Information Theoretic Foundations of Joint Communication and Sensing

The integration of radio communication and sensing services in the same network infrastructure will be a key feature of next-generation wireless technology. It is envisaged that wireless base-stations will communicate with active devices, and simultaneously detect, localize and track passive targets within their vicinity; all using the same spectrum and hardware. This emerging joint communication and sensing (JCAS) paradigm, currently at the frontier of wireless research, will revolutionize a broad range of applications, from automotive and transportation to healthcare and environmental monitoring.A major challenge for realizing this vision is the lack of a fundamental theory for JCAS. Communication-centric wireless systems rely on information theory in establishing fundamental performance limits and guiding the design of efficient schemes that best utilize scarce radio resources. In sharp contrast, information theory for JCAS is currently in its infancy, and without such a theory, optimal signal and protocol design for next-generation wireless networks will remain elusive. The goal of this project is to take the first major steps towards closing this fundamental knowledge gap.I will first introduce a novel information-theoretic approach to sensing. I propose the new notions of sensing capacity and reliability function, which will enable characterizing the fundamental trade-off between sensing efficiency and reliability. I will then establish new information-theoretic performance limits and optimal schemes for JCAS systems, where signals have the dual function of communicating and probing. Finally, I will extend the analysis to multiple transceivers, targets and users, by introducing a novel network information theory for sensing and JCAS.The results of this project will open a new research frontier in information theory; push the boundaries of current knowledge in neighbouring domains; and directly impact the design of future, JCAS-enabled wireless technology.