Method and apparatus for carrying signals having different frequencies in a space-deployed antenna system

Information

  • Patent Grant
  • 6268827
  • Patent Number
    6,268,827
  • Date Filed
    Friday, October 29, 1999
    24 years ago
  • Date Issued
    Tuesday, July 31, 2001
    23 years ago
Abstract
The present invention provides a method and apparatus for carrying signals having different frequencies in a space-deployed antenna system. When the antenna system is in a first mode, DC power, command information and RF signals (1) are multiplexed via a multiplexer, (2) propagate along a RF transmission line and (3) are appropriately demultiplexed by a demultiplexer associated with each T/R module. Similarly, when the antenna system is in a second mode, telemetry data and RF signals (1) are multiplexed via a multiplexer, (2) propagate along the RF transmission line and (3) are appropriately demultiplexed by a demultiplexer at a driver stage. By using the RF transmission lines associated with each T/R module to deliver (1) DC power, (2) command data and (3) RF signals in the first mode and to deliver (1) telemetry data and (2) RF signals in the second mode, the DC power and command/telemetry wire harnesses (and their respective conductors) may be eliminated. Thus, the overall weight of the antenna system may be reduced. Furthermore, deployment risks may be reduced. Finally, the overall cost of the antenna system may be reduced.
Description




FIELD OF THE INVENTION




The present invention relates to antenna systems and, more particularly, to antenna systems which are deployed in space.




BACKGROUND OF THE INVENTION




A communications satellite is an artificial satellite placed into orbit around earth to, among other things, facilitate communications on earth. Communications satellites normally include antenna systems, which typically receive information from and transmit information to various locations on earth.




Phased-array antenna systems, which are well-known, are one type of antenna system that has been used with communications satellites. A phased-array antenna system is comprised of a plurality of antenna elements which are suitably spaced relative to one another. The antenna system generates a radiation pattern having a shape and direction that is determined by the combination of the relative phases and amplitudes of the signals applied to the antenna elements. By varying the relative phases of the signals applied to the antenna elements, the antenna's direction of radiation may be steered.




Conventional phased-array antenna systems typically include a driver stage, a plurality of transmit/receive modules (“T/R modules”) and an RF feed network comprised of RF transmission lines. In addition, such antenna systems include a DC power wire harness having a plurality of DC power signal conductors and a digital command/telemetry signal wire harness having a plurality of command/telemetry signal conductors.




Thus, typically, in conventional phased-array antenna systems, each T/R module is electrically connected to the driver stage via (


1


) an RF transmission line, (


2


) a DC power signal conductor from the DC power wire harness and (


3


) a command/telemetry signal conductor from the digital command/telemetry signal wire harness. Both the DC power signal conductors and the command/telemetry signal conductors are typically several meters (or more) in length and require shielding, sheathing, connectors and connector back shells. Furthermore, both the DC power wire harness and the digital command/telemetry signal wire harness require mounting hardware. Thus, when a phased-array antenna system includes hundreds or more TIR modules, the complexity and weight of the system increases dramatically due to the presence of the DC power wire harness, digital command/telemetry signal wire harness and their respective conductors.




When communications satellites are deployed into space, costs associated with delivering spacecraft payloads into the earth's orbit are based on the payload's weight. Thus, there is a need to reduce the weight of antenna systems associated with communications satellites. In addition, because antenna deployment is one of the highest risk components of a space-based satellite mission, there is a need to reduce antenna deployment risks. Finally, there is a need to reduce antenna costs, including costs related to procurement, testing and installation.




SUMMARY OF THE INVENTION




The present invention is designed to overcome the aforementioned problems and meet the aforementioned, and other, needs.




It is an object of the present invention to reduce the weight of antenna systems associated with communications satellites.




It is another object of the invention to reduce antenna deployment risks.




It is yet another object of the invention to reduce antenna costs, including costs related to procurement, testing and installation.




