On the accuracy of phase noise bandwidth estimation in OFDM systems

Phase noise is of importance in OFDM systems, since it generates intercarrier interference and general system performance degradation. In this paper we analyse the accuracy of maximum likelihood estimation of the phase noise bandwidth for OFDM systems. We utilize the auxiliary functions used in the EM algorithm to obtain an expression for the Fisher information matrix. Our key conclusion is that it is difficult to obtain accurate estimates of the phase noise bandwidth for practical cases when the number of subcarriers is limited.