Research On Topology Control Of Wireless Ad Hoc

A significant feature of wireless Ad Hoc networks is rapid change in topology, which introduces great challenge to network connectivity. So it makes sense to design a connected wireless Ad Hoc networks and to maintain its connectivity during a later time.Critical nodes, whose removal or failure will disconnect network into two or more separate components, are the bottleneck of network connectivity. Based on the definition of critical nodes and a comprehensible concept (elementary loop) introduced by this paper, a basic property of critical nodes is found and then an algorithm to detect them was proposed with detailed description of each step. Simulation results indicate that the proposed algorithm can detect critical nodes reliably with low cost.In this paper, wireless distributed network with spectrum sensing ability was studied; a novel topology control algorithm was proposed to achieve the objectives of network connectivity and residual energy. The details of the algorithm were described, and by simulations under OPNET, our algorithm obtained good performance.At last, we did some research on network coding, especial focus on the application of network coding in wireless networks. We discussed the maximum flow problem considering broadcast channels with emphasis.