With Beam Steering Patents (Class 342/354)
  • Patent number: 7129889
    Abstract: A method and apparatus for computing a lever arm correction between a wide beam coverage antenna and a steerable spot beam antenna of a navigational satellite is disclosed. A navigation receiver computes the lever arm correction using information from the navigational satellite that allows both the position of the navigational satellite and the navigational receiver to be determined using a known geometry of the steerable spot beam antenna and a prescribed satellite attitude maneuver profile.
    Type: Grant
    Filed: October 10, 2005
    Date of Patent: October 31, 2006
    Assignee: The Boeing Company
    Inventors: Kevin M. O'Brien, Jonathan A. Tekawy
  • Patent number: 7123876
    Abstract: A low profile, vehicle mounted, in-motion tracking, satellite antenna includes a pair of antenna assemblies mounted in parallel on a rotatable platform. Each antenna assembly includes two subreflectors with a plastic matching element. The outputs of the two antenna assemblies are coupled with a single phase shifter. The combined outputs are retransmitted to a receiver inside the vehicle. The satellite antenna also includes a receiver for receiving channel selection data and/or for providing two-way communication with equipment inside the vehicle. The antennae, transmitter and receiver are self-powered by a storage device which is charged by a wind driven generator. A retractable radome lowers to a lower profile when the antenna is not in use.
    Type: Grant
    Filed: November 1, 2001
    Date of Patent: October 17, 2006
    Assignee: Motia
    Inventors: James June-Ming Wang, ChauChin Yang, Wen Yen Lin
  • Patent number: 7110716
    Abstract: A dual-band multiple beam antenna system for a communications satellite sharing a set of reflector antennas for the transmit and receive frequencies. One set of reflectors is common to both the downlink and uplink frequencies. The feed horns are diplexed and exhibit frequency-dependent radiation patterns that separate the phase centers over the downlink and uplink frequency bands to obtain dual-band performance. The focal point of the reflector is in close proximity to the phase center corresponding to the downlink frequency band. The phase center for the uplink frequency band is spaced a predetermined distance from the phase center of the downlink frequency band. According to the present invention, the uplink frequencies are defocused and the downlink frequencies are focused thereby creating identical radiation patterns at both frequency bands and over the coverage region of the communications satellite.
    Type: Grant
    Filed: January 30, 2002
    Date of Patent: September 19, 2006
    Assignee: The Boeing Company
    Inventors: Sudhakar K. Rao, David Bressler, Arun Bhattacharyya
  • Patent number: 7107012
    Abstract: A radio antenna of a radio base station is a directional antenna. The antenna searches for a peripheral radio base station by changing the directivity of the antenna. An operating channel and electric field intensity of the other base station are acquired by the searching and then stored as positional information. The operating channel of the base station, the directivity of the antenna, and a radio wave intensity communication area are set according to the acquired positional information. Further, the positional information is transmitted and received to and from the other base station to set the base station. When the base station was moved or when external noise occurred abruptly, channel change and change of a cell shape of the directional antenna are carried out. Consequently, interference between the base stations can be minimized and optimum setting of the channel and communicatable area can be realized.
    Type: Grant
    Filed: March 17, 2004
    Date of Patent: September 12, 2006
    Assignee: Hitachi, Ltd.
    Inventors: Kenji Kashiwagi, Takashi Maruyama
  • Patent number: 7013137
    Abstract: This disclosure describes a method to generate large numbers of spot beams for multiple-beam satellite systems using smaller apertures. This is done by dividing the basic spot beam that has 3 to 4 dB of gain drop within the beam into a number of smaller 1-dB sub-beams. This has the effect of reducing the required peak gain for the antenna by 2–3 dB, thus reducing its size by as much as 50%. The frequency band allocated to the basic beam will be divided among the sub-beams. However, the frequency re-use among the basic beams can be maintained. Frequency allocations have to be coordinated among all beams. This concept is especially applicable to phased arrays using digital beam formers. The DBF complexity is a function of the number of array elements, and is less dependent on the number of beams. Reducing the array size, and consequently reducing the number of elements helps in reducing the complexity, power and mass of the DBF.
