A first-principles model of time-dependent variations in transmission through a fluctuating scattering environment

TL;DR

This paper develops a first-principles model for signal fading in complex environments using random matrix theory, explaining universal and specific effects, and validates it with microwave cavity experiments.

Contribution

It introduces a comprehensive RMT-based model for fading that unifies and extends traditional statistical models like Rayleigh and Rice fading.

Findings

Model agrees with Rayleigh/Rice in high-loss regimes

Deviations observed in low-loss systems where RMT fits better

Experimental validation with microwave cavities

Abstract

Fading is the time-dependent variation in transmitted signal strength through a complex medium, due to interference or temporally evolving multipath scattering. In this paper we use random matrix theory (RMT) to establish a first-principles model for fading, including both universal and non-universal effects. This model provides a more general understanding of the most common statistical models (Rayleigh fading and Rice fading) and provides a detailed physical basis for their parameters. We also report experimental tests on two ray-chaotic microwave cavities. The results show that our RMT model agrees with the Rayleigh/Rice models in the high loss regime, but there are strong deviations in low-loss systems where the RMT approach describes the data well.