JP2013090162A - Mobile station - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mobile station UE capable of knowing which subframe to be used for measurement when transitioning from a Connected mode to an Idle mode.SOLUTION: The mobile station UE comprises a measurement unit 14 configured to perform measurement in a prescribed cell, during subframes for measurement which are indicated by an "RRC Connection Release" received from a radio base station eNB when transitioning from a Connected mode to an Idle mode.

Description

  The present invention relates to a mobile station.

  In “eICIC (Enhanced Inter Cell Interference Coordination)” in the Rel-10 scheme of LTE (Long Term Evolution), the mobile station UE in the connected mode (connection state) is connected to the mobile station UE in the connected mode (connection state) by dedicated RRC (Radio Resource Control Coordination). It is agreed to notify “Pattern”.

  Here, the “Measurement Subframe Pattern” is used for the radio link (Ra) for the radio link (Rk) used by the mobile station UE in the connected mode to measure RSRP (Reference Signal Received Power) and RSRQ (Reference Signal Received Quality). This is information indicating a subframe (measurement processing subframe).

3GPP TS36.300 3GPP TS36.331

  However, in “eICIC” in the LTE Rel-10 scheme, it has not been agreed how to notify “Measurement Subframe Pattern” to the mobile station UE in the idle mode (standby state).

  In particular, the mobile station UE has a problem in that it does not know which subframe should be used for the measurement process when transitioning from the connected mode to the idle mode.

  Therefore, the present invention has been made in view of the above problems, and provides a mobile station that can appropriately know a subframe to be used for measurement processing when a transition is made from the connected mode to the idle mode. Objective.

  The first feature of the present invention is a mobile station, and in a measurement processing subframe notified by a connection release signal received from a radio base station when transitioning from a connected state to a standby state, measurement processing in a predetermined cell The gist of the present invention is to include a measuring unit configured to perform the above.

  A second feature of the present invention is a mobile station configured to perform measurement processing in a predetermined cell in a measurement processing subframe set in the connection state when the mobile station transitions from the connection state to the standby state. The gist is to provide a measuring unit.

  As described above, according to the present invention, it is possible to provide a mobile station that can appropriately know a subframe to be used for measurement processing when a transition is made from the connected mode to the idle mode.

1 is an overall configuration diagram of a mobile communication system according to a first embodiment of the present invention. FIG. 3 is a functional block diagram of a mobile station according to the first embodiment of the present invention. It is a figure for demonstrating operation | movement of the mobile station which concerns on the 1st Embodiment of this invention. FIG. 3 is a sequence diagram showing an operation of the mobile station according to the first embodiment of the present invention.

(Mobile communication system according to the first embodiment of the present invention)
A mobile communication system according to a first embodiment of the present invention will be described with reference to FIGS. In the present embodiment, an LTE mobile communication system will be described as an example of the mobile communication system according to the present embodiment, but the present invention is also applicable to mobile communication systems other than the LTE system.

  The mobile communication system according to the present embodiment is configured to be able to perform “eICIC”.

  As shown in FIG. 1, the mobile communication system according to this embodiment includes a radio base station eNB # 1 that manages a macro cell, a radio base station eNB # 2 that manages a pico cell, and a CSG cell (Femto cell). The radio base station eNB # 3 (HeNB # 3) that manages

  In the mobile communication system according to the present embodiment, the macro cell, the pico cell, and the CSG cell are formed so as to overlap at least partially geographically. Specifically, as shown in FIG. 1, the mobile communication system according to the present embodiment has a configuration in which a macro cell includes a pico cell and a CSG cell.

  In addition, as shown in FIG. 1, the mobile station MUE connected to the macro cell around the pico cell is connected to the pico cell as much as possible for traffic distribution (for example, the cell-specific offset value Cell). A technique called “CRE (Cell Range Expansion)” that sets an individual offset (Individual Offset) may be applied.

  As illustrated in FIG. 2, the mobile station UE includes a storage unit 11, a reception unit 12, a determination unit 13, a measurement unit 14, and a selection unit 15.

