Patent ID: 7483364

Claim:
A method of detecting transmit data symbols X 0;m , . . . , X A−1;m in an STBC-OFDM communication system in which A transmit data symbols X 0;m , . . . , X A−1;m are STBC encoded and OFDM modulated during B OFDM symbol periods for each sub-channel m (m=0, 1, . . . , N−1) and are then transmitted through P (P>1) transmit antennas, comprising: a step of demodulating STBC-OFDM modulation signals into Y 0;m , . . . , Y B−1;m using FFT; a step of estimating frequency responses H 0;m i , . . . , H B−1;m i (i=1, 2, . . . , P) for each sub-channel; an STBC decoding step of calculating decision variables R 0;m , . . . , R A−1;m for determining the transmit data symbols X 0;m , . . . , X A−1;m that are transmitted for each sub-channel; and a step of determining the transmit data symbols X 0;m , . . . , X A−1;m based on the decision variables R 0;m , . . . , R A−1;m calculated at the STBC decoding step; wherein the STBC decoding step calculating the decision variables R 0;m , . . . , R A−1;m by a linear equation that allows a squared Euclidean distance D m from OFDM reception symbols Y 0;m , . . . , Y B−1;m to have a local minimum for each decision variable when the STBC encoding and the frequency responses H 0;m i , . . . , H B−1;m i are applied to the decision variables R 0;m , . . . , R A−1;m .