U.S. patent application number 12/884056 was filed with the patent office on 2011-03-17 for passive repeater for wireless communications.
Invention is credited to Michael Clyde Walker.
Application Number | 20110063181 12/884056 |
Document ID | / |
Family ID | 43729994 |
Filed Date | 2011-03-17 |
United States Patent
Application |
20110063181 |
Kind Code |
A1 |
Walker; Michael Clyde |
March 17, 2011 |
PASSIVE REPEATER FOR WIRELESS COMMUNICATIONS
Abstract
Some embodiments provide a relatively small antenna apparatus
that acts as a passive repeater. The antenna apparatus can be
designed to facilitate radio frequency (RF) signal gain for a
collection or range of frequencies. In some embodiments, the
antenna apparatus is placed near a device with a wireless receiver
and/or transmitter, where the antenna apparatus causes increased RF
signal intensity at the device by coupling RF signals from a
proximate area of higher RF signal intensity into the area around
the device. Accordingly, in some instances, an embodiment of the
antenna apparatus can be used to increase the RF signal intensity
in a null spot or dead spot by coupling RF signal energy from an
area proximate to the null spot that has higher RF signal
intensity.
Inventors: |
Walker; Michael Clyde;
(National City, CA) |
Family ID: |
43729994 |
Appl. No.: |
12/884056 |
Filed: |
September 16, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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61243120 |
Sep 16, 2009 |
|
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61373222 |
Aug 12, 2010 |
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Current U.S.
Class: |
343/803 ;
343/818; 343/835; 343/836 |
Current CPC
Class: |
H01Q 25/005 20130101;
H01Q 9/16 20130101; H01Q 19/06 20130101; H01Q 19/108 20130101; H04B
7/145 20130101; H01Q 19/10 20130101; H01Q 19/30 20130101 |
Class at
Publication: |
343/803 ;
343/835; 343/818; 343/836 |
International
Class: |
H01Q 19/10 20060101
H01Q019/10; H01Q 21/00 20060101 H01Q021/00; H01Q 9/26 20060101
H01Q009/26 |
Claims
1. An antenna apparatus comprising: an electromagnetically
reflective layer, the electromagnetically reflective layer having
first and second faces; a first dielectric layer disposed on the
first face of the electromagnetically reflective layer; and a first
arrangement of conductors disposed on the first dielectric layer,
the first arrangement of conductors comprising: a first resonator
including a first antenna having a respective feed point, a second
antenna having a respective feed point, and a first coupling
element electrically connecting the respective feed points of the
first and second antennas; and a first reflector electrically
isolated from the first resonator and positioned adjacent to at
least one of the first and second antennas, and wherein a
longitudinal axis of the first reflector intersects the first
coupling element.
2. The antenna apparatus of claim 1, wherein the
electromagnetically reflective layer is one of rigid and
flexible.
3. The antenna apparatus of claim 1, wherein the first reflector
comprises first and second conductive portions separated by a gap
through which the first coupling element extends and intersects the
longitudinal axis of the reflector.
4. The antenna apparatus of claim 1, wherein the first reflector
comprises a single conductor, and the antenna apparatus further
comprises a dielectric separator interposed between the first
reflector and the first coupling element.
5. The antenna apparatus of claim 1, wherein at least one of the
first and second antennas is one of a dipole antenna, a rhombic
antenna, a planar antenna, and a yagi antenna.
6. The antenna apparatus of claim 1, wherein the first and second
antennas are folded dipole antennas, and the respective feed point
for each of the first and second antennas comprises first and
second feed terminals, and wherein the coupling element includes
first and second conductive traces, the first conductive trace
electrically connecting the respective first feed terminals of the
first and second antennas, and the second conductive trace
electrically connecting the respective second feed terminals of the
first and second antennas.
7. The antenna apparatus of claim 6, wherein at least one of the
first and second antennas includes an undulating portion.
8. The antenna apparatus of claim 6, wherein the first arrangement
of conductors further comprises: a second reflector electrically
isolated from the first resonator and positioned adjacent to the
second antenna, and wherein the longitudinal axis of the second
reflector intersects the first coupling element, and wherein the
first reflector is positioned adjacent to the first antenna.
9. The antenna apparatus of claim 8, wherein the first coupling
element is straight and the first and second antennas are arranged
so that the respective radiation pattern of one extends in the
substantially opposite direction of the other.
10. The antenna apparatus of claim 8, wherein the first coupling
element includes a corner and the first and second antennas are
arranged facing respective first and second directions.
11. The antenna apparatus of claim 8, wherein the first arrangement
of conductors further comprises at least one director in parallel
with at least one of the first and second reflectors, and wherein a
respective one of the first and second antennas is positioned
between the at least one director and respective one of the first
and second reflectors.
12. The antenna apparatus of claim 6, wherein the first arrangement
of conductors further comprises at least one director in parallel
with the first reflector, and wherein one of the first and second
antennas is positioned between the at least one director and the
first reflector.
13. The antenna apparatus of claim 6, wherein the first arrangement
of conductors further comprises a plurality of directors parallel
to the first reflector, and wherein one of the first and second
antennas is positioned between the plurality of directors and the
first reflector.
14. The antenna apparatus of claim 13, wherein the plurality of
directors are arranged so that the respective distance between
adjacent directors decreases between successive pairs of directors
starting from the distance between the first of the plurality of
directors immediately adjacent to one of the first and second
antennas.
