A method of transmitting acknowledgment/ nonacknowledgement (ACK/NACK) signals including multiplexing ACK/NACK signals; and repeatedly transmitting for predetermined times the multiplexed signal with each of repetitions of transmitting the multiplexed signal being spread in a frequency domain and being mapped to a plurality of discrete resource units each having a pair of neighboring subcarriers and a predetermined number of Orthogonal Frequency Division Multiplexing (OFDM) control symbols. A method for transmitting Category 0 bits, including modulating the Category 0 bits; repeatedly transmitting the modulated Category 0 bits with each of repetitions of transmitting the modulated Category 0 bits being spread in a frequency domain and being mapped to a plurality of discrete resource units each having a pair of subcarriers and a predetermined number of OFDM control symbols; and mapping the modulated Category 0 bits by a frequency selective transmit diversity (FSTD).
TRANSMIT DIVERSITY FOR ACKNOWLEDGEMENT AND CATEGORY 0 BITS IN A WIRELESS COMMUNICATION SYSTEM