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Time and frequency -Domain Interpretation of Phase-lag Control01:21

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Related Experiment Video

Updated: May 28, 2026

Transmission of Multiple Signals through an Optical Fiber Using Wavefront Shaping
09:43

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Published on: March 20, 2017

Spectral and temporal stealthy fiber-optic communication using sampling and phase encoding.

Tomer Yeminy1, Dan Sadot, Zeev Zalevsky

  • 1Department of Electro-Optical Engineering, Ben Gurion University, Beer Sheva, 84105 Israel. tomeryem@bgu.ac.il

Optics Express
|October 15, 2011
PubMed
Summary
This summary is machine-generated.

This study introduces a novel method for covert fiber-optic communication, achieving stealthy transmission in both time and frequency domains by spreading signals below noise levels.

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Area of Science:

  • Optical Communications
  • Signal Processing
  • Cryptography

Background:

  • Covert communication is crucial for secure data transmission.
  • Existing methods often require dedicated bandwidth or complex infrastructure.
  • Stealthy signal transmission in fiber optics presents significant challenges.

Purpose of the Study:

  • To develop a novel method for covert fiber-optic communication.
  • To achieve signal concealment in both frequency and time domains.
  • To enhance data security in optical networks.

Main Methods:

  • Utilizing sampling to spread the power spectral density of the information-bearing pulse sequence below the noise level.
  • Employing temporal phase encryption to prevent coherent addition of pulses in the frequency domain.
  • Implementing spectral phase encoding for temporal spreading of the pulse sequence.

Main Results:

  • Successfully reduced the signal power spectral density below the noise floor.
  • Achieved spectrally concealed signal transmission without occupying public user bandwidth.
  • Demonstrated stealthy temporal and spectral transmission characteristics.

Conclusions:

  • The proposed method offers a viable solution for covert fiber-optic communication.
  • The technique effectively conceals signals in both time and frequency domains.
  • This approach enhances the security of optical communication systems.