Communication method and device implementing a network communication procedure with early channel state information acquisition

A method performed by a base station (BS) in a communication system, the method comprising:

• receiving, from a user equipment (UE), a random access preamble on a physical random access channel (PRACH);
• transmitting, to the UE, on a physical downlink shared channel (PDSCH), a random access response (RAR) associated with the random access preamble, wherein the RAR includes a transmit power control (TPC) field, a sounding reference signal (SRS) request field and an SRS TPC field, wherein a value of the TPC field indicates a transmit power for a radio resource control (RRC) connection setup request, a value of the SRS request field indicates whether to transmit the SRS and a value of the SRS TPC field indicates a transmit power for the SRS, and wherein the value of the SRS TPC field is different from the value of the TPC field;
• in case that the value of the SRS request field is one bit and indicates to transmit the SRS, receiving the SRS transmitted by the UE with the transmit power indicated by the SRS TPC field;
• in case that the value of the SRS request field is two bits or three bits and indicates a predetermined configuration of the SRS among a plurality of predetermined configurations, receiving the SRS based on the predetermined configuration indicated by the SRS request field with the transmit power indicated by the SRS TPC field;
• and
• performing one or multiple subsequent downlink transmissions with adaptive spatial signal processing performed based on a channel state information (CSI) obtained based on measurements of the received SRS.

A user equipment (UE) in a communication system, the UE comprising:

• a transceiver;
• and
• a processor coupled with the transceiver and configured to:
• transmit a random access preamble on a physical random access channel (PRACH),
• receive, on a physical downlink shared channel (PDSCH), a random access response (RAR) associated with the random access preamble, wherein the RAR includes a transmit power control (TPC) field, a sounding reference signal (SRS) request field and an SRS TPC field, wherein a value of the TPC field indicates a transmit power for a radio resource control (RRC) connection setup request, a value of the SRS request field indicates whether to transmit the SRS and a value of the SRS TPC field indicates a transmit power for the SRS, and wherein the value of the SRS TPC field is different from the value of the TPC field,
• in case that the value of the SRS request field is one bit and indicates to transmit the SRS, transmit the SRS using the transmit power indicated by the SRS TPC field,
• in case that the value of the SRS request field is two bits or three bits and indicates a predetermined configuration of the SRS among a plurality of predetermined configurations, transmit the SRS based on the predetermined configuration indicated by the SRS request field using the transmit power indicated by the SRS TPC field, and
• receive one or multiple subsequent downlink transmissions with adaptive spatial signal processing based on channel state information (CSI) associated with measurements of the SRS.

A base station (BS) in a communication system, the BS comprising:

• a transceiver;
• and
• a processor coupled with the transceiver and configured to:
• receive, from a user equipment (UE), a random access preamble on a physical random access channel (PRACH),
• transmit, to the UE, on a physical downlink shared channel (PDSCH), a random access response (RAR) associated with the random access preamble, wherein the RAR includes a transmit power control (TPC) field, a sounding reference signal (SRS) request field and an SRS TPC field, wherein a value of the TPC field indicates a transmit power for a radio resource control (RRC) connection setup request, a value of the SRS request field indicates whether to transmit the SRS and a value of the SRS TPC field indicates a transmit power for the SRS, and wherein the value of the SRS TPC field is different from the value of the TPC field,
• in case that the value of the SRS request field is one bit and indicates to transmit the SRS, receive the SRS transmitted by the UE with the transmit power indicated by the SRS TPC field,
• in case that the value of the SRS request field is two bits or three bits and indicates a predetermined configuration of the SRS among a plurality of predetermined configurations, receive the SRS based on the predetermined configuration indicated by the SRS request field with the transmit power indicated by the SRS TPC field, and
• perform one or multiple subsequent downlink transmissions with adaptive spatial signal processing performed based on a channel state information (CSI) obtained based on measurements of the received SRS.