WDM (Wavelength Division Multiplexing) is a technique used in fiber optic communication to increase the amount of data that can be transmitted over a single optical fiber. This is achieved by transmitting multiple data streams on different wavelengths of light simultaneously.In a WDM system, the optical signals carrying data from different sources are combined onto a single fiber by using different wavelengths (colors) of light. These signals are then transmitted over long distances with minimal interference between them. At the receiving end, the signals are separated back into their original streams by using a demultiplexer.There are two main types of WDM: coarse wavelength division multiplexing (CWDM) and dense wavelength division multiplexing (DWDM). CWDM uses wider spacing between the wavelengths, typically around 20nm, which allows for up to 18 channels to be multiplexed on a single fiber. DWDM, on the other hand, uses tighter spacing between wavelengths, typically around 0.8nm, allowing for hundreds of channels to be transmitted over a single fiber.WDM technology has revolutionized the telecommunications industry by increasing the capacity and efficiency of fiber optic networks. It enables service providers to offer more bandwidth to their customers, leading to faster internet speeds and better quality of service. Additionally, WDM reduces the cost of network infrastructure by eliminating the need for additional fiber cables.Overall, WDM is a crucial technology for meeting the ever-increasing demand for high-speed data transmission in modern communication networks. Its ability to multiplex multiple data streams over a single fiber has significantly enhanced the performance and capacity of optical communication systems.
