Author: N. V. Karas
Publisher:
ISBN:
Category : Antenna radiation patterns
Languages : en
Pages : 36
Book Description
The effect of a lossless isotropic plasma on the admittance of a waveguide slot terminating in a ground plane has been studied by means of a plasma simulation technique. The relative dielectric constant between the plasma and freespace was maintained by using two contiguous real dielectric materials. Freespace was simulated by an alumina powder of high dielectric constant, and the plasma by a material of lower dielectric constant. The admittance of the slot radiator was measured by (a) a direct method, (b) Deschamps' method, (c) a tuner method. All three gave similar results. Experimental values were determined for the normalized aperture admittance of a slot covered by a simulated plasma of thickness varying from asymptotically equal to 0.1 in. to infinity. The results showed good agreement with theory. (Author).
An Experimental Study of Simulated Plasma-covered Slots
Author: N. V. Karas
Publisher:
ISBN:
Category : Antenna radiation patterns
Languages : en
Pages : 36
Book Description
The effect of a lossless isotropic plasma on the admittance of a waveguide slot terminating in a ground plane has been studied by means of a plasma simulation technique. The relative dielectric constant between the plasma and freespace was maintained by using two contiguous real dielectric materials. Freespace was simulated by an alumina powder of high dielectric constant, and the plasma by a material of lower dielectric constant. The admittance of the slot radiator was measured by (a) a direct method, (b) Deschamps' method, (c) a tuner method. All three gave similar results. Experimental values were determined for the normalized aperture admittance of a slot covered by a simulated plasma of thickness varying from asymptotically equal to 0.1 in. to infinity. The results showed good agreement with theory. (Author).
Publisher:
ISBN:
Category : Antenna radiation patterns
Languages : en
Pages : 36
Book Description
The effect of a lossless isotropic plasma on the admittance of a waveguide slot terminating in a ground plane has been studied by means of a plasma simulation technique. The relative dielectric constant between the plasma and freespace was maintained by using two contiguous real dielectric materials. Freespace was simulated by an alumina powder of high dielectric constant, and the plasma by a material of lower dielectric constant. The admittance of the slot radiator was measured by (a) a direct method, (b) Deschamps' method, (c) a tuner method. All three gave similar results. Experimental values were determined for the normalized aperture admittance of a slot covered by a simulated plasma of thickness varying from asymptotically equal to 0.1 in. to infinity. The results showed good agreement with theory. (Author).
An Experimental Study of Plasma-covered Slots on Cylinders and Cones
Author: Nicholas V. Karas
Publisher:
ISBN:
Category : Antenna radiation patterns
Languages : en
Pages : 36
Book Description
The effect of a plasma on the radiation characteristics of slot and gap apertures located on structures such as cylinders and cones has been studied by means of a plasma simulation technique. The relative index of refraction of less than unity between plasma and free space was maintained for the model by an analog tank that represented free space by a high dielectric constant liquid and the plasma by a lower dielectric material. This technique differs from a previous simulation method in that the models can be immersed into the tank, rather than being kept external. This modification allows the study of nonplanar geometries of complex shapes. Antenna patterns of axial slots on cylinders of various radii and thicknesses of plasma covering were observed to have good agreement with theory for radiation in the equatorial plane, as did the antenna patterns for a plasma-covered center-fed cylindrical antenna. Experimental patterns of a slot on a cylinder partially covered by a plasma are presented. Various effects of the plasma on the radiation characteristics of the slot were observed by varying the location of the plasma on the cylinder in relation to the slot and by varying the amount of surface area covered by the plasma. Experimental patterns of slots on cones covered by a plasma are also presented. (Author).
