On Measurements of Microwave E and H Field Distributions by using Modulated Scattering Methods

The modulated scattering method of Justice, Rumsey, and Richmond for measuring E field distribution is extended to the measurement of H field distribution by using a loop scatterer formed by two diodes. This diode loop method has the particular advantage of eliminating the large and undesirable effect produced by the associated E field when measuring the H field. A scattering analysis of the modulated diode loop is presented. It explains the principle of this new method and also supports the advantage mentioned above. A similar analysis for the modulated diode scatterer used in measuring E is also presented. It is believed that the explanation based upon this analysis for the E measurement is more satisfactory than that given by Richmond which is based upon a qualitative description of the diode scatterer.