Patent · US Expired

Hybrid form digital filter

US5089981A · kind A · utility

11Cited by
13References
12Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 24, 1989
Grant dateFeb 18, 1992
Priority date
Expiry dateApr 24, 2009

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03H17/04
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A hybrid form digital filter. A digital filter is provided wherein the zeros of its transfer function are provided by a direct form digital filter portion and the poles of the transfer function are provided by a normal form digital filter portion. The hybrid filter provides truncation noise and stability characteristics like those of a normal form digital filter, but its filter coefficients may be calculated more rapidly than those for a normal form digital filter having the same transfer function, thereby enabling the coefficients to be calculated in real time for tuning the filter. While the preferred embodiment is a second order hybrid digital filter, the same principles are applicable to higher order digital filters as well.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.