Lower Bounds on the Capacity of Gaussian Relay Channel
relay channel; capacity; achievable rate
It has been shown recently that the overall throughput of dense wireless networks can increase significantly when wireless nodes collaborate in transmission of different packets. In this paper, we focus on a simple network known as the relay channel, where there is a single relaying node in the system assisting a sender-receiver pair. We present a new achievable rate for the case of Gaussian relay channels, which outperforms the best known schemes in many cases of interest. The proposed scheme is a variation of the amplify and forward method, and is labelled as a scale and forward scheme, signifying that the relay does not use all its power amplifying the received signal. By controlling the scaling and time-correlation of the relay signal, we show that the proposed scheme can outperform all known schemes for several channel gains, especially those where the best known methods provide no improvement over direct transmission. Numerical results are presented to quantify in which regimes the proposed scheme is the best known coding scheme for the Gaussian relay channel.
MetadataShow full item record
- ECE Publications