The Compression Algorithm for the Data Acquisition System in HT-7 Tokamak

• Published in: Plasma science & technology Vol. 5; no. 5; pp. 1939 - 1944
• Main Authors: Lin, Zhu, Jiarong, Luo, Guiming, Li, Dongli, Yue
• Format: Journal Article
• Language: English
• Published: IOP Publishing 01.10.2003; Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China
• Subjects: HT-7 tokamak; data compression algorithm
• ISSN: 1009-0630
• DOI: 10.1088/1009-0630/5/5/002

O4; HT-7 superconducting tokamak in the Institute of Plasma Physics of the ChineseAcademy of Sciences is an experimental device for fusion research in China. The main task of thedata acquisition system of HT-7 is to acquire, store, analyze and index the data. The volume ofthe data is nearly up to hundreds of million bytes. Besides the hardware and software support, agreat capacity of data storage, process and transfer is a more important problem. To deal withthis problem, the key technology is data compression algorithm. In the paper, the data formatin HT-7 is introduced first, then the data compression algorithm, LZO, being a kind of portablelossless data compression algorithm with ANSI C, is analyzed. This compression algorithm, whichfits well with the data acquisition and distribution in the nuclear fusion experiment, offers a prettyfast compression and extremely fast decompression. At last the performance evaluation of LZOapplication in HT-7 is given.