In 4G networks, the optical modules used to connect BBU and RRU are mainly gigabit to 10Gbit optical modules. The BBU is small and exquisite, with low power consumption, while the RRU is large and has high power consumption. Because the base station is divided into two parts to work. In order to resist harsh environments such as high temperature and low temperature, it is necessary to use industrial-grade optical modules or hardened active optical cables (HAOC). High temperature. AAU, RRU, and BBU are key components in a telecom network, particularly in modern wireless communication systems like 4G and 5G. Here's a breakdown of each: The central processing unit in a base station. Usually. Deterministic low latency to support cloud VR, industry control.