Page 363 - The ROV Manual - A User Guide for Remotely Operated Vehicles 2nd edition

Transmitter
Transmitter output
Receiver sensitivity
Power budget
Connectors
Splice
Fiber
Fiber loss
Splice loss
Distance from transmitter
Fiber loss
13.2 Transmission 355
FIGURE 13.30
Connector loss
Optical power budget and various losses between transmitter and receiver.
(with rapid development of tools and techniques for troubleshooting) field techniques allow for reli- able telemetry with subsea components.
13.2.6 Radio
As stated above, RF communications with subsea vehicles have a very limited usage due to the high attenuation of RF waves through water. However, new technologies are evolving for data transmission over short ranges through water. Look for further technological movement of subsea telemetry based upon RF as the deepwater minerals extraction industry develops automation techniques.
13.2.7 The ubiquitous decibel
The decibel (dB) is a unit of relative power. The base unit is the “bel” with the decibel as 1/10 of the unit of bel (named in honor of Alexander Graham Bell). The dB is a common unit of measure- ment and is ubiquitous in the telecommunications, electronics, and broadcasting industries.
Receiver
Margin
Link loss
20 dB total budget
Power