Patent ID: 7209455

Claim:
A physical layer interface system for a broadband wireless access communication network that establishes communication between a base station and a plurality of fixed subscriber stations over a radio link for multiplexing an upstream channel and a downstream channel, said downstream channel transporting downstream frames from the base station to the subscriber stations using a time division multiplexing (TDM) transmission protocol, and said upstream channel transporting upstream frames from the subscriber stations to the base station using a time division multiplexing access (TDMA) protocol, the physical layer interface system comprising: a first physical layer interface at said base station for broadcasting over said downstream channel a continuous string of downlink frames to all subscriber stations, and for receiving from each currently active subscriber station a burst of uplink frames over said upstream channel; and a second physical layer interface at said subscriber station for transmitting a respective burst in an assigned time-slot allocated in said upstream channel and for extracting the downstream frames addressed to the respective subscriber station; wherein the downstream frames have a fixed length, including a synchronization byte and a configurable-length payload field; and wherein the upstream frames have a frame size programmable in predetermined time increments and the virtual frame boundaries are determined from a downstream frame start indicator.