    Type: Grant
    Filed: July 16, 2001
    Date of Patent: March 14, 2006
    Assignee: Comsat Corporation
    Inventors: Amir I. Zaghloul, Ozlem Killic, Albert E. Williams
  • Patent number: 6993288
    Abstract: A method of coordinating communications between ground stations and fixed beam satellites is provided, wherein each beam of a satellite antenna is assigned a color to create a color pattern that matches a frequency reuse pattern for the antenna, thereby using the same frequencies in a different beam with the same color. In operation, a ground station requests a virtual channel number from a resource manager, which sends a virtual channel number that is not used by another ground station within a beam diameter of the requesting ground station. The ground station then determines the position of the satellite, the beam and beam color, and further computes the frequency, polarization, and time slot, among other information, to communicate with the satellite. A method is also provided for managing virtual channels that comprises a network manager that groups ground stations and limits the number of virtual channels per group.
    Type: Grant
    Filed: July 17, 2002
    Date of Patent: January 31, 2006
    Assignee: The Boeing Company
    Inventors: Michael de La Chapelle, David C. Morse, Leonard J. Quadracci
  • Patent number: 6993361
    Abstract: The present invention relates to a method and system using dynamic beam forming for wireless communication signals in a wireless network. Base stations and/or UEs are provided with antenna systems having a range of beam forming selections. Relative base station and UE locations are one type of criteria used to make beam forming decisions.
    Type: Grant
    Filed: November 27, 2002
    Date of Patent: January 31, 2006
    Assignee: InterDigital Technology Corporation
    Inventor: Prabhakar R. Chitrapu
  • Patent number: 6989786
    Abstract: Techniques for redirecting a satellite antenna beam from a satellite antenna of a satellite in an inclined orbit to a preferred satellite antenna beam pointing position on the earth are provided. Satellite antenna maneuver data is computed based upon information associated with the satellite, such as telemetry, orbital, and antenna nominal pointing information. Command code sequences are then generated that correspond to the maneuver data. The command codes are executable at the inclined orbit satellite to modify the antenna position. The generated command codes are then transmitted to the inclined orbit satellite to redirect the satellite antenna beam center to the preferred position.
    Type: Grant
    Filed: June 30, 2004
    Date of Patent: January 24, 2006
    Assignee: Intelsat Global Service Corporation
    Inventor: Guibin Dong
  • Patent number: 6972724
    Abstract: A self-correcting mobile antenna control system and method. A method is provided for controlling the direction of an antenna mounted on a vehicle. The method includes determining a position decision based on a direction change signal output from a direction sensor, determining an energy decision based on a signal strength indicator, combining the position decision and the energy decision to produce an antenna control signal, and adjusting the antenna's direction based on the antenna control signal. The system also operates to periodically calibrate itself to offset any sensor errors so that intensive calibration procedures can be avoided.
    Type: Grant
    Filed: June 9, 2004
    Date of Patent: December 6, 2005
    Assignee: Qualcomm Incorporated
    Inventors: Bin Tian, Judd Erlenbach
  • Patent number: 6936760
    Abstract: A space-based power system. The system maintains proper positioning and alignment of system components without using connecting structures. Power system elements are launched into orbit, and the free-floating power system elements are maintained in proper relative alignment, e.g., position, orientation, and shape, using a control system.
    Type: Grant
    Filed: November 26, 2003
    Date of Patent: August 30, 2005
    Assignee: Solaren Corporation
    Inventors: James E. Rogers, Gary T. Spirnak
  • Patent number: 6930636
    Abstract: Methods and structures are provided for reducing pointing errors ? 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 ? and are transmitted to overlap on a ground-based receiving terminal which has a known terminal location ? and which measures received signal strengths ?. Pointing errors ? of the transmit beams are then determined from the estimated pointing attitudes ?, the terminal location ? and the signal strengths ? and the pointing errors ? are subsequently reduced by revising the pointing attitudes ?. Other method embodiments utilize known signal-strength functions and antenna signals with known signal parameters such as frequencies and/or modulations.
    Type: Grant
    Filed: August 26, 2003
    Date of Patent: August 16, 2005
    Assignee: The Boeing Company
    Inventor: Richard Fowell
  • Patent number: 6929220
    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.
    Type: Grant
    Filed: June 18, 2003
    Date of Patent: August 16, 2005
    Assignee: The DIRECTV Group, Inc.
    Inventor: David W. Lloyd
  • Patent number: 6914557
    Abstract: A system and method for tracking a user. The system is adapted for use in a wireless communication system and creates a plurality of beams within a coverage area. A first beam is directed at a user in a first microcell and a number of additional beams illuminate microcells immediately adjacent the first microcell. The system is equipped with a mechanism for detecting movement of the user from the first microcell to one of the immediately adjacent microcells. On the detection of movement of the user, the system redirects the first beam from the first microcell to a second microcell, the second microcell being one of the adjacent microcells. In the illustrative embodiment, the system is implemented in a stratospheric platform based communication system including a hub adapted to communicate with a stratospheric platform. A transceiver and a phased array antenna are disposed on the platform to communicate with the hub and with the user. A second antenna is provided on the platform to communicate with the hub.
