Hughes Network Systems, LLC

The Directv Group, Inc.

Dtvg Licensing, Inc.

Hughes Electronics Corporation

Communications Satellite Corporation

Comsat Corporation

Other

Lin-Nan Lee

Mustafa Eroz

Feng-Wen Sun

Rohit Iyer Seshadri

Liping Chen

Neal David Becker

Khalid Karimullah

Bassel F Beidas

Stanley Edward Kay

Adam Von Ancken

Victor Liau

Stan Kay

Yimin Jiang

Chi-Jiun Su

Bob Cassagnol

Dan Fraley

Ernest C Chen

Joseph Santoru

Guangcai Zhou

Tung-Sheng Lin

Shamik Maitra

Dennis Lai

Ajit Shenoy

Neal D Becker

A Roger Hammons, Jr

Anthony Robert Noerpel

Yezdi F Antia

Udaya Bhaskar

Peter Hou

Jack Rozmaryn

Hesham El-Gamal

Andrew MacDonald

Kamran Etemad

Lakshmi Iyer

Scott D Casavant

Satyajit Roy

Kuriacose Joseph

John Corrigan

Ashok D Mehta

Farhad Hemmati

Walter Kepley

Ashok K Rao

Donglei Fan

Lakshmi Iyer, Jr

Jian Song

Yih-Sien Kao

Mustafa Rangwala

Jim Hobza

Rohit Iyer Seshardri

Sarah Xie

Sanjai Bhargava

Michael K Eng

Mark D Redman

Joseph A Santoru

Anthony Noerpel

Rohit Lyer Seshadri

Rohit Lyer Sehadri

Rohit Seshardi

Feng-Wen Sung

Methods, systems, and apparatus for transmodulation in multi-beam satellite communication systems. In some implementations, a gateway receives bitstreams for transmission on different forward links from a satellite to terminals. The gateway is configured to modulate data for transmission on a feeder link for transmissions from the gateway to a satellite, including using a same symbol constellation to modulate data to provide different numbers of bits per symbol. The gateway can be configured to select symbols for transmission from among different subsets of the symbols in the symbol constellation to achieve different numbers of bits per symbol. The gateway can also be configured to select symbols for transmission from among one of the subsets determined based at least in part on a measure of signal strength for the feeder link.

Adaptive constellation for transmodulation in satellite communication systems

A hybrid scanning antenna including: a reflector having a focal line; a first mechanical movement to move the reflector about a first axis; a second mechanical movement to move the reflector about a second axis; a linear array fixedly disposed along the focal line to electronically scan at a scan angle about a third axis; and a controller to control the first mechanical movement, the second mechanical movement and the scan angle of the linear array to orient the hybrid scanning antenna to a look angle of a remote transceiver.

Hybrid scanning antenna

A system and method for recovering from communication interruptions by a periodic blockage. This is achieved by selecting an inner code block rate that supports a Packet Error Ratio (PER) equal to or greater than a target PER during the blockage. An expected number of erasures is estimated and an outer code block rate capable of correcting an erasure ratio is chosen. The input is encoded using the outer code block rate to form an outer code block. One or more inner code blocks are formed by encoding segments of the outer code block using the inner code block rate. These inner code blocks are then transmitted. The count of inner code blocks is greater than 1, and the PER is a ratio of the expected number of erasures to the count of inner code blocks.

Using erasure coding on partial code block communication interruption

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

Various arrangements for improving performance of code split communications are presented herein. A second portion of a first codeword and a third portion of a second codeword can be transmitted using symbols such that each transmitted symbol includes bits from the second portion of the first codeword and bits from the third portion of the second codeword. At a receiver, decoder inputs can be generated for the third portion of the second codeword based on an optimized constellation and the second portion of the first codeword. The second portion of the first codeword is used to identify a label group of the optimized constellation and eliminate all other label groups of the plurality of label groups. Within each label group, symbol labels are Gray labeled. However, at least a first symbol label is not Gray labeled with an adjacent second symbol label of a different label group.

Optimized code-split symbol constellations

A satellite communication system that combines the benefits of Geosynchronous Equatorial Orbit (GEO) and Non-geostationary (NGSO) satellite systems into a GEO-NGSO hybrid satellite system. The hybrid system allows for various uses, such as, a NGSO-GEO-NGSO handoff, a GEO-NGSO-GEO handoff, and/or a multi-transport operation utilizing both the GEO and NGSO satellites. Based on the path delay differences of the GEO and NGSO satellites, the system may create a data buffer to ensure no data loss.

