0G
0G refers to pre-cellphone mobile telephony technology, such as radio telephones that some had in cars before the advent of cellphones. Date back 1971
1G
1G (or 1-G) is short for first-generation wireless telephone technology, cellphones. These are the analog cellphone standards that were introduced in the 80's and continued until being replaced by 2G digital cellphones.
2G
2G (or 2-G) is short for second-generation wireless telephone technology. It cannot normally transfer data, such as email or software, other than the digital voice call itself, and other basic ancillary data such as time and date. Nevertheless, SMS messaging is also available as a form of data transmission for some standards.
3G Standards
3G technologies are an answer to the International Telecommunications Union's IMT-2000 specification. Originally, 3G was supposed to be a single, unified, worldwide standard, but in practice, the 3G world has been split into three camps.( UMTS CDMA and...... )
3G system must allow simultaneous use of speech and data services, and provide peak data rates of at least
200 kbit/s according to the IMT-2000 specification
4G
4G (or 4-G) is short for fourth-generation the successor of 3G and is a wireless access technology. It describes two different but overlapping ideas.
High-speed mobile wireless access with a very high data transmission speed, of the same order of magnitude as a local area network connection (10 Mbits/s and up). It has been used to describe wireless LAN technologies like Wi-Fi, as well as other potential successors of the current 3G mobile telephone standards.
Read further
Mobile Phone Generations
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