In accordance with the objects of the invention, the present invention advantageously reduces the number of electrical connections made to each T/R module. More specifically, the present invention eliminates both the DC power wire harness and the digital command/telemetry wire harness (and their respective conductors), while still providing their associated signals from the driver stage to each T/R module. Even more specifically, when the antenna is in a first mode, DC power, command information and RF signals (


1


) are multiplexed via a multiplexer, (


2


) propagate along the RF transmission line and (


3


) are appropriately demultiplexed by a demultiplexer associated with each T/R module. Similarly, when the antenna is in a second mode, telemetry or operations-related data (including, e.g., status information) and RF signals (


1


) are multiplexed via a multiplexer, (


2


) propagate along the RF transmission line and (


3


) are appropriately demultiplexed by a demultiplexer at the driver stage.




By using the RF transmission lines associated with each T/R module to deliver (


1


) DC power, (


2


) command data and (


3


) RF signals in a first mode and to deliver (


1


) telemetry data and (


2


) RF signals in a second mode, the DC power and command/telemetry wire harnesses (and their respective conductors) may be eliminated. Thus, the overall weight of the antenna system may be reduced. Furthermore, deployment risks may be reduced since, in conventional systems, both the DC power wire harness and command/telemetry wire harness (and their respective conductors) may inhibit deployment mechanisms. Finally, the overall cost of the antenna system may be reduced since the components required to implement the multiplexer/demultiplexer circuits can be realized in inexpensive, silicon integrated circuits (or alternatively in discrete form) placed in each T/R module and in the driver stage. In contrast, there is relatively greater expense in procuring, testing and installing conventional wire harnesses and connecting them from the driver stage to each T/R module via DC power signal conductors and command/telemetry signal conductors.




Other objects, features and advantages of the invention will be apparent from the following specification taken in conjunction with the following drawings.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a simplified block diagram of an embodiment of the present invention, wherein command data, DC power and RF signals are being provided from the driver stage to the T/R modules without a DC power wire harness nor a command/telemetry wire harness (or their respective conductors);





FIG. 2

is a circuit diagram of the multiplexer shown in

FIG. 1

for an embodiment of the present invention;





FIG. 3

is a circuit diagram of the demultiplexer shown in

FIG. 1

for an embodiment of the present invention;





FIG. 4

is a block diagram of an embodiment of the present invention generally showing two modes in which the antenna system may operate;





FIG. 5

is a frequency plot showing the relative frequencies of the DC power signal, command signal, telemetry signal and RF signal for an embodiment of the present invention in a half-duplex configuration; and,





FIG. 6

is a frequency plot showing the relative frequencies of the DC power signal, command signal, telemetry signal and RF signal for an embodiment of the present invention in a full-duplex configuration.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT




While this invention is susceptible of embodiments in many different forms, there are shown in the drawings and will herein be described in detail, preferred embodiments of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the broad aspects of the invention to the embodiments illustrated.





FIG. 1

is a simplified block diagram of an embodiment of the phased-array antenna system


100


of the present invention, wherein control or command signals, DC power and RF signals, carrying data or other information, are to be provided from a driver stage


102


to each T/R module


104


. The antenna system


100


includes a driver stage


102


, T/R modules


104


, antenna elements


105


and an RF feed network


106


. The RF feed network


106


includes RF transmission lines


108


. Each of these lines


108


includes a single, preferably, center conductor that is used to carry all of the control/command, DC power and RF signals between the driver stage


102


and the T/R modules


104


. As will be understood by those skilled in the art, the antenna system


100


shown in

FIG. 1

is an active array, in that it includes separate T/R modules


104


for each antenna element


105


.




In contrast to typical phased-array antenna systems, the antenna system


100


shown in

FIG. 1

does not include a DC power wire harness or a digital command/telemetry signal wire harness (or their respective conductors). Instead, the phased-array antenna system


100


includes a multiplexer


110


(to be explained in further detail in connection with

FIG. 2

) preferably located proximate (or “within”) the driver stage


102


and a plurality of demultiplexers


112


(to be explained in further detail in connection with

FIG. 3

) preferably located proximate (or “within”) each T/R module


104


.




