3G-Technology

The International Telecommunication Union (ITU) defined the third generation (3G) of mobile telephony standards – IMT-2000 – to facilitate growth, increase bandwidth, and support more diverse applications. The third generation, as the name suggests, follows two earlier generations.

• The first generation (1G) began in the early 80's with commercial deployment of Advanced Mobile Phone Service (AMPS) cellular networks.
• The second generation (2G) emerged in the 90's when mobile operators deployed two competing digital voice standards. In North America, some operators adopted IS-95, which used Code Division Multiple Access (CDMA) to multiplex up to 64 calls per channel in the 800 MHz band.

3G NETWORK:
To provide standards for the 3G technology, 3GPP or Third Generation Partnership Project was established. Network providers that plan to cater to 3G mobile phones will then have to change their systems. Network providers can update their existing 2G systems to use 3G technology by incorporating GPRS services. GPRS or General Packet Radio Service can be the first step when upgrading into 3G technology. Network operators and providers who are already using GPRS can switch directly into 3G technology by going for a UMTS system.The 3G Standard
3G stands for third-generation wireless technology and networks. 3G is based on the International Telecommunication Union (ITU) initiative for a single global wireless standard called International Mobile Telecommunications-2000 (IMT-2000). This concept of a single standard evolved into a family of five 3G wireless standards. Of those five, the most widely accepted are CDMA2000, WCDMA(UMTS) and TD-SCDMA.

According to the ITU and IMT-2000, a wireless standard must meet minimum bit-rate requirements to be considered 3G:
• 2 Mbps in fixed or in-building environments
• 384 Kbps in pedestrian or urban environments
• 144 Kbps in wide area mobile environments
• Variable data rates in large geographic area systems (satellite)



In addition to providing faster bit rates and greater capacity over previous-generation technologies, 3G
standards excel by effectively:
• Delivering mobile data
• Offering greater network capacity