KR102490617B1 - Method and apparatus for transmitting and receiving uplink control channel in communication system - Google Patents

Abstract

A method and apparatus for transmitting and receiving an uplink control channel in a communication system are disclosed. A method of operating a terminal includes receiving a downlink data channel from a base station in slot #n or slot #(n-l), using a slot format indicator indicating the format of slot #(n+k) in which uplink control information is transmitted. Receiving from the base station in slot #n, and transmitting the uplink control information including an HARQ response for the downlink data channel to the base station in slot #(n+k). Accordingly, the performance of the communication system can be improved.

Description

Method and apparatus for transmitting and receiving an uplink control channel in a communication system

The present invention relates to a wireless communication technology, and more particularly, to a technology for transmitting and receiving an uplink control channel in a communication system.

A communication system may include a core network, a base station, a terminal, and the like. When downlink transmission is performed in a communication system, a base station may transmit downlink signals (eg, control information, data, and reference signals) to a terminal. When uplink transmission is performed in a communication system, the terminal may transmit uplink signals (eg, control information, data, reference signals) to the base station.

Control information transmitted from the base station to the terminal may be referred to as downlink control information (DCI), and control information transmitted from the terminal to the base station may be referred to as uplink control information (UCI). The UCI may include at least one of a scheduling request (SR), channel state information, and a hybrid automatic repeat request (HARQ) response.

On the other hand, since the 5G communication system (eg, new radio (NR) system) supports dynamic time division duplex (TDD), beam-centric communication or low-latency communication, The number of uplink symbols allowed for UCI transmission in may be variable. The number of uplink symbols allowed for UCI transmission may be limited. For example, when there is a lot of downlink data, the number of uplink symbols allowed for UCI transmission may be relatively small. Accordingly, a technique for transmitting and receiving an uplink control channel to support a case in which the number of downlink symbols allowed for UCI transmission is variable is required.

An object of the present invention to solve the above problems is to provide a method and apparatus for transmitting and receiving an uplink control channel in a communication system.

A method of operating a terminal according to a first embodiment of the present invention for achieving the above object includes receiving a downlink data channel from a base station in slot #n or slot #(n-l), a slot in which uplink control information is transmitted. Receiving a slot format indicator indicating a format of #(n+k) from the base station in the slot #n, and the uplink control information including the HARQ response for the downlink data channel in the slot #( n+k), wherein n and k are each an integer greater than or equal to 0, and l is an integer greater than or equal to 1.

Here, the slot format indicator indicates formats of slots #(n+k) to #(n+k+j), and j may be an integer greater than or equal to 1.

Here, format indicators for two or more different slots may be transmitted in the slot #n, and one slot format indicator among the two or more different slot format indicators is the format of the slot #(n+k). , and the remaining slot format indicators may indicate the format of the slot #(n+k) and subsequent slots.

Here, two or more different slot format indicators may be transmitted in the slot #n, and one slot format indicator among the two or more different slot format indicators indicates the format of the slot #(n+k). The remaining slot format indicators may be slot format indicators transmitted through slots preceding slot #n, and the remaining slot format indicators may indicate formats of slots other than slot #(n+k). can

Here, the slot format indicator may indicate the number of one or more symbols used for transmission of at least the uplink control information in the slot #(n+k).

Here, the slot format indicator may be received through the common control channel of the slot #n.

Here, the time interval between the slot #n and the slot #(n+k) may be a minimum time required to generate the HARQ response for the downlink data channel.

To achieve the above object, a method of operating a terminal according to a second embodiment of the present invention includes receiving a downlink data channel from a base station in slot #n, slot #(n+l) to slot #(n+l). +k) repeatedly transmitting the uplink data channel to the base station k times, and a HARQ response for the downlink data channel in slot #(n+m) to slot #(n+m+k') and repeatedly transmitting uplink control information k′ times, wherein each of n, l and m is an integer greater than or equal to 0, each of k and k′ is an integer greater than or equal to 1, and the uplink data channel in at least one slot and the uplink control information are simultaneously transmitted.

