Simulation of Blind Equalization of Constant Modulus Algorithm with Normalized Adaptive Conjugate Gradient Algorithm
Chun Li · Dalian Minzu Xueyuan xuebao · 2011
In order to improve the CMA blind equalization algorithm convergence rate,a kind of normalized conjugate gradient CMA blind equalization algorithm has been proposed and simulations have been performed.Used the cascade filtering,the input of blind equalizer has been redefined which can transfer the cost function of CMA to satisfy second normal form.And on this basis used adaptive conjugate gradient algorithm the equalizer weights have been updated.Meanwhile,the equalizer update input adopts power normalization process to ensure the stability of the algorithm.The computational complexity of conjugate gradient algorithm is lower than RLS and higher than LMS,and has faster convergence rate than LMS.The simulation results prove that normalization adaptive conjugate gradient algorithm has better performance than the traditional CMA blind equalization,and under complicated channel condition residue intersymbol interference can reduce 10dB,for the cascade filter adds to the equalization system can be taken as time-varying channel,which shows that the algorithm for time-varying channel is also effective.