A lower-complexity iterative trellis-based factor search algorithm and blind detector for PTS-based OFDM systems

It is known that partial transmit sequence (PTS) is an effective technique to mitigate the problem of high peak-to-average power ratio (PAPR) in an orthogonal frequency-division multiplexing (OFDM) system. One of the major drawbacks of PTS lies in the high complexity for searching the optimal weighting-factor (phase-rotation) vector. In this paper, a trellis-based iterative algorithm is proposed to choose an appropriate weighting-factor vector. Compared to a previously-proposed non-iterative trellis-based algorithm, the proposed iterative algorithm can achieve a comparable PAPR performance with a lower search complexity. Since explicit side information is not transmitted to the receiver of the OFDM system under investigation, we use a phase-quantization-based receiver, which was originally used in noncoherent receivers, to recover the transmit data. Using such a blind receiver, we can achieve a comparable error performance with a lower complexity compared to previously-proposed blind and semi-blind receivers.