FFT-based cross-covariance processing of optical signals for speed and length measurement

Author

Claveau, Fabien ; Poirier, Michel ; Gingras, Denis

Author_Institution

Nat. Opt. Inst., Sainte-Foy, Que., Canada

Volume

5

fYear

1997

fDate

21-24 Apr 1997

Firstpage

4097

Abstract

The National Optics Institute has developed an optical velocimeter composed of two parallel laser beams for measuring perpendicularly the speed and the length of vehicles. The system must be capable of measuring speeds varying from 0 to 150 km/h in both directions with an accuracy of 1%. This paper focuses on the algorithms and signal processing aspects of the system. The speed is measured by estimating the time delay using an FFT-based cross-covariance method between the signals generated by the optical velocimeter. The length is estimated using the speed and the time window corresponding to the entire vehicle. The measurement algorithm has been implemented to run in real time on a C31 DSP and a 486 processor

Keywords

covariance analysis; delays; fast Fourier transforms; laser velocimetry; length measurement; optical information processing; road vehicles; velocity measurement; 0 to 150 km/h; FFT-based cross-covariance processing; National Optics Institute; algorithms; length measurement; optical signals; optical velocimeter; parallel laser beams; signal processing; speed; time delay estimation; vehicles; Delay effects; Delay estimation; Laser beams; Length measurement; Optical signal processing; Signal processing; Signal processing algorithms; Time measurement; Vehicles; Velocity measurement;

fLanguage

English

Publisher

ieee

Conference_Titel

Acoustics, Speech, and Signal Processing, 1997. ICASSP-97., 1997 IEEE International Conference on

Conference_Location

Munich

ISSN

1520-6149

Print_ISBN

0-8186-7919-0

Type

conf

DOI

10.1109/ICASSP.1997.604847

Filename

604847