Development of Advanced Millimeter - Wave Plasma Diagnostics

在本研究期间，在国际合作计划下，研究了以下主题。(1)毫米波二维成像阵列的研制毫米波二维成像阵列已应用于GMMA 10串列反射镜。成像阵列成功地测量了电子密度和电子回旋辐射（ECE）的三维轮廓。ECE成像也已应用于荷兰RPT托卡马克装置，用于研究电子温度分布和温度起伏。B）Teratec公司研制了一种采用MMIC技术的新型探测器。在70-140 GHz范围内对探测器的外差特性进行了评估。实验结果表明，该探测器的中频响应范围可达8-10 GHz，比混合探测器的中频响应范围宽一个数量级。点源的Airy斑图 ...更多信息 在140 GHz处的放大系数和放大系数与设计值吻合较好.超短脉冲反射计的发展a）使用65 ps FWHM和8 V脉冲进行了超短脉冲反射计的原理验证实验。飞行时间的观测值与使用Abel反演的干涉测量数据的分布计算值吻合得很好。B）建立了毫米波诊断的二维模拟器模型，该模型可以描述寻常模和非常模的传播、反射和交叉极化散射.交叉极化散射（CPS）诊断内磁起伏方法的建立a）用超短脉冲作为入射波，在伽马10上进行了CPS实验。壁面反射的影响可以通过飞行时间测量来消除。接收到的飞行时间与考虑由磁波动引起的模式转换的计算结果一致。B）基于模拟器模型，利用异常模式反射计和CPS诊断进行了磁场重建的模拟。计算结果与实验结果进行了比较。少

During the period of this research, following subjects were studied under the international collaboration program.(1) Development of millimeter-wave Imaging Arraya) Millimeter-wave two dimensional imaging array has been applied to the GMMA 10tandem mirror. The imaging array successfully measures the three-dimensional profiles of electron density and electron cyclotron emission (ECE). The ECE imaging has also been applied to the RPT tokamak in the Netherlands for the study of electron temperature profiles and temperature fluctuations.b) A novel detector using MMIC technology has been fabricated Teratec Corporation. The heterodyne characteristics of the detector were evaluated at 70-140 GHz. The response of intermediate frequency up to 8-10 GHz was confirmed, which is one order broader than that of a hybrid detector.c) The optics for ECE imaging on Large Helical Device (LHD) were designed and fabricated by using the similar method as the GAMMA 10 system. The Airy pattern of a Point sourc … More e and the magnification factor at 140 GHz were in good agreement with the designed values.2. Development of ultrashort-pulse reflectometrya) The proof-of-principle experiment of an ultrashort-pulse reflectometry using a 65 ps FWHM and 8 V impulse has been carried out. The observed values of time-of-flight agreed well with calculated ones using the Abel-inverted profile from the ineterferometry data. The possibility of simultaneous measurements of density profile and density fluctuations was demonstrated using high repetition of the impulse generator.b) Two-dimensional simulator models to investigate millimeter-wave diagnostics has been presented, which can describe propagation, reflection, and cross-polarization scattering of the ordinary and extraordinary modes.3. Establishment of cross-polarization scattering (CPS) method for diagnostics of internal magnetic fluctuationsa) The CPS experiment has been carried out on GAMMA 10 by using an ultrashort pulse as an incident wave. The effect of wall reflection can be eliminated by the time-of-flight measurements. The received time-of-flight were consistent with those calculated considering mode conversion by magnetic fluctuations.b) The simulation of magnetic field reconstruction by using extraordinary-mode reflectometry and CPS diagnostics has been performed base on the simulator model. The results was compared with the experimental results. Less