MISO CDMA transmission with simplified receiver for wireless communicationhandsets

The next-generation wireless personal and mobile communication systems are expected to accommodate not only high-quality voice services, but also a br oad range of other multirate services, Of the various multiaccess technique s, wide-band code-division multiple access (CDMA) has been regarded as an i mportant part of the third-generation wireless communication systems becaus e of its high frequency utilization efficiency and suitability for handling multimedia and multirate services, In this paper, we consider a system wit h a simplified receiver structure for direct-sequence CDMA (DS/CDMA) wirele ss communication handsets, in which improved performance is demonstrated wh en compared to a conventional DS/CDMA system with a RAKE receiver at the mo bile station, We arrive at this system by finding the optimal solution to a general multiple-input single-output (MISO) DS/CDMA smart antenna system. We find that this solution reduces to a pre-RAKE with space transmit divers ity system under the assumption that a simple one-finger matched filter is used at the receiver. This system combines the advantages of pre-RAKE diver sity and transmit antenna diversity. It is shown that significant system pe rformance and capacity improvements are possible. The numerical results als o reveal that this system is not too sensitive to channel estimation errors .