Abstract: A radar apparatus that detects an object using radiated waves includes: an antenna surface that includes an element unit that emits a radiated wave for a radar; and a cover member that covers the antenna surface to protect the element unit. The cover member includes an inner refractive surface that is an inner side surface of the cover member on which an undesired wave is incident and is formed into a shape that refracts the undesired wave incident on the inner refractive surface so as to advance towards antenna rear. The antenna rear is a side opposite an antenna front that is a side on which the radiated wave is emitted, with the antenna surface as a boundary. Undesired waves are radiated waves that are emitted outside a range of a predetermined solid angle relative to a normal direction of the antenna surface from a center of the antenna surface from which the radiated waves are emitted.

Abstract: A near-field test system for a phased array antenna includes a probe, a beam forming network, and a computing system. The probe is disposed at a fixed position in a near-field of the antenna and is configured to receive at least a portion of a test beam radiated by the antenna. The beam forming network is coupled to the antenna and includes a plurality of phase shifters configured to steer the test beam to a position in the near-field when radiated by an array of antenna elements of the antenna. The computing system is coupled to the probe and is configured to normalize received power of the test beam based on the position of the beam in the near-field relative to the fixed position of the probe, and generate a far-field antenna pattern for the antenna from normalized received power of the test beam.

Abstract: A network communication system includes three or more nodes that are wirelessly connected in a mesh configuration, forming a reconfigurable mesh network, to improve communication link performance. The reconfigurable mesh network can be dynamically adjusted to maintain and improve communication links throughout a region serviced by the mesh, or between a source and destination on the mesh network. Adaptive antenna system techniques are implemented in one or more of the nodes on the mesh network, such that multiple radiation pattern modes can be generated to dynamically adjust radiated performance between specific links along a selected path for communicating information on the mesh network. Antenna system metrics, such as signal to noise ratio, signal to interference plus noise ratio, and receive signal strength indicator are used to monitor and to adjust adaptive antenna system characteristics to optimize link performance between nodes on the mesh network.

Abstract: An antenna structure includes a curved base and a plurality of multi-input multi-output (MIMO) antenna cell. The curved base has a convex curved surface. The MIMO antenna cells are uniformly and movably located on the convex curved surface. Each of the MIMO antenna cells has receiving units and transmission units.

Abstract: Described embodiments provide methods and apparatus for processing radio-frequency (RF) signals using a photonic integrated circuit (PIC). The PIC comprises a substrate having integrated lasers and signal paths. Each signal path is configured to receive a single laser signal from the lasers. Each signal path comprises an electro-optic modulator (EOM), an optical butler matrix, and a photodetector. The EOM is communicatively coupled to the one or more lasers and is configured to generate an output optical signal by modulating the single laser signal based on an input radio frequency (RF) signal. The optical butler matrix is communicatively coupled to each of the one or more signal paths and is configured to generate an optical beamformed signal from the output optical signal. The photodetector is configured to convert the optical beamformed signal to an output RF signal.

Abstract: A passive frequency multiplexer includes a beam forming network lens including a plurality of input terminals and a plurality of output terminals; a transmission line for transmitting a signal to the beam forming lens; and a plurality of couplers arranged in series along the transmission line, each of the plurality of couplers comprising an input terminal, an output terminal, and a coupled output terminal, each of the coupled output terminals of the plurality of couplers being coupled to a respective one of the input terminals of the beam forming network lens.

Abstract: Aspects of the invention provide improvements to electromagnetic and other wave-based ranging systems, e.g., RADAR or LIDAR systems, of the type having transmit logic that transmits a pulse based on an applied analog signal. The improvements are characterized, in part, by a SERDES having a serializer (a/k/a a “transmit side”) that is coupled to the transmit logic. The serializer has (i) an input to which a pattern on which the pulse is based is applied and (ii) an output from which a serialization of the pattern is applied to the transmit logic. The improvements are further characterized in that the SERDES has deserializer logic (a/k/a a “receive side”) that is coupled to receive logic and that deserialize a received “analog” signal containing possible reflections of the pulse.

