Abstract: A processor for use in a satellite communications system includes a selector that is configured to select a subset of a plurality of spatially diverse satellite signals based upon a location of a radioterminal. The processor further includes a signal processor that is configured to detect a return-link transmission from the radioterminal responsive to the selected subset of the spatially diverse satellite signals. The respective spatially diverse satellite signals may include respective signals corresponding to respective antenna elements of a satellite. The selector and the signal processor may be ground based.
Type:
Grant
Filed:
May 11, 2005
Date of Patent:
September 11, 2012
Assignee:
ATC Technologies, LLC
Inventors:
Peter D. Karabinis, Santanu Dutta, Gary G. Churan
Abstract: Apparatus, methods and computer program products that support inter-PLMN coordination in registration and handover operations are provided. Hysteresis is introduced in registration of radioterminals in a hybrid terrestrial/satellite mobile communications environment. Inter-PLMN handover techniques are provided, including techniques for coordination of communication of timing information and traffic channel controls.
Type:
Grant
Filed:
March 1, 2010
Date of Patent:
August 21, 2012
Assignee:
ATC Technologies, LLC
Inventors:
Jérome Tronc, Christian Calamarte, Michel Mouly, Santanu Dutta
Abstract: Two satellite communications systems can use the same frequency or frequencies in geographically overlapping footprints, without creating undue interference in a given system that is caused by the same frequency signal(s) that is/are used by the other system. In particular, an aggregate Effective Isotropic Radiated Power (EIRP) of the radioterminals and/or ancillary terrestrial components of a second satellite communications system in the common footprint is sufficiently low, and/or the receive antenna gain of a first satellite communications system is sufficiently low compared to the receive antenna gain of the second satellite communications system, so as to increase an aggregate receiver noise that is seen by the first satellite system receivers by an amount that does not substantially change a Quality of Service (QoS) of the first satellite communications system.
Abstract: A processor for use in a satellite communications system includes a selector that is configured to select a subset of a plurality of spatially diverse satellite signals based upon a location of a radioterminal. The processor further includes a signal processor that is configured to detect a return-link transmission from the radioterminal responsive to the selected subset of the spatially diverse satellite signals. The respective spatially diverse satellite signals may include respective signals corresponding to respective antenna elements of a satellite. The selector and the signal processor may be ground based.
Type:
Grant
Filed:
December 22, 2008
Date of Patent:
August 7, 2012
Assignee:
ATC Technologies, LLC
Inventors:
Peter D. Karabinis, Santanu Dutta, Gary G. Churan
Abstract: Methods of operating a transceiver including an antenna having a plurality of antenna feed elements are presented. The methods include defining a plurality of antenna gain constraint values gk associated with K geographic constraint points within a geographic region, iteratively generating M antenna feed element weights wM that result in antenna response values fK at the K geographic constraint points based on the corresponding antenna gain constraint values gK, forming an antenna beam from the antenna to the geographic region using the antenna feed element weights wM, and communicating information over the antenna beam. Related transceivers, satellites, and satellite gateways are also disclosed.
Abstract: A method of transmitting information in a wireless communications system can be provided by selectively applying filtering to transmission of a carrier signal of a first band of frequencies of a wireless communications system based on a frequency separation distance between a frequency content of the carrier signal and a second band of frequencies allocated to a communications system other than the wireless communications system.
Abstract: Methods for controlling orthogonal frequency division multiple access (OFDMA) communications over satellite links. The methods include estimating a differential delay in a satellite spotbeam between a mean propagation delay in the spotbeam and a propagation delay between a user terminal in the spotbeam and a satellite, estimating an overlap between an OFDMA uplink frame and an OFDMA downlink frame as a result of the differential delay, and providing a guard band in the OFDMA uplink frame and/or the OFDMA downlink frame to reduce an overlap between remaining portions of the OFDMA uplink frame and the OFDMA downlink frame other than the guard band. Corresponding systems and devices are also disclosed.
Type:
Grant
Filed:
June 7, 2007
Date of Patent:
May 1, 2012
Assignees:
ATC Technologies, LLC, Thales Alenia Space France
Inventors:
Arif Ansari, Jean-Michel Bories, Michel Cohen, Erwan Corbel
Abstract: Information is transmitted from a radioterminal to a first base station via a first wireless link. A satellite is used to route the information from the first base station to a second base station via second wireless links between the satellite and the first base station and between the satellite and the second base station. At least one of the second wireless links is more spectrally efficient than the first wireless link. Related methods, systems and devices are disclosed.
Type:
Grant
Filed:
November 21, 2006
Date of Patent:
May 1, 2012
Assignee:
ATC Technologies, LLC
Inventors:
Peter D. Karabinis, Boris Bogatin, Brian M. Deobald, Santanu Dutta
Abstract: A first and/or a second communications system may provide communications service over a geographic area. A method of operating the first and/or the second communications systems may include generating a measure of aggregate interference reaching a satellite of the second communications system substantially from devices of the first communications system. The measure of aggregate interference reaching the satellite of the second communications system may be transmitted to an element of the first communications system.
Abstract: Communications of a mobile station with a satellite mobile communications system and a terrestrial mobile communications system are coordinated. The mobile station is registered with the terrestrial mobile communications system and, responsive to the registration of the mobile station with the terrestrial mobile communications system, the mobile station is concurrently registered with the satellite mobile communications system. The concurrent registration may include implicitly registering the mobile station with the satellite mobile communications system, e.g., by storing information identifying the mobile station may be stored in a location register of the satellite mobile communications system responsive to the registration of the mobile station with the terrestrial mobile communications system, and maintaining synchronization between the two registrations. Authentication tokens may be pre-generated for quick re-registration with a satellite mobile communications system.
