WO2013115263A1 - Radio base station and mobile stations - Google Patents

Abstract

The objective of the invention is to facilitate dealing with mobile stations (UE) and determine a cell for which an RA procedure is to be performed in an sTAG. A radio base station (eNB) comprises an RA procedure executing unit (12) that is configured to: perform an RA procedure in a "DL timing reference cell" if it is determined that the "DL timing reference cell" is existent in an sTAG and that the "DL timing reference cell" has been activated; and perform an RA procedure in a "DL timing reference cell" after the activation of the "DL timing reference cell" if it is determined that the "DL timing reference cell" is existent in an sTAG and that the "DL timing reference cell" has not been activated.

Description

Radio base station and mobile station

The present invention relates to a radio base station and a mobile station.

In the LTE (Long Term Evolution) -Advanced system, when there are multiple CCs (Component Carriers, component carriers) with different propagation delays in CA (Carrier Aggregation, Carrier Aggregation), multiples consisting of CCs with almost the same propagation delay "Multiple Timing Advance" that applies different "UL timing alignment control" to each group has been studied.

In such a group, there are two types of pTAG (TA Group) including Pcell (Primary Cell, primary cell) and sTAG consisting only of Scell.

Here, in the pTAG, it is specified that an RA (Random Access, random access) procedure is performed in the Pcell, and the uplink transmission timing in the Scell in the pTAG is determined based on the result of the RA procedure. .

3GPP contribution R2-1116503

However, in the current LTE-Advanced system, it is not specified in which cell the RA procedure should be performed in the sTAG.

Here, if the cell performing the RA procedure (hereinafter referred to as “DL timing reference cell”) is frequently changed, there is a problem that the processing in the mobile station UE becomes complicated.

Accordingly, the present invention has been made in view of the above-described problems, and provides a radio base station and a mobile station that can simplify the processing of the mobile station UE and determine a cell in which an RA procedure should be performed in the sTAG. The purpose is to do.

A first feature of the present invention is a radio base station used in a mobile communication system configured to be able to perform carrier aggregation using a primary cell and a secondary cell, and in a group consisting only of secondary cells The random access procedure executing unit configured to perform a random access procedure in the timing reference cell when it is determined that the timing reference cell exists and the timing reference cell is determined to be activated. The random access procedure execution unit determines that the timing reference cell exists in the group and determines that the timing reference cell is not activated, the timing reference cell The timing reference after activating It is summarized as that is configured to perform a random access procedure in Le.

A second feature of the present invention is a mobile station used in a mobile communication system configured to be able to perform carrier aggregation using a primary cell and a secondary cell. A transmission unit configured to transmit a link signal and a random configuration configured to perform a random access procedure in a timing reference cell within a group including only secondary cells in response to an instruction from the radio base station When the access procedure execution unit and the random access procedure execution unit are performing a random access procedure in the timing reference cell, the transmission unit is in uplink in all secondary cells activated in the group. The main point is that it is configured not to transmit link signals.

FIG. 1 is an overall configuration diagram of a mobile communication system according to a first embodiment of the present invention. FIG. 2 is a functional block diagram of the radio base station according to the first embodiment of the present invention. FIG. 3 is a diagram for explaining the operation of the radio base station according to the first embodiment of the present invention. FIG. 4 is a diagram for explaining the operation of the radio base station according to the first embodiment of the present invention. FIG. 5 is a flowchart showing an operation of the radio base station according to the first embodiment of the present invention. FIG. 6 is a flowchart showing an operation of the radio base station according to the first embodiment of the present invention. FIG. 7 is a flowchart showing an operation of the radio base station according to the first embodiment of the present invention. FIG. 8 is a functional block diagram of a mobile station according to the first modification of the present invention.

(Mobile communication system according to the first embodiment of the present invention)
With reference to FIG.1 and FIG.7, the mobile communication system which concerns on the 1st Embodiment of this invention is demonstrated.

The mobile communication system according to the present embodiment supports the LTE-Advanced scheme and is configured to perform CA using Pcell and Scell.

As shown in FIG. 1, the mobile communication system according to the present embodiment manages a radio base station eNB # 1 that manages a cell # 11, a radio base station eNB # 11A that manages a cell # 11A, and a cell # 11B. Wireless base station eNB # 11B to perform.

