An Unequal Clustering and EPPR-Initialized Ant Colony Multihop Routing Protocol for Wireless Sensor Networks

Wireless sensor network operation is constrained by uneven cluster loads, intercluster communication costs, and maintenance that does not reflect node condition. UEAD combines distance-adaptive unequal clustering, EPPR-initialized ant colony optimization (ACO), and health-driven maintenance. Smaller clusters near the base station limit member-data reception loads, while larger distant clusters reduce the number of remote source heads. The base-station-personalized EPPR prior uses radio-link communication costs to initialize ACO pheromones, and cluster health determines local head rotation or global reclustering. MATLAB R2025b simulations evaluate route quality, network lifetime, and control and computational overhead. At five iterations, the complete EPPR–ACO implementation reduced mean route energy from 2.348 to 1.940 mJ; ACO was slightly lower at 20–100 iterations. Equal-total-time tests, including EPPR preprocessing, showed an EPPR–ACO advantage at short budgets and similar energy at longer budgets. In the lifetime comparisons, UEAD delayed node loss and retained more residual energy than Standard LEACH and DUCISCA. Fixed-area, 50-round tests with 200–1000 nodes showed lower modeled control energy for UEAD under the stated accounting models, but substantially higher runtime at 1000 nodes.