Optical fiber requirements for G and G Systems
With the rapid development of data communication and interconnection networks, network point-to-point, online applications, and video services have all experienced explosive growth. Massive digital media content has led to a rapid increase of 10 or even times of Internet traffic, this results in 50% ~ The speed of 80% is growing rapidly. At present, the GB system has been commercially used by major carriers. The GB system can further increase the network capacity and reduce the transmission cost per bit on the basis of GB, it effectively solves the business traffic and the increasing network bandwidth pressure faced by operators, and is expected to gradually become commercially available around 2017.
The PM-QPSK modulation technology, coherent detection technology and DSP processing technology used in the G system reduce the OSNR tolerance of the system to 10g of the same magnitude, reducing the requirements of the system for optical fiber. The research shows that in a 1000km g system, the general G.652D optical fiber can transmit more than 40% of the distance between Low Loss and ultra-low loss optical fiber cables. The ultra-low loss can extend the distance of long chains to 35-, and some lines can reduce the number of trunk stations, facilitate all-optical network construction; in some ~ In systems with around 100km long-distance optical fiber segments, the ULL optical fiber can effectively reduce the cross-segment loss.
The OSNR, noise, and non-linearity problems brought about by the G Transmission System Limit the transmission distance. According to the test results of mainstream equipment manufacturers, the transmission distance of the 1/3G system using the dual-carrier and 16QAM modulation technology is only about of that of the g system. Therefore, the construction of the high-speed system needs to comprehensively consider the system capacity and transmission distance requirements. From the perspective of transmission equipment on the line side, multi-carrier wave light source, high-order modulation, coherent detection, high-speed DSP system and error correction technology can be used to promote the development of commercial high-speed optical transmission systems. From the perspective of the link optical fiber technology, ultra-low-loss optical fiber can improve the system OSNR and effectively extend the transmission distance, which can reduce the use of electrical relay, optimize the network structure, and save construction costs.