Patent ID: 7606320
Filing Date: 2009-10-20
Classification: H04B

Abstract:
1. A transmitter using a plurality of (Nt) transmit antennas in a communication system, comprising: a pre-coder for pre-coding an input symbol sequence using a pre-coding matrix, the pre-coding matrix being produced by puncturing a unitary matrix in a predetermined method; and a space-frequency coder for generating a plurality of vectors by grouping the symbols of the pre-coded symbol sequence by twos, space-frequency mapping each of the vectors by encoding each of the vectors in an Alamouti coding scheme, and providing each of the space-frequency mapped symbols to a predetermined Orthogonal Frequency Division Multiplexing (OFDM) modulator; wherein if a number of the transmit antennas is an even number (Nt=even number), the pre-coding matrix is where a i =exp(2π(i1/4)/N t ), i=,0, 1,2, . . . ,N t/ 2−1, and wherein the pre-coding matrix is produced by puncturing predetermined columns in an N t ×N t Vandermonde matrix, sequentially grouping the rows of the punctured matrix by twos, and shifting one row of each group.