Wireless Sensor Nodes : An Emerging Key Technology Of 21 ' St Century

A WSN is a type of wireless networks that consists of collection sensor nodes which are tiny devices. Each sensor node of the network has different processing capability. It may contain multiple types of memory (program, data and flash memories), have a RF transceiver, have a power source (e.g., batteries and solar cells), and accommodate various sensors and actuators. The nodes communicate wirelessly and often self-organize after being deployed in an ad hoc fashion [13, 14]. Optimum need of each sensor node is to maximize its own utility function. Also the whole network requires resource assignments balance to perform in a useful and efficient way. This chapter presents a brief survey on WSNs showing its types, characterizing features, protocols and applications.

A Wireless Sensor Network is one kind of wireless network includes a large number of circulating, self-directed, minute, low powered devices named sensor nodes called motes. These networks certainly cover a huge number of spatially distributed, little, battery-operated, embedded devices that are networked to caringly collect, process, and transfer data to the operators, and it has controlled the capabilities of computing & processing. Nodes are the tiny computers, which work jointly to form the networks. The sensor node is a multi-functional, energy efficient wireless device. The applications of motes in industrial are widespread. A collection of sensor nodes collects the data from the surroundings to achieve specific

The sensor nodes in a Wireless Sensor Network (WSN) are used for surveillance of ambient environment, which can be unpredictable. The sensor nodes are often exposed to harsh surroundings, which could lead to many problems like failure of the sensing unit, radio transceiver, and processors; not just that, also sensor node death occurs due to energy crunch eventually. So it’s understood that faults directly affect the network lifetime of a Wireless Sensor Network. Wireless Sensor Network Lifetime means the time period required for the network to function with the collective effort of sensors even if some of the nodes have failed. When this percentage of failed nodes increases, fault prevention and avoidance strategies are needed to be applied to improve reliability and performance of the network. A reliable WSN yields accurate results. For fault tolerance in WSN, maintenance of a consistent quality of service (QoS) is necessary. Also energy efficiency comes into picture, which is a difficult task to achieve.

This paper is also proposed a frame work for the simulation of the wireless sensor networks and the applications of WSN are that proposed an algorithm. The applications of wireless sensor networks is spreading rapidly form the last ten years in many areas like mostly in the areas called militaries, defence, large buildings, industries, and in many commercial buildings. Due to the advancement in wireless sensor networks the sensors with low power and the modules equipped with radio devices is now replaced with the wired sensors. These small modules (tiny) can be known as motes will collect all the information from the environment by using the motes and is also working like neurons.

A Wireless Sensor Network or WSN is supposed to be made up of a large number of sensors and at least one base station. The sensors are autonomous small devices with several constraints like the battery power, computation capacity, communication range and memory. They also are supplied with transceivers to gather information from its environment and pass it on up to a certain base station, where the measured parameters can be stored and available for the end user.

The wireless sensor network is applicable in numerous life saving critical field because of low cost long battery life sensors. A sensor network comprises of sensors and routers to choose the administrator host that is called the coordinator [2]. A wireless sensor network is easy to use in the desired environment [6], and the information can be collected then processed and sent to a desired location. Recent break trough in wireless communication and micro-electro-mechanical systems (MEMS) [3-5] provides large scale, low power, multi-functional, and low cost network

Wireless sensor networks typically consist of a large number of sensor nodes with limited onboard battery resources which are difficult to recharge or replace. Thus the reduction of energy consumption for end-to-end data rate and maximization of network lifetime have become chief research concern. In recent years, many techniques have been proposed for improving the energy efficiency in wireless sensor networks. Among these techniques, V-MIMO technique has been considered as one of the effective ways to save energy. In WSN a node has two communication related energy consuming roles, one role is to serve as a packet generating source node (SN), and the other role is to relay packets for the other nodes, which are both energy consuming operations. This is why the energy minimization is required to extend the lifetime of the WSN.

The ideal wireless sensor is networked and scalable, consumes very little power, is smart and software programmable, efficient for fast data acquisition, reliable and accurate over the long term, costs little to purchase and install, and requires no real maintenance.

Wireless sensor nodes consists of three pars first one is wireless means without wires second one is sensor mean our nodes or data sensing process third and last one is networks means connection of these nodes to form a network to communicate and report data. When we concern its quality of service it may become too wide part of research so we are promised to work only in energy efficient protocols. The reason behind wireless

There is a number of power reduction practices must be used both in the design of the circuits and in the design of network protocols approaches . The major step towards reduced power consumption is a sound electronic design [32],[34] selecting the efficient circuits and applying suitable design procedure to each case. Sometimes the most important causes of energy depletion in the WSN node is the idle mode consumption, when the node is not initiate any communication but listening and waiting for information from other nodes. Energy loss due to packet collision is also a major issue, causes all data packets involved in the transmission are discarded and must be retransmitted . Another cause of energy loss is the wrong routing leads to the reception of packets to non addressed node. Next major source of energy loss is the transmission and possible retransmission of control packets, as these can be seen as protocol overhead[26]

In computer science, wireless sensor networks are an active research area with numerous workshops and conferences arranged each year.

Wireless Sensor Networks are formed by autonomous nodes containing partial memory, better range of communication, power and capable bandwidth. WSN are used to inspect the corporal and environmental conditions through a system and perform data processing. However, during data acquisition different types of issues and circumstances are to be resolved.

Energy Consumption: Sensor Nodes are subject to battery power. Sensor networks are set on hostile situations so supplanting the battery is unfeasible. Consequently energy preservation and administration is a basic issue to determine in wireless sensor network.

A number of studies and researches showing the improvement in LEACH protocol of Wireless Sensor Networks.

ABSTRACT: Wireless sensor networks is a self-configured network means any node can join it or leave it at any time. it is a self-healing and self-organizing. Self-healing networks allow nodes to reconfigure their link associations and find other pathways around powered-down nodes or failed nodes. Self-organizing allows a network automatically join new node without the need for manual interference. In this paper, we are using actor nodes to solve energy hole problem so that we can reduce energy consumption and can enhance throughput of network.