Open AccessStealth and secured optical coherent transmission using a gain switched frequency comb and multi-homodyne coherent detection
Author(s) -
Eyal Wohlgemuth,
Yaron Yoffe,
Pantea Nadimi Goki,
Muhammad Imran,
Francesco Fresi,
Prajwal D. Lakshmijayasimha,
Roi Cohen,
Prince M. Anandarajah,
L. Potì,
Dan Sadot
Publication year - 2021
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.431070
Subject(s) - optics , homodyne detection , computer science , transmission (telecommunications) , direct conversion receiver , physics , signal processing , phase noise , bandwidth (computing) , optical amplifier , electronic engineering , telecommunications , engineering , laser , radar
A novel all-optical stealth and secured transmission is proposed and demonstrated. Spectral replicas of the covert signal are carried by multiple tones of a gain switched optical frequency comb, optically coded with spectral phase mask, and concealed below EDFA's noise. The secured signal's spectrum is spread far beyond the bandwidth of a coherent receiver, thus forcing real time all-optical processing. An unauthorized user, who does not possess knowledge on the phase mask, can only obtain a noisy and distorted signal, that cannot be improved by post-processing. On the other hand, the authorized user decodes the signal using an inverse spectral phase mask and achieves a substantial optical processing gain via multi-homodyne coherent detection. A transmission of 20 Gbps under negative -7.5 dB OSNR is demonstrated here, yielding error-free detection by the eligible user.