JP2014027412A - Transmission power control device, base station device, mobile station device, transmission power control method, and computer program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control transmission power according to a type of signals to be transmitted.SOLUTION: A TPC (Transmit Power Control) command generation unit 504 generates a TPC command according to association of a plurality of types of signals to be controlled for their transmission power and a plurality of transmission methods for transmitting information indicating a transmission power control value. A DCI (Downlink Control Information) format generation unit 505 generates DCI including the TPC command input from the TPC command generation unit 504. Then, the DCI including the TPC command is transmitted to a mobile station.

Description

  The present invention relates to a transmission power control apparatus, a base station apparatus, a mobile station apparatus, a transmission power control method, and a computer program.

  Conventionally, LTE (Long Term Evolution) is known as one of the standards studied by 3GPP (Third Generation Partnership Project). LTE is being revised sequentially. In LTE, the specification of a heterogeneous network (HetNet: Heterogeneous Network) is being studied as a method for improving the throughput at the cell edge. HetNet is one in which one or more pico base stations having a narrower coverage are arranged in a communication area of a macro base station having a wide coverage. Furthermore, in LTE, the specification of CoMP (Cooperative Multiple Point) technology that connects a macro base station and a pico base station via a large-capacity and low-delay communication network and performs cooperation between base stations is being studied in HetNet.

  FIG. 8 is a schematic configuration diagram illustrating an example of a mobile radio communication system to which HetNet is applied. In FIG. 8, the mobile radio communication system includes a macro base station (eNB, base station apparatus) 101, a pico base station (eNB, base station apparatus) 111, and a mobile station (UE, mobile station apparatus) 121. Here, the macro base station 101 and the pico base station 111 are connected by a large-capacity and low-delay communication network, and CoMP communication is possible. Further, FIG. 8 shows a communication area 201 of the macro base station 101 and a communication area 211 of the pico base station 111.

  In the example of FIG. 8, one pico base station 111 is provided in the communication area 201 of the macro base station 101, and the communication area 211 of this pico base station 111 is included. Further, in the example of FIG. 8, one mobile station 121 exists near the boundary between the communication area 201 of the macro base station 101 and the communication area 211 of the pico base station 111. The mobile station 121 connects the macro base station 101 as a serving cell, and receives a downlink (direction from the base station toward the mobile station) link signal 301 from the macro base station 101. On the other hand, in the uplink (direction from the mobile station to the base station) link of the mobile station 121, CoMP communication is performed, and the uplink signals 401 and 402 transmitted by the mobile station 121 are transmitted by both the macro base station 101 and the pico base station 111. It is possible to receive.

  In uplink CoMP communication, 3GPP proposes to switch the receiving base station according to the type of uplink signal. For example, in Non-Patent Document 1 and Non-Patent Document 2, it is proposed to switch reception points between an acknowledgment signal (ACK / NACK) and other control signals (for example, CQI (Channel Quality Information)) among uplink control signals. doing.

  In LTE, the following two items (items related to PUCCH sequences and items related to transmission power control) are defined for the uplink control channel (PUCCH: Physical Uplink Control Channel).

(1) PUCCH sequence PUCCH transmits information bits using a pseudo CAZAC (Constant Antidelate and Zero-Autocorrelation) sequence. The pseudo CAZAC sequence is usually generated using the physical cell ID as a seed. However, it is also possible to generate a pseudo CAZAC sequence using an ID (virtual cell ID) specified for each mobile station. Perfect orthogonality between sequences of the same PUCCH is realized by time shift (cyclic shift) of PUCCH sequences. Thereby, a plurality of PUCCH signals are multiplexed in the base station. On the other hand, the design is such that different PUCCH sequences are whitened. Therefore, the reception point (reception base station) of PUCCH corresponds to the ID for generating the PUCCH sequence.

(2) Transmission power control In LTE, the transmission power value P _PUCCH (i) of the uplink control signal is given by equation (1).

However, i is a sub-frame number, P _{CMAX, C} (i) is a maximum transmission power, and P _{0_PUCCH} is a target reception power. PL _c is an uplink path loss value estimated by the mobile station. h () is a correction term corresponding to the number of information bits transmitted on the PUCCH. Δ _{F_PUCCH} (F) is a correction term corresponding to the PUCCH format F. Δ _TxD (F ′) is a correction term when transmission diversity is used. g (i) is a transmission power correction term by closed loop control using a TPC (Transmit Power Control) command.

Note that the PUCCH format is a PUCCH transmission method, and different transmission methods are defined according to information to be transmitted and the number of bits. Further, since PL _c is estimated using a downlink reference signal transmitted from the serving cell, when a base station different from the downlink transmission point is used as the uplink reception point, the path loss due to PL _c is determined. Compensation does not work. In this case, the base station measures the received power of PUCCH, and changes g (i) using a TPC command in order to compensate for a deviation from the received power target value (for example, P _{0_PUCCH} ).

