OFS FlightLink™ OM3 Cable designed for commercial aircraft, is a perfect example of the application specific solutions that OFS manufactures. All fiber is manufactured at OFS and our broad portfolio of specialty materials for buffers, strength members and jackets allow us to tailor products to meet or exceed the requirements of a given application. Avionics cables whether for commercial or military avionics have stringent requirements across the board, must be fully qualified and offer long lifetime.
All users of optical fiber are familiar with 50um (OM2) graded index multimode, a standard in telecommunications local area networks. In recent years two new higher bandwidth versions were developed, OM3 and OM4 extending the reach in LAN (Local Area Network) applications to 550 meters. While there are many aircraft currently using OM2, the higher bandwidth OM3 and OM4 cables may be considered in order to future-proof aircraft systems bandwidth requirements.
Dispersion affects the length that a signal can be carried by a fiber, with dispersion increasing with fiber length. Therefore bandwidth is specified by its “bandwidth-distance product” in Megahertz-km.
- OM3 Effective modal bandwidth at 850nm – 2000 MHz-km
- OM4 Effective modal bandwidth at 850nm – 4700 MHz-km
How far can a fiber carry a specific data rate? The following chart shows the reach of OM3 and the OM4 (standard cabled fiber) at various data rates.
System Size | OM4Distance (m) | OM3Distance (m) |
100 Gigabit Ethernet | ||
850nm (100GBASE –SR10) | 1502 | 100 |
40 Gigabit Ethernet | ||
850nm (40GBASE-SR4) | 1502 | 100 |
10 Gigabit Ethernet | ||
850nm (10GBase-S) | 5503 | 300 |
1310nm CDWM lasers (10GBASE-LX4) | 300 | 300 |
1310nmserial w EDC (10GBASE-LRM) | 220 | 220 |
- Distances based on standard total connections plus splice loss of 1.5dB and cable (Telcom) attenuation of 3.5dB/1.5dB at 850/1300nm respectively.
- Assumes 1.0dB total connection and splice loss
- Assumes 3.5dB/km max cabled attenuation at 850 plus 1.0dB of total connection and splice loss.
- Information courtesy of, LaserWave® 550/300 Multimode Fiber, Copyright© 2011 OFS FITEL, LLC, OFS Marketing Communications / fiber – 116 – 1211
Which version of 50um is the right one for current and future aircraft applications?
While OM4 provides a clear advantage in increased link length in each data rate category due to its higher bandwidth, aircraft data links are shorter than LAN requirements, usually less than 50m and rarely, if ever, exceed 100m. Even at the highest data rate (100Gigabit) either OM3 or OM4 are able to provide up to 100 meters of reach.
Coming soon – FlightLink Bend Optimized SM, What Does it Offer?
Written by,
Cathy Ciardiello