A wireless sensor network is active research area with various workshops and conferences arranged each year. A Wireless Sensor Network (WSN) is a set of hundreds or thousands of micro sensor nodes that have capabilities of sensing and establishing wireless communication between each other and doing computational and processing operations.
Sensor networks have different applications and systems with changeable requirements and characteristics. The sensor networks can be used in Military environment, Disaster management, Habitat monitoring, Medical and health care, Industrial fields, Home networks, detecting chemical, Biological, radiological, nuclear and explosive material. Deployment of a sensor network in these applications can be in arbitrary fashion (e.g. dropped from an airplane) or can be planted manually (e.g. fire alarm sensors in a facility). For example, in a disaster management application, a large number of sensors can be dropped from a helicopter. Networking these sensors can assist rescue operations by locating survivors, identifying risky areas and making the rescue team more aware of the overall situation in the disaster area.
Wireless sensor networks consist of spatially distributed sensor to monitor physical or environmental conditions and cooperatively pass their data to a central location. These kinds of network have come into prominence because they hold the potential to revolutionize many segments of our life from environmental monitoring and conservation to automation in traffic monitoring and health-care business. The design, implementation and operation of a sensor network require the assemblage of various disciplines including embedded systems, hardware, networking, information management and distributed algorithms.
There are four building blocks of a wireless sensor network:
1. A central location for gathering information.
2. Set of nodes which collect information through sensors and transmit to its neighboring nodes or to the central location.
3. A wireless network.
4. Cluster of computing resources to data correlation, data mining purposes, etc.
Functional Architecture of a Wireless Sensor Network the darkened circles represent the nodes
Since energy consumption plays an important role in WSNs, energy efficiency and load balancing are significant challenges of routing algorithms in WSNs. In this write-up an energy efficient routing algorithm for WSNs has been proposed which considers sensor nodes current energy, sensor nodes position and the number of neighbours of sensor nodes in the selection of CH nodes. By collection of sensor nodes that have more residual energy and also have relatively little distance for being CH node, as well as by tacking into account the distance of CH nodes from the BS factor in the cluster formation phase.
1) the average energy consumption of the WSN is reduced and
2) the WSN lifetime is extended as compared to LEACH, DBS and LEACH-C algorithms.
Simulation results support that the I-LEACH algorithm has the flexibility of changing the position of BS in WSN.
I-LEACH selects a node with higher residual energy, many number of neighbor and smaller distance to the BS as CH node. Based on the CH formation, all the sensor nodes manage to form the clusters in a way to maximize WSN lifetime and minimize average energy dissipation per each sensor node. Using MATLAB simulator, I-LEACH algorithm is simulated and the concert is compared with algorithms such as LEACH, DBS and LEACH-C algorithms. Results proved that I-LEACH improve the performance at least 65%, decreases the consumption of energy up to 62% and improves the PDR successfully by at least 56% as compared to the these algorithms for WSN.
