JP2012005035A - Mobile station apparatus, base station apparatus, wireless communication system, wireless communication method, and integrated circuit - Google Patents

Abstract

A mobile station device, a base station device, a wireless communication system, and a wireless communication device capable of performing efficient communication between a base station device and a mobile station device based on an A-SRS transmitted from the mobile station device A communication method and an integrated circuit are provided.
A base station apparatus notifies a mobile station apparatus of an uplink grant including frequency resource allocation information of a physical uplink shared channel and a sounding reference signal transmission instruction, and the mobile station apparatus is notified of the uplink. When the grant includes a sounding reference signal A-SRS transmission instruction, the sounding reference signal A-SRS resource including the PUSCH frequency resource is set according to the information on the physical uplink shared channel resource allocation, and the sounding reference Signal A-SRS is transmitted.
[Selection] Figure 3

Description

  The present invention relates to a radio communication system including a mobile station apparatus and a base station apparatus, and more particularly to a transmission control method for a reference signal for channel measurement of a mobile station apparatus.

  Traditionally, cellular mobile radio access schemes and radio network evolution (hereinafter also referred to as “Long Term Evolution (LTE)” or “Evolved Universal Terrestrial Radio Access (EUTRA)”) and wider bandwidth than LTE A wireless access method and wireless network ("Long Term Evolution-Advanced (LTE-A)" or "Advanced Evolved Universal Terrestrial Radio Access (A- EUTRA) ”is also being considered in the 3rd Generation Partnership Project (3GPP).

  As communication systems in LTE, OFDMA (Orthogonal Frequency Division Multiple Access) system that performs user multiplexing using mutually orthogonal subcarriers and SC-FDMA (Single Carrier-Frequency Division Multiple Access) system are being studied. . That is, an OFDMA scheme that is a multicarrier communication scheme is proposed for the downlink, and an SC-FDMA scheme that is a single carrier communication scheme is proposed for the uplink.

  On the other hand, as a communication method in LTE-A, the OFDMA method is used in the downlink, and in the uplink, in addition to the SC-FDMA method, Clustered-SC-FDMA (Clustered-Single Carrier-Frequency Division Multiple Access, DFT-s). -OFDM with Spectrum Division Control, also called DFT-precoded OFDM) is being studied. Here, in LTE and LTE-A, the SC-FDMA system and the Clustered-SC-FDMA system proposed as uplink communication systems are based on the characteristics of the single carrier communication system (depending on the single carrier characteristics), and data (information ) Is transmitted at a low PAPR (Peak to Average Power Ratio: peak power to average power ratio, transmission power).

  In LTE-A, a frequency band used in a general wireless communication system is continuous, whereas a plurality of continuous and / or discontinuous frequency bands (hereinafter referred to as “component carrier (CC)”). Alternatively, it has been proposed to operate as one wide frequency band (also referred to as carrier aggregation) by using a combination of “carrier component (CC: Carrier Component)”. In addition, the base station device and mobile station device (UE: User Equipment) are used for downlink communication and the frequency band used for downlink communication in order to communicate more flexibly using a wide frequency band. It has also been proposed to use different frequency bandwidths (Asymmetric carrier aggregation) (Non-patent Document 1).

  FIG. 7 is a diagram for explaining a radio communication system in which frequency bands are aggregated in the prior art. It is symmetric that the frequency band used for downlink (DL: Down Link) communication and the frequency band used for uplink (UL: Up Link) communication as shown in FIG. It is also called frequency band aggregation (Symmetric carrier aggregation). As shown in FIG. 7, the base station apparatus and the mobile station apparatus can use a wide band composed of a plurality of component carriers by using a plurality of component carriers that are continuous and / or discontinuous frequency bands. Communication can be performed in the frequency band.

  In FIG. 7, as an example, the frequency band (DL system band (width) may be used) for downlink communication having a bandwidth of 100 MHz is five downlink component carriers (bandwidth of 20 MHz) ( DCC1: Downlink Component Carrier1, DCC2, DCC3, DCC4, DCC5). In addition, as an example, five uplink component carriers (UCC1: UCC1: a frequency band used for uplink communication having a bandwidth of 100 MHz (or a UL system band (width)) may be used. Uplink Component Carrier1, UCC2, UCC3, UCC4, UCC5).

  In FIG. 7, downlink channels such as a physical downlink control channel (PDCCH) and a physical downlink shared channel (PDSCH) are arranged in each downlink component carrier.

  The base station apparatus allocates (schedules) downlink control information (DCI: Downlink Control Information) for transmitting a downlink transport block transmitted using PDSCH to the mobile station apparatus using PDCCH. . The base station apparatus transmits the downlink transport block to the mobile station apparatus using PDSCH. Here, in FIG. 7, the base station apparatus can transmit up to five downlink transport blocks (or PDSCH) to the mobile station apparatus in the same subframe.

  Further, uplink channels such as a physical uplink control channel (PUCCH) and a physical uplink shared channel (PUSCH) are arranged in each uplink component carrier.

  The mobile station apparatus uses PUCCH and / or PUSCH to indicate channel state information (CSI: Channel Statement information) indicating a downlink channel state and ACK / NACK (acknowledgment: Positive) in HARQ for the downlink transport block. Information indicating Acknowledgment / Negative Acknowledgment and uplink control information (UCI) such as scheduling request (SR) are transmitted to the base station apparatus. Here, in FIG. 7, the mobile station apparatus can transmit up to five uplink transport blocks (or PUSCH) to the base station apparatus in the same subframe.

  Similarly, FIG. 8 is a diagram for explaining a wireless communication system in which asymmetric frequency bands are aggregated in the prior art. As shown in FIG. 8, the base station apparatus and the mobile station apparatus have different frequency bands used for downlink communication and frequency bands used for uplink communication, and configure these frequency bands. Therefore, it is possible to perform communication in a wide frequency band by using component carriers that are continuous and / or discontinuous frequency bands in combination.

  In FIG. 8, as an example, five downlink component carriers (DCC1, DCC2, DCC3, DCC4, DCC5) having a frequency band of 20 MHz are used for downlink communication having a bandwidth of 100 MHz. It is constituted by. In addition, as an example, it is shown that the frequency band used for uplink communication having a bandwidth of 40 MHz is configured by two uplink component carriers (UCC1, UCC2) having a bandwidth of 20 MHz. ing.

  In FIG. 8, downlink / uplink channels are allocated to downlink / uplink component carriers, respectively. The base station apparatus allocates (schedules) the PDSCH to the mobile station apparatus using the PDCCH, and transmits the downlink transport block to the mobile station apparatus using the PDSCH. Here, in FIG. 8, the base station apparatus can transmit up to five downlink transport blocks (or PDSCH) to the mobile station apparatus in the same subframe.

  Also, the mobile station apparatus uses PUCCH and / or PUSCH to transmit channel state information, information indicating ACK / NACK in HARQ for the downlink transport block, and uplink control information such as a scheduling request to the base station apparatus. Send to. Here, in FIG. 8, the mobile station apparatus can transmit up to two uplink transport blocks (or PUSCH) to the base station apparatus in the same subframe.

  In LTE-A, a sounding reference signal (A-SRS: Aperiodic Sounding Reference Signal) that is transmitted only when a transmission request is notified from the base station apparatus via the PDCCH has been proposed. By including the A-SRS transmission instruction information (A-SRS activation / deactivation) in the downlink control information (DCI) format (also referred to as DCI format), the mobile station device can be -It is possible to determine whether or not transmission of SRS is requested, and transmission control of A-SRS can be performed dynamically. Dynamic control means control for each subframe. In addition, the base station apparatus uses a downlink control information format for the downlink (DCI format, downlink grant: Downlink grant, downlink assignment: Downlink assignment) for the mobile station apparatus to -Instructing transmission of SRS, and transmitting A-SRS using downlink control information format (DCI format, uplink grant: UL grant, uplink assignment: also called uplink assignment) for uplink It has been proposed to direct. Furthermore, it has been proposed that an A-SRS transmission instruction is indicated by one bit (multi-bit) of an uplink grant or downlink assignment or a predetermined code point (Non-patent Document 2).

“Carrier aggregation in LTE-Advanced”, R1-082464, 3GPP TSG RAN WG1 Meeting # 53bis, Jun 30-Jul 4, 2008. “LTE-A Dynamic Aperiodic SRS-Duration, Timing, and Carrier Aggregation”, R1-103187, 3GPP TSG-RAN1 Meeting # 61, May 10-14, 2010.

