Multiple input multiple output (MIMO) technology is an integral part of 3GPP E-UTRA long term evolution (LTE). As part of MIMO, beamforming is also used in LTE.
This white paper discusses the basics of beamforming and explains the eight MIMO transmission modes in LTE Release 9.
Modern communications networks use MIMO technology to achieve high data rates. As a special MIMO technique, beamforming also permits targeted illumination of specific areas, making it possible to improve transmission to users at the far reaches of cell coverage. Like other communications standards such as WLAN and WiMAXTM,LTE also defines beamforming.
Beamforming is particularly important for the time division duplex (TDD) mode in LTE. This white paper describes the eight available MIMO transmission modes in LTE as specified in 3GPP Release 9, as well as how beamforming is used in LTE.
Source and download – http://cdn.rohde-schwarz.com/dl_downloads/dl_application/application_notes/1ma186/1MA186_0e_LTE_transmission_modes_and_beamforming.pdf