Wavelength division multiplexing

1. Muhammad Uzair Rasheed 2009-CPE-03 UCE&T BZU MULTAN

2. WAVELENGTH DIVISION MULTIPLEXING

3. Multiplexing Is the set of technique that allow the simultaneous transmission of multiple signals across a single data link.

4. Types of multiplexing diagram Multiplexing Analog Digital FDM WDM TDM

5. a multiplexing technique working in the wavelength domain An analog multiplexing technique to combine optical signal. Wavelength division mutliplexing

6. 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 fiber system to a theoretical total capacity of over 1.6 Tbit /s over a single fiber pair. History

7. In fiber-optic communications Wavelength –division multiplexing (WDM) is a technology which multiplexes multiple optical carrier signals on a single optical fiber by using different ( colours ) of laser light to carry different signals. WDM

8. Most WDM systems operate on single mode fiber optical cables, which have a core diameter of 9 µm. Certain forms of WDM can also be used in multi-mode fiber cables (also known as pre mises cables) which have core diameters of 50 or 62.5 µm.

9. Why Is WDM Used? With the exponential growth in communications, caused mainly by the wide acceptance of the Internet, many carriers are finding that their estimates of fiber needs have been highly underestimated. Although most cables included many spare fibers when installed, this growth has used many of them and new capacity is needed.

10. Three methods exist for expanding capacity 1)installing more cables, 2) increasing system bit rate to multiplex more signals 3) wavelength division multiplexing.

11. Type of WDM 1)CWDM 2)DWDM

12. DWDM No official or standard definition Implies more channels more closely spaced that WDM DWDM-based networks create a lower cost way to quickly respond to customers' bandwidth demands and protocol changes. A key advantage to DWDM is that it's protocol- and bit-rate independent. Dense Wavelength Division Multiplexing

13. CWDM No official or standard definition number of channals is fewer than in dense wavelength division multiplexing (DWDM) but more than in standard wavelength division multiplexing (WDM). Laser emmission Coarse wavelength division multiplexing

14. CWDM system have channel at wavelengths spaced 20 nanometers (nm). DWDM 0.4 nm spacing Energy tolerance CWDM&DWDM

15. WDM technology allows multiple connections over one fiber thus reducing fiber plant requirement. This is mainly beneficial for long-haul applications. Campus applications require a cost benefit analysis. WDM technology can also provide fiber redundancy. WDM provides a managed fiber service. Benefits of WDM