Key to the 5th generation of wireless systems (5G) is the use of phased array antenna technology, where individual wireless devices will be tracked by beams transmitted/received from the base ...

For example, a 100 meter antenna observing at a wavelength of 21 centimeters (a frequency of 1420 MHz) has a beam width of 0.0025 radians or 0.14 degrees (about one third the angular size of the Moon) ...