Patent ID: 8774297

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: transmitting a first signal including first spread ACK/NACK information in an orthogonal frequency division multiplexing (OFDM) symbol, the first spread ACK/NACK information existing only in a first antenna set in a form as shown in an upper half of Table 1; and transmitting a second signal including second spread ACK/NACK information in an OFDM symbol, the second spread ACK/NACK information existing only in a second antenna set in a form as shown in a lower half of Table 1: TABLE 1 four available neighboring subcarriers the first antenna A a 1 a 2 a 3 a 4 antenna set antenna B −a 2 * a 1 * −a 4 * a 3 * the second antenna C b 1 b 2 b 3 b 4 antenna set antenna D −b 2 * b 1 * −b 4 * b 3 * wherein a 1 to a 4 are first to fourth elements, respectively, of the first spread ACK/NACK information, b 1 to b 4 are first to fourth elements, respectively, of the second spread ACK/NACK information, and the symbol “*” denotes 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 four available neighboring subcarriers for the first spread ACK/NACK information are separated from the four available neighboring subcarriers for the second spread ACK/NACK information by a plurality of subcarriers in a frequency domain.