MILLIMETER WAVELENGTH FOCUSED PROBES AND FOCUSED, RESONANT PROBES FOR USE IN STUDYING IONIZED WAKES BEHIND HYPERSONIC VELOCITY PROJECTILES.

摘要

Strongly focused microwave beams are being used as a plasma diagnostics tool in the determination of the magnitude and spatial distribution of ionization behind projectiles fired at hypersonic velocities into the controlled atmosphere of a flight physics range. The importance of millimeter wavelength techniques for this purpose is stressed. The design philosophy of focused plasma probes is outlined and specific details of 35and 70 Gc probes are given,together with some typical results. The conversion of such a probe into a free-space resonator in which the resolution is preserved,but in which the sensitivity is greatly improved,is discussed and some preliminary results are given. (Author)