Performance analysis of MIMO based multi-user cooperation diversity system using hybrid FDMA-TDMA technique

摘要

User cooperation technique exploits the diversity in wireless networks. In this paper, we have analyzed a hybrid FDMA-TDMA access technique in a cooperative distributive fashion introducing and implementing a modified protocol introduced. We have defined one parameter termed as cooperation gain parameter (CGP) which is the function of transmitter-to-receiver average received signal to noise ratios. Depending on the value of CGP, we decide that whether we proceed with the direct transmission or using the cooperation in consideration. For instance, if value of CGP (G <; 1), the system will undergo the direct transmission and we termed as Power Gain Protocol (PGP) and if (G > 1), the system will be operated in Power and Cooperation Diversity Gain Protocol (PCDGP). Vertical BLAST (Bell Laboratories Layered Space Time) or V-BLAST with minimum mean square error (MMSE) nulling is used at the relays to perfectly detect the joint signals from multiple source terminals. The performance is analyzed using binary phase shift keying (BPSK) modulation scheme and investigated over independent and identical (i.i.d) Rayleigh and Nakagami-m fading environments. Subsequently, simulation results show that the proposed scheme can provide better signal quality of uplink users in a cooperative communication system using hybrid FDMA-TDMA technique.