SOI-based 15-channel arrayed waveguide grating design for fiber Bragg grating interrogator

Arrayed waveguide grating (AWG) is the core component of the photonic integrated interrogation system. Its spectral characteristics will affect the wavelength interrogation performance of the photonic integrated fiber grating interrogation system. We designed, simulated and fabricated a 15-channel 400 GHz AWG based on sil-icon on insulator (SOI) substrate. The test result shows that the AWG the insertion loss is about 2.5-5 dB, the crosstalk is about-20 dB and the 3 dB bandwidth is about 2 nm. A wavelength interrogation system based on this AWG is established. According to the test results, the system has a wavelength resolution of 4 pm and an interrogation accuracy of 31.4 pm in a dynamic range of 0.8 nm. Our test result confirms that the AWG can be used as a spectral device in the fiber Bragg grating (FBG) interrogation system.