最高功放效率PAPR抑制评估标准和迭代准则

高峰均功率比一直是掣肘OFDM系统性能的最大障碍。为了更精确地评估峰均比抑制对功放失真的影响,提出了最优CCDF(OCCDF)迭代收敛准则。新准则考虑放大器中每个子载波的失真,限定MER条件下得到尽可能低的放大器输入功率回退(IBO),获得最高功放效率所匹配的OFDM整体信号分布。基于此,在CMMB系统中给出了一种高效的时域削波结合星座图扩展(ACE)的峰均比抑制技术。采用OCCDF迭代峰均比抑制方案实验结果:MER=40 dB条件下,基于ACE峰均比抑制的OFDM系统相比抑制前获得了3.05 dB的功放IBO性能改善。对应到功率放大器的性能改善:功放效率提升了15.74%,总功耗和管耗分别降低了22.2%和40.19%。

PAPR Reduction Pedormance Evaluation Metric and Convergent Iterative Criterion with Maximizing HPA Efficiency

Orthogonal Frequency Division Multiplexing (OFDM) is limited mainly by its high Peak-to-Average Power Ratio (PAPR). In this work, we proposed an optimal CCDF (OCCDF) convergence criterion since it can predict high-power amplifier (HPA) power distortion more accurately. In this evaluation criterion, an analytical approach to calculate the non-linear distortions of each sub-carrier is proposed, to achieve a minimized input power back off (IBO) of HPA with more suited OFDM signals for a MER limited. Based on this evaluation platform, a clipping with active constellation extension (ACE) in CMMB system is simulated. It finally gives the performance results obtained with the proposed evaluation platform: The implementation of OCCDF method is shown to offer a 3.05 dB IBO performance gain (at a MER of 40 dB), an improvement of 15.74% in HPA efficiency, a reduction of 22.2% and 40.19% in the total power and power dissipation, respectively when compared to the traditional OFDM transmission without reducing PAPR.