In distributed fiber optic sensors to generate a stimulated Brillouin scattering we insert a signal at the other end of the fiber. This signal is commonly continuous. I want to know the reason about being continuous and not pulsed. What about the common OTDR why it is pulsed in that systems?
Vincent is right in the sense that coverage of analogue wave across/along the fiber cross section/length is more than that of digital as needed to stimulate relatively high threshold Brillouin scattering.
As Vincent said, for a full scan of the sensing fiber, the probe should be a CW. To be complete: however, it may happen that one only wants to scan the end of the fiber or a section: in this case, it is interesting to pulse the probe wave, so that the depletion occuring on the pump pulse is limited, thus increasing the Brillouin SNR.
- Badges
- Science topic
- Similar topics
- Filing