JP2012034145A - Mobile communication system, base station apparatus, mobile station apparatus, and communication method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mobile communication system and a communication method capable of performing efficient scheduling by a base station apparatus in the case where the base station apparatus and a mobile station apparatus carry out transmitting/receiving of a physical channel via a single antenna port or multi-antenna ports.SOLUTION: In a mobile communication system comprising a base station apparatus and a mobile station apparatus, said base station apparatus notifies said mobile station apparatus of a downlink control information format including information instructing a single antenna port transmission or multi-antenna transmission for a sounding reference signal, and said mobile station apparatus transmits, to said base station apparatus, a sounding reference signal for a single antenna port or multi-antennas in accordance with said information.

Description

  The present invention relates to a mobile communication system and a communication method including a base station device and a mobile station device.

  The 3rd Generation Partnership Project (3GPP) examines and creates specifications for mobile communication systems based on networks developed from W-CDMA (Wideband-Code Division Multiple Access) and GSM (Global System for Mobile Communications). It is a project. In 3GPP, the W-CDMA system is standardized as a third generation cellular mobile communication system, and services are started sequentially. In addition, HSDPA (High-speed Downlink Packet Access), which further increases the communication speed, has been standardized and a service has been started. 3GPP uses the evolution of third generation radio access technology (hereinafter also referred to as “LTE (Long Term Evolution)” or “EUTRA (Evolved Universal Terrestrial Radio Access)”) and a wider frequency band, Further, studies on mobile communication systems (hereinafter, also referred to as “LTE-A (Long Term Evolution-Advanced)” or “Advanced-EUTRA”) that realize high-speed data transmission / reception are in progress.

  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-precoded). The introduction of a method (also called OFDM) is under consideration. 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 mobile communication system is continuous, whereas a plurality of continuous and / or discontinuous frequency bands (hereinafter referred to as “component carrier (CC)”). Alternatively, it is proposed to use a composite frequency band (also referred to as “Carrier Component”) and operate as one wide frequency band (also referred to as carrier aggregation). . Also, in order for the base station apparatus and the mobile station apparatus to communicate using a wider frequency band more flexibly, the frequency band used for downlink communication and the frequency band used for uplink communication are different. It has also been proposed to use a frequency bandwidth (Asymmetric carrier aggregation) (Non-patent Document 1).

  FIG. 6 is a diagram for explaining a mobile communication system in which frequency bands are aggregated in the prior art. It is symmetric that the frequency band used for downlink (DL) communication and the frequency band used for uplink (UL) communication as shown in FIG. It is also called frequency band aggregation (Symmetric carrier aggregation). As shown in FIG. 6, 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. 6, 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 having a 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. 6, each downlink component carrier has a downlink channel such as a physical downlink control channel (hereinafter referred to as PDCCH) or a physical downlink shared channel (hereinafter referred to as PDSCH). Be placed.

  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 downlink transport block is transmitted to the mobile station apparatus using PDSCH. Here, in FIG. 6, the base station apparatus can transmit up to five downlink transport blocks (PDSCH) to the mobile station apparatus in the same subframe.

  Each uplink component carrier is provided with an uplink channel such as a physical uplink control channel (hereinafter referred to as PUCCH) or a physical uplink shared channel (hereinafter referred to as PUSCH). The

  The mobile station apparatus uses PUCCH and / or PUSCH to indicate channel state information (CSI: Channel Statement information) indicating the channel state of the downlink 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. 6, the mobile station apparatus can transmit up to 5 uplink transport blocks (or PUSCH) to the base station apparatus in the same subframe.

  Here, the mobile station apparatus transmits a sounding reference signal (hereinafter also referred to as SRS: Sounding Reference Signal) to the base station apparatus using the uplink in order for the base station apparatus to measure the uplink channel. can do. In LTE-A, a mobile station apparatus transmits periodic SRS (hereinafter also referred to as P-SRS: Periodic SRS) to a base station apparatus, and in addition, a non-periodic SRS (hereinafter referred to as A-SRS). : Aperiodic SRS, Dynamic SRS, and Scheduled SRS) are also being considered for transmission to the base station apparatus.

  For example, the mobile station apparatus transmits P-SRS to the base station apparatus in accordance with an instruction from the base station apparatus. For example, the mobile station apparatus transmits A-SRS to the base station apparatus in accordance with an instruction from the base station apparatus. The base station apparatus schedules the mobile station apparatus based on P-SRS and A-SRS transmitted from the mobile station apparatus, and determines, for example, PUSCH resource allocation, modulation scheme to be applied to the PUSCH, and coding rate. be able to.

  In LTE-A, it is proposed that a mobile station apparatus transmits SRS for a single antenna port and SRS for a multi-antenna port to a base station apparatus. For example, the mobile station apparatus performs A-SRS for the multi-antenna port according to the downlink control information format (DCI format, uplink grant: UL grant, uplink assignment: Uplink assignment) from the base station apparatus. Transmission to a base station apparatus has been proposed (Non-Patent Document 2).

"Carrier aggregation in LTE-Advanced", 3GPP TSG RAN WG1 Meeting # 53bis, R1-082464, June 30-July 4, 2008. "Periodic SRS for Multi-antenna Transmission", 3GPP TSG RAN1 Meeting # 61bis, R1-104031, June28-July2, 2010.

  However, in the conventional technology, the mobile station apparatus cannot dynamically switch SRS transmission for a single antenna port and SRS transmission for a multi-antenna port.

  When transmitting and receiving physical channels, the base station apparatus and mobile station apparatus perform transmission and reception while dynamically switching between single antenna port transmission and multi-antenna port transmission. However, since the mobile station apparatus cannot dynamically switch between SRS transmission for a single antenna port and SRS transmission for a multi-antenna port, the base station apparatus can perform efficient scheduling adapted to the channel state. It will disappear.

  That is, the conventional technique has a problem that when the base station apparatus and the mobile station apparatus transmit and receive physical channels using a single antenna port or a multi-antenna port, the base station apparatus cannot perform efficient scheduling.

  The present invention has been made in view of such circumstances, and when the base station apparatus and the mobile station apparatus transmit and receive a physical channel through a single antenna port or a multi-antenna port, the base station apparatus efficiently A mobile communication system and a communication method capable of performing scheduling are provided.

  (1) In order to achieve the above object, the present invention takes the following measures. That is, the mobile communication system of the present invention is a mobile communication system including a base station apparatus and a mobile station apparatus, and the base station apparatus instructs single antenna port transmission or multi-antenna port transmission for a sounding reference signal. A downlink control information format including information is notified to the mobile station device, and the mobile station device transmits a sounding reference signal for a single antenna port or a multi-antenna port to the base station device according to the information. Yes.

  (2) Further, in the mobile communication system including a base station device and a mobile station device, the base station device has a downlink control information format including information instructing single antenna port transmission for a sounding reference signal. The mobile station apparatus notifies the mobile station apparatus, and the mobile station apparatus transmits a sounding reference signal for a single antenna port to the base station apparatus according to the information.

  (3) Further, in the mobile communication system including a base station device and a mobile station device, the base station device has a downlink control information format including information instructing multi-antenna port transmission for a sounding reference signal. The mobile station apparatus notifies the mobile station apparatus, and the mobile station apparatus transmits a sounding reference signal for a multi-antenna port to the base station apparatus according to the information.

  (4) Further, in the mobile communication system including a base station device and a mobile station device, the base station device notifies the mobile station device of downlink control information including a sounding reference signal transmission instruction, The mobile station apparatus transmits a sounding reference signal for a single antenna port or a multi-antenna port to the base station apparatus in accordance with the format of the downlink control information.

  (5) Further, in the mobile communication system including a base station device and a mobile station device, the base station device notifies the mobile station device of a downlink control information format including a sounding reference signal transmission instruction. The mobile station apparatus transmits a sounding reference signal for a single antenna port to the base station apparatus when the downlink control information format includes an instruction to transmit the sounding reference signal, and performs the downlink control. The information format is characterized in that the mobile station apparatus is used only for transmitting a physical uplink shared channel through a single antenna port.

  (6) Further, in the mobile communication system including a base station device and a mobile station device, the base station device notifies the mobile station device of a downlink control information format including a sounding reference signal transmission instruction. When the downlink control information format includes an instruction to transmit the sounding reference signal, the mobile station device transmits a sounding reference signal for a multi-antenna port to the base station device, and the downlink control The information format is characterized in that the mobile station apparatus is used for transmitting a physical uplink shared channel through a multi-antenna port.

  (7) Further, the mobile communication system includes a base station apparatus and a mobile station apparatus, wherein the base station apparatus includes a first downlink control information format including a sounding reference signal transmission instruction or a second downlink control information format. Link control information format is notified to the mobile station device, and the mobile station device, when the first downlink control information format includes a transmission instruction for the sounding reference signal, When a reference signal is transmitted to the base station apparatus and the second downlink control information format includes an instruction to transmit the sounding reference signal, a sounding reference signal for a multi-antenna port is transmitted to the base station apparatus. Send The first downlink control information format is used only for the mobile station apparatus to transmit a physical uplink shared channel through a single antenna port, and the second downlink control information format is used for the mobile station apparatus. Is used to transmit a physical uplink shared channel through a multi-antenna port.

  (8) Moreover, it is the base station apparatus in the mobile communication system comprised from a base station apparatus and a mobile station apparatus, Comprising: The downlink control information containing the information which instruct | indicates single antenna port transmission with respect to a sounding reference signal or multi-antenna port transmission Means is provided for notifying the mobile station apparatus of the format.

  (9) Further, downlink control information including information instructing single antenna port transmission or multi-antenna port transmission for a sounding reference signal, in a mobile station apparatus in a mobile communication system including a base station apparatus and a mobile station apparatus Means for notifying the format by the base station apparatus, and means for transmitting a sounding reference signal for a single antenna port or a multi-antenna port to the base station apparatus according to the information.

  (10) A mobile station apparatus in a mobile communication system including a base station apparatus and a mobile station apparatus, wherein the base station apparatus is notified of downlink control information including a sounding reference signal transmission instruction. In accordance with the format of the downlink control information, a sounding reference signal for a single antenna port or a multi-antenna port is transmitted to the base station apparatus.

