U.S. patent application number 16/600150 was filed with the patent office on 2021-04-15 for n-channel high-power rf multiplexer.
This patent application is currently assigned to United States of America, as Represented by the Secretary of the Navy. The applicant listed for this patent is United States of America as represented by the Secretary of the Navy, United States of America as represented by the Secretary of the Navy. Invention is credited to Nazia Mozaffar, Daniel W. S. Tam, Frederick Verd, Tiaotiao Xie, Lu Xu.
Application Number | 20210111691 16/600150 |
Document ID | / |
Family ID | 1000005490289 |
Filed Date | 2021-04-15 |
United States Patent
Application |
20210111691 |
Kind Code |
A1 |
Xie; Tiaotiao ; et
al. |
April 15, 2021 |
N-Channel High-Power RF Multiplexer
Abstract
A method for reducing a quantity of cable runs to antennas can
include the step of providing a circuit of reactive elements
coupled between an input terminal and at least two output
terminals. The circuit can be used to separate a broadband signal
into two or more disjoint expected frequency ranges. The circuit
can match the impedance at the at least two output terminals to the
impedance expected by the antennas. The elements of the circuit can
have reactances and arrangement so that when a broadband RF signal
is applied at the input terminal, two or more disjoint expected
frequencies can be applied to the respective output terminals. The
power at each output terminal can sufficiently match the antennas'
expected power, and insertion losses can be minimized.
Inventors: |
Xie; Tiaotiao; (San Diego,
CA) ; Xu; Lu; (San Diego, CA) ; Verd;
Frederick; (San Diego, CA) ; Tam; Daniel W. S.;
(San Diego, CA) ; Mozaffar; Nazia; (San Diego,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
United States of America as represented by the Secretary of the
Navy |
San Diego |
CA |
US |
|
|
Assignee: |
United States of America, as
Represented by the Secretary of the Navy
Arlington
VA
|
Family ID: |
1000005490289 |
Appl. No.: |
16/600150 |
Filed: |
October 11, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01Q 5/335 20150115;
H01Q 1/02 20130101; H03H 7/461 20130101; H03H 7/0161 20130101; H03H
7/0115 20130101; H05K 1/162 20130101; H05K 1/025 20130101; H05K
1/0203 20130101; H01Q 5/50 20150115; H05K 1/0243 20130101 |
International
Class: |
H03H 7/46 20060101
H03H007/46; H03H 7/01 20060101 H03H007/01; H05K 1/02 20060101
H05K001/02; H01Q 5/335 20060101 H01Q005/335; H01Q 1/02 20060101
H01Q001/02; H01Q 5/50 20060101 H01Q005/50 |
Goverment Interests
FEDERALLY-SPONSORED RESEARCH AND DEVELOPMENT
[0001] The United States Government has ownership rights in this
invention. Licensing inquiries may be directed to Office of
Research and Technical Applications, Naval Information Warfare
Center, Pacific, Code 72120, San Diego, Calif., 92152; telephone
(619) 553-5118; email: ssc_pac_t2@navy.mil. Reference Navy Case No.
106,172.
Claims
1. A high-power multiplexer comprising: an input terminal
configured for receiving a signal at a first RF frequency range; at
least two inductive elements, wherein a first of the at least two
inductive elements is arranged in series with the input terminal; a
number of bandpass filters equal to the number of inductive
elements, each bandpass filter corresponding to, and electrically
connected in series to, one of the inductive elements, wherein each
bandpass filter has a respective frequency range and the bandpass
filter having the highest frequency range is arranged electrically
proximal in series with the first inductive element; wherein the at
least two bandpass filters are arranged by decreasing respective
higher frequency such that the bandpass filter with the highest
frequency is connected to the input terminal and each subsequent
bandpass filter is increasingly electrically distant to the input
terminal; and wherein a last of the at least two inductive elements
is arranged in series with a last bandpass filter having the lowest
top end; at least two output terminals, wherein the number of
output terminals is equal to the number of bandpass filters, and
each output terminal is arranged in series with one of the at least
two bandpass filters to comprise a respective filter block; and
wherein each subsequent pair of filters blocks are spaced apart by
one of the inductive elements, and each filter block is arranged in
parallel with a respective circuit block, wherein the respective
circuit block comprises: i) each other filter block that has a
lower bandpass higher frequency than said filter block, and ii)
respective inductive elements of said each other filter blocks.
2. The high-power multiplexer of claim 5, wherein each bandpass
filter of the at least two bandpass filters comprises a multi-stage
bandpass filter.
3. The high-power multiplexer of claim 2, wherein each bandpass
stage of each multi-stage bandpass filter comprises either an
inductive element arranged in series with a capacitive element and
further in series with a load comprising the respective output
terminal, or an inductive element arranged in parallel with a
capacitive element and further in parallel with a load comprising
the respective output terminal, and no bandpass stages of the same
type are adjacent.
4. The high-power multiplexer of claim 3, wherein each multi-stage
bandpass filter comprises an odd number of bandpass stages, and
reactances of elements of the stages are symmetric about a middle
stage in an ordered arrangement of stages; and the reactances of
the elements of the stages are selected such that the stages are
ordered with higher resonant frequencies arranged proximal to the
middle stage.
5. The high-power multiplexer of claim 4, wherein the a first
bandpass filter has a frequency range within 200 MHz to 460 MHz at,
a second bandpass filter has a frequency range within 100-195 MHz,
a third bandpass filter has a frequency range within 24 to 96 MHz,
and a fourth bandpass filter has a frequency range within 0.5-12
MHz.
6. The high-power multiplexer of claim 1, wherein the device is
disposed on a printed circuit board (PCB), and the inductance of
the at least two inductive elements is determined to minimize the
loss across conductive traces of the PCB from the input terminal to
each bandpass filter.
7. The high-power multiplexer of claim 6, wherein the inductance of
the at least two inductive elements is determined to match the
impedance across conductive traces of the PCB from the input
terminal to each bandpass filter.
8. The high-power multiplexer of claim 1, wherein the reactances of
the elements of the device are selected such that impedance at the
input terminal substantially matches the impedance of at least one
of the at least two output terminals.
9. The high-power multiplexer of claim 1, wherein the reactances of
the elements of the device are selected such that insertion losses
in the device are minimized.
10. A method for reducing a quantity of cable runs to antennas, the
method comprising the steps of: A) providing an input terminal, the
input terminal configured to receive a broadband RF signal from a
single input cable; B) providing at least two output terminals,
wherein each output terminal is configured to transmit output
signals to a respective antenna, and wherein the respective
antennas have certain i) impedances, ii) signal frequency ranges,
and iii) signal power for the output signals; C) providing a
circuit of reactive elements coupled between the input terminal and
the at least two output terminals, the circuit configured for
separating the broadband signal into two or more disjoint frequency
ranges, and further configured so that the circuit matches the
impedance of the at least two output terminals to the impedance of
each of the respective antennas; wherein the reactances and the
arrangement of reactive elements in the circuit are selected such
that when a broadband RF signal is applied at the input terminal,
each of the two or more disjoint certain frequency ranges are
applied at the respective output terminals while the impedance of
the circuit at each output terminal sufficiently matches the
certain output terminal impedance, the power at each output
terminal sufficiently matches the certain power and insertion
losses are minimized.
11. The method of claim 1, further comprising the step of: D)
providing a cooling element proximal to the reactive elements;
wherein the cooling element is configured as a cooling means
sufficient to minimize losses.