When the antenna


100


is in transmit mode, the multiplexer


110


combines command signal


114


, DC power signal


116


and RF signal


118


and transmits the combination of such signals across the RF feed network


106


via the RF transmission lines


108


. The combined signal is received at each T/R module


104


and is demultiplexed via the demultiplexer


112


associated with each T/R module


104


to obtain command signal


120


, DC power signal


122


and RF signal


124


at each T/R module


104


. Accordingly, the DC power wire harness and the digital command/telemetry signal wire harness (and their respective conductors), which are found in typical phased-array antenna systems, may be eliminated. As will be understood by those skilled in the art, a similar scheme may be used when telemetry signals and RF signals are to be transmitted from one or more T/R modules


104


to the driver stage


102


(as will be discussed in connection with FIG.


4


).





FIG. 2

is a circuit diagram of the multiplexer


110


of the antenna system


100


shown in FIG.


1


. The preferred values of the components of the circuit


200


of

FIG. 2

are indicated thereon; however, as will be understood by those skilled in the art, such values may be varied and equivalent components may be substituted therefor.




As mentioned above, the purpose of the multiplexer


110


(and, hence, the circuit


200


) is to combine command signal


114


, DC power signal


116


and RF transmission signal


118


. The combined signal is to be provided to pin


202


(Combined Sig. Out) shown in FIG.


2


. In an effort to simplify the discussion of the circuit


200


, it will generally be discussed in sections.




Command Section




The command section is indicated by the components surrounded by the dashed lines identified by reference numeral


220


. The ultimate goal of the command section


220


is to provide an amplified, modulated control or command signal out of amplifier U


4


.




The combination of transistor Q


1


, resistor R


10


, diode D


3


, crystal oscillator Y


2


, capacitor C


23


, capacitor C


24


and resistor R


11


forms a Collpitts oscillator which oscillates at the crystal frequency of 10.7 MHz (although many other values are possible). A modulator which includes the aforementioned oscillator and an on-off keying circuit (comprised of resistor R


16


, resistor R


15


, capacitor C


5


and transistor Q


3


) is provided. Because the oscillator takes a relatively long period to start up (approximately 1-2 milliseconds), the above-mentioned on-off keying circuit is provided, which improves the modulator's turn-on and turn-off times. Those skilled in the art will understand that other modulation formats may be substituted for the on-off keying (OOK) modulation described above.




Command data (i.e., the modulating signal), in the form of digital TTL level data, is provided to JP


4


via a microprocessor (not shown) or other conventional means. The command data is the modulating signal that is used to provide command signals which are supplied to T/R modules


104


. Thus, when the command signal is a “digital zero,” the collector of transistor Q


3


does not conduct to ground and allows the oscillator's signal to be provided to amplifier U


4


. Similarly, when the command signal is a “digital one,” the collector of transistor Q


3


grounds the oscillator's output to prevent the oscillator's signal from being provided to the amplifier U


4


. Accordingly, the command data signal is used as the modulating signal for the oscillator.




In case the oscillator is to be turned off (for example, to save power), rather than its output merely being shorted to ground, an oscillator enable/disable circuit is provided. Specifically, the oscillator enable/disable circuit includes transistor Q


2


, resistor R


13


, JP


2


and JP


1


.




By way of the oscillator and the on-off keying circuit (which is controlled via the command data signal), modulated control data is provided to amplifier U


4


. The main function of the amplifier is to amplify the modulated control data to improve signal to noise performance and ultimately generate an amplified, modulated command signal at its output.




DC Power Diplexer Section




The DC power diplexer section


230


, which is a combination of resistor R


17


and inductor L


4


, operates as a signal combiner. Thus, the DC power diplexer section is used to couple DC power from JP


3


with the amplified modulation signal.




RF Signal Combiner Section




The RF signal combiner section


240


includes capacitor C


6


, which operates as a DC blocker. (Alternative embodiments may include more elements in a πor T configuration, for example.) Thus, the RF signal from RF In is coupled to the amplified modulation signal and the DC power signal. Accordingly, the combination of all three signals are then provided at pin


202


(Combined Sig. Out).





