Research On The Technology Of Topology Control In Mobile Ad Hoc Networks

Mobile Ad Hoc network is a wireless communication network composed of nodesof a group of wireless communication devices equipped with networking capabilitywithout the need for cable infrastructure, and in most cases, it supports mobilecommunication. It is precisely because of the characteristics of mobile Ad Hoc networks,which made this type of networks widely used in military, commercial, medical, familyor other civil occasions. But with the increasing diversity of node and the mobileterminal in the network, to improve the performance of the network must be consideredin many aspects such as transport protocols, routing protocols and topology control.Topology control for mobile Ad Hoc networks is mainly based on the nodetransmission range adjustment, constructing the network topology structure with someglobal characteristics, in order to reduce the energy consumption of nodes etc… Basedon the study of the existing topology control algorithm, we analyze the topology controlfrom the aspects of network survivability, link quality, and reliability etc… This papermainly has the following several aspects of work:First, we overview the characteristics of mobile Ad Hoc networks, and analyze thedefinition, goal and means of topology control algorithm, then compare somecharacteristics of several typical algorithms and point out the problems andshortcomings of these existing algorithm.Second, for the Ad Hoc networks whose network topology changes slowly,considering the impact of transmission power on network connectivity and link quality,we design a centralized topology control algorithm NCTC based on natural connectivity.Each node gradually increase the transmitting power from the minimum transmissionpower to maximum transmission power, then according to the link quality of thetopological graph adjacency matrix, the NCTC algorithm calculates the weightednatural connectivity, which is a characterization of the comprehensive index of networksurvivability and link reliability, and draw a curve of the change trend of the weightednatural connectivity with the change of transmission power. From the curve, we canobtain the best transmission power of a given network with the guarantee of network connectivity conditions.Third, for the Ad Hoc networks whose network topology changes quickly, based onlink quality perception, we propose a distributed topology control algorithm LP-LTRT,which only needs the link state information of the local topology. Based on Hellomessage interaction, we can get the current link quality information of the localtopology, and then we implement the LTRT algorithm to construct a local logicaltopology, which can guarantee the network k-edge connected.