JP2013055678A - Radio communication method, radio communication system, base station, mobile station and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To correctly reproduce CQI and ACK/NACK by reproducing (demodulating) PUCCH with a correct format.SOLUTION: A radio communication method includes: receiving allocation information indicative of a downward data channel; and through an upward control channel, transmitting at least one of control information indicative of a downward data reception state and quality information indicative of downlink communication quality. The control information and the quality information are transmitted through the upward control channel associated with each predetermined resource for the transmission of the control information and the quality information.

Description

  The present invention relates to a control signal transmission method and a reception method thereof in a wireless communication system.

  In the uplink in mobile communication, when a terminal that does not transmit uplink data also receives downlink data, an acknowledgment / negative acknowledgment (Acknowledgement / Negative Acknowledgment, which indicates whether or not downlink information has been received without error, hereinafter `` ACK / NACK ”), channel quality indication information (Channel Quality Indicator, hereinafter referred to as“ CQI ”) indicating downlink communication quality, and the like are transmitted using the uplink control channel.

  In LTE (Long Term Evolution), which is currently being standardized by 3GPP (3rd Generation Partnership Project), ACK / NACK and CQI are transmitted using ACK / NACK and CQI using an uplink control channel (Physical Uplink Control Channel: PUCCH). When transmitting / NACK, when transmitting CQI, when transmitting both ACK / NACK and CQI, the format of the control signal is different.

  FIG. 1 shows an example of (a) a format when transmitting only ACK / NACK, (b) a format when transmitting only CQI, and (c) a format when transmitting CQI and ACK / NACK.

  One slot is composed of seven long blocks (LB) at 0.5 ms, and one transmission time interval (TTI) is composed of two slots. The TTI is a time interval between a plurality of blocks transferred at a time between the physical layer and the MAC layer. As can be seen from FIG. 1, when CQI and ACK / NACK are transmitted simultaneously, the number and position of Long Blocks allocated to CQI and ACK / NACK are different from those in the case of ACK / NACK transmission or CQI transmission.

  FIG. 2 shows an example of LTE slot configuration. PUCCH is multiplexed at both ends of the system band. Actually, the PUCCH portion includes a reference signal (RS) for demodulating the PUCCH as shown in FIG. 1, but is omitted in FIG.

A CAZAC (Constant Amplitude Zero Auto-Correlation) sequence is used for the PUCCH and a reference signal for demodulating the PUCCH. The CAZAC sequence has a property that an autocorrelation value other than a constant amplitude and a phase difference of 0 is 0 in the time domain and the frequency domain. An example of a CAZAC sequence is a Zadoff-Chu sequence represented by the following equation (see Non-Patent Document 1).

  PUCCH user multiplexing methods include frequency division multiplexing (FDM) and code division multiplexing (CDM) (see Non-Patent Document 2). In CDM, a sequence in which each user performs a cyclic shift unique to the user on the same CAZAC sequence is used (see Non-Patent Document 3). Thereby, the orthogonality between users is maintained.

  FIG. 3 is a diagram for explaining the cyclic shift. When the unit cyclic shift amount is ΔT (long block length / 6 in the figure), the cyclic shift sequence i (i = 1, 2, 3, 4, 5, 6) is the last part ΔT × ( It is generated by shifting i-1) to the beginning. In order to maintain orthogonality between users, ΔT needs to be larger than the maximum delay path of the propagation path.

  Since ACK / NACK has a small amount of transmission information (basically 1 bit), it is possible to further perform block spreading on the time axis, thereby increasing the number of multiplexed users (see Non-Patent Document 4). FIG. 4 is a diagram illustrating an example of block spreading. In the figure, since there are three long blocks for the reference signal and four long blocks for the ACK / NACK, the reference signal is block-spread with a code length of 3, and the ACK / NACK is block-spread with a user-specific orthogonal code with a code length of 4. . The number of possible multiplexed users is the same as the code length, and here is a maximum of 3 from the sequence length of the reference signal with a short code length. Therefore, assuming that the number of users that can be multiplexed by cyclic shift is 6, this triple of 18 users can be multiplexed within the same frequency.

  It has been agreed that the PUCCH resources for transmitting ACK / NACK are associated with the index of the downlink L1 / L2 control signal on a one-to-one basis and do not perform signaling. It is a working assumption in standardization to associate one-to-one with the DL grant index for signaling downlink data resource allocation.

  FIG. 5 shows an example of a downstream frame format. The first 1 to 3 (2 in the figure) OFDM symbols are L1 / L2 control signals, and are composed of a downlink grant including downlink shared channel allocation information and an uplink grant including uplink shared channel allocation information. Downlink grants # 0 to #N in FIG. 5 include allocation resource information to DL Data # 0 to #N and an identifier of a user who should receive this.

  FIG. 6 shows an example of correspondence between Downlink grant and PUCCH. Note that indexing is not currently performed for PUCCH resources, but in the following description, indexing is given for PUCCH resources.

  A resource for transmitting a downlink grant is composed of a CCE (Control Channel Element), and a CCE index and a PUCCH index are associated one-to-one. As a result, it is not necessary to use signaling for PUCCH resource allocation, and the signaling overhead can be reduced.

  However, in the simultaneous transmission of CQI and ACK / NACK, if the terminal cannot detect the downlink data resource allocation information in the downlink L1 / L2 control signal, ACK / NACK is not transmitted and CQI is transmitted. become. In this case, the base station recognizes that CQI and ACK / NACK are transmitted, and demodulates in the format at the time of simultaneous transmission of CQI and ACK / NACK. However, in reality, only the CQI is transmitted, and the format differs between the transmission of only the CQI and the simultaneous transmission of the CQI and the ACK / NACK, and therefore the base station may erroneously determine ACK / NACK and CQI. is there.

  In order to solve this, there is a method in which the CQI transmission format is fixed regardless of the presence or absence of ACK / NACK, two reference sequences are allocated to one terminal, and ACK / NACK is notified depending on which reference sequence is selected. It has been proposed (see Non-Patent Document 5).

