Measurement Of Third-Order Intercept Distortion - UNI-T UTS1000 Series Operating Manual

4.10 Measurement of Third-order
Intercept Distortion
In the following example, sinusoidal signal (500MHz,
-10dBm) generated by signal generator 1 (Agilent E4421B),
sinusoidal signal (501 MHz, -10dBm) generated by signal
generator 1 (Agilent E4421B) as signals to be measured.
Operation steps:
1. Connect equipment
Connect output signals generated by signal generator 1 and
signal generator 2 with RF input on the front panel of
spectrum analyzer through combiner.
2. Use marker function to measure frequency and
amplitude
1) Reset instrument
- Reset PRESET key.
2) Set parameters
- Press FREQ key;
- Press [Center frequency] key, and input 500.5MHz;
- Press SPAN key;
- Press [Span] key, and input 5MHz;
- Press BW/SWP key;
- Press [Resolution bandwidth Auto Manual] key, set
resolution bandwidth in manual mode, and input 1kHz.
3) Use marker to measure frequency and amplitude
- Press PEAK key;
- Press Marker key;
- Press [Difference] key;
- Press Peak key;
- Press [Next peak] key; read value of marker, i.e.
third-order intercept distortion value.
3. Read measurement result
Measurement result is displayed in marker area on the top
of screen. Frequency and amplitude differences obtained
by measurement can be read out directly, as shown in
Figure 4-14:
Figure 4-14: Measurement of Third-order Intercept Distortion
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