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 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 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:
An available signal space, whether it is a priori specified or is cognitively determined based upon an assessment of frequency utilization, serves to provide a number of signal dimensions which may be occupied by a number of pseudo-randomly generated waveforms. The number of pseudo-randomly generated waveforms may be based upon a key input to a pseudo-random number generator and a desired statistical distribution, and may be subjected to an orthogonalization procedure to produce a respective number of orthogonal pseudo-random waveforms which may serve as a communications alphabet. A specific data sequence to be communicated may be associated with a respective specific element/member of the orthogonal pseudo-random waveforms and that specific element/member may be transmitted in lieu of the specific data sequence. Systems/methods of spread-spectrum communications that are substationally devoid of revealing signatures such as chipping and cyclostationarity are presented, offering increased privacy, reduced detectability and reduced exploitation of communications.
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:
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:
A signal strength that is associated with a first wireless communications channel is detected. Electromagnetic energy is transmitted over the first wireless communications channel in response to the signal strength being sufficiently weak. A determination is made whether a handoff should be made to a second wireless communications channel having a signal that is weaker than a signal of the first wireless communications channel. Related systems and methods are described.
Abstract:
A radioterminal system includes a server that contains a listing of satellite spot beams and registration information for radioterminals. The listing of satellite spot beams includes an association of base stations with each satellite spot beam of the listing of satellite spot beams. Related methods are also provided.
Abstract:
A method of providing communications can be provided by at least one space-based and/or terrestrial component of a first system/operator transmitting/receiving information using spectrum allocated to a second system/operator at an aggregate interference level at a space-based component of the second system/operator that is less than or substantially equal to a predetermined threshold. Related other methods, systems, and radioterminals are also disclosed.