Patent ID: 8792570

Claim:
A method for transmitting Acknowledgement/Negative Acknowledgement (ACK/NACK) information in a mobile communication system, the method performed by a base station and comprising: generating first spread ACK/NACK information using an orthogonal sequence with a spreading factor of 4; generating second spread ACK/NACK information using the orthogonal sequence; coding the first spread ACK/NACK information as shown in Table 1; and coding the second spread ACK/NACK information as shown in Table 2: TABLE 1 First set of four available neighboring subcarriers in an OFDM symbol antenna A a 1 a 2 a 3 a 4 antenna B −a 2 * a 1 * −a 4 * a 3 * antenna C 0 0 0 0 antenna D 0 0 0 0 TABLE 2 Second set of four available neighboring subcarriers in an OFDM symbol antenna A 0 0 0 0 antenna B 0 0 0 0 antenna C a 1 a 2 a 3 a 4 antenna D −a 2 * a 1 * −a 4 * a 3 * wherein a 1 to a 4 are respectively associated with first to fourth elements of the first spread ACK/NACK information, and b 1 to b 4 are respectively associated with first to fourth elements of the second spread ACK/NACK information, wherein the “*” symbol represents a conjugate operation, wherein the first spread ACK/NACK information and the second spread ACK/NACK information carry identical ACK/NACK information, and wherein the first set of four available neighboring subcarriers are separated from the second set of four available neighboring subcarriers by a plurality of subcarriers in a frequency domain.