Section 5 — Set Measurement Options120WindowingMeasured data is NOT usually used directly to generate a spectrum. It isfirst modified using a Window function. The purpose of windowing is tocompensate for certain FFT algorithm limitations that cause signalleakage. Windowing involves multiplying blocks of data values by asuitable mathematical function (window type). This ensures the datablock begins and ends with zero amplitude and makes the data blockdisplay as a complete wave.NOTE: Windowing is NOT available with waveforms.Choose Window TypeYou can choose a Hanning or Rectangular (no window) window type.Each type of window has characteristics that make it better suited forsome applications and less well suited for others. The following table is ageneral guide only. You should match the window type to the nature ofthe signal you are trying to capture (e.g. random or transient signals).Window Type PurposeHanningwindowProvides the best frequency resolution. The Hanningwindow is a good general purpose window.Rectangular The FFT is NOT adjusted (i.e. this is equivalent to NOTusing a window).Waveform ParametersThis section provides more information on the available waveformparameters:• Equivalent Fmax• Number of Samples• Duration