  However, in the prior art, a mobile station apparatus instructed to transmit A-SRS by the base station apparatus transmits A-SRS to the base station apparatus without dynamically switching parameters used for A-SRS transmission. It was. That is, in order to change the A-SRS setting information, the base station apparatus adds the A-SRS setting information to the PDCCH or moves the radio resource control signal (RRC signaling) including the A-SRS setting information. I had to notify the station equipment. That is, the mobile station apparatus cannot dynamically switch parameters such as frequency resources (for example, for each subframe) and transmit the A-SRS to the base station apparatus. However, there is a problem that efficient communication cannot be performed.

  The present invention has been made in view of the above points, and can perform efficient communication between a base station apparatus and a mobile station apparatus based on A-SRS transmitted from the mobile station apparatus. An object is to provide a mobile station device, a base station device, a wireless communication system, a wireless communication method, and an integrated circuit.

  (1) In order to achieve the above object, the present invention takes the following measures. That is, the wireless communication system of the present invention is a wireless communication system in which a base station device and a mobile station device perform wireless communication, and the base station device is a wireless communication in which a base station device and a mobile station device perform wireless communication. In the communication system, the base station apparatus notifies the mobile station apparatus of an uplink grant including frequency resource allocation information of a physical uplink shared channel and a sounding reference signal transmission instruction. When the notified uplink grant includes an instruction to transmit the sounding reference signal, the sounding reference signal resource is set according to information on resource allocation of the physical uplink shared channel, and the sounding reference signal is transmitted. It is characterized by doing.

  (2) A radio communication system according to the present invention is the radio communication system according to (1), wherein the mobile station apparatus transmits a frequency of the sounding reference signal according to frequency resource allocation information of the physical uplink shared channel. It is characterized by setting resources.

  (3) A radio communication system according to the present invention is the radio communication system according to (2), in which the mobile station device is configured to use the physical uplink among frequency resources for a plurality of pre-configured sounding reference signals. The frequency resource for the sounding reference signal in which the frequency resource of the link shared channel overlaps is set as the resource of the sounding reference signal.

  (4) The radio communication system according to the present invention is the radio communication system according to (3), wherein the mobile station device has a frequency resource for the sounding reference signal that includes a plurality of physical uplink shared channel frequency resources. If the frequency resource of the sounding reference signal overlaps the frequency resource of the physical uplink shared channel most frequently, the frequency resource for the sounding reference signal is set as the resource of the sounding reference signal.

  (5) The mobile station apparatus of the present invention is a mobile station apparatus that performs radio communication with a base station apparatus, means for receiving an uplink grant notified from the base station apparatus, and sounding reference to the uplink grant Means for setting a resource of a sounding reference signal according to information related to resource allocation of a physical uplink shared channel and a means for transmitting the sounding reference signal to the base station apparatus when a signal transmission instruction is included; It is characterized by having at least.

  (6) The mobile station apparatus according to the present invention is the mobile station apparatus according to (5), in which the mobile station apparatus performs frequency of the sounding reference signal according to frequency resource allocation information of the physical uplink shared channel. It has at least means for setting resources.

  (7) A mobile station apparatus according to the present invention is the mobile station apparatus according to (6), wherein the mobile station apparatus is configured to use the physical uplink among frequency resources for a plurality of pre-configured sounding reference signals. It has at least means for setting a frequency resource for the sounding reference signal in which the frequency resource of the link shared channel overlaps to the resource of the sounding reference signal.

  (8) The mobile station apparatus according to the present invention is the mobile station apparatus according to (7), wherein the mobile station apparatus has a frequency resource for the sounding reference signal in which a frequency resource of the physical uplink shared channel is plural. If the frequency resource of the physical uplink shared channel overlaps, the frequency resource for the sounding reference signal that most overlaps the frequency resource of the physical uplink shared channel is at least included in the sounding reference signal resource.

  (9) A radio communication method according to the present invention is a radio communication method in which a base station apparatus and a mobile station apparatus perform radio communication, wherein the base station apparatus transmits frequency resource allocation information and sounding of a physical uplink shared channel. A step of notifying the mobile station apparatus of an uplink grant including an instruction to transmit a reference signal; and the mobile station apparatus includes a transmission instruction for the sounding reference signal included in the notified uplink grant. The method includes at least a step of setting a resource of a sounding reference signal according to information related to resource allocation of the physical uplink shared channel, and a step of transmitting the sounding reference signal to the base station apparatus.

  (10) The radio communication method according to the present invention is the radio communication method according to (9), wherein the mobile station apparatus uses the frequency of the sounding reference signal according to frequency resource allocation information of the physical uplink shared channel. It includes at least a step of setting a resource.

  (11) A radio communication method according to the present invention is the radio communication method according to (10), wherein the mobile station apparatus is configured to use the physical uplink among frequency resources for a plurality of pre-configured sounding reference signals. It includes at least a step of setting a frequency resource for the sounding reference signal in which a frequency resource of a link shared channel overlaps as a resource of the sounding reference signal.

  (12) The radio communication method according to the present invention is the radio communication method according to (11), wherein the mobile station device uses a frequency resource for the sounding reference signal in which a frequency resource of the physical uplink shared channel is plural. The frequency resource of the physical uplink shared channel, the frequency resource for the sounding reference signal that most overlaps the frequency resource of the physical uplink shared channel is set as the resource of the sounding reference signal.

(13) An integrated circuit according to the present invention is an integrated circuit that is mounted on a mobile station device to cause the mobile station device to perform a plurality of functions, and receives an uplink grant notified from the base station device. Function to
When the uplink grant includes a sounding reference signal transmission instruction, a function of setting a sounding reference signal resource according to information on resource allocation of a physical uplink shared channel, and the sounding reference signal as the base station apparatus. And the function of transmitting to the mobile station apparatus.

  (14) The integrated circuit according to the present invention is the integrated circuit according to (13), wherein, in the mobile station apparatus, the frequency resource of the sounding reference signal is set according to frequency resource allocation information of the physical uplink shared channel. The setting function is characterized by causing the mobile station apparatus to exhibit a function to be set.

  (15) An integrated circuit according to the present invention is the integrated circuit according to (14), wherein, in the mobile station apparatus, the physical uplink is shared among a plurality of frequency resources for sounding reference signals configured in advance. The mobile station apparatus is allowed to exhibit a function of setting a frequency resource for the sounding reference signal, in which channel frequency resources overlap, as the resource of the sounding reference signal.

  (16) An integrated circuit according to the present invention is the integrated circuit according to (15), wherein in the mobile station apparatus, a frequency resource of the physical uplink shared channel overlaps with a plurality of frequency resources for the sounding reference signal. If so, the mobile station apparatus is caused to exhibit a function of setting the frequency resource for the sounding reference signal, in which the frequency resource of the physical uplink shared channel overlaps most, as the resource of the sounding reference signal. .

  According to the present invention, a mobile station device, a base station device, a wireless communication system, a wireless communication method, and integration that can perform efficient A-SRS communication based on an uplink grant notified from the base station device. A circuit can be provided.

It is a block diagram which shows schematic structure of the base station apparatus 1 of this invention. It is a block diagram which shows schematic structure of the mobile station apparatus 3 of this invention. It is a figure which shows the frequency resource area | region of A-SRS. It is a figure which shows an example of the DCI format containing the transmission instruction | indication of A-SRS in embodiment of this invention. It is a figure which shows schematic structure of the transmission bandwidth of P-SRS. It is a figure which shows schematic structure of the resource allocation of P-SRS, and frequency hopping (FH: Frequency Hopping). It is a figure which shows the example of the frequency band aggregation in a prior art. It is a figure which shows the example of asymmetric frequency band aggregation in a prior art.

  Before entering into a specific description of an embodiment of the present invention, an outline of the communication technology used in the present invention will be briefly described.

(Physical channel)
The physical channels used in the present invention include a physical broadcast channel (PBCH), a physical downlink shared channel (PDSCH), a physical downlink control channel (PDCCH), DL-RS (Downlink Reference Signal or Cell-specific Reference Signal), Physical Uplink Shared Channel (PUSCH), Physical Uplink Control Channel (PUCCH), Physical A random access channel (PRACH: Physical Random Access Channel), an uplink reference signal (UL-RS), and the like are included. Note that the embodiments of the present invention described later can be applied even when different physical channel types are added.

