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:
Jul. 13, 1999
Filed:
Jun. 03, 1997
Robert E Richardson, King George, VA (US);
The United States of America as represented by the Secretary of the Navy, Washington, DC (US);
Abstract
An apparatus for contactlessly measuring the electrical resistance per unit ength of a low-resistance test conductor (e.g., wire or cable) at a selected measurement frequency, which includes a coaxial cavity structure having a central cavity region defined by opposed first and second outer conductor sections, and a center conductor, wherein the test conductor comprises the center conductor. An input probe disposed adjacent to the first one of the outer conductor sections launches a standing wave on the center conductor, and an output probe disposed adjacent to the second one of the outer conductor sections senses the Q of the central cavity region. A detector coupled to the output probe measures the sensed Q of the central cavity region. The electrical resistance per unit length of the test conductor at the selected measurement frequency can be determined from the measured cavity Q. Also disclosed is an apparatus for contactlessly measuring the electrical resistance per unit length of a high-resistance test conductor, which includes a coaxial transmission line structure having an outer conductor having a central low impedance propagation region and input and output high impedance regions adjacent to opposite ends of the propagation region, and a center conductor, wherein the test conductor comprises the center conductor. An input probe disposed in the input high impedance region launches a traveling wave on the center conductor. An output probe disposed in the output high impedance region senses the attenuation of the traveling wave after it has propagated through the propagation region. First and second ferrite trap sections disposed adjacent to the input and output high impedance regions, respectively, serve to minimize the corruption of electrical resistance measurements due to electrical and/or physical phenomena which may occur in the environment external to the apparatus. A detector coupled to the output probe measures the sensed attenuation of the traveling wave. The electrical resistance per unit length of the test conductor at a selected measurement frequency can be determined from the measured attenuation of the traveling wave.