Hughes Network Systems, LLC

Hughes Electronics Corporation

The Directv Group, Inc.

Stan Kay

Lin-Nan Lee

Mustafa Eroz

Bassel F Beidas

Rohit Iyer Seshadri

Liping Chen

A Roger Hammons, Jr

Yezdi F Antia

Udaya Bhaskar

Dave Roos

Frank Kelly

Jack Rozmaryn

Hesham El-Gamal

Adrian Morris

Robert Kepley

Andrew MacDonald

Jerry Dai

Anwer Khan

Neal David Becker

Gaguk Zakaria

Peter Hou

Daniel Raymond Wendling

Zhenliang Shi

Various arrangements for performing transmodulation of a forward feeder link are presented. A first data stream and a second data stream can be modulated into a higher-order modulation forward feeder link having a higher-order digital modulation scheme. A satellite can receive the higher-order modulation forward feeder link. The satellite can demodulate the higher-order modulator forward feeder link into a bit stream. This bit stream may then be remodulated and retransmitted as multiple forward user links.

Transmodulation for a multi-beam satellite communication system

A system for reducing antenna spillover in a satellite communications system is disclosed. The system may include an apparatus comprising an antenna terminal, which in turn may include a sub-reflector and a main reflector. The main reflector may include at least one of an extension, a shroud, and a serrated edge. The extension may be a full rim extension or a partial extension. The shroud may be a full shroud or a partial shroud. The serrated edge may include a straight serration or a curved serration, the serrated edge also having various dimensions and profiles. In some examples, the sub-reflector and the main reflector of the antenna terminal may be provided and configured to reduce antenna spillover in accordance with antenna performance and interference restrictions set forth by one or more governing bodies.

Reducing reflector antenna spillover lobes and back lobes in satellite communication systems

Systems and methods for mitigating interference from a satellite gateway antenna are disclosed herein. In an embodiment, a method for mitigating interference from a satellite gateway antenna includes locating a satellite gateway antenna that shares a frequency band with a 5G service, determining that the satellite gateway antenna causes radiation that interferes with a base station operating using the 5G service, and mounting at least one panel to reduce the radiation in a direction of the base station operating using the 5G service.

Systems and methods for mitigating interference from satellite gateway antenna

An apparatus and method are disclosed for mitigating pointing errors resulting from satellite antennas. Reports are received from terminals in a beam hopping satellite communication system, and a pointing error associated with a satellite antenna is determined. The best beam for communicating with each terminal is selected based on the pointing error. A beam list containing the instantaneous traffic demand of terminals for each beam in the system is generated. An active beam set is then selected from the beam list for transmitting data during the next hop in the satellite communication system.

Pointing error mitigation

A method is provided for interleaving frequency reuse plans of multiple satellites to form an aggregate frequency reuse cell plan. A first plurality of spot beams is generated by a first satellite for a first frequency reuse plan based on radio frequency (RF) spectrum bands. A second plurality of spot beams is generated by a second satellite for a second frequency reuse plan based on the RF spectrum bands. The first and second plurality of spot beams are interleaved to generate an aggregate frequency reuse cell plan. According to the aggregate frequency reuse plan, each of a first plurality of cells is covered by a combination of at least two of the plurality of spot beams of the first satellite, and each of a first plurality of cells is covered by a combination of at least two of the plurality of spot beams of the second satellite.

Approaches for achieving improved capacity plans for a satellite communications system via interleaved beams from multiple satellites

A communications system includes a base station that is configured to transmit a signal that is modulated according to a predetermined modulation scheme and an orthogonal frequency division multiplexing scheme, wherein the signal is encoded using space-frequency coding. The base station includes a plurality of multiple-input multiple-output (MIMO) transceivers. The system includes a terminal that is configured to receive the modulated signal. The above arrangement is particularly applicable to providing multichannel multipoint distribution services (MMDS) over a radio communications system.

Space-time coded OFDM system for MMDS applications

The present invention provides a communication system for use with a first source signal and a second source signal. The first source signal is on a first channel and includes M symbols, where M is an integer greater than 1. The second source signal is on a second channel and includes X symbols, where X is an integer greater than 1. The first channel is different from the second channel. The communication system includes a first modulator unit, a second modulator unit and an adder. The first modulator unit can generate a first modulated signal based on the first source signal and includes a first inter-symbol distortion estimating unit and a first stage predistortion unit. The second modulator unit can generate a second modulated signal based on the second source signal and includes a second inter-symbol distortion estimating unit and a predistortion unit. The adder can generate an added signal based on the first modulated signal and the second modulated signal. The first inter-symbol distortion estimating unit can generate a distorted symbol vector based on an estimate of a distortion of the first through (a&#x2212;1)-th symbols and an estimate of a distortion of the (a+1)-th through M-th symbols, where 1&#x2266;a&#x2266;M. The first stage predistortion unit is operable to generate a predistorted symbol &#xe3; based on the symbol a of the first plurality of symbols and the distorted symbol vector. Further, a receiver unit can cancel interference in the received signals to account for adjacent channel interference.

System and method for combined predistortion and interference cancellation in a satellite communications system

A communication system balances message traffic between return channel groups and within the groups, so that the user does not control the specific transmission frequency used. Uplink frequencies and bandwidths for the return channels are set by the system in a return channel control message in the broadcast signal so as to account for system and return channel group loading, and to account for user message backlogs. An initial transmission from a remote user may be made using an ALOHA-type burst signal that provides a message backlog to the control station, and is made on a frequency determined from a randomly weighted, load-based frequency selection process. The system, and not the individual users determine the frequency and channel allocations. For large backlogs or priority users, periodic bandwidth is provided. A method for balancing loads among and between groups of return channels in the communication system includes requesting return channel bandwidth in an uplink message from a remote user to a control station. The uplink message may include a both a backlog indicator and a bandwidth allocation request provided to a Network Operations Center (NOC) which can be used to set the return channel bandwidth and frequency for the remote uplink. A user message is transmitted on the designated return channel frequency using bandwidth allocated in accordance with the backlog indicator and a bandwidth allocation request so that traffic loads are maintained in balance between established return channel frequency groups, and within each return channel frequency group.

Apparatus and method for efficient TDMA bandwidth allocation for TCP/IP satellite-based networks

A satellite communications system having a fallback mode of operation, during which uplink signals are transmitted at a reduced data rate, is provided with a novel fallback mode ingress/egress mechanism utilizing a combination of a feedback-based fade detection scheme and fade detection based on parameters independent of the uplink signal transmission. The fallback mode ingress/egress mechanism is responsive to a satellite beacon signal independent of the uplink signals and to feedback signals produced by the satellite in response to the uplink signals, for requesting a satellite terminal to switch into the fallback mode when either the feedback signals indicate an increase in a fade level or in response to a first value of a selected parameter of the satellite beacon signal. The fallback mode ingress/egress mechanism requests the satellite terminal to switch out of the fallback mode in response to a second value of the satellite beacon signal parameter.

Fallback mode ingress/egress mechanism for satellite communication system

An uplink power control system for terminals in a satellite communication system provides closed loop power control using feedback signals generated at a satellite. The satellite performs inter-beam routing of uplink signals from satellite terminals, and processing of uplink signals to generate terminal transmission-specific feedback information that is transmitted in downlink signals to the terminals. The satellite also generates a beacon signal. An uplink power control algorithm at each terminal uses the beacon signal and feedback data to adjust transmit power.

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Rockville, MD, United States of America

Stan Kay