The Study On Capacity For The Antenna Selection Systems In Correlated Channels

Multiple-input multiple-output (MIMO) systems have attracted great interest, since they can improve the channel capacity and reliability of wireless communications. As the need for the large number of the RP, complexity and the cost of the MIMO systems are very large. Antenna selection can solve this problem, antenna selection is proposed as an effective technique to reduce the cost of the implementation of multiple antennas while retain the advantage of MIMO.Since system capacity is one of the most important standards to weight the performance of the wireless communication, it is necessary and significant to solve the expression and closed form of the system capacity. Most traditional analysis for system capacity is under the uncorrelated channels, but in real systems the channel is always correlated, so the researches for the system under the correlated channels are significant. In this paper, all the researches are based on correlated channels.The antenna selection system which we select arbitrary transmit antennas and receive antennas is called general antenna selection system. Due to some unsolved mathematical problems, it is difficult to give the closed form of the capacity for the general antenna selection system. And it is more difficult when the channel is correlated, not only the channel matrix is hard to be calculated but also the correlation matrix is hard to be calculated.In this paper, we investigate the capacity for joint transmit and receive antenna selection systems in spatial correlated channels. As it is hard to give the closed form of the capacity for the antenna selection systems, we focus on the bounds of the capacity. Most traditional analysis for the capacity is based on the processing of the channel matrix, it is very difficult in mathematics. We just deal with the correlation matrix, and then we can get the capacity bounds easily.In this paper we mostly give the analysis for the two types of the antenna selection systems. First we give the capacity bounds for the antenna selection systems that one antenna is selected at the transmitter and any number of antennas are selected at the receiver (This system is called m×1 antenna selection system), and the closed forms of the capacity bounds are given in special systems. Second we give the capacity bounds for the antenna selection system that any number of antennas are selected both at receiver and transmitter (This system is called m x n antenna selection system), and the closed forms of the capacity bounds are also given in special systems.At last we give the simulation to validate our theoretic analysis by MATLAB on computer. The simulation results show that our bounds are very tie with ergodic capacity, and the exact forms of bounds fit the Monte Carlo results exactly.