کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
732088 1461619 2016 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Influence of speckle effect on doppler velocity measurement
ترجمه فارسی عنوان
تأثیر اثر اسپکتیو بر اندازه گیری سرعت داپلر
موضوعات مرتبط
مهندسی و علوم پایه سایر رشته های مهندسی مهندسی برق و الکترونیک
چکیده انگلیسی


• Theoretical model of speckle effect on the spectrum of Doppler signal is built.
• A coherent Lidar system is established for experiments.
• Spot size of laser beam on target affects the velocity measurement accuracy.
• Large transverse velocity of target will broaden the spectrum of Doppler signal.
• Surface roughness of target has influence on Doppler signal.

In a coherent Lidar system, velocity measurement of a target is achieved by measuring Doppler frequency shift between the echo and local oscillator (LO) signals. The measurement accuracy is proportional to the spectrum width of Doppler signal. Actually, the speckle effect caused by the scattering of laser from a target will broaden the Doppler signal's spectrum and bring uncertainty to the velocity measurement. In this paper, a theoretical model is proposed to predict the broadening of Doppler spectrum with respect to different target's surface and motion parameters. The velocity measurement uncertainty caused by the broadening of spectrum is analyzed. Based on the analysis, we design a coherent Lidar system to measure the velocity of the targets with different surface roughness and transverse velocities. The experimental results are in good agreement with theoretical analysis. It is found that the target's surface roughness and transverse velocity can significantly affect the spectrum width of Doppler signal. With the increase of surface roughness and transverse velocity, the measurement accuracy becomes worse. However, the influence of surface roughness becomes weaker when the spot size of laser beam on the target is smaller.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Optics & Laser Technology - Volume 80, June 2016, Pages 22–27
نویسندگان
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