Selecting Fft Window - Hantek DSO5000BM Series User Manual

Basic Operation
1
Fundamental frequency component
Frequency component
5
2 3 4
1. Frequency at the center graticule line
2. Vertical scale in dB per division (0dB=1V )
RMS
3. Horizontal scale in frequency per division
4. Sample rate in number of samples per second
5. FFT window type
5.3.1.3

Selecting FFT Window

Using windows can eliminate the spectral leakage in the FFT spectrum. The FFT algorithm
assumes that the YT waveform repeats all the time. When the number of cycles is integral (1, 2, 3
...), the YT waveform starts and ends at the same amplitude and there are no discontinuities in
the signal shape.
If the number of cycles is nonintegral, the YT waveform starts and ends at different amplitudes
and transitions between the start and end points will cause discontinuities in the signal that
introduces high-frequency transients.
DSO5000 Series Digital Storage Oscilloscope User Manual 26