12. The method of claim 1, further comprising the steps of: E)
providing the single input cable coupled to the input terminal; F)
providing at least two output cables, wherein each output cable is
coupled between a respective output terminal and one of the
respective antennas; and, wherein the single input cable has a
length ten times or more than an average length of the output
cables.
13. The method of claim 1, wherein at least a portion of the
circuit of reactive elements comprises at least one arrangement
from the group consisting of a cochlear manifold bandpass circuit
or a cascading diplexer circuits.
14. A high-power radio frequency (RF) multiplexer comprising: a
first terminal; a first high pass filter having a first plurality
of inductive elements arranged in series between the first terminal
and a second terminal, and further having a first plurality of
capacitive elements connected in parallel with the first plurality
of inductive elements such that each connection point between two
inductive elements of the first plurality of inductive elements is
connected to a first end of a respective capacitive element and
second ends of each of the first plurality of capacitive elements
are electrically connected; and a first low pass filter having a
second plurality of capacitive elements arranged in series between
the first terminal and a third terminal, and further having a
second plurality of inductive elements connected in parallel with
the second plurality of capacitive elements such that each
connection point between two capacitive elements of the second
plurality of capacitive elements is connected to a first end of a
respective inductive element of the second plurality of inductive
elements and second ends of each of the second plurality of
inductive elements are electrically connected.
15. The high-power RF multiplexer of claim 14, wherein the high
pass filter and the low pass filter are bidirectional such that the
high-power RF multiplexer is capable of serving as a multiplexer or
as a demultiplexer.
16. The high-power RF multiplexer of claim 14, wherein the high
pass filter and the low pass filter are not connected to a power
source other than incoming RF energy.
17. The high-power RF multiplexer of claim 14, further comprising:
a second high pass filter having a third plurality of inductive
elements arranged in series between the third terminal and a fourth
terminal, and further having a third plurality of capacitive
elements connected in parallel with the third plurality of
inductive elements such that each connection point between two
inductive elements of the third plurality of inductive elements is
connected to a first end of a respective capacitive element and
second ends of each of the third plurality of capacitive elements
are electrically connected; and a second low pass filter having a
fourth plurality of capacitive elements arranged in series between
the third terminal and a fifth terminal, and further having a
fourth plurality of inductive elements connected in parallel with
the fourth plurality of capacitive elements such that each
connection point between two capacitive elements of the fourth
plurality of capacitive elements is connected to a first end of a
respective inductive element of the fourth plurality of inductive
elements and second ends of each of the fourth plurality of
inductive elements are electrically connected.
18. The high-power RF multiplexer of claim 14, wherein the first
and second pluralities of capacitive elements are integrated into a
printed circuit board dielectric substrate such that each
capacitive element has a first conductive layer deposited on a
first side of the dielectric substrate and a second conductive
layer deposited on an opposite side of the dielectric substrate so
as to provide a broadside coupling capacitance effect between the
first conductive layer and the second conductive layer.
19. The high-power RF multiplexer of claim 18, wherein the first
conductive layer and the opposite conductive layer have a
double-sided comb shape.
20. The high-power RF multiplexer of claim 19, wherein at least
each of a majority of the capacitive elements has a corresponding
cooling fin attached thereto so as to enable heat transfer away
from the capacitive element to which the corresponding cooling fin
is attached.
Description
BACKGROUND OF THE INVENTION
[0002] The present invention is generally drawn to a method and a
device for reducing the number of cable runs to antennas.
[0003] Antennas can be used in communications. Antennas can receive
and/or transmit messages by superimposing information (e.g. by
amplitude and/or frequency modulation) on carrier electromagnetic
waves, as is known in the art. Traditionally, the signals to/from
each antenna can be relayed to/from another part of the
communication system via a dedicated cable coupled to each of the
antennas (i.e., a dedicated cable run between the antenna and the
rest of the communication system, usually the console). The cables
can each be a radio frequency (RF) cable.
[0004] However, the arrangement in the prior art can become
problematic. Often time, the cable, which can be quite heavy and
must be run hundreds of feet from the antenna to the rest of the
system. As communication needs increase (communication needs rarely
decrease), more and more antennas are needed, which means more and
more cable runs are needed. This can increase the weight of the
hosting platform. For hosting platforms that are naval vessels, the
additional weight can be significant enough so that the center of
buoyancy is affected. Additionally, the cable must be run through
watertight bulkheads, which means that an opening in the bulkhead
must be formed, the cable run through the opening, and then the
opening must be made watertight again. This can be a tedious,
expensive endeavor, and the end result is typically not as
watertight as the original bulkhead. Meanwhile, mobile platforms
that have such antennas systems, can require communication systems
having greatly reduced weight, complexity, and points of failure.
Example mobile platforms can be mobile vehicles, submarines,
trains, ships, trucks, amphibious vehicles, flying vehicles, launch
vehicles, and/or satellites. Some have attempted to solve this
problem through the use of multiplexers. However prior art
multiplexers are unsuitable for high-power applications.
Accordingly, for at least the foregoing reasons, there exists a
need for an improved multiplexer.
SUMMARY OF THE INVENTION
[0005] Described herein is a high-power multiplexer, an embodiment
of which comprises an input terminal, at least two inductive
elements, a number of bandpass filters, and at least two output
terminals. The input terminal is configured for receiving a signal
at a first RF frequency range. A first of the at least two
inductive elements is arranged in series with the input terminal.
The number of bandpass filters is equal to the number of inductive
elements. Each bandpass filter corresponds to, and is electrically
connected in series to, one of the inductive elements. Each
bandpass filter has a respective frequency range and the bandpass
filter having the highest frequency range is arranged electrically
proximal in series with the first inductive element. The at least
two bandpass filters are arranged by decreasing respective higher
frequency such that the bandpass filter with the highest frequency
is connected to the input terminal and each subsequent bandpass
filter is increasingly electrically distant to the input terminal.
A last of the at least two inductive elements is arranged in series
with a last bandpass filter having the lowest top end. The number
of output terminals is equal to the number of bandpass filters, and
each output terminal is arranged in series with one of the at least
two bandpass filters to comprise a respective filter block. Each
subsequent pair of filters blocks are spaced apart by one of the
inductive elements, and each filter block is arranged in parallel
with a respective circuit block. The respective circuit block
comprises: i) each other filter block that has a lower bandpass
higher frequency than said filter block, and ii) respective
inductive elements of said each other filter blocks.
[0006] Also described herein is a method for reducing a quantity of
cable runs to antennas by using an embodiment of the high-power
multiplexer that comprises the following steps. The first step
provides for providing an input terminal, the input terminal
configured to receive a broadband RF signal from a single input
cable. Another step provides for providing at least two output
terminals. Each output terminal is configured to transmit output
signals to a respective antenna. The respective antennas have
certain i) impedances, ii) signal frequency ranges, and iii) signal
power for the output signals. Another step provides for providing a
circuit of reactive elements coupled between the input terminal and
the at least two output terminals. The circuit is configured for
separating the broadband signal into two or more disjoint frequency
ranges. The circuit is further configured so that the circuit
matches the impedance of the at least two output terminals to the
impedance of each of the respective antennas. The reactances and
the arrangement of reactive elements in the circuit are selected
such that when a broadband RF signal is applied at the input
terminal each of the two or more disjoint certain frequency ranges
are applied at the respective output terminals. The reactances and
the arrangement of reactive elements in the circuit are also
selected such that the impedance of the circuit at each output
terminal sufficiently matches the certain output terminal impedance
and that the power at each output terminal sufficiently matches the
certain power and insertion losses are minimized.
