Stationary points of the constant modulus algorithm for real Gaussian signals
C.K. Chan, John J. Shynk · IEEE Transactions on Acoustics Speech and Signal Processing · 1990
An analysis of the stationary points for four versions of the constant modulus algorithm (CMA) when the received signal is a zero-mean, real Gaussian process is presented. With this type of signal, it is well known that CMA generally cannot equalize a communication channel; the analysis of the CMA performance function demonstrates how this occurs. It is shown that in each case the stationary points are determined by a condition on the variance of the equalizer output, and they depend only on the modulus factor r and the received signal correlation matrix R. As a result, there can be an infinity of weight vector solutions, each corresponding to a stationary point of the CMA performance function.>