An intermediate optical terminal, or optical add-drop multiplexer (OADM). This is a remote amplification site that amplifies the multi-wavelength signal that may have traversed up to 140 km or more before reaching the remote site.OverviewIn, wavelength-division multiplexing (WDM) is a technology which a number of signals onto a single by using different (i.e., colors) of. A WDM system uses a at the to join the several signals together and a at the to split them apart. With the right type of fiber, it is possible to have a device that does both s. Originally, the term coarse wavelength-division multiplexing (CWDM) was fairly generic and described a number of different channel configurations. In general, the choice of channel spacings and frequency in these co.