In wireless sensor networks (WSNs), prolonging the lifetime of a network is the main focus in designing any routing protocol. In this research, the performance of a gateway-based energy-efficient routing protocol (M-GEAR) for Wireless Sensor Networks (WSNs) was observed and analysed. It was realized that, the threshold that was used in selecting cluster heads among the nodes whose distance is beyond the gateway and Base station is on the basis of probability. This allows selection of weak nodes as cluster heads which will not have enough energy to transmit the captured data to the gateway. In this paper, a new reactive gateway-based energy-efficient routing protocol for Wireless Sensor Networks (WSNs) called TEEN-MGEAR (T-MGEAR) is proposed. The new algorithm modified the threshold for selecting cluster heads in M-GEAR by taking into consideration the distance between the nodes and the gateway as well as the residual energy of each node. Furthermore, hard and soft thresholds are implemented in the new scheme to determine when nodes can transmit their sensed data. The performance of the proposed algorithm is evaluated using MatLab 2017a. Simulation results showed that the T-MGEAR protocol outperforms MGEAR protocol in terms of stability period, throughput and network life time.

Keywords : Distance, Residual Energy, T-MGEAR, Gateway, M-GEAR, Wireless Sensor Networks.