Channel Modeling and Rate Analysis of Optical Inter-Satellite Link (OISL)

TL;DR

This paper develops a detailed channel model for optical inter-satellite links considering pointing errors, derives data rate estimates, and analyzes satellite cooperation to optimize network performance in non-terrestrial systems.

Contribution

It introduces a novel channel model for OISL considering jitter and noise, and provides a framework for optimizing satellite cooperation and laser frequency for improved data transmission.

Findings

The proposed model accurately predicts channel behavior under pointing errors.

Optimal satellite cooperation balances data rate and latency.

Simulation results validate the model and suggest ideal satellite configurations.

Abstract

Optical inter-satellite links (OISLs) improve connectivity between satellites in space. They offer advantages such as high-throughput data transfer and reduced size, weight, and power requirements compared to traditional radio frequency transmission. However, the channel model and communication performance for long-distance inter-satellite laser transmission still require in-depth study. In this paper, we first develop a channel model for OISL communication within non-terrestrial networks (NTN) by accounting for pointing errors caused by satellite jitter and tracking noise. We derive the distributions of the channel state arising from these pointing errors and calculate their average value. Additionally, we determine the average achievable data rate for OISL communication in NTN and design a cooperative OISL system, highlighting a trade-off between concentrating beam energy and balancing misalignment. We calculate the minimum number of satellites required in cooperative OISLs to achieve a targeted data transmission size while adhering to latency constraints. This involves exploring the balance between the increased data rate of each link and the cumulative latency across all links. Finally, simulation results validate the effectiveness of the proposed analytical model and provide insights into the optimal number of satellites needed for cooperative OISLs and the optimal laser frequency to use.