Propagation of Electromagnetic Waves in a Non-Uniform Cold Magnetoplasma
Until now we have considered waves in a uniform magnetoplasma. In the magnetosphere the ion and electron densities and the magnitude and direction of the magnetic field are functions of position. The general problem of solving the wave equation in such a medium is very difficult and is often intractable analytically so that numerical techniques must be used. If, however, the scale on which the plasma parameters vary is large compared with the wavelength then a variety of approximate methods can be used. In this book we shall confine ourselves to waves where this is possible. Methods of solving the more general problem numerically in a plane stratified medium are discussed in detail by Budden [17, 19] with particular application to radio waves in the ionosphere. Except in the ionosphere and within field-aligned irregularities in the magnetosphere the plasma parameters vary on a length scale comparable with the earth’s radius and it is only for such wavelengths that our treatment breaks down.
Unable to display preview. Download preview PDF.