The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 28, 1996
Filed:
May. 20, 1994
Wilhelm Hegeler, Hildesheim, DE;
Jurgen Kasser, Diekholzen, DE;
Detlev Nyenhuis, Sibbesse, DE;
Lothar Vogt, Hohenhameln, DE;
Blaupunkt-Werke GmbH, Hildesheim, DE;
Abstract
In a circuit for a demodulator of a radio data signal in a radio receiver, the multiplex signal in digital form is mixed into the baseband, in two phase positions shifted 90.degree. with respect to each other, after band-pass filtering, together with a reference carrier generated at a sampling clock rate produced in the radio receiver, thus producing a first and a second mix signal. A first and a second auxiliary signal with, respectively, a sine waveform and a cosine waveform are produced. The first mix signal is multiplied by the first auxiliary signal, and the second mix signal by the second auxiliary signal. The results of these multiplications are added together, producing a first output signal. The first mix signal is multiplied by the second auxiliary signal, and the second mix signal by the first auxiliary signal, and the results subtracted from each other, thus producing a second output signal. The phase position of the auxiliary signals is controlled in such a manner that the first output signal corresponds to the radio data signal (RDS) shifted down into the baseband.