Research Of All-Optical Logic Gates Based On Nonlinear Effects Of Fiber

All optical network(AON) has so many incomparable advantage compared to traditionalcommunication network, if AON want to complete the function of optical informationtransmission and exchange of routing in the optical domain,it needs optical devices. The opticallogic gates is an important component of optical signal processing, it has far-reaching influenceon future optical packet switching, all-optical wavelength conversion and so on. Due to the highnonlinear fiber has many advantages, sucn as fast response, high work efficiency and goodnonlinear characteristics, so in the domestic and foreign research domain, all-optical logic gatesbased on nonlinear optical fiber are popular.The thesis studies all-optical logic gates based on HNLF, discusses several importantnonlinear effects in optical fibers, and simulates several schemes of all-optical logic gates. Themain contents are listed as follows:(1) With the nonlinear polarization rotation(NPR) effect in nonlinear fibers, a novel highspeed all-optical XOR gate scheme is proposed. Simulates the syetem with the optical simulationsoftware Optisystem to obtain a10Gbit/s all-optical logic XOR gate. According to the simulationresults, we discuss the parametes witch effects the logic gate performance, such as the rate, pumppower, fiber nonlinear coefficient and the length.(2) With the XPM effect in nonlinear fibers, a novel high speed all-optical AND gatescheme is proposed. Through numerical simulation, a10Gbit/s all-optical logic AND gate isrealized, and the affection to the AND output is also studied, such as pump power, initial pulsewidth and signal wavelength. Simulates the syetem with the optical simulation software. Changethe signal initial phase shift, another all-optical XOR is realized. We can found, due to thedestructive interference process is not completely, there is some redundant pulse on the “0”pattern, In orde to eliminate these pulse, we design a optimization scheme baesd on Kerr switch at the output of the BPF.(3) Through basic logical oprations, a reconstructive all-optical OR gate is realized based onthe all-optical XOR gate. We simulates the syetem with the optical simulation software, andanalyzes the simulation results.