  The storage unit 11 is configured to store a measurement processing subframe for the mobile station UE in the idle mode.

  The receiving unit 12 is configured to receive various signals from the radio base stations eNB # 1 to eNB # 3.

  For example, the receiving unit 12 is configured to receive “RRC Connection Release” from the radio base station eNB when the mobile station UE transitions from the connected mode to the idle mode.

  The selection unit 15 is configured to perform selection (selection or reselection) of a standby cell (Cam-on cell) when the mobile station UE transitions from the connected mode to the idle mode.

  Note that the selection unit 15 is configured to identify the type of the standby cell based on the PCI (Physical Cell Identity) of the standby cell.

  In the example of FIG. 1, the selection unit 15 of the mobile station UE (MUE) in the idle mode in the macro cell first performs cell reselection from the macro cell to the pico cell at the point A, and secondly, the point B , The cell reselection from the pico cell to the macro cell is performed.

  Here, the receiving unit 12 may be configured to receive the peripheral pico cell of the selected standby cell, the “PCI range” of the peripheral CSG cell, and the like via the “RRC Connection Release”.

  Further, the reception unit 12 receives information (“Measurement Subframe Pattern”) indicating a measurement processing subframe for the mobile station UE in the idle mode to be used in the selected standby cell via the “RRC Connection Release”. It may be configured to.

  For example, the receiving unit 12 uses the “RRC Connection Release” as information indicating a measurement processing subframe, information indicating a subframe set as measurement processing ABS (Almost Blank Subframe) in a macro cell, The CSG cell is configured to receive information indicating a subframe set as a measurement processing ABS.

  In addition, the receiving unit 12 receives a “Physical Cell ID list” of a pico cell or CSG cell that performs measurement using a subframe set as an ABS (Almost Blank Subframe) for measurement processing via the “RRC Connection Release”. May be configured to receive.

  The determination unit 13 determines whether or not the macro cell is in idle mode, whether or not a condition for performing intra-frequency measurement (intra-frequency measurement processing) is satisfied, and whether or not a CSG cell exists in the vicinity. It may be configured to determine whether or not.

For example, the determination unit 13 is configured to determine that the condition for performing intra-frequency measurement is satisfied when “reception power S _rxlev ≦ S _IntraSearchP ” or “reception quality S _qual ≦ S _IntraSearchQ ” is satisfied. It may be.

  Further, the determination unit 13 uses the “CSG PCI split range” included in the SIB 4 received by the reception unit 12 to determine whether a CSG cell exists in the vicinity (or whether the CSG cell is located in the CSG cell). ) May be determined.

  Alternatively, the determination unit 13 may be configured to detect that the CSG cell has approached and that the CSG cell has moved away.

  For example, the determination unit 13 uses the GPS information, the measurement result in the CSG cell, or the like, that is, the “Proximity Indication function” adopted in the LTE Rel-9 method, that the CSG cell has approached And the CSG cell may be configured to detect that it has moved away.

  The measurement unit 14 is configured to perform measurement processing in a predetermined cell in the above-described measurement processing subframe.

  For example, when the standby cell selected by the selection unit 15 is a macro cell and the determination unit 13 determines that a CSG cell exists in the vicinity (or is located in the CSG cell), the measurement unit 14 Is configured to perform measurement processing in the macro cell (serving cell), the pico cell (neighboring pico cell of the macro cell), and the macro cell surrounding the macro cell in the subframe set as the measurement processing ABS in the CSG cell. Also good.

  In such a case, the measurement unit 14 may be configured to perform measurement processing in the peripheral CSG cell of the macro cell in an arbitrary subframe.

  When the standby cell selected by the selection unit 15 is a macro cell and the determination unit 13 determines that no CSG cell exists in the vicinity (or is located outside the CSG cell), the measurement unit 14 may be configured to perform measurement processing in a neighboring pico cell of the macro cell in a subframe set as a measurement processing ABS in the macro cell.

  In such a case, the measurement unit 14 may be configured to perform measurement processing in such a macro cell (serving cell), a neighboring macro cell of the macro cell, and a neighboring CSG cell of the macro cell in an arbitrary subframe.

