English

Capacity of a Class of Diamond Channels

Information Theory 2008-08-08 v1 math.IT

Abstract

We study a special class of diamond channels which was introduced by Schein in 2001. In this special class, each diamond channel consists of a transmitter, a noisy relay, a noiseless relay and a receiver. We prove the capacity of this class of diamond channels by providing an achievable scheme and a converse. The capacity we show is strictly smaller than the cut-set bound. Our result also shows the optimality of a combination of decode-and-forward (DAF) and compress-and-forward (CAF) at the noisy relay node. This is the first example where a combination of DAF and CAF is shown to be capacity achieving. Finally, we note that there exists a duality between this diamond channel coding problem and the Kaspi-Berger source coding problem.

Keywords

Cite

@article{arxiv.0808.0948,
  title  = {Capacity of a Class of Diamond Channels},
  author = {Wei Kang and Sennur Ulukus},
  journal= {arXiv preprint arXiv:0808.0948},
  year   = {2008}
}

Comments

15 pages, 3 figures, submitted to IEEE Trans. on Information Theory