Abstract: Integrated Sensing and Communication (ISAC) is emerging as a defining pillar of 6G and beyond, dissolving the historical boundary between radar-style sensing and wireless data transfer into a single, spectrum- and hardware-efficient system. As networks push toward higher frequencies (mmWave and sub-terahertz), massive antenna arrays, and dense cell deployments, the same waveforms, apertures, and infrastructure used to communicate can simultaneously perceive the physical environment, localize users, track objects, image surroundings, and monitor the channel itself. This convergence promises to turn every base station and device into a dual-function node, enabling applications from autonomous mobility and unmanned aerial systems to smart factories, digital-twin environments, extended reality, and contactless health and security sensing. Realizing this vision, however, requires advances across the stack: joint waveform and beamforming design that balances the sensing–communication trade-off, scalable multi-antenna and reconfigurable-surface architectures, resource allocation under shared spectrum, and learning-based signal processing that exploits sensing to improve link reliability and vice versa. Equally critical are questions of security, privacy, and interference management as networks gain the ability to sense their users and surroundings. This work positions ISAC as both a technical opportunity and a research imperative, proposing a program to develop the theory, algorithms, and prototypes needed to establish sensing as a native, ubiquitous service of future communication networks.

Index Terms: 6G, Communications, Sensing.