All-optical periodic code matching by a single-shot frequency-domain cross-correlation measurement

TL;DR

This paper demonstrates a single-shot optical method for measuring the cross-correlation of periodic sequences using frequency-domain techniques, enabling potential applications in optical CDMA communication.

Contribution

It introduces a novel all-optical, single-shot measurement technique for cross-correlation of periodic sequences using broadband phase-shaped pulses and four-wave mixing.

Findings

High contrast between cross-correlation and auto-correlation signals

Potential for optical implementation of CDMA protocols

Successful demonstration of frequency-domain cross-correlation measurement

Abstract

Optical single-short measurement of the cross-correlation function between periodic sequences is demonstrated. The sequences are encoded into the broadband ultrashort phase-shaped pulses which are mixed in the nonlinear medium with additional amplitude-shaped narrowband pulse. The spectrum of the resulted four wave mixing signal is measured to provide the cross-correlation function. The high contrast between the values of cross-correlation and auto-correlation (the latter includes also the information of the sequence period) has potential to be employed in the optical implementation of CDMA communication protocol.