Point-ahead demonstration of a transmitting antenna for satellite quantum communication

TL;DR

This paper presents a novel transmitting antenna with point-ahead capabilities for satellite quantum communication, achieving precise calibration and establishing a high-loss uplink to the Micius satellite, demonstrating its effectiveness for quantum links.

Contribution

The paper introduces a new antenna design with a point-ahead function and an accurate calibration method, enabling reliable satellite quantum communication links.

Findings

Achieved calibration accuracy better than 0.2 urad.

Established uplink to Micius satellite with 41-52 dB loss.

Validated the antenna's effectiveness for quantum communication.

Abstract

A low-divergence beam is an essential prerequisite for a high-efficiency longdistance optical link, particularly for satellite-based quantum communication. A point-ahead angle, caused by satellite motion, is always several times larger than the divergence angle of the signal beam. We design a novel transmitting antenna with a point-ahead function, and provide an easy-to-perform calibration method with an accuracy better than 0.2 urad. Subsequently, our antenna establishes an uplink to the quantum satellite, Micius, with a link loss of 41-52 dB over a distance of 500-1,400 km. The results clearly confirm the validity of our model, and provide the ability to conduct quantum communications. Our approach can be adopted in various free space optical communication systems between moving platforms.