Abstract: A radioterminal includes a wireless communications transceiver, a GPS receiver and a controller. The controller is configured to authorize at least one other radioterminal to receive geographic position information of the radioterminal, to activate the GPS receiver to obtain a measure of a geographic position of the radioterminal and to activate the wireless communications transceiver to transmit the measure of the geographic position of the radioterminal to the at least one other radioterminal that was authorized, responsive to a rate of change of position of the radioterminal. Related methods also are described.

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: Beamforming methods for operating a transceiver including an antenna having a plurality of antenna feed elements include defining a plurality of real valued antenna gain constraint values associated with a plurality of geographic constraint points within a geographic region, and generating complex valued antenna feed element weights that result in complex antenna gain values at the geographic constraint points based on the corresponding real valued antenna gain constraint values. An antenna beam is formed from the antenna to the geographic region using the complex valued antenna feed element weights, and information is transmitted over the antenna beam.

Abstract: Communications of a mobile station with a satellite mobile communications system and a terrestrial mobile communications system are coordinated. The mobile station is registered with the terrestrial mobile communications system and, responsive to the registration of the mobile station with the terrestrial mobile communications system, the mobile station is concurrently registered with the satellite mobile communications system. The concurrent registration may include implicitly registering the mobile station with the satellite mobile communications system, e.g., by storing information identifying the mobile station may be stored in a location register of the satellite mobile communications system responsive to the registration of the mobile station with the terrestrial mobile communications system, and maintaining synchronization between the two registrations. Authentication tokens may be pre-generated for quick re-registration with a satellite mobile communications system.

Abstract: Methods of reducing interference in a satellite communications system may include receiving a plurality of feeder link signals and time aligning the plurality of feeder link signals to provide time aligned feeder link signals. At least two of the time aligned feeder link signals may be combined to provide reduced interference of at least one of the feeder link signals. Related systems are also discussed.

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 transmitting an information signal in a satellite communications system include splitting the information signal into a first signal component and a second signal component, transmitting the first signal component to a first system element of the satellite communications system, transmitting the second signal component to a second system element of the satellite communications system, combining the first signal component and the second signal component to form a combined signal, and recovering the information signal from the combined signal. Related systems and components are also disclosed.

Abstract: Methods of reducing interference in a satellite communications system may include receiving a plurality of feeder link signals and time aligning the plurality of feeder link signals to provide time aligned feeder link signals. At least two of the time aligned feeder link signals may be combined to provide reduced interference of at least one of the feeder link signals. Related systems are also discussed.

Abstract: A first and/or a second communications system may provide communications service over a geographic area. A method of operating the first and/or the second communications systems may include generating a measure of aggregate interference reaching a satellite of the second communications system substantially from devices of the first communications system. The measure of aggregate interference reaching the satellite of the second communications system may be transmitted to an element of the first communications system.

Abstract: Methods are provided for predicting uplink interference potential to a mobile satellite system (MSS) generated by ancillary terrestrial components (ATCs) of an ancillary terrestrial network (ATN) and/or ATC radioterminals that are configured to terrestrially use/reuse satellite frequencies that are used and/or authorized for use by a MSS. The methods include measuring power transmitted by and/or received at one or more radioterminals communicating with one or more terrestrial networks and/or transmitted by and/or received at the one or more terrestrial networks communicating with the one or more radioterminals using terrestrial frequencies that are at least partially outside a range of the satellite frequencies. Uplink interference potential to the MSS generated by terrestrial use/reuse of satellite frequencies by the ATN and/or the ATC radioterminals is predicted responsive to the measured power. Related ancillary terrestrial networks are also described.

Abstract: A satellite radioterminal communications system may include first and second space-based components and a return link diversity combiner. The first space-based component may be configured to communicate uni-directionally and/or bidirectionally with a first radioterminal over a first forward link using a first band of frequencies and/or over a first return link using a second band of frequencies. The second space-based component may be configured to communicate uni-directionally and/or bidirectionally with a second radioterminal over a second forward link using a third band of frequencies and/or over a second return link using a fourth band of frequencies. The second space-based component may also be configured to receive return link communications from the first radioterminal over the first return link using the second band of frequencies, and the first and third bands of frequencies may be different bands of frequencies.

