# US 5,708,679 A · Hitless ultra small aperture terminal satellite communication network > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,708,679 A - Document ID: US5708679A - Status: Granted - Kind: A - Application number: 08/305,147 - Filed: 1994-09-13 - Granted: 1998-01-13 - Earliest claimed: 1993-03-11 - Assignees: Southern California Edison Company - Inventors: Roosevelt A. Fernandes; Kurt P. Krabbe; Haynes Ellis, Jr. - Web page: https://patentgrep.com/patent/US5708679A ## CPC - H01Q 21/0075: {Stripline fed arrays (H01Q21/065 takes precedence)} - H01Q 3/14: for varying the relative position of primary active element and a refracting or diffracting device - H01Q 3/267: {Phased-array testing or checking devices} - H01Q 21/062: {using dipole aerials; (H01Q21/067, H01Q21/068 take precedence)} - H04B 1/707: using direct sequence modulation - H04B 7/18528: {Satellite systems for providing two-way communications service to a network of fixed stations, i.e. fixed satellite service or very small aperture terminal [VSAT] system} - H04B 7/18578: {Satellite systems for providing broadband data service to individual earth stations (for selecting H04W; provisions for broadband connection, H04Q11/0478)} - H04B 7/216: Code division or spread-spectrum multiple access {[CDMA, SSMA]} - H01Q: ANTENNAS, i.e. RADIO AERIALS (radiators or antennas for microwave heating H05B6/72) - H04B: TRANSMISSION ## Abstract A communication network comprises multiple mini-hub terminals for transmitting and receiving information from multiple remote terminals. Some of the multiple mini-hub terminals, and some of the multiple remote terminals are capable of wireless communication respectively with each other through satellite communication means. A co-located terminal is hard wire connected with at least some of the mini-hub terminals. At least some of the terminals includes a flat antenna comprising a ground plane and a substrate forming at least one in flat array antenna mounted relative to the ground plane. The flat array antenna has multiple spaced dipoles formed on the substrate to constitute the array, and a transmission line formed on the substrate connecting the spaced dipoles. The transmission line is for connection with a link to a terminal with which communication is to be affected by signals through the antenna. A mobile antenna has beam steering lenses for forcing the signal. Also provided are sensors located on power transmission lines, the sensor being capable of measuring travelling waves on the lines, and communicating via an array antennal through a satellite at KU, KA-band or L-band frequencies, characteristics of the travelling wave thereby to facilitate fault location on the transmission lines. ## Claims ### Claim 1 An antenna for permitting communication to an earth orbiting satellite comprising: a ground plane, a substrate forming at least a pair of flat array antenna sets mounted relative to the ground plane, the flat array antenna sets having multiple spaced dipoles formed on the substrate to constitute the array, the sets being located in substantially planar relationship to each other, a transmission line formed on the substrate connecting the spaced dipoles, the transmission line being for connection with a link to a terminal with which communication is to be affected by signals through the antenna, and wherein the arrays of spaced dipoles are separated by at least one substrate, and the dipoles a symmetry or balanced pattern collectively providing for a gain sufficient to permit communication with a geostationary positioned satellite. ### Claim 2 (depends on 1) An antenna as claimed in claim 1 wherein the spaced dipoles are formed back-to-back on a substrate. ### Claim 3 (depends on 1) An array as claimed in claim 1 where each array is formed on its own substrate, and wherein the arrays are aligned relative to each other to form the antenna array. ### Claim 4 (depends on 1) An antenna as claimed in claim 1 including beam steering means, the beam steering means being cooperative with the array thereby to steer a beam emanating from the array within a predetermined field of view. ### Claim 5 An antenna comprising: a ground plane, a substrate forming at least a pair of flat array antenna sets mounted relative to the ground plane, the flat array antenna sets having multiple spaced dipoles formed on the substrate to constitute the array, the sets being located in substantially planar relationship to each other, a transmission line formed on the substrate connecting the spaced dipoles, the transmission line being for connection with a link to a terminal with which communication is to be affected by signals through the antenna, and wherein the arrays of spaced dipoles are separated by at least one substrate, and including beam steering means, the beam steering means being cooperative with the array thereby to steer a beam emanating from the array within a predetermined field of view, and wherein the beam steering means includes at least one rotatable lens, the lens acting to steer a beam within a conical field of view. ### Claim 6 (depends on 5) An antenna as claimed in claim 5 wherein the lens is a disk mounted relatively parallel to the substrate, the disk being rotatable about a central axis, and the disk being rotatable relative to the substrate about the axis. ### Claim 7 (depends on 6) An antenna as claimed in claim 6 including multiple substrates and multiple rotatable disk lenses for forming and steering a beam with the antenna. ### Claim 8 (depends on 6) An assembly for an antenna as claimed in claim 6 including a housing for substantially encasing the antenna