A Study On Topology Control-based WSN Data Gathering Protocol

Wireless Sensor Network is a new cross-disciplinary field. It has promising prospects in fields like military affairs, transportation, environmental protection, construction as well as intellectual space. It is also the focus of many researchers. The realization of WSN is indispensable to the reliable data gathering mechanism. Owing to its seriously limited energy, WSN utilizes topology to exploit energy to the fullest potential. Effective topology is able to save energy, cut down delay and improve the reliability of data gathering. Hence, it is very necessary to study the data gathering mechanism based on topology. PEGASIS, a representative of the data gathering mechanism, applies the simple chain to optimize energy, it can't solve the problem of energy-efficiency, delay and reliability. My thesis will focus on the data gathering protocol by means of topology.In view of the disadvantage of delay that occurs when all the nodes transmit along the simple chain, the thesis comes up with the hierarchy topology structure. First the nodes are grouped according to their distance from SINK. The main chain is built within the nodes nearest to SINK, and then nodes farthest from SINK make up the sub-chains.It decomposit the flow and delay of PEGASIS efficiently.In order to improve the reliability of data gathering, the thesis comes up with TC-RDGP, a reliable data gathering protocol based on topology. TC-RDGP applies topology twice when gathering data, activates the one-hop sleeping nodes on the main chain, finds out monitors within the main chain by means of weight function value and MVSC. In this way, the monitoring and recovery of data loss can be realized in the process of data transmission, and the reliability of data gathering can be ensured. By setting up network modules and simulating TC-RDGP with NS2, the result shows that TC-RDGP has much more obvious advantages than DD and PEGASIS in aspects of energy-efficiency, delay and reliability.