B. M. Popovic, “Generalized Chirp-Like Polyphase Sequences with Optimum Correlation Properties,” IEEE Transactions on Information Theory, Vol.38, No.4, pp1406-1409, July 1992. 3GPP R1-063448 Qualcomm, “Structure and Link Analysis UL Control Signaling,” November 2006. 3GPP R1-060925 Texas Instruments, “Comparison of Proposed Uplink Pilot Structures For SC-OFDMA,” March 2006. 3GPP R1-071293 Qualcomm Europe, “Link Analysis and Multiplexing Capability for UL ACK,” March 2007. 3GPP R1-072311 Nokia, “L Multiplexing of ACK / NACK and CQI from the same UE,” May 2007.

  However, the number of reference sequences that can be used is limited, and if two reference sequences are assigned to one base station, cell planning for assigning different reference sequences for each base station becomes difficult to reduce inter-cell interference. There is.

  Therefore, the problem to be solved by the present invention is that when the CQI and ACK / NACK are transmitted simultaneously and when the CQI is transmitted, the resource of the control channel used for transmission by the terminal is changed, and the resource is transmitted by either resource. It is an object of the present invention to provide a technique for solving the above problem by detecting whether or not a base station has detected.

  The present invention for solving the above-described problem is a wireless communication method that receives allocation information indicating channel allocation of downlink data, indicates control information indicating the reception status of the downlink data, and indicates downlink communication quality At least one of the quality information is transmitted by an uplink control channel, and the control information and the quality information are uplinks associated with predetermined resources allocated to transmit the control information and the quality information, respectively. It is transmitted by a control channel.

  In order to solve the above problems, the present invention provides a first means for receiving assignment information indicating downlink data channel assignment, control information indicating the reception status of the downlink data, and quality information indicating downlink communication quality. And a second means for transmitting at least one of the control information and the quality information using an uplink control channel, wherein the second means is associated with a predetermined resource allocated to transmit each of the control information and the quality information. It is characterized in that at least one of the control information and the quality information is transmitted using the uplink control channel provided.

  The present invention for solving the above-mentioned problem is a radio communication system including a mobile station, wherein the mobile station receives first allocation information indicating channel allocation of downlink data, and the downlink data A second means for transmitting at least one of control information indicating a reception status and quality information indicating a downlink communication quality using an uplink control channel, wherein the second means includes the control information and the quality information. And transmitting at least one of the control information and the quality information using an uplink control channel associated with a predetermined resource allocated to transmit each of the control information and the quality information.

  The present invention for solving the above-mentioned problems is a base station, wherein a transmission means for transmitting allocation information indicating channel allocation of downlink data, control information indicating the reception status of the downlink data, and downlink communication quality Receiving means for receiving from the mobile station at least one of the quality information indicating the control information, the receiving means is a predetermined resource allocated to transmit each of the control information and the quality information And receiving at least one of the control information and the quality information through an uplink control channel associated with.

  Depending on the signal transmission format, the mobile station selects the control channel resource and transmits the signal, and the base station detects and reproduces (demodulates) the control channel resource from which the signal is transmitted. Thus, it is possible to reproduce (demodulate) a signal transmitted through the control channel in the correct format.

FIG. 1 is a diagram for explaining a format of PUCCH in LTE. FIG. 2 is an example of an uplink physical channel configuration in LTE. FIG. 3 is a schematic diagram when a cyclic shift is added to the CAZAC sequence. FIG. 4 is a format diagram showing an example of a PUCCH slot configuration. FIG. 5 is an example of a downlink physical channel configuration in LTE. FIG. 6 is a correspondence example of PDCCH downlink grant and PUCCH in LTE. FIG. 7 is a block diagram showing a schematic configuration of a base station in the mobile radio system according to the first embodiment of the present invention. FIG. 8 is a block diagram showing a schematic configuration of a mobile station in the mobile radio system according to the first embodiment of the present invention. FIG. 9 is an operation flowchart of the control unit of the mobile station that determines the PUCCH for transmitting control information and the type of control information according to the first embodiment of the present invention. FIG. 10 is a first example of an operation flowchart of the PUCCH reproduction unit of the base station that determines the type of PUCCH and control information to be reproduced according to the first embodiment of the present invention. FIG. 11 is a second example of an operation flowchart of the PUCCH reproduction unit of the base station that determines the type of PUCCH and control information to be reproduced according to the first embodiment of the present invention. FIG. 12 is a block diagram showing a schematic configuration of a mobile station in the mobile radio system according to the second embodiment of the present invention. FIG. 13 is an operation flowchart of a control unit of a base station that determines allocation of a PDCCH for transmitting a downlink grant according to the second embodiment of the present invention. FIG. 14 shows an example of correspondence between PDCCH CCEs and PUCCHs.

  First, an outline of the present invention will be described.

  A base station (also referred to as Node B) notifies downlink data channel allocation information to a user terminal to which downlink data is allocated using a downlink grant of a downlink L1 / L2 control signal. Also, a request for periodic report of CQI is notified by higher layer signaling.

  FIG. 14 shows an example of correspondence between PDCCH CCEs and PUCCHs. Using this, an example of signaling between a base station and a mobile station is shown. When the user terminal (mobile station) detects the downlink grant, the CCE (Control Channel of the downlink grant) is associated with the ACK / NACK PUCCH (# 0- # 5) for each CCE in FIG. This is a PUCCH resource having an index that is in one-to-one correspondence with the index of (Element), and is transmitted as a control signal with a TTI that notifies both ACK / NACK or CQI and ACK / NACK.

  When a downlink grant is not detected, a PUCCH resource having an index that is in one-to-one correspondence with the index notified by higher layer signaling, such as CUCI PUCCH (# 6- # 11) in FIG. To transmit as a control signal by TTI that notifies CQI. Note that indexing is not currently performed for PUCCH resources, but in the following description, indexing is given for PUCCH resources.

