A method performed by a ground station antenna system for tracking a non-Geo satellite. A signal is received from the satellite and a signal quality metric associated with the signal is estimated. A first tracking mode is selected and implemented when the estimated signal quality metric is below a threshold, in which the signal is demodulated to obtain demodulated signal quality metric (DSQM) estimates, and then a first tracking operation is performed to point an antenna beam at the satellite based on the DSQM estimates. A second tracking mode is selected and implemented when the estimated signal quality metric is above the threshold, in which signal strength estimates of the signal are obtained and then a second tracking operation is performed to point the antenna beam at the satellite based at least in part on the signal strength estimates.

A low earth orbit (LEO) satellite including a processor, a memory, and a communication sub-system. The communication sub-system including: an antenna array and a reconfigurable digital logic processing device. The processor dynamically reconfigures the reconfigurable digital logic processing device to amplify or attenuate transmissions received from one or more directions of interest, or to amplify or attenuate signals transmitted by the antenna array in one or more directions of interest according to the orbital schedule of the LEO satellite.

A device includes a primary sector and secondary sectors communicatively coupled to the primary sector. The processor included in the primary sector is configured to down convert a Radio Frequency (RF) signals with a first frequency to an analog baseband (IQ) signal with a second frequency, and receive a second digital baseband signal that comprises a first digital baseband signal and a digital echo signal. The first digital baseband signal comprises a training sequence signal. Further, the processor estimates a plurality of filter taps of the FIR filter based on the digital echo signal and estimate the digital echo signal in the received second digital baseband signal based on the first digital baseband signal and the plurality of filter taps of the FIR filter. The estimated digital echo signal is removed from at least one current digital baseband signal based on the down conversion of the RF signals.

Systems and methods for supporting more flexible coverage areas and spatial capacity assignments using satellite communications systems are disclosed. A hub-spoke, bent-pipe satellite communications system includes: terminals; gateways; a controller for specifying data for controlling satellite operations in accordance with a frame definition including timeslots for a frame and defining an allocation of capacity between forward and return traffic. The satellite communications system may employ a satellite with a feed array assembly and may use on-board beamforming or ground-based beamforming. Beam hopping within timeslots of the frame may be used to provide coverage to different cells in different time periods. The flexible coverage areas may be provided using changes in satellite position, antenna patterns, or beam resource allocations.

Systems and methods for partitioned phased array fed (PAFR) antennas with improved throughput capacity are disclosed. The phased array in a PPAFR antenna is partitioned into multiple partitions of antenna elements that can be operated by corresponding beam forming networks with reduce sized, weight, and power consumption characteristics to independently and simultaneously to generate angularly offset static and dynamic spot beams patterns. The independently generated spot beam patterns can be configured to include transmission and receiving spot beams for establishing a number of pathways. Accordingly, the number of pathways a particular partitioned PAFR antenna system can support relative to an unpartitioned PAFR antenna system can be increased while also using smaller and lighter configurations of beam forming networks.

The present invention concerns a method for determining if at least one interferer generated by cross polarization interference is present in a received frame. The method comprises the steps of: —analysing the received frame using a sliding window which analyses at least a part of a first and second planes of the received frame, —determining a factor of merit for each position of the sliding window, —comparing each factor of merit to a threshold in order to determine if at least one interfered zone is present in the received frame, —analysing the factors of merit in order to determine the number of interferers which are present in each interfered zone, —determining the start/end positions of each interferer in the first and second planes of the received frame.

Disclosed embodiments relate satellites using a Software-Defined Radio (“SDR”) system. In one example, a geostationary (GEO) satellite includes an antenna system including multiple antennas, each configured to provide a spot beam having an adjustable throughput for a terrestrial coverage area while the antenna is in an active state and the satellite is in orbit above the Earth, a front-end subsystem communicatively coupled to the antenna system having an input side including an input filter and an analog-to-digital converter, and an output side including an output filter and a digital-to-analog converter, and a software defined radio (“SDR”) communicatively coupled to the antenna system via the front-end subsystem. The SDR, in response to a surge modification request, modifies a throughput of each active antenna by increasing or decreasing a share of a satellite power budget allotted to the antenna by deactivating or activating a previously active or previously inactive antenna, respectively.

A method of receiving a target position and a target orientation of an airborne base station; predicting a target signal quality of the airborne base station at the target position and the target orientation based on at least one previous signal quality of the airborne base station corresponding to at least one previous position and at least one previous orientation of the airborne base station relative to the ground reference. Each previous signal quality of the airborne base station is measured by one or more terrestrial terminals located in corresponding one or more communication beams of the airborne base station. The method further includes selecting a target communication beam among the communication beams of the airborne base station for a communication link.

A user device and method comprising a satellite signal determination module receiving a satellite signal from a satellite comprising a first satellite signal identifier, a memory storing an expected satellite signal identifier for an authorized location of the user device, a comparison module comparing the first satellite signal identifier to the expected satellite signal identifier to identify the first satellite signal as unexpected when the first satellite signal is not the expected satellite signal and a disable module disabling the user device from processing satellite signals in response to comparing.

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.