Adaptive power allocation for regenerative relaying with multiple antennas at the destination

We consider a dual-hop regenerative relay system with multiple antennas at the destination. Subject to a total power constraint, we explore adaptive power allocation between the source and relay to minimize the system outage probability and the average symbol error rate. Simulation results show that the presented adaptive power allocation solutions significantly outperform the uniform power allocation. For a fixed relay location, we show that using two destination antennas brings significant power saving and performance improvement over using one destination antenna, and that using more than two destination antennas does not necessarily bring further performance improvement. It is also found that by using more destination antennas and/or choosing an appropriate relay location, less power will be needed at the relay.