Development of a fast solid-state high-resolution density profile reflectometer system on the DIII-D tokamak
Development of a fast solid-state high-resolution density profile reflectometer system on the DIII-D tokamak
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DOI：
10.1063/1.1147607
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发表时间：
1997
影响因子：
1.6
通讯作者：
K. W. Kim;E. Doyle;T. Rhodes;W. Peebles;C. Rettig;N. Luhmann
中科院分区：
文献类型：
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作者：
K. W. Kim;E. Doyle;T. Rhodes;W. Peebles;C. Rettig;N. Luhmann
DIII-D托卡马克装置上的一种新的快扫、宽带调频反射计已经产生了常规的、可靠的、具有高空间分辨率（~ 1cm）和时间分辨率（~ 100 μs）的密度剖面。该系统采用固态微波源和有源四倍器，覆盖整个Q波段（33-50 GHz），并提供高输出功率（20-60 mW）。使用任意函数发生器对射频源频率进行线性化，并主动控制源的温度以减少射频频率漂移。系统硬件允许在10 μs内对射频频率进行全频带扫描，但由于数字化限制，目前使用的扫描时间为75-100 μs。通过快速频率扫描和基于数字复解调的先进信号分析相结合，提高了重建轮廓的可靠性，快速频率扫描减少了密度波动对测量的影响，先进信号分析提高了相位精度。在DIII-D托卡马克装置上安装的一种新型宽带调频快扫反射计，已获得了常规可靠的高空间分辨率（~ 1cm）和高时间分辨率（~ 100 μs）的密度剖面。该系统采用固态微波源和有源四倍器，覆盖整个Q波段（33-50 GHz），并提供高输出功率（20-60 mW）。使用任意函数发生器对射频源频率进行线性化，并主动控制源的温度以减少射频频率漂移。系统硬件允许在10 μs内对射频频率进行全频段扫描，但由于数字化限制，目前使用的扫描时间为75-100 μs。通过快速频率扫描和基于数字复解调的先进信号分析相结合，提高了重建轮廓的可靠性，快速频率扫描减少了密度波动对测量的影响，先进信号分析提高了相位精度。快速扫描系统在边缘定位过程中解决了快速变化的边缘密度轮廓。
A new fast-sweep, broadband frequency-modulated reflectometer on the DIII-D tokamak has produced routine, reliable density profiles with high spatial (⩽1 cm) and temporal resolution (∼100 μs). The system utilizes a solid-state microwave source and an active quadrupler, covering the full Q-band (33–50 GHz) and providing high output power (20–60 mW). The rf source frequency is linearized using an arbitrary function generator and the temperature of the source is actively controlled to reduce rf frequency drifts. The system hardware allows the rf frequency to be swept fullband in 10 μs, but, due to digitization limits, the sweep time used currently is 75–100 μs. The reliability of the reconstructed profiles was improved by a combination of fast frequency sweep, which reduces density fluctuation effects on the measurements, and advanced signal analysis based on digital complex demodulation, which improves phase accuracy. The fast-sweep system has resolved fast-changing edge density profiles during edge localized modes with unprecedented resolution.A new fast-sweep, broadband frequency-modulated reflectometer on the DIII-D tokamak has produced routine, reliable density profiles with high spatial (⩽1 cm) and temporal resolution (∼100 μs). The system utilizes a solid-state microwave source and an active quadrupler, covering the full Q-band (33–50 GHz) and providing high output power (20–60 mW). The rf source frequency is linearized using an arbitrary function generator and the temperature of the source is actively controlled to reduce rf frequency drifts. The system hardware allows the rf frequency to be swept fullband in 10 μs, but, due to digitization limits, the sweep time used currently is 75–100 μs. The reliability of the reconstructed profiles was improved by a combination of fast frequency sweep, which reduces density fluctuation effects on the measurements, and advanced signal analysis based on digital complex demodulation, which improves phase accuracy. The fast-sweep system has resolved fast-changing edge density profiles during edge localiz...