[0007] Another embodiment of the high-power multiplexer may be
described as comprising a first terminal, a first high pass filter,
and a first low pass filter. The first high pass filter has a first
plurality of inductive elements arranged in series between the
first terminal and a second terminal. The first high pass filter
also has a first plurality of capacitive elements connected in
parallel with the first plurality of inductive elements. Each
connection point between two inductive elements of the first
plurality of inductive elements is connected to a first end of a
respective capacitive element. Second ends of each of the first
plurality of capacitive elements are electrically connected. The
first low pass filter has a second plurality of capacitive elements
arranged in series between the first terminal and a third terminal.
The first low pass filter also has a second plurality of inductive
elements connected in parallel with the second plurality of
capacitive elements. Each connection point between two capacitive
elements of the second plurality of capacitive elements is
connected to a first end of a respective inductive element of the
second plurality of inductive elements. Second ends of each of the
second plurality of inductive elements are electrically
connected.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The accompanying drawings, which are incorporated in and
form a part of the specification, illustrate example embodiments
and, together with the description, serve to explain the principles
of the invention. Throughout the several views, like elements are
referenced using like references. The elements in the figures are
not drawn to scale and some dimensions are exaggerated for
clarity.
[0009] FIG. 1A is a representation of a four-channel
multiplexer.
[0010] FIG. 1B is a representation of a four-channel multiplexer
connected to a four-channel demultiplexer.
[0011] FIG. 2 is a graph of channel frequency versus power for four
different antennas.
[0012] FIGS. 3A-3H are circuit diagrams.
[0013] FIGS. 4A-4C are circuit diagrams.
[0014] FIG. 5 is a flow chart of a method for reducing cable runs
on a platform.
[0015] FIG. 6 is an expanded, perspective view of a capacitive
element.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0016] FIG. 1A is a simple illustration of a high-power multiplexer
100 for reducing the number of cables of communications systems
between a system's antennas and the rest of the system. A single
cable 101, instead of multiple cables (e.g. four cables), may be
coupled between communication electronics 103 and high-power
multiplexer 100. The single cable 101, may span at least a portion
D.sub.1 of the distance between the communication electronics 103
and the antennas 110, instead of multiple cables. Thus, if a single
cable 101 is used in conjunction with the high-power multiplexer
100 to replace four cables, the high-power multiplexer 100 would
allow for a weight savings of three cables spanning distance
D.sub.1 from the high-power multiplexer 100 to the communication
electronics 103. It may be advantageous (in terms of overall cable
weight savings) to position the high-power multiplexer 100 closer
to the antennas 110 than the communications electronics 103 in the
overall average distance between the antennas 110 and the
electronics 103. As used herein, the phrase "high-power" may be
defined as having a power-handling capability of greater than or
equal to three watts. For example one embodiment of the high-power
multiplexer 100 may have power-handling capabilities as follows:
1000 watts for high frequencies (3-30 MHz), 250 watts for very high
frequencies (30-300 MHz), and 100 watts for ultra-high frequencies
(300 MHz-3 GHz).
[0017] It should be appreciated that the high-power multiplexer 100
may have multiple terminals. For example, the high-power
multiplexer 100 is depicted in FIG. 1A as having four terminals,
one for each of the antennas 110. It is appreciated that the
multiple terminals may be input terminals if the signals from the
antennas 110 are intended to be input to the high-power multiplexer
100 for further relay to the communications electronics 103. It is
appreciated that the multiple terminals may be output terminals if
the signal(s) from the communications electronics 103 are to be
output to the antennas 110. In other words, the high-power
multiplexer 100 is bidirectional such that it may serve as a
multiplexer or a demultiplexer. The cables leading from the
high-power multiplexer 100 to the antennas 110 may have an average
length. The length of the cable 101 may be 1.25 times or more, 2
times or more, 3 times or more, 5 times or more than the average
length of the cables from the device to the antennas 110.
[0018] FIG. 1B illustrates block diagram of use case for high-power
multiplexer 100 for reducing the number of cable runs for a portion
D.sub.2 of the distance between antennas 110 and communications
electronics 103 for two high-power multiplexers 100 that can be
coupled to either side of the cable 101, one serving as a
multiplexer, the other serving as a demultiplexer. This
configuration may be used where the communication electronics 103
has multiple terminals. The communication electronics 103 may
require the multiple signals from/to the antennas 110 to be routed
into a respective terminal such as for multiple radios. The radios
may be tunable radios, and components of the high-power multiplexer
100 may be tunable. Each of the high-power multiplexers 100 shown
in FIG. 1B has the same components and configuration as the other
and are laid out in the mirror image of each other (i.e., one
high-power multiplexer 100 has one input and multiple outputs, the
other has multiple inputs and one output).
[0019] FIG. 2 illustrates a graph 200 of example signal frequency
ranges and signal power levels for antennas 110 that may be
accommodated by the high-power multiplexer 100. The high-power
multiplexer 100 can transform an input broadband signal input into
required signals for two or more antennas 110. The high-power
multiplexer 100 can transform signals from two or more antennas 110
into a single broadband signal required by communications
electronics 103 (or to be input into another high-power multiplexer
100 as seen in FIG. 1B). The broadband signal may be a
communication signal for processing by communications electronics,
including radios.
[0020] It can be appreciated that each antenna of the antennas 110
may have disjoint frequency ranges. For example, FIG. 2 illustrates
signal power and frequency characteristics for four different
antennas: A, B, C, and D. Antenna A has a frequency range of 2-9
MHz, at 1 kW, and a Voltage Standing Wave Ratio of 4:1 VSWR.
Antenna B has a frequency range of 30-88 MHz, at 250 W, 3.5:1 VSWR.
Antenna C has a frequency range of 115-162 MHz, at 250 W, 2:1 VSWR.
Antenna D has a frequency range of 220-400 MHz, at 100 W, 2:1
VSWR.
[0021] The following is a description of characteristics of another
example embodiment of the antennas 110 having eight separate
antennas. In this embodiment, the first antenna has a frequency
range of 7-30 MHz, at 1 kW, 4:1 VSWR. The second antenna in this
embodiment has a frequency ranges of 118-174 MHz, at 250 W, 2:1
VSWR. The third antenna in this embodiment has a frequency ranges
of 225-460 MHz, at 100 W, 2:1 VSWR. The fourth antenna in this
embodiment has a frequency range within 1-9 MHz. The fifth antenna
in this embodiment has a frequency range within 24-96 MHz. The
sixth antenna in this embodiment has a frequency range of 2.5 to 12
MHz. The seventh antenna in this embodiment has a frequency range
within 10-95 MHz. The eighth antenna in this embodiment has a
frequency range within 200-470 MHz. In this embodiment of the
antennas 110, the antennas 110 operate at a power level 0.15 to 5
kW. The communications electronics 130 may require signals at
scaled power compared to signals to/from the antennas 110. It is
appreciated that the antennas 110 may each operate at disjoint
frequency ranges, where disjoint means no two antennas have
overlapping required passbands. Two or more antennas 110 may have
at least partially overlapping frequency ranges.
