1.1 Generation Zero

The study of the history of cellular systems can help us understand the need for the system design concepts we have today. One of the major developments in WWII was the miniaturization of FM radio components to a backpack or handheld device (the walkie-talkie), a half-duplex (either transmit or receive, not both) push-to-talk communication device. After returning from war, veterans had the expec-tation that wireless communications should be available in their civilian jobs [4]. But the phone system, the Public Switched Telephone Network (PSTN) was: wired, and manually switched at telephone exchanges. In 1952, the Mobile Telephone System (MTS) was designed to serve 25 cities in the US [3] (including one in Salt Lake City [2]). In each city, an ad-ditional telephone exchange office was created for purpose of connection with the mobile telephones [4]. The MTS and later the improved mo-bile telephone system (IMTS), introduced in 1964, were not particularly spectrally efficient