For example, the cell # 11 may be a coverage band that supports a wide area, for example, a cell (for example, a macro cell) operated by a carrier (PCC: Primary Component Carrier) having a frequency f1.

On the other hand, the cells # 11A / # 11B are arranged in the cover area of the cell # 11 and have a capacity band for improving the throughput at the hot spot, for example, a carrier of frequency f2 / f3 (SCC: Secondary Component Carrier). ) May be used (for example, a pico cell).

The cell # 11 operated by the carrier of the frequency f1 is set as the Pcell for the mobile station UE, and the cells # 11A / # 11B operated by the carrier of the frequency f2 / f3 are the mobile stations You may be set as Scell with respect to UE.

As shown in FIG. 2, the radio base station eNB # 1 according to the present embodiment includes a management unit 11 and an RA procedure execution unit 12.

The management unit 11 is configured to manage the Pcell and Scell set for each mobile station UE for each group.

Here, the management unit 11 is configured to perform grouping for Pcell and Scell based on each propagation delay.

It is assumed that such grouping is performed based on propagation delay in Pcell and Scell. That is, it is assumed that Pcells and Scells belonging to the same group have the same propagation delay. Note that such grouping is set to Static based on the propagation delay.

For example, as shown in FIG. 3, the management unit 11 is configured to manage a pTAG including Pcell and Cell # 10 and an sTAG including Scell # 1 to Scell # 3 for the mobile station UE. Also good.

Note that Pcell may be a cell operated by a coverage band (for example, a macro cell), and Scell # 1 to # 3 / # 10 are cells operated by a capacity band (for example, a pico cell). It may be.

The RA procedure execution unit 12 is configured to perform the RA procedure in the Pcell and Scell set for each mobile station UE.

Here, the RA procedure execution unit 12 is configured to always perform the RA procedure in the Pcell in the pTAG managed by the management unit 11.

The mobile station UE determines the transmission timing in the Pcell based on the downlink timing (DL timing) obtained by the RA procedure performed in the Pcell, and also determines the transmission timing in another Scell belonging to the pTAG. It is configured as follows.

Further, the RA procedure execution unit 12 is configured to always perform the RA procedure in the “DL timing reference cell” in the sTAG managed by the management unit 11.

That is, the RA procedure execution unit 12 is configured to instruct the mobile station UE to execute the RA procedure using the PDCCH in the “DL timing reference cell”. In such a case, the RA procedure execution unit 12 is configured to notify the mobile station UE of the dedicated RA preamble together with the PDCCH.

Note that the mobile station UE determines the uplink transmission timing in the Scell based on the downlink timing (DL timing) obtained by the RA procedure performed in the “DL timing reference cell”, and other mobile stations UE belonging to the sTAG. The uplink transmission timing in Scell is determined.

Specifically, the RA procedure execution unit 12 determines that the “DL timing reference cell” is present in the sTAG and determines that the “DL timing reference cell” is activated. The “DL timing reference cell” may be configured to perform an RA procedure.

In addition, when the RA procedure execution unit 12 determines that the “DL timing reference cell” exists in the sTAG and determines that the “DL timing reference cell” is not activated, the “DL timing reference” is determined. After activating the “reference cell”, the “DL timing reference cell” may be configured to perform the RA procedure.

In addition, the RA procedure execution unit 12 determines that the “DL timing reference cell” does not exist in the sTAG (for example, the case where the “DL timing reference cell” is deleted or the timing alignment is not started until the CA is started). When it is determined that there is an activated Scell), one of the activated Scells is defined as “DL timing reference cell”, and the “DL timing reference cell” is selected. You may be comprised so that RA procedure may be performed in "timing reference cell".

Here, once the “DL timing reference cell” is set in the sTAG, the “DL timing reference cell” in the sTAG is not changed until the “DL timing reference cell” is deleted by RRC signaling or the like. It is configured.

In addition, when the RA procedure execution unit 12 determines that the “DL timing reference cell” does not exist in the sTAG and determines that there is no activated Scell, the RA procedure execution unit 12 After activating one, the activated Scell may be a “DL timing reference cell”, and the RA procedure may be performed in the “DL timing reference cell”.

