Investigation Of Optical Decision Based On Semiconductor-Fiber Ring Laser

In the switched network with large capacity, some problems, such as introducing crosstalk, wastage, dispersion, nonlinearity, and so on, might emerge, due to the reason that the signal should experience a long-distant transmission and exchange or cross-linking at the pitch points. These problems will lead to the change of the strength, phase and form of the optical signal. Therefore, the 3R regeneration (Re-amplifying, Re-timing, Re-shaping) dispose is needed for the optical signal. And as the core technology of 3R regeneration, all-optical decision has great researching significance. This thesis implements theoretical analysis and experimental research deeply into the optical decision technology based on the fiber ring laser.The researching results of this thesis can be described as follow:1) It analyzed the in-out features of the semiconductor optical amplifier (SOA) and the quiescent point of the fiber ring laser. And with the use of the graphical method, it imitated the processes of start-oscillation and inhibition. Also, this thesis summarized the relationship between the decision threshold and elements such as drive current of SOA and the reaction coefficient of the laser, according to which the adjustable function of the threshold can be realized.2) It imitated the wave forms of rising and falling edges of the decision output signal, and also provided the ways of decreasing the reaction coefficient of the laser, amplifying the power of the inject light, minishing the length of the ring, and so on, to increase the response speed of the decision device.3) The researcher used the decision device with fiber ring laser to implement the decision experiment to the digital signal light with noise and succeeded in modifying the amplitude shakes of the signal. And in this thesis, the reasons why the practical wave form of rising edge was different from the theoretical one were explained, and the instant amplification characteristic of S-FRL at the starting point was presented.