15. The antenna apparatus of claim 13, wherein the plurality of
directors are arranged so that the respective distance between
adjacent directors increases starting from the distance between the
first of the plurality of directors immediately adjacent to one of
the first and second antennas.
16. The antenna apparatus of claim 13, wherein the plurality of
directors are configured so that the length of a particular
director is shorter than the immediately adjacent director starting
from the first of the plurality of directors immediately adjacent
to one of the first and second antennas.
17. The antenna apparatus of claim 13, wherein the plurality of
directors are configured so that the length of a particular
director is longer than the immediately adjacent director starting
from the first of the plurality of directors immediately adjacent
to one of the first and second antennas.
18. The antenna apparatus of claim 1, further comprising: a second
dielectric layer disposed on the second face of the
electromagnetically reflective layer; and a second arrangement of
conductors disposed on the second dielectric layer, the second
arrangement of conductors comprising: a second resonator including
a third antenna having a respective feed point, a third antenna
having a respective feed point, and a second coupling element
electrically connecting the respective feed points of the third and
fourth antennas; and a second reflector electrically isolated from
the second resonator and positioned adjacent to at least one of the
third and fourth antennas, and wherein a longitudinal axis of the
second reflector intersects the second coupling element.
19. The antenna apparatus of claim 18, further comprising: a
conductive via extending through the first dielectric layer, the
electromagnetically reflective layer and the second dielectric
layer, the conductive via electrically connecting the first and
second coupling elements; and a dielectric separator interposed
between the electromagnetically reflective layer and the via
electrically isolating the electromagnetically reflective layer and
the via.
20. An antenna apparatus comprising: an electromagnetically
reflective layer; a dielectric layer on the electromagnetically
reflective layer; a plurality of antennas arranged on the
dielectric layer in a respective plurality of directions, each of
the plurality of antennas having a feed point; at least one
coupling element, wherein each coupling element electrically
connects the respective feed points of a respective pair of
antennas; and at least one reflector electrically isolated from the
plurality of antennas and positioned adjacent to at least one of
the plurality of antennas, and wherein a respective longitudinal
axis of the at least one reflector intersects the first coupling
element.
21. The antenna apparatus of claim 19, wherein each of the
plurality of antennas is a folded dipole antenna, and the
respective feed point for each antenna comprises first and second
feed terminals, and wherein each coupling element includes first
and second conductive traces, the first conductive trace
electrically connecting the respective first feed terminals of a
pair of antennas, and the second conductive trace electrically
connecting the respective second feed terminals of the same pair of
antennas.
Description
CLAIM OF PRIORITY UNDER 35 U.S.C. .sctn.119
[0001] This application claims the benefit under 35 U.S.C.
.sctn.119(e) of U.S. Provisional Patent Application No. 61/243,120,
entitled "PORTABLE PASSIVE REPEATER," filed Sep. 16, 2009, and U.S.
Provisional Patent Application No. 61/373,222, entitled "PASSIVE
REPEATER WITH FLEXIBLE ELEMENTS," filed Aug. 12, 2010. The entire
contents of each of the above-identified provisional patent
applications are incorporated by reference herein and made part of
this specification.
BACKGROUND
[0002] 1. Field
[0003] This disclosure relates to wireless communications and to
passive repeaters for wireless communications.
[0004] 2. Description of Related Art
[0005] Growing demand for high-rate wireless data services
continues to drive the growth of wireless networks. One factor
fostering the rapid growth of wireless networks is the growing
demand for high-rate data services to be accessible from virtually
any location, at all times.
[0006] However, despite the efforts of network operators and
consumer equipment makers to provide seamless wireless
communication coverage, areas of weak signal strength still exist,
even in richly serviced areas such as urban centers. The areas of
weak signal strength, sometimes referred to as null spots or dead
spots, are sometimes caused by the density and material composition
of vehicles, buildings and other structures in a wireless coverage
area. For example, within a substantially enclosed environment,
such as a vehicle or building, the materials of the vehicle or
building can cause shadowing, shielding and/or multipath
interference that deteriorate radio frequency (RF) signals.
[0007] In a vehicle or building, for example, the metal body and/or
frame of a vehicle or structural metal and/or reflective windows of
a building creates a shielding effect that attenuates radio signals
within the vehicle or building. In a dense urban area, the
surrounding buildings create a multipath environment where signal
reflections destructively combine in locations that are difficult
to predict. The destructive interference reduces receivable RF
signals to the point where wireless communication can be virtually
impossible at the frequency and power levels used in the wireless
system. In other situations, the structures themselves acts as
barriers that significantly attenuate signal strength of RF signals
to the point where the RF signal strength within the structure is
lower than is desirable for reliable service.
SUMMARY
[0008] Various embodiments of systems, methods and devices within
the scope of the appended claims have several aspects, no single
one of which is solely responsible for the desirable attributes
described herein. Without limiting the scope of the appended
claims, some features are described. After considering this
discussion, and particularly after reading the section entitled
"Detailed Description," one will understand how the features of
various embodiments are used to configure a passive antenna
repeater.
[0009] There lies a challenge to provide increased RF signal
strength within and around vehicles, buildings and/or other
structures, so that wireless data services can be accessed
seamlessly throughout a coverage area.
