WO2012108685A2 - Method and apparatus for allocating an ack/nack resource, and method for transmitting an ack/nack signal using same - Google Patents

Abstract

The present invention relates to a method for allocating a transmission resource, and to a method for transmitting a HARQ response signal using same in a time division duplex (TDD) system using a single carrier. According to the present invention, a method for allocating a transmission resource involves allocating, as a transmission resource to be used in the transmission of an uplink control channel, a transmission resource indicated by a resource indicator on a resourcemapping table consisting of resources of an uplink control channel format to which discrete fourier transform-spreading-orthogonal frequency-division multiplexing (DFT-S-OFDM) is applied. The resource indicator transmits information to a terminal using a power control field transmitted on a control channel of a downlink subframe. The resource-mapping table may be constituted such that the same number of transmission resources as the number of the transmission antennas of the terminal may be allocated by the resource indicator.

Description

ACC / NAC resource allocation method and apparatus and ACC / NAC signal transmission method using same

The present invention relates to wireless communication, and more particularly, to a wireless communication system supporting multiple carriers.

Wireless communication systems generally use one bandwidth for data transmission. For example, second generation wireless communication systems use a bandwidth of 200 KHz-1.25 MHz, and third generation wireless communication systems use a bandwidth of 5 MHz-10 MHz. In order to support increasing transmission capacity, the recent Long Term Evolution (LTE) or IEEE 802.16m of the 3rd Generation Partnership Project (3GPP) continues to expand its bandwidth to 20 MHz or more. Increasing bandwidth is essential to increase transmission capacity, but frequency allocation of large bandwidths is not easy except in some regions of the world.

An object of the present invention is to provide a method for effectively allocating a transmission resource for transmitting an ACK / NACK signal for a single carrier in a single carrier (TDD) single carrier system.

An object of the present invention is to provide a method for effectively allocating transmission resources when a UE transmits a HARQ ACK / NACK response by applying SORTD in a single carrier (TDD) single carrier system. do.

An object of the present invention is to provide a preliminary method for transmitting a HARQ signal by a terminal when HARQ transmission is difficult to be performed in a manner set between the terminal and the base station.

The present invention relates to a resource allocation method of a base station in a time division duplex (TDD) system using a single carrier, and according to this, uplink control to which Discrete Fourier Transform-Spreading-Orthogonal Frequency-Division Multiplexing (DFT-S-OFDM) is applied. On the resource mapping table composed of the resources of the channel format, a transmission resource indicated by the resource indicator is allocated as a transmission resource to be used for transmission of the uplink control channel, and the resource indicator identifies a power control field transmitted on the control channel of the downlink subframe. The resource mapping table may be configured to transmit the same number of transmission resources as the number of transmission antennas of the terminal by the resource indicator.

The present invention also relates to a method for transmitting a HARQ response signal of a terminal in a TDD (Time Division Duplex) system using a single carrier, and accordingly, according to Discrete Fourier Transform-Spreading-Orthogonal Frequency-Division Multiplexing ) Acquires a transmission resource indicated by the resource indicator as a transmission resource to be used for transmission of the uplink control channel on a resource mapping table configured of a resource of an uplink control channel format to which the base station is applied, and uses the obtained transmission resource to transmit a HARQ response signal to the base station. The resource indicator is transmitted from the base station using a power control field transmitted on the control channel of the downlink subframe, and the resource mapping table allocates the same number of transmission resources as the number of transmit antennas of the terminal by the resource indicator. It may be configured to.

The present invention relates to a method of transmitting a HARQ signal of a terminal, the method comprising: determining whether a resource allocation indicator for allocating a transmission resource to a downlink subframe associated with an uplink subframe to transmit the HARQ signal is received; If it is determined that the resource allocation indicator has not been received, when dynamic scheduling is applied, resources are allocated based on the control channel element index on the control channel in the received downlink subframe, and static scheduling is applied. If so, the step of allocating resources indicated by the resource allocation indicator transmitted on the downlink control channel with the static scheduling enabled and transmitting the HARQ signal using the allocated resources.

At this time, when the determination result, when receiving a resource allocation indicator for allocating the transmission resources to the downlink subframe associated with the uplink subframe to transmit the HARQ signal, the resource allocation indicator may be allocated to transmit the HARQ signal. .

The step of allocating a resource may include determining whether to transmit a HARQ signal by applying SORTD even if a resource allocation indicator for allocating a transmission resource is received in a downlink subframe associated with an uplink subframe to which the HARQ signal is to be transmitted. In addition, if it is determined that the SORTD is applied, a plurality of transmission resources may be allocated, and when using a single antenna that does not apply the SORTD, one transmission resource may be allocated.

At this time, whether to apply the SORTD is pre-set between the terminal and the base station, or information for determining whether to apply the SORTD may be sheared from the base station to the terminal through higher layer signaling.

When dynamic scheduling is applied, when SORTD is applied, two resources are allocated based on control channel indices obtained from two control channel elements on a control channel in a received downlink subframe, and when static scheduling is applied. Two resources indicated by the resource allocation indicator transmitted on the downlink control channel with the static scheduling enabled may be allocated.

Further, in the step of allocating a resource, when a resource allocation indicator for allocating a transmission resource to a downlink subframe associated with an uplink subframe to transmit the HARQ signal is received, the HARQ signal is transmitted in the same transmission method as that of transmitting a HARQ signal. In the HARQ signal transmission step, when the resource allocation indicator for allocating a transmission resource to a downlink subframe associated with an uplink subframe to transmit the HARQ signal is received, the HARQ signal may be allocated. The HARQ signal may be transmitted in the same transmission method as that of transmitting.

If a resource allocation indicator for allocating a transmission resource to a downlink subframe associated with an uplink subframe to transmit the HARQ signal is not received, the resource allocated by the UE may be PUCCH format 1a or PUCCH format 1b.

The method may further include performing time domain bundling and / or spatial bundling when the HARQ signal to be transmitted exceeds a size that can be transmitted through the allocated resource.

In addition, when a plurality of downlink subframes is received, the method may further include performing time domain bundling and / or spatial bundling.

Meanwhile, the present invention provides a method for allocating an HARQ resource of a base station, when the terminal does not receive a resource allocation indicator for allocating a transmission resource to a downlink subframe associated with an uplink subframe to transmit the HARQ signal, the terminal receives the HARQ signal. Setting a method of allocating a transmission resource to be used for transmission and, according to the set method, implicitly allocating transmission resources when dynamic scheduling is applied or explicitly allocating transmission resources when static scheduling is applied. The resource to be explicitly allocated may be allocated by a resource allocation indicator transmitted by utilizing a bit to be used in a transmission power control command transmitted on a control channel for activating static scheduling.

In this case, the transmission resources may be allocated the required number according to the HARQ transmission scheme of the terminal, the HARQ transmission scheme of the terminal, resource allocation indicator for allocating the transmission resources to the downlink subframe associated with the uplink subframe to transmit the HARQ signal It may be the same as the transmission method when the terminal receives.

According to the present invention, in a single carrier (TDD) single carrier system, a transmission resource for transmitting an ACK / NACK signal for a single carrier can be effectively allocated.

According to the present invention, in a single carrier system using a time division duplex (TDD) system, radio resources can be effectively utilized by dedicating resources allocated to control signals that are redundantly transmitted.

According to the present invention, in a single carrier system using a time division duplex (TDD) scheme, when a terminal transmits a HARQ ACK / NACK response by applying SORTD, a transmission resource can be effectively allocated.

According to the present invention, when HARQ transmission is difficult to be performed in a manner set between the terminal and the base station, the terminal may transmit the HARQ signal to the base station through a preliminary method.

FIG. 1 illustrates uplink-downlink configuration 5 in a TDD system using a single carrier.

FIG. 2 illustrates uplink-downlink configuration 1 in a TDD system using a single carrier.

FIG. 3 schematically illustrates an example of specifying a downlink subframe for transmitting ARI in uplink-downlink configuration 2 in a TDD system using a single carrier.

FIG. 4 schematically illustrates an example of configuring an ARI window for uplink-downlink configuration 0 in a TDD system using a single carrier.

FIG. 5 schematically illustrates an example of configuring an ARI window for uplink-downlink configuration 1 in a TDD system using a single carrier.

FIG. 6 is a diagram schematically illustrating an example of performing time domain bundling to transmit an HARQ ACK / NACK signal using PUCCH format 1b.

FIG. 7 is a diagram schematically illustrating an example of performing spatial bundling and time domain bundling to transmit an HARQ ACK / NACK signal using PUCCH format 1a.

8 is a diagram schematically illustrating an example of a normal mode when an SPS is activated.

FIG. 9 is a diagram schematically illustrating an example in which a contrast mode is applied by only transmitting major carriers in which an SPS is transmitted in one downlink subframe.

FIG. 10 is a diagram schematically illustrating a contrast mode applied when there is a subframe and / or a component carrier on which dynamic scheduling is performed.

11 is a diagram schematically illustrating an example in which a resource allocation scheme may be maintained.

12 is a flowchart schematically illustrating an operation of a base station in a TDD system using a single carrier to which the present invention is applied.

