The use of enhanced clustering techniques and multiple mobile sinks can improve the data-collection efficiency and reduce the energy consumption of wireless sensor networks. Most of the existing approaches use static sinks and multihop routing, which can cause data loss and the early death of sensor nodes, leading to energy-hole problems and inefficient data collection. Nowadays, sensors produce time-sensitive data, and hence, lossy data-collection approaches must be avoided. In order to overcome the aforementioned issues and improve the network lifetime, we propose an enhanced clustering methodology with multiple mobile sinks for efficient data collection. The performance of the proposed method is tested and compared with that of the existing algorithms LEACH, GA, and PSO. The simulation results show that the proposed approach improves the network lifetime significantly and reduces data loss.

Introduction

Sensors are small electronic devices used to monitor or measure changes in real-time environments [1]. They are usually inexpensive and low-power-consuming devices, which are capable of processing and transferring data to a base station. After successful deployment, the sensor nodes form a network, by selforganization, which is called the wireless sensor network (WSN). The primary work of a sensor node is to log the analog information of environmental changes and convert it into digital information with the help of analog-to-digital converters. In addition to logging information, the sensor nodes also act as repeaters to forward the data from other sensor nodes to the base station through single or multihop communication. Generally, the nodes are operated with limited battery resources, and the process of recharging or replacing the battery after deployment is tedious. Thus, the limited lifetime of battery is one of the fundamental issues in WSNs [2–۴]. Sensor technology has various applications, which include industries, automated homes, military applications, modern health care, environmental monitoring, and security, to name a few [5–۹]. In WSNs, information from the sensor nodes is usually transferred to the sink through multihop communication, in order to reduce the energy consumption of the nodes. Though such a data- ∗ Corresponding author. E-mail address: yoonmojung@skku.edu (Y.M. Jung). forwarding approach improves the overall lifetime of the network, it also causes energy-hole problems and the premature death of sensor nodes [10,11]. In particular, with this approach, the sensor nodes close to the sink forward not only their own data to the sink but also the data from their neighboring nodes.