Wireless communications for mobile telephone and data transmission is currently undergoing very rapid development. The emerging wireless systems will incorporate considerable signal processing intelligence in order to provide advanced services such as multimedia transmission. In order to make optimum use of available bandwidth, many wireless systems operate as multiple access systems, e.g. Direct Sequence Code Division Multiple Access (DS-CDMA), in which the users are multiplexed by distinct code waveforms. Two major factors that limit the performance of DS-CDMA systems are multiple access interference and multipath channel distortion. Many advanced signal processing techniques have been proposed to combat these factors. Among these techniques, one of the more promising is the use of Smart or Adaptive antennas.