[0010] In some embodiments, an antenna apparatus includes an
electromagnetically reflective layer plane, the electromagnetically
reflective layer having first and second faces; a first dielectric
layer disposed on the first face of the electromagnetically
reflective layer; and a first arrangement of conductors disposed on
the first dielectric layer. The first arrangement of conductors can
include a first resonator including a first antenna having a
respective feed point, a second antenna having a respective feed
point, and a first coupling element electrically connecting the
respective feed points of the first and second antennas. The first
arrangement of conductors can include a first reflector
electrically isolated from the first resonator and positioned
adjacent to at least one of the first and second antennas. The
longitudinal axis of the first reflector can intersect the first
coupling element.
[0011] In some embodiments, the first and second antennas are
folded dipole antennas. The respective feed point for each of the
first and second antennas comprises first and second feed
terminals. Additionally, the coupling element includes first and
second conductive traces, the first conductive trace electrically
connecting the respective first feed terminals of the first and
second antennas, and the second conductive trace electrically
connecting the respective second feed terminals of the first and
second antennas. In some embodiments, at least one of the first and
second antennas includes an undulating portion.
[0012] In some embodiments, the first arrangement of conductors
also includes a second reflector electrically isolated from the
first resonator and positioned adjacent to the second antenna. The
longitudinal axis of the second reflector can intersect the first
coupling element. In that embodiment, the first reflector is
positioned adjacent to the first antenna.
[0013] In some embodiments, the antenna apparatus includes a second
dielectric layer disposed on the second face of the
electromagnetically reflective layer; and a second arrangement of
conductors disposed on the second dielectric layer. The second
arrangement of conductors includes a second resonator including a
third antenna having a respective feed point, a third antenna
having a respective feed point, and a second coupling element
electrically connecting the respective feed points of the third and
fourth antennas; and a second reflector electrically isolated from
the second resonator and positioned adjacent to at least one of the
third and fourth antennas, and wherein the longitudinal axis of the
second reflector intersects the second coupling element.
[0014] In some embodiments, the antenna apparatus includes a
conductive via extending through the first dielectric layer, the
electromagnetically reflective layer and the second dielectric
layer, the conductive via electrically connecting the first and
second coupling elements; and a dielectric separator interposed
between the electromagnetically reflective layer and the via
electrically isolating the electromagnetically reflective layer and
the via.
[0015] One aspect of the disclosure is an antenna apparatus
including a electromagnetically reflective layer; a dielectric
layer on the electromagnetically reflective layer; a plurality of
antennas arranged on the dielectric layer in a respective plurality
of directions, each of the plurality of antennas having a feed
point; at least one coupling element, wherein each coupling element
electrically connects the respective feed points of a respective
pair of antennas; and at least one reflector electrically isolated
from the plurality of antennas and positioned adjacent to at least
one of the plurality of antennas, and wherein the respective
longitudinal axis of at least one reflector intersects the first
coupling element.
[0016] In some embodiments, each of the plurality of antennas is a
folded dipole antenna, and the respective feed point for each
antenna comprises first and second feed terminals, and wherein each
coupling element includes first and second conductive traces, the
first conductive trace electrically connecting the respective first
feed terminals of a pair of antennas, and the second conductive
trace electrically connecting the respective second feed terminals
of the same pair of antennas.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1A is a plan view of one embodiment of an antenna
apparatus.
[0018] FIG. 1B is a cross-sectional view of the antenna apparatus
of FIG. 1A taken along line A-A.
[0019] FIG. 1C is the plan view of the antenna apparatus of FIG. 1A
illustrated with an approximation of the radiation pattern of the
antenna apparatus.
[0020] FIG. 1D is the cross-sectional view of the antenna apparatus
of FIG. 1B shown with an approximation of the radiation pattern of
the antenna apparatus.
[0021] FIG. 2A is a cross-sectional view of one embodiment of an
antenna apparatus.
[0022] FIG. 2B is a plan view of the antenna apparatus of FIG.
2A.
[0023] FIG. 3 is a plan view of one embodiment of an antenna
apparatus illustrated with an approximation of the radiation
pattern of the antenna apparatus.
[0024] FIG. 4 is a plan view of one embodiment of an antenna
apparatus.
[0025] FIG. 5 is a plan view of one embodiment of an antenna
apparatus.
[0026] FIG. 6 is a plan view of one embodiment of an antenna
apparatus.
[0027] FIG. 7 is a plan view of one embodiment of an antenna
apparatus.
[0028] FIG. 8 is a plan view of one embodiment of an antenna
apparatus.
[0029] The various features illustrated in the drawings may not be
drawn to scale. Accordingly, the dimensions of the various features
may be arbitrarily expanded or reduced for clarity. In addition,
some of the drawings may not depict all of the components of a
given system, method or apparatus. Finally, like reference numerals
may be used to denote like features throughout the specification
and figures.
DETAILED DESCRIPTION
[0030] Various aspects of embodiments within the scope of the
appended claims are described below. It should be apparent that the
aspects described herein may be embodied in a wide variety of forms
and that any specific structure and/or function described herein is
merely illustrative. Based on the present disclosure one skilled in
the art should appreciate that an aspect described herein may be
implemented independently of any other aspects and that two or more
of these aspects may be combined in various ways. For example, an
apparatus may be implemented and/or a method may be practiced using
any number of the aspects set forth herein. In addition, such an
apparatus may be implemented and/or such a method may be practiced
using other structure and/or functionality in addition to or other
than one or more of the aspects set forth herein.
