WO2012111596A1

WO2012111596A1 - Communication system, base station device, mobile station device, method for reporting power headroom, and integrated circuit

Info

Publication number: WO2012111596A1
Application number: PCT/JP2012/053238
Authority: WO
Inventors: 克成上村; 恭之加藤
Original assignee: シャープ株式会社
Priority date: 2011-02-15
Filing date: 2012-02-13
Publication date: 2012-08-23
Also published as: JP2012169913A

Abstract

Provided is a communication system that reports, to a base station device, the power headroom indicating the transmission power reserve of a plurality of serving cells to which a mobile station device is connected. The plurality of serving cells include: a first serving cell having the same uplink transmission timing as a primary cell; and a second serving cell that is activated or deactivated and that has an uplink transmission timing different from the first serving cell. The base station device activates the second serving cell that has been set to the mobile station device. When the uplink transmission timing of the second serving cell, which has been activated by the base station device, enters an adjustment state on the basis of transmission-timing adjustment information related to the second serving cell and received from the base station device, the mobile station device determines that the condition for triggering the reporting of the power headroom has been satisfied.

Description

Communication system, base station apparatus, mobile station apparatus, power headroom reporting method, and integrated circuit

The present invention provides a communication system in which a mobile station apparatus efficiently reports power headroom when a plurality of uplink transmission timing adjustments are required, a base station apparatus and a mobile station apparatus directed to the communication system, The present invention relates to a power headroom reporting method and an integrated circuit.

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

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. Further, it has been proposed that a mobile station apparatus communicating with a base station apparatus has a plurality of uplink transmission timings (Timing Advance) for each frequency or component carrier using carrier aggregation (Non-patent Document). 1).

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 apparatus autonomously determines the necessity of the random access procedure and starts access, the base station apparatus causes the specific mobile station apparatus to start the random access procedure. There is a method in which information indicating the start of a random access procedure is set in the physical downlink control channel and transmitted.

In 3GPP, a power headroom (hereinafter also referred to as “PHR”) for notifying the base station device of the remaining power of the transmission power of the mobile station device is used. The PHR is obtained by subtracting the transmission power required for the physical uplink shared channel or the transmission power required for the physical uplink shared channel and the physical uplink control channel from the maximum transmission power of the mobile station apparatus in a certain component carrier. It represents the remaining power (remaining power of transmission power). A larger PHR indicates that there is a margin in uplink transmission of the mobile station apparatus that is the report source. The base station apparatus may execute appropriate scheduling such as designating a modulation scheme with a high transmission rate and allocating more resources to the reporting mobile station apparatus with reference to the reported PHR. it can. Non-Patent Document 2 describes a conventional PHR calculation method.

In addition, the base station apparatus configures one cell by combining one downlink component carrier and one uplink component carrier. Note that the base station apparatus can configure one cell with only one downlink component carrier.

However, the newly added component carrier cell is in an inactive state (details will be described later) in which data transmission / reception and physical downlink control channel monitoring are not performed. Further, as proposed in Non-Patent Document 1, the transmission timing has a plurality of uplink transmission timings, and each uplink transmission timing is set for each uplink component carrier (or uplink component carrier group and / or uplink frequency). When the component carrier is activated, there is a component carrier that cannot be transmitted because the uplink transmission timing is not adjusted. This means that even if the mobile station apparatus reports PHR of a component carrier that cannot be transmitted, the base station apparatus cannot perform scheduling using the component carrier.

Therefore, when a component carrier having a plurality of uplink transmission timings is set, a specific solution for the problem that the mobile station device reports the PHR of the component carrier that cannot be scheduled by the base station device is Non-Patent Document 1 and Non-Patent Document 2 do not show anything.

In view of the above problems, an object of the present invention is directed to a communication system that enables efficient power headroom reporting by a mobile station apparatus when adjustment of a plurality of uplink transmission timings is necessary. A base station apparatus and a mobile station apparatus, a power headroom reporting method, and an integrated circuit.

According to an embodiment of the present invention, there is provided a communication system that reports power headroom indicating the remaining power of transmission power of a plurality of serving cells to which a mobile station apparatus is connected to a base station apparatus. The plurality of serving cells have a first serving cell having the same uplink transmission timing as the primary cell and an uplink transmission timing different from the first serving cell, and are activated or deactivated. Second serving cell. The base station device activates the second serving cell set in the mobile station device. In the mobile station device, the uplink transmission timing of the second serving cell activated by the base station device has been adjusted based on the transmission timing adjustment information related to the second serving cell received from the base station device. Sometimes it is determined that the power headroom reporting trigger condition has been met.

In the communication system according to the present embodiment, the base station device notifies the transmission timing adjustment information using the Contention based Random Access procedure.

In the communication system according to the present embodiment, the base station apparatus notifies transmission timing adjustment information using a non-contention based Random Access procedure.

In the communication system according to the present embodiment, when the mobile station apparatus determines that the trigger condition for power headroom reporting is satisfied, the mobile station apparatus activates a plurality of serving cells and adjusts the uplink transmission timing. Based on the above, the serving cell reporting the power headroom is determined.

In the communication system according to the present embodiment, the mobile station apparatus reports to the base station apparatus the power headroom of the second serving cell in which the mobile station apparatus is activated and the uplink transmission timing is adjusted.

According to another embodiment of the present invention, there is provided a communication system for reporting to a base station device a power headroom indicating the remaining power of transmission power of a plurality of serving cells connected to the mobile station device. The plurality of serving cells have a first serving cell having the same uplink transmission timing as the primary cell and an uplink transmission timing different from the first serving cell, and are activated or deactivated. Second serving cell. The base station device activates the second serving cell set in the mobile station device. The mobile station apparatus executes the random access procedure in the second serving cell activated by the base station apparatus, and whether or not the trigger condition for power headroom reporting is satisfied based on the success or failure of the random access procedure Determine whether.

In the communication system according to the present embodiment, the random access procedure is the Contention based Random Access procedure, and the mobile station apparatus determines whether the trigger condition of the power headroom is based on whether or not the contention resolution is correctly received. Determine if it is satisfied.

In the communication system according to the present embodiment, the random access procedure is a Non-contention based Random Access procedure, and the mobile station apparatus determines whether the power headroom trigger condition is based on whether or not the random access response is correctly received. Determine if it is satisfied.

According to still another embodiment of the present invention, there is provided a mobile station apparatus in a communication system that reports to a base station apparatus a power headroom indicating the remaining power of transmission power of a plurality of serving cells to which the mobile station apparatus is connected. Is done. The plurality of serving cells have a first serving cell having the same uplink transmission timing as the primary cell and an uplink transmission timing different from the first serving cell, and are activated or deactivated. Second serving cell. In the mobile station device, the uplink transmission timing of the second serving cell activated by the base station device has been adjusted based on the transmission timing adjustment information related to the second serving cell received from the base station device. Sometimes it is determined that the power headroom reporting trigger condition has been met.

The mobile station apparatus according to the present embodiment receives transmission timing adjustment information from the base station apparatus using a Contention based Random Access procedure.

The mobile station apparatus according to the present embodiment receives transmission timing adjustment information from the base station apparatus using a non-contention based Random Access procedure.

When it is determined that the power headroom report trigger condition is satisfied, the mobile station apparatus according to the present embodiment is based on the activation state of a plurality of serving cells and the uplink transmission timing adjustment state. Determine the serving cell reporting power headroom.

The mobile station apparatus according to the present embodiment reports to the base station apparatus the power headroom of the second serving cell that is activated and whose uplink transmission timing is in an adjusted state.