Here, when the uplink data channel and the uplink control information are simultaneously transmitted in the at least one slot, the uplink control information may be transmitted through the uplink data channel instead of the uplink control channel.

Here, the uplink control information may be transmitted through a punctured RE among REs configured for the uplink data channel.

Here, when the uplink control information is mapped to one or more REs configured for the uplink data channel, uplink data is mapped to one or more REs configured for the uplink data channel, among the REs configured for the uplink data channel. may be mapped to the remaining REs except for , and when an RE mapping operation is performed, a rate matching operation for the uplink data may be performed.

Here, among the slots #(n+l) to the slots #(n+m+k'), there are p slots including undecided symbols, and the undecided symbols correspond to the uplink data channel or the uplink control information. When overlapping with resources used for transmission, the uplink data channel and the uplink control information may not be transmitted through the p slots, and the uplink data channel may be transmitted through the slots #(n+l) to It can be repeatedly transmitted k times in slot #(n+l+k+p), and the uplink control information is k' in slot #(n+m) to slot #(n+m+k'+p). It can be transmitted repeatedly, and p can be an integer greater than 1.

Here, among the slots #(n+l) to the slots #(n+m+k'), there are p slots including undecided symbols, and the undecided symbols correspond to the uplink data channel or the uplink control information. When overlapping with resources used for transmission, the uplink data channel and the uplink control information may not be transmitted through the p slots, and the uplink data channel may be transmitted through the slots #(n+l) to It may be repeatedly transmitted (k-p) times in slot #(n+l+k), and the uplink control information is transmitted in slot #(n+m) to slot #(n+m+k') (k It can be repeatedly transmitted '-p) times, and p can be an integer of 1 or more.

Here, the number of repetitions (k) of the uplink data channel and the number of repetitions (k') of the uplink control information may be set through at least one of a higher layer signaling procedure and a DCI transmission procedure.

To achieve the above object, a method of operating a terminal according to a third embodiment of the present invention includes receiving a downlink data channel from a base station in slot #n, slot #(n+l) to slot #(n+l). +k) repeatedly transmitting uplink control information including an HARQ response for the downlink data channel to the base station k times, and slot #(n+m) to slot #(n+m+k') and repeatedly transmitting an uplink data channel k' times, where n is an integer greater than or equal to 0, each of l and m is an integer greater than or equal to 1, each of k and k' is an integer greater than or equal to 2, and in at least one slot The uplink control information and the uplink data channel are simultaneously transmitted.

Here, when the uplink control information and the uplink data channel are simultaneously transmitted in the at least one slot, the uplink control information may be transmitted through the uplink data channel instead of the uplink control channel.

Here, the uplink control information may be transmitted through a punctured RE among REs configured for the uplink data channel.

Here, when the uplink control information is mapped to one or more REs configured for the uplink data channel, uplink data is mapped to one or more REs configured for the uplink data channel, among the REs configured for the uplink data channel. may be mapped to the remaining REs except for , and when an RE mapping operation is performed, a rate matching operation for the uplink data may be performed.

Here, among the slots #(n+l) to the slots #(n+m+k'), there are p slots including undecided symbols, and the undecided symbols correspond to the uplink data channel or the uplink control information. When overlapping with resources used for transmission, the uplink control information and the uplink data channel may not be transmitted through the p slots, and the uplink control information is transmitted through the slots #(n+l) to It can be repeatedly transmitted k times in slot # (n + l + k + p), and the uplink data channel is k' in slot # (n + m) to slot # (n + m + k' + p). It can be transmitted repeatedly, and p can be an integer greater than 1.

Here, among the slots #(n+l) to the slots #(n+m+k'), there are p slots including undecided symbols, and the undecided symbols correspond to the uplink data channel or the uplink control information. When overlapping with resources used for transmission, the uplink control information and the uplink data channel may not be transmitted through the p slots, and the uplink control information is transmitted through the slots #(n+l) to It may be repeatedly transmitted (k-p) times in the slot #(n + l + k), and the uplink data channel is transmitted in the slot # (n + m) to the slot # (n + m + k') (k It can be repeatedly transmitted '-p) times, and p can be an integer of 1 or more.