  In LTE, there are two types of TPC command transmission methods. One transmission method of the TPC command is to notify the mobile station of the TPC command using DCI (Downlink Control Information) that notifies downlink data signal allocation (DL-Assignment). Specifically, there are two bits used for the TPC command in the payload of DCI. With 2 bits for the TPC command, it is possible to instruct to increase or decrease the transmission power by “−1, 0, +1, +3” dB.

  DL-Assignment is defined as a DCI format, and in LTE, the DCI format 1A / 1B / 1D / 1 / 2A / 2 / 2B / 2C is applicable.

  Another method of transmitting the TPC command is to notify the mobile station of the TPC command using DCI format 3 / 3A of DCI. The DCI format 3 / 3A does not notify the allocation of the downlink data signal, but notifies the TPC command with 1 bit or 2 bits. Specifically, in the DCI format 3A, it is possible to instruct to increase or decrease the transmission power by “−1, +1” dB by a TPC command notified by 1 bit. In the DCI format 3, it is possible to instruct to increase or decrease the transmission power by “−1, 0, +1, +3” dB by a TPC command notified by 2 bits.

  Further, TPC commands for a plurality of mobile stations can be transmitted by one DCI format 3 / 3A. This mechanism will be explained. First, each mobile station is given one TPC-PUCCH-RNTI and TPC-index by RRC signaling. There are several types of RNTI (Radio Network Temporary ID), and TPC-PUCCH-RNTI is one of them. In the DCI format 3 / 3A, a CRC (Cyclic Redundancy Check) is added and transmitted, but an exclusive logical operation by RNTI (hereinafter, this process is referred to as a mask) is performed on the CRC. Thereby, the mobile station can demodulate only the DCI format 3 / 3A in which the same value as the TPC-PUCCH-RNTI given to the mobile station is used for the CRC mask. The demodulated DCI format 3 / 3A includes TPC commands for a plurality of mobile stations. The mobile station uses the TPC-Index assigned to the mobile station to output a TPC command addressed to the mobile station. You can get it.

  Note that the power control value by the TPC command can be accumulated in the mobile station until the value is reset.

R1-122418 UL CoMP enhancement for PUCCH Nokia Siemens Networks, Nokia, 3GPP RAN WG1, May, 2012 R1-122488 Some Remaining Aspects of PUCCH Enhancement for UL CoMP Alcatel-Lucent Shanghai Bell, Alcatel-Lucent, 3GPP RAN WG1, May, 2012

  However, in the conventional transmission power control method described above, inconvenience occurs when the reception base station is switched according to the type of the uplink signal. Specifically, in Expression (1), the transmission power correction term g (i) by the closed loop control using the TPC command is common regardless of the PUCCH format and the type of signal to be transmitted. It is not possible to realize transmission power control in accordance with.

  The DCI that transmits a TPC command is configured to transmit one type of TPC command, and cannot transmit a plurality of TPC commands according to the PUCCH format or the type of signal to be transmitted.

  The present invention has been made in view of such circumstances, and a transmission power control apparatus, a base station apparatus, a mobile station apparatus, and a transmission power control method capable of performing transmission power control according to the type of signal to be transmitted. It is another object of the present invention to provide a computer program.

  In order to solve the above problem, a transmission power control apparatus according to the present invention includes a plurality of types of signals that are targets for controlling transmission power, and a plurality of transmission methods for transmitting information indicating a transmission power control value. It is characterized by association.

  A base station apparatus according to the present invention, in a base station apparatus that transmits information indicating a transmission power control value to a mobile station apparatus, a plurality of types of signals for which transmission power is controlled, and a transmission power control value A plurality of transmission methods for transmitting the indicated information are associated with each other.

  A mobile station apparatus according to the present invention, in a mobile station apparatus that receives information indicating a transmission power control value from a base station apparatus, a plurality of types of signals for which transmission power is controlled, and information indicating a transmission power control value Is associated with a plurality of transmission methods.

  The transmission power control method according to the present invention includes a step of associating a plurality of types of signals that are targets for controlling transmission power with a plurality of transmission methods that transmit information indicating a transmission power control value. .

  A computer program according to the present invention causes a computer to execute a step of associating a plurality of types of signals that are targets for controlling transmission power with a plurality of transmission methods for transmitting information indicating a transmission power control value. It is a program.

