Abstract: A satellite computer system of a satellite is configured to communicate with user equipment (UE). The satellite includes an antenna configured to communicate with the UE via directional beams that define cells of a radio access network (RAN). The satellite computer system can perform steps that can include one or more of: receiving on a first beam a data stream including an uplink signal from a first UE, wherein the received uplink signal includes a Doppler shift; compensating the received data stream for a reference Doppler shift based on a trajectory of the satellite relative to a cell reference location of the first beam, wherein the reference-location-compensated uplink signal retains a residual Doppler shift; estimating a coarse portion of the residual Doppler shift; estimating a fine portion of the residual Doppler shift; and de-shifting the reference-location-compensated uplink signal by a shift frequency comprising the coarse portion and the fine portion.

Abstract: In one example of the present disclosure, a radome assembly for use with an antenna assembly is described. The radome assembly may comprise a radome body portion having a first side and a second side, wherein the radome body portion defines a portion of a housing for an antenna assembly. The radome assembly may further comprise an outer layer coupled to the first side of the radome body portion, wherein the outer layer is made from a different material than the radome body portion, and wherein at least a portion of the outer layer is exposed to an outdoor environment and has hydrophobic properties.

Abstract: A spacecraft system may include a first spacecraft having a chassis and a first antenna moveably mounted to the chassis, and a second spacecraft having a chassis, wherein the second spacecraft is adjacent the first spacecraft during launch to define a stacked configuration, and a passive restraint system defined between the first and second spacecraft that is configured to substantially prevent movement of the first antenna in a launch position while in a launch state when the first and second spacecraft are in a stacked configuration.

Abstract: Systems, methods, and non-transitory media are provided for timing transmissions in a wireless communication system. An example method can include determining, at a satellite, a maximum round-trip propagation delay associated with one or more user terminals of a plurality of user terminals, determining, based on the maximum round-trip propagation delay, a respective downlink to uplink (DL/UL) offset for each user terminal, wherein the DL/UL offset comprises a time difference between a first downlink frame at the satellite and a first corresponding uplink frame at the satellite, transmitting a first downlink frame, receiving a first uplink frame from a first user terminal associated with the maximum round-trip propagation delay during the first corresponding uplink frame at the satellite, and receiving a second uplink frame from a second user terminal associated with a round-trip propagation delay less than the maximum round-trip propagation delay during the first corresponding uplink frame at the satellite.

Abstract: A satellite computer system is configured to detect access request signals from terrestrial user equipment (UE). The satellite includes an antenna configured to send and receive signals to the UE on a radio access network (RAN) via beams that define cells of the RAN. The satellite computer system can perform steps that can include one or more of: detecting a coarse time offset of one or more access signals embedded in a signal received within a PRACH slot; detecting information identifying a root of a Zadoff-Chu sequence underlying each of the one or more access signals; generating, based on the identified root, potential pairs of frequency and time offset values for the access signals; selecting, based on the detected coarse time offset, one of the potential pairs; and sending, to the UE based on the selected pair, an access response formatted according to the RAN.

Abstract: In accordance with various embodiments of the present disclosure, a radome assembly for use with an antenna assembly includes a radome body portion having a first side and a second side. The radome assembly further includes an outer layer formed from a first material, configured to be coupled to the first side of the radome body portion, and configured to be exposed to an environment of the radome.

Abstract: A user terminal for a satellite communication system is programmed to receive data specifying candidate satellites of a plurality of satellites as being available for links during a plurality of time slots. The user terminal is assigned to a ground network point-of-presence (PoP). The candidate satellites are scheduled to communicate with different ones of a plurality of gateway terminals during each time slot. The user terminal can, during a first time slot, transmit first data requests to one of the candidate satellites; detect a deviation from a communication quality threshold on a communication path between the phased array antenna and the ground network PoP; and in response to the detection, transmit second data requests to another candidate satellite. Additionally or alternatively, the user terminal can proactively avoid a communication interruption related to obstructed lines of sight of a phased array antenna of the user terminal by switching between candidate satellites.

Abstract: In an embodiment, a communications system includes a first transmitter electrically coupled to a first antenna of a phased array antenna, the first transmitter configured to receive an input signal, apply a first baseband frequency shift to the input signal to generate a first baseband frequency shifted input signal, generate a first modulated signal based on the first baseband frequency shifted input signal and transmit the first modulated signal by the first antenna. The communications system includes a second transmitter electrically coupled to a second antenna of the phased array antenna. The second transmitter configured to receive the input signal, apply a second baseband frequency shift, different from the first baseband frequency shift, to the input signal to generate a second baseband frequency shifted input signal, generate a second modulated signal based on the second baseband frequency shifted input signal, and transmit the second modulated signal by the second antenna.

