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:
Feb. 25, 2003
Filed:
Aug. 10, 2001
Jean Ravatin, Moirans, FR;
Michel Ayraud, Voreppe, FR;
Atmel Grenoble S.A., Saint-Egreve, FR;
Abstract
In digital signal demodulation and detection circuits, especially digital radio signal reception and processing circuits, the signals are received in analog form and have to be converted into logic levels. This is done in practice by comparing the level of the signal with its mean level. The mean level is established by an RC lowpass filter which introduces an inconvenient delay into the preparation of the mean level. The mean level of the signal, established by an RC filter is compared and applied to an input B of a comparator COMP, at the level of the analog signal delayed by a phase-shifter and applied to another input A of the comparator. In order that the delay introduced by the phase-shifter into the analog signal may be substantially the same as the delay given to the mean value by the RC circuit, the phase-shifter is made with the same RC circuit and an amplifier mounted so as to set up a phase shift transfer function of the (1−RCp)/(1+RCp) type where p is the Laplace variable.