WO2012039289A1

WO2012039289A1 - Communication system, base station device, mobile station device, random access transmission method, and integrated circuit

Info

Publication number: WO2012039289A1
Application number: PCT/JP2011/070475
Authority: WO
Inventors: 克成上村; 恭之加藤; 中嶋　大一郎; 翔一鈴木
Original assignee: シャープ株式会社
Priority date: 2010-09-22
Filing date: 2011-09-08
Publication date: 2012-03-29
Also published as: JP2012070134A

Abstract

In a communication system, a base station device (2) and a mobile station device (1) aggregate a plurality of serving cells to communicate. The serving cells include a deactivated state showing a state where the serving cells are not used for communication and an activated state showing a state where the serving cells are used for communication. The aggregated plurality of serving cells are configured by a primary serving cell which is not deactivated and at least one secondary serving cell which is activated or deactivated. When setting information necessary for a random access procedure in the primary serving cell and the secondary serving cell, the base station device requests the mobile station device to start the random access procedure in the secondary serving cell by activating the secondary serving cell set with the information necessary for the random access procedure. When the secondary serving cell set with the information necessary for the random access procedure by the base station device is activated (S201, S301), the mobile station device starts the random access procedure in the secondary serving cell (S202, S302).

Description

Communication system, base station apparatus, mobile station apparatus, random access transmission method, and integrated circuit

The present invention relates to a communication system, a base station apparatus, a mobile station apparatus, a random access transmission method, and an integrated circuit that efficiently perform random access.

In 3GPP (3rd Generation Partnership Project), which is a standardization project, high-speed communication is achieved by adopting OFDM (Orthogonal Frequency-Division Multiplexing) communication method and a flexible scheduling method of a predetermined frequency and time unit called a resource block. The standardization of the Evolved Universal Terrestrial Radio Access (hereinafter also referred to as “EUTRA”) was realized.

Also, 3GPP is discussing Advanced EUTRA that realizes higher-speed data transmission and has upward compatibility with EUTRA. Carrier aggregation has been proposed as a technology in Advanced EUTRA. Carrier aggregation is a technique for improving a transmission rate by using a plurality of different frequencies (hereinafter also referred to as “component carriers”) in an aggregate manner. Also, it has been proposed that a mobile station apparatus communicating with a base station apparatus using carrier aggregation has a plurality of uplink transmission timings (Timing Advance) for each frequency or component carrier (Non-patent Document 1). And Non-Patent Document 2).

In EUTRA, a random access procedure is prepared to adjust the uplink transmission timing of the mobile station apparatus. In addition to the method in which the mobile station device autonomously determines the necessity of the random access procedure and starts the random access procedure, the base station device sets information indicating the start of the random access procedure in the downlink control channel. There is a method of causing a specific mobile station apparatus to start a random access procedure by transmitting the data.

The base station apparatus configures one cell by combining one downlink component carrier and one uplink component carrier. The base station apparatus can configure one cell with only one downlink component carrier.

As proposed in Non-Patent Document 1, it has a plurality of uplink transmission timings, and each uplink transmission timing is adjusted for each uplink component carrier (or for each uplink component carrier group or each uplink frequency). In such a case, the mobile station apparatus needs to perform a random access procedure for each uplink component carrier. Non-Patent Document 1 and Non-Patent Document 2 describe a method using a downlink control channel and a method using higher layer signaling (RRC signaling, RRC message) in order to start random access.

However, the newly added component carrier is in an inactivated state (details will be described later) in which data transmission / reception is not performed, and the downlink control channel cannot be transmitted to the deactivated component carrier. . Therefore, there is a problem that the EUTRA method of starting a random access to the mobile station apparatus using the downlink control channel cannot be applied to Advanced EUTRA as it is. Regarding this problem, NPL 1 and NPL 2 do not show any specific solution.

Also, in the method using RRC signaling, the message size necessary for starting random access increases. Therefore, when it is necessary to perform random access with a plurality of uplink component carriers, the process of the mobile station apparatus is not only complicated by adjusting the uplink transmission timing repeatedly, but also due to an increase in random access procedures. Another problem arises that the random access collision probability increases.

An object of the present invention is to provide a communication system, a base station apparatus, a mobile station apparatus, a random access transmission method, and an integration that enable efficient random access when the mobile station apparatus needs to adjust a plurality of uplink transmission timings. To provide a circuit.

According to an aspect of the present invention, a communication system is provided in which a base station device and a mobile station device perform communication by aggregating a plurality of serving cells. The serving cell includes an inactivated state indicating a state not used for communication and an activated state indicating a state used for communication. The aggregated plurality of serving cells are configured by a first serving cell that is not deactivated and one or more second serving cells that are activated or deactivated. When the base station apparatus sets information necessary for the random access procedure in the first serving cell and the second serving cell, the base station apparatus activates the second serving cell in which information necessary for the random access procedure is set. To request the mobile station device to start a random access procedure in the second serving cell. When the second serving cell in which information necessary for the random access procedure is set by the base station device is activated, the mobile station device starts the random access procedure in the second serving cell.

Preferably, the base station apparatus activates the second serving cell in which information necessary for the random access procedure is set and notifies the control information necessary for non-contention based random access, thereby allowing the mobile station apparatus to To start a non-contention based random access procedure in the second serving cell.

Preferably, when the base station apparatus requests the mobile station apparatus to start a non-contention based random access procedure in the second serving cell in which information necessary for the random access procedure is set, When activating the serving cell and notifying control information necessary for non-contention based random access and requesting the mobile station device to start the contention based random access procedure in the second serving cell, The second serving cell is activated without notifying control information necessary for non-contention based random access.

More preferably, the mobile station apparatus is notified of control information necessary for non-contention based random access while the second serving cell in which information necessary for the random access procedure is set is activated from the base station apparatus. If this is the case, a non-contention based random access procedure is started using control information in the second serving cell.

More preferably, the mobile station apparatus is activated with the second serving cell in which information necessary for the random access procedure is set by the base station apparatus and is notified of control information necessary for non-contention based random access. Control information necessary for non-contention based random access when the second serving cell is activated and starts the non-contention based random access procedure using the control information in the second serving cell If not, a contention based random access procedure is started in the second serving cell.

Preferably, the activation of the second serving cell is notified by an L2 message.
According to another aspect of the present invention, there is provided a base station apparatus of a communication system in which a base station apparatus and a mobile station apparatus are connected and communicated simultaneously with a plurality of serving cells. The serving cell includes an inactivated state indicating a state not used for communication and an activated state indicating a state used for communication. When the base station apparatus sets the information necessary for the random access procedure to each of the first serving cell that is not deactivated and one or more second serving cells that are activated or deactivated, The mobile station device is requested to start the random access procedure in the second serving cell by activating the second serving cell in which information necessary for the random access procedure is set.

Preferably, the activation of the second serving cell is notified by an L2 message.
According to still another aspect of the present invention, there is provided a base station apparatus of a communication system in which a base station apparatus and a mobile station apparatus are connected and communicated simultaneously with a plurality of serving cells. The serving cell includes an inactivated state indicating a state not used for communication and an activated state indicating a state used for communication. When the base station apparatus sets the information necessary for the random access procedure to each of the first serving cell that is not deactivated and one or more second serving cells that are activated or deactivated, Before the mobile station apparatus starts the random access procedure in the second serving cell, the second serving cell in which information necessary for the random access procedure is set is activated.

According to still another aspect of the present invention, there is provided a mobile station device of a communication system in which a base station device and a mobile station device are connected to perform communication simultaneously with a plurality of serving cells. The mobile station apparatus transmits information necessary for the random access procedure from the base station apparatus to each of the first serving cell that is not deactivated and one or more second serving cells that are activated or deactivated. When set, when the second serving cell in which information necessary for the random access procedure is set is activated, the random access procedure is started in the second serving cell.

Preferably, the mobile station apparatus activates the second serving cell in which information necessary for the random access procedure is set and activates the second cell when the control information necessary for non-contention based random access is notified. Start a non-contention based random access procedure using control information in the serving cell.

Preferably, the mobile station apparatus is notified of control information necessary for non-contention based random access while the second serving cell in which information necessary for the random access procedure is set by the base station apparatus is activated In this case, the non-contention based random access procedure is started using the control information in the second serving cell, and the second serving cell is activated and the control information necessary for the non-contention based random access is notified. If not, start a contention based random access procedure in the second serving cell.

According to still another aspect of the present invention, there is provided a random access transmission method in a mobile station device of a communication system in which a base station device and a mobile station device are connected simultaneously to a plurality of serving cells for communication. The serving cell includes an inactivated state indicating a state not used for communication and an activated state indicating a state used for communication. The aggregated plurality of serving cells are configured by a first serving cell that is not deactivated and one or more second serving cells that are activated or deactivated. In the random access transmission method, when the base station apparatus sets information necessary for the random access procedure in the first serving cell and the second serving cell, the second information in which the information necessary for the random access procedure is set. Requesting the mobile station device to start a random access procedure in the second serving cell by activating the serving cell of the second mobile station device, and the mobile station device setting the information necessary for the random access procedure Starting a random access procedure in the second serving cell when the serving cell is activated.

