Regulation And Control Mechanisms For Optical Generation And Filter Of Microwave

The integration of optical network and wireless network develop the modern communications for the direction of large-capacity and long-distance. Radio over Fiber technology (ROF) has become a hot area of the cutting-edge research and promoted the rapid development of microwave photonics– the cross-disciplinary integration technology of microwave and photonics. The important application prospects for using advanced microwave photonics technology to solve the issue of ultra-wideband transmissions in wireless communications and military raises the prospect of great importance to all countries in the world. In this thesis, revolving around a number of key features of the physical realization in microwave photonics technology, we research related optical regulation and control mechanism, including the all-optical microwave/millimeter wave generation and microwave photonic filter.Using harmonic wave mode-locked fiber and fiber Bragg filter grating, we achieve the two output harmonic wave with frequency interval of quadruple modulator driving frequency and realize the generation of millimeter wave by bearing frequency. Through two ways: second harmonic wave mode-locked and filter extra-cavity, injection second harmonic wave mode-locked and filter inner-cavity, we achieve 40GHz millimeter-wave by using a 10GHz signal generator with phase noise of <-66dBc/Hz @ 1kHz.By introducing the optical phase shifting regulation and control mechanism in cascaded modulation, the optical carrier wave is suppressed; and combining with the regulation and control of two modulators, 2-order harmonic wave is generated and quadruple driving frequency of millimeter-wave is achieved. By using 10GHz signal generator, we achieve 40GHz millimeter-wave with phase noise of <-66dBc/Hz @ 1kHz and harmonic wave suppression ratio of >20dB.Using cascaded modulation, a reconfigurable and tunable MPF is proposed, in which the sidebands generated by a CW light passing through two cascaded MZMs serve as the multi-taps and an optical variable delay line (VDL) between two modulators is introduced to add another way to adjust the tap weightings. The reconfigurability can be achieved by adjusting both the bias voltage, modulation depth of MZMs and the difference of optical phase shifting of every sideband. So a reconfigurable MPF can be realized with arbitrary filter responses. As examples, the response shape of uniform window and hanning window are experimentally demonstrated with five taps. In addition, the tunability of MPF can also be achieved by tuning the driving frequency of MZMs. Finally, the use of fiber-optic four-wave mixing effect for a further increase in the number of the tap so that the Q value of MPF reach 20.The realization of negative coefficient taps by using birefringence effect combining with intensity modulation is also demonstrated. Through birefringence effect combining with intensity modulation, we achieved 4 and 6 tap with negative coefficient of MPF.