Technical aspects of a multichannel pulsed radar reflectometer

Pulsed radar reflectometry has been proposed as a viable option for measuring electron density profile in thermonuclear plasmas. Pulsed radar is based on the measurement of the time-of-flight between launching and receiving a short (< 1 ns) microwave pulse which is injected into the plasma and reflected by the cut-off layer. The flight time is directly related to the position of the cut-off density. Density profiles can be deduced by measuring the flight times of pulses with various frequencies. Additional information about the local density gradient can be gained from the pulse shape deformation during the reflection process. 5 refs, 4 figs