Hanbit microwave plasma diagnostic system

摘要

As a part of the plasma diagnostic system for the Hanbit device, various microwave plasma diagnostic systems have been designed and developed from the initial stage of the Hanbit project. These include the interferometer, reflectometer, andelectron cyclotron emission radiometer. In this work, we present the current activities related to the development of the microwave diagnostic systems. The brief descriptions of each system are as follows. The probing wave frequency of the interferometeris 94 GHz. Two types of interferometer have been developed. One is a conventional heterodyne-type interferometer with two microwave sources (94 GHz, 94.2 GHz Gunn oscillators). The other system uses a heterodyne-type phase detection method with onemicrowave source (94 GHz, Gunn oscillator) and a single sideband upconverter. For the plasma density profile measurements, an FM-CW reflectometer with a 7-18 GHz YIG source will be installed at the Hanbit central cell. If the O-mode propagation isadopted, it can cover one half portion of the central cell plasma density profile under the density 5×10{sup}12cm{sup}(-3). A heterodyne phase detection method is also used for this reflectometer with a single sideband upconverter.