  The physical broadcast channel is transmitted for the purpose of reporting control parameters (broadcast information) that are commonly used to mobile station apparatuses in the cell. Broadcast information not notified by PBCH is notified of resources by PDCCH and is transmitted using a physical downlink shared channel. As broadcast information, a cell global ID indicating an individual ID (Identity) of the cell is notified. In the PBCH, a broadcast channel (BCH) is mapped at intervals of 40 milliseconds. The timing of 40 milliseconds is subjected to blind detection in the mobile station apparatus. That is, explicit signaling is not transmitted to the mobile station apparatus for presenting the PBCH timing. In addition, a subframe including PBCH can be decoded only by the subframe (self-decodable).

  The physical downlink control channel is a downlink channel transmitted from the base station apparatus to the mobile station apparatus, and is a hybrid automatic for PDSCH resource allocation and downlink data (DL-SCH: Downlink-Shared Channel). Downlink Assignment composed of retransmission request (HARQ: Hybrid Automatic Repeat reQuest) information, physical uplink shared channel (PUSCH) resource allocation, uplink data (UL-SCH) : Channel used for notifying the mobile station apparatus of downlink control information (DCI) such as uplink transmission permission (uplink grant) which is HARQ information for Uplink-Shared Channel (uplink shared channel) It is. Moreover, PDCCH is comprised from several control channel element (CCE: Control Channel Element), and a mobile station apparatus receives PDCCH from a base station apparatus by detecting PDCCH comprised from CCE. This CCE is composed of a plurality of resource element groups (REG: Resource Element Group, also called mini-CCE) distributed in the frequency and time domains. Here, the resource element is a unit resource composed of one OFDM symbol (time component) and one subcarrier (frequency component).

  A plurality of formats are prepared for the downlink control information transmitted on the physical downlink control channel. A format of downlink control information (DCI) is called a DCI format (DCI format). For example, the DCI format of the uplink grant is a DCI format 0 that is used when the mobile station device 3 transmits the PUSCH through one transmission antenna port, and the mobile station device 3 uses the MIMO (Multiple Input Multiple Output) for the PUSCH. A DCI format 0A and the like used for transmission by multiplexing (SM: Spatial Multiplexing) are prepared.

  Also, the DCI format for downlink assignment is more than DCI format 1 and DCI format 1 used when the base station apparatus transmits PDSCH using one transmission antenna port or a plurality of transmission antenna ports using the transmission diversity scheme. DCI format 1A having a smaller number of bits, DCI format 1C having a smaller number of bits than the DCI format 1A used for radio resource allocation such as paging information, and the case where the base station apparatus transmits PDSCH by SM using MIMO. DCI format 2 and the like are prepared. In DCI format 0 and DCI format 1A, a flag (Flag for format 0 / format 1A differentiation) is used to make the sizes of the two DCI formats the same by inserting bits into the smaller number of bits and to identify the formats. Include.

  Specifically, DCI format 0, which is an uplink grant, includes PDCCH format identification (Flag for format 0 / format 1A differentiation) information, frequency hopping flag (Frequency hopping flag), resource block allocation and hopping resource allocation (Resource block assignment and hopping resource allocation) information, modulation and coding scheme and redundancy version information, NDI (New Data Indicator) information, transmission power control command (TPC command for scheduled PUSCH) information for scheduled PUSCH, Control information such as cyclic shift for DM-RS (Cyclic shift for DM-RS) information, CQI transmission instruction (CQI request) information, padding bit (0 padding) information, cyclic redundancy check (CRC) information, etc. Field, control information field, Distribution field comprised, with bit field referred to).

  The PDCCH format identification information is information indicating the type of DCI format of the downlink control information, that is, whether it is DCI format 0 or DCI format 1A. Resource block allocation and hopping resource allocation information are information indicating resource allocation in the case of hopping and resource block allocation of PUSCH. The modulation coding scheme and redundancy version information are information indicating the PUSCH modulation scheme, coding rate, and redundancy version. The NDI information is information indicating whether the PUSCH is an initial transmission or a retransmission. The PUSCH transmission power control command information is information used for PUSCH transmission power control. DM-RS cyclic shift information is information indicating a cyclic shift of DM-RS. Padding bit (0 padding) information is a bit inserted to make the sizes of DCI format 0 and DCI format 1A the same, and the value is set to “0”. The CQI transmission instruction information may instruct the mobile station apparatus to allocate the CQI using the PUSCH resource and dynamically transmit the CQI to the base station apparatus when the base station apparatus requests the CQI. it can. The CQI at this time is also referred to as an aperiodic CQI (A-CQI).

  Specifically, the DCI format 1A, which is a downlink assignment, includes PDCCH format identification (Flag for format 0 / format 1A differentiation) information, virtual resource block (VRB) centralized / distributed arrangement identification (Localized / Distributed VRB assignment flag) information, resource block assignment information, modulation and coding scheme (MCS) information, HARQ process number information, NDI (New Data Indicator) information, redundancy Control information (field, RV: Redundancy Version) information, PUCCH transmission power control (TPC) command information, padding bit (0 padding) information, cyclic redundancy check (CRC) information, etc. Control information field, information field, and bit field It consists referred to).

  The PDCCH format identification information is information indicating the type of DCI format of the downlink control information, that is, whether it is DCI format 0 or DCI format 1A. The virtual resource block centralized / distributed layout identification information is information indicating a method (centralized layout or distributed layout) for associating the virtual resource block indicated by the resource block layout information with the actual resource block. The resource block arrangement information is information indicating a virtual resource block assigned to the PDSCH. The modulation and coding scheme information is information relating to the PDSCH modulation scheme and coding rate, and the amount of downlink data transmitted on the PDSCH. The HARQ process number (HARQ process number) information is information indicating which number of HARQ process the downlink data transmitted on the PDSCH corresponding to the DCI format 1A corresponds to. The NDI information is information indicating whether the PDSCH is an initial transmission or a retransmission. The redundancy version information is information indicating which part of the bit sequence is transmitted among the bit sequences in which the downlink data is encoded. The PUCCH transmission power control command is information used for PUCCH transmission power control. Padding bit (0 padding) information is a bit inserted to make the sizes of DCI format 0 and DCI format 1A the same, and the value is set to “0”.

  Since the DCI format used for group scheduling for a plurality of mobile station apparatuses needs to be received by a plurality of mobile station apparatuses, all mobile station apparatuses try to search (detect) PDCCH (CSS: Common Search Space) Here, a PDCCH addressed to a certain mobile station device is arranged in a mobile station device specific search space (USS) and a common search region where a certain mobile station device tries to search (detect) the PDCCH.

  The base station apparatus assigns a sequence obtained by scrambling a CRC code generated based on DCI with RNTI (Radio Network Temporary Identity) to DCI, and transmits the DCI to the mobile station apparatus. The mobile station apparatus changes the interpretation of DCI depending on whether the CRC code is scrambled with any RNTI. For example, if the DCI is scrambled with the CRC code by C-RNTI (Cell-RNTI) or SPS (Semi Persistent Scheduling) C-RNTI assigned from the base station apparatus, the mobile station apparatus It is judged that it is DCI.

  The PDCCH is encoded (Separate Coding) separately for each mobile station apparatus and for each type. That is, the mobile station apparatus detects a plurality of PDCCHs, and acquires downlink resource allocation, uplink resource allocation, and other control information. Each PDCCH is assigned a CRC value scrambled by RNTI, and the mobile station apparatus descrambles a CRC scrambled by RNTI for each set of CCEs that may constitute PDCCH. (Descramble) is performed, and the CRC value is acquired. Then, CRC is performed using the acquired CRC value, and the PDCCH in which the CRC is successful is acquired as the PDCCH addressed to the own apparatus. In addition, when the scrambled CRC is scrambled with the RNTI assigned to the other device using the RNTI assigned to the own device, the correct CRC value cannot be obtained, so that it is recognized as the PDCCH addressed to the own device. do not do. This is also referred to as blind detection, and the range of CCE sets in which the mobile station apparatus may perform blind detection is referred to as a search space (Search Space). That is, the mobile station apparatus performs blind detection on CCEs in the search area, and detects PDCCH addressed to itself.

