A cell site, cell phone tower, cell base tower, or cellular base station is a cellular -enabled mobile device site where antennas and electronic communications equipment are placed on a raised structure (typically on a radio mast, or tower) to create a cell, or adjacent cells . A cell site, cell phone tower, cell base tower, or cellular base station is a cellular -enabled mobile device site where antennas and electronic communications equipment are placed on a raised structure (typically on a radio mast, or tower) to create a cell, or adjacent cells . Power Amplifier: The RF signals are power amplified before transmission to their destinations for increased signal strength. Therefore, this is very important for enabling the signals to cover long distances and even penetrate barriers in the communication environment. Omnidirectional antennas, typically whip or cylindrical types, transmit in all directions. These structures facilitate the transmission and reception of signals between mobile devices and the wider network, enabling voice. Tower: In order to raise the antennas to a sufficient height to gain the coverage required, the traditional approach is to use a tower, although the base stations may be located in many other places including on top of buildings. Radio Unit, RU / RRU: The radio unit is also often referred to the. Often referred to as the brain center, this includes: Baseband Unit (BBU): Handles baseband signal processing. Active Antenna Unit (AAU): Integrates RRU and antenna for 5G-era efficiency.