Interferometric fiber optic gyroscope based on co-packaged optics

In this study, to address the urgent need for the integration and miniaturization of interferometric fiber optic gyroscope (IFOG) systems, a highly integrated optical transceiver module was successfully developed using photonic integrated circuit (PIC) technology. The module integrates a wide-spectrum light source, 3 dB coupler, photodetector, and miniaturized transimpedance amplifier circuit. Combined with co-packaging optical (CPO) technology, the module realizes an efficient interconnection between the optical chip and the micro printed circuit board (PCB) on the same substrate. After packaging, it is only 38.2 mm × 30 mm × 8 mm. The results of the batch testing indicated that the module exhibited excellent process manufacturability and performance uniformity. The IFOG built on this module demonstrated excellent performance during testing. At 25℃, its bias stability (100 s, 1σ) reached 0.0132°/h, angle random walk was 0.00158°/√h, bias instability was 0.0038°/h, and scale factor linearity was 85 ppm. Under full-temperature conditions (−40℃-70℃), the bias stability was 0.49°/h (100 s, 1σ). IFOG based on OTM achieved navigation-grade accuracy at room temperature and tactical-grade accuracy at full temperature, and it successfully achieved precise perception of the Earth's rotation speed, further verifying its potential for navigation-grade accuracy. This study demonstrates that PIC technology is a crucial approach for driving innovation in IFOG product forms and lays a solid foundation for the development of highly integrated dedicated chips and system architectures.