# US 10,375,584 B2 · Radio base station, user terminal, radio communication system and interference estimation method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,375,584 B2 - Document ID: US10375584B2 - Status: Granted - Kind: B2 - Application number: 14/404,647 - Filed: 2013-05-28 - Published: 2015-07-09 - Granted: 2019-08-06 - Earliest claimed: 2012-06-04 - Assignees: Ntt Docomo, Inc. - Applicants: Ntt Docomo, Inc. - Inventors: Satoshi Nagata; Yoshihisa Kishiyama - Web page: https://patentgrep.com/patent/US10375584B2 ## CPC - H04W 24/02: Arrangements for optimising operational condition - H04J 11/0056: {Inter-base station aspects} - H04L 5/14: Two-way operation using the same type of signal, i.e. duplex - H04L 5/1469: {using time-sharing} - H04W 24/08: Testing, {supervising or monitoring} using real traffic - H04W 88/08: Access point devices - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04J: MULTIPLEX COMMUNICATION (transmission in general H04B; peculiar to transmission of digital information H04L5/00; systems for the simultaneous or sequential transmission of more than one television signal H04N7/08; in exchanges H04Q11/00; stereophonic systems H04S) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract A radio base station is disclosed that receives an uplink signal using a time division duplexing (TDD) scheme, including an estimation section that estimates an interference level that the uplink signal receives in a plurality of subframes of which a downlink/uplink configuration differs among cells and a transmission section that transmits information about the interference level. The information about the interference level comprises interference levels about the plurality of subframes. ## Claims ### Claim 1 A radio base station that receives an uplink signal using a time division duplexing (TDD) scheme, comprising: a processor that estimates an interference level that the uplink signal receives for each of a plurality of subframes of which a downlink/uplink configuration differs among a cell associated with the base station and a neighboring cell associated with another base station; and a transmitter that transmits the interference level for each uplink subframe of the plurality of subframes, wherein the processor estimates the interference level based on received radio resource information specified in subframes associated with subframe index-numbers predetermined by the another base station. ### Claim 2 (depends on 1) The radio base station according to claim 1, wherein the plurality of subframes comprises at least two of subframes #3, #4, #7, #8 and #9 in a radio frame. ### Claim 3 (depends on 2) The radio base station according to claim 2, wherein the processor estimates the interference level in a bandwidth of the radio base station in each of the plurality of subframes. ### Claim 4 (depends on 1) The radio base station according to claim 1, wherein the processor estimates the interference level in a bandwidth of the radio base station in each of the plurality of subframes. ### Claim 5 (depends on 1) The radio base station according to claim 1, wherein the transmitter transmits information about the interference level about all resource blocks of the plurality of subframes. ### Claim 6 A radio communication system comprising: a user terminal; and a radio base station that receives an uplink signal from the user terminal using a time division duplexing (TDD) scheme, the radio base station comprising: a processor that estimates an interference level that the uplink signal receives for each of a plurality of subframes of which a downlink/uplink configuration differs among a cell associated with the base station and a neighboring cell associated with another base station; and a transmitter that transmits the interference level for each uplink subframe of the plurality of subframes, wherein the processor estimates the interference level based on received radio resource information specified in subframes associated with subframe index-numbers predetermined by the another base station. ### Claim 7 (depends on 6) The radio communication system according to claim 6, wherein the plurality of subframes comprises at least two of subframes #3, #4, #7, #8 and #9 in a radio frame. ### Claim 8 (depends on 7) The radio communication system according to claim 7, wherein the processor estimates the interference level in a bandwidth of the radio base station in each of the plurality of subframes. ### Claim 9 (depends on 6) The radio communication system according to claim 6, wherein the processor estimates the interference level in a bandwidth of the radio base station in each of the plurality of subframes. ### Claim 10 (depends on 6) The radio communication system according to claim 6, wherein the transmitter transmits information about the interference level about all resource blocks of the plurality of subframes. ### Claim 11 A radio communication method in a radio communication system having a user terminal and a radio base station that receives an uplink signal from the user terminal using a time division duplexing (TDD) scheme, the radio communication method comprising the steps of: estimating, by the radio base station, an interference level that the uplink signal receives for each of a plurality of subframes of which a downlink/uplink configuration differs among a cell associated with the base station and a neighboring cell associated with another base station; and transmitting, by the radio base station, the interference level for each uplink subframe of the plurality of subframes, wherein estimating the interference level is based on received radio resource information specified in subframes associated with subframe index-numbers predetermined by the another base station. ### Claim 12 (depends on 11) The radio communication method according to claim 11, wherein the plurality of subframes comprises at least two of subframes #3, #4, #7, #8 and #9 in a radio frame. ### Claim 13 (depends on 12) The radio communication method according to claim 12, wherein in the step of estimating, the radio base station estimates the interference level in a bandwidth of the radio base station in each of the plurality of subframes. ### Claim 14 (depends on 11) The radio communication method according to claim 11, wherein in the step of estimating, the radio base station estimates the interference level in a bandwidth of the radio base station in each of the plurality of subframes. ### Claim 15 (depends on 11) The radio communication method according to claim 11, wherein in the step of transmitting, the radio base station transmits information about the interference level about all resource blocks of the plurality of subframes.