2G TechnologyDEFINITION• Second-generation wireless telephone technology.• Commercially launched on the GSM standard.• Fully digital 2G networks replaced analog 1G.
History• In 1990 (2G) mobile phone systems emerged.• In 1993 2G introduced SMS.• In 1998 the first downloadable content sold to mobile phones was the ring tone.• In 1999 first internet service on mobile phones was introduced by NTT DoCoMo in Japan
Features of 2G• Digital voice service• Push-to-Talk (PTT)• short message service (sms)• conference calling• caller iD• voice mail• simple data applications such as• email and Web browsing
Demerits of 2G• GPRS not supported.• Weaker digital signal.• MMS service not provided.• No secondary front-facing camera for video calling etc.• The Bluetooth only supports headsets.
2.5G Technology• second and a half generation Technology.• developed in between its predecessor, 2G, and its successor, 3G.• "2.5G" usually describes a 2G cellular system combined with General Packet Radio Services (GPRS).
Features of 2.5G• all 2G features plus:• mms (multimedia message service)• Web browsing• real-time location-based services such as directions• Basic multimedia• audio and video clips, games and images
2.75 Technology• EDGE data connectivity.• Faster than GPRS (sometimes called 2.5G)• EGPRS
Features of 2.75G• Better performance for all 2/2.5G services• double the speed of the 2.5G EDGE network
3G Technology• Launched by NTT DoCoMo in Japan on 1 October 2001.• 3rd generation mobile telecommunications.• Emtel Launched the first 3G network in Africa.• generation of standards for mobile phones and mobile telecommunication.• By June 2007, the 200 millionth 3G subscriber had been connected.
Features of 3G• support for all 2G and 2.5G features plus:• increasing bandwidth to DSL speeds, with a range of 144 Kbps to 2+ mbps1.• greater security than their 2G predecessors.• Full motion video• streaming music• 3D gaming• Faster Web browsing
Applications of 3G• Mobile TV• Video on demand• Videoconferencing• Telemedicine• Location-based services
Comparison between 2G and 3G 2G 3G• Digital voice service • support for all 2G and• Push-to-Talk (PTT) 2.5G features plus:• short message service • Full motion video (sms) • streaming music• conference calling • 3D gaming• caller iD • Faster Web browsing• voice mail• simple data applications • VOIP such as• email and Web browsing