[0022] It can be appreciated that the high-power multiplexer 100
may provide relatively good signal transmission with low loss in
the passband of frequencies required by each antenna of the
antennas 110. It is appreciated that the high-power multiplexer 100
may provide a low transmission in the frequencies outside of the
passband, Stated otherwise, the high-power multiplexer 100 may
provide a high out-of-band rejection to each antenna. It is
appreciated that the antennas 110 can each have an expected
impedance, signal frequency range, and signal power, and the
high-power multiplexer 100 can provide each antenna 110 with
signals of expected frequency, power, and at the required input
impedance. An expected high-power antenna power can be 100 to 3000
W.
[0023] Some embodiments of the high-power multiplexer 100 include
capacitive elements, have reactances that can be selected such that
impedance at the input terminal can substantially match the
impedance of at least one of the at least two output terminals.
Reactances of the elements of the high-power multiplexer 100 can be
selected such that an impedance at the output terminals can match
an impedance expected by antennas coupled to the output terminals.
An expected impedance can be 50 Ohms. The reactances and/or the
arrangement of the elements of the high-power multiplexer 100 can
be selected such that insertion losses and power losses in the
high-power multiplexer 100 can be minimized.
[0024] Although not shown in FIG. 2, the antennas 110 and/or
communications electronics 103 can require 1 dB or less insertion
loss (at the required frequency range), with at least 20 dB channel
isolation. The antennas 110 and/or communications electronics 103
can require less than 1 dB insertion loss (such as 0.5 dB), with at
least 35 dB channel isolation. The upper/lower channel isolation
may be 35 dB, 40 dB, 45 dB, 50 dB, 68 dB, 70 dB, 71 dB, 79 dB, 86
dB, or 90 dB.
[0025] FIGS. 3A-3H illustrate example embodiments of the high-power
multiplexer 100 that comprise a cochlear and manifold configuration
of circuit elements. A cochlear and manifold configuration for the
high-power multiplexer 100, may have a first terminal 301, and two
or more other terminals 305. The first terminal 301 may be a
terminal for input signal to the high-power multiplexer 100, where
the input is a broadband signal. The broadband signal may be
transferred to the high-power multiplexer 100 via single cable 101
(Not shown in FIGS. 3A-3H, please see FIGS. 1A-1B). The input at
first terminal 301 may be from communications electronics 103 such
as is shown in the depiction of the embodiment of the high-power
multiplexer 100 of FIG. 1A, where the two or more other terminals
305 are output terminals for providing communications (or other)
signals to antennas 110 (Not shown in FIGS. 3A-3H, please see FIGS.
1A-1B).
[0026] Alternatively, the first terminal 301 may be a terminal for
an output signal of the high-power multiplexer 100, where the
output is a broadband signal. The broadband signal may be
transferred from the high-power multiplexer 100 from output
terminal 301, via single cable 101, to communications device 103
(or another input of a communications device 103 as seen in FIG.
1B). In the case where terminal 301 is an output, the two or more
terminals 305 may be input to the high-power multiplexer 100. The
input terminals may be signals from antenna 110.
[0027] The embodiment of the high-power multiplexer 100 shown in
FIG. 3A has two bandpass filter blocks 310. The bandpass filter
block 310 may be a multi-order bandpass filter. The bandpass filter
block 310 may have a Chebychev topology, Bessel topology,
Butterworth topology, or other topologies as known in the art. The
bandpass filters 310 can have a passband frequency range. The
bandpass filter block 310 may have a frequency range. A frequency
may be outside of the passband and/or frequency range if that
frequency applied at a terminal of the bandpass filter block 310 is
attenuated with less than a -3 dB attenuation at the other
terminals of the bandpass filter block 310. The lower and higher
frequencies in the frequency range may be the frequencies with
approximately -0.3 dB, -0.5 dB, -1 dB, or -3 dB attenuation. The
lower and higher frequencies in the frequency range may be the
frequencies with the second -3 dB attenuation, for example, in a
Chebychev topology of the bandpass filter block 310. A frequency
may be within the passband and/or within the frequency range for
the bandpass filter block 310, if a signal that has that frequency
applied at an input terminal of the bandpass filter block 310,
appear at the other of two terminals of the bandpass filter block
310 with not less than -3 dB attenuation. The signal with a 0 dB
attenuation may be the fundamental, or resonance, or mid-band
frequency. The lower frequency in a given passband may be referred
to herein as a bottom end and the higher frequency in the given
passband may be referred to herein as a top end.
[0028] It is appreciated that the passband of the bandpass filter
and/or the frequency range of the filter block 310 may be
approximately equal to the desired frequency range of the antennas
110, and/or communication devices 103, which can be coupled to the
one or more terminals 305.
[0029] As shown in FIGS. 3A-3C, the high-power multiplexer 100 may
further have one or more inductive element 315, where each
inductive element 315 can be comprised of one or more inductors.
The inductive elements 315 may be designed to minimize loss from
the first terminal 301 of the device to the two or more filter
blocks 310. Inductance of the inductive elements may be selected to
match impedance in the high-power multiplexer 100 and/or to
minimize insertion losses in the device 110. The high-power
multiplexer 100 may be disposed on a printed circuit board (PCB),
and the inductance of the at least two inductive elements 315 can
be determined to minimize the loss across conductive traces of the
PCB from first terminal 301 to the filter blocks 310. The inductive
elements 315 may have filtering properties. The inductance of the
at least two inductive elements can be determined to match the
impedance across conductive traces of the PCB from the input
terminal to each bandpass filter block 310.
[0030] It can be appreciated that the number of inductive elements
315 may be equal to the number of filter blocks 310. In one example
embodiment, the inductive elements 315 can have an inductance of 3
nH, but it is to be understood that the inductive elements 315 are
not limited to that value.
[0031] Now referring to FIGS. 3A-3C, there can be one circuit block
335, one circuit block 340, and zero (FIG. 3A) or more (FIGS.
3B-3C) circuit blocks 330. The circuit block 335 can include the
aforementioned inductive element 315, in series with a bandpass
filter block 310, and terminal 305. Circuit block 330 can include
inductor 315, bandpass filter block 310, and terminal 305. Terminal
305 of circuit block 330 can be in series with bandpass filter
block 310 of that circuit block 330. Circuit block 335 can be
coupled to circuit block 330, at a node n1 (FIGS. 3B-3C) between
the bandpass filter block 310 of circuit block 330 and inductive
element 315 of circuit block 330.
[0032] The circuit block 340 can have an inductive element 315 in
series with terminal 301, and a bandpass filter block 310 in series
with the terminal 305 (and the inductive element 315). The series
combination of bandpass filter block 310 and terminal 305, can be
parallel to the series combination of inductive element 315
belonging to circuit block 340 and terminal 301. A node n2 of
circuit block 340 can be between bandpass filter block 310 of
circuit block 340, and inductive element 315 of the most
electrically proximal (adjacent) circuit block 330 or circuit block
340). In other words, node n2 of circuit block 340 is disposed at
the three-way junction of the bandpass filter block 310 of circuit
block 340, the inductive element 315 of circuit block 330, and the
inductive element 315 of circuit block 340. (See FIG. 3B). In other
words, the inductive element 315 of circuit block 330, can be
arranged between node n1 of circuit block 330, and the node n2 of
circuit block 340.
[0033] For designing an embodiment of the high-power multiplexer
100 with a cochlear manifold configuration for interfacing with two
or more antennas, zero or more circuit blocks 330 can be used. It
is appreciated that for interfacing two or more antennas, the
high-power multiplexer 100 can include a single terminal 301, a
circuit block 340, a circuit block 335, and two less than the
number of antennas, of circuit block 330. In total, there can be
the same number of terminals 305 as the number of antennas to be
interfaced with, with each respective terminal 305 belonging to
circuit block 340, circuit block 335, and each of the circuit
block(s) 330 (if included).