  According to the present invention, information indicating a transmission power control value can be transmitted according to the type of signal to be transmitted. Thereby, the effect that transmission power control can be performed according to the kind of signal to transmit is acquired. For example, when the reception base station is changed according to the type of the uplink control signal, it can contribute to realizing reception power suitable for each base station.

It is a block diagram which shows schematic structure of the base station apparatus (base station) 1 which concerns on one Embodiment of this invention. It is a block diagram which shows schematic structure of the mobile station apparatus (mobile station) 2 which concerns on one Embodiment of this invention. It is a sequence chart which shows the transmission power control method which concerns on Example 1 of this invention. It is a sequence chart which shows the transmission power control method which concerns on Example 1 of this invention. It is a sequence chart which shows the transmission power control method which concerns on Example 1 of this invention. It is a sequence chart which shows the transmission power control method which concerns on Example 3 of this invention. It is a sequence chart which shows the transmission power control method which concerns on Example 3 of this invention. It is a schematic block diagram which shows an example of the mobile radio | wireless communications system to which HetNet is applied.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present embodiment, a radio communication system to which LTE is applied will be described as an example of the radio communication system according to the present invention.

  In this embodiment, a mobile radio communication system to which HetNet and CoMP as exemplified in FIG. 8 is applied is assumed. Moreover, in this embodiment, the uplink which transmits the signal from a mobile station (UE) to a base station (eNB) is assumed. Furthermore, as an access scheme, OFDMA (Orthogonal Frequency Division Multiple Access) or SC-FDMA (Single Carrier-Frequency Division Multiple Access) that performs allocation in the frequency domain is assumed.

  FIG. 1 is a block diagram showing a schematic configuration of a base station apparatus (base station) 1 according to an embodiment of the present invention. The base station 1 shown in FIG. 1 corresponds to the macro base station in FIG. 8, and is connected to the pico base station.

  In FIG. 1, a base station 1 includes a radio reception unit 500, a data demodulation unit 501, a PUCCH reception power measurement unit 502, a reception power difference calculation unit 503, a TPC command generation unit 504, a DCI format generation unit 505, a signal multiplexing unit 506, A wireless transmission unit 507 and a macro base station antenna 508 are provided. A signal received by the pico base station antenna is input to the base station 1 from the pico base station in FIG.

  The uplink signal wirelessly transmitted from the mobile station is received by the macro base station antenna 508 or the pico base station antenna and input to the wireless reception unit 500. Radio receiving section 500 performs down-conversion and FFT (Fast Fourier Transform) processing on the received signal, and outputs the received uplink signal to data demodulating section 501 and PUCCH received power measuring section 502.

  The data demodulation unit demodulates the uplink signal and outputs it to the upper layer.

  PUCCH reception power measurement section 502 measures reception power using a PUCCH signal among uplink signals. This reception power measurement is performed for each type of PUCCH signal or for each of a plurality of types of PUCCH signals.

PUCCH has a plurality of formats (A-1 to 5) as shown below, and the following information is transmitted in each PUCCH format.
(A-1) Format 1: Scheduling request (SR)
(A-2) Dynamic Format 1a / 1b: ACK / NACK in which resource allocation changes dynamically
(A-3) Semi-static Format 1a / 1b: ACK / NACK in which resource allocation is specified by RRC signaling and becomes semi-fixed
(A-4) Format 2: CQI
(A-5) Format 3: ACK / NACK of 5 bits or more

  In the present embodiment, the PUCCH received power measuring unit 502 is configured by a plurality of blocks corresponding to a group of PUCCH format. For example, the semi-static Format 1a / 1b (A-3), the dynamic Format 1a / 1b (A-2), and the Format 3 (A-5) are grouped into one group (PUCCH format group G1), and the other formats (A-1, Let A-4) be one group (PUCCH format group G2). In this case, since two PUCCH format groups G1 and G2 are generated, the PUCCH reception power measuring unit 502 is configured by two blocks. Then, one block of the PUCCH reception power measuring unit 502 measures the reception power of the PUCCH format belonging to the PUCCH format group G1, and the other block measures the reception power of the PUCCH format belonging to the PUCCH format group G2.

  Assume that each PUCCH format group has a different receiving base station. For example, the PUCCH format group G1 is received by the macro base station, and the mobile station generates the PUCCH sequence using the virtual cell ID (V1) corresponding to the macro base station. On the other hand, the PUCCH format group G2 is received by the pico base station, and the mobile station generates a PUCCH sequence with a virtual cell ID (V2) corresponding to the pico base station. When the receiving base station matches the serving cell, the physical cell ID of the serving cell may be used without using the virtual cell ID.

  The received power measurement value of each PUCCH format group measured by PUCCH received power measuring section 502 is output to received power difference calculating section 503 provided corresponding to each PUCCH format group.