FIG. 3

is a circuit diagram of the demultiplexer


112


of the antenna system


100


shown in FIG.


1


. The preferred values of the components of the circuit


300


of

FIG. 3

are indicated thereon; however, as will be understood by those skilled in the art, such values may be varied and equivalent components may be substituted therefor.




As mentioned above, the purpose of the demultiplexer


112


(and, hence, the circuit


300


) is to receive (via the RF feed network


106


) the combined signal output from the multiplexer


110


and to separate the command signal


120


, DC power signal


122


and RF signal


124


from the combined signal. With reference to

FIG. 3

, the combined signal is received at pin


302


(Combined Sig. In). In an effort to simply the discussion of the circuit


300


, it will generally be discussed in sections.




RF Signal Section




The RF signal section


310


is used to separate the RF signal from the combined signal in. Capacitor C


3


operates as a DC blocker so that the DC power signal can only be conducted through inductor L


3


. Similarly, inductor L


3


blocks the RF signal from the DC power diplexer section


320


and command signal section


330


. This serves to minimize parasitic loading of the RF signal at pin


302


. Accordingly, inductor L


3


permits the amplified modulated signal (having a frequency of about 10.7 MHz) and the DC signal to pass.




DC Power Diplexer Section




The DC power diplexer section


320


is used to separate the DC power signal from the amplified modulated signal. The DC power diplexer section includes the combination of inductor L


2


and resistor R


4


. Furthermore, capacitor C


7


and capacitor C


8


are used to remove residual AC components from the DC power signal.




Command Signal Section




The command signal section


330


is used to recover the command signal. The signal remaining after the RF and DC power signals have been split off is provided to ceramic filter Y


1


to obtain an adequate signal-to-noise ratio. An envelope detector, formed by the combination of resistor R


1


, inductor L


1


, diode D


1


and capacitor C


1


, is used to detect the envelope of the modulated signal in order to recreate the digital data signal. Further, R


2


and C


2


form a low-pass filter which is used to remove residual high-frequency components from the envelope. Finally, the remaining signal is provided to an adaptive comparator circuit formed by the combination of diode D


2


, capacitor C


9


, resistor R


6


and resistor R


9


. Diode D


2


and capacitor C


9


are charged up to the peak of the envelope, while resistor R


2


and resistor R


9


are set to produce an output on pin


5


which is ⅔ of the peak, which operates as a reference for the comparator U


1


A. The other input to the comparator U


1


A is the detected signal on pin


4


. Thus, the detected signal on pin


4


is compared to an adaptive reference. Accordingly, even when signal levels are low, an accurate determination may be made for detection of a peak. The output of the comparator, on pin


4


, is the command signal. Thus, the RF signal, DC power signal and the command signal are all separated as identified by reference numerals


340


,


350


and


360


, respectively.





FIG. 4

is a detailed block diagram of another embodiment, identified by reference numeral


400


, of the antenna system of the present invention. While

FIG. 1

showed how command, DC power and RF signals could be combined and transmitted from the driver stage


102


to the T/R modules


104


(and then be separated),

FIG. 4

shows (in addition to what is shown in

FIG. 1

) how telemetry and RF signals can be combined and transmitted from the T/R modules


404


to the driver stage


402


.




Thus, in a first mode, the antenna system


400


operates to combine (


1


) command, (


2


) DC power and (


3


) RF signals into a combined signal from the driver stage


402


to the T/R modules


404


, which combined signal is then separated into command, DC power and RF signals by the T/R modules


404


. Similarly, in a second mode, the antenna system


400


operates to combine (


1


) telemetry and (


2


) RF signals into a combined signal from a T/R module


404


, which combined signal is then separated into telemetry and RF signals at the driver stage


402


. As will be understood in the art, in order for both modes to be operable, both a multiplexer and demultiplexer are provided at each T/R module


404


and at the driver stage


402


. For convenience, however, (and to more clearly describe the invention) the multiplexer/ demultiplexer combination for the driver stage


402


is depicted as diplexer


410


. Likewise, the multiplexer/demultiplexer combination for each T/R module


404


is depicted as diplexer


412


.