Abstract: Two satellite communications systems can use the same frequency or frequencies in geographically overlapping footprints, without creating undue interference in a given system that is caused by the same frequency signal(s) that is/are used by the other system. In particular, an aggregate Effective Isotropic Radiated Power (EIRP) of the radioterminals and/or ancillary terrestrial components of a second satellite communications system in the common footprint is sufficiently low, and/or the receive antenna gain of a first satellite communications system is sufficiently low compared to the receive antenna gain of the second satellite communications system, so as to increase an aggregate receiver noise that is seen by the first satellite system receivers by an amount that does not substantially change a Quality of Service (QoS) of the first satellite communications system.

Abstract: Communications are conducted between a space-based component of the wireless communications system and radioterminals using a plurality of forward link cells and a plurality of return link cells, the return link cells having a greater number of cells per frequency reuse cluster than the forward link cells. At least some of the forward and return link cells may use at least some frequencies of a terrestrial wireless communications system having an adjacent and/or overlapping coverage area. Forward links of the at least some of the forward and return link cells may have a greater link bandwidth than return links of the at least some of the forward and return link cells.

Abstract: A cellular communications system comprising a space based system comprising a first set of cells, and a ground based system comprising a second set of cells. The space and ground systems can optionally function substantially autonomously, with each using spectrum from at least one predetermined frequency band.

Abstract: A signal is received at a component of the wireless CDMA communications system, such as a base station or satellite gateway. A plurality of data sets is generated from the received signal, respective ones of the plurality of data sets corresponding to respective access probes received, for example, over the reverse access channel (R-ACH) or reverse enhanced access channel (R-EACH). At least some of the plurality of data sets are jointly decoded to recover an access probe payload.

Abstract: A wireless communications system includes a space-based component (SBC) and an ancillary terrestrial component (ATC) configured to communicate with radioterminals using a common satellite service link frequency band and respective first and second different sets of channel separation codes. The first and second sets of channel separation codes may include, for example, respective sets of scrambling codes, respective sets of frequency assignment codes, respective sets of channel assignment codes, respective sets of sub-channel assignment codes and/or respective sets of spreading codes.

Abstract: Methods of reducing interference in a satellite communications system may include receiving a plurality of feeder link signals and time aligning the plurality of feeder link signals to provide time aligned feeder link signals. At least two of the time aligned feeder link signals may be combined to provide reduced interference of at least one of the feeder link signals. Related systems are also discussed.

Abstract: A satellite radiotelephone frequency band can be reused terrestrially by an ancillary terrestrial network even within the same satellite cell, using interference reduction/cancellation techniques. An interference reducer is responsive to a space-based component and to an ancillary terrestrial network. The interference reducer is configured to reduce interference in wireless communications that are received by the space-based component from first radiotelephones in the satellite footprint over a satellite radiotelephone frequency band using wireless communications that are received by the ancillary terrestrial network from selected ones of second radiotelephones in the satellite footprint over the satellite radiotelephone frequency band and/or wireless communications that are transmitted by the ancillary terrestrial network to the second radiotelephones in the satellite footprint over the satellite radiotelephone frequency band.

Abstract: A satellite radiotelephone system can include a space-based component and a plurality of ancillary terrestrial components. The space-based component is configured to provide wireless radiotelephone communications over a satellite radiotelephone frequency band. The plurality of ancillary terrestrial components are configured to terrestrially reuse at least one of the satellite radiotelephone frequencies, at least some of the ancillary terrestrial components terrestrially reusing the at least one of the satellite radiotelephone frequencies in a staggered sectorization. Related methods are also discussed.

Abstract: A satellite gateway is coupled to a communications network and is operative to communicate with a communications satellite. A terrestrial terminal interface subsystem is operative to communicate with the satellite gateway via the communications satellite using a first radio interface and to communicate with terminals over a geographic area using a second radio interface. The communications network may be a wireless communications network, and the satellite gateway is configured to communicate with a base station controller of the wireless communications network, such that the terrestrial terminal interface subsystem may provide one or more satellite-linked terrestrial base stations.