Performance comparison of 2×2 and 4×4 V-BLAST and Alamouti MIMO systems

In this paper we describe the deployment of a 2×2 and a 4×4 MIMO system using a set of up to eight universal software-defined radio peripherals (USRP) in order to compare the performance of the Alamouti and V-VLAST coding techniques employed for improving the rate and reliability of the data transmission. V-BLAST is based on spatial multiplexing whilst Alamouti employs diversity gain. Results show that, when transmitting M-QAM modulated data, Alamouti achieves a better BER than V-BLAST for the 2×2 as well as for the 4×4 MIMO system.