Optical steganography hides stealth signal

April 1, 2009
Two low-latency chirped fiber Bragg gratings (CFBGs) were used by researchers at Princeton University (Princeton, NJ) to completely hide a “stealth” signal in an ordinary signal transmitted over a 1550 nm fiber-optic network.

Two low-latency chirped fiber Bragg gratings (CFBGs) were used by researchers at Princeton University (Princeton, NJ) to completely hide a “stealth” signal in an ordinary signal transmitted over a 1550 nm fiber-optic network. The technique relied on optical steganography, rather than optical encryption, to secure the signal (steganography hides a signal by obscuring it).

The public channel was a code-division multiple-access (CDMA) signal consisting of four wavelengths (1550.6, 1551.6, 1552.4, and 1553.4 nm); the stealth channel was created at 1551.5 nm–the same as one of the CDMA wavelengths–but at a power 10 dB lower than the public channel. Before combining the channels, the stealth channel was greatly dispersed by a compact 753 ps/nm CFBG, which spread it out and totally buried it in the public channel, hiding it in both the temporal and spectral domains. A second CFBG with equal but opposite dispersion to the first CFBG then reconstituted the stealth signal at the receiver. The technique induced a mere 1 dB power penalty in the successfully received public channel. For additional security in a real system, steganography could be combined with encryption. Contact Mable Fok at [email protected].

Sponsored Recommendations

Melles Griot® XPLAN™ CCG Lens Series

March 19, 2024
IDEX Health & Science sets a new standard with our Melles Griot® XPLAN™ CCG Lens Series fluorescence microscope imaging systems. Access superior-quality optics with off-the-shelf...

Spatial Biology

March 19, 2024
Spatial Biology refers to the field that integrates spatial information into biological research, allowing for the study of biological systems in their native spatial context....

Custom-Engineered Optical Solutions for Your Application

March 19, 2024
We combine advanced optical design and manufacturing technology, with decades of experience in critical applications, to take you from first designs to ongoing marketplace success...

Semrock Optical Filters Resources

March 19, 2024
Looking for more information about Semrock optical filters? Explore sets by fluorophore, download the 2023 Semrock catalog and more.

Voice your opinion!

To join the conversation, and become an exclusive member of Laser Focus World, create an account today!