The reception power difference calculation unit 503 calculates a difference value Xn between a desired reception power value at the reception base station and the reception power measurement value input from the PUCCH reception power measurement unit 502. Here, n is an index indicating a PUCCH format group. The desired received power value at the receiving base station is, for example, _{PO_PUCCH} defined in Equation (1). The difference value Xn of each PUCCH format group calculated by the received power difference calculation unit 503 is output to the TPC command generation unit 504 provided corresponding to each PUCCH format group.

  The TPC command generation unit 504 generates a TPC command for each PUCCH format group based on the difference value Xn of each PUCCH format group. The TPC command generated by the TPC command generation unit 504 is output to the DCI format generation unit 505. The DCI format generation unit 505 generates DCI including the TPC command input from the TPC command generation unit 504.

  The output of the DCI format generator 505 is input to the signal multiplexer 506 and multiplexed with a signal such as downlink transmission data. The multiplexed signal is input to the wireless transmission unit 507 and wirelessly transmitted from the macro base station antenna 508 as an OFDM signal.

  FIG. 2 is a block diagram showing a schematic configuration of the mobile station apparatus (mobile station) 2 according to the embodiment of the present invention. In FIG. 2, the mobile station 2 includes a radio reception unit 600, a DCI reception unit 601, a data demodulation unit 602, a TPC command acquisition unit 603, a transmission power adjustment unit 604, a transmission power application unit 605, a PUCCH sequence generation unit 606, and radio transmission. A portion 607 and an antenna 608.

  A downlink signal wirelessly transmitted from the macro base station antenna 508 is received by the antenna 608 of the mobile station 2. A signal received by the antenna 608 is input to the wireless reception unit 600. Radio receiving section 600 performs down-conversion and FFT (Fast Fourier Transform) processing on the received signal, and outputs the received downlink signal to DCI receiving section 601 and data demodulating section 602.

  The data demodulator 602 demodulates the downlink signal and outputs it to the upper layer.

  The DCI receiving unit 601 acquires DCI including a TPC command from DCI assigned to the own station from the input downlink signal. The DCI reception unit 601 outputs the acquired DCI to the TPC command acquisition unit 603.

  The TPC command acquisition unit 603 acquires a TPC command from the input DCI. The TPC command acquisition unit 603 outputs transmission power control information to the transmission power adjustment unit 604 for each PUCCH format group based on the acquired TPC command.

  The transmission power adjustment unit 604 includes blocks corresponding to each PUCCH format group. Based on the transmission power control information for each PUCCH format group input from TPC command acquisition section 603, transmission power adjustment section 604 determines a transmission power value for each PUCCH format. The transmission power value for each PUCCH format is output to transmission power application section 605.

  Here, a method for determining the transmission power value for each PUCCH format will be described. The transmission power control information input from the TPC command acquisition unit 603 to the transmission power adjustment unit 604 includes PUCCH format information and a transmission power control value. The PUCCH format information is information indicating the PUCCH format. The transmission power adjustment unit 604 determines the transmission power value for each PUCCH format based on the PUCCH format information and the transmission power control value.

  The transmission power adjustment unit 604 calculates g (F ″, i) shown in Expression (2) for each PUCCH format. In Expression (2), the current transmission power control value is calculated from the past transmission power control value. It is added to the cumulative value.

Here, i is a subframe number. g (F ″, i) is a transmission power correction term corresponding to the PUCCH format F ″. δ _PUCCH (F ″, i) is a transmission power control value for the PUCCH format F belonging to the PUCCH format group of the TPC command by the TPC command of the i-th subframe.

The transmission power adjustment unit 604 applies g (F ″, i) calculated by Expression (2) to Expression (3) to calculate the transmission power value P _PUCCH (i) of PUCCH format F. Expression (3) ) Changes the transmission power correction term “g (i)” by the closed loop control using the TPC command to “g (F”, i) ”corresponding to the PUCCH format F” with respect to the equation (1). doing.

  Transmission power application section 605 applies the transmission power value for each PUCCH format input from transmission power adjustment section 604 to uplink transmission data. PUCCH sequence generation unit 606 generates a PUCCH sequence for the uplink transmission data output from transmission power application unit 605. The generated PUCCH sequence is wirelessly transmitted from the antenna 608 after processing such as conversion to a time signal and up-conversion is performed by the wireless transmission unit 607.

  Next, the transmission power control method according to the present embodiment will be described with reference to examples.

  In the first embodiment, two transmission methods are used as a method for transmitting a TPC command from the base station 1 to the mobile station 2. The first transmission method uses DCI for notifying downlink data signal allocation (DL-Assignment). The second transmission method uses DCI format 3 / 3A. The DCI format 3 / 3A does not notify allocation of downlink data signals.

