balanced geometrical aspect ratio, for instance a maximum width not
narrower than 4 times a maximum length of the element. On the other
hand, a linear conductive element is understood as a conductive
element featuring a significantly unbalanced aspect ratio, for
instance a maximum length to maximum width ratio larger than 3:1.
According to the present invention, a surface conductive element
and a linear conductive element can be placed conformal to a
non-planar surface, for instance a dihedral surface, a curved
surface, a polyhedral surface, a cylindrical, conical or spherical
surface and alike. Also, it is understood that both surface and
linear conductive elements will necessarily have some thickness as
any real world conductive structure will have necessarily some
thickness, even if such a thickness is so thin as a single layer of
atoms, as for instance in the case of a graphene layer.
[0027] According to an embodiment of the present invention, a
stand-alone component including a radiation booster entirely
fitting inside a limiting volume as described above comprises a
conductive concave structure. For instance, such conductive concave
structure comprises a surface conductive element and one, two or
more linear conductive elements and the corresponding booster and
stand-alone component are configured to be arranged on a clearance
of the at least one ground plane. Preferably, a radiation booster
comprises two surface conductive elements and two linear elements,
one, two or more of said linear elements interconnecting said two
surface conductive elements. In some of such embodiments one or
more of such two or more conductive surfaces feature a convex
geometry, while in other embodiments it features a concave
geometry. By using two or more linear elements and two surface
conductive elements, the electric current related to an operating
wavelength becomes distributed over said elements reducing the
losses and therefore increasing the efficiency of the overall
radiation system, and in turn, the radiation efficiency of the
overall handheld wireless device. This way, despite of the concave
arrangement of the conductors in the radiation booster, the overall
efficiency of the radiation system is kept within an operable
range. By improving the overall efficiency, the wireless device
will feature an increased coverage range, an improved sensitivity,
a better quality communication link and overall an enhanced user
experience. In addition, the use of concave conductive structure
has several advantages compared to a convex one; for instance, a
concave conductive structure is combined in several embodiments
with a dielectric element. Such a dielectric element might be a
printed circuit board, a glass fiber composite, a ceramic material,
a plastic material, a foam material or a combination of them. The
concave metal structure is designed in some of those cases such
that at least a portion of it is made conformal to said dielectric
element. This way the dielectric element mostly provides mechanical
stability and manufacturability features to the stand-alone
component, while said metal structure supports the electric
currents at the operating frequency bands of the radiating
system.
[0028] In some embodiments, a radiation booster featuring a size
smaller than one of the limiting volumes listed above comprises a
concave structure consisting of two or more surface conductive
elements interconnected side by side through at least one edge
within said elements. In some embodiments, by excluding the use of
linear elements the efficiency of the booster might be increased,
to the expense of maybe some additional cost in the manufacturing
of said booster.
[0029] In some embodiments, the radiation booster entirely fitting
inside a limiting volume as described above according to the
present invention comprises two linear elements. For instance, by
wrapping two or more linear elements around a dielectric material,
a radiation booster provides multiple connection points to a ground
plane which can be used for multiple purposes. In some embodiments,
said boosters are configured to split the current between elements
therefore minimizing losses and inductance of the whole set. In
other embodiments they are configured to provide more flexibility
to the electric component in terms of impedance tuning and
matching.
[0030] Owing to the very small size and construction of the
conducting structure of the booster, a radiation booster according
to multiple embodiments of the present invention in general but
also in every of the particular cases described above, might be
configured to feature a characteristic resonant frequency above any
of the operating bands of the booster. A characteristic resonant
frequency is understood as the resonant frequency of the booster
tested when mounted in the wireless device excluding any matching
network or loading reactive element between the booster input port
and the port of the frequency testing device. In some embodiments,
the ratio between said characteristic resonance frequency and the
lowest operating frequency of the booster is a factor of 3 or more;
in particular, sometimes said ratio is 4 or more or even 5, 6, 10
or more.
[0031] Commonly-owned patent applications WO2008/009391 and U.S.
2008/0018543 describe a multifunctional wireless device. The entire
disclosure of said application numbers WO2008/009391 and U.S.
2008/0018543 are hereby incorporated by reference.
[0032] Commonly-owned patent applications WO2010/015365,
WO2010/015364, WO2011/095330, WO2012/017013, U.S. Pat. No.
13/799,857, U.S. Pat. No. 13/803,100, U.S. 61/837,265,
EP13003171.9, describe wireless devices comprising a radiation
booster. The entire disclosure of said application numbers
WO2010/015365, WO2010/015364, WO2011/095330, WO2012/017013, U.S.
Pat. No. 13/799,857, U.S. Pat. No. 13/803,100, U.S. Pat. No.
61/837,265, EP13003171.9, are hereby incorporated by reference.
[0033] A stand-alone component fitting inside a limiting volume
according to the present invention comprises a radiation booster.
Said radiation booster comprises a conductive element and a
dielectric element. In some embodiments the conductive element is
attached to the dielectric element through a heat staking process.
In some embodiments the conductive element is affixed on the
dielectric element using printed circuit techniques. In other
embodiments the conductive element and the dielectric element are
combined using insertion molding (MID) techniques. Other radiation
booster architectures and manufacturing procedures that combine
conductive and dielectric elements according to the present
invention include: metallizing foams; gluing a rigid or flexible
conductive elements on a rigid or flexible dielectric, wrapping a
conductive fabric or conductive flexible material around a
dielectric element such as for instance a dielectric foam or foam
that is coated with a conductive material; wrapping one or more
graphene layers around a dielectric element; building a conductive
3D element on a 3D graphene structure such as for instance a
graphene foam. Without any limiting purpose, some examples of
conductive materials according to the present invention include:
copper, gold, silver, aluminum, brass, steel, tin, nickel, lithium,
lead, titanium, graphene.
[0034] A radiation booster entirely fitting inside a limiting
volume as described above comprises a first conductive surface on a
dielectric layer, said conductive surface connected to a conductive
linear element, said linear element connected to a second
conductive surface or linear element. For instance, said conductive
surface might include a convex or a concave metal shape printed on
a first metallic layer (for instance a copper layer) within a
multiple layer printed circuit board (PCB), said linear element
might be a via hole within said multiple layer PCB, and said second
conductive surface might be a convex or a concave metal shape
printed on a second metallic layer connected to said via hole. In
some embodiments, said conductive concave structure will include 2,
3, 4, 5, 6, 7, 8 or more linear or via hole elements to
interconnect said first and second conductive layers. In some
embodiments, said metal shapes would be a concave or a convex
substantially quadrilateral shape such as for instance a rectangle
or a square (either solid or including some holes or gaps in the
metal to make it concave), said one or more via holes
interconnecting said two or more metal shapes through a region
nearby the corners of said quadrilateral shapes. In some
embodiments, the booster element comprises 3 or more metal shapes
printed on 3 or more layers of said multiple layer PCB, together
with one or more via holes interconnecting said 3 or more metal
shapes, preferably nearby one or more corners within said metal
shapes. A radiation booster comprising a single-layer or multilayer
PCB, a plurality of metal shapes within one or more of said layers
of said PCB, and one or more conductive linear elements such as via
holes as described above is packaged as a surface mount device
(SMD) stand-alone component according to the present invention. The
SMD packaging of the booster benefits from a low cost manufacturing
process and a standardized pick-and-place assembly process into a
wireless device as discussed before.
[0035] In some embodiments, a radiation booster entirely fitting
inside a limiting volume as described above is embedded into an
integrated circuit (IC) package. In particular, the booster is
embedded in some embodiments in a stand-alone component featuring
for instance one of the following IC packaging architectures:
single-in-line (SIL), dual-in-line (DIL), dual-in-line with surface
mount technology DIL-SMT, quad-flat-package (QFP), pin grid array
(PGA), ball grid array (BGA) and small outline packages. Other
suitable packaging architectures according to the present invention
are for instance: plastic ball grid array (PBGA), ceramic ball grid
array (CBGA), tape ball grid array (TBGA), super ball grid array
(SBGA), micro ball grid array .mu.BGA.RTM. and leadframe packages
and modules.
[0036] One of the benefits of integrating a radiation booster into
an integrated circuit package is that in some embodiments such a
package integrates additional electronic components. For instance,
the radiation booster might be integrated together with one or more
inductors, one or more capacitors, or a combination of both. Those
might be for instance discrete lumped elements mounted on the
package and/or they can be distributed elements printed or etched
on the package or on a semiconductor die. In particular, in some
embodiments the integrated circuit package embeds a radiation
booster and one or more elements of the radiofrequency system
comprised in the radiating system of the wireless handheld or
portable device. For instance, the IC package integrates a matching
network connected to a radiation booster. Said matching network
includes in some cases a reactance cancellation circuit, a
broadband matching circuit, a fine tuning circuit or every
combination of them.
[0037] A radiation booster entirely fitting inside a limiting
volume as described above comprises, according to the present
invention, a metallized foam structure, said foam structure
featuring preferably a polyhedral shape such as a prism or a
cylindrical shape, and either a closed-cell or open-cell structure
in a rigid or flexible form. In some embodiments, said rigid or
flexible foam is partially or totally wrapped with a conductive
fabric, while in others the conductive or metal material is
deposited in a surface of said foam by using techniques such as for
instance sputtering, printing, coating or chemical plating. While
in some embodiments the foam is dielectric, in other embodiments
the foam is made conductive as well to lower the ohmic resistance
and losses of the whole booster. A radiation booster entirely
fitting inside a limiting volume as described above comprises an
element selected from the group consisting of: a conductive
cushion, a conductive web, a conductive foam, a shield foam gasket,
a conductive elastomer. By building a booster on a foam structure
the resulting element combines the radioelectric performance of the
booster with the mechanical properties of the foam: light weight,
low cost, flexible geometry. This combination of electric and
mechanical features makes the resulting booster particularly
suitable for mobile wireless and cellular devices where such a
device needs to combine an optimum radiofrequency response with
light weight and low cost. Moreover, the flexible nature of a foam
based booster makes it easy to embed it inside a small handheld or
portable wireless device where other components and mechanical
elements might leave limited room for the booster. A foam based
booster is able to adapt to virtually any internal volume shape of
a wireless device therefore maximizing its volume without any
specific customization effort at the manufacturing stage.
