legacy uplink subframe consists of three parts: HARQ Acknowledgement Channel (ACKCH); Ranging and Fast-Feedback; and the Channel Quality Indi- cation Channel (CQICH). The uplink control channels of the legacy system occupy the first three OFDM symbols of the uplink subframe immediately following the downlink-to-uplink switching gap in the TDD mode. The UL-PUSC subchannelization scheme is used in the uplink control region. 10.2 DOWNLINK CONTROL CHANNELS In order to minimize the control signaling overhead, and to improve the reliability and coverage of the control channels particularly at the cell edge, the control signaling schemes have been redesigned in DL Burst 1 DL Burst 1 UL Burst 1 UL Burst 1 DL Burst 4 DL HARQ DL Burst 4 DL MAP-IE MAP-IE UL HARQ UL MAP-IE UL Burst 2 UL Burst 2 MAP-IE DL Burst 2 DL Burst 2 DL HARQ DL MAP-IE MAP-IE UL HARQ UL MAP-IE MAP-IE UL Burst 3 UL Burst 3 DL Burst 5 DL Burst 5 Burst 3 DL Burst 3 DL-MAP UL-MAP DL-MAP UL-MAP MAP Region DL Subframe UL Subframe MAP Region DL Subframe UL Subframe (2-12 OFDM Symbols) (16-26 OFDM Symbols) (18 OFDM Symbols) (2-12 OFDM Symbols) (16-26 OFDM Symbols) (18 OFDM Symbols) Radio Frame = 5 ms Radio Frame = 5 ms (48 OFDM Symbols) (48 OFDM Symbols) Legacy Normal MAP Legacy HARQ MAP DL Burst 1 DL MAP-IE DL Burst 7 UL Burst 1 UL Burst 1 DL Burst 4 DL Burst 4 DL MÁP-IE DL MAP-IE UL MAP-IE UL Burst 2 HARQMAP UL Burst 2 Pointer DL Burst 2 DL Burst 2 UL MAP-IE DL MAP-1E UL MAP-IE UL Burst 3 UL MAP-IE UL Burst 3 DL Burst 5 DL Burst 5 Burst 3 DL Burst 3 Compressed Compressed Compressed DL/UL DL-MAP UL-MAP DL-MAP Sub-MAPs MAP Region DL Subframe UL Subframe MAP Region DL Subframe UL Subframe (2-12 OFDM Symbols) (16-26 OFDM Symbols) (18 OFDM Symbols) (2-12 OFDM Symbols) (16-26 OFDM Symbols) (18 OFDM Symbols) Radio Frame = 5 ms Radio Frame = 5 ms (48 OFDM Symbols) (48 OFDM Symbols) Legacy Compressed MAP Legacy Sub-MAPs FIGURE 10-1 Structure of various legacy MAPs (TDD mode) [1] CHAPTER 10 The IEEE 802. 16m Physical Layer (Part II) IEEE 802.1 16m. The jointly-coded MA