Optical periodic code matching by single-shot broadband frequency-domain cross-correlation.
We introduce and experimentally demonstrate a simple and reliable optical technique for matching between two periodic numerical sequences based on optical single-shot measurement of their broadband cross-correlation function in the frequency domain. Each sequence is optically encoded into the shape of the different broadband femtosecond pulse using pulse-shaping techniques. The two corresponding shaped pulses are mixed in a nonlinear medium together with an additional (amplitude-shaped) narrowband pulse. The spectrum of the resulting four-wave mixing signal is measured to provide the cross-correlation function of the two encoded sequences. For identical sequences it is the auto-correlation function that is being measured, allowing also the identification of the sequence period. The high contrast achieved here between cross-correlation and auto-correlation functions allows to determine with a very high reliability whether the two encoded sequences are identical or not. The demonstrated technique might be employed in an optical implementation of CDMA communication protocol.
Chuntonov
Lev
L
The Shirlee Jacobs Femtosecond Laser Research Laboratory, Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Haifa 32000, Israel. lev.chuntonov@weizmann.ac.il
Amitay
Zohar
Z
D003195:Computer Communication Networks / Q000295:instrumentation*; D001330:Electronic Data Processing / Q000379:methods*; D005336:Fiber Optic Technology / Q000295:instrumentation* / Q000379:methods*; D008962:Models, Theoretical; D017711:Nonlinear Dynamics; D013685:Telecommunications / Q000295:instrumentation*