[0038] A radiation booster entirely fitting inside a limiting
volume as described above comprises a concave conductive element
and a concave dielectric element. In some embodiments of such a
radiation booster, the concave conductive element is a stamped
piece of metal, wherein in some cases, said stamped metal includes
one, two or more bends. A stamped metal piece is affixed onto a
concave dielectric element for instance by means of heat-stacking
process. In some embodiments said conductive element is built on
the surface of the concave dielectric element by means of a double
injection molding process, a laser direct structuring (LDS) process
or generally a molded interconnect device (MID) technique.
[0039] A ultra small radiation booster according to the present
invention (e.g. featuring limiting volumes smaller than
L.sup.3/500000, L.sup.3/1000000, L.sup.3/2000000) uses a highly
conductive material to optimize the radioelectric performance of
the wireless or cellular handheld or portable device, particularly
of a device which transmits or both transmits and receives wireless
and/or cellular waves. Said highly conductive material is made of
one or more layers of silver or graphene which is associated to a
convex or a concave dielectric element. In some embodiments such
association is done by means of chemical vapor deposition,
spraying, sputtering or a coating technique. In some embodiment
said one or more layers is mechanically associated with a
dielectric element by means of adhesion. One, two or multiple
graphene layers according to the present invention can be affixed
onto a dielectric element by depositing the graphene on an adhesive
film wrapping said dielectric element.
[0040] In some embodiments, a wireless device according to the
present invention comprises a radiation booster, said radiation
booster featuring one or more functions in addition to contributing
to the transmission and reception of electromagnetic waves within
the radiating system. Said additional function or functions might
include one or more of the following: mechanical affixing two or
more parts of the wireless device; providing EM shielding
capabilities to the wireless device; providing grounding contact
between conductive elements of the wireless device; reducing
mechanical vibrations on the overall wireless device and/or
protecting it from mechanical crash; modifying the acoustic
properties of the wireless device or providing electric contact to
other circuit elements within said device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0041] FIG. 1 illustrates an example of a wireless handheld or
portable device including a radiating system according to the
present invention in an exploded view.
[0042] FIG. 2a shows a radiation booster comprising a cubic shape
comprising a top and bottom conductive parts connected with vias
and spaced by a dielectric support (for clarity purposes the
dielectric is drawn transparent).
[0043] FIG. 2b shows the radiation booster where the dielectric
support is opaque.
[0044] FIG. 2c shows a radiation booster comprising different
dimensions in X, Y, and Z axis.
[0045] FIG. 2d shows a radiation booster comprising one via.
[0046] FIG. 2e shows a radiation booster comprising three vias.
[0047] FIG. 2f shows a radiation booster comprising a cylindrical
shape.
[0048] FIG. 2g shows a radiation booster comprising a
parallelepiped comprising a top conductive part, a via, and a
pad.
[0049] FIG. 2h shows a radiation booster comprising a top
conductive part and two vias connected each one to a pad.
[0050] FIG. 2i shows a radiation booster comprising an SFC (Space
Filling Curve).
[0051] FIGS. 2j and 2k show radiation boosters comprising a concave
2D structure.
[0052] FIG. 3 is a schematic representation of an example of a
radiating system according to the present invention.
[0053] FIG. 4a is a general view of a radiating structure for a
radiating system, the radiating structure comprising a radiation
booster.
[0054] FIG. 4b is a detailed view of the radiation booster and the
connecting means.
[0055] FIG. 4c is a detailed view of the radiation booster,
components of a radiofrequency system and an integrated circuit
chip.
[0056] FIG. 5 is a block diagram of an example of a matching
network for a radiofrequency system used in a radiating system of
FIG. 3.
[0057] FIG. 6a is a schematic representation of a matching network
used in the radiofrequency system of FIG. 5.
[0058] FIG. 6b shows input impedance at an internal port when
disconnected from the matching network of the radiofrequency
system.
[0059] FIG. 6c shows input impedance after connection of a
reactance cancellation circuit to the internal port.
[0060] FIG. 6d shows impedance after the connection of a broadband
matching circuit in cascade with the reactance cancellation
circuit.
[0061] FIG. 7a is a top view of a schematic of a radiation booster.
b) bottom view; c) lateral view.
[0062] FIG. 7b is a bottom view of a schematic of a radiation
booster.
[0063] FIG. 7c is a lateral view of a schematic of a radiation
booster.
[0064] FIG. 8a is a top view schematic of a radiation booster
having a thin profile.
[0065] FIG. 8b is a bottom view schematic of a radiation booster
having a thin profile.
[0066] FIG. 8c is a lateral view schematic of a radiation booster
having a thin profile.
[0067] FIG. 8d is a three-dimensional view schematic of a radiation
booster having a thin profile.
[0068] FIG. 8e is a three-dimensional view of a radiation booster
with a single connecting means between the top and bottom
parts.
[0069] FIG. 9 is an example of an integration of a radiation
booster with a package including several conductive means for
integrating a radiofrequency system.
[0070] FIG. 10 is an example of an integration of a radiation
booster with a package including a radiofrequency system comprising
SMD components.
[0071] FIG. 11 is an example of an integration of a radiation
booster with a package including a radiofrequency system comprising
SMD components using a T-type configuration.
[0072] FIG. 12a is an example of an integration of a radiation
booster with a package including a radiofrequency system comprising
SMD components and the integration in a radiating structure for a
radiating system
[0073] FIG. 12b is a more detailed view of the example of FIG.
12a.
[0074] FIG. 13 is an example of a package for integrating a
radiation booster and a radiofrequency system.
[0075] FIG. 14 is an example of two packages for a radiating system
including a radiation booster and conductive means for integrating
a radiofrequency system.
[0076] FIG. 15a is an example of two radiation boosters in package
connected by a connection means.
[0077] FIG. 15b is an example of interconnection of two
radiofrequency modules using a transmission line.
[0078] FIG. 16a is an example of packages for integrating a
radiation booster and a radiofrequency system showing a whole view
of a radiation booster and a radiofrequency system located below
the radiation booster.
[0079] FIG. 16b is an example of packages for integrating a
radiation booster and a radiofrequency system showing a particular
view of a radiation booster and a radiofrequency system located
below the radiation booster.
[0080] FIG. 16c shows an example of a lumped element embedded on
the radiation booster.
[0081] FIG. 17a is an example of a wireless handheld or portable
device including a radiating system comprising two radiation
boosters in a compact configuration.
[0082] FIG. 17b are examples of a package comprising two radiation
boosters.
[0083] FIG. 17c shows a package comprising two radiation boosters
and a SMD component to connect said two radiation boosters.
[0084] FIG. 18 is an example of a wireless handheld or portable
device including a radiating system comprising a radiation
booster.
[0085] FIG. 19 is an example of a radiating structure for a
radiating system, the radiating structure including a first and a
second radiation booster integrated in a laptop device.
[0086] FIG. 20 is an example of a radiating structure for a
radiating system, the radiating structure including a first and a
second radiation booster integrated in a tablet.
[0087] FIGS. 21a and 21b show an example of a radiation booster
made of FR4 comprising 4 vias and pads seen from two different
sides.
[0088] FIGS. 22a and 22b show examples of radiation boosters
fabricated using MID technology.
[0089] FIG. 23 is an example of a radiation booster fabricated
using a metallized foam process.
[0090] FIGS. 24a and 24b illustrate a method of fabricating a
radiation booster stamping a conductive surface to a dielectric
support.
[0091] FIG. 25 illustrates a method of fabricating a radiation
booster using a flexible conductor.
[0092] FIG. 26a illustrates a method of fabricating a radiation
booster using a flexible conductor comprising open faces in a 2D
representation.
[0093] FIG. 26b illustrates a method of fabricating a radiation
booster using a flexible conductor comprising open faces in a 3D
representation.
[0094] FIG. 27 is a radiation booster as described in the prior
art.
[0095] FIGS. 28a, 28b, and 28c show examples of radiating
structures for a radiating system, the radiating structures
including a reconfigurable radiation booster.
[0096] FIGS. 29a, 29b, and 29c show examples of radiating
structures comprising a radiation booster which can be
reconfigured.
[0097] FIGS. 30a and 30b show examples of concentrated radiation
boosters.
[0098] FIG. 31 is an example of two radiation boosters in a stacked
configuration.
[0099] FIG. 32 is an example of a radiation booster wrapped in
conductive fabric.
[0100] FIG. 33 is an example of a radiation booster wrapped in a
layer of graphene.
[0101] FIG. 34 is an example of a radiation booster made of a
graphene foam.
[0102] FIG. 35 is an example of a wireless handheld device reusing
an existing element as a radiation booster.
[0103] FIGS. 36a and 36b show an example of a radiation booster in
which the electrical current goes through all the sides of the
booster.
[0104] FIG. 37 is an example of a radiation booster comprising a
linear conductive element for advantageously cancelling the
reactance of the radiation booster.
[0105] FIG. 38 is an example of a radiation booster in package.
[0106] FIGS. 39a and 39b are examples of radiation boosters
arranged on a clearance area of a ground plane layer.
DETAILED DESCRIPTION
[0107] Further characteristics and advantages of the invention will
become apparent in view of the detailed description of some
preferred embodiments which follows. Said detailed description of
some preferred embodiments of the invention is given for purposes
of illustration only and in no way is meant as a definition of the
limits of the invention, made with reference to the accompanying
figures.
