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:
Mar. 31, 2015
Filed:
Jul. 20, 2012
Michael Virnich, Korlingen, DE;
David Hoyer, Ayl, DE;
Martin Thinnes, Trierweiler, DE;
Michael Puetz, Trier, DE;
Thomas Meyers, Bitburg, DE;
Michael Virnich, Korlingen, DE;
David Hoyer, Ayl, DE;
Martin Thinnes, Trierweiler, DE;
Michael Puetz, Trier, DE;
Thomas Meyers, Bitburg, DE;
IEE International Electronics & Engineering S.A., Luxembourg, LU;
Abstract
A plural-frequency capacitive occupancy sensing system comprises an antenna electrode and a detection circuit, which is configured to drive the antenna electrode at least with a first and a second signal at a first and a second frequency, respectively, so as to obtain at least a first and a second measurement value indicative of at least one of conductance, susceptance, resistance, reactance and capacitance between the antenna electrode and a reference node, at the first frequency and the second frequency, respectively. The detection circuit compares the capacitance between the antenna electrode and the reference node with a threshold capacitance, the threshold capacitance being derived from a difference between the first and second measurement values and/or the capacitance between the antenna electrode and the reference node being corrected based upon the difference between the measurement values. The detection circuit outputs an occupancy state signal depending on the comparison.