  When the received control signal detects a PUCCH of a resource having an index that is one-to-one associated with the CCE index of the downlink grant, the base station recognizes that the user terminal has been able to detect the downlink grant. Then, the control signal is determined to be an ACK format or CQI + ACK format control signal, and based on the scheduling information performed by the local station, it is determined in which format the PUCCH is transmitted and demodulated (demodulated). ) On the other hand, when the PUCCH having the index notified by higher layer signaling is detected, the user terminal recognizes that the downlink grant has not been detected, and determines that it is a control signal in the CQI format, and is a signal received on the PUCCH. Is reproduced (demodulated).

  Therefore, the base station determines whether or not the user terminal has detected a downlink grant based on the PUCCH resource index, and can reproduce (demodulate) CQI + ACK and CQI signals in the correct format.

  Hereinafter, embodiments of the present invention will be described in detail.

  The wireless communication system of the present invention has a base station and a mobile station. 7 and 8 are block diagrams showing the main configurations of the base station and mobile station in the first embodiment of the present invention, respectively. In FIG. 7, it is assumed that the base station 10 accommodates a plurality of mobile stations 20 (UE1, UE2,...).

  In FIG. 7, the radio communication control unit 101 controls communication with a plurality of mobile stations UE in accordance with, for example, the predetermined frequency / time multiplexing configuration already shown in FIG. For example, the radio communication control unit 101 separates multiplexed signals received from a plurality of mobile stations UE and outputs them to a PUSCH (Physical Uplink Shared Channel) reproduction unit 102, a PUCCH reproduction unit 103, and a CQI measurement unit 104, respectively. In addition, various transmission signals are multiplexed according to a predetermined frequency / time multiplexing configuration from the PDCCH (Physical Downlink Control CHannel) generation unit 107, the PDSCH (Physical Downlink Shared CHannel) generation unit 108, and the reference signal generation unit 109 to the plurality of mobile stations 20. Send.

  The CQI measurement unit 104 receives the reference signal from each mobile station, measures the uplink channel quality, and outputs it to the control unit 105 and the scheduler 106.

  The scheduler 106 performs channel-dependent frequency scheduling using the measured uplink channel quality of each mobile station under the control of the control unit 105. The scheduler 106 outputs the downlink grant, which is downlink PDSCH allocation information, and the uplink grant, which is uplink PUSCH allocation information, to the PDCCH generation unit 107 and the PDSCH generation unit 108 via the control unit 105. The downlink grant output to the PDCCH generation unit 107 is transmitted to each mobile station by the radio communication control unit 101 as a downlink control signal. The PDSCH generation unit 108 transmits the downlink data indicated by the downlink grant to each mobile station via the radio communication control unit 101.

  When the scheduler 106 has PUCCH allocation information for receiving a CQI report that is periodically downlink communication quality information, the control unit 105 also outputs the PUCCH allocation information to the PDSCH generating unit 108 and outputs the PUCCH for the CQI report. The allocation information is transmitted to each mobile station by higher layer signaling as part of the PDSCH by the PDSCH generation unit 108 and the radio communication control unit 101.

  The PUCCH reproducing unit 103 reproduces the PUCCH under the control unit 105 based on the information scheduled by the scheduler 106.

  In FIG. 8, the PDCCH reproducing unit 202 reproduces a downlink grant and an uplink grant using the multiplexed signal received from the base station 10 by the wireless communication unit 201 as an input, and the PDSCH reproducing unit 203 performs the PDSCH based on the reproduced downlink grant. The downlink data transmitted in step 1, PUCCH allocation information for CQI reports, and the like are extracted.

  The control unit 204 detects a downlink grant from the data output from the PDCCH reproduction unit 202. Also, the control unit 204 performs various controls for allocating PUCCH used for uplink control signal transmission according to the detected downlink grant and PUCCH allocation information for the CQI report reproduced by the PDSCH reproducing unit 203.

  The PUSCH generation unit 205 generates a PUSCH data signal based on the regenerated Uplink grant obtained through the control unit 204, converts the PUSCH data signal into the frequency domain by the discrete Fourier transform unit DFT 209, and then selects the signal selection unit 210. Output to.

  The PUCCH generation unit 206 generates a PUCCH control signal based on the determination of the control unit 204, and the CAZAC sequence spreading unit 207 spreads the PUCCH control signal using the frequency domain CAZAC sequence input from the CAZAC sequence generation unit 208. To do.

  CAZAC sequence generation unit 208 generates a frequency-domain CAZAC sequence and outputs the CAZAC sequence to CAZAC sequence spreading unit 207 and signal selection unit 210.

  Under the control of the control unit 204, the signal selection unit 210 sequentially selects a PUSCH data signal from the DFT 209, a PUCCH control signal from the CAZAC sequence spreading unit 207, and a reference signal from the CAZAC sequence generation unit 208, and Direction division multiplexing is performed and output to the subcarrier mapping unit 211. The subcarrier mapping unit 211 maps the frequency domain signal input from the signal selection unit 210 to the subcarriers of the allocated resource block, and converts it into a time domain signal by the inverse Fourier transform unit IFFT212.

  Subsequently, the cyclic shift unit 213 performs a cyclic shift of the CAZAC sequence under the control of the control unit 204. That is, in the case of PUSCH, the cyclic shift amount is set to 0 and no cyclic shift is performed. In the case of the PUCCH and the reference signal, the control unit 204 instructs six patterns of cyclic shift amounts, and adds a cyclic shift to the CAZAC signal in the time domain. Subsequently, the cyclic prefix adding unit 214 adds a cyclic prefix to the time domain signal thus obtained and outputs the signal to the wireless communication unit 201.

  FIG. 9 is a flowchart regarding selection of PUCCH and determination of the type of information to be generated in the control unit 204 of the mobile station 20 in the first embodiment of the present invention. In this case, the PUCCH allocation information for the CQI periodic report has already been notified from the base station, and based on this information, whether the control unit 204 should transmit the CQI as control information in the TTI to be transmitted from now on. Shall be judged.

  In FIG. 9, the control unit 204 of the mobile station 20 detects a downlink grant (step 300).

