Abstract: A method and apparatus for reducing electromagnetic interference (EMI) and jamming in Global Positioning System (GPS) receivers operating on rolling or spinning platforms and/or environments is provided. An antenna system having a pair of diametrically-mounted elements provides interferometric cancellation for spatial and polarization nulling of interference signals. The antenna system, operating in conjunction with multiplexing and anti-jamming electronics, provides interference suppression for a GPS receiver connected thereto. Interference cancellation is provided in jamming and non-jamming environments by selectively employing spatial or polarization nulling of the interference signal.

Abstract: A scheme for selecting two beams in a switched beam antenna system for providing downlink communications in a downlink channel, the switched beam antenna system providing uplink reception and downlink transmission is described. The scheme involves selecting a pair of beams based on the uplink reception of the switched beam antenna system, and determining from the pair of beams a corresponding pair of orthogonal beams. The scheme also involves providing the pair of orthogonal beams as a pair of transmit beams for the downlink transmission of the switched beam antenna system.

Abstract: A container (10) (or other returnable item) for the storage and delivery of goods, comprises antenna means (16) for radio frequency use, and connection means (18) for receiving a removable drive circuit means (20). The drive circuit (20) is operable to communicate by means of the antenna (16) when connected therewith. The connections (18) serve, in use, to connect an installed drive circuit (20) with the antenna (16) to allow the drive circuit (20) to communicate. This allows the identity of the container or its contents to be communicated to a remote location.

Abstract: An antenna system is disclosed including a GPS antenna which is driven by an articulator in an opposite direction to aircraft roll. Aircraft roll is sensed by an onboard navigation system and translation module sends a signal to a processor which provides a drive signal to the articulator. As the aircraft rolls in one direction, the antenna is driven oppositely to maintain the vertical orientation of the antenna.

Abstract: A portable, remote-controlled or automated robotic (capable of operating in an unmanned mode) transceiver using a directional antenna pointing system The system comprises a highly integrated, wireless, self-contained transceiver with robotic antenna pointing and an interface system for satellite, conventional antenna, and radar applications for personal, commercial, and military use.

Abstract: Methods and structures are provided for reducing pointing errors &zgr; of satellite antennas and for generating broad field-of-view satellite attitude acquisition patterns. In one method embodiment, satellite transmit beams have estimated pointing attitudes &bgr; and are transmitted to overlap on a ground-based receiving terminal which has a known terminal location &lgr; and which measures received signal strengths &agr;. Pointing errors &zgr; of the transmit beams are then determined from the estimated pointing attitudes &bgr;, the terminal location &lgr; and the signal strengths &agr; and the pointing errors &zgr; are subsequently reduced by revising the pointing attitudes &bgr;. Other method embodiments utilize known signal-strength functions and antenna signals with known signal parameters such as frequencies and/or modulations.

Abstract: Embodiments of the present invention are directed to a method and an apparatus for preventing interference of geosynchronous satellites due to ground stations with misaligned antennas. In one embodiment, a two-way satellite ground terminal is configured to communicate with a geosynchronous target satellite which transmits a target satellite signal. The ground terminal comprises an antenna which is configured to receive the target satellite signal from the geosynchronous target satellite only if the antenna is oriented toward the geosynchronous target satellite. A transmitter is configured to transmit signals from the ground terminal via the antenna A signal detector is operatively coupled with the antenna and with the transmitter.

Abstract: The present invention relates to a system for tilting polarization and steering main beam of airship antenna comprises: a 1st GPS receiver, which is located in the airship; a 2nd GPS receiver, which is located in the ground station; an airship antenna database for extracting the radiation pattern information of airship antenna and polarization information according to the posture of the antenna based on the position information of the airship; a ground station antenna database for extracting the radiation pattern information of ground station antenna and polarization information according to the posture of the antenna based on the position information of the ground station; a polarization and main beam direction correction operating device for computing the correction value of polarization and main beam direction of the airship antenna and the ground station antenna based on the position information of the airship and the ground station received from the 1st GPS receiver and the 2nd GPS receiver; and an airsh