Abstract: Wireless communications are transmitted from at least two radioterminals to a base station co-channel over a return link using a return link alphabet. Wireless communications are also transmitted from the base station to the at least two radioterminals over a forward link using a forward link alphabet that has more symbols than the return link alphabet. The co-channel signals are deciphered at the receiver, while the radioterminals can use a smaller return link alphabet, which can reduce the power dissipation at the radioterminals.
Abstract: Methods of forming a beam to a wireless terminal from a transmitter including an antenna having a plurality of antenna feed elements include generating channel estimates at the wireless terminal, obtaining channel phase information from the channel estimates, quantizing the channel phase information to obtain quantized channel phase values, and transmitting the quantized channel phase values to the transmitter. The methods may further include receiving the quantized channel phase values at the transmitter, obtaining channel gain estimates, constructing channel estimates using the quantized channel phase values and the channel gain estimates, and determining transmit beamforming weights in response to the channel estimates. Related transmitters, wireless terminals, and communications systems are also disclosed.
Abstract: A space-based component, such as a satellite, is configured to receive wireless communications from radiotelephones in a satellite footprint over an uplink satellite radiotelephone frequency, and to transmit wireless communications to the radiotelephones over a downlink radiotelephone frequency. An ancillary terrestrial network, that may include one or more ancillary terrestrial components, is configured to transmit wireless communications to, and receive wireless communications from, the radiotelephones over the uplink satellite radiotelephone frequency in a time-division duplex mode.
Abstract: Methods are provided for predicting uplink interference potential to a mobile satellite system (MSS) generated by ancillary terrestrial components (ATCs) of an ancillary terrestrial network (ATN) and/or ATC radioterminals that are configured to terrestrially use/reuse satellite frequencies that are used and/or authorized for use by a MSS. The methods include measuring power transmitted by and/or received at one or more radioterminals communicating with one or more terrestrial networks and/or transmitted by and/or received at the one or more terrestrial networks communicating with the one or more radioterminals using terrestrial frequencies that are at least partially outside a range of the satellite frequencies. Uplink interference potential to the MSS generated by terrestrial use/reuse of satellite frequencies by the ATN and/or the ATC radioterminals is predicted responsive to the measured power. Related ancillary terrestrial networks are also described.
Abstract: A space-based component, such as a satellite, is configured to receive wireless communications from radiotelephones in a satellite footprint over an uplink satellite radiotelephone frequency, and to transmit wireless communications to the radiotelephones over a downlink radiotelephone frequency. An ancillary terrestrial network, that may include one or more ancillary terrestrial components, is configured to transmit wireless communications to, and receive wireless communications from, the radiotelephones over the downlink satellite radiotelephone frequency in a time-division duplex mode. By terrestrially transmitting and receiving wireless communications over the downlink satellite radiotelephone frequency in a time-division duplex mode, interference at the space-based component and/or at the gateway, by the ancillary terrestrial network and/or the radiotelephones due to terrestrial reuse of cellular satellite frequency spectrum, may be reduced or eliminated.
Abstract: Processing return feeder link signals at a satellite gateway including a first and second receive antennas includes receiving first and second return feeder link signals at the first and second receive antennas, respectively, modulating a phase of the first return feeder link signal to form an adjusted first feeder link signal, combining the adjusted first feeder link signal with the second return feeder link signal to form a combined feeder link signal, detecting periodic amplitude variation in the combined feeder link signal, and shifting a phase of the first return feeder link signal to reduce periodic amplitude variation in the combined feeder link signal.
Abstract: Methods, radioterminals, and broadcast message generation consoles provide location-based broadcast messaging for users. A method of operating a radioterminal can include receiving at the radioterminal over a wireless air interface a broadcast message that includes region information that defines a geographic region of applicability. A determination is made at the radioterminal whether the radioterminal is located in the region of applicability. A functional mode of the radioterminal is activated in response to the radioterminal being in the region of applicability. The functional mode may include activating a user interface of the radioterminal.
Abstract: A radioterminal communications system includes an ancillary terrestrial component configured to receive from at least some of a plurality of radioterminals using frequencies from a first satellite frequency band (e.g., an L-band) and to transmit to at least some of the plurality of radioterminals using frequencies from a second satellite frequency band (e.g., an S-band). The system further includes a space-based component configured to communicate with the plurality of radioterminals using at least some of the frequencies from the first satellite frequency band and/or at least some of the frequencies from the second satellite frequency band. In some embodiments the ancillary terrestrial component communicates with radioterminals using a Time Division Duplex (TDD) mode and the space-based component communicates with the same or other radioterminals using a Frequency Division Duplex (FDD) and/or a TDD mode.
Abstract: A radioterminal may include a transceiver, a hands-free interface, and a satellite/hands-free interlock. The transceiver may be configured for space-based communications and for terrestrial wireless communications. The satellite/hands-free interlock may be configured to prevent the transceiver from transmitting space-based communications unless the hands-free interface is activated. Related methods are also discussed.
Abstract: A satellite radiotelephone system includes a space-based component, a plurality of ancillary terrestrial components, and a plurality of radiotelephones. The space-based component is configured to provide wireless radiotelephone communications using satellite radiotelephone frequencies. The plurality of ancillary terrestrial components include a plurality of ancillary terrestrial component antennas configured to provide wireless radiotelephone communications using at least one of the satellite radiotelephone frequencies in a radiation pattern that increases radiation below the horizon compared to above the horizon. The plurality of radiotelephones are configured to communicate with the space-based component and with the plurality of ancillary terrestrial components. Each radiotelephone also includes a GPS signal processor and a GPS mode filter that is configured to suppress energy at (1575.42??) MHz, where 0<??16.42 MHz. Related radiotelephones and methods are also discussed.