Investigation Of All-Optical Clock Extraction Based On F-P Filter

In the high-speed and long-haul all-optical networks, the all-optical clock extraction technique is a very challenging and hot research area, which is the key technique for the all-optical signal processing, such as the networking synchronization and 3R regeneration and so on. The technique of clock recovery, based on Fabry-Perot (F-P) filter, for single and multi-wavelength signals has lots of merits, like simple infrastructure and short time for clock building. Moreover, the F-P filter is an optical passive tank circuit. So it can be less influenced by the environment. This dissertation mainly focuses the research on the theory foundation, parameters simulation and experimental investigation of the multi-wavelength clock extraction based on F-P filter.Through comparing the advantages and disadvantages of kinds of single and multi-wavelength clock extraction techniques and the current experimental conditions, we propose the experimental investigation of the clock recovery based on F-P filter and a single SOA. We do the numerical simulation for F-P filter's parameters by Matlab. We can choose the proper F-P filter for extracting the best clock signals based on the simulation and the experimental condition and demand. We compare the amplitude jitter of the extracted clock under different finesse and calculate their relative standard deviation (RSD). The dissertation also simulates the effects of finesse for the amplitude descent of long-continuous zeros code that is a key factor for the high-order pseudorandom code's clock extraction.For the experimental investigation, we operate the experiment of single and multi-wavelength clock extraction for 10Gbps RZ signal, and we use a single SOA to suppress the amplitude noise. After operating the back-to-back experiment, we also extract the degraded signals'clock. Through the experiment, we demonstrate the possibility of recovering the clocks of two channels 10Gbps signals with different wavelength by F-P filter and the ability of single SOA to deal with two wavelengths clocks, and the phase noise of the two extracted clocks are -82.815dBc/Hz@10kHz and -83.072dBc/Hz@10kHz.For reducing the amplitude jitter of the intensity modulated signals, we propose another method, which is based on the self-phase modulation (SPM) effect in High Non-linear fiber (HNLF) with a subsequent optical filter at the shifted frequency compared to the input clock carrier frequency. Based on the theory analysis, we demonstrate the 2R regeneration for 10Gbps RZ signal by experiment. From the eye diagram of the degraded and regenerated signals, the amplitude noises of zero and one code are suppressed obviously. And, we take the experimental research on the wavelength conversion based on the four wave mixing (FWM) in HNLF, the idler of which is filtered as the new wavelength conversion signal.