The Design Of Optical Arbitrary Waveform Generation And Study Of Comb Coherent-light Source

With the development of science and the information technology, people have not beenlimited to the study of ultra-short pulses, but also its waveform, frequency tunability proposednew requirements. The optical arbitrary waveform generation(O-AWG) where ultrashortoptical pulse as input for pulse shaping, to obtain high repetition frequency of arbitrary lightwaveform, has been widely applied in high quality light producing, light informationprocessing, high-speed optical fiber communication and other aspects. How to get an opticalarbitrary waveform generation both waveform and repeat frequency can be tuned is one of thehot spots in the current study.O-AWG includes comb coherent-light source and pulse shaper. Based on spectralline-by-line shaping of the Fourier transform, we design two kinds of all-fiber, amplitude andphase controlled line-by-line pulse shaping system and experimental research for combcoherent-light source. in this paper. The detail as below:(1). Introduce the theory of optical arbitrary waveform generation by spectralline-by-line shaping which based on Fourier transform and discuss the determination ofspectrum line number, the line width and the amplitude and phase of combs impact on theoutput waveform.(2). Design the pulse shaping system based on optical fiber Bragg grating(FBG) array,which gratings in series and each PZT between gratings. This system utilizes the filteringproperties of FBG and grating reflectivity to realize wavelength selection and amplitudecontrol; Fiber delay line produced by PZT to achieve the spectrum phase control. Throughtheoretical calculations to determine parameters of the various parts of the system whenproduces Gaussian pulse sequence, and analyzes the effect of amplitude and phase changes onoutput waveform then determines the minimum waveform distortion range and thecorresponding range of spectral amplitude and phase changes(3). Design a multi-phase and multi-wavelength fiber grating pulse shaping system. Thissystem use fiber grating to realize wavelength selection, amplitude and phase control to inputcombs. With Gaussian waveform as an example, through theoretical calculation to determinethe length of each grating, center wavelength and the values of phase shift between gratings,obtaining the output of Gaussian waveform.(4). Experimental study of comb coherent-light source. Obtain frequency repetitiontunable and frequency stability comb coherent-light source, using modulation instability infiber, which as the input of O-AWG.