According to still another aspect of the present invention, there is provided an integrated circuit for performing random access of a mobile station apparatus in a communication system in which a base station apparatus and a mobile station apparatus are connected simultaneously to a plurality of serving cells for communication. The serving cell includes an inactivated state indicating a state not used for communication and an activated state indicating a state used for communication. The integrated circuit sets information necessary for the random access procedure from the base station device to each of the first serving cell that is not deactivated and one or more second serving cells that are activated or deactivated. If the second serving cell in which information necessary for the random access procedure is set is activated, the random access procedure is started in the second serving cell.

In this specification, an implementation related to improvements in a communication system, a base station device, a mobile station device, a random access transmission method, and an integrated circuit when the mobile station device and the base station device are connected using a plurality of frequencies. The form is illustrated. However, the communication method to which the present invention is applicable is not limited to a communication method that is upward compatible with EUTRA such as EUTRA or Advanced EUTRA. For example, the present invention can also be applied to UMTS (Universal Mobile Telecommunications System).

As described above, according to an aspect of the present invention, when a mobile station apparatus that can be connected to a base station apparatus using a plurality of frequencies needs to adjust a plurality of uplink transmission timings, an efficient random A communication system, a base station device, a mobile station device, a random access transmission method, and an integrated circuit that enable access can be provided.

It is a sequence chart for demonstrating the contention based Random Access procedure. It is a sequence chart for demonstrating a Non-contention based Random Access procedure. It is a figure which shows an example of the communication network structure according to embodiment of this invention. It is the figure which showed an example of the setting of the component carrier with respect to the mobile station apparatus according to embodiment of this invention. It is a block diagram which shows schematic structure of the mobile station apparatus according to embodiment of this invention. It is a block diagram which shows schematic structure of the base station apparatus according to embodiment of this invention. It is an example of the figure for demonstrating the component carrier and uplink physical channel which are set to the mobile station apparatus according to embodiment of this invention. It is a sequence chart for demonstrating the addition procedure of the secondary cell according to embodiment of this invention. It is a sequence chart for demonstrating the random access procedure according to the 1st Embodiment of this invention. It is a sequence chart for demonstrating the random access procedure according to the 2nd Embodiment of this invention. It is a flowchart for demonstrating the selection method of the random access procedure according to the 2nd Embodiment of this invention.

Embodiments of the present invention will be described in detail with reference to the drawings. In addition, about the same or equivalent part in a figure, the same code | symbol is attached | subjected and the description is not repeated.

<A. Background Technology>
Before describing the embodiment of the present invention, the carrier aggregation, physical channel, and random access procedure according to the present embodiment will be briefly described.

[A1: Carrier aggregation]
Carrier aggregation is a technology that aggregates (aggregates) a plurality of different frequencies (component carriers or frequency bands) and treats them as one frequency (frequency band). For example, when five component carriers having a frequency bandwidth of 20 MHz are aggregated by carrier aggregation, the mobile station apparatus can access them by regarding these as one frequency bandwidth of 100 MHz. The component carriers to be aggregated may be continuous frequencies, or may be frequencies at which all or part of them are discontinuous. For example, when the usable frequency is in the 800 MHz band, 2.4 GHz band, and 3.4 GHz band, one component carrier is in the 800 MHz band, another component carrier is in the 2 GHz band, and another component carrier is in the 3.4 GHz band. It may be transmitted by.

Also, it is possible to aggregate continuous or discontinuous component carriers in the same frequency band, for example, the 2.4 GHz band. The frequency bandwidth of each component carrier may be a frequency bandwidth narrower than 20 MHz, or each frequency bandwidth may be different. The base station apparatus assigns the uplink and / or downlink to the mobile station apparatus based on various factors such as the amount of data buffer remaining, the reception quality of the mobile station apparatus, the load in the cell and / or QoS. The number of component carriers can be increased or decreased. It is desirable that the number of uplink component carriers assigned by the base station apparatus is the same as or less than the number of downlink component carriers.

[A2: Physical channel]
The main physical channels (or physical signals) used in EUTRA and Advanced EUTRA will be described. A channel means a medium used for signal transmission, and a physical channel means a physical medium used for signal transmission. A physical channel may be added or changed in structure in EUTRA and Advanced EUTRA in the future, but even if it is changed, it does not affect the description of each embodiment of the present invention.

Synchronization signals (Synchronization Signals) are composed of three types of primary synchronization signals and secondary synchronization signals composed of 31 types of codes arranged alternately in the frequency domain. The combination of the primary synchronization signal and the secondary synchronization signal indicates 504 cell identifiers (cell ID: Physical Cell Identity: PCI) for identifying the base station apparatus and frame timing for radio synchronization. The mobile station apparatus identifies the cell ID from the synchronization signal received by the cell search.

The physical broadcast information channel (PBCH: Physical Broadcast Channel) is transmitted for the purpose of notifying control parameters (broadcast information (system information): System information) commonly used by mobile station apparatuses in the cell. The broadcast information not notified by the physical broadcast information channel is transmitted as a layer 3 message (system information) through the physical downlink shared channel, with the radio resource notified by the downlink control channel. As broadcast information, a cell global identifier (CGI) indicating a cell-specific identifier, a tracking area identifier (TAI: Tracking Area Identifier) for managing a standby area by paging, random access control information, and the like are notified. .

The downlink reference signal is a pilot signal transmitted at a predetermined power for each cell. The downlink reference signal is a known signal that is periodically repeated at a frequency and time position based on a predetermined rule. The mobile station apparatus measures the reception quality for each cell by receiving the downlink reference signal. The mobile station apparatus also uses the downlink reference signal as a reference signal for demodulating the physical downlink control channel and / or the physical downlink shared channel transmitted simultaneously with the downlink reference signal. As a sequence used for the downlink reference signal, a sequence that can be identified for each cell is used. The downlink reference signal may be described as cell-specific RS (Cell-specific reference signals), but the use and meaning are the same.

A physical downlink control channel (PDCCH: Physical Downlink Control Channel) is transmitted using several OFDM symbols from the top of each subframe. The physical downlink control channel is used for the purpose of instructing the mobile station apparatus of radio resource allocation information according to the scheduling of the base station apparatus, adjustment amount for increase / decrease of transmission power, and the like. The mobile station apparatus monitors (monitors) the physical downlink control channel addressed to the mobile station apparatus before transmitting / receiving the downlink data and / or the layer 3 message (paging, handover command, etc.) that is the downlink control data. Then, by receiving the physical downlink control channel addressed to the own station, radio resource allocation information called an uplink grant at the time of transmission and a downlink grant (downlink assignment) at the time of reception is transmitted to the physical downlink control channel. Need to get from.

The physical uplink control channel (PUCCH: Physical Uplink Control Channel) is a reception confirmation response (ACK / NACK: Acknowledgement / Negative Acknowledgement) for data transmitted on the physical downlink shared channel. It is used for transmitting a quality request (SR), a scheduling request (SR: Scheduling Request) that is an uplink radio resource request, and the like.

The physical downlink shared channel (PDSCH: Physical Downlink Shared Channel) is used to notify paging and / or broadcast information as a layer 3 message that is downlink control data in addition to downlink data. The radio resource allocation information of the physical downlink shared channel is indicated by the physical downlink control channel.

The physical uplink shared channel (PUSCH: Physical Uplink Shared Channel) mainly transmits uplink data and uplink control data, and can also include control data such as downlink reception quality and ACK / NACK. . Similarly to the downlink, the radio resource allocation information of the physical uplink shared channel is indicated by the physical downlink control channel.

A physical random access channel (PRACH: Physical Random Access Channel) is a channel used to notify a preamble sequence and has a guard time. The preamble sequence includes 64 types of sequences, and is configured to express 6-bit information. The physical random access channel is used as a means for accessing the base station apparatus of the mobile station apparatus. The mobile station apparatus uses radio resources when the physical uplink control channel is not set and transmission timing adjustment information (timing advance (TA)) necessary to match the uplink transmission timing with the reception timing window of the base station apparatus. The physical random access channel is used to request the base station apparatus. Specifically, the mobile station apparatus transmits a preamble sequence using the radio resource for the physical random access channel set by the base station apparatus. The mobile station apparatus that has received the transmission timing adjustment information sets a transmission timing timer (TA timer) that counts the effective time of the transmission timing adjustment information. During the effective time, the transmission timing adjustment state is set, and outside the effective period, the transmission timing is not adjusted. Manage states as states. Since the other physical channels are not related to this embodiment, detailed description thereof will not be given.

