Effect of Using a D.C. Magnetic Field in a Re-entry Plasma Sheath.

The problem considers the effect of an angular d.c. magnetic field on the radiation of a uniform magnetic ring source (slot antenna) situated on the surface of an infinitely long metal cylinder covered by a plasma sheath.
It is observed that, in a relatively high density plasma (<ohgr><SUBp>/<ohgr> > 1), the application of a static magnetic field improves the transmission of electromagnetic waves. However, it, is shown in this paper that, in a low density plasma for which <ohgr><SUBp>/<ohgr> < 1, the application of a static magnetic field may deteriorate the transmission of radio waves through the plasma. To substantiate those, statements, both theoretical explanations and numerical results are provided. The numerical results present the comparison of the intensity of the radiated fields for various situations. In absence of a static magnetic field, an increase of collision frequency increases the transmission of radio signals through the plasma, particularly when <ohgr><SUBp>/<ohgr> > 1. When a static magnetic field is present, the increase of the transmitted signal strength with the increase of v/<ohgr> through the plasma becomes noticeable particularly for v/<ohgr> > 1. [ABSTRACT FROM AUTHOR]