According to still another embodiment of the present invention, there is provided a mobile station apparatus in a communication system that reports to a base station apparatus a power headroom indicating the remaining power of transmission power of a plurality of serving cells to which the mobile station apparatus is connected. Is done. The plurality of serving cells have a first serving cell having the same uplink transmission timing as the primary cell and an uplink transmission timing different from the first serving cell, and are activated or deactivated. Second serving cell. The mobile station apparatus executes the random access procedure in the second serving cell activated by the base station apparatus, and whether or not the trigger condition for power headroom reporting is satisfied based on the success or failure of the random access procedure Determine whether.

When the random access procedure is the Contention based Random Access procedure, the mobile station apparatus according to this embodiment determines whether the power headroom trigger condition is satisfied based on whether the contention resolution is correctly received. Determine whether.

When the random access procedure is a non-contention based random access procedure, the mobile station apparatus according to the present embodiment determines whether the power headroom trigger condition is satisfied based on whether the random access response is correctly received. Determine whether.

According to still another embodiment of the present invention, there is provided a base station apparatus in a communication system that reports to a base station apparatus a power headroom indicating the remaining power of transmission power of a plurality of serving cells to which the mobile station apparatus is connected. Is done. The plurality of serving cells have a first serving cell having the same uplink transmission timing as the primary cell and an uplink transmission timing different from the first serving cell, and are activated or deactivated. Second serving cell. The base station device activates the second serving cell set in the mobile station device, transmits transmission timing adjustment information related to the activated second serving cell to the mobile station device, and sets the second serving cell of the second serving cell. By setting the uplink transmission timing to the adjusted state, the mobile station apparatus is caused to determine that the trigger condition for reporting the power headroom is satisfied.

According to still another embodiment of the present invention, there is provided a base station apparatus in a communication system that reports to a base station apparatus a power headroom indicating the remaining power of transmission power of a plurality of serving cells to which the mobile station apparatus is connected. Is done. The plurality of serving cells have a first serving cell having the same uplink transmission timing as the primary cell and an uplink transmission timing different from the first serving cell, and are activated or deactivated. Second serving cell. The base station apparatus activates the second serving cell set in the mobile station apparatus and causes the mobile station apparatus to execute a random access procedure for the activated second serving cell, thereby causing the mobile station apparatus to perform random access. Based on the success or failure of the access procedure, it is determined whether the trigger condition for power headroom reporting has been met.

According to still another embodiment of the present invention, a power headroom reporting method in a communication system for reporting to a base station device a power headroom indicating the remaining power of transmission power of a plurality of serving cells to which the mobile station device is connected. Is provided. The plurality of serving cells have a first serving cell having the same uplink transmission timing as the primary cell and an uplink transmission timing different from the first serving cell, and are activated or deactivated. Second serving cell. The base station device activates the second serving cell set in the mobile station device. In the mobile station device, the uplink transmission timing of the second serving cell activated by the base station device has been adjusted based on the transmission timing adjustment information related to the second serving cell received from the base station device. Sometimes it is determined that the power headroom reporting trigger condition has been met.

According to still another embodiment of the present invention, a power headroom reporting method in a communication system for reporting to a base station device a power headroom indicating the remaining power of transmission power of a plurality of serving cells to which the mobile station device is connected. Is provided. The plurality of serving cells have a first serving cell having the same uplink transmission timing as the primary cell and an uplink transmission timing different from the first serving cell, and are activated or deactivated. Second serving cell. The base station device activates the second serving cell set in the mobile station device. The mobile station apparatus executes the random access procedure in the second serving cell activated by the base station apparatus, and whether or not the trigger condition for power headroom reporting is satisfied based on the success or failure of the random access procedure Determine whether.

According to still another embodiment of the present invention, a mobile station apparatus in a communication system that reports to a base station apparatus a power headroom indicating the remaining transmission power of a plurality of serving cells connected to the mobile station apparatus. An integrated circuit is provided. The plurality of serving cells have a first serving cell having the same uplink transmission timing as the primary cell and an uplink transmission timing different from the first serving cell, and are activated or deactivated. Second serving cell. In the integrated circuit, when the uplink transmission timing of the second serving cell activated by the base station apparatus is in an adjustment state based on the transmission timing adjustment information regarding the second serving cell received from the base station apparatus And the power headroom reporting trigger condition is satisfied.

According to still another embodiment of the present invention, a mobile station apparatus in a communication system that reports to a base station apparatus a power headroom indicating the remaining transmission power of a plurality of serving cells connected to the mobile station apparatus. An integrated circuit is provided. The plurality of serving cells have a first serving cell having the same uplink transmission timing as the primary cell and an uplink transmission timing different from the first serving cell, and are activated or deactivated. Second serving cell. The integrated circuit performs a random access procedure in the second serving cell activated by the base station apparatus, and whether or not a trigger condition for power headroom reporting is satisfied based on the success or failure of the random access procedure Judging.

In the present specification, the present invention is intended to improve a communication system, a base station apparatus, a mobile station apparatus, a power headroom reporting method, and an integrated circuit when a mobile station apparatus and a base station apparatus are connected using a plurality of frequencies simultaneously. Although the invention is disclosed, a communication system to which the present invention is applicable is not limited to a communication system 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 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 power It is possible to provide a communication system capable of reporting headroom, a base station apparatus and mobile station apparatus directed to the communication system, a power headroom reporting method, and an integrated circuit.

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 which concerns on 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 which concerns on embodiment of this invention. It is a block diagram which shows the example of schematic structure of the mobile station apparatus which concerns on the 1st Embodiment of this invention. It is a block diagram which shows the example of schematic structure of the base station apparatus which concerns on the 1st Embodiment of this invention. It is a figure for demonstrating the transmission possible timing of PHR which concerns on the 1st Embodiment of this invention. It is a sequence chart for demonstrating the procedure until it transmits PHR which concerns on the 1st Embodiment of this invention. It is a flowchart for demonstrating the procedure until it transmits PHR which concerns on the 1st Embodiment of this invention. It is a figure for demonstrating the transmission possible timing of PHR which concerns on the 2nd Embodiment of this invention. It is a sequence chart for demonstrating the procedure until it transmits PHR which concerns on the 2nd Embodiment of this invention. It is another sequence chart for demonstrating the procedure until it transmits PHR which concerns on the 2nd Embodiment of this invention.

A brief description of carrier aggregation, physical channels, random access procedures, and power headroom reporting associated with embodiments of the present invention is provided.

[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 transmitted in the 800 MHz band, another component carrier is transmitted in the 2 GHz band, and another component carrier is transmitted in the 3.4 GHz band. May be.

Also, it is possible to aggregate a plurality of 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, and the frequency bandwidth may be different from each other. The base station apparatus determines the number of uplink or downlink component carriers to be allocated 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 the QoS. You can increase or decrease the number. Note that the number of uplink component carriers assigned by the base station apparatus is preferably equal to or less than the number of downlink component carriers.

[Physical channel]
Next, 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. The physical channel may be added or changed in the future in EUTRA and / or Advanced EUTRA, but even if it is changed, the content of the embodiment according to the present invention is not affected.

In EUTRA and Advanced EUTRA, physical channel scheduling is managed using radio frames. One radio frame is 10 ms, and one radio frame is composed of 10 subframes. Further, one subframe is composed of two slots (that is, one slot is 0.5 ms). Also, management is performed using resource blocks as the minimum scheduling unit in which physical channels are arranged. The resource block is defined by a constant frequency region composed of a set of a plurality of subcarriers (for example, 12 subcarriers) and a time region composed of a constant transmission time interval (1 slot).

