Milestones in development of wireless communications

The origins of mobile communications followed quickly behind the invention of radio in the late 1800s. The first applications of mobile radio were related to the navigation and safety of ships at sea. As radio concepts developed, so did it’s use as a communications tool. The major milestones in the development of wireless communications are summarized as follows:

1906 :-

Reginald Fesseden successfully transmits human voice over radio. Up until that time, radio communications consisted of transmissions of Morse Code.

1915 :-

J. A. Fleming invents the vacuum tube making it possible to build mobile radios.

1921 :-

The Detroit police department used a 2 MHz frequency in the department's first vehicular mobile radio. The system was only one way and police had to find a wireline phone to respond to radio messages.

1930s :-

Amplitude Modulation (AM) two-way mobile systems were in place in the U.S. that took advantage of newly developed mobile transmitters and utilized a "push-to-talk" or half-duplex transmission. By the end of the decade channel allocation grew from 11 to 40.

1935 :-

Invention of Frequency Modulation (FM) improved audio quality. FM eliminated the need for large AM

transmitters and resulted in radio equipment which required less power to operate. This made the use of

transmitters in vehicles more practical.

1940s :-

The Federal Communications Commission (FCC) recognized a communication service it classified as Domestic Public Land Mobile (DPLM) radio service. The first DPLM system was established in St. Louis in 1946 and it utilized the 150 MHz band. The following year, a "highway" system was developed along the New York - Boston corridor using the 35-40 MHz band.

1947 :-

D.H. Ring, working at Bell Laboratories, envisions the cellular concept.

1948 :-

Shockley, Bardeen and Brittain, at Bell Laboratories, invent the transistor which enables electronic

equipment, including the radio to be miniaturized.

1949 :-

Radio Common Carriers (RCCs) were recognized.

1949, 1958 :-

Bell Systems made broadband proposals.

1964 :-

AT&T introduces Improved Mobile Telephone System (IMTS).

1968 :-

The FCC began to address issue of new US spectrum requirements.

1969 :-

Nordic countries of Denmark, Finland, Iceland, Norway and Sweden agree to form a group to study and recommend areas of cooperation in telecommunication. This led to the standardization of telecommunications for all members of the Nordic Mobile Telephone (NMT) group, the first comprehensive international standardization group.

1973 :-

The NMT group specifies a feature allowing mobile telephones to be located within and across networks. This feature would become the basis for roaming.

1979 :-

The FCC authorized the installation and testing of the first developmental cellular system in the US (Illinois Bell Telephone Company).

1981 :-

Ericsson launches the world's first cellular system in Saudi Arabia based on the analog NMT 450 standard.

1991 :-

The first digital cellular standard (GSM) is launched.

1998 :-

The number of mobile subscribers world-wide has grown to over 200 million.