Accession Number : ADD008913

Title :   Power Line Field Discrimination Method for Magnetic Sensors.

Descriptive Note : Patent application,

Corporate Author : DEPARTMENT OF THE ARMY WASHINGTON DC

Personal Author(s) : Miller,Walter E , Jr ; McKelvy,James W

Report Date : 18 Sep 1981

Pagination or Media Count : 13

Abstract : The discriminator consists of two major parts; a nonlinear filter for low level rejection, and inhibiting logic for high level rejection, of ac magnetic fields. The nonlinear filter approximately halves the frequency characteristics of a particular class of signals, while at the same time doubling the frequency of normal interfering signals. The inhibiting logic uses the known in-phase relationship to sense and reject even very large time dependent interference. However, spatially variant signals observed from near field relative motion of two orthogonal magnetic sensors with respect to a ferro-magnetic object have a near quadrature relationship that permits signal recognition even when of less amplitude than the interference. (Author)

Descriptors :   *Patent applications, *Magnetic detectors, *Jamming, *Rejection, *Power distribution, Alternating current, Magnetic fields, Orthogonality, Signal processing, Pattern recognition, Specifications, Schematic diagrams, Waveforms, Bandpass filters, Comparators, Low pass filters

Subject Categories : Magnetic & Electric Fld Detection & Detectors

Distribution Statement : APPROVED FOR PUBLIC RELEASE