As will also be understood by those skilled in the art, neither the multiplexer at each T/R module


404


nor the demultiplexer at the driver stage


402


includes a DC power diplexer (refer to FIGS.


2


and


3


), since the DC power signal need only supplied from the driver stage


402


to each T/R module


404


. Accordingly, DC power is supplied to all of the active elements via its transmission from the driver stage


402


to each T/R module


404


in a manner that will be understood by those skilled in the art.




Referring again to

FIG. 4

, certain components (shown in block diagram form) will now be described to show how the antenna system


400


operates in both modes. Specifically, driver stage


402


includes a command generator


424


, a telemetry receiver


426


, a control line


428


, a switch


430


, a command signal conductor


432


, a telemetry signal conductor


434


, an RF signal conductor


436


, a combined command/telemetry conductor


438


, a DC power conductor


440


and the aforementioned diplexer


410


.




When command, DC power and RF signals are to be delivered to the T/R modules


404


, the command generator


424


generates a control signal on control line


428


which causes switch


430


(which, in a preferred embodiment, is in a default position that electrically connects the telemetry receiver


426


to the combined command/telemetry conductor


438


via telemetry signal conductor


434


) to connect the command generator


424


to the combined command/telemetry conductor


438


. Thus, the command signal is provided to the diplexer


410


, where it is combined with the DC power and RF signals. The combined signal is then delivered across the RF feed network


450


via RF transmission lines


452


to all of the T/R modules


404


.




The T/R modules


404


include the aforementioned diplexer


412


, a T/R module select decoder


454


, a command receiver


456


, a telemetry generator


458


, a first control line


460


, a second control line


462


, a switch


464


, a command signal conductor


466


, a telemetry signal conductor


468


, an RF signal conductor


470


, a combined command/telemetry conductor


472


and a DC power conductor


474


. The demultiplexer


412


receives the combined signal and separates it into an RF signal, a command/telemetry signal and a DC power signal. The command signal is coupled to T/R module select decoder


454


via the combined command/telemetry conductor


472


and T/R module select decoder conductor


476


. The T/R module select decoder


454


determines whether the command data included in the command signal is intended for a particular T/R module


404


, since each T/R module


404


includes a unique electronic serial number or the like. More specifically, the T/R module select decoder


454


reads header information contained within the command signal (which includes, for example, an electronic serial number of a T/R module


404


) to determine whether it is the intended recipient of the command data being broadcast via the RF feed network


450


by comparing the header information to its electronic serial number. As will be understood by those skilled in the art, the specific protocol may also include a method of delivering global commands or commands to a group of T/R modules.




If the T/R module select decoder


454


determines that the command data is intended for its particular T/R module


404


, the T/R module select decoder


454


generates a control signal on first control line


460


, which causes switch


464


to couple command receiver


456


with combined command/telemetry conductor


472


via command signal conductor


466


. The command receiver


456


receives the command data, interprets it and performs a function in response thereto (such as varying the phase of the RF signal delivered to antenna element


205


, in order to steer the beam of the antenna


400


), as will be understood by those skilled in the art.




One of the functions that may be performed, based upon command data being provided to the command receiver


456


, is that telemetry information may be generated and provided from a particular T/R module


404


to the driver stage


402


. Such telemetry information may include, for example, the sensed temperature at a particular T/R module, internal voltages or currents, or many other operations-related (or non-operations related) parameters.




Thus, when a particular T/R module


404


is to be queried for specific telemetry information, command data is provided to such T/R module


404


as set forth above (wherein the command data specifies the particular telemetry information that is to be provided from the T/R module


404


to the driver stage


402


). In response, the telemetry generator


458


generates a first control signal on second control line


462


which is received by T/R module select decoder


454


. A second control signal is generated on first control line


460


, which causes the switch


464


to couple the telemetry generator conductor


468


to the combined command/telemetry conductor


472


so that telemetry data may be forwarded to diplexer


412


and be combined with RF signal. The combined received signal is then fed to driver stage


402


via RF feed network


450


.




