The remaining distributed LRUs in that subframe are used for control and data transmission. The first NP-SFH distributed LRUs of the first subframe are allocated for P-SFH transmission, where NP-SFH has a fixed value. The S-SFH is mapped to the NS-SFH distributed LRUs following the NP-SFH distributed LRUs. The value of parameter NS-SFH is determined by the S-SFH repetition factor and the total number of information bits in S-SFH IE (variable depending on the type of S-SFH subpacket being transmitted) plus the 16-bit S-SFH CRC. The S-SFH can be repeated over two consecutive superframes to achieve time diversity. The information transmitted in S-SFH is divided into three sub-packets. The sub-packets of S-SFH are transmitted periodically where each sub-packet has a different transmission periodicity, as illustrated in Figure 9-63. The SP Scheduling Periodicity Information field of S-SFH SP3 is used to indicate the transmission peri- odicity of the S-SFH SP1, SP2, and SP3. When no S-SFH sub-packet is contained in the SFH, the S-SFH resources may be used for transmitting other control information or the A-MAPs. The P-SFH and S-SFH are transmitted using predetermined modulation and coding schemes. The modulation for the P-SFH and the S-SFH is QPSK. The effective coding rate for the P-SFH is 1/24 and the effective coding rate for the S-SFH is configurable and signaled by the P-SFH. The physical processing of the P-SFH IE is shown in Figure 9-64. A 5-bit CRC is appended to P-SFH IE whose generating polynomial is described as G(x) x2 + 1. The CRC length for the S-SFH is 16 bits. A Tail-Biting Convolutional Coder with a rate of 1/4 is used as the minimum code rate for the P- SFH and S-SFH. The modulated symbols are mapped to two transmission streams using an SFBC transmit diversity scheme. The two streams using SFBC are precoded and mapped to the transmit antennas. The MS is not required to know the antenna configuration prior to decoding the P-SFH. When using more than two transmit-antennas, the P-SFH and S-SFH are transm