Comparative Analyses of Dense Wavelength Division Multiplexing and Coarse Wavelength Division Multiplexing in Long-Haul Optical Data Transmission

Abstract

Although optical fiber communication is best known for transmitting information at a high rate, there is a growing demand to push the data rate even higher. To increase the overall data rate without increasing the number of fibers, Wavelength Division Multiplexing (WDM) is used. The two types of WDM technologies mainly used to transmit information at a very fast and high speed are Dense Wavelength Division Multiplexing (DWDM) and Coarse Wavelength Division Multiplexing (CWDM). In this research, we simulated both DWDM and CWDM systems with a payload of 10 Gb/s over 2, 4, 10, and 16 channels at distances of 5 km, 20 km, 50 km, and 100 km. Further on, a practical implementation of DWDM and CWDM systems with a payload of 10 Gb/s over 2, 4, 10, and 16 channels at distances of 1 km, 2 km, 3 km, 4 km, and 5 km was conducted. Both DWDM and CWDM systems were compared using the quality factor (QF), eye-opening factor (EOF), optical signal-to-noise ratio (OSNR), and received optical power (ROP). Both simulation results and practical results revealed that CWDM had a relatively better performance than DWDM. The results also showed that the quality and integrity of the signal decreased with increasing distances and increasing number of channels.