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. 06, 1996
Filed:
Jun. 14, 1994
Vincent J Ellis, Stafford, VA (US);
The United States of America as represented by the Secretary of the Army, Washington, DC (US);
Abstract
A method has been developed and used to non-intrusively interrogate electronic systems in order to determine the system's characteristic response to electromagnetic energy. The method involves subjecting the system under test to two continuous wave signal sources of different frequencies fl and fh and measuring the difference frequency .DELTA.f (fh-fl) emitted from the system under test. The difference frequency, created by mixing action of nonlinear electronic components within the system, is a relative indication of the system's response to fh, fl. By incrementing the two source signals fl and fh by the same frequency step size, .DELTA.f remains constant and is measured for each fh,fl value. The compilation of amplitude measures of .DELTA.f, normalized by the corresponding amplitude measures of fh, fl, provides a relative measure of the frequency domain transfer function of the system under test. The present method is performed with the test equipment in total isolation from the system under test and may be used to quickly and cost effectively identify those frequencies to which the system under test may be susceptible.