13 is a flowchart schematically illustrating an operation of a terminal in a TDD system using a single carrier, to which the present invention is applied.

14 is a diagram schematically illustrating an operation of a terminal when a contrast mode is applied according to the present invention.

15 is a block diagram schematically illustrating an example of a configuration of a base station and a terminal in a system to which the present invention is applied.

Hereinafter, some embodiments will be described in detail with reference to the accompanying drawings. In describing the embodiments of the present specification, when it is determined that a detailed description of a related well-known configuration or function may obscure the gist of the present specification, the detailed description thereof will be omitted.

There is no limitation on the multiple access scheme applied to the wireless communication system. Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier-FDMA (SC-FDMA), OFDM-FDMA, OFDM-TDMA For example, various multiple access schemes such as OFDM-CDMA may be used.

Carrier Aggregation (hereinafter, referred to as CA) supports a plurality of carriers, and is also referred to as spectrum aggregation or bandwidth aggregation.

The number of carriers aggregated between the downlink and the uplink may be set differently, and the size (ie, bandwidth) of the component carriers may be different. Each component carrier may have a control channel such as a PDCCH, which will be described later, and may or may not be adjacent to each other. The terminal may support one or more carriers according to performance.

The CC may be divided into a Primary Component Carrier (PCC) and a Secondary Component Carrier (SCC) according to activation. The major carriers are always active carriers, and the subcarrier carriers are carriers that are activated / deactivated according to specific conditions. Activation refers to the transmission or reception of traffic data being made or in a ready state.

Hereinafter, the CA environment refers to a system supporting multi-component carriers (carrier aggregation).

In carrier aggregation, a physical downlink control channel (PDCCH) may transmit allocation information for resources of other carriers as well as resource allocation in a carrier to which the corresponding PDCCH belongs.

The message transmitted on the PDCCH includes a transmission power control (TPC) for controlling uplink transmission power.

In a carrier aggregation environment, the PDCCH of each carrier may transmit a TPC command for a physical uplink control channel (PUCCH) of the same uplink component carrier. When there are a plurality of TPCs for one PUCCH due to a plurality of downlink grant transmissions, bits allocated to overlapping TPC fields may be used for transmission of other control information, for example, ACK / NACK resource allocation information.

The terminal receiving the downlink data from the base station transmits an ACK (ACKnowledgement) / NACK (Not-ACKnowledgement) response to the base station after a predetermined time elapses or at a certain timing. The downlink data may be transmitted on the PDSCH indicated by the PDCCH. A hybrid automatic repeat request (HARQ) signal for downlink data may be transmitted on the PUCCH. The HARQ ACK / NACK signal becomes ACK information when the downlink data is successfully decoded, and becomes NACK information when the decoding of the downlink data fails. When the NACK information is received, the base station may retransmit the downlink data up to a maximum number of retransmissions.

On the other hand, in a multi-antenna system, SORTD (Spatial Orthogonal Resource Transmit Diversity) transmitted through different antennas and using different transmission resources may be applied. SORTD may also be applied to each PUCCH format.

Resource Index that is a resource for transmission of PUCCH format 1 / 1a / 1b n ⁽¹⁾ _PUCCH is not only the location of the physical resource block to which the HARQ ACK / NACK signal is transmitted, but also the CS amount α (n _s of the base sequence). , l) and orthogonal sequence index n _OC (n _s ). And, the resource index n ⁽¹⁾ _PUCCH for the HARQ ACK / NACK signal can be obtained as shown in Table 1 below. The resource index n ⁽¹⁾ _PUCCH is a parameter for determining the physical RB index n _PRB , the CS amount α (n _s , l) of the base sequence, and the orthogonal sequence index n _OC (n _s ).

TABLE 1

That is, according to Table 1, the HARQ ACK / NACK signal for the PDSCH transmitted in the nth subframe is the first control channel element (CCE) index n _CCE of the PDCCH transmitted in the nth subframe and the higher layer signaling. is transmitted in the n + 4th subframe using resource index n ⁽¹⁾ _PUCCH , which is the sum of the value N ⁽¹⁾ _PUCCH obtained through signaling) or a separate control channel. N ⁽¹⁾ _PUCCH is the total number of PUCCH format 1 / 1a / 1b resources required for Semi-Persistent Scheduling (SPS) transmission and Service Request (SR) transmission. In the semi-static scheduling transmission and the SR transmission, since the PDCCH indicating the PDSCH transmission does not exist, the base station explicitly informs the UE of n ⁽¹⁾ _PUCCH .

When the HARQ ACK / NACK signal and / or the SR are transmitted through the PUCCH format 1 / 1a / 1b, the physical RB index n _PRB is determined by the resource index n ⁽¹⁾ _PUCCH . This is shown in Equation 1 below.

<Equation 1>

Accordingly, the physical RB index n _PRB is determined according to the resource index n ⁽¹⁾ _PUCCH , and the PUCCH corresponding to each m is frequency hopping in units of slots.

In a carrier aggregation (CA) environment, HARQ ACK / NACK signals for a plurality of downlink component carriers are transmitted through one uplink component carrier. In this case, one bit of an ACK / NACK signal is transmitted per one codeword (CW).

The HARQ ACK / NACK signal for the downlink is transmitted on the PUCCH.

For transmission of the HARQ ACK / NACK signal, the base station may implicitly allocate the ACK / NACK resource index. Implicitly allocating an ACK / NACK resource index means that the base station allocates a resource index calculated by using n _CCE , which means a number of _CCEs , as a parameter among at least one CCE constituting the PDCCH of CC # a. In the present specification, in response to the implicit resource index allocation of the base station, it is expressed as 'implicit resource index acquisition' from the perspective of the terminal.

The base station may also assign the resource index explicitly. The fact that the base station explicitly allocates the resource index to the terminal means that the resource index of the PUCCH dedicated to the specific terminal is allocated to the terminal through a separate resource allocation indicator from the base station without depending on n _CCE . . In this case, the separate resource allocation indicator from the base station includes signaling from an upper layer or a physical layer. In addition, the resource allocation indicator may be included in the PDCCH as control information or system information. In the present specification, in response to the explicit resource index allocation of the base station, it is expressed as 'explicit resource index acquisition' from the perspective of the terminal.

The base station may use 2 bits to transmit the ACK / NACK Resource Indicator (ARI, hereinafter referred to as "ARI") to be used for transmitting the TPC command. The ARI is an indicator for explicitly allocating a resource to be used when the terminal transmits a HARQ ACK / NACK signal for downlink.

In the CA environment, the TPC field of the PDCCH corresponding to the PDSCH on the major carrier may be used as a TPC command, and the TPC field of the PDCCH corresponding to the PDSCH on the subcarrier may be used as the ARI. Even in a TDD using a single carrier, a TPC field transmitted on a PDCCH of a specific downlink subframe is used as a TPC command, and a bit to be allocated to a TPC field on a PDCCH of another downlink subframe is used. ARI can be sent.

Information of the ARI mapping table for allocating resources to the ARI may be transmitted to the terminal in advance by higher layer signaling. The ARI mapping table consists of the values indicated by the ARI and the ACK / NACK transmission resources allocated accordingly.

In a CA environment, the number of HARQ ACK / NACK transmission resources required to configure the ARI mapping table is a transmission mode for the number of component carriers configured through RRC and the number of codewords for each component carrier in a subframe, HARQ It may be determined through the type of the PUCCH format for transmitting the ACK / NACK signal. In addition, in case of TDD using a single carrier, the number of downlink subframes associated with an uplink subframe may be determined according to the type of PUCCH format for transmitting HARQ ACK / NACK signals. The ARI mapping table can be configured differently according to the number of ACK / NACK transmission resources corresponding to four values that can be represented by a 2-bit ARI. The explicitly allocated resource set and the corresponding ARI value are determined by higher layer signaling. It may be delivered to the terminal in advance.

Table 2 shows an embodiment of the ARI mapping table used in the present invention.

TABLE 2

Table 2 is an ARI mapping table configured for convenience of description of the present invention, the ARI mapping table according to the present invention can be configured in various ways within the spirit of the present invention. The resource set N _k ( K = 1, 2, 3, 4) is a resource set whose elements are the same number of resources as the number of transmission resources to be allocated through the ARI. For example, in the case of allocating one transmission resource through ARI, each N _k is a set of resources (for example, {n} and n are transmission resources) having one transmission resource that does not overlap each other, and through ARI In the case of allocating two transmission resources, each N _k is a resource set (e.g. {n1, n2}) having two transmission resources as elements.

At this time, the resource set indicated by the ARI on the ARI mapping table is allocated to the terminal. For example, when the value of the ARI is '01', transmission resources of resource set N ₂ are allocated.

On the other hand, HARQ ACK / NACK response of 4 bits or less can transmit the HARQ ACK / NACK signal through the PUCCH format 1b using the channel selection.

