Abstract: 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.

Abstract: 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 ? from normal with a single axis mechanism lined up with a first axis; scanning, electronically, with a linear array at a scan angle ? 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 ?. A handoff between the first satellites may use one of the second satellites as a steppingstone.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: Communication terminals, systems and methods are disclosed herein. In an embodiment, a method for improving communication throughput when experiencing periodic blockages includes reading a plurality of data elements into an interleaver in one of a quasi-reverse order and a consecutive order, reading the plurality of data elements out of the interleaver in the other of the quasi-reverse order and the consecutive order, and. transmitting the plurality of data elements via a communication channel that experiences periodic blockages.

Abstract: 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.

Abstract: Communication terminals, systems and methods are disclosed herein. In an embodiment, a method for improving communication throughput when experiencing periodic blockages includes reading a plurality of data elements into an interleaver in one of a quasi-reverse order and a consecutive order, reading the plurality of data elements out of the interleaver in the other of the quasi-reverse order and the consecutive order, and transmitting the plurality of data elements via a communication channel that experiences periodic blockages.

Abstract: 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.

Abstract: Communication terminals, systems and methods are disclosed herein. In an embodiment, a method for improving communication throughput when experiencing periodic blockages includes generating at least one outer code block including a plurality of sync data elements, writing the sync data elements from the at least one outer code block to a same column of at least one interleaver including a plurality of rows and a plurality of columns, and writing additional data elements from the outer code block to other columns of the at least one interleaver.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A system and method for estimating a geolocation. The method includes 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 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.