Abstract: A constellation of non-geosynchronous satellites are in a common orbit. Each time one of the satellites is at a trigger location, a new rolling wave of handovers is started that includes performing handovers of a group of dependent spot beams between adjacent satellites in sequence for pairs of adjacent satellites in a single direction around the orbit.

Abstract: Described herein is a space based subsystem of a satellite, and methods for use therewith, for receiving an RF uplink feeder beam and in dependence thereon producing one or more optical ISL beams for transmission to one or more other satellites. The subsystem can include an antenna to receive an RF feeder uplink beam and produce an RF signal therefrom. The subsystem can also include, inter alia, RF components, local oscillator(s), lasers, EOMs, a WDM multiplexer, an optical amplifier and transmitter optics. Such components can be used to convert the RF signal to one or more ISL beams for transmission to one or more other satellites. Where RF frequencies of optical data signals output by the EOMs are within the same RF frequency range within which the other satellite(s) transmit RF service downlink beams, there is an elimination of any need for the other satellite(s) to perform frequency conversions.

Abstract: This disclosure provides systems, methods and apparatus for digital beamforming. In one aspect, a subsystem of a spacecraft can include multipliers and a data distribution network including adders to provide beamformed signals.

Abstract: Described herein are space based subsystems of a satellite, and related methods, for use in producing an optical feeder downlink beam in dependence on RF service uplink beams received from service terminals within a specified RF frequency range. Beneficially certain embodiments eliminate the need for any type of frequency conversion equipment in the spaced based subsystem that is used to produce the optical feeder downlink beam. Also described herein are ground based subsystems, and related methods, for use in transmitting an optical feeder uplink beam to a satellite configured to receive the optical feeder uplink beam and in dependence thereon produce and transmit a plurality of RF service downlink beams within a specified RF frequency range to service terminals. Also described herein is are space based subsystems of a satellite, and related methods, for use in transmitting a plurality of RF service downlink beams to service terminals.

Abstract: Described herein are ground based subsystems, and related methods, for use in transmitting an optical feeder uplink beam to a satellite that includes a multiple element antenna feed array and that is configured to accept the optical feeder uplink beam and in dependence thereon use the multiple element antenna feed array to produce and transmit a plurality of radio frequency (RF) service downlink beams to service terminals. Certain embodiments are related to a ground based beamformer (GBBF) for inclusion in a ground based subsystem, and methods for use therewith. Beneficially, embodiments described herein allow for flexible antenna beam forming for large signal bandwidth without the limitation associated with the available gateway uplink and downlink spectrum at RF frequencies. Also described herein are space based subsystems for use with such ground based subsystems.

Abstract: A communication platform (e.g., a flexible satellite) includes electrical to optical converters configured to convert input electrical signals to input optical signals, an optical switching network connected to the electrical to optical converters that choose which input optical signals to route to which output beams, tunable optical filters (connected to the switching network) that are configured to select programmable sub-bands of the input optical signals to create output optical signals, and optical to electrical converters (connected to the tunable optical filters) that are configured to convert the output optical signals to output electrical signals for the output beams.

Abstract: A spacecraft operating in a low earth orbit having an altitude in the range of 160 to 800 km has a main body that includes heat dissipating electrical equipment and an earth-facing payload. Control surfaces on the spacecraft are articulated so as to: provide three-axis attitude control to the spacecraft main body using aerodynamic drag effects, such that the earth-facing payload is maintained in a selected orientation with respect to the earth; and control one or both of orbit altitude and period by articulating the control surfaces so as to regulate an amount of aerodynamic drag. The control surfaces include a first control surface disposed, in an on-orbit configuration, on a boom, the boom being mechanically coupled with the main body, and with one or both of a solar array electrically coupled with the electrical equipment and a thermal radiating array thermally coupled with the electrical equipment.

Abstract: Described herein are ground based subsystems, and related methods, for use in transmitting an optical feeder uplink beam to a satellite that is configured to receive the optical feeder uplink beam and in dependence thereon produce and transmit a plurality of RF service downlink beams within a specified RF frequency range to service terminals. Also described herein are space based subsystems of a satellite, and related methods, for use in transmitting a plurality of RF service downlink beams within a specified RF frequency range to service terminals. Beneficially certain embodiments eliminate the satellite to perform any RF frequency conversions upstream of a channelizer of the space based forward link subsystem on the satellite. Also described herein is space segment return link equipment, and related methods, for use in transmitting an optical feeder downlink beam to a ground based subsystem, as well as ground based return link equipment thereof.

Abstract: A constellation of satellites form a communication system that includes communication between satellites and ground terminals as well as communication between satellites. The inter-satellite communication is implemented via wireless network comprising a first set of rings in a first orientation and a second set of rings in a second orientation. Each ring of the first set of rings and the second set of rings comprises two ringlets transmitting in opposite directions. Each satellite of the plurality of satellites is configured to communicate in a ring of the first set of rings and communicate in a ring of the second set of rings.

Abstract: A spacecraft including a main body structure and at least a first deployable element is reconfigured from a launch configuration to an on-orbit configuration. In the launch configuration, the first deployable element is mechanically attached with the spacecraft main body structure by way of a first arrangement. In the on-orbit configuration, the first deployable element is mechanically attached with the spacecraft main body structure by way of a second arrangement. Reconfiguring the spacecraft includes detaching the first deployable element from the first arrangement, moving the first deployable element with respect to the spacecraft main body structure; and attaching the first deployable element to the second arrangement.

