Anritsu MS9740B - Page 176

Chapter 5 Measurement Functions
5-26
When Point is set to Right, the position is at the dip level on the
longer wavelength side of the optical signal.
When Point is set to Higher, the position is at the higher level of the
dip points on the left or right side of the optical signal (left in Figure
5.5.3-3 (a)).
When Point is set to (L+R)/2, the position is at the average of the
levels of the dip points on the left and right sides of the optical signal.
Figure 5.5.3-3 Measurement of Noise at Noise Position
● Point:
Noise level detection position when Detection Type is Point
Higher: Higher level at left or right side of signal
wavelength
Left: Signal left side (short wavelength side)
Right: Signal right side (long wavelength side)
(L+R)/2: Average level of Signal left and right sides
● Area:
Fitting curve calculation range when Detection Type is Area
Fitting Curve: Type of fitting curve
Linear: Linear equation for noise linear data
f (λ) = aλ + b
Gauss: Binomial equation for noise log data
f (λ) = aλ
2
+ bλ + c
3rd POLY: Third-order polynomial equation for noise linear
data
f (λ) = aλ
3
+ bλ
2
+ cλ + d
4th POLY: Forth-order polynomial equation for noise linear
data
f (λ) = aλ
4
+ bλ
3
+ cλ
2
+ dλ + e
Wavelength (nm)
Level
(a) Noise Position Of
f
l
s
Left
Noise level
(b) Noise Position On
Right
Noise level
Wavelength (nm)
Level
l
s
−∆l l
s
Left
Noise level
Right
Noise level