narrow WDM (NWDM)

Narrow Wavelength Division Multip lexing (NWDM) is a wavelength division multiplexing (WDM) in the 1,300 nm range that typically operates with four wavelengths at a wavelength spacing of 25 nm. In contrast, coarse wavelength division multiplexing ( CWDM) operates with 18 channels and dense wavelength division multiplexing ( DWDM) operates with up to 160 wavelengths.