Improved pilot-symbol assisted estimation of integer frequency offset for OFDM system with cyclic delay diversity

Cyclic delay diversity (CDD) is a simple transmit diversity technique for coded OFDM systems with multiple transmit antennas. It is applicable to existed wireless communication systems since it does not need modifications of the standard OFDM receiver. However, CDD causes serious degradation in the performance of post-FFT estimation, i.e., integer frequency offset (IFO). This paper suggests pilot allocation method and IFO estimator which is designed for the purposed of weakening the effect of frequency-selective fading caused by CDD. The simulation result shows that the proposed method can provide benefit to the overall system performance.