[A3: Random access procedure]
A series of procedures associated with random access is referred to as a random access procedure. In EUTRA, there are two random access procedures: a contention based random access (contention based random access) procedure and a non-contention based random access (non-contention based random access) procedure, both of which are physical random access channels. It is done using.

The Contention based Random Access procedure is a random access procedure in which preamble sequences transmitted by different mobile station devices may collide (contention), and the mobile station device is not connected (communication) with the base station device. For initial access, it is used for a scheduling request for requesting uplink transmission resources from a state in which the mobile station apparatus is connected to the base station apparatus. The collision of preamble sequences means that a plurality of mobile station apparatuses transmit a physical random access channel using the same preamble sequence using the same frequency and time resource. Note that a preamble sequence collision is also referred to as a random access collision.

The Non-contention based Random Access procedure is a random access procedure in which no collision occurs in preamble sequences transmitted by different mobile station devices, and the mobile station device is connected to the base station device, and uplink synchronization. Is started in response to an instruction from the base station apparatus. The Non-contention based Random Access procedure is instructed by an RRC (Radio Resource Control: Layer 3) layer message and control data of the physical downlink control channel PDCCH.

The preamble sequence (dedicated preamble) used in the Non-contention based Random Access procedure is individually notified from the base station apparatus to the mobile station apparatus. The preamble sequence used in the Contention based Random Access procedure is used after the mobile station apparatus randomly selects one preamble sequence that is not used as an individual preamble during random access. Among the preamble sequences that can be used by the mobile station apparatus in a certain cell, the number of preamble sequences used in each of the contention based random access procedure and the non-contention based random access procedure is notified from the base station apparatus.

The content based random access procedure will be briefly described with reference to FIG. First, the mobile station apparatus 1 selects a preamble sequence (random access preamble) selected based on the downlink radio propagation path state (path loss) and / or the size of the message 3 (message transmitted in step S3). It transmits to the base station apparatus 2 (step S1). The base station device 2 that has received the random access preamble calculates a transmission timing shift amount between the mobile station device 1 and the base station device 2 from the random access preamble, and transmits the response to the random access preamble (random access response). It transmits to the mobile station apparatus 1 including the transmission timing adjustment information for adjusting the timing shift (step S2).

The mobile station device 1 confirms the content of the random access response. When the preamble number corresponding to the transmitted random access preamble is included in the random access response, the mobile station apparatus 1 adjusts the uplink transmission timing from the transmission timing adjustment information. When adjusting the transmission timing, the mobile station apparatus 1 starts a transmission timing timer (TA timer) that effectively reflects the adjusted transmission timing.

Also, the mobile station apparatus 1 transmits an upper layer message (upper layer message) to the base station apparatus 2 based on the scheduling information included in the random access response (step S3). The base station apparatus 2 transmits a collision confirmation message (Contention resolution) to the mobile station apparatus 1 that has received the upper layer message of Step S3 (Step S4), and completes the procedure.

The non-contention based Random Access procedure will be briefly described with reference to FIG. First, the base station apparatus 2 notifies the mobile station apparatus 1 of the number of the dedicated preamble and the number of the physical random access channel to be used (random access channel number) (random access preamble allocation) (step S11). The random access channel number is a number indicating a physical random access channel to which the dedicated preamble may be transmitted, and the base station device 2 notifies the mobile station device 1. For example, a certain random access channel number indicates that a dedicated preamble may be transmitted in all physical random access channels, and another random access channel number is dedicated in every two physical random access channels in the time direction. Indicates that a preamble may be transmitted.

The mobile station apparatus 1 transmits a preamble sequence (individual preamble) corresponding to the designated preamble number through a physical random access channel indicated by the random access channel number and permitted to transmit the dedicated preamble (step S12). . The base station apparatus 2 that has received the dedicated preamble calculates a transmission timing shift amount between the mobile station apparatus 1 and the base station apparatus 2 from the dedicated preamble, and transmits transmission timing adjustment information for adjusting the transmission timing shift. A response to the dedicated preamble (random access response) is transmitted to the mobile station apparatus 1 (step S13), and the procedure is completed.

However, when the value of the preamble number notified from the base station apparatus 2 is “0”, the mobile station apparatus 1 performs the Contention based Random Access procedure instead of the Non-contention based Random Access procedure. In this case, the mobile station apparatus 1 completes the procedure according to the procedure of steps S1 to S4 in FIG.

<B. Example of communication network configuration according to embodiment>
FIG. 3 is a diagram showing an example of a communication network configuration according to the embodiment of the present invention. When the mobile station apparatus 1 can wirelessly connect to the base station apparatus 2 by using a plurality of frequencies (component carriers Band1 to Band3) simultaneously by carrier aggregation, the communication network configuration includes a certain base station apparatus 2 has transmitters 11 to 13 (and receivers 21 to 23 (not shown)) for each of a plurality of frequencies, and a configuration in which control of each frequency is performed by one base station device 2 is a viewpoint of simplifying control. To preferred. The configuration of the base station apparatus 2 is not limited to the form shown in FIG. For example, the base station apparatus 2 may be configured to transmit a plurality of frequencies using a single transmission apparatus because the plurality of frequencies are continuous. Furthermore, a configuration in which transmission / reception timing differs for each frequency may be employed. The number of transmitting devices and receiving devices and / or the frequencies that can be transmitted and received may be different. The communicable range of each frequency controlled by the transmission device of the base station device 2 is regarded as a cell. At this time, the areas (cells) covered by each frequency may have different widths or different shapes.

However, in the description below, the areas covered by the frequency of the component carrier that the base station apparatus 2 configures will be referred to as cells, but this is the definition of a cell in a communication system that is actually operated. Note that it can be different. For example, in some communication systems, some of the component carriers used by carrier aggregation may be defined simply as additional radio resources rather than cells. Moreover, it may be defined as an extended cell different from the conventional cell. By referring to the component carrier as a cell in the present specification, even if a case that differs from the definition of a cell in a communication system that is actually operated occurs, the gist of the present invention is not affected. Carrier aggregation is communication by a plurality of cells using a plurality of component carriers, and is also referred to as cell aggregation. Note that the mobile station device 1 may be wirelessly connected to the base station device 2 via a relay station device (or repeater) for each frequency. That is, base station apparatus 2 according to the present embodiment can be replaced with a relay station apparatus.

The third generation base station apparatus 2 defined by 3GPP is referred to as Node B (Node B), and the base station apparatus in EUTRA and Advanced EUTRA is referred to as E Node B (eNode B). Note that the third-generation mobile station apparatus 1 defined by 3GPP is referred to as UE (User Equipment). The base station apparatus 2 manages cells that are areas in which the mobile station apparatus 1 can communicate. The cell is also referred to as a macro cell, a femto cell, a pico cell, or a nano cell depending on the size of an area that can communicate with the mobile station apparatus 1. When the mobile station device 1 can communicate with a certain base station device 2, a cell used for communication with the mobile station device 1 among the cells of the base station device 2 is a serving cell. And the other cells are referred to as neighboring cells. That is, when the mobile station apparatus 1 and the base station apparatus 2 communicate using a plurality of cells using carrier aggregation, there are a plurality of serving cells.

<C. Setting example of component carrier configuration>
FIG. 4 shows the correspondence between downlink component carriers set by the base station device 2 for the mobile station device 1 and uplink component carriers when the mobile station device 1 according to the embodiment of the present invention performs carrier aggregation. It is the figure which showed an example of the relationship. FIG. 4 shows the correspondence relationship between two downlink component carriers (downlink component carriers DL_CC1 and DL_CC2) and two uplink component carriers (uplink component carriers UL_CC1 and UL_CC2). It is not limited to component carriers. In FIG. 4, cell-specific connection is performed between the downlink component carrier DL_CC1 and the uplink component carrier UL_CC1 and between the downlink component carrier DL_CC2 and the uplink component carrier UL_CC2. Yes.

The cell-specific connection is, for example, a correspondence relationship (cooperation relationship) between the uplink and downlink frequency bands accessible to the base station device 2 when the mobile station device 1 is not carrier-aggregated. Specifically, the correspondence relationship is indicated by a part of the broadcast information (SIB2: System Information Block Type2). The cell specific connection is also referred to as SIB2 linkage. The correspondence relationship between the uplink and downlink frequencies in the cell is explicitly indicated as frequency information in the broadcast information. Alternatively, when not explicitly instructed, the correspondence relationship of the frequency is implicitly instructed by using information on a predetermined frequency difference between the uplink and the downlink uniquely determined for each operating frequency. . In addition to these methods, other methods may be used as long as the correspondence relationship between the uplink and downlink frequency bands can be shown for each cell.

On the other hand, the base station apparatus 2 individually sets the correspondence between the downlink component carrier and the uplink component carrier for each mobile station apparatus 1 separately from the cell specific connection (individual connection: UE Specific Linkage). It is also possible. At this time, the setting of the individual connection is indicated by the RRC message. The base station apparatus 2 can also assign a plurality of configurations (configurations) necessary for transmission of the physical random access channel for each uplink component carrier or each uplink frequency.