[0034] Moreover, if required in the design of a given embodiment of
the high-power multiplexer 100, the multiple circuit blocks 330 can
be arranged between circuit blocks 335 and circuit block 340, with
circuit block 335 coupled to node n1 of one of the circuit blocks
330. The inductive element 315 of that circuit blocks 330 can be
coupled to node n1 of another circuit block 330. Inductive element
315 of another (electrically proximal) of the multiple circuit
blocks 330 can be coupled to node n2 of circuit block 340. It can
be appreciated that for N terminals, N-2 blocks 330 can be
repeated. Circuit block 335 can include bandpass filter block 310
having the passband with the lowest top end. Circuit block 340 can
have bandpass filter block 310 having the passband with the highest
top end of the circuit blocks 310 of the high-power multiplexer
100. If required in the design of the high-power multiplexer 100,
the circuit block 335 may be coupled to the circuit block 330
having the passband with the lowest top end out of all of the
circuit blocks 330. Each of the circuit blocks 330 can be arranged
by decreasing higher frequency of the frequency range of each
bandpass filter block 310 belonging to that circuit block 330.
[0035] For example, FIG. 3A shows and embodiment of the high-power
multiplexer 100 for interfacing with two antennas (not shown in
FIG. 3A) via terminals 305. A single circuit block 330 can couple
to a single circuit block 340, at node n2 of circuit block 340. A
terminal 301 in series with inductive element 315 of circuit block
340, can be, for example, for interfacing with a single cable 101
(not shown in FIG. 3A).
[0036] FIG. 3B shows another example embodiment of the high-power
multiplexer 100 for interfacing with three antennas (not shown in
FIG. 3B) via respective terminals 305. The high-power multiplexer
100 can have one circuit block 330, having a terminal 305 in series
with bandpass filter block 310, and the bandpass filter block 310
coupled to inductive element 315 at node n1. A block 335 (as
described above), can couple to block 330 at node n1. A block 340
can be coupled between block 330 and the terminal 301 as described
above.
[0037] FIG. 3C shows another embodiment of the high-power
multiplexer 100 for interfacing with four antennas (not shown in
FIG. 3C) via four terminals 305. As shown, two of the circuit
blocks 330 can be repeated, with a circuit block 335 coupled to
node n1 of one of the circuit blocks 330. An inductive element of
that one of the circuit blocks 310 can be coupled to node n1 of
another of the two circuit blocks 310. The inductive element 315 of
that another of the two circuit blocks 310, can be coupled to node
n2 of the circuit block 340.
[0038] For clarity in designing different embodiments of the
high-power multiplexer 100 for interfacing between five or more
antennas (not shown in FIGs), ellipses are shown between the two
blocks 330 in FIG. 3C which shows the device for interfacing with
four antennas. It can be appreciated that embodiments of the
high-power multiplexer 100 for interfacing with five or more
antennas, can have three or more of circuit blocks 330, with the
inductive element 315 of each of the circuit blocks 330 (except for
one circuit block 330, which has inductive element 315 connected to
node n2 of its adjacent circuit block 340), connected to node n1 of
the adjacent circuit block 330.
[0039] The filter blocks 310 may be arranged by decreasing higher
frequency of the frequency range of each bandpass filter block 310.
The filter blocks 310 may be arranged by decreasing midband
frequency and/or fundamental frequency. The filter blocks may be
arranged by decreasing smaller frequency of the frequency range of
each bandpass filter block 310. The bandpass filter block 310 with
the highest frequency of the respective frequency range of the
bandpass filter block 310, and/or highest mid-band frequency and/or
highest fundamental frequency, and/or higher bottom end of the
respective frequency ranges of the filter blocks 310, may be
positioned proximal to the first terminal 301. That bandpass filter
block 310 may be electrically proximal to the first terminal 301.
Electrically proximal filter 310 can be taken to mean the least
impedance difference, or smallest potential difference, between the
first terminal 301 and all other filter blocks 310, but not
necessarily be the most physically proximate bandpass filter block
310 to the first terminal 301.
[0040] If the filter blocks 310 are arranged by decreasing
frequencies (see section above), each subsequent pair of filters
blocks 310 can be spaced apart by one of the inductive elements
315, and each bandpass filter block 310, together with a respective
circuit block (not shown in FIGs) for the respective other terminal
305 for that block 310, can be arranged in parallel, which can
include: i) Each other bandpass filter block 310 that has a lower
bandpass higher frequency (or lower midband frequency) than that
bandpass filter block 310; ii) Respective inductive elements 310 of
said each other filter blocks 310; and, ii) Respective terminals
305 of said each other filter blocks 310. For example, now
referring to FIG. 3B, a circuit block (not shown) that includes
bandpass filter block 310 and terminal 305 of circuit block 330, at
node n1 of block 330, is arranged in parallel with circuit block
335. Block 335 can include an inductive element 315, in series with
a bandpass filter block 310 that has a lower bandpass higher
frequency (or lower midband frequency) than the bandpass filter
block 310 of circuit block 330, and terminal 305.
[0041] Referring now to FIGS. 3D-3H, example filter blocks 310 are
shown according to several embodiments can be shown in greater
schematic detail. As shown, the filter blocks 310 can be bandpass
filters as described herein, and can include one or more inductive
elements and one or more capacitive elements. The higher cutoff
frequency of the bandpass filter (so the higher frequency of the
pass band) may be determined by any combination of inductive
elements in series with a terminal of the bandpass filter block
310, and/or capacitive elements in parallel with the terminal (or a
load applied at the terminal). The lower cutoff frequency of the
bandpass filter (so the lower frequency of the pass band) may be
determined by any combination of capacitive elements in series with
a terminal of the bandpass filter block 310, and/or inductive
elements in parallel with the terminal (or a load applied at the
terminal).
[0042] As shown in FIG. 3D, series stage 350 of the filter 310 can
be an inductive element in series with a capacitive element and
together in series with one of the two or more other terminals 305
of the device (see in FIGS. 3A-3C). This series stage 350 may be a
series resonant band-pass filter. A parallel stage 355 of the
bandpass filter block 310 can be an inductive element in parallel
with a capacitive element and together in parallel with one of the
two or more other terminals 305 of the device (see in FIGS. 3A-3C).
The parallel capacitive element in second stage 355 may be used to
shunt unwanted frequencies to ground.
[0043] It can be appreciated that any number of stages can be used
to make up the bandpass filter block 310, including any number of
series stages 350 and parallel stages 355. In some embodiments, no
two stages of the same type (series stage 350, parallel stages 355)
can be adjacent. There can be an odd number of bandpass stages, and
reactances of elements of the stages can be symmetric about a
middle bandpass stage in an ordered arrangement of stages. In other
embodiments, the middle bandpass stage can be arranged as a
parallel stage 355. In still other embodiments, the middle bandpass
stage can be arranges as a series stage 350. Further, the
reactances of the elements of the stages can be selected such that
the stages are ordered with higher resonant frequencies arranged
proximal to the middle stage.
[0044] FIG. 3E shows an example embodiment of the bandpass filter
block 310 having a multistage bandpass configuration, for coupling
to antenna with frequency range A of 2-9 MHz (Please see FIG.