Abstract: Methods and Systems for testing phased antenna arrays include positioning a phased antenna array and a probe antenna at relative positions with respect to each other where one of them can operate as the transmitter and the other as the receiver. The transmitter can radiate a plurality of electromagnetic waves sequentially while the phased antenna array is steered or configured differently for each radiated electromagnetic. The receiver can receive, responsive to each radiated electromagnetic wave, a corresponding receive radio frequency (RF) signal. A processor can determine one or more performance parameters of the phased antenna array using the receive RF signals.

Abstract: A system includes a phased array antenna. The phased array antenna includes a rear panel that has: a first array of phase shift elements; and a second array of rear antenna elements. The phased array antenna also includes a front panel that has a third array of front antenna elements. Each of the front antenna elements is electrically coupled to a corresponding one of the rear antenna elements through one of the phase shift elements. When the second array of rear antenna elements receives a radio signal from a base station and the first array of phase shift elements receives an optical control beam from the base station, the third array of antenna elements radiates an output radio signal in a direction indicated by the optical control beam.

Abstract: A quasi-optical beamformer includes a power distributor composed of a succession of parallel-plate dividers extending in a YZ-plane from a first stage to a last stage, each parallel-plate divider comprising, in each of the stages of the corporate structure located under a higher stage, first and second parallel-plate waveguide branches leading to respective parallel-plate dividers of the following stage of the corporate structure, the beamformer furthermore including a plurality of lenses extending longitudinally along the X-axis in at least one stage of the power distributor, so as to apply a delay that is continuously variable along the X-axis, the lenses being placed in each of the branches of the dividers of at least one stage in the power distributor.

Abstract: An antenna device is provided. The antenna device includes a reflector having a profile of a parabolic shape in a first cross-section cut parallel to a first direction and a profile of a hyperbolic shape in a second cross-section, the second cross-section being cut perpendicular to the first direction and crossing the first cross-section at a right angle and a radiating structure having at least one phased antenna array adapted to illuminate at least part of the reflector and to scan a beam. The edges of the profile of the parabolic shape of the first cross-section are formed to be directed toward the radiating structure. The edges of the profile of the hyperbolic shape of the reflector are formed to be directed away from the radiating structure. The antenna device may be diversified depending on various embodiments.

Abstract: A sparse phase-mode feed network for an antenna array is described. The waveguide assembly includes a plurality of radiating element probes for coupling to respective radiating elements of the antenna array, and a plurality of phase-mode feed probes. A variable phase shifter is positioned in the waveguide assembly in an annular region between the radiating element probes and the phase-mode feed probes to cause additional progressive electrical phase shifts of the radiating elements of the antenna array from 0 to 2?K radians, the phase shift progressing for one complete physical angular cycle in the plane of the waveguide assembly. A beam forming network couples the phase-mode feed probes to a plurality of phase-mode feed ports corresponding to respective consecutive-order phase modes of the antenna array. When coupled to the antenna array, respective orders of the phase modes provided at the phase-mode feed ports are selectable in accordance with K.

Abstract: A wireless telecommunications system that employs a distributed-antenna system is described in which different combinations of radio signals are assigned to antennas so as to facilitate locating a wireless terminal based on the identity and the relative signal strength of the radio signals it receives above a signal-strength threshold.

Abstract: Aspects of the subject disclosure may include, a system that can transmit first wireless signals associated with communication signals, where the first wireless signals are directed via beam steering by an antenna array towards a wireless receiver. The system can transmit second wireless signals associated with the communication signals, where the second wireless signals are directed via the beam steering by the antenna array towards a transmission medium. The second wireless signals can induce electromagnetic waves at a physical interface of the transmission medium where the electromagnetic waves are associated with the communication signals. Other embodiments are disclosed.

Abstract: A telecommunications system is provided that is controllably operable as a sectorized antenna system and as an omnidirectional antenna system without requiring hardware reconfiguration. The telecommunications system includes a phase correlation measurement unit that can be between a sectorized antenna sub-system and a remotely located RF source site. The phase correlation measurement unit can be coupled to the RF source site over at least one feed line. The phase correlation measurement unit can output signals for controlling a phase shifter at the RF source site for phase shifting downlink signals and for causing operation of the sectorized antenna sub-system as an omnidirectional antenna sub-system. In a sectorized operation mode, the phase correlation measurement unit and the phase shifter can be inactivated.