  The physical downlink shared channel is a channel used to transmit downlink data (DL-SCH: also called downlink shared channel) or paging information.

  The downlink reference signal is transmitted from the base station apparatus to the mobile station apparatus using the downlink. The mobile station apparatus determines downlink reception quality by measuring a downlink reference signal. The reception quality is notified to the base station apparatus using PUCCH or PUSCH as a channel quality indicator (CQI) which is a quality information indicator. The base station apparatus performs downlink communication scheduling for the mobile station apparatus based on the CQI notified from the mobile station apparatus. The reception quality includes signal-to-interference power ratio (SIR), signal-to-interference plus noise ratio (SINR), and signal-to-noise power ratio (SNR). Signal-to-noise ratio (CIR), carrier-to-interference ratio (CIR), block error rate (BLER), path loss (PL), and the like can be used.

  The physical uplink shared channel is a channel mainly used for transmitting uplink data (UL-SCH: Uplink Shared Channel, uplink shared channel). When the base station apparatus schedules the mobile station apparatus, channel state information (downlink channel quality indicator (CQI), precoding matrix indicator (PMI), rank indicator (RI: Rank Indicator)) and HARQ positive acknowledgment (ACK: Acknowledgement) / negative acknowledgment (NACK: Negative Acknowledgement) for downlink transmission are also transmitted using PUSCH. Here, uplink data (UL-SCH) indicates transmission of user data, for example, and UL-SCH is a transport channel. In UL-SCH, HARQ and dynamic adaptive radio link control are supported, and beamforming can be used. UL-SCH supports dynamic resource allocation and quasi-static resource allocation.

  The physical uplink control channel is a channel used for transmitting uplink control information (UCI). Here, UCI (also referred to as control data) is, for example, channel state information (CQI, PMI, RI) transmitted (feedback) from the mobile station apparatus to the base station apparatus, and the mobile station apparatus transmits uplink data. This includes a scheduling request (SR: Scheduling Request) for requesting allocation of resources for transmission (requesting transmission on UL-SCH), HARQ ACK / NACK for downlink transmission, and the like.

  The uplink reference signal is transmitted from the mobile station device to the base station device. UL-RS includes a sounding reference signal (SRS) and a demodulation reference signal (DM-RS). The SRS, which is a channel measurement reference signal, is measured by the base station apparatus to determine the reception quality of the uplink radio transmission signal of the mobile station apparatus, and uplink scheduling and uplink timing synchronization based on the reception quality are performed. Used for adjustment. Also, DM-RS is transmitted together with PUSCH or PUCCH, calculates a fluctuation amount of amplitude, phase or frequency of PUSCH or PUCCH signal, and a reference signal for demodulating the signal transmitted using PUSCH or PUCCH Also used as

  The DM-RS transmission band matches the PUSCH or PUCCH transmission band, but the SRS transmission band (frequency resource) is set independently of the DM-RS. That is, the SRS transmission band does not necessarily match the PUSCH or PUCCH transmission band, and is preset by the base station apparatus. In addition, the SRS can be arranged such that signals are distributed in the frequency axis direction (comb arrangement: also referred to as transmission comb). For example, the mobile station apparatus can arrange SRS signals every other subcarrier in the frequency axis direction, and the plurality of mobile station apparatuses are arranged by changing the positions of combs (for example, comb 0 and comb 1). Thus, frequency division multiple access (FDMA) can be performed on the SRS at the same transmission timing.

  Two types of channel measurement reference signals, P-SRS and A-SRS, are used for SRS. P-SRS is a reference signal for channel measurement transmitted according to a transmission cycle preset by the base station apparatus, and a subframe for transmitting P-SRS uses a radio resource control signal by the base station apparatus. Or may be set using a broadcast channel. In addition, setting information (SRS configuration) related to SRS parameters such as the P-SRS transmission period and transmission band may be included in a radio resource control signal and transmitted to the mobile station apparatus after being set in advance by the base station apparatus. good. Moreover, frequency hopping can be applied to the P-SRS in the time axis direction. P-SRS can obtain frequency diversity effect and interference averaging effect by using frequency hopping.

  A-SRS is a reference signal for channel measurement transmitted when the base station apparatus requests transmission, and a subframe for transmitting A-SRS may be set by the base station apparatus using PDCCH. It may be set using a radio resource control signal. Moreover, the sub-frame which transmits A-SRS may be set using a broadcast channel by the base station apparatus. Here, the radio resource control signal (RRC signaling) is transmitted at intervals of about 100 milliseconds to 200 milliseconds, for example.

  In addition, SRS subframes (subframes for transmitting A-SRS and P-SRS) that are subframes for transmitting SRS may be set for each cell or for each mobile station apparatus. . The same subframe may be used for the subframe which transmits A-SRS and P-SRS, and a different subframe may be used. For example, the base station apparatus may set a subframe for transmitting A-SRS for each mobile station apparatus and set a subframe for transmitting P-SRS for each cell. Here, the SRS subframe set for each cell is called a cell-specific SRS subframe, and the SRS subframe set for each mobile station device is called a mobile station device-specific SRS subframe. As another example, the base station apparatus sets a subframe for transmitting P-SRS for each cell, and sets a part of the subframe for transmitting P-SRS as a subframe for transmitting A-SRS for each cell or You may set for every mobile station apparatus.

  The physical random access channel is a physical channel used for transmitting a random access preamble and has a guard time. The PRACH is mainly used for the mobile station apparatus to synchronize with the base station apparatus, and is used for initial access, handover, reconnection request, and scheduling request.

  The scheduling request is information that the mobile station apparatus requests the base station apparatus to allocate PUSCH resources. The mobile station apparatus transmits SR when information data to be transmitted accumulates in its own buffer and requests resource allocation for PUSCH. Also, the mobile station apparatus transmits the SR to the base station apparatus using the PUCCH allocated in advance from the base station apparatus. Note that the base station apparatus allocates periodic resources for the mobile station apparatus to arrange the SR when communication connection with the mobile station apparatus starts.

(P-SRS resource allocation and frequency hopping)
FIG. 6 is a diagram illustrating a schematic configuration of P-SRS resource allocation and frequency hopping (FH). In the figure, the horizontal axis is time, and the vertical axis is frequency. The left side of the figure shows an example of resource allocation of SRS (including both types of P-SRS and A-SRS). In the example on the left side of the figure, 14 symbols are arranged in the time axis direction. Seven symbols correspond to one slot, and the length of one slot is 0.5 milliseconds (ms). Further, 14 symbols (corresponding to 2 slots) correspond to 1 subframe, and the length of 1 subframe is 1 millisecond. Thus, in the uplink signal in which one subframe is composed of 14 symbols, the SRS is arranged in the 14th symbol (also referred to as an SRS symbol). The SRS resource arranged in the 14th symbol is set in the base station apparatus according to the uplink system bandwidth and the transmission power of the mobile station apparatus. Further, the PRACH can be allocated with the bandwidth and the time symbol length being changed according to the type and format of the message to be transmitted. DM-RSs are arranged in the fourth and eleventh symbols (also referred to as DM-RS symbols) when one subframe is composed of 14 symbols, and the DM-RS transmission band is the PUSCH transmission band. Match.

  Further, in the P-SRS, frequency hopping that changes the frequency position every time it is transmitted can be applied to the time axis direction. The right side of the figure shows an example of P-SRS frequency hopping. On the right side of the figure, P-SRS is transmitted at every transmission cycle T. As shown in the figure, hopping is performed in the frequency direction every cycle T (that is, every time P-SRS is transmitted).

  Here, the P-SRS is managed by a table corresponding to the system bandwidth (for example, managed (defined) by specifications or the like), and the table is included in each of a plurality of indexes and a plurality of indexes. Composed of multiple levels. Each of the plurality of levels corresponds to the SRS transmission bandwidth.

  The base station apparatus can set the SRS transmission bandwidth for the mobile station apparatus by selecting the index and level in the table and notifying the mobile station apparatus. For example, the base station apparatus can notify the index for each cell (for each component carrier). For example, the base station apparatus can notify a level for every mobile station apparatus.

  That is, the base station apparatus notifies a common index to a plurality of mobile station apparatuses in a cell (component carrier) to be managed, and further selects and notifies one of a plurality of levels included in the index. By doing this, it is possible to set a detailed SRS transmission bandwidth for a specific mobile station apparatus. Here, the widest bandwidth among SRS transmission bandwidths corresponding to a plurality of levels included in this index is referred to as a cell (component carrier) specific SRS bandwidth.

