一种适合于硬件实现的数字预失真算法

摘要

传统的数字基带预失真算法较复杂不易实现.为此,设计一种适合于硬件实现的数字预失真算法.考虑对模拟射频部分引入的环路延迟和相位偏转的补偿,采用2块大小为32×16的查找表作为预失真模块,存储针对不同输入幅度信号的调整系数,以预先抵消功率放大器的失真.用调制方式为64QAM OFDM信号进行测试,结果表明,该算法的预失真性能较好.%Since most algorithms for predistortion are too complex to implement, this paper designs an efficient algorithm of digital predistortion suitable for implementation with two 32×16 Look Up Table(LUT) as the predistortion block, considering the loop delay of the analog/RF circuits and the phase rotation. Coefficients used to predistort input signal are stored in LUT in order to compensate for distortion of Power Amptifiers(PA). With 64-QAM OFDM signal, result shows that this method can improve Adjacent Channel Power Ratio(ACPR).