Abstract: The present invention provides an open-loop method for determining uplink transmission power in a satellite communication system 200 that compensates for antenna pointing error attenuation and for rain attenuation. Satellite downlink signal 208 attenuation is measured. Antenna pointing information is then used in conjunction with antenna gain pattern information 400 to determine antenna pointing error attenuation. The measured downlink attenuation and antenna pointing error attenuation are then used to determine the amount of rain attenuation on the downlink 208. The downlink attenuation information is then used to determine the amount of uplink 216 attenuation to be expected. Uplink transmission power levels are then adjusted accordingly to overcome the expected uplink 216 attenuation.

Abstract: An antenna control system is connected to an antenna in order to control the position of the antenna. The system includes a motor connected to the antenna for adjusting the position or vertical tilt angle of the antenna. A driver is provided for operating the motor. A sensor is also provided to detect the position of the antenna. In addition, an antenna controller is connected to an antenna memory, the driver, and the sensor, for reading the detected position of the antenna and for controlling the driver to adjust the antenna's position. A main controller is connected to the antenna controller for sending commands to and reading data from the antenna controller. In this manner, the main controller can interface with any number of antennas at a base station and control the position or down-tilt of each antenna. According to one embodiment of the control system, a user interface is also provided for entering commands to and reading data from the main controller.

Abstract: A sectorized smart antenna system includes multiple sector antennas with a software control algorithm for flexible association of physical antennas to a logical serving sector to provide signal coverage in a particular region of the cell served by the base station. The control algorithm can adapt to different situations without requiring any, or only very limited, physical hardware changes to reconfigure a base station to balance the traffic load throughout the cell. The smart antenna system and method includes measuring and recording a mobile station's signal strengths and its rate of changes received by an antenna in a serving sector relative to other antennas in either the same serving sector or different serving sector to determine the mobile station location and its movement, determining when a threshold signal level is reached, and handing-off the mobile station to an adjacent antenna, serving sector, or cell.

Abstract: A system and method for statistically modeling the operation of a directional terminal antenna in a wireless link. When using a directional terminal antenna, received power may be enhanced by as much as the antenna gain. In local scattering, however, the enhancement will be smaller. The system and method model this decrement, known as the gain reduction factor, &Dgr;, for fixed suburban paths, based on angle-of-arrival measurements. The system and method also provide the capability to statistically model the transmission performance of a directional terminal antenna in a wireless link while analyzing influences of antenna height, antenna beamwidth, distance and season.

Abstract: An antenna for cellular telephone communications systems, particularly intended for base stations (RPF) of DECT standards, which is able to search for the best path to the user, is formed as a multimode, adaptive, dual antenna, apt to take up both a narrow lobe configuration, with variable orientation on a horizontal plane, and an omnidirectional configuration on a horizontal half-plane, the two antennas composing said dual antenna being similar, integrated onto the same dielectric substrate, and working simultaneously with two different roles (traffic support; search for optimal orientation), said roles being exchanged at every receipt-transmission cycle.

Abstract: An antenna driving device for a mobile communication terminal including a flat antenna and a receiver for receiving a radio signal through the flat antenna. The device has a flat antenna driver for shifting the direction of the flat antenna by predetermined steps; an RSSI detector for detecting the RSSI value of the received radio signal for each shifting step of the flat antenna; a position detector for detecting a position of the flat antenna through the flat antenna driver; a memory for storing the RSSI value detected for each step and the associated flat antenna positional information; and a controller for controlling the flat antenna driver and the RSSI detector, and for shifting the direction of the flat antenna to a position having the highest RSSI value by controlling the flat antenna driver. The flat antenna driver comprises a motor for shifting the direction of the flat antenna; and a driver for driving the motor under the control of the controller to shift the direction of the flat antenna.

Abstract: The satellite selection method as utilized by the spaceborne Global Positioning System receiver provides navigational solutions and is designed for use in low Earth orbit. The satellite selection method is a robust algorithm that can be used a GPS receiver to select appropriate GPS satellites for use in calculating point solutions or attitude solutions. The method is takes into account the difficulty of finding a particular GPS satellite phase code, especially when the search range in greatly increased due to Doppler shifts introduced into the carrier frequency. The method starts with an update of the antenna pointing and spacecraft vectors to determine the antenna backplane direction. Next, the GPS satellites that will potentially be in view of the antenna are ranked on a list, whereby the list is generated based on the estimated attitude and position of each GPS satellite. Satellites blocked by the Earth are not entered on this list.

