Research On Energy-saving Routing Protocols For Wireless Ad Hoc Network

Mobile self-organization network (MANET) is a kind of wireless network, which doesn't need the support of fixed infrastructure and can be organized flexibly and fastly. The nodes in the network not only have the functions of common terminal but also have the routing functions and are able to move freely. It have strong anti-destroying ability and can survived under extremely difficult circumstances like in battleground, emergency relief and other occasions, so it has been widely applied in the military and civilian communication fields. The routing protocols used in traditional wired network are not suitable for Ad Hoc network, as it have the characteristics of distributed, self-organization, dynamic topology, multiple hops, energy limited and so on. Thus we should design and develop new protocols specially for Ad Hoc networks.Routing technology as one of the key factors that influence network performances, the research of it is also crucial and important for Ad Hoc network. The typical routing protocols such as DSDV,AODV,DSR,TORA presented by now are all shortest routing, which do not consider the energy aware factor. However, the nodes in Ad Hoc networks are batteries operated and the energy of the network system is limited. How to reduce the nodes'energy consume and prolong the lifetime of the network is becoming an important indicator on evaluating the performance of routing protocols. The energy conservation appears especially important in the situations such as emergency rescue, military action and business conference where the time and the devices is constrained. So the routing protocol based on energy-saving mechanism is becoming the current research focus of Ad Hoc network.In response to the above problems, to address the shortcomings of traditional routing protocols, this paper studied the energy problem of Ad Hoc networks. First, we make a brief introduction about mobile Ad Hoc network, including the characteristics, applicated domains and the research meanings of this thesis, and then summarize some routing protocols that were already proposed for Ad Hoc network,analyze and compare their advantages and disadvantages, at last, we sum up the existing energy-saving mechanisms and indicates their future research directions.Based on the study of current routing algorithms and energy-saving mechanism, two new energy aware routing algorithms MEE-AODV(Maximum energy efficiency-AODV) and ES-AODV(Energy-saving-AODV) were proposed in this paper. The former by improving the processing procedure of RREQ packet without using any additional control packets can acquire the average residual battery level of the entire network and it compromises between the number of hops and node residual battery energy to achieve the purpose of energy saving. The latter through the link layer power control, making the node carry the power of information in the sended data packets to complete the information interaction. Finally, we compare them with traditional routing protocols through the NS2 simulation, the results show that the new mechanisms work well in energy reduction and prolong the network lifetime so it improves the network performance efficiently.