  When a downlink grant is detected, the signal selection unit 210 is notified to transmit a signal using a PUCCH resource having an index that is in one-to-one correspondence with the CCE (Control Channel Element) index of the downlink grant. (Step 301).

  Then, it is determined whether or not to transmit CQI as control information in the TTI to be transmitted (step 302). In the case of TTI that transmits CQI, it is determined that CQI + ACK / NACK is generated as control information, and PUCCH The generation unit 206 is notified (step 305), and if it is not a TTI for transmitting CQI, it is determined to generate ACK / NACK as control information and notified to the PUCCH generation unit 206 (step 306). Note that an ACK is generated when the downlink data indicated by the downlink grant can be normally extracted from the PDSCH, and a NACK is generated when the downlink data cannot be extracted normally.

  On the other hand, if a downlink grant is not detected in step 300, it is determined whether to transmit CQI as control information in the TTI to be transmitted (step 303). In the case of TTI transmitting CQI, notification is made by higher layer signaling. The signal selection unit 210 is notified to transmit using the PUCCH resource for CQI transmission having an index that is one-to-one correspondence with the index that has been created (step 304), and the CQI is generated as control information The decision is made and notified to the PUCCH generation unit 206 (step 307).

  On the other hand, if it is determined in step 303 that it is not a TTI that transmits a CQI, the process ends without performing anything.

  FIG. 10 is a first example of a flowchart regarding PUCCH reproduction processing in the PUCCH reproduction unit 103 of the base station 10 in the first embodiment of the present invention.

  In FIG. 10, PUCCH reproducing section 103 of base station 10 determines whether or not the TTI is for transmitting a control signal including ACK / NACK (step 400). This determination is made based on whether or not the control signal is received at the timing when ACK / NACK for the downlink data transmitted by the base station 10 is transmitted. The scheduler 106 transmits the downlink data to the mobile station 20. The control unit 105 controls the PUCCH reproduction unit 103 based on information on scheduling performed at the time.

  If it is determined in step 400 that the TTI is to transmit a control signal including ACK / NACK, ACK / NACK or CQI + ACK / NACK (index associated with the CCE index of the downlink grant in a one-to-one correspondence. In order to know whether or not the control information includes the information of the PUCCH resource having the PUCCH resource), the cyclic shift sequence to be used by the PUCCH resource used for transmitting the ACK / NACK and the control information are transmitted. A correlation value with the cyclic shift sequence used for spreading in the PUCCH is calculated (step 401). This is because the scheduler 106 schedules a cyclic shift sequence to be used when transmitting downlink data to the mobile station 20, and the control unit 105 knows the information in advance, so this information is used. Calculate the correlation. In addition, PUCCH here is PUCCH which has the index matched with CCE (Control Channel Element) index of Downlink grant used when assigning PDSCH.

  Next, it is determined whether or not the correlation calculation result is equal to or greater than a predetermined threshold (step 402).

  If it is determined that the value is equal to or greater than the threshold, it is determined that the control information includes ACK / NACK or CQI + ACK / NACK information, and then it is determined whether the control information is CQI + ACK / NACK. (Step 403). This determination is made based on whether or not the control information is received at the timing when the CQI is transmitted based on a request for a periodic report of CQI transmitted by the base station 10. The control unit 105 controls the PUCCH reproduction unit 103 based on information on scheduling performed when transmitting data to the mobile station 20.

  In the case of a TTI in which CQI is transmitted, it is reproduced as control information transmitted in the format of CQI + ACK / NACK using a PUCCH resource having an index that is one-to-one associated with the CCE index of the downlink grant ( Step 405), if the CQI is not a TTI to be transmitted, playback is performed as control information transmitted in the ACK / NACK format using the PUCCH resource having a one-to-one correspondence with the CCE index of the downlink grant. (Step 406).

  On the other hand, if it is determined in step 400 that ACK / NACK is not included, or if it is determined in step 402 that the correlation value is less than the threshold, it is determined whether or not the CTI is a TTI to be transmitted. (Step 404). This determination is made based on whether or not the CQI is transmitted at the timing when the CQI is transmitted based on a request for a periodic report of the CQI transmitted by the base station 10. The control unit 105 controls the PUCCH reproduction unit 103 based on information on scheduling performed when transmitting to the mobile station 20.

  In the case of a TTI in which a control signal including CQI is transmitted, a PUCCH for CQI transmission having an index notified by higher layer signaling is reproduced as CQI (step 407), and a TTI in which a control signal including CQI is transmitted If not, the process ends without doing anything.

  In step 400, the PUCCH reproduction unit 103 of the base station 10 determines whether or not the TTI is a control signal including ACK / NACK, but the correct format can be obtained without performing this determination. Thus, it becomes possible to reproduce (demodulate) the PUCCH.

  FIG. 11 is a second example of a flowchart regarding the PUCCH reproduction processing in the PUCCH reproduction unit 103 of the base station 10 in the first embodiment of the present invention.

  In FIG. 11, PUCCH reproduction section 103 of base station 10 determines whether or not it is a TTI that receives a control signal including ACK / NACK as in step 400 (step 500).

  If it is determined in step 500 that the TTI is for receiving a control signal including ACK / NACK, it is determined whether the TTI is for receiving a control signal including CQI (step 501). This determination is made based on whether a control signal including the CQI is received based on a request for a periodic report of CQI transmitted by the base station 10, and the scheduler 106 receives the downlink data. Is performed by the control unit 105 controlling the PUCCH reproduction unit 103 based on information on scheduling performed when transmitting the message to the mobile station 20.

  In the case of a TTI that receives a control signal including CQI, CQI or CQI + ACK / NACK (PUCCH resource having an index corresponding to the CCE index of Downlink grant, or the CCE index of Downlink grant. In order to know whether it is control information of a PUCCH having an index corresponding one-to-one with a cyclic shift sequence to be used by PUCCH resources used for transmission of ACK / NACK, and transmission of CQI Correlation values A and B between the cyclic shift sequences to be used by the PUCCH resources to be used and the cyclic shift sequences used for spreading in the PUCCH to which this control information is transmitted are calculated (step 502). . This is because the scheduler 106 schedules a cyclic shift sequence to be used when transmitting downlink data to the mobile station 20, and the control unit 105 knows the information in advance, so this information is used. Calculate the correlation.