According to the present invention, L1 control information can be transmitted through a resource configured for a downlink data channel. In this case, L1 control information may be mapped to REs adjacent to the DM-RS. Therefore, a reception error of the L1 control information can be minimized, and a frequency multiplexing gain for the L1 control information can be obtained.

In addition, the base station may transmit a preemption indicator indicating that the downlink data channel #2 for the second terminal is transmitted through a preset resource among resources configured for the downlink data channel #1 for the first terminal. The terminal may generate an HARQ response for downlink data channel #1 based on the preemption indicator and transmit the generated HARQ response to the base station. Accordingly, a resource usage rate may be improved and an error for an HARQ response may be reduced.

In addition, the terminal may receive downlink data channels #1 and #2, and may repeatedly transmit HARQ response #1 for downlink data channel #1 and HARQ response #2 for downlink data channel #2, respectively. . HARQ responses #1 and #2 may be simultaneously transmitted through the same slot. Accordingly, reception errors of HARQ responses may be reduced.

1 is a conceptual diagram illustrating a first embodiment of a communication system.
2 is a block diagram showing a first embodiment of a communication node constituting a communication system.
3 is a block diagram illustrating a first embodiment of a TB in a communication system.
4 is a block diagram illustrating a second embodiment of a TB in a communication system.
5 is a block diagram illustrating a third embodiment of a TB in a communication system.
6A is a conceptual diagram illustrating a first embodiment of a method for mapping L1 control information.
6B is a conceptual diagram illustrating a second embodiment of a method for mapping L1 control information.
7A is a conceptual diagram illustrating a third embodiment of a method for mapping L1 control information.
7B is a conceptual diagram illustrating a fourth embodiment of a mapping method of L1 control information.
8 is a conceptual diagram illustrating a first embodiment of a data channel.
9 is a conceptual diagram illustrating a first embodiment of an HARQ response in a communication system supporting CC.
10 is a conceptual diagram illustrating a first embodiment of a HARQ response codebook in a communication system supporting CC.
11 is a conceptual diagram illustrating a second embodiment of an HARQ response codebook in a communication system supporting CC.
12A is a timing diagram illustrating a first embodiment of a method of transmitting uplink control information.
12B is a timing diagram illustrating a second embodiment of a method of transmitting uplink control information.
13 is a timing diagram illustrating a first embodiment of HARQ response transmission in a communication system.
14A is a timing diagram illustrating a first embodiment of a method of transmitting an uplink channel in a communication system.
14B is a timing diagram illustrating a second embodiment of a method of transmitting an uplink channel in a communication system.
15A is a timing diagram illustrating a third embodiment of a method of transmitting an uplink channel in a communication system.
15B is a timing diagram illustrating a fourth embodiment of a method of transmitting an uplink channel in a communication system.
15C is a timing diagram illustrating a fifth embodiment of a method of transmitting an uplink channel in a communication system.
16A is a timing diagram illustrating a first embodiment of a method of transmitting an uplink control/data channel in a communication system.
16B is a timing diagram illustrating a second embodiment of a method of transmitting an uplink control/data channel in a communication system.
16C is a timing diagram illustrating a third embodiment of a method of transmitting an uplink control/data channel in a communication system.
16D is a timing diagram illustrating a fourth embodiment of a method of transmitting an uplink control/data channel in a communication system.
17A is a timing diagram illustrating a fifth embodiment of a method for transmitting an uplink control/data channel in a communication system.
17B is a timing diagram illustrating a sixth embodiment of a method for transmitting an uplink control/data channel in a communication system.
17C is a timing diagram illustrating a seventh embodiment of a method of transmitting an uplink control/data channel in a communication system.
17D is a timing diagram illustrating an eighth embodiment of a method for transmitting an uplink control/data channel in a communication system.
18 is a timing diagram illustrating a ninth embodiment of a method for transmitting an uplink control/data channel in a communication system.
19 is a timing diagram illustrating a sixth embodiment of a method of transmitting an uplink channel in a communication system.

