Cross-carrier spatial relation indication for semi-persistent sounding reference signal (SP-SRS) resources

A method for a user equipment (UE) to transmit a semi-persistent sounding reference signal (SP-SRS) resource to a network node in a wireless communication network, the method comprising:

• receiving, from the network node, a radio resource control (RRC) message comprising a configuration of a set of SP-SRS resources for transmission in a first serving cell of the wireless communication network;
• receiving, from the network node, a medium access control (MAC) control element (CE) message for activating the configured set of SP-SRS resources, the MAC CE message comprising:
• information identifying an SP-SRS resource of the set of SP-SRS resources to be activated, and the method being characterized in that the MAC CE message comprises:
• an indication of the identified SP-SRS resource's spatial relation with a further resource on a second serving cell different from the first serving cell, wherein the indication comprises an identifier of the further resource and an identifier of the second serving cell;
• and
• transmitting the identified SP-SRS resource using a same spatial domain filter as used to receive or transmit the further resource.

A network node configured to operate in a wireless communication network and to activate semi-persistent sounding reference signal (SP-SRS) resources for transmission by a user equipment (UE), the network node comprising:

• a radio network interface configured for communicating with one or more UEs;
• and
• processing circuitry operatively coupled to the radio network interface, whereby the processing circuitry and the radio network interface are configured to:
• send, to the UE, a radio resource control (RRC) message comprising configuration of a set of SP-SRS resources for UE transmission in a first serving cell of the wireless communication network;
• and
• send, to the UE, a medium access control (MAC) control element (CE) message for activating the configured set of SP-SRS resources, the MAC CE message comprising:
• information identifying an SP-SRS resource of the set of SP-SRS resources to be activated, and
• an indication of the identified SP-SRS resource's spatial relation with a further resource on a second serving cell different from the first serving cell, wherein the indication comprises an identifier of the further resource and an identifier of the second serving cell.

A user equipment (UE) configured to transmit a semi-persistent sounding reference signal (SP-SRS) resource to a network node in a wireless communication network, the UE comprising:

• transceiver circuitry configured for communicating with the network node;
• and
• processing circuitry operatively coupled to the transceiver circuitry, whereby the processing circuitry and the transceiver circuitry are configured to:
• receive, from the network node, a radio resource control (RRC) message comprising a configuration of a set of SP-SRS resources for transmission in a first serving cell of the wireless communication network;
• receive, from the network node, a medium access control (MAC) control element (CE) message for activating the configured set of SP-SRS resources, the MAC CE message comprising:
• information identifying an SP-SRS resource of the set of SP-SRS resources to be activated, and
• an indication of the identified SP-SRS resource's spatial relation with a further resource on a second serving cell different from the first serving cell, wherein the indication comprises an identifier of the further resource and an identifier of the second serving cell;
• and
• transmit the identified SP-SRS resource using a same spatial domain filter as used to receive or transmit the further resource.