  Furthermore, when the standby cell selected by the selection unit 15 is a pico cell, the measurement unit 14 performs the measurement process in the pico cell (serving cell) in the subframe set as the measurement process ABS in the macro cell. It may be configured.

  In this case, the measurement unit 14 may be configured to perform measurement processing in a neighboring macro cell of the pico cell, a neighboring pico cell of the pico cell, and a neighboring CSG cell of the pico cell in an arbitrary subframe.

  In addition, when the measurement unit 14 is notified of the peripheral pico cell, specifically, when the “Physical Cell ID list” of the peripheral pico cell is provided, the measurement unit 14 performs measurement using the measurement processing ABS in the peripheral pico cell. You may be comprised so that a process may be performed.

  Here, it is detected that the determination unit 13 is in a standby state in the macro cell, the condition for performing intra-frequency measurement is satisfied, and a CSG cell exists in the vicinity (or is located in the CSG cell). In the case where it is determined that the measurement is performed, the measurement unit 14 starts measurement processing in the macro cell and the neighboring cells of the macro cell (the neighboring macro cell and the neighboring pico cell) in the subframe set as the measurement processing ABS in the CSG cell. The predetermined timer (T3XX) may be configured to be activated. In such a case, the measurement unit 14 estimates that the mobile station UE exists at the point C.

  The measurement unit 14 may be configured to stop the measurement process in the subframe when the predetermined timer expires, and thereafter perform the measurement process using an arbitrary subframe. It is configured to release such a subframe. In such a case, the measurement unit 14 estimates that the mobile station UE exists at the point D.

  Alternatively, when the determination unit 13 is in a standby state in the macro cell and detects that the CSG cell is approaching, the measurement unit 14 performs the macro cell in the subframe set as the measurement processing ABS in the CSG cell. In addition, it may be configured to start measurement processing in the peripheral cells of the macro cell (the peripheral macro cell and the peripheral pico cell). In such a case, the measurement unit 14 estimates that the mobile station UE exists at the point C.

  When the determination unit 13 detects that the CSG cell has moved away, the measurement unit 14 stops the measurement process in the subframe, and thereafter performs the measurement process using an arbitrary subframe. That is, it is configured to release such a subframe. In such a case, the measurement unit 14 estimates that the mobile station UE exists at the point D.

  Hereinafter, first, referring to FIG. 3, operation example 1 of the mobile station UE according to the present embodiment, specifically, when the mobile station UE (MUE) according to the present embodiment is in the idle mode in the macro cell. The operation example 1 will be described.

  Note that the mobile station UE according to the present embodiment is set as the measurement processing ABS in the macro cell as information indicating the measurement processing subframe via the “RRC Connection Release” when transitioning from the connected mode to the idle mode. It is assumed that the information indicating the subframe being received and the information indicating the subframe set as the measurement processing ABS in the CSG cell are received.

  As illustrated in FIG. 3, when the mobile station UE determines in step S101 that the condition (predetermined condition) for performing intra-frequency measurement is satisfied and the presence of a CSG cell in the vicinity is detected. In step S202, in the subframe set as the measurement processing ABS in the CSG cell, the measurement processing in the macro cell and the surrounding cells of the macro cell (the surrounding macro cell and the surrounding pico cell) is started, and a predetermined timer (T3XX) is started. .

  When detecting that the predetermined timer has expired in step S103, the mobile station UE starts measurement processing in the neighboring picocells of the macrocell in the subframe set as the measurement processing ABS in the macrocell in step S104, Measurement processing is started in a macro cell that is a serving cell and neighboring macro cells using an arbitrary subframe.

  On the other hand, if the mobile station UE re-selects the pico cell in step S105 before detecting that the predetermined timer has expired in step S103, the mobile station UE is set as the measurement processing ABS in the macro cell in step S106. In a subframe, the measurement process in the pico cell (serving cell) is started.

  Secondly, referring to FIG. 4, the operation example 2 of the mobile station UE according to the first modification example, specifically, the case where the mobile station UE (MUE) according to the present embodiment is in a standby state in the macro cell. Operation example 2 will be described.

