Patent attributes
The present invention uses user-specific resources, as allocated on the uplink, for conveying one or more antenna-specific sounding reference signals (SRSs). This technique advantageously permits, for example, a user equipment (UE) configured for uplink Multiple-Input-Multiple-Output (MIMO) operation to send antenna-specific SRSs within the granted resources allocated to the UE via one or more scheduled uplink grants. That is, within the granted resources allocated by a given uplink grant, a UE uses at least a portion of those resources for sending antenna-specific SRSs, rather than for sending uplink data (user traffic). Thus, in one or more embodiments, the present invention comprises a method at a UE of transmitting antenna-specific SRSs for two or more uplink transmit antennas. The method comprises transmitting an antenna-specific sounding reference signal for at least one of the uplink transmit antennas within a granted resource allocated to the user equipment for a scheduled uplink data transmission.