Requirements for Optical Wavelength Division Multiplexers

The main parameters of optical WDMs include wavelength range, channel spacing, insertion loss, polarization handling, and the number of channels, which define their performance and suitability for different fiber-optic applications.Key Parameters1. Wavelength Range: This defines the spectrum over which the WDM operates. CWDM systems typically cover 1270–1610 nm with 20 nm spacing between channels, while DWDM systems operate in the C-band (1530–1565 nm) and can extend to the L-band (1565–1625 nm) for ultra-dense applications . 2. Channel Spacing: Channel spacing determines how closely wavelengths are packed. CWDM uses wide spacing (20 nm) for fewer channels and simpler transceivers, whereas DWDM uses narrow spacing (100 GHz, 50 GHz, or even 12.5 GHz) to support many channels on a single fiber . 3. Insertion Loss: Insertion loss measures the signal attenuation caused by the WDM. Lower values are preferred for minimal signal degradation. Typical insertion loss is