Since the present invention can make various changes and have various embodiments, specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the present invention to specific embodiments, and should be understood to include all modifications, equivalents, or substitutes included in the spirit and technical scope of the present invention.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. These terms are only used for the purpose of distinguishing one component from another. For example, a first element may be termed a second element, and similarly, a second element may be termed a first element, without departing from the scope of the present invention. The terms and/or include any combination of a plurality of related recited items or any of a plurality of related recited items.

It is understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, but other elements may exist in the middle. It should be. On the other hand, when an element is referred to as “directly connected” or “directly connected” to another element, it should be understood that no other element exists in the middle.

Terms used in this application are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, the terms "include" or "have" are intended to designate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, but one or more other features It should be understood that the presence or addition of numbers, steps, operations, components, parts, or combinations thereof is not precluded.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and unless explicitly defined in the present application, they should not be interpreted in an ideal or excessively formal meaning. don't

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention will be described in more detail. In order to facilitate overall understanding in the description of the present invention, the same reference numerals are used for the same components in the drawings, and redundant descriptions of the same components are omitted.

A communication system to which embodiments according to the present invention are applied will be described. A communication system to which embodiments according to the present invention are applied is not limited to the contents described below, and embodiments according to the present invention can be applied to various communication systems. Here, the communication system may be used in the same sense as a communication network.

1 is a conceptual diagram illustrating a first embodiment of a communication system.

Referring to FIG. 1, a communication system 100 includes a plurality of communication nodes 110-1, 110-2, 110-3, 120-1, 120-2, 130-1, 130-2, 130-3, 130-4, 130-5, 130-6). In addition, the communication system 100 includes a core network (eg, a serving-gateway (S-GW), a packet data network (PDN)-gateway (P-GW), and a mobility management entity (MME)). can include more. When the communication system 100 is a 5G communication system (eg, a new radio (NR) system), the core network includes an access and mobility management function (AMF), a user plane function (UPF), a session management function (SMF), and the like. can include

A plurality of communication nodes may support 4G communication (eg, long term evolution (LTE), advanced (LTE-A)), 5G communication, and the like specified in the 3rd generation partnership project (3GPP) standard. 4G communication may be performed in a frequency band of 6 GHz or less, and 5G communication may be performed in a frequency band of 6 GHz or more as well as a frequency band of 6 GHz or less. For example, for 4G communication and 5G communication, a plurality of communication nodes may use a code division multiple access (CDMA)-based communication protocol, a wideband CDMA (WCDMA)-based communication protocol, a time division multiple access (TDMA)-based communication protocol, FDMA (frequency division multiple access)-based communication protocol, OFDM (orthogonal frequency division multiplexing)-based communication protocol, Filtered OFDM-based communication protocol, CP (cyclic prefix)-OFDM-based communication protocol, DFT-s-OFDM (discrete Fourier transform-spread-OFDM) based communication protocol, OFDMA (orthogonal frequency division multiple access) based communication protocol, SC (single carrier)-FDMA based communication protocol, NOMA (Non-orthogonal multiple access), GFDM (generalized frequency) division multiplexing)-based communication protocol, FBMC (filter bank multi-carrier)-based communication protocol, UFMC (universal filtered multi-carrier)-based communication protocol, SDMA (Space Division Multiple Access)-based communication protocol, etc. can be supported. . Each of the plurality of communication nodes may have the following structure.

2 is a block diagram showing a first embodiment of a communication node constituting a communication system.

Referring to FIG. 2 , a communication node 200 may include at least one processor 210, a memory 220, and a transceiver 230 connected to a network to perform communication. In addition, the communication node 200 may further include an input interface device 240, an output interface device 250, a storage device 260, and the like. Each component included in the communication node 200 may be connected by a bus 270 to communicate with each other.

