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IEEE Photonics Technology Letters

Demonstration of Stealthy and Encrypted Optical Transmission Below Adjacent 50 GHz DWDM Channels

Eyal Wohlgemuth, Yaron Yoffe, Pantea Nadimi Goki, Muhammad Imran, Francesco Fresi, Luca Potì, Dan Sadot

Published Apr 7, 2020• 9 citations

Abstract

A stealthy and encrypted transmission is demonstrated in a dense-WDM network. The residual gap between two neighboring commercial channels is utilized for the transmission of the secured channel, hidden below the amplifier noise at negative -10 dB/0.1nm OSNR. The stealthy and encrypted channel is generated by a digital replication of the baseband signal together with a digital spectral phase mask. This technique provides encryption and steganography as it exclusively allows the eligible user to obtain a considerable processing-gain, and to recover extremely low OSNR signals. In this work the secured channel is explored under stringent network conditions. A stealth transmission was tested between two high OSNR public channels, separated 50 GHz apart: Unshaped 25 Gbps NRZ channel and digitally shaped coherent PM-QPSK 112 Gbps channel. Although it is significantly overlapped by adjacent channels and covered by the ASE noise, we demonstrate error-free detection of the secured channel, without significant effect on the commercial channels.

DOI: 10.1109/lpt.2020.2985670

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