Harmony Search Algorithm Based Threshold-sensitive Energy-Efficient Clustering Protocols for WSNs

摘要

Wireless sensor network (WSN) consists of densely distributed nodes that are deployed to observe and react to events within the sensor field. In WSNs, energy management and network lifetime optimization are major issues in the designing of routing protocols. Clustering is an efficient data gathering technique that effectively reduces the energy consumption by organizing nodes into groups. However, in clustering protocols, cluster heads (CHs) bear additional load for coordinating various activities within the cluster. Improper selection of CHs causes increased energy consumption and also degrades the performance of WSN. Therefore, proper CH selection and their load balancing using efficient routing protocol is a critical aspect for the long run operation of WSN. Clustering a network with proper load balancing is an NP-hard problem. To solve such problems having vast search area, optimization algorithm is the preeminent possible solution. In this paper, harmony search (HS) algorithm based clustering algorithm for WSNs named threshold-sensitive energy-efficient clustering protocol (TECP), is proposed. CHs are selected using HS on the basis of fitness function which is a function of total energy dissipation, cluster cohesion, cluster separation, residual energy of nodes in order to achieve quality clustering and hence to prolong network lifetime. Dual-hop communication between CHs and BS is utilized to achieve load balancing of distant CHs and energy minimization. The paper also considers stability-aware model of TECP named stable TECP (STECP) with an intend to extend the stability period of the network. In STECP, energy aware heuristics is applied for CH selection in order to improve the stability period. The results demonstrate that the proposed protocols significantly outperform existing protocols in terms of energy consumption, system lifetime and stability period.