Path diversity with fractional delay transmission for fractional sampling-MIMO-OFDM system

Through fractional sampling (FS) it is possible to separate multipath components and achieve path diversity. However, if no path component whose delay corresponds to the sampling point, FS cannot obtain diversity gain. In this paper, a novel scheme to improve the performance with FS over a sparse multipath channel is proposed. The proposed scheme uses multiple transmit antennas and sends multiple signals with fractional delays. The performance improvement with the proposed scheme is confirmed through computer simulation. It is shown that the proposed scheme increases the capacity of a MIMO-OFDM system by a factor of 1.5 to 2 and improves the BER performance on the sparse multipath channels.