914-Hde Optics; 914-Hde Flux Budget Calculation; Optical Safety; Table 4-9: Sample Flux Budget Calculation - Moog FOCAL 914-HDE L1 User Manual

4.8

914-HDE Optics

An SFP or SFP+ transceiver provides the optical interface for the 914-HDE. Many options exist including:

Singlemode or multimode fiber

Bi-directional 1310/1550 nm transceivers (L1 and M1 versions)

Bi-directional 1270/1330 nm transceivers (H1 version)

CWDM wavelengths (L1, M1 or H1 versions)

Non-standard optical budgets
Due to the high data rates, singlemode fiber is standard. Multimode fiber is only suitable for very short links (<
300m). Contact Moog Focal for multimode options. Typical link budgets for single mode fiber are 20dB for bi-
directional single fiber or 24dB for dual fiber CWDM. Moog Focal has compatible CWDM modules that can be
mounted and stacked with 914-HDE systems. Please refer to section 8.0.

4.8.1 914-HDE Flux Budget Calculation

When specifying an optical system, it is important to analyze system losses and fiber link distances in order to
calculate the required optical configuration. The following table shows a sample flux budget calculation for a system
with multiple ST bushings, a 10 km singlemode fiber link and a FORJ. Actual losses can vary widely from this, each
system flux budget calculation must use data based on actual parts in use.
Component
Typical Output Power
Connector
Connector
Fiber Optic Rotary Joint
Connector
Connector
Cable (for 10 km SMF length)
Connector
Connector
Total Losses
Received Power
Dispersion Penalty
Required Receive Sensitivity
Typical Receive Sensitivity
Available Margin
Assumptions:
Fiber Loss
Connector (ST/PC)
FORJ Loss (Max.)

4.8.2 Optical Safety

All lasers used in the 914-HDE system are Class I laser devices per IEC-60825 unless otherwise specified in
installation or configuration drawing. No special control measures or warning labels are required, although any
needless exposure of the eye should be avoided as a matter of good practice, and
with magnifying instruments, e.g. fiber scopes, while optical power is present.
wavelengths are in the infrared range, so not visible, but magnifying instruments can still cause damaging levels to
the eye.
Focal Technologies Corporation
A Moog Inc. Company
Model 914-X Series Modular Multiplexer System User Manual

Table 4-9: Sample Flux Budget Calculation

Uplink (1310 nm)
-1.0
0.3
0.3
4.0
0.3
0.3
4.0
0.3
0.3
9.8
-10.8 (=-1.0 dBm - 9.8 dB)
1.0
-11.8
-21.0
9.2
0.4 dB/km @ 1310 nm; 0.3 dB/km @1550 nm (single mode fiber - SMF).
0.3 dB/conn
4.0 dB
Downlink (1550 nm)
-1.0
0.3
0.3
4.0
0.3
0.3
3.0
0.3
0.3
8.8
-9.8 (=-1.0 dBm - 8.8 dB)
1.0
-10.8
-21.0
10.2
fibers should never be viewed
Note that the optical
Document Number: 914-0601-00 Rev. 5.0
Unit
dBm
dB
dB
dB
dB
dB
dB
dB
dB
dB
dBm
dB
dBm
dBm
dB
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