Receiver diversity scheme for OFDM systems

A simple receiver diversity scheme for orthogonal frequency division multiplexing (OFDM) systems is presented. Diversity combining is performed at the receiver before the discrete Fourier transformation (DFT) using a cyclic prefix. The scheme is shown to be equivalent to the conventional post-DFT maximal ratio diversity combiner. The computational complexity, or power consumption, can be reduced without any performance degradation when the number of antennas and the number of subcarriers are chosen properly.