LTE DCI (Downlink Control Information) concept in detail

[@shreyasrai]

How does UE decide which DCI format to use ? Does all DCI format come in the PDCCH?

[@techLteworld]

The UE determines which DCI format to use based on the control information received on the PDCCH, identified using its RNTI and decoded according to its configuration and the DCI payload. All DCI formats are transmitted over the PDCCH.

[@shreyasrai]

If NDI is not toggled then all data of complete resource block for that Uae should be retransmitted ?

[@techLteworld]

@@shreyasrai yes if not toggled it’s the case of retransmission

[@techLteworld]

If the NDI is not toggled, it does not imply that all data of the complete resource block for that UE should be transmitted. Instead, it implies that the current transmission is a retransmission of the previously sent data due to an acknowledgment (ACK) not being received from the UE, indicating the data was not correctly decoded.