High-stability AWG-FBG demodulation system based on temperature control and compensation algorithm

Abstract To address thermal drift and reduced demodulation accuracy in arrayed waveguide grating (AWG)-based fiber Bragg grating (FBG) demodulation systems over wide ambient temperature ranges, this study proposes an AWG demodulation system integrating thermoelectric cooler temperature control with a temperature compensation algorithm. Through the synergy of hardware temperature control and algorithmic compensation, the temperature-induced drift of the AWG channel wavelengths is effectively suppressed. In addition, sliding window filtering with a centroid demodulation algorithm is employed to achieve highly stable and continuous demodulation of the FBG center wavelength. Under ideal operating conditions, the proposed system achieves a demodulation accuracy of 2.6 pm and maintains an accuracy of 11.1 pm over a temperature range of −10 °C to 40 °C, representing an approximately 31-fold improvement compared with the system without temperature control and compensation. These results confirm the system’s high accuracy and long-term stability under complex thermal conditions, demonstrating its suitability for reliable, compact, and integrated sensing applications.