Miniaturized High-Speed FBG Interrogator Based on a Photonic AWG Chip

Although AWGs are widely used in FBG interrogation systems, conventional interrogators are often bulky and hard to deploy, limiting their use in complex field environments. Here, we developed an FBG interrogator based on a photonic AWG chip, comprising a photonic chip module, an optoelectronic detection and processing module, and an output interface module. The AWG chip measures only 280 µm × 150 µm, while the entire interrogator measures just 160 mm × 100 mm × 80 mm, achieving system miniaturization. Wavelength interrogation tests show that the FBG interrogator achieves a wavelength accuracy of 9.87 pm and a high-speed sampling rate of up to 10 kHz, enabling high-precision, real-time FBG demodulation under rapidly varying temperatures. Furthermore, the interrogator was subjected to engineering validation, with dynamic FBG wavelength demodulation experiments conducted under high-temperature shocks in a turbo-engine, verifying its reliability under extreme conditions and demonstrating its potential for broader engineering applications.