摘要:
Space-based wireless radiotelephone communications are provided in a satellite footprint over a satellite radiotelephone frequency band. The satellite footprint is divided into satellite cells in which satellite radiotelephone frequencies of the satellite radiotelephone frequency band are spatially reused. At least one of the satellite radiotelephone frequencies that is assigned to a given satellite cell in the satellite footprint is terrestrially reused outside the given satellite cell. A radiation pattern of at least the given satellite cell is modified to reduce interference with the at least one of the satellite radiotelephone frequencies that is terrestrially reused outside the given satellite cell.
摘要:
A space-based network for a satellite radiotelephone system includes at least one receive-only satellite and at least one transmit satellite. The transmit satellite can be a transmit-only satellite or a transmit and receive satellite. The receive-only satellite(s) are configured to receive wireless communications from a radiotelephone at a location over a satellite frequency band. The transmit satellite(s) are configured to transmit wireless communications to the radiotelephone at the location over the satellite frequency band. By providing at least one receive-only satellite and at least one transmit satellite, space-based networks can offer a significant link margin, without the need to undesirably burden the radiotelephones themselves to achieve this link margin.
摘要:
A satellite communications system includes a satellite that is configured to wirelessly communicate with radioterminals in a satellite coverage area over a satellite frequency band, and an ancillary terrestrial component that is configured to wirelessly communicate with radioterminals in the satellite coverage area over at least some of the satellite frequency band, to thereby terrestrially reuse at least some of the satellite frequency band. Wireless communications with a radioterminal are handed over from the ancillary terrestrial component to the satellite if the radioterminal transmit power exceeds a threshold, and a received satellite signal quality exceeds a threshold, even though the radioterminal is able to wirelessly communicate with the ancillary terrestrial component. Downlink wireless radiation that is received at the radioterminal from a satellite may be monitored to determine potential interference created by the uplink radiation of the radioterminal due to the terrestrial reuse of at least some of the satellite frequency band.
摘要:
A mobile radiotelephone terminal having a satellite radiotelephone and a Global Positioning System (GPS) obtains a coarse position of the mobile radiotelephone terminal from satellite radiotelephone system communications. The GPS receiver uses the coarse position to determine an accurate position of the mobile radiotelephone terminal. Accordingly, by obtaining a coarse position from the satellite radiotelephone systems communications, the computation time for the GPS receiver to compute an accurate position of the mobile radiotelephone terminal may be reduced. By allowing a reduction of computation time by the GPS receiver, an accurate position may be obtained more quickly and/or with reduced power.
摘要:
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.
摘要:
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.
摘要:
A satellite radiotelephone system includes a space-based component, a plurality of ancillary terrestrial components, and a plurality of radiotelephones. The space-based component is configured to provide wireless radiotelephone communications using satellite radiotelephone frequencies. The plurality of ancillary terrestrial components include a plurality of ancillary terrestrial component antennas configured to provide wireless radiotelephone communications using at least one of the satellite radiotelephone frequencies in a radiation pattern that increases radiation below the horizon compared to above the horizon. The plurality of radiotelephones are configured to communicate with the space-based component and with the plurality of ancillary terrestrial components. Each radiotelephone also includes a GPS signal processor and a GPS mode filter that is configured to suppress energy at (1575.42−&Dgr;) MHz, where 0
摘要:
The fade character of a received double-sideband, phase coherent signal is determined from the location of the fade notch frequency, (.omega..sub.F) relative to the center (.omega..sub.c) of the received signal frequency spectrum and the phase between fundamental components of first (P.sub.1) and second (P.sub.2) product signals. These product signals are derived (401, 403, 411, 413, 419, 420, 421 or 801, 802, 803, 805, 811) using first (.omega..sub.1) and second (.omega..sub.2) spectral components that are symmetrically disposed about the center of the received signal frequency spectrum. The fundamental components of each product signal are at a common frequency.
摘要:
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.
摘要:
Systems and/or Methods are disclosed for acquiring data from a transceiver responsive to one or more signals that are received at the transceiver from one or more devices. In one embodiment, a transceiver is configured to transmit a signal responsive to having received a first signal from a first device, wherein the signal that is transmitted by the transceiver is configured to trigger a second device to transmit a second signal. The transceiver is further configured to transmit data responsive to having received the second signal that is transmitted by the second device. In other embodiments, a transceiver is configured to receive a signal from a first device over frequencies of a predetermined frequency band that the first device is authorized to use, to receive a signal from a second device over frequencies of the predetermined frequency band and to transmit data responsive to having received both the signal from the first device and the signal from the second device. The transceiver is further configured to require that both the signal from the first device and the signal from the second device be received at the transceiver before the data is transmitted. Analogous methods are also disclosed.