Huawei is the most powerful mobile phone, is the core network and base station!

Base station development

At the beginning, RRU was still hanging on the wall of the computer room, and the BBU was installed in a standard cabinet, and between the RRU and the antenna still passed the feeder (7/8 feed).
Continue to develop, RRU begins between the tower, BBU and RRUs through the optical fiber connection, RRU and antennas, from which the RRU is connected, and the RRU needs to be taken with the tower.

After entering 4G, the traditional macro base station has been completely replaced by the BBU + RRU + antenna mode, and some BBUs are unified in one machine room, which make up the BBU pool.

5G era, the structure of the base station has undergone new changes, and new equipment AAU has appeared.
5g The AAU appeared, in fact, because 5G introduced MASSIVE MIMO technology.
Massive MIMO, large-scale multi-bearing.

MIMO is more technically, this is actually a good understanding, you can imagine as a road, if you let the road to run more car on the road, you need more lanes, it is obviously the traffic volume of the eight lanes than the four lanes. It is much much more.

The higher the MIMO, there is more and more antennas, more and more antennas, the feeder is more and more, the more feeder interfaces on the RRU, and this process is more and more . The additional feeder itself has a certain drop, which will also affect some system performance.
It is also because of this reason, in 5G, the RRU and the original passive antenna set are integrated, and the latest AAU (active antenna processing unit) is formed.

Integrated antenna, so the volume and weight of AAU is greater than RRU, and power consumption has more large increase, and the price is much more expensive.