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:
Apr. 22, 1986
Filed:
Jan. 14, 1985
Norbert Eilers, Hildesheim, DE;
Peter Bragas, Itzum, DE;
Blaupunkt-Werke GmbH, Hildesheim, DE;
Abstract
FM transmission system in which, besides program content, an auxiliary carrier of, for example 57 kHz, is radiated, which auxiliary carrier is modulated by an announcement recognition (AR) signal and by a region or radio-station recognition (RR) signal, the AR and RR signals being low-frequency, AM modulations on the auxiliary carrier. To enhance recognition of an AR signal, e.g. between 142 and 170 Hz, is enhanced, in spite of reception difficulties, for example due to multi-path reception and the like, by decreasing the modulation of the 57 kHz subcarrier by the RR signal to 30% or less, while the AR signal is modulating the subcarrier, so that the AR modulation may extend to 60 and even 90% modulation. Multiple AR frequencies can be used, for example to characterize different announcements, e.g. in different languages, or of different characteristics, such as traffic, news, sports, or others, recognition of the AR signal in the receiver permitting switch-over from other reproduced programs, e.g. tape, to the demodulator from the receiver tuned to the station emitting the AR signal, to reproduce the announcement, or the like.