Interferometric optical gyroscopes provide the long-term stability required for high-accuracy navigation, yet conventional fiber-based implementations are penalized by size, weight, and power (SWaP), while MEMS gyroscopes typically fall short in bias stability. This thesis advances GCube, a hybrid tri-axis interferometric gyroscope concept that preserves fiber-optic gyroscope physics while leveraging silicon photonics for integration and manufacturability. A physics-based model of the modulation and demodulation chain is developed and experimentally validated, incorporating shot noise, thermal noise, Kerr-induced bias, and long-term drift. The model accurately reproduces the behavior of a commercial single-axis fiber-optic gyroscope, achieving an angle random walk of approximately 3.0 × 10 − 3 ∘ / h 3.0×10 −3 ∘ / h and a bias instability of approximately 2.2 × 10 − 2 ∘ / h 2.2×10 −2 ∘ /h under both square- and sine-wave biasing, thereby closing the loop between modeling and hardware validation. Building on these results, a one-axis silicon-photonics gyroscope chip is designed on the IMEC iSiPP50G platform, integrating reciprocal splitting and combination, a TM-rejecting polarization filter, a high-linearity pure-phase modulator with suppressed residual amplitude modulation, grating-coupler interfaces, and germanium photodiodes. The rotation-sensing path employs a polarization-maintaining fiber mini-coil with an outer diameter below 30 mm, driven by an external superluminescent diode. Complementing the hardware, a real-time adaptive-threshold wavelet denoising algorithm is introduced, improving the effective signal-to-noise ratio by up to 12 dB while preserving steps and fast transients. The relationship between post-processed Allan metrics and the combined sensor–algorithm chain is clarified. Collectively, these results demonstrate a credible route toward navigation-grade performance within a MEMS-class SWaP envelope and establish a validated methodology for scaling GCube to three-axis implementations.
MINIATURIZED HIGH-END INTERFEROMETRIC OPTOELECTRONIC GYROSCOPES VIA SILICON PHOTONICS / Natale, Teresa. - ELETTRONICO. - (2026).
MINIATURIZED HIGH-END INTERFEROMETRIC OPTOELECTRONIC GYROSCOPES VIA SILICON PHOTONICS
Natale, Teresa
2026
Abstract
Interferometric optical gyroscopes provide the long-term stability required for high-accuracy navigation, yet conventional fiber-based implementations are penalized by size, weight, and power (SWaP), while MEMS gyroscopes typically fall short in bias stability. This thesis advances GCube, a hybrid tri-axis interferometric gyroscope concept that preserves fiber-optic gyroscope physics while leveraging silicon photonics for integration and manufacturability. A physics-based model of the modulation and demodulation chain is developed and experimentally validated, incorporating shot noise, thermal noise, Kerr-induced bias, and long-term drift. The model accurately reproduces the behavior of a commercial single-axis fiber-optic gyroscope, achieving an angle random walk of approximately 3.0 × 10 − 3 ∘ / h 3.0×10 −3 ∘ / h and a bias instability of approximately 2.2 × 10 − 2 ∘ / h 2.2×10 −2 ∘ /h under both square- and sine-wave biasing, thereby closing the loop between modeling and hardware validation. Building on these results, a one-axis silicon-photonics gyroscope chip is designed on the IMEC iSiPP50G platform, integrating reciprocal splitting and combination, a TM-rejecting polarization filter, a high-linearity pure-phase modulator with suppressed residual amplitude modulation, grating-coupler interfaces, and germanium photodiodes. The rotation-sensing path employs a polarization-maintaining fiber mini-coil with an outer diameter below 30 mm, driven by an external superluminescent diode. Complementing the hardware, a real-time adaptive-threshold wavelet denoising algorithm is introduced, improving the effective signal-to-noise ratio by up to 12 dB while preserving steps and fast transients. The relationship between post-processed Allan metrics and the combined sensor–algorithm chain is clarified. Collectively, these results demonstrate a credible route toward navigation-grade performance within a MEMS-class SWaP envelope and establish a validated methodology for scaling GCube to three-axis implementations.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
