Sensing fiber Bragg grating(FBGs) array and reference FBGr are scanned by a tunable narrow-band light source composing a broad-band source and a tunable optical filter(TOF).Multiplexed sensing system is then demodulated by virtue of photo-detector and signal processing system.Experiments demonstrate that this demodulation scheme is feasible and higher signal-noise ratio and measuring accuracy can be acquired.Furthermore,this system has the potentiality of interrogating and modulating senor network with over forty FBGs.