  The base station apparatus switches the level to be notified in consideration of the channel quality (propagation state) and surplus power (Power Headroom) of the mobile station apparatus, so that the transmission bandwidth of the P-SRS to the mobile station apparatus Set. That is, the mobile station apparatus transmits an SRS related to the transmission bandwidth corresponding to the level notified by the base station apparatus. Here, the transmission bandwidth set according to the level notified by the base station apparatus is referred to as a mobile station apparatus specific SRS bandwidth.

  That is, the cell-specific SRS bandwidth is divided into a plurality of mobile station device-specific SRS bandwidths, which are present in the cell-specific SRS bandwidth (with different frequency resources (frequency positions)). From among the widths, which mobile station apparatus specific SRS bandwidth is transmitted by the mobile station apparatus is determined by a frequency domain starting position.

  Here, the frequency domain start position is information indicating the frequency resource allocation start position of the mobile station apparatus specific SRS bandwidth, and is notified by the base station apparatus. Here, the frequency domain start position may be calculated by the mobile station apparatus based on information notified from the base station apparatus (information on the frequency domain start position).

  The mobile station apparatus applies frequency hopping to the P-SRS when the hopping bandwidth, which is one of the SRS setting information, is set to a bandwidth wider than the mobile station apparatus-specific SRS transmission bandwidth. Can do.

  FIG. 5 is a diagram illustrating a schematic configuration of a transmission bandwidth of P-SRS. The P-SRS is managed in a table corresponding to the system bandwidth. For example, when an index a0 is selected from the table, the index has levels corresponding to four transmission bandwidths (for example, c0 to c3), respectively. (SRS bandwidth levels b0 to b3) are set, and when one of the levels is selected, the mobile station device specific SRS bandwidth is set to the P-SRS of the mobile station device. That is, the mobile station apparatus can set P-SRS according to the index and level of P-SRS notified from the base station apparatus. For example, when the index a0 and the level b1 are notified from the base station apparatus to the mobile station apparatus as information indicating the SRS transmission bandwidth, the mobile station apparatus sets the P-SRS transmission bandwidth to c1 based on the information. Set.

[Configuration of base station apparatus]
FIG. 1 is a block diagram showing a schematic functional configuration of a base station apparatus 1 according to the present invention. The base station apparatus 1 includes a transmission unit 101, a reception unit 103, a scheduling unit 105, an upper layer 107, a channel estimation unit 108, and an antenna 109. The transmission unit 101 includes a data control unit 1011, a modulation unit 1013, and a wireless transmission unit 1015. In addition, the reception unit 103 includes a wireless reception unit 1031, a demodulation unit 1033, and a data extraction unit 1035.

  The data control unit 1011 receives user data and control data, places control data on the PDCCH, and places transmission data and control data for the mobile station apparatus 3 on the PDSCH according to an instruction from the scheduling unit 105. The modulation unit 1013 performs signal processing such as data modulation, serial / parallel conversion of an input signal, IFFT, CP insertion, and filtering to generate a transmission signal. The radio transmission unit 1015 transmits the modulated data to the mobile station apparatus 3 via the antenna 109 after up-converting the modulated data to a radio frequency.

  The radio reception unit 1031 receives an uplink signal from the mobile station apparatus 3, down-converts the signal to a baseband signal, and outputs received data to the demodulation unit 1033. The data extraction unit 1035 confirms the correctness of the received data and notifies the scheduling unit 105 of the confirmation result. If the received data is correct, the data extraction unit 1035 separates the received data into user data and control data. The data extraction unit 1035 outputs the control data of the second layer such as downlink channel quality indication information and the success / failure of the downlink data (ACK / NACK) in the control data to the scheduling unit 105, and the other data Control data and user data of the third layer and the like are output to the upper layer 107. If the received data is incorrect, the data extraction unit 1035 stores the received data for combining with the retransmitted data, and performs a combining process when the retransmitted data is received.

  The scheduling unit 105 performs scheduling for arranging user data and control data on the PDSCH and PDCCH. Further, the scheduling unit 105 instructs the transmission unit 101 to transmit an A-SRS transmission instruction included in the PDCCH (DCI format) according to an instruction from the upper layer 107.

  The upper layer 107 includes a medium access control (MAC) layer, a radio link control (RLC) layer, a packet data convergence protocol (PDCP) layer, and a radio resource control (RRC: radio). Resource Control) layer processing. Since the upper layer 107 controls the processing units of the lower layer in an integrated manner, there is an interface between the upper layer 107, the scheduling unit 105, the channel estimation unit 108, the antenna 109, the transmission unit 101, and the reception unit 103. (However, not shown).

  The upper layer 107 includes a radio resource control unit 1071 (also referred to as a control unit). The radio resource control unit 1071 also manages various setting information, system information, paging control, communication state management of each mobile station device, mobility management such as handover, buffer status management for each mobile station device, It manages connection settings for cast and multicast bearers, manages mobile station identifiers (also referred to as UEID or RNTI (Radio Network Temporary Identifier)), and the like. In addition, the upper layer 107 exchanges information with another base station apparatus and information with an upper node. The upper layer 107 sets and manages parameters such as the mobile station device specific SRS transmission bandwidth and the frequency domain start position as SRS setting information, and includes the SRS setting information in the radio resource control signal to the mobile station device 3. The scheduling unit 105 is instructed to notify. The SRS setting information may be notified including not only the P-SRS parameters but also the A-SRS parameters. Also, the upper layer 107 instructs the scheduling unit 105 to transmit A-SRS when it is desired to perform uplink channel measurement as necessary. Also, the upper layer 107 determines the communication environment of the mobile station apparatus 3 based on the channel estimation value of the uplink signal obtained from the channel estimation unit 108, and performs optimal resource allocation for PUSCH. Further, the upper layer 107 can instruct the mobile station apparatus 3 to perform optimal A-SRS transmission in consideration of the communication environment of the mobile station apparatus 3. When the setting information of A-SRS is changed, the setting information is included in the scheduling information and output to the scheduling unit 105 in order to instruct the setting information to the mobile station apparatus 3.

  In addition, in the uplink scheduling, the scheduling unit 105 estimates the uplink channel state (wireless channel state) output from the channel estimation unit 108, requests for resource allocation from the mobile station device 3, Uplink transport format (transmission form, ie, physical resource block allocation and modulation scheme and code) for modulating each data based on usable PRB information, scheduling information input from higher layer 107, etc. Scheduling information used for uplink selection scheduling and uplink scheduling. The scheduling information used for the uplink scheduling is output to the data control unit 1011. Also, when the upper layer 107 is instructed to transmit A-SRS, the scheduling information is reset and output to the data control unit 1011.

  In addition, the scheduling unit 105 maps the downlink logical channel input from the higher layer 107 to the transport channel and outputs it to the data control unit 1011. In addition, the scheduling unit 105 processes the control data and the transport channel acquired in the uplink input from the data extraction unit 1035 as necessary, maps them to the uplink logical channel, and outputs them to the upper layer 107. To do.

  Channel estimation section 108 estimates an uplink channel state from the demodulation reference signal for demodulation of uplink data, and outputs the estimation result to demodulation section 1033. Further, in order to perform uplink scheduling, an uplink channel state is estimated from the sounding reference signal, and the estimation result is output to the scheduling section 105.

[Configuration of mobile station device]
FIG. 2 is a block diagram showing a schematic functional configuration of the mobile station apparatus 3 of the present invention. The mobile station apparatus 3 includes a transmission unit 201, a reception unit 203, a scheduling unit 205, a reference signal generation unit 206, an upper layer 207, and an antenna 209. The transmission unit 201 includes a data control unit 2011, a modulation unit 2013, and a wireless transmission unit 2015. The reception unit 203 includes a wireless reception unit 2031, a demodulation unit 2033, and a data extraction unit 2035.

  User data and control data are input from the upper layer 207 to the data control unit 2011. The data control unit 2011 arranges the input data on the PUSCH or PUCCH according to an instruction from the scheduling unit 205. The modulation unit 2013 performs data modulation on PUSCH and PUCCH and outputs the data to the radio transmission unit 2015. The radio transmission unit 2015 inserts the modulated data and the uplink reference signal into discrete Fourier transform (DFT), subcarrier mapping, inverse fast Fourier transform (IFFT), and CP (Cyclic Prefix). Then, signal processing such as filtering is performed, a transmission signal is generated, up-converted to a radio frequency, and then transmitted to the base station apparatus 1 via the antenna 209.

