Effect on performance of wireless uplink for placing decode and forward MIMO relay at different position between source and destination

This paper investigates the effect on performance for placing a decode and forward MIMO relay at different position between source and destination for wireless uplink in the presence of rayleigh fading where source is equipped with single transmit antenna, relay is equipped with multiple transmit and receive antennas, and destination has multiple receive antennas. It is observed that relay at 0.4 and/or 0.5 and/or 0.6 provides best performance. On the other hand, relay at 0.2 and/or 0.8 shows the worst performance. That is, the system shows the best performance placing relay at the middle of the source and the destination, or slightly closer to middle. And the system shows the worse performance placing relay close to the source or the destination. It is also observed that relay at 0.4 or 0.5 or 0.6 provides 5 dB to 12 dB gains at 10^-5 compared to relay at 0.2 or 0.8.