2).
[0045] FIG. 3F shows an example embodiment of the bandpass filter
block 310 having a multistage bandpass configuration, for coupling
to antenna with frequency range B of 30-88 MHz (Please see FIG.
2).
[0046] FIG. 3G shows an example embodiment of the bandpass filter
block 310 having a multistage bandpass configuration, for coupling
to antenna with frequency range C of 115-162 MHz (Please see FIG.
2).
[0047] FIG. 3H shows an example embodiment of the bandpass filter
block 310 having a multistage bandpass configuration, for coupling
to antenna with frequency range of 220-400 MHz (Please see FIG. 2).
With respect to FIGS. 3E-3H, it should be appreciated that the
achievement of the capacitance values shown in FIGS. 3E-3H may be
achieved through the use of capacitive elements such as are
described in co-pending U.S. patent application Ser. No. 16/457,534
by Frederick Verd, entitled "High-power RF Capacitor", which
application is hereby incorporated by reference herein.
[0048] FIGS. 4A-4C depict a cascading diplexer configuration
embodiment for the high-power multiplexer 100. In this embodiment,
the high-power multiplexer 100 has a first terminal 301 and two or
more other terminals 305 (FIGS. 4B-4C). FIG. 4B shows four of the
two or more other terminals 305, thus the high-power multiplexer
100 shown in FIG. 4B can be for interfacing with four antennas 110
or communications electronics 103 (not shown in FIG. 4, but see
FIG. 1B). The first terminal 301 may be a terminal for receiving an
input signal to the high-power multiplexer 100, where the input is
a broadband signal. The broadband signal may be transferred to the
high-power multiplexer 100 via single cable 101. The input at first
terminal 301 may be from communications electronics 103 of FIG. 1A,
and the device is high-power multiplexer 100 of FIG. 1A, where the
two or more other terminals 305 are output terminals for providing
communications (or other) signals to antennas 110.
[0049] Alternatively, the first terminal 301 may be a terminal for
an output signal of the high-power multiplexer 100, where the
output is a broadband signal. The broadband signal may be
transferred from the high-power multiplexer 100 from output
terminal 301, via single cable 101, to communications device 103
(or another input of a device 103 as seen in FIG. 1B). In the case
terminal 301 is an output, the two or more terminals 305 may be
input to the high-power multiplexer 100.
[0050] The embodiment of the high-power multiplexer 100 shown in
FIGS. 4A-4C can include one or more diplexer 410 (411, 412, 460,
461, 462, 463 also shown) coupled to the first terminal 301. The
diplexer 410 includes a low pass filter 415 and a high pass filter
420. The low pass filter 415 and/or the high pass filter 420 may
have a multi-order filter topology, a Chebychev topology, Bessel
topology, Butterworth topology, or other RF filter topology known
in the art. A frequency may be outside of the passband of either
the low pass filter 415 or the high pass filter 420 if that
frequency applied at an input terminal of the diplexer 410 is
attenuated with less than a -3 dB attenuation at the other
terminals of the low pass filter 415 or high pass filter 420. The
cutoff frequency of the high pass filter and the low pass filter
may be the frequencies with -3 dB attenuation. The cutoff
frequencies may be the frequencies with the second -3 dB
attenuation, for example, in a Chebychev topology of either the
high pass filter 420 or the low pass filter 415. A frequency may be
in the passband and/or for the low pass filter 415 or the high pass
filter 420 if a signal that has that frequency applied at the input
to the diplexer 410, appears at the respective terminal of either
the high pass filter 420 or the low pass filter 415, with not less
than -3 dB attenuation.
[0051] To select the cutoff frequencies of the filters 415, 420 of
the diplexers 410, 411, 412, 460, 461, 462, 463 respective required
antenna frequency ranges, and the number of antennas can be known
(see also FIG. 2 for example). Cutoff frequencies for either of the
diplexer, can be approximately upper or lower frequencies of the
required antenna frequency ranges (or the passband of the
antennas). Antennas may be ordered by frequency ranges, including
by descending mid-frequency, or descending lower frequency, or
descending upper frequency of the respective frequency ranges.
Antennas may be ordered by ascending mid-frequency, or ascending
lower frequencies, or ascending upper frequency of the respective
frequency ranges.
[0052] If there is an even number of antennas (each with a
respective frequency range), for N antennas 110 in an ordered
arrangement of antennas 110, the first diplexer 410 may be a
mid-band diplexer. The low pass cutoff of the low pass filter 415
of the mid-band diplexer 410 may be approximately the higher
frequency of the N.sup.th//2 antenna (where II denotes the integer
floor of the division). The high pass cutoff of the high pass
filter 420 of the mid-band diplexer 410 may be approximately the
lower frequency of the N.sup.th//2+1 antenna. The number of
diplexers can be the number of bands (or antennas)-1.
[0053] If there is an odd number of antennas 110, the high pass
cutoff for the high pass filter 420 of the mid-band diplexer 410
can be the lower frequency of the N.sup.th//2 antenna in the
sequence of antennas and the low pass frequency of the low pass
filter 415 mid-band diplexer 410 can be the higher frequency of the
N.sup.th//2-1 antenna in the sequence of antennas. Alternatively,
the high pass cutoff frequency of the high pass filter 420 of the
mid-band diplexer can be the lower frequency of the N.sup.th//2+1
antenna while the low pass filter 415 cutoff frequency can be the
higher frequency of the N.sup.th//2 antenna.
[0054] A second diplexer 411, which can be a low band diplexer, can
be coupled to the output of the low pass filter 415 of the first
diplexer. A second diplexer 412, which can be a high band diplexer
412 can be coupled to the output of the high pass filter 420 of the
first diplexer 410. The number of diplexers can be the number of
bands (or antennas)-1.
[0055] FIG. 4A shows an embodiment of the high-power multiplexer
100 for reducing the number of cable runs to three or more antennas
(not shown in FIG. 4A), having a cascading diplexer configuration.
An input to each diplexer can be connected to each of an input to a
low pass filter 415 of the each diplexer, and an input to a high
pass filter 420 of the each diplexer. The outputs of each of the
low pass filter 415 and high pass filters 420 of each diplexer can
be unconnected.
[0056] For coupling the high-power multiplexer 100 to three or more
antennas, there can be a first diplexer 410, and one or more other
diplexers (diplexers 411, 412, 460, 461, 462, 463 shown, others
implied by ellipses). For the "cascading" effective arrangement of
the diplexers, each of the one or more other diplexers can be
coupled to either the low pass filter 415 output of the first
diplexer 410, or the high pass filter 420 output of the first
diplexer 410 (but not both). Moreover, each of the fourth diplexers
and counting, can be coupled to an output of either the second
diplexer 411, or third diplexer 412 (but not both). Each diplexer
other than the first diplexer, can be similarly cascaded, by being
connected to the output of one or more other diplexer, in the
cascade of diplexers. In other words, an input to each diplexer in
a group consisting of the diplexers other than the first diplexer,
can be coupled to at least one of i) an output of a high-pass
filter of another diplexer (other than that diplexer) or ii) an
output of a low-pass filter of another diplexer (other than that
diplexer). An input to each diplexer (other than the first
diplexer), can be coupled to at least one output of a high-pass
filter 420 of another diplexer (other than that diplexer), at least
one output of a low-pass filter 415 of another diplexer (other than
that diplexer), or at least one output of a combination of
high-pass filter 420 of another diplexer (other than that
diplexer), or low-pass filter 415 of another diplexer (other than
that diplexer).
