Abstract: Devices, methods, and systems for uplink synchronization in time division multiple access (TDMA) satellite network. In one embodiment, an earth-based satellite terminal is configured to communicate with a satellite hub through a satellite using the TDMA communication protocol. The earth-based satellite terminal is configured to determine its own location, a location of the satellite, estimate a distance between the location of the terminal and the location of the satellite, determine a Coarse Timing Advance based on the distance that is estimated, and transmit data to the satellite based on the Coarse Timing Advance and the TDMA communication protocol. The Coarse Timing Advance may allow uplink TDMA communication without a preamble transmission on a random access channel, the preamble transmission being required in many conventional systems.

Abstract: Devices, systems, and methods for channel access in dynamic spectrum sharing. In one embodiment, a server includes a communication interface, a memory, and an electronic processor configured to receive an allotment of bidding credits, determine an amount of available spectrum, generate a power spectrum matrix, generate a bid based on a need for spectrum access and a portion of the allotment of bidding credits, control the communication interface to transmit the power spectrum matrix and the bid to the one or more servers, receive an external power spectrum matrix and an associated bid from each of the one or more servers, compare the bid to the associated bid to determine a winning bid, and control all of the one or more radio nodes to use the spectrum that is associated with the power spectrum matrix in response to determining that the bid is the winning bid.

Abstract: Devices, methods, and systems with dynamic spectrum sharing. In one embodiment, a wireless communication device includes a software-defined radio, a spectrum sensing sub-system, a memory, and an electronic processor. The software-defined radio is configured to generate an input signal, and wirelessly communicate with one or more radio nodes using a traffic data channel and a broadcast control channel. The spectrum sensing sub-system is configured to sense local spectrum information from the input signal. The electronic processor is communicatively connected to the memory and the spectrum sensing sub-system and is configured to receive the local spectrum information from the spectrum sensing sub-system, receive spectrum information from the one or more radio nodes, and allocate resources for the traffic data channel based on the local spectrum information and the spectrum information that is received from the one or more radio nodes.

Abstract: Methods of transmitting a plurality of communications signals over a plurality of discontiguous bandwidth segments in a frequency band include defining a plurality (NFFT) of orthogonal subcarriers across the frequency band, defining a plurality (N) of available physical subcarriers from among the orthogonal subcarriers. The available physical subcarriers are distributed among, the plurality of discontiguous bandwidth segments. The methods further include spreading the data symbols for each user and combining the spread data symbols to provide composite data signals. The composite data signals are converted to parallel input signals and interleaved. The interleaved signals are assigned to the N available physical subcarriers. Related transmitters, receivers and communications systems are also disclosed.

Abstract: The present invention is drawn to a user equipment for use with a power source and a base station, wherein the power source can provide power. The user equipment includes a transmitting portion and a power source monitoring portion. The transmitting portion can transmit a signal to the base station. The power source monitoring portion can monitor a parameter of the power source and can generate a status signal based at least on the monitored parameter. The transmitting portion can additionally transmit the status signal for receipt by the base station.

Abstract: Satellite communications methods include receiving communications signals including co-channel interference at a space-based component from a plurality of wireless terminals in a satellite footprint over a satellite frequency band and reducing interference in the communication signals by (a) performing co-channel interference reduction on the communications signals to generate a plurality of interference reduced signals and (b) performing multiple access interference cancellation on the interference reduced signals. An interference reducing detector for a satellite communications system includes an interference reducer configured to perform co-channel interference reduction on communications signals to generate a plurality of interference reduced signals, and a detector configured to perform multiple access interference cancellation on the interference reduced signals. Satellite communications systems and satellite gateways including interference reducing detectors are also disclosed.

Abstract: First radio signals are received by a first satellite, the received first radio signals including a desired satellite uplink signal transmitted from a first source using a frequency assigned to the first source and an interfering signal transmitted from a second source using the frequency assigned to the first source. The first radio signals are combined based on a first performance criterion to generate a first output signal. Second radio signals are received by a second satellite, the received second radio signals including a measure of the desired signal. The second radio signals are combined based on a second performance criterion to produce a second output signal. The first and second output signals are combined to generate an estimate of the desired satellite uplink signal.