Abstract: A method and apparatus for phase-mode feeding a circular antenna array for beamsteering is provided. A Butler Matrix having M antenna-side ports and M input/output ports is coupled to beamsteering circuitry. The coupled input/output ports may include a port corresponding to a phase-mode having an order magnitude greater than one. The coupled input/output ports may include ports of three different order magnitudes of phase-mode. The Butler Matrix is coupled to M inner ports of a radial waveguide, and the antenna elements are coupled to N outer ports of the waveguide, where N>M. Where M=4, the input/output ports correspond to a zeroth order phase-mode, plus and minus 1st order phase-modes, and a second order phase-mode. The zeroth order phase-mode may be used for beamsteering closer to the radial axis of the antenna array while the second order phase-mode may be used for beamsteering further from the radial axis.

Abstract: A wireless telecommunications system that employs a distributed-antenna system is described in which different combinations of radio signals are assigned to antennas so as to facilitate locating a wireless terminal based on the identity and the relative signal strength of the radio signals it receives above a signal-strength threshold.

Abstract: Aspects of the subject disclosure may include, for example, receiving, by each of a plurality of receivers, one of a plurality of electromagnetic waves, each electromagnetic wave of the plurality of electromagnetic waves guided by a different one of a plurality of twin-lead transmission lines, each twin-lead transmission line sharing a wire, and each electromagnetic wave of the plurality of electromagnetic waves including a different one of a plurality of communication signals, and obtaining, by each of the plurality of receivers, one of the plurality of communication signals. Other embodiments are disclosed.

Abstract: A distributed directional aperture (DDA) system provides the capability to receive and/or transmit signals, limiting that reception or transmission to a 3-dimensional beam. The DDA system includes sensing and/or emitting array subsystems which comprise sensors and/or emitters distributed across, within, or under the skin of an aircraft, ship, ground vehicle, or fixed installation. The sensors receive energy, convert the received signals to digital information, and transmit that information via a telemetry subsystem to a beamformer subsystem. The beamformer subsystem analyzes the received signals from the sensors and/or emitters in order to determine the signal content from a specific direction. The emitters transmit energy, converting signals received from the beamformer subsystem via the telemetry subsystem into energy emissions. Methods of providing the DDA system including subsystems thereof are also disclosed.

Abstract: A ship-based over-the-horizon (OTH) radar system provides mobile, persistent, wide-area air and ship surveillance across large ocean expanses and in anti-access/area denial (A2AD) environments. A transmit ship may include a log-periodic antenna (LPA) array adapted for use on a ship and a receive ship may include a plurality of monopole or dipole whip antennas. The transmit/receive antenna is fronted by a ground screen, which can be sized taking into account the sea as a naturally reflective surface. The transmit/receive ship can include advanced software to compensate for ship movement and synthetic aperture radar (SAR) techniques can be employed to includes the effective size of the radar receiver aperture. A modular design, using standard commercial container ships and shipping containers, allows for rapid deployment/stowage of radar equipment. Related methods are also described.

Abstract: Various embodiments of a millimeter-wave wireless point-to-point or point-to-multipoint communication system which enables determining preferred directions of transmissions, and transmitting in such preferred directions without routing radio-frequency signals. The system comprises a millimeter-wave focusing element, multiple millimeter-wave antennas, and multiple radio-frequency-integrated circuits (“RFICs”). In various embodiments, preferred directions are determined, and millimeter-wave beams are transmitted in the preferred directions.

Abstract: A transmitter-side estimation of the complex channel influence between function variable value transmitters and function receivers is limited to the estimation of the magnitude of the channel influence, so that a pre-distortion of the symbols of the symbol sequences depends on an inverse of the magnitude of the channel influence, but is independent of a phase of the channel influence. Easing the channel estimation does not change the central tendency of the calculated function results transmitted over the multiple channel. Alternatively, on the side of the function receiver, a statistical quantity describing the multiple-access channel is determined. For this purpose, it is sufficient when the function variable value transmitters transmit constant power signals over the multiple-access channel in a channel estimation phase. Thus, the channel estimation effort is transferred to the function receiver and hence occurs less frequently, which again reduces the overall energy expenditure.

