DS/CDMA code-diversity communication system using adaptive weight control

In this paper, we propose a code-diversity system using adaptive weight control (AWC) to suppress multiple access interference in DS/CDMA system. This proposed system is modified from a conventional code-diversity system using a constant amplitude composite sequence. In a conventional system, interference suppression performance is much degraded against the increment of multiple access users. The reason is the difference of diversity weights become a little when the variance of multiple access interference increases. In the proposed system, the diversity weight is calculated adaptively by the LMS algorithm to improve suppression performance over the above environment. The interference suppression performance of the proposed system is evaluated by computer simulations.