Signals may be forwarded to a variety of ports for transmission. The signals may be modulated for transmission. The forwarding of signals to ports may be accomplished by forwarding the signals to one or more signal modulators using a processing unit. The mapping of signals to ports may change responsive to a triggering event.

A multiple access slotted wireless communication system comprising a plurality of terminals and a multi-access receiver is described. The multi-access receiver can decode multiple transmissions in each slot of a frame from terminals in its field of view. Each terminal has an active state for transmitting and an inactive state. After receiving acknowledgement of a successful transmission by the terminal, the terminal enters the inactive state for at least a transmission delay time. This may be the remaining time that the terminal is in the field of view of the multi-access receiver. This may be achieved by the terminal using a probability of transmission to determine whether or not to transmit in the next frame. The terminal may also be configured to select the slot in a frame, and this may be based upon information such as which slots were acknowledged. The receiver may use compression to transmit acknowledgement messages.

Systems and methods are described for enabling flexible signal pathways within a satellite of a satellite communications system. For example, a pathway selection subsystem in a bent-pipe satellite enables a flexible arrangement of non-processed signal pathways that couple uplink antenna ports with downlink antenna ports via uplink and downlink pathway selectors. The pathway selectors can be dynamically reconfigured (e.g., on orbit), so that the configuration of the pathway selectors at one time can form one set of signal pathways between respective uplink and downlink antenna ports, and the configuration at another time can form a different set of signal pathways between respective uplink and downlink antenna ports. The pathway selection subsystem can have a simulcast mode which, when active, couples each of at least one of the uplink antenna ports with multiple of the user downlink antenna ports to form one or more simulcast signal pathways.

A wireless communication platform utilizes flexible bandwidth assignment to re-allocate bandwidth between spot beams. The platform may assign a first combination of frequency and polarization (FP) to a first spot beam and a second combination of frequency and polarization to a second spot beam that is adjacent and at least partially overlapping the first spot beam. The platform may assign to the first spot beam a reserved combination of frequency and polarization during a first time period, and at second time, assign the reserved combination to the second spot beam. The platform may also assign the reserved combination simultaneously to adjacent spot beams by managing user of the reserved combination by geographically isolated terminals in the spot beams. The platform may further assign different portions of the reserved combination to adjacent spot beams without geographical limitations.

An active repeater device includes a primary sector and one or more secondary sectors, receives a first beam of input RF signals. A first set of analog baseband signals, are generated based on received first beam of input RF signals. The first set of analog baseband signals are converted to a first set of coded data signals and control information is extracted from the first set of coded data signals by decoding only a header portion of the first set of coded data signals without demodulation of data portion of the first set of coded data signals. Based on the extracted control information, the first set of coded data signals are transmitted as beams of output RF signals to remote user equipment. The transmission is independent of demodulation of the data portion within the active repeater device to reduce latency for transmission of the first set of coded data signals.

An example of a channelizer includes a plurality of receiver circuits, an individual receiver circuit including a frequency demultiplexer that is configured to demultiplex a plurality of subchannels and a time-division demultiplexer coupled to the frequency demultiplexer, the time-division demultiplexer configured to time-division demultiplex the plurality of subchannels to provide a plurality of time-division outputs, an individual time-division output including portions of data from each of the plurality of subchannels; and a plurality of switch circuits, each configured to receive a different time-division output of the plurality of time-division outputs from the individual receiver.

It is presented a method for controlling uplink contribution from a plurality of remote radio heads in a combiner. The method is performed in a remote radio head controller and comprises the steps of: determining a first set of at least one remote radio head; determining a second set of at least one remote radio head, wherein the first set and the second set are disjoint; selecting a first uplink carrier for a first wireless device; selecting a second uplink carrier for a second wireless device; and applying a configuration such that the at least one remote radio head of the first set refrains from contributing on a first channel with uplink signals on the second uplink carrier and that the at least one remote radio head of the second set refrains from contributing on the first channel with uplink signals on the first uplink carrier.

It is presented a method for controlling uplink contribution from a plurality of remote radio heads in a combiner. The method is performed in a remote radio head controller and comprises the steps of: determining a first set of at least one remote radio head; determining a second set of at least one remote radio head, wherein the first set and the second set are disjoint; selecting a first uplink carrier for a first wireless device; selecting a second uplink carrier for a second wireless device; and applying a configuration such that the at least one remote radio head of the first set refrains from contributing on a first channel with uplink signals on the second uplink carrier and that the at least one remote radio head of the second set refrains from contributing on the first channel with uplink signals on the first uplink carrier.

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.

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.