  (11) A mobile station apparatus in a mobile communication system including a base station apparatus and a mobile station apparatus, wherein the first downlink control information format or the second downlink control includes a sounding reference signal transmission instruction. Means for notifying an information format by the base station apparatus, and if the first downlink control information format includes a transmission instruction for the sounding reference signal, a sounding reference signal for a single antenna port is transmitted to the base station. Means for transmitting to the station apparatus, and if the second downlink control information format includes a transmission instruction for the sounding reference signal, the sounding reference signal for the multi-antenna port is transmitted to the base station apparatus. And the first downlink control information format is used only for the mobile station apparatus to transmit a physical uplink shared channel through a single antenna port, and the second downlink control information format is provided. The information format is characterized in that the mobile station apparatus is used for transmitting a physical uplink shared channel through a multi-antenna port.

  (12) Further, a communication method of a base station apparatus in a mobile communication system including a base station apparatus and a mobile station apparatus, and including a downlink including information instructing single antenna port transmission or multi-antenna port transmission for a sounding reference signal The mobile station apparatus is notified of the link control information format.

  (13) A mobile station apparatus communication method in a mobile communication system composed of a base station apparatus and a mobile station apparatus, wherein the mobile station apparatus includes a downlink including information instructing single antenna port transmission or multi-antenna port transmission for a sounding reference signal. A link control information format is notified by the base station apparatus, and a sounding reference signal for a single antenna port or a multi-antenna port is transmitted to the base station apparatus according to the information.

  (14) A mobile station apparatus communication method in a mobile communication system including a base station apparatus and a mobile station apparatus, wherein downlink control information including a sounding reference signal transmission instruction is notified from the base station apparatus. In accordance with the format of the downlink control information, a sounding reference signal for a single antenna port or a multi-antenna port is transmitted to the base station apparatus.

  (15) A mobile station apparatus communication method in a mobile communication system including a base station apparatus and a mobile station apparatus, wherein the first downlink control information format including a sounding reference signal transmission instruction or the second When a downlink control information format is notified by the base station apparatus and the first downlink control information format includes an instruction to transmit the sounding reference signal, a sounding reference signal for a single antenna port is transmitted to the base station. When the second downlink control information format includes the sounding reference signal transmission instruction, the sounding reference signal for the multi-antenna port is transmitted to the base station device. The first downlink control information format is used for the mobile station apparatus to transmit a physical uplink shared channel through a single antenna port, and the second downlink control information format is the mobile station apparatus. Is used to transmit a physical uplink shared channel through a multi-antenna port.

  According to the present invention, when a base station apparatus and a mobile station apparatus transmit and receive a physical channel using a single antenna port or a multi-antenna port, the base station apparatus can perform efficient scheduling.

It is a figure which shows notionally the structure of the physical channel which concerns on embodiment of this invention. It is a block diagram which shows schematic structure of the base station apparatus which concerns on embodiment of this invention. It is a block diagram which shows schematic structure of the mobile station apparatus which concerns on embodiment of this invention. It is a figure which shows the example of transmission of SRS in 1st Embodiment. It is a figure which shows the example of transmission of SRS in 2nd Embodiment. It is a figure which shows the example of the frequency band aggregation in a prior art.

  Next, embodiments according to the present invention will be described with reference to the drawings. FIG. 1 is a diagram illustrating a configuration example of a channel according to an embodiment of the present invention. The downlink physical channel includes a physical downlink control channel (PDCCH) and a physical downlink shared channel (PDSCH). The uplink physical channel includes a physical uplink shared channel (PUSCH) and a physical uplink control channel (PUCCH).

  In addition, the base station apparatus transmits a downlink reference signal (also referred to as a DRS: Downlink Reference Signal, a downlink pilot signal, or a downlink pilot channel) to the mobile station apparatus. In addition, the mobile station apparatus transmits an uplink reference signal (URS: Uplink Reference Signal, also referred to as an uplink pilot signal or an uplink pilot channel) to the base station apparatus. Here, the uplink reference signal mainly includes a demodulation reference signal (DRS) used by the base station apparatus to demodulate the PUCCH and / or PUSCH. The uplink reference signal mainly includes a sounding reference signal (SRS) used by the base station apparatus to estimate the uplink channel state.

  The PDCCH is a channel used for notifying (designating) a mobile station apparatus of PDSCH resource allocation, HARQ processing information for downlink data, PUSCH resource allocation, and the like. The PDCCH is composed of a plurality of control channel elements (CCEs), and the mobile station apparatus receives the PDCCH from the base station apparatus by detecting the PDCCH composed of CCEs. 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).

  In addition, a plurality of formats are defined in downlink control information (DCI) transmitted by PDCCH. Hereinafter, the format of the downlink control information is also referred to as a DCI format (DCI format).

  For example, as a DCI format for the downlink, a DCI format 1 / 1A used only for transmitting a PDSCH by one transmission antenna port (hereinafter also referred to as a single antenna port) is defined. That is, the DCI format 1 / 1A is used only for the base station apparatus to schedule one PDSCH code word (CW: Code Word). Note that the DCI format 1 / 1A may be used to transmit one PDSCH codeword using a transmission diversity scheme for PDSCH.

  Further, for example, as a DCI format for the downlink, DCI format 2 used when the base station apparatus transmits PDSCH by SM (Spatial Multiplexing) using MIMO (Multiple Input Multiple Output) is defined. Is done. Here, transmission / reception of signals (information) by SM using MIMO refers to a plurality of spatial dimension channels realized by a plurality of transmission antenna ports (multi-antenna ports) and a plurality of reception antenna ports (multi-antenna ports). On the other hand, this is a technique in which a plurality of signals (information) are multiplexed and transmitted / received.

  That is, as the DCI format for the downlink, DCI format 2 used for the base station apparatus to transmit the PDSCH through the multi-antenna port is defined. That is, DCI format 2 is used for the base station apparatus to schedule two PDSCH codewords. Here, the DCI format 2 may be used for the base station apparatus to schedule one PDSCH codeword. That is, DCI format 2 may be used for the base station apparatus to transmit PDSCH through a single antenna port.

  Further, for example, as the DCI format for the uplink, DCI format 0 that is used only for the mobile station apparatus to transmit PUSCH through a single antenna port is defined. That is, DCI format 0 is used only for the base station apparatus to schedule one PUSCH codeword.

  Further, for example, as the DCI format for the uplink, DCI format 0A used when the mobile station apparatus transmits PUSCH by SM using MIMO is defined. That is, as the DCI format for the uplink, DCI format 0A used for the mobile station apparatus to transmit PUSCH through the multi-antenna port is defined. That is, DCI format 0A is used for the base station apparatus to schedule two PUSCH codewords. Here, the DCI format 0A may be used for the base station apparatus to schedule one PUSCH codeword. That is, the DCI format 0A may be used for the mobile station apparatus to transmit the PUSCH using a single antenna port.

  Here, the antenna port indicates a logical antenna used for signal processing. That is, one transmission antenna port (single antenna port) may be configured by one physical antenna or may be configured by a plurality of physical antennas. In addition, one reception antenna port (single antenna port) may be configured by one physical antenna or may be configured by a plurality of physical antennas. Further, the plurality of transmission antenna ports (multi-antenna ports) may be configured by a plurality of physical antennas or may be configured by a plurality of physical antennas. In addition, the plurality of reception antenna ports (single antenna ports) may be configured by one physical antenna or may be configured by a plurality of physical antennas.

  For example, an (uplink) single antenna port mode is defined for a mobile station apparatus having a plurality of transmission antennas, and the operation (behavior) of the mobile station apparatus in which the (uplink) single antenna port mode is defined is From the station apparatus side, it is assumed to be the same as the operation (behavior) of a mobile station apparatus having one transmission antenna. That is, from the base station apparatus side, it is assumed that the mobile station apparatus logically transmits a signal (information) using one transmission antenna.

  For example, the base station apparatus sets a single antenna port mode (also referred to as a single antenna port scheme) to the mobile station apparatus using UE-specifically (UE-specifically) using RRC signaling. ) Can be set. That is, the base station apparatus can set using RRC signaling to transmit PDSCH through a single antenna port. Moreover, the base station apparatus can set that a mobile station apparatus transmits PUSCH by a single antenna port using RRC signaling.

  In addition, for example, the base station apparatus uses a multi-antenna port mode (also referred to as a multi-antenna port scheme) for the mobile station apparatus by using RRC signaling. -specifically). That is, the base station apparatus can set to transmit PDSCH through the multi-antenna port using RRC signaling. Moreover, the base station apparatus can set that a mobile station apparatus transmits PUSCH by a multi-antenna port using RRC signaling.

  For example, the base station apparatus may notify the mobile station apparatus that the PDSCH is transmitted through the multi-antenna port by setting the PDSCH transmission mode (which may be a transmission scheme) using RRC signaling. it can. Further, for example, the base station apparatus notifies the mobile station apparatus that the PUSCH is transmitted through the multi-antenna port by setting the PUSCH transmission mode (which may be a transmission scheme) using RRC signaling. be able to.

  Here, the base station apparatus can set the setting of the single antenna port mode or the multi-antenna port mode for PDSCH (also referred to as the setting of the number of antenna ports) for the mobile station apparatus independently of the transmission of the SRS. it can. Further, the base station apparatus can set the single antenna port mode or the multi-antenna port mode for PUSCH (also referred to as the setting of the number of antenna ports) for the mobile station apparatus independently of the SRS transmission. .

  Here, since PDCCH addressed to a plurality of mobile station devices (PDCCH for a plurality of mobile station devices, PDCCH used for group scheduling) needs to be received (detected) by a plurality of mobile station devices, By the base station apparatus, all mobile station apparatuses are arranged in a common search area (also referred to as CSS: Common Search Space) in which PDCCH search (detection) is attempted.

  Also, the DCI format used when the base station apparatus transmits PDSCH through a single antenna port is also arranged in the common search area (CSS) by the base station apparatus. Further, the DCI format used when the mobile station apparatus transmits PUSCH through a single antenna port is also arranged in the common search area (CSS) by the base station apparatus. For example, DCI format 1 / 1A and DCI format 0 are arranged in the common search area (CSS) by the base station apparatus. That is, DCI format A, which will be described later, is arranged in the common search area (CSS) by the base station apparatus. Here, the DCI format 1 / 1A and the DCI format 0 are also arranged in the mobile station device specific search area (USS) by the base station device.

  Also, a PDCCH addressed to a certain (specific) mobile station device is a mobile station device specific search area (USS: User equipment specific Search) where a certain (specific) mobile station device tries to search (detect) the PDCCH by the base station device Space, also called UE specific Search Space).

  For example, DCI format 1 / 1A, DCI format 2, DCI format 0, and DCI format 0A are arranged in the mobile station device specific search area (USS) by the base station device. That is, the DCI format used when the base station apparatus transmits PDSCH by multiport is arranged only in the mobile station apparatus specific search area (USS) by the base station apparatus. Furthermore, the DCI format used when the mobile station apparatus transmits the PUSCH by multiport is arranged only in the mobile station apparatus specific search area (USS) by the base station apparatus. That is, DCI format B described later is arranged only in the mobile station device specific search area (USS) by the base station device.