In addition, when the RA procedure execution unit 12 determines that the “DL timing reference cell” does not exist in the sTAG and determines that there is an activated Scell, the RA procedure execution unit 12 is the most active Scell. A Scell to which a small Scellindex is assigned may be a “DL timing reference cell”, and the RA procedure may be performed in the “DL timing reference cell”.

For example, as shown in FIG. 4, the RA procedure execution unit 12 determines that “DL timing reference cell” does not exist in the sTAG composed of Scell # 1 to # 3 set for the mobile station UE # 1. And when it is determined that there are activated Scell # 1 to # 3, among the activated Scell # 1 to # 3, Scell # to which the smallest Scellindex (= 1) is assigned 1 may be “DL timing reference cell”, and the RA procedure may be performed in Scell # 1.

In such a case, the RA procedure execution unit 12 replaces the Scell to which the smallest Scellindex is assigned with the Scell to which the largest Scellindex is assigned, the Scell to which the Scellindex satisfying a predetermined condition is assigned, etc. It may be configured to be “timing reference cell”.

Here, as shown in FIG. 4, for each sTAG for each mobile station UE, by changing the carrier operated in Scell # 1 to which the smallest Scellindex (= 1) is allocated, for each carrier, The load distribution of the RA procedure can be performed.

In addition, when the RA procedure execution unit 12 determines that the “DL timing reference cell” does not exist in the sTAG and determines that there is no activated Scell, The Scell to which the smallest Scellindex is assigned may be activated, the activated Scell may be referred to as a “DL timing reference cell”, and the RA procedure may be performed in the “DL timing reference cell”.

For example, as illustrated in FIG. 4, the RA procedure execution unit 12 determines that “DL timing reference cell” does not exist in the sTAG composed of Scell # 1 to # 3 set for the mobile station UE # 2. And when it is determined that there is no activated Scell, activate Scell # 1 to which the smallest Scellindex (= 1) is allocated among Scell # 1 to # 3 which are not activated Then, the activated Scell # 1 may be set as “DL timing reference cell”, and the RA procedure may be performed in Scell # 1.

In such a case, the RA procedure execution unit 12 activates the Scell to which the largest Scellindex is assigned, the Scell to which the Scellindex satisfying the predetermined condition is assigned, instead of the Scell to which the smallest Scellindex is assigned. It may be configured to.

In addition, when the RA procedure execution unit 12 determines that the “DL timing reference cell” does not exist in the sTAG and determines that there is an activated Scell, the RA procedure execution unit 12 is the most active Scell. A Scell with high radio quality may be configured as a “DL timing reference cell”.

In addition, when the RA procedure execution unit 12 determines that the “DL timing reference cell” does not exist in the sTAG and determines that there is no activated Scell, The Scell having the highest radio quality may be configured as “DL timing reference cell”.

Further, when the Scell is set and the set Scell is activated in the state where the Scell is not set, the RA procedure execution unit 12 is assigned the smallest Scellindex among the activated Scells. The existing Scell may be “DL timing reference cell”, and the RA procedure may be performed in “DL timing reference cell”.

In such a case, the RA procedure execution unit 12 replaces the Scell to which the smallest Scellindex is assigned with the Scell to which the largest Scellindex is assigned, the Scell to which the Scellindex satisfying a predetermined condition is assigned, etc. It may be configured to be “timing reference cell”.

Further, the RA procedure execution unit 12 may be configured to determine the “DL timing reference cell” based on a predetermined criterion when it is determined in the sTAG that the “DL timing reference cell” does not exist. .

Hereinafter, operations of the radio base station eNB according to the present embodiment will be described with reference to FIGS.

First, referring to FIG. 5, a radio base in a case where a Scell used in CA is set for the mobile station UE, and a “DL timing reference cell” is set in an sTAG composed only of the Scell. The operation of the station eNB will be described.

As illustrated in FIG. 5, the radio base station eNB determines that the RA procedure is performed in order to perform the timing alignment because the “timing alignment timer” for sTAG has expired in step S101. It is determined whether or not “DL timing reference cell” in the sTAG is activated.

If “YES”, the operation proceeds to step S104, and if “NO”, the operation proceeds to step S103.

In step S103, the radio base station eNB activates the “DL timing reference cell”.

In step S104, the radio base station eNB performs the RA procedure in the “DL timing reference cell”.

