Notch filter for DC offset reduction in radio-frequency apparatus and associated methods

US7024221B2 · kind B2 · utility

Assignee

• Silicon Laboratories Inc. · US

Inventors

• Tod Paulus · New York, US
• Richard T. Behrens · Louisville, US
• Vishnu Srinivasan · Austin, US
• Mark S. Spurbeck · Superior, US
• Donald A. Kerth · Austin, US
• Jeffrey W. Scott · Austin, US
• G. Tyson Tuttle · Austin, US
• G. Diwakar Vishakhadatta · Austin, US

Key dates

• Filing date: Feb 12, 2002
• Grant date: Apr 4, 2006
• Expiry date: Jul 6, 2023

Classification

• Technology area (CPC H): Electricity
• CPC primary: H04B2215/064
• WIPO field: Telecommunications
• WIPO sector: Electrical engineering

Abstract

A radio-frequency (RF) receiver includes a receiver analog circuitry and a receiver digital circuitry coupled together. The receiver analog circuitry receives an RF signal. The receiver analog circuitry processes the received RF signal and generates a digital signal that it provides to the receiver digital circuitry. The receiver digital circuitry includes a digital down-converter circuitry that mixes the digital signal provided by a receiver analog circuitry with a digital intermediate frequency (IF) local oscillator signal to generate a digital down-converted signal. The receiver digital circuitry also includes a digital filter circuitry that filters the digital down-converted signal to generate a filtered digital signal. The digital filter circuitry provides a notch at a frequency that corresponds to a residual DC offset of the receiver analog circuitry.