[0031] Some embodiments provide a relatively small antenna
apparatus that acts as a passive repeater. The antenna apparatus
can be designed to facilitate radio frequency (RF) signal gain for
a collection or range of frequencies. Some embodiments are
configured to be used with mobile phone networks (e.g., networks
operating at 1.920 GHz or other frequencies), wireless data
networks (e.g., Wi-Fi networks operating at 2.4 GHz and/or 5.8
GHz), other frequencies, or combinations of frequencies. In some
embodiments, the antenna apparatus is placed within a short range,
such as, for example, a distance of about 6-24 inches, of a device
with a wireless receiver and/or transmitter, where the antenna
apparatus causes increased RF signal intensity at the device by
coupling RF signals from a proximate area of higher RF signal
intensity into the area around the device. Other configurations and
ranges are possible, and, in some embodiments, increased RF signal
intensity can extend over larger distances. Accordingly, in some
instances, an embodiment of the antenna apparatus can be used to
increase the RF signal intensity in a null spot or dead spot by
coupling RF signal energy from an area proximate to the null spot
that has higher RF signal intensity.
[0032] FIG. 1A is a plan view of an antenna apparatus 100, and FIG.
1B is a cross-sectional view of the antenna apparatus 100 in FIG.
1A taken along line A-A. The antenna apparatus 100 illustrated in
FIGS. 1A and 1B includes an electromagnetically reflective layer
106, a dielectric layer 105 disposed adjacent to the
electromagnetically reflective layer 106, and an arrangement of
conductors disposed on the dielectric layer 105. In the illustrated
embodiment, the dielectric layer 105 is disposed between the
arrangement of conductors and the electromagnetically reflective
layer 106. As described in further detail below, the arrangement of
conductors includes a resonator 104 and a reflector comprising
first and second portions 101a, 101b.
[0033] In some embodiments, the electromagnetically reflective
layer 106 includes a rigid conductive plate. For example, the
conductive plate can be, without limitation, a plate of aluminum,
copper, another metal, a metal alloy, conductive ceramic, a
conductive composite material having a thickness sufficient to be
substantially rigid, another suitable material, or a combination of
materials. In some embodiments, the electromagnetically reflective
layer 106 is flexible. For example, the electromagnetically
reflective layer 106 can be, without limitation, a plate of
aluminum, copper, another metal, a metal alloy, a conductive
ceramic and/or a conductive composite material having a thickness
sufficient to be substantially flexible. Additionally, the
composite material may include a conductive thread including one or
more metals and/or metal alloys woven to form a plane or sheet.
Additionally and/or alternatively, the electromagnetically
reflective layer can be a heterogeneous structure including a
combination of dielectric and conductive portions, but nevertheless
remaining substantially reflective to electromagnetic energy.
[0034] The resonator 104 includes first and second antennas 103a,
103b electrically connected by a coupling element. For the sake of
facilitating the present description only, the coupling element is
labeled as having two portions 102a, 102b. In the antenna apparatus
100, the two portions of the coupling element 102a, 102b can be
arranged so as to be collinear, forming a straight conductive path
between the first and second antennas 103a, 103b.
[0035] The reflector includes first and second portions 101a, 101b
separated by a gap through which the coupling element extends and
intersects the longitudinal axis of the reflector. In some
embodiments, the reflector is a single conductor (not shown), and
the antenna apparatus 100 further includes a dielectric separator
(not shown) between the reflector and the coupling element. The
dielectric separator is provided to electrically isolate the
reflector and the coupling element. In other words the dielectric
separator prevents the reflector from shorting to the coupling
element.
[0036] The first and second antennas 103a, 103b are folded dipole
antennas, and the respective feed point of each of the first and
second antennas 103a, 103b includes respective first and second
feed terminals. Accordingly, the two portions of the coupling
element 102a, 102b include first and second parallel conductive
traces. The first conductive trace electrically connects the
respective first feed terminals of the first and second antennas
103a, 103b. The second conductive trace electrically connects the
respective second feed terminals of the first and second antennas
103a, 103b.
[0037] Each of the first and second folded dipole antennas 103a,
103b is defined by a length L.sub.1. The tips of a folded dipole
antenna are folded back until they almost meet at the feed point,
such that the antenna comprises one entire wavelength. Accordingly,
so long as the first and second feed point terminals are
sufficiently close to one another, the wavelength of each of the
first and second folded dipole antennas 103a, 103b is 2L.sub.1.
Those skilled in the art will appreciate that this arrangement has
a greater bandwidth than a standard half-wave dipole. Moreover, the
length of each of the first and second portions of the reflector
101a, 101b is length L.sub.4, which is approximately 1/2L.sub.1.
However, while the first and second reflector portions 101a, 101b
are approximately the same length in FIG. 1A, in other embodiments,
the first and second reflector portions 101a, 101b are different
lengths. The lengths of the first and second antennas can be used
to determine the dimensions of the antenna apparatus 100.
[0038] For example, some embodiments are configured to be used with
mobile phone networks (e.g., networks operating at 1.920 GHz or
other frequencies), wireless data networks (e.g., Wi-Fi networks
operating at 2.4 GHz and/or 5.8 GHz), other frequencies, or
combinations of frequencies. As such, the wavelengths associated
with such frequencies could be used to define L.sub.1, as being a
quarter, a half or full wavelength associated with the center
frequency of the band.