  In the first transmission method, a TPC command of one PUCCH format group is transmitted by DCI notifying DL-Assignment (hereinafter referred to as DL-Assignment_DCI). Since DL-Assignment_DCI has 2 bits used for the TPC command, the transmission power related to the PUCCH format belonging to one PUCCH format group is set to “−1, 0, +1, +3” by 2 bits for the TPC command. An instruction to increase or decrease dB can be given.

  Based on the DL-Assignment_DCI TPC command, the mobile station 2 determines the transmission power control value of the PUCCH format group corresponding to the TPC command. For example, the transmission power control value corresponding to the bit value of the TPC command is determined from the transmission power control values “−1, 0, +1, +3” dB represented by 2 bits of the TPC command. The mobile station 2 generates transmission power control information having the determined transmission power control value and PUCCH format information indicating the PUCCH format belonging to the PUCCH format group.

  In the second transmission method, TPC commands related to a plurality of PUCCH format groups are transmitted using DCI format 3 / 3A. In the first embodiment, a DCI format 3 / 3A corresponding to each PUCCH format group is configured by providing a value used for a CRC mask related to the DCI format 3 / 3A for each PUCCH format group. For this reason, each mobile station 2 has as many TPC-PUCCH-RNTIs as the number of PUCCH format groups used for the CRC mask of the DCI format 3 / 3A corresponding to each PUCCH format group as each TPC-PUCCH-RNTI. Is given. Accordingly, the mobile station 2 can demodulate only the DCI format 3 / 3A in which any one of the TPC-PUCCH-RNTIs given to the mobile station 2 is used for the CRC mask. The mobile station 2 uses the DCI format 3 / 3A TPC command that has been demodulated for the PUCCH format group corresponding to the TPC-PUCCH-RNTI used for the demodulation.

  Since the DCI format 3A notifies the TPC command with 1 bit, the transmission related to the PUCCH format belonging to the PUCCH format group corresponding to the TPC-PUCCH-RNTI used for demodulation of the DCI format 3A is transmitted by 1 bit for the TPC command. An instruction to increase or decrease the power by “−1, +1” dB can be given. Further, since the DCI format 3 notifies the TPC command with 2 bits, the 1 bit for this TPC command is used to indicate the PUCCH format belonging to the PUCCH format group corresponding to the TPC-PUCCH-RNTI used for the demodulation of the DCI format 3. It can be instructed to increase or decrease the transmission power of “−1, 0, +1, +3” dB.

  Based on the DCI format 3 / 3A TPC command, the mobile station 2 determines the transmission power control value of the PUCCH format group corresponding to the TPC command. For example, in the case of the DCI format 3A, the transmission power control value corresponding to the bit value of the TPC command is determined from the transmission power control values “−1, +1” dB represented by 1 bit of the TPC command. The mobile station 2 generates transmission power control information having the determined transmission power control value and PUCCH format information indicating the PUCCH format belonging to the PUCCH format group.

  Next, the transmission power control method according to the first embodiment will be described with reference to FIG. 3, FIG. 4, and FIG. 3, 4 and 5 are sequence charts showing the transmission power control method according to the first embodiment of the present invention.

  Here, for convenience of explanation, the number of PUCCH format groups is two. One PUCCH format group G1 includes semi-static Format 1a / 1b (A-3), dynamic Format 1a / 1b (A-2), and Format 3 (A-5). Thereby, PUCCH format group G1 respond | corresponds only to ACK / NACK. Another PUCCH format group G2 is composed of formats (A-1, A-4) that do not belong to the PUCCH format group G1. Thereby, the PUCCH format group G2 corresponds to SR and CQI.

  3, 4, and 5, the base station A is the base station 1 according to the present embodiment and corresponds to the macro base station of FIG. 8, and the base station B corresponds to the pico base station of FIG. 8. The mobile station is the mobile station 2 according to the present embodiment.

  In the mobile station, a PUCCH Format2 resource used for CQI transmission, a virtual cell ID (V1) used for ACK / NACK transmission, a virtual cell ID (V2) used for CQI transmission, and TPC-PUCCH-RNTI (1) , TPC-PUCCH-RNTI (2), and TPC-Index are set. Also, in the mobile station, it is set in advance that TPC-PUCCH-RNTI (1) corresponds to PUCCH format group G1 and TPC-PUCCH-RNTI (2) corresponds to PUCCH format group G2. Also, in the mobile station, it is set in advance that DL-Assignment_DCI corresponds to PUCCH format group G1. These settings may be performed from the base station A or may be performed from the base station A through the base station B. Moreover, those settings may be set by a single process, or may be set by a plurality of signaling.

