ABSTRACT
Beamforming is a versatile approach to signal spatial ltering that has found numerous applications in diverse areas, including radar, sonar, wireless communications, geophysics, speech and audio processing, ultrasonic imaging, biomedicine, radio astronomy, and other elds [1]. Early attempts of applying beamforming to wireless communications go back to the late 1970s and early 1980s [2-4]. During the last two decades, there has been a major trend to use multiantenna transceivers in wireless communication systems to facilitate the explosive growth of the number of users and meet their rapidly increasing demands for new high-data-rate services [5-20]. As a result, spatial division multiple access (SDMA) technology recently became one of the key concepts in third and higher generations of mobile communication systems. In particular, the receive (uplink) and
8.1 Introduction .......................................................... 201 8.2 Basic Signal Models ..............................................202
