3G Mobile Phones: technology of the future

What is 3G?

3G stands for third generation (of mobile phones) and it enables increased data-handling rates and high speed bandwidth. Due to this technology, 3G mobile phones offer new features such as video conference calling, video streaming, video calls and enhanced web browsing capabilities. Older networks, known as 2G, were designed to carry voice but not data, so this feature of providing converged voice and data services makes 3G mobile networks unique. Specifically, 3G wireless networks support the following maximum data transfer rates:

2.05 Mbits/second to stationary devices.
384 Kbits/second for slowly moving devices, such as a handset carried by a walking user.
128 Kbits/second for fast moving devices, such as handsets in moving vehicles.

The above figures are maximum, the actual data rate depending upon the number of calls in progress.

Main characteristics of 3G services:

Always-on connectivity. 3G networks use IP connectivity, which is packet based.
Multi-media services with streaming audio and video.
Email with full-fledged attachments such as PowerPoint files.
Instant messaging with video/audio clips.
Fast downloads of large files such as faxes and PowerPoint files.
Access to corporate applications.

3G standards available:

- Three standards based on CDMA, namely CDMA2000, WCDMA, and TD-SCDMA.
- Two standards based on based on TDMA, namely, FDMA/TDMA and TDMA-SC (EDGE).

Europe, Japan, and Asia have agreed upon a 3G standard called the Universal Mobile Telecommunications System (UMTS), which is WCDMA operating at 2.1GHz. Note that UMTS and WCDMA are often used as synonyms. In the USA and other parts of Americas, WCDMA will have to use another part of the radio spectrum. Incidentally, most of the world’s wireless operators have chosen to use UMTS.

Disadvantages of 3G:

High costs (the technology and the maintenance are more expensive than the ones in 2G networks, reflecting in higher end-consumer prices)
Base stations need to be closer to each other (again more cost).
Bigger mobile phones (due to increased power consumption, batteries need to be larger, which makes the whole devices look not very appealing to consumers used to small & slim 2G terminals)