ADMITTANCE OF WAVEGUIDE RADIATING INTO PLASMA ENVIRONMENT,
Abstract
This report investigates the changes in input admittance of a rectangular waveguide terminated in a groundplane covered by a uniform plasma slab contiguous with the groundplane. Such radiators provide wide angular pattern coverage and find application as telemetry and communication antennas in reentry vehicles. Numerical calculations were performed for the case of lossless plasmas in which the electron densities are all below the critical density, i. e., the effective relative permittivity of the slab ranges between zero and unity. Curves of input conductance and susceptance for this configuration are given as a function of relative permittivity for several slab thicknesses. These admittance values are used to compute reflection coefficients and signal loss resulting from mismatch. These are also presented graphically. The calculations show that, except for thin slabs, the aperture admittance is very close to that for a slab of infinite thickness. A qualitative explanation of this effect is also given. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1963
- Accession Number
- AD0425956
Entities
People
- A. T. Villeneuve