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. A 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 device identifies the cell ID of the received synchronization signal by 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 in mobile station apparatuses in the cell. Broadcast information that is not notified in the physical broadcast information channel is transmitted in a layer 3 message (system information) through the physical downlink shared channel after the radio resource used for transmission is notified in the physical downlink control channel. As broadcast information, a cell global identifier (CGI; Cell Global Identifier) indicating a cell-specific identifier, a tracking area identifier (TAI; Tracking Area Identifier) for managing a paging standby area, 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 a time position according to 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 simultaneous demodulation of the physical downlink control channel or the physical downlink shared channel that is 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 a cell-specific RS (Cell-specific reference signals), but its use and meaning are the same.

A physical downlink control channel (PDCCH; Physical Downlink Control Channel) is transmitted in several OFDM symbols from the top of each subframe, and radio resource allocation information according to the scheduling of the base station apparatus is transmitted to the mobile station apparatus. It is used for the purpose of instructing the adjustment amount of increase / decrease of transmission power. The mobile station apparatus monitors (monitors) the physical downlink control channel addressed to itself before transmitting / receiving downlink data or layer 3 messages (paging, handover command, etc.) that are downlink control data. Receiving the physical downlink control channel addressed to the station, it is necessary to acquire from the physical downlink control channel each radio resource allocation information called uplink grant during transmission and downlink grant (downlink assignment) during reception There is.

The physical uplink control channel (PUCCH; Physical Uplink Control Channel) includes a data acknowledgment confirmation (ACK / NACK: Acknowledgement / Negative Acknowledgement) and downlink propagation path information C (QQn): Q I It is used to notify a quality request (SR: Scheduling Request) that is an uplink radio resource request.

The physical downlink shared channel (PDSCH; Physical Downlink Shared Channel) notifies the mobile station apparatus of not only downlink data but also broadcast information not included in the physical broadcast information channel as a layer 3 message that is downlink control data. Also used to do. 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, but can also include control data such as downlink reception quality and ACK / NACK. is there. Similarly to the physical downlink shared channel, the radio resource allocation information of the physical uplink shared channel is indicated by the physical downlink control channel.

An uplink reference signal (uplink reference signal: Uplink Reference Signal; also referred to as an uplink pilot signal or an uplink pilot channel) includes a demodulation reference signal (DRS: Demodulation Reference Signal) and a sounding reference signal (SRS: Sounding Reference Signal). ). The demodulation reference signal is used by the base station apparatus to demodulate the physical uplink control channel PUCCH and / or the physical uplink shared channel PUSCH. The sounding reference signal is mainly used by the base station apparatus to estimate the uplink channel state.

A physical random access channel (PRACH) is a channel used for notifying a preamble sequence and has a guard time. The preamble sequence is configured to represent 6-bit information by preparing 64 types of sequences. The physical random access channel is used as an access means from the mobile station apparatus to the base station apparatus. The mobile station device uses the physical random access channel to request radio resources from the base station device when the physical uplink control channel is not set, or to match the uplink transmission timing with the reception timing window of the base station device. Request transmission timing adjustment information (also referred to as timing advance (TA)) to 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. When the mobile station device receives the transmission timing adjustment information, the mobile station device sets a transmission timing timer (TA timer) that measures the effective time of the transmission timing adjustment information, sets the transmission timing adjustment state during the effective time, and transmits the transmission timing outside the effective period The state is managed as an unadjusted state (transmission timing unadjusted state). The other physical channels are not directly related to the embodiment of the present invention, and thus will not be described in detail.

[Random access procedure]
In this specification, a series of procedures relating to random access is referred to as a random access procedure. The random access procedure includes a contention based random access (contention based random access) procedure and a non-contention based random access (non-contention based random access) procedure.

The Contention based Random Access procedure is a random access procedure in which preamble sequences transmitted by different mobile station apparatuses may collide. The Contention based Random Access procedure is typically used for initial access from a state in which the mobile station device is not connected (communication) to the base station device or from a state in which the mobile station device is connected to the base station device. This is used for a scheduling request for requesting uplink transmission resources. The collision of preamble sequences means that a plurality of mobile station apparatuses use the same preamble sequence and transmit physical random access channels using the same frequency and time resources. 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 apparatuses. The non-contention based Random Access procedure is typically a state in which the mobile station device is connected (communication) with the base station device and the uplink is out of synchronization. Is started. The start of 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 randomly selected by the mobile station apparatus from the preamble sequences that are not used as individual preambles 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 the Contention based Random Access procedure and the Non-contention based Random Access procedure is notified from the base station apparatus.

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

The mobile station apparatus 1 confirms the content of the random access response, and when the random access response includes a preamble number corresponding to the transmitted random access preamble, the mobile station apparatus 1 determines the uplink transmission timing based on the transmission timing adjustment information. adjust. When adjusting the transmission timing, the mobile station apparatus 1 starts a transmission timing timer (TA timer) in which the adjusted transmission timing is valid. Also, the mobile station apparatus 1 transmits an upper layer message (upper layer message and / or RRC message) to the base station apparatus 2 in accordance with the scheduling information included in the random access response (step S3). The base station apparatus 2 transmits a collision confirmation message (contention resolution, contention resolution) to the mobile station apparatus 1 that has received the upper layer message of step S3 (step S4). This completes the procedure.

Next, a 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 in which transmission of an individual preamble with a number notified from the base station apparatus 2 to the mobile station apparatus 1 is permitted. For example, one random access channel number indicates that a dedicated preamble may be transmitted on all physical random access channels, and another random access channel number indicates a dedicated preamble on every second physical random access channel in the time direction. Indicates that it may be sent. The mobile station apparatus 1 transmits a preamble sequence (individual preamble) corresponding to the designated number on the physical random access channel indicated by the random access channel number and permitted to transmit the dedicated preamble (step S12). . When the base station apparatus 2 receives the dedicated preamble, the base station apparatus 2 calculates a transmission timing shift amount between the mobile station apparatus 1 and the base station apparatus 2 from the dedicated preamble, and transmits a response to the dedicated preamble (random access response) as a transmission timing. The transmission timing adjustment information for adjusting the deviation is transmitted to the mobile station apparatus 1 (step S13). This completes the procedure.

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.

[Power Headroom Report]
The power headroom is calculated by the mobile station device for each frequency (component carrier and / or cell) and notified to the base station device. In the mobile station apparatus, the power headroom is calculated in the physical layer (layer 1) based on parameters set from the RRC layer and managed in the MAC layer. The physical layer notifies the MAC layer of the calculated power headroom value of each component carrier.

The MAC layer of the mobile station apparatus determines that it is the power headroom reporting timing when any of the following trigger conditions is satisfied, and uses the MAC control element included in the control header portion of the data to determine the PHR. Is transmitted to the base station apparatus. The trigger condition is (1) when the PHR report prohibition timer (Prohibit PHR timer) is stopped, and when the path loss value of the serving cell is deteriorated by a predetermined value or more than when the previous PHR was reported, (2 ) When the PHR period timer expires, (3) when the PHR setting is changed, and (4) when the secondary cell is activated.

In Advanced ETURA, two types of reporting formats are defined as PHR.

The first report format (type 1) is a report format applied when only the physical uplink shared channel PUSCH can be transmitted in a subframe in which the mobile station apparatus is present. Type 1 PHR uses different PHR calculation methods for subframes transmitting PUSCH and subframes not transmitting PUSCH. This detailed calculation method follows the description of 3GPP TS36.213.

The second report format (type 2) is a report format applied when the physical uplink control channel PUCCH and the physical uplink shared channel PUSCH can be transmitted simultaneously in a subframe in which the mobile station apparatus is present. Type 2 PHR uses different PHR calculation methods for subframes transmitting PUCCH and PUSCH simultaneously, subframes transmitting only PUSCH, and subframes transmitting only PUCCH. . This detailed calculation method follows the description of 3GPP TS36.213.