Abstract: A method and apparatus for aiming a satellite antenna at a target satellite allow a user to enter a commonly known geographic designator, such as a ZIP Code. From the ZIP Code the longitude and latitude of the antenna is determined. The user also inputs the longitude of the target satellite or the name of the satellite, from which the longitude is looked-up. The system also references a model of variation in Earth's magnetic field so as to determine the variance at the antenna's location and correct the aiming parameters for that variance.

Abstract: In order to control the direction of a beam antenna, at least one magnetic sensor is attached to the antenna for measuring at least one of the horizontal and vertical components of the geomagnetic field. A magnetic sensor circuit converts the output of the magnetic sensor into an electric signal which varies corresponding to changes in the measured geomagnetic field according to the direction of the antenna. A processor determines the current direction of the antenna based on an output of the magnetic sensor circuit and outputs a control signal for setting the antenna in a desired direction. A motor rotates the antenna, and a power source drives the motor. A control unit receptive of a motor control signal output by the processor controls the rotation of the antenna.

Abstract: An antenna control system is connected to an antenna in order to control the position of the antenna. The system includes a motor connected to the antenna for adjusting the position or vertical tilt angle of the antenna. A driver is provided for operating the motor. A sensor is also provided to detect the position of the antenna. In addition, an antenna controller is connected to an antenna memory, the driver, and the sensor, for reading the detected position of the antenna and for controlling the driver to adjust the antenna's position. A main controller is connected to the antenna controller for sending commands to and reading data from the antenna controller. In this manner, the main controller can interface with any number of antennas at a base station and control the position or down-tilt of each antenna. According to one embodiment of the control system, a user interface is also provided for entering commands to and reading data from the main controller.

Abstract: The system includes a path planning system adapted to store a site model of the field. The site model includes data defining a plurality of parameters associated with the field. The path planning system is further adapted to receive information indicative of a work implement connected to the agricultural machine, and a desired work operation of the agricultural machine. A plurality of desired paths for the agricultural machine to traverse are planned as a function of the plurality of field parameters, the work implement, and the desired work operation. An autoguidance control system is adapted to receive the plurality of desired paths, and responsively produce a control signal upon activation of the autoguidance control system. A machine control system receives the control signal, and responsively controls the operation of the agricultural machine with respect to the plurality of desired paths.

Abstract: A smart antenna system includes: an antenna array including a plurality of antenna elements, and at least one calibration element; a plurality of transceiver units each having a port coupled with an associated one of the antenna elements, a receive port, and a transmit port; a transceiver calibration unit including a port coupled with the calibration element via a coaxial cable, a receive port, and a transmit port; and signal processing means communicatively coupled with each of the receive ports and the transmit ports of each of the transceiver units, and coupled with the calibration receive port and the calibration transmit port of the calibration unit. A transmitter calibration path associated with each antenna element extends from the transmit port of the associated transceiver unit to the associated antenna element, from the associated antenna element to the calibration element, and from the calibration element to the receive port of the calibration unit.

Abstract: A system and method for eliminating pointing error in a beacon tracking system due to uncontrolled differences in passive loss or in amplification of the separate signals involved in creating a pilot signal. A locally generated reference signal (30) is radiated onto a set of feed horns (14), at least three (20, 22, 24) of which are used to track a pilot signal (18). The reference signal (30) is detected and used in an automatic gain control feedback loop (44, 46, 48) to maintain equal gain on the separate feed horn channels. The equalized signal is processed (62) to produce precision tracking signals.

Abstract: A system and method for aligning an antenna. Signals broadcasted over a number of channels for each of a plurality of orientations of the antenna may be received. From such received signals, information pertaining to at least one of (i) an error rate, (ii) a signal level, (iii) equalizer tap coefficients, and (iv) error correction for each orientation of the antenna for each channel is obtained and used to determine an acceptable orientation for the antenna for each channel.

