Capacity of a Class of Linear Binary Field Multi-source Relay Networks

Abstract

Characterizing the capacity region of multi-source wireless relay networks is one of the fundamental issues in network information theory. The problem is, however, quite challenging due to inter-user interference when there exist multiple source--destination (S--D) pairs in the network. By focusing on a special class of networks, we show that the capacity can be found. Namely, we study a layered linear binary field network with time-varying channels, which is a simplified model reflecting broadcast, interference, and fading natures of wireless communications. We observe that fading can play an important role in mitigating inter-user interference effectively for both single-hop and multi-hop networks. We propose new encoding and relaying schemes with randomized channel pairing, which exploit such channel variations, and derive their achievable rates. By comparing them with the cut-set upper bound, the capacity region of single-hop networks and the sum capacity of multi-hop networks can be characterized for some classes of channel distributions and network topologies. For these classes, we show that the capacity region or sum capacity can be interpreted as the max-flow min-cut theorem.

19 pages, 7 figures, submitted to IEEE trans. on Information Theory

References in corpus (7)

• The Approximate Capacity of the Many-to-One and One-to-Many Gaussian Interference Channels
• Approximate Capacity of Gaussian Relay Networks
• Multiple Access Outerbounds and the Inseparability of Parallel Interference Channels
• Ergodic Interference Alignment
• Approximate capacity of the two-way relay channel: A deterministic approach
• Transmission Techniques for Relay-Interference Networks
• On Models of Multi-user Gaussian Channels with Fading