  The DCI format can define a plurality of DCI formats having the same number of bits and a plurality of DCI formats having different numbers of bits. For example, a flag for identifying each DCI format is assigned to a plurality of DCI formats having the same number of bits, and the mobile station apparatus identifies each DCI format by checking the given flag. can do. Further, for example, the mobile station apparatus can identify each DCI format by trying different decoding processes for each of a plurality of DCI formats having different numbers of bits.

  The base station apparatus assigns a sequence obtained by scrambling a cyclic redundancy check (CRC) code generated based on DCI with RNTI (Radio Network Temporary Identity) to DCI, and transmits the DCI to the mobile station apparatus To do. The mobile station apparatus changes the interpretation of DCI according to which RNTI the cyclic redundancy check code is scrambled. For example, when the cyclic redundancy check code is scrambled by the C-RNTI (Cell-Radio Network Temporary Identity) assigned by the base station apparatus, the mobile station apparatus transmits the DCI to the own apparatus. Judged to be 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 cyclic redundancy check code, and the mobile station apparatus checks the cyclic redundancy check code for each set of CCEs in which the PDCCH may be configured. The PDCCH addressed to its own device is acquired.

  This process by the mobile station apparatus is also referred to as blind decoding, and the range of CCE sets in which the mobile station apparatus may constitute a PDCCH for performing blind decoding is the search space (Search Space). ). That is, the mobile station apparatus performs blind decoding on the CCE in the search area and detects the PDCCH addressed to itself.

  When the PDCCH addressed to the mobile station apparatus includes PDSCH resource allocation, the mobile station apparatus uses the PDSCH according to the resource allocation instructed by the PDCCH from the base station apparatus, and uses the downlink signal (downlink data). (Transport block for downlink shared channel (DL-SCH)) and / or downlink control data (downlink control information) and / or downlink reference signal (DRS)) are received. That is, this PDCCH can also be said to be a signal for performing resource allocation for the downlink (hereinafter also referred to as “downlink transmission permission signal” or “downlink grant”).

  In addition, when the PDCCH addressed to the mobile station apparatus includes PUSCH resource allocation, the mobile station apparatus uses the PUSCH according to the resource allocation instructed by the PDCCH from the base station apparatus, and transmits an uplink signal (uplink). Link data (transport block for uplink shared channel (UL-SCH)) and / or uplink control data (uplink control information) and / or uplink reference signal (URS) are transmitted. That is, this PDCCH can be said to be a signal that permits data transmission on the uplink (hereinafter also referred to as “uplink transmission permission signal” or “uplink grant”).

  The PDSCH is a channel used for transmitting downlink data (transport block for the downlink shared channel (DL-SCH)) or paging information (paging channel: PCH). The base station apparatus transmits a downlink transport block (transport block for the downlink shared channel (DL-SCH)) to the mobile station apparatus using the PDSCH assigned by the PDCCH.

  Here, the downlink data indicates, for example, user data, and DL-SCH is a transport channel. In DL-SCH, HARQ and dynamic adaptive radio link control are supported, and beamforming can be used. The DL-SCH supports dynamic resource allocation and semi-static resource allocation.

  PUSCH is a channel mainly used for transmitting uplink data (transport block for uplink shared channel (UL-SCH)). The mobile station apparatus transmits the uplink transport block (transport block for the uplink shared channel (UL-SCH)) to the base station apparatus using the PUSCH allocated by the PDCCH transmitted from the base station apparatus. . When the base station apparatus schedules the mobile station apparatus, uplink control information (UCI) is also transmitted using PUSCH.

  Here, the uplink data indicates, for example, user data, and UL-SCH is a transport channel. The PUSCH is a physical channel defined (configured) by the time domain and the frequency domain. 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.

  Here, in the uplink data (UL-SCH) and the downlink data (DL-SCH), a radio resource control signal (hereinafter referred to as “RRC signaling: Radio Resource Control”) exchanged between the base station apparatus and the mobile station apparatus. (Referred to as “Signaling”). Further, the uplink data (UL-SCH) and the downlink data (DL-SCH) may include a MAC (Medium Access Control) control element exchanged between the base station apparatus and the mobile station apparatus. .

  The base station apparatus and the mobile station apparatus transmit and receive RRC signaling in an upper layer (Radio Resource Control layer). Further, the base station apparatus and the mobile station apparatus transmit and receive the MAC control element in an upper layer (medium access control (MAC) layer).

  PUCCH is a channel used for transmitting uplink control information (UCI). Here, the uplink control information includes channel state information (CSI), channel quality identifier (CQI), precoding matrix identifier (PMI), and rank identifier (RI). Further, the uplink control information includes information indicating ACK / NACK in HARQ for the downlink transport block. Further, the uplink control information includes a scheduling request for requesting allocation of resources for the mobile station apparatus to transmit uplink data (requesting transmission on UL-SCH).

[Configuration of base station apparatus]
FIG. 2 is a block diagram showing a schematic configuration of the base station apparatus 100 according to the embodiment of the present invention. The base station apparatus 100 includes a data control unit 101, a transmission data modulation unit 102, a radio unit 103, a scheduling unit 104, a channel estimation unit 105, a received data demodulation unit 106, a data extraction unit 107, and an upper layer. 108 and an antenna 109. The radio unit 103, the scheduling unit 104, the channel estimation unit 105, the reception data demodulation unit 106, the data extraction unit 107, the upper layer 108 and the antenna 109 constitute a reception unit, and the data control unit 101, the transmission data modulation unit 102, The radio unit 103, the scheduling unit 104, the upper layer 108, and the antenna 109 constitute a transmission unit.

  The antenna 109, the radio unit 103, the channel estimation unit 105, the reception data demodulation unit 106, and the data extraction unit 107 perform processing on the uplink physical layer. The antenna 109, the radio unit 103, the transmission data modulation unit 102, and the data control unit 101 perform downlink physical layer processing.

  The data control unit 101 receives a transport channel from the scheduling unit 104. The data control unit 101 maps the transport channel and the signal and channel generated in the physical layer to the physical channel based on the scheduling information input from the scheduling unit 104. Each piece of data mapped as described above is output to transmission data modulation section 102.

  The transmission data modulation unit 102 modulates transmission data to the OFDM scheme. The transmission data modulation unit 102 performs data modulation, coding, and coding on the data input from the data control unit 101 based on the scheduling information from the scheduling unit 104 and the modulation scheme and coding scheme corresponding to each PRB. Signal processing such as serial / parallel conversion of input signals, IFFT (Inverse Fast Fourier Transform) processing, CP (Cyclic Prefix) insertion, and filtering is performed to generate transmission data, and to wireless section 103 Output. Here, the scheduling information includes downlink physical resource block PRB (Physical Resource Block) allocation information, for example, physical resource block position information composed of frequency and time, and the modulation scheme and coding corresponding to each PRB. The scheme includes, for example, information such as a modulation scheme: 16QAM and a coding rate: 2/3 coding rate.

  Radio section 103 up-converts the modulation data input from transmission data modulation section 102 to a radio frequency to generate a radio signal, and transmits the radio signal to mobile station apparatus 200 via antenna 109. Radio section 103 receives an uplink radio signal from mobile station apparatus 200 via antenna 109, down-converts it into a baseband signal, and receives received data as channel estimation section 105 and received data demodulation section 106. And output.

  The scheduling unit 104 performs processing of a medium access control (MAC) layer. The scheduling unit 104 performs mapping between logical channels and transport channels, downlink and uplink scheduling (HARQ processing, selection of transport format, etc.), and the like. Since the scheduling unit 104 controls the processing units of each physical layer in an integrated manner, the scheduling unit 104, the antenna 109, the radio unit 103, the channel estimation unit 105, the reception data demodulation unit 106, the data control unit 101, the transmission data modulation There is an interface between the unit 102 and the data extraction unit 107 (not shown).

  In downlink scheduling, the scheduling unit 104 uses uplink signals (CSI, CQI, PMI, RI, information indicating ACK / NACK for downlink transport blocks, scheduling requests, references, and the like received from the mobile station apparatus 200. Signal), the PRB information that can be used by each mobile station apparatus, the buffer status, the scheduling information input from the higher layer 108, and the like. Selection processing of transmission form, that is, allocation of physical resource blocks, modulation scheme and coding scheme, etc.), retransmission control in HARQ, and generation of scheduling information used for downlink. The scheduling information used for downlink scheduling is output to the data control unit 101.

  Further, in uplink scheduling, the scheduling unit 104 estimates the uplink channel state (radio channel state) output from the channel estimation unit 105, the resource allocation request from the mobile station device 200, and each mobile station device 200. Based on the available PRB information, scheduling information input from the higher layer 108, etc., an uplink transport format for modulating each data (transmission form, ie, physical resource block allocation and modulation scheme and Encoding information and the like, and scheduling information used for uplink scheduling. Scheduling information used for uplink scheduling is output to the data control unit 101.

  In addition, the scheduling unit 104 maps the downlink logical channel input from the higher layer 108 to the transport channel, and outputs it to the data control unit 101. In addition, the scheduling unit 104 processes the control data and the transport channel acquired in the uplink input from the data extraction unit 107 as necessary, maps them to the uplink logical channel, and outputs them to the upper layer 108. To do.

  Channel estimation section 105 estimates an uplink channel state from a demodulation reference signal (DRS) for demodulation of uplink data, and outputs the estimation result to reception data demodulation section 106. Further, in order to perform uplink scheduling, an uplink channel state is estimated from a sounding reference signal (SRS), and the estimation result is output to the scheduling section 104.

  Received data demodulator 106 also serves as an OFDM demodulator and / or DFT-Spread-OFDM (DFT-S-OFDM) demodulator that demodulates received data modulated in the OFDM scheme and / or SC-FDMA scheme. Yes. Based on the uplink channel state estimation result input from the channel estimation unit 105, the reception data demodulation unit 106 performs DFT conversion, subcarrier mapping, IFFT conversion, filtering, and the like on the modulation data input from the radio unit 103. Are subjected to demodulation processing and output to the data extraction unit 107.

  The data extraction unit 107 confirms whether the data input from the reception data demodulation unit 106 is correct and outputs a confirmation result (ACK or NACK) to the scheduling unit 104. The data extraction unit 107 separates the data input from the reception data demodulation unit 106 into a transport channel and physical layer control data, and outputs the data to the scheduling unit 104. The separated control data includes CSI, CQI, PMI, RI transmitted from the mobile station apparatus 200, information indicating ACK / NACK for the downlink transport block, a scheduling request, and the like.