The channel selection allocates HARQ ACK / NACK resources for downlink by using a table that maps a message to be transmitted, a resource to be used for transmission of the message, and a modulation symbol. The channel selection table may be composed of a combination of a plurality of resource indexes and modulation symbols of the ACK / NACK signal. Since a channel selection can allocate resources necessary for transmitting a signal of up to 4 bits, for an ACK / NACK signal having 4 bits or less, the channel selection table is set according to the value of the number of bits (M) required for transmitting the ACK / NACK signal. Can be configured. The terminal may allocate an ACK / NACK resource and transmit a symbol by using the channel selection table.

The format of the table used for channel selection may be delivered to the terminal and the base station in advance by higher layer signaling. The terminal may explicitly obtain an ACK / NACK resource index for constructing a table used for channel selection.

Table 3 is an example of a table for channel selection when the M value (the number of HARQ ACK / NACK signals to be transmitted as one symbol value) is three.

TABLE 3

In Table 3, HARQ-ACK (0) ~ HARQ-ACK (3) is an ACK / NACK type for the codeword to determine whether or not normally received (decoded).

n ⁽¹⁾ _PUCCH is a HARQ ACK / NACK resource to be used for transmission using PUCCH format 1b. In this case, each ACK / NACK resource constituting the table for channel selection, for example, {n ⁽¹⁾ _{PUCCH, 0} , n ⁽¹⁾ _{PUCCH, 1} , n ⁽¹⁾ _{PUCCH, 2} } in Table 3 are as described above. Likewise implicitly or explicitly allocated transmission resources.

b (0) b (1) is a QPSK symbol of an ACK / NACK signal to be transmitted. When the values of b (0) and b (1) are mapped to N / A, that is, in the case of DTX (Discontinuous Transmission), for example, when the UE does not receive the PDCCH, the UE transmits a HARQ ACK / NACK signal. Do not send an ACK / NACK response in the transmitting subframe.

When the UE allocates a resource using channel selection, the UE transmits a corresponding transmission symbol using an ACK / NACK transmission resource (n ⁽¹⁾ _PUCCH ) mapped to an ACK / NACK type corresponding to a decoding result of received PDSCHs. b (0), b (1)) are transmitted on the PUCCH. For example, when all types of ACK / NACK signals to be transmitted are ACK, the value (1,1) of the corresponding symbol (b (0), b (1)) using ACK / NACK resource n ⁽¹⁾ _{PUCCH, 1} ) Is transmitted on the PUCCH.

The uplink transmission and the downlink transmission may use a time division duplex (TDD) scheme that is transmitted using different times, or may use a frequency division duplex (FDD) scheme that is transmitted using different frequencies.

In the case of FDD, there are carrier frequencies used for uplink transmission and carrier frequencies used for downlink transmission, respectively, so that uplink transmission and downlink transmission can be simultaneously performed in a cell.

In the case of TDD, uplink transmission and downlink transmission are always distinguished in time based on one cell. The base station and the terminal repeat the switching between the transmission mode and the reception mode. In the case of TDD, a special subframe may be provided to provide a guard time for mode switching between transmission and reception.

Table 4 shows configuration of uplink and downlink in TDD mode.

TABLE 4

As shown in Table 4, the base station and the terminal performs uplink and downlink transmission through seven possible downlink / uplink frame settings. In a frame structure composed of 10 subframes, 'D' represents a downlink subframe and 'U' represents an uplink subframe. 'S' represents the special subframe described above.

Meanwhile, in the case of FDD, the UE transmits HARQ ACK / NACK for the PDSCH received in subframe n-4 in subframe n.

In the case of TDD, the UE transmits HARQ ACK / NACK for the PDSCH received in subframe (s) n-k in uplink subframe n. In this case, k is an element of K, K may be defined by Table 5.

TABLE 5

In Table 5, subframes in which numbers are written are subframes for performing uplink transmission.

As shown in Table 5, the HARQ ACK / ANCK signal for the downlink subframe may be transmitted through an uplink subframe associated with the downlink subframe.

Even in the case of a TDD system using a single carrier (SC), referring to Table 5, in the remaining configurations except for configurations 0 and 6 of uplink-downlink configuration, two or more downlink subframes have one uplink. It can be confirmed that it is associated with the link subframe. In this case, in the downlink subframes associated with the same uplink subframe, the TPC may be transmitted on the PDCCH for power control of the same uplink PUCCH. Therefore, for one PUCCH, an ARI can be transmitted by using bits to be allocated to overlapping TPC fields, and a table for channel selection is constructed using ACK / NACK resources obtained implicitly or explicitly, and using the HARQ An ACK / NACK signal may be transmitted.

Meanwhile, referring to Table 5, when the HARQ ACK / NACK signals for many downlink subframes need to be transmitted in one uplink subframe as in the case of uplink-downlink configuration 5, the individual downlink subframes Many transmission bits are required to transmit the HARQ ACK / NACK symbol for. For example, when two codewords are transmitted for each downlink subframe, up to 18 bits are required to transmit a HARQ ACK / NACK signal for each downlink subframe. Accordingly, a method of transmitting an ACK / NACK signal for each downlink subframe by time domain bundling may be considered.

The plurality of HARQ ACK / NACK signals may be bundled by a logical product operation. That is, when all HARQ ACK / NACK information for the downlink component carrier or the downlink subframe to be bundled is ACK, the ACK may be transmitted as a HARQ ACK / NACK signal representing the bundled ACK / NACK signal. When HARQ ACK / NACK information on at least one CC or subframe is NACK, NACK may be transmitted as a HARQ ACK / NACK signal representing a bundled ACK / NACK signal. In addition, when HARQ ACK / NACK information for at least one CC or subframe is DTX, the DTX may be transmitted as a HARQ ACK / NACK signal representing the bundled ACK / NACK signal.

However, even when bundling is used, there may be a case where a HARQ ACK / NACK response to be transmitted exceeds 4 bits or a multiplexing HARQ ACK / NACK signal is performed without bundling.

In this regard, PUCCH format 3 may be used. PUCCH format 3 is a PUCCH format to which Discrete Fourier Transform-Spreading-Orthogonal Frequency-Division Multiplexing (DFT-S-OFDM) is applied, and uses DFT-IFFT and block-spreading. In case of transmitting HARQ ACK / NACK signal using PUCCH format 3, as one ACK / NACK resource, up to 10 bits of information in FDD and up to 20 bits of information in TDD are used as HARQ ACK / NACK signals. Can transmit

Even in a TDD system using a single carrier, if the PUCCH format 3 is used, HARQ ACK / NACK signals having a maximum length of 20 bits can be transmitted. Therefore, even in the uplink-downlink configuration 5, HARQ ACK / NACK signals can be multiplexed and transmitted. . Even when the payload size of up to 20 bits is exceeded, ACK / NACK signals may be transmitted through spatial bundling.

However, unlike a CA environment, in case of a time division duplex (TDD) using a single carrier in downlink, how to allocate a transmission resource to transmit a HARQ ACK / NACK signal in PUCCH format 3 is a problem. In the present invention, a single carrier for TDD (TDD) using a single carrier may be a CA or TDD system in which a transmission is performed between a base station and a base station that do not support a CA (Carrier Aggregation) environment. , But includes a case of a TDD system in which transmission is performed using a single carrier between a terminal and a base station.

Hereinafter, a method of allocating a resource of PUCCH format 3 for HARQ ACK / NACK signal transmission for a TDD system using a single carrier to which the present invention is applied will be described.

<Fixed allocation of resources>

A method of explicitly allocating a resource of PUCCH format 3 through higher layer signaling such as RRC may be considered. The base station fixedly allocates a predetermined transmission resource through higher layer signaling such as RRC, and the terminal may transmit a HARQ ACK / NACK signal by using the same.

Even when SORTD is applied, the base station can allocate resources in a fixed manner. The base station explicitly allocates resources through higher layer signaling according to the number of transmit antennas applying SORTD. For example, in the case of using two transmit antennas, the base station may allocate two resources of PUCCH format 3 through higher layer signaling, and in the present embodiment, the transmission resources allocated to specific terminals are fixed to specific resources. .

<Allocating Resources Using Resource Indicators>

In a TDD system using a single carrier, in order to transmit HARQ ACK / NACK signals, resources of PUCCH format 3 of an uplink subframe associated with a downlink subframe are allocated using a resource indicator, for example, an ACK / NACK Resource Indicator (ARI). You can think of how to do it.

The base station may transmit the ARI by dedicating bits to be allocated to the TPC field transmitted on the PDCCH of the downlink subframe associated with the uplink subframe. From now on , unless otherwise stated, the expression "dedicate a bit to be allocated to a TPC field" is referred to as "using a TPC field". Also, from now on, the ARI transmitted on the PDCCH of the downlink subframe herein is an ARI transmitted using the TPC field unless otherwise specified.

The UE may use the resource indicated by the ARI as a resource of PUCCH format 3 for transmitting HARQ ACK / NACK signals in an uplink subframe associated with a downlink subframe in which the ARI is transmitted.

In a TDD system using a single carrier, the UE may transmit a HARQ ACK / NACK signal using one PUCCH format 3 resource. Therefore, when one ACK / NACK transmission resource described above is required (Table 2), an ARI mapping table may be configured with a resource of PUCCH format 3. The base station may configure the ARI to indicate a resource of one PUCCH format 3 on the ARI mapping table.

