Anritsu MS9740B - Page 232

Chapter 5 Measurement Functions
5-82
k : Correction value set by NF Cal
λsv : Wavelength of optical signal in vacuum (nm)
Δνs : Frequency bandwidth of actual resolution at Pase
measurement (Hz)
h : Planck’s Constant 6.626 × 10
–34
(J-s)
ν : Frequency of optical signal (Hz)
Res
real
: Actual resolution (nm)
c: Light velocity 2.9979 × 10
8
(m/s)
When NF Select is Total
The noise figure is calculated from the sum of noises due to four noise
sources.
))+++
(·log(10
=
4321
FF
FFkNF
vsGh
Pase
F
∆⋅⋅⋅
=
ν
1
vaPinGh
Paset
F
s
∆⋅⋅⋅⋅
=
)(2
2
2
2
lν
G
F
1
3
=
)
(
2
4
s
PinG
Paset
F
l
⋅
=
F
1
: Beat noise between optical signal and ASE optical output
F
2
: Beat noise between ASE optical output
F
3
: Optical signal shot noise
F
4
: ASE optical output shot noise
Paset : ASE optical output total power (W)
s
a
PasePaset
ν
ν
∆
∆
⋅=
9
10)
2/
1
2
1
( ⋅⋅
+
−
−
=∆ c
BPFBWBPFBW
a
svsv
ll
ν
BPFBW: Optical bandpass filter bandwidth (nm)