Adaptive Power Allocation in Spatially Correlated Dual-Hop MIMO Relay Channels

Abstract

This paper considers power allocation in a spatially correlated dual-hop multiple-input multiple-output (MIMO) relay channel. In a dual-hop MIMO relay channel, it is desirable to balance the capacity of each hop channel by dynamically allocating the transmit power according to the channel condition. In fact, the end-to-end capacity of a dual-hop relay channel can be maximized by means of max-min optimization with constraint on total power. This paper considers the improvement of the end-toend capacity by allocating the transmit power according to the average channel gain and the spatial correlation between the dualhop MIMO relay channels. Simulation results show that the proposed scheme provides significant performance improvement over the power allocation based on the average signal-to-noise ratio (SNR).