[0108] FIG. 1 shows an illustrative example of a wireless handheld
or portable device 100 according to the present invention. In FIG.
1a, there is shown an exploded perspective view of the wireless
handheld or portable device 100 comprising a radiating structure
that includes a first radiation booster 101a, a second radiation
booster 101b and a ground plane layer 102 (which might be included
in a layer of a multilayer Printed Circuit Board--PCB). Both
boosters 101a and 101b are stand-alone components fitting inside a
limiting volume selected among any of the limiting volumes
described in the present document. The wireless handheld or
portable device 100 also comprises a radiofrequency system 103,
which is interconnected with said radiating structure. Although in
this example the radiation boosters 101a and 101b are arranged on a
clearance area of the ground plane layer 102, in other words, there
is no overlapping between the footprints of the radiation boosters
and the conductive surface of the ground plane layer, in other
examples there is a partial overlapping between the footprints of
the radiation boosters and the conductive surface of the ground
plane layer.
[0109] FIG. 2a shows a preferred structure for a fabrication of a
stand-alone radiation booster 200. The said radiation booster 200
comprises a top 201 conductive part and a bottom 202 conductive
part, spaced by a dielectric support 203 having a parallelepiped
shape. For the present example, the parallelepiped is a cube, but
other prisms might be used as well. Both parts 201 and 202 are
connected by connecting means 204, 205, 206, and 207. The whole set
of conductive elements 201, 202, 204, 205, 206, 207 form a concave
conductive structure according to the present invention. Connecting
means 204, 205, 206 and 207 might be implemented for instance by
means of electroplated via holes. Other linear conductive elements
might be used to provide said connecting means.
[0110] In one embodiment, the dielectric support 203 is FR4 which
is a low cost material suitable for mass production. The connecting
means 204, 205, 206, and 207 are via holes which comprise a hole
through the dielectric support 203. Said via holes are metallized
so as to electrically connect the top conductive part 201 with the
bottom conductive part 202. This particular example comprises 4 via
holes 204, 205, 206, and 207 located substantially close to the
corners of the top 201 and bottom 202 parts.
[0111] For explanation purposes, the dielectric support 203 has
been drawn transparent. In reality, most of the dielectric supports
are opaque. Furthermore, the resulting structure is compatible with
SMD (Surface Mount Device) technology.
[0112] FIG. 2b shows the radiation booster 200 of FIG. 2a for an
opaque dielectric support 213. For a preferred example, the
dielectric support 213 is FR4/fiber glass. The radiation booster
210 comprises a top conductive part 211 and a bottom conductive
part 212 electrically connected by connecting means 214, 215, 216,
and 217.
[0113] The present novel structure for fabrication of a radiation
booster is suitable for mass production using standard PCB
manufacturing techniques.
[0114] FIG. 2c shows a stand-alone component including a radiation
booster 220 fitting inside a limiting volume as described above.
Booster 220 comprises a concave conductive structure and a
dielectric element. The geometry of booster 220 substantially
matches a parallelepiped volume, said parallelepiped defined by
three parallelograms 221, 222, 223 with a different area. In some
embodiments, said parallelepiped fits inside one or more of any of
the limiting volumes described in the present invention. Booster
220 comprises four linear elements such as for instance via holes
to electrically connect conductive surface elements placed on a
bottom surface 221 and on a top surface substantially parallel to
surface 221.
[0115] Component 220 is an example of a radiation booster featuring
a substantially cuboid geometry. This configuration may be
advantageously used to introduce a degree of freedom on the design
of the radiation booster and its integration in the wireless device
hosting it. An additional advantage of a cuboid shape as opposed to
a cube shape is that the manufacturing complexity and cost can be
reduced; this is achieved for instance by using a single standard
layer of dielectric material as opposed to stacking multiple
layers. This can be achieved by adjusting a thickness of the
component to match the standard thickness of a standard dielectric
layer (e.g. adjusting width height of 222 and 223), while
maintaining the overall volume of the component within a limiting
volume, by adjusting the remaining surfaces (e.g. 221).
[0116] FIG. 2d depicts a radiation booster including a concave
conductive structure, said concave structure comprising elements
conductive surface elements 232, 233 and linear element 231.
Booster 230 comprises one connecting means 231 connecting a top 232
and bottom 233 conductive parts. For this particular example, the
location of said connecting means 231 is preferably located
substantially at the center of both conductive top 232 and bottom
233 parts. In another example the location of said conductive means
231 is located close to a corner. A stand-alone component
comprising booster 233 fits in one or more of any of the limiting
volumes described in the present invention.
[0117] FIG. 2e depicts a radiation booster 240 according to the
present invention comprising three connecting means 241, 242, and
243 connecting a top 244 and bottom 245 conductive parts. A
stand-alone component comprising booster 240 fits in one or more of
any of the limiting volumes described in the present invention.
[0118] FIG. 2f shows a radiation booster 250 comprising a
cylindroid. For this particular example, the cross section of the
cylindroid is circular resulting in a cylinder shaped radiation
booster. In some embodiments the cross section of such a cylindroid
approaches a circular or elliptical sector as opposed to a full
circle or ellipse. This can be advantageously used to integrate a
radiation booster in a rounded cavity of a wireless handheld or
portable device. A stand-alone component comprising booster 250
fits in one or more of any of the limiting volumes described in the
present invention. In this particular embodiment four linear
elements such as for instance via holes connect conductive surfaces
placed on flat top and bottom surfaces of the cylindroid.
[0119] FIG. 2g shows a radiation booster 255 comprising concave
conductive structure and featuring substantially polyhedral form
factor approaching a parallelepiped. Said parallelepiped comprises
a top conductive surface element 256 connected to a small
conductive area (pad) 258 by means of a linear conductive element
such as for instance a via 257. Said conductive part 256 and pad
258 are printed on a dielectric element 259. In some examples said
dielectric support is FR4. This architecture of radiation booster
is advantageously used in PCB having ground plane underneath. Since
the radiation booster 255 has no bottom conductive part except for
a small portion defined by the pad 258, a ground plane can overlap
almost the overall footprint of the radiation booster. Therefore,
this radiation booster can overlap a ground plane of a wireless
handheld or portable device. The pad 258 is useful for connecting
the radiation booster to a radiofrequency system. A stand-alone
component comprising booster 255 fits in one or more of any of the
limiting volumes described in the present invention.
[0120] FIG. 2h shows a radiation booster 260 including a dielectric
element and a concave conductive structure comprising a top surface
conductive element 261 connected to pads 263 and 265 through linear
conductive elements (vias) 262 and 264, respectively. This example
is advantageously used to connect pad 263 to a radiofrequency
system, and pad 265 to a connection point of a ground plane. In
some other examples, the connection of pad 265 to a point of the
ground plane is done using a lumped circuital electric component.
This is useful for impedance matching purposes. Other linear
conductive elements such as for instance strips printed or etched
at the edges of the dielectric element might be used instead of the
via holes. A stand-alone component comprising booster 260 fits in
one or more of any of the limiting volumes described in the present
invention.
[0121] FIG. 2i shows a radiation booster 270, said booster
comprising a dielectric element 271 and a concave conductive
structure. Said concave conductive structure might include a
conductive space-filling structure (272) featuring 10 or more
linear conductive segments connected and forming an angle between
elements. Said space-filling structure might approach in some
embodiments the shape of a fractal geometry such as for instance a
Hilbert curve (272). In some embodiments said conductive
space-filling structure 272 is connected to pad 275 by means of the
via 274 and pad 273. In some embodiments said structure 272 is
connected to a surface conductive element, such as for instance a
surface printed in a layer of a multilayer dielectric element. A
stand-alone component comprising booster 270 fits in one or more of
any of the limiting volumes described in the present invention.
[0122] This architecture of the radiation booster 270 is
advantageously used for impedance matching purposes. In some
examples, the space-filling curve decreases the reactance behavior
of a radiation booster. This configuration allows simplifying the
reactance cancellation circuit of a radiofrequency system
associated to said radiation booster. The pad 275 is useful for
connecting the radiation booster to a radiofrequency system.
[0123] FIG. 2j shows a radiation booster 280 comprising a
conductive surface element 282 featuring a concave 2D shape and a
dielectric element 283. Said conductive surface element together
with linear conductive element 284 and pads 281 and 285 forms a
concave conductive 3D structure according to the present invention.
The pad 285 is useful for connecting the radiation booster to a
radiofrequency system.
[0124] FIG. 2k shows a similar example of a radiation booster 290
comprising a dielectric support 293, a top conductive part
comprising a concave 2D structure 295, a bottom conductive part
comprising a concave 2D structure 292 and a linear conductive
element 294. Both top and bottom conductive parts are connected
using the via 294. The bottom conductive part comprises a pad 291
useful for connecting the radiation booster to a radiofrequency
system. A stand-alone component comprising booster 280 or 290 fits
in one or more of any of the limiting volumes described in the
present invention.
[0125] In FIG. 3 it is depicted a radiating system 300 for a
wireless handheld or portable device according to the present
invention. The radiating system 300 comprises a radiating structure
301, a radiofrequency system 302, and an external port 303. The
radiating structure 301 comprises a radiation booster 304, which
includes a connection point 305, and a ground plane layer 306, said
ground plane layer also including a connection point 307. The
radiating structure 301 further comprises an internal port 308
defined between the connection point of the radiation booster 305
and the connection point of the ground plane layer 307.
Furthermore, the radiofrequency system 302 comprises two ports: a
first port 309 is connected to the internal port of the radiating
structure 308, and a second port 310 is connected to the external
port of the radiating system 303.
[0126] FIG. 4a depicts an example of a radiating structure 400
suitable for a radiating system 300. The radiating structure
comprises a stand-alone component comprising a radiation booster
401 according to the present invention and a ground plane layer
402. In this example, a ground plane layer 402 is printed on a
layer of dielectric substrate 404 which can be for instance a rigid
substrate (e.g. FR4) or a flexible film. The ground plane layer
comprises connecting means 403 for a radiofrequency system.