Even when transmitting a HARQ ACK / NACK signal in PUCCH format 3 in a TDD system using a single carrier, SORTD may be applied by allocating a plurality of transmission resources through an ARI. In this case, a plurality of transmission resources may be allocated corresponding to the number of transmission antennas to which SORTD is applied. For example, the second case of applying the SORTD to transmit antennas, and assigns the two transmission resources by ARI, Correspondingly, if two ACK / NACK transmission resource the ARI mapping table is required (the N _k two transmission in Table 2 If you have a resource as an element).

As to whether the terminal performs uplink transmission by applying SORTD, the base station may transmit an indication to the terminal through higher layer signaling such as RRC signaling.

When two or more downlink subframes are associated with an uplink subframe

Here, the case in which two or more downlink subframes are associated with an uplink subframe means that at least two or more of downlink subframes associated with the uplink subframe are scheduled. Accordingly, in the present invention, an uplink subframe and a downlink subframe mean a scheduled subframe.

Among the downlink subframes associated with the uplink subframe, the TPC field on the PDCCH transmitted in at least one downlink subframe is used as a TPC command. An ARI may be transmitted using a TPC field on a PDCCH transmitted in at least one subframe among the remaining downlink subframes. The resource indicated by the ARI may be allocated as a resource of PUCCH format 3 for transmitting HARQ ACK / NACK signals through an uplink subframe associated with a downlink subframe in which the ARI is transmitted.

FIG. 1 illustrates uplink-downlink configuration 5 in a TDD system using a single carrier.

Referring to FIG. 1, in uplink-downlink configuration 5, subframe # 9 of frame # 0 and subframes 0, 1, 3, 4, 5, 6, 7, and 8 of frame # 1 are DL subframes. It is associated with an uplink subframe (subframe 2) of frame # 2. In this case, any one of downlink subframes (subframe 9 of frame # 0 and 0, 1, 3, 4, 5, 6, 7, 8 subframes of frame # 1) associated with the uplink subframe The TPC field on the PDCCH transmitted in the subframe may be used as a TPC command for power control of the PUCCH transmitted in the uplink subframe (subframe # 2 of frame # 2). The base station determines downlink subframes (subframe 9 of frame # 0 and 0, 1, 3, 4, 5, and 6 of frame # 1) associated with the uplink subframe (subframe 2 of frame # 2). , 7, 8 subframes), ARI may be transmitted using a TPC field of a PDCCH transmitted on a subframe other than the subframe in which the TPC command is transmitted.

Preferably, the TPC field of a downlink subframe having a value of Downlink Assignment Indicator (DAI) equal to 0 may transmit a TPC command, and may transmit an ARI using another TPC field of another downlink subframe. Downlink Assignment Indicator (DAI) is a 2-bit message transmitted on a PDCCH. In the case of TDD, a subframe in which a corresponding subframe is assigned to a single uplink subframe and assigned to a subframe among the downlink subframes scheduled for the second time Indicates whether or not it is a frame. Through this, the PUCCH transmission power can be adaptively adjusted. For example, in FIG. 1, a TPC command for PUCCH transmitted in subframe 2 of frame # 2 may be transmitted through a TPC field in subframe 9 of frame # 0 (DAI = 0). In this case, the base station may transmit the ARI using the TPC field transmitted on the PDCCH in the remaining downlink subframes other than the subframe 9 of the frame # 0.

In addition, a TPC command may be transmitted in a TPC field of a downlink subframe closest to the associated uplink subframe. This is because the most recent channel state may be reflected with respect to the uplink transmission time.

In each case described above, the values indicated by the ARI transmitted in the downlink subframe associated with one uplink subframe may be set to the same value.

By transmitting ARI using a TPC field in a downlink subframe other than a downlink subframe that transmits a TPC command, by allocating a plurality of transmission resources through the ARI, a UE using a multi-antenna system applies SORTD to HARQ ACK. It is also possible to transmit a / NACK signal. When SORTD is applied, a plurality of transmission resources may be allocated corresponding to the number of transmission antennas. For example, the second case of applying the SORTD to transmit antennas, and assigns the two transmission resources by ARI, Correspondingly, if two ACK / NACK transmission resource the ARI mapping table is required (the N _k two transmission in Table 2 If you have a resource as an element).

In this case, all of the values indicated by the ARIs transmitted in the downlink subframes associated with one uplink subframe may be set to the same value. You can also do that. For example, SORTD is applied using two transmit antennas, and when three or more downlink subframes are associated with one uplink subframe, a TPC command is transmitted to a TPC field of a subframe having DAI of 0, and the DAI is Allocates a transmission resource for the first antenna with an ARI transmitted using a TPC field of a subframe of 1, and allocates a transmission resource for a second antenna with an ARI transmitted using the TPC field of a subframe with a DAI of 2. You can do that.

If PDCCH in a Downlink Subframe Is Missing-Contrast mother Fallback mode

If the PDCCH of the downlink subframe in which the TPC command for the uplink subframe is transmitted is missed, the conventionally received TPC command may be reused for the PUCCH transmission of the uplink subframe, or the currently configured PUCCH The transmission power can be maintained. For example, if the conventionally received TPC command was a command to lower the transmission power by 1 dB, when the TPC command is lost in the transmission process, the terminal may reuse the conventional TPC command to lower the transmission power of the PUCCH by 1 dB. In addition, instead of lowering the transmission power of the PUCCH by 1 dB, the terminal may maintain the transmission power of the currently set PUCCH as it is. If the PDCCH of the downlink subframe in which the TPC command for the uplink subframe is transmitted is missed, whether to reuse the conventional TPC command or maintain the currently set PUCCH transmission power through higher layer signaling such as RRC It may be determined or may be set in advance in the terminal.

SORTD can be applied even when the TDC command does not receive the PDCCH transmitted. In this case, there is no difference from the above-described application method of SORTD except for reusing the previously received TPC command or maintaining the currently set transmission power.

When the PDCCH of the downlink subframe in which the TPC command for the uplink subframe is transmitted is received, but the ARI which allocates the resource of PUCCH format 3 does not receive the PDCCH of the downlink subframe, the UE transmits a transmission resource. Can be implicitly assigned. The UE switches the transmission mode to transmit the ACK / NACK signals by bundling the codewords in the time domain for each codeword or by multiplexing HARQ ACK / NACK signals by using a channel selection or the like, and uses an implicitly allocated transmission resource. HARQ ACK / ANCK signal can be transmitted.

Although the PDCCH of the downlink subframe in which the TPC command for the uplink subframe is transmitted is received, even when the ARI which allocates the resource of PUCCH format 3 does not receive the PDCCH of the downlink subframe, the UE receives SORTD. It can be applied to transmit the HARQ ACK / NACK signal.

For example, in the case of applying SORTD using two transmission antennas, the UE, as described above with respect to Table 1, the first Control Channel Element (CCE) index n _CCE of the PDCCH transmitted in the received subframe and the following. Two transmission resources may be implicitly allocated based on the CCE index n _CCE +1. Therefore, the UE can apply SORTD through the two transmission resources obtained. In this case, the UE may perform HARQ response even with an implicitly allocated transmission resource by performing bundling for each codeword in the time domain as needed.

When one downlink subframe is associated with an uplink subframe

When one downlink subframe is associated with an uplink subframe, as shown in uplink-downlink configuration 0, 1, or 6 of Table 5, the corresponding uplink subframe is originally associated with one downlink subframe. In addition to the present case, only one downlink subframe is scheduled for an uplink subframe associated with the plurality of downlink subframes.

When an uplink subframe is associated with one downlink subframe, a TPC command may be transmitted in a TPC field transmitted on the PDCCH of this downlink subframe. Accordingly, the terminal can continuously adjust the uplink transmission power adaptively.

FIG. 2 illustrates uplink-downlink configuration 1 in a TDD system using a single carrier. Referring to FIG. 2, two downlink subframes of frame # 0 are associated with subframe # 2, which is an uplink subframe of frame # 1, and frame # 0 is assigned to subframe # 3, which is an uplink subframe of frame # 1. One downlink subframe of is associated.

In this case, with respect to the PUCCH transmitted in subframe # 1 of frame # 1, resources may be allocated according to the resource allocation method of PUCCH format 3 described above when "uplink subframe is associated with two or more downlink subframes". have.

For subframe # 3 of frame # 1, PUCCH transmission power may be controlled according to a TPC command transmitted in a TPC field on PDCCH of subframe # 9 of frame # 0. In this case, the UE switches the transmission mode to bundle and transmit the ACK / NACK signals in the time domain or multiplexes the HARQ ACK / NACK signals by using a channel selection or the like, and implicitly allocates transmission resources to receive the HARQ ACK. / NACK signal can be transmitted.

Even if an uplink subframe is associated with one downlink subframe and a TPC command is transmitted in the downlink subframe, the UE may transmit a HARQ ACK / NACK signal by applying SORTD.

