Int. Journal of Engineering Research and Applications www.ijera.com ISSN : 2248-9622, Vol. 4, Issue 6( Version 3), June 2014, pp.150-153 www.ijera.com 150 | Page Network Life Enhancement in Wireless Sensor Network Anjali*, Saurabh Mittal** *( M. Tech Student, Department of Computer Science, Galaxy Global Imperial Technical Campus, Ambala, Haryana, India) ** (Associate Professor, Department of Computer Science, Galaxy Global Imperial Technical Campus, Ambala, Haryana, India) ABSTRACT In Wireless Sensor Network the main focus is on developing a mechanism to extend the network lifetime by energy balancing. To achieve this, LEACH (Low Energy Adaptive Clustering Hierarchical) protocol and LEACH-CC (Leach-Centralized with Chain) protocol is used. But LEACH and LEACH-CC have some limitations that are overcome by Group based routing protocol which is presented in this paper. In this study the nodes are grouped into one group that lies in the same range which senses the similar data from the field in which nodes are deployed in. Each group has only one active node for sensing the data and others are at sleep mode which increases the lifetime of network by saving the energy used in transmitting the duplicate data. Two base station locations are used to overcome the hotspot problem and to reduce the distance problem. The results shows that Group based routing protocol perform better than LEACH and LEACH-CC and extend the lifetime of network. Keywords: Base station, LEACH, LEACH-CC, Threshold energy, Sensor Node, Wireless sensor network I. Introduction A Wireless Sensor Network is a collection of micro sensor nodes organized into a cooperative network. Typically, a large number of nodes are randomly deployed within a geographic area. The basic functionality of the sensor nodes are data sensing, data processing and communication with other nodes or base station. To perform these operations the sensor nodes need to have a power supply (usually a battery), which has a limited lifetime. These nodes may be deployed in an unpractical environment where it would be impossible or inconvenient to recharge the battery. These nodes are used in multiple areas such as military area for battlefield mapping and target surveillance, area monitoring, health care etc. Energy is a major concern in WSN. As sensor nodes are constrained with battery powered, the energy usage has to be carefully managed in order to prolong the lifetime of the system. II. Low Energy Adaptive Clustering Hierarchical Protocol (LEACH) W. R Heinzeolman proposed LEACH protocol [1], which is based on cluster structure and hierarchical technology. LEACH is a self-organizing, adaptive clustering protocol that uses randomization to distribute the energy load evenly among the sensors in the network. The operation of LEACH is broken into rounds and each round has two phases: set-up phase and steady phase. In set-up phase, the clusters are formed; in steady phase, data is transfer. When clusters are created, each node decides whether or not to become a cluster head (CH) for the current round. This decision is made by the node “n” choosing a random number between 0 and 1. If the number is less than a threshold, the node becomes a CH for the current round. The threshold value is calculated based on an equation1: T(n)= P / (1-P*(r*mod1/P)) if nG …. (1) Where P = the desired percentage of CHs (e.g. P=0.05), r= the current round, and G is the set of nodes that have not been selected as a CH in the last (1/P) rounds [1]. Using this threshold, each node will be a CH at some point within 1/P rounds. During first round, each node has a probability P of becoming a CH. The nodes that are CHs in first round cannot be CHs for the next 1/P rounds. Thus, the probability that the remaining nodes are CHs would increase, since there are fewer nodes that are eligible to become CHs. After 1/P rounds, all nodes are once again eligible to become CHs. LEACH assumes that all nodes are in range of wireless transmission of the base station which is not the case in many sensor deployments. Around 5% of the total nodes play as CHs in every round [2]. The shortcomings in LEACH are: 1. The CH node is randomly selected. After several rounds, the node with more remaining energy and the node with less remaining energy have same probability to select as CH [2]. If the node which has less energy is selected as CH, it will drain out energy and die quickly in short time, so RESEARCH ARTICLE OPEN ACCESS