Answer:
Terrestrial microwave
Step-by-step explanation:
Based on the information provided it can be said that the type of transmission system being described is called a Terrestrial microwave transmission systems. This is a system used between ground-based microwave transmission antennas which produce a narrow, highly directional signal to another antenna in order to communicate information back and forth. Although very effective, it limits the communication to only the antenna's that have a line-of-sight with each other.