Heterogeneous Ad Hoc Network Access Protocols And Routing Policy Research

Heterogeneous networks and self-organized networks are hot research topics in current computer networks study. However, Heterogeneous Ad Hoc Networks combines the two features together, which makes it the main object of the future network technologies study. It shall be the trend of the next generation network. Among all related technologies, MAC protocols and multi-hop routing strategy are the key technologies.Under such a background, a range of existing technologies for Heterogeneous Ad Hoc Network and the main problems faced are discussed in this thesis. In the study of MAC protocols, key problems like hidden node problem, exposed node problem etc. are all well analyzed. Then, refer to the specialties of Heterogeneous Ad Hoc Network, an improved MAC protocol which is based on the802.11DCF and MARCH protocols, is introduced. The simulation of the new protocol is done and its results are compared with the performance of802.11DCF。Meanwhile, in the study of routing strategy, a new comprehensive multi-hop routing is introduced, which absorbs the advantages of both active routing strategies and on-demand routing strategies. It is also simulated in Matlab.At last, cross-layer design is used to combine the previous improved MAC protocol and routing strategy. The "Hello’" packets for routing maintenance are managed to be replaced by the control frames in MAC protocol, which may improve the performance of the entire network.