Based on the mobile station apparatus capability (UE capability) notified from the mobile station apparatus, the base station apparatus moves using a layer 3 message as to which of the type 1 and type 2 PHR report formats is to be used. Set for each station device.

[Example of communication network configuration of the present invention]
FIG. 3 is a diagram showing an example of a communication network configuration according to the embodiment of the present invention. The mobile station apparatus 1 can be wirelessly connected to the base station apparatus 2 by simultaneously using a plurality of frequencies (component carriers) Band1 to Band3 by carrier aggregation. In this case, as a communication network configuration, one base station apparatus 2 has transmitting apparatuses 11 to 13 (and receiving apparatuses 21 to 23 (not shown)) for a plurality of frequencies, and each frequency is controlled by one. A configuration performed by the base station apparatus 2 is preferable from the viewpoint of simplification of control. The configuration of the base station apparatus 2 is not limited to FIG. However, the base station device 2 may be configured to transmit a plurality of frequencies with a single transmission device because the plurality of frequencies are continuous frequencies. Furthermore, a configuration in which transmission / reception timing differs for each frequency may be employed. The number of transmitters and receivers and the frequency at which transmission and reception can be performed 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 the respective frequencies may have different widths and / or different shapes.

However, in the description to be described later, the areas covered by the frequency of the component carrier configured by the base station apparatus 2 are each referred to as a cell, and this is the definition of the cell in the actually operated communication system. Note that may 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. In the embodiment according to the present invention, even when a component carrier is referred to as a cell and a case where the component carrier is different from the definition of a cell in an actually operated communication system occurs, the gist of the present invention is not affected. Note that carrier aggregation is communication performed by a plurality of cells using a plurality of component carriers, and is also referred to as cell aggregation. The mobile station apparatus 1 may be wirelessly connected to the base station apparatus 2 via a relay station apparatus (or repeater) for each frequency. That is, the base station apparatus 2 in the embodiment according to the present invention 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 is communicable with a certain base station device 2, the cell used for communication with the mobile station device 1 among the cells of the base station device 2 is a serving cell. The other cells are referred to as neighboring cells (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.

[Component carrier configuration setting example]
FIG. 4 shows the downlink component carrier and the uplink component carrier that the base station device 2 sets for the mobile station device 1 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 correspondence. In FIG. 4, the correspondence relationship between two downlink component carriers (downlink component carrier DL_CC1, downlink component carrier DL_CC2) and two uplink component carriers (uplink component carrier UL_CC1, uplink component carrier UL_CC2). As shown, the present invention is not limited to the case of two component carriers. In FIG. 4, the downlink component carrier DL_CC1 and the uplink component carrier UL_CC1, and the downlink component carrier DL_CC2 and the uplink component carrier UL_CC2 are respectively cell-specific connected (Cell Specific Linkage).

The cell-specific connection is, for example, a correspondence relationship (linkage relationship) between uplink and downlink frequencies accessible to the base station device 2 when the mobile station device 1 is not carrier-aggregated. The part of the broadcast information (SIB2: System Information Block Type2) indicates the corresponding relationship. 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 is instructed implicitly by using information on the prescribed 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 uplink and downlink frequencies can be shown for each cell.

On the other hand, the base station apparatus 2 individually sets the correspondence relationship 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 an RRC message (layer 3 message). The base station apparatus 2 can also assign a plurality of settings (configurations) necessary for transmission of the physical random access channel for each uplink component carrier or each uplink frequency.

A cell composed of an uplink component carrier in which radio resource request uplink control channel setting is performed and a downlink component carrier that is cell-specifically connected to the uplink component carrier is a primary cell (PCell: Primary cell). Called. Moreover, the cell comprised from component carriers other than a primary cell is called a secondary cell (SCell: Secondary cell). Although the primary cell is not subject to activation / inactivation control (that is, it is always considered to be activated), the secondary cell has a state of activation / inactivation. These state changes are performed based on a timer set in the mobile station apparatus 1 for each component carrier, in addition to being explicitly designated from the base station apparatus 2. The primary cell and the secondary cell are also collectively referred to as a serving cell.

Here, the activation or deactivation of the component carrier (ie, activation or deactivation of the secondary cell) is configured to be controlled by an L2 (Layer 2) message that can be interpreted by a Layer 2 configuration task. The That is, activation or deactivation is controlled by a control command recognized by layer 2 after being decoded by the physical layer (layer 1). Note that 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.

The mobile station device 1 may stop monitoring the uplink grant and the downlink grant (downlink assignment) used for scheduling the deactivated component carrier (secondary cell). That is, monitoring of the physical downlink control channel may be stopped. Moreover, the mobile station apparatus 1 may stop the transmission of the uplink pilot channel called a sounding reference signal (SRS) regarding the uplink of the deactivated component carrier (secondary cell). Moreover, the mobile station apparatus 1 may stop transmission of a physical uplink control channel regarding the uplink of the deactivated component carrier (secondary cell). Moreover, the mobile station apparatus 1 may implement a measurement with a sampling rate lower than the activated state regarding the downlink of the deactivated component carrier (secondary cell).

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 embodiments of the present invention, if it is determined that specific descriptions of known functions and configurations related to the present invention will obscure the spirit of the present invention, detailed descriptions thereof will be given. Don't do it.

[First Embodiment]
A first embodiment of the present invention will be described below. The present embodiment relates to a power headroom reporting method at the time of carrier aggregation of the mobile station apparatus 1, and particularly shows a power headroom reporting method when the mobile station apparatus 1 manages a plurality of uplink transmission timings.

FIG. 5 is a block diagram showing a schematic configuration example of the mobile station apparatus 1 according to the first embodiment of the present invention. The mobile station apparatus 1 includes a reception unit 101, a demodulation unit 102, a decoding unit 103, a measurement processing unit 104, a control unit 105, a random access control unit 106, a coding unit 107, a modulation unit 108, a transmission unit 109, a timing management unit 110, An upper layer 111 and a PHR calculation unit 112 are included. 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) layer 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, and control information related to reception is appropriately input to the reception unit 101, the demodulation unit 102, and the decoding unit 103 as reception control information. 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 system parameters. Input to the control unit 105 as necessary. Further, 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 demodulated signal to decoding section 103. The decoding unit 103 correctly decodes downlink data and downlink control data from the signal, and inputs each decoded data to the upper layer 111. The measurement processing unit 104 measures the measurement result of the downlink reference signal reception quality (SIR, SINR, RSRP, RSRQ, RSSI, path loss, etc.) for each cell (component carrier), the physical downlink control channel, or the physical downlink shared channel. Downlink measurement information is generated based on the measurement result of the reception error rate, and the downlink measurement information is input to the upper layer 111. The downlink measurement information is used in the upper layer 111 for detection of a radio link failure (Radio link failure) accompanied by radio link re-establishment and radio link monitoring (Radio link monitoring) accompanied by suspension of uplink transmission. It is done.

Similarly, the downlink measurement information of the measurement processing unit 104 is input to the PHR calculation unit 112. In the PHR calculation unit 112, PHR control information including parameters necessary for PHR reporting is set by the upper layer 111. The PHR control information includes at least a plurality of timers related to PHR reporting (PHR reporting prohibition timer, PHR period timer), a PHR reporting format (type 1 or type 2), a difference value of change in path loss used for a trigger condition, and PHR. Includes offset values and coefficients for the calculation of.

