Distributed Multiple Access and Flow Control for Wireless Network Coding

In this paper we propose network coding to perform multi-hop multicast wireless transmissions. More specifically, we address the problem of reducing redundancy in the completely distributed operation of network coding, so as to increase network throughput. In order to do so, we propose a distributed system where network nodes autonomously make decisions with respect to the packets to encode and forward, with the goal of maximizing the data detection probability and minimizing the overhead of transmitted packets. Our setup consists of a Slotted Aloha network where nodes inject packets at a rate which depends on how useful these packets are to other nodes. We model the selection of transmission probabilities by means of a game theoretic approach, in which nodes reach the desired transmission probabilities as an equilibrium solution to the game. Simulation results show that the proposed scheme outperforms a Slotted Aloha system with optimal uniform retransmission probability.