Inter-satellite laser-ranging based on intradyne coherent detection.

Area of Science:

• Optics and Photonics
• Satellite Communications
• Metrology

Background:

• Laser communication networking necessitates advanced laser-ranging technologies.
• High-speed communication rates demand precise distance measurement capabilities.
• Existing ranging methods face challenges with clock phase and code loop errors.

Purpose of the Study:

• To achieve millimeter-level ranging accuracy in high-speed laser communication systems.
• To develop a robust method for continuous dynamic range measurement.
• To enable precise clock frequency deviation estimation between asynchronous terminals.

Main Methods:

• Implementation of intradyne coherent detection at 1048.576 Mbps.
• Combination of parallel clock phase difference calculation, frame head correlation, and ranging ambiguity region handling.
• Application of a ranging calibration method for corrected distance measurement.

Main Results:

• Millimeter-level corrected distance measurement achieved.
• Continuous dynamic range measurement above 1 m demonstrated.
• High-precision clock frequency deviation accurately derived for asynchronous terminals.

Conclusions:

• The proposed laser-ranging method enhances accuracy and reliability in high-speed communication.
• The technique is validated through on-orbit inter-satellite laser-ranging experiments.
• This advancement supports the development of sophisticated laser communication networks.