Analysis on the Performance of Doppler Diversity Receiver with Different Combining Methods

Abstract

The Doppler frequency shift can do great harm to the performance of OFDM systems, so how to design the OFDM receiver under mobile environment is an important topic. An efiective Doppler diversity receiving technology for OFDM was proposed by Kim B C, which can achieve much better Bit Error Rate (BER) performance than the conventional OFDM receiver. In this article, we make research on the performance of the Doppler diversity receiving technology when using difierent combining methods, including the Orthogonality Restoring Combining (ORC) method, the Equal Gain Combining (EGC) method, the Maximal Ratio Combining (MRC) method and the Minimum Mean Square Error Combining (MMSEC) method. The research and simulation results show that in the Doppler diversity receiver, the BER performance of the ORC method is worse than that of the method without diversity, while the BER performance of the EGC method, the MMSEC method and the MRC method are better than that of the method without diversity. Moreover, the MRC method can achieve the best BER performance among the four combining methods mentioned above.