Abstract: An antenna array for use within a microwave imaging system to capture a microwave image of a target is selectively programmed to optimize one or more parameters of the microwave imaging system. The array includes a plurality of antenna elements, each capable of being programmable with a respective phase shift to direct a beam of microwave radiation toward the target such that the microwave radiation from each of the plurality of antenna elements arrives at the target substantially in-phase. To optimize a parameter of the microwave imaging system, the phase shifts of selective ones of the antenna elements are altered, while still maintaining the substantially in-phase microwave radiation at the target.

Abstract: A transmission and reception module according to one embodiment of the present invention includes an antenna, a transmission circuit, a wave detection circuit, a high-frequency switch, a small-signal high-frequency diode limiter circuit, and a first power amplifier. The antenna transmits a transmission wave, or receives a reception wave. The transmission circuit is connected to the antenna via a circulator and supplies the transmission wave to the antenna. The wave detection circuit is connected to the antenna via the circulator and branches the reception wave received by the antenna to generate a control signal based on one branched reception wave. The high-frequency switch is connected to the wave detection circuit and suppresses a power of the other branched reception wave when the control signal is input thereto.

Abstract: Systems and methods for operating a communications system. The methods involve computing one or more complex weights to be applied to transmit signals and receive signals by beamformers. The complex weights are based at least on configuration data for the communications system. The methods also involve applying a first plurality of weight corrections to the complex weights based on phasing errors occurring in a communication path inclusive of a control system and antenna elements. The methods further involve applying a second plurality of weight corrections to the complex weights based on phase differences at the antenna elements relative to a reference location for the receive signals.

Abstract: A radio frequency (RF) phased array transmitter system comprises a phased array for generating an RF signal. The phased array comprises conductive patches formed in an array, separation gaps, and active sources. Each of the separation gaps is formed between two adjacent ones of the conductive patches, and each of the active sources is formed across its associated one of the separation gaps. The system further comprises an optical source for generating an optical signal and an RF source for generating an RF signal. In addition, the system comprises an optical modulator coupled to the optical source and the RF source. The optical modulator receives an optical signal and an RF signal, and produces an RF modulated optical signal based on the received optical signal and the received RF signal.

Abstract: A system for a satellite includes a core system and multiple nodes for generating an active phased array. Each node includes a transceiver for wirelessly receiving a transmit signal from the core system, for wirelessly transmitting the transmit signals to a target, for wirelessly receiving the receive signals from the target, and for wirelessly transmitting the receive signal back to the core system. The system also includes a subsystem for inhibiting signal interference between the transmit and receive signals. Each of the nodes may also include local power generation circuitry.

Abstract: A system and methods for radar and communications applications. In one embodiment the present system comprises a wireless, space-fed, phased array of antennas including a plurality of unit cells. A first one of the unit cells includes a first one of the antennas and a unit cell command interpreter configured to receive a command, determine whether the command is intended for the first unit cell, and relay the command to logic for enabling a phase shift controller of the first antenna. In one embodiment the present methods comprise the step of wirelessly beaming microwave power from a power and control beam transmit unit to illuminate a wireless, space-fed, phased array of antennas including a plurality of unit cells. The method further comprises the steps of beaming a command to the array and converting the microwave power into direct current within a first one of the unit cells. The first unit cell includes a first one of the antennas.

Abstract: An improved millimeter wave illumination system includes at least one primary source of millimeter wave radiation, a reflecting surface and a baffle comprising a plurality of exit apertures arranged such that at least some of the radiation from the source is reflected from the reflective surface before proceeding to the baffle, characterized in that means are incorporated for generating a plurality of radiation field states within a pre-determined time interval. The baffle, source and reflector are preferably packaged into a container with the exit apertures providing an illumination output. The generation of the plurality of radiation field states provides an illumination at the illuminator output that is less spatially variable when integrated over the pre-determined time interval.

