Side information in PAR reduced PTS-OFDM signals

Orthogonal frequency division multiplexing suffers from large peak-to-average power ratios (PAR). Large PAR causes undesirable effects such as signal distortion and unwanted out of band radiation. Use of partial transmit sequences (PTS) is proposed to improve the PAR statistics of OFDM signals. Phase angles of the modulated symbols are changed in PTS to reduce the PAR. The information about these changes (side information) is critical for the successful operation of PTS. However, a proper way to send side information to the receiver without affecting the optimized PAR statistics has not been reported in the open literature so far. In this paper, we present a novel scheme to insert the side information into PTS-OFDM signals without affecting the improved PAR statistics. Simulation results show that the proposed scheme does not contribute to any peak-regrowth and the hit error rate performance of the system is improved.