Novel mixed constant modulus blind equalizer for underwater acoustic channel
Yecai Guo, Zhao Jun-wei · Systems engineering and electronics · 2005
For greatly improving the convergence rate of constant modulus algorithm(CMA) and reducing the mean square error of sign error constant modulus algorithm(SECMA), a novel mixed constant modulus cost function is defined using constant modulus cost function and sign error constant modulus cost function, and its feature is analyzed in theory. Mixed constant modulus algorithm(MCMA), which can be updated by gradient vector of constant modulus cost function and that of sign error constant modulus cost function, is developed. In the MCMA, adjusting the scale coefficients of two gradient vectors can improve the convergence rate and reduce residual mean square error. The efficiency of the MCMA is proved via computer simulation of underwater acoustic channel equalization.