While WDM offers many advantages, it also has some drawbacks: Signal Separation: Signals must be sufficiently spaced apart in frequency to avoid interference. Limited to Point-to-Point Circuits: Light waves carrying WDM signals are typically restricted to two-point connections. Scalability. WDM systems are divided into three different wavelength patterns: normal (WDM), coarse (CWDM) and dense (DWDM). This simplicity allows for up to 18 channels across a wide spectral grid from 1271nm to 1611nm. In contrast. Wavelength Division Multiplexing (WDM) allows multiple data streams to be transmitted simultaneously over a single optical fiber. As two modern WDM technologies, they are both used for increasing the. However, the review study presented in this paper deals with the CWDM technique as the best choice in decreasing capital expenditure after taking into consideration the simplicity of design, the capability of expanded transmission, low cost of components and reduction in operational cost.
