Recently, the International Telecommunication Union (ITU), received a six 4G (IMT-Advanced) candidates for technical proposals, this proposal is in response to ITU 2008 骞?3 month by collecting invitation.
Recently, the International Telecommunication Union (ITU), received a six 4G (IMT-Advanced) candidates for technical proposals, this proposal is in response to ITU 2008 骞?3 month by collecting invitation. 6 proposals around the 3GPP LTE version 10, LTE-Advanced Technology and IEEE 802.16m technologies ITU-R according to the needs assessment process using the defined assessment. The coming year, the evaluation will be rigorous in the world of an independent external evaluation of the working group support, and the 5D in the ITU-R Working Group under the guidance of the work. Selected technology is expected in October 2010 will be recognized as officially designated 4G technology.
Shanghai Research Center for Wireless Communications R & D a minister HU Hong-lin
Shanghai Research Center for Wireless Communications R & D a minister HU Hong-lin pointed out that for the 4G network, need to focus on key technology testing and validation, relay technology, distributed networking technology and spectrum sharing technology research and development. The key technology of 4G in 2008, China began to implement a "next-generation broadband wireless mobile communications network," major projects are reflected.
Currently, 4G major focus on alternative technologies to the 3GPP's LTE-Advanced and IEEE's 802.16m, LTE system They are the evolution of version and 802.16e (ie WiMAX) Evolution versions; both emphasize the importance of the latter with the 3G version backward compatible to support FDD and TDD duplex modes, and some recognized empty enhancement technology. Plan completed by the end of 2010 3GPP LTE-Advanced standard-setting, and IEEE 802.16m project completion time is the end of 2009. Taking into account the LTE is the world's most successful and most of the mainstream is the only operator selected potential 4G technology, LTE-Advanced, as the evolution of LTE version will no doubt be the most mainstream of the world's next generation mobile communication systems.
For 4G TDD standard, Datang Mobile president Xie Yongbin has written that: we believe that evolution should consider the following principles: TD-SCDMA to consider backward compatibility, so that a smooth evolution of TD Industries; demand for 4G NGMN and relative LTE, functional / performance have improved significantly; for TDD features independent wireless interface optimized, TDD / FDD unified network architecture and high-level; 4G TDD system to meet the needs of independent large-scale network, but can also provide data covering hot spots; consider TD -SCDMA Evolution and greater space for extensive international cooperation; in the global promotion of TD-SCDMA and the evolution of version; from the market point of view the possibility of the evolution of line (4GLTE +); 3GPP camp, the global mobile communications market now accounts for 86% share. 3GPP camp in 2010 (including the TD-SCDMA) market share will reach 88%.
Compared to 3G (IMT-2000), 4G system is more stressed around the world highly versatile, multi-capacity wireless access systems interoperability and the flexible range of services and applications support. ITU-R has previously adopted a set of minimum requirements on the 4G, including the district average, and the boundary spectrum efficiency, VoIP capacity, spectral efficiency and peak bandwidth requirements, the control plane and user plane latency and mobility requirements. Meanwhile, the World Radiocommunication Conference in 2007 decide the international standard 3G and 4G mobile communication frequency bands can be general, and to identify new, including 3.5GHz, 2.3GHz, 700MHz and 450MHz of available spectrum.
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