within a unit. ### Claim 9 (depends on 8) An assembly as claimed in claim 8 including means for connecting a motor assembly with a shaft, the shaft protruding from the assembly and being connected with the lenses, the motor assembly causing rotation of the shaft thereby to cause rotation of the lenses to affect beam steering. ### Claim 10 An antenna for permitting communication to an earth orbiting satellite comprising: a substrate forming at least one in flat array antenna mounted relative to the ground plane, the flat array antenna having multiple spaced dipoles formed on the substrate to constitute the array, a transmission line formed on the substrate connecting the spaced dipoles, the transmission line being for connection with a link to a terminal with which communication is to be affected by signals through the antenna, means in the transmission line for interfacing with an unbalanced circuit whereby a flat antenna array representing a balanced circuit is effectively connected with the unbalanced circuit, and the dipoles collectively providing for a gain sufficient to permit communication with a geostationary positioned satellite. ### Claim 11 (depends on 10) An antenna as claimed in claim 10 including a tapered configuration in at least one transmission line on the antenna thereby to affect a relatively smooth interface between the balanced circuit and the unbalanced circuitry. ### Claim 12 An antenna for permitting communication to an earth orbiting satellite comprising: a substrate forming at least one in flat array antenna mounted relative to the ground plane, the flat array antenna having multiple spaced dipoles formed on the substrate to constitute the array, a transmission line formed on the substrate connecting the spaced dipoles, the transmission line being for connection with a link to a terminal with which communication is to be affected by signals through the antenna, the dipoles being formed by cladding a conductive material on a dielectric material, and the dipoles collectively providing for a gain sufficient to permit communication with a geostationary positioned satellite. ### Claim 13 (depends on 12) An antenna as claimed in claim 12 wherein the conductive material is etched on a flexible dielectric material and wherein the array is formed on at least one side of the dielectric material. ### Claim 14 (depends on 13) An antenna as claimed in claim 13 wherein the conductive material is etched on a flexible dielectric material and wherein the array is formed on at least one side of the dielectric material. ### Claim 15 An antenna comprising: a substrate forming at least one in flat array antenna mounted relative to the ground plane, the flat array antenna having multiple spaced dipoles formed on the substrate to constitute the array, a transmission line formed on the substrate connecting the spaced dipoles, the transmission line being for connection with a link to a terminal with which communication is to be affected by signals through the antenna, the dipoles being formed by cladding a conductive material on a dielectric material and wherein the array has a cross-section selectively regular or irregular in shape, and selectively being square, circular or rectangular. ### Claim 16 An antenna comprising: a substrate forming at least one in flat array antenna mounted relative to the ground plane, the flat array antenna having multiple spaced dipoles formed on the substrate to constitute the array, a transmission line formed on the substrate connecting the spaced dipoles, the transmission line being for connection with a link to a terminal with which communication is to be affected by signals through the antenna, the dipoles being formed by cladding a conductive material on a dielectric material and including a second array in spaced location relative to the first array, the spacing of the second array being selectively in a sandwich formation relative to the first array, or in side-by-side relationship with the first array, and wherein the first array is arranged for communication in a first frequency band, and the second array is arranged for communication in a second frequency band. ### Claim 17 An antenna comprising: a substrate forming at least one in flat array antenna mounted relative to the ground plane, the flat array antenna having multiple spaced dipoles formed on the substrate to constitute the array, a transmission line formed on the substrate connecting the spaced dipoles, the transmission line being for connection with a link to a terminal with which communication is to be affected by signals through the antenna, the dipoles being formed by cladding a conductive material on a dielectric material and wherein the array constitutes at least two sets of spaced dipoles in relationship with each other for communication in a selected frequency band, and wherein spaced dipoles for communication in the selected frequency band are spaced apart relative to each other a predetermined degree, and wherein the transmission means for each respective dipole set are selectively spaced apart from each other a predetermined degree, the spacing of the dipole and the transmission lines being determined according to the wavelength of the frequency band. ### Claim 18 (depends on 12) An antenna as claimed in claim 12 wherein the dipole geometry and transmission line geometry are determined according to the wavelength of the communication to be affected through the antenna. ### Claim 19 (depends on 12) An antenna as claimed in claim 12 including means for affecting polarization of the signal communicated through the antenna. ### Claim 20 An antenna