支持6G时代数据中心间的高容量、高速通信
November 30, 2023
KDDI株式会社(总部位于千代田区), Tokyo; President and CEO: Makoto Takahashi, hereinafter, “KDDI”), KDDI Research, Inc. (headquartered in Fujimino-shi, Saitama; President: Hajime Nakamura, hereinafter, “KDDI Research”), 住友电工株式会社. (headquartered in Osaka City, Osaka; President: Osamu Inoue, hereinafter “Sumitomo Electric”), Furukawa Electric Co., Ltd. (headquartered in Chiyoda-ku, Tokyo; President: Hideya Moridaira, hereinafter “Furukawa Electric”), and OFS Laboratories, LLC (headquartered in United States; hereinafter “OFS”) have conducted successful experiments on ultrawideband optical fiber transmission with a transmission bandwidth of 115.2太赫兹(大约比常规c波段宽24倍), 世界上最大的传输容量:484tbps, transmission distance: 31 km) (Note 1) in optical fiber transmission experiments using standard optical fiber diameter. This was done by combining uncoupled 12-core optical fiber that has 12 independent cores densely arranged in a 250-μm coating (Note 2), 与标准光纤的尺寸相同, 宽带o波段光纤放大器(BDFA).
In the 6G era, it is expected that far more and diverse data will flow through networks than at present due to the spread of IoT (Internet of Things) devices and mobility services, 进一步扩大光纤通信容量以支持网络是十分必要的. 这次的成功在于支持高容量的技术, 6G时代数据中心之间的高速通信. Furthermore, the same transmission capacity can be secured with fewer fiber cores since the transmission capacity per optical fiber can be greatly expanded, and this technology is expected to enable the use of ordinary conduits and facilities with less space occupied.
Background: 为了支持6G时代的网络，需要进一步扩大光纤通信的容量. 采用波分复用技术一般可以提高每根光纤的传输容量, 其中光的波长稍微改变以进行多路传输. Until now, KDDI Research, Sumitomo Electric, 和古川电气一直致力于多芯光纤的实际应用, 它们在一根光纤中有多个芯 (Note 4). In March 2023, KDDI Research, Furukawa Electric, 和OFS进行了成功的o波段相干密集波分复用(DWDM)传输 (Note 5) 利用o波段的实验, 它的传输带宽大约是C波段和l波段的两倍 (Note 6). Furthermore, in March 2023, Sumitomo Electric presented a high-density uncoupled 12-core optical fiber with a coating diameter of 250 μm, 标准光纤直径相同, 使其成为制造高密度光缆的理想材料 (Note 7).
Results at time: KDDI, KDDI Research, Sumitomo Electric, Furukawa Electric, 和OFS已经成功进行了传输带宽为115的大容量传输实验.2 THz by using the high-density uncoupled 12-core optical fiber with a coating diameter of 250 μm and combining it with O-band coherent DWDM transmission technology, 这能显著降低核间串扰的影响. 详情请参阅附录.
[Appendix] Roles of individual companies
- KDDI and KDDI Research
- Furukawa Electric and OFS
WDM:波分复用器，PDM:偏振分复用
- Sumitomo Electric
The O-band has an advantage in that it can reduce the signal processing load to compensate for wavelength dispersion (Note 8) 因为波长色散的影响小于c波段的影响, but it has a drawback that the quality of the optical signal is easily degraded due to nonlinear optical effects (Note 9). Therefore, the O-band has been considered unsuitable for increasing the capacity of optical fiber communication systems. KDDI Research has developed O-band coherent DWDM transmission technology that enables high-capacity transmission by suppressing nonlinear optical effects through optimization of the transmission power of optical signals. Wavelength division multiplexing of more optical signals is effective in increasing the capacity of optical fiber communication, 但这需要能够放大更宽波段的光纤放大器. 由古川电气和OFS开发的BDFA可以放大整个o波段的光信号, 哪个比c波段和l波段加起来还要宽. This experiment showed that an ultrawideband comparable to the C+L band can be achieved by amplifying coherent DWDM signals over 9.6 THz in the O-band. Furthermore, 采用多芯光纤, 其中，在一根光纤中布置多个芯，作为光信号的路径, 每根光纤的传输容量可以通过芯数来扩展. Sumitomo Electric has focused on the fact that optical signals in the O-band are more strongly confined by the core than in the C-band, and it has developed an uncoupled 12-core optical fiber with 12 independent cores densely clustered within the standard optical fiber outer diameter of 250 μm. It was demonstrated that, 通过结合这三种技术, 每根光纤的总可用带宽可扩展到115.2 THz, 并成功进行了484tbps的大容量传输实验. This is the world’s largest bandwidth and transmission capacity in a demonstration experiment for a single wavelength band, 不是多个波段的组合.
Future outlook: In the future, 收发器的研究和开发将继续进行, optical fiber amplifiers, and digital signal processing algorithms toward the practical application of ultrawideband O-band coherent DWDM transmission systems, 目的是进一步提高数据中心之间的传输能力. Part of this research and development is the result of Project JPNP20017 commissioned by the New Energy and Industrial Technology Development Organization (NEDO), 一个国家研究和发展机构.
(Note 1)
KDDI Research于2023年10月20日进行的调查
(Note 2)
多芯光纤，包层直径标准，可使用现有光缆.
(Note 3)
截止日期后的论文:在一般论文提交截止日期(截止日期后)之后被接受的论文。. 论文选择在会议期间进行, 只有高度评价的研究结果才有机会被报道.
(Note 4)
Press release 2022年3月28日(日语)
Development and Demonstration of World-leading Technologies that Increase Submarine Optical Cable Capacity with Multicore Fiber.
(Note 5)
Coherent dense wavelength division multiplexing (DWDM) transmission: Coherent transmission is a method of transmitting a larger volume of data than conventional intensity modulation-direct detection technology by using the properties of light as waves as well as the light intensity. Dense wavelength division multiplexing (DWDM) is a method of densely multiplexing wavelengths in WDM (Wavelength Division Multiplexing) technology, 增加光纤的传输密度.
(Note 6)
Press release on May 18, 2023
Utilization of ultrawide bands to increase the capacity of optical fiber communication: The world’s first successful O-band coherent high-density wavelength division multiplexing transmission experiment.
(Note 7)
T. Hayashi, A. Inoue, Y. Suzuki, Y. Norisugi, K. Kawamoto, J. Takano, T. Nagashima, T. Hirama, K. Takeda, Y. Shimoda, and F. Sato, “Ultra-High-Density Microduct电缆，非耦合12芯光纤，标准250µm涂层,光纤通信会议(OFC) 2023, 技术文摘系列(光学出版集团), 2023), paper Tu2C.2.
(Note 8)
波长色散:光在不同波长以不同速度传播的现象. 因为光信号包含稍微不同的波长成分, 传播距离越长, 由于波长色散造成的光信号畸变越多.
(Note 9) Nonlinear optical effect: A phenomenon in which an optical signal interferes with a component of its own optical signal or a component of another optical signal multiplexed to a different wavelength, 造成光信号失真.
Inquiries:
KDDI Research, Inc. Public Relations Group
