Propagation Channel Modeling for LEO Satellite Missions Using Ray-Tracing Simulations

TL;DR

This paper develops a comprehensive, high-resolution ray-tracing-based channel model for LEO satellite-to-ground links at X-band, incorporating environmental dynamics, elevation effects, and antenna misalignment, validated through simulations.

Contribution

It introduces the first elevation-aware, environment-integrated channel model for LEO satellite links at X-band, including phased-array antenna effects.

Findings

Quantifies large-scale fading due to terrain and weather.

Models small-scale fading with Rician distribution.

Assesses impact of antenna misalignment on link quality.

Abstract

This work presents a high-resolution, ray-tracing-based channel modeling for Low Earth Orbit (LEO) satellite-to-ground links in a suburban environment at X-band. Using simulations conducted in Wireless InSite, we develop a parametric channel model that characterizes both large- and small-scale fading effects across different satellite elevation angles. Large-scale fading incorporates attenuation due to terrain-induced shadowing and dynamic environmental factors such as weather conditions, and is compared with 3GPP NTN channel model. Additionally, we quantify link degradation resulting from ground station (GS) antenna misalignment, considering both fixed single-element and electronically steerable phased-array antennas. Small-scale fading is modeled by fitting a shadowed and non-shadowed Rician distribution to the fading statistics at various satellite elevations. To the best of our knowledge, this is the first study to propose a comprehensive elevation-aware channel model for satellite-to-ground propagation at X-band, integrating ray-traced environmental dynamics, elevation-dependent fading, and phased-array beam misalignment effects.