Abstract: A receiver, such as a miniaturized microwave-photonic coherent receiver (MMPR) is disclosed. The receiver includes an antenna to output an electrical RF signal received on a section of the antenna, a laser to produce an optical signal, a photonic modulator to receive the optical signal and the electrical RF signal and produce an EO-RF signal and to receive the optical signal and an electrical LO signal and produce an EO-LO signal, a signal combiner to provide a combined EO-RF and EO-LO signal and a photodiode to receive the combined signal and produce an IF signal. A method of detecting an object using the MMPR includes receiving an electrical RF signal corresponding to the object, outputting the electrical RF signal to a photonic modulator, modulating the electrical RF signal onto an optical carrier, demodulating the electrical RF signal to produce an IF signal and processing the IF signal.

Abstract: A signal simulation device for testing and developing radio receivers adapted to orientate antenna beams to different radio transmitters and to simultaneously suppress interference signals, comprises an antenna array, a signal generator generating reproducible digital signals in the complex baseband, and a digital matrix processor combined and synchronized with the signal generator. The processor has input signals generated by the signal generator and has output signals that form received signals of the antenna array. The input signals of the matrix processor are phase shifted according to a direction of incidence and to relative positions of the elements within the antenna array of the radio receiver, and are combined and supplied to outputs of the matrix processor. Amplitude and phase shift are simulated by weighting of the input signals from the signal generator, the weighting coefficients being calculated on a control computer and input into the matrix processor via an interface.

Abstract: An illumination source of predominantly non-directional and incoherent millimeter-wave radiation for illuminating an area for passive millimeter-wave imaging comprises a container with at least a partly reflective internal surface and a plurality of exit apertures and a primary source of millimeter-wave radiation for emitting millimeter-wave radiation into the container. The primary source and the container are arranged so that a proportion of the millimeter-wave radiation emitted by the source undergoes reflection within the container before being emitted through the apertures, such that the different paths lengths are at least equal to the coherence length of the radiation. This is facilitated if the bandwidth of the radiation is preferably at least 1 GHz. The container may be a box in which a waveguide is used to couple radiation from the primary source into the box. Alternatively, the container may be formed from a mesh and the plurality of holes is provided by the holes in the mesh.

Abstract: An antenna array for use within a microwave imaging system includes a plurality of reflecting antenna elements, each capable of being programmed with respective phase-shifts in a first pattern to direct a first beam of microwave radiation towards a first target, and each being capable of being programmed with respective phase-shifts in a second pattern to direct a second beam of microwave radiation towards a second target. To capture a microwave image of an object, the antenna elements are programmed with respective phase-shifts in an interleaved pattern including a portion of the first pattern and a portion of the second pattern.

Abstract: A scanning panel for use in a microwave imaging system captures a microwave image of a target using two complementary arrays of antenna elements. Each of the antenna elements in a first array is capable of being programmed with a respective phase delay to direct a transmit beam of microwave illumination toward the target in a transmit beam pattern, and each of the antenna elements in a second array is capable of receiving reflected microwave illumination reflected from the target in a receive beam in a receive beam pattern complementary to the transmit beam pattern. The microwave image of the target is formed at an intersection between the transmit beam and the receive beam.

Abstract: An antenna system, to enable communication with a moving vehicle via a satellite, utilizes an array of subarrays contiguously positioned in a diamond-type pattern. Straight edge boundaries of an array can maximize sidelobe degradation resulting from diffraction effects at the edge. The diamond-type array pattern provides saw tooth array edge boundaries with all edge portions at 45 degrees (or other suitable acute angle) to the principal array dimension (the length dimension). Uniform excitation may be provided for all subarrays via a binomial power divider/combiner configuration. Mechanical beam steering can be provided in azimuth and elevation. A phase shifter assembly may be provided to enable a limited electronic scan (e.g., plus or minus 2 degrees) to increase beam steering agility from a moving vehicle. Thin flat-plate subarray design details are provided.

Abstract: A microelectromechanical system (MEMS) steerable electronically scanned lens array (ESA) antenna and method of frequency scanning are disclosed. The MEMS ESA antenna includes a wide band feedthrough lens and a continuous transverse stub (CTS) feed array. The wide band feedthrough lens includes first and second arrays of wide band radiating elements and an array of MEMS phase shifter modules disposed between the first and second arrays of radiating elements. The continuous transverse stub (CTS) feed array is disposed adjacent the first array of radiating elements for providing a planar wave front in the near field. The MEMS phase shifter modules steer a beam radiated from the CTS feed array in two dimensions.

