Measuring Signal Spectra With Multiple Signals - R&S ESR Getting Started

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R&S ESR
2. Press the "Trace Wizard" softkey.
3. For "Trace 1", press the button in the "Trace Mode" column and select "Aver-
age" from the list.
The noise component of the trace is smoothed by averaging 10 successive
traces.
4. Switch off trace averaging by pressing the button in the "Trace Mode" column
and selecting "Clear Write" from the list.
Reducing the noise by reducing the measurement bandwidth
The noise is reduced in proportion to the bandwidth by reducing the resolution
bandwidth, i.e. reducing the resolution bandwidth by a factor of 10 also reduces
the noise by a factor of 10 (which corresponds to 10 dB). The amplitude of sinus-
oidal signals is not affected by reducing the resolution bandwidth.
1. Set the resolution bandwidth to 10 kHz.
a) Press the [BW] key.
b) Press the "Res BW Manual" softkey and enter 10 kHz.
The noise decreases by approx. 25 dB compared to the previous setting.
Since the video bandwidth is coupled to the resolution bandwidth, it is
reduced to 30 kHz in proportion to the resolution bandwidth. This causes
the sweep time to increase to 3.0 seconds.
2. Reset the resolution bandwidth (couple it to the span) by pressing the "Res
BW Auto" softkey in the "BW" menu.
7.3

Measuring Signal Spectra with Multiple Signals

7.3.1 Separating Signals by Selecting the Resolution Band-
width
A basic feature of a Signal and Spectrum Analyzer is the ability to separate the
spectral components of a mixture of signals. The resolution at which the individual
components can be separated is determined by the resolution bandwidth. Select-
ing a resolution bandwidth that is too large may make it impossible to distinguish
between spectral components, i.e. they are displayed as a single component.
Getting Started 1316.3749.02 ─ 09
Basic Measurement Examples
Measuring Signal Spectra with Multiple Signals
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