Filtre optique à bande latérale unique auto-accordable pour les systèmes hybrides fibre-radio

A wavelength-self-tunable single-sideband filter is proposed so as to compensate for deleterious chromatic dispersion effets in fiber-radio systems. First we describe the WST-SSB filter's concept. The latter is based on dynamic Bragg gratings generated inside an InP:Fe photorefractive crystal. The device's input signal is an optical carrier modulated at a radio frequency (RF) whose spectrum is double sideband (DSB). The gratings filter this DSB signal into a single sideband signal (SSB). In addition, since the DSB input signal controls the device by generating the dynamic bragg gratings itself, the filter is wavelength-self-tunable. Second we propose a model for WST-SSB filters spectral response. Third, devices are built and characterized at both microwave and millimeter-wave frequencies. The results of these experiments confirm the filter's principle and experimental data are in good agreement with simulations. Besides, the compensation of chromatic dispersion effects is achieved thanks to WST-SSB filters. These validations are obtained by using SSB signals corresponding to 16 GHz as well as 31,5 GHz RF modulated input DSB signals. Finally, hybrid fiber-radio experiments implementing a WST-SSB filter result in eye diagram and bit error rate measurements that prove good transmission performance.