The combined signal is received by the diplexer


410


which separates the combined signal into a telemetry signal and an RF signal. The telemetry signal is coupled to the telemetry receiver


426


via combined command/telemetry conductor


438


, switch


430


and telemetry receiver conductor


434


. To identify the particular T/R module


404


from which the telemetry information is being provided, the telemetry signal includes a header associated with the T/R module


404


(e.g., its electronic serial number or the like).





FIG. 5

is a frequency plot showing the relative frequencies of the DC power signal, command/telemetry signal and RF signal for the antenna system of the present invention in a half-duplex configuration. As will be understood by those skilled in the art, a half duplex configuration permits either command data or telemetry data (but not both at the same time) to be transmitted between the driver stage


402


and T/R modules


404


(e.g., a walkie-talkie). Accordingly, in the half duplex configuration, the command data and telemetry data are intended to be modulated at the same frequency. As shown in

FIG. 5

, the RF signal has a relatively high frequency defined by high-pass filter HPF, the DC signal has a relatively low frequency defined by low-pass filter LPF and the command/telemetry signals have a carrier frequency which is in an intermediate frequency range defined by bandpass filter BPF.





FIG. 6

is a frequency plot showing the relative frequencies of the DC power signal, command signal, telemetry signal and RF signal for the antenna system of the present invention in a full-duplex configuration. As will be understood by those skilled in the art, a full-duplex configuration permits command data and telemetry data to be transmitted between the driver stage


402


and the T/R modules


404


at the same time (e.g., a conventional wireline telephone). Accordingly, in the full-duplex configuration, the command data and telemetry data are intended to be modulated at different carrier frequencies. As shown in

FIG. 6

, the RF signal has a relatively high frequency defined by high-pass filter HPF, the DC signal has a relatively low frequency defined by low-pass filter LPF, the command signal has a first intermediate frequency defined by first bandpass filter BPF


1


and the telemetry signal has a second intermediate frequency defined by second bandpass filter BPF


2


.




As will be understood by those skilled in the art, instead of using a single driver stage as shown in the drawings, multiple driver stages may be provided. Furthermore, as will also be understood by those skilled in the art, elimination of solely the DC power wire harness would be beneficial since the DC power wire harness (and its associated conductors) are generally quite heavy and costly in order to minimize power losses. Accordingly, the principles of the present invention may be used to eliminate solely the DC power wire harness, instead of both, wire harnesses. Finally, it should be noted that the advantages of the present invention may be useful for phased-array antenna systems that are not deployed in space and; therefore, scope of the present invention should not be limited to the particular embodiments described herein.




It will be understood that the invention may be embodied in other specific forms without departing from the spirit or central characteristics thereof. For example, instead of providing power to the T/R modules via a DC signal, a low frequency AC signal (e.g., between 0-1000 Hz) may be used. Furthermore, it should be understood that telemetry information may be provided from the driver stage to one or more T/R modules. Even further, telemetry information may be generated automatically (after some predetermined time interval), instead of in response to a command signal from the driver stage. Finally, switch


464


, command receiver


456


, decoder


454


, telemetry generator


458


and line


466


could all exist in a single microcontroller, since they are simply functional entities and may be embodied in a variety of ways.




The present examples and embodiments, therefore, are to be considered in all respects as illustrative and not restrictive, and the invention is not intended to be limited to the details given herein.



