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High-accuracy fourier transform interferometry, without oversampling, with a 1-bit analog-to-digital converter
1National Institutes of Physics, University of the Philippines, Diliman, Quezon City 1101, The Philippines.
Applied Optics
|March 14, 2008
Summary
We present a novel 1-bit analog-to-digital (AD) converter technique for accurate Fourier transform interferometry without oversampling. This method enables precise spectral analysis of light sources, achieving high performance with simple hardware.
Area of Science:
- Optical Physics
- Metrology
- Signal Processing
Background:
- Fourier transform interferometry is crucial for spectral analysis.
- Existing 1-bit analog-to-digital (AD) converter schemes often require oversampling, increasing complexity.
- Accurate spectral recovery from limited-bit data remains a challenge.
Purpose of the Study:
- To introduce a new technique for accurate Fourier transform interferometry using a 1-bit AD converter.
- To demonstrate a method that circumvents the need for oversampling.
- To enable high-resolution spectral analysis with simplified hardware.
Main Methods:
- Utilized sinusoid-crossing sampling to locate interferogram modulation term intersections with a reference sinusoid.
- Developed a novel autocorrelation-based procedure for recovering equally sampled amplitude data from crossing points.
- Applied the technique to determine the spectrum of an argon-ion laser.
Main Results:
- Achieved accurate Fourier transform interferometry with a 1-bit AD converter without oversampling.
- The developed method recovers the spectrum even in the presence of additive noise.
- Demonstrated performance equivalent to a 13-bit amplitude-sampling AD converter.
Conclusions:
- The proposed 1-bit AD converter technique offers a simplified and accurate approach to Fourier transform interferometry.
- Sinusoid-crossing sampling combined with autocorrelation-based recovery meets Nyquist criteria for spectral analysis.
- This method provides a cost-effective solution for high-resolution spectral measurements.
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