First, with reference to FIG. 3, the transmission power control method of PUCCH format group G1 by TPC command transmission using the first transmission method will be described.
(Step S1) The base station A transmits DL-Assignment (DL-Assignment_DCI) to the mobile station.

(Step S2) The base station A transmits a downlink data (DL data) signal to the mobile station according to the DL-Assignment in step S1.

(Step S3) The mobile station demodulates the DL data signal received in step S2 according to the DL-Assignment received in step S1.

(Step S4) The mobile station transmits ACK / NACK to the base station A according to the result of demodulation in step S2.

(Step S5) The base station A calculates the difference (difference value X1) between the desired received power value (target received power) and the received power measurement value (ACK / NACK received power) of ACK / NACK received from the mobile station. taking measurement.

(Step S6) The base station A generates a TPC command for the PUCCH format group G1 based on the difference value X1 measured in step S5. And the base station A transmits DL-Assignment_DCI including the TPC command of the PUCCH format group G1 to the mobile station.

(Step S7) The base station A transmits a DL data signal to the mobile station according to the DL-Assignment in step S6.

(Step S8) The mobile station demodulates the DL data signal received in step S7 according to the DL-Assignment received in step S6.

(Step S9) The mobile station acquires a TPC command from the DL-Assignment_DCI received in step S6. And a mobile station adjusts the transmission power of the PUCCH format which belongs to PUCCH format group G1 based on this acquired TPC command. Thereby, the transmission power of ACK / NACK is adjusted.

(Step S10) The mobile station transmits ACK / NACK to the base station A according to the result of demodulation in step S8. The transmission power of this ACK / NACK reflects the adjustment result in step S9.

  Next, a transmission power control method for PUCCH format group G1 by TPC command transmission using the second transmission method will be described with reference to FIG. In FIG. 4, steps S1 to S5 are the same as those in FIG. However, in the example of FIG. 4, there is no DL data signal to be transmitted to the mobile station at the transmission timing of the TPC command as a result of step S5. For this reason, since the first transmission method cannot be used, the base station A transmits the TPC command using the second transmission method.

(Step S20) The base station A generates a TPC command for the PUCCH format group G1 based on the difference value X1 measured in step S5. Then, the base station A transmits a TPC command of the PUCCH format group G1 to the mobile station using the DCI format 3 / 3A. In the DCI format 3 / 3A, CRC masking is performed using TPC-PUCCH-RNTI (1) corresponding to the PUCCH format group G1.

(Step S21) The mobile station acquires a TPC command from the DCI format 3 / 3A received in step S20 using TPC-PUCCH-RNTI (1). And a mobile station adjusts the transmission power of the PUCCH format which belongs to PUCCH format group G1 based on this acquired TPC command. Thereby, the transmission power of ACK / NACK is adjusted.

  Next, a transmission power control method for the PUCCH format group G2 by TPC command transmission using the second transmission method will be described with reference to FIG.

(Step S30) The mobile station transmits CQI to the base station B using the PUCCH Format2.

(Step S31) The CQI received by the antenna of the base station B is transmitted to the base station A.

(Step S32) The base station A measures a difference (difference value X2) between a desired received power value (target received power) and a received power measurement value (CQI received power) of CQI transmitted from the base station B. .

(Step S33) The base station A generates a TPC command for the PUCCH format group G2 based on the difference value X2 measured in step S32. Then, the base station A transmits a TPC command of the PUCCH format group G2 to the mobile station using the DCI format 3 / 3A. In this DCI format 3 / 3A, CRC masking is performed using TPC-PUCCH-RNTI (2) corresponding to PUCCH format group G2.

(Step S34) The mobile station acquires a TPC command from the DCI format 3 / 3A received in step S20 using TPC-PUCCH-RNTI (2). And a mobile station adjusts the transmission power of the PUCCH format which belongs to PUCCH format group G2 based on this acquired TPC command. Thereby, the transmission power of CQI is adjusted.

  According to the first embodiment, the TPC command transmission method (first transmission method) by DL-Assignment_DCI is applied to only one PUCCH format group, and the TPC command by DCI format 3 / 3A is applied to the other PUCCH format groups. The transmission method (second transmission method) is applied. Thereby, different TPC commands can be transmitted to a plurality of PUCCH format groups. As a result, transmission power control can be performed according to the type of PUCCH format.

  Moreover, since the application range of the TPC command by DL-Assignment_DCI is limited to only one PUCCH format group, it is not necessary to change the configuration of DL-Assignment_DCI.

  In the second embodiment, only a TPC command transmission method (second transmission method) using the DCI format 3 / 3A is used as a method for transmitting a TPC command from the base station 1 to the mobile station 2. The second transmission method is the same as that in the first embodiment.

