Reducing Sensor Failure and Ensuring Scheduling Fairness for Online Charging in Heterogeneous Rechargeable Sensor Networks

The breakthrough of wireless power transfer technology provides an effective solution to the problem of energy depletion in Wireless Rechargeable Sensor Networks (WRSNs). Most existing work focuses on charging between a mobile charger and a requested sensor, such as NJNP and SAMER, under the assumption that sensors have the same battery capacity and energy consumption rate. In reality, it is more general that a WRSN consists of different types of sensors where they have different battery capacity and energy consumption rate, which is referred as Heterogeneous Wireless Rechargeable Sensor Network (HWRSN). We propose a novel online charging algorithm called VTMT to solve the charging problem in HWRSN. First, we propose the concept of Virtual Time, which is positively correlated with the waiting time of the requested sensor. Then selects the next charging sensor primarily based on the Virtual Time (VT) of the sensor and the Moving Time (MT) of the mobile charger to the node. Simulation results show that VTMT outperforms other charging schemes, which effectively reduce the failure rate of nodes and ensure the scheduling fairness.