A Novel Multi-Objective Optimization-Based Path Formulation for Mobile Sink in Wireless Sensor Networks

Abstract

As a consequence of the limited battery life of sensor nodes ( $\mathbb{S}\mathbb{N}$s) in wireless sensor networks ($\mathbb {WSN}$s), the $\mathbb{S}\mathbb{N}$s nearby the sink exhaust rapidly and exhibit the hot spot problem. The mobile sink ($\mathbb{M}\mathbb{S}$) is proposed to be the solution as it helps in decreasing the energy consumption of $\mathbb{S}\mathbb{N}$s. This further results in an increased network lifetime. Moreover, some sensor applications require a precise data collection time and hence need to optimize the path length of the $\mathbb{M}\mathbb{S}$. This ensures that $\mathbb{M}\mathbb{S}$ will collect data from all the $\mathbb{S}\mathbb{N}$s in a certain threshold time. In the proposed approach, we use the concept of the Voronoi diagram and consider their vertices as the probable set of rendezvous points ($\mathbb{R}\mathbb{P}$s) for the mobile sink to collect data from $\mathbb{S}\mathbb{N}$s. These rendezvous points are further optimized using a cost function which is generated by using several parameters that affect the performance of each rendezvous point. The final set of rendezvous points resulting in the longest path within permissible delay is then finalized. The proposed method is simulated and compared with the existing approaches. The comparison is performed under different parameters like network lifetime, number of hop count, number of alive $\mathbb{S}\mathbb{N}$s, and so on.