8.5 Historical Perspective
It is interesting to know that the concept of cellular phones is rooted in military communications. One can argue that the first experimentation of using radio telephony can be accredited to Reginald Fessenden's ship-to-shore demonstration in 1906. World War II should be credited with giving birth to the cellular phone since during the war, radio telephony links were used on a very large scale. Radio telephones were also manually linked to the wired telephone network. By the late 1940s, automobile phones were available in the USA, although they were very bulky and consumed a lot of power. These radio networks were able to support a few calls at a time. In 1946, the St Louis mobile telephone service (MTS) system could only carry three parallel calls. It was not until 1964 that a system called improved mobile telephone service (IMTS) was introduced, which could carry more voice channels and link automatically to the public telephone network. Nevertheless, public demand for these vehicle-mounted phones continued to surpass the available channels.
Prior to the availability of the automobile phones, in the 1930s, telephone customers in the USA could place a call to a passenger on a liner in the Atlantic Ocean that modulates in the VHF band. The air time rate for these calls was very high: $7 per minute in the 1930s is equivalent to about $100 per minute in 2012. Even today, in areas where marine VHF radios are available, an operator can be reached from the ...
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