Training a recursive filter by use of derivative function

USRE38374E1 · kind E1 · reissue

Inventor

• Ralph E. Rose · Bend, US

Key dates

• Filing date: Aug 26, 1999
• Grant date: Dec 30, 2003
• Expiry date: Aug 26, 2019

Classification

• Technology area (CPC —): General

Abstract

A method of training a recursive filter comprises updating recursive parameters of the filter with delta values computed from sampling of an error signal and obtaining derivative terms of the output signal with respect to the parameters. Adaptation using derivatives for FIR filters is known, but this technique was not available for IIR filters because of the unavailability of the derivative values. However, when it is realized that the derivative itself is recursive, a parameter derivative function is obtained which will produce derivative terms for updating the filter parameters with acceptable filter performance.