Optimization Of AODV Routing Protocol Under Multi-Rate Circumstance

Along with the development and equipment of portable device, ad hoc networks become a hot question in wireless communication. Ad hoc networks is different from any other networks, it consists of some mobile devices equipped with wireless signal sending and receiving module, which is a temporal and infrastructure system. It can be used in many areas such as battlefield and disaster rescue because of its convenience. Because the node can move anywhere, so the networks topology and links is unstable and varies frequently, it also arise some difficulties in routing technology. Routing technology is also the key problem of widely using of this network, it become the focus of ad hoc networks. This thesis will do research work about two factors in routing protocol implemented, mobility and path metrics.First of all, we proposed life-style–based mobility model based on city section mobility model. Analyze the influences of region which node belongs to and where the node is, it take the VHR and where node is into account, so it make a great step for the reality of world. Considering the location is an important factor in the design of routing protocols, and then we construct a location prediction algorithm under this circumstance, it makes use of the regularity of user's movement.Second, we analyze the defects of AODV routing protocol under multi-rate circumstance, then propose an improving solution using potential throughput capacity metric. The throughput capacity is a metric about the total path throughput between path's lifetimes. So it needs two factors to compute the throughput capacity, one is link's directed stable metric and the other is the capability to sending data. We use the distance between two nodes and the large and small transmission range, to compute the link's directed stable metric. So the path throughput capacity is equal to path stable metric divided by link's sending rate. We hope to use it improve the throughput constraints along many low rate links under multi-rate circumstance. A group of simulations on AODV and AODV-HC show that the protocol using new path metric can improve the throughput and packet delivery rate when high node density.