In consideration of the above matters, preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In the description of the present embodiment, when it is determined that a specific description of known functions and configurations related to the present invention obscures the gist of the present invention, a detailed description thereof will not be given. .

<D. First Embodiment>
A first embodiment of the present invention will be described below.

This embodiment relates to a random access transmission method at the time of carrier aggregation of the mobile station apparatus 1, and particularly shows a random access transmission method when the mobile station apparatus 1 manages a plurality of uplink transmission timings.

FIG. 5 is a block diagram showing an example of the mobile station apparatus 1 according to the first embodiment of the present invention. The mobile station apparatus 1 includes a receiving unit 101, a demodulating unit 102, a decoding unit 103, a measurement processing unit 104, a control unit 105, a random access control unit 106, an encoding unit 107, a modulation unit 108, and a transmission Unit 109, timing management unit 110, and upper layer 111. The upper layer 111 includes RRC (Radio Resource Control) that performs radio resource control. The random access control unit 106 functions as a part of a MAC (Medium Access Control) that manages the data link layer.

Prior to reception, mobile station apparatus control information is input from the upper layer 111 to the control unit 105. Control information relating to reception is appropriately input as reception control information from the control unit 105 to the reception unit 101, the demodulation unit 102, and the decoding unit 103. The mobile station apparatus control information is information necessary for radio communication control of the mobile station apparatus 1 configured by reception control information and transmission control information, and is set by the base station apparatus 2 and / or system parameters. Is input to the control unit 105 as necessary. The reception control information includes information such as reception timing, multiplexing method, and radio resource arrangement information regarding each channel in addition to information on the reception frequency band.

The received signal is received by the receiving unit 101. The receiving unit 101 receives a signal in the frequency band specified by the reception control information. The received signal is input to the demodulation unit 102. Demodulation section 102 demodulates the received signal and inputs the signal to decoding section 103. The decoding unit 103 correctly decodes the downlink data and the downlink control data, and inputs each decoded data to the upper layer. The measurement processing unit 104 measures the reception quality (SIR, SINR, RSRP, RSRQ, RSSI, path loss, etc.) of the downlink reference signal for each cell (component carrier) and / or physical downlink control channel or physical downlink Based on the measurement result of the reception error rate of the shared channel, downlink measurement information is generated, and the downlink measurement information is output to the upper layer 111. The downlink measurement information is used for detection of a radio link failure (Radio link failure) with radio link re-establishment and radio link monitoring (Radio link monitoring) with stop of uplink transmission in the upper layer 111. .

Also, prior to transmission, mobile station apparatus control information is input from the upper layer 111 to the control unit 105. Control information related to transmission is appropriately input from the control unit 105 to the random access control unit 106, the encoding unit 107, the modulation unit 108, and the transmission unit 109 as transmission control information. The transmission control information includes information such as encoding information, modulation information, transmission frequency band information, transmission timing for each channel, multiplexing method, and radio resource arrangement information as uplink scheduling information of the transmission signal. The random access control information is input from the upper layer 111 to the random access control unit 106. The random access control information includes preamble information, radio resource information for physical random access channel transmission, and the like. The upper layer 111 sets transmission timing adjustment information and a transmission timing timer used for adjusting the uplink transmission timing in the timing management unit 110 as necessary. The timing management unit 110 manages the uplink transmission timing state (transmission timing adjustment state or transmission timing non-adjustment state) based on the set information.

The encoding unit 107 receives uplink data and uplink control data from the upper layer 111 and random access data information related to transmission of the physical random access channel from the random access control unit 106. The encoding unit 107 generates a preamble sequence transmitted through the physical random access channel based on the random access data information. Further, encoding section 107 appropriately encodes each data according to transmission control information, and outputs the encoded data to modulation section 108. Modulating section 108 modulates the output from encoding section 107. The transmission unit 109 maps the output of the modulation unit 108 to the frequency domain, converts the frequency domain signal into a time domain signal, and performs power amplification on a carrier wave of a predetermined frequency. Furthermore, the transmission unit 109 adjusts the uplink transmission timing according to the transmission timing adjustment information input from the timing management unit 110 and transmits the transmission timing adjustment information. A physical uplink shared channel in which uplink control data is arranged typically constitutes a layer 3 message (radio resource control message: RRC message). In FIG. 5, other components of the mobile station device 1 are not described because they are not related to the present embodiment.

FIG. 6 is a block diagram showing an example of the base station apparatus 2 according to the first embodiment of the present invention. The base station apparatus 2 includes a reception unit 201, a demodulation unit 202, a decoding unit 203, a control unit 204, an encoding unit 205, a modulation unit 206, a transmission unit 207, an upper layer 208, and a network signal transmission / reception unit. 209.

The higher layer 208 inputs downlink data and downlink control data to the encoding unit 205. The encoding unit 205 encodes the input data and inputs it to the modulation unit 206. The modulation unit 206 modulates the encoded signal. The signal output from the modulation unit 206 is input to the transmission unit 207. The transmission unit 207 maps the input signal to the frequency domain, converts the frequency domain signal into a time domain signal, transmits the signal with a predetermined frequency carrier wave, and amplifies the power. The physical downlink shared channel in which downlink control data is arranged typically constitutes a layer 3 message (RRC message).

Also, the reception unit 201 converts the signal received from the mobile station device 1 into a baseband digital signal. The digital signal is input to the demodulation unit 202 and demodulated. The signal demodulated by the demodulator 202 is subsequently input to the decoder 203 and decoded. Decoding section 203 outputs correctly decoded uplink control data and / or uplink data to higher layer 208. The base station apparatus control information necessary for control of each block is information necessary for radio communication control of the base station apparatus 2 configured by reception control information and transmission control information, and a higher-level network apparatus (MME or gateway). Device) and / or system parameters, and the upper layer 208 inputs to the control unit 204 as necessary. The control unit 204 appropriately inputs base station apparatus control information related to transmission as transmission control information to each block of the encoding unit 205, modulation unit 206, and transmission unit 207, and receives base station apparatus control information related to reception. The reception control information is appropriately input to each block of the reception unit 201, the demodulation unit 202, and the decoding unit 203. The RRC of the base station device 2 exists as part of the upper layer 208.

Meanwhile, the network signal transmission / reception unit 209 transmits and / or receives control messages between the base station devices 2 or between the host network device and the base station device 2. In FIG. 6, other components of the mobile station device 2 are not described because they are not related to the present embodiment.

Further, the network configuration of the communication system in which the mobile station device 1 and the base station device 2 are arranged can be the same as that shown in FIG.

FIG. 7 shows an example of the configuration of a cell (component carrier) set in the mobile station apparatus 1 capable of carrier aggregation and uplink physical channel setting according to the present embodiment. FIG. 7 illustrates an example in which two cells, that is, two downlink component carriers (DL_CC1, DL_CC2) and two uplink component carriers (UL_CC1, UL_CC2) are set in the mobile station apparatus 1. In the example of FIG. 7, component carriers that are cell-specifically connected with DL_CC1 and UL_CC1 and DL_CC2 and UL_CC2 as pairs are set for the mobile station apparatus 1 as the cell configuration. When the activation of these component carriers is explicitly or implicitly instructed from the base station apparatus 2, the mobile station apparatus 1 uses two frequencies for downlink reception and uplink transmission, respectively. Can be used. On the other hand, when deactivation of a component carrier is explicitly or implicitly instructed, the mobile station apparatus 1 cannot perform downlink reception and uplink transmission with the deactivated component carrier. . Inactivation may be managed as a pair of downlink and uplink, or may be managed independently.

Here, the activation or deactivation of the component carrier is configured to be controlled by an L2 message (layer 2 message) that can be interpreted by a layer 2 configuration task. That is, activation or deactivation is controlled by a control command recognized by layer 2 after being decoded by the physical layer (layer 1). The L2 message in EUTRA and Advanced EUTRA is notified by a control command (MAC control element: MAC Control Element) interpreted in the MAC layer.

Further, as the uplink physical channel setting, the transmission setting of the physical uplink control channel used for the radio resource request (uplink control channel setting for radio resource request) is set only to UL_CC1. The uplink component carriers of UL_CC1 and UL_CC2 have different physical random access channel transmission settings (random access channel settings). That is, the mobile station apparatus 1 needs to manage the UL_CC1 and UL_CC2 transmission timing adjustment information, TA timer, transmission timing adjustment state / transmission timing non-adjustment state independently for each uplink component carrier.

A cell composed of an uplink component carrier in which an uplink control channel for radio resource request is set and a downlink component carrier that is cell-specifically connected to the uplink component carrier is called a primary cell (Primary cell). The Moreover, the cell comprised from component carriers other than a primary cell is called a secondary cell (Secondary cell). The primary cell is not subject to activation / inactivation control (that is, it is always considered to be activated), but the secondary cell has an activation / inactivation state. These state changes can be explicitly specified by the base station apparatus 2 or can be changed based on a timer set in the mobile station apparatus 1 for each component carrier.