Publisher:
ISBN:
Category : Antenna radiation patterns
Languages : en
Pages : 36
Book Description
The effect of a plasma on the radiation characteristics of slot and gap apertures located on structures such as cylinders and cones has been studied by means of a plasma simulation technique. The relative index of refraction of less than unity between plasma and free space was maintained for the model by an analog tank that represented free space by a high dielectric constant liquid and the plasma by a lower dielectric material. This technique differs from a previous simulation method in that the models can be immersed into the tank, rather than being kept external. This modification allows the study of nonplanar geometries of complex shapes. Antenna patterns of axial slots on cylinders of various radii and thicknesses of plasma covering were observed to have good agreement with theory for radiation in the equatorial plane, as did the antenna patterns for a plasma-covered center-fed cylindrical antenna. Experimental patterns of a slot on a cylinder partially covered by a plasma are presented. Various effects of the plasma on the radiation characteristics of the slot were observed by varying the location of the plasma on the cylinder in relation to the slot and by varying the amount of surface area covered by the plasma. Experimental patterns of slots on cones covered by a plasma are also presented. (Author).
Application of Plasma Simulation to Slot and Gap Antennas
Author: Nicholas V. Karas
Publisher:
ISBN:
Category : Antennas
Languages : en
Pages : 40
Book Description
A plasma simulation technique has been applied to determine the effects of a plasma on the aperture admittance of radiators located on structures that are of a nonplanar shape. Specifically the normalized aperture admittance, with and without plasma, has been determined for a slot on cylinders of different radii, and for a cylindrical gap antenna. In addition, the plasma effects on the mutual coupling of two rectangular slots has also been found experimentally and compared to theory. All experimental results show good agreement with theory. (Author).
Publisher:
ISBN:
Category : Antennas
Languages : en
Pages : 40
Book Description
A plasma simulation technique has been applied to determine the effects of a plasma on the aperture admittance of radiators located on structures that are of a nonplanar shape. Specifically the normalized aperture admittance, with and without plasma, has been determined for a slot on cylinders of different radii, and for a cylindrical gap antenna. In addition, the plasma effects on the mutual coupling of two rectangular slots has also been found experimentally and compared to theory. All experimental results show good agreement with theory. (Author).
U.S. Government Research and Development Reports
Author:
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 616
Book Description
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 616
Book Description
Proceedings of the Third Symposium on the Plasma Sheath-Plasma Electromagnetics of Hypersonic Flight
Author:
Publisher:
ISBN:
Category : Aerodynamics, Hypersonic
Languages : en
Pages : 370
Book Description
This volume is a collection of the unclassified papers presented at the Third Symposium on the Plasma Sheath-Plasma Electromagnetics of Hypersonic Flight. This symposium consisted of the review of progress in reentry communication studies during the three year period since the prior meeting. The program of this symposium on plasma electromagnetics of hypersonic flight involves a wide range of scientific disciplines, including electromagnetics, aerodynamics, aero-thermochemistry, plasma dynamics, electronics, and high- temperature phenomena. The papers were selected to explore as many of these facets of research, including the results of laboratory, flight, and system tests, as time permitted.
Publisher:
ISBN:
Category : Aerodynamics, Hypersonic
Languages : en
Pages : 370
Book Description
This volume is a collection of the unclassified papers presented at the Third Symposium on the Plasma Sheath-Plasma Electromagnetics of Hypersonic Flight. This symposium consisted of the review of progress in reentry communication studies during the three year period since the prior meeting. The program of this symposium on plasma electromagnetics of hypersonic flight involves a wide range of scientific disciplines, including electromagnetics, aerodynamics, aero-thermochemistry, plasma dynamics, electronics, and high- temperature phenomena. The papers were selected to explore as many of these facets of research, including the results of laboratory, flight, and system tests, as time permitted.
U. S. Government Research and Development Reports
Author:
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 1174
Book Description
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 1174
Book Description
OAR Cumulative Index of Research Results
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 1264
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 1264
Book Description
Scientific and Technical Aerospace Reports
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 994
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 994
Book Description
Report on Research at AFCRL
Author: Air Force Cambridge Research Laboratories (U.S.)
Publisher:
ISBN:
Category : Geophysics
Languages : en
Pages : 400
Book Description
Publisher:
ISBN:
Category : Geophysics
Languages : en
Pages : 400
Book Description
Government Reports Announcements
Author:
Publisher:
ISBN:
Category : Research
Languages : en
Pages : 1002
Book Description
Publisher:
ISBN:
Category : Research
Languages : en
Pages : 1002
Book Description