Distributed Routing and Channel Allocation in Multi-channel Multi-hop Ad Hoc Networks

In this paper, we propose a novel routing protocol which is integrated with channel assignment for multi-channel multi-hop wireless ad hoc networks. In such a network, each node is equipped with three transceivers. One is always tuned on a control channel which is responsible for control and broadcast messages, and the other two perform as transmitter and receiver respectively for traffic flows on different data channels. The routing protocol works in an on-demand manner, and the proposed routing discovery process selects a path that potentially traverses nodes with lighter traffic load and lower number of carried flows. With a given number of non-overlapping channels, the optimal solution of channel allocation for multiple flows is shown to be in general NP-hard. Therefore, a heuristic algorithm for channel allocation based on the information acquired along a flow path is adopted, in order to mitigate two types of interference, i.e., inter-path interference and intra-path interference. NS2 based simulation experiments are conducted to evaluate the performance of the proposed protocol.