The STC-40004 from Swedish Telecom Opto's LPO Series is a 400 Gb/s QSFP112 DR4 module engineered for energy-efficient short-reach links over single-mode fiber (SMF). Designed on a Linear Pluggable Optics (LPO) architecture, it eliminates the need for a DSP inside the module, shifting signal. PAM4 (4-Level Pulse Amplitude Modulation): This is the predominant modulation technique used in 400G modules. PAM4 allows each symbol to represent two bits of information, effectively doubling the data rate compared to traditional NRZ (Non-Return-to-Zero) modulation 1. Module converts 8 channels of 50Gb/s (PAM4) electrical input data to 4 channels of parallel optical signals, each capable of. The 400G DR4 / FR4 / VR4 optical transceivers are designed for medium and long-distance transmission over single-mode fiber. Compared to SR4 modules, these solutions provide extended reach and improved network flexibility for backbone and interconnect applications. By leveraging PAM4 modulation and. One such type is 400G DR4. 400G DR4 is commonly employed for high-speed communication links within a data center at short to medium distances.
