Broadband Access Network WDM-PON technology advances rapidly

Broadband access network development is very rapid, but also led to the rapid development of WDM-PON technology, may be many people do not know the development of WDM-PON technology and the future direction, there is no relationship, after reading this article you must have a lot of GAINS, I hope this article will teach you more things. The Passive Optical Network PON technology has received great attention in the industry over the past two years. Due to its superior performance in broadband access networks and its advantages in resource utilization, FTTx technology has been widely used today. Disputes over the advantages and disadvantages of different standards of PON technology are also frequently reported. Who is the most mature industrial chain of EPON and GPON? Who has the highest cost performance? And so on. Aside from the current industrial development environment, no matter from the technical point of view, no matter which PON technology is revolutionary, it can bring huge changes to the development of broadband networks. In fact, in addition to E/GPON, there are still many technical genres of PON, such as WDM-PON, which is considered to be the future evolution technology.

WDM wavelength division multiplexing is not a new term for communication practitioners. It used to appear on transmission networks, multiple lasers are used to send multiple lasers of different wavelengths at the same time on a single optical fiber. Each signal passes through data (text, voice, video, etc) after modulation, all are transmitted in its own band. WDM can greatly increase the carrier's optical fiber infrastructure capacity. This advantage is now applied to the PON network, so there is a WDM-PON.

From the technical principle, the existing E/GPON multiplexing method is the power division type, and the WDM-PON is the division multiplexing. In the first case, the sub-channel is adopted by the star coupler, And the uplink/downlink transmission adopts the TDMA/TDM mode to achieve shared channel bandwidth. The sub-channel allocates the signal from the OLT to each ONU through power distribution; while WDM-PON is the application of Wavelength Division Multiplexing Technology in PON, optical splitter by identifying the various wavelengths of OLT, the signal is allocated to each ONU.

E/GPON is now widely used in Europe, America, and other developed countries, meeting the practical needs of broadband access networks. However, from a technical perspective, there are still many problems to solve, such as fast bit synchronization, dynamic bandwidth allocation, Baseline Drift, ONU ranging and delay compensation, and the design of the burst mode optical transceiver module. WDM-PON uses wavelength division multiplexing technology to realize upstream and downstream broadband access network, which can provide higher bandwidth and realize symmetric broadband access network, at the same time, it also avoids many E/GPON problems, and according to the plan, it has obvious advantages in network management and system upgrade.

Although WDM-PON is dominant in technical performance, it is also a relatively advanced technology. First, because the concept of wavelength division was introduced to the broadband access network for the first time, it is a revolutionary innovation compared with the traditional PON, so the progress of standard formation is relatively slow. Second, due to the inconsistent and imperfect standards, chip manufacturers, system manufacturers, and device manufacturers in the industrial chain have great differences. At present, they do not have the basis for coordination and cooperation. Second, from the current situation, even if the standard is unified, the industry chain reached a consensus, but because of the high cost of WDM-PON, some technical difficulties have not been resolved, so the cost is not high. At the same time because of its own various reasons, coupled with the current E/GPON has just begun to scale the application, so the WDM-PON can only stay in the blueprint for technological development.

Although it is far away from industrialization and large-scale application, as an innovative broadband access network technology, WDM-PON can even be comparable to LTE in the wireless broadband access network field, it has strong technical advantages and deserves further research and exploration. With the advancement of technology, the cost of wavelength division multiplexing optical devices, especially passive optical devices, is greatly reduced, and WDM devices with high quality and low price are constantly emerging, WDM-PON technology will become a foreseeable development trend of PON broadband access network.