Non-uniform sampling point selection in OFDM receiver with fractional sampling

To achieve diversity with a single antenna, a fractional sampling (FS) scheme in OFDM has been proposed. In the previous literatures for FS, the sampling interval is fixed. An oversampling rate needs to be large to obtain more path diversity gain through FS. This leads to the increase of a circuit size for demodulation in a mobile terminal. In this paper, sampling point selection according to the frequency response of a channel has been proposed. The proposed scheme reduces the number of demodulation branches to a half as compared to the conventional FS scheme to achieve the same bit error rate. Moreover, by eliminating the specific sets of the sampling points, the computational complexity for sampling point selection is also reduced by a factor of 2.