... tractable narrow-band filter designs, using a 1D complex wavelet frame. This decomposition enables a single-pass adaptive subtraction via complex, single-sample (unary) Wiener filters, consistently estimated on overlapping windows in a complex wavelet transformed domain. Each unary filter compensates...

... local earthquakes will benefit from reduced noise levels and the ability to detect smaller events will be increased. We propose a frequency-dependent multichannel Wiener filtering technique with linear constraints that uses an adaptive least-squares method to remove coherent noise in seismic array data...

... excluded) if the noise were completely incoherent. However, actual stacking only improved SNR by 3–6 dB, caused by partially constructive noise interference. When the noise is coherent and distinct from the signal, we can do better. In this section, we apply the multichannel Wiener filter to three...

...Milton J. Porsani Abstract Two recursive algorithms for designing discrete Wiener filters for wavelets of different phase characteristics are the Simpson and the Manolakis recursions. Both procedures are efficient; however, both recursions work with a prefixed length filter. Two fast algorithms...

...Samuel H. Bickel; D. R. Martinez Abstract When Wiener filters are applied to seismic data, the bandwidth of noise increases along with the bandwidth of the signal. Thus the signal-to-noise ratio is degraded. To reduce signal ambiguity it is common practice to prewhiten the Wiener filter...

...P. J. Gunn Abstract It is possible to design multichannel Wiener filters to simultaneously process gravity and magnetic data in profile form so as to produce diagnostic rectangular wave outputs only if anomalies due to bodies with a specified density-magnetization ratio are input. This method has...

...R. J. Wang; S. Treitel Abstract The normal equations for the discrete Wiener filter are conventionally solved with Levinson's algorithm. The resultant solutions are exact except for numerical roundoff. In many instances, approximate rather than exact solutions satisfy seismologists' requirements...

... and the frequency content of individual signal and noise wavelets (events) on these traces. Therefore, a so-called “wavelet” Wiener filter is introduced which suppresses “noise” wavelets and enhances “signal” wavelets; this filter can be contrasted with an ordinary Wiener filter which discriminates between signal...

...H. J. Hwang; B. J. Mitchell Abstract A new technique which combines frequency-domain Wiener filtering and modal isolation is developed for determining interstation phase velocities, group velocities, and attenuation coefficients for seismic surface waves. Frequency-domain Wiener filtering is more...

...A. T. Walden Abstract Deconvolution in the presence of additive noise is a well known problem for which there exists a Wiener filter which spectrally whitens while also suppressing the noise. A simple variant of this standard Wiener filter incorporates a parameter p which is intended to allow...

... to the calculation of time-varying Wiener filters. The Berndt and Cooper technique produces an upper bound for the mean-square error between the true and a given approximated time-varying correlation function. The minimization of this upper bound leads to a relation which enables one to establish gate lengths...

...R. S. Pawlowski; R. O. Hansen Abstract We introduce a gravity anomaly separation method based on frequency-domain Wiener filtering. Gravity anomaly separation can be effected by such wavelength filtering when the gravity response from the geologic feature of interest (the signal) dominates one...

...Bo Holm Jacobsen Abstract Separation filtering is incomplete even under the ideal synthetic condition of known power spectra of the regional and residual fields. I have designed some Wiener filters, which minimize the inevitable separation error, from previous statistical source models of Naidu...

...J. Wang; J. Schweitzer; F. Tilmann; R. S. White; H. Soosalu Abstract Seismic arrays for detection of small earthquakes benefit from array processing aimed at reducing noise levels. We present a frequency-dependent multichannel Wiener filtering ( MCWF ) technique, which employs an adaptive least...

... the number of sub-filters N according to the formula 2 N - 1. The Wiener filter is an optimum filter in the least-squares sense but its errors occur across the output. The new filter is an optimum filter in an 'error-distribution' sense. Its errors are in reality the noncentral spikes of the spike sequence...

...Sven Treitel Abstract The ordinary time or space domain Wiener filter is conventionally obtained for real-valued inputs and real-valued desired outputs. Situations exist for which these variables are complex-valued.It is possible to develop a solution for the resulting complex Wiener filter...

... normal equations were also derived: ∑ m = 0 N f N ( m Δ t ) R x , x [ ( n − m ) Δ t ] = R x , y ( d ) ( n Δ t ) for n = 0, 1, …, N . In (1a), R x,x (t) is the autocorrelation function of a complex input signal x ( t ), f N ( t ) is the complex least-squares filter of duration ( N + 1)Δ t, y (d) ( t...