Design and realization of a Bragg grating prism on planar integrated optical waveguides for wideband photonic true time-delay beamforming

Abstract

This thesis presents a simulation and experimental study of a true time-delay (TTD) beamforming network using a Bragg grating prism on Ge-doped silica-on-silicon planar integrated optical waveguide for application in phased array antennas (PAA). The Bragg grating prism is designed and fabricated on planar optical waveguides and the true time-delay beamforming module is implemented using the fabricated waveguide Bragg grating prism and other photonic components. When dealing with a remotely controlled PAA, the dispersive properties of a standard single mode fiber must be taken under consideration. To this effect, a simulation study has been carried out and is detailed in this thesis. The Bragg grating prism used in the beamformer is composed of chirped gratings of different lengths but of same total chirp in order to produce a true time-delay progression. Two modulation techniques are considered, single sideband (SSB) and double sideband (DSB) modulation. SSB modulation is shown to be well suited for broadband operations with little impact on the orientation of the mainlobe resulting from chromatic dispersion. (Abstract shortened by UMI.)