  Radio receiving section 2031 receives the downlink signal from base station apparatus 1, down-converts it to a baseband signal, and outputs the received signal to demodulation section 2033. The demodulator 2033 demodulates the received data. The data extraction unit 2035 separates the received data into user data and control data. The data extraction unit 2035 outputs scheduling information, random access response messages, control data related to intermittent reception control, and other second layer control data to the scheduling unit 205 and outputs user data to the upper layer 207. In addition, the data extraction unit 2035 detects the code point of the control information included in the PDCCH (DCI format) and outputs it to the upper layer 207.

  The scheduling unit 205 analyzes the control data input from the data extraction unit 2035, generates uplink scheduling information, and performs data control to allocate user data and control data to PUSCH and PUCCH based on the scheduling information. Section 2011 is instructed.

  Further, the scheduling unit 205 includes a reference signal control unit 2051. The reference signal control unit 2051 extracts SRS setting information based on the scheduling information transmitted from the base station apparatus 1. Also, transmission control is performed when SRS and PUSCH or PUCCH occur at the same timing, and SRS transmission control information is generated. The reference signal control unit 2051 outputs the SRS setting information and the SRS transmission control information to the reference signal generation unit 206. Here, the SRS setting information is information for setting parameters such as a mobile station device specific SRS transmission bandwidth, a frequency domain start position, and a transmission cycle. The SRS transmission control information is information indicating an SRS transmission control method when the SRS and other uplink channels (PUSCH, PUCCH) are allocated to the same subframe. For example, when SRS and PUCCH occur in the same subframe, this is information for instructing the mobile station apparatus 3 to perform a process of not transmitting SRS.

  In uplink scheduling, the scheduling unit 205 determines the uplink buffer status input from the higher layer 207 and uplink scheduling information (transport format and HARQ retransmission) from the base station apparatus 1 input from the data extraction unit 207. Information), and scheduling information for mapping the uplink logical channel input from the upper layer 207 to the transport channel and the uplink scheduling based on the scheduling information input from the upper layer 208, etc. Scheduling information to be generated is generated. Note that the information notified from the base station apparatus 1 is used for the uplink transport format. The scheduling information is output to the data control unit 2011.

  In addition, the scheduling unit 205 maps the uplink logical channel input from the higher layer 207 to the transport channel and outputs it to the data control unit 2011. The scheduling unit 205 also outputs the CSI, CQI, PMI, RI, and CRC check confirmation results input from the data extraction unit 207 input from the channel estimation unit 208 to the data control unit 2011. . In addition, the scheduling unit 205 processes the control data and the transport channel acquired in the downlink input from the data extraction unit 2035 as necessary, maps them to the downlink logical channel, and outputs them to the upper layer 207. To do.

  Channel estimation section 208 estimates the downlink channel state from DL-RS for downlink data demodulation, and outputs the estimation result to demodulation section 2033. Also, the channel estimation unit 208 notifies the base station apparatus 1 of the downlink channel state (radio channel state, CSI, CQI, PMI, RI) estimation result from the downlink reference signal to the downlink channel. The state is estimated, and the estimation result is output to the scheduling unit 205 as, for example, CSI, CQI, PMI, or RI.

  The reference signal generation unit 206 generates SRS (A-SRS, P-SRS) based on the SRS setting information and the SRS transmission control information input from the reference signal control unit 2051, and outputs them to the radio transmission unit 2015.

  The upper layer 207 includes a medium access control (MAC) layer, a radio link control (RLC) layer, a packet data convergence protocol (PDCP) layer, and a radio resource control (RRC: radio). Resource Control) layer processing. Since the upper layer 207 controls the processing units of the lower layer in an integrated manner, there is an interface between the upper layer 207, the scheduling unit 205, the channel estimation unit 208, the antenna 209, the transmission unit 201, and the reception unit 203. (However, not shown).

  The upper layer 207 has a radio resource control unit 2071 (also referred to as a control unit). The radio resource control unit 2071 manages various setting information, system information, paging control, communication status management of the local station, mobility management such as handover, buffer status management, unicast and multicast bearer connection setting management The mobile station identifier (UEID) is managed. In addition, the upper layer 207 extracts SRS setting information from the radio resource control signal transmitted from the base station apparatus 1 and sets SRS parameters. Further, when an A-SRS transmission instruction is included from the received DCI format, the scheduling information considering the A-SRS transmission is reset and output to the scheduling unit 205. Further, upper layer 207 sets A-SRS in accordance with an A-SRS transmission instruction from base station apparatus 1 and outputs the A-SRS to scheduling section 205 as scheduling information.

<Embodiment>
Embodiments of the present invention will be described below. In the embodiment of the present invention, the base station apparatus notifies the mobile station apparatus of an uplink grant including frequency resource allocation information of the physical uplink shared channel and a sounding reference signal transmission instruction. When the notified uplink grant includes a sounding reference signal transmission instruction, the mobile station apparatus sets the sounding reference signal resource according to the information on the physical uplink shared channel resource allocation, and sets the sounding reference signal. Transmit to the base station device. Here, the frequency resource allocation information includes the frequency allocation position. Note that the frequency resource bandwidth and the start position of the frequency resource may be indicated as PUSCH frequency resource allocation information.

  In the embodiment of the present invention, the base station apparatus 1 determines the PUSCH resource to be allocated to the mobile station apparatus 3 from the estimation result of the channel state notified from the mobile station apparatus 3 or the surplus power report (PHR: Power Headroom Reporting). To do. In order to instruct PUSCH transmission, the base station apparatus 1 uses an uplink grant. At this time, in order to perform uplink channel measurement, the base station apparatus 1 may instruct transmission of A-SRS. Regarding re-setting (changing, switching) of A-SRS parameters, when the base station apparatus 1 performs re-setting using radio resource control signals (RRC signaling) as in the prior art, changing the parameters of A-SRS And A-SRS transmission instructions cause a time difference, and dynamic communication cannot be performed. Here, dynamic communication means communication in which signals are transmitted and received using parameters suitable for each subframe. In addition, when a control information field related to A-SRS parameters is added to an uplink grant in order to perform dynamic reconfiguration, the size of the uplink grant itself increases, and different types of downlink control information formats and When the sizes become equal, the mobile station device 3 cannot recognize whether the received signal is an uplink grant or another downlink control information format. Further, even if the sizes of different types of downlink control information formats are not equal, when the size of the uplink grant increases, in order to satisfy the required quality related to reception of the uplink grant in the mobile station device 3, The base station apparatus 1 needs to increase the transmission power used for uplink grant transmission, and there is a problem that an increase in transmission power causes an increase in other cell interference. In addition, when the base station apparatus 1 does not increase the total transmission power, in order to use sufficient transmission power for the PDCCH including the uplink grant including the control information field related to the A-SRS parameter, transmission is performed in the same subframe. Therefore, there is a problem that the transmission power of other PDCCHs to be reduced needs to be reduced, and the quality of the PDCCHs for which the transmission power is reduced is deteriorated. Therefore, by associating the control information for setting the PUSCH parameters included in the uplink ring grant with the A-SRS parameters, the A-SRS parameters can be dynamically reset, and the efficiency can be improved. Communication can be performed.

  In the embodiment of the present invention, the base station apparatus 1 sets PUSCH frequency resource allocation (frequency resource, frequency band) in consideration of the channel state and surplus power notified from the mobile station apparatus 3. The mobile station apparatus 3 performs A-SRS resource allocation from the PUSCH frequency resource allocation information included in the uplink grant notified from the base station apparatus 1. Note that the PUSCH frequency resource allocation information includes a transmission bandwidth. Also, the frequency resource allocation start position is included in the PUSCH frequency resource allocation information.

  That is, the mobile station apparatus 3 that has received an uplink grant including an A-SRS transmission instruction and PUSCH frequency resource allocation information from the base station apparatus 1 transmits the PUSCH to the base station apparatus according to the PUSCH frequency resource allocation information. Send. For example, the mobile station apparatus 3 transmits the PUSCH to the base station apparatus in a subframe after a predetermined time (for example, after 4 subframes) from the subframe that has received the uplink grant.

