Low complexity algorithms for transmit antenna selection in cognitive MIMO system

Cognitive radio (CR) enabling dynamic utilization of spectrum white spaces is considered as a key technology to improve spectrum utilization efficiency, where cognitive users can avail unused radio frequency (RF) spectrum on secondary basis while not unduly interfering with the legitimate users. Multiple antenna techniques, promising diversity and capacity gains may also be an efficient solution to combat interference in such co-existing environments. However, additional system cost and complexities associated with multiple antennas limit their application in CR systems. We propose low complexity antenna selection algorithms, which greatly reduce hardware cost and complexities of cognitive MIMO system, while keeping much of the benefits of the multiple antennas. Simulations results verify that proposed algorithms achieve near optimal system capacity over a wide range of SNR, while adhering interference constraints to the primary users.