An Error Analysis of Digital Equalizing Filters
John F. Hemdal · Seismological Research Letters · 1967
Research Article| September 01, 1967 An Error Analysis of Digital Equalizing Filters John F. Hemdal John F. Hemdal Geophysics Laboratory, Institute of Science and Technology, University of Michigan, Ann Arbor, Michigan Search for other works by this author on: GSW Google Scholar Author and Article Information John F. Hemdal Geophysics Laboratory, Institute of Science and Technology, University of Michigan, Ann Arbor, Michigan Publisher: Seismological Society of America First Online: 09 Mar 2017 Online ISSN: 1938-2057 Print ISSN: 0895-0695 © 1967 by the Seismological Society of America Seismological Research Letters (1967) 38 (3-4): 11–33. https://doi.org/10.1785/gssrl.38.3-4.11 Article history First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation John F. Hemdal; An Error Analysis of Digital Equalizing Filters. Seismological Research Letters 1967;; 38 (3-4): 11–33. doi: https://doi.org/10.1785/gssrl.38.3-4.11 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietySeismological Research Letters Search Advanced Search Abstract Present day computer systems allow computation of an approximate Wiener operator for the time-domain filtering and smoothing of signals of finite (and short) length. However, the memory capacity of a particular computer storage introduces a constraint on the length of the operator and signal. To produce the least mean-square-error, it was helpful to know the extent to which the length of the operator whould be compromised by including additional information (sample points) of the signal. If N is the number of samples of the signal to be equalized and T is the number of points in the optimum digital operator, then the system imposes the constraint that KN+f(T)<Mwhere M is the free capacity of the computer memory and K is the number of multiples of signal length required for the correlations.To find out whether an optimum relation between T and N exists, a program to determine the digital operator and to compute the mean-square-error between the filtered result and the desired signal was written for an IBM 7090 computer. The computed errors for some typical seismic signals are presented as a function of operator length, signal length, signal-to-noise ratio, and the number of records used to determine averages. The results suggest that equalization occurs both as a process of signal shaping and of noise-reduction, but not necessarily simultaneously. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.