In SA mode , four DFT types are given for user . How to choose which type of DFT to use in the actual application?
Different DFT types , different FFT resolutions; It will affect the detector results? and thus affect the amplitude and frequency accuracy? How to evaluate the results?
Sorry for the late reply, but due to the fires in Northern California, the SA expert whom I had to consult to get more information on this topic was out of the office last week. At any rate, here is how he describes the various DFT type settings in the SA Channel:
Here is my own summary of these settings:
Point #1: if the SA channel is in coherent mode, then the DFT type is automatically set to ARBitrary.
Point #2: the other DFT type selections trade processing speed versus available resBW selections or processing speed versus resBW accuracy (the typical speed improvement that results from changing the default settings is commonly 2-5%)
Point #3: RADix is the default mode unless the channel is in Coherent mode.
Conclusion: Unless you are doing something very specialized and fully understand the SA data acquisition and processing algorithms, it is best to just use the default settings under the Advanced or Advance/Advanced portion of the SA setup dialog.