  Furthermore, mobile station apparatus 3 transmits A-SRS to base station apparatus 1 in accordance with an A-SRS transmission instruction and PUSCH frequency resource allocation information (sometimes referred to as out-of-band A-SRS). At this time, the mobile station device 3 selects a frequency resource region for transmitting the A-SRS according to the PUSCH frequency resource allocation information, and transmits the A-SRS related to the selected frequency resource region to the base station device 1. . That is, the mobile station device 3 selects a frequency resource region including the PUSCH frequency resource allocated by the PUSCH frequency resource allocation information, and transmits an A-SRS related to the selected frequency resource region to the base station device 1. For example, the mobile station device 3 transmits an A-SRS related to the selected frequency resource region to the base station device 1 in the SRS subframe closest to the subframe that has received the uplink grant. In addition, according to the frequency resource allocation information of PUSCH, the allocation start position of the frequency resource region for transmitting A-SRS may be indicated.

  In the embodiment of the present invention, A-SRS frequency resource allocation is associated with PUSCH frequency resource allocation information. Information (control information field and information bits) for setting the A-SRS frequency resource in the uplink grant is obtained by associating the PUSCH frequency resource allocation information included in the uplink grant with the A-SRS frequency resource. The frequency resource of A-SRS can be dynamically changed without adding.

  FIG. 3 is a diagram illustrating a frequency resource region of A-SRS. When the uplink grant includes an A-SRS transmission instruction, the mobile station apparatus 3 performs A-SRS resource allocation in consideration of PUSCH frequency resource allocation. In FIG. 3, the frequency resource of A-SRS is composed of a plurality of frequency resources for A-SRS transmission (A-SRS1 to A-SRS5) obtained by dividing the system bandwidth into a plurality of parts (for example, five parts). (Figure (a)). The mobile station device 3 allocates PUSCH frequency resources from the PUSCH frequency resource allocation information included in the uplink grant, and further, when the uplink grant includes an A-SRS transmission instruction, The base station selects an A-SRS frequency resource (A-SRS2 in FIG. 2B and A-SRS4 in FIG. 2C) including the PUSCH frequency resource from the A-SRS frequency resources. The selected A-SRS is transmitted to the device 1. In other words, the mobile station device 3 uses, as a frequency resource for A-SRS, a frequency resource for A-SRS transmission in which PUSCH frequency resources overlap among a plurality of pre-configured frequency resources for A-SRS transmission. Set. When the PUSCH frequency resource is only partially included in the A-SRS frequency resource as shown in FIG. 6D, the A-SRS frequency resource with the highest frequency resource is selected (FIG. 4D). Then, A-SRS3). Here, the frequency resource of A-SRS (or the number of divisions for setting the A-SRS frequency resource) may be uniquely set in advance by the system, or from the base station apparatus 1 to the mobile station apparatus as broadcast information 3 may be notified all at once, or may be notified from the base station device 1 to the individual mobile station devices 3.

  When the PUSCH frequency resource spans multiple A-SRS frequency resource regions ((e) in the figure), all the A-SRS frequency resources including the PUSCH frequency resource are transmitted to the base station apparatus 1. Alternatively, a part of the plurality of A-SRS frequency resources may be transmitted to the base station apparatus 1.

  Moreover, the frequency resource area | region of A-SRS can also be set by reusing the setting information of P-SRS. For example, depending on the PUSCH transmission bandwidth included in the PUSCH frequency resource allocation information, the mobile station apparatus specific SRS bandwidth closest to the PUSCH transmission bandwidth from among the cell specific SRS bandwidth (SRS bandwidth index) (SRS bandwidth level) is selected, and the frequency domain start position including the PUSCH frequency resource is selected. That is, the mobile station device 3 selects an SRS transmission bandwidth level according to the PUSCH transmission bandwidth, selects a frequency region start position indicating an SRS region including the PUSCH frequency resource, and generates an A-SRS. To do.

  In the embodiment of the present invention, it is possible to dynamically change the A-SRS frequency resource allocation by associating the PUSCH frequency resource allocation information included in the uplink grant with the A-SRS frequency resource allocation. It becomes.

  When the PUSCH frequency resource is frequency hopped between slots, the mobile station apparatus 3 may arrange the A-SRS frequency resource in accordance with the PUSCH frequency resource arranged in the first slot. The frequency resource of A-SRS may be arranged according to the frequency resource of PUSCH arranged in the second slot, or the frequency resource of A-SRS is set so as to cover the frequency hopping region of the frequency resource of PUSCH. It may be arranged. The frequency resource allocation method of A-SRS when PUSCH frequency hops may be uniquely determined in advance by the system, or may be notified simultaneously from the base station apparatus 1 to the mobile station apparatus 3 as broadcast information. The base station apparatus 1 may notify the individual mobile station apparatus 3.

  FIG. 4 is a diagram illustrating an example of a DCI format including an A-SRS transmission instruction according to the embodiment of the present invention. In the DCI format (uplink grant) shown in FIG. 6A, from which uplink component carrier the uplink signal is transmitted (to which uplink component carrier the PUSCH scheduled by the DCI format is arranged) ) Carrier indicator (CI) information, PDCCH format identification (Flag for format 0 / format 1A differentiation) information, frequency hopping flag (Frequency hopping flag), resource block allocation and hopping resource allocation (Resource block assignment and hopping) resource allocation) information (also referred to as PUSCH frequency resource allocation information), modulation and coding scheme and redundancy version information, NDI (New Data Indicator) information, schedule Transmission power control command (TPC command for scheduled PUSCH) information for the transmitted PUSCH, cyclic shift for DM-RS (Cyclic shift for DM-RS) information, CQI transmission instruction (CQI request: also called CQI request) information, Padding bit (0 padding) information, Cyclic Redundancy Check (CRC) information, A-SRS transmission instruction (defined by, for example, 1 bit defined to instruct transmission of A-SRS) (SRS activation, SRS request, trigger for SRS transmission) information.

  In FIG. 4A, when the field of A-SRS transmission instruction information is included in the uplink grant, the mobile station device 3 transmits the A-SRS to the base station device 1. That is, when the field defined for A-SRS transmission instruction included in the uplink grant is set to a predetermined value (for example, “1”), the mobile station device 3 The A-SRS is transmitted to the base station apparatus 1.

  FIG. 5B shows an A-SRS transmission instruction method when the A-SRS transmission instruction information field is not included in the DCI format. In FIG. 5B, when the frequency hopping flag and the padding bit information are a predetermined code point (predetermined value), the mobile station apparatus 3 recognizes that an A-SRS transmission instruction has been notified, and A-SRS is transmitted to the station apparatus 1.

  Also, in the figure, when the CQI transmission instruction included in the uplink grant is also set (for example, the CQI request is set to “1”), the mobile station apparatus 3 uses the CQI and A− SRS is transmitted to the base station apparatus 1 in the same subframe. Here, the mobile station apparatus 3 arranges CQI and UL-SCH data (transport link for Uplink Shared Channel data, UL-SCH) in the PUSCH, and sends it to the base station apparatus 1 in the same subframe together with the A-SRS. Send.

  Here, the cyclic shift applied to the A-SRS may be the same as the cyclic shift applied to the P-SRS, may be uniquely determined in advance by the system, or may be base information as broadcast information. 1 may be notified to the mobile station apparatus 3 all at once, or may be notified from the base station apparatus 1 to the individual mobile station apparatuses 3. In addition, the cyclic shift applied to the A-SRS is associated with parameters applied to the cyclic shift of the DM-RS (for example, the cyclic shift index of the DM-RS, the cyclic shift information of the DM-RS). The obtained value may be applied, the same value may be applied, or the cyclic shift of A-SRS and DM-RS may be managed in a predetermined table. That is, the base station apparatus 1 can set the A-SRS cyclic shift in association with the parameters applied to the DM-RS cyclic shift, and the mobile station apparatus 3 is applied to the DM-RS. The cyclic shift applied to the A-SRS can be set (derived) uniformly (mechanically or automatically) from the parameters.

  Further, parameters such as the transmission cycle of A-SRS may be the same as those of P-SRS, may be uniquely determined in advance by the system, or mobile station apparatus from base station apparatus 1 as broadcast information 3 may be notified all at once, or may be notified from the base station device 1 to the individual mobile station devices 3. In addition, when the base station apparatus 1 sets the number of A-SRS transmissions and a transmission timer in advance and notifies the mobile station apparatus 3 using a radio resource control signal or the like, the mobile station apparatus 3 The A-SRS is transmitted to the base station apparatus 1 until the transmission timer reaches expiration.

