Receiver algorithms for OFDM systems in phase noise and AWGN

In this paper we address the subject of reducing the impact of phase noise on a QAM-OFDM system transmitting over an AWGN channel. Phase noise is known to have two effects on OFDM systems, rotating each symbol by a different common phase rotation (CPR) and producing an intercarrier interference term (ICI) that adds to the channel noise. We present two novel algorithms that remove CPR and reduce the amount of ICI using different approaches to the ICI problem. Their performance in terms of bit error rate (BER) are evaluated by simulation using symbol by symbol or maximum likelihood sequence detection (MLSD). The results show that these algorithms can significantly reduce the BER floor of the system while still maintaining an acceptable throughput.