    Type: Grant
    Filed: September 5, 2001
    Date of Patent: July 5, 2005
    Assignee: The DIRECTV Group, Inc.
    Inventors: Donald C. D. Chang, Ying Feria, Weizheng Wang, Alan G. Cha, Ming U. Chang, Frank A. Hagen, Kar W. Yung
  • Patent number: 6911938
    Abstract: This invention reduces the number of amplifiers needed and thus reduces the weight of a multi-beam transmitting system. Each input beam is connected respectively to each switched terminal of an input switch. The fixed terminal of the input switch is connected to the input of an amplifier the output of which is connected to the fixed terminal of an output switch. Each switched terminal of the output switch is connected respectively to transmit feeds which are located off-set from the prime focus of a transmit reflector antenna. Both the input and the output switches are switched synchronously. The invention includes MMIC and high Tc superconducting transmit systems. The invention includes design to prevent single point failures and a design to transmit a large amount of RF power.
    Type: Grant
    Filed: April 3, 1997
    Date of Patent: June 28, 2005
    Inventor: Satyendranath Das
  • Patent number: 6895217
    Abstract: A system has a stratospheric platform with a payload controller and a phased array antenna having a plurality of elements. A gateway station communicates with the stratospheric platform. The gateway station scales the plurality of elements to form a reconfigurable plurality of beams. The gateway station communicates a control signal to the stratospheric platform to communicate a scaling of the elements. The stratospheric platform configures the elements of the phased array antenna according to the scaling using adaptive interference rejection. The gateway station has an adaptive beam processor coupled to user position files. The adaptive beam processor with the user position data can adaptively cancel interference from other beams.
    Type: Grant
    Filed: August 21, 2000
    Date of Patent: May 17, 2005
    Assignee: The DIRECTV Group, Inc.
    Inventors: Donald C. D. Chang, Alan Cha
  • Patent number: 6862271
    Abstract: Techniques to transmit data on a number of transmission channels in a multi-channel communication system using multiple transmission schemes requiring less channel-state information (CSI). These schemes may include a partial-CSI transmission scheme that transmits a single data stream on each transmit antenna selected for use and a “beam-forming” transmission scheme that allocates all transmit power to a single transmission channel having the best performance. Each transmission scheme may provide good or near-optimum performance for a specific range of operating conditions (or operating SNRs). These multiple transmission schemes may then be combined in a piece-wise fashion to form a “multi-mode” transmission scheme that covers the full range of operating conditions supported by the MIMO system. The specific transmission scheme to be used for data transmission at any given moment would then be dependent on the specific operating condition experienced by the system at that moment.
    Type: Grant
    Filed: February 26, 2002
    Date of Patent: March 1, 2005
    Assignee: Qualcomm Incorporated
    Inventors: Irina Medvedev, Jay Rod Walton, Mark Wallace
  • Patent number: 6853333
    Abstract: The beam pattern associated with a multi-beam antenna array is adjusted if a first beam of the beam pattern is overloaded. A lobe of a second beam of the beam pattern can be steered away from a main lobe of the first beam. Also, if a user is located in an area covered by a second beam which is adjacent to the first beam, a third beam of the beam pattern can be selected for effectuating communication with the user. If a user is located in an area covered by the first beam, another beam of the beam pattern can be selected for effectuating communication with the user.
    Type: Grant
    Filed: September 12, 2003
    Date of Patent: February 8, 2005
    Assignee: Telefonaktiebolaget LM Ericsson
    Inventors: Marten Ericson, Bo Hagerman, Bo Goransson, Sven Petersson
  • Patent number: 6844844
    Abstract: The invention concerns a system comprising a radiofrequency antenna stationed in an orbit around the earth, and illuminating means for transmitting and/or receiving likewise orbiting round the earth located on at least a satellite separate from the one bearing the antenna, the antenna being located in the illuminating field of said means. The invention is characterised in that the antenna is a radiofrequency antenna formed by a mesh generation of tiles and phase-shifting means connected thereto, the signals received by the tiles passing through the phase-shifting means before being assembled on said tiles, said phase-shifting and/or delaying means being capable of diverting the radiofrequency signals corresponding to one or several channels transmitted by the illuminating means to send them to the earth along one or several beams and/or of diverting the radiofrequency signals corresponding to one or several beams transmitted from the earth to send them to the illuminating means along one or several channels.
