Title :
Multistage digital prefiltering of noisy tachometer signals
Author :
Ovaska, Seppo J.
Author_Institution :
Kone Corp., Hyvinkaa, Finland
fDate :
9/1/1988 12:00:00 AM
Abstract :
A multistage digital prefiltering concept is discussed. The prefilter is implemented by using multirate signal-processing techniques, and contains both linear and nonlinear subfilters. The impulsive and wideband noise components are attenuated by a cascade of a standard median filter (SMF) and a low-order Hanning window (HW). A multirate digital filter is used to attenuate the 50/60-Hz power line frequency and its harmonics. The multirate principle with oversampling and decimation is used to reduce the complexity of the required analog antialiasing filter. The multistage filter was tested in a simulation environment and the results were satisfactory
Keywords :
digital filters; signal processing equipment; tachometers; 50 Hz; 60 Hz; analog antialiasing filter; harmonics; linear subfilters; low-order Hanning window; multirate digital filter; multirate signal-processing; multistage digital prefiltering; noisy tachometer signals; nonlinear subfilters; signal processing equipment; simulation; standard median filter; wideband noise; Distortion measurement; Electrons; Microprocessors; Nonlinear filters; Power harmonic filters; Power system harmonics; Rotation measurement; Semiconductor device noise; Velocity measurement; Wideband;
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on
