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Creating and Using Math Waveforms
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CSA7000 Series, TDS7000 Series, & TDS6000 Series Instruments User Manual
H
Tek Exponential Window. The Tek Exponential window (see Figure 3--60)
was invented at Tektronix. In the time domain, it is not a symmetrical bell
shape as is the case with the other windows (see Figure 3--60). Instead, it is
exponential with a peak at the 20% position of the time domain gate. The
frequency domain shape is triangular. Use this window for impulse response
testing where the 20% position is the zero phase reference point. More of the
acquired data record length is used to capture the impulse response. Exact
details of how to compute its values were published in the article, “Impulse--
response testing lets a single test do the work of thousands” by John Pickerd
in
EDN magazine, April 27, 1995, page 95.
1
0
Amplitude
Time
--67 dB side lobe
0
--80
dB
Frequency bins
--40
Figure 3- 60: Tek Exponential window in the time and the frequency domains