Patent ID: 6275480
Filing Date: 2001-08-14
Classification: H04B

Abstract:
A spacecraft TDMA cellular communication system, for communicating traffic signals between disparate terrestrial locations, said system comprising:a spacecraft including transmitting and receiving means, and an antenna arrangement coupled to said transmitting and receiving means, for forming a plurality of spot beams, each of which defines a footprint, which footprints of said spot beams may partially overlap;a plurality of terrestrial terminals, some of which may be mobile user terminals, at least some of which are coupled to receive information signals, and for encoding said information signals for transmission over said communication system, said information signals being encoded into frames of constant duration, each frame of which contains a particular number of bits, which number of bits remains the same from frame to frame, each of said terrestrial terminals being located in at least one of said footprints, each of said terrestrial terminals being for transmitting electromagnetic signals including said encoded information signals to said spacecraft within a predetermined frequency band, and for receiving electromagnetic signals within a second frequency band, each of said terrestrial terminals further including encoding/decoding means, for encoding control signals to generate encoded control signals including at least call maintenance control signals, which call maintenance control signals are for interrupting said traffic signals, each of said terrestrial terminals encoding said control signals in blocks having the same duration as said duration of said frames of said information signal, and having said particular number of bits;each of said terrestrial terminals also including receiving/decoding means for receiving said encoded information signals and said encoded control signals, for decoding said information signals arriving from another one of said terrestrial terminals by use of a particular decoding algorithm suited for decoding said information signals, and for decoding said control signals using said particular decoding algorithm, whereby said terrestrial terminals need store only said particular decoding algorithm in order to decode both said information signals and said control signals.