UNI-T UTS1000 Series, Руководство по эксплуатации

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- Press BW/SWP key;
- Press [Resolution bandwidth Auto Manual] key, set
resolution bandwidth in manual mode, and input 100Hz;
you can see two signals appear on the screen, as shown in
Figure 4-3; press key to continuously reduce
resolution bandwidth, and you can clearly see two signals.
4.2.2 Measurement steps to distinguish two signals
with non-uniform amplitude
In this example, we need to distinguish tw non-uniform-
amplitude signals (frequency difference: 50kHz, amplitude
drop: approx. 40dB). To distinguish two non-uniform-
amplitude signals, resolution bandwidth must be less than
frequency spacing of two signals (same with distinguishing
two uniform-amplitude signals). However, max. frequency
bandwidth for distinguishing two non-uniform-amplitude
signals is determined by rectangle coefficient of IF filter,
rather than 3dB bandwidth. Rectangle coefficient is
defined as ratio of IF filter’s 60dB bandwidth to 3dB
bandwidth, as shown in Figure 4-4:
Figure 4-3: 100Hz Resolution Bandwidth
Figure 4-4: Bandwidth and Rectangle Coefficient
Bandwidth
Bandwidth
Half-Bandwidth