4G means fourth generation of broadband technology, succeeding 3G. It has, however, been debated whether first-release versions should be considered 4G, as discussed in the technical understanding section below. IP telephony, gaming services, high-definition mobile TV, video conferenc.
The first-release Long Term Evolution (LTE) standard was commercially deployed in Oslo, Norway, and Stockholm, it has since been deployed throughout most parts of the world.A 4G system must provide capabilities defined by ITU in IMT Advanced. Potential and current applications include amended mobile web access,
Technical understandings
In March 2008, the International Telecommunications Union-Radio communications sector was specified a set of requirements for 4G standards, named the International Mobile Advanced specification, setting peak requirements for 4G service at 100 megabits per second for high mobility communication and 1 gigabit per second for low mobility communication
.[1]
Since the first-release versions of Mobile WiMAX and LTE support much less than 1 Gbit/s peak bit rate, they are not fully IMT-Advanced compliant, but are often branded 4G by service providers. According to operators, a generation of the refers to the deployment of a new non- technology. On December 6, 2010, ITU-R recognized that these two technologies, as well as other beyond-3G technologies that do not fulfill the IMT-Advanced requirements, could nevertheless be considered "4G", provided they represent forerunners to IMT-Advanced compliant versions and "a substantial level of improvement in performance and capabilities with respect to the initial third generation systems now deployed".
[2]
Mobile WiMAX Release 2 (also known as WirelessMAN-Advanced or 802.16m') and LTE Advanced (LTE-A) are IMT-Advanced compliant backwards compatible of the above two systems, standardized during the spring 2011,[citation needed] and promising speeds in the order of 1 Gbit/s. Services were expected in 2013.[needs update]
As opposed to earlier generations, a 4G system does not support traditional circuit-switched telephony service, but all-Internet Protocol (IP) based communication such as IP telephony. As seen below, the spread spectrum radio technology used in 3G systems is abandoned in all 4G candidate systems and replaced by OFDMA multi-carrier transmission and other frequency-domain equalization (FDE) schemes, making it possible to transfer very high bit rates despite extensive multi-path radio propagation (echoes). The peak bit rate is further improved by smart antenna arrays for multiple-input multiple-output (MIMO) communications.
The first-release Long Term Evolution (LTE) standard was commercially deployed in Oslo, Norway, and Stockholm, it has since been deployed throughout most parts of the world.A 4G system must provide capabilities defined by ITU in IMT Advanced. Potential and current applications include amended mobile web access,
Technical understandings
In March 2008, the International Telecommunications Union-Radio communications sector was specified a set of requirements for 4G standards, named the International Mobile Advanced specification, setting peak requirements for 4G service at 100 megabits per second for high mobility communication and 1 gigabit per second for low mobility communication
.[1]
Since the first-release versions of Mobile WiMAX and LTE support much less than 1 Gbit/s peak bit rate, they are not fully IMT-Advanced compliant, but are often branded 4G by service providers. According to operators, a generation of the refers to the deployment of a new non- technology. On December 6, 2010, ITU-R recognized that these two technologies, as well as other beyond-3G technologies that do not fulfill the IMT-Advanced requirements, could nevertheless be considered "4G", provided they represent forerunners to IMT-Advanced compliant versions and "a substantial level of improvement in performance and capabilities with respect to the initial third generation systems now deployed".
[2]
Mobile WiMAX Release 2 (also known as WirelessMAN-Advanced or 802.16m') and LTE Advanced (LTE-A) are IMT-Advanced compliant backwards compatible of the above two systems, standardized during the spring 2011,[citation needed] and promising speeds in the order of 1 Gbit/s. Services were expected in 2013.[needs update]
As opposed to earlier generations, a 4G system does not support traditional circuit-switched telephony service, but all-Internet Protocol (IP) based communication such as IP telephony. As seen below, the spread spectrum radio technology used in 3G systems is abandoned in all 4G candidate systems and replaced by OFDMA multi-carrier transmission and other frequency-domain equalization (FDE) schemes, making it possible to transfer very high bit rates despite extensive multi-path radio propagation (echoes). The peak bit rate is further improved by smart antenna arrays for multiple-input multiple-output (MIMO) communications.
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