Ultra long distance and high capacity optical fiber transmission system using midway optical phase conjugation

采用中途光相位共轭的超长距离大容量光纤传输系统

• 批准号: 06452240
• 负责人: KIKUCHI Kazuro
• 金额: $ 4.61万
• 依托单位: University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06452240/
• 关键词: Phase Conjugation; Optical fiber; Dispersion; Kerr effect; Optical amplifier; 四光波混合; 光通信; 分散

In an optical amplifier chain, transmission distance beyond 1,000km is attained without using regenerating rapeaters, because optical loss in fibers is periodically compensated. However, in such a system, the optical power is maintained at a high level along the entire system length and hence the Kerr nonlinearity of optical fibers can no longer be ignored. The Kerr nonlinearity, in turn, interplys with the group velocity dispersion of fibers, causing serious waveform distortion. To cope with this problem, we propose an optical transmission system using midway optical phase conjugtion, and investigate the feasibility of the system. The main results obtained in this research project are shown in the following.(1) We found that the insufficient efficiency of waveform distortion compensation was mainly caused by the sideband modulation instability originated from the periodic optical power distribution, and obtained the design rule of the system to maximize the efficiency by reducing the effiect of sideband modulation instability.(2) The optical phase conjugator using dispersion shifted optical fibers was designed. We achieved the conversion efficiency of several percent by the device fabricated according to the design.(3) The optical phase conjugator using semiconductor optical amplifiers was demonstrated. When the pump-probe detuning was 200GHz, the conversion efficiency larger than OdB was achieved. The introduction of this device into the transmission system was effective for eliminating the four wave mixing generated in optical fibers.

在光放大器链中，无需使用再生放大器即可实现超过 1,000km 的传输距离，因为光纤中的光损耗会得到周期性补偿。然而，在这样的系统中，光功率沿整个系统长度保持在较高水平，因此光纤的克尔非线性不再可以被忽略。克尔非线性反过来又与光纤的群速度色散相叠加，导致严重的波形失真。为了解决这个问题，我们提出了一种使用中途光相位共轭的光传输系统，并研究了该系统的可行性。本研究项目取得的主要成果如下：(1)我们发现波形畸变补偿效率不足的主要原因是周期性光功率分布产生的边带调制不稳定性，并得出了通过降低边带调制不稳定性的影响来最大化系统效率的设计规则。(2)设计了采用色散位移光纤的光相位共轭器。根据设计制作的器件实现了百分之几个百分点的转换效率。(3)演示了采用半导体光放大器的光相位共轭器。当泵浦探针失谐为200GHz时，转换效率大于OdB。将该装置引入传输系统，可以有效消除光纤中产生的四波混频。

项目成果

C.Lorotlanasane and K.Kikuchi: "Design of long-distance optical trans-mission systems using midway optical phase conjugation" IEEE Photonics Technology Letters. 7. 1375-1377 (1995)

C.Lorotlanasane 和 K.Kikuchi：“使用中途光相位共轭设计长距离光传输系统”IEEE 光子技术快报。

K.Kikuch et al.: "Observation of quasi-phase matched fourwave mixing assisted by periodic in a long-distance optical amplifier chain" IEEE Photomics Technal.Lett. Vol.7. 1378-1380 (1995)

K.Kikuch 等人：“长距离光学放大器链中周期性辅助的准相位匹配四波混频的观察”IEEE Photomics Technal.Lett。

K.Kikuchi,他3名: "Analysis of origin of nonlinear gain in 1.5μm semiconductor active layear by highly nondegenerate four-wave mixing" Appl.Phys.Lett.64. 548-550 (1994)

K. Kikuchi 和其他 3 人：“通过高度非简并四波混频分析 1.5μm 半导体有源层中非线性增益的起源”Appl.Phys.Lett.64 (1994)。

K.Kikuchi,他3名: "Measurement of differential gain and linewidth enhancement factor of 1.5-μm strained quantum-well active layers" IEEE J.Quantum Electron.30. 571-577 (1994)

K. Kikuchi 和其他 3 人：“1.5 μm 应变​​量子阱有源层的差分增益和线宽增强因子的测量”IEEE J.Quantum Electron.30 (1994)。

K.Kikuchi and C.Lorattanasane: "Compensation for pulse waveform distortion in ultra-long distance optical communication systems by using midway optical phase conjugator" IEEE Photonics Technol.Lett.6. 104-105 (1994)

K.Kikuchi 和 C.Lorattanasane：“使用中途光学相位共轭器补偿超长距离光通信系统中的脉冲波形失真”IEEE Photonics Technol.Lett.6。