Introduction to DWDM Technology

DWDM - Dense Wavelength Division Multiplexing

WDM technology is a fiber communication technology transmitting multiple optical carriers with information (analog or digital) on one fiber.

WDM concept was first published in 1978, and by 1980 WDM systems were being realized in the laboratory. The first WDM systems combined only two signals. Modern systems can handle 160 signals and can thus expand a basic 200,100,10 Gbit/s across the metro, regional, long-haul, and ultra-long-haul DWDM system over a single fiber pair to over 16 Tbit/s. A system of 320 channels in also present (12.5 GHz channel spacing). 400G DWDM Prototype for Next Generation Ultra-Broadband Transmission possible also.

Compared to 100-Gbps CP-QPSK, CP-16QAM modulation doubles the spectral efficiency, transmitting 200 Gbps per wavelength at the same baud rate while reducing unregenerated reach up to 10000 KM. 

Dense wavelength division multiplexing Concept:

DWDM Basic System: