Study on adaptive dispersion equalization techniques in reconfigurable photonic netwoak

自适应均衡技术是保证高速光网络可靠运行的关键技术之一。虽然自适应均衡技术在无线通信领域已经有很长的历史，但它在光子系统中的应用才刚刚开始。与无线电通信系统不同，光纤中的传输条件相对稳定，几乎不受环境条件的影响。然而，随着比特率增加到40Gbit/S以上，传输性能对光纤特性的微小变化变得敏感，例如损耗、色散等。此外，在全光网络中，根据业务需求动态分配光路。由于连接光节点的光纤通常具有不同的光学特性，因此传输条件随着光路的重新分配而改变。在这种情况下，光纤通信系统应被视为“时变系统”。对象…更重要的是发展自适应色散均衡技术，为可重构光网络的可靠运行提供指导。为了实现这一目标，我们分四个部分进行了理论和实验研究：(1)基于光调频法的高速色散监测系统的研制；(2)基于光谱相位的光脉冲表征技术的发展及其在色散监测中的应用；(3)动态光学元件的色散评估；(4)大容量、超长距离传输系统中色散监测和实时自适应色散补偿的论证。通过这些研究，我们指出了可重构网络在服务色散监测和实时色散补偿方面可能存在的问题，并提出了解决方案。我们相信，这些结果为未来高速光网络的可靠运行奠定了自适应色散补偿技术的基础。较少

Adaptive equalization technique is one of the key technologies for reliable operation of high-speed photonic networks. Although the adaptive equalization technique has a long history in the field of radio communication, its application to photonic systems has just begun recently. Unlike radio communication systems, the transmission condition in optical fibers is relatively stable and almost immune to environmental conditions. However, as the bit-rate increases over 40Gbit/s, the transmission performance becomes sensitive to a slight change in fiber characteristics such as loss, chromatic dispersion and so on. Furthermore, in all-optical networks, the optical path is dynamically assigned depending on traffic requirements. Since optical fibers which connects optical nodes usually have different optical characteristics, the transmission condition changes with re-assignment of optical path. In this way, optical fiber communication system should be treated as "time-varying system."The objec … More tive of this study is to develop adaptive dispersion equalization techniques and show the guideline for reliable operation of reconfigurable photonic networks. In order to achieve this objective, we divided out project into the following four part and carried out theoretical and experimental studies : (1)the development of the high-speed dispersion monitor by using optical frequency modulation method, (2)the development of the optical pulse characterization technique based on spectral phase and its application to the dispersion monitor, (3)the evaluation of the dispersion of dynamic optical components, and (4)demonstration of the dispersion monitoring and real-time adaptive dispersion compensation in large capacity, ultra long-haul transmission systems. Through these studies, we pointed out potential problems on in-service dispersion monitoring and real-time dispersion compensation in reconfigurable networks and offered their solutions. We believe that these results lay the foundations of the adaptive dispersion compensation techniques for the reliable operation of future high-speed photonic networks. Less