A PHOTOCONDUCTIVE PROBE FOR MEASURING ELECTROMAGNETIC FIELDS

Abstract

Probes were constructed for measuring the intensity of the electromagnetic field in which the usual connecting leads between the probe and the detector are eliminated. The new devices are modulated reradiating or scattering antennas that consist of either a small dipole (for measuring E) or a small shielded loop (for measuring H) center-loaded with a photo cell illuminated by a chopped beam of light. The modulated scattered signal from the probe is proportional to either the component of the E field which is parallel to the axis of the dipole, or to the component of the H field which is perpendicular to the plane of the shielded loop. The scattered signal is received by an additional antenna or by the same antenna as is used for transmission. The received signal is amplified by a lock-in amplifier. The same principle was applied to the measurement of the distribution of current along an antenna with arbitrary shape. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jul 25, 1962
Accession Number
AD0287035

Entities

People

  • Keigo Iizuka

Organizations

  • Harvard University

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Amplifiers
  • Detectors
  • Electromagnetic Fields
  • Electromagnetic Scattering
  • Intensity
  • Measurement
  • Scattering
  • Warning Systems

Fields of Study

  • Physics

Readers

  • Electrical Engineering
  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Optical Fiber Sensing and Electromagnetic Propagation.