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:
Jun. 21, 1994
Filed:
Mar. 29, 1993
Karl B Lindell, Lidingo, SE;
Ericsson GE Mobile Communications Inc., Research Triangle Park, NC (US);
Abstract
The invention relates to a method and to an arrangement for demodulating a signal (f) preferably frequency modulated with digital information, and then particularly a frequency shift modulated signal, with a frequency counter detector (16) which directly produces a digital value representative of the instantaneous frequency of the frequency modulated signal. In order to obtain the lowest possible uncertainty in frequency detection at unchanged counter frequencies (f.sub.r), the frequency modulated signal is mixed down to a difference frequency (f.sub.3) which is insignificantly higher than the sampling frequency (f.sub.s) required to extract the modulation information from the instantaneous counter value (N.sub.2) The frequency counter detector begins a counting sequence during each of the periods of the difference frequency.