1 September 2002 Short-range remote spectral sensor using mid-infrared semiconductor lasers with orthogonal code-division multiplexing approach
Author Affiliations +
Optical Engineering, 41(9), (2002). doi:10.1117/1.1497614
Abstract
Demonstration of short-range multispectral remote sensing, using 3 to 4-?m mid-infrared Sb semiconductor lasers based on codedivision multiplexing (CDM) architecture, is described. The system is built on a principle similar to intensity-modulated/direct-detection optical- CDMA for communications, but adapted for sensing with synchronous, orthogonal codes to distinguish different wavelength channels with zero interchannel correlation. The concept is scalable for any number of channels, and experiments with a two-wavelength system are conducted. The CDM-signal processing yielded a white-Gaussian-like system noise that is found to be near the theoretical level limited by the detector fundamental intrinsic noise. With sub-mW transmitter average power, the system was able to detect an open-air acetylene gas leak of 10-2 STPft3/hr from 10-m away with time-varying, random, noncooperative backscat- ters. A similar experiment detected and positively distinguished hydrocarbon oil contaminants on water from bio-organic oils and detergents. Projection for more advanced systems suggests a multi-kilometer-range capability for watt-level transmitters, and hundreds of wavelength channels can also be accommodated for active hyperspectral remote sensing application.
Zulfikar Morbi, D. B. Ho, H.-W. Ren, Han Q. Le, Shin Shem Pei, "Short-range remote spectral sensor using mid-infrared semiconductor lasers with orthogonal code-division multiplexing approach," Optical Engineering 41(9), (1 September 2002). http://dx.doi.org/10.1117/1.1497614
JOURNAL ARTICLE
17 PAGES


SHARE
KEYWORDS
Signal to noise ratio

Transmitters

Sensors

Receivers

Remote sensing

Interference (communication)

Semiconductor lasers

RELATED CONTENT

Compact XeCl-laser with output energy of 120 J
Proceedings of SPIE (May 31 2006)
Using phase correlation approach to correct images
Proceedings of SPIE (September 01 1995)
Laser viability method for red blood cells state monitoring
Proceedings of SPIE (January 15 1996)
Advances in frame transfer devices
Proceedings of SPIE (August 12 1992)

Back to Top