KEYNOTE: Ubiquitous Apertures at the AI-Driven Frontier of Phased-Array Systems for Integrated Sensing and Communications

This keynote bridges the gap between ISAC (integrated sensing and communications) concepts and fieldable engineering practice. We distill system-level design patterns and measurement-driven lessons from building and validating modern phased-array RF front-ends, spanning transceiver partitioning through radiated verification. The discussion is organized around three pillars: (i) scalable synchronization of clocks and local oscillators that enable coherent array growth without violating SWaP constraints; (ii) calibration architectures that remain stable across scan angle, wide instantaneous bandwidth, polarization, and temperature, explicitly accounting for embedded-element behavior; and (iii) over-the-air measurement workflows that connect radiated metrics, such as beam patterns, EVM where applicable, and ACPR/out-of-band emissions, back to actionable engineering decisions. A central theme is the responsible use of AI/ML, using physics-informed and measurement-constrained tools to close the loop on calibration stability and anomaly detection while remaining interpretable and testable. We conclude with open research problems that must be solved to scale verification, maintain performance across dynamic environments, and ensure ubiquitous apertures are reliable, verifiable, and trusted at scale.