Ultrahigh-speed optical transmission and signal processing utilizing nonlinear effects in fibers

1.利用光纤非线性特性实现超高速长距离传输的研究成果如下：（1）在一个密集色散管理（DDM）光纤环中实现了一对孤子脉冲的传输，其传输距离为12.5ps，对应于80 Gb/s的比特率，传输距离超过7, 000 km。(2)通过循环传输实验，我们证明了双孤子的存在，利用双孤子可以消除脉冲间的相互作用。我们还研究了双孤子对初始脉冲参数变化的稳定性和双孤子在WDM传输中的适用性。(3)通过数值模拟，我们已经表明，高频谱效率的孤子传输可以通过双周期色散管理和孤子传输控制的组合使用。我们还指出，采用滤波器控制的DDM孤子传输，在160 Gb/s的速率下，传输距离可达5, 000 km以上，但传输效率有限 ...更多信息 在接收端进行扩散补偿。（1）进行了准80 Gb/s的循环传输实验，证明了利用光纤中自相位调制的全光2 R再生器，可以将无差错传输距离从300公里扩展到1,000公里。(2)通过10 Gb/s的传输实验表明，基于光纤四波混频饱和的全光限幅器通过抑制非线性相位噪声，提高了DPSK传输的误码率。(3)我们提出了基于阵列波导光栅对SPM展宽频谱进行切片的信号功率到脉冲数的转换，并实现了全光两位AD转换。我们还提出并证明了使用级联光开关的光DA转换。(4)提出并论证了利用不同波长孤子碰撞产生的时间位移实现全光可变延迟的方法。少

1. Achievements relating to ultrahigh-speed long-distance transmission utilizing fiber nonlinearities are as follows :(1) We have demonstrated transmission of a pair of soliton pulses with separation of 12.5ps, corresponding to a bit rate of 80Gb/s, over more than 7,000km in a densely dispersion-managed (DDM) recirculating fiber loop.(2) We have experimentally demonstrated the existence of bi-solitons, with which pulse-to-pulse interaction is eliminated, by a recirculating transmission experiment. We also examine stability of bi-solitons against variations in initial pulse parameters and applicability of bi-solitons in WDM transmission.(3) By numerical simulations we have shown that high spectral-efficiency soliton transmission can be obtained by a combined use of doubly-periodic dispersion management and soliton transmission control. We have also shown that DDM soliton transmission with filter control realizes distance more than 5,000km at 160Gb/s but with limited effectiveness of dis … More persion compensation at the receiver end.2. Achievements relating to optical signal processing utilizing fiber nonlinearities are as follows :(1) We have carried out quasi-80Gb/s recirculating transmission experiment and have shown that error-free transmission distance can be extended from 300 to 1,000km by the use of an all-optical 2R regenerator based on self-phase modulation in a fiber.(2) We have shown through a 10Gb/s transmission experiment that an all-optical limiter based on saturation of four-wave mixing in a fiber improves BER of DPSK transmission through suppression of nonlinear phase noise.(3) We have proposed signal power to pulse number conversion based on slicing of SPM-broadened spectrum by an arrayed waveguide grating and have demonstrated all-optical two-bit AD conversion. We have also proposed and demonstrated optical DA conversion using cascaded optical switches.(4) We have proposed and demonstrated all-optical variable delay method using temporal shifts produced by collisions between solitons with different wavelengths. Less