  The upper layer 108 performs processing of a packet data convergence protocol (PDCP) layer, a radio link control (RLC) layer, and a radio resource control (RRC) layer. The upper layer 108 integrates and controls the processing units of the lower layer, so the upper layer 108, the scheduling unit 104, the antenna 109, the radio unit 103, the channel estimation unit 105, the received data demodulation unit 106, the data control unit 101, There is an interface between the transmission data modulation unit 102 and the data extraction unit 107 (not shown).

  The upper layer 108 includes a radio resource control unit 110 (also referred to as a control unit). Further, the radio resource control unit 110 manages various setting information, system information, paging control, communication state management of each mobile station device, mobility management such as handover, management of buffer status for each mobile station device, Management of unicast and multicast bearer connection settings, management of mobile station identifiers (UEID), and the like are performed. The upper layer 108 exchanges information with another base station apparatus and information with an upper node.

[Configuration of mobile station device]
FIG. 3 is a block diagram showing a schematic configuration of the mobile station apparatus 200 according to the embodiment of the present invention. The mobile station apparatus 200 includes a data control unit 201, a transmission data modulation unit 202, a radio unit 203, a scheduling unit 204, a channel estimation unit 205, a reception data demodulation unit 206, a data extraction unit 207, and an upper layer. 208 and an antenna 209. The data control unit 201, transmission data modulation unit 202, radio unit 203, scheduling unit 204, higher layer 208, and antenna 209 constitute a transmission unit, and the radio unit 203, scheduling unit 204, channel estimation unit 205, received data demodulation unit Unit 206, data extraction unit 207, upper layer 208, and antenna 209 constitute a reception unit.

  The data control unit 201, the transmission data modulation unit 202, and the radio unit 203 perform processing on the uplink physical layer. The radio unit 203, the channel estimation unit 205, the received data demodulation unit 206, and the data extraction unit 207 perform downlink physical layer processing.

  The data control unit 201 receives a transport channel from the scheduling unit 204. The transport channel and the signal and channel generated in the physical layer are mapped to the physical channel based on the scheduling information input from the scheduling unit 204. Each piece of data mapped in this way is output to transmission data modulation section 202.

  The transmission data modulation unit 202 modulates transmission data into the OFDM scheme and / or the SC-FDMA scheme. The transmission data modulation unit 202 performs data modulation, DFT (Discrete Fourier Transform) processing, subcarrier mapping, IFFT (Inverse Fast Fourier Transform) processing, CP insertion, filtering, and other signals on the data input from the data control unit 201. Processing is performed, transmission data is generated, and output to the wireless unit 203.

  Radio section 203 up-converts the modulation data input from transmission data modulation section 202 to a radio frequency, generates a radio signal, and transmits the radio signal to base station apparatus 100 via antenna 209. Radio section 203 receives a radio signal modulated with downlink data from base station apparatus 100 via antenna 209, down-converts it to a baseband signal, and receives the received data as channel estimation section 205. And output to the received data demodulation section 206.

  The scheduling unit 204 performs processing of a medium access control (MAC) layer. The scheduling unit 204 performs mapping between logical channels and transport channels, downlink and uplink scheduling (HARQ processing, transport format selection, etc.), and the like. Since the scheduling unit 204 controls the processing units of each physical layer in an integrated manner, the scheduling unit 204, the antenna 209, the data control unit 201, the transmission data modulation unit 202, the channel estimation unit 205, the reception data demodulation unit 206, the data There is an interface between the extraction unit 207 and the wireless unit 203 (not shown).

  In downlink scheduling, the scheduling unit 204 controls reception of transport channels, physical signals, and physical channels based on scheduling information (transport format and HARQ retransmission information) from the base station apparatus 100 and the upper layer 208, and the like. Scheduling information used for HARQ retransmission control and downlink scheduling is generated. The scheduling information used for downlink scheduling is output to the data control unit 201.

  In uplink scheduling, the scheduling unit 204 receives the uplink buffer status input from the higher layer 208 and uplink scheduling information from the base station apparatus 100 input from the data extraction unit 207 (transport format and HARQ retransmission). Information), and scheduling processing for mapping the uplink logical channel input from the upper layer 208 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 100 is used for the uplink transport format. The scheduling information is output to the data control unit 201.

  Also, the scheduling unit 204 maps the uplink logical channel input from the higher layer 208 to the transport channel, and outputs it to the data control unit 201. The scheduling unit 204 also outputs to the data control unit 201 the CSI, CQI, PMI, RI, and CRC check confirmation results input from the data extraction unit 207 input from the channel estimation unit 205. . In addition, the scheduling unit 204 processes the control data and the transport channel acquired in the downlink input from the data extraction unit 207 as necessary, maps them to the downlink logical channel, and outputs them to the upper layer 208. To do.

  Channel estimation section 205 estimates the downlink channel state from the demodulated reference signal for downlink data demodulation, and outputs the estimation result to reception data demodulation section 206. The channel estimation unit 205 also notifies the base station apparatus 100 of the downlink channel state (radio channel state, CSI, CQI, PMI, RI) from the downlink reference signal to the downlink channel. The state is estimated, and the estimation result is output to the scheduling unit 204 as, for example, CSI, CQI, PMI, or RI.

  Received data demodulation section 206 demodulates received data modulated by the OFDM method. Reception data demodulation section 206 performs demodulation processing on the modulated data input from radio section 203 based on the downlink channel state estimation result input from channel estimation section 205 and outputs the result to data extraction section 207. To do.

  The data extraction unit 207 performs a CRC check on the data input from the reception data demodulation unit 206, confirms whether the data is correct, and outputs a confirmation result (information indicating ACK or NACK) to the scheduling unit 204. The data extraction unit 207 separates the data input from the reception data demodulation unit 206 into transport channel and physical layer control data, and outputs the data to the scheduling unit 204. The separated control data includes scheduling information such as downlink or uplink resource allocation and uplink HARQ control information.

  The upper layer 208 performs processing of a packet data convergence protocol (PDCP) layer, a radio link control (RLC) layer, and a radio resource control (RRC) layer. The upper layer 208 integrates and controls the processing units of the lower layer, so that the upper layer 208, the scheduling unit 204, the antenna 209, the data control unit 201, the transmission data modulation unit 202, the channel estimation unit 205, the reception data demodulation unit 206, an interface between the data extraction unit 207 and the radio unit 203 exists (not shown).

  The upper layer 208 has a radio resource control unit 210 (also referred to as a control unit). The radio resource control unit 210 manages various setting information, system information, paging control, own station communication status, mobility management such as handover, buffer status management, unicast and multicast bearer connection setting. Management and management of mobile station identifier (UEID).

(First embodiment)
Next, a first embodiment in a mobile communication system using the base station apparatus 100 and the mobile station apparatus 200 will be described. In the first embodiment, the base station apparatus notifies the mobile station apparatus of a DCI format including information instructing single antenna port transmission or multi-antenna port transmission for SRS. Or SRS with respect to a multi-antenna is transmitted to a base station apparatus.

  The base station apparatus notifies the mobile station apparatus of a DCI format including information instructing single antenna port transmission for SRS, and the mobile station apparatus transmits SRS for the single antenna port to the base station apparatus according to the information. .

  Further, the base station apparatus notifies the mobile station apparatus of a DCI format including information instructing multi-antenna transmission for SRS, and the mobile station apparatus transmits SRS for the multi-antenna to the base station apparatus according to the information.

  At this time, the base station apparatus instructs (requests, triggers) SRS transmission to the mobile station apparatus using the DCI format, and the mobile station apparatus aperiodically follows the DCI format from the base station apparatus. SRS (A-SRS) is transmitted to the base station apparatus. For example, the base station apparatus can instruct the mobile station apparatus to transmit SRS by notifying the mobile station apparatus including an SRS transmission instruction in the DCI format. Also, for example, when the SRS transmission instruction is included in the DCI format from the base station apparatus, the mobile station apparatus can transmit SRS (A-SRS) to the base station apparatus aperiodically. . Hereinafter, aperiodic SRS (A-SRS) transmission is also simply referred to as SRS transmission.

  FIG. 4 is a diagram illustrating an example of SRS transmission in the first embodiment. Here, the first embodiment can also be applied to the above-described mobile communication system that has been subjected to frequency aggregation (symmetric frequency band aggregation, asymmetric frequency band aggregation). In FIG. 4, the horizontal axis indicates a subframe (time). In FIG. 4, as an example, subframes from subframe n−2 to subframe n + 20 are illustrated.

  FIG. 4 is applicable to the operation when the base station apparatus is set to transmit a physical channel (for example, PDSCH) to the mobile station apparatus through a multi-antenna port. In FIG. 4, for example, the base station apparatus moves a physical channel (for example, PDSCH) through a multi-antenna port by setting a transmission mode (transmission scheme) of the physical channel (for example, PDSCH) using RRC signaling. Notification of transmission to the station apparatus can be made.

  FIG. 4 is also applicable to an operation when the base station apparatus is set to transmit a physical channel (for example, PUSCH) to the base station apparatus through a multi-antenna port. In FIG. 4, for example, the base station apparatus sets the transmission mode (transmission scheme) of the physical channel (for example, PUSCH) using RRC signaling, thereby allowing the physical channel (for example, PUSCH) to be Notification of transmission to the station apparatus can be made.

  In FIG. 4, the base station apparatus performs subframe n−2, subframe n, subframe n + 2, subframe n + 4, subframe n + 6, subframe n + 8, subframe n + 10, subframe n + 12 as SRS subframes. This shows that subframe n + 14, subframe n + 16, subframe n + 18, and subframe n + 20 are set in the mobile station apparatus. The SRS subframe will be described later.

  In FIG. 4, the base station apparatus instructs (requests, triggers) the transmission of SRS to the mobile station apparatus using the DCI format, and the mobile station apparatus aperiodically follows the DCI format from the base station apparatus. Thus, SRS (A-SRS) is transmitted to the base station apparatus.

  For example, in FIG. 4, the base station apparatus can instruct the mobile station apparatus to transmit SRS using the DCI format that is used only for transmitting PDSCH through a single antenna port. For example, the base station apparatus transmits the SRS to the mobile station apparatus by notifying the mobile station apparatus including the SRS transmission instruction in the DCI format used only for transmitting the PDSCH through the single antenna port. Can be instructed.

  That is, the base station apparatus instructs the mobile station apparatus to transmit SRS using the DCI format 1 / 1A (which may be the same DCI format as the DCI format 1 / 1A) as described above. Can do.

