Specifications
Chapter 7 49
Measuring Noise
Measuring Signal-to-Noise
Measuring Noise
measurement results:
(ESA) Press
Marker, More, Function, Marker Noise.
(PSA) Press
Marker Fctn, Marker Noise.
Figure 7-1 Measuring the Signal-to-Noise
Read the signal-to-noise in dB/Hz, that is with the noise value
determined for a 1 Hz noise bandwidth. If you wish the noise value for a
different bandwidth, decrease the ratio by . For example, if
the analyzer reading is
−70 dB/Hz but you have a channel bandwidth of
30 kHz:
NOTE The display detection mode is now average. If the delta marker is closer
than one quarter of a division away from the edge of the response to the
discrete signal, the amplitude reference signal in this case, there is a
potential for error in the noise measurement. See “Measuring Noise
Using the Noise Marker” on page 50.
10 log× BW()
S/N 70– dB/Hz 10 30 kHz()log×+ 25.23 dB– 30 kHz()⁄==