Fiber Bragg Grating Based Wireless Sensor Module With Modulated Radio-Frequency Signal

A fiber Bragg grating (FBG) sensing scheme based on the measurement of radio-frequency (RF) signal is presented for wireless sensing applications. A fiber ring combined with multiple sensing FBGs is proposed to form a microwave photonic notch filter based sensor module. With an additional FBG as a tunable reference element, the modulated RF signal in the sensor module is utilized to interrogate the wavelength shift of sensing FBGs. Preliminary experiments of the FBG sensor module on the strain measurement are demonstrated and show the effectiveness and flexibility of the sensing scheme.