A Multi-Armed Bandit Approach to Wireless Information and Power Transfer

Multiple wireless transmitters communicate with their information receivers while radiating RF energy to multiple nearby energy harvesters. The channels from the transmitters to the receivers and to the energy harvesters are time-varying and unknown. The transmitters jointly determine their multi-antenna transmissions to fairly charge all the energy harvesters while maintaining the signal-to-interference-and-noise ratio at the receivers. In this letter, this task is formulated as a combinatorial multi-armed bandit problem and is solved with the upper confidence bound algorithm. Numerical results show that the algorithm can quickly converge to the optimal strategy with moderate signaling overhead. It has superior performance in fair energy harvesting while maintaining communication quality.