Before the devices that are now referred to as mobile phones
existed, there were some precursors. In 1908 a Professor Albert Jahnke and the
Oakland Transcontinental Aerial Telephone and Power Company claimed to have
developed a wireless telephone. They were accused of fraud and the charge was
then dropped, but they do not seem to have proceeded with production. Beginning
in 1918 the German railroad system tested wireless telephony on military trains
between Berlin and Zossen. In 1924, public trials started with telephone
connection on trains between Berlin and Hamburg. In 1925, the company
Zugtelephonie A. G. was founded to supply train telephony equipment and in 1926
telephone service in trains of the Deutsche Reichsbahn and the German mail
service on the route between Hamburg and Berlin was approved and offered to 1st
class travelers.
In 1926 the artist Karl Arnold created a visionary cartoon
about the use of mobile phones in the street, in the picture "wireless
telephony", published in the German satirical magazine Simplicissimus.
The portrayal of a utopia of mobile phone in literature dates back to the year 1931. It is found in Erich Kästner's children's book The 35th of May, or Conrad's Ride to the South Seas:
A gentleman who rode along the sidewalk in front of them, suddenly stepped off the conveyor belt, pulled a phone from his coat pocket, spoke a number into it and shouted: "Gertrude, listen, I'll be an hour late for lunch because I want to go to the laboratory. Goodbye, sweetheart!" Then he put his pocket phone away again, stepped back on the conveyor belt, started reading a book...
The Second World War made military use of radio telephony
links. Hand-held radio transceivers have been available since the 1940s. Mobile
telephones for automobiles became available from some telephone companies in
the 1940s. Early devices were bulky and consumed high power and the network
supported only a few simultaneous conversations. Modern cellular networks allow
automatic and pervasive use of mobile phones for voice and data communications.
In the United States, engineers from Bell Labs began work on
a system to allow mobile users to place and receive telephone calls from automobiles,
leading to the inauguration of mobile service on 17 June 1946 in St. Louis,
Missouri. Shortly after, AT&T offered Mobile Telephone Service. A wide
range of mostly incompatible mobile telephone services offered limited coverage
area and only a few available channels in urban areas. The introduction of
cellular technology, which allowed re-use of frequencies many times in small
adjacent areas covered by relatively low powered transmitters, made widespread
adoption of mobile telephones economically feasible.
In the USSR, Leonid Kupriyanovich, engineer from Moscow, in
1957-1961 developed and presented a number of experimental models of handheld
mobile phone. The weight of one model, presented in 1961, was only 70 g and
could fit on a palm. However in the USSR the decision at first to develop the
system of automobile "Altai" phone was made ("Nauka i
zhizn" magazine, 8, 1957 and 10, 1958, "Technika-molodezhi"
magazine, 2, 1959, "Za rulem" magazine, 12, 1957, "Yuny
technik" magazine, 7, 1957, 2, 1958 and 9, 1996, "Orlovskaya
pravda" newspaper, 12, 1961).
In 1965, Bulgarian company "Radioelektronika"
presented on Inforga-65 interrnational exhibition in Moscow the mobile
automatic phone combined with a base station. Solutions of this phone were
based on a system developed by Leonid Kupriyanovich. One base station,
connected to one telephone wire line, could serve up to 15 customers.
("Nauka i zhizn" magazine, 8, 1965).
The advances in mobile telephony can be traced in successive
generations from the early "0G" services like MTS and its successor
Improved Mobile Telephone Service, to first generation (1G) analog cellular
network, second generation (2G) digital cellular networks, third generation
(3G) broadband data services to the current state of the art, fourth generation
(4G) native-IP networks.
Motorola was the first company to produce a handheld mobile
phone. On 3 April 1973 Martin Cooper, a Motorola engineer and executive, made
the first mobile telephone call from handheld subscriber equipment in front of
reporters, placing a call to Dr. Joel S. Engel of Bell Labs. The prototype
handheld phone used by Dr. Martin Cooper weighed 1.1 kg and measured 23 cm
long, 13 cm deep and 4.45 cm wide. The prototype offered a talk time of just 30
minutes and took 10 hours to re-charge. Cooper has stated his vision for the
handheld device was inspired by Captain James T. Kirk using his Communicator on
the television show Star Trek.
John F. Mitchell, Motorola's chief of portable communication
products and Martin Cooper's boss in 1973, played a key role in advancing the
development of handheld mobile telephone equipment. Mitchell successfully
pushed Motorola to develop wireless communication products that would be small
enough to use anywhere and participated in the design of the cellular phone.
MTS
In 1947 AT&T commercialized Mobile Telephone Service.
From its start in St. Louis in 1946, AT&T then introduced Mobile Telephone
Service to one hundred towns and highway corridors by 1948. Mobile Telephone
Service was a rarity with only 5,000 customers placing about 30 000 calls each
week. Calls were set up manually by an operator and the user had to depress a
button on the handset to talk and release the button to listen. The call
subscriber equipment weighed about 36 kg.
Subscriber growth and revenue generation were hampered by
the constraints of the technology. Because only three radio channels were
available, only three customers in any given city could make mobile telephone
calls at one time. Mobile Telephone Service was expensive, costing 15 USD per
month, plus 0.30 to 0.40 USD per local call, equivalent to about 176 USD per
month and 3.50 to 4.75 per call in 2012 USD.
No comments:
Post a Comment