  Also in the example of FIG. 4, when the mobile station UE according to the present embodiment makes a transition from the connected mode to the idle mode, the information indicating the measurement processing subframe is transmitted in the macro cell via the “RRC Connection Release”. It is assumed that information indicating a subframe set as a measurement processing ABS and information indicating a subframe set as a measurement processing ABS in a CSG cell are received.

  As shown in FIG. 4, when the mobile station UE detects that the CSG cell is approaching in step S201, the mobile station UE uses the macro cell and the sub-frame set as the measurement processing ABS in the CSG cell in step S202. The measurement process in the peripheral cells of the macro cell (peripheral macro cell and peripheral pico cell) is started.

  When the mobile station UE detects that the CSG cell has moved away in step S203, the mobile station UE stops the above-described measurement process in step S204, and in the subframe set as the measurement process ABS in the macro cell, the macro cell The measurement process in the surrounding picocells is started.

  According to the mobile communication system according to the present embodiment, the mobile station UE uses the “RRC Connection Release” received when transitioning from the connected mode to the idle mode as information indicating the subframe for measurement processing in the macro cell. Information indicating a subframe set as a measurement processing ABS and information indicating a subframe set as a measurement processing ABS in a CSG cell can be received, so that the measurement processing used after transitioning to the Idle mode The subframe can be set quickly.

(Modification 1)
Hereinafter, the mobile communication system according to the first modification of the present invention will be described by focusing on the differences from the mobile communication system according to the first embodiment described above.

  In the mobile communication system according to the first modification of the present invention, when the measurement unit 14 of the mobile station UE transitions from the connected mode to the idle mode, the measurement in a predetermined cell is performed in the measurement processing subframe set in the connected mode. It is configured to perform processing.

  For example, when the mobile station UE transitions from the connected mode to the idle mode in the pico cell, the measurement unit 14 measures the measurement processing subframe set in the connected mode (specifically, as the measurement processing ABS in the macro cell). In the set subframe), the measurement process in the pico cell (serving cell) is started.

  Further, when the mobile station UE transitions from the connected mode to the idle mode in the macro cell, and the determination unit 13 determines that there is no CSG cell in the vicinity (or is located outside the CSG cell). The measurement unit 14 starts measurement processing in the neighboring pico cells of the macro cell in the measurement processing sub-frame set in the connected mode (specifically, the sub-frame set as the measurement processing ABS in the macro cell). Is configured to do.

  Alternatively, when the mobile station UE transitions from the connected mode to the idle mode in the macro cell, and the determination unit 13 determines that a CSG cell exists in the vicinity (or is located in the CSG cell), In the measurement processing subframe (specifically, the subframe set as the measurement processing ABS in the CSG cell) that is set in the connected mode, the measurement unit 14 performs the macrocell and the surrounding cells (peripheral of the macrocell). The measurement process in the pico cell and the surrounding macro cell) is started.

  In addition, when the mobile station UE reselects another cell, the measurement unit 14 stops the measurement process in the measurement processing subframe set in the Connected mode, that is, is set in the Connected mode. Alternatively, the measurement processing subframe may be released.

  Alternatively, when the holding timer expires, the measurement unit 14 stops the measurement processing in the measurement processing subframe set in the connected mode, that is, the measurement processing subframe set in the connected mode is stopped. It may be configured to release.

  Note that this holding timer is started when the mobile station UE transitions from the connected mode to the idle mode.

  According to the mobile communication system according to the first modification, when the mobile station UE transitions from the connected mode to the idle mode, the mobile station UE uses the measurement processing subframe set in the connected mode to quickly perform the measurement processing subframe. A frame can be set.

  The characteristics of the present embodiment described above may be expressed as follows.

  The first feature of the present embodiment is the mobile station UE, which receives the “RRC Connection Release (connection release signal) received from the radio base station eNB when transitioning from the connected mode (connected state) to the idle mode (standby state). The gist of the present invention is that the measurement processing subframe notified by “)” includes the measurement unit 14 configured to perform measurement processing in a predetermined cell.