  Next, it is determined whether or not the correlation value A is greater than the correlation value B (step 503). If the correlation value A is greater than the correlation value B, it is associated one-to-one with the CCE index of the downlink grant. It reproduces as control information transmitted in the format of CQI + ACK / NACK using the PUCCH resource having index (step 506), and when correlation value A is equal to or less than correlation value B, the index notified by higher layer signaling Is reproduced as control information transmitted in the CQI format using the PUCCH resource for CQI transmission having (step 507). If it is determined in step 501 that the TTI is not a TTI that receives a control signal including a CQI, the ACK / NACK of the ACK / NACK using the PUCCH resource having an index that is one-to-one associated with the CCE index of the downlink grant It is reproduced as transmitted in the format (step 505).

  On the other hand, if it is determined in step 500 that it is not the timing to receive ACK / NACK, it is determined whether or not it is a TTI that receives a control signal including CQI (step 504). This determination is made based on whether or not the control information is received at the timing when the CQI is transmitted based on a request for a periodic report of CQI transmitted by the base station 10. The control unit 105 controls the PUCCH reproduction unit 103 based on information on scheduling performed when transmitting data to the mobile station 20.

  In the case of a TTI that receives a control signal including CQI, it is reproduced as control information transmitted in the CQI format using the PUCCH resource for CQI transmission having the index notified by higher layer signaling (step 507), If it is not a TTI that receives a control signal including CQI, the process ends without performing anything.

  In the above embodiment, as an example in which PUCCH allocation is notified by higher layer signaling, a case where CQI is transmitted using PUCCH is described. However, the application of the present invention is not limited to this, and PUCCH is used. In general, the present invention can be applied to the case where information is periodically transmitted. For example, ACK / NACK for an application to which PDSCH resources such as VoIP are periodically allocated is one example of information periodically transmitted using PUCCH. As a PUCCH allocation method for periodically transmitting ACK / NACK, higher layer signaling may be used.

  ACK / NACK and periodic ACK / NACK for PDSCH scheduled by DL grant are different in transmission format between (a) each transmitting and (b) transmitting simultaneously with one PUCCH. Since the former transmits only 1-bit information and the latter transmits 2-bit information, for example, the former uses BPSK and the latter uses QPSK.

  When a user terminal detects a DL grant when transmitting a periodic ACK / NACK on PUCCH, it uses PUCCH having an index that is in one-to-one correspondence with the CCE index of the downlink grant. When both ACK / NACK are transmitted using QPSK and DL grant is not detected, periodic ACK / NACK is transmitted using BPSK on PUCCH having the index notified by higher layer signaling. If the base station detects a PUCCH having a one-to-one correspondence with the CCE index of the downlink grant, the base station determines that the format uses QPSK, reproduces (demodulates) the PUCCH, When a PUCCH having an index notified by signaling is detected, it is determined that the format uses BPSK, and the PUCCH is reproduced (demodulated). Therefore, the base station determines whether or not the user terminal has detected the DL grant based on the PUCCH index, and can reproduce (demodulate) the data in the correct format.

  With the above processing, the mobile station selects a different PUCCH when transmitting CQI and ACK / NACK at the same time and when transmitting CQI, and the base station detects which PUCCH is transmitted. It becomes possible to reproduce (demodulate) the PUCCH in the format.

  FIG. 12 is a block diagram showing the main configuration of the mobile station in the second embodiment of the present invention. As in the first embodiment, the base station has the configuration shown in FIG. 7. The base station and mobile station components similar to those in the first embodiment are given the same reference numerals, and detailed description will be given. Is omitted. A major difference of the present embodiment from the first embodiment is that the number of multiplexed PUCCH resources for ACK / NACK transmission is increased by applying block spreading on the time axis.

  In FIG. 12, with the multiplexed signal received from the base station 10 by the wireless communication unit 201 as an input, the PDCCH reproduction unit 202 reproduces the downlink grant and the uplink grant, and the PDSCH reproduction unit 203 performs the PDSCH based on the reproduced downlink grant. The downlink data transmitted in step 1, PUCCH allocation information for CQI reports, and the like are extracted. The control unit 204 performs various controls for allocating the PUCCH used for uplink control signal transmission according to the downlink grant and the PUCCH allocation information for CQI report notified from the base station.

  The PUSCH generation unit 205 generates a PUSCH data signal based on the regenerated Uplink grant obtained through the control unit 204, converts the PUSCH data signal into the frequency domain by the discrete Fourier transform unit DFT 209, and then selects the signal selection unit 210. Output to.

  The PUCCH generation unit 206 generates a PUCCH control signal based on the determination of the control unit 204, and the CAZAC sequence spreading unit 207 spreads the PUCCH control signal using the frequency domain CAZAC sequence input from the CAZAC sequence generation unit 208. To do.

  CAZAC sequence generation unit 208 generates a frequency-domain CAZAC sequence and outputs the CAZAC sequence to CAZAC sequence spreading unit 207 and block spreading unit 603.

  Block spreading section 601 performs block spreading of the PUCCH spreading control signal using the spreading code from block spreading code generating section 602 and outputs the result to signal selecting section 210. Block spreading section 603 performs block spreading of the frequency domain CAZAC sequence input from CAZAC sequence generating section 208 using the spreading code from block spreading code generating section 602, and outputs the result to signal selecting section 213.

  The block spreading code generation unit 602 generates codes used for block spreading of the PUCCH and the reference signal.

  Under the control of the control unit 204, the signal selection unit 210 sequentially selects the PUSCH data signal from the DFT 209, the PUCCH control signal from the block spreading unit 601, and the reference signal from the block spreading unit 603, in the time direction. Division multiplexing is performed and output to the subcarrier mapping unit 211. The subcarrier mapping unit 211 maps the frequency domain signal input from the signal selection unit 213 to the subcarrier of the allocated resource block, and converts it into a time domain signal by the inverse Fourier transform unit IFFT212.