Abstract: A microelectromechanical system (MEMS) steerable electronically scanned lens array (ESA) antenna and method of frequency scanning are disclosed. The MEMS ESA antenna includes a MEMS E-plane steerable lens array and a MEMS H-plane steerable linear array. The MEMS E-plane steerable lens array includes first and second arrays of wide band radiating elements, and an array of MEMS E-plane phase shifter modules disposed between the first and second arrays of radiating elements. The MEMS H-plane steerable linear array includes a continuous transverse stub (CTS) feed array and an array of MEMS H-plane phase shifter modules at an input of the CTS feed array. The MEMS H-plane steerable linear array is disposed adjacent the first array of radiating elements of the MEMS E-plane steerable lens array for providing a planar wave front in the near field.

Abstract: A system and method for beamforming signals received in sparse, irregular sensor arrays has a network of sensors organized into sensor clusters, a signal processing node for each sensor cluster for beamforming the signals received by the sensors in each sensor cluster and an aggregation node for combining the beamformed responses from each sensor cluster to form a composite response characterized by minimized side lobes and grating lobes.

Abstract: A multiple-beam electronic scanning antenna including an array of phase-shifters (2, Dij). The N simultaneous beams are obtained in N directions by a law of excitation (fij) applied to each computed phase-shifter (Dij) by summing the phase laws &psgr;1, &psgr;2, . . . &psgr;k, . . . &psgr;N associated respectively with each 1, 2, . . . k, . . . N order direction and by applying the resultant phase-shift (&psgr;tij) to the phase-shifter, without applying the resultant amplitude modulation (&rgr;ij). The multiple-beam electronic scanning antenna especially is applicable to uniquely phase-controlled antennas in satellite or terrestrial communications requiring simultaneous communications with several variable sites.

Abstract: A switch (10) having a beam-forming network (12) generates independently steerable beams (26). One or more of the independently steerable beams couple in radiating communication with selected ones of M beam ports (18). A feeder array (11) or second beam-former (13) provides signals to radiating elements 19 to form multiple antenna beams for communication.

Abstract: A scanning array antenna (300) produces a directional beam by differentially rotating two, co-axial, flat phasing plate assemblies (302, 304). Each plate (302, 304) consists of a phase shifting means designed to efficiently pass incident radio frequency (RF) energy while imparting a particular phase shift to the energy. The energy can be supplied by a feedhorn (406) located behind the plates (402, 404) or can be introduced above the plates (508) and reflected by a ground plane (506) on the bottom plate (504). A method for producing the directional beam using the scanning array antenna (300) determines (804) the desired beam direction, calculates (806) the appropriate plate rotation angles (326, 328), and rotates (808) the plates (302, 304) at the appropriate time.

Abstract: A method and device for aligning a satellite receiver antenna with a broadcast satellite is disclosed herein. The device includes a receiver for measuring a signal strength from the satellite and issuing commands based on the measurement, a receiver antenna capable of automatically changing its alignment, and a rough alignment indicator located remotely from the receiver for signalling when the antenna is pointed sufficiently toward the satellite allow the receiver to maximize the signal strength by aligning the antenna with the satellite via commands from the receiver. The method includes placing the receiver antenna on a stable surface, manually pointing the antenna in the direction of the satellite until an indicator signals that the antenna is preliminarily aligned, fixing the receiver antenna to the stable surface, and activating a device remote from the antenna to automatically perform final alignment of the antenna with the satellite.

Abstract: The invention provides a multibeam antenna comprising:an array 11 of N.sub.e elementary sources 31; energy-focusing optical means comprising a reflector 10 or a lens; the array being situated in the focal zone of said focusing means: and a feed and control circuit cooperating with the N.sub.e primary sources 31 to produce N.sub.b beams each generated from a subgroup of the primary sources, some of which are shared between overlapping beams; the feed and control circuit comprising phase shifter means and attenuator means, said means being organized in N.sub.e feed channels for said N.sub.e primary sources, each feed channel including specific means for acting on the phase and the amplitude of an excitation signal in each feed channel;wherein each required beam is generated by the multibeam antenna solely by acting on the phase and the amplitude of the excitation delivered to each elementary source forming a portion of said beam; andwherein the number of sources N.sub.i contributing to a beam i, 1.ltoreq.i.

