Translator Disclaimer
12 January 2004 Doppler lidar prototype for speed measurements
Author Affiliations +
The classical radio technique used for FM detection, the frequency discriminator can also be used in optical frequency detection. In this sense, Chanin et al [2] proposed a lidar system that measures atmospheric wind fields by detecting Doppler-shift in the return signal in a differential way by using two Fabry-Perot interferometers or any other high resolution optical filters as frequency discriminators. This technique was also studied and used by Korb et al. They named it "edge-technique." The UPC lidar group is developing a wind lidar based on the "edge-technique." The first prototype of the wind lidar is a continuous-wave system that is able to measure the surface displacement velocity of solid targets. The transmitting laser is the seeder of a Spectra Physics GCR-190 laser, which will be used for the final wind measurements. It includes a Fairy-Perot interferometer, two APD-based optical receivers, and several auxiliary optics, electro-optic and electronic elements. Among them, there is a servo-loop, based on two acousto-optic frequency-shifters and a lock-in amplifier, which is responsible of the proper tuning between the laser and the Fabry-Perot interferometer. To our knowledge, this servo-loop has not been used before for wind lidars based on the edge-technique. The aim of this first prototype is to test the performance of the edge-technique to measure velocities and to assess the role of the servo-loop in the precision of the measurements. The study and design of the prototype, with emphasis in the servo-loop will be presented.
© (2004) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Constantino Munoz, Alejandro Rodríguez, Adolfo Comeron, Gilbert Bourdet, and Francesc Rocadenbosch "Doppler lidar prototype for speed measurements", Proc. SPIE 5240, Laser Radar Technology for Remote Sensing, (12 January 2004);


Back to Top