Research On Topology Control For Distributed Wireless Networks

Distributed wireless networks have been extensively used in military and civilian fields due to its characteristics such as low cost,easy deployment and self-organization.The topological structure of network is the physical basis for network nodes to carry out normal communication,and plays a vital role in ensuring reliable end-to-end transmission of the network.Topology control technologies optimize the topological structure of network by means of power control or channel allocation,which can greatly reduce network energy consumption,enhance the connectivity and increase the network capacity.Due to the broadcast nature of wireless channels,distributed wireless networks are susceptible to the influence of external environments.When an interference source appears on an information channel,multiple nodes on the same channel may be unable to work simultaneously,resulting in the fragmented network.At the same time,since the node is energy-constrained,the node cannot work when its energy is exhausted,which brings about the communication interruption,resulting in the fragmented network.Although a variety of schemes to realize a fault tolerance network topology have been proposed in the existing literatures,those schemes only took into account the situation of network node failure or channel failure,and did not solve the problem of the fragmented network caused by failures of both channel and node.In order to solve the above problems,this paper proposes a bi-channel and k-vertex connectivity(BCKVC)algorithm which allows for distributed execution.The network topology constructed by the BCKVC can still guarantee the connectivity when any channel in the network is interfered and any k-1 nodes on other channels fail at the same time,to achieve this goal,the network is at least k+1-vertex connected.This algorithm builds the network topology by jointly power control and channel allocation.First,we employ the power control technology to construct the network topology.During the topology construction process,we ensure that the network has the shortest energy path based on the k+1 vertex connectivity to further reduce the network energy consumption.In addition,we mark the interference nodes for each node during the topology construction process.After constructing the topology,we can obtain the set of interference nodes for each node,which greatly reduces the complexity of the channel allocation to the nodes.Finally,the channel assignment is performed to allocate channels for each node by using the conflict relationship between the nodes.In this paper,firstly the correctness of the algorithm is verified by theoretical analysis.Then analysis of the computation complexity of the algorithm is made,and the message complexity generated by the implementation of the distributed algorithm is provided.Further,simulated analysis of the network performance under different k values is conducted.The simulation results show that on the premise of ensuring bi-channel and k-vertex connectivity of network,the algorithm proposed in this paper can greatly reduce the transmitted power of network nodes and the number of channels required for conflict-free transmission of the network.