Abstract: An optical heterodyne system provides the radiation source and beam scan control of a millimeter wave (MMW) array antenna. The heterodyne system is an optical feed system to produce the MMW by mixing the optical outputs from two lasers, distribute the signal source to an array of radiating elements through a Rotman lens and optical fibers, generate the differential phase shift for beam scan in the optical domain, change the beam direction by switching the input laser being used to illuminate the Rotman lens or by varying the frequency of one of the laser sources. The feed system includes a plurality n-1 lasers spaced along the transmit side of the lens, and a center laser disposed on the center axis of the transmit side. A l:n switch receives a command input to determine which of the n-1 lasers will operate. The beat frequency between the center laser operating frequency and that of the n-1 lasers is the MMW frequency.

Abstract: The system includes a base unit sensitive to infrared (IR) signals transmitted by a mobile remote unit to an IR receiver which is placed behind a rotating set of signal blocking blinders whose position at any time defines a view angle with a position known with precision resulting in the IR signal reception scanning across an area. The base unit detects when the peak strength of the signal occurs and utilizes this data to determine the exact effective angle between the axis of the IR signal and the base unit to create an error signal used by the base unit to position the camera mounted thereon. Receivers for TILT and two PAN positions, PAN 1 and PAN 2, are used to include range calculations for ZOOM functions. Command circuitry to override the automatic tracking function is provided in the base unit.

Abstract: A cellular communications satellite system is disclosed which comprises a plurality of ground-based base stations, mobile stations, and at least one orbiting satellite for relaying signals between the base stations and mobile stations. A Plurality of feederlinks are used between the base stations and the satellite for transmitting signals and power from the ground stations to the satellite.

Abstract: The invention pertains to an electronic sweep device with integrated active lens and light source.The device includes a bundling of superimposed channels C which are separated by thin metal planes P that include, in front of a metal short-circuit plane (10), illumination organs (S) and phase displacement organs (B).The invention makes it possible to create a compact electronic sweep device which eliminates the parasitic reflection phenomena between illuminator and lens for the purpose of controlling a hyperfrequency beam.

Abstract: Apparatus for calibrating a phased array antenna having a plurality of active modules and a test manifold. An RF antenna, which is both a transmitting and receiving antenna is positioned at a far field range from the antenna to be calibrated. A receiver is connected to the output of the far field receiving antenna and the output of the test manifold of the antenna to be calibrated for the transmit calibration and a transmitter is connected to the far field transmitting antenna and the test manifold for a receive calibration, a command phase and amplitude for each steering angle of each module of the antenna being calibrated. The phase and amplitude data from the test manifold is compared with the phase and amplitude data of the far field range to obtain an error signal, and the error signal is combined with the command amplitude and phase iteratively until the error signal is minimized for each module of the antenna.

Abstract: An active array antenna for use, for example, in a radar system, includes elemental antennas, each with a T/R module, distributed over a circular aperture. For lowest cost, the aperture is thinned. The T/R modules are operated at maximum output, to achieve maximum DC-to-RF efficiency, and for simplicity. A phase controller controls the phase shift which is imparted by each module to its signal, to form a main beam and its associated sidelobes. A perturbation phase generator portion of a phase controller adds a perturbation phase shift selected, in conjunction with a particular thinning distribution, to form a relatively wide null in the sidelobe structure, in which signal transduction is reduced. In a radar context, this null may be placed on a source of ground clutter or a jammer.

Abstract: This invention relates to a satellite signalling system. A ground station receives paging signals from an earth-bound terminal, and an up-link radio transmitter/antenna transmits paging signals and control signals to a satellite in earth orbit. An up-link receiver coupled to the satellite receives the paging and control signals. A down-link transmitter is coupled to an antenna whose beam may be directed in a predetermined sequence to a plurality of locations on earth as paging signals are transmitted to earth.