Energy-Efficient Multi-Level Hierarchical Routing Protocol for Homogeneous Wireless Sensor Network

Wireless Sensor Networks (WSNs) have paved the way for a new arena of monitoring and gathering information. One of the most significant criteria for smooth operation of WSNs is the limited energy supply of the sensor nodes. Numerous elegant energy-efficient routing protocols have been proposed in the literature for solving this problem, e.g. LEACH [1], PEGASIS [2], Hierarchical PEGASIS [3], LEFC [4], CFC [8]. But these protocols seem to suffer from transmission overhead. In this paper we propose Multilevel Hierarchical Routing Protocol (MHRP), a new energy-efficient hierarchical routing protocol, for homogeneous wireless sensor network. Mathematical analysis reveals that Multilevel Hierarchical Routing Protocol (MHRP) outperforms LEACH [1] by 683% longer lifetime for the period when WSN remains fully functionally operational. So far lifetime is concerned MHRP performs equal to that of CFC [8] but it uses 4.26% less energy than CFC [8]. MHRP uses fixed cluster and multiple designated first-level cluster-head (CH) nodes at the center of each cluster. Designated first-level CHs transmit data to the designated second-level CHs located at the center of WSN area. Designated second-level CHs transmit data to the designated third-level CHs located at the nearest position of the base-station within the WSN area. Eventually the third-level CH nodes transmit data to the base-station. In all three levels of designated cluster-head nodes only one node remains in active state and performs the duty of the CH. Rest of the designated cluster-head nodes of each level remain in sleep state and just prior to the death of current CH node of a level, another one from among the designated cluster-head nodes of that level take over the responsibility of the CH. In all three levels of designated cluster-head nodes data is transmitted to the next level CH only after data fusion is done. This scheme reduces transmission overhead and increases the lifetime of the WSN significantly.