Historical Background of Mobile and Cellular Services

Prior to the availability of analog cellular car telephones in 1984, users who wanted to place telephone calls from their cars used mobile telephones. The first mobile telephone system was started in 1946 in St. Louis, Missouri. Costs for car telephones were high, between $2,000–$2500, and capacity was limited. The local telephone company in each city operated one transmitter and receiver for the entire area. Thus, the entire area covered by the one transmitter shared the same channels. This meant that only a limited number (25 to 35) of simultaneous calls could be placed on each city's mobile system. In addition to limited capacity, the quality of service was spotty with considerable static and breaking up of calls.

Specialized mobile radio service was more widespread than mobile telephone service prior to the mid-1980s. Mobile radio is a "closed" service. Mobile radio operators can call each other. They cannot, however, make calls to the public network or to users on other radio networks outside of their own system. Calls are made to other people on the same mobile radio system. For example, users on one taxicab service's system cannot call users on another cab's system. Police departments were early pioneers of car radios. The Detroit police department used specialized mobile radio in 1921. In the 1930s, mobile radio use spread to other public safety agencies such as fire departments. Mobile radio systems are now used for aviation, trucking, taxis and marine applications.