Accession Number:

ADA244066

Title:

A Profiling Fiber-Optic Diode Laser Doppler Velocimeter for Deployment in Coastal Waters: Prototype Development. Phase 2

Descriptive Note:

Final rept. 28 Sep 89-30 Sep 91,

Corporate Author:

QUEST INTEGRATED INC KENT WA

Report Date:

1991-11-01

Pagination or Media Count:

71.0

Abstract:

A prototype profiling fiber-optic diode laser Doppler velocimeter FODLDV for flow measurement in coastal waters was developed, fabricated, and tested. The two-velocity-component FODLDV, a backscattered version of a field proven diode laser Doppler velocimeter DLDV, consists of a fiber-optic probe and link, an optronic module, a digital fast Fourier transform FFT based signal processor, and a data acquisition and control system DACS. The fiber- optic probe and link are mounted on a traverse that facilitates velocity profiling up to a maximum range of 3 m. The 1.6-cm diameter probe houses teh collimating lenses attached to three single-mode polarizing preserving fibers, the focusingreceiving lenses, and a multimode fiber. The four 12-m-long optic fibers, protected in a water-tight armor cable, serve as the optical link between the probe, and the module the single mode fibers transmit the frequency-shifted laser beams to the probe, and the multimode fiber transmits the backscattered light back to the photodetector. Command files allow all the operational parameters of the signal processor and the traverse to be modified on-the-fly. To operate the profiling FODLDV in an autonomous mode, a command file may be set up and executed to conduct an experimental sequence lasting for days, limited only by the capacity of the hard disk.

Subject Categories:

  • Test Facilities, Equipment and Methods
  • Fiber Optics and Integrated Optics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE