De la sensibilité accélérométrique des oscillateurs optoélectroniques à la mesure dynamique de déformations dans les fibres optiques

Optoelectronic oscillators (OEO) are an alternative solution to traditional quartz oscillators for high purity frequency references generation. For the most demanding applications, the phase noise performances must be kept in harsh vibration environments. The main goal of this thesis is to understand the phase noise degradation mechanisms occurring in OEOs when they are submitted to vibrations.To do so, we performed accelerometric sensitivity measurements of an OEO by submitting one by one its components to vibrations. The phase noise degradation is mainly due to optical path elongation. We also identified other mechanisms, through an increase of optical intensity noise in the MZM, or of laser frequency noise.In a second step, we focused on the characterization of strain in optical fiber coils. We used a phase sensitive OFDR interrogator to perform measurements over 1 km with 40 cm spatial resolution, and 10 kHz refreshing rate. The results allow to better understand the optical fiber coil mechanical behavior.Finally, we carried out a dynamical test to finely analyse the mechanical response of the optical fiber under sollicitation, and quantify OFDR-based elongation measurements. This test has been dimensioned thanks to numerical simulations which predict the strain field of a metal plate including an optical fiber as a sensor. This prediction is compared to measurements of the OFDR system.