Broadband satellite communications systems using optical feeder links are disclosed. Various optical modulation schemes are disclosed that can provide improved capacity for fixed spot beam, on board beamforming, and ground-based beamforming broadband satellite systems.

A control method and a control device in a heterogeneous three-dimensional hierarchical network, and a communication system are provided. The control method includes: obtaining a coverage mode of a terminal; when the coverage mode is single-layered sub-network coverage, setting a non-ground mobile communication sub-network or a ground mobile communication sub-network corresponding to the single-layered sub-network coverage to be in a standalone operating mode or an intra-layer carrier aggregation mode; and when the coverage mode is multi-layered sub-network coverage, setting the non-ground mobile communication sub-network corresponding to the multi-layered sub-network coverage, or the ground mobile communication sub-network and the non-ground mobile communication sub-network corresponding to the multi-layered sub-network coverage, to be in a cross-layer carrier aggregation mode. The ground mobile communication sub-network and the non-ground mobile communication sub-network use a same or unified radio access technology.

Systems and methods for controlling satellites are provided. In one example embodiment, a computing system can obtain a request for image data. The request can be associated with a priority for acquiring the image data. The computing system can determine an availability of a plurality of satellites to acquire the image data based at least in part on the request. The computing system can select from among a plurality of communication pathways to transmit an image acquisition command to a satellite based at least in part on the request priority. The plurality of communication pathways can include a communication pathway via which the image acquisition command is indirectly communicated to the satellite via a geostationary satellite. The computing system can send the image acquisition command to the selected satellite via the selected communication pathway.

Examples disclosed herein relate to a phased array antenna system for use with a Low Earth Orbit (“LEO”) satellite constellation. The phased array antenna system has a plurality of antenna panels positioned in a dome and an antenna controller to control the plurality of antenna panels, the controller directing a first antenna panel to transmit a first signal and a second antenna panel to transmit a second signal to a LEO satellite, the first signal having a first phase and the second signal having a second phase different from the first phase.

Methods and apparatus are disclosed for uplink power control of a terminal in a satellite communication system. Calibration data that includes output backoff values corresponding to input backoff values for each of a first set of calibration frequencies is initially stored in the terminal. A normalized transmit power for the terminal is determined for multiple transmit frequencies based on the calibration data. Upon receiving an assigned frequency for communicating, the terminal selects one of the normalized transmit power previously determined and begins transmitting.

A method for satellite communication over non-geosynchronous orbit (NGSO) satellites, using a terminal having a non-tracking antenna, is presented. The terminal may communicate with an NGSO satellite each time the NGSO satellite passes through the terminal's antenna beam (communication opportunity). Though the communication opportunities are short and may reoccur at relatively long intervals (e.g., minutes to tens of minutes), these communication opportunities may be sufficient for transmitting the volumes of information generated by Internet of Things (IoT) applications during the intervals between communication opportunities.

Modular antennas with high instantaneous bandwidth are described. In one embodiment, an antenna comprises a plurality of antenna modules tiled together and configured to form one metasurface antenna with an array of surface scattering metamaterial antenna elements; and a feed network comprising a plurality of feed points coupled to the plurality of antenna modules to supply the modules with a feed wave.

A MIMO basestation for a cellular communications system comprises a remote indoor processing facility coupled to an outdoor RF tower via optical fibers. The remote indoor processing facility includes a bank of RF modulators to modulate signal streams; a remote MIMO transmitting processor that includes a remote digital beam-forming network to transform the modulated signal streams into transmit beam signals; a pre-processor to perform a wavefront multiplexing transform on the transmit beam signals to generate wavefront multiplexed beam signals, each of the wavefront multiplexed beam signals being a linear combination of the transmit beam signals; and RF-to-optical drivers to perform optical modulating functions on the wavefront multiplexed beam signals to generate optical waveform streams.

Various arrangements for increasing a transfer rate of a data transfer via satellite are presented. A satellite gateway may set an accelerated set of communication parameters that control communication between the satellite gateway and the satellite terminal via the satellite and between the satellite gateway and the content source to an accelerated transfer rate between the content source and the satellite terminal. A first set of data may be transferred from the content source to the satellite terminal using the set of communication parameters. After transferring the first set of data, the satellite gateway may adjust the initial set of communication parameters to an adjusted set of communication parameters. The adjusted transfer rate can be lower than the accelerated transfer rate.

Methods and systems are described for providing end-to-end beamforming. For example, end-to-end beamforming systems include end-to-end relays and ground networks to provide communications to user terminals located in user beam coverage areas. The ground segment can include geographically distributed access nodes and a central processing system. Return uplink signals, transmitted from the user terminals, have multipath induced by a plurality of receive/transmit signal paths in the end to end relay and are relayed to the ground network. The ground network, using beamformers, recovers user data streams transmitted by the user terminals from return downlink signals. The ground network, using beamformers generates forward uplink signals from appropriately weighted combinations of user data streams that, after relay by the end-end-end relay, produce forward downlink signals that combine to form user beams.