Radiation of monofrequency antenna in compressible magnetoplasma expressing far field as sum of modal plane waves

Radiation of an Antenna in a Compressible Magnetoplasma

This review deals with the propagation of waves, especially radio waves in the ionosphere. In the macroscopic electromagnetic theory, the mathematical structure of wave propagation problems depends entirely on the properties of the dielectric operator in a magnetically nonpermeable medium. These properties can be deduced from general discussions of symmetry and considerations of physical principles. When the medium is specifically the ionosphere, various physical phenomena may occur. Because of a large number of parameters, it is desirable to define a parameter space. A point in the parameter space corresponds to a specific plasma. The parameter space is subdivided into regions whose boundaries correspond to conditions of resonance and cutoff. As the point crosses these boundaries, the refractive index surface transforms continuously.

Propagation and application of waves in the ionosphere

Radiation field of an arbitrary antenna in a magnetoplasma

In this paper, we present the derivation of the magnetoionic dispersion equation and the corresponding index of refraction and propagation constant for characterizing wave propagation in warm plasma immersed in a uniform magnetic field. To demonstrate the effects of plasma temperature on wave propagation and attenuation, a numerical example of the developed theory has been given. It is well known that there are two forward propagating modes of cold plasma: one is weakly attenuated and the other is weakly amplified. By comparing the cold plasma complex propagation constant of the classical Appleton-Hartree theory with the propagation constant obtained for the warm plasma case, we observed that the attenuated mode is thermally enhanced while the amplification of the other mode decreases by increasing the temperature where it becomes damped beyond a certain electron thermal speed.

Microwave Propagation in Warm, Collisional Magnetoionic Media

The square of the complex transverse propagation constant in a lossy, magnetized ferrite is found to be described approximately by a circle in the complex plane when the magnetic field is varied. A graphical method for obtaining approximate values for the transverse propagation constant when the wave number in the direction of the applied field is given and real is derived here. This method is used to find The power absorbed from an incident plane wave by A semi-infinite ferrite as a function of the magnetizing field amplitude.

Electromagnetic Wave Propagation in Lossy Ferrites

The complex refractive index of a magneto-ionic medium for various directions of propagation is evaluated graphically. Most of the constructions make use of a Smith Chart on which the scales have been suitably relabeled. When the directions of propagation are longitudinal or transverse with respect to the applied magnetic field, the constructions take the losses into account. The energy transferred to the medium is characterized by conductivity coefficients that are also evaluated graphically. An overlay converts the refractive index into the reflection coefficient at a plane boundary of the medium. The indexes for propagation at an arbitrary angle with respect to the magnetic field are evaluated similarly, provided the collision frequency is very low.

W. Weeks

Papers

Charts for computing the refractive indexes of a magneto-ionic medium