Method and apparatus for effectively transmitting data of small size in next-generation mobile communication system
The present disclosure relates to a communication technique for combining, with IoT technology, a 5G communication system for supporting a higher data transmission rate than a 4G system, and a system therefor. The present disclosure may be applied to intelligent services, such as smart homes, smart buildings, smart cities, smart cars or connected cars, health care, digital education, retail businesses, and security and safety related services, on the basis of 5G communication technologies and IoT-related technologies. According to various embodiments of the present invention, a method and an apparatus for effectively transmitting data of a small size in a next-generation mobile communication system may be provided.
1 . A method performed by a terminal in a wireless communication system, the method comprising:
receiving, from a base station, system information (SI) including a first threshold value of a data size, a second threshold value of a reference signal received power (RSRP), and small data transmission (SDT)-dedicated random access preamble information for a supplementary uplink (SUL), wherein the first threshold value is associated with initiating an SDT and the second threshold value is associated with selecting the SUL to perform a random access;
identifying whether a data size is less than or equal to the first threshold value associated with initiating the SDT;
in case that the data size is less than or equal to the first threshold value associated with initiating the SDT, identifying whether an RSRP of a pathloss reference is less than the second threshold value associated with selecting the SUL;
in case that the RSRP of the pathloss reference is less than the second threshold value associated with selecting the SUL, selecting the SUL for the SDT;
determining an SDT-dedicated random access preamble allocated to the SUL based on the SDT-dedicated random access preamble information for the SUL;
transmitting, to the base station, the SDT-dedicated random access preamble allocated to the SUL in an uplink bandwidth part (BWP), in a radio resource control (RRC) inactive state;
as a response to the random access preamble allocated to the SUL, receiving, from the base station, a random access response message including an indicator indicating to change from the SUL to a normal uplink (NUL); and
transmitting, to the base station, an RRC resume request message and SDT data via the NUL,
wherein the second threshold value is dedicated for performing the SDT and is applied instead of an RSRP threshold value for determining a SUL for a non-SDT random access,
wherein in case that a separate bandwidth part (BWP) for the SDT is configured via the SI, the random access preamble allocated to the SUL is transmitted in the separate BWP for the SDT, and
wherein in case that the separate BWP for the SDT is not configured via the SI, the random access preamble allocated to the SUL is transmitted in an initial BWP.
2 . A method performed by a base station in a wireless communication system, the method comprising:
transmitting, to a terminal, system information (SI) including a first threshold value of a data size and a second threshold value of a reference signal received power (RSRP), and small data transmission (SDT)-dedicated random access preamble information for a supplementary upling (SUL), wherein the first threshold value is associated with initiating an SDT and the second threshold value is associated with selecting the SUL to perform a random access,
receiving, from the terminal, an SDT-dedicated random access preamble allocated to the SUL in an uplink bandwidth part (BWP) based on the SDT-dedicated random access preamble information for the SUL;
as a response to the random access preamble allocated to the SUL, transmitting, to the terminal, a random access response message including an indicator indicating to change from the SUL to a normal uplink (NUL); and
receiving, from the terminal, a radio resource control (RRC) resume request message and SDT data via the NUL,
wherein the SUL for the SDT is selected in case that a data size is less than or equal to the first threshold value associated with initiating the SDT and an RSRP of a pathloss reference is less than the second threshold value associated with selecting the SUL to perform the random access,
wherein the second threshold value is dedicated for the SDT and applied instead of an RSRP threshold value for determining a SUL for a non-SDT random access,
wherein in case that a separate bandwidth part (BWP) for the SDT is configured via the SI, the random access preamble allocated to the SUL is received in the separate BWP for the SDT, and
wherein in case that the separate BWP for the SDT is not configured via the SI, the random access preamble allocated to the SUL is received in an initial BWP for the SDT.
3 . A terminal in a wireless communication system, the terminal comprising:
a transceiver; and
a controller coupled with the transceiver, and configured to:
receive, from a base station, system information (SI) including a first threshold value of a data size, a second threshold value of a reference signal received power (RSRP), and small data transmission (SDT)-dedicated random access preamble information for a supplementary uplink (SUL), wherein the first threshold value is associated with initiating an SDT and the second threshold value is associated with selecting the SUL to perform a random access,
identify whether a data size is less than or equal to the first threshold value associated with initiating the SDT,
in case that the data size is less than or equal to the first threshold value associated with initiating the SDT, identify whether an RSRP of a pathloss reference is less than the second threshold value associated with selecting the SUL,
in case that the RSRP of the pathloss reference is less than the second threshold value associated with selecting the SUL, select the SUL for the SDT,
determine an SDT-dedicated random access preamble allocated to the SUL based on the SDT-dedicated random access preamble information for the SUL, and
transmit, to the base station, the SDT-dedicated random access preamble allocated to the SUL in an uplink bandwidth part (BWP), in a radio resource control (RRC) inactive state,
as a response to the random access preamble allocated to the SUL, receive, from the base station, a random access response message including an indicator indicating to change from the SUL to a normal uplink (NUL), and
transmit, to the base station, an RRC resume request message and SDT data via the NUL,
wherein the second threshold value is dedicated for performing the SDT and is applied instead of an RSRP threshold value for determining a SUL for a non-SDT random access,
wherein in case that a separate bandwidth part (BWP) for the SDT is configured via the SI, the random access preamble allocated to the SUL is transmitted in the separate BWP for the SDT, and
wherein in case that the separate BWP for the SDT is not configured via the SI, the random access preamble allocated to the SUL is transmitted in an initial BWP for the SDT.
4 . A base station in a wireless communication system, the base station comprising:
a transceiver; and
a controller coupled with the transceiver and configured to:
transmit, to a terminal, system information (SI) including a first threshold value of a data size and a second threshold value of a reference signal received power (RSRP), and small data transmission (SDT)-dedicated random access preamble information for a supplementary uplink (SUL), wherein the first threshold value is associated with initiating an SDT and the second threshold value is associated with selecting the SUL to perform a random access,
receive, from the terminal, an SDT-dedicated random access preamble allocated to the SUL in an uplink bandwidth part (BWP) based on the SDT-dedicated random access preamble information for the SUL,
as a response to the random access preamble allocated to the SUL, transmit, to the terminal, a random access response message including an indicator indicating to change from the SUL to a normal uplink (NUL), and
receive, from the terminal, a radio resource control (RRC) resume request message and SDT data via the NUL,
wherein the SUL for the SDT is selected in case that a data size is less than or equal to the first threshold value associated with initiating the SDT and an RSRP of a pathloss reference is less than the second threshold value associated with selecting the SUL to perform the random access,
wherein the second threshold value is dedicated for the SDT and applied instead of an RSRP threshold value for determining a SUL for a non-SDT random access,
wherein in case that a separate bandwidth part (BWP) for the SDT is configured via the SI, the random access preamble allocated to the SUL is received in the separate BWP for the SDT, and
wherein in case that the separate BWP for the SDT is not configured via the SI, the random access preamble allocated to the SUL is received in an initial BWP for the SDT.