# US 2019/0174502 A1 · Data transmission method and device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0174502 A1 - Document ID: US20190174502A1 - Status: Published application - Kind: A1 - Application number: 16/271,479 - Filed: 2019-02-08 - Published: 2019-06-06 - Earliest claimed: 2016-08-12 - Assignees: Huawei Technologies Co., Ltd. - Applicants: Huawei Technologies Co.,Ltd. - Inventors: Bingzhao Li; Hong Wang; Li Chen; Wei Quan; Jian Zhang - Web page: https://patentgrep.com/patent/US20190174502A1 ## CPC - H04W 72/0453: Resources in frequency domain, e.g. a carrier in FDMA - H04L 1/08: by repeating transmission, e.g. Verdan system {(H04L1/1858 and H04L1/189 take precedence)} - H04L 1/189: {Transmission or retransmission of more than one copy of a message} - H04W 4/06: Selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS]; Services to user groups; One-way selective calling services - H04W 4/70: Services for machine-to-machine communication [M2M] or machine type communication [MTC] - H04W 72/23: in the downlink direction of a wireless link, i.e. towards a terminal - H04L 2001/0093: {Point-to-multipoint} - 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) ## Abstract Embodiments of the present invention relate to the communications field, and disclose a data transmission method and device to resolve a problem that a success rate of receiving data by an MTC terminal is relatively low after an SC-PTM technology is introduced. A specific solution is as follows: A base station device sends first control information to a terminal device, where the first control information is used to control repeated transmission of multicast service data; and the base station device sends the multicast service data to the terminal device according to the first control information. The present invention is used in a data transmission process. ## Claims ### Claim 1 A data transmission method, comprising: sending, by a base station device, first control information to a terminal device, the first control information being used to control retransmission of multicast service data; and sending, by the base station device, the multicast service data to the terminal device according to the first control information. ### Claim 2 (depends on 1) The method according to claim 1, the method further comprising: sending, by the base station device, system information to the terminal device, the system information being used to control retransmission of the first control information. ### Claim 3 (depends on 1) The method according to claim 1, wherein: the first control information comprising a first configuration parameter; and the first configuration parameter comprises first frequency information, the first frequency information being used to indicate a frequency for sending the multicast service data. ### Claim 4 (depends on 1) The method according to claim 1, wherein: the first control information comprising a first configuration parameter; and the first configuration parameter comprises first frequency information, the first frequency information being used to send a third control information, and the first frequency information comprises a narrow band center frequency. ### Claim 5 (depends on 2) The method according to claim 2, wherein: the system information comprising a fourth configuration parameter; the fourth configuration parameter comprising fourth frequency information, the fourth frequency information being used to indicate a frequency for sending the first control information, the fourth frequency information comprising at least one of a narrow band center frequency or a narrow band index value, and the fourth configuration parameter further comprising at least one of a segment quantity or a repetition mode; and the repetition mode comprising alternately transmitting different segment information, or after retransmission of current segment information is complete, retransmitting next segment information. ### Claim 6 A data transmission method, comprising: receiving, by a terminal device, first control information sent by a base station device, the first control information being used to control retransmission of multicast service data; and receiving, by the terminal device according to the first control information, the multicast service data sent by the base station device. ### Claim 7 (depends on 6) The method according to claim 6, further comprising: receiving, by the terminal device, system information sent by the base station device, the system information being used to control retransmission of the first control information. ### Claim 8 (depends on 6) The method according to claim 6, wherein: the first control information comprising a first configuration parameter; and the first configuration parameter comprising first frequency information, the first frequency information being used to indicate a frequency for sending the multicast service data or sending the third control information, and the first frequency information comprising at least one of a narrow band center frequency or a narrow band index value. ### Claim 9 (depends on 6) The method according to claim 6, wherein: the system information comprising a fourth configuration parameter; the fourth configuration parameter comprising fourth frequency information, the fourth frequency information being used to indicate a frequency for sending the first control information, the fourth frequency information comprising at least one of a narrow band center frequency or a narrow band index value, and the fourth configuration parameter further comprising at least one of a segment quantity or a repetition mode; and the repetition mode comprising alternately transmitting different segment information, or after retransmission of current segment information is complete, retransmitting next segment information. ### Claim 10 A data transmission apparatus, comprising: a memory storing instructions; a processor coupled to the memory, the processor executing the instructions to determine first control information, the first control information being used to control retransmission of multicast service data; and a transmitter coupled to the processor, the transmitter configured to send the first control information to a terminal device, and send the multicast service data to the terminal device according to the first control information. ### Claim 11 (depends on 10) The apparatus according to claim 10, wherein the transmitter is further configured to send system information to the terminal device, the system information being used to control retransmission of the first control information. ### Claim 12 (depends on 10) The apparatus according to claim 10, wherein: the first control information comprising a first configuration parameter; and the first configuration parameter comprising first frequency information, the first frequency information being used to indicate a frequency for sending the multicast service data or sending the third control information, and the first frequency information comprising at least one of a narrow band center frequency or a narrow band index value. ### Claim 13 (depends on 10) The apparatus according to claim 10, wherein: the system information sent by the transmitter comprising a fourth configuration parameter; the fourth configuration parameter comprising fourth frequency information, the fourth frequency information being used to indicate a frequency for sending the first control information, the fourth frequency information comprising at least one of a narrow band center frequency or a narrow band index value, and the fourth configuration parameter further comprising at least one of a segment quantity or a repetition mode; and the repetition mode comprising alternately transmitting different segment information, or after retransmission of current segment information is complete, retransmitting next segment information. ### Claim 14 A data transmission apparatus, comprising: a memory storing instructions; a receiver configured to receive first control information sent by a base station device, the first control information being used to control retransmission of multicast service data; and a processor coupled to the memory and to the receiver, the processor executing the instructions to determine a retransmission parameter for the multicast service data according to the first control information; the receiver being further configured to receive the multicast service data according to the retransmission parameter. ### Claim 15 (depends on 14) The apparatus according to claim 14, wherein the receiver is further configured to receive system information sent by the base station device, the system information being used to control retransmission of the first control information. ### Claim 16 (depends on 14) The apparatus according to claim 14, wherein: the first control information received by the receiver comprising a first configuration parameter; and the first configuration parameter comprising first frequency information, the first frequency information being used to indicate a frequency for sending the multicast service data or sending the third control information, and the first frequency information comprising at least one of a narrow band center frequency or a narrow band index value. ### Claim 17 (depends on 14) The apparatus according to claim 14, wherein: the system information received by the receiver comprising a fourth configuration parameter; the fourth configuration parameter comprising fourth frequency information, the fourth frequency information being used to indicate a frequency for sending the first control information, the fourth frequency information comprising a narrow band center frequency, and the fourth configuration parameter further comprising at least one of a segment quantity or a repetition mode; and the repetition mode comprising alternately transmitting different segment information, or after retransmission of current segment information is complete, repeatedly transmitting next segment information.