Exploiting Interference for Secrecy Wireless Information and Power Transfer

RF signals enabled wireless information and power transfer (WIPT) is a cost-effective technique to achieve two-way communications and at the same time provide energy supplies for low-power wireless devices. However, the information transmission in WIPT is vulnerable to eavesdropping by energy receivers. To achieve secrecy communications with information nodes while satisfying the energy transfer requirement of energy receivers, an efficient solution is to exploit dual use of the energy signals also as useful interference or artificial noise to interfere with the energy receivers, thus preventing their potential information eavesdropping. Toward this end, this article provides an overview on the joint design of energy and information signals to achieve energy-efficient and secure WIPT under various practical setups, including simultaneous WIPT, wireless powered cooperative relaying and jamming, and wireless powered communication networks. We also present some research directions that are worth pursuing in the future.