  Subsequently, the cyclic shift unit 213 performs a cyclic shift of the CAZAC sequence under the control of the control unit 204. That is, in the case of PUSCH, the cyclic shift amount is set to 0 and no cyclic shift is performed. In the case of the PUCCH and the reference signal, the control unit 204 instructs six patterns of cyclic shift amounts, and adds a cyclic shift to the CAZAC signal in the time domain. Subsequently, the cyclic prefix adding unit 214 adds a cyclic prefix to the time domain signal thus obtained and outputs the signal to the wireless communication unit 201.

  As described above, PUCCH user multiplexing using block spreading on the time axis can be performed. However, block spreading is applied when ACK / NACK is transmitted. When CQI is transmitted, when CQI + ACK / NACK is transmitted, the arrangement of the reference signal and the control signal in the slot is different from that when ACK / NACK is transmitted. Therefore, orthogonalization cannot be performed by block spreading. Therefore, the PUCCH resource for transmitting CQI + ACK / NACK, the PUCCH resource for transmitting CQI, and the PUCCH resource for transmitting ACK / NACK must have different frequencies and / or cyclic shifts. is there. In the present invention, the PUCCH resource for transmitting CQI + ACK / NACK and the PUCCH resource for transmitting ACK / NACK are associated one-to-one with the CCE index of the downlink grant. Therefore, when the PDCCH for transmitting the downlink grant is allocated in the base station, CQI + ACK / NACK transmitted using the PUCCH resource that is associated with the CCE index of the downlink grant in a one-to-one relationship is transmitted. It is necessary to consider beforehand that the PUCCH resource to be transmitted and the PUCCH resource to transmit ACK / NACK are orthogonal.

  FIG. 13 is a flowchart related to PDCCH resource allocation for transmitting a downlink grant in the control unit 105 of the base station 10 in the second embodiment of the present invention. Here, the PUCCH allocation information for the CQI periodic report is already notified to the mobile station 20, and the control unit 105 knows the timing when the CQI is transmitted by the scheduling information of the scheduler 106. It shall be.

  In FIG. 13, the control unit 105 of the base station 10 determines whether or not to perform PDSCH allocation (step 700). This is determined by whether there is downlink data to be transmitted to the mobile station 20.

  When the PDSCH is allocated, it is determined whether or not ACK / NACK and CQI, which are the reception status of downlink data of this PDSCH, are transmitted with the same TTI (step 701). This is because the control unit 105 knows the timing at which the CQI is transmitted from the scheduling information of the scheduler 106, and thereby determines whether ACK / NACK and CQI are transmitted as control information.

  When transmitted by the same TTI, the mobile station 20 uses a CCE (Control Channel) of a downlink grant such that the PUCCH resource used for CQI + ACK / NACK transmission is orthogonal to the PUCCH resource used for ACK / NACK transmission. Element) is assigned to PDCCH (step 702).

  On the other hand, if transmission is not performed with the same TTI, the CCE (Control Channel) of the downlink grant in which the mobile station 20 uses the PUCCH resource used for ACK / NACK transmission orthogonal to the PUCCH resource used for CQI + ACK / NACK transmission. Element) index is assigned to PDCCH (step 703).

  In this way, if the PCECH resource used for CQI + ACK / NACK transmission and the PUCCH resource used for ACK / NACK transmission are orthogonal to each other, the base station side assigns the CCE index of the downlink grant in advance. The station 20 can orthogonalize the PUCCH resource used for transmitting CQI + ACK / NACK and the PUCCH resource used for transmitting ACK / NACK without performing signaling.

  The terminal of the present invention described above can be configured by hardware as is apparent from the above description, but can also be realized by a computer program. In this case, functions and operations similar to those of the above-described embodiment are realized by a processor that operates according to a program stored in the program memory. Note that only a part of the functions of the above-described embodiment can be realized by a computer program.

(Appendix 1)
A wireless communication method,
When the allocation information indicating the allocation of the downlink data channel is detected, at least the reception status of the downlink data indicated by the allocation information is indicated by using the uplink control channel resource associated with the allocation information resource. A wireless communication method characterized by transmitting control information.

(Appendix 2)
When the allocation information is detected, it is determined whether it is timing to transmit quality information indicating downlink communication quality,
When it is determined that it is time to transmit quality information, the control information and the quality information are transmitted using resources of an uplink control channel associated with the resource of the allocation information. The wireless communication method according to 1.

(Appendix 3)
If the allocation information is not detected, it is determined whether it is timing to transmit quality information indicating downlink communication quality;
If it is determined that it is time to transmit the quality information, the quality information is transmitted using an uplink control channel resource that is allocated in advance for the transmission of the quality information. The wireless communication method according to 2.

(Appendix 4)
If the allocation information is not detected, determine whether it is time to transmit periodic control information;
When it is determined that it is time to transmit the periodic control information, the periodic control information is transmitted by using an uplink control channel resource allocated in advance for the transmission of the periodic control information. The wireless communication method according to Supplementary Note 1 or Supplementary Note 2, wherein:

(Appendix 5)
The wireless communication method according to any one of appendix 1 to appendix 4, wherein the transmitted information is reproduced based on a format determined according to a determination result of a resource used for the transmitted information. .

(Appendix 6)
Correlation between a spreading code to be used for transmission of control information indicating the reception status of downlink data and a spreading code used for control information transmitted on the uplink control channel resource associated with the resource of the allocation information The wireless communication method according to appendix 5, wherein the resource is determined based on a relationship.

(Appendix 7)
Correlation between a spreading code to be used for transmission of control information indicating the reception status of downlink data and a spreading code used for control information transmitted on the uplink control channel resource associated with the resource of the allocation information Control information transmitted on the uplink control channel resources allocated in advance for transmission of the quality information or the periodic control information and the spreading code to be used for transmission of control information indicating the relationship and the reception status of downlink data 6. The wireless communication method according to appendix 5, wherein the resource is determined based on a correlation with a spreading code used for the transmission.

