Suppression algorithm of phase noises in OFDM system based on interpolation combined with MMSE equalization

Aiming at the orthogonal frequency division multiplexing (OFDM) system is sensitive to the phase noise, a suppression algorithm of phase noises in OFDM system based on interpolation combined with MMSE equalization is introduced. Before IFFT in the transmitter, interpolating the zero subcarriers into the symbol may reduce the inter carrier interference (ICI) effectively and improve the signal-to-interference (SIR) ratio. By using the MMSE equalization method, the common phase error (CPE) of the OFDM system caused by the phase noise can be eliminated. The simulation results show that the algorithm can eliminate the rotation of the constellation caused by CPE and suppress the cloud of divergence of the constellation caused by ICI. The phase noise of the OFDM system can be suppressed effectively over Gauss channel and multipath channel, so the proposed algorithm has low complexity and is good in practice.