Agilent Technologies Agilent 86120C manual

Models: Agilent 86120C

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Automatic When the signal- to- noise “auto” function is selected, the

Making Measurements

Measuring Signal-to-Noise Ratios

Location of noise measurements

Automatic When the signal- to- noise “auto” function is selected, the

interpolation Agilent 86120C first determines the proximity of any adjacent signal. If the next closest signal is ≤200 GHz (approximately 1.6 nm at 1550 nm) away from the signal of interest, then the noise power is measured half way between the two channels and an equal distance to the other side of the signal of interest. See points Pn1 and Pn2 in the following figure.

If the closest signal is more than 200 GHz from the signal of interest, or if there is no other signals present, then the noise power is mea- sured at 100 GHz on either side of the signal of interest. The two mea- sured noise power levels are then averaged to estimate the noise power level at the signal wavelength. The noise power measurements use linear interpolation to estimate the noise power level at the signal of interest’s wavelength.

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Page 54
Image 54
Agilent Technologies Agilent 86120C manual Automatic When the signal- to- noise “auto” function is selected, the