Patent ID: 8817719

Claim:
A method in a base station for dynamically triggering a mobile terminal to transmit sounding reference signals (SRS), wherein a predefined uplink symbol of an uplink subframe is configured to be used by the mobile terminal for SRSs, the method comprising: determining whether or not the mobile terminal shall use the predefined uplink symbol for data transmission during uplink transmission; in response to determining that the mobile terminal shall not use the predefined uplink symbol for data transmission during uplink transmission, signaling to the mobile terminal a first instruction comprising: a first part that indicates that the mobile terminal shall not use the predefined uplink symbol for data transmission during uplink transmission; and a second part, distinct from the first part, that indicates one of: that the mobile terminal shall use the predefined uplink symbol for SRSs; or that the mobile terminal shall leave the predefined uplink symbol blank; in response to determining that the mobile terminal shall use the predefined uplink symbol for data transmission during uplink transmission, signaling to the mobile terminal a second instruction indicating that the mobile terminal shall use the predefined uplink symbol only for data transmission during uplink transmission.