【摘要】 为了增加FIR-ALE(Finite Impulse Response-Adaptive Linear Enhancer)相位噪声补偿系统的补偿能力,本文基于LMS算法对Cupo的FIR-ALE系统进行改进,并对8PSK调制方式下的信号进行了Matlab仿真,通过对信号功率谱、误比特率以及星座图的分析,对比了两种方法.仿真结果表明,改进后的系统对于幅度为5°、频率为120 Hz的相位抖动,能够将抖动衰减25 dB左右;对于幅度为15°、频率为25 Hz的相位抖动,改进后的LMS系统能将抖动衰减35 dB左右.而且,随着相位抖动幅度的增大,改进的LMS方法的补偿能力同Cupo的FIR-ALE方法比较,性能逐渐提高.更多还原

【Abstract】 In order to improve the compensation ability of FIR-ALE(Finite Impulse Response-Adaptive Linear Enhancer) system for phase noises,an improved method based on LMS algorithm is discussed in this article.The simulation of 8PSK modulation signals with Matlab is also illustrated.These two kinds of methods are compared through analyses of power spectrums,BER and constellation.Simulation results prove that the improved LMS system can reduce the phase jitter by almost 25 dB when the jitter amplitude is 5° and the frequency is 120 Hz,and the system can reduce the phase jitter by 35 dB when the jitter amplitude is 15° and the frequency is 25 Hz.Moreover,the compensation ability of the improved LMS method is enhanced with the increasing jitter amplitude compared with that of the FIR-ALE method.更多还原