Initial results of AM reflectometory on CPD

The amplitude modulation reflectometer system has been developed to measure the density profile in detail on the compact PWI (plasma-wall interaction) device (CPD) experiments. The probing frequency range was 6-18 GHz, and its frequency-switching time was 10 mus in an arbitrary step. Using the broadband fast-scanning reflectometer, the wide-range density profile can be measured with high time resolution. In X-mode reflectometory, the developed system successfully measured the phase delay of propagating waves at 6.6, 8.8 and 13.2 GHz, reflected at the vessel wall of the CPD and the R-cutoff layers in the CPD plasma.