A Channel Adaptive Energy Efficient and Fair Scheduling Media Access Control Protocol for Mobile AdHoc Networks

Abstract

Problem statement: A major drawback in the existing protocols in dealing with energy management issues is that the time varying nature of the wireless channels among the ad hoc nodes is ignored. Approach: This study proposed a channel adaptive energy efficient Medium Access Control (MAC) protocol, for efficient packets scheduling and queuing in an ad hoc network, with time varying characteristic of wireless channel taken into consideration. Every node in the proposed scheme estimates the channel and link quality for each contending flow based on which a weight value is calculated and propagated using the routing protocol. Since a wireless link with worse channel quality can result in more energy expenditure, the transmission was allowed only for those flows whose weight is greater than Channel Quality Threshold (CQT). For flows with weight less than CQT, the packets were buffered until the channel and link quality recovers or the weight becomes greater than CQT. To avoid buffer overflow and achieve fairness for the poor quality nodes, a fair scheduling and queuing algorithm is designed where in the CQT is adaptively adjusted on basis of the current incoming traffic load. Results: Simulation results showed that the proposed MAC protocol achieves substantial energy savings with better fairness and increased throughput. Conclusion: The designed protocol provided an efficient packets scheduling and queuing in an ad hoc network, with time varying characteristic of wireless channel taken into consideration.