| In all-optical packet switching (OPS), transmission and switching are carried out entirely in the optical domain and the bottleneck caused by electrical-to-optical conversion can be broken. As a key technology of all-optical packet switching, all-optical routing control includes the header synchronization information extraction, header and payload separation, header recognition, header periodic replication, control pulse broadening, payload optical buffer and so on. This dissertation focuses on the header periodic replication, header recognition and payload optical buffer, and these conclusions achieved have important reference value for implementation of all-optical routing control and development of all-optical packet switching. What I have done during the PHD period are as follows:(1) The influence of the extinction ratio (ER) of the input packet on the replicator is analyzed for the first time. The resonant characteristics of fiber ring and ER deterioration due to low input ER are derived. Using the simplified mode of replicator, the analysis of signal-to-noise ratio (SNR) deterioration due to the accumulation of ASE noise is carried out and non-circulation assistant light is introduced to suppressing the ASE noise. Control of replication number is realized and 20 replications with identity amplitude, which SNR decline less than 3dB, are realized by the power equalization based on gain saturation characteristics of SOA.(2) The optical packet replicator using cascaded SOA-based active fiber ring is proposed. In this replicator, replication number can be expressed as the product of replication number of each stage, while the ASE noise accumulation can be expressed as the sum of replication number of each stage.100 replications with identity amplitude are realized and each interval of hundreds of replications is equal accurately which reduce the phase jitter effectively.(3) Two kinds of optical XOR logic gate based on terahertz optical asymmetric demultiplexer (TOAD), which is used for NRZ code and reduces the synchronization requirements greatly, is proposed. XOR logic gate, which the control signals are introduced into SOA from two directions, is used for all-optical NRZ encryption-decryption at 2.5Gbps. Another XOR logic gate, which control signals are introduced into SOA from the same port, is realized by avoiding the competetition of two synchronized signals in SOA with DC assistant light and improving the tolerance of the control signal power with the method of confining fluctuant rang of nonlinear phase difference at optimal value of assistant light.(4) The function model of optical correlator is proposed and its performance indicators are concluded.8 bit NRZ header recognition is realized at 2.5Gbps by the optical correlator based on XOR logic. Using planar 3×3 coupler, all-optical correlator with feedback for RZ header recognition is proposed.(5) For interferometer with vertical structure based on planar 3×3 coupler, the instability of phase and polarization will inevitably impact on the performance indicators. Theoretical analysis and experiments show that symmetry of 3x3 coupler, angles in the fiber ring transfer matrix, optical fiber birefringence and the length difference of two fiber rings are the main factors which influence the polarization, and wavelength shift of light sources, length difference of two fiber rings and the changes of optical fiber refractive are the main factors which influence the phase. These measures, such as adoping fixed detachment with short optical fiber and repeatable adjustment of the polarization state, making length difference of two fiber rings as small as possible by adjusting fiber delay line, and compensating phase of the fiber ring by designing feedback circuit, can make polarization state of interference signals stable and output optical power of interference at the maximum all the time, which is important to realize the DLOB with vertical structure。...
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