Research On MAC Layer Protocol For Short-range Underwater Acoustic Network

With the rapid development of modern information technology, communication has become an needs of three-dimensional network. Underwater acoustic network has become an integral part of national defense, communications, surveillance, detection.With the development of underwater wireless communications technology, the MAC (Media Access Control) layer protocol for short-range underwater acoustic network is becoming a hot topic in the study.This paper firstly describes the current status of acoustic research network and the progress made in studying the MAC layer protocol. Then we introduce the characteristics of underwater acoustic channel and the challenges we are facing. We also present the issues should be resolved for the MAC layer protocols.We study the MAC layer protocols of short-range underwater acoustic network based on handshake mechanism. And a corresponding OPNET simulation model is built up. We focus on the relationship between network structure and end to end delay, collision rate, bit error rate and throughput. We also study the impact of different RTS (request-to-send) threshold on network performance.Then we put forward a dual-mode MAC layer protocols for short-range acoustic network based on blue-green laser. Blue-green laser is used as the signaling carrier in the protocol, while the ultrasound is used as the data carrier. The stage of signaling interaction is a multi-hop network based on blue-green laser. A three look-up mechanisms is performed to achieve laser signaling forwarding with the established of both adjacent node table and the MAC address forwarding table.