Abstract: A hybrid optical and millimeter wave beam acquisition and tracking system and method. A host platform includes an INS and a GPS for generating geolocation data, optical and RF receivers, and a common optical/RF aperture. An interface is coupled to the host platform by way of a mechanical gimbal and includes a beamsplitter, an optical gimbal and optical aperture, and an RF aperture. A CPU on the interface includes an optical track error processor for acquiring the optical beam by systematically searching for a focused light spot in a focal plane of the optical receiver, an RF track error processor for outputting gimbal angles of the mechanical gimbal that are derived from the aperture of the RF receiver that are referenced to the inertial navigation system, and a search and track processor that generates an optical gimbal control signal for the optical gimbal and a mechanical gimbal control signal for the mechanical gimbal for tracking the optical and RF beams.

Abstract: A distributed antenna array comprising a plurality of antenna elements, and a plurality of power amplifiers, each power amplifier being operatively coupled with one of said antenna elements and mounted closely adjacent to the associated antenna element, such that no appreciable power loss occurs between the power amplifier and the associated antenna element, each said power amplifier comprising a relatively low power, linear power amplifier.

Abstract: Methods for aligning a satellite reflector with an antenna that has a feed/LNBF assembly. The feed/LNBF assembly is electronically coupled to a set top box which is electronically coupled to a television that has a television speaker. A transmitter is placed adjacent the television speaker. The speaker transmits the audio tones emitted by the television speaker which are indicative to the alignment of the antenna with a satellite to a speaker located adjacent to or attached to the antenna.

Abstract: Methods for aligning a satellite reflector with an antenna that has a feed/LNBF assembly. The feed/LNBF assembly is electronically coupled to a set top box which is electronically coupled to a television that has a television speaker. A transmitter is placed adjacent the television speaker. The speaker transmits the audio tones emitted by the television speaker which are indicative to the alignment of the antenna with a satellite to a speaker located adjacent to or attached to the antenna or antenna support structures.

Abstract: A communication system for communicating with a portable radio telephone is disclosed. The system comprises a transceiver, an antenna capable of directing a beam in a given angular direction, a database for storing information relating a location of the portable radio telephone to an angular beam direction, and a controller for configuring the antenna for communication with the portable radio telephone by directing a beam in the angular direction indicated in the database.

Abstract: A radio system includes a base station and a remote station. The base station includes a space-time encoder, an antenna system, a transmitter, a base station receiver, and a power management controller. The space-time encoder encodes a stream of symbols into first and second space-time coded signals, and the transmitter transmits the first and second space-time coded signals at respective first and second initial transmit powers from the antenna system so as to form respective first and second radiation patterns. The base station receiver receives power coefficient indicator information from the remote station, and the power management controller determines first and second adjusted transmit powers based on the respective first and second initial transmit powers and the power coefficient indicator information. In an alternative embodiment, a transmit station of a radio system includes a circuit to determine an angular power spectrum, a space-time encoder, and a transmitter.

Abstract: A method and apparatus for redistributing power radiated by an antenna comprised of a plurality of antenna elements. An antenna directivity estimator function is performed to screen out inappropriate antenna directivity profiles from a plurality of antenna directivity profiles, thereby determining one or more remaining, appropriate antenna directivity profiles. An optimizer function is performed on the remaining, appropriate antenna element directivities to determine a phase distribution for the antenna elements based on a desired power distribution for the antenna.

Abstract: An array antenna transmitter/receiver has an array antenna (10) composed of antenna elements and radio transmitting/receiving units (30-1 to 30-n) provided to the respective antenna elements, wherein calibration signals are generated at given time intervals in a burst, the calibration signals are subjected to frequency conversion, the frequency-converted calibration signals are fed to the radio transmitting/receiving units (30-1 to

Abstract: A method and apparatus for reducing electromagnetic interference (EMI) and jamming in Global Positioning System (GPS) receivers operating on rolling or spinning platforms and/or environments is provided. An antenna system having a pair of diametrically-mounted elements provides interferometric cancellation for spatial and polarization nulling of interference signals. The antenna system, operating in conjunction with multiplexing and anti-jamming electronics, provides interference suppression for a GPS receiver connected thereto. Interference cancellation is provided in jamming and non-jamming environments by selectively employing spatial or polarization nulling of the interference signal.