The PHR calculation unit 112 calculates the value of the power headroom for each activated component carrier (secondary cell) based on the set PHR control information, downlink measurement information, and uplink transmission state. Further, the PHR calculation unit 112 determines, for each subframe, whether the PHR trigger condition is satisfied based on the input downlink measurement information and the states of a plurality of timers included in the PHR control information. When the PHR calculation unit 112 determines that any of the trigger conditions of the PHR is satisfied, the transmission state of the uplink physical channel in the subframe at the time of the trigger, the set report format, and the downlink measurement The PHR value calculated based on the information is input to the upper layer 111.

Prior to transmission, mobile station apparatus control information is input from the upper layer 111 to the control unit 105, and control information related to transmission is appropriately transmitted to the random access control unit 106, encoding unit 107, modulation unit 108, and transmission unit 109 as transmission control information. Is input. 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. The encoding unit 107 appropriately encodes each data according to the transmission control information and inputs the data to the modulation unit 108.

The modulation unit 108 modulates the input from the coding unit 107. The transmission unit 109 maps the input from the modulation unit 108 to the frequency domain, converts the frequency domain signal into a time domain signal, and amplifies the power 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. 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 apparatus 1 are not shown because they are not related to the present embodiment.

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

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

Also, the receiving 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 demodulation unit 202 is subsequently input to the decoding unit 203 and decoded, and the correctly decoded uplink control data and uplink data are input to the upper layer 208. The base station apparatus control information necessary for control of these blocks is information necessary for radio communication control of the base station apparatus 2 configured by reception control information and transmission control information. Gateway device) and 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 to each block of the encoding unit 205, modulation unit 206, and transmission unit 207 as transmission control information. The control unit 204 appropriately inputs base station apparatus control information related to reception to each block of the reception unit 201, the demodulation unit 202, and the decoding unit 203 as reception control information. 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 apparatuses 2 or between the host network apparatus and the base station apparatus 2. In FIG. 6, the other components of the base station apparatus 2 are not shown 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.

The timing at which the mobile station apparatus 1 that manages a plurality of transmission timings can report PHR will be described with reference to FIG. The horizontal axis of FIG. 7 shows the history of time. The mobile station device 1 is started from a state in which at least one inactivated secondary cell is set from the base station device 2. Such a state can typically be regarded as a state after a new secondary cell is added or a state after the handover is performed. Further, the secondary cell requires uplink transmission timing different from that of the primary cell.

Time T01 indicates that the mobile station apparatus 1 has received the activation command for the deactivated secondary cell. The activation command may be notified by a MAC control element as usual, or may be notified by an RRC message or a physical downlink control channel.

At this time, the mobile station apparatus 1 applies the necessary settings accompanying the activation of the secondary cell, such as the downlink measurement processing of the activated secondary cell and, in some cases, transmission of an uplink reference signal in the uplink. Processing time is required. The mobile station apparatus 1 considers that the secondary cell is actually activated at time T02 when a delay time n1 (for example, 8 subframes) used for this processing time has elapsed. The time T02 coincides with the timing at which the random access procedure for the secondary cell can be started.

The mobile station apparatus 1 starts a random access procedure in the secondary cell at any timing after time T02 and transmits a physical random access channel to the base station apparatus 2. Typically, the random access procedure is started in the latest subframe in which there is a random access resource that can be used by the mobile station apparatus 1 after time T02. Then, the mobile station apparatus 1 receives a random access response from the base station apparatus 2 at time T03. The random access procedure is performed in the secondary cell.

The timing at which the mobile station apparatus 1 starts the random access procedure in the secondary cell between the time T02 and the time T03 is, for example, (1) the same as the timing when the secondary cell is activated, (2) activation of the secondary cell When the start of random access is instructed later by the MAC control element, (3) when the start of random access is instructed by the physical downlink control channel PDCCH after the activation of the secondary cell, etc. are conceivable. In the present embodiment, any of the timings described above may be used.

At time T03, the mobile station apparatus 1 receives the random access response to acquire the uplink transmission timing (secondary cell uplink transmission timing) of the secondary cell cell. The mobile station device 1 needs a delay time n2 as a processing time for adjusting the uplink transmission timing of the secondary cell. The mobile station apparatus 1 determines that the power headroom report of the secondary cell is possible (PHR transmission is possible) after time T04 when the delay time n2 (for example, 4 subframes) has elapsed.

And the mobile station apparatus 1 starts the procedure similar to the case where the trigger conditions of PHR are satisfy | filled, and includes PHR of a primary cell, a transmission timing adjustment state, and the activated secondary cell in a MAC control element. Transmit to the base station apparatus 2.

That is, the mobile station apparatus 1 of the present embodiment is when (1) the PHR report prohibition timer (Prohibit PHR timer) is stopped as a PHR trigger condition instead of the conventional EUTRA PHR trigger condition. (2) PHR period timer (Periodic PHR timer) when the path loss value of the primary cell or the transmission timing adjustment state and the activated secondary cell has deteriorated by more than a predetermined value than when the previous PHR was reported Is used, (3) when the PHR setting is changed, and (4) when the secondary cell is activated to enter the transmission timing adjustment state. The mobile station apparatus 1 transmits the PHR between the primary cell and the activated secondary cell in the transmission timing adjustment state to the base station apparatus 2 when any of the above-described PHR trigger conditions is satisfied.

FIG. 8 is a sequence chart showing the exchange of signaling related to the power headroom report accompanying the activation of the secondary cell between the mobile station apparatus 1 and the base station apparatus 2 according to the present embodiment. The mobile station device 1 is started from a state in which at least one inactivated secondary cell is set from the base station device 2. Furthermore, the uplink transmission timing different from the primary cell is set for the secondary cell.

Here, in step S101, an activation command for the secondary cell in the transmission timing non-adjusted state is notified from the base station apparatus 2. The activation command may be notified by a MAC control element as usual, or may be notified by an RRC message or a physical downlink control channel.

The mobile station apparatus 1 determines a random access trigger as to whether or not to start the random access procedure for the activated secondary cell (step S102). The timing when the mobile station device 1 starts the random access procedure in the secondary cell is, for example, (1) the same as the timing when the secondary cell is activated, or (2) the random access procedure is performed by the MAC control element after the activation of the secondary cell. When the start is instructed, (3) When the start of the random access procedure is instructed on the physical downlink control channel PDCCH after the activation of the secondary cell, (4) The layer 3 message (RRC message) after the activation of the secondary cell Or when the start of a random access procedure is instructed. In the present embodiment, any of the timings described above may be used.

In step S103, the mobile station apparatus 1 starts a random access procedure for the secondary cell in the transmission timing non-adjusted state, and transmits a physical random access channel to the base station apparatus 2. When receiving the physical random access channel, the base station apparatus 2 transmits a random access response to the mobile station apparatus 1 in step S104. The details of step S103 and step S104 may be the same as in FIG. 1 or FIG.

Then, the mobile station apparatus 1 performs secondary cell uplink transmission timing acquisition (step S105), and acquires uplink transmission timing adjustment information from the random access response in step S104. The uplink transmission timing is adjusted after a predetermined time (for example, after 4 subframes) after acquiring the transmission timing adjustment information. When the uplink state of the newly activated secondary cell becomes the transmission timing adjustment state, the mobile station device 1 determines that the PHR trigger condition is satisfied, and determines the PHR notified from the physical layer. A power headroom report is made by setting the MAC control information (step S106).

FIG. 9 is a flowchart regarding power headroom reporting accompanying activation of the secondary cell of the mobile station apparatus 1 according to the present embodiment. This flowchart is started when at least one secondary cell in the transmission timing non-adjusted state is set for the mobile station apparatus 1 and an activation command for the secondary cell is received.