Further, the mobile station apparatus 1 detects a radio link failure in the primary cell based on the parameter specified by the base station apparatus 2, and monitors the radio link using the parameter in at least the activated secondary cell. To do.

The mobile station apparatus 1 may stop monitoring the uplink grant and the downlink grant used for scheduling the deactivated component carrier (secondary cell). The mobile station apparatus 1 may stop transmission of an uplink pilot channel called a sounding reference signal (SRS) regarding the uplink of the deactivated component carrier (secondary cell). The mobile station apparatus 1 may perform measurement at a sampling rate lower than the activated state with respect to the downlink of the deactivated component carrier (secondary cell).

Note that the present invention is not limited to the example of FIG. 7, and a plurality of uplink component carriers are set in the mobile station apparatus 1 as carrier aggregation, and a plurality of random access channel settings are set in different uplinks. As long as the link component carrier is set, it can be applied to any configuration. For example, a pair of uplink and downlink component carriers constituting a secondary cell (or a secondary cell having only a downlink) is not cell-specific but is set individually by the base station device 2 for each mobile station device 1. Also good.

FIG. 8 is a sequence for explaining a procedure for adding a secondary cell so that the mobile station device 1 and the base station device 2 according to the first embodiment start communication in a plurality of cells by carrier aggregation. It is a chart.

In FIG. 8, the mobile station apparatus 1 selects a suitable cell (suitable cell) of the base station apparatus 2 by performing a cell search procedure for selecting an optimal cell, and is camping in the cell (idle mode). ) Starts processing. That is, the terminal information (UE context) of the mobile station apparatus 1 is already registered in the network via the base station apparatus 2, and the MME holds the information of the mobile station apparatus 1. At this time, when the mobile station apparatus 1 shifts to the connected state (connected mode) with the cell of the base station apparatus 2 by the incoming call calling process and / or the outgoing call process by paging, the mobile station apparatus 1 uses the contention based described in FIG. The Random Access procedure is started (step S101). The Contention based Random Access procedure at this time is always executed in the primary cell.

The mobile station apparatus 1 that has completed the Contention based Random Access procedure transmits a mobile station apparatus capability information message to the base station apparatus 2 (step S102). The mobile station apparatus capability information message is at least (a) the mobile station apparatus 1 is capable of carrier aggregation using a plurality of component carriers (cells), and (b) the frequency band used for carrier aggregation and receivable. And the number of random carriers or the number of component carriers, and (c) that a plurality of random access settings are possible for a random access setting that is a setting for performing a plurality of random accesses. By receiving the mobile station apparatus capability information message, the base station apparatus 2 can know that the mobile station apparatus 1 can perform a plurality of random access settings, thereby performing appropriate random access settings. be able to.

Subsequently, when a measurement configuration for measuring a neighboring cell including a frequency different from the frequency of the serving cell is set from the base station device 2, the mobile station device 1 sets the neighboring cell according to the measurement setting. Start measurement. Then, the mobile station device 1 transmits a result of measurement based on the set measurement setting included in a message (measurement report message) (step S103). The base station apparatus 2 comprehensively determines the measurement result reported in the measurement report message, the current load of the own apparatus, the traffic volume, etc., and instructs the mobile station apparatus 1 to add a secondary cell. An additional message is transmitted (step S104).

In the secondary cell addition message, at least information such as downlink frequency ID and cell ID, secondary cell ID, and bandwidth for identifying the secondary cell is set. In addition, when the secondary cell to be added is a cell operated at an uplink transmission timing different from the uplink transmission timing of the primary cell of the mobile station device 1, the base station device 2 sets the random access setting (random access resource, Information necessary for a random access procedure such as a preamble sequence, a downlink component carrier used for path loss calculation, and transmission timing timer information is set in the secondary cell addition message.

The mobile station apparatus 1 confirms the received secondary cell addition message, and when it is confirmed that the parameters are correctly set, adds the secondary cell based on the set parameters. At this time, the added secondary cell is added in an inactivated state. And when the addition of a secondary cell is completed, the mobile station apparatus 1 transmits a secondary cell addition completion message with respect to the base station apparatus 2 (step S105). The process is then complete.

Each control message in FIG. 8 may reuse an existing RRC message in EUTRA. For example, the mobile station device capability information message is a UE Capability Information message, the measurement report message is a Measurement Report message, the secondary cell addition message is an RRC Connection Reconfiguration message, and the secondary cell addition completion message is an RRC Connection Reconfiguration Complete parameter. Reuse is possible just by doing.

Here, the secondary cell instructed to be added by the base station apparatus 2 is a cell having an uplink transmission timing different from that of the primary cell, and is newly added while the uplink transmission timing of the primary cell is adjusted. When starting communication using the secondary cell, the mobile station apparatus 1 needs to adjust the uplink transmission timing of the secondary cell by performing a random access procedure, and start management of uplink transmission timing different from the primary cell. There is.

FIG. 9 shows a method for the base station apparatus 2 according to the present embodiment to start a random access procedure in a secondary cell (or secondary cell group) having an uplink transmission timing different from the primary cell of the mobile station apparatus 1. It is the sequence chart shown. In order to notify the mobile station apparatus 1 whether the uplink transmission timing is the same, the base station apparatus 2 sets a transmission timing group ID (TA group ID) indicating the same uplink transmission timing when adding a secondary cell. It may be configured to set.

When the TA group ID notified when the secondary cell is added is different from the held TA group ID, the mobile station apparatus 1 determines that the uplink transmission timing of the added secondary cell is different. By assigning a fixed value (eg, “0”) to the TA group ID value including the primary cell, the mobile station apparatus 1 is not notified until it is necessary to manage a plurality of uplink transmission timings. May be.

The base station device 2 notifies the mobile station device 1 of a command for activating the secondary cell, and requests activation of the secondary cell (step S201). Hereinafter, activating a secondary cell is also referred to as “secondary cell activation”. At this time, as a cell to be activated, a plurality of secondary cells may be designated at the same time. Moreover, you may comprise so that activation and inactivation may be designated simultaneously. The command for activating the secondary cell is typically notified by an L2 message. The secondary cell activation command is preferably indicated using a MAC control element. The base station apparatus 2 may transmit the secondary cell activation command in the primary cell of the mobile station apparatus 1 or may be transmitted in any secondary cell that has already been activated.

The mobile station apparatus 1 instructed by the base station apparatus 2 to activate a secondary cell having a different uplink transmission timing activates the secondary cell and starts the Contention based Random Access procedure (step S202). The Contention based Random Access procedure may be the same as the procedure described in FIG. However, each step (step S1 to step S4) in the contention based random access procedure at this time is transmitted / received on the uplink or downlink of the secondary cell.

The L2 message related to the secondary cell activation transmitted in step S201 in FIG. 9 may be the same as the L2 message used for the conventional secondary cell activation. Here, as a specific control method, when (1) activation of the downlink component carrier and activation of the corresponding uplink component carrier are performed simultaneously, (2) activation of the downlink component carrier and uplink A case where the activation of the component carrier is performed separately will be described as an example.

In the case of example (1), when the activation of the downlink of the secondary cell is notified by the L2 message from the base station device 2, the mobile station device 1 has a random access setting for the secondary cell to be activated. If so, it is determined that the random access procedure is requested in the uplink corresponding to the downlink, and the random access procedure is started. The uplink correspondence relationship corresponding to the downlink is indicated by cell-specific connection by broadcast information or individual connection by RRC message.

For example, the individual connection indicates a relationship with a downlink component carrier used for calculation of a path loss necessary for transmission power control of the uplink component carrier. For example, the individual connection indicates a relationship with a downlink component carrier that receives a physical downlink control channel necessary for an uplink component carrier transmission schedule.

The mobile station apparatus 1 ignores the received L2 message when activation is requested for a secondary cell having a transmission timing different from that of the primary cell and there is no random access setting corresponding to the secondary cell. You may be comprised so that it may be comprised, and it may be comprised so that only the activation of a secondary cell may be performed, without starting a random access procedure.

In addition, the mobile station apparatus 1 is a case where activation is requested for a secondary cell having a transmission timing different from that of the primary cell, and there is a random access setting corresponding to the secondary cell. When in the transmission timing adjustment state, it may be configured to activate only the secondary cell without starting the random access procedure. That is, when the activation of the downlink of the secondary cell is notified by the L2 message from the base station device 2, the mobile station device 1 has a random access setting for the secondary cell to be activated, and the transmission timing is not set. When in the adjustment state, it may be determined that a random access procedure is requested in the uplink corresponding to the downlink, and the random access procedure may be started.

