Detrimental effect of self-phase modulation on the performance of Brillouin distributed fiber sensors.
We show that the spectral broadening of the pump pulse through self-phase modulation in a time-domain distributed Brillouin sensor has a considerably detrimental effect in the measurement, especially in the case of long distances and high-resolution pulses. Using 30 ns pump pulses with peak power of 276 mW, self-phase modulation leads to a doubling of the effective gain linewidth after some 20 km, which is equivalent to a contrast loss of 2dB in the measurement. The impact is higher for shorter pulses (higher resolution). The theoretical modeling is fully confirmed by experimental results.
EPFL Swiss Federal Institute of Technology, Group for Fibre Optics, Institute of Electrical Engineering, STI IEL GR-SCI-LT Station 11, CH-1015 Lausanne, Switzerland. stella.foalengmafang@epfl.ch
Stella M
SM
Foaleng
Félix
F
Rodríguez-Barrios
Sonia
S
Martin-Lopez
Miguel
M
González-Herráez
Luc
L
Thévenaz