The biggest difference in the appearance of dual-fiber and single-fiber CWDM Mux/Demux devices is that the single-fiber version has a simplex line port. However, some of them are also made with duplex ports where only one port of the duplex is available and the other port is marked N/A.

The main reason why this Mux/Demux enables bidirectional transmission is that it utilizes CWDM wavelengths differently compared to the dual fiber type. In a bidirectional CWDM network, each wavelength operates in two opposite directions, while in a unidirectional CWDM network, they operate in only one direction.

So if you want to create a bidirectional transmission link between two different sites, you can use one wavelength over duplex fiber, use dual fiber CWDM Mux/Demux, or use two wavelengths of simplex fiber over single fiber Use single fiber CWDM Mux/Demux.

How to choose a transceiver for a single fiber CWDM Mux/Demux?

Some people may be confused about how to choose a CWDM transceiver for a single fiber CWDM network because there are two different wavelengths on the duplex channel port. The transceiver selection of the single fiber CWDM multiplexer is mainly based on the wavelength of the TX. Fiber transceivers for single fiber CWDM Mux and Dmux are different at the two sites.

For example: if the Tx value is 1290nm, you should buy a 1290nm CWDM transceiver, if the Tx value is 1270nm, you should buy a 1270nm CWDM transceiver, etc. Therefore, you can easily select transceivers for single fiber type devices without any confusion.

If you are still looking for a CWDM Mux/Demux for your application, you can contact FiberWDM. We are professional manufacturer and exporter supplying cwdm mux demux. Products include 8-channel cwdm mux demux module, 16-channel cwdm mux demux and single fiber cwdm mux demux, etc. Feel free to consult.