Further, the mobile station device 1 is a case where activation of the secondary cell is requested, and when there is a random access setting corresponding to the uplink of the secondary cell and the transmission timing is not adjusted, It may be determined that the condition is satisfied.

In the case of the example (2), when the activation of the downlink of the secondary cell is notified from the base station apparatus 2 by the L2 message, the mobile station apparatus 1 performs only the activation of the downlink, and the downlink No control is performed for the corresponding uplink. On the other hand, when the activation of the uplink of the secondary cell is notified and the random access setting exists in the downlink corresponding to the uplink, the mobile station device 1 determines that the random access procedure is requested. The random access procedure is started according to the downlink random access setting corresponding to the uplink. The downlink correspondence relationship corresponding to the uplink is indicated by cell-specific connection by broadcast information or individual connection by RRC message.

The mobile station apparatus 1 is a case where activation is requested for the uplink of the secondary cell at a transmission timing different from that of the primary cell, and there is a random access setting in the downlink corresponding to the uplink of the secondary cell. If not, it may be configured to ignore the received L2 message, or may be configured to activate only the secondary cell without starting the random access procedure.

Further, the mobile station apparatus 1 is a case where activation is requested for the uplink of the secondary cell having a transmission timing different from that of the primary cell, and the mobile station apparatus 1 sets random access to the downlink corresponding to the uplink of the secondary cell. However, when the uplink of the secondary cell is in the transmission timing adjustment state, the activation of the uplink of the secondary cell may be performed without starting the random access procedure. That is, when the activation of the secondary cell uplink is notified by the L2 message from the base station device 2, the mobile station device 1 has a random access setting for the downlink corresponding to the uplink, and When the uplink is in a transmission timing non-adjusted state, it may be determined that a random access procedure is requested, and the random access procedure may be started according to the downlink random access setting corresponding to the uplink.

Furthermore, the mobile station apparatus 1 satisfies the above-described conditions in the example (1) or the example (2), but the uplink secondary cell that performs the random access procedure refers to the downlink of the secondary cell that is referred to for path loss calculation. May be configured to ignore the received L2 message. Alternatively, it may be configured to activate only the secondary cell without starting the random access procedure. “Receiving quality is degraded” typically indicates a state in which a certain time has elapsed since the downlink reference signal of the secondary cell does not satisfy the predetermined receiving quality.

In addition, when the mobile station apparatus 1 satisfies the above-described conditions in the example (1) or the example (2), but uplink transmission is prohibited in the secondary cell performing the random access procedure, the mobile station apparatus 1 transmits the received L2 message. It may be configured to be ignored. Alternatively, it may be configured to activate only the secondary cell without starting the random access procedure. “Uplink transmission is prohibited” typically means that the SRS, physical uplink control channel, physical uplink shared channel, etc. are set, but the transmission of these physical channels is the upper layer. (Typically RRC) indicates a state of being stopped.

In addition, the L2 message related to the secondary cell activation transmitted in step S201 in FIG. 9 includes at least an index number indicating that the control command indicating activation or deactivation is included, and activation or deactivation. Information indicating a secondary cell to be activated is set. As an example, information indicating the secondary cell is indicated by a bitmap table. At this time, for example, when the received bitmap table is “1”, the mobile station device 1 activates the secondary cell. When the received bitmap table is “0”, the mobile station device 1 activates the secondary cell. Inactivate. The meanings of activation and deactivation indicated by the bitmap may be reversed. The association between the bit position of the bitmap table and the secondary cell may be notified by the RRC message. Further, the order of bits in the bitmap table may match the order of secondary cell IDs (ascending order or descending order).

As another example, the information indicating the secondary cell is configured to include 1-bit information indicating activation or inactivation and a secondary cell ID. At this time, the mobile station apparatus 1 performs either activation or deactivation control on the instructed secondary cell ID.

Thus, according to the first embodiment, when the base station apparatus 2 is configured with a plurality of uplink frequencies (uplink component carriers) having different uplink transmission timings in the mobile station apparatus 1, Requests start of uplink transmission timing adjustment using two messages. Further, the mobile station device 1 activates the designated component carrier (cell) by the layer 2 message transmitted from the base station device 2 and at the same time determines whether or not random access has started, and if necessary, Start the random access procedure.

As described above, according to the present embodiment, it is possible to solve the problem that the method used in the conventional EUTRA cannot instruct the start of the random access procedure in the deactivated secondary cell. That is, according to this Embodiment, the problem that the mobile station apparatus 1 cannot start a random access procedure in cells other than a primary cell by a physical downlink control channel can be solved. Furthermore, since the base station apparatus 2 uses the L2 message used to activate the component carrier (cell) as a start command for the random access procedure, the L2 message can be reused without being extended. The activation of the component carrier (cell) is performed by the base station apparatus 2 at an appropriate timing for each mobile station apparatus 1 according to the buffer amount of the mobile station apparatus 1 and the QoS of the service. It is also possible to suppress the occurrence of unnecessary random access procedures.

<E. Second Embodiment>
A second embodiment of the present invention will be described below.

This embodiment shows a random access transmission method for starting a non-contention based random access procedure in a secondary cell using an L2 message. The configurations of mobile station apparatus 1 and base station apparatus 2 according to the present embodiment may be the same as those in FIG. 5 and FIG.

Also, the configuration of the cell (component carrier) set in the mobile station apparatus 1 and the uplink physical channel setting may be the same as in FIG.

FIG. 10 shows a method for causing the base station apparatus 2 according to the present embodiment to start a random access procedure in a secondary cell (or secondary cell group) having uplink transmission timing different from that of the primary cell of the mobile station apparatus 1. It is the sequence chart shown. In order to notify the mobile station apparatus 1 whether the uplink transmission timing is the same, the base station apparatus 2 sets a transmission timing group ID (TA group ID) indicating the same uplink transmission timing when adding a secondary cell. It may be configured to set. The sequence chart relating to the addition of the secondary cell up to FIG. 10 is the same as FIG.

When the TA group ID notified when the secondary cell is added is different from the held TA group ID, the mobile station apparatus 1 determines that the uplink transmission timing of the added secondary cell is different. The TA group ID value including the primary cell is configured such that a fixed value (for example, “0”) is assigned so that the mobile station apparatus 1 is not notified until management of a plurality of uplink transmission timings becomes necessary. Also good.

The base station apparatus 2 notifies the mobile station apparatus 1 of the secondary cell activation command and the non-contention based Random Access designation information as a set, and requests the activation of the secondary cell (step S301). At this time, as a cell to be activated, a plurality of secondary cells may be designated at the same time. Moreover, you may comprise so that activation and inactivation may be designated simultaneously. Both the secondary cell activation command and the non-contention based Random Access designation information are typically notified by one L2 message. The secondary cell activation command and the non-contention based Random Access designation information are preferably indicated using MAC control elements. Even if the base station device 2 transmits the secondary cell activation command and the non-contention based Random Access designation information in the primary cell of the mobile station device 1, the base station device 2 transmits the command in any secondary cell that has already been activated. Also good.

The base station apparatus 2 transmits the dedicated preamble number and the random access channel number to be used by including at least Non-contention based Random Access designation information.

The mobile station device 1 instructed by the base station device 2 to activate a secondary cell having a different uplink transmission timing activates the secondary cell and uses the notified non-contention based random access designation information The Non-contention based Random Access procedure is started (step S302). The non-contention based random access procedure may be the same as the procedure described in FIG. However, each step (step S11 to step S13) in the Non-contention based Random Access procedure at this time is transmitted / received in the uplink or downlink of the secondary cell.

The L2 message related to secondary cell activation transmitted in step S301 of FIG. 10 may be the same as the L2 message used for conventional secondary cell activation. Since the specific control method and the configuration of the included control commands have been described in the first embodiment, detailed description will not be repeated.

In addition, an L2 message related to the Non-contention based Random Access procedure transmitted in Step S301 in FIG. 10 includes an index number indicating that at least information necessary for the Non-contention based Random Access procedure is included, and Information indicating the number of the dedicated preamble and the random access channel number used in the Non-contention based Random Access procedure is set.

Here, when a plurality of secondary cells are activated at the same time by one secondary cell activation command, the cell in which the mobile station apparatus 1 starts the random access procedure is indicated in the Non-contention based Random Access designation information. The secondary cell ID may be included as information (may be added). Or, the base station apparatus 2 sets information necessary for the random access procedure only for one secondary cell among a plurality of secondary cells set with the same TA group ID, and Non-contention based Random Access designation information The TA group ID may be included (added) as information indicating a cell for starting the random access procedure. Thereby, when the base station apparatus 2 instructs the mobile station apparatus 1 to activate a plurality of secondary cells, the base station apparatus 2 causes the mobile station apparatus 1 to start the non-contention based Random Access procedure. A cell can be indicated.

