2G and 3G technologies denote the second and third generation technologies used in wireless communication. In modern world increasing demand for communication has resulted in several standards for mobile communication. Among them 2G and 3G are dominant standards which revolutionize the mobile communication industry in past few years. Both standards emphasize on various targets and as a result various technologies have been introduced.
2G (GSM) Technology
Global System for Mobile communication is also known as 2G which is the first step towards the digital wireless communication over existing analog mobile communication prevailing. Technology standard was first introduced in 1991 and from that onwards number of subscribers has grown over 200 million during 1998. In this technology for the first time SIM (Subscriber Identity Module) is introduced and a more secured and clear communication was established. This has been widely adopted all over the world and currently the most area of the globe is covered with GSM. In GSM the multiple techniques used are TDMA (Time Division Multiple Access) and FDMA (Frequency Division Multiple Access) so that many subscribers are allowed to make calls at a given time. The cell concept is also introduced here and each cell is responsible for covering a small area. Spectrum utilization for GSM falls in to several bands like GSM 900 and GSM 1800 (DCS) used in areas like Asia, Europe etc and GSM 850 and GSM 1900 used mainly in USA and Canada. The bandwidth of the channel allocated per user is 200kHz and the GSM air interface data rate is 270kbps.
3G Technology
3G is the mobile standard specification released which are compatible with the IMT (International Mobile Telecommunications-2000) specifications for multimedia supporting. Since the GSM air interface data rates are not enough to provide high quality multimedia applications through mobile phones 3G specifications are released and paved way for the next generation standard. Applications like video calls, high speed internet, multimedia applications, video streaming, video conferencing, and location based services can be given to the mobile phones. The first commercial 3G network was launched in 2001 in Japan. Here the air interface technology which is also known as the multiple access technique is a variation of CDMA (Code Division Multiple Access) called as WCDMA which utilizes a bandwidth of 5MHz offering high data rates. Also the other CDMA technologies like CDMA2000, CDMA2000 1x EV-DO are used in various places over the world. The data rates for the 3G are a minimum of 2Mbps for stationary mobile users and 384Kbps for moving subscribers in downlink.
Difference between 2G and 3G Technologies 1. 2G is the GSM specification intended for providing mobile communication for voice and 3G is the specification for mobile communication with enhanced capabilities for mobile users other than voice. 2. GSM air interface data rate is 270Kbps and 3G allows a minimum of 2Mbps downlink in stationary mobile and 384Kbps while moving. 3. GSM uses TDMA and FDMA for multiple access technology and 3G utilizes variations of CDMA technology like WCDMA, CDMA2000, CDA2000 1X EV-DO. 4. A5 ciphering algorithm is used in 2G and a more secured KASUMI encryption is used in 3G mobile communication. |
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