| As the major source of optical communication and optic-electric sampling detection, the quality of optical pulse generated by Gain-switched semiconductor laser gets more and more attention. Jitter is one of the most important indexes of pulse quality , and affects greatly the Bit Error Rate of optical communication and the accuracy of optic- electric sampling system. The research of laser pulse jitter is popular in recent years and gets great development. In this paper, theoretical analysis and experimental research of the pulses jitter measurement of the gain-switched laser are achieved. The followings are the work done.The developed route of laser pulse jitter measurement is simply summarized at the beginning. Four kinds of method including sampling oscilloscope, phase noise, harmonic analyzing, and cross-correlation, of pulse jitter measurement are analyzed. The math model and measure principle of pulse jitter measurement using harmonic spectrum analyzing are analyzed in theory. Error in the pulse jitter measurement based on power spectrum, established by Vor Der Linder etc., is corrected. Also a math formula of universal pulse jitter measurement is deduced and numerical simulation of pulse power spectrum is done in different condition.Secondly, the experimental system of low jitter Gain-Switched laser pulse is set up. By using Sampling Oscilloscope and harmonic spectrum analysis, the pulse jitter is measured. Laser pulse with 59ps pulse-width is generated used the Fabry-Perot Laser whose center wavelength is 1550nm. Timing jitter is lowed by external injection. Amplitude noise and time based jitter is measured with Sampling Oscilloscope and harmonic analysis, and the results arecompared. The differences of pulse jitter between pulse with and without being amplified by EDFA are analyzed. These results indicate that the accuracy of the pulse jitter measurement using harmonic spectrum analysis is high in the condition that pulse width varies less.
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