Second, referring to FIG. 6, the Scell used in CA is set for the mobile station UE, and the “DL timing reference cell” set in the sTAG consisting only of the Scell is deleted by RRC signaling. The operation of the radio base station eNB in the case where the operation is performed is described.

As illustrated in FIG. 6, when the radio base station eNB detects that “DL timing reference cell” set in the sTAG is deleted by RRC signaling in step S201, the radio base station eNB is active in the sTAG in step S202. It is determined whether there is a converted Scell.

If “YES”, the operation proceeds to step S204, and if “NO”, the operation proceeds to step S203.

In Step S203, when there are a plurality of Scells set in the sTAG, the radio base station eNB activates any one of them.

For example, the radio base station eNB activates the Scell to which the smallest Scellindex is assigned among the Scells set in the sTAG.

In step S104, when there are a plurality of activated Scells in the sTAG, the radio base station eNB designates any one of them as “DL timing reference cell” and RA in the “DL timing reference cell”. Do the procedure.

For example, the radio base station eNB performs the RA procedure in the Scell to which the smallest Scellindex is assigned among the Scells set in the sTAG.

Third, with reference to FIG. 7, the operation of the radio base station eNB in the case where CA is not started will be described.

As illustrated in FIG. 7, in step S301, the radio base station eNB receives “Measurement Report” such as “Event A3 / A4” from the mobile station UE.

In step S302, the radio base station eNB determines the Scell to be additionally set based on the “Measurement Report”, and adds and sets the Scell to the mobile station UE by RRC signaling. To instruct. Here, the additionally set Scell is in an inactive state.

When the radio base station eNB determines to perform scheduling for the downlink data signal or the uplink data signal in Scell in step S303, the radio base station eNB activates the Scell set in step S302 in step S304.

In step S305, when there are a plurality of activated Scells in the sTAG, the radio base station eNB sets one of them as a “DL timing reference cell” and performs the RA procedure in the “DL timing reference cell”. .

For example, the radio base station eNB performs the RA procedure in the Scell to which the smallest Scellindex is assigned among the Scells set in the sTAG.

In step S306, the radio base station eNB performs timing alignment according to the RA procedure, and then performs scheduling for the downlink data signal or the uplink data signal in the Scell.

According to the invention according to the present embodiment, the radio base station eNB is configured to always perform the RA procedure in the “DL timing reference cell” in the sTAG. Therefore, the RA procedure is frequently performed in the sTAG. It is possible to avoid complication of processing in the mobile station UE caused by changing the Scell to be performed.

Further, according to the invention according to the present embodiment, when the radio base station eNB determines that there is no “DL timing reference cell” in the sTAG, the “DL timing reference cell” is determined based on a predetermined criterion. Since it is configured, the RA procedure can be performed in the sTAG by a simple procedure.

(Modification 1)
With reference to FIG. 8, the mobile communication system (especially mobile station UE) which concerns on the modification 1 of this invention is demonstrated. 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.

As illustrated in FIG. 8, the mobile station UE according to the first modification of the present invention includes a management unit 21, a reception unit 22, an RA procedure execution unit 23, and a transmission unit 24.

The management unit 21 is configured to manage the Pcell and Scell set for the mobile station UE for each group.

For example, as illustrated in FIG. 3, the management unit 21 is configured to manage a pTAG including Pcell and Cell # 10 and an sTAG including Scell # 1 to Scell # 3 for the mobile station UE. Also good.

The reception unit 22 is configured to receive a downlink signal transmitted by the radio base station eNB, and the transmission unit 24 is configured to transmit an uplink signal to the radio base station eNB. .

For example, the receiving unit 22 is configured to receive information instructing to perform the RA procedure from the radio base station eNB via the PDCCH. In such a case, the receiving unit 22 is configured to acquire an individual RA preamble.

The RA procedure execution unit 23 is configured to perform an RA procedure in the Pcell and Scell set for the mobile station UE in response to an instruction from the radio base station eNB.

Here, the RA procedure execution unit 23 is configured to always perform the RA procedure in the Pcell in the pTAG managed by the management unit 21.

The transmission unit 24 determines the transmission timing in the Pcell based on the downlink timing (DL timing) obtained by the RA procedure performed in the Pcell, and also determines the transmission timing in another Scell belonging to the pTAG. It is configured as follows.

