Correlation and Temporal Consistency Analysis of Mono-static and Bi-static ISAC Channels

TL;DR

This paper investigates the relationship between mono-static and bi-static ISAC channels, revealing low instantaneous correlation but shared temporal evolution, which aids in designing robust 6G sensing and communication systems.

Contribution

It provides the first comprehensive empirical analysis of ISAC channel dynamics in urban environments, highlighting their correlation and temporal consistency characteristics.

Findings

Mono-static and bi-static channels have low instantaneous correlation.

Both channels exhibit shared temporal evolution.

Results validated across seven real-world scenarios.

Abstract

Integrated Sensing and Communication (ISAC) is critical for efficient spectrum and hardware utilization in future wireless networks like 6G. However, existing channel models lack comprehensive characterization of ISAC-specific dynamics, particularly the relationship between mono-static (co-located Tx/Rx) and bi-static (separated Tx/Rx) sensing configurations. Empirical measurements in dynamic urban microcell (UMi) environments using a 79-GHz FMCW channel sounder help bridge this gap. Two key findings are demonstrated: (1) mono-static and bi-static channels exhibit consistently low instantaneous correlation due to divergent propagation geometries; (2) despite low instantaneous correlation, both channels share unified temporal consistency, evolving predictably under environmental kinematics. These insights, validated across seven real-world scenarios with moving targets/transceivers, inform robust ISAC system design and future standardization.