comprising: a substrate forming at least one in flat array antenna mounted relative to the ground plane, the flat array antenna having multiple spaced dipoles formed on the substrate to constitute the array, a transmission line formed on the substrate connecting the spaced dipoles, the transmission line being for connection with a link to a terminal with which communication is to be affected by signals through the antenna, the dipoles being formed by cladding a conductive material on a dielectric material and including means for affecting an impedance match between the antenna and a connection with a terminal with which the antenna transmission line is connected. ### Claim 21 (depends on 12) An antenna as claimed in claim 12 including means for affecting polarization of a signal, the polarization being selectively in a horizontal, vertical, or circular mode. ### Claim 22 An antenna comprising: a substrate forming at least one in flat array antenna mounted relative to the ground plane, the flat array antenna having multiple spaced dipoles formed on the substrate to constitute the array, a transmission line formed on the substrate connecting the spaced dipoles, the transmission line being for connection with a link to a terminal with which communication is to be affected by signals through the antenna, the dipoles being formed by cladding a conductive material on a dielectric material and including forming the dipoles to constitute an array for permitting communication at more than one wavelength band. ### Claim 23 (depends on 22) An antenna as claimed in claim 22 wherein the dipoles include a bow-tie configuration thereby permitting communication over two disparate frequency bands. ### Claim 24 (depends on 23) An antenna as claimed in claim 23 wherein the transmission line is connected substantially midway between extremities of the bow-tie configuration, such that a half of the bow-tie would constitute one limb of a dipole and the other half of the bow-tie a second limb of the dipole. ### Claim 25 An antenna comprising: a substrate forming at least one in flat array antenna mounted relative to the ground plane, the flat array antenna having multiple spaced dipoles formed on the substrate to constitute the array, a transmission line formed on the substrate connecting the spaced dipoles, the transmission line being for connection with a link to a terminal with which communication is to be affected by signals through the antenna, the dipoles being formed by cladding a conductive material on a dielectric material and including a second flat array arranged in relationship relative to the first array, and wherein dipoles of the first array are directed in a first direction for communication in a first frequency band, and dipoles of a second array are arranged transversely with the first dipoles to affect communication in a second frequency band, and wherein the dipoles for each frequency band includes a ground plane and set of dipoles arranged in an orientation opposite to the dipoles for each respective frequency band. ### Claim 26 An antenna comprising: a substrate forming at least one in flat array antenna mounted relative to the ground plane, the flat array antenna having multiple spaced dipoles formed on the substrate to constitute the array, a transmission line formed on the substrate connecting the spaced dipoles, the transmission line being for connection with a link to a terminal with which communication is to be affected by signals through the antenna, the dipoles being formed by cladding a conductive material on a dielectric material and wherein the dipoles are constituted by a substantially square U-shaped element, the outer limbs of the U being determined according to the wavelength of the frequency of communication, and a middle limb of the U being connected with a transmission line for the network. ### Claim 27 A communication network for permitting communication to an earth orbiting satellite comprising: multiple mini-hub terminals for transmitting information, multiple remote terminals, at least some of the multiple mini-hub terminals, and at least some of the multiple remote terminals being capable of wireless communication respectively with each other through satellite communication means, and a co-located terminal hard wire connected with at least some of the multiple mini-hub terminals, the co-located terminal also being in communication with the satellite communication means for facilitating coordination of signals received from at least one of the remote terminals, at least some of the remote terminals including an antenna having a substrate forming at least one in flat array antenna mounted relative to the ground plane, the flat array antenna having multiple spaced dipoles formed on the substrate to constitute the array, a transmission line formed on the substrate connecting the spaced dipoles, the transmission line being for connection with a link to a terminal with which communication is to be affected by signals through the antenna, and the dipoles collectively providing for a gain sufficient to permit communication with a geostationary positioned satellite. ### Claim 28 A communication network comprising: multiple mini-hub terminals for transmitting information, multiple remote terminals, at least some of the multiple mini-hub terminals, and at least some of the multiple remote terminals being capable of wireless communication respectively with each other through satellite communication means, and a co-located terminal hard wire connected with at least some of the multiple mini-hub terminals, the co-located terminal also being in communication