[0127] FIG. 4b shows a detailed view of a radiating system
comprising a radiating structure including a radiation booster 430
and a ground plane layer 436 printed on a layer of dielectric
substrate 435. The radiating system further comprises conductive
means 403 for a radiofrequency system. For this particular example,
the ground plane layer 436 comprises conductive areas or pads 432,
433, and 434 to allocate components for a radiofrequency system. In
some embodiments one or more of said pads are directly connected to
a ground plane layer 436, in other embodiments none of the pads are
directly connected to a ground plane. The radiation booster 430
comprises a bottom conductive layer 431 directly connected to a
conductive means 432. For illustrative purposes, the bottom
conductive part 431 is shown transparent in order to show the pad
432 which overlaps the said bottom conductive part 431. Said
overlap is useful to solder the radiation booster 430 to said pad
432 by applying heat through the via 437.
[0128] FIG. 4c shows a detailed view of the components 467, 468,
469, 470, and 471 of the radiofrequency system 403. For this
particular example, the radiation booster 460 comprises a bottom
conductive layer 461 which is directly connected to a first port of
the radiofrequency system 403. For a preferred example, the
radiofrequency system comprises a reactance cancellation element
467 and a broadband matching network comprising two shunt reactive
elements 468 and 469 connected to conductive area 463. A final
stage comprising components 470 and 471 adds flexibility for
impedance fine tuning purposes. In some examples, there is no need
to add a fine tuning stage and therefore, components 470 and 471
are not included or can be for instance jumper elements (0 ohm
resistance components). The external port of the radiofrequency
system 403 is connected to a port of an integrated circuit chip 473
performing radiofrequency functionality by means of a jumper 472.
For this particular example, said jumper 472 is a 0 ohms resistance
using a SMD component. In the same manner as described in FIG. 4b,
the radiation booster 460 is soldered to pad 462 by injecting heat
through the via 474. The ground plane layer 466 is printed on a
layer of dielectric substrate 465.
[0129] According to the present invention, each of the radiation
boosters shown in embodiments 400, 430 and 460 might be replaced in
other embodiments by each of the radiation boosters described in
the present document.
[0130] In relation with FIG. 3, the internal port 308 is defined
between a connection point 462 of the radiation booster 460 and a
connection point of the ground plane 466. The first port of the
radiofrequency system 403 (equivalent to 302 of FIG. 3) is defined
between a connection point of the conductive means 462 and a
connection point of the ground plane layer 466. The second port of
the radiofrequency system 403 (equivalent to 302 of FIG. 3) is
defined between a connection point of the conductive means 464 and
a connection point of the ground plane layer 466.
[0131] In FIG. 5 a matching network 500 comprises a reactance
cancellation circuit 503. In this example, a first port of the
reactance cancellation circuit 504 may be operationally connected
to the first port of the matching network 501 and another port of
the reactance cancellation circuit 505 may be operationally
connected to a second port of the matching network 502.
[0132] FIG. 6a is a schematic representation of the matching
network 600, which comprises a first port 601 to be connected to
the internal port of the radiating structure 400, and a second port
602 to be connected to the external port of a radiating system. In
this example, the matching network 600 further comprises a
reactance cancellation circuit 607 and a broadband matching circuit
608.
[0133] The reactance cancellation circuit 607 includes one stage
comprising one single circuit component 604 arranged in series and
featuring a substantially inductive behavior in the first and
second frequency regions. In this particular example, the circuit
component 604 is a lumped inductor. The inductive behavior of the
reactance cancellation circuit 607 advantageously compensates the
capacitive component of the input impedance of the first internal
port of the radiating structure 400.
[0134] With the small dimensions of a radiation booster according
to the present invention, the input impedance of the radiating
structure 400 measured at the internal port, features an important
reactive component (non-resonant element) within the frequencies of
operation when disconnected from the radiofrequency system. Said
reactive component is inductive when its value is greater than zero
and it is capacitive when its value is smaller than zero.
[0135] In FIG. 6b, curve 630 represents on a Smith chart a typical
complex impedance at the internal port of the radiating structure
400 as a function of the frequency when no radiofrequency system is
connected to said first internal port. In particular, point 631
corresponds to the input impedance at the lowest frequency of a
frequency region, and point 632 corresponds to the input impedance
at the highest frequency of the said frequency region.
[0136] Curve 630 is located on the lower half of the Smith chart,
which indeed indicates that the input impedance at the first
internal port has a capacitive component (i.e., the imaginary part
of the input impedance has a negative value) for at least all
frequencies of a first frequency range (i.e., between point 631 and
point 632).
[0137] The reactance cancellation effect can be observed in FIG.
6c, in which the input impedance at the first internal port of the
radiating structure 400 (curve 630 in FIG. 6b) is transformed by
the reactance cancellation circuit 607 into an impedance having an
imaginary part substantially close to zero in a frequency region
(see FIG. 6c). Curve 660 in FIG. 6c corresponds to the input
impedance that would be observed at the second port 602 of the
first matching network 504 if the broadband matching circuit 608
were removed and said second port 602 were directly connected to a
port 603. Said curve 660 crosses the horizontal axis of the Smith
Chart at a point 661 located between point 631 and point 632, which
means that the input impedance at the internal port of the
radiating structure 400 has an imaginary part equal to zero for a
frequency advantageously between the lowest and highest frequencies
of a first frequency region.
[0138] The broadband matching circuit 608 includes also one stage
and is connected in cascade with the reactance cancellation circuit
607. Said stage of the broadband matching circuit 608 comprises two
circuit components: a first circuit component 605 is a lumped
inductor and a second circuit component 606 is a lumped capacitor.
Together, the circuit components 605 and 606 form a parallel LC
resonant circuit (i.e., said stage of the broadband matching
circuit 608 behaves substantially as a resonant circuit in the
frequency region of operation).
[0139] Comparing FIGS. 6c and 6d, it is noticed that the broadband
matching circuit 608 has the beneficial effect of "closing in" the
ends of curve 660 (i.e., transforming the curve 660 into another
curve 690 featuring a compact loop around the center of the Smith
chart). Thus, the resulting curve 690 exhibits an input impedance
(now, measured at the second port 602 when no other circuitry is
connected at port 602) within a voltage standing wave ratio (VSWR)
3:1referred to a reference impedance of 50 Ohms over a broader
range of frequencies.
[0140] FIGS. 7a, 7b and 7c show another preferred scheme for a
fabrication of a radiation booster 700 seen from the top, the
bottom, and a side, respectively. Said radiation booster comprises
a first conductive part 701 and a second conductive part 751 spaced
by a dielectric element 760 such as for instance single layer
dielectric substrate or a multiple layer dielectric substrate. In
this particular example, 4 connection means 702, 703, 704, and 705
connect the first conductive part 701 with the second conductive
part 751. In some examples, the connecting means are via holes.
Said via holes comprise a hole from the first conductive part 701
to the second conductive part 751. Said hole is conductive so as to
electrically connect both parts 701 and 751. Conductive parts 701
and/or 751 might be a convex or a concave conductive structure
according to the present invention. A stand-alone component
comprising booster 700 fits in one or more of any of the limiting
volumes described in the present invention.
[0141] In yet another example, the top conductive part is covered
by a thin layer of ink (for example, a silk screen ink) which does
not affect the electromagnetic performance of the radiation booster
when it is integrated in a radiating system. Said ink layer is
useful for marking and/or marketing purposes. In some example, the
ink layer is used to mark a patent number. In some other examples,
a part number is printed in the ink layer. In some other examples,
the logo of the company is printed in said ink layer. Another ink
layer covers the bottom conductive part 751 except at small areas
752, 753, 754, and 755. Said small areas are conductive areas since
they are portions of the conductive part 751 not covered by the ink
layer. Said small conductive areas 752, 753, 754, and 755 are
called pads herein. The via holes 702, 703, 704, and 705
electrically connect the conductive second part 751 with the top
conductive part 701. With this configuration, the radiation booster
is a Surface Mount Device (SMD). This preferred radiation booster
product is compatible with industry standard soldering
processes.
[0142] At least one pad 752, 753, 754 and 755 is a connection point
305 of the radiation booster as shown in FIG. 3. Said connection
point with a connection point in the ground plane layer defines an
internal port of the radiating structure.
[0143] FIGS. 8a, 8b and 8c show another example of a radiation
booster 800 as the one described in FIG. 7 from a top view, a
bottom view, and a side view, respectively. For this example, the
thickness or height is at least five times less the shorter side of
the minimum quadrilateral that encloses either the top 801 or the
bottom 851 conductive parts. This is a low profile SMD radiation
booster which is suitable for slim wireless platforms. As in the
previous structure, four via holes 802, 803, 804, and 805
electrically connect through the substrate 860, the top conductive
part 801 with the bottom conductive part 851. At least one pad 852,
853, 854 and 855 is a connection point 305 of the radiation booster
as shown in FIG. 3. Said connection point with a connection point
in the ground plane layer defines an internal port of the radiating
structure.
[0144] FIG. 8d shows a 3D view of the SMD radiation booster
described in FIGS. 8a, 8b, and 8c. The radiation booster 830
comprises a top 831 and a bottom 832 conductive parts spaced by a
dielectric support 833 (shown transparent for illustrative
purposes). Both top 831 and bottom 832 conductive parts are
connected with vias 834, 835, 836, and 837.
[0145] FIG. 8e shows a radiation booster 860 comprising a top 861
and a bottom 862 conductive part spaced by a dielectric support
864. The radiation booster 860 comprises one via 863 connecting the
top conductive part 861 with the bottom conductive part 862. This
is a low profile radiation booster which is advantageously used for
slim wireless platforms.
