Photonic instantaneous microwave frequency measurement based on frequency-phase mapping with high precision

Area of Science:

• Photonics and Optical Engineering
• Microwave Engineering
• Signal Processing

Background:

• Accurate and instantaneous microwave frequency measurement is crucial for various applications.
• Existing methods often face limitations in range, accuracy, or system complexity.
• The need for stable and compact measurement systems persists.

Purpose of the Study:

• To propose and validate a novel instantaneous microwave frequency measurement scheme.
• To leverage a frequency-phase mapping technique for enhanced accuracy.
• To develop a compact and stable system for microwave frequency measurement.

Main Methods:

• Modulating a low-frequency (LF) reference signal and two delayed microwave signals onto optical carriers using dual-parallel Mach-Zehnder modulators.
• Generating an electrical signal whose phase shift is dependent on microwave frequency and time delay.
• Constructing a linear frequency-phase mapping function for accurate measurement.

Main Results:

• Achieved instantaneous microwave frequency measurement.
• Demonstrated a linear frequency-phase mapping with a high slope for improved accuracy.
• Simulated a measurement range of 4.1-40 GHz with errors below ±0.04 GHz.
• Developed a compact system design lacking optical filters and polarization devices for enhanced stability.

Conclusions:

• The proposed frequency-phase mapping technique enables accurate and instantaneous microwave frequency measurement.
• The compact, filter-free design enhances system stability and simplifies implementation.
• The scheme offers a promising solution for high-accuracy, wide-range microwave frequency monitoring.