Nonlinear Wigner Ville spectrum estimation using wavelet soft thresholding
نویسنده
چکیده
The large variance of the Wigner Ville distribution makes smoothing essential for producing readable estimates of the time varying power spectrum of noise corrupted signals Since linear smoothing trades reduced variance for increased bias of the signal components we explore two nonlinear estimation techniques based on soft thresholding in an orthonormal basis representation Soft thresholding provides considerable variance reduction without greatly impairing the time frequency resolution of the estimated spectrum
منابع مشابه
Wigner-ville Spectrum Estimation via Wavelet Soft-thresholding
The high noise sensitivity of the Wigner distribution makes smoothing a necessity for producing readable time-frequency images of noise corrupted signals. Since linear smoothing suppresses noise at the expense of considerable smearing of the signal components, we explore two nonlinear denoising techniques based on soft-thresholding in an orthonormal basis representation. Soft-thresholding provi...
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