Digital spectral analysis: a diagnostic for fusion research

Appropriate signal processing of data which are delivered from a hardware diagnostic device must be considered as an important part of a plasma diagnostic tool. The advantage of processing the data with a computer is that it makes the smallest possible commitment to the later analysis and thus preserves maximal flexibility. This concept also allows a considerable reduction of the actual measurement time at the fusion device. As examples several useful processing techniques, which are based upon digital spectral analysis, are presented. All examples are based on data measured in the TEXT tokamak