An Energy-Aware Cluster Head Selection and Relay Strategy for Efficient Data Transmission in Smart City WSNs

One of the fundamental challenges in wireless sensor networks (WSNs) is ensuring reliable data transmission while optimizing energy efficiency. This paper addresses this challenge by proposing a novel multi-criteria cluster head (CH) selection algorithm and an adaptive relay strategy for energy-harvesting WSNs in smart city environments. Our approach integrates four key metrics for CH selection: proximity to the sink, residual energy, transmission reliability, and power consumption. Additionally, we introduce a dynamic multi-hop routing protocol to mitigate obstacles and enhance network reliability. The proposed work is formulated as a non-convex optimization problem and transformed into a convex problem for efficient solution. Simulation results demonstrate significant improvements compared to previous works: energy efficiency increases by up to 45% over entire rounds, the network transmission ratio improves packet delivery rates by 30-40%, and outage probability is reduced to near-zero levels under stable network conditions. These metrics are evaluated under varying modified subsistence ratios (0.15 and 0.45), highlighting the robustness of our method. These improvements originate from multi-criteria cluster head selection, obstacle-aware routing, and energy management, collectively extending network lifetime and reliability for large-scale smart city deployments.