Abstract: An antenna assembly for forming and directing a transmit beam, and for controlling receive and transmit beam tracking of a spacecraft in the presence of planetary aberration. The assembly includes a main reflector, a sub-reflector centered along an optical axis of the main reflector, and a moveable transmit feed for directing electromagnetic radiation along a longitudinal axis thereof. The assembly also includes an intermediate beam waveguide assembly arranged between the moveable transmit feed and the main reflector, wherein the intermediate beam waveguide assembly includes fixed and moveable optical components for guiding electromagnetic beam energy between the moveable transmit feed and the main reflector. A beam steering mechanism is coupled with the moveable transmit feed for angularly displacing the transmit beam from the optical axis by displacing the moveable transmit feed in a direction substantially orthogonal to the longitudinal axis of the transmit feed.

Abstract: An antenna for receiving a satellite broadcast can adjust orientation at higher precision than a method based on a compass and a level, without being influenced by environmental magnetic field generated by magnetic body or electromagnetic sources, can perform adjustment of orientation even before a radio wave from the satellite is not catched, can monitor the deviation during the fixation of the antenna orientation to improve the workability in adjustment of antenna orientation. The antenna for receiving a satellite broadcast has a reflector for reflecting a radio wave from a satellite on a reflecting surface for convergence and a receiving portion for receiving the radio wave reflected by the reflector. The antenna further includes a light blocking portion forming a shadow by the sun light, a scale determining a direction of the sun by the shadow formed by the light blocking portion. The light blocking portion and the scale are provided at an upper end portion of the reflector.

Abstract: A method and apparatus for training a receiver on a source are provided. The receiver is an antenna and the source is a broadcast satellite. A first signal sensor receives at least one signal from the source. The first signal sensor may be a first low noise block (LNB) downconverter of the antenna. At least one secondary signal sensor measures a strength of the received signal. The secondary signal sensor comprises four LNB downconverters, wherein each of the four LNB downconverters are located on each of four sides of the first signal sensor. The measured strength of the received signal is used to provide guidance information for training the receiver on the source. When the broadcast satellite moves relative to the antenna, the secondary LNB downconverters detect a variance in the measured strength of the at least one signal and provide guidance information based on the detected variance, thereby reducing the training time for the antenna.

Abstract: A vehicle positioning and data integrating process and system can substantially solve the problems encountered in avionics system integration, which employs integrated global positioning system/inertial measurement unit enhanced with altitude measurements to derive vehicle position, velocity, attitude, and body acceleration and rotation information. A vehicle positioning and data integrating system comprises navigation sensors and an IMU interface and preprocessing board, an altitude interface and processing board, a navigation processing board, a shared memory card, a bus arbiter, a control board, and a bus interface. The control board distributes navigation data to flight management system, flight control system, automatic dependent aurveillance, cockpit display, enhanced ground proximity warning system, weather radar, and satellite communication system.

Abstract: A radio wave receiving apparatus including a signal processing circuit which performs on Fourier transform with respect to an azimuth of an electric field signal outputted from an antenna receiving circuit. The Fourier transform is also performed with respect to an azimuth of the antenna pattern of an antenna. The Fourier transform signal derived from the electric field signal is then divided by the antenna pattern Fourier transform signal. A low-pass filter subjects the divided signal to low-pass filtering. The band of the output signal of the low-pass filter is extended into that beyond the cut-off frequency of the low-pass filter by using extrapolation. The band-extended signal is subjected to Fourier inverse transform with respect to azimuth, the signal after the Fourier inverse transform being outputted as a final antenna output.

Abstract: A computer software program simulates a communication network using network characteristic information provided by communication network designers. When a network designer selects a particular location within the network, the software consults the network characteristic information to predict a signal attribute of a simulated signal received at the selected location. The predicted attribute is used to modify a template signal to produce a simulated output signal, and the simulated output signal is presented for consideration by the network designers.

Abstract: A communication system has a primary radio station and a portable radio station. The primary radio station communicates with the portable radio station. The portable radio station is freely three-dimensionally orientable with respect to a fixed coordinate system. The portable radio station has a transceiver, a controllable antenna structure, and a beam directional controller for three-dimensionally controlling a beam radiated by the controllable antenna structure. The portable radio station further has a three-dimensional geometric sensor for three-dimensionally sensing a local magnetic field. The beam is controlled on the basis of the sensed local magnetic field.

