Co-channel interference cancellation for DS-SS CDMA mobile communication system

In this paper, an elaborate co-channel interference (CCI) cancellation technique is introduced for the DS-SS CDMA mobile communication system. The performance of the CCI canceller (Yoon, et al., 1993) is extended and evaluated at the mobile station (MS) receiver operating in an extreme (worst) interference condition. The interference is a result of intersymbol interference (ISI) and multi-access interference (MAI) generated within the mother cell and from the neighboring cells. The MS, operating in a mobile communication system with a reuse factor of one, is assumed to be at the center of a triangle formed by three heavily loaded base stations (BS). The theoretical analysis of the system indicates that the co-code CCI (CCCCI), which is a CCI from users operating with the same spreading sequences in the neighboring cells, is a major degradation factor for the proposed systems´ performance. Simulation results are also used to evaluate the system performance using the signal to noise ratio (SNR) and bit error rate (BER) versus the number of interfering users from within the cell and from the surrounding cells, and the normalized mean square error in parameters estimation (MSE)