31.2 Evolution of Mobile Systems Before LTE
for service delivery, charging etc., gave a very clear indication of the potential for applications over
packet data in mobile systems, in spite of the fairly low data rates supported at the time.
With the advent of 3G and the higher-bandwidth radio interface of UTRA (Universal Terrestrial
Radio Access) came possibilities for a range of new services that were only hinted at with 2G and
2.5G. The 3G radio access development is today handled in 3GPP. However, the initial steps for 3G
were taken in the early 1990s, long before 3GPP was formed.
What also set the stage for 3G was the internationalization of cellular standards. GSM was a pan-
European project, but it quickly attracted worldwide interest when the GSM standard was deployed in
a number of countries outside Europe. A global standard gains in economy of scale, since the market
for products becomes larger. This has driven a much tighter international cooperation around 3G cel-
lular technologies than for the earlier generations.
1.2.1 The First 3G Standardization
Work on a third-generation mobile communication started in ITU (International Telecommunication
Union) in the 1980s, first under the label Future Public Land Mobile Telecommunications Systems
(FPLMTS), later changed to IMT-2000 [1]. The World Administrative Radio Congress WARC-92
identified 230 MHz of spectrum for IMT-2000 on a worldwide basis. Of these 230 MHz, 2 60 MHz
was identified as paired spectrum for FDD (Frequency-Division Duplex) and 35 MHz as unpaired
spectrum for TDD (Time-Division Duplex), both for terrestrial use. Some spectrum was also set aside
for satellite services. With that, the stage was set to specify IMT-2000.
In parallel with the widespread deployment and evolution of 2G mobile-communication systems
during the 1990s, substantial efforts were put into 3G research activities worldwide. In Europe, a
number of partially EU-funded projects resulted in a multiple access concept that included a Wideband
CDMA component that was input to ETSI in 1996. In Japan, the Association of Radio Industries and
Businesses (ARIB) was at the same time defining a 3G wireless communication technology based
on Wideband CDMA and also in the USA a Wideband CDMA concept called WIMS was developed
within the T1.P1
2
committee. South Korea also started work on Wideband CDMA at this time.
When the standardization activities for 3G started in ETSI in 1996, there were WCDMA concepts
proposed both from a European research project (FRAMES) and from the ARIB standardization in
Japan. The Wideband CDMA proposals from Europe and Japan were merged and came out as part
of the winning concept in early 1998 in the European work on Universal Mobile Telecommunication
Services (UMTS), which was the European name for 3G. Standardization of WCDMA continued in
parallel in several standards groups until the end of 1998, when the Third Generation Partnership
Project (3GPP) was formed by standards-developing organizations from all regions of the world.
This solved the problem of trying to maintain parallel development of aligned specifications in mul-
tiple regions. The present organizational partners of 3GPP are ARIB (Japan), CCSA (China), ETSI
(Europe), ATIS (USA), TTA (South Korea), and TTC (Japan).
At this time, when the standardization bodies were ready to put the details into the 3GPP speci-
fications, work on 3G mobile systems had already been ongoing for some time in the international
arena within the ITU-R. That work was influenced by and also provided a broader international
framework for the standardization work in 3GPP.
2
The T1.P1 committee was part of T1, which presently has joined the ATIS standardization organization.
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