Optical Network Design and Implementation

Wavelength-Division Multiplexing

Wavelength-division multiplexing (WDM) is the process of multiplexing wavelengths of different frequencies onto a single fiber. This operation creates many virtual fibers, each capable of carrying a different signal. Figure 4-1 shows a schematic of a bidirectional WDM system. This system has n service interfaces and n wavelengths transmitted in either direction over a single fiber. Each wavelength operates at a different frequency.

Figure 4-1. WDM Schematic

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WDM uses wavelengths to transmit data parallel-by-bit or serial-by-character, which increases the capacity of the fiber by assigning incoming ...