Adaptive channel allocation strategy for mobile ad hoc networks

Medium access control (MAC) protocol is essential since it is to address how to resolve potential contentions and collisions among wireless nodes and give them equal share of channel bandwidth. However, due to the existence of hidden/exposed terminal problem and partially connected network topology, IEEE 802.11 standard, the de facto and widely accepted wireless MAC protocol, does not function well in mobile ad hoc networks (MANETs) because it brings intensive collisions, unfair channel access, and quickly degraded system throughput in multi-hop environments, especially when the whole system is also dense and congested. One approach to alleviate this problem is to use multi-channel MAC protocol because these nodes can access the wireless channel simultaneously as long as they choose the different channels to transmit their packets. Nowadays, the modern wireless MAC protocols usually support multiple channels, where mobile nodes adapt their channels based on their channel selection strategies to transmit their own packets. In this paper, we put forth an adaptive channel allocation strategy for IEEE 802.11 based multi-channel MAC protocol in MANETs. An analytic model is also carried out to study the normalized saturation throughput of proposed scheme. In addition to theoretical analysis, simulations are conducted to evaluate the performance of the proposed scheme in congested multi-hop environments, and the results indicate that our adaptive channel allocation strategy did achieve far better performance than the legacy single channel IEEE 802.11 protocol without loss of simplicity.