Abstract: Methods of operating a transceiver including an antenna having a plurality of antenna feed elements are disclosed. The methods include receiving a plurality of samples of a receive signal from the plurality of antenna feed elements, estimating locations of a plurality of signal sources from the plurality of receive signal samples, identifying a plurality of interference sources from among the plurality of signal sources, generating a plurality of antenna feed element weights wM in response to the locations of the interference sources, forming an antenna beam from the antenna to the geographic region using the antenna feed element weights wM, and communicating information over the antenna beam. Related transceivers, satellite gateways and satellites are also disclosed.

Abstract: Methods of transmitting a plurality of communications signals over a plurality of discontiguous bandwidth segments in a frequency band include defining a plurality (NFFT) of orthogonal subcarriers across the frequency band, defining a plurality (N) of available physical subcarriers from among the orthogonal subcarriers. The available physical subcarriers are distributed among, the plurality of discontiguous bandwidth segments. The methods further include spreading the data symbols for each user and combining the spread data symbols to provide composite data signals. The composite data signals are converted to parallel input signals and interleaved. The interleaved signals are assigned to the N available physical subcarriers. Related transmitters, receivers and communications systems are also disclosed.

Abstract: Methods of transmitting a plurality of communications signals over a plurality of discontiguous bandwidth segments in a frequency band include defining a plurality (NFFT) of orthogonal subcarriers across the frequency band, defining a plurality (N) of available physical subcarriers from among the orthogonal subcarriers. The available physical subcarriers are distributed among the plurality of discontiguous bandwidth segments. The methods further include multiplexing the plurality of communications signals onto the plurality of available physical subcarriers. Multiplexing the plurality of communications signals onto the plurality of available physical subcarriers may include assigning the communications signals to respective ones of a plurality (N) of logical subcarriers, and mapping the plurality of logical subcarriers to corresponding ones of the plurality of available physical subcarriers. Related transmitters, receivers and communications systems are also disclosed.

Abstract: A communications system includes a space-based network (SBN) including a plurality of spotbeams using a first set of frequencies and an ancillary terrestrial network (ATN) including a plurality of base stations using a second set of radio frequencies. In a coverage zone of a given spot beam wherein the SBN and the ATN use at least one frequency from the first and second sets of frequencies in common, the SBN uses a narrower bandwidth than the ATN on both forward and return links, the ATN employs frequency spreading on at least its return link communications, the SBN employs spatial beam nulling directed toward at least one ancillary terrestrial component (ATC) of the ATN, the SBN employs forward link margin control, the ATN employs return link power control, the SBN employs return link power control and base stations of the ATN provide isolation in the direction of at least one satellite of the SBN.

Abstract: Methods of forming a downlink beam in an adaptive antenna system of a communications system that may reduce inter-system and/or intra-system interference include receiving vectors of signals including signals transmitted by user terminals of the communications system and signals transmitted by transceivers of an independent communications system, obtaining spatial information for the user terminals of the communications system and the transceivers of the independent communications system, generating complex transmitting weights that form spatial nulls directed at the transceivers of the independent communications system, and transmitting a downlink communications signal using the complex transmitting weights. Related systems are also disclosed.

Abstract: Methods of operating a transceiver including an antenna having a plurality of antenna feed elements are presented. The methods include defining a plurality of antenna gain constraint values gk associated with K geographic constraint points within a geographic region, iteratively generating M antenna feed element weights wM that result in antenna response values fK at the K geographic constraint points based on the corresponding antenna gain constraint values gK, forming an antenna beam from the antenna to the geographic region using the antenna feed element weights wM, and communicating information over the antenna beam. Related transceivers, satellites, and satellite gateways are also disclosed.

