Tunable Frequency-doubling OEO Based On Optical-injected DFB Laser

Microwave or millimeter-wave generation is one of the most important fields of microwave photonics. Signal with high frequency, low phase noise, steady performance is widely used in various fields. As a significant research direction of signal generation, optoelectronic oscillator (OEO) has outstanding advantages and can be used in many applications of different fields. OEO is perfecting, but difficulties of high frequency extending, unstable phase noise and modes competition are still existed.This thesis mainly focuses on tunable microwave photonic bandpass filter (MPBF) and tunable frequency-doubling OEO. Before experimentally researching on MPF and OEO, we theoretically used the model of the single loop OEO to explain the basic structure, the devices, quality characterization and to simulate the phase noise, the modes competition and nonstationary steady-state behavior. Electrical bandpass filter (EBPF) traditional applied in the OEO loop limits the frequency tunability of OEO. To solve this problem, MPBF can used to replace EBPF. We than experimentally researched the tunable MPF based on optical-injected distributed feedback (DFB) laser. Under strong optical injection, the resonance frequency is induced by the coupling between photon amplitude and phase, corresponding to the frequency difference between the master laser and the red-shifted cavity mode which is controlled by the frequency detuning and the injection ratio. Adjusting the frequency detuning and injection ration, we achieved a MPF with tunable range of 25GHz. We also did some research on tunable MPF based on polarization modulator (PolM) and optical-injected DFB laser. In this structure, we realized a 30GHz tunable range. Finally, the PolM based MPF was introduced in the tunable frequency-doubling OEO, in which the PolM is worked as phase modulator (PM) and intensity modulator (IM)at the same time.