  Further, for example, the base station apparatus can instruct the mobile station apparatus to transmit SRS using the DCI format that is used only for the mobile station apparatus to transmit PUSCH through a single antenna port. For example, the base station apparatus notifies the mobile station apparatus of the DCI format used only for the mobile station apparatus to transmit the PUSCH through the single antenna port, including the SRS transmission instruction, to the mobile station apparatus. , SRS transmission can be instructed.

  That is, the base station apparatus can instruct the mobile station apparatus to transmit SRS using DCI format 0 (which may be the same DCI format as DCI format 0) as described above.

  Hereinafter, for the sake of simplicity, the DCI format (DCI format 1 / 1A, the same as DCI format 1 / 1A used only for transmitting the downlink / uplink physical channel (PDSCH / PUSCH) via a single antenna port) DCI format, DCI format 0, and DCI format similar to DCI format 0) are referred to as DCI format A.

  That is, DCI format A is used only for the base station apparatus to transmit PDSCH through a single antenna port (hereinafter, this DCI format A is also referred to as DCI format A for downlink). The DCI format A is used only for the mobile station apparatus to transmit the PUSCH through a single antenna port (hereinafter, this DCI format A is also referred to as DCI format A for uplink). Here, the DCI format A for the downlink is used by the base station apparatus to schedule one PDSCH codeword. Also, the DCI format A for uplink is used by the base station apparatus to schedule one PUSCH codeword.

  For example, the downlink control information transmitted in the DCI format A for downlink includes resource allocation header information (Resource allocation header) indicating a resource allocation type, resource allocation information (Resource block assignment) for PDSCH, modulation scheme and encoding MCS information (Modulation and Coding Scheme) indicating rate, information indicating HARQ process number (HARQ process number), information for identifying whether transmission data is new data (New data indicator), and parameters for retransmission Information (Redundancy version) and TPC command information (TPC command for PUCCH) for PUCCH are included.

  Also, for example, downlink control information transmitted in the DCI format A for the downlink includes information used for identification with other DCI formats (Flag for format differentiation), and identification of a virtual resource block allocation method. Information (Localized / Distributed VRB assignment flag) and padding bit (Padding bit) are included.

  That is, an information field to which these downlink control information (downlink control information bits) is mapped is defined in DCI format A for the downlink.

  Further, for example, in downlink control information transmitted in DCI format A for uplink, information used for discrimination from other DCI formats (Flag for format differentiation), information instructing transmission with hopping (Hopping flag), resource allocation information for PUSCH (Resource block assignment), modulation scheme and coding rate, information indicating parameters for retransmission (Modulation and Coding Scheme and Redundancy version), and whether transmission data is new data Information (New data indicator), TPC command for scheduled PUSCH (TPC command for scheduled PUSCH) information, information indicating cyclic shift applied to demodulation reference signal (Cyclic shift for DM RS), CQI transmission request information ( CQI request) and padding bit.

  That is, an information field to which these downlink control information (downlink control information bits) is mapped is defined in the DCI format A for the uplink.

  The base station apparatus transmits DCI format A (DCI format A for downlink, DCI format A for uplink) including an SRS transmission instruction to the mobile station apparatus, and instructs the mobile station apparatus to transmit SRS. can do.

  Here, the SRS transmission instruction by the base station apparatus can be realized, for example, by defining an information field (for example, a 1-bit information field) for the SRS transmission instruction in DCI format A.

  Further, the SRS transmission instruction is set by setting a specific information field (information) in the information field (information) included in the DCI format A for the downlink as described above to a specific value. Can be realized.

  For example, an SRS transmission instruction can be realized by setting Flag for format differentiation included in DCI format A for downlink to “0” and Localized / Distributed VRB assignment flag to “1”. At this time, the remaining information fields (information fields other than a specific information field) included in the DCI format A for the downlink are stored in an information field (mobile station device for transmitting SRS) by the mobile station device. It can also be used as an information field to which A-SRS parameters used when transmitting SRS are mapped.

  Further, for example, the SRS transmission instruction sets a specific information field (information) in the information field (information) included in the DCI format A for the uplink as described above to a specific value. Can be realized.

  For example, an SRS transmission instruction can be realized by setting Flag for format differentiation included in DCI format A for uplink to “0” and Resource block assignment to “1”. At this time, the remaining information field (information field other than a specific information field) included in the DCI format A for the uplink is used as an information field for transmitting the SRS (when the mobile station apparatus transmits the SRS). It can also be used as an information field to which A-SRS parameters used for the

  Here, the specification of which information field (which information) included in DCI format A (DCI format A for downlink and DCI format A for uplink) is set to which value indicates an SRS transmission instruction is a specification. Etc., and can be known between the base station apparatus and the mobile station apparatus.

  Depending on whether or not the predefined information field is set to a certain value, the mobile station apparatus instructs scheduling for downlink / uplink, or instructs transmission of SRS, for example. Recognize that That is, the mobile station apparatus changes the interpretation of the information field included in the DCI format A depending on whether or not the predefined information field is set to a specific value.

  That is, in FIG. 4, the base station apparatus explicitly includes an SRS transmission instruction in DCI format A and notifies the mobile station apparatus (for example, moves 1-bit information instructing SRS transmission). The mobile station device can be instructed to transmit SRS. Further, the base station apparatus implicitly notifies the mobile station apparatus of an SRS transmission instruction by setting a specific information field included in the DCI format A to a specific value, and the mobile station apparatus Can be instructed to transmit SRS.

  In FIG. 4, the base station apparatus can instruct the mobile station apparatus to transmit SRS using the DCI format used for transmitting the PDSCH through the multi-antenna port. For example, the base station apparatus notifies the mobile station apparatus of SRS transmission by notifying the mobile station apparatus including the SRS transmission instruction in the DCI format used for transmitting the PDSCH through the multi-antenna port. Can be directed.

 That is, the base station apparatus can instruct the mobile station apparatus to transmit SRS using DCI format 2 (which may be the same DCI format as DCI format 2) as described above.

  For example, the base station apparatus can instruct the mobile station apparatus to transmit SRS using the DCI format used for the mobile station apparatus to transmit the PUSCH through the multi-antenna port. For example, the base station apparatus notifies the mobile station apparatus of the DCI format used for transmitting the PUSCH through the multi-antenna port, including the SRS transmission instruction, to the mobile station apparatus. , SRS transmission can be instructed.

 That is, the base station apparatus can instruct the mobile station apparatus to transmit SRS using DCI format 0A as described above (or a DCI format similar to DCI format 0A).

  Hereinafter, for simplicity, a DCI format (DCI format similar to DCI format 2, DCI format 2, DCI format used for transmitting the downlink / uplink physical channel (PDSCH / PUSCH) through a multi-antenna port) 0A, DCI format similar to DCI format 0A) is called DCI format B.

  That is, the DCI format B is used for the base station apparatus to transmit the PDSCH through the multi-antenna port (hereinafter, this DCI format B is also referred to as DCI format B for the downlink). Also, the DCI format B is used by the mobile station device to transmit the PUSCH through the multi-antenna port (hereinafter, this DCI format B is also referred to as the DCI format B for the uplink). Here, the DCI format B for the downlink is used by the base station apparatus to schedule two (plurality) PDSCH codewords. Also, DCI format B for uplink is used by the base station apparatus to schedule two (plural) PUSCH codewords.

  Here, the DCI format B for the downlink may be used for the base station apparatus to transmit PDSCH through a single antenna port. Also, the DCI format B for uplink may be used for the mobile station apparatus to transmit PUSCH through a single antenna port.

  For example, the downlink control information transmitted in the DCI format B for downlink includes resource allocation header information (Resource allocation header) indicating a resource allocation type, resource allocation information (Resource block assignment) for PDSCH, ) MCS information (Modulation and Coding Scheme) indicating the modulation scheme and coding rate for each codeword (also referred to as a transport block), information indicating the HARQ process number (HARQ process number), and two (multiple) codewords Information for identifying whether transmission data is new data (New data indicator) for each, information (Redundancy version) for indicating parameters for retransmission for each of the two (multiple) codewords (two (multiple) ) Applied to the layer to which the codeword is mapped Preprocessing information (precoding information, precoding information), it included TPC command information (TPC COMMAND for PUCCH) is for PUCCH.

 That is, an information field to which these downlink control information (downlink control information bits) is mapped is defined in DCI format B for the downlink.

  Further, for example, in downlink control information transmitted in DCI format B for uplink, information used for discrimination from other DCI formats (Flag for format differentiation), information instructing transmission with hopping (Hopping flag), resource allocation information for PUSCH (Resource block assignment), information indicating the modulation scheme and coding rate for each of two (plural) codewords (also referred to as transport blocks), and parameters for retransmission (Modulation and Coding Scheme) and Redundancy version) Information for identifying whether transmission data is new data for each of the two (multiple) codewords (New data indicator), TPC command for scheduled PUSCH (TPC command for scheduled PUSCH) Information, two (multiple) codewords mapped Information indicating the cyclic shift applied to the demodulation reference signal transmitted for each layer (Cyclic shift for DM RS), pre-processing information applied to the layer to which two (multiple) codewords are mapped Recording information, precoding information), CQI transmission request information (CQI request), and padding bits are included.

  That is, an information field to which the downlink control information (downlink control information bits) is mapped is defined in the DCI format B for the uplink.

  The base station apparatus transmits DCS format B (DCI format B for downlink, DCI format B for uplink) including an SRS transmission instruction to the mobile station apparatus, and instructs the mobile station apparatus to transmit SRS. can do.

  Here, the SRS transmission instruction by the base station apparatus can be realized by defining an information field (for example, a 1-bit information field) for the SRS transmission instruction in DCI format B, for example.

  Further, the SRS transmission instruction is set by setting a specific information field (information) in the information field (information) included in the DCI format B for the downlink as described above to a specific value. Can be realized.

  For example, an SRS transmission instruction can be realized by setting Flag for format differentiation included in DCI format B for downlink to “0” and Localized / Distributed VRB assignment flag to “1”. Also, at this time, the remaining information fields (information fields other than a specific information field) included in the DCI format B for the downlink are information fields for the mobile station device to transmit SRS (the mobile station device It can also be used as an information field to which A-SRS parameters used when transmitting SRS are mapped.

  In addition, for example, the SRS transmission instruction sets a specific information field (information) in the information field (information) included in the DCI format B for the uplink as described above to a specific value. Can be realized.

