Accession Number:

ADD015074

Title:

Pulsed Field System for Detecting the Presence of a Target in a Subsurface Environment.

Descriptive Note:

Patent, Filed 23 Apr 79, patented 18 Jun 91,

Corporate Author:

DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s):

Report Date:

1991-06-18

Pagination or Media Count:

8.0

Abstract:

In a method and apparatus for searching a subsurface environment to detect the presence of a target therein, an electromagnetic field is emitted which comprises successive electromagnetic pulses of selected duty cycle, the time interval between pulses comprising a zero emission interval and a sampling interval, the sampling interval following the zero emission interval, and the polarity of the pulses of the emitted field alternating at a selected alternating frequency. The emitted field is projected into the environment from a selected location, and the electromagnetic field proximate to the selected location is sampled during each of the sampling intervals to provide a train of proximate field samples. The train of proximate field samples is spectrum analyzed to determine whether or not the field proximate to the selected location contains a component having a frequency which is equal to the alternating frequency. Author

Subject Categories:

  • Magnetic and Electric Field Detection and Detectors
  • Active and Passive Radar Detection and Equipment

Distribution Statement:

APPROVED FOR PUBLIC RELEASE