When we demand for higher bandwidth, we often choose to install new fiber. However, that is an expensive solution. Then what should we do? Now this article will give you a less expensive solution—using CWDM Mux/Demux with CWDM transceivers, which may allow you to maximize capacity and increase bandwidth on existing fiber route by multiplexing several distinct signals or protocols over a single or duplex-fiber connection. The passive optical CWDM Mux/Demux usually utilizes a thin-film filter and circulator technology. They are available in various wavelength combinations based on the entire wavelength spectrum (1270nm–1610nm in 20nm increments) defined by the ITU G.694.2 CWDM standard. Accordingly, CWDM transceivers are also available in 1270nm–1610nm (20nm spacing).

Since CWDM Mux/Demux can support 18 wavelengths include 1270, 1290, 1310, 1330, 1350, 1370, 1390, 1410, 1430, 1450, 1470, 1490, 1510, 1530, 1550, 1570, 1590 and 1610 nano-meters. Therefore, in the market, the channels of CWDM Mux/Demux varies from 2 channels to 18 channels. In this article, we may introduce these 4 channels CWDM Mux/Demux in detail. Using methods of other channel CWDM Mux/Demux can all reference 4 channels CWDM Mux/Demux.4 channels CWDM Mux/Demux is available in any four wavelengths from 1270nm–1610nm (20nm spacing). At present, CWDM Mux/Demux is available in dual fiber and single fiber two types. In the following passages, I will take 4 channels 1510-1570nm dual fiber CWDM Mux/Demux and 4 channels 1470-1590nm single fiber CWDM Mux/Demux for example to tell you how to use them in your WDM network.

4 Channels 1510-1570nm Dual Fiber CWDM Mux/Demux User Guide
To install a  4 channels 1510-1570nm dual fiber CWDM Mux/Demux in your network, you need a pairs of  4 channels 1510-1570nm dual fiber CWDM Mux/Demux. For dual fiber link  CWDM Mux/Demux, the Mux/Demux are always the same (shown in the following picture).

Just shown as the following picture. To install a  4 channels 1510-1570nm dual fiber CWDM Mux/Demux in your network, you just need a pair of 4 channels 1510-1570nm dual fiber CWDM Mux/Demux, a 1510nm SFP, 1530nm SFP, 1550nm SFP and a 1570nm SFP.

4 Channels 1470-1590nm Single Fiber CWDM Mux/Demux User Guide
To install a  4 channels 1470-1590nm single fiber CWDM Mux/Demux in your network, you also need a pairs of  4 channels single fiber CWDM Mux/Demux. But for single fiber Mux/Demux, they are not the same. If you install a  4 channels 1470-1590nm single fiber CWDM Mux/Demux on one end, you may need to install a 4 channels 1490-1610nm single fiber CWDM Mux/Demux on the other end (shown in the following picture).

Just shown as the following picture. To install a  4 channels 1470-1590nm single fiber CWDM Mux/Demux in your network, you need a 4 channels 1470-1590nm single fiber CWDM Mux/Demux and 4 channels 1490-1610nm single fiber CWDM Mux/Demux pair. And a 1470nm SFP, 1510nm SFP, 1550nm SFP and 1590nm SFP for 4 channels 1470-1590nm single fiber CWDM Mux/Demux. A 1490nm SFP, 1530nm SFP, 1570nm SFP, 1610nm SFP for  4 channels 1490-1610nm single fiber CWDM Mux/Demux.