PAM4 DWDM Optical Transceiver Module

DWDM dense wavelength division technology has experienced higher and higher modulation rates, including 1.25G NRZ, 2.5G NRZ, 10G NRZ and 25G NRZ. There are two rates of 50G PAM4 and 100G PAM4 using high-order modulation PAM4; and the current very competitive DWDM coherent modulation technology, mainly for 200G and 400G, and future 800G high-bandwidth services.

PAM4 DWDM optical transceivers can be plugged into embedded DWDM, which can be directly plugged into appropriate data center routers or switches, eliminating the need for a separate DWDM converter platform, significantly reducing costs and simplifying deployment and maintenance. Furthermore, with appropriate Dispersion Compensation Module (DCM) and EDFA amplification system, PAM4 modules can be added to the existing DWDM network for hybrid transmission.

The next-generation product forms based on PAM4 high-order modulation include: 50G (1X50G PAM4), 100G (2X50G PAM4) and 100G (1x100G PAM4).

50G (1X50G PAM4) Solution

The optical modules adopting the 50G (1X50G PAM4) solution include 50G SFP56 DWDM optical modules (C-band, 50Ghz wavelength interval). The product is packaged in SFP56, which has the same size as SFP+. It can be directly upgraded to 50G without changing the original deployment architecture. Both the optical port side and the electrical port side use 50G PAM4 modulation, and the transmitting end uses DWDM EML lasers. With the support of DCM dispersion compensation and EDFA, it can meet the short-distance transmission requirements of at least 80km. The total bandwidth of a single fiber supports 96 waves x50G=4800G, and its industrial-grade temperature product form can meet the needs of 5G fronthaul systems.

100G (2X50G PAM4) Solution

The optical module adopting 100G (2X50G PAM4) scheme has 100G QSFP28 DWDM optical module (C-band, 50Ghz wavelength interval), which is usually called 100G PAM4 QSFP28 in the industry, and its optical port is carried by two different 50G DWDM wavelengths. 100GE business. The electrical port side adopts 4X25G NRZ, while the optical port side has two solutions: CS interface and LC interface. The CS interface adopts 2 in and 2 out, a total of 4 optical fibers; the duplex LC interface scheme uses WDM multiplexing technology inside, and only 2 optical fibers can be used for transmission. With the support of DCM dispersion compensation and EDFA, it can meet the short-distance transmission requirements of at least 80km, and the total bandwidth of a single fiber supports 96 waves x 50G = 4800G.

100G (1x100G PAM4) Solution

The optical modules adopting the 100G (1x100G) solution include 100G QSFP28 DWDM optical modules (C-band, 100GHZ). This product is mainly realized by DWDM light source + silicon light modulation technology. With the support of DCM+EDFA, it can meet 80km transmission, and the total bandwidth of single fiber supports 48 waves x100G=4800G.