Abstract: A method and apparatus for wireless communications wherein a base station transmits a signal to sending data to a subscriber station through a signal beam that sweeps through the coverage area of the base station. User data addressed to the subscriber station is buffered until the signal beam angle of the signal beam allows efficient transmission. The base station may alter the beam sweep speed or the shape of the beam's radiation pattern over time to maximize system efficiency and capacity.

Abstract: An apparatus for simultaneously receiving a first signal from a non-terrestrial source and a second signal from a terrestrial source on the same or overlapping channels using a receive antenna with posteriorly-directed sidelobes is disclosed. The apparatus comprises at least one terrestrial transmitter transmitting information on at least one frequency simultaneously usable by at least one satellite transmitting to a satellite receive antenna having a sensitivity characterizable by a primary sensitive axis directed substantially at satellite. The terrestrial transmitter includes a azimuthal gain characteristic directed substantially away from the Earth's Equator. In an alternative embodiment, the terrestrial transmitter is disposed at a location defining a vector angularly displaced from the primary sensitive axis by an angle of less than 90 degrees. A method of transmitting information is also disclosed.

Abstract: A method, apparatus for reducing errors in a plurality of beacon beams is disclosed. The method comprises the steps of computing quantized channel weights {tilde over (W)}c from channel weights Wc for at least some of the channels; estimating the quantization error &Dgr;Ba for each of the beacon beams from a difference between the channel weights Wc and the computed quantized channel weights {tilde over (W)}c; and adding the estimated quantization error &Dgr;Ba to the beacon beams. Similarly, a beacon biases equivalent to the beacon asymmetry error can be computed by the ground beacon beam forming software and uploaded to the on-board software for error compensation. The apparatus comprises one or more means, such as a processor communicatively coupled to a memory storing instructions for performing these operations.

Abstract: A technique for steering a directional antenna such as may be used in a Wireless Local Area Network (WLAN) device. The technique detects signal parameters during reception of short sync pulses in the very beginning portion of a Packet Protocol Data Unit (PPDU) frame. As a result, the antenna can be steered to an optimum direction for reception prior to receiving other portions of a preamble that may be needed to acquire carrier signal phase and frequency.

Abstract: A method of tracking a signal from a moving signal source including commanding angular offsets to control an antenna to track a signal from a moving signal source taking into consideration directional changes of the signal and comparisons between actual and estimated trajectories of the moving signal source.

Abstract: A radio frequency communication device and method for tuning an antenna attached thereto are disclosed. A radio frequency communication device is disclosed comprising internal circuitry and an antenna having a plurality of antenna segments associated therewith. Each antenna segment is associated with the antenna in either series or parallel relation through at least one of a fuse and an antifuse. In testing and tuning, a comparison is made to indicate whether the antenna is too short or too long. If the antenna is too short, an antenna segment may be attached to the antenna by initiating an antifuse. If the antenna is too long, an antenna segment may be detached from the antenna by blowing a fuse. If it is indeterminate whether the antenna is too short or too long, an antenna segment may be either attached or detached, the test repeated, and the results of the repeated test compared with the prior test to determine whether the correct action was taken.

Abstract: A communications system (10) and method of operating the communications system includes a high altitude communication device (12) that communicates with a plurality of user terminals and a gateway station (30). The gateway station (30) couples the users to terrestrial networks (32) and other users. The high altitude communication device (16) has a controller that generates a second beam having the first frequency to a service (26). The stratospheric platform (12) does not generate the second beam within a blocking area. User terminals within the service area outside the blocking area are configured to receive the first beam and the second beam.

Abstract: A method and system is directed to aligning a point-to-multipoint access terminal to an access point. The access terminal provides an output signal, including first and second components, to a readout port. Signal strength that is associated with a received signal is encoded in the first component, while the authentication status of the communication link is encoded in the second component. The antenna alignment is adjusted while monitoring the signal strength via the readout port. The antenna is substantially aligned when the signal strength reaches a peak level. In one example, the signal strength is encoded in a DC component of the output signal, while the authentication status is encoded in an AC component of the output signal. The AC component of an AC encoded signal may have a varied amplitude and/or frequency.

