Joint Beamforming with Speed Sensitive Relay Selection for Future Wireless Generation MIMO Networks

Abstract

Future wireless generation networks using MIMO systems have wide demand on transmission speed, coverage range and signal quality. The traditional joint beamforming (JBF) approaches are carried out concurrently at relay and receiver nodes. The existing beamforming (BF) architectures are computationally complex and the communication system lacks an efficient relay selection scheme. The problem becomes severe for dynamic and fast moving communication nodes. This paper proposes a novel JBF architecture with relay selection to mitigate the effects of time delay in BF matrix update in a dynamic mobile environment. Relay switching is carried out based on sensing the speed of mobile nodes. Switching phase is bypassed and BF continues with the selected relay if the mobile nodes are static or mobility is negligible. For dynamic environment, it is necessary to update BF matrix after each time when new set of relays are selected. Minimum Mean Square Error algorithm is used for BF vector calculation and Hybrid Cuckoo Search Optimization algorithm is used for speed sensitive relay selection. The proposed JBF algorithm outperforms well in terms of weighted sum rate and Sum of Mean Square Error along with guaranteed time delay for beam steering. The proposed hybrid optimized solution for speed sensitive relay selection with JBF is best suitable for next generation wireless networks.