# US 9,439,123 B2 · Base station, radio communication system, and handover method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,439,123 B2 - Document ID: US9439123B2 - Status: Granted - Kind: B2 - Application number: 14/092,597 - Filed: 2013-11-27 - Published: 2014-03-27 - Granted: 2016-09-06 - Earliest claimed: 2008-02-01 - Assignees: Panasonic Intellectual Property Corporation of America - Applicants: Panasonic Intellectual Property Corporation of America - Inventors: Hidenori Matsuo; Takahisa Aoyama; Hong Tat Toh; Hidetoshi Suzuki - Web page: https://patentgrep.com/patent/US9439123B2 ## CPC - H04W 36/0058: {Transmission of hand-off measurement information, e.g. measurement reports} - H04J 11/0069: {Cell search, i.e. determining cell identity [cell-ID] (design of multiplexing codes H04J13/00; processing access restriction or access information H04W48/16; discovery of network devices for network data management H04W8/005; sounding signals for channel estimation H04L25/0226; structure of reference signals in multicarrier modulation systems H04L27/2613; frame, time or carrier synchronisation in multicarrier modulation systems H04L27/2655)} - H04W 4/08: User group management - H04W 36/0061: {of neighbour cell information} - H04W 36/00835: {Determination of neighbour cell lists} - H04W 36/04: Reselecting a cell layer in multi-layered cells - H04W 36/38: by fixed network equipment - H04W 48/02: Access restriction performed under specific conditions - H04W 36/00837: {Determination of triggering parameters for hand-off} - H04W 36/302: {due to low signal strength} - H04W 84/045: {using private Base Stations, e.g. femto Base Stations, home Node B} - H04W 84/105: {PBS [Private Base Station] network (H04W84/12 - H04W84/16 take precedence)} - 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) ## Abstract When a handover request for performing a handover of a terminal (70) from a macro cell C1 to a CSG cell C2 is received from an SeNB 10 (S8), a base station (TeNB) (40) of the CSG cell C2 transmits a handover response in accordance with a handover enabled/disabled state (S12). The handover response includes an identifier of the terminal (70) in the CSG cell C2. Upon receiving the response, the SeNB (10) notifies the identifier to the terminal (70) (S14). The TeNB (40) repeatedly transmits a dedicated signal containing a handover command via a dedicated channel set using the identifier at an interval shorter than a gap period (S18). Accordingly, whether or not access is permitted can be judged promptly and a smooth handover can be realized. ## Claims ### Claim 1 A first radio communication terminal, for use in a radio communication network including a macrocell that is a first type cell and a Closed Subscribers Group (CSG) cell that is a second type cell, wherein the first radio communication terminal has an inbound mobility control function to move to the second type cell, the first radio communication terminal comprising: a communication interface which, in operation, receives a first cell list that is used by both a second radio communication terminal, which does not have the inbound mobility control function to move to the second type cell, and the first radio communication terminal, and a second cell list that includes information about the second type cell and that is used by the first radio communication terminal but is ignored by the second radio communication terminal; a controller, which is coupled to the communication interface and which, in operation, judges a neighboring cell to be a measurement target of reception quality measurement on the basis of the first cell list and the second cell list received via the communication interface; and a receiver which, in operation, repeatedly receives a signal containing a handover command from a target base station in the second type cell at an interval shorter than a period defined for the first radio communication terminal to monitor signals from the target base station in the second type cell. ### Claim 2 (depends on 1) The first radio communication terminal according to claim 1, wherein, when a target cell which is a handover destination candidate is the second type cell, the controller judges whether the first radio communication terminal is able to access the target cell on the basis of notification information received from the target cell, and reports a result of the accessibility judgment and a measurement result of measuring reception quality of the neighboring cell to a source base station via the communication interface. ### Claim 3 (depends on 1) The first radio communication terminal according to claim 1, wherein the second cell list includes information indicating a range of a cell ID of the second type cell. ### Claim 4 (depends on 1) The first radio communication terminal according to claim 1, which is capable of distinguishing between the first type cell and the second type cell based on cell IDs. ### Claim 5 A communication method implemented by a first radio communication terminal in a radio communication network, the network including a macrocell that is a first type cell and a Closed Subscriber Group (CSG) cell that is a second type cell, wherein the first radio communication terminal has an inbound mobility control function to move to the second type cell, the method comprising the steps of: receiving a first cell list that is used by both a second radio communication terminal, which does not have the inbound mobility control function to move to the second type cell, and the first radio communication terminal; receiving a second cell list that includes information about the second type cell and that is used by the first radio communication terminal but is ignored by the second radio communication terminal; judging a neighboring cell to be a measurement target of reception quality measurement on the basis of the first cell list and the second cell list; and repeatedly receiving a signal containing a handover command from a target base station in the second