# US 10,873,984 B2 · Apparatus related to dual connectivity > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,873,984 B2 - Document ID: US10873984B2 - Status: Granted - Kind: B2 - Application number: 15/759,596 - Filed: 2016-09-28 - Published: 2019-02-07 - Granted: 2020-12-22 - Earliest claimed: 2015-10-06 - Assignees: NEC Corporation - Applicants: NEC Corporation - Inventors: Sadafuku Hayashi - Web page: https://patentgrep.com/patent/US10873984B2 ## CPC - H04W 76/15: Setup of multiple wireless link connections - H04L 5/001: {the frequencies being arranged in component carriers} - H04W 16/32: Hierarchical cell structures - H04W 76/30: Connection release - H04W 76/34: Selective release of ongoing connections - H04W 88/06: adapted for operation in multiple networks {or having at least two operational modes}, e.g. multi-mode terminals - H04W 92/20: between access points - 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 To enable reduction of the occurrence of unnecessary operations in a case with a SCG bearer. An apparatus of the present invention includes: a first communication processing unit configured to communicate with a terminal apparatus over a master cell group (MCG) bearer for dual connectivity of the terminal apparatus; and a second communication processing unit configured to receive, from a secondary base station which communicates with the terminal apparatus over a secondary cell group (SCG) bearer for the dual connectivity, a first message requesting a release of the secondary base station. The second communication processing unit is configured to transmit, to the secondary base station, a second message indicating a rejection of the release. ## Claims ### Claim 1 A master base station for a dual connectivity which communicates with a terminal apparatus over a master cell group (MCG) bearer, the master base station comprising: a receiver configured to receive, from a secondary base station which communicates with the terminal apparatus over a secondary cell group (SCG) bearer for the dual connectivity, a first message requesting a release of the secondary base station; and a transmitter configured to transmit in response to the first message, to the secondary base station, a second message indicating a rejection of the release, wherein the second message includes wait time information indicating a time period for waiting before the secondary base station initiates a next release procedure. ### Claim 2 (depends on 1) The master base station according to claim 1, wherein the first message is an SENB RELEASE REQUIRED message. ### Claim 3 (depends on 1) The master base station according to claim 1, wherein the second message is an SENB RELEASE CONFIRM message including an information element indicating the rejection of the release. ### Claim 4 (depends on 3) The master base station according to claim 3, wherein the information element is a Release Reject information element (IE). ### Claim 5 (depends on 1) The master base station according to claim 1, wherein the second message is an SENB RELEASE REJECT message. ### Claim 6 (depends on 1) The master base station according to claim 1, wherein the transmitter is configured to transmit the second message to the secondary base station when the release is not accepted. ### Claim 7 (depends on 6) The master base station according to claim 6, wherein the transmitter is configured to transmit, to the secondary base station, a third message indicating confirmation of the release, when the release is accepted. ### Claim 8 (depends on 7) The master base station according to claim 7, wherein the third message is an SENB RELEASE CONFIRM message. ### Claim 9 (depends on 1) The master base station according to claim 1, wherein the wait time information is a Time to wait information element (IE). ### Claim 10 (depends on 1) The master base station according to claim 1, wherein the transmitter is configured to transmit, to the secondary base station, stop information indicating stop of a function related to inactivity of the terminal apparatus. ### Claim 11 (depends on 10) The master base station according to claim 10, wherein the stop information is a User Inactivity function Indication information element (IE) indicating the stop. ### Claim 12 (depends on 10) The master base station according to claim 10, wherein the second message includes the stop information. ### Claim 13 (depends on 10) The master base station according to claim 10, wherein the transmitter is configured to transmit, to the secondary base station, an SENB ADDITION REQUEST message including the stop information or an SENB MODIFICATION REQUEST message including the stop information. ### Claim 14 (depends on 1) The master base station according to claim 1, wherein the transmitter is configured to transmit, to the secondary base station, a fourth message including behaviour-related information related to behaviour of the terminal apparatus. ### Claim 15 (depends on 14) The master base station according to claim 14, wherein the behavior-related information is an Expected User Equipment (UE) Behaviour information element (IE). ### Claim 16 (depends on 14) The master base station according to claim 14, wherein the fourth message is an SENB ADDITION REQUEST message or an SENB MODIFICATION REQUEST message. ### Claim 17 A secondary base station for a dual connectivity which communicates with a terminal apparatus over a secondary cell group (SCG) bearer, comprising: a transmitter configured to transmit, to a master base station which communicates with the terminal apparatus over a master cell group (MCG) bearer for the dual connectivity, a first message requesting a release of the secondary base station which communicates with the terminal apparatus over the SCG bearer; and a receiver configured to receive a second message indicating a rejection of the release, the second message being transmitted by the master base station in response to the first message, wherein the second message includes wait time information indicating a time period for waiting before the secondary base station initiates a next release procedure. ### Claim 18 A method of a master base station for a dual connectivity which communicates with a terminal apparatus over a master cell group (MCG) bearer, comprising: receiving, from a secondary base station which communicates with the terminal apparatus over a secondary cell group (SCG) bearer for the dual connectivity, a first message requesting a release of the secondary base station; and transmitting in response to the first message, to the secondary base station, a second message indicating a rejection of the release, wherein the second message includes wait time information indicating a time period for waiting before the secondary base station initiates a next release procedure.