Use of Preset Reserved Tones in Reduction of PAPR in OFDM Systems

In this paper, a proposed sub-optimal iterative re-weighted least-squares tone reservation method is applied to reduce PAPR in OFDM systems with fixed locations of reserved tones. Three ways of placing the reserved tones are investigated and compared: random, contiguous, and equal-spaced placements in OFDM symbols. The proposed method has a fast quadratic convergence and low per iteration complexity of O(NL) where N is the number of reserved sub3carriers, and L is the number of the reserved tones. The method was found to achieve, respectively, high PAPR reductions of 5.3 dB for the random and 4.5 dB for both the contiguous and equal-spaced placements when only 5% of the total number of subcarriers is reserved for PAPR reduction. These PAPR reductions are higher than from other related optimal and sub-optimal methods reported in literature.