Research On Microwave Photonic Filter And Polarization Rotator Based On Microring Resonator

Microwave photonics is a new technology that combines microwave and photonics,which overcomes the serious electronic bottleneck of traditional microwave system in high frequency,wide band and high processing speed.It has been widely used in satellite,radar and electronic warfare,due to its photonic generation,high speed processing,transmission and control of microwave signals.However,conventional microwave photonics systems composed of discrete devices are large,vulnerable to environmental disturbances and high cost.Therefore,integration is the development trend of microwave photonics.The micro-ring resonator is important block in the integrated photonics domain.Because of the compact structure,small size and multifunctions,they have been widely applied in optical filter,optical modulator,optical delay line,laser and so on.Hence,it is a great significance to expand the applications of micro-ring in the integrated microwave photonics.In the thesis,we firstly propose a microwave photonic filter(MPF)based on cascaded double-ring resonators(CDRR),which can map optical filter response to microwave domain by converting the phase-modulated signal to intensity-modulated signal.The center frequency and bandwidth of the MPF can be tuned respectively by changing the coupling coefficients of cascaded double-ring resonators and laser wavelength.The proposed devices and experiment system are studied.The experiment shows that the central frequency of the MPF based on the CDRR with same radius can be tuned from 5.05 GHz to 8GHz,while the bandwidth can be tuned from 6.3GHz to 15.1GHz,the central frequency of the MPF based on the CDRR with different radius can be tuned from 3.2GHz to 4.08 GHz,while the bandwidth can be tuned from 2.7GHz to 4GHz.Then,a compact polarization rotator based on the micro-ring resonator with asymmetric waveguides structure in the coupling region is proposed.The device has the characteristics of both polarization rotator and micro-ring resonator.We establish the structure model of the device,carry on the theoretical analysis,propose and simulate the phase-coded signal generation based on the device.