  For example, an SRS transmission instruction can be realized by setting Flag for format differentiation included in DCI format B for uplink to “0” and Resource block assignment to “1”. At this time, the remaining information fields (information fields other than a specific information field) included in the DCI format B for the uplink are used as information fields for transmitting the SRS (when the mobile station apparatus transmits the SRS). It can also be used as an information field to which A-SRS parameters used for the above are mapped.

  Here, the specification of which information field (which information) included in DCI format B (DCI format B for downlink, DCI format B for uplink) is set to which value indicates an SRS transmission instruction. Etc., and can be known between the base station apparatus and the mobile station apparatus.

  Depending on whether or not the predefined information field is set to a certain value, the mobile station apparatus instructs scheduling for downlink / uplink, or instructs transmission of SRS, for example. Recognize that That is, the mobile station apparatus changes the interpretation of the information field included in the DCI format B depending on whether or not the predefined information field is set to a specific value.

  That is, in FIG. 4, the base station apparatus explicitly includes an SRS transmission instruction in DCI format B and notifies the mobile station apparatus (for example, moves 1-bit information instructing SRS transmission). The mobile station device can be instructed to transmit SRS. Further, the base station apparatus implicitly notifies the mobile station apparatus of an SRS transmission instruction by setting a specific information field included in DCI format B to a specific value, and the mobile station apparatus Can be instructed to transmit SRS.

  The mobile station apparatus instructed to transmit A-SRS by the base station apparatus transmits SRS (A-SRS) to the base station apparatus aperiodically. For example, the mobile station apparatus transmits the SRS in a predetermined subframe (for example, a subframe after 4 subframes) from the subframe that has received the DCI format including the SRS transmission instruction from the base station apparatus.

  Further, for example, the mobile station apparatus may transmit the SRS in an SRS subframe (subframe in which SRS can be transmitted) after the subframe that has received the DCI format including the SRS transmission instruction from the base station apparatus. it can. For example, the mobile station apparatus has an SRS subframe closest to a subframe after a predetermined period from a subframe that has received a DCI format including an SRS transmission instruction from the base station apparatus (for example, four subframes from the subframe that has received the DCI format) The SRS can be transmitted in the (first) SRS subframe that is closest to the later subframe.

  FIG. 4 shows that the mobile station apparatus transmits the SRS in the (first) SRS subframe closest to the subframe four subframes after the subframe that received the DCI format including the SRS transmission instruction from the base station apparatus. It shows that.

  Here, the base station apparatus can set a cell-specifically SRS subframe (subframe in which SRS can be transmitted) to the mobile station apparatus. Moreover, the base station apparatus can set a SRS sub-frame with respect to a mobile station apparatus in UE-specifically. For example, the base station apparatus can set the SRS subframe to the mobile station apparatus in a cell-specific manner using broadcast information. Moreover, the base station apparatus can set an SRS subframe to a mobile station apparatus peculiar to a mobile station apparatus using RRC signaling.

  Moreover, the base station apparatus can set the parameter (A-SRS parameter) used when a mobile station apparatus transmits SRS (A-SRS) aperiodically with respect to a mobile station apparatus. For example, the base station apparatus can set the A-SRS parameter to the mobile station apparatus in a manner specific to the mobile station apparatus using RRC signaling. Further, as described above, the base station apparatus can notify the mobile station apparatus by including the A-SRS parameter in the DCI format.

  Here, the A-SRS parameter includes information instructing the transmission bandwidth (SRS transmission bandwidth) when the mobile station apparatus transmits the SRS. The A-SRS parameter includes a cyclic shift (CS: Cyclic Shit) used by the mobile station apparatus to maintain orthogonality between the mobile station apparatuses or between signals (SRS) when transmitting the SRS. The information that indicates is included. Further, the A-SRS parameter includes information indicating a frequency position (frequency allocation position) where the SRS is arranged when the mobile station apparatus transmits the SRS. Further, the A-SRS parameter includes a TPC command (transmission power control information) when the mobile station apparatus transmits the SRS.

  Here, the A-SRS parameter may be set independently for each of a plurality of antenna ports (may be each of a plurality of antennas) by the base station apparatus. For example, the base station apparatus can independently set the A-SRS parameter used when the mobile station apparatus transmits the SRS for the multi-antenna port for each antenna port (may be for each antenna). it can. Moreover, the base station apparatus can set independently the A-SRS parameter used when a mobile station apparatus transmits SRS with respect to a single antenna port.

  For example, the base station apparatus uses an A-SRS parameter for antenna port # 1, an A-SRS parameter for antenna port # 2, and an antenna as A-SRS parameters when the mobile station apparatus transmits SRS for four antenna ports. An A-SRS parameter for port # 3, an A-SRS parameter for antenna port # 4, and an A-SRS parameter for transmitting an SRS for a single antenna port can be set independently.

  A mobile station apparatus transmits SRS to a base station apparatus according to the A-SRS parameter set independently by the base station apparatus. For example, when transmitting the SRS for the multi-antenna port to the base station apparatus, the mobile station apparatus transmits the SRS for each antenna port according to the A-SRS parameter set independently for each of the plurality of antenna ports. Moreover, when transmitting SRS with respect to a single antenna port, a mobile station apparatus transmits SRS with respect to a single antenna port according to the A-SRS parameter set independently.

  Here, when transmitting SRS for a single antenna port, the mobile station apparatus may use any A-SRS parameter set independently for each of the plurality of antenna ports. For example, when the mobile station apparatus transmits an SRS for a single antenna port, the A-SRS parameter for antenna port # 1, the A-SRS parameter for antenna port # 2, the A-SRS parameter for antenna port # 3, and the antenna port Any A-SRS parameter of the A-SRS parameters for # 4 can be used.

  When the mobile station apparatus transmits an SRS for a single antenna port, the base station apparatus uses an ARSRS parameter that is independently set for each of the plurality of antenna ports, so that the base station apparatus performs SRS on the single antenna port. It is no longer necessary to set the A-SRS parameter when transmitting (the A-SRS parameter when transmitting an SRS with a single antenna port and any A-SRS parameter set independently for each of the plurality of antenna ports) And A-SRS parameters can be set using radio resources more efficiently.

  In FIG. 4, the base station apparatus notifies the mobile station apparatus of DCI format A including an SRS transmission instruction. Here, the base station apparatus can notify the mobile station apparatus including information instructing single antenna port transmission or multi-antenna port transmission for SRS in DCI format A. That is, the base station apparatus can notify the mobile station apparatus of DCI format A including an SRS transmission instruction and information for instructing single antenna port transmission or multi-antenna port transmission for SRS.

  For example, the base station apparatus can notify 1-bit information to the mobile station apparatus as information instructing single antenna port transmission or multi-antenna port transmission for SRS. Also, for example, as described above, the base station apparatus changes the interpretation of certain information (information field) included in the DCI format A, thereby allowing the mobile station apparatus to perform single antenna port transmission for SRS or Multi-antenna port transmission can be instructed.

  The mobile station apparatus notified of the DCI format A including the SRS transmission instruction and the information indicating the single antenna port transmission or the multi-antenna port transmission for the SRS by the base station apparatus, the SRS for the single antenna port or the multi-antenna port Is transmitted to the base station apparatus. That is, the mobile station apparatus notified of the DCI format A including the SRS transmission instruction and the information for instructing the single antenna port transmission for the SRS by the base station apparatus transmits the SRS for the single antenna port to the base station apparatus. . Further, the mobile station apparatus notified of the DCI format A including the SRS transmission instruction and the information for instructing the multi-antenna port transmission for the SRS by the base station apparatus transmits the SRS for the multi-antenna port to the base station apparatus. .

  Similarly, in FIG. 4, the base station apparatus notifies the mobile station apparatus including an SRS transmission instruction in DCI format B. Here, the base station apparatus can notify the mobile station apparatus of DCI format B including information instructing single antenna port transmission or multi-antenna port transmission for SRS. That is, the base station apparatus can notify the mobile station apparatus of DCI format B including an SRS transmission instruction and information instructing single antenna port transmission or multi-antenna port transmission for SRS.

  For example, the base station apparatus can notify 1-bit information to the mobile station apparatus as information instructing single antenna port transmission or multi-antenna port transmission for SRS. Further, for example, as described above, the base station apparatus changes the interpretation of certain information (information field) included in the DCI format B, thereby allowing the mobile station apparatus to perform single antenna port transmission for SRS or Multi-antenna port transmission can be instructed.

  The mobile station apparatus notified of the DCI format B including the SRS transmission instruction and the information indicating the single antenna port transmission or the multi-antenna port transmission for the SRS by the base station apparatus is the SRS for the single antenna port or the multi-antenna port. Is transmitted to the base station apparatus. That is, the mobile station apparatus notified of the SRS transmission instruction and the DCI format B including information for instructing the single antenna port transmission for the SRS transmits the SRS for the single antenna port to the base station apparatus. . Further, the mobile station apparatus notified of the SRS transmission instruction and the DCI format B including information instructing the multi-antenna port transmission for the SRS transmits the SRS for the multi-antenna port to the base station apparatus. .

  That is, in FIG. 4, the base station apparatus moves the DCI format (DCI format A and / or DCI format B) including the SRS transmission instruction and information instructing single antenna port transmission or multi-antenna port transmission with respect to the SRS. The mobile station apparatus that notifies the station apparatus and receives this DCI format transmits the SRS for the single antenna port or the multi-antenna port to the base station apparatus.

  In FIG. 4, in subframe n−2, the base station apparatus notifies the mobile station apparatus of DCI format A including an SRS transmission instruction and information instructing multi-antenna port transmission for SRS. The mobile station apparatus notified of this DCI format A transmits the SRS for the multi-antenna port to the base station apparatus in subframe n + 2. In FIG. 4, the SRS indicated by the diagonal line (Tx # 1) rising to the right (Tx # 2), the horizontal line (Tx # 3), and the diagonal line (Tx # 4) This indicates that the SRS for the antenna port (for example, transmission antenna port Tx # 1, transmission antenna port Tx # 2, transmission antenna port Tx # 3, transmission antenna port Tx # 4) is transmitted to the base station apparatus. For example, the mobile station apparatus uses cyclic shift for SRS for multi-antenna ports (for example, transmission antenna port Tx # 1, transmission antenna port Tx # 2, transmission antenna port Tx # 3, transmission antenna port Tx # 4). Can be multiplexed and transmitted to the base station apparatus.

  Similarly, in subframe n + 3, the base station apparatus notifies the mobile station apparatus of DCI format B including an SRS transmission instruction and information instructing single antenna port transmission for SRS. The mobile station apparatus notified of this DCI format B transmits the SRS for the single antenna port to the base station apparatus in subframe n + 8. In FIG. 4, SRS indicated by a vertical line (single antenna port) indicates that the mobile station apparatus transmits the SRS for the single antenna port to the base station apparatus.