First, the mobile station apparatus 1 monitors whether or not a random access procedure is triggered for the secondary cell (step S201). The timing when the mobile station device 1 starts the random access procedure in the secondary cell is, for example, (1) the same as the timing when the secondary cell is activated, (2) the random access is started by the MAC control element after the secondary cell is activated (3) When the start of random access is instructed on the physical downlink control channel PDCCH after activation of the secondary cell, (4) Random in layer 3 message (RRC message) after activation of the secondary cell When the start of access is instructed, etc. In the present embodiment, any of the timings described above may be used.

The mobile station apparatus 1 proceeds to step S202 when the secondary cell random access procedure is started, otherwise returns to step S201 and continuously monitors the trigger.

The mobile station apparatus 1 starts a random access procedure in step S202. Then, the mobile station apparatus 1 monitors the timing at which the power headroom can be reported in parallel with the execution of the random access procedure, and determines whether or not the power headroom can be reported every subframe (step) S203). As described above, the mobile station apparatus 1 determines that the power headroom can be reported when the uplink state of the secondary cell activated by the random access procedure becomes the transmission timing adjustment state. In other words, the mobile station apparatus 1 determines that the power headroom can be reported after a predetermined time has elapsed after receiving the transmission timing adjustment information of the activated secondary cell.

Then, the mobile station apparatus 1 reports the power headroom by including the PHR of the primary cell notified from the physical layer and the PHR of the activated secondary cell in the transmission timing adjustment state in the MAC control information (step S204). .

The random access procedure applied to FIGS. 7 to 9 may be either a contention based random access (contention based random access) procedure or a non-contention based random access (non-contention based random access) procedure. . That is, regardless of which random access procedure is started, transmission timing adjustment information of the newly activated secondary cell is notified from the base station apparatus 2 to the mobile station apparatus 1 by a random access response, and the mobile station apparatus 1 is the same in that the PHR is transmitted after adjusting the uplink transmission timing of the activated secondary cell based on the transmission timing adjustment information.

In addition, when the activated secondary cell has the same uplink transmission timing as that of the primary cell, the mobile station device 1 has the uplink transmission timing adjusted for the activated secondary cell (transmission timing adjustment state). If the uplink is not set in the activated secondary cell, the conventional PHR report trigger condition is applied.

Furthermore, the PHR reporting format may be either type 1 or type 2, and any of them does not affect the spirit of the present invention.

Thus, according to the first embodiment, when a cell (secondary cell) having an uplink frequency (uplink component carrier) whose uplink transmission timing is not adjusted is set in the mobile station apparatus 1. The base station apparatus 2 activates the secondary cell to cause the mobile station apparatus 1 to report the power headroom of the related cell after adjusting the uplink transmission timing of the secondary cell. In addition, when a secondary cell whose uplink transmission timing is not adjusted is activated, the mobile station apparatus 1 starts a random access procedure, adjusts the uplink transmission timing of the secondary cell, and then sets the power headroom as a base. Transmit to the station apparatus 2.

As described above, by configuring as in the first embodiment, the mobile station apparatus 1 reports the PHR of the component carrier (that is, the deactivated secondary cell) that cannot be scheduled to the base station apparatus 2. It is possible to solve the problem of conventional EUTRA.

The mobile station apparatus 1 according to the present embodiment reports the power headroom after starting the random access procedure and adjusting the transmission timing. The mobile station apparatus 1 can be reused without extending the L2 message used for power headroom reporting. As described above, since the mobile station apparatus 1 reports the power headroom of the cell (component carrier) activated after the transmission timing adjustment state is established by the random access procedure, it is possible to reduce useless signaling. It becomes.

Further, since the base station apparatus 2 of the present embodiment knows that the power headroom reported by the mobile station apparatus 1 is a schedulable component carrier, the secondary cell modulation scheme and the Resource allocation can be performed efficiently. Thus, the base station apparatus 2 can perform appropriate scheduling based on the reported power headroom.

[Second Embodiment]
A second embodiment of the present invention will be described below. In the present embodiment, a power headroom reporting method for reporting power headroom after a random access procedure is successful will be described. The configurations of mobile station apparatus 1 and base station apparatus 2 used in the present embodiment may be the same as those shown in FIGS.

The timing at which the mobile station apparatus 1 that manages a plurality of transmission timings can report PHR will be described with reference to FIG. The horizontal axis of FIG. 10 shows the history of time. The mobile station device 1 is started from a state in which at least one inactivated secondary cell is set from the base station device 2. Such a state can typically be regarded as a state after a new secondary cell is added or a state after the handover is performed. Further, the secondary cell requires uplink transmission timing different from that of the primary cell.

The series of processing from time T01 to time T04 in FIG. 10 is the same as that in FIG.

The mobile station apparatus 1 performs the random access procedure being executed if necessary after time T04 when a delay time n2 (for example, 4 subframes) has elapsed as a processing time for adjusting the uplink transmission timing of the secondary cell. Continue. And the mobile station apparatus 1 judges that the power headroom report of the said secondary cell is possible (PHR transmission is possible) after the time T05 when the random access procedure was successful.

That is, the mobile station apparatus 1 of the present embodiment is when (1) the PHR report prohibition timer (Prohibit PHR timer) is stopped as a PHR trigger condition instead of the conventional EUTRA PHR trigger condition. (2) PHR period timer (Periodic PHR timer) when the path loss value of the primary cell or the transmission timing adjustment state and the activated secondary cell has deteriorated by more than a predetermined value than when the previous PHR was reported Is used, (3) when the PHR setting is changed, and (4) when the secondary cell random access procedure is successful. The mobile station apparatus 1 transmits the PHR between the primary cell and the activated secondary cell in the transmission timing adjustment state to the base station apparatus 2 when any of the above-described PHR trigger conditions is satisfied.

FIG. 11 and FIG. 12 are sequence charts showing the exchange of signaling related to the power headroom report accompanying the activation of the secondary cell between the mobile station apparatus 1 and the base station apparatus 2 according to the present embodiment. FIG. 11 shows an example when the contention based random access procedure is performed, and FIG. 12 shows an example when the non-contention based random access procedure is performed.

In FIG. 11, the mobile station device 1 starts from a state in which at least one inactivated secondary cell is set from the base station device 2. Furthermore, the uplink transmission timing different from the primary cell is set for the secondary cell.

Here, in step S301, an activation command for the secondary cell in the transmission timing non-adjusted state is notified from the base station apparatus 2. The activation command may be notified by a MAC control element as usual, or may be notified by an RRC message or a physical downlink control channel.

The mobile station apparatus 1 determines a random access trigger as to whether or not to start a random access procedure for the activated secondary cell (step S302). The timing at which the mobile station apparatus 1 starts the random access procedure in the secondary cell may be the same as that described in step S102 in FIG. 8, and therefore detailed description thereof will not be repeated. However, the base station apparatus 2 does not notify the mobile station apparatus 1 of the individual preamble, and the mobile station apparatus 1 starts the Contention based Random Access procedure as a random access procedure.

In step S303, the mobile station apparatus 1 starts the contention based random access procedure for the secondary cell in the transmission timing non-adjusted state, and transmits the physical random access channel to the base station apparatus 2. When receiving the physical random access channel, the base station apparatus 2 transmits a random access response to the mobile station apparatus 1 in step S304. The details of step S303 and step S304 may be the same as in FIG.

Then, the mobile station apparatus 1 performs secondary cell uplink transmission timing acquisition (step S305), and acquires uplink transmission timing adjustment information from the random access response in step S304. The uplink transmission timing is adjusted after a predetermined time (for example, after 4 subframes) after acquiring the transmission timing adjustment information. The mobile station apparatus 1 regards the uplink state of the newly activated secondary cell as a transmission timing adjustment state, and transmits an upper layer message to the base station apparatus 2 (step S306). Then, the base station device 2 transmits a collision confirmation message (contention resolution) to the mobile station device 1 (step S307). The details of step S306 and step S307 may be the same as in FIG.

The mobile station apparatus 1 analyzes the contention resolution received in step S307 and confirms whether it is a response to the upper layer message transmitted in step S306. When confirming that the response is to the upper layer message, the mobile station apparatus 1 determines that the contention based random access procedure has been successful (step S308). When the contention based random access procedure is successful, the mobile station apparatus 1 determines that the PHR trigger condition is satisfied, sets the PHR notified from the physical layer in the MAC control information, and performs power headroom reporting (steps). S309).

On the other hand, in FIG. 12, the mobile station apparatus 1 starts from a state in which at least one inactivated secondary cell is set from the base station apparatus 2. Further, the secondary cell requires uplink transmission timing different from that of the primary cell.

Here, in step S401, an activation command for the secondary cell in the transmission timing non-adjusted state is notified from the base station apparatus 2. The activation command may be notified by a MAC control element as usual, or may be notified by an RRC message or a physical downlink control channel.

The mobile station apparatus 1 determines a random access trigger as to whether or not to start a random access procedure for the activated secondary cell (step S402). The timing at which the mobile station apparatus 1 starts the random access procedure in the secondary cell may be the same as that described in step S102 in FIG. 8, and therefore detailed description thereof will not be repeated. However, the base station apparatus 2 notifies the mobile station apparatus 1 of an individual preamble, and the mobile station apparatus 1 starts a non-contention based random access procedure as a random access procedure. The method in which the base station apparatus 2 notifies the mobile station apparatus 1 of the dedicated preamble is one or more of a method in which the dedicated preamble is included in the PDCCH, a method in which the MAC control element notifies, and a method in which the RRC message notifies. Can be used.

In step S403, the mobile station apparatus 1 starts a non-contention based random access procedure for the secondary cell in the transmission timing non-adjusted state, and transmits a physical random access channel to the base station apparatus 2. When receiving the physical random access channel, the base station apparatus 2 transmits a random access response to the mobile station apparatus 1 in step S404. The details of step S403 and step S404 may be the same as in FIG.

Then, the mobile station apparatus 1 performs secondary cell uplink transmission timing acquisition (step S405), and acquires uplink transmission timing adjustment information from the random access response of step S404. The uplink transmission timing is adjusted after a predetermined time (for example, after 4 subframes) after acquiring the transmission timing adjustment information. The mobile station apparatus 1 regards the uplink state of the newly activated secondary cell as the transmission timing adjustment state.

The mobile station apparatus 1 determines that the Non-contention based Random Access procedure has been successful by receiving the random access response in Step S404 in parallel with the processing in Step S405 (Step S406). When the non-contention based Random Access procedure is successful, the mobile station apparatus 1 determines that the PHR trigger condition is satisfied, sets the PHR notified from the physical layer in the MAC control information, and performs power headroom reporting (Step S407).

The flowchart regarding the power headroom report accompanying the activation of the secondary cell of the mobile station apparatus 1 according to the present embodiment can be described using the same flowchart as FIG. However, in step S203 of FIG. 9, the mobile station apparatus 1 determines that the power headroom can be reported, and when the random access procedure executed in the activated secondary cell succeeds, Determine that the room is reportable. In other words, when the mobile station apparatus 1 receives a contention resolution addressed to itself if it is a Contention based Random Access procedure, it receives a random access response if it is a Non-contention based Random Access procedure. Sometimes, it is determined that the power headroom of the secondary cell that has performed the random access can be reported.

In addition, the mobile station apparatus 1 is the case where the activated secondary cell has the same uplink transmission timing as the primary cell, or the activated secondary cell has the uplink transmission timing adjusted (transmission timing adjustment state). In some cases, or when an uplink is not set in the activated secondary cell, a conventional trigger condition for PHR reporting is applied.

As described above, according to the second embodiment, when a cell (secondary cell) having an uplink frequency (uplink component carrier) whose uplink transmission timing is not adjusted is set in the mobile station apparatus 1. The base station apparatus 2 activates the secondary cell to cause the mobile station apparatus 1 to report the power headroom of the related cell after the random access procedure in the secondary cell is successful. Moreover, when the secondary cell whose uplink transmission timing is not adjusted is activated, the mobile station apparatus 1 starts a random access procedure, and after the random access procedure is successful, the mobile station apparatus 1 transfers the power headroom to the base station apparatus 2. Send.

As described above, by configuring as in the second embodiment, the mobile station apparatus 1 reports the PHR of the component carrier (that is, the deactivated secondary cell) that cannot be scheduled to the base station apparatus 2. It is possible to solve the problem of conventional EUTRA.

In particular, in the second embodiment, since the power headroom is reported after confirming that the random access procedure is successful, if the random access procedure fails after adjusting the transmission timing (particularly, in the Contention based Random Access procedure). It is possible to report the power headroom efficiently in consideration of (which may occur). In other words, since the mobile station apparatus 1 reports the power headroom after the secondary cell can be scheduled by the base station apparatus 2, it is possible to reduce useless signaling.

The mobile station apparatus 1 of the present embodiment reports the power headroom after the random access procedure is successful. The mobile station apparatus 1 can be reused without extending the L2 message used for power headroom reporting. Thus, since the mobile station apparatus 1 reports the power headroom of the cell (component carrier) activated after the random access procedure is successful, it is possible to reduce useless signaling.

Note that the embodiment described above is merely an example, and can be realized by using various modifications and replacement examples. For example, this uplink transmission scheme can be applied to both communication systems of the FDD (frequency division duplex) scheme and the 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. However, 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 Is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into a computer system and executed to control the mobile station apparatus 1 and the base station apparatus 2. May be performed. 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 device 1 and the base station device 2 used in the above embodiments may be configured in a circuit including an LSI that is typically an IC (integrated circuit). . 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.

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. In other words, the description in the present specification is for illustrative purposes and does not limit the present invention.

1 mobile station device, 2 base station device, 11, 12, 13 transmission device, 21, 22, 23 reception device, 101, 201 reception unit, 102, 202 demodulation 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, 112 PHR calculation unit, 209 network signal transmission / reception unit DL_CC downlink component carrier, PDCCH physical downlink control channel, PUCCH physical uplink control channel, PUSCH physical uplink shared channel, UL_CC uplink component carrier.

