Frame structure for a wireless communication system

Abstract

A frame format used in a wireless communication system, more particularly an OFDMA TDD wireless communication system, of the kind comprising a base station and a plurality of fixed or mobile subscriber stations, the base station maintaining connections with each of the subscriber stations by performing wireless communication in units of frames having said frame format, and within each frame, allocating resources for data transmission and signalling. Each frame has a plurality of downlink subframes and a plurality of uplink subframes including, in time order, a first downlink subframe, a first uplink subframe, a final downlink subframe and a final uplink subframe. One or more further downlink subframe/uplink subframe pairs may be interposed between the first and final subframes as desired, and the configuration can be changed dynamically. The frame structure is capable of adapting to a system that is evolving from supporting predominantly legacy terminals to one which will be supporting an increasing number of enhanced terminals. The coexistence of both legacy and enhanced terminals within the proposed frame structure will have minimal impact of the performance of legacy subscriber stations. Depending on the required number of either legacy or enhanced terminals that need to be supported, the base station has the ability to define a frame configuration where the number of subframes per frame is configured based on the feature set of the operational subscriber stations and the mobility requirements of enhanced subscriber stations such that the frame structure at all times retains sufficient features to support the attachment of legacy stations that do not support the enhanced features.

Dependencies are inferred from the claim text.