# US 10,764,013 B2 · User terminal, radio base station and radio communication method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,764,013 B2 - Document ID: US10764013B2 - Status: Granted - Kind: B2 - Application number: 15/854,457 - Filed: 2017-12-26 - Published: 2018-05-24 - Granted: 2020-09-01 - Earliest claimed: 2015-06-26 - Assignees: Ntt Docomo, Inc. - Applicants: Ntt Docomo, Inc. - Inventors: Kazuki Takeda; Hiroki Harada; Satoshi Nagata; Tooru Uchino - Web page: https://patentgrep.com/patent/US10764013B2 ## CPC - H04L 5/0055: {Physical resource allocation for ACK/NACK (for physical mapping arrangements in ARQ protocols H04L1/1861)} - H04L 1/16: in which the return channel carries supervisory signals, e.g. repetition request signals - H04L 1/1671: {the supervisory signal being transmitted together with control information} - H04W 28/04: Error control - H04W 72/04: Wireless resource allocation - H04W 72/12: Wireless traffic scheduling - H04W 72/23: in the downlink direction of a wireless link, i.e. towards a terminal - H04L 5/001: {the frequencies being arranged in component carriers} - H04W 88/02: Terminal devices - H04W 88/08: Access point devices - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract A user terminal is disclosed including a transmitter that transmits delivery acknowledgment signals (ACK/NACK) in response to downlink (DL) signals transmitted from a plurality of cells, a receiver that receives information about cells to be scheduled, and a processor that controls transmission of the ACK/NACK based on the information about the cells to be scheduled. Further, a radio base station is disclosed that communicates with a user terminal using a plurality cells, the radio base station including a processor that controls scheduling of downlink (DL) signals transmitted respectively from the plurality of cells; a transmitter that transmits information about cells to be scheduled; and a receiver that receives delivery acknowledgement signals (ACK/NACK) transmitted from the user terminal based on the information about the cells to be scheduled. ## Claims ### Claim 1 A user terminal, comprising: a transmitter that transmits delivery acknowledgement signals (ACK/NACK) in response to downlink (DL) signals transmitted from a plurality of cells; a receiver that receives information about a value to represent a total number of cells to be scheduled and a cumulative number of the cells from downlink control information unless the downlink control information is transmitted in a common search space; and a processor that controls transmission of the ACK/NACK based on the information about the value to represent the total number of the cells to be scheduled and the cumulative number of the cells, wherein when the downlink control information is transmitted in the common search space, the downlink control information transmitted in the common search space does not include the information about at least one of the value to represent the total number of the cells to be scheduled and the cumulative number of the cells, and wherein the value to represent the total number of the cells is included with a same value in all downlink control information within a period. ### Claim 2 (depends on 1) The user terminal according to claim 1, wherein the processor controls a bit size of the ACK/NACK to feed back based on the information about the value to represent the total number of the cells to be scheduled and the cumulative number of the cells. ### Claim 3 (depends on 2) The user terminal according to claim 2, wherein, when a maximum value of the cumulative number and the value to represent the total number are different, the processor determines that detection has failed in a given cell. ### Claim 4 (depends on 2) The user terminal according to claim 2, wherein when the receiver is not able to receive a cumulative value of a given cell, the processor decides to feed back NACK in response to a DL signal of the given cell. ### Claim 5 (depends on 2) The user terminal according to claim 2, wherein when the downlink control information does not include at least one of the cumulative value and the value to represent the total number, the processor controls the transmission of the ACK/NACK by using PUCCH format 1a/1b. ### Claim 6 (depends on 2) The user terminal according to claim 2, wherein when the receiver has detected the downlink control information only in the common search space, the processor controls the transmission of the ACK/NACK by applying PUCCH format 1a/1b. ### Claim 7 (depends on 1) The user terminal according to claim 1, wherein, when a maximum value of the cumulative number and the value to represent the total number are different, the processor determines that detection has failed in a given cell. ### Claim 8 (depends on 7) The user terminal according to claim 7, wherein when the receiver is not able to receive a cumulative value of a given cell, the processor decides to feed back NACK in response to a DL signal of the given cell. ### Claim 9 (depends on 7) The user terminal according to claim 7, wherein when the downlink control information does not include at least one of the cumulative value and the value to represent the total number, the processor controls the transmission of the ACK/NACK by using PUCCH format 1a/1b. ### Claim 10 (depends on 1) The user terminal according to claim 1, wherein when the receiver is not able to receive a cumulative value of a given cell, the processor decides to feed back NACK in response to a DL signal of the given cell. ### Claim 11 (depends on 10) The user terminal according to claim 10, wherein when the downlink control information does not include at least one of the cumulative value and the value to represent the total number, the processor controls the transmission of the ACK/NACK by using PUCCH format 1a/1b. ### Claim 12 (depends on 1) The user terminal according to claim 1, wherein when the downlink control information does not include at least one of the cumulative value and the value to represent the total number, the processor controls the transmission of the ACK/NACK by using PUCCH format 1a/1b. ### Claim 13 (depends on 1) The user terminal according to any one of claim 1, wherein when the receiver has detected the downlink control information only in the common search space, the processor controls the transmission of the ACK/NACK by applying PUCCH format 1a/1b. ### Claim 14 A radio base station that communicates with a user terminal connected to a plurality cells, the radio base station comprising: a transmitter that transmits information about a value to represent a total number of cells to be scheduled and a cumulative number of the cells by using downlink control information unless the downlink control information is transmitted in a common search space; and a receiver that receives delivery acknowledgement signals (ACK/NACK) that is transmitted from the user terminal based on the information about the value to represent the total number of the cells to be scheduled and the cumulative number of the cells, wherein when the transmitter transmits the downlink control information in the common search space, the downlink control information transmitted in the common search space does not include the information about at least one of the value to represent the total number of the cells to be scheduled and the cumulative number of the cells, and wherein the value to represent the total number of the cells is included with a same value in all downlink control information within a period. ### Claim 15 A radio communication method for a user terminal that communicates by connecting to a plurality of cells, the radio communication method comprising: receiving information about a value to represent a total number of cells to be scheduled and a cumulative number of the cells from downlink control information unless the downlink control information is transmitted in a common search space; and transmitting delivery acknowledgement signals (ACK/NACK) based on the information about the value to represent the total number of the cells to be scheduled and the cumulative number of the cells, wherein when the downlink control information is transmitted in the common search space, the downlink control information transmitted in the common search space does not include the information about at least one of the value to represent the total number of the cells to be scheduled and the cumulative number of the cells, and wherein the value to represent the total number of the cells is included with a same value in all downlink control information within a period.