The history of mobile telephon systems
The history of mobile telephone systems
Mobile transmitting is used to broadcast signals or messages bidirectional between one or more broadcast- and receive antennas. One antenna is moveable and the other is fixed. And so the moveable antenna with their process unit is called Mobil station in the German speaking vernacular it is called handy.
The beginning of mobile transmitting reaches back till the year 1920.
At that time the German national railway offered a public railway telephone.
In the USA in1946 the first portable mobile device was introduced.
However we have to smile amusedly at the word "mobile" because you needed a good condition and had to be a fast speaker because the weight of the device was 18 kg and the accumulator lasted for only 8 minutes.
On the 20th June 1953 in Germany - on the occasion of the Munich traffic exhibition - the first mobile call out of a VW Beetle was done. These were the first test modes of the German
A - Net which 5 years later was opened for commercial use.
The mobile device had a weight of 16 kg and a price of DM 8000 - on the other hand you got a new VW Beetle for only DM 5000.
In Germany in 1957 the first mobile transmitting net went online - the so called A - Net.
In this case you were hand arranged by a nice receptionist and there were no routing processes like today.
If you wanted to reach a mobile participant you had to knew in which geographical mobile zone he stayed - at that time there where 137 of such zones.
Was the participant not in the expected zone so you had bad luck and could not be connected.
A radio cell had a diameter of 30 km - so if a mobile caller leaved a cell the call automatically was finished because they had no Roaming and Handover like today.
The A - Net had 850 participants and was shut down in 1977.
1972 , the year of the Olympic games in Munich , the next generation of analogy mobile transmitting was introduced - the B - Net , a technology which was also used in Austria since 1974.After all the mobile participant were now allowed to dial by there own(no Miss at the telephone exchange) and could be called directly.
However you had to know in which mobile zone the participant is. Handover between the mobile zones still did not work (unless the participant said: Attention I am going to change the zone - call me in the next zone under the number XXXXXXXX).
The mobile devices were big, heavy, expensive and needed a lot of energy so that they were preferred in cars.
Apart from that the participant capacity of the B - Net was very limited.
The German B - Net had 27.000 users at all.
In the meantime the laboratories tried to realise a cellular mobile transmitting net to offer better services (e.g. Handover - interruption free hand over of a call to another geographical zone).
In Scandinavia a mobile transmitting net in the frequency range of 450MHz was developed which was introduced in Scandinavia under the name NMT450 (Nordic Mobile Telephone System). NMT450 was able to fall back on automatically agencies which were developed in the 70ies. For Austria was the NMT450 very interesting because this technology was used for the C - Net which was introduced in 1984 and lasted till 1997.
The C - Net had a uniform area code. In Germany the C - Net was introduced in 1986 and had 800.000 participants at all.
The development did not stand still. So in Europe the NMT system was further developed for frequency of 900 MHz. This higher frequency allowed smaller mobile devices.
In Austria in 1990 the analogy D - Net was introduced which used the TASC - Standard.
So far all introduced mobile nets were analogy technologies. They are summarized called the first mobile transmitting standard.
At the beginning of the 80ies they recognized that the future of mobile transmitting will be the digital technology because the bandwidth of the analogy technology was very modest and also the participant capacity.
Therefore 1982 a group called "Groupe Spéciale Mobile" was founded, which worked for the organisation CEPT (Conference Européen des Administration des Postes et des Telecommunications) and they had to develop a new 900MHz mobile standard.
1987 the result of this development was signed by 18 states in the so called "Memorandum of Understanding".
1988 this standard was adopted by the European institute ETSI.
Also other non-European states where interested in this new standard and so the short cut GSM, which original called "Groupe Spéciale Mobile", now was interpreted as "Global System for Mobile Communication".
GSM is so called the second mobile transmitting standard.
In December 1994 in Austria the first GSM-Net went online, it was the A 1-Net from Mobilkom. Already 1996 the Mobilkom had 120.000 participants which was an unexpected success because they only expected 200.
000 in whole Austria.
Four years later, in March 2000, the Mobilkom enlarged their participant number about the factor 20 that means 2.400.000 people.
An unbelievable story of success of the GSM-Net can be recognized.
1998 in Austria the first DCS-1800 Net from Connect Austria went online.
The DCS-1800(Digital Cellular System) is a GSM Standard which works on a frequency of 1800MHz and so a smaller broadcast performance is needed.
In the year 1998 there passed also new standards which were able to transfer EDV-Data's fast. The HSDSC- and the GPRS-Standard belong to them.
HSCSD (High Speed Circuit Switched Data) is a performance based operation with 14,4kbit/s per used channel.
GPRS (General Packet Radio Service) transmits its data's package orientated with a speed of 171,2kbit/s (average will be 104kbit/s).
HSCSD was introduced in Dezember1999 from Connect Austria (at that time with 2 bundled channels and a data rate of 28.
8kbit/s), GPRS was used the first time at August 2000 from Mobilkom Austria.
As well from December 1999 it was possible to use internet services with so called WAP-Cellular phones although the services were modest and performance reduced.
On the 25th September 2002 a new mobile transmitting generation called UMTS started in Europe.
The Mobilkom Austria started the first European UMTS-Net and from the beginning they had a supply of 25%. For that in all Austrian capitals, expect Salzburg, UMTS-services were possible. At this time was a mangle of UMTS-cellulars and therefore were only 1000 "friendly users" for a UMTS-Test run.
On 25th April 2003 The Mobilkom Austria (A1) opened their UMTS-Net for commercial use
(Provided that the people got one of the rarely UMTS-cellulars).
The UMTS-Net from A1 covered 42% of the population.
Beyond the UMTS-coverage the participant automatically phone in the GSM-Net.
On 5th May 2003 the second UMTS-Net in Austria, from Hutchinson 3G (drei), went online.
Drei has a video- and data coverage of the congested areas and a base coverage all over
Austria.
With this new standard it is possible to make video calls and to have a fast data connection with 384kbit/s.
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