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Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Optical periodic code matching by single-shot broadband frequency-domain cross-correlation.
1The Shirlee Jacobs Femtosecond Laser Research Laboratory, Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Haifa 32000, Israel. lev.chuntonov@weizmann.ac.il
Optics Express
|August 20, 2010
Summary
This study presents a novel optical method for matching periodic numerical sequences. The technique uses broadband cross-correlation measurements for reliable sequence identification, potentially aiding optical CDMA systems.
Area of Science:
- Optics and Photonics
- Information Technology
- Signal Processing
Background:
- Accurate matching of periodic numerical sequences is crucial for various applications, including optical communications.
- Existing methods may lack the speed and reliability required for high-performance systems.
- Optical techniques offer potential advantages in terms of speed and parallelism.
Purpose of the Study:
- To introduce and demonstrate a simple, reliable optical technique for matching periodic numerical sequences.
- To enable single-shot measurement of broadband cross-correlation functions in the frequency domain for sequence comparison.
- To explore the potential application of this technique in optical Code Division Multiple Access (CDMA) systems.
Main Methods:
- Optically encoding two periodic numerical sequences into the shapes of broadband femtosecond pulses using pulse-shaping.
- Mixing the shaped pulses with an additional amplitude-shaped narrowband pulse in a nonlinear medium.
- Measuring the spectrum of the resulting four-wave mixing (FWM) signal to obtain the cross-correlation function.
Main Results:
- Successfully demonstrated a single-shot optical measurement of the broadband cross-correlation function.
- Achieved high contrast between cross-correlation and auto-correlation functions, enabling reliable sequence matching.
- Identified sequence periods through the measured auto-correlation function for identical sequences.
Conclusions:
- The developed optical technique provides a simple and reliable method for matching periodic numerical sequences.
- The high contrast in correlation measurements ensures high reliability in determining sequence identity.
- This technique shows promise for practical implementation in optical CDMA communication protocols.
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