For example, in the case of applying SORTD using two transmission antennas, the UE, as described above with respect to Table 1, the first Control Channel Element (CCE) index n _CCE of the PDCCH transmitted in the received subframe and the following. Two transmission resources may be implicitly allocated based on the CCE index n _CCE +1. Therefore, the UE can apply SORTD through the two transmission resources obtained. In this case, the UE may perform HARQ response even with implicitly allocated transmission resources by performing bundling in the time domain as needed.

In addition, the base station may transmit the ARI using the TPC field without transmitting the TPC command in the TPC field transmitted on the PDCCH of one downlink subframe associated with the uplink subframe.

In this case, the UE may reuse the previously received TPC command for PUCCH transmission of the uplink subframe or maintain transmission power of the currently set PUCCH. Whether to reuse the conventional TPC command or maintain the currently set PUCCH transmission power may be determined through higher layer signaling such as RRC, or may be preset in the terminal. For example, in FIG. 2, assuming that an ARI using a TPC field is transmitted in subframe 9 of frame # 0, the UE may transmit subframe 5 of frame # 0 or PUCCH for subframe # 3 of frame # 1. The TPC command received in subframe 6 can be reused. In addition, the UE may transmit the PUCCH in the third subframe of the frame # 1 with the transmission power used to transmit the PUCCH in the second subframe of the frame # 1.

Meanwhile, even when one downlink subframe is associated with an uplink subframe, if the ARI is transmitted using the TPC field, as described above, a plurality of transmission resources are allocated through the ARI transmitted to the terminal. A terminal using a transmission antenna may apply SORTD to transmit a HARQ ACK / NACK signal.

When one downlink subframe is associated with an uplink subframe, whether to transmit a TPC command or an ARI in the TPC field of this downlink subframe may be predetermined between the terminal and the base station, It may be delivered to the terminal through higher layer signaling.

Fixed downlink subframe transmitting ARI

In each frame, the ARI may be transmitted using a TPC field on the PDCCH only in a specific downlink subframe. For example, for each uplink-downlink configuration of Table 5, a downlink subframe capable of transmitting ARI in each frame may be configured. In this case, the UE may transmit a HARQ ACK / NACK signal using a resource of PUCCH format 3 indicated by the received ARI until the ARI is transmitted in the next frame. Accordingly, resources of PUCCH format 3 may be semi-dynamically allocated every frame.

In this case, one or more subframes capable of transmitting ARI may be specified for each frame. That is, depending on the channel environment or the load of the network system, the period of ARI transmission is set to 5ms, 10ms, etc., or the index of subframes dedicated to ARI transmission is set to subframe 1, subframe 3, and the like. By doing so, it is possible to specify a downlink subframe for transmitting the ARI.

Setting of an ARI transmission period or setting of a dedicated subframe index may be performed through RRC signaling or the like.

FIG. 3 schematically illustrates an example of specifying a downlink subframe for transmitting ARI in uplink-downlink configuration 2 in a TDD system using a single carrier. Referring to FIG. 3, the ARI is transmitted in subframes 0 and 5 specified in each frame. 3 may also be regarded as a case in which the ARI is transmitted every 5ms.

Meanwhile, even when the downlink subframe transmitting the ARI is fixed, a plurality of transmission resources are allocated through the ARI transmitted to the terminal, so that the terminal using the multi-transmission antenna applies a SORTD to transmit a HARQ ACK / NACK signal. Can be sent.

Use of ARI windows

A window to which an ARI transmitted on a PDCCH of a specific downlink subframe is applied may be set, and resources of a PUCCH format 3 may be allocated to an uplink subframe located in the window using the same ARI.

The ARI window may be set for each ARI transmitted on the PDCCH of the downlink subframe. In addition, the ARI window may be configured only for the ARI transmitted on the PDCCH of a specific downlink subframe. The downlink subframe for transmitting the ARI may be specified, and the length of the ARI window to which the ARI transmitted in the corresponding downlink subframe is applied may be set according to the transmission interval or transmission period of the ARI. The ARI transmission interval or transmission period and the length of the ARI window may be preset between the terminal and the base station or may be delivered to the terminal through RRC signaling.

FIG. 4 schematically illustrates an example of configuring an ARI window for uplink-downlink configuration 0 in a TDD system using a single carrier. Referring to the example illustrated in FIG. 4, the ARI is transmitted in downlink subframe 0, which is associated with subframe 4 that is an uplink subframe. In the case of Fig. 4, the transmission period of the ARI is set to 10 ms. The uplink subframes other than the uplink subframes (subframes 3 and 8) that do not transmit the HARQ ACK / NACK signal for the downlink transmission are in the PUCCH format 3 indicated by the ARI of the ARI window to which they belong. The HARQ ACK / NACK signal may be transmitted using the resource.

FIG. 5 schematically illustrates an example of configuring an ARI window for uplink-downlink configuration 1 in a TDD system using a single carrier.

The ARI windows for ARIs transmitted on the PDCCH of each downlink subframe may be configured to overlap in time. In this case, an ARI window that is applied first may be designated for an uplink subframe located in a place where a plurality of ARI windows overlap. For example, an ARI transmitted through a specific subframe may be set to be applied first, or a new ARI window may be applied first in time. The method of selecting an ARI window to be applied first may be preset between the terminal and the base station or may be delivered to the terminal through RRC signaling.

When a new ARI window is applied first in time, HARQ ACK / NACK signal transmission may be performed using a resource of PUCCH format 3 indicated by ARI 2 in subframe 3 of frame # 1 of FIG. 5.

On the other hand, even when using the ARI window, by transmitting a plurality of transmission resources through the ARI delivered to the terminal, the terminal using the multiple transmit antenna can be applied to SORTD to transmit the HARQ ACK / NACK signal.

Consideration of Uplink-Downlink Configuration- Resource Allocation Method

In consideration of each uplink-downlink configuration of Table 5, a resource of PUCCH format 3 for HARQ ACK / NACK signal transmission may be allocated to an uplink subframe.

For example, in the case of uplink-downlink configuration 0, configuration 1, and configuration 6, there is an uplink subframe associated with only one downlink subframe. Therefore, in this case, it is conceivable to allocate resources of PUCCH format 3 in a manner different from other downlink-uplink configurations. That is, a method of transmitting a TPC command may be considered as a TPC field transmitted in one downlink subframe. In this case, the terminal may be implicitly allocated a transmission resource. The UE switches the transmission mode to transmit the ACK / NACK signals by bundling the codewords in the time domain for each codeword or by multiplexing HARQ ACK / NACK signals by using a channel selection or the like, and uses an implicitly allocated transmission resource. HARQ ACK / ANCK signal can be transmitted.

As such, even though the PDCCH of the downlink subframe in which the TPC command for the uplink subframe is transmitted is received, even if the PDCCH of the downlink subframe in which the ARI for allocating the resources of PUCCH format 3 is not received, the UE As described above, the HARQ ACK / NACK signal may be transmitted by applying SORTD.

Meanwhile, the HARQ ACK / NACK resource may be allocated to the uplink-downlink configuration 1 to the configuration 5 through the above-described various methods.

Considering Uplink-Downlink Configuration- Codebook Size

Even in a TDD system using a single carrier to which the present invention is applied, a codebook size of PUCCH format 3 to be used needs to be determined in order to accurately transmit and receive data between a terminal and a base station.

For example, referring to Table 5, in case of UL-DL configuration 3, up to 6 bits of HARQ ACK / NACK signals may be transmitted in one UL subframe. That is, HARQ ACK / NACK signals for subframes 1, 5, and 6 of the previous frame are transmitted to subframe 2, which is an uplink subframe. In this case, if two codewords are transmitted to subframes 1, 5, and 6, which are downlink subframes, up to 6 bits of HARQ ACK / NACK signals are transmitted.

However, even in this case, only some of subframes 1, 5, and 6 may be scheduled, and only one codeword may be transmitted in a downlink subframe. In addition, HARQ ACK / NACK signals for up to two downlink subframes are transmitted to subframes 3 and 4, which are uplink subframes, respectively.

Therefore, between the terminal and the base station, it is necessary to determine the number of bits (codebook size) that the terminal uses when transmitting a HARQ ACK / NACK signal using PUCCH format 3.

As described in the foregoing example, the codebook size is the maximum HARQ that can be transmitted through one uplink subframe according to the number of codewords transmitted in the uplink-downlink configuration and the downlink subframe, that is, the downlink transmission mode. It may be determined by the number of bits of the ACK / NACK signal.

For example, in the case of uplink-downlink configuration 3, if only two downlink subframes are scheduled in association with subframe 2, which is an uplink subframe, a NACK signal is transmitted for an unscheduled downlink subframe. To fill the codebook size. In addition, even when the HARQ ACK / NACK signal is transmitted in subframe 3 in the uplink-downlink configuration 3, in addition to the HARQ ACK / NACK signal for two associated downlink subframes, the number of bits of the remaining PUCCH format 3 For example, the NACK signal may be transmitted to fill the codebook size.