Abstract: Methods of forming a beam to a wireless terminal from a transmitter including an antenna having a plurality of antenna feed elements include generating channel estimates at the wireless terminal, obtaining channel phase information from the channel estimates, quantizing the channel phase information to obtain quantized channel phase values, and transmitting the quantized channel phase values to the transmitter. The methods may further include receiving the quantized channel phase values at the transmitter, obtaining channel gain estimates, constructing channel estimates using the quantized channel phase values and the channel gain estimates, and determining transmit beamforming weights in response to the channel estimates. Related transmitters, wireless terminals, and communications systems are also disclosed.

Abstract: Methods of transmitting communications signals from a satellite to a wireless terminal include determining a location of the wireless terminal, selecting a plurality of antenna feed elements at the satellite in response to the determined location of the wireless terminal, block coding a plurality of symbols into a number of transmit streams equal to the number of selected antenna feed elements, and transmitting the transmit streams over the selected plurality of antenna feed elements. Block coding the plurality of symbols may include space-code, space-time and/or space-frequency encoding the plurality of symbols. Related satellites, satellite gateways and satellite communications systems are also disclosed.

Abstract: Methods of transmitting a plurality of communications signals over a plurality of discontiguous bandwidth segments in a frequency band include defining a plurality (NFFT) of orthogonal subcarriers across the frequency band, defining a plurality (N) of available physical subcarriers from among the orthogonal subcarriers. The available physical subcarriers are distributed among the plurality of discontiguous bandwidth segments. The methods further include multiplexing the plurality of communications signals onto the plurality of available physical subcarriers. Multiplexing the plurality of communications signals onto the plurality of available physical subcarriers may include assigning the communications signals to respective ones of a plurality (N) of logical subcarriers, and mapping the plurality of logical subcarriers to corresponding ones of the plurality of available physical subcarriers. Related transmitters, receivers and communications systems are also disclosed.

Abstract: Methods of operating a transceiver including an antenna having a plurality of antenna feed elements are disclosed. The methods include receiving a plurality of samples of a receive signal from the plurality of antenna feed elements, estimating locations of a plurality of signal sources from the plurality of receive signal samples, identifying a plurality of interference sources from among the plurality of signal sources, generating a plurality of antenna feed element weights wM in response to the locations of the interference sources, forming an antenna beam from the antenna to the geographic region using the antenna feed element weights wM, and communicating information over the antenna beam. Related transceivers, satellite gateways and satellites are also disclosed.

Abstract: Methods of forming a downlink beam in an adaptive antenna system of a communications system that may reduce inter-system and/or intra-system interference include receiving vectors of signals including signals transmitted by user terminals of the communications system and signals transmitted by transceivers of an independent communications system, obtaining spatial information for the user terminals of the communications system and the transceivers of the independent communications system, generating complex transmitting weights that form spatial nulls directed at the transceivers of the independent communications system, and transmitting a downlink communications signal using the complex transmitting weights. Related systems are also disclosed.

Abstract: Satellite communications methods include receiving communications signals including co-channel interference at a space-based component from a plurality of wireless terminals in a satellite footprint over a satellite frequency band and reducing interference in the communication signals by (a) performing co-channel interference reduction on the communications signals to generate a plurality of interference reduced signals and (b) performing multiple access interference cancellation on the interference reduced signals. An interference reducing detector for a satellite communications system includes an interference reducer configured to perform co-channel interference reduction on communications signals to generate a plurality of interference reduced signals, and a detector configured to perform multiple access interference cancellation on the interference reduced signals. Satellite communications systems and satellite gateways including interference reducing detectors are also disclosed.

Abstract: Methods of transmitting a plurality of communications signals over a plurality of discontiguous bandwidth segments in a frequency band include defining a plurality (NFFT) of orthogonal subcarriers across the frequency band, defining a plurality (N) of available physical subcarriers from among the orthogonal subcarriers. The available physical subcarriers are distributed among the plurality of discontiguous bandwidth segments. The methods further include multiplexing the plurality of communications signals onto the plurality of available physical subcarriers. Multiplexing the plurality of communications signals onto the plurality of available physical subcarriers may include assigning the communications signals to respective ones of a plurality (N) of logical subcarriers, and mapping the plurality of logical subcarriers to corresponding ones of the plurality of available physical subcarriers. Related transmitters, receivers and communications systems are also disclosed.