In addition, the RA procedure execution unit 23 is configured to always perform the RA procedure in the “DL timing reference cell” in the sTAG managed by the management unit 21.

Note that the transmission unit 24 determines the transmission timing in the “DL timing reference cell” based on the downlink timing (DL timing) obtained by the RA procedure performed in the “DL timing reference cell”, and transmits to the sTAG. It is comprised so that the transmission timing in the other Scell to which it belongs may be determined.

Here, when the RA procedure execution unit 23 performs the RA procedure in the “DL timing reference cell” in the sTAG, the transmission unit 24 performs uplink in all the Scells activated in the sTAG. It is configured not to transmit a signal.

Even in such a case, the transmission unit 24 is activated in all Scells activated in the sTAG other than the sTAG in which the above-described RA procedure is performed, or is activated as a Pcell in the pTAG. All of the existing Scells are configured to be able to transmit uplink signals.

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

The first feature of this embodiment is a radio base station eNB used in a mobile communication system configured to perform CA (carrier aggregation) using a Pcell (primary cell) and a Scell (secondary cell). When it is determined that a “DL timing reference cell” exists in an sTAG (group) consisting only of Scells, and it is determined that the “DL timing reference cell” is activated. Includes a RA procedure execution unit (random access procedure execution unit) 12 configured to perform an RA procedure (random access procedure) in the “DL timing reference cell”. When the sequential execution unit 12 determines that the “DL timing reference cell” exists in the sTAG and determines that the “DL timing reference cell” is not activated, the “DL timing reference cell” is determined. After activation, the gist is that the “DL timing reference cell” is configured to perform the RA procedure.

In the first feature of the present embodiment, when the RA procedure execution unit 12 determines that the “DL timing reference cell” does not exist in the sTAG and determines that there is an activated Scell, the RA procedure execution unit 12 is activated. One of the registered Scells is “DL timing reference cell”, and the RA procedure is performed in the “DL timing reference cell”. The RA procedure executing unit 12 performs “DL timing” in the sTAG. If it is determined that there is no “reference cell” and that no activated Scell exists, after activating one of the non-activated Scells, The active of the Scell as "DL timing reference cell", such may be configured to perform a RA procedure in "DL timing reference cell".

In the first feature of the present embodiment, when the RA procedure execution unit 12 determines that the “DL timing reference cell” does not exist in the sTAG and determines that there is an activated Scell, the RA procedure execution unit 12 is activated. The Scell to which the smallest Scellindex (index) is allocated is designated as “DL timing reference cell”, and the RA procedure is configured to perform the RA procedure in this “DL timing reference cell”. execution unit 12, in sTAG, determines that there is no "DL timing reference cell", and determines that the Scell being activated does not exist In this case, after activating the Scell to which the smallest Scellindex is allocated among the Scells that are not activated, the activated Scell is referred to as a “DL timing reference cell”, and the RA in the “DL timing reference cell” is used. It may be configured to perform a procedure.

In the first feature of the present embodiment, when the RA procedure execution unit 12 determines that the “DL timing reference cell” does not exist in the sTAG and determines that there is an activated Scell, the RA procedure execution unit 12 is activated. The Scell with the highest radio quality among the Scells that have been configured is “DL timing reference cell”, and the RA procedure is configured to be performed in the “DL timing reference cell”. , If it is determined that there is no “DL timing reference cell” and that there is no activated Scell, among the non-activated Scells, After activating the radio quality is high Scell, the Activated the Scell as "DL timing reference cell", such may be configured to perform a RA procedure in "DL timing reference cell".

In the first feature of the present embodiment, when the Scell is set and the set Scell is activated in a state where the Scell is not set, the RA procedure execution unit 12 includes the activated Scell. The Scell to which the smallest Scellindex is assigned may be “DL timing reference cell”, and the RA procedure may be performed in “DL timing reference cell”.

The second feature of the present embodiment is a mobile station UE used in a mobile communication system configured to be able to perform CA using Pcell and Scell. In response to an instruction from the radio base station eNB, the transmission unit 24 configured to transmit a link signal, and configured to perform the RA procedure in the “DL timing reference cell” in the sTAG including only Scells. When the RA procedure execution unit 23 and the RA procedure execution unit 23 are performing the RA procedure in the “DL timing reference cell”, the transmission unit 24 transmits the uplink in all Scells activated in the sTAG. The main point is that it is configured not to transmit link signals.