  Specifically, for example, similarly to the example of FIGS. 4 and 5 described above, the CRC of the DCI format 3 / 3A is performed using the TPC-PUCCH-RNTI (1) for the PUCCH format group G1, For the PUCCH format group G2, a CRC of DCI format 3 / 3A is masked using TPC-PUCCH-RNTI (2).

  According to the second embodiment, different TPC commands can be transmitted to a plurality of PUCCH format groups only by a TPC command transmission method (second transmission method) in DCI format 3 / 3A. As a result, transmission power control can be performed according to the type of PUCCH format.

  In the third embodiment, only a TPC command transmission method (third transmission method) using the DCI format 3 / 3A is used as a method for transmitting a TPC command from the base station 1 to the mobile station 2. In this third transmission method, unlike the second transmission method in which TPC-PUCCH-RNTI is extended, the TPC-index is extended, whereby TPCs related to a plurality of PUCCH format groups using DCI format 3 / 3A. Send a command.

  Each mobile station 2 is provided with TPC-indexes corresponding to the number of PUCCH format groups. As a result, the mobile station 2 uses the TPC-index that matches one of the TPC-indexes given to itself to send a TPC command addressed to itself from the demodulated DCI format 3 / 3A. get. Then, the mobile station 2 uses the acquired TPC command for the PUCCH format group corresponding to the TPC-index used for the acquisition.

  Next, a transmission power control method according to the third embodiment will be described with reference to FIGS. 6 and 7. 6 and 7 are sequence charts showing a transmission power control method according to the third embodiment of the present invention. In FIG. 6, the same parts as those in each step of FIG. In FIG. 7, the same parts as those in FIG. 5 are denoted by the same reference numerals.

  Here, as in the first embodiment, two PUCCH format groups G1 and G2 are provided. In the mobile station, TPC-PUCCH-RNTI, TPC-Index (1), and TPC-Index (2) are set in advance. Also, in the mobile station, it is set in advance that TPC-Index (1) corresponds to PUCCH format group G1 and TPC-Index (2) corresponds to PUCCH format group G2.

  First, the transmission power control method for the PUCCH format group G1 by TPC command transmission using the third transmission method will be described with reference to FIG. In FIG. 6, steps S1 to S5 are the same as those in FIG.

(Step S40) The base station A generates a TPC command for the PUCCH format group G1 based on the difference value X1 measured in step S5. Then, the base station A transmits a TPC command of the PUCCH format group G1 to the mobile station using the DCI format 3 / 3A. The DCI format 3 / 3A is assigned TPC-Index (1) corresponding to the PUCCH format group G1.

(Step S41) The mobile station acquires a TPC command from the DCI format 3 / 3A received in step S40 by using TPC-Index (1). And a mobile station adjusts the transmission power of the PUCCH format which belongs to PUCCH format group G1 based on this acquired TPC command. Thereby, the transmission power of ACK / NACK is adjusted.

  Next, a transmission power control method for the PUCCH format group G2 by TPC command transmission using the third transmission method will be described with reference to FIG. In FIG. 7, steps S30 to S32 are the same as those in FIG.

(Step S50) The base station A generates a TPC command for the PUCCH format group G2 based on the difference value X2 measured in step S32. Then, the base station A transmits a TPC command of the PUCCH format group G2 to the mobile station using the DCI format 3 / 3A. The DCI format 3 / 3A is assigned TPC-Index (2) corresponding to the PUCCH format group G2.

(Step S51) The mobile station acquires a TPC command from the DCI format 3 / 3A received in step S50 using TPC-Index (2). And a mobile station adjusts the transmission power of the PUCCH format which belongs to PUCCH format group G2 based on this acquired TPC command. Thereby, the transmission power of CQI is adjusted.

  According to the third embodiment, different TPC commands can be transmitted to a plurality of PUCCH format groups only by the TPC command transmission method (third transmission method) in the DCI format 3 / 3A. As a result, transmission power control can be performed according to the type of PUCCH format.

  As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the specific structure is not restricted to this embodiment, The design change etc. of the range which does not deviate from the summary of this invention are included.

  For example, the first, second, and third transmission methods described above can be arbitrarily combined. In addition to the combination of the above-described embodiments, the first transmission method and the third transmission method may be combined, or the second transmission method and the third transmission method may be combined, or the first transmission method may be combined. The transmission method, the second transmission method, and the third transmission method may be combined.

  In the above-described embodiment, DL-Assignment_DCI is used only for one PUCCH format group. However, if the number of bits for TPC commands included in DL-Assignment_DCI can be increased, the DL-Assignment_DCI can be used for multiple PUCCH format groups. It is also possible to send a TPC command.

