K
2
LAN ¼
T
À4
1 D 01
F
2
À F
2
00L À jF 1=T 0F
ð
Þþ 1=T 1
ð
ÞÀG 0 N 00
½
Š À σ EL
2 ,
ð6:106Þ
K
2
LPN ¼
D 11
FT 1
j
j
2
þ
T
À4
1 D 22
F
2
À F
2
00L À jF 1=T 0F
ð
Þþ 1=T 1
ð
ÞÀG 0 N 00
½
Š
2 :
ð6:107Þ
Then the PSD of amplitude and phase noiseS L Re ¼ K
2
LAN S SL Re , S LIm ¼
K
2
LPN S SLIm .
The PSD function of the OEO phase noise Eq. (5.79) can be presented as:
S ¼
K
2
ΓPN C A hνN sp
P 0G
,
ð6:108Þ
where C A is the constant coefficient, K
2
ΓPN (6.79) is the coefficient depending upon
the delay time in the optical fiber and upon the laser optical power.
Figures 6.33 and 6.34 show the plots of the transfer function of the laser K
2
LPN ,
which are determined of its PSD of the amplitude noise, the noise suppression
Fig. 6.33 The laser transfer function, which defines of its PSD of the amplitude noise, the noise
suppression coefficient of RF oscillations in OEO for different levels of the relative laser phase
noise (RIN-1 and RIN-2). (a) FT FOS ¼ 7, (b) FT FOS ¼ 1, (c) FT FOS ¼ 7, (d) FT FOS ¼ 2.
Calculations are executed using (6.79) and (6.107) for K
2
ΓPN and K
2
LPN . The frequency of the laser
natural relaxation resonance is equal to F 00L ¼ 2/T 1
6.7 Formation of the OEO MZ Oscillation Spectrum
359