Wavelength Division Multiplexing (WDM) is to combine a series of optical signals carrying information but with different wavelengths into a bundle and transmit them along a single fiber; at the receiving end, a method is used to separate the optical signals of different wavelengths. communication technology. In the transmission of uplink data through the passive optical network channel, the wavelength division multiplexing technology is used to realize the point-to-multipoint data transmission, and the downlink data is transmitted in the broadcast mode, and there will be no interference between different data packets transmitted.
1. Save backbone optical fiber resources, one main optical fiber is connected to multiple optical fibers through a passive optical splitter;
2. The construction cost and operation and maintenance management cost are low, and the passive optical network structure uses passive components in the transmission, which is easier to upgrade;
3. Provide high bandwidth, passive optical network can currently provide upstream and downstream symmetrical 1.25Gb/s bandwidth;
4. The service range is large, and the passive optical network is a point-to-multipoint network, which is similar to the topology of the cable TV network;
5. Flexibly allocate bandwidth, provide port-level SLA and QoS guarantee, and provide a good platform for multi-service access.
Features of wavelength division multiplexing technology
1. Make full use of the low-loss band of the optical fiber, increase the transmission capacity of the optical fiber, and double to several times the physical limit of the information transmitted by one optical fiber;
2. It has the ability to transmit 2 or several asynchronous signals in the same fiber, which is beneficial to the compatibility of digital signals and analog signals. It has nothing to do with data rate and modulation mode, and can flexibly take out or add channels in the middle of the line;
3. For the existing optical fiber system, especially the optical cable with a small number of cores laid in the early stage, as long as the original system has a power margin, the capacity can be further increased to realize the transmission of multiple one-way signals or two-way signals without the need to make large changes to the original system. change, with strong flexibility;
4. Due to the large reduction in the use of optical fibers, the construction cost is greatly reduced. Due to the small number of optical fibers, when a fault occurs, the recovery is also quick and convenient;
5. The sharing of active optical equipment reduces costs for the transmission of multiple signals or the addition of new services;
6. The active equipment in the system is greatly reduced, which improves the reliability of the system
After the integration of the three networks, the optical fiber splitter is connected to the MDU distribution box of each building through an optical fiber, and then an optical fiber is distributed and connected to the optical network terminal (ONT) of each user’s home from the MDU distribution box. After the realization of “three networks integration” fiber-to-the-home, users only need to pull a line or wireless access to complete the functions of communication, TV, Internet access and so on. It is an effective measure to solve the complex lines of telephone network, Internet and cable TV network in large communities and important places, difficult long-distance transmission and high construction cost.