Claims

A communication system for reporting to a base station device a power headroom indicating a surplus of transmission power of a plurality of serving cells to which a mobile station device is connected,
The plurality of serving cells have a first serving cell having the same uplink transmission timing as the primary cell, and an uplink transmission timing different from the first serving cell, and is activated or deactivated A second serving cell to be
The base station device activates the second serving cell set in the mobile station device,
In the mobile station apparatus, the uplink transmission timing of the second serving cell activated by the base station apparatus is based on transmission timing adjustment information related to the second serving cell received from the base station apparatus. The communication system which judges that the trigger condition of the report of a power headroom was satisfy | filled when it came to the adjustment state.
The communication system according to claim 1, wherein the base station apparatus notifies the transmission timing adjustment information using a Contention based Random Access procedure.
The communication system according to claim 1, wherein the base station apparatus notifies the transmission timing adjustment information using a Non-contention based Random Access procedure.
When determining that the power headroom report trigger condition is satisfied, the mobile station apparatus, based on the activation state of the plurality of serving cells and the adjustment state of uplink transmission timing, The communication system according to claim 1, wherein a serving cell reporting power headroom is determined.
The mobile station apparatus reports the power headroom of the second serving cell in which the mobile station apparatus is activated and the uplink transmission timing is in an adjusted state to the base station apparatus. Communication system.
A communication system for reporting to a base station device a power headroom indicating a surplus of transmission power of a plurality of serving cells to which a mobile station device is connected,
The plurality of serving cells have a first serving cell having the same uplink transmission timing as the primary cell, and an uplink transmission timing different from the first serving cell, and is activated or deactivated A second serving cell to be
The base station device activates the second serving cell set in the mobile station device,
The mobile station apparatus performs a random access procedure in the second serving cell activated by the base station apparatus, and based on success or failure of the random access procedure, a trigger condition for reporting power headroom is set. A communication system that determines whether or not the condition is satisfied.
The random access procedure is a contention based random access procedure,
The communication system according to claim 6, wherein the mobile station apparatus determines whether a trigger condition for the power headroom is satisfied based on whether the contention resolution is correctly received.
The random access procedure is a non-contention based random access procedure,
The communication system according to claim 6, wherein the mobile station apparatus determines whether a trigger condition for the power headroom is satisfied based on whether or not a random access response is correctly received.
When determining that the power headroom report trigger condition is satisfied, the mobile station apparatus, based on the activation state of the plurality of serving cells and the adjustment state of uplink transmission timing, The communication system according to claim 6, wherein a serving cell reporting power headroom is determined.
The mobile station apparatus reports the power headroom of the second serving cell in which the mobile station apparatus is activated and the uplink transmission timing is in an adjusted state to the base station apparatus. Communication system.
A mobile station apparatus in a communication system that reports power headroom indicating the remaining power of transmission power of a plurality of serving cells to which the mobile station apparatus is connected to the base station apparatus,
The plurality of serving cells have a first serving cell having the same uplink transmission timing as the primary cell, and an uplink transmission timing different from the first serving cell, and is activated or deactivated A second serving cell to be
When the uplink transmission timing of the second serving cell activated by the base station apparatus is in an adjustment state based on the transmission timing adjustment information related to the second serving cell received from the base station apparatus In addition, the mobile station apparatus determines that the power headroom reporting trigger condition is satisfied.
The mobile station apparatus according to claim 11, wherein the transmission timing adjustment information is received from the base station apparatus using a Contention based Random Access procedure.
The mobile station apparatus according to claim 11, wherein the transmission timing adjustment information is received from the base station apparatus using a Non-contention based Random Access procedure.
When it is determined that the trigger condition for reporting the power headroom is satisfied, the power headroom is reported based on the activation state of the plurality of serving cells and the adjustment state of uplink transmission timing The mobile station apparatus according to claim 11, wherein a serving cell is determined.
The mobile station apparatus according to claim 14, wherein the mobile station apparatus reports the power headroom of the second serving cell in which the uplink transmission timing is in an adjusted state to the base station apparatus.
A mobile station apparatus in a communication system that reports power headroom indicating the remaining power of transmission power of a plurality of serving cells to which the mobile station apparatus is connected to the base station apparatus,
The plurality of serving cells have a first serving cell having the same uplink transmission timing as the primary cell, and an uplink transmission timing different from the first serving cell, and is activated or deactivated A second serving cell to be
A random access procedure is executed in the second serving cell activated by the base station apparatus, and whether a trigger condition for power headroom reporting is satisfied based on success or failure of the random access procedure is determined. A mobile station device to judge.
When the random access procedure is a Contention based Random Access procedure, it is determined whether the trigger condition of the power headroom is satisfied based on whether the contention resolution is correctly received. The mobile station apparatus as described in.
17. When the random access procedure is a non-contention based random access procedure, it is determined whether or not a trigger condition of the power headroom is satisfied based on whether or not a random access response is correctly received. The mobile station apparatus as described in.
When it is determined that the trigger condition for reporting the power headroom is satisfied, the power headroom is reported based on the activation state of the plurality of serving cells and the adjustment state of uplink transmission timing The mobile station apparatus according to claim 16, wherein a serving cell is determined.
The mobile station apparatus according to claim 19, wherein the mobile station apparatus reports to the base station apparatus the power headroom of the second serving cell that is activated and whose uplink transmission timing is in an adjusted state.
A base station apparatus in a communication system that reports power headroom indicating the remaining power of transmission power of a plurality of serving cells to which a mobile station apparatus is connected to the base station apparatus,
The plurality of serving cells have a first serving cell having the same uplink transmission timing as the primary cell, and an uplink transmission timing different from the first serving cell, and is activated or deactivated A second serving cell to be
The second serving cell set in the mobile station device is activated, transmission timing adjustment information related to the activated second serving cell is transmitted to the mobile station device, and the second serving cell of the second serving cell is transmitted. A base station apparatus that causes the mobile station apparatus to determine that a trigger condition for power headroom reporting is satisfied by setting an uplink transmission timing to an adjusted state.
A base station apparatus in a communication system that reports power headroom indicating the remaining power of transmission power of a plurality of serving cells to which a mobile station apparatus is connected to the base station apparatus,
The plurality of serving cells have a first serving cell having the same uplink transmission timing as the primary cell, and an uplink transmission timing different from the first serving cell, and is activated or deactivated A second serving cell to be
By activating the second serving cell set in the mobile station device and causing the mobile station device to execute a random access procedure of the activated second serving cell, the mobile station device causes the mobile station device to execute the random access procedure. A base station apparatus that determines whether a trigger condition for power headroom reporting is satisfied based on success or failure of a random access procedure.
A power headroom reporting method in a communication system for reporting to a base station device a power headroom indicating the remaining power of transmission power of a plurality of serving cells to which a mobile station device is connected,
The plurality of serving cells have a first serving cell having the same uplink transmission timing as the primary cell, and an uplink transmission timing different from the first serving cell, and is activated or deactivated A second serving cell to be
The base station device activates the second serving cell set in the mobile station device,
In the mobile station apparatus, the uplink transmission timing of the second serving cell activated by the base station apparatus is based on transmission timing adjustment information related to the second serving cell received from the base station apparatus. A power headroom reporting method for determining that a trigger condition for power headroom reporting is satisfied when an adjustment state is reached.
A power headroom reporting method in a communication system for reporting to a base station device a power headroom indicating the remaining power of transmission power of a plurality of serving cells to which a mobile station device is connected,
The plurality of serving cells have a first serving cell having the same uplink transmission timing as the primary cell, and an uplink transmission timing different from the first serving cell, and is activated or deactivated A second serving cell to be
The base station device activates the second serving cell set in the mobile station device,
The mobile station apparatus performs a random access procedure in the second serving cell activated by the base station apparatus, and based on success or failure of the random access procedure, a trigger condition for reporting power headroom is set. A power headroom reporting method to determine if it has been met.
An integrated circuit mounted on a mobile station device in a communication system that reports to a base station device a power headroom indicating the remaining power of transmission power of a plurality of serving cells to which the mobile station device is connected,
The plurality of serving cells have a first serving cell having the same uplink transmission timing as the primary cell, and an uplink transmission timing different from the first serving cell, and is activated or deactivated A second serving cell to be
When the uplink transmission timing of the second serving cell activated by the base station apparatus is in an adjustment state based on the transmission timing adjustment information related to the second serving cell received from the base station apparatus And the integrated circuit determines that the power headroom reporting trigger condition has been met.
An integrated circuit mounted on a mobile station device in a communication system that reports to a base station device a power headroom indicating the remaining power of transmission power of a plurality of serving cells to which the mobile station device is connected,
The plurality of serving cells have a first serving cell having the same uplink transmission timing as the primary cell, and an uplink transmission timing different from the first serving cell, and is activated or deactivated A second serving cell to be
A random access procedure is executed in the second serving cell activated by the base station apparatus, and whether a trigger condition for power headroom reporting is satisfied based on success or failure of the random access procedure is determined. Integrated circuit to judge.