Fast linear optical sampling with high repetition-frequency using fiber delay lines.

Area of Science:

• Optical Engineering
• Signal Processing
• Laser Technology

Background:

• Linear optical sampling (LOS) is a key technique for optical modulation analyzers, typically using mode-locked fiber lasers (MFLs).
• Conventional LOS faces limitations with high-speed signals due to the MFL's restricted pulse repetition frequency, leading to measurement errors.

Purpose of the Study:

• To propose a novel dual-pulse mixing (DPM) based LOS system to overcome the repetition frequency limitations of conventional LOS.
• To enhance the measurement speed and range for high-speed signals.
• To improve the accuracy and reduce errors in optical modulation analysis.

Main Methods:

• Development of a DPM-based LOS system utilizing fiber delay lines to multiply optical pulses.
• Implementation of pulse location and peak extraction algorithms to compensate for time and amplitude biases.
• Experimental validation of the DPM-based LOS system's performance against conventional LOS.

Main Results:

• The DPM-based LOS system doubles the number of sampling points within the same time window compared to conventional LOS.
• A 9.1% reduction in error vector magnitude was achieved with the proposed DPM-based LOS system.
• Significant improvements in measurement speed and range were demonstrated.

Conclusions:

• The proposed DPM-based LOS system effectively increases sampling frequency and enhances measurement accuracy for high-speed signals.
• The developed pulse location and peak extraction algorithms successfully mitigate system biases.
• The DPM-based LOS technology shows substantial potential for advanced high-speed signal processing applications.