Remember when these were more prevalent? they are only now a rare reminder of where the Cellular Telephone started its impact on the world. MIcrowave Communications. if you have ever watched shows like Magnum, P.I., or Emergency!, or Kojak, these were used by the business elite as far back as the 1970s (if not before). they were in limousines, the cars of executives, business jets, the like.
the phones themselves were usually called 'Radio Phones' or simply 'Microwave Phones' or other colliquial names. but basically they were the original form of wireless mobile telephone, now a useless museum piece today, and while one or two microwave towers may still stand today, still flashing their avoidance beacons, most are being dismantled in favor of more newer cellular towers. used to be those microwave towers were just as common. i am unsure of when the technology became obsolete, but i think they were still in use until at least the early 1980s