Research On Clutering Routing Algorithms In Mobile Wireless Sensor Networks

A wireless sensor network (WSN) is a network system consisted of a large number of micro, low-cost and low-power sensor deployed in the observation environment and the sensors are formed by multi-hop communication.Generally, according to the characteristic of mobility of the nodes, mobile sensor network can be divided into two types: the network of all nodes moving and the network of only single or a few nodes moving (such as mobile sinks). The research on the network of all nodes moving, mainly focus on the network of low-speed mobile nodes (such as, M-LEACH), or the network with the characteristics of mobile model (such as LEACH-ME).The mobile sink can be divided into three types: the fixed-line mobility, the random mobility and the autonomous mobility. Because The autonomous mobility can respond to the current network state in time, the main focal point of this paper is how the mobile sinks to autonomously move for effectively prolonging the lifetime of whole network.This paper proposed a MSOL(Mobile Sink Optimal Lifetime) clustering routing algorithm, which integrates mobile sink optimal lifetime theory with the LEACH clustering idea. In each running round of this algorithm, mobile sink only need to collect datum from the designated area and stay in this area for some time, which can ensure optimal to the life of this round. The basic idea of this algorithm is that it firstly transforms time-dependent flow routing into location-dependent flow routing for shrinking the mobile scope of the mobile sink to the smallest enclosing circle A . Then, A is divided into multiple subareas. Each subarea replaces with fictitious cost point that is a N-tuple cost vector, which contains the communication cost from the mobile sink to each node. Lastly, this algorithm computes the optimal location of the sink and the time span of each location by the linear programming (LP) method.This paper elaborates basic steps of MSOL clustering routing algorithm, and designs the data structure and corresponding messages. We simulated this algorithm in order to verify the effectiveness and feasibility of this algorithm. The results show that it makes full use of the advantages of the mobile sinks, which can reduce overhead and significantly prolong the lifetime of network. It can avoid resulting in energy holes problem, i.e."Hot Spot", because of balancing each node's energy.