type cell at an interval shorter than a period defined for the first radio communication terminal to monitor signals from the target base station in the second type cell. ### Claim 6 (depends on 5) The communication method according to claim 5, further comprising the steps of: when a target cell which is a handover destination candidate is the second type cell, judging whether the first radio communication terminal is able to access the target cell on the basis of notification information received from the target cell; and reporting a result of the accessibility judgment and a measurement result of measuring reception quality of the neighboring cell to a source base station. ### Claim 7 (depends on 5) The communication method according to claim 5, wherein the second cell list includes information indicating a range of a cell ID of the second type cell. ### Claim 8 (depends on 5) The communication method according to claim 5, wherein the first radio communication terminal is capable of distinguishing between the first type cell and the second type cell based on cell IDs. ### Claim 9 A source base station in a radio communication network, the network including a macrocell that is a first type cell and a Closed Subscriber Group (CSG) cell that is a second type cell, the source base station being of the first type cell and comprising: a communication interface which, in operation, transmits a first cell list that is used by both a first radio communication terminal, which has an inbound mobility control function to move to the second type cell, and a second radio communication terminal, which does not have the inbound mobility control function to move to the second type cell, and a second cell list that includes information about the second type cell and that is used by the first radio communication terminal but is ignored by the second radio communication terminal; and a receiver, which is coupled to the communication interface and which, in operation, receives a measurement result of a neighboring cell from the first radio communication terminal, wherein the first radio communication terminal repeatedly receives a signal containing a handover command from a target base station in the second type cell at an interval shorter than a gap period defined for the first radio communication terminal to monitor signals from the target base station in the second type cell, the gap period being between two periods defined for the first radio communication terminal to monitor signals from the source base station in the first type cell. ### Claim 10 (depends on 9) The source base station according to claim 9, wherein, when a target cell which is a handover destination candidate of the first radio communication terminal is the second type cell, the communication interface receives, from the first radio communication terminal, a judgment result of whether the first radio communication terminal is able to access the target cell judged by the first radio communication terminal on the basis of notification information from the target cell, and the measurement result of the first radio communication terminal measuring reception quality of the neighboring cell. ### Claim 11 (depends on 9) The source base station according to claim 9, wherein the second cell list includes information indicating a range of a cell ID of the second type cell. ### Claim 12 (depends on 9) The base station according to claim 9, wherein the first radio communication terminal is capable of distinguishing between the first type cell and the second type cell based on cell IDs. ### Claim 13 A communication method implemented by a source base station in a radio communication network, the network including a macrocell that is a first type cell and a Closed Subscriber Group (CSG) cell that is a second type cell and the source base station is of the first type cell, the method comprising the steps of: transmitting a first cell list that is used by both a first radio communication terminal, which has an inbound mobility control function to move to the second type cell, and a second radio communication terminal, which does not have the inbound mobility control function to move to the second type cell; transmitting a second cell list that includes information about the second type cell and that is used by the first radio communication terminal but is ignored by the second radio communication terminal; and receiving a measurement result of a neighboring cell from the first radio communication terminal, wherein the first radio communication terminal repeatedly receives a signal containing a handover command from a target base station in the second type cell at an interval shorter than a gap period defined for the first radio communication terminal to monitor signals from the target base station in the second type cell, the gap period being between two periods defined for the first radio communication terminal to monitor signals from the source base station in the first type cell. ### Claim 14 (depends on 13) The communication method according to claim 13, further comprising: when a target cell which is a handover destination candidate of the first radio communication terminal is the second type cell, receiving, from the first radio communication terminal, a judgment result of whether the first radio communication terminal is able to access the target cell judged by the first radio communication terminal on the basis of notification information from the target cell, and a measurement result of the first radio communication terminal measuring reception quality of the neighboring cell. ### Claim 15 (depends on 13) The communication method according to claim 13, wherein the second cell list includes information indicating a range of a cell ID of the second type cell. ### Claim 16 (depends on 13) The communication method according to claim 13, wherein the first radio communication terminal is capable of distinguishing between the first type cell and the second type cell based on cell IDs.