Abstract: Methods and structures are provided for reducing pointing errors &zgr; of satellite antennas and for generating broad field-of-view satellite attitude acquisition patterns. In one method embodiment, satellite transmit beams have estimated pointing attitudes &bgr; and are transmitted to overlap on a ground-based receiving terminal which has a known terminal location &lgr; and which measures received signal strengths &agr;. Pointing errors &zgr; of the transmit beams are then determined from the estimated pointing attitudes &bgr;, the terminal location &lgr; and the signal strengths &agr; and the pointing errors &zgr; are subsequently reduced by revising the pointing attitudes &bgr;. Other method embodiments utilize known signal-strength functions and antenna signals with known signal parameters such as frequencies and/or modulations.

Abstract: A controller controls the automatic positioning of an antenna. The controller is arranged to position the antenna dependent upon a channel selected by a user, a location of a receiver tuned to the selected channel, and a location of a source of a signal associated with the selected channel.

Abstract: A system and method for positioning a dish antenna having a plurality of low noise block converters for the simultaneous reception of signals from a plurality of satellites in a direct broadcast satellite system. An integrated receiver/decoder alternately powers at least two low noise block converters to sample signals for comparison to a dynamic threshold value to detect a peak signal for each of the low noise block converters. When the peak signals are detected, they are compared to a dynamic master threshold to indicate a master lock for the system.

Abstract: An apparatus and a method for orienting an antenna to a transmitter, and an antenna using the apparatus are disclosed. The apparatus for orienting an antenna toward a transmitter, which is used with an antenna, comprises a shadow generating means fixedly mounted to the antenna so as to generate a shadow of the sun, and target indicating means for specifying a target point on a reflector, at which a predetermined portion of the shadow generated by the shadow generating means should be positioned when the antenna is correctly oriented toward the transmitter.

Abstract: A method of determining the position of geostationary satellites by means of signals of at least one navigation satellite. A determination is made of data concerning the transit times of the signals from the at least one navigation satellite to the geostationary satellite by a device of the geostationary satellite, and a determination is made of navigation data of the at least one navigation satellite by an independent navigation device. A determination is made of data concerning the system time of the at least one navigation satellite by an independent navigation device, and a data exchange occurs between the geostationary satellite and the navigation device in order to determine position data of the geostationary satellite from the transit times, the navigation data as well as the system time of the at least one navigation satellite.

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: Method and antenna system used to point at least an antenna with respect to one or more other antennas, one of the antennas being a transmission antenna with an opening beam &thgr;e associated with a rotation speed Re, to cover an angular sector Se transmitting a signal every Tb seconds and another antenna being a reception antenna with an opening beam &thgr;r associated with a rotation speed Rr to cover an angular sector Sr, comprising at least the following steps

Abstract: The present invention relates to an antenna alignment meter which comprises a receiver for detecting a signal with predetermined characteristics and outputting data pertaining to the detection of the signal, and a controller responsive to the data from the receiver for controlling generation of an indicator that signal has been received. The meter can be used for aligning an antenna with a signal source. The meter is arranged to monitor signals received by the antenna and to provide an indication of correct alignment of the antenna with a desired signal source when a signal of a predetermined frequency, polarization, symbol rate and error correction is received.

Abstract: Methods and structures are provided for reducing pointing errors &zgr; of satellite antennas and for generating broad field-of-view satellite attitude acquisition patterns. In one method embodiment, satellite transmit beams have estimated pointing attitudes &bgr; and are transmitted to overlap on a ground-based receiving terminal which has a known terminal location &lgr; and which measures received signal strengths &agr;. Pointing errors &zgr; of the transmit beams are then determined from the estimated pointing attitudes &bgr;, the terminal location &lgr; and the signal strengths &agr; and the pointing errors &zgr; are subsequently reduced by revising the pointing attitudes &bgr;. Other method embodiments utilize known signal-strength functions and antenna signals with known signal parameters such as frequencies and/or modulations.

Abstract: A method and apparatus are provided for tracking a signal source using an antenna with a predetermined beamwidth. The method includes the steps of measuring a signal level from the signal source along an arc within the beamwidth of the antenna, determining a rate of change of the measured signal level along the arc and solving for a position on the arc where the determined rate of change of the signal level substantially equals zero.