    Type: Grant
    Filed: March 28, 2000
    Date of Patent: January 18, 2005
    Assignee: Centre National d'Etudes Spatiales
    Inventor: Jean-Paul Aguttes
  • Publication number: 20040246190
    Abstract: A satellite antenna system (30) that employs a small phased antenna array (46) acting as a redundant antenna. Because the phased array (46) is steerable, it can be selectively directed to any of the cells (16) on the Earth (12) in the event that the LNA in an antenna channel (32) fails. The phased array (46) is switched into each antenna channel (32) after the channel front end (40) where a switch (56) used to switch in the phased array (46) is after the amplification in the channel (32). Therefore, the switch (56) does not significantly affect the noise figure of the channel front end (32).
    Type: Application
    Filed: June 3, 2003
    Publication date: December 9, 2004
    Inventor: Garrick Jon Harmon
  • Patent number: 6825806
    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.
    Type: Grant
    Filed: June 3, 2002
    Date of Patent: November 30, 2004
    Assignee: The Boeing Company
    Inventors: Ketao Liu, Richard Fowell, Yeong-Wei A. Wu, Rongsheng Li
  • Patent number: 6822579
    Abstract: A method and apparatus for collecting data downhole in a well bore, even during drilling operations, are disclosed. The apparatus generally comprises an antenna and some associated electronic circuitry. The antenna includes a plurality of arrayed transceiver elements and the electronic circuitry steers transmission or reception through the antenna by controlling the application of power to the array elements. In operation, a transceiver unit containing such an antenna is positioned proximate a remote sensor placed into a formation. An electromagnetic signal is then steered to communicate with the remote sensor over a wireless link.
    Type: Grant
    Filed: July 3, 2001
    Date of Patent: November 23, 2004
    Assignee: Schlumberger Technology Corporation
    Inventors: Jaideva C. Goswami, Albert E. Hoefel, Jacques R. Tabanou, Bradley S. Underwood
  • Patent number: 6781968
    Abstract: A system, apparatus and method provide wireless communications to a geographical area. The system includes at least one atmospheric platform serving as a central relay or node using a star network topology for the geographic area. The atmospheric platform carries a payload that comprises communications equipment. The system further includes a plurality of user equipment units located within the geographic area and at least one ground station or gateway for providing an information pathway between the user equipment units. The gateway has network processing and switching equipment for routing the information between the users. A wireless trunkline carries signals between the gateway and the atmospheric platform. The apparatus and method comprise gateway and payload uplink portions and downlink portions. The downlink portions aggregates and de-aggregates user generated information from the platform to the gateway.
    Type: Grant
    Filed: January 28, 2000
    Date of Patent: August 24, 2004
    Inventors: Nicholas J. Colella, George G. Chadwick
  • Patent number: 6762716
    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.
    Type: Grant
    Filed: December 13, 2002
    Date of Patent: July 13, 2004
    Assignee: The Boeing Company
    Inventors: Hanching G. Wang, Chih-Chien Hsu
  • Patent number: 6759978
    Abstract: A cross-link antenna system including a plurality of spacecraft in a constellation is provided. Each of the spacecraft includes an antenna. One or more of the antennas has a number of antenna elements that can be controllably energized. Determined or selected phases and amplitudes can be individually applied through phase shifters and amplifiers to the antenna elements. In determining phase values for energizing the antenna elements to provide the receive beam in the direction of the current transmit antenna of one of the spacecraft in the constellation, location information is obtained for the transmit spacecraft and each of the beam receiving spacecraft. Additionally, attitude information for each receive spacecraft is found and location information associated with each of the antenna elements for each receive antenna is obtained.
    Type: Grant
    Filed: March 21, 2002
    Date of Patent: July 6, 2004
    Assignee: Ball Aerospace & Technologies Corp.
    Inventor: Farzin Lalezari
  • Patent number: 6756937
    Abstract: A communication system including a first transceiver located on a first platform at a predetermined altitude. A first antenna is located on the first platform and connected to the first transceiver. A second antenna is connected to the other end of the first transceiver. A second transceiver is located on a ground hub physically and independent of the first platform. A third antenna is located on the ground hub and connected to the second transceiver. The third antenna is adapted to communicate with the second antenna. The first platform is maintained in a stratospheric orbit. A beamforming system is connected to the second transceiver and mounted on the ground hub. The beamforming system provides a beamformed signal from the second transceiver to the first transceiver effective to drive the first array antenna to radiate multiple beams to a surface, whereby the multiple beams create time varying and dissimilar footprints thereon.
