In the same optical fiber at the same time to two or more optical wavelength signals through different optical channels for transmitting information, it is known as wavelength division multiplexing technology (WDM). Here we are going to show you what is wavelength division multiplexing (WDM) and main advantages of WDM.
What Is Wavelength Division Multiplexing (WDM)?
Wavelength Division Multiplexing (WDM) is generally applied to Wavelength Division Multiplexers and Demultiplexers (also known as Combiners / Demultiplexers), which are placed at both ends of optical fiber respectively to realize the coupling and separation of different light waves. The principle of these two devices is the same. The main types of optical wavelength division multiplexer are fused taper type, dielectric type, raster type and flat type. The main characteristics of indicators are insertion loss and isolation. Generally speaking, the increase of the optical link loss is called the wavelength division multiplexing insertion loss after the WDM device is used in the optical link. When the wavelength 11, l2 is transmitted through the same optical fiber and the splitter in the input terminal l2 power and 11 mixed output power of the optical fiber is called the difference between the degrees of isolation.
Optical fiber communication line can be divided into wavelength multiplexing / demultiplexing devices. According to the number of multiplexing wavelength, it can be divided into two wavelengths multiplexer and multiple wavelength multiplexer. According to the interval between multiplexing wavelengths, it can be divided into coarse wavelength division multiplexer (CWDM) and dense wavelength division multiplexer (DWDM) for use in various wavelength division multiplexing systems and optical fiber amplifiers. There are various kinds of CWDM and DWDM products in the optical communication industry, like CWDM SFP, CWDM MUX/DEMUX and DWDM MUX/DEMUX and so on.
Wavelength division multiplexing technology is widely used in current optical communication and interconnection. And there are many advantages of WDM in optical communication. Some optical wavelength division multiplexing technical features and advantages are as follows:
Main Advantages of WDM in Optical Communication
1. Make full use of the low loss band of the optical fiber to increase the transmission capacity of the optical fiber and double the physical limit of transmitting information through one optical fiber. At present, we just use a very small part of the optical loss spectrum (1310nm-1550nm). Wavelength division multiplexing can make full use of the huge bandwidth of single-mode optical fiber to about 25THz and sufficient transmission bandwidth.
2. The ability to transmit two or more unsynchronized signals in the same optical fiber facilitates the compatibility between digital signals and analog signals, and has nothing to do with the data rate and modulation mode, and can flexibly remove or join channels in the middle of the line.
3. For optical fiber cables already built, especially those with few cores laid early, as long as the original system has power headroom, it can be further compatibilized to realize the transmission of multiple one-way signals or two-way signals without using the original system Great changes, with strong flexibility.
4. As a result of a substantial reduction in the amount of optical fiber used, the construction cost is greatly reduced. Due to the small number of optical fibers, it is also quick and easy to recover when a fault occurs.
5. The sharing of active optical equipment reduces the cost of transmitting multiple signals or increasing new services.
6. The active devices in the system have been greatly reduced, thus improving the reliability of the system. At present, due to the requirements of optical transmitters, optical receivers and other equipment for optical wavelength division multiplexing of multiple carriers, the implementation of the technology has a certain degree of difficulty. Meanwhile, the application of the multi-core optical cable does not appear to be particularly scarce for the traditional broadcast and television transmission services. So the actual application of WDM is not much. However, with the development of integrated cable television service, the increasing demand for network bandwidth, the implementation of various selective services, and the consideration of the economic costs of upgrading the network, etc., the features and advantages of WDM gradually emerge in the CATV transmission system, showing a broad application prospects, and even affect the development of CATV network pattern.
The above is mainly about what is wavelength division multiplexing (WDM) and its main features and advantages for optical communication. The era of optical communication is coming and there is no doubt that the wavelength division multiplexing technology will be more widely used in the optical fiber communication and transmission in the future. Many optics manufacturers, like Gigalight, also capture this opportunity to release out a lot of WDM products for faster and easier optical fiber communication.
