OFDM系统非线性自适应功率放大效能分析  

Effectiveness Analysis of Nonlinear Adaptive Power Amplifier for OFDM System

作　　者：杨剑[1] 

机构地区：[1]中国电子科技集团公司第十研究所,四川成都610036

出　　处：《通信技术》2016年第4期408-412,共5页Communications Technology

摘　　要：正交频分复用(OFDM)信号具有高的功率峰均比(PAPR),这就要求功率放大器必须具有大的功率回退以保证OFDM信号的线性度,其结果导致射频功率放大器的能量转换效率下降。讨论采用三种不同自适应偏置方案的非线性功率放大器对OFDM通讯系统性能的影响,并定义了一个反映系统无效功率的参数γ,通过计算机仿真获得了OFDM系统无效功率和相邻信道功率比(ACPR),从分析结果发现选择合适的功率回退量和自适应偏置方案可以大大降低OFDM系统的无效功耗。OFDM system signal is of fairly high PAPR （Peak-to-Mean-Envelope-Power Ratio）, and this would require large amplifier power back-off to ensure the linearity of OFDM system, thus leading to the decrease of power conversion efficiency of RF power-amplifier. The effects of three different adaptive bias schemes of nonlinear power amplifier on the performance of OFDM communication system are discussed, and a parameter γ that reflects the non-effective power of the system also defined. Computer simulation ac- quires the non-effective power and ACPR of OFDM system, and analysis indicates that the proper choice of amplifier power back-off and adaptive bias scheme could greatly reduce the non-effective power of OFDM system.

关 键 词：正交频分复用 无效功率 非线性功率放大器 相邻信道功率比 

分 类 号：TN911[电子电信—通信与信息系统]