[0057] For coupling the high-power multiplexer 100 to three
antennas, for example, and as shown in FIG. 4A, there can be a
first diplexer 410, and a second diplexer 411 coupled to a low pass
filter 415 output (or high pass filter output 420) of the first
diplexer 410. Output terminals (not shown in FIG. 4A) for coupling
to each of the three antennas, can be coupled to each of the low
pass filter 415 output and the high pass filter 420 outputs of the
second diplexer 415, and the high pass filter 420 (or low pass
filter 415) output of the first diplexer 410 that is uncoupled to
the second diplexer 411. A low pass filter (not shown in FIG. 4A
can be coupled between the terminal and the high pass filter 420
(or low pass filter 415) output of the first diplexer 410 that can
be uncoupled to the second diplexer 411.
[0058] As yet another example and as seen in FIG. 4A, for coupling
the high-power multiplexer 100 to five antennas, for example, there
can be a first diplexer 410, a second diplexer 411 coupled to a low
pass filter 415 output of the first diplexer 410, and a third
diplexer 412 coupled to a high pass filter 420 output of the first
diplexer 410. Further, a fourth diplexer 460 can be coupled to a
low pass filter 415 output of the second diplexer 411. Output
terminals (not shown in FIG. 4B) for coupling to each of the five
antennas, can be coupled to each of the low pass filter 415 output
and the high pass filter 420 outputs of the fourth diplexer 460,
and the high pass filter 420 output of the second diplexer 410 that
is uncoupled to the fourth diplexer 460. Moreover, output terminals
can be coupled to each of the low pass filter 415 and high pass
filter 420 outputs of the third diplexer 420. A low pass filter
(not shown in FIG. 4A) can be coupled between the terminal and the
high pass filter 420 output of the third diplexer 412, as
needed.
[0059] For coupling the high-power multiplexer 100 to six antennas,
for example, there can be a first diplexer 410, a second diplexer
411 coupled to a low pass filter 415 output of the first diplexer
410, and a third diplexer coupled to a high pass filter 420 output
of the first diplexer 410. A fourth diplexer 460 can be coupled to
a low pass filter 415 output of the second diplexer 411. A fifth
diplexer 461 can be coupled to a high pass filter 420 output of the
second diplexer 411. Output terminals (not shown in FIG. 4B) for
coupling to each of the antennas, can be coupled to each of the low
pass filter 415 output, and the high pass filter 420 outputs, of
each of the third 412, fourth 460, and fifth 461 diplexers. A low
pass filter (not shown in FIG. 4B) can be coupled between the
terminal and the high pass filter 420 output of the third diplexer
412, as needed.
[0060] For coupling the high-power multiplexer 100 to eight
antennas, for example, there can be a first diplexer 410, a second
diplexer 411 coupled to a low pass filter 415 output of the first
diplexer 410, and a third diplexer coupled to a high pass filter
420 output of the first diplexer 410. A fourth diplexer 460 can be
coupled to a low pass filter 415 output of the second diplexer 411.
A fifth diplexer 461 can be coupled to a high pass filter 420
output of the second diplexer 411. A sixth diplexer 462 can be
coupled to the low pass filter 415 output of the third diplexer
412. A seventh diplexer 463 can be coupled to the high pass filter
420 output of the third diplexer 412. Output terminals (not shown
in FIG. 4A) for coupling to each of the antennas, can be coupled to
each of the low pass filter 415 output, and the high pass filter
420 outputs, of each of the fourth 460, fifth 461, sixth 462, and
seventh 463 diplexers.
[0061] For clarity, for coupling the device to nine antennas (not
shown in FIGS. 4A-4C), an eighth diplexer (not shown) can be
coupled to an output of either of the fourth 460 through seventh
463 diplexer. Terminals (not shown) can be connected to the outputs
of the eighth diplexer, and the outputs of the fourth 460 through
seventh 463 diplexers unconnected to the eighth diplexer.
[0062] Now referring to FIG. 4B, as an example, four antennas 110
can be coupled to the high-power multiplexer 100, a first antenna
110 having a range of DC to 9 MHz, a second antenna 110 having an
operating range of 30-88 MHz, a third antenna 110, having an
operating range of 115-174 MHz, and a fourth antenna having an
operating range of 225-400 MHz. A first, mid-band diplexer 410 can
be coupled to the first terminal 301 for receiving broadband
signal. The first diplexer 410 can have a low pass filter 415 with
a cutoff of 88 MHz, and a high pass filter 420 with a cutoff
frequency of 118 MHz. A second diplexer 411, the low band diplexer,
can have be coupled to the first diplexer 410 low pass filter 415
output and have a second diplexer 411 low pass filter 415 cutoff of
20 MHz. The second diplexer 411, the low band diplexer, can further
have a second diplexer 411 high pass filter 420 cutoff of 30
MHz.
[0063] A third diplexer 412, which can be a high band diplexer, can
be coupled to the output of the first diplexer 401 high pass filter
420. The third diplexer 412 can have a third diplexer 412 high pass
filter 420 with a cutoff of 220 MHz, and a third diplexer 412 low
pass filter 415 with a cutoff of 174 MHz. One of the four terminals
305 for coupling to the first antenna operating at DC to 9 MHz can
be coupled to the output of the second diplexer 411 low pass filter
415. Another terminal 305 for coupling to the second antenna
operating at 30-88 MHz can be coupled to the output of the second
diplexer 411 high pass filter 420. Another terminal 305 for
coupling to the third antenna operating at 115-174 MHz can be
coupled to the output of the third diplexer 412 low pass filter 415
output. The fourth antenna having an operating range of 225-400 MHz
can be coupled to the output of the third diplexer 412 high pass
filter 420, via a lowpass filter (not shown), having a cutoff of
400 MHz.
[0064] Referring now to FIG. 4C, the electrical circuitry for the
three channel multiplexer is shown in greater detail. FIG. 4C shows
an example high-power multiplexer 100 for coupling to three
antennas (with frequency ranges DC to 88 MHz, 118 MHz to 174 MHz,
and 220 MHz and above) and having cascaded diplexers is shown. A
first terminal 301 can be for receiving a broadband signal. A first
diplexer 410 connected to the first terminal 301, can have a low
pass filter 415 with an 88 MHz cutoff, and a high pass filter 420
with an 118 MHz cutoff. A terminal 305 for coupling to an antenna
with a DC to 88 MHz operating range, can be connected to the output
of the low pass filter 415 of the first diplexer 410. A second
diplexer 411, is connected to the output of the high pass filter
420 of the first diplexer 410. The second diplexer can have a high
pass filter 420 with a 220 MHz cutoff frequency, and a low pass
filter 415 with a 174 MHz cutoff frequency. A second terminal 305
for coupling with the antenna having frequency ranges DC to 88 MHz
can be connected to the low pass filter 415 of the first diplexer
410. A third terminal 305 for coupling to the antenna operating at
118 MHz to 174 MHz, can be coupled to the output of the low pass
filter 415 of the second diplexer 411. A fourth terminal 305 for
coupling the high-power multiplexer 100 to an antenna operating
from 220 MHz can be coupled to the output of the second diplexer
411 high pass filter 420.
