Deterministic Modeling of Dynamic ISAC Channels in RF Digital Twin Environments

TL;DR

This paper presents a calibration methodology for RF Digital Twins to accurately simulate dynamic ISAC channels in complex urban environments, validated through measurements and ray tracing.

Contribution

It introduces a calibration approach combining ray tracing and channel sounding to align RF-DT simulations with real-world measurements for dynamic environments.

Findings

RF-DT accurately reproduces multipath evolution and Doppler signatures.

Calibration improves the realism of high-frequency ISAC simulations.

Method validated in urban scenarios with moving platforms.

Abstract

This paper introduces a methodology to calibrate Radio-Frequency Digital Twins (RF-DTs) for Integrated Sensing and Communication (ISAC) in dynamic wireless environments. The approach leverages high-resolution ray tracing in combination with wideband channel sounding to ensure consistency between simulated and measured propagation. The methodology is validated in urban scenarios featuring both mono-static and bi-static configurations, as well as moving user platforms and vehicles. Results show that the calibrated RF-DT reproduces key propagation effects, including multipath evolution, dynamic scatterers, and Doppler-induced signatures, with close agreement to measurements. These findings confirm that accurate geometry, material modeling, antenna patterns, and diffuse scattering are essential for realistic high-frequency ISAC simulation. By bridging the gap between simulation and measurement, the proposed calibration framework provides a scalable tool for developing and evaluating ISAC algorithms in complex, time-varying environments envisioned for 6G.