Study On Key Technologies Of Microwave Photonic Signal Generation And Processing

As a new subject developed in recent years--Microwave Photonics, it has the advantages of the microwave technology and photon technology. Using optoelectronic devices instead of traditional electronic devices in the microwave photonics system, overcome traditional electronics of electronic bottleneck. It has many advantages over the conventional electronics microwave system, such as immunity to electromagnetic interference(EMI), low loss, small size, large bandwidth and light weight, etc.The general concept of a microwave photonic filter(MPF) is a digital filter technology which can filter microwave and radio frequency signals directly in optical domain. Microwave photonic filter become an important research content in microwave photonics. Compared with conventional microwave filters based on electrical components, it has the advantages of high bandwidth, frequency dependent losses, flexibility in design and inherent compatibilities with optical fiber microwave systems.In this dissertation, the work is mainly about using the advantages of photon technology generates microwave photonic signal. Meanwhile, apply the microwave photonic filter to the signal processing.In the part of the microwave photonic signal processing, the working principle of the MPF and the implementing scheme, and the hot issues in the design, that the realization of the negative coefficient, high Q factor, and the tunable method are presented, and then several typical microwave photonic filter structure are analyzed.,such as the MPF based on the laser array, the MPF based on chirp FBG, the MPF and based on the fiber loop.In the part of the special structure design research, a tunable and multiband bandpass microwave photonic filter(MPF) is designed. The proposed MPF is based on a fiber loop which mainly includes the semiconductor optical amplifier(SOA),tunable optical filter(TOF), optical isolator, circulator and optical coupler(OC). By adjusting the gain of the SOA, splitting ratio of the OC and the length of the fiber loop can change the frequency response of this MPF flexibly; and by adjusting the TOF, it can easily change the wave length of the microwave photonic signal.In the part of the MPF applications research, from the view of signal processing in the frequency domain, a scheme for the single mode optoelectronic oscillator based on a tunable microwave photonic filter is analyzed and demonstrated. The center frequency of the single-mode outputs is 20-GHz with well side-mode suppression ratio. Furthermore, another scheme for the rational harmonic mode-locked laser(RHMLL) based on the MPF is also demonstrated, that could be used for the amplitude equalization of the output Impulse train. The works of this dissertation is also enriched the applications aspects of the MPF. It has a well reference for the microwave photonic signal processing technology and related applications.