The function of the fiber Bragg grating demodulation instrument is to precisely demodulate the central wavelength of the fiber Bragg grating sensor. The demodulation instrument is based on tunable semiconductor laser sweep frequency demodulation technology, uses all-solid-state components, and has no moving parts inside. It features low power consumption, good shock resistance and high precision.
Technical Introduction
The demodulator drives the tunable laser to emit narrowband laser. The light is directed into the fiber Bragg grating sensor by a fiber coupler. The light reflected back from the fiber Bragg grating sensor is output from the fiber coupler and enters the phototube, where it is converted into an electrical signal and collected by the demodulator. When the wavelength of the light output by the laser coincides with the spectrum of the fiber Bragg grating sensor within a certain band range, the intensity of the light reflected back by the coupler will increase significantly, thereby achieving the demodulation of the wavelength of the fiber Bragg grating sensor.
Introduction to the Host
The fiber Bragg grating demodulation instrument controls the laser to emit light of different wavelengths and collects the intensity of the returned light at different wavelengths. According to the corresponding relationship between wavelength and intensity, it performs peak fitting on the intensity data to achieve demodulation of the central wavelength of the sensor. The demodulation result is transmitted to the upper computer software via Ethernet. The technical parameters are as follows:
Technical indicators | Normal Version | Fast Version | |
Demodulation channel | 16-channel synchronous demodulation | ||
Demodulation frequency | 1Hz~400Hz | 400Hz~800Hz | |
Wavelength demodulation range | 1527nm~1567nm | ||
Resolution | 1pm | ||
Stability | ±2pm | ±3pm | |
Dynamic range | 30dB | ||
Weight | 6.7 kg | ||
Size | 480*390*87mm | ||
Software Introduction
The upper computer software provides a human-computer interaction interface to help users configure parameters and display the working status and demodulation data of the system. It mainly includes three modules: parameter configuration, central wavelength and real-time spectrum. The demodulation mode, demodulation thresholds for each channel, storage Settings and other parameters can be flexibly configured. The data spectrum of each channel can be displayed in real time. The basic functions are as follows:
※ The demodulation thresholds of all channels can be set separately.
※ The central wavelength of the channel sensor is displayed in real time and dynamically.
※ Spectral display of each channel.
※ Data is saved in real time, and the saving length and format can be flexibly set.