Claims
  • 1. A method for carrying a number of different signals in an antenna system having a number of components including antenna elements, comprising:providing each of a power signal, a data signal and a command signal; carrying each of said power signal, said data signal and said command signal using a common conductor, wherein said command signal is addressed to a selected one of said antenna elements of said antenna system; separating each of said power signal, said data signal and said command signal; applying at least said power signal to a plurality of the components of the antenna system; and receiving said command signal by at least a one of said components associated with said selected one of said antenna elements and applying said command signal to said selected one of said antenna elements of said antenna system.
  • 2. A method, as claimed in claim 1, wherein:said command signal includes a modulated command signal having a frequency different from frequencies of each of said power signal and said data signal.
  • 3. A method, as claimed in claim 1, wherein:said providing step includes preventing substantially using filter circuitry said command signal from passing along a power conducting line carrying said power signal.
  • 4. A method, as claimed in claim 3, wherein:said providing step includes preventing substantially said command signal and said power signal from being conducted along a data conducting line that carries said data signal.
  • 5. A method, as claimed in claim 1, wherein:said carrying step includes using a center conducting line of said common conductor to transmit each of said power signal, said data signal and said command signal.
  • 6. A method, as claimed in claim 1, wherein:said providing step includes providing an operations-related signal that includes information related to at least one component of the antenna system and in which said operations-related signal is carried using said common conductor in a direction opposite that of said command signal.
  • 7. A method, as claimed in claim 1, wherein:said providing step includes receiving said command signal by modulating circuitry and using said power signal to power at least one component of said modulating circuitry.
  • 8. A method, as claimed in claim 1, wherein:said applying step includes applying said power signal to a number of transmit/receive modules, amplifiers and phase shifters of the antenna system.
  • 9. An apparatus for using different signals including supplying power to components of an antenna system, comprising:combining circuitry that joins together each of a power signal, a data signal and a command signal; a common conductor for carrying each of said power signal, said data signal and said command signal; separating circuitry electrically connected to said common conductor that separates said power signal, said data signal and said command signal; and antenna system circuitry electrically connected to said separating circuitry that receives at least said power signal and said command signal in which a number of components of the antenna system circuitry are supplied power by said power signal and in which operation of an antenna element associated with said antenna system circuitry is controlled by said command signal, wherein said command signal controls a phase of said data signal in order to steer a beam of said antenna element.
  • 10. An apparatus, as claimed in claim 9, wherein:said common conductor includes a center conducting line that can simultaneously transmit each of said power signal, said data signal and said command signal.
  • 11. An apparatus, as claimed in claim 9, wherein:said combining circuitry includes a first circuit assembly for joining said power signal with said command signal and for joining said power signal and said command signal with said data signal.
  • 12. An apparatus, as claimed in claim 9, wherein:said command signal includes a modulated command signal and said combining circuitry includes a second circuit assembly for generating said modulated command signal using said command signal that is input thereto.
  • 13. An apparatus, as claimed in claim 9, wherein:said power signal is carried by a power signal conducting line and said combining circuitry includes filter circuitry for preventing said command signal and said data signal from passing to said power signal conducting line.
  • 14. An apparatus, as claimed in claim 12, wherein:said data signal has a first frequency and said modulated command signal has a second frequency, with each of said first and second frequencies being different from each other.
  • 15. An apparatus, as claimed in claim 14, wherein:a modulated operations-related signal is transmitted using said common conductor in a direction opposite that of said command signal and in which said modulated operations-related signal has a third frequency different from each of said first and second frequencies.
  • 16. An apparatus for using different signals including supplying power to components of an antenna system, comprising:combining circuitry that joins together each of a power signal, a data signal and a command signal; a common conductor for carrying each of said power signal, said data signal and said command signal; separating circuitry electrically connected to said common conductor that separates said power signal, said data signal and said command signal; antenna system circuitry electrically connected to said separating circuitry that receives at least said power signal and said command signal in which a number of components of the antenna system circuitry are supplied power by said power signal and in which operation of an antenna element associated with said antenna system circuitry is controlled by said command signal; and modulating circuitry for modulating an operations-related signal that is provided using at least one component of said antenna system circuitry, said operations-related signal having a frequency different from each of said power signal, said data signal and said command signal and with said operations-related signal being carried by said common conductor in an opposite direction from that of said command signal, and said operations-related signal being indicative of status information associated with said one component.
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