| Optical fiber communication runs to high bit rate, large capacity and longdistance, along with which polarization mode dispersion (PMD) comes to be one ofthe important factors that limit high bit rate optical communications. More and moreattentions are paid to PMD. PMD emulator is one of the important instruments whichis used in laboratory study. A Design of PMD emulator made of polarization controller using fiber squeezersis proposed in this thesis, which consists of two polarization controllers using fibersqueezers and two segments of high birefringence fibers, and is controlled by amicro-controller unit. The emulator can generate DGDs of 0~22ps in company withsecond order PMDs of 0~121ps2. Relevant time-delays are added to the program, sothat the hysteresis effect of piezoelectricity ceramics is eliminated. Software programis adopted, so that DGDs of the emulator accord withMaxwellian distribution. The polarization controller using fiber squeezers is improved under prevenientgroundworks. Restoration units are cancelled, so that the squeezers are decreasedfrom five to three. Half-wave voltage reaches 15V. Working voltage is reduced from300V to 150V. Response time is within 10μs. Controlling speed is faster than1000πrad/s. The manufactured PMD emulator has already applied to the experiment of 4×10Gb/s PMD compensation. Self-adapted PMD comensation of 40Gb/s RZ codesystem is achieved using polarization degree for the feedback signal. Bit error rates ofthe demultiplexed 10Gb/s signal are measured. Measurement results show that powercost is less than 1dB after compensation. Effect of second order PMD is improved atthe same time when fist order PMD is compensated. Satistical laws of PMD are also discussed in this thesis. An entirely stochasticmodel is proposed, which can cause complete symmetry of the three orthogonalcomponents of birefringence vector. Therefore obtained first and second order PMD IIvectors completely accord with the statisticaltheory.
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