Method for transmitting sounding reference signal for user equipment with asymmetric transmit/receive

A method for wireless communication at a user equipment (UE), comprising:

• transmitting a UE capability message to a network device using one or more antennas of the UE, the UE capability message indicating a supported transmit antenna switching (TxAS) capability for each port of the UE, wherein each port of the UE comprises a transmit path performing transmissions using some or all of the one or more antennas of the UE;
• receiving a configuration message from the network device indicating an uplink multiple-input/multiple-output (UL MIMO) configuration for the UE, the UL MIMO configuration being based at least in part on the UE capability message and comprising the use of two or more ports of the UE for UL MIMO communications over two or more spatial layers;
• determining that at least one component carrier (CC) of two or more CCs being transmitted using a first power amplifier is configured for the UL MIMO communications in accordance with the UL MIMO configuration;
• identifying, based at least in part on the UL MIMO configuration and the received configuration message, a sounding reference signal (SRS) configuration to use for transmitting SRSs in conjunction with the UL MIMO communications over the two or more CCs, the SRSs transmitted on the one or more antennas of the UE selected according to a TxAS configuration for the respective port;
• and
• transmitting the SRSs in conjunction with the UL MIMO communications and according to the SRS configuration.

A method for wireless communication at a user equipment (UE), comprising:

• transmitting a UE capability message to a network device using one or more antennas of the UE, the UE capability message indicating a supported transmit antenna switching (TxAS) capability for a plurality of ports of the UE, wherein each port of the plurality of ports of the UE comprises a transmit path performing transmissions using some or all of the one or more antennas of the UE;
• receiving a trigger message from network device indicating that the UE is to perform an aperiodic sounding reference signal (SRS) transmission;
• identifying, based at least in part on the trigger message, a TxAS configuration for the UE to use to transmit the aperiodic SRS transmission;
• and
• transmitting the SRS transmission using the one or more antennas selected based at least in part on the TxAS configuration.

A method for wireless communication at a network device, comprising:

• receiving a user equipment (UE) capability message from a UE using one or more antennas of the UE, the UE capability message indicating a supported transmit antenna switching (TxAS) capability for each port of the UE, wherein each port of the UE comprises a transmit path performing transmissions using some or all of the one or more antennas of the UE;
• transmitting, based at least in part on the UE capability message, a configuration message to the UE indicating an uplink multiple-input/multiple-output (UL MIMO) configuration and a TxAS configuration for the UE, the configuration message indicating a TxAS configuration for the UE to use for transmission of sounding reference signals (SRSs) from each port of the UE;
• and
• receiving the SRSs in conjunction with the UL MIMO communications and according to the TxAS configuration for each port.