  Also, in the present invention, when an A-SRS transmission instruction is included in a DCI format including a CQI transmission instruction, the mobile station apparatus 3 uses the same subframe for the CQI and A-SRS in the base station apparatus 1. Or may be transmitted in different subframes.

  Further, in the present invention, the base station apparatus 1 can set PUSCH frequency resource allocation information in consideration of A-SRS resource allocation.

  In the present invention, when communication is performed using a plurality of uplink component carriers, the A-SRS parameters may be set for each uplink component carrier or may be set for each mobile station apparatus. good.

  According to the present invention, the mobile station apparatus 3 sets A-SRS resource allocation (resource allocation) according to PUSCH resource allocation information included in the uplink grant. The base station device 1 can communicate with the communication environment (including communication quality, channel quality, communication state, channel state, and radio propagation path state) and the position of the mobile station device 3 (for example, cell center (cell center) or cell edge (cell edge)). ) Since the PUSCH resource allocated to the mobile station apparatus 3 is changed according to the number of mobile station apparatuses allocated to the cell, the A-SRS resource can be dynamically changed accordingly.

  In addition, you may make it implement | achieve a part of function of the base station apparatus 1 and the mobile station apparatus 3 in embodiment mentioned above with a computer. In that case, the program for realizing the control function may be recorded on a computer-readable recording medium, and the program recorded on the recording medium may be read into a computer system and executed. Here, the “computer system” includes an OS and hardware such as peripheral devices. The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. Furthermore, “computer-readable recording medium” means that a program is held dynamically 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. It is also possible to include one that holds a program for a certain time, such as a volatile memory inside a computer system that becomes a server or client in that case. The program may be a program for realizing a part of the functions described above, and may be a program capable of realizing the functions described above in combination with a program already recorded in a computer system.

  Moreover, you may implement | achieve part or all of the mobile station apparatus 3 in the embodiment mentioned above and the base station apparatus 1 as LSI (Large Scale Integration) which is typically an integrated circuit. Each functional block of the mobile station device 3 and the base station device 1 may be individually chipped, or a part or all of them may be integrated into a chip. Further, the method of circuit integration is not limited to LSI, and may be realized by a dedicated circuit or a general-purpose processor. In addition, when an integrated circuit technology that replaces LSI appears due to progress in semiconductor technology, an integrated circuit based on the technology can also be used.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and the design and the like within the scope not departing from the gist of the present invention are also claimed. Included in the range.

DESCRIPTION OF SYMBOLS 1 Base station apparatus 3 Mobile station apparatus 101 Transmitter (base station side transmitter)
103 Receiver (base station side receiver)
105 Scheduling section 107 Upper layer 108 Channel estimation section 109 Antenna 201 Transmitting section (mobile station side transmitting section)
203 Receiving unit (receiving unit on the mobile station side)
205 Scheduling unit 206 Reference signal generation unit 207 Upper layer 208 Channel estimation unit 209 Antenna 1011 Data control unit 1013 Modulation unit 1015 Radio transmission unit 1031 Radio reception unit 1033 Demodulation unit 1035 Data extraction unit 1071 Radio resource control unit 2011 Data control unit 2013 Modulation Unit 2015 wireless transmission unit 2031 wireless reception unit 2033 demodulation unit 2035 data extraction unit 2051 reference signal control unit 2071 radio resource control unit

Claims (16)

A wireless communication system in which a base station device and a mobile station device perform wireless communication,
The base station device
Notifying the mobile station apparatus of an uplink grant including frequency resource allocation information of a physical uplink shared channel and a sounding reference signal transmission instruction;
The mobile station device
When the notified uplink grant includes an instruction to transmit the sounding reference signal, the sounding reference signal resource is set according to information on resource allocation of the physical uplink shared channel,
The wireless communication system, wherein the sounding reference signal is transmitted to the base station apparatus. The mobile station device
The radio communication system according to claim 1, wherein the frequency resource of the sounding reference signal is set according to frequency resource allocation information of the physical uplink shared channel. The mobile station device
Among the plurality of pre-configured frequency resources for the sounding reference signal, the frequency resource for the sounding reference signal that overlaps the frequency resource of the physical uplink shared channel is set as the resource of the sounding reference signal. The wireless communication system according to claim 2. The mobile station device
When the frequency resource of the physical uplink shared channel overlaps with a plurality of frequency resources for the sounding reference signal, the frequency resource for the sounding reference signal with the most overlapping frequency resource of the physical uplink shared channel is The radio communication system according to claim 3, wherein the radio communication system is set to a resource of a sounding reference signal. A mobile station device that performs radio communication with a base station device,
Means for receiving an uplink grant notified from the base station device;
Means for setting the resource of the sounding reference signal according to the information on the resource allocation of the physical uplink shared channel when the uplink grant includes a sounding reference signal transmission instruction;
And a means for transmitting the sounding reference signal to the base station apparatus. The mobile station device
The mobile station apparatus according to claim 5, further comprising: means for setting a frequency resource of the sounding reference signal according to frequency resource allocation information of the physical uplink shared channel. The mobile station device
At least means for setting a frequency resource for the sounding reference signal in which a frequency resource of the physical uplink shared channel overlaps among a plurality of pre-configured frequency resources for the sounding reference signal as a resource of the sounding reference signal The mobile station apparatus according to claim 6, further comprising: The mobile station device
When the frequency resource of the physical uplink shared channel overlaps with a plurality of frequency resources for the sounding reference signal, the frequency resource for the sounding reference signal with the most overlapping frequency resource of the physical uplink shared channel is The mobile station apparatus according to claim 7, comprising at least means for setting a resource of a sounding reference signal. A wireless communication method in which a base station device and a mobile station device perform wireless communication,
The base station device
Notifying the mobile station device of an uplink grant including frequency resource allocation information of a physical uplink shared channel and a sounding reference signal transmission instruction;
The mobile station device
When the notified uplink grant includes a transmission instruction for the sounding reference signal, setting a sounding reference signal resource according to information on resource allocation of the physical uplink shared channel; and
Transmitting at least the sounding reference signal to the base station apparatus. A wireless communication method, comprising: The mobile station device
The radio communication method according to claim 9, comprising at least a step of setting a frequency resource of the sounding reference signal according to frequency resource allocation information of the physical uplink shared channel. The mobile station device
At least a step of setting a frequency resource for the sounding reference signal in which a frequency resource of the physical uplink shared channel overlaps among a plurality of pre-configured frequency resources for the sounding reference signal as a resource of the sounding reference signal The wireless communication method according to claim 10, further comprising: The mobile station device
When the frequency resource of the physical uplink shared channel overlaps with a plurality of frequency resources for the sounding reference signal, the frequency resource for the sounding reference signal with the most overlapping frequency resource of the physical uplink shared channel is The wireless communication method according to claim 11, further comprising: setting at least a resource of the sounding reference signal. An integrated circuit that, when mounted on a mobile station device, causes the mobile station device to perform a plurality of functions,
A function of receiving an uplink grant notified from the base station apparatus;
When the uplink grant includes a sounding reference signal transmission instruction, the function of setting the resource of the sounding reference signal according to the information on resource allocation of the physical uplink shared channel,
A function of transmitting the sounding reference signal to the base station apparatus, causing the mobile station apparatus to exhibit the function. In the mobile station device,
14. The integrated circuit according to claim 13, wherein the mobile station apparatus has a function of setting a frequency resource of the sounding reference signal according to frequency resource allocation information of the physical uplink shared channel. In the mobile station device,
The function of setting the frequency resource for the sounding reference signal, in which the frequency resource of the physical uplink shared channel overlaps, among the plurality of frequency resources for the sounding reference signal configured in advance, as the resource of the sounding reference signal The integrated circuit according to claim 14, wherein the integrated circuit is exhibited by a mobile station device. In the mobile station device,
When the frequency resource of the physical uplink shared channel overlaps with a plurality of frequency resources for the sounding reference signal, the frequency resource for the sounding reference signal with the most overlapping frequency resource of the physical uplink shared channel is The integrated circuit according to claim 15, wherein the mobile station apparatus has a function of setting a resource of a sounding reference signal.