Accordingly, the base station always processes bits having a predetermined size as HARQ ACK / NACK signals among the signals transmitted on the PUCCH in PUCCH format 3 according to an uplink-downlink configuration and a downlink transmission mode defined between the UE. can do.

Even when Semi-Persistent Scheduling (SPS) is applied in a CA environment, an ARI may be transmitted using a TPC field transmitted on a PDCCH activating the SPS. At this time, the base station may allocate a transmission resource to be used for the terminal to transmit the HARQ ACK / NACK response on the PUCCH through the ARI.

Even when the SPS is applied, SORTD may be applied to the HARQ ACK / NACK response signal transmission of the terminal. For example, the base station can transmit the HARQ ACK / NACK signal by applying the SORTD by transmitting an ARI that allocates two transmission resources by using the TPC field transmitted on the PDCCH of the major carrier. In addition, the base station transmits an ARI that allocates one transmission resource by using a TPC field transmitted on a PDCCH of a major carrier and another by using a TPC field transmitted on a PDCCH of a subcarrier to which SPS is not applied. By transmitting an ARI for allocating transmission resources, the terminal may be configured to transmit a HARQ ACK / NACK signal by applying SORTD.

Meanwhile, a transmission scheme that the terminal uses for HARQ ACK / NACK transmission is transmitted from the base station to the terminal through higher layer signaling. For example, a PUCCH format, a resource allocation scheme, whether to apply SORTD, etc. used by a UE to transmit an HARQ ACK / NACK signal are transmitted from the base station to the UE through higher layer signaling.

However, in this case, when the UE cannot transmit the HARQ ACK / NACK signal according to the method transmitted from the base station to the UE through higher layer signaling, how to determine the fallback mode as a method of transmitting the HARQ ACK / NACK signal. It matters.

In the present invention, the fallback mode is a HARQ ACK / NACK signal in PUCCH format 3 according to a predetermined method between the terminal and the base station or a method indicated by the base station through higher layer signaling (hereinafter, referred to as 'normal mode'). This means that the UE transmits the HARQ ACK / NACK signal using another scheme, for example, another PUCCH format, another resource allocation scheme, and / or another transmission scheme.

For example, in a CA environment of TDD, a plurality of component carriers are configured for a terminal and a normal mode is determined correspondingly, but when one component carrier is scheduled only in one downlink subframe, a contrast mode is applied. Can be. In addition, in the CA environment of the TDD, a normal mode is defined such that a TPC command is transmitted in a TPC field of a major carrier and an ARI is transmitted using a TPC field of a subcarrier, but only a major carrier is scheduled or only a minor carrier is received. Contrast mode can also be applied. That is, the contrast mode may also be predetermined between the terminal and the base station, and information about the contrast mode may be transmitted from the base station to the terminal through higher layer signaling.

Contrast mode-for dynamic scheduling / when SPS releases by PDCCH>

Method of setting the transmission mode of the contrast mode the same as the transmission method of the normal mode

(1) In the normal mode, a HARQ response signal is transmitted in PUCCH format 3 by applying a single antenna or SORTD, but only one subframe is received by a major carrier (DAI = 1)

In this case, PUCCH format 1a / 1b may be used instead of PUCCH format 3 as a transmission format.

In this case, if 2CW is transmitted as a major carrier and PUCCH format 1a is used to transmit HARQ ACK / NACK signals, spatial bundling may be performed for signal transmission of 1 bit.

(2) The normal mode was a method of transmitting a HARQ response signal in PUCCH format 3 by applying a single antenna or SORTD, but when a plurality of subframes are received only by major carriers (DAI> 1)

If the sub-carrier or subframe that transmits the ARI is unscheduled or missing, the HARQ response signal is transmitted based on the control channel element (CCE) index n _CCE for the PDCCH of the received downlink subframe. The transmission resource may be allocated implicitly. For example, based on the PDCCH of the subframe with DAI = 1, transmission resources may be allocated through n _CCE as shown in Table 1, and when SORTD is applied, resources may be implicitly allocated to each antenna. have.

In this case, PUCCH format 1a / 1b may be used instead of PUCCH format 3 as a transmission format.

In order to transmit the HARQ ACK / NACK signal in the contrast mode, bundling may be required. In bundling, only time domain bundling may be performed in consideration of a size of a signal to be transmitted, or time bundling and spatial bundling may be performed together.

FIG. 6 is a diagram schematically illustrating an example of performing time domain bundling to transmit an HARQ ACK / NACK signal using PUCCH format 1b. In FIG. 6, for convenience of description, four downlink subframes associated with one uplink subframe are transmitted using only a small carrier and 2CW is transmitted in each downlink subframe as an example. In FIG. 6, the number of subframes is a number according to a received order for a downlink subframe associated with one uplink subframe.

Referring to FIG. 6, a 1-bit bundled signal S1 may be obtained by time-domain ACK / NACK signals A1, B1, C1, and D1 for each downlink subframe of a major carrier. Similarly, ACK / NACK signals A2, B2, C2, and D2 for each downlink subframe of a major carrier may be time-domain-bundled to obtain a 1-bit bundled signal S2. The UE may transmit the 2 bit signal S1S2 by applying SORTD using a transmission resource of PUCCH format 1b implicitly allocated through the PDCCH received in the last or other subframe.

FIG. 7 is a diagram schematically illustrating an example of performing spatial bundling and time domain bundling to transmit an HARQ ACK / NACK signal using PUCCH format 1a. In FIG. 7, for convenience of description, four downlink subframes associated with one uplink subframe are transmitted only as major carriers, and 2CW is transmitted in each downlink subframe as an example. In FIG. 7, the number of subframes is a number according to a received order for a downlink subframe associated with one uplink subframe.

Referring to FIG. 7, first, spatial bundling may be performed for each subframe to obtain bundled ACK / NACK signals B, C, and D. Subsequently, time-domain bundling of the ACK / NACK signals A, B, C, and D may provide one-bit bundled ACK / NACK signal S. FIG. The UE may transmit by applying SORTD by using two resources of PUCCH format 1a, which is implicitly allocated the 1-bit ACK / NACK signal S.

On the other hand, in the case of single antenna transmission, channel selection may be used as the contrast mode. In case of using the channel selection, a transmission resource required may be implicitly allocated as shown in Table 1.

The transmission mode in contrast mode is independent of the transmission mode in normal mode. To set Occation

The transmission mode of the contrast mode may be set independently of the transmission mode of the normal mode. For example, when the HARQ response signal is transmitted through a single antenna in the normal mode, in contrast mode, the HARQ response signal is transmitted using SORTD or the HARQ response signal is transmitted through a single antenna without considering the transmission mode of the normal mode. Can be set. Also, even when the HARQ response signal is transmitted by applying SORTD in the normal mode, in contrast mode, the HARQ response signal is transmitted by applying the SORTD or the HARQ response signal is transmitted through a single antenna without considering the transmission mode of the normal mode. Can be set to

Even in this case, in order to transmit the HARQ ACK / NACK signal in the contrast mode, PUCCH format 1a or PUCCH format 1b may be used and bundling may be required.

Transmission resources for transmitting HARQ ACK / NACK signals in PUCCH format 1a and PUCCH 1b are implicitly allocated as shown in Table 1 based on the control channel element (CCE) index n _CCE for the PDCCH of the received downlink subframe. Can be.

When setting the transmission mode of the contrast mode to the single antenna transmission method

When the contrast mode is applied, it may be set to use only a transmission method using a single antenna as a transmission method of the HARQ response signal.

Accordingly, in order to transmit the HARQ ACK / NACK signal in the contrast mode, PUCCH format 1a or PUCCH format 1b may be used and bundling may be required.

Transmission resources for transmitting HARQ ACK / NACK signals in PUCCH format 1a and PUCCH 1b are implicitly allocated as shown in Table 1 based on the control channel element (CCE) index n _CCE for the PDCCH of the received downlink subframe. Can be.

<Contrast mode-if SPS is enabled>

Contrast mode can also be considered when the SPS is active. Since the SPS is applied only to the major carriers, the allocation of transmission resources by dynamic scheduling may be applied to the subcarrier, and the dynamic scheduling may be applied to the minor carriers in the subframe to which the SPS is not applied.

8 is a diagram schematically illustrating an example of a normal mode when an SPS is activated. For convenience of description, FIG. 8 illustrates a configuration in which four downlink subframes are associated with one uplink subframe as an example. In FIG. 8, an "X" indicates that an element carrier is not scheduled or lost during transmission in a corresponding subframe. Referring to FIG. 8, SPS is applied to major carriers of subframe # 0.

In the normal mode, the HARQ ACK / NACK signal for the downlink subframes and the component carriers of FIG. 8 may be transmitted through one component carrier of the associated uplink subframe. In the case where a HARQ ACK / NACK signal is transmitted in PUCCH format 3 in the normal mode, transmission resources may be allocated through an ARI dedicated TPC field transmitted on PUCCH in a subframe to which dynamic scheduling is applied.

Unlike the normal mode, the contrast mode may be applied when only a target to which the SPS is applied is received. For example, in the case where downlink transmission is performed only on a major carrier in a downlink subframe to which an SPS is applied, that is, when a downlink subframe or component carrier in which dynamic scheduling is performed is not transmitted, a contrast mode may be applied.

