Cluster Formation by Distance Adjustment with Various Threshold of Wireless Sensor Networks

Wireless sensor networks (WSN) is becoming more and more essential part of human life. In practical applications of WSN, energy saving is one of the most serious tasks. In the clustering method, huge energy disbursed by clusters due to load unbalancing. Too high or too small in size of clusters can create an unbalanced situation. In this paper, we proposed an energy load balancing mechanism that will restrict too low or too large clusters in size. For this reason, we set some threshold value such as upper, lower and ultra-lower. These thresholds value have been set according to the distance between clusters and base station (BS). Cluster size will be varied according to the distance between BS and clusters. Longer distance clusters will be lower in size compare to smaller distance clusters. CHs of longer distance clusters need more energy to send or receive packets to/from BS or other clusters. As we have restricted size of clusters according to distance, so this method will save significant energy. Additionally, one special cluster has been created surrounding BS. Members of the special cluster will communicate directly to BS. We have simulated our protocol using OMNeT ++ simulator and compare with LEACH-C and CH-LEACH and observe significant energy saving in terms of First Node Death (FND), Half Node Death (HND) and Last Node Death (LND); Alive nodes vs. Rounds and Packet send vs. Rounds.