[0146] FIG. 9 shows an example of a radiation booster in package
900. Said radiation booster in package 900 comprises a radiation
booster 901 and a radiofrequency module 902. The radiation booster
901 comprises a dielectric support 906, a top conductive part 903
and a bottom conductive part 904 connected by vias (an example of
via is shown in 905). The radiofrequency module 902 comprises
several conductive areas 908, 909, 910, 914 to host components for
a radiofrequency system. The conductive areas are called pads. The
radiofrequency module also comprises a pad 911 for connecting the
radiation booster in package to an integrated circuit chip of the
wireless handheld device in charge of transmitting and receiving
electromagnetic wave signals. The radiation booster in package also
comprises a pad 913 to connect it to a ground plane layer 402 as
the one shown in FIG. 4a. Pads 910 and 911 are connected through
via 917. In the same manner, pad 914 and 913, which are separated
by a dielectric support 915, are connected through via 912. The
radiation booster in package also comprises a pad 916 to fix the
package to a substrate 404 used to support a ground plane layer 402
(FIG. 4a). Said pad 916 in some example is soldered to a pad in the
substrate 404.
[0147] The radiation booster 901 further comprises a pad 908. Said
pad 908 defines a connection point 907. Said connection point with
a connection point of a ground plane layer defines the internal
port. Said port is connected to a port of a radiofrequency system
for matching purposes.
[0148] This radiation booster in package configuration is suitable
for a standard solution integrating both a radiation booster and a
radiofrequency module useful to host several components of a
radiofrequency system to provide operation at the desired frequency
bands. This scheme is useful because there is no need to customize
pads in a ground plane of a wireless handheld device.
[0149] FIG. 10 shows an example of the previous radiation booster
in package illustrating the components of a radiofrequency system
connected to a radiation booster 1001. The radiofrequency module
1002 of the radiation booster in package 1000 comprises several
pads to host a radiofrequency system. In this example, the
radiofrequency system comprises four components 1003, 1004, 1005,
and 1006. In a preferred embodiment, the component 1003 is a
reactance cancellation element comprising an inductor; a broadband
matching network comprising an LC resonator (1004 and 1005) and a
final stage 1006 which is a fine tune stage. In some examples, the
said fine stage is not necessary and therefore, 1006 is a jumper,
for example, a 0 ohms resistance. The series element 1003 together
with shunt elements 1004 and 1005 are schematically represented in
the example of FIG. 6a.
[0150] This particular example is suitable for a radiating system
to provide operation in one, two or more bands within a frequency
region between 698 MHz and 806 MHz. In some other examples, this
particular example is suitable for a radiating system to provide
operation in a frequency region between 824 MHz and 960 MHz. In
other example, it provides operation between 690 MHz and 960 MHz.
In yet another example, it provides operation between 1710 MHz and
2170 MHz. In a further example, it provides operation between 1710
MHz and 2690 MHz.
[0151] FIG. 11 shows an example of a radiation booster in package
1100 comprising a radiation booster 1101 and a radiofrequency
module 1102. The radiofrequency module comprises a radiofrequency
system comprising a T-type network (1103, 1104, and 1105).
[0152] In other embodiments, a circuit package such as those in
FIG. 10 and FIG. 11 includes a second radiofrequency system
connected to said radiation booster, said second radiofrequency
system enabling the operation of the same booster within a second
frequency region selected from the group consisting of: 698 MHz-806
MHz; 824 MHz-960 MHz; 690 MHz-960 MHz; 1710 MHz and 2170 MHz; 1710
MHz and 2690 MHz.
[0153] FIG. 12a shows an example of an integration of a radiation
booster in package 1201 in a radiating system 1200. FIG. 12b shows
a detailed view of said integration. The radiation booster in
package 1201 comprises a bottom conductive surface 1205 overlapping
a pad 1206. This allows the radiation booster 1202 to be soldered
to the pad 1206 by injecting heat through via 1218. A connection
point in said pad 1206 with a connection point of the ground plane
layer 1204 defines an internal port of the radiating structure of
the radiating system 1200. This internal port is connected to a
first port of the radiofrequency system defined between a
connection point in the pad 1206 and a connection point in the
ground plane layer. A radiofrequency module 1203 of the radiation
booster in package 1201 comprises several pads to host a
radiofrequency system. Said radiofrequency system comprises a
series component 1207 (reactance cancellation), a broad band
matching network (1208 and 1209) and a fine-tuning stage (1210).
The second port of the radiofrequency system is defined between a
connection point in the pad 1211 and a connection point of the
ground plane layer 1204. Said port is connected to the external
port of the radiating system 1200 which is defined between a
connection point in the pad 1214 and a connection point in the
ground plane layer 1204. In this example, a series component 1215
connects the external port of the radiating system with an
integrated circuit chip 1216 performing radiofrequency
functionality. In some examples, said integrated circuit chip 1216
is a Front End Module in charge of providing a multiplexing
functionality. In this particular example, the ground plane layer
1204 is printed on a dielectric substrate 1217.
[0154] FIG. 13 shows a radiofrequency module 1300 comprising
several pads 1302, 1303, 1304, 1305 to host components for a
radiofrequency system and a radiation booster. In particular, the
pad 1302 allows the electrically connection between a radiation
booster as the ones described in FIGS. 2 (i.e., 2a through, 2k both
included), 7, 8, 22 and 23 where the bottom conductive part of a
radiation booster is electrically in contact with the pad 1302. At
the same time, said pad 1302 is in contact with pad 1303. The gap
between the pad 1303 and 1304 allows the integration of at least
one series component. The gap between the pad 1304 and 1305 allows
the integration of at least one shunt component. The gap between
the pad 1304 and 1306 allows the integration of at least one series
component. The pad 1306 is electrically connected to a pad 1308 by
a via 1310. The pad 1305 is connected to pad 1309 through via 1307.
The pad 1305 is intended to provide a ground connection which is
provided by electrically connecting pad 1309 with a point in a
ground plane layer.
[0155] In particular this configuration is preferred to integrate a
radiation booster as the ones shown in FIGS. 2, 7, 8, 22 and 23.
Furthermore, this radiofrequency package is preferred to integrate
a series inductor connecting pad 1303 and 1304, a broadband LC
matching network connecting pad 1304 and 1305, and a series
component connecting pad 1304 and pad 1306.
[0156] This radiofrequency package is supported by a dielectric
support 1301. In some examples, this dielectric support is FR4,
glass fiber or glass epoxy, which are suitable for mass production
at a competitive cost. The advantage of this radiofrequency module
is that minimum customization of a PCB of a wireless handheld
device is required since the needed pads are allocated in the
radiofrequency module.
[0157] FIG. 14 shows a radiating structure 1400 for a radiating
system operating in a first and a second frequency region of the
electromagnetic spectrum. For a particular example, the radiation
booster in package 1401 is suitable for exciting an efficient
radiation mode of the ground plane and thus providing operation in
a first frequency region of the electromagnetic spectrum. In a
similar manner, the radiation booster in package 1402 is suitable
for exciting an efficient radiation mode of the ground plane and
thus providing operation in a second frequency region of the
electromagnetic spectrum. In some examples a first frequency region
ranges from 698 MHz to 960 MHz and a second frequency region ranges
from 1710 MHz to 2690 MHz. In some other examples, both radiation
boosters in package provide operation in the same frequency range.
This particular embodiment is particularly useful to provide
robustness to human loading effects. For instance, when the finger
of the user blocks one radiation booster in package, the other is
still free to operate. In yet another example, both radiation
booster in package operate in the same frequency region to provide
MIMO operation, for example at least one of LTE700, LTE2100,
LTE2300, LTE2500. In this example, the radiating structure 1400 has
a ground plane layer 1403 printed on a dielectric substrate 1404.
In this example, the footprints of the radiation boosters 1401 and
1402 do not intersect the conductive surface of the ground plane
layer due to their arrangement on a clearance area of the ground
plane layer 1403.
[0158] FIG. 15 shows two radiation boosters in package 1500 and
1501 connected using a connection means 1502. One end of said
connection means 1502 is electrically connected to pad 1503 and the
other end of said connection means 1502 is electrically connected
to pad 1504.
[0159] In some preferred examples, the connection means 1502 is a
transmission line.
[0160] This is illustrated in FIG. 15b. FIG. 15b shows a first
radiation booster in package 1550 and a second radiation booster in
package 1551 connected by a transmission line 1552. Said
transmission line 1552 comprises a part 1553 connected in one end,
to pad 1557 through the component 1555. Said pad 1557 is at the
same time connected to a connection point in the ground plane layer
of a radiating structure. The other end of part 1553 of the
transmission line 1552 is connected to pad 1560 through component
1558. Said pad 1560 is at the same time connected to a connection
point in the ground plane layer of a radiating structure. The part
1554 (for example, the inner conductor of a microcoaxial cable) is
connected in one to pad 1556 through component 1555. The other end
of part 1554 is connected to pad 1559 through component 1558. In
some examples the components 1555 and 1558 are IPX connectors. Said
IPX connectors are SMD components. In some examples, the external
part of said connector is connected to pad 1557 and the inner part
to pad 1556. In some examples, the transmission line 1552 is a
microcoaxial cable. Said microcoaxial cable has an external part
1553 and an inner part 1552. Both parts 1554 and 1553 are
conductive parts. In some examples, the outer part of the
microaxial cable is electrically grounded through component 1555
and 1559.
[0161] FIG. 16a shows an example of a stand-alone component
including radiation booster in package element 1600, said element
1600 comprising a radiation booster 1601 and a radiofrequency
module 1605 stacked one to each other so as to form a compact
radiation booster in package different to the one described in FIG.
9. An advantage of this solution is to minimize the area occupied
when the radiation booster in package is integrated in a
device.