[0039] Additionally, the first folded dipole antenna 103a is spaced
from the reflector portions 101a, 101b by a distance d.sub.2, and
the second folded dipole antenna 103b is spaced from the reflector
portions 101a, 101b by a distance d.sub.3. The distances d.sub.2,
d.sub.3 can be equal or different. However, those skilled in the
art will appreciate that an asymmetric spacing will have an impact
on the radiation pattern of the antenna apparatus 100.
[0040] While the first and second antennas 103a, 103b illustrated
in FIG. 1A are folded dipole antennas those skilled in the art will
appreciate from the present disclosure that the first and second
antennas 103a, 103b can be each individually configured, without
limitation, as one of a monopole antenna, a dipole antenna, a
rhombic antenna, a planar antenna, and a yagi antenna. Those
skilled in the art will appreciate that the radiation pattern of
the resulting antenna apparatus will change as a function of the
antenna types chosen for the respective first and second antennas
103a, 103b.
[0041] FIG. 1C is the plan view of the antenna apparatus 100 of
FIG. 1A illustrated with an approximation of the radiation pattern
of the antenna apparatus. Similarly, FIG. 1D is the cross-sectional
view of the antenna apparatus 100 shown with a cross-sectional view
of the same approximation of the radiation pattern of the antenna
apparatus 100. With reference to both FIGS. 1C and 1D, the
reflector portions 101a, 101b distort the toriodal radiation
patterns of the first and second folded dipole antennas 103a, 103b.
For the first folded dipole antenna 103a the result is a radiation
pattern approximated by the dashed line 110a in FIGS. 1C and 1D.
For the second folded dipole antenna 103b the result is a radiation
pattern approximated by the dashed line 110b in FIGS. 1C and 1D. In
operation, RF signals received by one of the antennas are coupled
through the coupling element and propagated by through the
respective radiation pattern of the other.
[0042] FIGS. 2A and 2B provide views of an antenna apparatus 200.
The antenna apparatus 200 illustrated in FIGS. 2A and 2B is similar
to and adapted from the antenna apparatus 100 illustrated in FIG.
1A. Accordingly, elements common to both antenna apparatus 100 and
200 share common reference indicia, and only differences between
the antenna apparatus 100 and 200 are described herein for the sake
of brevity. However, for the sake of facilitating the description
only, the dielectric layer 105 shown in FIGS. 1A-1D has been
relabeled as the first dielectric layer 105a in FIGS. 2A-2B.
[0043] More specifically, FIG. 2A is a cross-sectional view the
antenna apparatus 200, and FIG. 2B is a plan view of the antenna
apparatus 200. In addition to the elements illustrated in FIGS.
1A-1B, the antenna apparatus illustrated in FIGS. 2A-2B includes a
second dielectric layer 105b on the second face of the
electromagnetically reflective layer 106, and an arrangement of
conductors on the second dielectric layer 105b. The arrangement of
conductors on the second dielectric layer 105b includes a resonator
108 and a reflector comprising first and second portions 101c,
101d.
[0044] In some embodiments, the antenna apparatus 200 additionally
includes an optional conductive via 120 extending through the first
dielectric layer 105a, the electromagnetically reflective layer 106
and the second dielectric layer 105b. The conductive via 120
electrically connects the first and second coupling elements.
Additionally, a dielectric separator is interposed between the
electromagnetically reflective layer 106 and the conductive via 120
in order to electrically isolate one from the other.
[0045] The resonator 108 includes third and fourth antennas 103c,
103d electrically connected by a coupling element. For the sake of
facilitating the present description only, the coupling element is
labeled as having two portions 102c, 102d. In the antenna apparatus
200 the two portions of the coupling element 102c, 102d are
arranged so as to be collinear forming a straight conductive path
between the third and fourth antennas 103c, 103d.
[0046] The reflector includes first and second portions 101c, 101d
separated by a gap through which the coupling element extends and
intersects the longitudinal axis of the reflector. In some
embodiments, the reflector is a single conductor (not shown), and
the antenna apparatus 200 further includes a dielectric separator
(not shown) between the reflector and the coupling element. The
dielectric separator is provided to electrically isolate the
reflector and the coupling element. In other words the dielectric
separator prevents the reflector from shorting to the coupling
element.
[0047] The third and fourth antennas 103c, 103d are folded dipole
antennas, and the respective feed point of each of the third and
fourth antennas 103c, 103d includes respective first and second
feed terminals. Accordingly, the two portions of the coupling
element 102c, 102d include first and second parallel conductive
traces. The first conductive trace electrically connects the
respective first feed terminals of the third and fourth antennas
103c, 103d. The second conductive trace electrically connects the
respective second feed terminals of the third and fourth antennas
103c, 103d.
[0048] Those skilled in the art will recognize from the present
disclosure and drawings that the respective arrangements of
conductors on the respective first and second dielectric layers
105a, 105b are substantially identical. The resulting radiation
pattern for the antenna apparatus 200 is therefore substantially
symmetric. In particular, the radiation pattern of the created by
the reflector portions 101c, 101d and the third and fourth antennas
103c, 103d being the substantial mirror image of the radiation
pattern created by the reflector portions 101a, 101b and the first
and second antenna 103a, 103b.