Abstract: The present invention relates to a satellite tracking apparatus and control method for performing attitude control of a vehicle-mounted antenna for receiving a satellite broadcasting and operating the antenna. The present invention employs a hybrid tracking method that performs tracking using an electronic beam in an elevation direction while performing mechanical tracking in an azimuth direction. The electronic tracking is employed in controlling the azimuth direction to compensate for a tracking error in the azimuth direction. While the tracking performance of the present invention is similar to that of the full-electronic antenna, the present invention achieves better beam efficiency by arranging radiating elements to be effective in front of the antenna, thereby realizing a high gain antenna.

Abstract: In a mobile communication system, each base station is provided with an array antenna, a section for estimating the respective directions of one or more mobile stations with which the base station is in communication, based on estimated incoming directions of radio waves received from these mobile stations, and sections for operating on respective signals of the antenna elements constituting the array antenna such as to shape the radiation pattern of the antenna to form peaks of directivity which are oriented in the estimated directions of these mobile stations, and can include a capability for shaping these peaks in accordance with estimated positions of these mobile stations, thereby minimizing interference between transmissions from that base station and communication being executed between other adjacent stations of the system, and minimizing the number of different transmission frequencies required in the overall system.

Abstract: An RF beam pointing apparatus (500, 600) compensates for the effects of settling errors on antenna pointing. The beam pointing apparatus includes an attitude reference system (502, 528, 530, 534) generating an antenna attitude output from the satellite attitude. Also included is attitude comparison circuitry (528, 530), coupled to the attitude reference system, that includes an antenna pointing error output. Control circuitry (528, 530) is coupled to the attitude reference system (502, 528, 530, 534) and the attitude comparison circuitry (528, 530). The control circuitry (528,530) directs the attitude comparison circuitry (528, 530) to generate control error output signals in response to dynamic settling antenna pointing errors induced by a mechanical slew on the satellite.

Abstract: A self-structuring antenna system that includes an antenna array defined by a plurality of antenna elements that are selectively electrically connectable to each other by series of switches, so as to alter the physical shape of the antenna array. The antenna elements include antenna wires, where the wires of adjacent antenna elements are connected by a mechanical or solid state switch. One or more feed points are electrically connected to predetermined locations within the antenna array and to a receiver associated with the antenna array. A feedback signal from the receiver provides an indication of signal reception and antenna performance. The feedback signal is applied to a computer that selectively opens and closes the switches. An algorithm is used to program the computer so that the opening and closing of the switches attempts to achieve antenna optimization and performance.

Abstract: The present invention provides a method for determining antenna pointing error of a satellite antenna (702-716) that produces at least one spot beam having a corresponding gain pattern. The method obtains from a first unique location (510) on the ground a first measurement of a spot beam strength for a first cell (502). Similar measurements are obtained at second and third unique locations (512, 514). Attitude component errors, for example the roll or pitch attitude component errors may then be determined. The method may further determine a yaw attitude component error based on fourth, fifth, and sixth measurements of spot beam strength made from unique locations (616-620) in a second cell (604) also generated by the antenna. Additional measurements may be collected in each beam at unique locations (510-514, 516-520, 610-614, 616-620) and averaged to reduce the temporary or zero means effects of rain, scintillation, or other atmospheric conditions on the spot beam strength.

Abstract: In order to carry out the on-site determining of the error of orientational adjustment of an electronic scanning antenna, this error being due to defects of manufacture of the radiating face of this antenna, radioelectric measurements are used during the qualification of this antenna. These measurements are made for several directions of the antenna beam, and the most likely components of the aiming error are selected.

Abstract: A system for acquiring the beacon of a satellite and synchronizing data transmission between the satellite and a ground terminal is disclosed. The ground terminal conducts a search for a satellite to be acquired. The search may be based on previously developed information from which the location of the satellite can be predicted and, thus, limited to a small area of the sky, or cover a large area of the sky in accordance with a search routine. After the beacon of a satellite is acquired, the geographic area served by the satellite is determined. If the satellite does not serve the cell within which the ground terminal is located, a further satellite search is conducted, which may be based in part on information contained in the beacon of the acquired satellite. After the satellite serving the cell containing the ground terminal is acquired, a test is made to determine how long the satellite will continue to cover the cell.