Abstract: A system for managing return channel bandwidth in a two-way satellite communication network is disclosed. A plurality of transceivers are configured to transmit backlog information over a return channel via a satellite. The backlog information specifies an amount of queued traffic for the respective transceivers. A hub is configured to receive the backlog information and to allocate a predetermined amount of return channel bandwidth to each of the plurality of transceivers. The hub determines whether additional return channel bandwidth is available to accommodate a remaining backlog such that a bandwidth allocation amount is set to a level associated with one of the plurality of transceivers having the largest backlog. The hub selectively identifies a transceiver among the plurality of transceivers having a next largest backlog based upon the determined available return channel bandwidth.

Abstract: An antenna positioned (with rough alignment) on an aircraft is calibrated in position and orientation relative to the inertial navigation system of the aircraft by measuring the corresponding position and orientation parameters of the aircraft and a reference target relative to the Global Positioning System (GPS) and calculating differences between azimuth and elevation parameters of the target measured by the antenna control system and corresponding roll, pitch and heading parameters measured by the aircraft system, thereby providing bias parameters for the antenna output in the coordinates of the inertial navigation system.

Abstract: A method of directional radio communication between a first station (6) and a second station, comprising the steps of defining at the first station (6) a plurality of beam directions (b1-b8) for transmitting signals to said second station, each of said beam directions being selectable. A plurality of beam directions are selected at said first station in which a signal is to be transmitted form said first station to said second station. Said signal i transmitted in said plurality of beam directions, whereby the power level of the signal transmitted in each of said selected plurality of beam directions is individually selectable.

Abstract: A method and system for controlling a movable appendage on an aerospace vehicle independent from the position of the aerospace vehicle. First and second beacons containing actual position information for the movable appendage are tracked and acquired by first and second beacon tracking sites. The beacon tracking sites report the azimuth and elevation data relating to the position of the movable appendage to a processor where a correction command is determined based on an error calculated from the position data and a desired position. The correction command is communicated to the movable appendage so that appropriate correction to the desired position can be made.

Abstract: A method and system is directed to aligning a point-to-multipoint access terminal to an access point. The access terminal provides an output signal, including first and second components, to a readout port. Signal strength that is associated with a received signal is encoded in the first component, while the authentication status of the communication link is encoded in the second component. The antenna alignment is adjusted while monitoring the signal strength via the readout port. The antenna is substantially aligned when the signal strength reaches a peak level. In one example, the signal strength is encoded in a DC component of the output signal, while the authentication status is encoded in an AC component of the output signal. The AC component of an AC encoded signal may have a varied amplitude and/or frequency.

Abstract: A method and apparatus are provided for tracking a signal source using an antenna with a predetermined beamwidth. The method includes the steps of measuring a signal level from the signal source along an arc within the beamwidth of the antenna, determining a rate of change of the measured signal level along the arc and solving for a position on the arc where the determined rate of change of the signal level substantially equals zero.

Abstract: An apparatus and method, for determining an instrument boresight heading. The apparatus comprises an instrument having a boresight, an elevation positioner for positioning the elevation of the instrument boresight having an elevation axis, an azimuth positioner for positioning the azimuth of the instrument boresight having an azimuth axis and a sensor including a gyro having a sensitive axis. The method comprises recording a first output of a gyro of an azimuth positioner having an instrument boresight azimuth heading in a first position, rotating the azimuth positioner to a second position, recording a second output of the gyro and rotating the azimuth positioner to a third position, recording a third output of the gyro and determining the azimuth heading relative to true north from the first, second and third output.

Abstract: An apparatus and method for aligning the antennas of two transceivers of a point-to-point wireless millimeter wave communications link. A narrow band oscillator power source is substituted for the signal transmitting electronics associated with a first antenna and a power detector is substituted for the signal receiving electronics associated with a second antenna. In preferred embodiments after a first alignment procedure is performed, the procedure is repeated with an oscillator power source connected to the second antenna and a power detector connected to the first antenna. In other preferred embodiments the antennas are pre-aligned using a signaling mirror or a narrow beam search light or laser. After the antennas are aligned the transceiver electronics are reconnected. In preferred embodiments the communication link operates within the 92 to 95 GHz portion of the millimeter spectrum and provides data transmission rates in excess of 155 Mbps.

