Abstract:

Multiple input multiple output and smart antenna (MIMO/SA) system is one of the key technologies for the fourth generation mobile communications system, mutual coupling is the main factor which affects the performence of MIMO/SA multiantenna systems. A combination model of MIMO and SA is presented. With the existing of mutual coupling effects the expressions of spatial correlation and channel capacity are derived. The ergodic capacity of MIMO/SA multiantenna systems is simulated using electromagnetic numeric method and Monte-Carlo method. The results show that in the typical power azimuth spectrum distribution, the channel capacity which takes mutual coupling into account oscillates up and down around the  channel capacity without mutual coupling while changing the distance of the antennas|the channel capacity increases continually while increasing the distance of base station antenna array|when antennas distance of the mobile station is farther than 0.5 wavelength the channel capacity remains almost the same even though the antenna array distance increases |and mutual coupling increases the channel spatial correlation of MIMO/SA multi-antenna systems and thus reduces the channel capacity.