Abstract: A hybrid system for stabilizing the attitude of an instrument relative to a dynamic platform includes a plurality of (roll, pitch and yaw) inertial rate sensors, whose outputs are sampled at a rate sufficient to provide real time tracking of changes in orientation of the platform, and a global positioning system (GPS) receiver, whose precision platform attitude output is updated periodically, but at a rate less than the rate of change of attitude of the platform. The inertial rate sensors provide effectively continuous motion (e.g., angular rate) data signals representative of three-dimensional changes in attitude (position derivative signals) of the platform. The inertial rate output are integrated to provide output signals representative of the dynamic orientation of the platform. Sequential outputs of the integration-processing circuitry are also coupled to a sample buffer, which is controllably read-out in accordance with the periodic updates from the GPS receiver.

Abstract: A user terminal (110) includes a rotating electronically steerable antenna system (210) which combines coarse mechanical beam steering with fine electronic beam steering to provide full hemispherical coverage and enable hand-offs in a satellite communication system. The antenna system (210) comprises at least one antenna unit (and preferably two antenna units) including a mechanically rotatable base (330), an antenna holder (320) coupled to the mechanically rotatable base, and two electronically steerable antenna subunit (310) mounted on the antenna holder. Antenna system (210) also includes an antenna unit controller (260) adapted to control rotation of the mechanically rotatable base (330).

Abstract: In a cellular telecommunications network, uplink interference, as measured by a base station in a target cell, and co-channel interference, as measured by mobile units in a co-channel cell are reduced by increasing the base station antenna tilt angle. However, increasing the base station antenna tilt angle reduces the effective coverage area of the target cell. To obtain an optimum base station antenna tilt angle, interference reduction and target cell coverage area reduction are quantified for each of a number of candidate base station antenna tilt angles. An interference reduction-to-target cell coverage area reduction ratio can then be established for each of the candidate base station antenna tilt angles. The optimum base station antenna tilt angle can then be identified as the one candidate base station antenna tilt angle that reflects the maximum interference reduction-to-target cell coverage area reduction ratio.

Abstract: An SHF-band receiving apparatus is used for demodulating a signal received by an antenna and input through a cable by using an indoor receiving unit which comprises; demodulation means for demodulating an input signal supplied thereto through the cable; detection means for detecting a detection signal representing the direction of the antenna from a demodulated signal output by the demodulation means; and output means for generating a modulated signal for displaying information on the direction of the antenna by modulation of a carrier signal based on the detection signal produced by the detection means and for outputting the modulated signal through the cable to the antenna side.

Abstract: A tracking system for maintaining an alignment between a reflector antenna and a source of electromagnetic radiation, includes a reflector for reflecting electromagnetic radiation generated from a electromagnetic radiation source, a receiver, and a rotary sub-reflector which is positioned in front of the reflector for deflecting the radiation reflected by the reflector to the receiver and for generating triggering signals for measuring the strength of signals of the reflected radiation, whereby the sub-reflector is arranged at an inclination with respect to the reflector by an offset angle.

Abstract: A method and apparatus for efficiently tracking satellites includes a geosynchronous satellite (10) for transmitting the ephemeris of non-geosynchronous satellites (20, 30) to a ground terminal (50). The ephemeris is computed by the non-geosynchronous satellites (20, 30) or by other means such as a ground station (60). A ground terminal (50) can quickly acquire a non-geosynchronous satellite (20, 30) by receiving fresh ephemeris data from a geosynchronous satellite (10), determining a location of a non-geosynchronous satellite (20, 30), and orienting an antenna.

Abstract: An antenna controller mounted on a movable body is provided for controlling antenna driving for satellite tracking. The antenna controller comprises a step tracking circuit for performing step tracking operation on a turning face of the movable body while receiving electromagnetic waves from a satellite, and for calculating an antenna pointing direction in which an intensity of the electric wave is strongest. An antenna driving circuit drives the antenna in the antenna pointing direction, while a reference output correcting circuit adds a correction quantity to a reference output of a rate sensor based on a result of the step tracking operation.

