Clairet F, Ricaud B, Briolle F, Heuraux S, Bottereau C
CEA, IRFM, F-13108 Saint-Paul-lez-Durance, France.
Rev Sci Instrum. 2011 Aug;82(8):083502. doi: 10.1063/1.3622747.
Reflectometry profile measurement requires an accurate determination of the plasma reflected signal. Along with a good resolution and a high signal to noise ratio of the phase measurement, adequate data analysis is required. A new data processing based on time-frequency tomographic representation is used. It provides a clearer separation between multiple components and improves isolation of the relevant signals. In this paper, this data processing technique is applied to two sets of signals coming from two different reflectometer devices used on the Tore Supra tokamak. For the standard density profile reflectometry, it improves the initialization process and its reliability, providing a more accurate profile determination in the far scrape-off layer with density measurements as low as 10(16) m(-1). For a second reflectometer, which provides measurements in front of a lower hybrid launcher, this method improves the separation of the relevant plasma signal from multi-reflection processes due to the proximity of the plasma.
反射测量轮廓测量需要精确测定等离子体反射信号。除了相位测量具有良好的分辨率和高信噪比外，还需要进行充分的数据分析。采用了一种基于时频断层成像表示的新数据处理方法。它能更清晰地分离多个分量，并改善相关信号的隔离。在本文中，这种数据处理技术应用于来自托雷·苏普拉托卡马克上使用的两种不同反射计设备的两组信号。对于标准密度轮廓反射测量，它改进了初始化过程及其可靠性，在远刮离层中，当密度测量低至10(16) m(-1)时，能提供更精确的轮廓测定。对于在低杂波发射天线前方进行测量的第二台反射计，由于等离子体距离较近，这种方法改进了从多反射过程中分离相关等离子体信号的效果。