Abstract: A method for aligning an antenna polarization axes of a dual polarized end-user terminal having an antenna. The antenna is aligned with a satellite in relation to azimuth and elevation. The end-user terminal is configured in an alignment mode to produce a first output corresponding to a first component of a received signal parallel to a first polarization axis of the antenna and a second output corresponding to a second component of the received signal parallel to a second polarization axis of the antenna. The first polarization axis is orthogonal to the second polarization axis. The method includes the steps of: receiving a linearly polarized signal; autocorrelating the first output and the second output to produce a measurement of autocorrelation; and adjusting the antenna polarization axes to minimize the measurement of autocorrelation.

Abstract: A fixed terrestrial user terminal antenna for use with a satellite communication systems in which satellites orbit earth in a constellation comprised of a plurality of spaced orbital planes with each orbital plane of the plurality of orbital planes having a plurality of satellites. The user terminal antenna comprising a base with a tilt plate connected to the base. The tilt plate having a one-dimensional electronically scanned phased array antenna that scans along a single axis is attached to the tilt plate so that the array antenna tilts with the tilting of the tilt plate. The array antenna tracks individual satellites of the plurality of satellites in an orbital plane of the plurality of orbital planes as the individual satellites travel through a field of view of the array antenna.

Abstract: Equipment and methods for aligning the antennas of two transceivers of a point-to-point wireless millimeter wave communications link and keeping them aligned. Each of two communicating antennas is equipped with a telescopic camera connected to a processor programmed to recognize landscape images. The processors are programmed to remember the pattern of the landscape as it appears when the antennas are aligned. Each of the cameras then view the landscape periodically or continuously and if the landscape in view changes by more than a predetermined amount a signal is provided to indicate a misalignment. An operator can then take corrective action or alternatively the antenna system can be configured for remote or automatic realignment based of feedback from the camera.

Abstract: An antenna alignment apparatus and alignment method is used to effectively position an antenna used in a satellite communication system on the satellite orbital arc, and to ensure that a proper antenna polarization is achieved during installation or alignment of a remote station antenna. The apparatus includes a secondary receiving device mounted on the feed arm of the antenna at a specified distance from the primary receiving device located on the primary plane of the antenna. An antenna using this system and method may be properly aligned on the orbital arc using only simple receiving equipment.

Abstract: A radiotelephone system for motor vehicles, having a group antenna system with a plurality of antenna elements, and a mobile radiotelephone with a high-frequency input for receiving radio signals. The group antenna system contains controllable phase and/or amplitude adjusting elements, which are set so that a directed reception with a main receiving direction is available. The controllable phase and/or amplitude adjusting elements are controlled by a processor for tracking the main receiving direction azimuthally in the direction of a fixed station with the help of a tracking signal. Controllable switching-elements for reversing antenna signals for diversity reception are integrated in the signal paths of the group antenna system so that the azimuthal main direction of reception is tracked with a defined tracking by setting a combination of the switching positions of the controllable switching elements.

Abstract: A system and method for RF autotracking multiple antennas (preferably located on a spacecraft) to compensate for disturbances experienced by the antennas. The system and method estimate high frequency errors associated with all of the antennas. The high frequency errors may be estimated using a currently selected antenna and a high-pass filter. The high frequency errors may be estimated using a sensor mounted on the spacecraft, such as a gyro or star tracker, or may be estimated using information, such as planned thruster firings, for example, from a spacecraft attitude control system. Alternatively, the high frequency information may be estimated using any combination of data from these sources. Low frequency errors are estimated using measurements from each selected antenna. The algorithm implemented in the present invention explicitly accounts for the frequency content of each disturbance source.

Abstract: A low-profile antenna system to be mounted to a moving vehicle for receiving signals, such as from a Digital Broadcast Satellite, includes a base for mounting to the surface of the vehicle, a platen mounted to the base for rotation, an azimuth drive motor for rotating the platen, an array of half-cylinder antenna elements mounted to the platen, an elevation drive motor for pivoting the antenna elements individually about their axes to change the elevation at which the antenna elements are pointing, and a cover. The azimuth drive motor and the elevation drive motor together allow the array of antenna elements to be pointed at a satellite over a wide range of vehicle orientations.