Joint Shortest Chain and Fair Transmission Design for Energy-Balanced PEGASIS in WSNs

The conventional routing protocol considers several local transmission factors in a single node for the many-to-one packet transmission. These factors lead to rapid energy consumption in some specific nodes, thereby generating energy holes to reduce network lifetime. In this paper, a novel energy-balanced power-efficient gathering in sensor information systems (EB-PEGASIS) is proposed to improve energy efficiency and utilization for wireless sensor networks (WSNs). In the original PEGASIS, the protocol constructs a chain-based network with the locally shortest distance rather than the globally optimal network length. To improve this, two construction algorithms are proposed to achieve the shortest network length in the EB-PEGASIS, including centralized formation and distributed construction schemes. In the centralized algorithm, the chain length of each starting node is computed, and the minimum chain length can be subsequently determined in the following packet transmission phase. In order to reduce formation complexity, a distributed method uses the K-means clustering algorithm to partition the network into clusters. In particular, it forms a sub-chain in each cluster and connects each sub-chain into the final shortest chain. Additionally, to balance the energy consumption among all nodes in the packet transmission phase, a Jain’s fairness index for residual battery capacity is designed to minimize the fluctuation of energy consumption among nodes in a network. As a result, not only energy efficiency is achieved with the shortest chain length but also energy utilization is balanced for packet transmission. Ultimately, simulation results validate that the network lifetime of the EB-PEGASIS is about 2.46 times the original PEGASIS and 3.36 times the random projection-polar coordinate-chain (RPC) protocol for WSNs.