Analysis Types Visualization Printable

There are several different ZMod Analysis Types are used in Proc Spec Editor and Tornado to process raw data. For each of the available frequency domain analysis types, the FFT size is fixed at 1024 points and the window type fixed as a Hanning window.

The resulting ZMod plot is made up of 360 spectra along the x-axis and 410 frequency bins along the y-axis. The way in which the 360 spectra are chosen/constructed depends on the analysis type chosen. The differences of these analysis types are explained and an example set of data is given along with graphs of the results 

1. Standard Zmod - a quick way to process data always takes the first FFT in each spectrum. Standard ZMod analysis is most appropriate for short manoeuvres and transient phenomena and is the only analysis type suitable for phasing work between channels.
2. Spectrum with Max Peak Zmod - This processing method goes through each FFT and for that spectrum displays the FFT that saw the highest peak amplitude.
3. Spectrum with Max Energy Zmod - This processing picks the FFT with the highest total amplitude measured by summing the amplitudes across all frequency bins.
4. Average Spectra Zmod - This goes bin by bin taking the average of every FFT in the spectrum
5. Bin-by-Bin Max Peak Zmod - This processing method goes through each bin and selects the highest peak seen across all FFT's at that bin. 

Below is a basic example of data and its results based on the processing type selected. In this example each spectrum is made up of 2 FFT's with 10 bins. 

Input Data

Results