When pdcch order triggered by enodeb.. UE goes for contention based or contention free rach?
Hi, Yes , PDCCH order is triggered by ENB. ENB will send contention free preamble to UE to get UL synch. UE will do contention free RACH. But all contention free RACH is not an PDCCH trigger. EVen in handover time UE will do contention free RACH.
Its contention less Rach. And there is no msg3 involved. Rach req, RAR then RRC Reconfiguration. Message flow is little different than normal RACH.
Handover RACH will be initiated as Contention free, RNTI will be included in Mobility info. But while doing RACH What will be the RNTI value included in RAR? Will this be same as Mobility RNTI?
Why do we need only contention free RACH in LAA cells?
At handover time target ENB will give rach preamble to UE. Is it necessary that target ENB is to be sink with source ENB. How UE will do contention free rach when both or not in sink? Is their any case Contention free rach will fail?