Compact dual-comb time-transfer and ranging for future space-based distributed sensing

Area of Science:

• Optical physics
• Metrology
• Instrumentation engineering

Background:

• Accurate time transfer and ranging are crucial for scientific applications.
• Existing systems often lack compactness and portability.
• Frequency comb technology offers unprecedented precision.

Purpose of the Study:

• To design and evaluate a compact frequency comb-based node for optical time transfer and ranging.
• To assess the performance of this node in a real-world free-space testbed.
• To demonstrate its potential for future high-precision measurement applications.

Main Methods:

• Developed a 14L, 10kg, 46W node integrating a frequency comb.
• Conducted ranging and time transfer experiments over a 4.4 km free-space link.
• Measured residual noise and system performance at low received power levels (20 nW).

Main Results:

• Achieved sub-femtosecond clock comparison precision.
• Demonstrated sub-micron range measurement accuracy.
• Confirmed system viability at 1-second averaging intervals.

Conclusions:

• The compact node design is suitable for high-precision optical time transfer and ranging.
• The system's performance supports future space-based distributed coherent sensing beyond 1 THz.
• This technology advances capabilities for global navigation and fundamental science.