Increasing the speed of convergence of the constant modulus algorithm for blind channel equalization

The constant modulus algorithm (CMA) is an excellent technique for blind channel equalization. A signed error version of CMA (SE-CMA) and dithered signed error version (DSE-CMA) have been proposed which afford overall computational efficiency. We propose three different error functions for faster convergence. This would be essential for communication systems, which cannot afford a high startup delay or for systems, where the channel's impulse response is rapidly fluctuating. One of these algorithms relies on the idea of a variable step size, which increases the rate of convergence.