How TM mode switching happens at eNB?

Hi Experts.

How TM mode switching is happen at eNB and on what basis eNB change the transmission mode ™ in LTE?

It’s on the basis of RI and CQI.

You can switch between tm3 and tm2 / tm4 and tm2.

Tm4 is closed loop…how about PMI?

Which TM will be default initialy?

PMI not required for switching.

It’s for channel estimation in closed loop required.

Depends on network parameters settings.

Mostly network having tm4 4*2 closed loop.


How about SINR threshold used for switching?

SINR threshold seen for switching between higher TM modes ie tm8 to tm7 related to beam forming concept.

Switching between TM3 and TM4?