Hybrid-Domain Evaluation PTS with Adaptive Selection Methods for PAPR Reduction

Abstract

The partial transmit sequence (PTS) technique is a fairly suitable scheme to mitigate the high peak-to-average power ratio (PAPR) problem inherent in 5G multicarrier systems, especially considering a high-order QAM modulation design. However, the high computational complexity level and the speed of the convergence for optimizing the phases of the transmitting signal restrict this technique in practical applications. In this paper, a low-complexity frequency-domain-evaluated PTS (F-PTS) based on a spacing multiobjective (SMO) processing algorithm is proposed to reduce the PAPR values. The PAPR performance are accurately predicted in terms of modifying relative dispersion in the frequency domain. As a result, the complexity of searching the optimal phase factors and IFFT computing is simplified. Moreover, a frequency-domain- and time-domain-evaluating PTS (FTD-PTS) is employed to search the optimal solution with a reasonable complexity. Simulation results verify that the operation rate of F-PTS is significantly improved after transferring the exhaustive search strategy of PTS into the SMO algorithm, and the F-PTS PAPR reduction performance is just 0.3 dB away from theoretical optimal performance. The FTD-PTS spends an acceptable operation rate to obtain optimal PAPR reduction performance, which subtracts 0.5 and 0.6 dB more than PSO-PTS and conventional PTS at CCDF=10−3, respectively.

A Novel Low Complexity Two-Stage Tone Reservation Scheme for PAPR Reduction in OFDM Systems

“…Nowadays, many researchers have proposed various well-known technologies to reduce PAPR in OFDM systems [ 11 , 12 , 13 ], such as clipping, SLM, PTS, TI, TR, etc. Among them, the clipping technique [ 14 , 15 ] is the easiest to implement, because only the input signal needs to be limited, but the clipped signal is prone to nonlinear distortion, and the location and size of the clipping are difficult to decide and store, which results in BER performance degradation [ 16 ] and spectral efficiency decline.…”