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5G (5th generation mobile networks or 5th generation wireless systems) denotes the next major phase of mobile telecommunications standards beyond the current 4G/IMT-Advanced standards. 5G has speeds beyond what the current 4G can offer. The Next Generation Mobile Networks Alliance defines the following requirements for 5G networks: *Data rates of several tens of megabits per second should be supported for tens of thousands of users *1 gigabit per second to be offered simultaneously to many workers on the same office floor *Several hundreds of thousands of simultaneous connections to be supported for massive sensor deployments *Spectral efficiency should be significantly enhanced compared to 4G *Coverage should be improved *Signalling efficiency should be enhanced *Latency should be reduced significantly compared to LTE〔http://www.techrepublic.com/article/does-the-world-really-need-5g〕 The Next Generation Mobile Networks Alliance feels that 5G should be rolled out by 2020 to meet business and consumer demands.〔https://www.ngmn.org/uploads/media/NGMN_5G_White_Paper_V1_0.pdf〕 In addition to providing simply faster speeds, they predict that 5G networks also will need to meet the needs of new use cases, such as the Internet of Things as well as broadcast-like services and lifeline communication in times of natural disaster. Although updated standards that define capabilities beyond those defined in the current 4G standards are under consideration, those new capabilities are still being grouped under the current ITU-T 4G standards. ==Background== A new mobile generation has appeared approximately every 10 years since the first 1G system, Nordic Mobile Telephone, was introduced in 1982. The first '2G' system was commercially deployed in 1992, and the first 3G system appeared in 2001. 4G systems fully compliant with IMT Advanced were first standardized in 2012. The development of the 2G (GSM) and 3G (IMT-2000 and UMTS) standards took about 10 years from the official start of the R&D projects, and development of 4G systems began in 2001 or 2002. Predecessor technologies have been present on the market a few years before the new mobile generation, for example the pre-3G system CdmaOne/IS95 in the US in 1995, and the pre-4G systems Mobile WiMAX in South-Korea 2006, and first release-LTE in Scandinavia 2009. In April 2008, NASA partnered with Machine-to-Machine Intelligence (M2Mi) Corp to develop 5G communication technology〔 Mobile generations typically refer to non–backward-compatible cellular standards following requirements stated by ITU-R, such as IMT-2000 for 3G and IMT-Advanced for 4G. In parallel with the development of the ITU-R mobile generations, IEEE and other standardization bodies also develop wireless communication technologies, often for higher data rates and higher frequencies but shorter transmission ranges. The first gigabit IEEE standard was IEEE 802.11ac, commercially available since 2013, soon to be followed by the multigigabit standard WiGig or IEEE 802.11ad. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「5G」の詳細全文を読む スポンサード リンク
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