Non-geostationary orbit (NGSO) and geostationary orbit (GEO) hybrid network for uninterrupted communications

A system and method for tracking non-geo synchronous orbit satellites on orbiting planes of regular motion patterns. The method includes providing a first satellites moving in a direction descending in latitude in first orbital planes and a second satellites moving in a direction ascending in latitude in second orbital planes; steering an antenna to an antenna tilt φ from normal with a single axis mechanism lined up with a first axis; scanning, electronically, with a linear array at a scan angle ψ along a second axis; and locking to a signal from a handed-from satellite from the first satellites, where the first axis is angled from the second axis, the steering along the first axis and the scanning along the second axis jointly track the handed-from satellite, the first orbits seem parallel, the second orbits seem parallel, and the first orbits seem aligned with the antenna tilt φ. A handoff between the first satellites may use one of the second satellites as a steppingstone.

Tracking Non-Geo Synchronous Orbit satellites on orbiting planes of regular motion patterns

Methods, systems, and apparatus, including computer programs encoded on computer storage media, for improving adaptive satellite communication. In some implementations, a method includes receiving, by a receiver and from a transmitter, code blocks transmitted according to a first set of parameters that comprises one or more of a first modulation used to transmit the code blocks or a first coding used to encode the code blocks for transmission. A number of corrupted code blocks and a number of parity blocks in a series of the code blocks received are determined. The number of corrupted code blocks are compared with the number of parity blocks. A second set of parameters are determined based on the comparison of the number of corrupted code blocks with the number of parity blocks. The second set of parameters are communicated to the transmitter for subsequent transmissions.

Adaptive satellite communications

A system and method for estimating a geolocation The method includes subdividing the camping cell into grid points where each grid point of the grid points has an associated relative offset from a camping beam center; illuminating the camping cell with a camping beam and each of the adjacent cells with adjacent beams; receiving a camping beam signal strength and adjacent beams signal strengths for each grid point of the grid points; profiling, at each grid point of the grid points, ratios of the camping beam signal strength to each one of the adjacent beams signal strengths; mapping the ratios and the associated relative offset of each grid point of the grid points; and estimating a relative geolocation of a User Terminal (UT) from the camping beam center based on a UT camping beam signal strength and UT adjacent beams signal strengths.

Estimating geolocation of a user terminal

Methods, systems, and apparatus, including computer programs encoded on computer-storage media, for determining a set of communication parameters for receiving data transmissions. In some implementations, a method includes receiving a first data transmission sent according to a first communication parameter scheme that includes at least one of a first modulation or a first coding. A second data transmission is received. A second communication parameter scheme of the second transmission is determined. This determination includes identifying a subset of multiple candidate communication parameter schemes determined based on the first communication parameter scheme, identifying, in the second data transmission, a first identifier that corresponds to the second communication parameter scheme, comparing the first identifier to a respective identifier for each communication parameter scheme in the subset, and determining, as the second communication parameter scheme, a communication parameter scheme in the subset that has an identifier that matches the first identifier.

Efficient adaptive coding and modulation

Various arrangements for a satellite-based forward link overlay are presented herein. In some embodiments, broadband data is modulated at a particular frequency, phase, and/or timing to create a broadband data signal. The frequency, phase, and/or timing are used to modulate a low-bandwidth data signal. The low-bandwidth data signal can then be combined with the broadband data signal and transmitted via satellite to a geographic region. A low-bandwidth receiver unit may determine the frequency, phase, and/or timing from the embedded broadband signal and use such information to demodulate and despread the low-bandwidth data signal.

Overlay of a forward link on broadband satellite signals

A geolocation is estimated by tessellating a coverage area into a camping cell and adjacent cells; subdividing the camping cell into grid points where each grid point of the grid points has an associated relative offset from a camping beam center; illuminating, with a platform, the camping cell with a camping beam and each of the adjacent cells with adjacent beams; receiving a camping beam signal strength and adjacent beams signal strengths for each grid point of the grid points; profiling, at each grid point, ratios of the camping beam signal strength to each one of the adjacent beams signal strengths; mapping the ratios and the associated relative offset of each grid point; and estimating a relative geolocation of a User Terminal (UT) from the camping beam center based on a UT camping beam signal strength and UT adjacent beams signal strengths.

Systems and methods are described, and one method includes allocate a continuous duration within a TDMA scheme, for asynchronous NOMA transmissions, and extending from an allocation start time to an allocation termination time, formed of contiguous time slots of the TDMA scheme, and included providing to asynchronous NOMA user terminals an indication of the allocation start time and termination time, indicating allowance to perform asynchronous NOMA transmissions within a start time constraint that starts of the asynchronous NOMA transmissions do not precede the allocation start time, and terminations of the asynchronous NOMA transmissions do not succeed the allocation termination time.

Asynchronous non-orthogonal multiple access in a time/frequency division orthogonal multiple access network

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Potomac, MD, United States of America

Lin-Nan Lee