with the satellite communication means for facilitating coordination of signals received from at least one of the remote terminals, at least some of the remote terminals including an antenna having a substrate forming at least one in flat array antenna mounted relative to the ground plane, the flat array antenna having multiple spaced dipoles formed on the substrate to constitute the array, a transmission line formed on the substrate connecting the spaced dipoles, the transmission line being for connection with a link to a terminal with which communication is to be affected by signals through the antenna, and means in the antenna means for communicating with GPS signals thereby to provide antenna orientation for peak directivity with a satellite. ### Claim 29 A communication network for permitting communication to an earth orbiting satellite comprising: multiple mini-hub terminals transmitting information, multiple remote terminals, at least some of the multiple mini-hub terminals, and at least some of the multiple remote terminals being capable of wireless communication respectively with each other through satellite communication means, at least some of the terminals including an antenna having a ground plane, a substrate forming at least one in flat array antenna mounted relative to the ground plane, the flat array antenna having multiple spaced dipoles formed on the substrate to constitute the array, a transmission line formed on the substrate connecting the spaced dipoles, the transmission line being for connection with a link to a terminal with which communication is to be affected by signals through the antenna, and the dipoles collectively providing for a gain sufficient to permit communication with a geostationary positioned satellite. ### Claim 30 A communication network comprising: multiple mini-hub terminals for transmitting information, multiple remote terminals, at least some of the multiple mini-hub terminals, and at least some of the multiple remote terminals being capable of wireless communication respectively with each other through satellite communication means, at least some of the terminals including an antenna having a ground plane, a substrate forming at least one in flat array antenna mounted relative to the ground plane, the flat array antenna having multiple spaced dipoles formed on the substrate to constitute the array, a transmission line formed on the substrate connecting the spaced dipoles, the transmission line being for connection with a link to a terminal with which communication is to be affected by signals through the antenna, and means in the antenna means for communicating with GPS signals thereby to provide antenna orientation for peak directivity with a satellite. ### Claim 31 A method of communicating between multiple mini-hub terminals for transmitting information and multiple remote terminals comprising: having at least some of the multiple mini-hub terminals, and at least some of the multiple remote terminals being capable of wireless communication respectively with each other through satellite communicator; hard wire connecting a co-located terminal with at least some of the multiple mini-hub terminals, the co-located terminal also communicating with the satellite communicator for facilitating coordination of signals received from at least one of the remote terminals; hard wiring respective multiple co-located terminals with respective multiple mini-hub terminals, and each remote terminal communicating with a respective mini-hub terminal through the satellite communicator means whereby two-way communication between multiple remote terminals and multiple mini-hub terminals is affected; receiving packets of information from multiple mini-hub terminals, and the multiple mini-hub terminals in turn communicating with remote terminals, and the respective multiple mini-hub terminals communicating with other mini-hub terminals in the multiple mini-hubs through a co-located remote terminal hard wire connected with the respective mini-hub terminal; communicating from the mini-hub terminals by spread spectrum encoding thereby to reduce spectral density and permit reception of the signal by a small aperture antenna, the small aperture antenna being associated with respective remote terminals; communicating from the mini-hub terminals packets of information, the packets being transmitted sequentially within an allocated time slot thereby creating a time division multiple access communication system; receiving the respective remote terminals the packets of information communicated from the mini-hub terminal, the packets representing a non-continuous signal, each in part transmitted by different mini-hub terminals; and acquiring the spread spectrum code phase and signal frequency with minimum loss of transmission time, and the signals being transmitted by respective mini-hub terminals being relatively close to one another with regard to signal frequency and spread spectrum code phase. ### Claim 32 A method of communicating comprising between multiple mini-hub terminals for transmitting information and multiple remote terminals comprising: having at least some of the multiple mini-hub terminals, and at least some of the multiple remote terminals being capable of wireless communication respectively with each other through satellite communicator; hard wire connecting a co-located terminal with at least some of the multiple mini-hub terminals, the co-located terminal also communicating with the satellite communicator for facilitating coordination of signals received from at least one of the remote terminals; receiving information packets