Open AccessImproving the privacy of optical steganography with temporal phase masks
Author(s) -
Z. Wang,
Mable P. Fok,
Lei Xu,
John Chang,
Paul R. Prucnal
Publication year - 2010
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.18.006079
Subject(s) - transmission (telecommunications) , computer science , modulation (music) , optics , signal (programming language) , phase (matter) , compensation (psychology) , phase modulation , dispersion (optics) , synchronization (alternating current) , steganography , electronic engineering , channel (broadcasting) , physics , telecommunications , phase noise , acoustics , artificial intelligence , engineering , embedding , psychology , quantum mechanics , psychoanalysis , programming language
Temporal phase modulation of spread stealth signals is proposed and demonstrated to improve optical steganography transmission privacy. After phase modulation, the temporally spread stealth signal has a more complex spectral-phase-temporal relationship, such that the original temporal profile cannot be restored when only dispersion compensation is applied to the temporally spread stealth signals. Therefore, it increases the difficulty for the eavesdropper to detect and intercept the stealth channel that is hidden under a public transmission, even with a correct dispersion compensation device. The experimental results demonstrate the feasibility of this approach and display insignificant degradation in transmission performance, compared to the conventional stealth transmission without temporal phase modulation. The proposed system can also work without a clock transmission for signal synchronization. Our analysis and simulation results show that it is difficult for the adversary to detect the existence of the stealth transmission, or find the correct phase mask to recover the stealth signals.