  The second feature of the present embodiment is that the mobile station UE performs measurement processing in a predetermined cell in a measurement processing subframe set in the connected mode when the mobile station UE transitions from the connected mode to the idle mode. The gist of the invention is that the measuring unit 14 is configured.

  In the first and second features of the present embodiment, when the mobile station UE transitions to the idle mode in the pico cell, the measurement unit 14 performs the measurement process in the pico cell in the measurement processing subframe described above, and When notified about the physical ID of the pico cell, the measurement process in the peripheral pico cell may be performed in the measurement processing subframe.

  In the first and second features of the present embodiment, when the mobile station UE transitions to the idle mode in the macro cell and determines that no CSG cell exists in the vicinity, in the measurement processing subframe described above, The measurement processing in the peripheral picocell of the macrocell may be performed.

  In the first and second features of the present embodiment, when the mobile station UE transitions to the idle mode in the macro cell and determines that there is a CSG cell in the vicinity, in the measurement processing subframe described above, The macro cell, the surrounding macro cell of the macro cell, and the surrounding pico cell of the macro cell may be configured to perform measurement processing.

  Note that the operations of the radio base stations eNB # 1 / eNB # 2 / eNB # 3 (HeNB # 3) and the mobile station UE described above may be implemented by hardware or implemented by a software module executed by a processor. It may be carried out by a combination of both.

  The software module includes a RAM (Random Access Memory), a flash memory, a ROM (Read Only Memory), an EPROM (Erasable Programmable ROM), an EEPROM (Electronically Erasable and Programmable ROM, a hard disk, a registerable ROM, a hard disk). Alternatively, it may be provided in a storage medium of an arbitrary format such as a CD-ROM.

  Such a storage medium is connected to the processor so that the processor can read and write information from and to the storage medium. Further, such a storage medium may be integrated in the processor. Such a storage medium and processor may be provided in the ASIC. Such an ASIC may be provided in the radio base station eNB # 1 / eNB # 2 / eNB # 3 (HeNB # 3) or the mobile station UE. Further, the storage medium and the processor may be provided in the radio base station eNB # 1 / eNB # 2 / eNB # 3 (HeNB # 3) or the mobile station UE as a discrete component.

  Although the present invention has been described in detail using the above-described embodiments, it is obvious to those skilled in the art that the present invention is not limited to the embodiments described in this specification. The present invention can be implemented as modified and changed modes without departing from the spirit and scope of the present invention defined by the description of the scope of claims. Therefore, the description of the present specification is for illustrative purposes and does not have any limiting meaning to the present invention.

eNB # 1, eNB # 2, eNB # 3 (HeNB # 3) ... radio base station UE, MUE, PUE ... mobile station 11 ... storage unit 12 ... receiving unit 13 ... determining unit 14 ... measuring unit 15 ... selecting unit

Claims (5)

  A measurement unit configured to perform measurement processing in a predetermined cell in a measurement processing subframe notified by a connection release signal received from a radio base station when transitioning from a connected state to a standby state; A featured mobile station.   A mobile station comprising a measurement unit configured to perform measurement processing in a predetermined cell in a measurement processing subframe set in the connection state when the connection state transits to the standby state .   When the mobile station transitions to the standby state in the pico cell, the measurement unit performs the measurement process in the pico cell in the measurement processing subframe, and when the physical ID of a neighboring pico cell is notified, the measurement unit The mobile station according to claim 1 or 2, wherein the processing subframe is configured to perform measurement processing in the neighboring picocell.   The mobile station is configured to perform measurement processing in a neighboring pico cell of the macro cell in the measurement processing subframe when the mobile station transitions to a standby state in the macro cell and determines that no CSG cell exists in the vicinity. The mobile station according to claim 1, wherein the mobile station is provided.   When the mobile station transitions to a standby state in a macro cell and determines that a CSG cell is present in the vicinity, in the measurement processing subframe, the macro cell, a macro cell in the macro cell, and a pico cell in the macro cell The mobile station according to claim 1, wherein the mobile station is configured to perform a measurement process.

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