However, each component included in the communication node 200 may be connected through an individual interface or an individual bus centered on the processor 210 instead of the common bus 270 . For example, the processor 210 may be connected to at least one of the memory 220, the transmission/reception device 230, the input interface device 240, the output interface device 250, and the storage device 260 through a dedicated interface. .

The processor 210 may execute a program command stored in at least one of the memory 220 and the storage device 260 . The processor 210 may refer to a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which methods according to embodiments of the present invention are performed. Each of the memory 220 and the storage device 260 may include at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory 220 may include at least one of a read only memory (ROM) and a random access memory (RAM).

Referring back to FIG. 1, the communication system 100 includes a plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2), a plurality of terminals 130- 1, 130-2, 130-3, 130-4, 130-5, 130-6). Base stations 110-1, 110-2, 110-3, 120-1, and 120-2 and terminals 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6 The inclusive communication system 100 may be referred to as an “access network”. Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 may form a macro cell. Each of the fourth base station 120-1 and the fifth base station 120-2 may form a small cell. The fourth base station 120-1, the third terminal 130-3, and the fourth terminal 130-4 may belong to the cell coverage of the first base station 110-1. The second terminal 130-2, the fourth terminal 130-4, and the fifth terminal 130-5 may belong to the cell coverage of the second base station 110-2. The fifth base station 120-2, the fourth terminal 130-4, the fifth terminal 130-5, and the sixth terminal 130-6 may belong to the cell coverage of the third base station 110-3. there is. The first terminal 130-1 may belong to the cell coverage of the fourth base station 120-1. The sixth terminal 130-6 may belong to the cell coverage of the fifth base station 120-2.

Here, each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 is a NodeB, an evolved NodeB, a gNB, and an advanced base station (ABS). ), high reliability-base station (HR-BS), base transceiver station (BTS), radio base station, radio access station (RAS), radio transceiver, access point, access It may be referred to as a node, a relay, an advanced relay station (ARS), a high reliability-relay station (HR-RS), and the like. Each of the plurality of terminals 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6 is a UE (user equipment), terminal, access terminal, mobile It may be referred to as a mobile terminal, station, subscriber station, mobile station, portable subscriber station, node, device, and the like.

Meanwhile, each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may operate in different frequency bands or may operate in the same frequency band. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be connected to each other through an ideal backhaul link or a non-ideal backhaul link, and , information can be exchanged with each other through an ideal backhaul link or a non-ideal backhaul link. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be connected to the core network through an ideal backhaul link or a non-ideal backhaul link. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 transmits a signal received from the core network to a corresponding terminal 130-1, 130-2, 130-3, and 130 -4, 130-5, 130-6), and signals received from corresponding terminals 130-1, 130-2, 130-3, 130-4, 130-5, 130-6 are transmitted to the core network can be sent to

In addition, each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 transmits MIMO (eg, single user (SU)-MIMO, multi-user (MU)- MIMO, massive MIMO, etc.), CoMP (coordinated multipoint) transmission, CA (carrier aggregation) transmission, transmission in an unlicensed band, device to device communication (D2D) (or ProSe ( proximity services)) may be supported. Here, each of the plurality of terminals 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6 is a base station 110-1, 110-2, 110-3, 120-1 , 120-2) and operations supported by the base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be performed. For example, the second base station 110-2 can transmit a signal to the fourth terminal 130-4 based on the SU-MIMO scheme, and the fourth terminal 130-4 uses the SU-MIMO scheme. A signal may be received from the second base station 110-2. Alternatively, the second base station 110-2 may transmit a signal to the fourth terminal 130-4 and the fifth terminal 130-5 based on the MU-MIMO scheme, and the fourth terminal 130-4 And each of the fifth terminal 130-5 may receive a signal from the second base station 110-2 by the MU-MIMO method.

Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 may transmit a signal to the fourth terminal 130-4 based on the CoMP scheme, and The terminal 130-4 may receive signals from the first base station 110-1, the second base station 110-2, and the third base station 110-3 by CoMP. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 includes a terminal 130-1, 130-2, 130-3, and 130-4 belonging to its own cell coverage. , 130-5, 130-6) and a CA method. Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 controls D2D between the fourth terminal 130-4 and the fifth terminal 130-5. and each of the fourth terminal 130-4 and the fifth terminal 130-5 may perform D2D under the control of the second base station 110-2 and the third base station 110-3, respectively. .

Next, methods for transmitting and receiving an uplink control channel in a communication system will be described. Even when a method (for example, transmission or reception of a signal) performed in a first communication node among communication nodes is described, a second communication node corresponding thereto is described as a method performed in the first communication node and a method (eg, signal transmission or reception) For example, receiving or transmitting a signal) may be performed. That is, when the operation of the terminal is described, the corresponding base station may perform an operation corresponding to the operation of the terminal. Conversely, when the operation of the base station is described, a terminal corresponding thereto may perform an operation corresponding to the operation of the base station.

An NR system can support dual connectivity (DC) and carrier aggregation (CA) by operating one or more carriers. A physical channel on which a hybrid automatic repeat request (HARQ) response is transmitted when a plurality of carriers are operated and a physical channel on which a HARQ response is transmitted when one carrier is operated may be set as follows. Here, the HARQ response may be an acknowledgment (ACK), a negative ACK (NACK), or the like.

In the NR system, communication may be performed in units of transport blocks (TBs), and an encoded TB may be referred to as a codeword (CW). For example, the base station can transmit CW to the terminal, and the terminal can receive the CW from the base station. When MIMO is used, the base station may transmit one or more CWs to the terminal. The UE may generate one HARQ response for each received CW.

When communication between the base station and the terminal is performed using one carrier, the terminal may generate an HARQ response having a size of 1 bit or 2 bits. When communication between the base station and the terminal is performed using a plurality of carriers, the terminal may generate an encoded HARQ response by encoding the HARQ response for the plurality of carriers. The base station uses a "higher layer signaling procedure (eg, a radio resource control (RRC) signaling procedure)" or a "combination of a higher layer signaling procedure and a downlink control information (DCI) transmission procedure" to transmit an HARQ response. resource information (eg, time-frequency resource information) may be notified to the terminal. Resource information used for transmission of the HARQ response may be a subframe index, a slot index, a sub-slot index, a mini-slot index, or a symbol index. . The terminal may transmit the HARQ response using the resource indicated by the base station.

Here, the HARQ response may be included in uplink control information, and the uplink control information may be transmitted through an uplink control channel (eg, physical uplink control channel (PUCCH)). An uplink control channel may consist of one or more symbols, and consecutive symbols may be referred to as "UL slot", "UL subslot" or "UL minislot". Also, an uplink control channel may consist of one or more UL slots, one or more UL subslots, or one or more UL minislots. The base station may configure an uplink control channel for the terminal using a higher layer signaling procedure. The terminal may transmit uplink control information using an uplink control channel. The uplink control information may include at least one of HARQ response, channel state information, and scheduling request (SR). In addition, the terminal may transmit a buffer status report (BSR) using an uplink control channel.

Meanwhile, when a first terminal receives downlink data channel #1 from a base station and a second terminal receives downlink data channel #2 from a base station, methods for transmitting and receiving an uplink control channel (eg, UCI) This can be done according to the examples below.

Downlink data channel #1 and downlink data channel #2 use the same time-frequency resource, and the priority of data belonging to downlink data channel #1 is lower than that of data belonging to downlink data channel #2. In this case, the base station may not transmit part or all of the downlink data channel #1 to the first terminal, and transmits the downlink data channel #2 using time-frequency resources not occupied by the downlink data channel #1. It can be transmitted to the second terminal. In this case, the base station provides information indicating that some or all of the resources configured for downlink data channel #1 are used for transmission of downlink data channel #2 (hereinafter referred to as "preemption indicator"). ) may be informed to the first terminal through the downlink control channel, and the first terminal may generate uplink control information based on information obtained through the downlink control channel. For example, UE 1 may check the time-frequency resource through which the downlink data channel #1 is transmitted based on the information obtained through the downlink control channel, and the downlink data received in the checked time-frequency resource. A HARQ response for channel #1 may be generated.

