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:
Dec. 24, 2013
Filed:
Dec. 18, 2009
Guozhong Gao, Watertown, MA (US);
H. Frank Morrison, Berkeley, CA (US);
Hong Zhang, El Sobrante, CA (US);
Richard A. Rosthal, Richmond, CA (US);
David Alumbaugh, Berkeley, CA (US);
Cyrille Levesque, La Defense, FR;
Guozhong Gao, Watertown, MA (US);
H. Frank Morrison, Berkeley, CA (US);
Hong Zhang, El Sobrante, CA (US);
Richard A. Rosthal, Richmond, CA (US);
David Alumbaugh, Berkeley, CA (US);
Cyrille Levesque, La Defense, FR;
Schlumberger Technology Corporation, Sugar Land, TX (US);
Abstract
The present disclosure relates to determining the attenuation of an electromagnetic signal passing through a conductive material. An antenna is provided and placed in relatively close proximity to the conductive material. An alternating current is passed through the antenna and the impedance of the antenna is measured. The attenuation is determined using the measured impedance. A single frequency measurement may be made, or multiple measurements using different frequencies may be made. Grouped parameters based on properties of the material and the frequency of the current are used to relate the coil impedance to the attenuation. A current frequency for which the ratio of the antenna's resistive part of the impedance to the angular frequency of the current is substantially insensitive to at least one of the parameters is preferred.