# US 2020/0288509 A1 · Method for performing early data transmission in random access procedure in wireless communication system and apparatus therefor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2020/0288509 A1 - Document ID: US20200288509A1 - Status: Published application - Kind: A1 - Application number: 16/883,216 - Filed: 2020-05-26 - Published: 2020-09-10 - Earliest claimed: 2017-11-15 - Assignees: LG Electronics Inc. - Applicants: LG Electronics Inc. - Inventors: Changhwan PARK; Seokmin SHIN; Joonkui AHN; Seunggye HWANG - Web page: https://patentgrep.com/patent/US20200288509A1 ## CPC - H04W 74/0833: Random access procedures, e.g. with 4-step access - H04W 52/0216: {using a pre-established activity schedule, e.g. traffic indication frame} - H04L 5/0046: {Determination of the number of bits transmitted on different sub-channels} - H04W 52/0209: {in terminal devices} - H04W 74/006: {in the downlink, i.e. towards the terminal} - H04W 74/0838: using contention-free random access [CFRA] - Y02D 30/70: in wireless communication networks - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - Y02D: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE ## Abstract This specification provides a method for performing early data transmission in a random access procedure in a wireless communication system. More specifically, the method performed by a user equipment (UE) includes: receiving, from a base station, a control message including first information indicating whether selection for a second transport size (TBS) smaller than a first TBS for message 3 is permitted and second information for the first TBS; transmitting, to the base station, a request for the EDT by using message 1; receiving, from the base station, message 2 including a UL grant for the message 3; determining a repetition number for the message 3 based on the control message and the UL grant; and transmitting the message 3 to the base station by the repetition number. Therefore, there is an effect that battery consumption of the UE can be reduced. ## Claims ### Claim 1 A method of receiving, by a base station (BS), an uplink data using early data transmission (EDT) in a wireless communication system supporting a narrowband, the method comprising: transmitting, to a user equipment (UE), control information including information representing a maximum transport block size (TBS) for a transmission of the uplink data, receiving, from the UE, a random access preamble for a request of the EDT; transmitting, to the UE, a random access response message; and receiving, from the UE, the uplink data by a repetition number, wherein the repetition number is determined based on a specific TBS. ### Claim 2 (depends on 1) The method of claim 1, wherein the random access preamble is a message 1, the random access response message is a message 2, and the transmission of the uplink data is a message 3. ### Claim 3 (depends on 1) The method of claim 1, wherein the transmission of the uplink data corresponds to a specific coverage enhancement (CE) level. ### Claim 4 (depends on 1) The method of claim 1, further comprising: transmitting, to the UE, second information for a TBS subset including at least one TBS. ### Claim 5 (depends on 4) The method of claim 4, wherein the specific TBS is included in the TBS subset. ### Claim 6 (depends on 5) The method of claim 5, wherein the repetition number is determined based on a repetition number for the transmission of the uplink data configured by the random access response message, the maximum TBS, and the specific TBS. ### Claim 7 (depends on 6) The method of claim 6, wherein the specific TBS is determined based on the maximum TBS. ### Claim 8 (depends on 1) The method of claim 1, wherein a resource in a frequency domain and a start position of a time domain in which the transmission of the uplink data is received are constant regardless of a TBS. ### Claim 9 (depends on 1) The method of claim 1, wherein the random access preamble for the request of the EDT is determined based on at least one of a CE level or reference signal received power (RSRP). ### Claim 10 (depends on 9) The method of claim 9, wherein the random access preamble for the request of the EDT is received from the UE on a carrier corresponding to the CE level. ### Claim 11 (depends on 1) The method of claim 1, further comprising: transmitting, to the UE, a response message for the transmission of the uplink data based on a physical downlink control channel, wherein the physical downlink control channel is monitored in a Type-2 common search space (CSS). ### Claim 12 (depends on 1) The method of claim 1, wherein the random access preamble for the request of the EDT is identified based on at least one of a starting carrier index of an NPRACH, a non-anchor carrier index used for transmission of the NPRACH, or a random access preamble identifier (RAPID). ### Claim 13 (depends on 12) The method of claim 12, wherein the random access response message includes information for a permission or a rejection for the request of the EDT. ### Claim 14 (depends on 13) The method of claim 13, wherein when the request of the EDT is identified based on the RAPID, the permission or rejection is indicated by a specific field of a medium access control (MAC) packet data unit (PDU) corresponding to the RAPID. ### Claim 15 A base station (BS) of receiving an uplink data using early data transmission (EDT) in a wireless communication system supporting a narrowband, the BS comprising: a transmitter and a receiver; and a processor, operatively coupled to the transmitter and the receiver, wherein the processor is configured to: transmit, to a user equipment (UE), control information including information representing a maximum transport block size (TBS) for a transmission of the uplink data, receive, from the UE, a random access preamble for a request of the EDT; transmit, to the UE, a random access response message; and receive, from the UE, the uplink data by a repetition number, wherein the repetition number is determined based on a specific TBS. ### Claim 16 (depends on 15) The BS of claim 15, wherein the processor is further configured to transmit, to the UE, second information for a TBS subset including at least one TBS. ### Claim 17 (depends on 16) The BS of claim 16, wherein the specific TBS is included in the TBS subset. ### Claim 18 (depends on 17) The BS of claim 17, wherein the repetition number is determined based on a repetition number for the transmission of the uplink data configured by the random access response message, the maximum TBS, and the specific TBS.