[0162] The radiation booster 1601 comprises a top 1601 and a bottom
1604 conductive parts connected by four vias as the one shown in
1603. Both top and bottom parts are spaced by a dielectric element
1602. The radiofrequency module 1605 including a dielectric
material 1607 is located underneath the radiation booster 1601. The
bottom layer of this radiofrequency module 1605 comprises several
conductive means (pads) 1608 useful to connect lumped components of
a radiofrequency system. The bottom conductive part 1604 of the
radiation booster 1601 is electrically connected to a pad of the
radiofrequency module by means of via 1606. The whole radiation
booster in package is fixed to the PCB of the device by means of
spacers (1609) which can be glued or soldered to the PCB of a
wireless handheld or portable device. Other kind or radiation
boosters as the ones described in FIG. 2 can benefit of this scheme
for obtaining a radiation booster in package.
[0163] As shown in FIG. 16b, pad 1652 from the radiofrequency
module 1650 is connected to the bottom conductive part 1604 of the
radiation booster 1601 with via 1651. A series component 1653 is
connected between pad 1652 and pad 1654. Two shunt components 1656
and 1657 are connected between 1654 and pad 1658. Said pad 1658 is
connected to a point of a ground plane later by means of via 1659.
A series component is connected between pad 1654 and 1660. Said pad
1660 is connected to via 1661. Said via is useful for connecting
the radiation booster in package to an integrated circuit chip
performing radiofrequency functionality.
[0164] FIG. 16c shows a radiation booster in package 1670
comprising a dielectric support 1678, a first conductive surface
1671 and a second conductive surface 1675 connected by, for
instance, conductive linear elements or vias as the one shown in
1674. It also comprises a third conductive surface 1672 connected
to a fourth conductive surface 1677 by for instance conductive
linear elements or vias. The bottom conductive part 1676 and 1677
comprises several pads 1679, 1680, 1681, 1682 which are useful for
connecting to a radiofrequency system or for soldering the
radiation booster in package 1670 to a PCB. The bottom conductive
parts 1676 and 1677 are in some examples covered by a thin layer of
ink (ex: silk screen ink) except for in the pads 1679, 1680, 1681,
1682 leaving the conductive part free. This particular embodiment
is useful for matching purposes since enables including one or more
lumped elements such as for instance 1673, said element connecting
both top conductive surface elements 1671 and 1672. Said lumped
element is in some examples an inductor. In some examples it is a
capacitor. In some examples it is a combination of an inductor and
capacitor. In some embodiments 1673 is an active element which is
useful for matching purposes. An additional advantage of lumped
element or elements such as 1673 is that they can provide
flexibility in the interconnection and dynamic arrangement of the
whole set. For instance, an active element as a switch can be
turned on and off depending on the operating band, meaning that
element 1670 might become a single radiation booster (when 1673
interconnects 1671 and 1672) or two functional, adjacent radiation
booster (when 1673 effectively disconnects 1671 and 1672).
Similarly, such connecting elements 1673 might take the form of
frequency selective elements (e.g. reactive elements, filters,
resonators) that would couple or uncouple elements 1671 and 1672
depending on the operating frequencies of the wireless device.
[0165] The input impedance of said radiation booster 1670 is such
that it becomes a non-resonant element (imaginary part of the input
impedance not equal to zero) for all frequencies of operation when
disconnected from a radiofrequency system. In this regard, when the
element 1673 is a 0 .OMEGA. resistance, the input impedance of said
radiation booster 1670 of a radiating system when disconnected from
its radiofrequency system is non-resonant for all frequencies of
operation.
[0166] As discussed, an advantage of this embodiment when removing
the lumped element 1673 is to provide two radiation boosters in the
same package. For this case, one radiation booster operates in a
frequency region and the other radiation booster in a different
frequency region. For example, one radiation booster operates (the
one comprising the top 1671 and bottom 1676 conductive parts) at
GSM850 and GSM900 and the other radiation booster (the one
comprising the top 1672 and bottom 1677 conductive parts) operates
at GSM1800, GSM1900, UMTS, LTE2100, LTE2300, and LTE2500.
[0167] FIG. 17a shows an illustrative example of wireless handheld
or portable device 1700, in an exploded view, designed for
multiband operation according to the present invention comprising a
radiating structure that includes a first radiation booster 1701, a
second radiation booster 1702, and a ground plane layer 1703 (which
could be included in a layer of a multilayer PCB). The wireless
handheld or portable device 1700 also comprises a radiofrequency
system 1704, which is interconnected with said radiating
structure.
[0168] In some examples, both radiation boosters 1701 and 1702
feature the same topology. For example, both radiation boosters
feature a substantially cubic shape as those described in FIG. 2.
This is advantageously used to minimize the number of different
parts in a device. Moreover, having the same radiation booster
topology avoids mounting errors of the radiation booster in a
wireless handheld or portable device.
[0169] In some other examples, the first radiation booster 1701 and
a second radiation booster 1702 feature a different form factor.
For instance, 1701 might feature a cubic topology as embodiments in
FIG. 2 and the second radiation booster 1702 features a
parallelepiped shape such as for instance an embodiment in FIG. 8.
This is advantageously used to optimize the performance at each
frequency region of operation associated to the radiation
boosters.
[0170] FIG. 17b shows a stand-alone component 1750 comprising two
radiation boosters embedded in a unitary dielectric structure or
support 1760. A first radiation booster includes a concave
conductive structure comprising conductive elements 1753, 1754 and
one or more conductive elements such as 1756. A second radiation
booster includes a concave conductive structure comprising
conductive elements 1751, 1752 and one or more conductive elements
such as 1755. While the figure describes the use of four conductive
elements 1756 and 1755 within each booster, the concave conductive
structure might include one, two, three, five or more of them as
well within each booster as well. In some embodiments one or more
of said boosters fits inside one or more of any of the limiting
volumes described in the present invention. In some embodiments,
the whole stand-alone component fits in one or more of any of the
limiting volumes described in the present invention.
[0171] Embodiments described in FIG. 17b are interesting for a
concentrated configuration as the one shown in FIG. 17a. In one
embodiment one radiation booster comprises a top 1751 and a bottom
conductive part 1752 connected by vias. In some examples, the
bottom conductive part is covered by a thin layer of ink (ex: silk
screen ink). Some areas do not have said thin layer, resulting in
pads 1757 and 1758 being useful for connection to a radiofrequency
system or for fixing the radiation booster to a PCB. In a similar
manner, a second radiation booster comprises a top 1753 and a
bottom 1754 conductive parts connected by vias as the ones shown in
1755 and 1756.
[0172] In particular, a first radiation booster in 1750 is
associated to a first frequency region and a second radiation
booster is associated to another frequency region making it
possible for the radiating system to provide operability for the
LTE 700/1700/1900/2300/2500, GSM 850/900/1800/1900, CDMA
850/1700/1900, WCDMA (UMTS) 850/900/1700/1900/2100.
[0173] An advantage of an embodiment featuring two or more
radiation boosters such as stand-alone component 1750 is that the
radiation boosters can be connected by an external circuitry so as
to a form a single electrically functioning unit such as for
instance a single radiation booster as illustrated in FIG. 17c. The
radiating structure 1770 comprises radiation boosters 1771 and 1772
which are connected by a component 1776 and conductive traces 1777.
In this particular example, the component 1776 is a SMD component.
In other examples, said component is a conductive trace printed in
the PCB 1773. The radiation booster 1771 is connected to a
radiofrequency system 1775 placed over a ground plane 1774.
[0174] FIG. 18 shows an illustrative example of wireless handheld
or portable device 1800, in an exploded view, designed to feature a
multiband operation according to the present invention comprising a
radiating structure that includes a radiation booster 1801.
[0175] FIG. 19 represents a wireless or cellular laptop including
two or more radiation boosters such as 1901 and 1902 according to
the present invention. In particular FIG. 19 shows a radiating
structure 1900 comprising two radiation boosters 1901 and 1902
located on a ground plane layer 1903 having dimensions and topology
that fits the form factor of a laptop so that the whole set can be
embedded completely inside a laptop. The radiation booster 1901 and
1902 include a conductive part featuring a polyhedral shape
comprising six faces. Although other geometries such as those
illustrated in figures above can be used instead. In some preferred
embodiments one or more boosters are placed substantially close to
an edge of the laptop. In some embodiments each of the two bodies
of the laptop connected through a hinge include one or more
radiation boosters.
[0176] The ground plane layer 1903 comprises two elements (bottom
part 1904 and upper part 1905). In some embodiments, elements 1904
and 1905 are electromagnetically coupled at one or more of the
frequencies of operation of the wireless or cellular laptop through
coupling means 1906 in the hinge area. In some embodiments elements
1904 and 1905 remain uncoupled at one or more of the frequencies of
operation of the wireless or cellular laptop.
[0177] In this particular example, the radiation boosters 1901 and
1902 are located in the upper body 1905 of the ground plane layer
1903 where a display will typically be placed, whereas in other
preferred examples, one or more radiation boosters are located in
the bottom body 1904 of the ground plane layer.
[0178] In a particular example, the radiation boosters 1901 and
1902 are located at the long upper edge of the upper part 1905 of
the ground plane layer 1903. In yet other examples, the radiation
boosters 1901 and 1902 are located close to the hinge of the ground
plane layer 1903. In a further example, a radiation 1901 is located
at the long upper edge of the upper part 1905 of the ground plane
layer while a second radiation booster 1902 is located at the long
upper edge of the bottom part 1904 of the ground plane layer
1903.
[0179] FIG. 20 shows a particular example of a radiating structure
2000 comprising four radiation boosters 2001, 2002, 2003, and 2004
placed at the corners of a ground plane layer 2005. This particular
example is suitable for providing MIMO operation. According to the
present invention, a cellphone, a smartphone, a tablet, a phablet
includes a radiating structure 2000 enabling MIMO capabilities to
the wireless or cellular device.
