58
Calculation of optical power budget
Chapter 8
Configuring the 56/64 kbit data
communication modules
1
Calculation of optical power budget
Refer to
table 2
and
table 3
for maximum distance in a back-to-back application
Table 2:
Input data for calculation of optical power budget
Table 3:
Examples of optical power budget calculation
General data
Attenuation
Type of optical Tx/Rx-module
0
Bit rate
64 kbit/s
Transmission code
MCMI
Optical fibre
Single mode
Optical connector
FC-PC
Optical wavelength
1300 nm
Spectral bandwidth
30.0 nm
Transmitter Tx
LED
Optical min output power (S)
-22 dBm
Receiver Rx
Pin Diode
Sensitivity for BER 0 10
10
(R)
-38 dBm
Available power budget
-16 dB
Terminal equipment
Example 1
Example 2
Available power budget (S_R)
16 dB
16 dB
Equipment margin
Included
Included
Type of optical connectors
FC-PC for single mode
Terminal box
Patch panel connectors
FC-PC for single mode
0
0
Connectors for S-R
0.5 dB each
Included
Included
Total available optical power
16 dB
16 dB
Optical cable
Type of optical fibre
Single mode 1300 nm
Fibre attenuation (installed)
0.22 dB/km
0.34 dB/km
Splice attenauation
0.08 dB per splice
Av. cable length between splices
3.0 km
Average number of splices
0.33 splice/km
0.027 dB/km
0.027 dB/km
Number of repair splices
0.10 splice/km
0.008 dB/km
0.008 dB/km
Fibre margin
0.010 dB/km
0.010dB/km
Total fibre attenuation per km
0.265 dB/km
0.385 dB/km
Maximum optical transmission dis-
tance
60 km
41 km
Summary of Contents for REB 551-C3*2.5
Page 9: ...Contents ...
Page 21: ...12 Introduction to the installation and commissioning manual Chapter 1 Introduction ...
Page 27: ...18 Note signs Chapter 2 Safety information ...
Page 53: ...44 Installing the 56 64 kbit data communication cables Chapter 5 Installing the terminal ...
Page 59: ...50 Checking the binary I O circuits Chapter 6 Checking the external circuitry ...
Page 147: ...138 Repair support Chapter 16 Fault tracing and repair ...