(Appendix 8)
An uplink control channel resource used when transmitting control information indicating downlink data reception status and quality information indicating downlink communication quality, and an uplink control channel resource used when transmitting the control information; The wireless communication method according to any one of appendix 2 to appendix 7, wherein the allocation information is determined so that the orthogonality is orthogonal.

(Appendix 9)
A wireless communication system,
Detecting means for detecting allocation information indicating channel allocation of downlink data;
When the allocation information is detected, a transmission for transmitting at least control information indicating the reception status of the downlink data indicated by the allocation information, using the resource of the uplink control channel associated with the resource of the allocation information And a wireless communication system.

(Appendix 10)
When the allocation information is not detected, the detection unit determines whether it is timing to transmit quality information indicating downlink communication quality;
When it is determined that it is time to transmit the quality information, the transmission means transmits the quality information using an uplink control channel resource allocated in advance for the transmission of the quality information. The wireless communication system according to appendix 9.

(Appendix 11)
The detection means determines whether it is a timing to transmit periodic control information when the allocation information is not detected,
When it is determined that it is time to transmit the periodic control information, the transmission means uses the uplink control channel resource allocated in advance to transmit the periodic control information, and performs the periodic control. The wireless communication system according to appendix 9, wherein information is transmitted.

(Appendix 12)
The detection means, when detecting the allocation information, determines whether it is a timing to transmit quality information indicating downlink communication quality;
When it is determined that it is time to transmit quality information, the transmission means transmits the control information and the quality information using an uplink control channel resource associated with the resource of the allocation information. The wireless communication system according to any one of appendix 9 to appendix 11, characterized by

(Appendix 13)
13. The wireless communication system according to any one of appendix 9 to appendix 12, wherein the transmitted information is reproduced based on a format determined according to a determination result of a resource used for the transmitted information. .

(Appendix 14)
Correlation between a spreading code to be used for transmission of control information indicating the reception status of downlink data and a spreading code used for control information transmitted on the uplink control channel resource associated with the resource of the allocation information The wireless communication system according to claim 13, wherein the resource is determined based on a relationship.

(Appendix 15)
Correlation between a spreading code to be used for transmission of control information indicating the reception status of downlink data and a spreading code used for control information transmitted on the uplink control channel resource associated with the resource of the allocation information Control information transmitted on the uplink control channel resources allocated in advance for transmission of the quality information or the periodic control information and the spreading code to be used for transmission of control information indicating the relationship and the reception status of downlink data 14. The wireless communication system according to appendix 13, wherein the resource is determined based on a correlation with a spreading code used for the transmission.

(Appendix 16)
An uplink control channel resource used when transmitting control information indicating downlink data reception status and quality information indicating downlink communication quality, and an uplink control channel resource used when transmitting the control information; The wireless communication system according to any one of Supplementary Note 12 to Supplementary Note 15, further comprising: a determination unit that determines resources of the allocation information so that the two are orthogonal to each other.

(Appendix 17)
A mobile station,
Detecting means for detecting allocation information indicating channel allocation of downlink data;
When the allocation information is detected, a transmission for transmitting at least control information indicating the reception status of the downlink data indicated by the allocation information, using the resource of the uplink control channel associated with the resource of the allocation information And a mobile station.

(Appendix 18)
The detection means, when detecting the allocation information, determines whether it is a timing to transmit quality information indicating downlink communication quality;
When it is determined that it is time to transmit quality information, the transmission means transmits the control information and the quality information using an uplink control channel resource associated with the resource of the allocation information. The mobile station according to appendix 17, characterized by:

(Appendix 19)
When the allocation information is not detected, the detection unit determines whether it is timing to transmit quality information indicating downlink communication quality;
When it is determined that it is time to transmit the quality information, the transmission means transmits the quality information using an uplink control channel resource allocated in advance for the transmission of the quality information. The mobile station according to Supplementary Note 17 or Supplementary Note 18.

(Appendix 20)
The detection means determines whether it is a timing to transmit periodic control information when the allocation information is not detected,
When it is determined that it is time to transmit the periodic control information, the transmission means uses the uplink control channel resource allocated in advance to transmit the periodic control information, and performs the periodic control. 19. The mobile station according to appendix 17 or appendix 18, wherein the mobile station transmits information.

(Appendix 21)
A base station,
A discriminating means for discriminating the resource used for transmitting the transmitted information;
A base station, comprising: reproducing means for reproducing the transmitted information based on a format determined according to the determination result.

(Appendix 22)
The determination means is transmitted using a spreading code to be used for transmission of control information indicating downlink data reception status and an uplink control channel resource associated with an allocation information resource indicating the downlink data channel allocation. The base station according to appendix 21, wherein the resource is determined based on a correlation with a spreading code used in the received information.

(Appendix 23)
The determination means is transmitted using a spreading code to be used for transmission of control information indicating downlink data reception status and an uplink control channel resource associated with an allocation information resource indicating the downlink data channel allocation. Correlation with the spreading code used in the received information, spreading code to be used for transmission of control information indicating the reception status of downlink data, and uplink assigned in advance for transmission of the control information to be transmitted The base station according to appendix 21, wherein the resource is discriminated based on a correlation with a spreading code used in control information transmitted using a control channel resource.

(Appendix 24)
Uplink control channel resources used when control information indicating downlink data reception status and quality information indicating downlink communication quality are transmitted, and uplink control channel used when the control information is transmitted 24. The base station according to any one of appendix 21 to appendix 23, further comprising a determination unit that determines an allocation information resource indicating downlink data channel allocation so that the resource is orthogonal.

(Appendix 25)
When the determination result indicates that the resource of the uplink control channel associated with the resource of the allocation information is the resource used for the transmitted information, the reproducing means indicates the reception status of downlink data. Play as a format that includes control information
When the determination result is that the resource of the uplink control channel allocated in advance for the transmission of the quality information is the resource used for the transmitted information, the control indicating the reception status of the downlink data 25. The base station according to appendix 22 to appendix 24, which is reproduced as a format not including information.

