The third generation of cellular phone standards and technology is known as 3G, upgrade of 2G. It is based on the International Telecommunication Union family of standards under the International Mobile Telecommunications programme.
3G technologies enable network operators to offer users a wider range of advanced services while achieving greater network capacity through improved spectral efficiency. Services include wide-area wireless voice telephony and broadband wireless data, all in a mobile environment. Typically, they provide service at 5-10 Megabite per second.
3G networks are wide area cellular telephone networks which evolved to incorporate high-speed internet access and video telephony. IEEE 802.11 (common home Wi-Fi) networks are short range, high-bandwidth networks primarily developed for data.
Rogers Wireless began implementing 3G HSDPA services in eastern Canada early 2007 in the form of Rogers Vision; expansion into western Canada is expected soon.
The most significant feature of 3G mobile technology is that it supports greater numbers of voice and data customers — especially in urban areas — and higher data rates at lower incremental cost than 2G.
By using the radio spectrum in bands identified, which is provided by the UTI for Third Generation IMT-2000 mobile services, it subsequently licensed to operators. 3G uses .6 MHz channel carrier width to deliver significantly higher data rates and increased capacity compared to 2G networks.
The .5 MHz channel carrier provides optimum use of radio resources for operators who have been granted large, contiguous blocks of spectrum. On the other hand, it also helps to reduce the cost to 3G networks while being capable of providing extremely high-speed data transmission to users.
It also allows the transmission of 384 kbit/s for mobile systems and 2 Mb/s for stationary systems. 3G users are expected to have greater capacity and better spectrum efficiency, which allows them to access global roaming between different 3G networks.
3G cell phones are designed to work on these networks. Most 3G phones still come with build in GSM frequency bands (850/900/1800/1900mhz) so they can be used on 2G GSM Networks in places where 3G capaiblity isn't available or upto par GSM Networks can be used for voice and data.