Energy efficiency and throughput performance of power and rate allocation on incremental decode-and-forward relaying

In this paper we investigate the combination of rate and power allocation techniques in an orthogonal cooperative scheme using infra-structured (fixed) relays, under the incremental decode-and-forward protocol. We consider realistic large scale and small scale path loss models, taking into account the antennas heights and the presence or not of line-of-sight. Results demonstrate that the throughput performance can be significantly increased in the low signal-to-noise ratio (SNR) region due to rate allocation (RA), and in the high SNR region due to power allocation (PA). In addition, we present an energy efficiency analysis which shows that RA is much more efficient than PA over the whole SNR range.