    Type: Grant
    Filed: June 6, 2000
    Date of Patent: June 29, 2004
    Assignee: The DIRECTV Group, Inc.
    Inventors: Donald C. D. Chang, Ming U. Chang, Ying Feria, Weizheng Wang, Alan Cha, Kar W. Yung, Frank A. Hagen
  • Patent number: 6731240
    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.
    Type: Grant
    Filed: March 11, 2002
    Date of Patent: May 4, 2004
    Assignee: The Aerospace Corporation
    Inventors: Robert B. Dybdal, Denny D. Pidhayny
  • Patent number: 6727425
    Abstract: High-output transmitters are applied to a power generation satellite and a transmission antenna apparatus and a transmission antenna having an array antenna with a small number of element antennas and a reflecting mirror antenna is applied, thereby providing a power generation satellite and a transmission antenna apparatus in a space photovoltaic generation system comprising transmission antennas each having performance equivalent to that of a phased array antenna with a smaller number of transmitters and a smaller number of element antennas than those of a transmission antenna implemented as a phased array antenna.
    Type: Grant
    Filed: July 1, 2002
    Date of Patent: April 27, 2004
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kazuyuki Takada, Hiroyuki Satou, Izuru Naito, Izumi Mikami
  • Patent number: 6725013
    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.
    Type: Grant
    Filed: June 15, 2000
    Date of Patent: April 20, 2004
    Assignee: Hughes Electronics Corporation
    Inventors: Donald C. D. Chang, Weizheng Wang, Ying Feria, Ming U. Chang, Harold A. Rosen, Wah L. Lim
  • Patent number: 6723912
    Abstract: A power generation satellite has a photoelectric conversion unit for converting sunlight into electric energy, a transmission frequency conversion unit for performing frequency conversion of the electric energy to a microwave, a microwave control unit for controlling the amplitude, the phase, or the amplitude and the phase of the microwave, and a transmitting antenna for radiating the microwave. A plurality of the power generation satellites are placed in space to form a power generation satellite group and an array antenna having the transmitting antennas of the power generation satellites in the power generation satellite group as element antennas is formed.
    Type: Grant
    Filed: June 4, 2002
    Date of Patent: April 20, 2004
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Tomohiro Mizuno, Hiroyuki Sato, Izuru Naito, Izumi Mikami
  • Patent number: 6720918
    Abstract: A thermal distortion estimation system for delivering thermal time varying distortion of various spacecraft antenna is provided which includes a measurement signal outage indicator and a storage device containing time varying distortion data. A signal is generated indicating an outage for the system received by the spacecraft and then a generated time varying distortion of the system from a previous measurement history to predict the error resulting from the thermal distortion is employed to estimate the error.
    Type: Grant
    Filed: September 17, 2002
    Date of Patent: April 13, 2004
    Assignee: Space Systems/Loral, Inc.
    Inventors: Keith Reckdahl, Lawrence McGovern
  • Publication number: 20040056795
    Abstract: The beam pattern associated with a multi-beam antenna array is adjusted if a first beam of the beam pattern is overloaded. A lobe of a second beam of the beam pattern can be steered away from a main lobe of the first beam. Also, if a user is located in an area covered by a second beam which is adjacent to the first beam, a third beam of the beam pattern can be selected for effectuating communication with the user. If a user is located in an area covered by the first beam, another beam of the beam pattern can be selected for effectuating communication with the user.
    Type: Application
    Filed: September 12, 2003
    Publication date: March 25, 2004
    Applicant: Telefonaktiebolaget LM Ericsson
    Inventors: Marten Ericson, Bo Hagerman, Bo Goransson, Sven Petersson
  • Patent number: 6703970
    Abstract: The invention relates to a beam forming network of an active antenna with deployable sub-arrays. According to the invention, the network receives information on deformation of the relative position of two panels. Establishing the coherence of the signals takes account of this information to restore the received signals. The invention also provides a spacecraft including the above kind of network and further provides a beam forming method. The invention also provides a system including a craft of the above kind and at least one beacon transmitter station.
    Type: Grant
    Filed: August 1, 2002
    Date of Patent: March 9, 2004
    Assignee: Alcatel
    Inventors: Jean-Didier Gayrard, Laurent Martin, Gérard Caille
  • Patent number: 6695262
    Abstract: Methods and structures are provided that enhance the accuracy of the service attitude of an inclined-orbit spacecraft and, thereby, facilitate reduction of service error between a communication service area and the spacecraft's payload beam. The enhancement is realized by configuring a beacon-receiving antenna to have a beacon-receiving field-of-view that substantially matches a beacon-station window. Preferably, the beacon-receiving field-of-view is elongated and tilted to enhance its match with the beacon-station window in both size and orientation. The goals are also realized by configuring the beacon-receiving antenna to have a beacon-receiving field-of-view that is substantially smaller than the beacon-station window and successively steering a beacon-receiving boresight to successive beacon-receiving attitudes that maintain the beacon station within the beacon-receiving field-of-view over each solar day.
