# US 2018/0324796 A1 · User device, 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 2018/0324796 A1 - Document ID: US20180324796A1 - Status: Published application - Kind: A1 - Application number: 15/773,476 - Filed: 2016-11-02 - Published: 2018-11-08 - Earliest claimed: 2015-11-05 - Assignees: Ntt Docomo, Inc. - Applicants: Ntt Docomo, Inc. - Inventors: Hideaki Takahashi; Wuri Andarmawanti Hapsari; Kazuaki Takeda - Web page: https://patentgrep.com/patent/US20180324796A1 ## CPC - H04W 48/12: using downlink control channel - H04W 72/0446: Resources in time domain, e.g. slots or frames - H04W 28/06: Optimizing {the usage of the radio link}, e.g. header compression, information sizing {, discarding information (system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365)} - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract An object is to provide a user device, a radio base station, and a radio communication method that are capable of extending a predetermined number of spare bits included in notification information such as MIB to be utilized for a plurality of purposes. The user device determines contents of the notification information. The notification information includes a frame (310) having a plurality of slots (410) and a frame (320) having a plurality of slots (420) to each of which system information of a same type is assigned. The system information includes spare bits (500) of 10 bits. The spare bits assigned to the slot (410) are used for a first purpose, and the spare bits assigned to the slot (420) are used for a second purpose that is different from the first purpose. ## Claims ### Claim 1 A user device that performs radio communication with a radio base station based on notification information transmitted from the radio base station, the user device comprising: a notification information receiving unit that receives the notification information repeatedly transmitted from the radio base station at a predetermined cycle; and a notification information determining unit that determines contents of the notification information received by the notification information receiving unit, wherein the notification information includes a first frame having a plurality of first slots to which system information of a same type used to perform the radio communication is assigned; and a second frame that is transmitted after the first frame and has a plurality of second slots to which the system information is assigned, wherein the first frame and the second frame are transmitted at the predetermined cycle, and the system information includes a predetermined number of spare bits, wherein the spare bits assigned to the first slot are used for a first purpose, and the spare bits assigned to the second slot are used for a second purpose that is different from the first purpose, and the notification information determining unit determines contents of the spare bits assigned to the first slot and the contents of the spare bits assigned to the second slot. ### Claim 2 (depends on 1) The user device as claimed in claim 1, wherein even if the contents of the system information included in the first slot and the contents of the system information included in the second slot are different, the notification information determining unit determines that the notification information is not updated. ### Claim 3 (depends on 1) The user device as claimed in claim 1, wherein when the contents of the system information included in the plurality of the first slots that constitute the same first frame, or in the plurality of the second slots that constitute the same second frame are changed, the notification information determining unit determines that the system information has been updated. ### Claim 4 A radio base station that transmits to a user device notification information repeatedly transmitted at a predetermined cycle, the radio base station comprising: a notification information transmitting unit that transmits to the user device the notification information, wherein the notification information includes a first frame having a plurality of first slots to which system information of a same type used to perform radio communication is assigned; and a second frame that is transmitted after the first frame and has a plurality of second slots to which the system information is assigned, wherein, the first frame and the second frame are transmitted at the predetermined cycle, and the system information includes a predetermined number of spare bits, wherein the spare bits assigned to the first slot are used for a first purpose, and the spare bits assigned to the second slot are used for a second purpose that is different from the first purpose. ### Claim 5 A radio communication method used in a radio communication system that includes a user device and a radio base station, the radio communication method comprising: transmitting in which the radio base station repeatedly transmits notification information at a predetermined cycle; and receiving in which the user device receives the notification information, wherein the notification information includes a first frame having a plurality of first slots to which system information of a same type used to perform radio communication is assigned; and a second frame that is transmitted after the first frame, and has a plurality of second slots to which the system information has been assigned, wherein the first frame and the second frame are transmitted at the predetermined cycle, and the system information includes a predetermined number of spare bits, wherein the spare bits assigned to the first slot are used for a first purpose, and the spare bits assigned to the second slot are used for a second purpose which is different from the first purpose.