MAP Detection of Nonlinearly Distorted OFDM Signals

This paper presents the maximum a posteriori (MAP) detector for a multicarrier system with nonlinearity at the transmitter front-end. The analysis is based on block detection of multicarrier symbols. Since implementation of the MAP detector for a system with a large number of subcarriers is far too complex, a sub-optimum algorithm that can be implemented with acceptable complexity is also presented. It will be shown that when the nonlinearity distortion dominates the channel noise, without knowledge of the nonlinearity, the proposed detector outperforms the conventional ML detector