# US 9,439,182 B2 · Radio communication system, radio base station apparatus, user terminal 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 9,439,182 B2 - Document ID: US9439182B2 - Status: Granted - Kind: B2 - Application number: 14/356,312 - Filed: 2012-11-08 - Published: 2014-11-27 - Granted: 2016-09-06 - Earliest claimed: 2011-11-09 - Assignees: Ntt Docomo, Inc. - Applicants: Ntt Docomo, Inc. - Inventors: Kazuaki Takeda; Liu Liu; Lan Chen; Qin Mu; Wenbo Wang - Web page: https://patentgrep.com/patent/US9439182B2 ## CPC - H04W 72/23: in the downlink direction of a wireless link, i.e. towards a terminal - H04L 1/18: Automatic repetition systems, e.g. Van Duuren systems - H04L 1/1822: involving configuration of automatic repeat request [ARQ] with parallel processes - H04L 1/1887: {Scheduling and prioritising arrangements} - H04L 5/001: {the frequencies being arranged in component carriers} - H04L 5/14: Two-way operation using the same type of signal, i.e. duplex - H04L 1/1812: Hybrid protocols; Hybrid automatic repeat request [HARQ] - H04L 5/0053: {Allocation of signalling, i.e. of overhead other than pilot signals} - 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 The present invention is designed to prevent the decrease of capacity even when the ratio of uplink subframes and downlink subframes is changed in each component carrier in TDD carrier aggregation. With the radio communication method according to the present invention, a radio base station apparatus generates a downlink control channel signal containing downlink control information including carrier indicator field information, and transmits the downlink control channel signal to a user terminal, and the user terminal receives the downlink control channel signal and executes signal processing with respect to the downlink signal in accordance with the downlink control information. In this case, the carrier indicator field information is information which associates a carrier index and the number of subframes to schedule victim subframes. ## Claims ### Claim 1 A radio communication system comprising: a radio base station apparatus; and a user terminal that performs radio communication with the radio base station apparatus by time division duplexing, and which achieves broadbandization by carrier aggregation, wherein: the radio base station apparatus comprises: a processor of the radio base station that generates a downlink control channel signal containing downlink control information including carrier indicator field information; and a transmitter that transmits the downlink control channel signal to the user terminal; and the user terminal comprises: a receiver that receives the downlink control channel signal; and a processor of the user terminal that executes signal processing with respect to a downlink signal in accordance with the downlink control information, wherein the carrier indicator field information is information that associates a carrier index and a number of subframes to schedule victim subframes. ### Claim 2 (depends on 1) The radio communication system according to claim 1, wherein, when a configuration in which there are fewer downlink subframes in a configuration of a primary cell than downlink subframes in a configuration of a secondary cell is used, victim subframes in the secondary cell are scheduled by a super subframe in the primary cell. ### Claim 3 (depends on 2) The radio communication system according to claim 2, wherein a separate HARQ process is applied to scheduling information of each victim subframe by the user terminal. ### Claim 4 (depends on 1) The radio communication system according to claim 1, wherein a separate HARQ process is applied to scheduling information of each victim subframe by the user terminal. ### Claim 5 A radio base station apparatus in a radio communication system, the radio base station apparatus comprising: a processor that generates a downlink control channel signal containing downlink control information including carrier indicator field information; and a transmitter that transmits the downlink control channel signal to a user terminal, wherein the carrier indicator field information is information that associates a carrier index and a number of subframes to schedule victim subframes, and wherein the transmitter transmits using time division duplexing, and the processor of the radio base station achieves broadbandization by carrier aggregation. ### Claim 6 (depends on 5) The radio base station apparatus according to claim 5, wherein, when a configuration in which there are fewer downlink subframes in a configuration of a primary cell than downlink subframes in a configuration of a secondary cell is used, victim subframes in the secondary cell are scheduled by a super subframe in the primary cell. ### Claim 7 (depends on 6) The radio base station apparatus according to claim 6, wherein a separate HARQ process is applied to scheduling information of each victim subframe by the user terminal. ### Claim 8 (depends on 5) The radio base station apparatus according to claim 5, wherein a separate HARQ process is applied to scheduling information of each victim subframe by the user terminal. ### Claim 9 A user terminal in a radio communication system, the user terminal comprising: a receiver that receives a downlink control channel signal containing downlink control information including carrier indicator field information from a radio base station; and a processor that executes signal processing with respect to a downlink signal in accordance with the downlink control information, wherein the carrier indicator field information is information that associates a carrier index and a number of subframes to schedule victim subframes, and wherein a transmitter of the radio base station transmits using time division duplexing, and a processor of the radio base station achieves broadbandization by carrier aggregation. ### Claim 10 A radio communication method in a radio communication system that achieves broadbandization by carrier aggregation, comprising the steps of: at a radio base station apparatus: generating a downlink control channel signal containing downlink control information including carrier indicator field information; and transmitting the downlink control channel signal to a user terminal; and at the user terminal: receiving the downlink control channel signal; and executing signal processing with respect to a downlink signal in accordance with the downlink control information, wherein the carrier indicator field information is information that associates a carrier index and a number of subframes to schedule victim subframes, and wherein a transmitter of the radio base station transmits using time division duplexing, and a processor of the radio base station achieves broadbandization by carrier aggregation. ### Claim 11 (depends on 10) The radio communication method according to claim 10, wherein, when a configuration in which there are fewer downlink subframes in a configuration of a primary cell than downlink subframes in a configuration of a secondary cell is used, victim subframes in the secondary cell are scheduled by a super subframe in the primary cell. ### Claim 12 (depends on 11) The radio communication method according to claim 11, wherein a separate HARQ process is applied to scheduling information of each victim subframe by the user terminal. ### Claim 13 (depends on 10) The radio communication method according to claim 10, wherein a separate HARQ process is applied to scheduling information of each victim subframe by the user terminal.