Research On Photonic Generation Of Microwave Local Oscillator Signal And Waveform Signal

In recent years,the development of multifunctional integration is presented in the application of the radar,satellite communications,electronic reconnaissance confrontation and next generation broadband wireless communication.In these areas,high bandwidth,large capacity,flexible waveform generation,carrier frequency stability and high tuning flexibility are required.However,traditional electronic system is difficult to meet these requirements.Microwave photonics is a new discipline which combines microwave and optics.Compared with the traditional electronic systems,microwave photonic technology has the advantage of low transmission loss,wide bandwidth,large capacity,light weight,small size,and no electromagnetic interference.The generation of microwave signal has obvious merits based on microwave photonic.In this thesis,the research on photonic generation of microwave local oscillator signal,triangular wave and rectangular wave signal is carried out,and the main work is described as following.1.The scheme of microwave local oscillator signal generation with tunable frequency-doubled optoelectronic oscillator based on a phase modulator is proposed and experimentally demonstrated.Compared with other schemes,the proposed scheme is free from bias drift and has the merits of wide frequency tuning range and good performance on phase noise with a simple and compact structure.2.A photonic scheme to generate 12-tupling microwave LO signal based on cascading a Sagnac loop with an intensity modulator(IM)and a dual-parallel Mach-Zehnder modulator(DPMZM)is theoretically studied.The scheme can greatly improve frequency multiplication factor,besides the optical carrier and stray harmonics are restrained effectively,which can generate pure microwave even millimeter wave LO signal.3.A photonic scheme to generate triangular wave and rectangular wave signal based on a polarization division multiplexing Mach-Zehnder modulator(PDM-MZM)is studied.The scheme can avoid the use of any filter with a simple and compact structure.The scheme improved by using a balanced detector(BPD)is verified by simulation and experimentally demonstrated.The BPD can counteract the frequency component of interference and enhance effective frequency component,which is independent of modulation index.4.A photonic scheme to generate frequency-doubled triangular wave and rectangular wave signal based on a polarization division multiplexing Mach-Zehnder modulator(PDM-MZM)and a balanced detector(BPD)is proposed and verified by simulation.The scheme can generate frequency-doubled triangular wave and rectangular wave signal,which can increase the repetition rate and shorten the pulse cycle.The BPD can counteract the frequency component of interference and enhance effective frequency component,which avoids the use of frequency multiplier and complex modulator.5.A photonic scheme to generate frequency-doubled triangular wave and rectangular wave signal based on cascading an IM and a PDM-MZM is proposed and verified by simulation.With the help of polarization multiplexing signal detected by photoelectric detector independently,which is orthogonal to each other and not effected by each other,the scheme can generate frequency-doubled triangular wave and rectangular wave signal to increase the repetition rate and shorten the pulse cycle without frequency multiplier and complex modulator,which can decrease the number of electric phase shifter and reduce the demand of modulation index.6.A photonic scheme to generate frequency-doubled triangular wave and rectangular wave signal based on cascading an IM and a Sagnac loop with an IM is proposed and verified by simulation.Compared with the aforementioned scheme,the scheme has the same principle and advantages,and can reduce the number of bias with a simple modulator.