Evaluation of Stable Cluster Head Election (SCHE) Routing Protocol for Wireless Sensor Networks Wan Norsyafizan W.Muhamad, Kaharudin Dimyati, Roslina Mohamad, Rosmalini Abd Kadir Abstract – The nature of wireless sensor networks necessitates specific design requirement, of which energy efficiency is paramount. One of the important parameter in ensuring a good WSN system is the routing protocol. The energy source in WSN is irreplaceable and their lifetime is limited. Thus, an energy efficient routing protocol is inevitable in WSN. This project present the development of an energy efficient routing protocol which consumes significantly less power compared to existing routing protocol for Wireless Sensor Network. The design was developed based on Low Energy Adaptive Clustering Hierarchy (LEACH) routing protocol, intended to reduce the overall energy consumption. Clustering is an energy efficient and scalable way to organize the WSN. The main objective is to minimize the energy dissipation of each sensor node and reduces the energy dissipation for the whole network. Stable Cluster Head Election (SCHE) analyzes the cluster head selection to find the optimal probability of becoming a cluster head. Simulation of Matlab shows that this design reduces communication energy by as much as 95% compared to LEACH, due to stable cluster head election. Keywords: Wireless sensor networks, routing protocol, energy efficiency, clustering. 1. Introduction Recent advances in wireless communication and electronics have enabled the development of low cost, low power, multifunctional sensor nodes that are small in size and able to communicate in short distances. This tiny system, which consists of sensing, data processing and communicating components are known as wireless sensor network [1]. WSN is a collection of sensor nodes organized into a cooperative network. It contains hundreds or thousands of sensor nodes. Each node consists of Wan Norsyafizan W.Muhamad is with Communication Department, Faculty of Electrical Engineering, UiTM., 40450 Shah Alam, Selangor, Malaysia. (email: wnsyafizan@yahoo.com) Kaharudin Dimyati is with Electrical Department, Faculty of Engineering, UM, 50603, Kuala Lumpur, Malaysia. (email: kahar@um.edu.my) Roslina Mohamad is with Communication Department, Faculty of Electrical Engineering, UiTM., 40450 Shah Alam, Selangor, Malaysia. (email: roslina780@salam.uitm.edu.my) Rosmalini Abd Kadir is with Communication Department, Faculty of Electrical Engineering, UiTM., 40450 Shah Alam, Selangor, Malaysia. (email:leeniey79@yahoo.com) processing capability, multiple types of memory, RF transceiver and accommodates various types of sensors and actuators [2]. WSN has limited supply of energy hence an energy conserving routing protocol is important for these networks. Therefore, while conventional networks aim to achieve high quality of service provisions, sensor network focus primarily on power consumption. There are several power-aware routing protocols discussed in the literature [1, 3, 4, 5] and this is also the main target of the work presented in this project. Communication energy conservation can be achieved by limiting the packet size of the data to be sent and by limiting the number of packets that are routed through the network. Computational energy efficiency can be achieved by limiting the number of computational task to be done by a node, in other words making the routing protocol as simple as possible. 2. Energy Analysis of Routing protocols For this project, three existing routing protocols, namely Direct Communication (DC), Minimum Transmission Energy (MTE) and LEACH had been analyzed based on first order radio model [6]. The radio model is illustrated in Figure 1 and the characteristics are summarized in Table 1. Figure 1: First order radio model Table 1: radio characteristics Operation Energy Dissipated Definition of variables E tx-elec E rx-elec (E tx-elec = E rx-elec = E elec ) 50nJ/bit transmitter electronic receiver electronic E amp 100pJ/bit/m 2 transmit amplifier k number of bit message d distance Proceedings of the International MultiConference of Engineers and Computer Scientists 2010 Vol II, IMECS 2010, March 17 - 19, 2010, Hong Kong ISBN: 978-988-18210-4-1 ISSN: 2078-0958 (Print); ISSN: 2078-0966 (Online) IMECS 2010