Spectrum Measurements
R&S
®
ESR
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User Manual 1175.7068.02 ─ 12
a) In the "Bandwidth" menu press the "Res BW Manual" softkey and enter "100
kHz".
The displayed noise is reduced by approx. 10 dB. The signal, therefore,
emerges from noise by about 10 dB. Compared to the previous setting, the
video bandwidth has remained the same, i.e. it has increased relative to the
smaller resolution bandwidth. The averaging effect of the video bandwidth is
therefore reduced. The trace will be noisier.
Figure 6-28: Reference signal at a smaller resolution bandwidth
6.4.5
Noise Measurements
Noise measurements play an important role in signal analysis. Noise e.g. affects the
sensitivity of radio communication systems and their components.
Noise power is specified either as the total power in the transmission channel or as the
power referred to a bandwidth of 1 Hz. The sources of noise are, for example, amplifier
noise or noise generated by oscillators used for the frequency conversion of useful sig-
nals in receivers or transmitters. The noise at the output of an amplifier is determined
by its noise figure and gain.
Advanced Measurement Examples