In addition, when the base station apparatus 2 sets information necessary for the random access procedure only in one secondary cell having different uplink transmission timing, the secondary cell ID or TA group is set in the non-contention based Random Access designation information. It is not necessary to include an ID. Alternatively, the mobile station device 1 does not need to confirm the secondary cell ID or TA group ID included (added) in the non-contention based Random Access designation information.

In addition, when the mobile station apparatus 1 can execute only one random access procedure at the same time, the base station apparatus 2 includes non-contention based random access designation information for one cell in one secondary cell activation command. You may be made to do. At this time, the mobile station device 1 may be configured to ignore the received L2 message when the non-contention based Random Access designation information for a plurality of cells is included in one secondary cell activation command. Good. Alternatively, it may be configured to activate only the secondary cell without starting the random access procedure. Alternatively, the Non-contention based Random Access procedure may be started for any one cell.

When the mobile station device 1 can simultaneously execute a plurality of random access procedures, the base station device 2 makes sure that the secondary cell activation command includes non-contention based random access designation information for a plurality of cells. May be. At this time, the mobile station device 1 activates a plurality of designated secondary cells and starts a non-contention based random access procedure in each secondary cell designated with a non-contention based random access procedure.

FIG. 11 shows either of the Contention based Random Access procedure or the Non-contention based Random Access procedure when the mobile station device 1 according to the present embodiment activates a secondary cell having an uplink transmission timing different from that of the primary cell. 10 is an example of a flowchart used for determining whether to select a random access procedure.

The mobile station apparatus 1 determines whether a secondary cell activation command is received from the base station apparatus 2 using the L2 message (step S401). If the mobile station device 1 has not received the secondary cell activation command with the L2 message (No in step S401), the mobile station device 1 returns to step S401 and repeats the process. When the mobile station device 1 receives the secondary cell activation command using the L2 message (Yes in step S401), the mobile station device 1 proceeds to step S402. In step S402, the mobile station apparatus 1 is a case where activation of a secondary cell at an uplink transmission timing different from that of the primary cell is requested, and there is a random access setting corresponding to the uplink of the secondary cell. Determine whether or not. If the above condition is not satisfied (No in step S402), the random access procedure is unnecessary and the process is completed. In step S402, the mobile station device 1 is a case where activation of a secondary cell having an uplink transmission timing different from that of the primary cell is requested, and there is a random access setting corresponding to the uplink of the secondary cell, In addition, when the transmission timing is not adjusted, it may be determined that the above condition is satisfied.

Moreover, the mobile station apparatus 1 is a case where activation of a secondary cell is requested | required in step S402, Comprising: The random access setting corresponding to the uplink of the said secondary cell exists, and it is a transmission timing non-adjustment state. Sometimes, it may be determined that the above condition is satisfied.

On the other hand, if the above condition is satisfied (Yes in step S402), the process proceeds to step S403. In step S403, the mobile station apparatus 1 determines whether a non-contention based Random Access procedure is requested. If the secondary cell is activated and the non-contention based random access designation information is notified in the L2 message and the number of the individual preamble included in the non-contention based random access designation information is not 0, the mobile station device 1 determines that the Non-contention based Random Access procedure is required, and implements the Non-contention based Random Access procedure (step S404). The process is then complete.

When only the activation of the secondary cell is specified in the L2 message, or when the number of the individual preamble included in the Non-contention based Random Access specification information is 0, the mobile station device 1 reads the Contention based It is determined that Random Access is requested, and the contention based Random Access procedure is performed (step S405). The process is then complete.

Thus, according to the second embodiment, when the base station apparatus 2 is configured with a plurality of uplink frequencies (uplink component carriers) having different uplink transmission timings in the mobile station apparatus 1, Request the start of uplink transmission timing adjustment using the Non-contention based Random Access procedure using 2 messages. In addition, the mobile station apparatus 1 activates the designated component carrier (cell) based on the layer 2 message transmitted from the base station apparatus 2 and at the same time determines whether or not the random access procedure is started, and is necessary. For example, one of the Contention based Random Access procedure and the Non-contention based Random Access procedure is selected and started.

As described above, in addition to the first embodiment, the mobile station apparatus 1 can perform the Non-contention based Random Access procedure, so that the random access collision probability is reduced, and the uplink component carrier ( The time required for activation of the cell is further shortened. The base station apparatus 2 comprehensively determines the utilization efficiency of radio resources, the load status of the own station and the mobile station apparatus 1, and the contention based random access procedure and non-contention based random access procedure for the mobile station apparatus 1. It is possible to specify either one of them, so that efficient scheduling can be performed.

In addition, the random access procedure performed simultaneously with the activation of the secondary cell may be limited to the non-contention based random access procedure. When only the secondary cell activation command is notified in the layer 2 message, the mobile station device 1 does not execute the random access procedure, but in the layer 2 message, the secondary cell activation command and the non-contention based random access designation information May be executed, a random access procedure may be executed. In this case, the mobile station apparatus 1 may execute the Contention based Random Access procedure only when the Non-contention based Random Access designation information indicates that the Contention based Random Access procedure is to be executed. For example, the mobile station device 1 performs the contention based random access procedure instead of the non-contention based random access procedure only when the value of the preamble number included in the non-contention based random access specification information is “0”. May be.

<F. Other Embodiments>
The embodiment described above is merely an example, and can be realized using various modifications and replacement examples. For example, as an uplink transmission method, it can be applied to both communication systems of an FDD (frequency division duplex) scheme and a TDD (time division duplex) scheme. In each embodiment, an example using a path loss as a measurement value of a downlink component carrier has been described. However, other measurement values (SIR, SINR, RSRP, RSRQ, RSSI, BLER) may be used instead. It is also possible to use a combination of a plurality of these measured values.

Further, for convenience of explanation, the mobile station device 1 and the base station device 2 of the embodiment have been described using functional block diagrams. However, the functions of each part of the mobile station device 1 and the base station device 2 or one of these functions The mobile station device 1 and the base station device 2 are controlled by recording a program for realizing the unit on a computer-readable recording medium, causing the computer system to read and execute the program recorded on the recording medium. You may go. Here, the “computer system” includes an OS and hardware such as peripheral devices.

The “computer-readable recording medium” refers to a semiconductor medium (eg, RAM, nonvolatile memory card, etc.), an optical recording medium (eg, DVD, MO, MD, CD, BD, etc.), a magnetic recording medium (eg, , A magnetic tape, a flexible disk, etc.) and a storage device such as a disk unit built in a computer system. Furthermore, the “computer-readable recording medium” means that a program is dynamically held for a short time, like a communication line when a program is transmitted via a network such as the Internet or a communication line such as a telephone line. In this case, it is intended to include those that hold a program for a certain period of time, such as a volatile memory inside a computer system serving as a server or a client in that case. Further, the program may be for realizing a part of the above-described functions, and may be capable of realizing the above-described functions in combination with a program already recorded in the computer system. .

In addition, each functional block or various features of the mobile station apparatus 1 and the base station apparatus 2 used in the above embodiments is typically in a circuit including an LSI (Large Scale Integration) which is an IC (Integrated Circuit). It may be configured. In that case, the integration density of the LSI may be realized at any density. Each functional block and various features may be individually chipped, or a part or all of them may be integrated into a chip. Further, the method of circuit integration is not limited to LSI, and may be realized by a dedicated circuit or a general-purpose processor. In addition, when an integrated circuit technology that replaces LSI appears due to progress in semiconductor technology, an integrated circuit based on the technology can also be used.

The present invention includes the following embodiments.
(1) In a communication system according to an embodiment, a base station device and a mobile station device are connected simultaneously with a plurality of serving cells to perform communication. The plurality of serving cells are configured of a first serving cell that is not deactivated and one or more second serving cells that are activated or deactivated. When the base station apparatus sets information necessary for the random access procedure in the first serving cell and the second serving cell, the base station apparatus activates the second serving cell in which information necessary for the random access procedure is set. The mobile station device requests the mobile station device to start a random access procedure. When the second serving cell in which information necessary for the random access procedure is set is activated, the mobile station device activates the random access procedure. To start.

(2) In the communication system according to the present embodiment, the base station apparatus activates the second serving cell in which information necessary for the random access procedure is set and transmits control information necessary for non-contention based random access. By notifying, the mobile station apparatus is requested to start a non-contention based random access procedure.

(3) In the communication system according to the present embodiment, the mobile station apparatus activates the second serving cell in which information necessary for the random access procedure is set and controls information necessary for non-contention based random access In response to the notification, a non-contention based random access procedure is started using the control information.

(4) In the communication system according to the present embodiment, activation of the second serving cell is notified by an L2 message.

(5) A base station apparatus according to another embodiment is directed to a communication system in which a base station apparatus and a mobile station apparatus are connected simultaneously to a plurality of serving cells to perform communication. When the base station apparatus sets the information necessary for the random access procedure in the first serving cell that is not deactivated and one or more second serving cells that are activated or deactivated, the base station apparatus performs random access. The mobile station apparatus is requested to start a random access procedure by activating the second serving cell in which information necessary for the procedure is set.

