Agilent Technologies 93000 SOC Series Training Manual page 580

Appendix B
Signal-to-Noise Ratio
Signal-to-noise ratio (SNR) is calculated as the ratio of the rms
value of the input signal to the rms sum of all other spectral
components below the Nyquist frequency, excluding harmonics and
DC.
Calculation of SNR
Signal-to-Noise plus Distortion
The SND compares the power of the input signal with the
combined power of the harmonics and noise.
SND is calculated as the ratio of the rms value of the input signal
to the rms sum of all other spectral components below Nyquist
frequency, including everything but DC.
Calculation of SND
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