Abstract: A method and apparatus for requesting and allocating bandwidth in a broadband wireless communication system. The inventive method and apparatus includes a combination of techniques that allow a plurality of CPEs to communicate their bandwidth request messages to respective base stations. One technique includes a “polling” method whereby a base station polls CPEs individually or in groups and allocates bandwidth specifically for the purpose of allowing the CPEs to respond with bandwidth requests. The polling of the CPEs by the base station may be in response to a CPE setting a “poll-me bit” or, alternatively, it may be periodic. Another technique comprises “piggybacking” bandwidth requests on bandwidth already allocated to a CPE. In accordance with this technique, currently active CPEs request bandwidth using previously unused portions of uplink bandwidth that is already allocated to the CPE.

Abstract: An adaptive time division duplexing (ATDD) method and apparatus for duplexing transmissions on a communication link in wireless communication systems. Communication link efficient is enhanced by dynamically adapting to the uplink and downlink bandwidth requirements of the communication channels. Time slots are flexibly and dynamically allocated for uplink or downlink transmissions depending upon the bandwidth needs of a channel. Communication link bandwidth requirements are continuously monitored using sets of predetermined bandwidth requirement parameters. Communication channels are configured to have either symmetric or asymmetric uplink/downlink bandwidths depending upon the needs of the channel. Channel bandwidth asymmetry can be configured alternatively in favor of the uplink transmissions (i.e., more time slots are allocated for uplink transmissions than for downlink transmissions) or in favor of the downlink transmissions (i.e.