There has been much
market positioning by manufacturers and operators around which radio
access technology is which generation. While there is general consensus
that analog systems are first generation, and TDMA systems are second
generation, it becomes much less clear what constitutes third generation
or beyond.
Over the last
25 years, ITU has developed the IMT framework of standards � or
International Mobile Telecommunication system � for mobile telephony and
continues to lead international efforts involving governments and
industry players to produce the next generation standards for global
mobile communications. Specifications for the next step in mobile
broadband wireless technology � IMT-Advanced � were agreed by the ITU
Radiocommunication Assembly in January 2012. With the completion of an
intensive programme developed by ITU�s Radiocommunication Sector (ITU-R)
to stimulate global development of the future IMT technologies and
following a detailed evaluation against stringent technical and
operational criteria, ITU has determined that "LTE-Advanced" and "WirelessMAN-Advanced"
should be accorded the official designation of IMT-Advanced. IMT-Advanced
systems include new capabilities that go beyond IMT-2000, widely
deployed since 2000 and referred to as 3G mobile technology. While the
term �4G� remains undefined, ITU has now specified the standards for IMT-Advanced,
the next step in global wireless broadband communications. IMT-Advanced
provides comprehensive support for broadband wireless data and brings
major improvements. These include increased spectrum efficiency to
handle more users at higher data rates per radio channel; a fully
packet-based architecture for reduced costs; lower latency leading to
more responsive Internet and multimedia applications; improved radio
resource management and control to enhance quality of service, and new
capabilities for the radio interface such as wideband radio channels and
multiple-input and multiple-output (MIMO) for the use of multiple
antennas at both the transmitter and receiver end to improve
communication performance.
See also:
Announcement following the approval of IMT-Advanced specifications at RA-12. |