title: Multi-channel poloidal correlation reflectometry on experimental advanced superconducting tokamak.
abstract: A new multi-channel poloidal correlation reflectometry is developed at Experimental Advanced Superconducting Tokamak. Eight dielectric resonator oscillators with frequencies of 12.5 GHz, 13.5 GHz, 14.5 GHz, 15 GHz, 15.5 GHz, 16 GHz, 17 GHz, and 18 GHz are used as sources. Signals from the sources are up-converted to V band using active quadruplers and then coupled together. The output waves are launched by one single antenna after passing through a 20 dB directional coupler which can provide the reference signal. Two poloidally separated antennae are installed to receive the reflected waves from plasma. The reference and reflected signals are down-converted by mixing with a quadrupled signal from a phase-locked source with a frequency of 14.2 GHz and the IF signals pass through the filter bank. The resulting signals from the mixers are detected by I/Q demodulators. The setup enables the measurement of density fluctuation at 8 (radial) × 2 (poloidal) spatial points. A coherent mode with an increasing velocity from 50 kHz to 100 kHz is observed by using the system. The mode is located in the steep gradient region of the pedestal.
authors.affiliation: Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031, People's Republic of China.
authors.forename: H
authors.initials: H
authors.lastname: Qu
authors.affiliation: Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031, People's Republic of China.
authors.forename: T
authors.initials: T
authors.lastname: Zhang
authors.affiliation: Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031, People's Republic of China.
authors.forename: X
authors.initials: X
authors.lastname: Han
authors.affiliation: Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031, People's Republic of China.
authors.forename: H M
authors.initials: HM
authors.lastname: Xiang
authors.affiliation: Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031, People's Republic of China.
authors.forename: F
authors.initials: F
authors.lastname: Wen
authors.affiliation: Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031, People's Republic of China.
authors.forename: K N
authors.initials: KN
authors.lastname: Geng
authors.affiliation: Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031, People's Republic of China.
authors.forename: Y M
authors.initials: YM
authors.lastname: Wang
authors.affiliation: Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031, People's Republic of China.
authors.forename: D F
authors.initials: DF
authors.lastname: Kong
authors.affiliation: Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031, People's Republic of China.
authors.forename: J Q
authors.initials: JQ
authors.lastname: Cai
authors.affiliation: Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031, People's Republic of China.
authors.forename: C B
authors.initials: CB
authors.lastname: Huang
authors.affiliation: Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031, People's Republic of China.
authors.forename: Y
authors.initials: Y
authors.lastname: Gao
authors.affiliation: Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031, People's Republic of China.
authors.forename: X
authors.initials: X
authors.lastname: Gao
authors.affiliation: Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031, People's Republic of China.
authors.forename: S
authors.initials: S
authors.lastname: Zhang