[0180] FIGS. 21a and 21b show an example of a radiation booster
2100, fabricated using a dielectric material 2103, seen from one
side and from an opposite side. The dielectric material is FR4 for
this example. Said radiation booster comprises a top conductive
part 2101 and a bottom conductive part 2102 connected by connecting
means (via holes that are shown with dashed lines for illustrative
purposes) 2104, 2105, 2106, and 2107. Both the top 2101 and bottom
2102 conductive parts are protected by a thin silk screen ink layer
placed on top of each conductive layer. For this particular
example, the thickness of said silk screen ink layer is 25 um. In
order to solder said radiation booster to a PCB, said silk screen
layer is removed so as to have the conductor free. This creates
four conductive means (pads) as shown in 2108, 2109, 2110, and
2111. At least one of these pads together with a connection point
in a ground plane conforms an internal port of a radiating
structure as the one shown in FIG. 3. A thin layer of ink 2112 in
the top conductive part 2101 is used for marking a logo of a
company. Some examples of placing said radiation booster 2100 in a
radiating system are illustrated in FIG. 4a , b, c, FIG. 9, FIG.
10, FIG. 11, FIG. 12, FIG. 14, FIG. 15a, b, FIG. 16a, FIG. 17, FIG.
18, FIG. 19, and FIG. 20. For this example, the size of the
radiation booster is 5 mm.times.5 mm.times.5 mm.
[0181] FIG. 22a shows another example of a radiation booster 2200
according to the present invention which is fabricated using for
instance an LMS and/or MID (Injection Molding Device) technique.
Said radiation booster 2200 comprises a top conductive part 2201
and a bottom conductive part 2202 connected by conductive means
2204, 2205, 2206, and 2207. Said conductive means 2204, 2205, 2206,
and 2207 are printed through the MID process on a dielectric
support 2203.
[0182] In some examples, the radiation booster 2200 is connected to
a radiofrequency module 1300. The bottom conductive part 2202 of
the radiation booster 2200 is connected to the conductive part 1302
of the radiofrequency module 1300.
[0183] In some examples, the radiation booster 2200 is integrated
in a ground plane layer as the radiation booster 430 of FIG.
4b.
[0184] FIG. 22b shows an example of a radiation booster 2230
fabricated using MID. Said radiation booster 2230 comprises a top
conductive part 2231 over a dielectric support 2234. Said
conductive part 2231 is connected to a pad 2233 by means of a
conductive strip 2232. This particular embodiment is particularly
advantageous when the radiation booster is placed over a PCB having
a ground plane underneath except under the pad 2233. Since the
radiation booster 2230 does not have a bottom conductive part
except for the small pad 2233, it is not short circuited by the
ground plane underneath.
[0185] FIG. 23 shows another example of a radiation booster 2300
fabricated using a metallized foam. This particular example shows a
radiation booster having a substantially cubic shape. In some other
examples, a substantially parallelepiped shaped radiation booster
comprises three faces 2301, 2302, and 2303 with a different area.
In some other examples, the parallelepiped comprises two faces 2301
and 2302 with the same area and different than 2303.
[0186] In some examples, the radiation booster 2300 is connected to
a radiofrequency module 1300. A conductive part 2301 or 2032 or
2303 of the radiation booster 2300 is connected to the conductive
part 1302 of the radiofrequency module 1300.
[0187] In some examples, the radiation booster 2300 is integrated
in a ground plane layer as the radiation booster 430 of FIG.
4b.
[0188] FIGS. 24a and 24b show an element and a step for a method of
fabricating a radiation booster through a metal-stamping process.
For this example, a concave 2D conductive surface 2400 comprises 6
square conductive faces 2401 comprising a hole (2403). The
conductive surface 2400 is bent by the imaginary dashed lines (as
the one shown in 2402). Once folded, the conductive surface 2400 is
attached to a support material 2450 (FIG. 24b), forming a 3D
concave conductive surface. Said support material has a cubic (or
substantially cubic) shape 2451. Said cubic shape comprises a small
protuberance (2452). Once the conductive surface 2400 is folded and
attached to the cubic shape 2451, the protuberances as 2452 are
melted by a heating process so as to fix the conductive surface
2400 to the cubic shape 2451. Said conductive surface 2400 is in
some examples a rigid conductor which can be easily bent following
the imaginary dashed lines as the one illustrated by 2402. In some
other examples, the conductive surface 2400 is a flexible material
which is easily folded. Said flexible material is attached to the
cubic shape 2450 following the same heating process described
above. However, in some embodiments, it is not necessary to have
protuberances as 2452 so as the flexible material is fixed to the
cubic shape by adhesive material. In some examples, the flexible
material is a flex-film which is easily bent. In some other
examples, the flexible material is graphene.
[0189] The connection of a radiation booster made up following this
method is carried out by adding a pogo pin in the PCB of the
wireless device which can be connected to a radiofrequency system.
In some other examples, the contact is made by pressure so as to
connect the radiation booster to a pad in the PCB. Said pad is then
connected to a radiofrequency system. In some other examples, the
radiation booster can be soldered to a pad of the ground plane
layer.
[0190] FIG. 25 shows an element and a step for a method of
fabricating a radiation booster 2500 comprising a flexible
conductive surface 2501 which is folded by the imaginary lines as
shown in 2502. Examples of flexible conductive materials are
flexfilm and graphene. In a similar manner, FIG. 26 shows another
example where the flexible conductive surface is simpler. Once
folded, the radiation booster can adopt the shape of a prism or a
parallelepiped with two open faces or even a cylinder with two open
ends. The connection can be made for instance by means of the same
methods explained in FIG. 24.
[0191] While FIGS. 24a, 24b, and 25 show 6 conductive faces that
substantially enclose an entire volume when folded in a 3D form
(such as in FIG. 24b), in other embodiments one or more of the
sides might be incomplete so that, when folded in a 3D form, the
resulting concave conductive structure does not completely enclose
an entire volume.
[0192] In other embodiments, one or more of the sides are
electrically disconnected from the remaining sides. This way, when
folded in a 3D form, two or more electrically disconnected
conductive structures are formed to be included in two or more
radiation boosters respectively.
[0193] FIGS. 26a and 26b show another method of fabricating a
radiation booster comprising a flexible conductive surface 2600. In
FIG. 26a, when folded by the imaginary lines, the resulting object
has two open faces as seen in FIG. 26b. In some examples, the
resulting shape forms a closed loop. In some other examples, the
resulting shape is an open-loop. This may be particularly
advantageous for impedance matching purposes.
[0194] FIG. 27 shows an example of a radiation booster 2700 as
described in the prior art. This example shows a solid cube made up
of brass which is a bulky, heavy structure, difficult to solder and
to manufacture in large quantities at a low cost.
[0195] FIG. 28a shows an example of a radiating structure 2800
comprising a stand-alone component 2802 including a radiation
booster. In this example, the stand-alone component is on one side
of a ground plane layer 2801, on top of an indentation or slot in
said ground plane layer. The stand-alone component comprises a
dielectric support 2811 (shown transparent with dashed lines for
illustrative purposes) and one or more linear conductive elements,
such as for instance metallic strips 2803, 2804 and 2805, used for
coupling energy and/or reconfiguring the radiation booster 2802.
Each metallic strip is connected with linear conductive elements
2808, for instance via holes, to pads 2806 and 2807 located beneath
the ends of the metallic strips. A strip together with a vertical
via and the pad or pads at the end of a via or vias form a concave
conductive element according to the present invention. In this
particular embodiment, the connection from an integrated circuit
chip with radiofrequency functionality 2812 to the ground plane
2810 is done through strip 2803 with a connection means 2809. The
dielectric support 2811 is soldered to the ground plane layer 2801
in the overlapping area applying heat to the vias arriving to
soldering pads 2813.
[0196] Diverse interconnections between the metallic strips through
their pads permit the tuning of the radiation booster 2802, which
is advantageous for adjusting the electric characteristics of the
booster without modifying the ground plane layer 2801. Some of the
possible interconnections are shown in FIGS. 28b and 28c.
[0197] In some examples, the indentation in the ground plane layer
2801 has a physical dimension smaller than a fourth, or than a
tenth, or than a fiftieth of the longest free-space operating
wavelength of the booster. In some other examples, the physical
dimension of the indentation in the ground plane layer is about a
fourth of the longest free-space operating wavelength of the
radiation booster.
[0198] FIG. 28b shows an example of a radiating structure 2830
similar to the one in FIG. 28a, in which the tuning of the
radiation booster 2802 is done with metallic strip 2804 and an SMD
component 2831 for impedance matching purposes prior to the
connection to the ground plane 2810.
[0199] FIG. 28c shows another example of a radiating structure 2850
configured to modify, (e.g. maximize) the electrical path of the
currents. The metallic strips 2803, 2804 and 2805 are
interconnected for instance to increase the length of the path from
the chip 2812, which can be a front end module in other
embodiments, to the ground plane 2810. Specifically, conductive
areas 2806 from linear conductive elements 2803 and 2804 are
interconnected with for instance a conductive trace 2851, and pads
2807 corresponding to linear conductive elements 2804 and 2805 are
also interconnected with conductive trace 2852. In other examples,
the pads are interconnected with elements such as jumpers,
inductors, capacitors, switches or other components that allow
reconfiguring the electric characteristics of the booster.
[0200] A stand-alone component comprising radiation booster 2802
fits in one or more of any of the limiting volumes described in the
present invention.
[0201] FIG. 29a shows a radiating structure 2900 that comprises a
stand-alone component 2902 in the ground plane layer 2901. The
stand-alone component, which includes a radiation booster,
comprises a dielectric support 2903 and a linear conductive element
in the form of a strip for advantageously tuning the radiation
booster 2902. The linear conductive element can be printed or
etched at the edges of the dielectric element for instance, and the
ends of said conductive element are connected to the feeding point
2905 and to the ground plane 2908 with a connecting means 2906.
