Optical Frequency Comb Generation And Its Applications In Microwave Photonics

With the development of the technology of the modern communication and network, the request of video transmission, HDTV, and super computer become more and more, which makes the request of the information explosively grows. The development of information technology pushes the development of microwave communication and optical communication which puts the advantages of microwave and optics and an new area was formed: Microwave Photonics. Optical frequency comb(OFC) is a necessary part of the optical arbitrary waveform generation and photonic signal processing in Microwave Photonics. So the generation of optical frequency comb is very important for the development of the Microwave Photonics.This thesis proposes and demonstrates new approaches and ideas in the generation of OFC and its applications in Microwave Photonics, such as pulse microwave generation and phase stable radio distribution over fiber., the main works are taken in the following aspects: A flat OFC generation scheme using a polarization modulator and a Mach-Zehnder interferometer is proposed, OFCs with up to 11 comb-lines are generated with good flatness and tunable frequency spacing.A two-stage OFC generator is proposed based on two polarization modulators(PolMs) and a Mach-Zehnder interferometer(MZI). The second-stage OFC generator using another PolM increases the comb-line number by a factor of up to 5 theoretically.A novel approach to generating an OFC based on stimulated Brillouin scattering(SBS) in optical fiber is proposed using a stocks wave recycling loop. An OFC with a frequency spacing of 9.5 GHz is generated. The comb line number is increased from 6 to 9 by using the stocks wave recycling loop. A scheme for photonic generation of pulsed microwave signals with tunable frequency and phase based on optical spectral-shaping and frequency-to-time mapping is proposed. A pulsed microwave signal is generated and the phase and the frequency of the generated microwave signal can be tuned. A novel scheme for the generation of background-free pulsed microwave signals is proposed, a pulsed microwave signal is obtained and the low frequency components in the electrical spectrum is suppressed A phase stable radio frequency distribution technique is proposed and RF phase variation is successfully removed by frequency mixing based on phase conjugation.