(Appendix 26)
A program of a mobile station, wherein the program
Detection processing for detecting allocation information indicating channel allocation of downlink data;
When the allocation information is detected, a transmission for transmitting at least control information indicating the reception status of the downlink data indicated by the allocation information, using the resource of the uplink control channel associated with the resource of the allocation information A program characterized by causing processing to be executed.

(Appendix 27)
When the detection process detects the allocation information, it further determines whether it is timing to transmit quality information indicating downlink communication quality;
When it is determined that it is time to transmit the quality information, the transmission process transmits the control information and the quality information using an uplink control channel resource associated with the resource of the allocation information. Item 27. The program according to item 26.

(Appendix 28)
If the allocation information is not detected, the detection process further determines whether it is timing to transmit quality information indicating downlink communication quality;
When it is determined that the transmission process is a timing for transmitting the quality information, the quality information is transmitted using an uplink control channel resource allocated in advance for the transmission of the quality information. The program according to Supplementary Note 26 or Supplementary Note 25.

(Appendix 29)
If the allocation information is not detected, the detection process further determines whether it is time to transmit periodic control information;
When it is determined that the transmission process has a timing for transmitting periodic control information, the periodic control information is transmitted by using an uplink control channel resource allocated in advance to transmit the periodic control information. The program according to appendix 26 or appendix 27, wherein the program transmits information.

(Appendix 30)
A program of a base station, wherein the program
Discrimination processing for discriminating resources used for transmission of transmitted information;
A program for executing a reproduction process of reproducing the transmitted information based on a format determined according to the determination result.

(Appendix 31)
The determination process is transmitted using a spreading code to be used for transmission of control information indicating downlink data reception status and an uplink control channel resource associated with an allocation information resource indicating channel allocation of the downlink data. The program according to appendix 30, wherein the resource is determined based on a correlation with a spreading code used in the received information.

(Appendix 32)
The determination process is transmitted using a spreading code to be used for transmission of control information indicating downlink data reception status and an uplink control channel resource associated with an allocation information resource indicating channel allocation of the downlink data. Correlation with the spreading code used in the received information, spreading code to be used for transmission of control information indicating the reception status of downlink data, and uplink assigned in advance for transmission of the control information to be transmitted 32. The program according to appendix 30, wherein the resource is determined based on a correlation with a spreading code used for control information transmitted using a control channel resource.

(Appendix 33)
Uplink control channel resources used when control information indicating downlink data reception status and quality information indicating downlink communication quality are transmitted, and uplink control channel used when the control information is transmitted 33. The program according to any one of appendix 30 to appendix 32, wherein a determination process for determining an allocation information resource indicating allocation of a downlink data channel so as to be orthogonal to the resource is executed.

(Appendix 34)
In the reproduction process, when the determination result indicates that the resource of the uplink control channel associated with the resource of the allocation information is the resource used for the transmitted information, the reception status of the downlink data is Play as a format that includes control information
When the determination result is that the resource of the uplink control channel allocated in advance for the transmission of the quality information is the resource used for the transmitted information, the control indicating the reception status of the downlink data 34. The program according to appendix 31 to appendix 33, wherein the program is reproduced as a format not including information.

(Appendix 35)
A wireless communication method in a wireless communication system, comprising:
When the mobile station detects the allocation information indicating the downlink data channel allocation, the mobile station uses at least the uplink control channel resource associated with the allocation information resource to at least transmit the downlink data indicated by the allocation information. Send information indicating the reception status,
A wireless communication method, wherein a base station reproduces the transmitted information based on a format determined according to a determination result of a resource used for the transmitted information.

  This application claims the priority on the basis of Japanese application Japanese Patent Application No. 2007-209740 for which it applied on August 10, 2007, and takes in those the indications of all here.

10 base station 101 wireless communication control unit 102 PUSCH reproduction unit 103 PUCCH reproduction unit 104 CQI measurement unit 105 control unit 106 scheduler 107 PDCCH generation unit 108 PDSCH generation unit 109 reference signal generation unit 20 mobile station 201 wireless communication unit 202 PDCCH reproduction unit 203 PDSCH playback unit 204 Control unit 205 PUSCH generation unit 206 PUCCH generation unit 207 CAZAC sequence spreading unit 208 CAZAC sequence generation unit 209 DFT
210 Signal selector 211 Subcarrier mapping 212 IFFT
213 Cyclic shift unit 214 Cyclic prefix adding unit 601, 603 Block spreading unit 602 Block spreading code generating unit

Claims (4)

A wireless communication method,
Receiving allocation information indicating channel allocation of downlink data;
Transmitting at least one of the control information indicating the reception status of the downlink data and the quality information indicating the communication quality of the downlink through the uplink control channel;
The radio communication method according to claim 1, wherein the control information and the quality information are transmitted through an uplink control channel associated with a predetermined resource allocated to transmit the control information and the quality information. A first means for receiving allocation information indicating channel allocation of downlink data;
A second means for transmitting at least one of control information indicating a reception status of the downlink data and quality information indicating a downlink communication quality using an uplink control channel;
The second means transmits at least one of the control information and the quality information using an uplink control channel associated with a predetermined resource allocated to transmit the control information and the quality information. A mobile station characterized by: A wireless communication system including a mobile station,
The mobile station
A first means for receiving allocation information indicating channel allocation of downlink data;
A second means for transmitting at least one of control information indicating a reception status of the downlink data and quality information indicating a downlink communication quality using an uplink control channel;
The second means transmits at least one of the control information and the quality information using an uplink control channel associated with a predetermined resource allocated to transmit the control information and the quality information. A wireless communication system. A base station,
Transmitting means for transmitting allocation information indicating channel allocation of downlink data;
Receiving means for receiving at least one of control information indicating a reception status of the downlink data and quality information indicating downlink communication quality from a mobile station via an uplink control channel;
The receiving means receives at least one of the control information and the quality information through an uplink control channel associated with a predetermined resource allocated to transmit the control information and the quality information. A wireless communication method characterized by the above.

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