from multiple mini-hub terminals, and the multiple mini-hub terminals in turn communicating between multiple remote terminals, and the multiple mini-hub terminals communicating respectively with each other through a respective co-located remote terminal associated with the respective mini-hub terminals; detecting packets of data, and wherein the detection of a missing packet of data from a remote terminal to a mini-hub terminal is indicative of a failure of a mini-hub terminal corresponding to the missing packet; and redesignating a mini-hub terminal to compensate for a failed mini-hub terminal. ### Claim 33 A method of communicating through a communication terminal, at least in part, through satellite communicator comprising sensing temperature at the remote terminal, the terminal utilizing a local reference frequency for acquisition and tracking of a received carrier frequency from the satellite communicator coupling the temperature sensing to a reference frequency, and controlling the voltage of the reference frequency to maintain a match to a carrier frequency received from the satellite communicator, determining and storing the controlled voltage versus temperature in a memory of the terminal, and relating the controlled voltage relative to the temperature thereby to develop a calibration for maintaining a match between the local reference frequency and the carrier frequency. ### Claim 34 A method of communicating through a communication network between multiple mini-hub terminals for transmitting information and multiple remote terminals comprising: having at least some of the multiple mini-hub terminals, and at least some of the multiple remote terminals of wireless communicate respectively with each other through satellite communicator; hard wire connecting a co-located terminal with at least some of the multiple mini-hub terminals, the co-located terminal also communicating with the satellite communicator for facilitating coordination of signals received from at least one of the remote terminals, sensing temperature at the remote terminal, the terminal including utilizing a local reference frequency for acquisition and tracking of a received carrier frequency from the satellite communicator; coupling the temperature sensing to the reference frequency, and controlling the voltage of the reference frequency to maintain a match to a carrier frequency received from the satellite communicator; determining and storing the controlled voltage versus temperature in a memory of the terminal; and relating the controlled voltage relative to the temperature thereby to develop a calibration for maintaining a match between the local reference frequency and the carrier frequency. ### Claim 35 A method of communicating to an earth orbiting satellite comprising: sensing from a location in relatively close relationship with a power transmission line, communicating from the sensor; measuring, through the sensing, at least one electrical parameter associated with the power transmission line; locating an antenna on the sensor for communicating a sensed parameter through a wireless communication with a remote location, the antenna being an array located in a planar manner on a surface of the sensor, the array including multiple spaced dipoles formed substantially parallel with the surface, and the dipoles collectively providing a gain sufficient to permit communication with a geostationary positioned satellite. ### Claim 36 A method of communicating to an earth orbiting satellite comprising: locating at least one sensor in relatively close relationship with a power transmission line, communicating from the sensor, measuring, through the sensor, at least one electrical parameter associated with the power transmission line, locating an antenna in association with the sensor for communicating a sensed parameter through a wireless communication with a remote location, the antenna being a flat array located on a surface of the sensor, the array including multiple spaced dipoles formed substantially parallel with the surface; synchronizing on the sensor, signals from the sensor with a GPS signal; tagging a traveling wave on a power transmission line in relation to time thereby to facilitate measuring the location of a fault on a power transmission line, and the dipoles collectively providing a gain sufficient to permit communication with a geostationary positioned satellite. ### Claim 37 (depends on 31) A method as claimed in claim 31 wherein respective remote terminals co-located with respective mini-hub terminal communicate data packets received from the satellite communication plus variations in spread spectrum code phase and signal frequency to the respective mini-hub terminal with which the co-located terminal is hard wired. ### Claim 38 (depends on 31) A method as claimed in claim 31 including designating a selected one of the multiple mini-hub terminals as a master terminal, and having other mini-hub terminals of the network adjust a respective spread spectrum code phase and frequency thereby to align with the designated master mini-hub terminal. ### Claim 39 (depends on 33) A method as claimed in claim 33 including establishing a table relating the reference frequency and voltage relative to temperature. ### Claim 40 (depends on 39) A method as claimed in claim 39 including applying an adaptive algorithm at least in part to eliminate input from the table, the adaptive algorithm being operative after establishing a calibration of the remote. ### Claim 41 (depends on 40) A method as claimed in claim 40 including having in the table a relationship between temperature and