    Type: Grant
    Filed: December 7, 2001
    Date of Patent: February 24, 2004
    Assignee: The Boeing Company
    Inventors: Grant Wang, Richard Fowell
  • Patent number: 6676087
    Abstract: Methods and structures are provided that enhance the accuracy of the service attitude of an inclined-orbit spacecraft and, thereby, facilitate reduction of service error between a communication service area and the spacecraft's payload beam. The enhancement is realized by configuring a beacon-receiving antenna to have a beacon-receiving field-of-view that substantially matches a beacon-station window. Preferably, the beacon-receiving field-of-view is elongated and tilted to enhance its match with the beacon-station window in both size and orientation. The goals are also realized by configuring the beacon-receiving antenna to have a beacon-receiving field-of-view that is substantially smaller than the beacon-station window and successively steering a beacon-receiving boresight to successive beacon-receiving attitudes that maintain the beacon station within the beacon-receiving field-of-view over each solar day.
    Type: Grant
    Filed: January 30, 2003
    Date of Patent: January 13, 2004
    Assignee: The Boeing Company
    Inventors: Grant Wang, Richard Fowell
  • Patent number: 6671649
    Abstract: A position calculation method that calculates the correct position of a terminal even when errors are not distributed symmetrically for positive and negative values, by calculating the position of a terminal using the delay time of received signals. The method calculates a first range that is a difference between a range from the terminal to each of antenna and a range from the terminal to a base antenna, the range being calculated from a wireless signal delay time; calculates a second range that is a difference between a range from an assumed terminal position for calculation to each antenna and a range from the assumed terminal position for calculation to the base antenna; calculates a likelihood of the position of the terminal, repeats these procedures to obtain a point where the likelihood is maximized, and determines an obtained most likely solution as the position of the terminal.
    Type: Grant
    Filed: March 19, 2003
    Date of Patent: December 30, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Mikio Kuwahara, Tomoaki Ishifuji, Takashi Yano, Kenzaburo Fujishima
  • Patent number: 6670918
    Abstract: The present invention relates to a method of repainting a reflector array antenna comprising a plurality of radiating elements and being of the type that forms beams by computation, in which method each signal received by said antenna is sampled. The method comprises the following operations: estimating the depointing of the radiation pattern of the antenna to obtain a phase shift matrix, computing the discrete inverse Fourier transform of the signal samples supplied by the radiating elements, multiplying the phase shift matrix by the inverse Fourier transform of the sampled signal, and computing the discrete direct Fourier transform of the product of the phase shift matrix and the inverse Fourier transform of the sampled signal.
    Type: Grant
    Filed: June 20, 2002
    Date of Patent: December 30, 2003
    Assignee: Alcatel
    Inventors: Cécile Guiraud, Hervé Legay, Marie-Laure Boucheret
  • Patent number: 6667712
    Abstract: The beam pattern associated with a multi-beam antenna array is adjusted if a first beam of the beam pattern is overloaded. A lobe of a second beam of the beam pattern can be steered away from a main lobe of the first beam. Also, if a user is located in an area covered by a second beam which is adjacent to the first beam, a third beam of the beam pattern can be selected for effectuating communication with the user. If a user is located in an area covered by the first beam, another beam of the beam pattern can be selected for effectuating communication with the user.
    Type: Grant
    Filed: June 28, 2002
    Date of Patent: December 23, 2003
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Marten Ericson, Bo Hagerman, Bo Goransson, Sven Petersson
  • Patent number: 6653975
    Abstract: A method and computer program to configure feeds on a satellite (300, 310, 320) to provide for redundant coverage when a satellite (300, 310, 320) fails. Further, this method and computer program can enable the switching of feeds from commands from a ground station (30) to activate certain feeds and deactivate other feeds when demand for service changes. In addition, this method and computer program allow for repositioning of satellites so that when one satellite fails another satellite may take over its area of coverage by switching active feeds without the need for placing another satellite in orbit.
