A Simple Method for the Evaluation of the BER Performance of Space-Time SMI-MVDR DS/CDMA Receivers

We propose a method to approximate the bit-error-rate (BER) performance of antenna-array-based CDMA systems employing sample-matrix-inversion (SMI) minimum-variance-distortionless-response (MVDR) space-time (ST) linear receivers. In the proposed method, a form of the Gaussian Q(ldr) function is approximated by a finite series of exponentially decaying cosines that are optimized using a recently proposed relative error measure. The proposed method provides accurate closed form approximations to the BER performance for a wide range of practical scenarios with very low complexity.