Mobile sensor networks consist of a number of sensor nodes which are capable of sensing, processing, communicating and moving. These mobile sensor nodes move around and explore their surrounding areas. Top-k queries are useful in many mobile sensor network applications. However, the mobility of sensor nodes incurs new challenges in addition to the problems of static sensor networks (i.e., resou...

Much work on wireless sensor networks deals with or considers the hot spot problem, i.e., the problem that the sensor nodes closest to the base station are critical for the lifetime of the sensor network because these nodes need to relay more packet than nodes further away from the base station. Since it is often assumed that sensor nodes will become inexpensive, a simple solution to the hot sp...

Wireless sensor networks are embedded networks that are highly restricted to energy, bandwidth and processing power. Even though wireless sensor networks operate with limited resources, sensor nodes are required to do more functions compared to nodes in other data networks. Sensor nodes work as both hosts for processing sensed data and routers for forwarding packets. To decrease such a workload...

Heterogeneous wireless sensor network (heterogeneous WSN) consists of sensor nodes with different ability, such as different computing power and sensing range. Compared with homogeneous WSN, deployment and topology control are more complex in heterogeneous WSN. In this paper, a deployment and topology control method is presented for heterogeneous sensor nodes with different communication and se...

Localization is widely used in Wireless Sensor Networks (WSNs) to identify the current location of the sensor nodes. A WSN consist of thousands of nodes that make the installation of GPS on each sensor node expensive and moreover GPS may not provide exact localization results in an indoor environment. Manually configuring location reference on each sensor node is also not possible for dense net...

Wireless sensor networks have been widely used in many important fields such as target detection and tracking, environmental monitoring, industrial process monitoring etc. Since the nodes in wireless sensor networks consist of a limited power source, energy efficient operations of the nodes are very important. Although energy conservation in communication can be performed in different layers of...

Presently, the developments made in Wireless Sensor Networks are increasing the popularity in several applications like military applications etc. Sensor node localization is a highly desirable capability for wireless sensor network applications. Localization issue is very important, when positions of nodes are not known. In this paper, we make an attempt in localization issue. An efficient and...

Wireless sensor network is collection of sensor nodes and one sink node. Sensor nodes sense the signals and forward to the sink node. In event driven wireless sensor network where some event is happened that event is sense by one of the sensor node and forward to sink node. Sensor nodes are small in size so the energy capacity of sensor node is very less. In the event driven wireless sensor net...

Existing work on placing additional relay nodes in wireless sensor networks to improve network connectivity typically assumes homogeneous wireless sensor nodes with an identical transmission radius. In compare, this paper addresses the problem of deploying relay nodes to provide fault tolerance with higher network connectivity in heterogeneous wireless sensor networks, where sensor nodes have d...

This paper introduce the concept of the energy-efficient Information gathering algorithms for improving lifetime of WSNs and wirelessly recharge the sensor nodes. Here we have assumed that the sensor nodes and base-station are not mobile. The more over location and initial energy of the sensor nodes is known and number of sensor nodes is randomly distributed over a monitoring region. For the he...