    Type: Grant
    Filed: November 21, 2001
    Date of Patent: November 25, 2003
    Assignee: Northrop Grumman Corporation
    Inventors: Steven L. Branscombe, William F. Courtney, Michael S. Munoz, Ray M. Nuber, Fritz B. Mezger
  • Patent number: 6650281
    Abstract: The invention relates to a receive (or send) antenna for a geosynchronous satellite of a telecommunications system intended to cover a territory divided into areas, the beam intended for each area being defined by a plurality of radiating elements, or sources, disposed in the vicinity of the focal plane of a reflector. The antenna includes at least one first matrix each input of which is connected to a radiating element and each output (or input) of which is connected to a corresponding input of an inverse Butler matrix by an amplifier and a phase-shifter. The phase-shifters move the areas or correct pointing errors.
    Type: Grant
    Filed: July 2, 2001
    Date of Patent: November 18, 2003
    Assignee: Alcatel
    Inventors: Gérard Caille, Yann Cailloce
  • Patent number: 6642883
    Abstract: A means and method to increase the beam traffic capacity, especially in high user density regions, of a multi-beam antenna communication system with multiple signals at any frequency transmitted (received) when in a transmit (receive) mode by canceling interference with neighboring signals. An interference cancellation network is provided for canceling the interference caused by the sidelobe(s) of at least one signal with one or more of the other signals in the network. Each power divider divides its input signal into one reference fractional signal and at least one non-reference fractional signal. Phase shifters/attenuators shift the phase and attenuate the amplitude of at least one of the non-reference fractional signals. Each power combiner combines its input reference fractional signal with at least one non-reference fractional signal into a composite signal emerging from the combiner. The phase/attenuation settings are selected to optimize the signal to interference ratio for each communications link.
    Type: Grant
    Filed: August 30, 2001
    Date of Patent: November 4, 2003
    Assignee: Lockheed Martin Corporation
    Inventors: Anthony Wykeham Jacomb-Hood, Vladimir Volman, Erik Lier
  • Publication number: 20030197637
    Abstract: A cross-link antenna system including a plurality of spacecraft in a constellation is provided. Each of the spacecraft includes an antenna. One or more of the antennas has a number of antenna elements that can be controllably energized. Determined or selected phases and amplitudes can be individually applied through phase shifters and amplifiers to the antenna elements. In determining phase values for energizing the antenna elements to provide the receive beam in the direction of the current transmit antenna of one of the spacecraft in the constellation, location information is obtained for the transmit spacecraft and each of the beam receiving spacecraft. Additionally, attitude information for each receive spacecraft is found and location information associated with each of the antenna elements for each receive antenna is obtained.
    Type: Application
    Filed: March 21, 2002
    Publication date: October 23, 2003
    Inventor: Farzin Lalezari
  • Patent number: 6631871
    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.
    Type: Grant
    Filed: September 23, 2002
    Date of Patent: October 14, 2003
    Assignee: Hughes Electronics Corporation
    Inventor: David W. Lloyd
  • Publication number: 20030142014
    Abstract: A dual-band multiple beam antenna system for a communications satellite sharing a set of reflector antennas for the transmit and receive frequencies. One set of reflectors is common to both the downlink and uplink frequencies. The feed horns are diplexed and exhibit frequency-dependent radiation patterns that separate the phase centers over the downlink and uplink frequency bands to obtain dual-band performance. The focal point of the reflector is in close proximity to the phase center corresponding to the downlink frequency band. The phase center for the uplink frequency band is spaced a predetermined distance from the phase center of the downlink frequency band. According to the present invention, the uplink frequencies are defocused and the downlink frequencies are focused thereby creating identical radiation patterns at both frequency bands and over the coverage region of the communications satellite.
    Type: Application
    Filed: January 30, 2002
    Publication date: July 31, 2003
    Inventors: Sudhakar K. Rao, David Bressler, Arun Bhattacharyya
  • Patent number: 6600921
    Abstract: A method and apparatus for producing contiguous spot beam communications coverage on the Earth's surface are disclosed. The apparatus comprises two contiguous beam patterns. The first contiguous beam pattern comprises a first set of cells and has a first set of frequencies. The second contiguous beam pattern comprises a second set of cells and has a second set of frequencies. The second contiguous beam pattern is spatially offset from the first contiguous beam pattern such that an edge of the first set of cells is offset from an edge of the second set of cells. Multiple two grid systems can maintain isolation performance of single grid system.