  Similarly, in subframe n + 9, the base station apparatus notifies the mobile station apparatus of DCI format B including an SRS transmission instruction and information instructing multi-antenna port transmission for SRS. The mobile station apparatus notified of this DCI format B transmits the SRS for the multi-antenna port to the base station apparatus in subframe n + 14.

  Similarly, in subframe n + 14, the base station apparatus notifies the mobile station apparatus of DCI format A including an SRS transmission instruction and information instructing single antenna port transmission for SRS. The mobile station apparatus notified of this DCI format A transmits the SRS for the single antenna port to the base station apparatus in subframe n + 18.

  As described above, the base station apparatus transmits a DCI format (DCI format A and / or DCI format B) including an SRS transmission instruction and information instructing single antenna port transmission or multi-antenna transmission for the SRS. The mobile station apparatus notifies the mobile station apparatus, and the mobile station apparatus transmits SRS for the single antenna port or the multi-antenna port to the base station apparatus, so that the mobile station apparatus performs SRS transmission for the single antenna port and SRS transmission for the multi-antenna port. It can be switched to dynamic.

  When the mobile station apparatus dynamically switches and transmits the SRS for the single antenna port and the SRS for the multi-antenna port, the base station apparatus is adapted to the efficiency adapted to the channel state based on the SRS transmitted from the mobile station apparatus. Scheduling can be performed. That is, when the base station apparatus and the mobile station apparatus transmit and receive physical channels using a single antenna port or a multi-antenna port, the base station apparatus can perform efficient scheduling.

(Second Embodiment)
Next, a second embodiment in a mobile communication system using the base station device 100 and the mobile station device 200 will be described. In the second embodiment, the base station apparatus notifies the mobile station apparatus of downlink control information (DCI) including an SRS transmission instruction, and the mobile station apparatus corresponds to the format of the downlink control information (DCI). Then, the SRS for the single antenna port or the multi-antenna port is transmitted to the base station apparatus.

  Further, the base station apparatus notifies the mobile station apparatus of the DCI format including the SRS transmission instruction, and the mobile station apparatus transmits the SRS for the single antenna port when the DCI format includes the SRS transmission instruction. Transmitting to the base station apparatus, the DCI format is used only for the mobile station apparatus to transmit the PUSCH through a single antenna port. That is, this DCI format is DCI format A.

  In addition, the base station apparatus notifies the mobile station apparatus of a DCI format including an SRS transmission instruction. When the DCI format includes an SRS transmission instruction, the mobile station apparatus performs SRS for the multi-antenna port. Transmitting to the base station apparatus, the DCI format is used for the mobile station apparatus to transmit the PUSCH through the multi-antenna port. That is, this DCI format is DCI format B.

  The base station apparatus notifies the mobile station apparatus of the DCI format including the SRS transmission instruction. When the mobile station apparatus detects the DCI format in the common search area (CSS), the base station apparatus performs SRS for the single antenna port. You may transmit to a base station apparatus. That is, this DCI format arranged in the common search area (CSS) by the base station apparatus is the DCI format A.

  Here, the base station apparatus notifies the mobile station apparatus of a DCI format including an SRS transmission instruction. When the DCI format includes an SRS transmission instruction, the mobile station apparatus performs SRS for a single antenna port. The DCI format may be used for the mobile station apparatus to transmit the PUSCH through the multi-antenna port. That is, this DCI format is DCI format B.

  In addition, the base station apparatus notifies the mobile station apparatus of a DCI format including an SRS transmission instruction. When the DCI format includes an SRS transmission instruction, the mobile station apparatus performs SRS for the multi-antenna port. Transmitting to the base station apparatus, the DCI format may be used only for the mobile station apparatus to transmit the PUSCH through a single antenna port. That is, this DCI format is DCI format A.

  In addition, the base station apparatus notifies the mobile station apparatus of the DCI format including the SRS transmission instruction, and when the mobile station apparatus detects the DCI format in the common search area (CSS), the base station apparatus performs SRS for the multi-antenna port. You may transmit to a base station apparatus. That is, this DCI format arranged in the common search area (CSS) by the base station apparatus is the DCI format A.

  FIG. 5 is a diagram illustrating an example of SRS transmission in the second embodiment. Here, the second embodiment can also be applied to a mobile communication system that is frequency-aggregated (symmetrical frequency band aggregation, asymmetrical frequency band aggregation) as in the first embodiment. In FIG. 5, the horizontal axis indicates a subframe (time). In FIG. 5, as an example, subframes from subframe n−2 to subframe n + 20 are illustrated.

  5 is applicable to the operation when the base station apparatus is set to transmit a physical channel (for example, PDSCH) to the mobile station apparatus using a multi-antenna port, as in FIG. In FIG. 5, for example, the base station apparatus moves the physical channel (for example, PDSCH) through the multi-antenna port by setting the transmission mode (transmission scheme) of the physical channel (for example, PDSCH) using RRC signaling. Notification of transmission to the station apparatus can be made.

  5 is also applicable to the operation when the base station apparatus is set to transmit a physical channel (for example, PUSCH) to the base station apparatus through a multi-antenna port, as in FIG. . In FIG. 5, for example, the base station apparatus sets the transmission mode (transmission scheme) of the physical channel (for example, PUSCH) using RRC signaling, thereby allowing the physical channel (for example, PUSCH) to be Notification of transmission to the station apparatus can be made.

  In FIG. 5, the base station apparatus performs subframe n−2, subframe n, subframe n + 2, subframe n + 4, subframe n + 6, subframe n + 8, subframe n + 10, subframe n + 12 as SRS subframes. This shows that subframe n + 14, subframe n + 16, subframe n + 18, and subframe n + 20 are set in the mobile station apparatus.

  As in the first embodiment, in FIG. 5, the base station apparatus uses the DCI format A that is used only for transmitting the downlink / uplink physical channel through the single antenna port, to the mobile station apparatus. On the other hand, transmission (request, trigger) of SRS can be instructed. Further, the base station apparatus uses the DCI format B used for transmitting the downlink / uplink physical channel through the multi-antenna port, and instructs the mobile station apparatus to transmit SRS (request, trigger). )can do.

  In addition, in FIG. 5, the mobile station apparatus notified of the DCI format including the SRS transmission instruction from the base station apparatus can transmit SRS (A-SRS) to the base station apparatus aperiodically. In FIG. 5, the mobile station apparatus transmits the SRS to the base station apparatus in the (first) SRS subframe closest to the subframe four subframes after the subframe that received the DCI format including the SRS transmission instruction. It shows that.

  In FIG. 5, the mobile station apparatus transmits an SRS for a single antenna port or a multi-antenna port to the base station apparatus in accordance with the DCI format notified from the base station apparatus.

  For example, when the DCI format notified from the base station apparatus is a format used only for transmitting PDSCH through a single antenna port (that is, DCI format A), the mobile station apparatus uses a single antenna port. Is transmitted to the base station apparatus.

  Also, for example, when the DCI format notified from the base station apparatus is a format used only for transmitting PUSCH through a single antenna port (ie, DCI format A), the mobile station apparatus is single. SRS for the antenna port is transmitted to the base station apparatus.

  Further, for example, when the format of DCI notified from the base station device is a format used for transmitting PDSCH through the multi-antenna port (that is, DCI format B), the mobile station device uses the multi-antenna. SRS for the port is transmitted to the base station apparatus.

  In addition, for example, when the DCI format notified from the base station device is a format used for transmitting PUSCH through the multi-antenna port (that is, DCI format B), the mobile station device uses the multi-antenna. SRS for the port is transmitted to the base station apparatus.

  Here, when the format of DCI notified from the base station device is a format used only for transmitting PDSCH through a single antenna port (that is, DCI format A), the mobile station device uses a multi-antenna. You may transmit SRS with respect to a port to a base station apparatus.

  In addition, when the DCI format notified from the base station apparatus is a format used only for transmitting PUSCH through a single antenna port (that is, DCI format A), the mobile station apparatus uses a multi-antenna port. SRS may be transmitted to the base station apparatus.

  In addition, when the DCI format notified from the base station apparatus is a format used for transmitting PDSCH through the multi-antenna port (that is, DCI format B), the mobile station apparatus supports the single antenna port. You may transmit SRS to a base station apparatus.

  In addition, when the DCI format notified from the base station apparatus is a format used for transmitting PUSCH through a multi-antenna port (that is, DCI format B), the mobile station apparatus supports a single antenna port. You may transmit SRS to a base station apparatus.

  Here, in response to the DCI format (for example, DCI format A or DCI format B) notified from the base station apparatus, the mobile station apparatus transmits the SRS for the single antenna port or the SRS for the multi-antenna port. Whether to transmit is defined in advance according to the specification or the like, and can be known between the base station apparatus and the mobile station apparatus.

  Also, in response to the DCI format (for example, DCI format A or DCI format B) notified from the base station apparatus, the mobile station apparatus transmits SRS for a single antenna port or SRS for a multi-antenna port. Whether to do so may be set by the base station apparatus. For example, the base station apparatus determines whether the mobile station apparatus transmits an SRS for a single antenna port or an SRS for a multi-antenna port in accordance with the DCI format notified from the base station apparatus. Can be set specific to the mobile station apparatus.

  That is, in FIG. 5, the base station apparatus notifies the mobile station apparatus of DCI including an SRS transmission instruction, and the mobile station apparatus notified of this DCI corresponds to a single antenna port or multiple antennas corresponding to the DCI format. SRS for the antenna port is transmitted to the base station apparatus.

  Here, as described above, the DCI format A is arranged in the common search area (CSS) or the mobile station apparatus specific (USS) by the base station apparatus. Also, the DCI format B is arranged only in the mobile station device specific (USS) by the base station device. That is, the DCI format detected by the mobile station apparatus in the common search area (CSS) is only the DCI format A.

  That is, when the mobile station apparatus detects the DCI format notified from the base station apparatus in the common search area (CSS) (when DCI format A is detected), the mobile station apparatus transmits the SRS for the single antenna port to the base station apparatus. Send.

  Here, when the mobile station apparatus detects the DCI format notified from the base station apparatus in the common search area (CSS) (when DCI format A is detected), the mobile station apparatus transmits the SRS for the multi-antenna port to the base station apparatus. You may send to.

