Patent ID: 8379878
Filing Date: 2013-02-19
Classification: H04B,H04L

Abstract:
1. A transmission apparatus which provides diversity gain in an Orthogonal Frequency Division Multiplexing (OFDM) system, the transmission apparatus comprising: a Serial-to-Parallel (S/P) converter for converting an input transmission signal into parallel signals; a pre-coder for pre-coding the parallel signals with a predetermined frequency offset; an Inverse Discrete Fourier Transform (IDFT) unit for performing IDFT on the pre-coded signals; and a Radio Frequency (RF) unit for up-converting the IDFT signals and outputting the up-convertedsignals to a wireless network, wherein a signal point on a constellation of basis vectors is expressed according to the frequency offset as: where n=0, 1, . . . , (M−1), k=1, 2, . . . , M, and M indicates a size of the pre-coder, the frequency offset is set in order not to span basis vectors of a Discrete Fourier Transform (DFT) kernel, and the span of the basis vectors of the DFT kernel is caused by an error signal constellation between digital audio signal modulations.