Patent ID: 6963544

Claim:
A frequency division duplex point-to-multipoint communications system that divides a frequency allocation into two bands, a downlink band that carries communications from a central station to multiple stations, and an uplink band that carries communications from multiple stations to the central station, the system comprising: a carrier generator generating a plurality of carriers within each of said bands, each of said carriers being in a spaced relationship to the other carriers such that each said band is sub-divided into a plurality of sub-bands that are equal in number to the plurality of carriers and each of said plurality of sub-bands having a respective carrier of said plurality of carriers, a time multiplexer dividing each of said sub-bands by time-multiplexing the sub-bands into a plurality of frames, said time multiplexer also dividing each frame into N time-slots, and a switching device assigning a series of time-slots that occur periodically, every N time-slots, once per frame, to form channels for communication between said central station and said multiple stations wherein control is mapped to unidirectional channels and control channel messages are transmitted in one burst via said unidirectional channels in the downlink band to a first station, the control channel messages including assignment of uplink time slots to be used by the first station.