User’s Manual UTS1000B/T Series
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Measurement of Low Level Signal
This chapter will describe how to measure the low level signal and how to distinguish it from noise in the
same spectrum. The main method to measure the low signal as follows.
Reduce Input Loss
The spectrum analyzer's ability to measure low level signal is limited by the noise it generates internally.
Input attenuator will affect the level when it passes through a spectrum analyzer, if a signal is much closed
to ground noise, reduce input loss to distinguish the signal from noise.
Caution
RF IN port on the front panel can only withstand an input signal power of no more than +30dBm or a DC
voltage input of 50V. Otherwise, it may cause damage to interior circuit.
1. Press [Default]>Reset to reset spectrum analyzer.
2. Set the frequency and amplitude of signal source to 300MHz, -80dBm, connect RF OUT port of signal
generator to RF IN port of spectrum analyzer and turn on signal output.
Figure 3-10 Instrument Setting for Acquire Single Signal
3. Set the center frequency, sweep span and reference level:
Press [FREQ]>Center Frequency>300MHz
，
Span>5MHz
Press [AMPT]>Ref Level> -40dBm
4. Move all the required peak (this example is 300MHz) to the center of the screen:
Press [Peak]>Marker
→
>CF
5. Decrease the sweep span to 500kHz
（
as shown in Figure 3-11
）；
Press [FREQ]>Span>500>kHz
6. Set attenuation to 20dB:
Press [AMPT]>Attenuation>20>dB
