History of mobile phones
The history of mobile phones can be traced back to devices that are unrecognizable in today's GSM dominated world.
Early years
![](http://upload.wikimedia.org/wikipedia/commons/thumb/c/cd/Transmitting_tower_top_us.jpg/220px-Transmitting_tower_top_us.jpg)
Mobile rigs were the beginning of mobile phones, along with taxicab radios, two way radios in police cruisers, and the like. A large community of mobile radio users, known as the mobileers, popularized the technology that would eventually give way to the mobile phone. Originally, mobile phones were permanently installed in vehicles, but later versions such as the so-called "bag phones" were equipped with a cigarette lighter plug so that they could also be carried, and thus could be used as either mobile or as portable phones.
What was possibly the first real mobile phone, in the sense that it was connected to the telephone network, was tested by the Swedish police in 1946 for use in police cruisers. A half dozen calls could be made before the police car's battery ran out. Radiophones began to be publicly available in the US at the end of the 1940s[1], though the distinction between such phones and a two-way radio becomes blurry since special systems are required to "patch" into the phone network with the assistance of human operators.
In December 1947, D. H. Ring, a Bell Labs engineer, proposed hexagonal cells for mobile phones.[1] Phil Porter, also of Bell Labs, proposed that the cell towers be at the corners of the hexagons rather than the centers and have directional antennas that would transmit/receive in 3 directions (see picture at left).
Recognizable mobile phones with direct dialing have existed at least since the 1950s. In the 1954 movie Sabrina, the playboy Linus Larrabee (played by Humphrey Bogart) makes a call from the phone in the back of his limousine.
The first fully automatic mobile phone system, called MTA (Mobile Telephone system A), was developed by Ericsson and commercially released in Sweden in 1956. This was the first system that didn't require any kind of manual control, but had the disadvantage of a phone weight of 40 kg. MTB, an upgraded version with transistors (weighing "only" 9 kg), was introduced in 1965 and used dual-tone multifrequency signaling. It had 150 customers in the beginning and 600 when it shut down in 1983.
For a discussion of the history of the Mobile Radio Service (MRS), and Improved Mobile Radio Service (IMRS) prior to the cellular mobile telephone AMPS in the US, see [2] Because of the long waiting time to be issued an MRS or IMRS radio telephone in the 1960's and 1970's, "autopatch" telephone conversations became popular among amateur radio operators with the advent of FM repeaters. Because of Federal Communications Commission rules concerning the Amateur Radio Service, business conversations were prohibited from such calls.
One of the first truly successful public commercial mobile phone networks was the ARP network in Finland, launched in 1971. Posthumously, ARP is sometimes viewed as a zeroth generation (0G) cellular network, being slightly above previous proprietary and limited coverage networks.
On April 3, 1973, Motorola employee Dr. Martin Cooper placed a call to rival Joel Engel, head of research at AT&T's Bell Labs, while walking the streets of New York City talking on the first Motorola DynaTAC prototype. Motorola has a long history of making automotive radio, especially two-way radios for taxicabs and police cruisers.
In 1978 Bell Labs launched a trial of first commercial cellular network in Chicago using AMPS [3].
First Generation Cellular
The first hand held mobile phone to become commercially available was the Motorola DynaTAC 8000X, which received approval in 1983. Mobile phones began to proliferate through the 1980s with the introduction of "cellular" phones based on cellular networks with multiple base stations located relatively close to each other, and protocols for the automated "handover" between two cells when a phone moved from one cell to the other. At this time analog transmission was in use in all systems. Mobile phones were somewhat larger than current ones, and at first, all were designed for permanent installation in cars (hence the term car phone). In Switzerland, the name for the big car-based phone models was "Nationales Autotelefon", and the abbreviation of it ("Natel") persists as the common designation for mobile phones. Soon, some of these bulky units were converted for use as "transportable" phones the size of a briefcase. . Motorola introduced the first truly portable, hand held phone. These systems (NMT, AMPS, TACS, RTMI, C-Netz, and Radiocom 2000) later became known as first generation (1G) mobile phones.
In September 1981 the first cell phone network with automatic roaming was started in Saudi Arabia; it was an NMT system manufactured by Svenska Radio Aktiebolaget (SRA). One month later the Nordic countries started an NMT network with automatic roaming between countries.
Second Generation Cellular
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Patents
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See also
- ^ see external link for 1947 memo
External links
- 1947 memo by D. H. Ring proposing hexagonal cells
- The history of cellular telephones
- The Route from Analog to 3G An overview of the history of the cell phone from the first analog systems to the 3G systems now available
- Cell Phone Basics