[0049] FIG. 2A shows a cross-sectional view of an approximation of
the radiation pattern for the antenna apparatus 200. The reflector
portions 101a, 101b distort the toroidal radiation patterns of the
first and second folded dipole antennas 103a, 103b. The reflector
portions 101c, 101d distort the toroidal radiation patterns of the
third and fourth folded dipole antennas 103c, 103d. For the first
folded dipole antenna 103a the result is a radiation pattern
approximated by the dashed line 110a. For the second folded dipole
antenna 103b the result is a radiation pattern approximated by the
dashed line 110b. For the third folded dipole antenna 103c the
result is a radiation pattern approximated by the dashed line 110c.
For the fourth folded dipole antenna 103d the result is a radiation
pattern approximated by the dashed line 110d. In operation, RF
signals received by one of the antennas are coupled through the
coupling element and propagated by through the respective radiation
pattern of the other. The via 120 allows signal energy to be
received on one side of the electromagnetically reflective layer
106 and propagated through the radiation patterns of the respective
antennas on the other side of the electromagnetically reflective
layer 106.
[0050] Those skilled in the art will also appreciate from the
present disclosure that the respective arrangements of conductors
do not have to be substantially identical, and can instead be
configured in any number of ways in order to create different
radiation patterns for one or more of the first, second, third and
fourth antennas.
[0051] FIG. 3 is a plan view of an antenna apparatus 300
illustrated with an approximation of its radiation pattern. The
antenna apparatus 300 illustrated in FIG. 3 is similar to and
adapted from the antenna apparatus 100 illustrated in FIG. 1A.
Accordingly, elements common to both antenna apparatus 100 and 300
share common reference indicia, and only differences between the
antenna apparatus 100 and 300 are described herein for the sake of
brevity.
[0052] With reference to FIG. 3 the first arrangement of conductors
additionally includes first and second director elements 142, 141.
The first director 142 is positioned adjacent the first folded
dipole antenna 103a, such that the first folded dipole antenna 103a
is between the reflector portions 101a, 101b and the first director
142. The second director 141 is positioned adjacent the second
folded dipole antenna 103b, such that the second folded dipole
antenna 103b is between the reflector portions 101a, 101b and the
second director 141. While the antenna apparatus 300 includes a
director element adjacent each of the first and second antennas
103a, 103b, in another embodiment an antenna apparatus includes a
single director adjacent one of the first and second antennas. In
such an embodiment, the radiation pattern will be different from
the approximated radiation pattern illustrated in FIG. 3. In
another embodiment, an antenna apparatus includes multiple
directors adjacent one of the first and second antennas.
[0053] As compared to the approximated radiation pattern
illustrated in FIG. 1C, the first and second directors 142, 141 of
FIG. 3 elongate the radiation pattern on either side of the
reflector portions 101a, 101b. For the first folded dipole antenna
103a the result is an elongated radiation pattern approximated by
the dashed line 110a.sub.1. For the second folded dipole antenna
103b the result is an elongated radiation pattern approximated by
the dashed line 110b.sub.1.
[0054] FIG. 4 is a plan view of an antenna apparatus 400, in which
only the arrangement of conductors disposed on the dielectric layer
is shown. The antenna apparatus 400 illustrated in FIG. 4 is
similar to and adapted from the antenna apparatus 100 illustrated
in FIG. 1A. Accordingly, elements common to both antenna apparatus
100 and 400 share common reference indicia, and only differences
between the antenna apparatus 100 and 400 are described herein for
the sake of brevity.
[0055] With reference to FIG. 4, the arrangement of conductors
additionally includes a plurality of directors 142a, 142b, 142c
parallel to the reflector portions 101a, 101b, and positioned such
that the first folded dipole antenna 103a is between the plurality
of directors 142a, 142b, 142c and the reflector portions 101a,
101b. Additionally, the arrangement of conductors additionally
includes a plurality of directors 141a, 141b, 141c parallel to the
reflector portions 101a, 101b, and positioned such that the second
folded dipole antenna 103b is between the plurality of directors
141a, 141b, 141c and the reflector portions 101a, 101b. While only
three directors are shown with each antenna in FIG. 4, those
skilled in the art will appreciate that an antenna can be provided
with any number of directors or even no directors at all. Moreover,
each antenna may include more or less directors than other antennas
in the same apparatus.
[0056] The respective distances between the directors can be varied
to change the radiation pattern of the antenna apparatus 400.
Examples are described in further detail below with further
reference to FIG. 4, in which the distances d.sub.1, d.sub.2, and
d.sub.3 correspond to the respective distance between the second
folded dipole antenna 103b and the director 141a, the respective
distance between the directors 141a, 141b, and the respective
distance between the directors 141b, 141c.
[0057] The respective lengths of the directors can be varied to
change the bandwidth of the antenna apparatus 400. Examples are
described in further detail below with further reference to FIG. 4,
in which the lengths L.sub.0, L.sub.1, L.sub.2, and L.sub.3
correspond to the length of the second folded dipole antenna 103b,
the director 141a, the director 141b, and the director 141c,
respectively.
