Filtering of Dispersed Wavetrains

Abstract

The filtering problem with dispersed signals is examined and an equation relating the duration of the filtered signal to the bandwidth of the filter and the dispersiveness of the dispersing system is established. This equation is applied in two domains: one, the optimization of the multiple filter technique, a method used for a time‐frequency analysis of a signal; and two, the choice of parameters in a ‘time variable filter’, a technique used to isolate from a signal a wavetrain related to a dispersion curve. We give an application of this ‘time variable filter’ technique to isolate the fundamental mode of Rayleigh waves from a record of an earthquake 650 km deep. Copyright © 1973, Wiley Blackwell. All rights reserved