8.7 UE transmit antenna selection

36.2133GPPEvolved Universal Terrestrial Radio Access (E-UTRA)Physical layer proceduresRelease 17TS

UE transmit antenna selection is configured by higher layers via parameter ue-TransmitAntennaSelection. The UE is not expected to be simultaneously configured with SRS-Antenna-Switching-2T4R and ue-TransmitAntennaSelection.

A UE configured with transmit antenna selection for a serving cell is not expected to

– be configured with more than one antenna port for any uplink physical channel or signal for any configured serving cell, or

– be configured with trigger type 1 SRS transmission on any configured serving cell, or

– be configured with simultaneous PUCCH and PUSCH transmission, or

– receive DCI Format 0 indicating uplink resource allocation type 1 for any serving cell, or

– be configured with a SCG.

If UE transmit antenna selection is disabled or not supported by the UE, the UE shall transmit from UE port 0.

If closed-loop UE transmit antenna selection is enabled by higher layers the UE shall perform transmit antenna selection for PUSCH in subframe n in response to the most recent command received via DCI Format 0 in subframe n-4 or earlier (see Clause 5.3.3.2 of [4]).

If a UE is configured with more than one serving cell, and for a group of cells belonging to bands that are signalled to be switched together in txAntennaSwitchUL the UE may assume the same transmit antenna port value is indicated in each PDCCH/EPDCCH with DCI format 0 in a given subframe.

If open-loop UE transmit antenna selection is enabled by higher layers, the transmit antenna for PUSCH to be selected by the UE is not specified.