25G Front-Haul Networks and 25G SFP28 LWDM Transceiver Modules

These days, the use of 25G optical transceivers is quite common in 5G front-haul networks. 25G WDM modules are preferred in 5G front-haul applications to save fiber resources. It is important to note that the 25G WDM modules are comparatively much costlier than other 25G transceivers; 25G SFP28 BiDi, SFP28 SR, SFP28 LR modules, etc. Here comes the role of 25G SFP28 LWDM transceivers – a robust alternative that supports multi-channel transmission through a single fiber. And more importantly, it comes at a much lower price than 25G WDM transceivers. Characteristics like flexibility, cost-effectiveness, and flexibility of the 25G SFP28 LWDM transceiver make it an ideal solution to be considered in challenging and extensive networking applications including 5G front-haul networking.

What makes 25G SFP28 LWDM Transceivers Suitable for 5G Front-Haul Networks?

Its complete compatibility with the 40/100Gbit/s standard (IEEE802.3ba) opens the door to smooth transition of 25G Ethernet network to a single-wavelength 50G network or even 100 networks in the future. The 25G SFP28 LWDM comes with 12 x O band wavelengths out of which eight are standard wavelengths and have 800Hz band interval. The remaining four wavelengths can be multiplexed by 25G SFP28 LWDM transceiver with 25G SFP28 CWDM transceiver wavelengths which are 1269.23nm, 1291.10nm 1332.41nm and 1313.73nm. The 25G LWDM module can multiplex numerous wavelengths using WDM technology onto a single pair of fiber. Thus, great savings can be anticipated in terms of cable and power.

As indicated in the exhibit above, the 25G LWDM (Light Wavelength Division Multiplexing) module adopts channels within 4nm which are narrower than the ones we find in 25G SFP28 CWDM’s. Thus, a large wavelength shift becomes inevitable. Generally speaking, the operating temperature range of the 25G LWDM transceiver is -40℃ to 85℃. Even a 1 ℃ change in the operating temperature is potent enough to produce an offset of approximately 0.1 nm. For steady transmission, the TEC or Temperature Control becomes a necessity for the 25G LWDM optical module. The incorporation of an adequately designed TEC enables the 25G LWDM optical module to provide accurate and stable data transmission in demanding networking applications. Please check the following table as it provides some useful information about the general characteristics of 25G SFP28 LWDM transceivers. .

The 25G SFP28 LWDM modules offer multiple wavelengths multiplexing capabilities just like 25G DWDM and CWDM transceivers. With this module, you can achieve multiple wavelengths multiplexing through one, single fiber. Here, it is important to mention that the 25G SFP28 LWDM modules are much cheaper than 25G CWDM/DWDM transceivers because it comes with cheaper PIN receivers. On the other hand, expensive APD receivers are used in 25G CWDM/DWDM transceivers. Moreover, 25G SFP28 LWDM transceivers come with cheaper DML lasers, unlike 25G CWDM/DWDM transceivers where expensive PIN type lasers are used. Conclusively speaking, 25G SFP28 LWDM modules are a cheaper alternative of 25G CWDM/DWDM transceivers to be used in 5G front-haul transmission.

Construction of a Network with 25G SFP28 LWDM Transceivers

25G LWDM transceivers and CWDM/DWDM modules offers similar kind of connectivity. However, a set of LWDM Mux/Demux must be incorporated when 25G SFP28 LWDM transceivers are to be used.

Following are a few guidelines that provide vital information for the construction of a network with involving 25G SFP28 LWDM transceivers.

Take eight 25G SFP28 LWDM modules and plug four in the first 25G switch and the remaining four in the second 25G switch.
Now, connect the two sets of 25G SFP28 LWDM modules with LWDM Mux and Demux employing single-mode optical fiber cables.

Complete the network by connecting the LWDM Mux and Demux through a single-mode optical fiber cable.

Conclusion:

25G SFP28 LWDM transceiver uses a single fiber to implement multi-channel transmission. Its ability to offset the high costs of 25G CWDM and DWDM transceivers makes it a viable and potent alternative for 5G front-haul networks. The 25G SFP28 LWDM transceiver offers reliable, cost-effective and stable performance even in the most demanding applications.