Theoretical Analysis of Power-to-Temperature Coefficients of Brillouin Signals

The relation between the power of a Brillouin signal and temperature the bases of distributed fiber temperature and strain sensors based on Brillouin scattering.By now,the theoretical analysis of the temperature coefficient for the power of Brillouin signals hasn't been reported,though many experimental results have been reported.The relation between the Brillouin gain and temperature is obtained by introducing the thermal effects of Brillouin gain spectrum and the expression of Brillouin gain coefficient.Based on these analysis and steady-state Brillouin scattering equations,the temperature coefficient for the power of Brillouin signals is obtained theoretically.The results accord with the experimental results reported in other references,and the temperature coefficient for the power of Brillouin signals is position-dependent,the farther the sensing position is,the smaller the temperature coefficient for the power of Brillouin signals is.