Research on Reducing Doppler Signal Time-frequency Distributed Speckles
Wei Bo Yu · Journal of Kunming University of Science and Technology · 2003
Bigger noises and random fluctuations (forming Doppler speckles) are found in the Doppler signal spectra obtained from Short-time Fourier Transform (STFT) based on commercial Doppler analyzers. In order to reduce or inhibit these Doppler speckles, Wiener-Khintchine theorem is used to perform an auto correlation on the signal, reducing its electric noises and then conducting an Fourier Transform on the resulted signal with a Gaussian window function added to prevent the random fluctuations of spectrum. Finally better signal spectra are generated to reduce Doppler speckles.