A Factor Graph Approach to the Iterative Detection of OFDM Signals in the Presence of Carrier Frequency Offset and Phase Noise

This paper provides a new iterative solution to the problem of the joint estimation of phase noise and residual carrier frequency offset in an orthogonal frequency division multiplexing transmission over a multipath fading channel, in the presence of known data and channel impulse response. The proposed technique results from the application of the sum-product algorithm to a factor graph representing the joint a posteriori probability density function of the carrier frequency offset and the phase noise vector affecting a given symbol. The resulting algorithm is shown to be exploited in a coherent receiver for both data-aided training and decision-directed tracking. Its performance is assessed by computer simulations and is compared with that provided by other strategies.