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Updated: Jun 10, 2026
09:43
Transmission of Multiple Signals through an Optical Fiber Using Wavefront Shaping
Published on: March 20, 2017
Multi-rate synchronous optical undersampling of several bandwidth-limited signals
M Fleyer1, M Horowitz, A Feldtser
1Department of Electrical Engineering, Technion - Israel Institute of Technology, Haifa 32000, Israel. mikef@tx.technion.ac.il
Optics Express
|August 20, 2010
Summary
This study presents an optical system for undersampling unknown radio frequency signals up to 20 GHz. Synchronous sampling at multiple rates allows accurate signal reconstruction, even with overlapping frequencies.
Area of Science:
- Optical engineering
- Signal processing
- Radio frequency systems
Background:
- Undersampling is a technique to reduce sampling rates.
- Accurate reconstruction of signals with unknown carrier frequencies is challenging.
- Optical methods offer potential for high-speed signal processing.
Purpose of the Study:
- To demonstrate an optical system for undersampling multiple bandwidth-limited signals.
- To enable signal reconstruction with unknown and broad frequency ranges (0-20 GHz).
- To address challenges of signal overlap in the baseband.
Main Methods:
- Utilizing an optical system for signal undersampling.
- Employing synchronous sampling at three distinct rates.
- Down-converting the entire system bandwidth to a baseband region.
- Developing algorithms for accurate signal reconstruction.
Main Results:
- Experimental demonstration of the optical undersampling system.
- Successful reconstruction of three simultaneously generated chirped signals (200 MHz bandwidth each).
- Validation of the system's ability to handle overlapping signals in the baseband.
Conclusions:
- The proposed optical system effectively undersamples and reconstructs signals with unknown carrier frequencies.
- Synchronous multi-rate sampling is crucial for accurate reconstruction in overlapping scenarios.
- This technique has potential applications in radio frequency spectrum monitoring and analysis.
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