Mobile radio telephone

Common card · No. 476796

Mobile radio telephones or radiophones (sometimes retroactively referred to as pre-cellular or zero generation, that is, 0G) were early forms of mobile telephony systems that preceded modern cellular networks and phones. These networks consisted of a single high-power radio tower geographically covering a city or wider open region, with the tower itself connected to the global telephone network (i.e. PSTN). The phones on the user-end were overwhelmingly car phones but portable briefcase phones also existed. The first such networks were launched in 1946 by Bell System using Western Electric and Motorola equipment. The earliest commercial telephone systems like the American Mobile Telephone Service (MTS) and German A-Netz used push-to-talk (PTT) means. As radio technology improved, later systems from the 1960s like Improved Mobile Telephone Service (IMTS) were full duplex, meaning the radio would seamlessly send and receive data at the same time. Mobile radio telephones were made redundant...

Read on Wikipedia · Image sv1ambo, CC BY 2.0