Abstract:  Wireless Sensor Networks (WSNs), when integrated with the Internet of Things (IoT), have emerged as a rapidly advancing field due to their cost-effectiveness, ease of deployment, and low maintenance requirements. In WSN sensor nodes are deployed in huge amount for sensing the information from target. Every sensor node is battery powered and basic requirement is to use this battery power in an efficient way. This will increase number of alive nodes and ultimately prolongs a network lifetime. In this research, we present a novel energy-aware cluster head (CH) selection and multihop routing protocol for Wireless Sensor Networks (WSNs) using Particle Swarm Optimization (PSO). Unlike previous methods that focus solely on distance or residual energy, our approach integrates both parameters into a composite fitness function. Additionally, we introduce a dynamic multihop routing mechanism that intelligently selects relay nodes based on energy thresholds with sleep scheduling. Comparative simulations show that our method prolongs network lifetime, improves energy efficiency, reduces latency, and outperforms existing methods such as standard PSO, fuzzy-PSO, and hybrid PSO-GWO techniques.

Keywords: Wireless Sensor Networks, Particle Swarm Optimization, Energy Efficiency, Multihop Routing, Cluster Head Selection, Energy-Aware Protocol