基于区域划分的双模式盲均衡算法研究

改进常模算法(MCMA)克服了常模算法(CMA)对相位不敏感的缺点,但收敛性能仍然较差。本文研究了依据区域划分将MCMA和判决引导(DD)算法有机结合的双模式盲均衡算法:通过综合考虑信噪比和剩余码间干扰,研究了区域划分边界的确定;讨论了不同模式中步长的选取;并应用滞后切换策略克服这种算法中的稳态误差波动问题。仿真表明:此算法收敛速度快、稳态误差小,并能在去除码间干扰的同时纠正信道固有的相位旋转和一定范围的载波频率偏移,具有很好的实用性。

Study on Dual-Mode Blind Equalization Algorithm Based on Decision Region

Modified constant modulus algorithm can overcome the constant modulus algorithm's shortcoming of insensitive to phase,but its convergence performance is still not good.A dual-mode blind equalization algorithm that unites the modified constant modulus algorithm and decision directed algorithm based on decision region is studied.The border of decision region is studied considering the Signal-to-Noise and residual intersymbol interference.The step-size choice in different modes is discussed,and a new delayed switching operation is used to avoid the fluctuation of the steady-state error.Simulations show that the new blind equalization algorithm has fast convergence rate and small steady-state error,at the same time it can correct the constant channel phase deflexion and a small carrier frequency offset simultaneously when removing the intersymbol interference,thus is of practical importance.