extended time periods thereby to update the table over extended time periods, and optionally in the algorithm for affecting adaptive temperature compensation. ### Claim 42 (depends on 41) A method as claimed in claim 41 including sensing in the terminal the absence of a signal or condition normally present at the terminal, measuring the temperature and applying selectively the table or algorithm for establishing a reference frequency control voltage thereby to facilitate reacquisition of communication of a terminal with a carrier frequency. ### Claim 43 (depends on 34) A method as claimed in claim 34 wherein the satellite communication is affected by applying a GPS time standard for communication between the mini-hub terminals and the remote terminals, and including, at the remote terminals, affecting adaption of the remote terminal in response to temperature variations within about one microsecond thereby to promote acquisition of carrier signals between many hub terminals and remote terminals. ### Claim 44 A method of sensing a parameter on a power transmission line and communicating to an earth orbiting satellite comprising: mounting a sensor on a power transmission line, sensing and measuring a parameter associated with the power transmission line; locating an antenna on the sensor for communicating with a remote location; forming the antenna with a substantially flat array to have multiple spaced dipoles on a substrate to constitute the array; relating the time of parameter measurement relative to a GPS timing signal, and the dipoles collectively providing a gain sufficient to permit communication with a geostationary positioned satellite. ### Claim 45 (depends on 35) A method as claimed in claim 35 wherein the measured parameter is a traveling wave propagated on the power transmission line, the characteristic of the wave being for determining the location of a fault in relationship to the power transmission line at a predetermined location relative to the sensor. ### Claim 46 (depends on 45) A method as claimed in claim 45 wherein there are multiple power transmission lines in substantial parallel location relative to each other, and wherein sensing on each power line a parameter for the multiple power transmission lines. ### Claim 47 (depends on 36) A method as claimed in claim 36 wherein the sensed parameter includes at least one of phase angle, voltage, or current associated with the power transmission line. ### Claim 48 (depends on 46) A method as claimed in claim 46 wherein the sensed parameter includes at least one of phase angle, voltage, or current associated with the power transmission line. ### Claim 49 A method of communicating comprising: sensing from a location in relatively close relationship with a power transmission line, communicating from the sensor; measuring, through the sensing, at least one electrical parameter associated with the power transmission line; locating an antenna On the sensor for communicating a sensed parameter through a wireless communication with a remote location, the antenna being an array located in a planar manner on a surface of the sensor, the array including multiple spaced dipoles formed substantially parallel with the surface, and synchronizing measurement signals with a GPS signal, and tagging a traveling wave on a power transmission line in relation to time thereby to facilitate measuring the location of a fault on a power transmission line. ### Claim 50 (depends on 46) A method as claimed in claim 46 including sensing synchronizing signals with a GPS signal, and tagging a traveling wave on a power transmission line in relation to time thereby to facilitate measuring the location of a fault on a power transmission line. ### Claim 51 A method of communicating on a network comprising: locating at least one sensor in relatively close relationship with a power transmission line, communicating with a sensor, measuring at least one electrical parameter associated with the power transmission line, communicating a sensed parameter through a wireless communication with a remote location, and wherein the sensor is a flat array located on a surface of the sensor, the array including multiple spaced dipoles formed substantially parallel with the surface; synchronizing signals from the sensor with a GPS signal; and tagging a traveling wave on a power transmission line in relation to time thereby to facilitate measuring the location of a fault on a power transmission line. ### Claim 52 (depends on 51) A method as claimed in claim 51 wherein the traveling wave is measured in respect of each of the power transmission lines, and calculating characteristics in relation to each of the power transmission lines thereby to facilitate determination of the location of a fault in relationship to one or more of the power transmission lines. ### Claim 53 (depends on 1) An antenna as claimed in claim 1 wherein there is a relatively broad frequency band. ### Claim 54 (depends on 1) An antenna as claimed in claim 1 wherein the beam pattern from the antenna is relatively narrow. ### Claim 55 (depends on 1) An antenna as claimed in claim 1 wherein the gain of the antenna is at least about 10 dB, and preferably about 20 to 30 dB. ### Claim 56 (depends on 1) An antenna as claimed in claim 1 including collocated dual-frequency orthogonal polarized arrays with twin-lead transmission lines. ### Claim 57 (depends on 5) An antenna as claimed in claim 5 wherein the transmission line is tapered for effecting impedance matching. ### Claim 58 (depends on 4) An antenna as claimed in claim 4 wherein the dipoles present a substantially symmetrical pattern.