Base stations are part of a mobile radio network that represents the **largest part of the overall mobile network**. A fixed station that uses **radio waves** to communicate with mobile devices. It serves as **the link** between the user’s device and the carrier’s network. Base stations range in size and area of coverage. Some may cover a radius of several kilometers while others cover only a few city blocks. Most stations transmit in all directions but there are also directional antennas aimed at a specific direction. Usually base stations are owned by a single carrier but may offer roaming coverage for other networks. **Node B** — radio base station for 3G UTMS networks (Universal Mobile Telecommunications Service) **eNodeB** — radio base station for 4G LTE (Long Term Evolution) networks **gNodeB** — radio base station for 5G NR (New Radio) networks eNB = Evolved Node Base Station ![[Pasted image 20230214001108.png]] eNodeB represents the 4G LTE radio access network E-UTRAN — Evolved UMTS Terrestrial Radio Access Network. It connects to the 4G LTE core network, the EPC — Evolved Packet Core. ----- ### Base Station Components: - Power Amplifier (PA) - most energy consuming - Main Supply - DC-DC converter - Radio Frequency (RF) - Baseband Unit (BBU) - Cooling System --- #### Radio Network A mobile network consists of: - radio network (largest part of it and consists of cell towers/base stations) - core network The radio network connects to the mobile core network which is like a telephone exchange or central office.  The [core network](https://commsbrief.com/what-is-a-mobile-core-network/) connects the mobile users to external networks to make calls or to access the internet. ![[Pasted image 20230214001439.png]]