A low energy consumption routing protocol for mobile sensor networks with a path-constrained mobile sink

Installing a mobile sink on the public vehicle, which is a path-constrained vehicle, to collect data in a mobile sensor network can lower maintenance cost. However, immediately sending the data packet to the mobile sink when it arrives does not guarantee the shortest path, leading to high energy consumption. Meanwhile, immediately sending the data packet to the closest future position of the mobile sink can guarantee the shortest path. However, the mobile sensor node, which buffers the data packet while waiting for the mobile sink to arrive, may move away from the trajectory, resulting in reduction of delivery ratio. Therefore, we shall propose to delay sending the data packet until the mobile sink approaches the position with the shortest path. It not only guarantees the shortest path but also exhibits robustness with dynamic node mobility. Via extensive simulations, we show that our proposed scheme can effectively reduce energy consumption and increase delivery ratio even for the high-speed mobile sink.