Despread-Respread Multi-Target Constant Modulus Array for CDMA Systems

In this letter, we apply the concept of the despread-respread (DR) algorithm to multi-target arrays for code-division multiple-access (CDMA) signals. The despread-respread algorithm exploits the knowledge of the pseudo-noise (PN) code used to generate the transmitted CDMA signal. We extend the DR algorithm to not only exploit the knowledge of the PN code but also to preserve the constant modulus property of the signal. This new algorithm is called the Least Squares Despread Respread Multi-target Constant Modulus Array (LS-DRMTCMA). LS-DRMTCMA performs better than the Least Squares Despread Respread Multi-Target Array (LS-DRMTA), Least Squares Multi-Target Constant Modulus Array (LS-MTCMA) [1], and Steepest Descent Multi-Target Decision Directed Array (SD-MTDDA).