Joint channel estimation and peak-to-average power reduction in coherent OFDM: a novel approach

A new peak-to-average power reduction approach for OFDM has been addressed. Two-dimensional pilot-symbol assisted modulation (2D-PSAM) is employed in coherent OFDM for channel estimation and it is based on inserting known symbols spreaded out throughout the 2D time-frequency grid. We show that these scattered symbols can also be employed to perform distortionless peak power reduction, with a negligible loss in data-rate. To reduce additional system complexity and side information, several suboptimal strategies are proposed. A comparison between the two schemes with different approaches to the joint design of pilot symbols for both channel estimation and peak power reduction, has also been carried out.