Abstract: A computer system for mapping geographic sub-areas of a ground area to cells of a radio access network (RAN) implemented by a plurality of satellites can perform steps including one or more of: receiving, from a first satellite, connection data indicating that a first UE has connected to the RAN via a first beam of the first satellite, wherein the connection data identifies a physical localized identifier of the first beam and a connection time; determining, from a mapping of physical localized identifiers to virtual localized identifiers across a plurality of time slots, a first virtual localized identifier associated with the physical localized identifier of the first beam and the connection time, the first virtual localized identifier corresponding to a first of the geographic sub-areas; and, in response to the determining, causing to be stored location data for the first UE indicative of the first geographic sub-area.

Abstract: In an embodiment, an apparatus includes one or more electrical components. The one or more electrical components are configured to encode each data beam of a first plurality of data beams of a first channel to generate an encoded first plurality of data beams. The one or more electrical components are configured to encode each data beam of a second plurality of data beams of a second channel to generate an encoded second plurality of data beams. The one or more electrical components are configured to generate a combined channel comprising an aggregation of at least a portion of the encoded first plurality of data beams and at least a portion of the encoded second plurality of data beams.

Abstract: Systems and methods for using the shield of a cable for communication are disclosed. An example system includes a first electronic device, a second electronic device and a cable coupled to the first electronic device and to the second electronic device and having a conductive material independent of at least one communication line. The first electronic device and the second electronic device can be configured to communicate using a first communication protocol via the at least one communication line and using a second communication protocol via the conductive material. Communications using the second communication protocol can include a feedback signal to indicate a status of at least one of the first electronic device or the second electronic device. The first electronic device can be a user terminal configured to communicate wirelessly with a satellite, and the second electronic device can be a router configured to communicate with at least one user device.

Abstract: An integrated signal chain includes a waveguide network defined by first and second waveguide layers forming a waveguide stack. A first transmit waveguide channel (WGC) is configured to communicate first transmit electromagnetic signals from a first transmit port to an antenna feed port, and a first receive WGC is configured to communicate first receive electromagnetic signals from the antenna feed port to a first receive port. A transmit module is attached to an exterior side of the first waveguide layer, and the first transmit WGC couples the transmit module to the antenna. A receive module is attached to the exterior side of the first waveguide layer, and the first receive WGC couples the antenna to the receive module. A modem may be included. A thermal management assembly can be configured to dissipate heat from the modem, the receive module, and/or the transmit module.

Abstract: In one example of the present disclosure, a radome body assembly for use with an antenna assembly is described. The radome body assembly may comprise a radome body portion having a first surface and a second surface, wherein the second surface is opposite the first surface, and wherein the radome body portion defines a portion of a housing for an antenna assembly. The radome body assembly may further comprise a plurality of elongated members each coupled to the second surface of the radome body portion and each having a proximal end at or near the radome body portion and a distal end distal from the radome body portion, wherein the plurality of elongated members is configured to extend through a plurality of corresponding thru-holes defined in the antenna assembly.

Abstract: A calibration system includes a beamformer lattice including at least a first beamformer, the first beamformer corresponding to a first subset of antenna cells of a plurality of antenna cells including a plurality of feed lines extending between the first beamformer and each of the first subset of antenna cells, and the first beamformer including a first calibration section for comparing a reference signal to a non-reference signal; and a first calibration line corresponding with the first beamformer, wherein the first calibration line is configured to deliver a first reference signal (mTx) from the first beamformer to be received by a first antenna feed line for comparison with a first non-reference signal (Rx) in the first beamformer, and/or wherein the first calibration line is configured to deliver a second non-reference signal (Tx) from a second antenna feed line for comparison with a second reference signal (mRx) in the first beamformer.

Abstract: Systems, methods, and non-transitory media are provided for low latency handovers. An example method can include receiving, by a user terminal associated with a cell served by a satellite, a schedule of communications between the user terminal and one or more satellites, wherein the one or more satellites comprises the satellite and a different satellite, and wherein the schedule of communications is obtained by the user terminal from the satellite; requesting, based on the schedule, a handover from a beam of the satellite to a different beam of one of the satellite or the different satellite; performing the handover from the beam of the satellite to the different beam of the one of the satellite or the different satellite; and after the handover, transmitting, by the user terminal, one or more packets via the different beam of the one of the satellite or the different satellite.

Abstract: A method for downlink link adaptation includes receiving, from a satellite and at a user terminal, a first data packet data unit according to a first downlink modulation and coding scheme (MCS), computing error vector magnitude data associated with the first data packet data unit, generating, based on one or more of the error vector magnitude data, user terminal signal-to-noise-ratio feedback based on a constant times a previous user terminal signal-to-noise-ratio and a current user terminal signal-to-noise-ratio, and transmitting an uplink packet data unit having a downlink block error rate and the user terminal signal-to-noise-ratio feedback. A satellite runs a link adaptation algorithm based on the user terminal signal-to-noise-ratio feedback and block error rate to generate a second downlink MCS. The method includes receiving at the user terminal a second data packet data unit according to the second downlink MCS for the satellite-to-user-terminal downlink. Uplink link adaptation is also disclosed.