Suppression of Cavity Time-Delay Signature Using Noise-Phase-Modulated Feedback

Hong Han,K Alan Shore,Zhi Wei Jia,Xu Min Cheng

doi:10.1109/access.2020.2975359

Hong Han, K Alan Shore + Show 2 more

Open Access

https://doi.org/10.1109/access.2020.2975359

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Journal: IEEE Access	Publication Date: Jan 1, 2020
Citations: 25	License type: CC BY 4.0

Affiliation: Taiyuan University of Technology, Bangor University

Abstract

We propose reconfiguration of the conventional feedback scheme to suppress the external-cavity time-delay signature (TDS) by adding noise phase modulation in the feedback of semiconductor laser. Noise-phase-modulated feedback introduces broad band noise frequencies into the feedback light and enables the suppression of the TDS. In this work, by means of simulations, the effect on TDS suppression of phase modulation (PM) index is explored. In addition, the influence of noise bandwidth variation is investigated. Using the auto-correlation function to quantity the TDS, we find that, for a large range of operating parameters, the TDS is significantly suppressed to the noise level and even submerged into the base noise. It is shown that suppression TDS is achievable over a wide operating parameter provided the noise generator bandwidth is of order 10 GHz and the PM index is greater than about 3. The proposed configuration will have widespread applications in contexts where suppression of the TDS is required.

Highlights

Optical chaos has many potential applications in chaos-based secure communication [1], chaos key distribution [2], Brillouin optical correlation domain analysis [3], physical random number generation [4], optical reflectometry [5], and chaos radar [6]
An external-cavity semiconductor laser is a common method to generate optical chaos, but this approach can induce a time-delay signature (TDS) corresponding to the length of the external-cavity. Such a TDS can be extracted from the auto-correlation function (ACF) of a chaotic time series and can be obtained from the RF spectrum of the chaos
It is found that as βPM increases, the TDS in ACF decreasing quickly, the TDS is suppressed to a relative small value

Summary

INTRODUCTION

Optical chaos has many potential applications in chaos-based secure communication [1], chaos key distribution [2], Brillouin optical correlation domain analysis [3], physical random number generation [4], optical reflectometry [5], and chaos radar [6]. An external-cavity semiconductor laser is a common method to generate optical chaos, but this approach can induce a time-delay signature (TDS) corresponding to the length of the external-cavity. In other applications of chaos such as, secure communication, key distribution, radar and random number generation, the presence of a TDS is not desirable. This is because the TDS induces periodic. He proposed a physical WDM transmission by using chaotic spectral phase encryption where the phase modulator was driven by chaos from a chaos optical injection and a mirror feedback [22].

THEORETICAL MODEL

SUPPRESSION RESULTS

CONCLUSION