Abstract: A satellite capturing/tracking apparatus including: an antenna drive unit for driving an antenna in such a manner that said antenna is directed to a direction along which electromagnetic waves are transmitted from either a data relay satellite or a space station in response to a capturing/tracking command; an orbit/position detecting unit for receiving clock signals transmitted from a plurality of GPS satellites to calculate and output the present orbit and position of said apparatus as orbit/position information; a first storage unit for previously storing therein a capturing/tracking sequence program with relative time instants, produced by an azimuth angle and an elevation angle of either said data relay satellite or said space station; a second storage unit for storing therein data used to define a relationship between said azimuth angle, said elevation angle, and the orbit/position of said apparatus with respect to either said data relay satellite or said space station; and a capturing/tracking control u

Abstract: A vehicle-mounted satellite signal receiving system adopting a satellite tracking system combining gyro tracking and hybrid tracking is disclosed which can correct a sensitivity coefficient for correcting a gyro sensor output signal to make up for a sensitivity error, even when a drift is produced in the sensitivity error. In this system, gyro tracking is caused when the received power level is above a threshold power level. The gyro tracking is done by determining the angular velocity .omega. of an antenna as .omega.=-(.omega.G.times..DELTA.SB+.omega.G from a value obtained by inverting the sign of the product of a gyro tracking angular velocity .omega.G and a sensitivity coefficient .DELTA.SB for dealing with the sensitivity error and a predetermined offset error correction value .omega.G and setting the antenna to .omega.. When .DELTA.SB is inaccurate and a sensitivity error is generated in the gyro sensor output signal, the received power level is reduced.

Abstract: An satellite antenna aiming device for continuous real time adjustment of the elevation and direction of a satellite antenna to receive the optimum signal to and from a desired satellite. The Device features motor driven gears for horizontal and vertical adjustment of the antenna to the proper desired elevation and direction. The aim of the antenna is controlled by an on board computer programmed to use information from one or all of a number of position communicating devices including an accelerometer, a keypad for entering pre determined position codes, an magnetometer, or a global positioning locator or GPS device. Software containing logarithms using information from the positioning devices calculate the optimum elevation and direction for the antenna to communicate with the satellite and activate the motors to adjust the satellite.

Abstract: An inexpensive high gain antenna for use on terminals communicating with low earth orbit (LEO) satellites which include an elevation table mounted for arcuate movement about a transverse axis on an azimuth turntable mounted for rotational movement about a central axis. A plurality of antenna elements forming a phased array antenna are mounted on the top of the elevation table and have a scan plane which is parallel to and extends through the transverse axis of the elevation table. The antenna may be both mechanically and electrically scanned and is used to perform handoffs from one LEO satellite to another by positioning the elevation table of the antenna with its boresight in a direction intermediate the two satellites and with the scan plane of the antenna passing through both satellites. At the moment of of handoff, the antenna beam is electronically scanned from one satellite to another without any loss in data communication during the process.

Abstract: An Earth station having an antenna is configured to establish communication with a satellite. The Earth station stores a table of satellite position data for a plurality of satellites and is configurable to enable its own location position on the surface of the Earth as well as the azimuth and elevation of its antenna to be obtained. The tabulated satellite position data is then utilised to calculate the position of the satellite in relation to the location position. Thereafter at least one of the satellites is selected with which to establish communication and in response to the selection and the obtained azimuth and elevation, a direction is determined in which to configure the antenna for operation with the at least one selected satellite. Following determination of the direction, the antenna is configured for operation with the at least one selected satellite. The location position and the azimuth and elevation of the antenna may be determined through the Earth station comprising a GPS receiver.

Abstract: An avionics display (10) for use in an aircraft navigation system including a navigation receiver. The avionics display (10) includes a needle (12) for indicating the position, heading, glide slope or other navigational parameter of the aircraft and a stepper motor (14) coupled with the needle and responsive to the navigation receiver for driving the needle in response to the navigation signals received by the receiver. The stepper motor drives the needle at a much higher torque than prior art displays and is therefore less sensitive to contaminates and magnetic interference and is less fragile.

Abstract: A regional attribute for a region in which a vehicle is traveling is detected by a vehicle navigation device, and vehicle drive force characteristics such as a throttle gain of an electronic throttle or a speed change pattern of an automatic transmission are modified according to the regional attribute. An operation amount of an accelerator operated by a driver is detected, and by not modifying the drive force characteristics when the accelerator operation amount is not zero, abrupt change of drive force is avoided, and the sense of discomfort experienced by a driver due to abrupt change of drive force is eliminated.