FIG. 9 is a diagram schematically illustrating an example in which a contrast mode is applied by only transmitting major carriers in which an SPS is transmitted in one downlink subframe. In FIG. 9, for convenience of description, a case where four downlink subframes are associated with one uplink subframe will be described as an example.

The transmission mode of the contrast mode may be set the same as the transmission mode of the normal mode or may be set independently of the transmission mode of the normal mode. In addition, the transmission mode of the contrast mode may be set to be always transmitted using a single antenna. The setting of the contrast mode may be made together with the setting of the normal mode.

Accordingly, the contrast mode can be distinguished from the normal mode in which the HARQ ACK / NACK signal is transmitted in the PUCCH format 3 according to the transmission scheme as follows.

(1) When the contrast mode is a method of transmitting a HARQ response signal by applying the SORTD

Since only a small carrier with SPS is transmitted in one downlink subframe, transmission resource allocation for transmitting a HARQ ACK / NACK signal to the SORTD is required.

SPS activation is performed by the PDCCH of the downlink subframe to which the SPS is applied.

The base station may transmit to the terminal an ARI that allocates two transmission resource indexes to be used in the contrast mode by using the TPC field transmitted on the PDCCH for activating the SPS. The UE may apply SORTD in the contrast mode to two transmission resources indicated by the ARI received on the PDCCH activating the SPS.

In addition, the base station allocates one transmission resource index (n _{PUCCH, 1} ) to be used in the contrast mode by transmitting the ARI by using the TPC field transmitted on the PDCCH for activating the SPS, and the second transmission resource index (n _{PUCCH, 2} ) may be allocated based on a transmission resource index n _{PUCCH, 1} allocated to the ARI, for example, n _{PUCCH, 1} +1. The UE may receive one transmission resource through the ARI received on the PDCCH activating the SPS, and may additionally allocate another transmission resource based on the transmission resource allocated through the ARI to apply SORTD. .

In this case, the transmission resources allocated based on the transmission resources allocated through the ARI and the transmission resources allocated through the ARI may be transmission resources of PUCCH format 1a / 1b, transmission resources of PUCCH format 3, or spatial bundling. This may be done.

(2) When the contrast mode transmits a HARQ response signal using a single antenna

Since only a small carrier with SPS is transmitted in one downlink subframe, transmission resource allocation for transmitting a HARQ ACK / NACK signal for the small carrier is required.

Accordingly, as described above, an ARI for allocating a transmission resource to be used in the contrast mode can be transmitted to the UE by using the TPC field transmitted on the PDCCH for activating the SPS. In this case, the ARI can allocate one transmission resource. have.

In this case, if PUCCH format 1a is used to transmit the HARQ ACK / NACK signal, spatial bundling may be performed. In addition, the HARQ ACK / NACK signal may be transmitted in the PUCCH format 1b using the channel selection.

FIG. 10 is a diagram schematically illustrating a contrast mode applied when there is a subframe and / or a component carrier on which dynamic scheduling is performed. FIG. 10 illustrates a case where four downlink subframes are associated with one uplink subframe for convenience of description.

Referring to FIG. 10, in addition to the component carrier of subframe # 0 to which SPS is applied, the component carrier of subframe # 2 to which dynamic scheduling is applied is transmitted to the terminal.

In this case, when the TPC command is transmitted to the TPC field on the PDCCH transmitted in subframe # 2, the ARI transmitted on the PDCCH for activating the SPS is the same as the contrast mode when only the target to which the above-described SPS is applied is transmitted. The transmission resource may be allocated through.

However, in this case, since two or more downlink subframes are received, bundling may be required when transmitting a HARQ ACK / NACK signal in PUCCH format 1a / 1b.

On the other hand, when the ARI is received through a subframe to which dynamic scheduling is applied, the resource allocation method in the normal mode can be maintained.

11 is a diagram schematically illustrating an example in which a resource allocation scheme may be maintained. In FIG. 11, for convenience of description, a case where four downlink subframes are associated with one uplink subframe will be described as an example.

Referring to FIG. 11, a TPC field transmitted on a PDCCH in downlink subframe # 1 is used to transmit a TPC command, and a TPC field transmitted on a PDCCH in downlink subframe # 3 is used to transmit an ARI. In this case, the terminal may maintain the resource allocation method in the normal mode by receiving these two subframes. For reference, also in the case of FIG. 10, if the PUCCH transmit power does not need to newly transmit a TPC command such as maintaining the current transmit power, if the ARIs are transmitted using the TPC field of the downlink subframe, the ARI is received. Resource allocation in the normal mode may be maintained.

12 is a flowchart schematically illustrating an operation of a base station in a TDD system using a single carrier to which the present invention is applied.

The base station determines an uplink HARQ response method with the terminal (S1210). The base station determines how the HARQ response transmitted by the terminal is configured and transmitted. For example, the base station may determine whether to transmit a HARQ ACK / NACK signal by applying the PUCCH format, resource allocation method, SORTD terminal. At this time, the base station may determine the UL-DL configuration to match the configuration.

The information about the HARQ ACK / NACK response method thus determined may be delivered to the terminal through higher layer signaling. However, this information may be predetermined between the base station and the terminal.

The base station configures the ARI according to the determined HARQ response method (S1220). The base station configures the ARI to indicate a transmission resource of PUCCH format 3 to be used by the terminal. When the SORTD is applied, a plurality of transmission resources may be allocated through the ARI according to the transmission antenna to which the SORTD is applied in the terminal.

The base station transmits the configured ARI through the downlink control channel (S1230). The ARI is transmitted using the TPC field of the PDCCH. Which subframe is to be transmitted, whether to transmit the ARI fixedly, according to a certain period, whether to transmit the ARI in a subframe of DAI ≠ 0 according to a specific rule, as previously described, Follow the method.

The base station receives a HARQ response transmitted by the terminal according to the determined HARQ response scheme as a transmission resource allocated through the ARI (S1240).

13 is a flowchart schematically illustrating an operation of a terminal in a TDD system using a single carrier, to which the present invention is applied.

The terminal receives downlink subframes (S1310).

The UE acquires the ARI transmitted on the control channel in the received downlink subframe (S1320).

The terminal may acquire the ARI in a predetermined subframe according to a method predetermined in the base station.

The terminal receives a transmission resource of PUCCH format 3 through the received ARI (S1330). The terminal is allocated a transmission resource indicated by the ARI on the ARI mapping table.

The terminal transmits an HARQ response by using the allocated transmission resource (S1340). When a transmission resource of PUCCH format 3 is allocated through ARI, the UE may multiplex and transmit HARQ response signals of up to 20 bits.

14 is a flowchart schematically illustrating an operation of a terminal when a contrast mode is applied according to the present invention.

Referring to FIG. 14, the terminal determines whether an ARI for allocating resources is received in a normal mode (S1410).

If the ARI is received, a transmission resource indicated by the received ARI may be allocated (S1420).

If ARI is not received, contrast mode may be applied.

When the terminal does not receive the ARI, that is, in the contrast mode, the terminal may determine whether SORTD is applied (S1430). Depending on whether SORTD is applied, the number of transmission resources to be obtained may vary.

When SORTD is applied, the terminal may acquire a plurality of transmission resources (S1440).

If SORTD is not applied and a single antenna is used, the terminal may acquire one transmission resource (S1450).

In this case, the transmission resource may be allocated implicitly or explicitly.

The UE may determine whether a plurality of downlink subframes have been transmitted (S1660). When a plurality of downlink subframes are received and the payload size of the HARQ ACK / NACK signal to be transmitted increases, bundling may be required.

Subsequently, the terminal may transmit the HARQ ACK / NACK signal using the contrast mode (S1480).

15 is a block diagram schematically illustrating an example of a configuration of a base station and a terminal in a system to which the present invention is applied.

The terminal 1500 may include a transceiver 1510, a storage 1520, and a controller 1530. The base station 1540 may include a transceiver 1550, a storage 1560, and a controller 1570.

The terminal 1500 transmits and receives necessary information through the transceiver 1510. The transceiver 1510 may include multiple antennas, in which case the terminal 1500 may apply SORTD.

The storage unit 1520 stores information necessary for the terminal 1500 to perform wireless communication on a network. For example, the storage unit 1520 may configure an uplink-downlink (UL-DL) between a base station and a terminal, an ARI mapping table, an ARI transmission subframe, a priority between ARI windows, and a TPC transmitted in a corresponding downlink subframe. Information on whether an ARI or a TPC command is transmitted may be stored in the field, and control information transmitted through RRC signaling may be stored. When allocating transmission resources to the ARI and applying the SORTD, the storage unit 1520 may store an ARI mapping table that allocates the transmission resources according to the number of transmission antennas to which the SORTD is applied. In addition, the storage unit 1520 may store settings of a normal mode and a contrast mode for HARQ ACK / NACK signal transmission.

