Institute of Electrical & Electronic Engineers
The authors consider the problem of network coding across three unicast sessions over a directed acyclic graph. They consider a SISO scenario, in the sense that each source and receiver is connected to the network through a single edge. They adapt a pre-coding-based interference alignment technique, originally developed for the wireless interference channel, to the network setting. They refer to this approach as Pre-coding-Based Network Alignment (PBNA). Similarly to the wireless setting, PBNA asymptotically achieves half the minimum cut. Different from the wireless setting, network topology may introduce dependencies between elements of the transfer matrix, which they refer to as coupling relations, and can potentially make PBNA infeasible.