Abstract: An antenna aiming method and apparatus for automatically pointing an antenna to a selected distant location. The antenna aiming apparatus includes a database for storing data for distant locations, an electronic compass for determining a reference azimuth for the local antenna, and a global positioning system (GPS) receiver for determining a local location. A processor computes a pointing direction having an azimuth and an elevation from the local location to the distant location and then computes a horizontal rotation angle between the pointing direction and the reference azimuth and a vertical rotation angle from horizontal to the elevation. An antenna rotator servo-mechanism under processor control rotates the local antenna by the horizontal and vertical rotation angles for pointing the local antenna to the distant location.

Abstract: A method and apparatus for adjusting the position of an antenna to improve reception at a television includes a signal generator which measures the signal strength received by the antenna. The signal generator sends a low frequency coded signal to a display visible to a person who is adjusting the antenna. The display provides a quantitative indication of the signal strength to the installer of the antenna, allowing precise adjustments to be made in accordance with the displayed value. The signal generator provides the coded signal to the display via the same cable used to carry the received signals from the antenna to a receiver, such as a set-top box.

Abstract: A beam steering control for a mobile satellite communications antenna, includes an antenna having a steering mechanism; a dynamic rate sensor for producing a signal related to the rate of change of position of a vehicle to which the antenna is mounted; and a control system for controlling the steering mechanism, the control system including a satellite tracking loop, an inertial stabilization loop, a calibration algorithm for dynamically calibrating the rate sensor, and a satellite acquisition algorithm for determining a azimuth angle of the antenna relative to an inertial reference.

Abstract: A satellite communication method enables a low earth orbit data collecting mission satellite to conveniently achieve continuous, real time, and cost effective global connectivity by "plugging in" to a constellation of low earth orbit communication satellites designed to provide mobile satellite service for terrestrial users. Orbit parameters for the mission satellite are selected to generate a nodal regression rate matched to that of the communication satellites so that initial alignment of orbit planes is sustained maintaining a favorable geometry between the communicating satellites. The resulting intra-satellite geometry is exploited through use of widebeam crosslink antennas, simplified pointing techniques, and variable transmission rates for optimum communication efficiency from the mission satellites to communication satellites and ground receivers.

Abstract: A computer vision system is disclosed that utilizes a spinning array of podetectors. The array is rotated about the focal plane of a lens and scans all the possible orientations and positions of the edges of the unknown object. In one embodiment, the photodetectors are elongated so as to provide for maximum light gathering ability along the direction of elongation and a minimum light gathering ability in the direction perpendicular to the direction of elongation. In other embodiments, optical means are used to focus the image onto conventional photodetectors while still having the ability to more efficiently determine edge segments of unknown objects. The system efficiently and rapidly implements the wavelet projection transform to characterize-multi-scale edge segment features of an image of an unknown object. An imaging radar system that utilizes a spinning antenna system having frequency scanning provisions is also disclosed.

Abstract: The disclosure describes a moving receiver station capable of receiving broadcast entertainment signals from a first geostationary satellite associated with a first program provider, or from a second geostationary satellite associated with a second program provider. The receiver station is part of an aircraft and includes a tracking antenna and switching and control system that locks the tracking antenna on either the first or second satellite. The switching and control system receives position information, program attribute information and satellite coverage area information to determine when the aircraft is leaving one coverage area and entering another. The switching and control system switches the antenna to the second satellite when the aircraft enters the second coverage area, and limits the availability of received programming based on whether the aircraft is leaving the first coverage area or entering the second coverage area.

Abstract: A garage door opener transmitter system includes a sensor for determining the relative direction of the garage door opener receiver. A transmitter then selectively transmits a signal in the direction of the receiver. In one embodiment, the direction of the receiver is determined based upon a compass and the direction of travel of the vehicle at the time the signal is transmitted.

Abstract: A video apparatus for receiving broadcast direct-to-home audiovisual program data is provided with a position generator disposed at a position which generates a position signal corresponding to the position, an antenna for receiving broadcast audiovisual program data, the antenna being positionable in a plurality of different orientations including an initial orientation, a decoder coupled to the antenna for decoding the program data and being adapted to be connected to e.g. a home video display for display of programming corresponding to the program data, and an adjustment mechanism coupled to the antenna for automatically adjusting the initial orientation of the antenna based upon the position signal generated by the position generator. The antenna may be, for example, a satellite dish that is adapted to receive broadcast carriers from a broadcasting satellite. The adjustment mechanism may automatically orient the antenna based upon the relative qualities (e.g.