Rate-adaptive MAC protocol for efficient use of channel resource in wireless multi-hop networks

In wireless networks, resource allocation and management are very important research issues because nodes share same medium for their transmission. We propose a rate adaptive MAC protocol that nodes dynamically adjust the transmission rate according to wireless link state to increase the throughput of overall network in data link layer. In general cases, wireless nodes may use TCP protocol for end-to-end flow control in upper layer. It is difficult for an end node to control the end-to-end traffic rate in only datalink layer. In this paper, the Rate adaptive MAC protocol is able to adapt traffic rate without information of flow ID which is decided in the transport layer. This protocol connects with network layer using cross layer approach, and it operates in datalink layer independently. Wireless nodes can communicate using suitable data rate when wireless channel status changes as time or location. Proposed method prevents the waste of channel resource, and improves the average throughput of whole network. We suggest a method of end-to-end flow control in the MAC protocol, and prove the performance of our proposed mechanism by simulations.