  In the above-described embodiment, the present invention is applied to the macro base station in FIG. 8, but the present invention is also applicable to a pico base station. In addition, the present invention can also be applied to a base station that integrates a plurality of macro base stations and pico base stations in a CoMP environment, or a baseband processing device equivalent thereto.

  In each of the above-described embodiments, two PUCCH format groups are described. However, the present invention can be similarly applied to a case where there are three or more PUCCH format groups, that is, a case where there are three or more reception points.

  Moreover, the PUCCH format which belongs to each PUCCH format group is arbitrary, and can respond to the combination of various PUCCH formats. Further, the configuration of the PUCCH format group may be fixed or may be dynamically changed. For example, the configuration of the PUCCH format group may be notified from the base station to the mobile station.

  Also, the PUCCH format group can be matched with the virtual cell ID applied for each PUCCH format. Thereby, signaling from the base station to the mobile station can be reduced.

  Moreover, although the PUCCH format group was comprised in embodiment mentioned above, a PUCCH format group is not essential. A plurality of types of signals for which transmission power is to be controlled may be associated with a plurality of transmission methods for transmitting information indicating transmission power control values. For example, a TPC command transmission method may be associated with each type of signal to be transmitted from among a plurality of TPC command transmission methods.

  The present invention is not limited to LTE and can be applied to various wireless communication systems. Further, any wireless communication system that can have a plurality of transmission methods for transmitting information indicating the transmission power control value may be used, and the transmission method may have any configuration. The present invention is also applicable to controlling the transmission power of an arbitrary signal (which may be an uplink signal or a downlink signal) transmitted and received between the base station device and the mobile station device. Further, the present invention is not limited to a base station device or a mobile station device, and can also be applied to control of transmission power of signals transmitted / received between various wireless communication devices.

Further, a program for realizing each step shown in FIG. 4, FIG. 5, FIG. 6 or FIG. 7 is recorded on a computer-readable recording medium, and the program recorded on this recording medium is read into a computer system, The transmission power control process may be performed by executing. Here, the “computer system” may include an OS and hardware such as peripheral devices.
“Computer-readable recording medium” refers to a flexible disk, a magneto-optical disk, a ROM, a writable nonvolatile memory such as a flash memory, a portable medium such as a DVD (Digital Versatile Disk), and a built-in computer system. A storage device such as a hard disk.

Further, the “computer-readable recording medium” means a volatile memory (for example, DRAM (Dynamic DRAM) in a computer system that becomes a server or a client when a program is transmitted through a network such as the Internet or a communication line such as a telephone line. Random Access Memory)), etc., which hold programs for a certain period of time.
The program may be transmitted from a computer system storing the program in a storage device or the like to another computer system via a transmission medium or by a transmission wave in the transmission medium. Here, the “transmission medium” for transmitting the program refers to a medium having a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line.
The program may be for realizing a part of the functions described above. Furthermore, what can implement | achieve the function mentioned above in combination with the program already recorded on the computer system, and what is called a difference file (difference program) may be sufficient.

DESCRIPTION OF SYMBOLS 1 ... Base station apparatus (base station), 2 ... Mobile station apparatus (mobile station), 500 ... Radio reception part, 501 ... Data demodulation part, 502 ... PUCCH reception power measurement part, 503 ... Reception power difference calculation part, 504 ... TPC command generation unit, 505... DCI format generation unit, 506... Signal multiplexing unit, 507... Radio transmission unit, 508... Macro base station antenna, 600. ... TPC command acquisition unit, 604 ... transmission power adjustment unit, 605 ... transmission power application unit, 606 ... PUCCH sequence generation unit, 607 ... radio transmission unit, 608 ... antenna

Claims (5)

  A transmission power control apparatus characterized by associating a plurality of types of signals for which transmission power is controlled with a plurality of transmission methods for transmitting information indicating a transmission power control value. In the base station device that transmits information indicating the transmission power control value to the mobile station device,
A base station apparatus characterized by associating a plurality of types of signals for which transmission power is controlled with a plurality of transmission methods for transmitting information indicating a transmission power control value. In the mobile station device that receives information indicating the transmission power control value from the base station device,
A mobile station apparatus characterized by associating a plurality of types of signals for which transmission power is controlled with a plurality of transmission methods for transmitting information indicating a transmission power control value.   A transmission power control method comprising a step of associating a plurality of types of signals that are targets for controlling transmission power with a plurality of transmission methods for transmitting information indicating a transmission power control value. On the computer,
A computer program for executing a step of associating a plurality of types of signals for which transmission power is controlled with a plurality of transmission methods for transmitting information indicating a transmission power control value.

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