[0058] In some embodiments, the plurality of directors are arranged
so that the respective distance between adjacent directors
decreases between successive pairs of directors starting from the
distance between the first of the plurality of directors
immediately adjacent to one of the first and second antennas. For
example, with further reference to FIG. 4, when the distances
d.sub.1, d.sub.2, and d.sub.3 are such that d.sub.1<d.sub.2,
<d.sub.3 the radiation pattern of the second folded dipole
antenna 103b bulges outward parallel to the longitudinal axis of
the reflector portions 101a, 101b.
[0059] In some embodiments, the plurality of directors are arranged
so that the respective distance between adjacent directors
increases starting from the distance between the first of the
plurality of directors immediately adjacent to one of the first and
second antennas. For example, with further reference to FIG. 4,
when the distances d.sub.1, d.sub.2, and d.sub.3 are such that
d.sub.1>d.sub.2, >d.sub.3 the radiation pattern of the second
folded dipole antenna 103b elongates in a manner similar to the
radiation pattern 110b.sub.1 illustrated in FIG. 3.
[0060] In some embodiments, the plurality of directors are
configured so that the length of a particular director is shorter
than the immediately adjacent director starting from the first of
the plurality of directors immediately adjacent to one of the first
and second antennas. For example, with further reference to FIG. 4,
when the lengths L.sub.1, L.sub.2, and L.sub.3 are such that
L.sub.1<L.sub.2, <L.sub.3 the radiation pattern of the second
folded 103b dipole antenna increases on the higher frequency end of
the bandwidth.
[0061] In some embodiments, the plurality of directors are
configured so that the length of a particular director is longer
than the immediately adjacent director starting from the first of
the plurality of directors immediately adjacent to one of the first
and second antennas. For example, with further reference to FIG. 4,
when the lengths L.sub.1, L.sub.2, and L.sub.3 are such that
L.sub.1>L.sub.2, >L.sub.3 the bandwidth of the second folded
dipole antenna 103b increases on the lower frequency end of the
bandwidth.
[0062] FIG. 5 is a plan view of an antenna apparatus 500, in which
only the arrangement of conductors disposed on the dielectric layer
is shown. The antenna apparatus 500 illustrated in FIG. 5 is
similar to and adapted from the antenna apparatus 100 illustrated
in FIG. 1A. Accordingly, elements common to both antenna apparatus
100 and 500 share common reference indicia, and only differences
between the antenna apparatus 100 and 500 are described herein for
the sake of brevity.
[0063] In contrast to FIG. 1A, with reference to FIG. 5, the two
portions of the coupling element 102a, 102b meet at a corner and
the first and second antennas 103a, 103b are arranged facing
respective first and second directions. While the two portions of
the coupling element 102a, 102b are illustrated as being
perpendicular to one another, those skilled in the art will
appreciate from the present disclosure that the two portions of the
coupling element 102a, 102b can be arranged at any angle in order
to customize the radiation pattern of the antenna apparatus.
[0064] Additionally, the antenna apparatus 500 includes two
reflectors. The first reflector includes portions 151a, 151b
separated by a gap through which the first coupling element portion
102a extends and intersects the longitudinal axis of the first
reflector. The second reflector includes portions 151c, 151d
separated by a gap through which the second coupling element
portion 102b extends and intersects the longitudinal axis of the
second reflector.
[0065] Additionally, the distance between the reflector portions
151a, 151b and the corner is d.sub.2, and the distance between the
reflector portions 151c, 151d and the corner is d.sub.3. The
distances d.sub.2, d.sub.3 can be equal or different.
[0066] FIG. 6 is a plan view of an antenna apparatus 600, in which
only the arrangement of conductors disposed on the dielectric layer
is shown. The antenna apparatus 600 illustrated in FIG. 6 is
similar to and adapted from the antenna apparatus 100 illustrated
in FIG. 1A. Accordingly, elements common to both antenna apparatus
100 and 600 share common reference indicia, and only differences
between the antenna apparatus 100 and 600 are described herein for
the sake of brevity.
[0067] With reference to FIG. 6, the first folded dipole antenna
103a includes an undulating portion 106a. The undulating portion
106a is duplicated by the director 161a such that the distance
d.sub.9 between corresponding points on the undulating portion 106a
and the director 161a is substantially constant along the length of
each. Similarly, the second folded dipole antenna 103b includes an
undulating portion 106b. The undulating portion 106b is duplicated
by the director 161b such that the distance d.sub.10 between
corresponding points on the undulating portion 106b and the
director 161b is substantially constant along the length of each.
The undulating portions 106a, 106b allow the antenna apparatus to
be scaled down while substantially preserving the defining
wavelengths of the first and second folded dipole antennas 103a,
103b. While only one director is shown with each antenna in FIG. 6,
those skilled in the art will appreciate that an antenna can be
provided with any number of directors or even no directors at all.
For example, each dipole antenna 103a, 103b shown in FIG. 6 can
include two directors. Moreover, each antenna may include more or
less directors than other antennas in the same apparatus.
[0068] Moreover, in some embodiments, the curvature of the
undulations is configured to reduce the concentration of RF energy
at inflection points where the metal traces change directions. By
contrast, those skilled in the art will appreciate from the present
disclosure that sharp corners (e.g. creating a zig-zag) pattern
would result in a concentration of RF energy at the corners, which
thereby substantially changes the density of RF energy along the
length of the first and second antennas and/or the director
elements.