[0065] In some embodiments, the cascaded diplexer of FIGS. 4A-4C
may further require discrete low pass filters or high pass filters
instead of full diplexers 410, with no reciprocal high pass filter
420 or low pass filter 415 in the diplexer 410. For example if the
antennas operate at DC to some frequency, the terminal 305 that can
couple to that antenna may be connected to a low pass filter 415
having a cutoff frequency about that antenna frequency. Thus, the
device may be designed with no diplexer arrangement 410 having a
high pass filter 420 paired with that low pass filter 415. This can
be shown at least in FIG. 4C, at the second terminal 305 for
coupling with antenna having frequency ranges DC to 88 MHz, can be
connected to the low pass filter 415 of the first diplexer 410 of
FIG. 4C.
[0066] In some embodiments, the high-power multiplexer 100 may have
a combination of cascaded diplexer arrangement, and cochlear
manifold arrangement as seen in FIGS. 3A-3D. For example, circuit
blocks 335, 330, and/or 340 as seen in FIGS. 3A-3C may be coupled
to the output of either a high pass filter 420 or low pass filter
415 of one or more diplexers 410.
[0067] Some embodiments of the high-power multiplexer 100 feature
cooling means. Cooling means may include nonconductive cooling,
liquid cooling, phase change materials, nonconductive cooling
between the capacitive element and conductive cooling. Cooling fins
may be attached to the capacitive elements of the high-power
multiplexer 100. Where the capacitive elements are embedded in a
PCB, cooling fins can be perpendicular to a plane of the PCB.
Effectiveness of cooling means can be expressed in dB, or expressed
in temperature (at certain frequency and power).
[0068] In embodiments where the device is embedded in a PCB,
capacitive elements may be high-power RF capacitors embedded into
the layers of the PCB. For example, the capacitors of FIG. 4C
and/or FIGS. 3E-3H can be such PCB embedded capacitors.
[0069] In some embodiments of the high-power multiplexer 100,
grounding straps may be added to ground of terminals 305, to create
a uniform ground plane and improve channel isolation across the
passband. In some embodiments, capacitors can be added to shunt
inductors to reduce their inter-turn capacitance response at
certain frequencies.
[0070] FIG. 5 shows a method 500 for reducing a number, or quantity
of cable runs to antennas. The method 500 includes the step 510 of
providing an input terminal. The input terminal can receive a
broadband RF signal from a single input cable. The RF signal can be
from DC to 1000 MHz. The method further includes the step 520 of
providing at least two output terminals. Each output terminal can
be configured to transmit output signals to a respective antenna at
an expected; i) impedance, ii) signal frequency range and iii)
signal power for the output signals. The antenna can exhibit a load
at the terminal.
[0071] The method 500 further includes the step 530 of providing a
circuit of reactive elements coupled between the input terminal and
the at least two output terminals. The circuit can separate the
broadband signal into two or more expected (by the antennas)
frequency ranges. The frequency ranges can be disjoint. In other
words, the channels to the antennas can have at least 20 dB channel
isolation. In other words, the antennas can have non-overlapping
ranges. The circuit can further match the impedance of the circuit
to certain impedance expected by the antennas. The reactances and
the arrangement of reactive elements in the circuit can be selected
such that when a broadband RF signal is applied at the input
terminal, each of the two or more disjoint frequencies are applied
at the respective output terminals while i) the impedance of the
circuit at each output terminal sufficiently matches the certain
impedance at the output terminal, ii) the power at each output
terminal sufficiently matches a certain power, and ii) insertion
losses are minimized throughout the device. At least a portion of
the circuit can have at least one of a cochlear manifold bandpass
circuit arrangement, or a cascaded diplexer arrangement (or both).
In other words, the circuit can have either a cochlear manifold
bandpass circuit arrangement, or a cascaded diplexer arrangement,
or both.
[0072] The method 500 can further include the step 540 of providing
a single input cable at the input terminal. The method 500 can
further include the step 550 of providing multiple output cables
between the output terminals and the two or more antennas. The
input cable can have a length larger than the average length of the
output cables. The method 500 can further include the step 560 of
providing a cooling element proximal to reactive elements. The
cooling element can be configured as a cooling means sufficient to
minimize losses in the device. The cooling means can include
conductive fins coupled to the capacitive elements.
[0073] The cascaded diplexer approach, as seen at least in FIGS.
4A-4C may be advantageous over the cochlear and manifold approach
shown in FIGS. 3A-3H, in applications where reactive elements may
be selected with lower current, voltage, and/or power ratings. The
cochlear manifold approach may be advantageous in other situations
where a high insertion loss at frequency can be required by one of
the antennas, but that is distant from the midband frequency.
[0074] FIG. 6 is an illustration of an embodiment of a capacitive
element 800 that is integrated into a printed circuit board
dielectric substrate 802. In this embodiment, the capacitive
element 800 comprises a first conductive layer 804 deposited on a
first side 806 of the dielectric substrate 802 and a second
conductive layer 808 deposited on an opposite side 810 of the
dielectric substrate 802. This arrangement of conductive layers
provides a broadside coupling capacitance effect between the first
conductive layer 804 and the second conductive layer 808. In this
embodiment of the capacitive element 800, the first conductive
layer 804 and the second conductive layer 808 have a double-sided
comb shape. Also shown in FIG. 6 is an optional cooling fin 812
that may be attached to the capacitive element 800 so as to enable
heat transfer away from the capacitive element 800.
[0075] The foregoing description of various embodiments have been
presented for purposes of illustration and description. It is not
intended to be exhaustive or to limit the invention to the precise
forms disclosed, and many modifications and variations are possible
in light of the above teachings. The example embodiments, as
described above, were chosen and described in order to best explain
the principles of the invention and its practical application to
thereby enable others skilled in the art to best utilize the
invention in various embodiments and with various modifications as
are suited to the particular use contemplated. It is intended that
the scope of the invention be defined by the claims appended
hereto. Reference in the specification to "one embodiment" or to
"an embodiment" means that a particular element, feature,
structure, or characteristic described in connection with the
embodiments is included in at least one embodiment. The appearances
of the phrases "in one embodiment", "in some embodiments", and "in
other embodiments" in various places in the specification are not
necessarily all referring to the same embodiment or the same set of
embodiments.
[0076] Some embodiments may be described using the term "element".
An element may be comprised of multiple discreet elements that
co-operate or interact with each other to have substantially the
properties of the element. For example,
capacitive/inductive/resistive elements may be comprised of
multiple capacitive/inductive/resistive elements in series and/or
in parallel.
[0077] Some embodiments may be described using the expression
"coupled" and "connected" along with their derivatives. For
example, some embodiments may be described using the term "coupled"
to indicate that two or more elements are in direct physical or
electrical contact. The term "coupled," however, may also mean that
two or more elements are not in direct contact with each other, but
yet still co-operate or interact with each other. The embodiments
are not limited in this context.
[0078] As used herein, the terms "comprises," "comprising,"
"includes," "including," "has," "having" or any other variation
thereof, are intended to cover a non-exclusive inclusion. For
example, a process, method, article, or apparatus that comprises a
list of elements is not necessarily limited to only those elements
but may include other elements not expressly listed or inherent to
such process, method, article, or apparatus. Further, unless
expressly stated to the contrary, "or" refers to an inclusive or
and not to an exclusive or.
[0079] Additionally, use of the "a" or "an" are employed to
describe elements and components of the embodiments herein. This is
done merely for convenience and to give a general sense of the
invention. This detailed description should be read to include one
or at least one and the singular also includes the plural unless it
is obviously meant otherwise.
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