  In FIG. 5, in subframe n−2, the base station apparatus notifies DCI format B including an SRS transmission instruction to the mobile station apparatus. The mobile station apparatus notified of this DCI format B transmits SRS for the multi-antenna port to the base station apparatus in subframe n + 2. In FIG. 5, as an example, the mobile station apparatus indicates that the SRS for the multi-antenna port is transmitted to the base station apparatus corresponding to the DCI format B.

  Similar to FIG. 4, in FIG. 5, the SRS indicated by the diagonal line rising to the right (Tx # 1), the mesh line (Tx # 2), the horizontal line (Tx # 3), and the diagonal line rising to the left (Tx # 4) is The mobile station apparatus transmits the SRS for the multi-antenna port (for example, transmission antenna port Tx # 1, transmission antenna port Tx # 2, transmission antenna port Tx # 3, transmission antenna port Tx # 4) to the base station apparatus. It is shown that. For example, the mobile station apparatus uses cyclic shift for SRS for multi-antenna ports (for example, transmission antenna port Tx # 1, transmission antenna port Tx # 2, transmission antenna port Tx # 3, transmission antenna port Tx # 4). Can be multiplexed and transmitted to the base station apparatus.

  Similarly, in subframe n + 3, the base station apparatus notifies DCI format A including an SRS transmission instruction to the mobile station apparatus. The mobile station apparatus notified of this DCI format A transmits the SRS for the single antenna port to the base station apparatus in subframe n + 8. In FIG. 5, as an example, the mobile station apparatus indicates that the SRS corresponding to the single antenna port is transmitted to the base station apparatus corresponding to the DCI format A. Similarly to FIG. 4, in FIG. 5, SRS indicated by a vertical line (single antenna port) indicates that the mobile station apparatus transmits the SRS for the single antenna port to the base station apparatus.

  Similarly, in subframe n + 9, the base station apparatus notifies DCI format B including an SRS transmission instruction to the mobile station apparatus. The mobile station apparatus notified of this DCI format B transmits the SRS for the multi-antenna port to the base station apparatus in subframe n + 14.

  Similarly, in subframe n + 14, the base station apparatus notifies DCI format A including an SRS transmission instruction to the mobile station apparatus. The mobile station apparatus notified of this DCI format A transmits the SRS for the single antenna port to the base station apparatus in subframe n + 18.

  As described above, the base station apparatus notifies the mobile station apparatus of the DCI including the SRS transmission instruction, and the mobile station apparatus corresponds to the DCI format (for example, DCI format A or DCI format B). Thus, by transmitting the SRS for the single antenna port or the multi-antenna port to the base station apparatus, the mobile station apparatus can dynamically switch between SRS transmission for the single antenna port and SRS transmission for the multi-antenna port. .

  Also, the base station apparatus does not need to notify the mobile station apparatus by including information instructing single antenna port transmission or multi-antenna port transmission for the SRS in the DCI format, and more efficiently using radio resources. Single antenna port transmission or multi-antenna port transmission can be indicated.

  In addition, the mobile station apparatus dynamically switches and transmits the SRS for the single antenna port and the SRS for the multi-antenna port, so that the base station apparatus adapts to the channel state based on the SRS transmitted from the mobile station apparatus. Efficient scheduling can be performed. That is, when the base station apparatus and the mobile station apparatus transmit and receive physical channels using a single antenna port or a multi-antenna port, the base station apparatus can perform efficient scheduling.

  The embodiment described above is also applied to an integrated circuit / chip set mounted on a base station apparatus and a mobile station apparatus. Further, in the embodiment described above, each function in the base station device and a program for realizing each function in the mobile station device are recorded on a computer-readable recording medium and recorded on this recording medium. The base station apparatus and the mobile station apparatus may be controlled by causing the computer system to read and execute the program. 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. Further, the “computer-readable recording medium” is a medium that dynamically holds a program for a short time, such as a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line, In this case, a volatile memory in a computer system that serves as a server or a client in this case includes a program that holds a program for a certain period of time. 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.

  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 of the present invention are also within the scope of the claims. include.

100 base station apparatus 101 data control section 102 transmission data modulation section 103 radio section 104 scheduling section 105 channel estimation section 106 reception data demodulation section 107 data extraction section 108 upper layer 109 antenna 110 radio resource control section 200 mobile station apparatus 201 data control section 202 Transmission data modulation section 203 Radio section 204 Scheduling section 205 Channel estimation section 206 Reception data demodulation section 207 Data extraction section 208 Upper layer 209 Antenna 210 Radio resource control section

Claims (15)

A mobile communication system comprising a base station device and a mobile station device,
The base station device
Notifying the mobile station apparatus of a downlink control information format including information instructing single antenna port transmission or multi-antenna port transmission for a sounding reference signal,
The mobile station device
A mobile communication system, wherein a sounding reference signal for a single antenna port or a multi-antenna port is transmitted to the base station apparatus in accordance with the information. A mobile communication system comprising a base station device and a mobile station device,
The base station device
Notifying the mobile station apparatus of a downlink control information format including information instructing single antenna port transmission for a sounding reference signal,
The mobile station device
A mobile communication system, wherein a sounding reference signal for a single antenna port is transmitted to the base station apparatus according to the information. A mobile communication system comprising a base station device and a mobile station device,
The base station device
Notifying the mobile station apparatus of a downlink control information format including information instructing multi-antenna port transmission for a sounding reference signal,
The mobile station device
A mobile communication system, wherein a sounding reference signal for a multi-antenna port is transmitted to the base station apparatus according to the information. A mobile communication system comprising a base station device and a mobile station device,
The base station device
Notifying the mobile station apparatus of downlink control information including a sounding reference signal transmission instruction,
The mobile station device
A mobile communication system, wherein a sounding reference signal for a single antenna port or a multi-antenna port is transmitted to the base station apparatus in accordance with the format of the downlink control information. A mobile communication system comprising a base station device and a mobile station device,
The base station device
Notifying the mobile station apparatus of a downlink control information format including a sounding reference signal transmission instruction,
The mobile station device
If the downlink control information format includes a transmission instruction for the sounding reference signal, a sounding reference signal for a single antenna port is transmitted to the base station device,
The mobile communication system, wherein the downlink control information format is used only for the mobile station apparatus to transmit a physical uplink shared channel through a single antenna port. A mobile communication system comprising a base station device and a mobile station device,
The base station device
Notifying the mobile station apparatus of a downlink control information format including a sounding reference signal transmission instruction,
The mobile station device
When the downlink control information format includes the sounding reference signal transmission instruction, the sounding reference signal for the multi-antenna port is transmitted to the base station device,
The mobile communication system, wherein the downlink control information format is used for the mobile station apparatus to transmit a physical uplink shared channel through a multi-antenna port. A mobile communication system comprising a base station device and a mobile station device,
The base station device
Notifying the mobile station apparatus of a first downlink control information format or a second downlink control information format including a sounding reference signal transmission instruction;
The mobile station device
When the sounding reference signal transmission instruction is included in the first downlink control information format, a sounding reference signal for a single antenna port is transmitted to the base station device,
When the second downlink control information format includes a transmission instruction for the sounding reference signal, a sounding reference signal for a multi-antenna port is transmitted to the base station apparatus,
The first downlink control information format is used only when the mobile station apparatus transmits a physical uplink shared channel through a single antenna port,
The mobile communication system, wherein the second downlink control information format is used for the mobile station apparatus to transmit a physical uplink shared channel through a multi-antenna port. A base station apparatus in a mobile communication system composed of a base station apparatus and a mobile station apparatus,
A base station apparatus comprising: means for notifying the mobile station apparatus of a downlink control information format including information instructing single antenna port transmission or multi-antenna port transmission for a sounding reference signal. A mobile station apparatus in a mobile communication system composed of a base station apparatus and a mobile station apparatus,
Means for notifying the base station apparatus of a downlink control information format including information instructing single antenna port transmission or multi-antenna port transmission for a sounding reference signal;
Means for transmitting to the base station apparatus a sounding reference signal for a single antenna port or a multi-antenna port according to the information;
A mobile station apparatus comprising: A mobile station apparatus in a mobile communication system composed of a base station apparatus and a mobile station apparatus,
Means for notifying the base station apparatus of downlink control information including a sounding reference signal transmission instruction;
A mobile station apparatus, wherein a sounding reference signal for a single antenna port or a multi-antenna port is transmitted to the base station apparatus in accordance with the format of the downlink control information. A mobile station apparatus in a mobile communication system composed of a base station apparatus and a mobile station apparatus,
Means for notifying a first downlink control information format or a second downlink control information format including a sounding reference signal transmission instruction by the base station device;
Means for transmitting a sounding reference signal for a single antenna port to the base station apparatus when the first downlink control information format includes an instruction to transmit the sounding reference signal;
Means for transmitting a sounding reference signal for a multi-antenna port to the base station apparatus when the second downlink control information format includes an instruction to transmit the sounding reference signal;
The first downlink control information format is used only when the mobile station apparatus transmits a physical uplink shared channel through a single antenna port,
The mobile station apparatus, wherein the second downlink control information format is used for the mobile station apparatus to transmit a physical uplink shared channel through a multi-antenna port. A communication method of a base station apparatus in a mobile communication system composed of a base station apparatus and a mobile station apparatus,
A communication method comprising: notifying the mobile station device of a downlink control information format including information instructing single antenna port transmission or multi-antenna port transmission for a sounding reference signal. A mobile station apparatus communication method in a mobile communication system comprising a base station apparatus and a mobile station apparatus,
A downlink control information format including information instructing single antenna port transmission or multi-antenna port transmission for a sounding reference signal is notified by the base station apparatus,
According to the information, a sounding reference signal for a single antenna port or a multi-antenna port is transmitted to the base station apparatus. A mobile station apparatus communication method in a mobile communication system comprising a base station apparatus and a mobile station apparatus,
Downlink control information including a sounding reference signal transmission instruction is notified from the base station device,
Corresponding to the format of the downlink control information, a sounding reference signal for a single antenna port or a multi-antenna port is transmitted to the base station apparatus. A mobile station apparatus communication method in a mobile communication system comprising a base station apparatus and a mobile station apparatus,
The base station apparatus is notified of the first downlink control information format or the second downlink control information format including a sounding reference signal transmission instruction,
When the sounding reference signal transmission instruction is included in the first downlink control information format, a sounding reference signal for a single antenna port is transmitted to the base station device,
When the second downlink control information format includes a transmission instruction for the sounding reference signal, a sounding reference signal for a multi-antenna port is transmitted to the base station apparatus,
The first downlink control information format is used for the mobile station device to transmit a physical uplink shared channel using a single antenna port,
The second downlink control information format is used for the mobile station apparatus to transmit a physical uplink shared channel through a multi-antenna port.