Said strip comprises two or more parts, such as for instance three
parts 2910, 2911 and 2912 which result in several gaps for
allocating components (SMD components for example) in series for
further adjustment of the electric performance of the radiation
booster 2902. The dielectric support is soldered to pads 2907 for
its attachment to the ground plane layer 2901.
[0202] FIG. 29b shows an example of a radiating structure 2930
similar to 2900 where the radiation booster 2940 features a linear
conductive element such as metallic strip 2904 and further
comprises a conductive surface element 2931. In this example,
element 2931 might be used to connect one or more shunt components
2932 in addition to components in series 2933, for instance SMD
components. The use of, for instance, integrated elements (such as
for instance trace notches, gaps or narrow linear or meandering
strips) for capacitive or inductive coupling between conductive
areas instead of SMD components is also possible.
[0203] FIG. 29c shows another example of a radiating structure 2950
comprising a radiation booster 2960 in a stand-alone component
which is placed on a ground plane layer 2901 featuring a slot or an
indentation. In this embodiment, a matching network is provided
between feeding point 2905 and metallic strip 2951. Series 2954 and
shunt 2955 components are installed in pads 2952 provided on a
layer of dielectric substrate 2953.
[0204] A stand-alone component comprising radiation booster 2902,
or 2940, or 2960 from FIGS. 29a, 29b and 29c, fits in one or more
of any of the limiting volumes described in the present
invention.
[0205] In some embodiments, the physical dimension of the slot or
indentation is about a fourth of the longest free-space operating
wavelength of the radiation booster. In some other examples, the
slot or indentation in the ground plane layer 2901 has its physical
dimension smaller than a fourth, or than a tenth, or than a
fiftieth of the longest free-space operating wavelength of the
booster.
[0206] FIG. 30a shows a stand-alone component comprising two
concentrated radiation boosters 3000 in a dielectric support 3005
(shown transparent and with dashed lines for illustrative
purposes). In this particular example, the first radiation booster
3001 comprises three substantially quadrilateral sides 3003. The
second radiation booster 3002 also comprises three substantially
quadrilateral sides 3004. The first radiation booster 3001 is
configured to operate in a first frequency region, and the second
radiation booster 3002 is configured to operate in the same first
frequency region, or in a second frequency region, or a combination
of both.
[0207] In some other examples, the two radiation boosters comprise
different numbers of sides, for instance and without being limited
by these examples, the first radiation booster has four sides and
the second booster one or two sides. In other embodiments, a first
booster might substantially cover 5 sides and a second booster
might cover one side respectively.
[0208] FIG. 30b shows another example of a compact configuration
for two radiation boosters 3030, operating in two frequency
regions, in a dielectric support 3035 featuring a prism like shape.
In this example, the first radiation booster 3031 has two surface
conductive elements: a substantially quadrilateral one 3033, and
another one that is substantially quadrilateral 3036 which has an
approximate area equal to a fraction (e.g. half) of the area of the
quadrilateral side 3033. The second radiation booster 3032
comprises four substantially quadrilateral sides 3034 with
substantially same surface, and a fifth substantially quadrilateral
side 3037 that has different-sized surface (e.g. a smaller surface)
than the four quadrilateral sides 3034.
[0209] In other embodiments, the sides of the radiation boosters
have shapes different than quadrilaterals and the dielectric
substrate 3035 takes the form of a cylinder or cone for
instance.
[0210] Stand-alone components 30a and 30b might be built, for
instance, by stamping and bending conductive sheets which
eventually might become supported by a dielectric element, such as
for instance a plastic carriers including heat-stakes to attach the
stamped elements. In other embodiments, said components are
manufactured by means of a double injection process such as for
instance a MID technique, which can be for instance combined with
LDS. Still, in other embodiments, those stand-alone components are
manufactured by metallizing a dielectric foam. A stand-alone
component comprising boosters 3000 or 3030 fits in one or more of
any of the limiting volumes described in the present invention.
[0211] FIG. 31 shows an example of two stacked radiation boosters
3100 within a dielectric substrate 3108 that can be implemented on
a multiple layer dielectric substrate for instance. More
particularly, the first radiation booster comprises two conducting
surfaces 3102 interconnected with electroplated via holes 3104 or
the like (the pads are not represented in this figure) and has the
connection 3106 for a radiofrequency system that goes through an
opening 3107 in the bottom conducting surface 3101 of the second
radiation booster, whose top and bottom conducting surfaces are
interconnected with connecting means 3103 as well. The second
radiation booster also has a connection 3105 for a radiofrequency
system. In this example, the first radiation booster operates in a
first frequency region and the second booster operates in said
first frequency region, or in a second frequency region or in a
combination of both.
[0212] In other embodiments the connections 3105 and 3106 of both
radiation boosters can be arranged laterally with conductive traces
for instance, or in other different ways that would not require the
hole 3107 in one of the conductive surfaces.
[0213] FIG. 32 shows a radiation booster 3200 that is substantially
shaped as a rectangular cuboid and made of conductive or dielectric
foam 3201. The radiation booster has a plurality of its faces
wrapped in a conductive fabric 3202. In other embodiments, the
radiation booster may be, for instance, completely wrapped with
conductive fabric or with a layer of graphene. Radiation booster
3200 entirely fits in one or more of any of the limiting volumes
described in the present invention.
[0214] FIG. 33 shows a substantially cubic radiation booster 3300
that is a dielectric or conductive element 3301, and which has a
layer of graphene 3302 wrapping a plurality of the radiation
booster faces. The radiation booster may have, in other examples,
faces shaped as polygons different from squares, for instance
rectangles. Radiation booster 3300 entirely fits in one or more of
any of the limiting volumes described in the present invention.
[0215] FIG. 34 shows a radiation booster 3400 that is fabricated
using graphene foam. This particular example shows a radiation
booster having a substantially cubic shape but in other examples
the shape of the booster is substantially a parallelepiped or the
like. Radiation booster 3400 entirely fits in one or more of any of
the limiting volumes described in the present invention.
[0216] FIG. 35 shows an illustrative example of a wireless handheld
device 3500 in which an existing element of the device, that
already performs a particular task, is configured to additionally
function as a radiation booster according to the present invention.
In this particular example, under the back cover 3501 of the
cellular phone, a screw 3504 attaching, with a metallic connection,
a dielectric support 3502 inside the device (for holding the camera
of the device, for example) to the PCB 3503 is used as a radiation
booster. Additionally, one or a plurality of pads 3505 are provided
for integrating a matching network using SMD and/or integrated
components.
[0217] In some other embodiments, elements having metallic casings
and which are included in the device, such as a vibrating device
for example, are used as radiation boosters. In some other
embodiments, the device is a portable device such as a laptop.
[0218] FIG. 36 shows two-dimensional (a) and three-dimensional (b)
representations of a concave and substantially cubic radiation
booster 3600 whose sides are arranged in a sequential manner on a
dielectric support 3605. This arrangement makes the electrical path
3602 to be longer as the current goes through all conductive
surfaces 3601 starting in side 3603 and ending in side 3604.
[0219] In some other examples, the radiation booster is a
parallelepiped where the sequential arrangement of the radiation
booster sides is done with sides differently shaped, with shapes
such as rectangles or the like.
[0220] FIG. 37 shows an example of a radiation booster 3700
comprising a dielectric substrate 3703 and several conductive parts
(3701 and 3702) that can be implemented, for instance, on a
multilayer PCB. More specifically, a conductive element with
multiple substantially linear segments 3701 features an
advantageous inductive behavior that partially or completely
cancels the reactance of the radiation booster, where said
conductive element 3701 can be a conductive trace for instance. One
end of the curve is connected to pad 3707, which is used for
connecting the booster to the radiofrequency system, and the other
end of conductive element 3701 is coupled to the upper surface
conductive element 3702 of the radiation booster with a connection
to pad 3706. The top and the bottom conducting surfaces 3702 are
interconnected with linear conductive elements (e.g. vias) using
pads 3705.
[0221] In some other examples, the conductive element 3701 is
shaped as a space-filling curve featuring ten or more segments. In
this particular example, said element 3701 has the shape of a
Hilbert curve.
[0222] FIG. 38 shows an example of a radiation booster in package
3800. The top and the bottom conducting surfaces 3801 and 3802,
spaced by a dielectric support 3804, are connected with connection
means 3803, such as linear conducting elements or via holes, for
instance. Several pads 3806 (illustrated in white) provided on the
dielectric support 3805 (which could be FR4 for example) are used
for making electrical connection with the radiation booster, so
owing to the multiplicity of pads 3806 radiation boosters of
different sizes or form factors can be integrated. Additional
conducting areas 3807 (illustrated in gray) can allocate devices or
circuits like, for instance, reactance cancellation circuits,
filters, broadband matching networks or SMD components. This
advantageously reduces the integration of said types of devices on
the PCB of the device in which the radiation booster 3800 is
installed. The connection between pads 3806 and 3807 can be done
with shunt or series SMD components or conducting traces, for
example.
[0223] FIGS. 39a and 39b show examples of radiating structures 3900
and 3930 in which the footprint of a radiation booster 3902
partially overlaps the conductive part of the ground plane layer
3901 (a) and 3931 (b). In these examples, a clearance area 3903 (a)
and 3933 (b) is provided on the ground plane layer, wherein the
clearance area is a region with a substantial portion of the metal
of the ground plane layer removed. The part of the footprint of the
radiation booster 3902 that intersects with the conductive surface
of the ground plane layer is, for instance, less than a 50% in (a)
and less than 10% in (b) of the booster footprint (shown with
stripe pattern 3904 and 3934 for illustrative purposes only). In
other embodiments, the footprint of the radiation booster overlaps
with the conductive part of the ground plane layer is about a 60%
or less, a 40% or less, a 30% or less, a 20% or less, a 5% or less
or even a 0% of the booster footprint.
[0224] The radiation booster 3902 can be any of the radiation
boosters described in the present invention.
* * * * *