Fiber Bragg Grating Interrogator (FBG-I)

The function of the high-speed fiber Bragg grating interrogator is to achieve precise interrogation of the center wavelength of fiber Bragg grating sensors. Based on tunable semiconductor laser swept-frequency interrogation technology, the interrogator uses all-solid-state components with no moving parts inside, offering advantages such as low power consumption, good shock resistance, and high precision. The interrogator consists of units including the laser light source, laser driver, return light receiver, and main control unit. The interrogator uses constant-current drive and constant-temperature control modules to drive the laser to emit swept-frequency laser light, which enters the fiber Bragg grating sensor through optical components such as a collimator, circulator, and coupler. After the reflected light passes through the circulator, a photoelectric conversion module converts the optical intensity signal into an electrical signal. Based on the optical intensity information of the return light at different frequencies, the main control unit uses a peak-finding algorithm to achieve interrogation of the sensor's center wavelength.