Apparatus and method for demodulating a radio data system (RDS) signal

US6661292B2 · kind B2 · utility

Assignee

• Harman Becker Automotive Systems (Becker Division) GmbH · DE

Inventors

• Stefan Gierl · Karlsruhe, DE
• Christoph Benz · Ohlsbach, DE

Key dates

• Filing date: Mar 11, 2002
• Grant date: Dec 9, 2003
• Expiry date: Mar 11, 2022

Classification

• Technology area (CPC H): Electricity
• CPC primary: H04H2201/13
• WIPO field: Telecommunications
• WIPO sector: Electrical engineering

Abstract

To demodulate the RDS signal, the stereo-multiplex signal is multiplied in a first branch by the in-phase component of an oscillator filtered by a low-pass filter while decimated in its sampling rate and filtered by a high-pass filter while in a second branch it is multiplied by the quadrature component of the oscillator filtered by a low-pass filter decimated in its sampling rate, and filtered by a high-pass filter. An error signal to control the oscillator is calculated from the high-pass-filtered signals and the RDS bit clock. A clock generator generating the RDS bit clock is controlled by the first high-pass-filtered signal and by the oscillator. An RDS decoder, to whose input the first high-pass-filtered signal is applied. and an arithmetic unit which calculates the error signal from the high-pass-filtered signals and from the PDS bit clock are both clocked by the clock generator. The RDS data are retrievable from the output of the RDS decoder.