Power and Bandwidth-Efficient Circular M-Ary APSK Schemes with Low PAPR

Abstract

This paper presents a class of circular M-ary Amplitude-Phase Shift Keying (APSK) signaling techniques with high bandwidth efficiency and low peak-to-average power ratio (PAPR) suitable for systems using nonlinear power amplifiers to achieve high power efficiency. For nonlinear amplification, good performance requires not only high squared minimum distance to average power ratio (DPR) but also low PAPR. A search algorithm for M-ary APSK schemes using circular constellations suitable for nonlinear amplification with minimum PAPR and maximum DPR is developed. Results for 8-, 16-, 32-, 64- and 128-APSK signalling schemes are presented. The effects of bandlimiting filter sharpness on the PAPR are examined and considered in the development. The analytical and simulation results show that this class of circular M-ary APSK signals outperforms the square and cross M-ary QAM schemes.