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Quasi-light Storage for Optical Data Packets
Published on: February 6, 2014
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Note: Demodulation of spectral signal modulated by optical chopper with unstable modulation frequency
Shengzhao Zhang1, Gang Li1, Jiexi Wang2
1State Key Laboratory of Precision Measurement Technology and Instruments, Tianjin University, Tianjin 300072, China.
The Review of Scientific Instruments
|November 3, 2017
Summary
Frequency fluctuations from optical choppers distort amplitude calculations. We developed a method to estimate frequency variations and calculate amplitude using signal power within a selected range, reducing errors compared to conventional techniques.
Area of Science:
- Optical physics
- Signal processing
- Spectroscopy
Background:
- Optical choppers modulate light sources, but their rotating speed variations cause frequency jitter.
- Frequency fluctuations lead to distorted amplitude calculations in modulated signals.
- Accurate amplitude measurement is crucial for spectroscopic analysis.
Purpose of the Study:
- To develop a method for precisely calculating the amplitude of modulated light flux despite frequency fluctuations.
- To address the challenge of amplitude distortion caused by optical chopper speed variations.
Main Methods:
- Proposed a novel method to estimate the range of frequency fluctuations during spectral measurements.
- Extracted the signal amplitude based on the sum of power within a selected frequency range.
- Conducted experiments to validate the proposed method's feasibility.
Main Results:
- The proposed method demonstrated lower root mean square error compared to conventional amplitude calculation techniques.
- Experimental results confirmed the effectiveness of the amplitude extraction method in the presence of frequency jitter.
- The technique successfully compensated for amplitude distortions caused by modulation frequency variations.
Conclusions:
- The developed method provides a more accurate way to calculate modulated light flux amplitude.
- This approach is valuable for spectroscopic measurements affected by optical chopper instability.
- The findings offer an improved solution for precise signal amplitude determination in modulated optical systems.
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