title: A 16-channel heterodyne electron cyclotron emission radiometer on J-TEXT.
abstract: To study equilibrium temporal dynamics and the mechanisms of magnetohydrodynamic instabilities, a 16-channel heterodyne electron cyclotron emission (ECE) radiometer has been developed to view the J-TEXT tokamak from the low field side. The ECE radiometer detects second-harmonic extraordinary mode in the frequency band of 94-125 GHz which corresponds to resonances from 1.8 T to 2.2 T. This ECE system consists of an ECE transmission line, a radio frequency unit, and two 8-channel intermediate frequency units. An in situ blackbody calibration source is applied for system calibration by comparison of hot and cold sources in order to provide an absolute temperature measurement.
authors.affiliation: State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China.
authors.forename: Z J
authors.initials: ZJ
authors.lastname: Yang
authors.forename: P E
authors.initials: PE
authors.lastname: Phillips
authors.forename: G
authors.initials: G
authors.lastname: Zhuang
authors.forename: J S
authors.initials: JS
authors.lastname: Xiao
authors.forename: H
authors.initials: H
authors.lastname: Huang
authors.forename: W L
authors.initials: WL
authors.lastname: Rowan
authors.forename: Z J
authors.initials: ZJ
authors.lastname: Wang