A frequency division duplex point-to-multipoint communications system comprising a central station adapted for communication with multiple mobile stations, wherein the system divides a frequency allocation into two bands, a downlink band that carries communications from a central station to multiple mobile stations, and an uplink band that carries communications from multiple mobile stations to the central station, the system comprising: a carrier generator adapted for 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 subdivided 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 adapted for dividing each of said sub-bands by time-multiplexing into a plurality of frames, said time multiplexer also adapted for dividing each frame into N time-slots, and a switching device adapted for 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 mobile stations, the central station adapted for assigning each mobile station a unique access request identifier during an initial request by the mobile station for an uplink traffic channel; the central station adapter for receiving an access control message from a requesting mobile station upon subsequent requests by the requesting mobile station for an uplink traffic channel, the access control message received the central station on a control channel where the access control message includes the ARI assigned to the requesting mobile station; the central station adapted to resolve access contention based on the ARI without requiring contention resolution via a traffic channel; the central station adapted to send an assignment control message by a single burst to the requesting mobile station, the assignment control message containing the ARI of the requesting mobile station and identity of the uplink traffic channel to be used. a carrier generator adapted for 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 subdivided 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 adapted for dividing each of said sub-bands by time-multiplexing into a plurality of frames, said time multiplexer also adapted for dividing each frame into N time-slots, and a switching device adapted for 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 mobile stations, the central station adapted for assigning each mobile station a unique access request identifier during an initial request by the mobile station for an uplink traffic channel; the central station adapter for receiving an access control message from a requesting mobile station upon subsequent requests by the requesting mobile station for an uplink traffic channel, the access control message received the central station on a control channel where the access control message includes the ARI assigned to the requesting mobile station; the central station adapted to resolve access contention based on the ARI without requiring contention resolution via a traffic channel; the central station adapted to send an assignment control message by a single burst to the requesting mobile station, the assignment control message containing the ARI of the requesting mobile station and identity of the uplink traffic channel to be used.