As a core parameter of optical modules, the market demand for ultra-long distance transmission optical modules is also rising steadily, and ultra-long distance transmission solutions have become the development trend of the future communication industry. At the same time, with the rapid development of cloud computing, big data and Ethernet, operators will upgrade the data center to a higher data rate, which further increases the demand for 100G, 100G QSFP28 ZR4 optical module came into being. This article Walsun will talk about the 100G QSFP28 ZR4 optical module.
100G ultra-long distance transmission optical modules include 100G QSFP28 ER4 and 100G QSFP28 ZR4 two optical modules, of which the farthest transmission distance of ER4 is 40KM, the farthest transmission distance of ZR4 is 80KM.
Product characteristics
100G QSFP28 ZR4 optical module small size, low power consumption, maximum power consumption of 6.5W, dual LC optical interface, using hot-swappable QSFP28 package, support 0-70℃ commercial grade operating temperature, in line with the latest SFF-8665/8636 described in the QSFP28 industry standard and related MSA, And it can use the digital diagnostic function through the I2C interface, the maximum rate can be up to 103.125Gbps (4x25G NRZ), after cost optimization, support 100G Ethernet, can achieve up to 80KM transmission, when the system opens FEC, through a pair of single-mode fiber transmission distance up to 90KM.
The following table shows the types of Walsun 100G QSFP28 optical modules:
| Prodcut | Walsun PN | Wavelength（nm） | Distance | Connector |
| QSFP28 SR4 | EQ28510X-3LCD01 | 850 | 100m | MPO |
| QSFP28 PSM4 | EQ23110X-3LCD2 | 1310 | 2km/10km | MPO |
| QSFP28 CWDM4 | EQ2xx10X-3LCD2 | CWDM4 | 2km | LC |
| QSFP28 LR4 | EQ2xx10X-3LCD10 | LAN-WDM | 10km/20km | LC |
| QSFP28 ER4 | EQ2xx10X-3LCD30 | LAN-WDM | 30km | LC |
| QSFP28 ER4 | EQ2xx10X-3LCD40 | LAN-WDM | 40km | LC |
| QSFP28 ZR4 | EQ2xx10X-3LCD80 | LAN-WDM | 80km | LC |
Transmission principle
At the transmitter end, 4-channel serial data (NRZ) is recovered by the CDR and passed to four laser drivers to control four lasers with central wavelengths of 1296nm, 1300nm, 1305nm and 1309nm. The optical signal is multiplexed to a single-mode fiber via a standard LC connector. At the receiving end, the optical signal of the four channels is amplified by SOA, and the optical signal is demultiplexed by an integrated photodemultiplexer. Each optical signal is recovered by a PIN detector and then passed to a CAU-4 compliant output driver via a transresistance amplifier and CDR.
