基于PTS级联抵消的峰均比抑制性能仿真

Simulation on PAPR Improvement Based on Joint Scheme of PTS and Peak-cancellation

提出了PTS级联抵消算法,实现对地面数字多媒体广播系统中时域同步正交频分复用信号的峰均功率比的抑制。通过研究地面数字多媒体广播系统传输协议,分析了采用时域同步正交频分复用多载波调制方式对系统射频前端信号时域性能的影响。针对信号峰均功率比高的缺陷,提出一种新颖的峰值功率比抑制算法。该算法对峰均功率比的抑制能力强于传统PTS算法,引起的带外辐射和互调失真小于传统限幅技术。当子载波数较大时,仍可实现对系统峰均功率比的有效控制。通过仿真,与传统限幅技术相比,算法可以使地面数字多媒体广播系统的峰均功率比控制在4-5dB,比传统PTS算法峰均功率比减小约3-4dB,且仅有少量的误码率性能损失。

New joint scheme of partial transmit sequence （PTS） and peak-cancellation technique was proposed to reduce the peak-to-average power ratio of time-domain synchronous OFDM signals in terrestrial digital multimedia/TV broadcasting system. The terrestrial digital multimedia/TV broadcasting protocol and the effects of its time-domain synchronous OFDM modulation method at RF front-end were analyzed. For the induced high crest factors of time-domain synchronous OFDM modulation, a novel peak-to-average power ratio reduction method was proposed. The method can obtain a better peak-to-average power ratio performance for terrestrial digital multimedia/TV broadcasting system then ordinary PTS method. Its influence on the undesirable out-of band radiation and inter-modulation distortion is small. By simulation, it is shown that the new algorithm can achieve the PAPR value about 4-5dB which is about 3-4dB lower than that of the traditional peak-to-average power ratio reduction methods. It also has good bit error ratio performance.