Snr Measurement - Keysight U8903B User Manual

SNR measurement

SNR is defined as the ratio of the signal amplitude to noise amplitude. The U8903B
implementation of the SNR measurement is a closed-loop configuration in which both the
generator and the analyzer are used in the test setup. For example, channel 1 of the analog
generator and analog analyer must be used together for this measurement.
SNR is further defined by the measurement bandwidth. The measurement bandwidth is
specified by the filter selected for the audio analyzer. The SNR measurement is
accomplished by an internal routine that alternatively switches the U8903B generator
output on and off. When the U8903B output is in the off state, the U8903B output will be
terminated at the DUT input.
The SNR result can be expressed in dB (default) or as a percentage. The SNR can be
computed as follows.
SNR
SNR measurement function mode is applicable for analog analyzer only. The settings for
SNR measurement are displayed as shown in Figure 4-39.
Figure 4-39
Keysight U8903B User's Guide
rms value of signal
⎛
= 20 Log 10 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
⎝
rms value of noise
Analog Analyzer > Functions > SNR menu page 1
Audio Analyzer Measurement Functions
⎞
⎠
4
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