(WSNs) are being increasingly used in a wide variety of applications
including industrial and infrastructure monitoring, smart home,
smart grid, medical systems, and so on.
One of the main challenges and performance bottleneck in these systems is the
limited lifetime of the sensor nodes due to their energy supply.
Recent advances in the area of wireless energy transfer allow
sensors to recharge during network operation, thereby extending
their lifetimes and minimizing application downtime.