A Research On Underwater Acoustic Sensor Network Routing Based On Geographical Location

Underwater acoustic sensor networks(UASNs) are new research hotspot, recently, become more and more popular cause by researchers. As a kind of intelligent networks application system, it integrates data collection, data transmission and other functions. It is because of their advantages that make the UASNs have a broad prospect in civilian and military use.In this article, first introduce the characteristics of underwater acoustic channel in UASNs, The networks' own characteristics, the structure of the system and describe the challenges and potential applications. At the same time, highlighting the current development of the location-based routing protocol in underwater acoustic sensor network routing protocols, and select some relatively typical routing protocols to describe in detail and classify the routing protocols according to the characteristics of themselves. Finally, compare and analyze the listed routing protocols.1. The proposed ABGR(Advanced Basic Geographic Routing) routing protocol. For the BGR protocol when in the selection of the next hop, there is a repeate adjustment node transmission radius problem and the interference of the neighbor nodes of the candidate node in the selection of the next hop forwarding node problem. This paper proposes a more efficient routing protocol- ABGR. ABGR routing protocol first judgment whether the sink node is within the forwarding node's transmission range or the neighbor nodes' transmission range, if so, then pass directly to the Sink node or the neighbor node; otherwise, according to the value of the candidate nodes on the forwarding node and sink node connection of projection, select the nearest neighbor node to the Sink node as the next-hop forwarding node. Repeat the process, until the packet transmitted to the Sink node. Through these new mechanisms, the protocol can decrease the interference factors and send the packet to the Sink node with the least time, which reduce the network's delay and the packet overhead, increase network's throughput. Theoretical analysis and simulation results show that compare with the original protocol BGR, the performances indicators of transfer data rate, the network's throughput and others are indeed further improved by the ABGR routing protocol.2. For the original GEDAR routing protocol has the problem that did not consider the closest neighbor node as the next appropriate hop to the Sink, as well as the problem when face with the routing void, ignore the method by floating the node in the hole when the distance to the Sink node is within a reasonable range. This paper proposes an improved routing protocol IGDAR(Improved GEDAR). In the routing protocol when select the next hop according to the priority of the neighbor nodes by the distance from the neighbor nodes to the forwarding nodes and to the sink node, the smaller the sum of the two distances, the greater the priority; then, the subnet of the neighbor nodes will be divided according to the prioritization. In the problem of routing void, when the distance from the node in the routing void to Sink node is within two transmissions radius, the node use the float operation that can directly transmission the packet to the Sink node. Through these new mechanisms can elimination the circuitous path in the transfer process, reduce the average transmission delay and increase the approach to transfer the packet out of the routing void area. The simulation results show that the IGDAR has a better performance on selecting candidate nodes and solving routing void than the original one.Finally, the summary and the future research direction of the underwater acoustic sensor networks based on geographical location routing protocols are given.