WDM is a communication technology that combines a series of optical signals with different wavelengths that carry information into one beam and transmits them along a single optical fiber; at the receiving end, a certain method is used to separate the optical signals of different wavelengths. This technology is used in the wavelength division multiplexer.
1. What is a wavelength division multiplexer
WDM (Wavelength Division Multiplexing) combines two or more optical carrier signals of different wavelengths (carrying various information) at the transmitting end through a multiplexer (also known as a multiplexer), and The technology of transmitting in the same optical fiber coupled to the optical line; at the receiving end, the optical carrier of various wavelengths is separated by a demultiplexer (also called a demultiplexer or demultiplexer), and then the optical carrier is The receiver or switch performs further processing to restore the original signal. This technology of simultaneously transmitting two or more optical signals of different wavelengths in the same optical fiber is called optical wavelength division multiplexing.
2. The working principle of wavelength division multiplexer
The principle is to combine a series of optical signals with different wavelengths that carry information into one beam and transmit them along a single optical fiber; at the receiving end, a certain method is used to separate the optical signals of different wavelengths. This technology can transmit multiple signals on a fiber at the same time, and each signal is transmitted by light of a certain specific wavelength, which is a wavelength channel.
3. Application of Wavelength Division Multiplexer
Optical wavelength division multiplexing generally uses wavelength division multiplexer and demultiplexer (also called multiplexer/demultiplexer) to be placed at both ends of the optical fiber to realize the coupling and separation of different light waves. The principles of these two devices are the same. The main types of optical wavelength division multiplexers are fusion taper type, dielectric film type, grating type and planar type. Its main characteristic index is insertion loss and isolation.
Generally, after the wavelength division multiplexing equipment is used in the optical link, the increase in the loss of the optical link is called the insertion loss of the wavelength division multiplexing. When the wavelengths 11, 12 are transmitted through the same fiber, the difference between the power of the input end 12 in the splitter and the power mixed in the output end of the fiber 11 is called the isolation.