The controller 1530 may be connected to the transceiver 1510 and the storage 1520 to control them. The controller 1530 may transmit a HARQ ACK / NACK signal to the base station through the transceiver 1510 in an uplink subframe to which the resource is allocated by using the resource determined by the resource determiner 1540.

When using the PUCCH format 3 resources for HARQ ACK / NACK signal transmission, the control unit 1530 acquires the resources of the PUCCH format 3 indicated by the received ARI on the ARI mapping table stored in the storage unit 1520 and transmits the HARQ ACK. The resource to be used for transmitting the / NACK signal can be determined. When using the resources of the PUCCH format 1a / 1b for transmitting HARQ ACK / NACK signal, the controller 1530 acquires the resources of the PUCCH format 1a / 1b based on the first CCE of the PDCCH received on the downlink subframe The resource to be used for transmitting the HARQ ACK / NACK signal can be determined. When a resource is explicitly allocated through RRC signaling or the like, the controller 1530 may acquire the allocated resource and determine a resource to be used for transmitting an ACK / NACK signal.

In addition, the controller 1530 may determine whether the normal mode may be applied, and when the normal mode cannot be applied to the HARQ ACK / NACK signal transmission, the controller 1530 may determine to apply the contrast mode and perform a necessary procedure.

The base station 1540 may transmit and receive necessary information through the transceiver 1550. The transceiver 1550 may include multiple antennas and support SORTD.

The storage unit 1560 stores information necessary for the base station 1540 to perform wireless communication on the network. For example, the storage unit 1560 may include a downlink-uplink configuration, an ARI mapping table, an ARI transmission subframe, a priority between the ARI windows, and a TPC transmitted in the corresponding downlink subframe, which may be preset between the base station and the terminal. Information on whether an ARI is transmitted or a TPC command may be stored in the field, and control information transmitted through RRC signaling may be stored.

The controller 1570 may be connected to the transceiver 1550 and the storage 1560 to control them. The controller 1570 may transmit information regarding allocation of HARQ ACK / NACK resources such as ARI to the terminal through the transceiver 1550. The controller 1570 may allow the ARI to be transmitted using the TPC field transmitted on the PDCCH of the downlink subframe. In addition, the controller 1570 may transmit the RRC signaling related to resource allocation to the terminal through the transceiver 1550.

The controller 1570 may determine whether to use PUCCH format 1a / 1b or PUCCH format 3 for an uplink subframe associated with a downlink subframe to be transmitted.

The controller 1570 may allocate a resource used to transmit the HARQ ACK / NACK signal on the PUCCH according to the PUCCH format. If it is determined that the PUCCH format 3 is to be used, the controller 1570 may configure an ARI used to allocate a resource of the PUCCH format 3.

The controller 1570 may also determine whether to apply the SORTD. If it is determined to apply the SORTD, the controller 1570 may configure an ARI mapping table and an ARI for applying the SORTD.

In the exemplary system described above, the methods are described based on a flowchart as a series of steps or blocks, but the invention is not limited to the order of steps, and certain steps may occur in a different order or concurrently with other steps than those described above. Can be. In addition, those skilled in the art will appreciate that the steps shown in the flowcharts are not exclusive and that other steps may be included or one or more steps in the flowcharts may be deleted without affecting the scope of the present invention.

The above-described embodiments include examples of various aspects. While not all possible combinations may be described to represent the various aspects, one of ordinary skill in the art will recognize that other combinations are possible. Accordingly, the invention is intended to embrace all other replacements, modifications and variations that fall within the scope of the following claims.

Claims (20)

In a time division duplex (TDD) system using a single carrier,
On the resource mapping table composed of resources of Physical Uplink Control Channel (PUCCH) format 3, a transmission resource indicated by an ACK (Ack / nack Resource Indicator) is allocated as a transmission resource to be used for transmission of the PUCCH,
The ARI is transmitted to the terminal using a transmit power control (TPC) field transmitted on a physical downlink control channel (PDCCH),
The resource mapping table is a resource allocation method of a base station characterized in that the same number of transmission resources as the number of transmission antennas of the terminal is allocated by the ARI. The method of claim 1, wherein the resource mapping table is delivered to the terminal through higher layer signaling. The method of claim 1, wherein the UE implicitly allocates a transmission resource for transmitting PUCCH when the downlink subframe in which the ARI is transmitted is missing. The TPC field of a downlink subframe having a Downlink Assignment Indicator (DAI) value of 0 is used to transmit a TPC command.
The TPC field of a downlink subframe whose DAI value is not 0 is used for transmitting an ARI. The method of claim 4, wherein the current uplink transmission power is maintained when the downlink subframe transmitting the power control command is lost. In a time division duplex (TDD) system using a single carrier,
Acquire a transmission resource indicated by an ACK (Ack / nack Resource Indicator) on a resource mapping table composed of resources of Physical Uplink Control Channel (PUCCH) format 3 as a transmission resource for transmission of the PUCCH,
By using the obtained transmission resources to transmit a HARQ (Hybrid Automatic Repeat reQuest) response signal to the base station,
The ARI is transmitted from a base station using a transmit power control (TPC) field transmitted on a physical downlink control channel (PDCCH),
The resource mapping table is a method of transmitting a HARQ response signal of a terminal, characterized in that the same number of transmission resources as the number of transmission antennas of the terminal is allocated by the ARI. The method of claim 6, wherein the terminal transmits a HARQ ACK / NACK signal by applying SORTD (Spatial Orthogonal Resource Transmit Diversity). The method of claim 6, wherein the resource mapping table is transmitted from a base station through higher layer signaling. The HARQ response signal of claim 6, wherein when the ARI is not received, a transmission resource to be used for the transmission of the PDCCH is implicitly allocated based on the control channel element (CCE) of the received PUCCH. Transmission method. 10. The method of claim 9, wherein the HARQ response signal is transmitted by bundling the HARQ response signal in a time domain by using the implicitly allocated transmission resource. The method of claim 9, wherein the HARQ response signal is transmitted using the channel selection using the implicitly allocated transmission resource. The method of claim 9, wherein the same number of transmission resources as the number of transmission antennas of the terminal is implicitly allocated, and the terminal transmits a HARQ response signal by applying SORTD to the implicitly allocated transmission resources. HARQ response signal transmission method of the terminal. The method of claim 6, wherein a TPC command is obtained from a TPC field of a downlink subframe having a downlink assignment indicator (DAI) value of 0,
The method of transmitting HARQ response signal of a terminal, characterized in that to obtain an ARI from a TPC field of a downlink subframe whose DAI value is not zero. The method of claim 13, wherein the PUCCH transmission is performed using the currently set uplink transmission power when the power control command is not received. 10. The method of claim 6, if the ARI is not received, when dynamic scheduling is applied, resources are allocated based on a control channel element index on a control channel in a received downlink subframe, and static scheduling is performed. If applied, the resource indicated by the resource allocation indicator transmitted on the downlink control channel with the static scheduling is activated,
The allocated resource is a method of transmitting a HARQ signal, characterized in that the PUCCH format 1a or PUCCH format 1b. Transmitting and receiving unit for transmitting and receiving a signal; And
It includes a control unit for allocating the transmission resources of the terminal,
The control unit,
On the resource mapping table composed of resources of Physical Uplink Control Channel (PUCCH) format 3, a transmission resource indicated by an ACK (Ack / nack Resource Indicator) is allocated as a transmission resource to be used for transmission of the PUCCH,
Transmitting the ARI to the terminal using a transmit power control (TPC) field transmitted on a physical downlink control channel (PDCCH),
Configure the resource mapping table so that the same number of transmission resources as the number of transmission antennas of the terminal are allocated by the ARI,
A TPC field of a downlink subframe having a Downlink Assignment Indicator (DAI) value of 0 is used for transmission of a power control command.
A base station, characterized in that the TPC field of a downlink subframe whose DAI value is not 0 is used for transmission of an ARI. 17. The device station of claim 16, wherein the control unit maintains current uplink transmission power when a downlink subframe that transmits the power control command is lost. Transmitting and receiving unit for transmitting and receiving a signal; And
It includes a control unit for controlling the transmission of the hybrid automatic repeat reQuest (HARQ) response signal,
The control unit,
Acquire a transmission resource indicated by an ACK (Ack / nack Resource Indicator) on a resource mapping table composed of resources of Physical Uplink Control Channel (PUCCH) format 3 as a transmission resource to be used for transmission of the PUCCH,
The HARQ response signal is transmitted to the base station using the obtained transmission resource,
The ARI is transmitted from a base station through a transmit power control (TPC) field transmitted on a physical downlink control channel (PDCCH),
The resource mapping table is a terminal, characterized in that configured to be allocated by the ARI the same number of transmission resources as the number of transmit antennas of the terminal. The method of claim 18, wherein the control unit
A TPC command is obtained from a TPC field of a downlink subframe having a Downlink Assignment Indicator (DAI) value of 0.
UE, characterized in that to obtain an ARI from the TPC field of the downlink subframe whose DAI value is not zero. The method of claim 18, wherein the control unit,
If the power control command is not received, the terminal characterized in that to perform PUCCH transmission at the currently set uplink transmission power.

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