Effects of Antenna Spacing on the Performance of MIMO-OFDM with Interference Alignment
15 June 2011
In this paper we have analyzed the performance of multi-cellular MIMO-OFDM system in terms of mean sum rate with respect to different inter element antenna array spacing at the transmitter and the receiver. We have used interference alignment based precoding and compared the performance of different linear receivers to analyze the effects of antenna element separation in a cooperative system. The general notion is that the increase in antenna spacing decreases the correlation thereby increasing the capacity of MIMO system. Our results have shown that the mean sum rate performance in an interference alignment based cooperative multi-cellular system is more influenced by mutual colinearity or mutual correlation of the channels between the cells. To explain this behavior in detail, we have also evaluated different diversity and correlation measures with respect to the antenna spacing. Moreover, we found out that depending upon the antenna configuration of transmitter and receiver pair, the maximum sum rates in the system are achievable around 0.5 spacing.