Methods, apparatus and computer program products configure a sounding reference signal (SRS) for a segment carrier that serves as a contiguous bandwidth extension of a component carrier, such as a component carrier that is backwards compatible with prior releases of a mobile terminal. In the context of a mobile terminal, the method receives a triggering message that identifies respective configurations of the SRS for the component carrier and the associated segment carrier. The configuration of the SRS for the component carrier is different than the configuration of the SRS for the segment carrier. The method also causes the SRS to be transmitted in accordance with the respective configurations identified by the triggering message via uplink subframes of the component carrier and the segment carrier.