Relay Nodes: Enhancing Network Lifetime and Throughput in Wireless Sensor Networks

Recent advances and researches in field of WSN have enabled the development of low -cost, low-power, multifunctional sensor nodes having functionalities such as self-organizing, data processing & aggregation etc. As these sensors are batteryoperated, so it is very crucial to use this limited energy in an efficient way. Node mobility factor gave rise to sensor networks that have many potential applicat ions now days. In this paper, we have observed the phenomenon of unequal energy depletion rates within sensor nodes which lead to the “Energy Hole” problem in many-to-one WSNs. Each node routes the sensed data to the sink which depends upon the network infrastructure i.e. single-hop or mult i-hop arch itecture. Each node consumes the more energy in communicat ing and in finding an optimal route for data transmission to the sink or base station. Due to the fact, nodes which are placed close to the sink drain their energy soon because they have to transmit the data gathered from the whole network and as well as their own sensed data up to the base station. As a result, these nodes may become isolate from the network leaving a “Hole” in the network. Th is hole or a connectivity gap causes the early dysfunction of whole network. To avoid this problem, we have incorporated some additional nodes called as Relay Nodes in the nearby region of sink. In this scheme, we have implemented an energy efficient clustering & routing protocol LEACH supporting node mobility. Clustering is handled by base station. Imposed relay nodes will relay the data generated by the network up to sink and maintain the balanced energy consumption and load balance across the network. Simula t ion results validates the proposed methodology in terms of performance metrics such as energy efficiency, high throughput and less packet delay resulting in enhanced overall network lifetime and connectivity.