Trellis factor search PTS for PAPR reduction in OFDM

OFDM symbols exhibit a property of high peak-to-average power ratios (PAPR), which degrades system performance. Partial transmit sequence (PTS) is a kind of methods to depress the PAPR effectively. To obtain good trade-offs between complexity and performance on PAPR reduction using PTS schemes, a trellis structure based PTS factor search method is proposed and investigated in this paper. The trellis search is with a variant constraint length L_C, 1lesL_ClesV-1, where V is the number of PTS sub-blocks. The method is to decide a PTS factor by searching all possible paths obtained by varying L_C consecutive factors. Using different constraint length, trellis factor search PTS exhibits different PAPR reduction performance with different computation burden. The trellis search can be viewed as a general PTS factor search model including the full search and the iterative search appeared in previous papers