Accession Number : ADD012802

Title :   Apparatus for Locating Passive Intermodulation Interference Sources.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE AIR FORCE WASHINGTON DC

Personal Author(s) : Mantovani,John C ; Denny,Hugh W ; Warren,Walter B

Report Date : 03 Mar 1987

Pagination or Media Count : 8

Abstract : This patent discloses an apparatus for locating passive interference sources by using a pair of different RF signals in conjunction with an acoustic signal to generate intermodulation products in metal to metal junctions. The acoustic tagging technique utilizes a focused, high power beam of acoustic energy to mechanically vibrate the suspected offending junction. This mechanical vibration causes the level of intermodulation products that are generated in the junction to become amplitude modulated at the frequency of the acoustic illumination. The detection of the Amplitude Modulation, sidebands with a low noise Radio Frequency receiver that is tuned to a particular intermodulated component, permits the offending junction to be located.

Descriptors :   *PATENTS, *ACOUSTIC DETECTION, *INTERFEROMETRY, *DEFECTS(MATERIALS), *JOINTS, *JUNCTIONS, PUMPING(ELECTRONICS), RADIO SIGNALS, ACOUSTIC SIGNALS, ACOUSTIC WAVES, ACOUSTICS, ILLUMINATION, INTERFERENCE, INTERMODULATION, LOW NOISE, MECHANICAL PROPERTIES, METALS, MODULATION, NOISE(RADIO), PASSIVE SYSTEMS, RADIOFREQUENCY PULSES, SIDEBANDS, SIGNALS, SOURCES, VIBRATION

Subject Categories : Acoustics
      Couplers, Fasteners, and Joints
      Acoustic Detection and Detectors
      Radiofrequency Wave Propagation

Distribution Statement : APPROVED FOR PUBLIC RELEASE