Abstract:
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 Amplifiers(PA). With 64-QAM OFDM signal, result shows that this method can improve Adjacent Channel Power Ratio(ACPR).
Key words:
Power Amplifier(PA),
predistortion,
Look Up Table(LUT),
hardware implementation,
loop delay,
phase coarse rotation
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。
关键词:
功率放大器,
预失真,
查找表,
硬件实现,
环路延迟,
相位粗旋转
CLC Number:
DONG Chuan-Cheng, CENG Zhen, TAN Xi, MIN Hao. Digital Predistortion Algorithm Suitable for Hardware Implementation[J]. Computer Engineering, 2012, 38(7): 230-232.
董传盛, 曾真, 谈熙, 闵昊. 一种适合于硬件实现的数字预失真算法[J]. 计算机工程, 2012, 38(7): 230-232.