Abstract: Described herein are ground based subsystems, and related methods, for use in transmitting an optical feeder uplink beam to a satellite that is configured to receive the optical feeder uplink beam and in dependence thereon produce and transmit a plurality of RF service downlink beams within a specified RF frequency range to service terminals. Certain embodiments are related to a resource allocator for inclusion in a ground based subsystem, and methods for use therewith. Beneficially, the resource allocator, and methods for use therewith, eliminate any need for a satellite to perform any bandwidth allocation for the plurality of service downlink beams produced and transmitted by the satellite, thereby eliminating any need for the satellite to include an on-board channelizer. Such a recourse allocator can include a plurality of channels each of which can include an encoder and modulator, a channel filter, and a frequency up-converter.

Abstract: Described herein is a space based subsystem of a satellite, and methods for use therewith, for receiving an RF uplink feeder beam and in dependence thereon producing one or more optical ISL beams for transmission to one or more other satellites. The subsystem can include an antenna to receive an RF feeder uplink beam and produce an RF signal therefrom. The subsystem can also include, inter alia, RF components, local oscillator(s), lasers, EOMs, a WDM multiplexer, an optical amplifier and transmitter optics. Such components can be used to convert the RF signal to one or more ISL beams for transmission to one or more other satellites. Where RF frequencies of optical data signals output by the EOMs are within the same RF frequency range within which the other satellite(s) transmit RF service downlink beams, there is an elimination of any need for the other satellite(s) to perform frequency conversions.

Abstract: Described herein is a space based subsystem of a satellite, and methods for use therewith, for producing and transmitting an optical ISL beam to another satellite. The subsystem can include, inter alia, receiver optics, optical amplifiers, a WDM demultiplexer, beam splitters, a WDM multiplexer, and transmitter optics. The transmitter optics may be configured to receive an amplified wavelength division multiplexed optical signal and, in dependence thereon, transmit an optical ISL beam to another satellite. In certain embodiments, because RF frequencies of a wavelength division multiplexed optical signal produced by the WDM multiplexer are within a same specified RF frequency range within which the other satellite is configured to transmit RF service downlink beams, there is an elimination of any need for the other satellite to perform any frequency conversions when producing the RF service downlink beams in dependence on the optical ISL beam.

Abstract: Described herein is a space based subsystem of a satellite, and methods for use therewith, for receiving an optical ISL beam from another satellite, and in dependence therein, producing a further optical ISL beam for transmission to a further satellite. Additionally, the subsystem can also produce RF service downlink beams for transmission to service terminals. The subsystem can include, inter alia, receiver optics, optical amplifiers, a WDM demultiplexer, beam splitters, a WDM multiplexer, and transmitter optics. In certain embodiments, because RF frequencies of a wavelength division multiplexed optical signal produced by the WDM multiplexer are within a same specified RF frequency range within which the satellite and the further satellite are configured to transmit RF service downlink beams, there is an elimination of any need for the satellite and further satellite to perform any frequency conversions when producing the RF service downlink beams in dependence on the optical ISL beams.

Abstract: A satellite communications system provides for handovers between spot beams, including communicating (at a ground based terminal) with a non-geostationary satellite constellation using a first spot beam of the non-geostationary satellite constellation and a first beam hopping plan. The ground based terminal changes the communicating with the non-geostationary satellite constellation to use a second spot beam of the non-geostationary satellite constellation and a second beam hopping plan.

Abstract: A satellite communication system comprises a satellite configured to provide a plurality of spot beams adapted for communication using time domain beam hopping to switch throughput among spot beams of the plurality of spot beams. The plurality of spot beams includes a first spot beam that illuminates and communicates with a first gateway and a first set of subscriber terminals. The satellite is configured to implement a beam hopping plan that during a hopping period provides throughput to the first spot beam for an aggregated time duration based on bandwidth assignments to the first gateway and the first set of subscriber terminals.

Abstract: A satellite communication system comprises one or more non-geostationary satellites. Each satellite is configured to provide a plurality of spot beams.

Abstract: A satellite communication system includes a non-geostationary satellite configured to provide a first plurality of non-articulated spot beams that comprise a Field of Regard. The satellite further configured to provide a steerable spot beam that can be steered to establish communication with a gateway outside and in front of the Field of Regard and maintain communication while the satellite and the Field of Regard moves over and past the gateway including after the gateway is outside of and behind the Field of Regard.

Abstract: A satellite communication system provides for handovers between satellites and multiple gateways. Terminals communicate with a first gateway via a first satellite as beams of the first satellite traverse the region. A second gateway is in communication with the first satellite and hands over to a second satellite. The first gateway is at a first location. The second gateway is at a second location separated from the first location in the orbital direction. Terminals handover to the second satellite as beams of the second satellite begin to traverse the region, and the terminals start connecting to and communicating with the second gateway via the second satellite. After all of the terminals of the plurality of terminals handover to the second satellite, the first gateway hands over to the second satellite and then the terminals in the region communicate with the first gateway via the second satellite.

Abstract: A satellite communication system includes a satellite configured to provide a first plurality of spot beams adapted for communication with subscriber terminals using time domain beam hopping and a second plurality of spot beams adapted for communication with gateways. The satellite includes a spectrum routing network that is configured to time multiplex spot beams of the second plurality of spot beams with spot beams of the first plurality of spot beams so that a spot beam that is implementing beam hopping for communication to subscriber terminals communicates with different feeder beams (and, therefore, different gateways) at different times during a hopping period.