A demodulation system for fiber Bragg grating(FBG) vibration sensor based on amplified spontaneous emission(ASE) is studied.Using the improved light source,the degree of linear fitting is0.999 4,the linear demodulation for wavelength is realized in the linear range of 2.5 nm rising edge,and the dynamic measurement range can reach 40-50 dB.The results indicate that this demodulation system has simple structure,fast response speed and good output linearity,and is very suitable for measurement of h...