[0069] FIG. 7 is a plan view of an antenna apparatus 700, in which
only the arrangement of conductors disposed on the dielectric layer
is shown. The arrangement of conductors includes folded dipole
antennas 703a, 703b, 703c, 703d, 703e, 703f, reflector portions
701a, 701b, 701c, 701d, 701e, 701f, 701g, 701h, 701i, 701j, 701k,
701l, and conductive traces 702a, 702b, 702c, 702d, 702e, 702f Each
folded dipole antenna 703a, 703b, 703c, 703d, 703e, 703f is
provided with an adjacent plurality of directors. For example, the
folded dipole antenna 703a is provided with directors 741a, 741b,
741b. While only three directors are shown in FIG. 7, those skilled
in the art will appreciate that an antenna can be provided with any
number of directors or even no directors at all. Moreover, each
antenna may include more or less directors than other antennas in
the same apparatus.
[0070] The folded dipole antennas 703a, 703b, 703c, 703d, 703e,
703f are arranged in a hexagonal approximation of a circle. Each of
the folded dipole antennas 703a, 703b, 703c, 703d, 703e, 703f is
paired with one adjacent antenna. Specifically, antennas 703a and
703b are paired, antennas 703c and 703d are paired, and antennas
703e and 703f are paired. The result is that the radiation pattern
formed by a pair of antennas approximates a bent pipe from one side
of the arrangement of antennas to an adjacent side, such that
signals received on one side are propagated from the adjacent
side.
[0071] Conductive traces 702a, 702b electrically connect the
respective first and second feed terminals of the antennas 703a,
703b. Conductive traces 702c, 702d electrically connect the
respective first and second feed terminals of the antennas 703c,
703d. Conductive traces 702e, 702f electrically connect the
respective first and second feed terminals of the antennas 703e,
703f.
[0072] The conductive traces 702a, 702b extend through a gap
separating reflector portions 701a, 701b. The conductive traces
702a, 702b also extend through a gap separating reflector portions
701c, 701d. The conductive traces 702c, 702d extend through a gap
separating reflector portions 701e, 701f. The conductive traces
702c, 702d also extend through a gap separating reflector portions
701g, 701h. The conductive traces 702e, 702f extend through a gap
separating reflector portions 701i, 701j. The conductive traces
702e, 702f also extend through a gap separating reflector portions
701k, 701l.
[0073] FIG. 8 is a plan view of an antenna apparatus 800, in which
only the arrangement of conductors disposed on the dielectric layer
is shown. The antenna apparatus 800 illustrated in FIG. 8 is
similar to and adapted from the antenna apparatus 700 illustrated
in FIG. 7. Accordingly, elements common to both antenna apparatus
700 and 800 share common reference indicia, and only differences
between the antenna apparatus 700 and 800 are described herein for
the sake of brevity.
[0074] As compared to the antenna apparatus 700, each of the folded
dipole antennas 703a, 703b, 703c, 703d, 703e, 703f is respectively
electrically paired and connected to the corresponding folded
dipole antenna diametrically opposite a particular one of the
folded dipole antennas. Specifically, antennas 703a and 703d are
electrically coupled by parallel conductive traces 702a, 702b,
antennas 703b and 703e are electrically coupled by parallel
conductive traces 702e, 702f, and antennas 703c and 703f are
electrically coupled by parallel conductive traces 702c, 702d. The
conductive traces 702e, 702f electrically coupled to antennas 703b,
703e are partially hidden to simplify the view in FIG. 8; those
traces 702e, 702f are configured to electrically couple the
antennas 703b, 703e despite a portion of the traces 702e, 702f not
being shown. The result is that the radiation pattern formed by a
pair of antennas approximately extends from one side of the
arrangement of antennas through to a diametrically opposite side,
such that signals received on one side are propagated from the
diametrically opposite side.
[0075] Additionally and/or alternatively, an embodiment of antenna
apparatus can be combined with a user interface. The user interface
may include a detector circuit and a user-readable display, such as
a series of diodes or a liquid crystal display. In some
embodiments, the detector circuit is coupled between the resonant
structure of an antenna apparatus and the user interface. The
detector circuit can be configured to draw off a small portion of
RF signal energy received by one or more of the antennas in
operation. The detector can provide a signal to the user interface
according to how much RF signal energy is detected. For example,
the detector can be configured to detect RF signal energy in
relation to two or more threshold levels. If RF signal energy is
lower than a first threshold level, the detector signals that the
RF signal energy is very weak or non-existent. If RF signal energy
is between the first and second threshold levels, the detector
signals that the RF signal energy is low. If RF signal energy is
higher than the second threshold level, the detector signals that
the RF signal energy is strong. In response to receiving the
detector signal, the user interface provides a corresponding user
readable output that can be interpreted by a user. The user
readable output can include one or more visual indicators,
displays, lamps, other output devices, or a combination of devices.
In some embodiments, the user interface and/or the detector circuit
can be disposed in a single housing that also contains the antenna
apparatus.
[0076] The above description is provided to enable any person
skilled in the art to make or use embodiments within the scope of
the appended claims. Various modifications to these aspects will be
readily apparent to those skilled in the art, and the generic
principles defined herein may be applied to other aspects without
departing from the scope of the disclosure. Thus, the present
disclosure is not intended to be limited to the aspects shown
herein but is to be accorded the widest scope consistent with the
principles and novel features disclosed herein.
* * * * *