dulation and I/Q multiplexing, each PHICH channel can carry up to eight acknowledgments for a normal cyclic prefix [107]. The Physical Control Format Indicator Channel (PCFICH) is used to dynamically indicate the number of OFDM symbols used for the control region in a subframe. The PCFICH is transmitted in the first OFDM symbol of the subframe and the three values are indicated by three sequences 16 QPSK symbols in length. Predefined codewords based on (3, simplex coding with repetition and systematic bits with dmin = 21 is used. To provide maximum frequency diversity, the PCFICH is transmitted over the entire system bandwidth. Transmit diversity is also supported using the same diversity scheme as the PDCCH. In addition, cell specific scrambling, tied to the cell ID, is utilized. The PBCH has a fixed and predefined transmission format and is broadcast over the entire coverage area of the cell. In 3GPP LTE, the broadcast channel is used to transmit the System Information which is essential for network access. Due to the large size of the System Information field, it is divided into two segments: Master Information Block (MIB) which is transmitted in PBCH; and System Infor- mation Blocks (SIB) that are transmitted in PDSCH. The PBCH contains the basic system configu- ration parameters necessary to demodulate the PDSCH which contains the remaining System Information Blocks. The PBCH is characterized by a single fixed-size transport block per TTI, QPSK modulation scheme, it is transmitted on 72 active sub-carriers that are centered around the DC sub- carrier, and no HARQ is used for PBCH (see Figure 9-76). The Master Information Block is trans- mitted on the PBCH over 40 ms as shown in Figure 9-77. The CRC masking is used to implicitly provide the UE the number of transmit antennas at the eNB (1, 2 or 4). Tail-biting convolutional coding with minimum rate of R = 1/3 and repetition is used, and the coded bits are rate-matched to 1920 bits for normal CP and 1728 bits for extended cyclic prefix. The coded BCH transport