Method and filter arrangement for digital recursive filtering in the time domain

US7290022B2 · kind B2 · utility

Assignee

• Infineon Technologies AG · DE

Inventors

• Heinz Mattes · Munich, DE
• Peter Gregorius · Munich, DE
• Paul Lindt · Donauwörth, DE

Key dates

• Filing date: Nov 17, 2003
• Grant date: Oct 30, 2007
• Expiry date: Nov 29, 2025

Classification

• Technology area (CPC H): Electricity
• CPC primary: H03H17/04
• WIPO field: Basic communication processes
• WIPO sector: Electrical engineering

Abstract

A method and apparatus for fast digital filtering that requires only filter stages of first and second order. A desired rational filter transfer function is represented as a sum of first and second order intermediate transfer functions. A time dependent input signal is first fed in parallel into a plurality of first and second order intermediate recursive filter stages. Then, the outputs of the intermediate filter stages are summed up to an output filter signal that corresponds to the desired rational filter transfer function. The method and apparatus reduces the amount of calculational effort to the order of O(N), where N denotes the number of sampling points in the time domain, because the digital filtering is based on a discrete recursive convolution in the time domain.