A CMA adaptive array with digital phase shifters by a genetic algorithm and a steepest descent method

We consider CMA (constant modulus algorithm) adaptive arrays with digital phase shifters controlled by a genetic algorithm (GA) and a steepest descent method (SDM). As an example, 4- and 6- element circular arrays are considered. The element is a 50 ohm loaded dipole antenna. It is assumed that desired and undesired signals are /spl pi//4-shift-QPSK-modulated plane waves. The received signal at each receiving antenna element is calculated by the method of moments where mutual coupling effects are taken into account and is used as an input of the CMA adaptive processor. Then its convergence characteristics by the GA and the SDM are compared.