Battery-Aware Power Allocation for Lifetime Maximization of Wireless Sensor Networks

We consider a wireless sensor network deployed to observe a physical phenomenon. The sensors amplify and forward their observations to a remote fusion center via single hop. The objective is to maximize the operational lifetime of the network such that the estimate of the underlying source at FC satisfies a certain fidelity criterion given by the maximum tolerable estimation distortion. Each sensor is powered by a battery which limits its lifetime and consequently of the network also. Recent studies show that the battery discharge behavior is dependent on the load current: higher current leads to higher losses inside the battery due to the non-linearities of the electrochemical reaction in the battery. This work presents a power allocation design where goal is to maximize the network lifetime incorporating the non-linear discharging behavior of the batteries. The design is based on the knowledge of the instantaneous channel gains as well as when we only know the channel statistics. The numerical examples illustrate that the impact of battery-aware power scheduling on the network life is substantial.