Ph.D. Dissertation Proposal Defense: Minhao Cui, Exploiting Pervasive Leakage EM Signals for Communication, Charging, and Sensing

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Abstract

Wireless technologies are becoming increasingly important in our daily lives. As we use 4G and 5G services, researchers are also working on the development of future 6G networks. In addition to traditional communication functions like Wi-Fi, wireless signals are now being used for localization, sensing, and even charging. However, one significant challenge with these new applications is that they require dedicated signal transmissions, which can interfere with the original communication functions.

In my Ph.D. proposal, I aim to leverage the pervasive ambient leakage signals, which are typically seen as detrimental, to enhance wireless communication performance and enable new functions like sensing and charging. My approach is based on the observation that there is a significant amount of leakage RF signals in our environment. For instance, powerlines continuously emit 50/60 Hz electromagnetic (EM) signals due to the alternating current flowing through them. In my proposal, I will implement innovative designs in both hardware and software to transform these ambient leakages from adversaries into valuable assets.

We first explored that during the transmission of VLC, the transmitter not only emits out visible light signals but also leaks out RF signals due to  the intensity modulation scheme. What's more interesting is that the leakage RF signal contains a copy of the data transmitted in the light signals and this finding renders VLC—the generally believed most secure wireless technology—not secure any more. Building upon this finding, we further demonstrate a novel utilization of these leakage signals for carrying extra data to double the data rate of existing VLC systems. Following the successful utilization of VLC leakage signals for communication, we further view the leakage signals as a form of wasted energy and devote our effort to harvesting it with the help of wearable bracelet antenna. In this proposal, we are going to utilize the leakage signals for sensing purposes. This electromagnetic leakage, stemming from alternating current in the electric appliance, is governed by Maxwell's Equations. We can infer the body motions by analyzing such leakage signals received by the human body.

Therefore, we decide to leverage the EM leakage from electric vehicles (EVs) to enable in-vehicle sensing. We observe that numerous components within the EVs including battery, powerline, and power inverter, emit EM signals during their operation. And such leakage can be utilized to sense the body motions of the driver/passenger without any dedicated signal transmitters.

Advisor

Jie Xiong