(6) The base station apparatus according to the present embodiment activates the second serving cell in which information necessary for the random access procedure is set and notifies the control information necessary for non-contention based random access. Request the mobile station device to start a non-contention based random random access procedure.

(7) The base station apparatus according to the present embodiment notifies the activation of the second serving cell with an L2 message.

(8) A mobile station apparatus according to still another embodiment is directed to a communication system in which a base station apparatus and a mobile station apparatus are connected and communicated simultaneously with a plurality of serving cells. The mobile station apparatus is set to the first serving cell that is not deactivated and one or more second served cells that are activated or deactivated, from the base station apparatus, the information necessary for the random access procedure If the second serving cell in which information necessary for the random access procedure is set is activated, the random access procedure is started.

(9) The mobile station apparatus according to the present embodiment is notified of control information necessary for non-contention based random access while the second serving cell in which information necessary for the random access procedure is set is activated In this case, a non-contention based random access procedure is started using the control information.

(10) A random access transmission method for a mobile station apparatus according to still another embodiment is directed to a mobile station apparatus of a communication system in which a base station apparatus and a mobile station apparatus are connected and communicated simultaneously with a plurality of serving cells. It is done. The plurality of serving cells are configured of a first serving cell that is not deactivated and one or more second serving cells that are activated or deactivated. When the base station apparatus sets information necessary for the random access procedure in the first serving cell and the second serving cell, the base station apparatus activates the second serving cell in which information necessary for the random access procedure is set. Requesting the mobile station device to start a random access procedure by enabling the mobile station device to perform random access when the second serving cell in which information necessary for the random access procedure is set is activated. Including the step of initiating an access procedure.

(11) An integrated circuit of a mobile station apparatus according to still another embodiment performs random access of a mobile station apparatus in a communication system in which a base station apparatus and a mobile station apparatus are connected simultaneously to a plurality of serving cells to perform communication. Do. When the integrated circuit is set in the first serving cell that is not deactivated and the one or more second serving cells that are activated or deactivated, information necessary for the random access procedure from the base station apparatus When the second serving cell in which information necessary for the random access procedure is set is activated, the random access procedure is started.

As described above, the embodiments of the present invention have been described in detail based on specific specific examples. However, it is obvious that the gist and claims of the present invention are not limited to these specific specific examples. That is, the description in the present specification is for illustrative purposes and does not limit the present invention.

The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1 mobile station device, 2 base station device, 11-13 transmitting device, 21-23 receiving device, 101, 201 receiving unit, 102, 202 demodulating unit, 103, 203 decoding unit, 104 measurement processing unit, 105, 204 control unit 106, random access control unit, 107, 205 encoding unit, 108, 206 modulation unit, 109, 207 transmission unit, 110 timing management unit, 111, 208 upper layer, 209 network signal transmission / reception unit.

Claims

A communication system in which a base station apparatus and a mobile station apparatus perform communication by aggregating a plurality of serving cells,
The in-zone cell includes an inactivated state indicating a state not used for communication and an activated state indicating a state used for communication, and the aggregated in-zone cells are not inactivated. And a second serving cell to be activated or deactivated, and
When the base station apparatus sets information necessary for the random access procedure in the first serving cell and the second serving cell, the second information in which the information necessary for the random access procedure is set Requesting the mobile station device to start a random access procedure in the second serving cell by activating the serving cell;
When the second serving cell in which information necessary for the random access procedure is set by the base station device is activated, the mobile station device performs the random access procedure in the second serving cell. Starting a communication system.
The base station device activates the second serving cell in which information necessary for the random access procedure is set and notifies control information necessary for non-contention based random access, thereby allowing the mobile station to The communication system according to claim 1, wherein a device is requested to start a non-contention based random access procedure in the second serving cell.
The base station device
When requesting the mobile station apparatus to start a non-contention based random access procedure in the second serving cell in which information necessary for the random access procedure is set, the second serving cell is Activate and notify the control information necessary for non-contention based random access,
When requesting the mobile station apparatus to start a contention-based random access procedure in the second serving cell, the second presence information is not notified without notifying control information necessary for non-contention based random access. The communication system according to claim 1, wherein the communication cell is activated.
The mobile station apparatus is notified of control information necessary for non-contention based random access while the second serving cell in which information necessary for the random access procedure is set is activated from the base station apparatus. 3. The communication system according to claim 2, wherein a non-contention based random access procedure is started using the control information in the second serving cell.
The mobile station device
When the second serving cell in which information necessary for the random access procedure is set by the base station device is activated and control information necessary for non-contention based random access is notified, Initiating a non-contention based random access procedure using the control information in two serving cells;
The contention based random access procedure is started in the second serving cell when the second serving cell is activated and control information required for non-contention based random access is not notified. 2. The communication system according to 2.
The communication system according to any one of claims 1 to 5, wherein the activation of the second serving cell is notified by an L2 message.
A base station apparatus of a communication system in which a base station apparatus and a mobile station apparatus are connected simultaneously to a plurality of serving cells to perform communication, and the serving cell is in an inactive state indicating a state not used for communication And an activated state indicating a state used for communication, the base station device,
When the information necessary for the random access procedure is set in each of the first serving cell that is not deactivated and one or more second serving cells that are activated or deactivated, the random access procedure includes A base station apparatus that requests the mobile station apparatus to start a random access procedure in the second serving cell by activating the second serving cell in which necessary information is set.
Activating the second serving cell in which information necessary for the random access procedure is set and notifying control information necessary for non-contention based random access to the mobile station device The base station apparatus of Claim 7 which requests | requires the start of the non-contention based random access procedure in a serving cell.
When requesting the mobile station apparatus to start a non-contention based random access procedure in the second serving cell in which information necessary for the random access procedure is set, the second serving cell is Activate and notify the control information necessary for non-contention based random access,
When requesting the mobile station apparatus to start a contention-based random access procedure in the second serving cell, the second presence information is not notified without notifying control information necessary for non-contention based random access. The base station apparatus according to claim 7, wherein the base cell is activated.
The base station apparatus according to any one of claims 7 to 9, wherein activation of the second serving cell is notified by an L2 message.
A base station apparatus of a communication system in which a base station apparatus and a mobile station apparatus are connected simultaneously to a plurality of serving cells to perform communication, and the serving cell is in an inactive state indicating a state not used for communication And an activated state indicating a state used for communication, the base station device,
When the information necessary for the random access procedure is set in each of the first serving cell that is not deactivated and one or more second serving cells that are activated or deactivated, the mobile station apparatus A base station apparatus that activates the second serving cell in which information necessary for the random access procedure is set before starting a random access procedure in the second serving cell.
A mobile station apparatus of a communication system in which a base station apparatus and a mobile station apparatus are connected simultaneously to a plurality of serving cells to perform communication,
When the information necessary for the random access procedure is set from the base station apparatus to the first in-zone cell that is not deactivated and one or more second in-zone cells that are activated or deactivated The mobile station apparatus starts the random access procedure in the second serving cell when the second serving cell in which information necessary for the random access procedure is set is activated.
In the second serving cell when the second serving cell in which information necessary for the random access procedure is set is activated and control information necessary for non-contention based random access is notified The mobile station apparatus according to claim 12, wherein a non-contention based random access procedure is started using the control information.
When the second serving cell in which information necessary for the random access procedure is set is activated by the base station apparatus and control information necessary for non-contention based random access is notified, Start a non-contention based random access procedure with the control information in the serving cell of
The contention based random access procedure is started in the second serving cell when the second serving cell is activated and control information required for non-contention based random access is not notified. 12. The mobile station apparatus according to 12.
A random access transmission method in a mobile station device of a communication system in which a base station device and a mobile station device are connected simultaneously to a plurality of serving cells to perform communication, and the serving cell indicates a state not used for communication A plurality of aggregated serving cells including a deactivated state and an activated state indicating a state used for communication, wherein the aggregated serving cells include a first serving cell that is not deactivated and one or more activated or A second serving cell to be deactivated,
When the base station apparatus sets information necessary for the random access procedure in the first serving cell and the second serving cell, the second information in which the information necessary for the random access procedure is set Requesting the mobile station device to start a random access procedure in the second serving cell by activating the serving cell;
The mobile station apparatus starting the random access procedure in the second serving cell when the second serving cell in which information necessary for the random access procedure is set is activated; A random access transmission method comprising:
An integrated circuit that performs random access of a mobile station device in a communication system in which a base station device and a mobile station device are connected to perform communication simultaneously with a plurality of serving cells, and the serving cell is not used for communication And an inactive state indicating a state used for communication, and the integrated circuit includes:
When the information necessary for the random access procedure is set from the base station apparatus to the first in-zone cell that is not deactivated and one or more second in-zone cells that are activated or deactivated An integrated circuit that starts the random access procedure in the second serving cell when the second serving cell in which information necessary for the random access procedure is set is activated.