US Patent 11438916 Sounding reference signal triggering for enhanced carrier aggregation

Methods, systems, and devices for wireless communication are described. A method at a user equipment (UE) includes receiving signaling that indicates a carrier aggregation (CA) configuration (having carriers configured for UL and downlink (DL) data transmissions) and an auxiliary uplink (UL) configuration (having carriers configured for UL reference signal transmissions). The method also includes receiving a resource assignment on a DL carrier of the CA configuration, and transmitting an aperiodic sounding reference signal (A-SRS) using the one or more carriers of the auxiliary UL configuration based at least in part on the received resource assignment. Another method is performed by a UE having a CA configuration and an A-SRS configuration, including receiving a resource assignment on a DL carrier in the CA configuration, detecting a trigger for transmitting an A-SRS, determining UL resources of the A-SRS configuration for transmitting the A-SRS, and transmitting the A-SRS on the determined UL resources.