Load Balancing to Extend Life of Wireless Sensor Network

Wireless sensor network is energy constrain network. Lifetime of network is defined by life of first certain percentage of dying nodes. Load balancing is a method to make energy consumption of all nodes equal and this way all nodes will die together. By load balancing, lifetime of network does not depend only on life of weak node but depends on life all nodes in network which helpful to increase life of network. In this paper two methods are proposed for load balancing which are also called data aggregation methods. In first method, nodes which are far from the sink consume more energy and load balancing is achieved by increasing the interval of communication based on residual energy of these nodes. In second method, load balancing is achieved by tolerating the quality of data. Nodes which have less energy send data only when data is sufficient deviate from past data. Quality of data is based on deviation control function and this deviation control function is based on residual energy of nodes. Simulation results show proposed methods significantly increases the lifetime of wireless sensor network.