A frame format used in a wireless communication system, more particularly an OFDMA TDD wireless communication system, of the kind that includes 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 the 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.