Real-Time Particle Detection and Velocity Measurement by Means of Laser Doppler Velocimetry

In this paper, the authors describe a technique for laser Doppler anemometry (LDA) data processing using two Kalman filters in order to detect the presence of particles in the probe volume and to estimate their velocities. This method turns to be suitable for designing real-time integrated velocimeters. A first Kalman filter estimates the magnitude of the Doppler signal and then compares the estimated amplitude to a threshold. A second estimator uses an extended Kalman filter (EKF) to estimate particle velocity which is supposed to be a constant. Finally, this estimator is used in order to perform air velocity measurements in a pipe