Wdm Technology
1.0 Wavelength-division Multiplexing Technology
1.1 Wavelength-division Multiplexing
In fibre optic telecommunications, wavelength-division multiplexing (WDM) is a technology which multiplexes multiple optical carrier signals on a single optical fibre by using different wavelengths (colors) of laser light to carry different signals. This allows for a multiplication in capacity, in addition to making it possible to perform bidirectional communications over one strand of fiber. (Tomlinson & Lin, 2000, p.345-347)
1.2 Systems involve in Wavelength-division Multiplexing technology
A WDM system uses a multiplexer at the transmitter to join the signals together and a demultiplexer at the receiver to split them apart. With the right type of fiber it is possible to have a device that does both simultaneously, and can function as an optical add-drop multiplexer. The optical filtering devices used in the modems are usually etalons, stable solid-state single-frequency Fabry-Perot interferometers in the form of thin-film-coated optical glass. Figure1.1 shows the structure of a WDM system
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Figure 1.1 Wavelength-division Multiplexing System (Tomlinson & Lin, 2000, p.349)
The concept was first published in 1970, and by 1978 WDM systems were being realized in the laboratory. The first WDM systems only combined two signals. Modern systems can handle up to 160 signals and can thus expand a basic 10 Gbit/s fibre system to a theoretical total capacity of over 1.6 Tbit/s over a single fibre pair. (Ishio et al, 2004, p.448-463)
1.3 Benefits of Wavelength-division Multiplexing technology
WDM offers an attractive solution to increasing LAN bandwidth without disturbing the existing embedded fiber, which populates most buildings and campuses, and continue to be the cable of choice for the near future. By multiplexing several relatively coarsely spaced wavelengths over a single, installed multimode network, the aggregate bandwidth can be increased by the
1.1 Wavelength-division Multiplexing
In fibre optic telecommunications, wavelength-division multiplexing (WDM) is a technology which multiplexes multiple optical carrier signals on a single optical fibre by using different wavelengths (colors) of laser light to carry different signals. This allows for a multiplication in capacity, in addition to making it possible to perform bidirectional communications over one strand of fiber. (Tomlinson & Lin, 2000, p.345-347)
1.2 Systems involve in Wavelength-division Multiplexing technology
A WDM system uses a multiplexer at the transmitter to join the signals together and a demultiplexer at the receiver to split them apart. With the right type of fiber it is possible to have a device that does both simultaneously, and can function as an optical add-drop multiplexer. The optical filtering devices used in the modems are usually etalons, stable solid-state single-frequency Fabry-Perot interferometers in the form of thin-film-coated optical glass. Figure1.1 shows the structure of a WDM system
1
Figure 1.1 Wavelength-division Multiplexing System (Tomlinson & Lin, 2000, p.349)
The concept was first published in 1970, and by 1978 WDM systems were being realized in the laboratory. The first WDM systems only combined two signals. Modern systems can handle up to 160 signals and can thus expand a basic 10 Gbit/s fibre system to a theoretical total capacity of over 1.6 Tbit/s over a single fibre pair. (Ishio et al, 2004, p.448-463)
1.3 Benefits of Wavelength-division Multiplexing technology
WDM offers an attractive solution to increasing LAN bandwidth without disturbing the existing embedded fiber, which populates most buildings and campuses, and continue to be the cable of choice for the near future. By multiplexing several relatively coarsely spaced wavelengths over a single, installed multimode network, the aggregate bandwidth can be increased by the