Ray-Tracing Channel Modeling for LEO Satellite-to-Ground Communication Systems

TL;DR

This paper develops a ray-tracing based channel model for LEO satellite-to-ground links in urban scenarios, incorporating satellite orbit and Doppler effects, to improve understanding of signal characteristics for 6G systems.

Contribution

It introduces a novel LEO satellite-to-ground channel model using the SBR algorithm, accounting for satellite orbit perturbations and Doppler shifts, enhancing accuracy over previous models.

Findings

Received power peaks when satellite is near the receiver.

The model accurately predicts RMS delay spread and Doppler shift.

Ray-tracing effectively simulates urban LEO satellite channels.

Abstract

Based on the vision of global coverage for sixth-generation (6G) wireless communication systems, the low earth orbit (LEO) satellite-to-ground channel model for urban scenarios has emerged as highly important for the system design. In this paper, we propose an LEO satellite-to-ground channel model through shooting and bouncing rays (SBR) algorithm to analyze the channel characteristics. The orbit of LEO is modeled by the simplified general perturbations 4 (SGP4), and an accurate celestial model is applied to calculate the Doppler shift of multipath in a transmission time window of LEO satellite-to-ground communications. Channel characteristics of LEO satellite-to-ground communications such as the root-mean-square (RMS) delay spread, the Doppler shift, and the received power at different times are obtained. The simulation results show that the received power is only significantly noticeable in the transmission time window when the satellite is close to the receiver. Proposed model validates the effectiveness of ray-tracing in actual LEO satellite-to-ground communication scenarios and extends the calculation of the Doppler shift.