Research On Routing Protocols For Mobile Subnet In Tactical Internet

The mobile subnet in tactical internet chooses the wireless channel as the media and has many characteristics such as agility, mobility, organizing quickly, extending easily, and so on; it is an important part of tactical internet. Mobile subnet will mainly adopt Mobile Ad Hoc Network (MANET) technique in the future. It can set up multi-hop network quickly, adapt well to the changes of topology, and insure the information transmission. The thesis has researched on MANET routings in mobile subnet from different viewpoints, including performance evaluation, energy usefulness, and unidirectional links. Some improved routing and effective schemes are brought forward.The thesis designs a mobile subnet application scene in tactical internet. Some familiar routing protocols in MANET are simulated and evaluated detailedly according to idiographic performance demand in mobile subnet. Some factors that influence the performance of mobile subnet such as bandwidth, speed, and coverage area is analyzed and summarized. At last some correlative suggestions about designing mobile wireless subnet are given.Aiming at the energy conserving need of mobile wireless subnet, this thesis studies the routing protocols from the energy usefulness. For the individual node, a cross-layer power-controlled routing protocol that needn't the help of geographical position information is designed based on symmetry of channel gain and AODV protocol. Simulation shows that the improved protocol has good effect on saving power and doesn't impair the performance. For the whole network, load balancing of the network must be considered. The thesis detailedly evaluates the performance of multipath routing protocols for the purpose of load balancing. Then, an improved transmitting scheme of load balancing is brought forward. The simulation shows that the scheme increases the throughput of TCP protocol.The radios'coverage area is usually different in battlefield and there are many unidirectional links, so routing protocols in mobile subnet must support unidirectional links. Several techniques that fit for reactive routing protocols to solve unidirectional problems such as blacklist, reverse path search and EUDA are introduced and analyzed. A blacklist mixed with reverse path search method is designed. Simulation shows that this method evidently increases the packet delivery ratio and has superiority compared with blacklist and reverse path search.