Description

3G stands for the third generation of wireless communication technology. It refers to pending improvements in wireless data and voice communications through any of a variety of proposed standards. The immediate goal is to raise transmission speeds to 2Mbit/sec. 

Applications and deployment

In marketing 3G services, video telephony has often been used as the flag-ship killer application for 3G. A certain euphoria was created, which led to huge spectrum-licensing fees in many countries, especially in Europe, where spectrum auctions generated many billions of euros for the respective countries. Since these spectrum licensing fees were collected many years before any income could be expected from 3G business, and since enormous investments are necessary to build the 3G networks, many telecommunication operators got into great financial difficulties, which greatly delayed 3G roll-out in all countries except Japan and Korea, where such spectrum licensing fees were avoided since priority was set on national IT infrastructure development.

The first country which introduced 3G on a large commercial scale was Japan. In 2005 about 40% of subscribers use 3G networks only, and 2G is on the way out in Japan. It is expected that during 2006 the transition from 2G to 3G will be largely completed in Japan, and upgrades to the next 3.5G stage with 3 Mbit/s data rates is underway. The successful 3G introduction in Japan shows that video telephony is not a killer application for 3G networks after all. Actually, the real-life usage of video telephony on 3G networks is only a very very small fraction of all services. On the other hand, downloading of music finds very strong demand by customers. Music downloads were pioneered by KDDI with the EZchakuuta and the Chaku Uta Full services.

Next generation (3G) wireless networks are not IEEE 802.11 networks. Rather, they are networks dedicated to personal devices, including PDAs and cellular telephones.

3G standards

3G technologies are an answer to the International Telecommunications Union's IMT-2000 specification. Originally, 3G was supposed to be a single, unified, worldwide standard, but in practice, the 3G world has been split into four camps.

UMTS (W-CDMA) UMTS (Universal Mobile Telephone System), based on W-CDMA technology, is the solution generally preferred by countries that used GSM, centered in Europe. UMTS is managed by the 3GPP organization also responsible for GSM, GPRS and EDGE.

FOMA, launched by Japan's NTT DoCoMo in 2001, is generally regarded as the world's first commercial 3G service. However, while based on W-CDMA, it is not generally compatible with UMTS (although there are steps currently under way to remedy the situation).

CDMA 2000 The other significant 3G standard is CDMA2000, which is an outgrowth of the earlier 2G CDMA standard IS-95. CDMA2000's primary proponents are outside the GSM zone in the Americas, Japan and Korea. CDMA2000 is managed by 3GPP2, which is separate and independent from UMTS's 3GPP. The various types of transmission technology used in CDMA2000 include 1xRTT, CDMA2000-1xEV-DO and 1xEV-DV. CDMA 2000, has a data rates of 144 kbit/s to over 3 Mbit/s. Adopted by the International Telecommunication Union ITU Arguably the most successful introduction of CDMA-2000 3G networks is Japan's KDDI, which under the AU brand has more than 20 million 3G subscribers. Since December 2003, KDDI has upgraded the CDMA2000-1x network to CDMA2000-1xEV-DO which achieves data rates up to 2.4 Mbit/s. In 2006, AU plans to upgrade the network to above 3 Mbit/s.

TD-SCDMA A less well known standard is TD-SCDMA which is being developed in the People's Republic of China by the companies Datang and Siemens. They are predicting an operational system for 2005.Here is the TD-SCDMA official site TD-SCDMA Forum[1].Wireless 3G[2] is the portal 3G website in China. Wideband CDMA Supports speeds between 384 kbit/s and 2 Mbit/s. When this protocol is used in a WAN, the top speed is 384 kbit/s. When it is used in a LAN, the top speed is 2 Mbit/s. Also adopted by the ITU. UMTS TDD Supports speeds of up to 3 Mbit/s.