Note that the operations of the radio base station eNB and the mobile station UE described above may be implemented by hardware, may be implemented by a software module executed by a processor, or may be implemented by a combination of both. .

Software modules include RAM (Random Access Memory), flash memory, ROM (Read Only Memory), EPROM (Erasable Programmable ROM), EEPROM (Electronically Erasable and Programmable, Removable ROM, and Hard Disk). Alternatively, it may be provided in a storage medium of an arbitrary format such as a CD-ROM.

The 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 and the mobile station UE. Further, the storage medium and the processor may be provided in the radio base station eNB and the mobile station UE as discrete components.

As described above, the present invention has been described in detail using the above-described embodiments. However, it is obvious for 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 modifications and changes 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.

The entire contents of Japanese Patent Application No. 2012-017367 (filed on January 30, 2012) and Japanese Patent Application No. 2012-060541 (filed on March 16, 2012) are incorporated herein by reference. Built in.

As described above, according to the present invention, it is possible to provide a radio base station and a mobile station that can simplify the processing of the mobile station UE and determine a cell on which an RA procedure should be performed in the sTAG.

eNB ... radio base station 11, 21 ... management unit 12, 23 ... RA procedure execution unit 22 ... reception unit 24 ... transmission unit

Claims (6)

A radio base station used in a mobile communication system configured to be able to perform carrier aggregation using a primary cell and a secondary cell,
When it is determined that there is a timing reference cell in a group consisting only of secondary cells and it is determined that the timing reference cell is activated, a random access procedure is performed in the timing reference cell. A random access procedure executing unit,
If the random access procedure execution unit determines that there is a timing reference cell in the group and determines that the timing reference cell is not activated, after activating the timing reference cell, A radio base station configured to perform a random access procedure in the timing reference cell. If the random access procedure execution unit determines that there is no timing reference cell in the group and determines that there is an activated secondary cell, one of the activated secondary cells One of the timing reference cells is configured to perform a random access procedure in the timing reference cell,
If the random access procedure execution unit determines that there is no timing reference cell in the group, and determines that there is no activated secondary cell, one of the secondary cells that are not activated. 2. The radio base station according to claim 1, wherein the radio base station is configured to use the activated secondary cell as a timing reference cell and perform a random access procedure in the timing reference cell. If the random access procedure execution unit determines that there is no timing reference cell in the group and determines that there is an activated secondary cell, among the activated secondary cells, A secondary cell to which a small index is assigned is set as the timing reference cell, and a random access procedure is performed in the timing reference cell.
When the random access procedure execution unit determines that there is no timing reference cell in the group and determines that there is no activated secondary cell, among the secondary cells that are not activated, The secondary cell to which a small index is allocated is activated, and then the activated secondary cell is set as the timing reference cell, and a random access procedure is performed in the timing reference cell. 2. The radio base station according to 2. If the random access procedure execution unit determines that there is no timing reference cell in the group and determines that there is an activated secondary cell, among the activated secondary cells, A secondary cell with high radio quality is used as the timing reference cell, and a random access procedure is performed in the timing reference cell.
When the random access procedure execution unit determines that there is no timing reference cell in the group and determines that there is no activated secondary cell, among the secondary cells that are not activated, The secondary cell having high radio quality is activated, and then the activated secondary cell is set as the timing reference cell, and a random access procedure is performed in the timing reference cell. Wireless base station. When a secondary cell is set and the set secondary cell is activated in a state where no secondary cell is set, the random access procedure execution unit is the smallest of the activated secondary cells. The radio base station according to claim 1, wherein a secondary cell to which an index is assigned is a timing reference cell, and a random access procedure is performed in the timing reference cell. A mobile station used in a mobile communication system configured to be able to perform carrier aggregation using a primary cell and a secondary cell,
A transmission unit configured to transmit an uplink signal to a radio base station;
In response to an instruction from the radio base station, a random access procedure execution unit configured to perform a random access procedure in a timing reference cell in a group consisting of only secondary cells;
When the random access procedure execution unit performs a random access procedure in the timing reference cell, the transmission unit does not transmit an uplink signal in all secondary cells activated in the group A mobile station characterized in that the mobile station is configured as follows.

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