    Type: Grant
    Filed: February 16, 2000
    Date of Patent: July 29, 2003
    Assignee: Hughes Electronics Corporation
    Inventor: Stephan Pietrusiak
  • Patent number: 6595469
    Abstract: Attitude determination and control systems are provided that combine attitude measurements from all spacecraft payloads to determine a master attitude estimate for a master payload and relative slave attitude estimates for the remaining slave payloads. These estimates are then used to control the attitudes of spacecraft elements that correct the absolute and relative attitude errors. These systems significantly enhance attitude accuracy when compared to systems that realize independent payload estimates, determine payload attitudes. These systems also provide significant processing advantages (e.g., simpler algorithms, reduced data throughput and slower processing rate).
    Type: Grant
    Filed: October 28, 2001
    Date of Patent: July 22, 2003
    Assignee: The Boeing Company
    Inventors: Rongsheng Li, Yeong-Wei A. Wu, Hanching Grant Wang
  • Patent number: 6594226
    Abstract: Disclosed is a method and apparatus for enhancing diversity gain without reducing data rate by increasing the number of antenna elements and configuring the antenna elements for improving signal-to-noise ratio at a receiver. The antenna array comprise a first antenna group with at least two antenna elements and a second antenna group with at least one antenna element. The first and second antenna groups are spaced approximately ten carrier wavelengths or more apart from each other, and the antenna elements belonging to the first antenna group are spaced approximately a half carrier wavelength or less apart from each other. A plurality of data streams is generated from a signal and used to produce a first and second plurality of representative data streams. Each of the first plurality of representative data streams is phase-shifted and encoded using different orthogonal codes.
    Type: Grant
    Filed: December 15, 1999
    Date of Patent: July 15, 2003
    Assignee: Lucent Technologies Inc.
    Inventors: Roger David Benning, R. Michael Buehrer, Robert Atmaram Soni
  • Patent number: 6594469
    Abstract: In a communication satellite constellation which uses CDMA and multiple spot beams for point-to-point communication, a system is provided for broadcasting regionally related information within a spot beam by establishing a Frequency/Walsh Code Tiling over the Earth's surface, and enabling a user terminal at a given position to tune to an appropriate frequency and Walsh Code to receive the information broadcast from a satellite over a forward beam downlink. The information, e.g. regional messages such as local weather or traffic, is transmitted to the satellite from a ground station or gateway that receives the information from a Broadcast Processing Center. In a preferred embodiment a dedicated Frequency Division Multiplex (FDM) channel within each spot beam transmits the regional broadcast messages at the Tiles in accordance with the Walsh Code designations of the Tiles.
    Type: Grant
    Filed: August 29, 2000
    Date of Patent: July 15, 2003
    Assignee: Globalstar L.P.
    Inventors: John Serri, Michael J. Sites, Vijaya Gallagher
  • Patent number: 6570535
    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.
    Type: Grant
    Filed: March 13, 2002
    Date of Patent: May 27, 2003
    Assignee: Space Systems/Loral, Inc.
    Inventors: Homer D. Stevens, Keith Reckdahl, Xenophon Price
  • Patent number: 6570528
    Abstract: A synthesized reflector surface (12) for directing communication signals (27) in a communication system (10) that operates in a plurality of orbital slots and to a plurality of regions (28) within a first coverage area (30) is provided. The synthesized reflector surface (12) includes a plurality of contiguous profile surfaces (40) that form the reflector surface (12). Each of the plurality of contiguous profile surfaces (40) alters the phase-of the communication signals (27) to provide a first gain for a first satellite orbit location (32) and a second gain for a second satellite orbit location (34). The plurality of contiguous profile surfaces (40) directs the signals from the location (32) in a first orientation to the first coverage area (30) or from the location (34) in a second orientation to the first coverage area (30). A method is provided for synthesizing the reflector surface (12).
    Type: Grant
    Filed: November 9, 2001
    Date of Patent: May 27, 2003
    Assignee: The Boeing Company
    Inventors: Sudhakar Rao, Jack Bauer, Chih-Chien Hsu, Robert Rink
  • Publication number: 20030095064
    Abstract: A method and computer program to configure feeds on a satellite (300, 310, 320) to provide for redundant coverage when a satellite (300, 310, 320) fails. Further, this method and computer program can enable the switching of feeds from commands from a ground station (30) to activate certain feeds and deactivate other feeds when demand for service changes. In addition, this method and computer program allow for repositioning of satellites so that when one satellite fails another satellite may take over its area of coverage by switching active feeds without the need for placing another satellite in orbit.
    Type: Application
    Filed: November 21, 2001
    Publication date: May 22, 2003
    Inventors: Steven L. Branscombe, William F. Courtney, Michael S. Munoz, Ray M. Nuber, Fritz B. Mezger