Battery-Friendly Packet Transmission Algorithms for Wireless Sensor Networks

The core problem with nodes of wireless sensor networks is the limited charge capacity for the power-operated battery. The main concern of this paper is how to extend the battery's lifetime. According to the characteristics and functionality of sensor nodes, the sensor applications are categorized into three distinct types, i.e., the hard real-time applications, the soft real-time applications, and the periodic applications. For the hard real-time applications, a battery-friendly lazy packet scheme is designed to draw smoother and lower current for minimizing battery charge consumption. A battery-friendly local optimization scheme with slack time is exploited and evaluated for the soft real-time applications. For the periodic applications, a battery-aware task–scheduling algorithm is developed, which reschedules tasks of sensor nodes to achieve the battery friendly discharge profile. The simulation results show that the three battery-friendly algorithms perform better in extending lifetime of battery-operated sensor nodes and minimizing battery charge consumption.