Wave Division Multiplexing (WDM)

Definition

WDM is a technology that multiplexes multiple optical carrier signals on a single optical fiber by using different wavelengths of laser light.

Detailed Explanation

Types of WDM

1. Coarse WDM (CWDM)

   • Fewer channels (usually 8-16)
   • Wider channel spacing
   • Lower cost implementation

2. Dense WDM (DWDM)

   • Many channels (40-80 typical)
   • Narrow channel spacing
   • Higher capacity but more expensive

Technical Aspects

• Uses different wavelengths of light
• Each channel carries independent data
• Requires optical amplifiers
• Needs precise wavelength control

Applications

• Long-distance fiber networks
• Metropolitan area networks
• Data center interconnects
• High-speed internet backbones