■ How to create TB and CBg (coded block group)

When downlink transmission is performed, the TB may be generated by a medium access control (MAC) layer of the base station, and when uplink transmission is performed, the TB may be generated by the MAC layer of the terminal.

3 is a block diagram illustrating a first embodiment of a TB in a communication system.

Referring to FIG. 3 , a TB 300 may include a MAC sub-header 310 and a MAC control element (CE) 320. TB 300 including MAC subheader 310 and MAC CE 320 may be referred to as a “Type-1 TB”. The MAC subheader 310 may be concatenated with the MAC CE 320. TB 300 may include a MAC header instead of MAC subheader 310 . That is, TB 300 may include a MAC header and MAC CE 320 .

4 is a block diagram illustrating a second embodiment of a TB in a communication system.

Referring to FIG. 4 , a TB 400 may include a MAC sub-header 410 and a MAC service data unit (SDU) 420. TB 400 including MAC subheader 410 and MAC SDU 420 may be referred to as a “Type-2 TB”. MAC subheader 410 may be concatenated with MAC SDU 420. TB 400 may include a MAC header instead of MAC subheader 410 . That is, TB 400 may include a MAC header and MAC SDU 420 .

Meanwhile, one TB may be segmented into a plurality of CBgs. CBg may contain one or more CBs. For example, the MAC layer can divide a TB into a plurality of CBgs, and can append a cyclic redundancy check (CRC) field to each CBg. CBg can be generated depending on the size of the TB. If the size of the TB is larger than a predefined size (eg, a size defined in 3GPP technical specification (TS)), the TB may be divided into one or more CBgs. Also, if necessary, filler bits may be attached to CBg. When the size of a TB is smaller than a predefined size (eg, a size defined in 3GPP TS), the corresponding TB may include one CBg. That is, one TB can be set to one CBg. In this case, a CRC field for TB may be generated instead of a CRC field for CBg.

Since the number of CBgs constituting the TB varies according to the size of the TB, the number of HARQ responses may also be variable. For example, when HARQ responses are generated for each CBg, the number of HARQ responses may increase as the number of CBgs increases. Since the UE can know the size of the TB based on the downlink scheduling information, it can know the number of HARQ responses for the corresponding TB. In a communication system supporting CA or time division duplex (TDD), a terminal may generate a plurality of HARQ responses according to a plurality of downlink scheduling information. The number of HARQ responses generated by the terminal may vary according to the number of discontinuous transmission (DTx).

Meanwhile, as another method of generating CBg, the base station may inform the terminal of the number of CBgs through a higher layer signaling procedure. In this case, the terminal may generate as many CBgs as the number of CBgs indicated by the base station. Therefore, the number of CBgs can be kept constant regardless of the size of TB, and since the number of CBgs is kept constant, the number of HARQ responses may not be changed. In order to keep the number of CBgs constant even when the sizes of TBs are different, the number of CBs belonging to CBg may vary. For example, when the size of TB is small, the number of CBs constituting one CBg may decrease, and when the size of TB is large, the number of CBs constituting one CBg may increase.

When the size of TB is small, the number of CBgs need not be large. Since the size of TB for system information is not large and system information is transmitted from the base station in a broadcast manner, a method for terminals to derive the same number of CBgs may be required. In this case, the number of CBgs may not be set by a higher layer signaling procedure. The base station can schedule a downlink data channel using a specific downlink control information format, and the terminal receiving the specific downlink control information format is configured according to the size of TB indicated by the specific downlink control information format. The number of CBgs can be determined. Therefore, the UE can generate as many CBgs as the number of CBgs determined by the specific downlink control information format.

The downlink (or uplink) data channel # 1 described above may be composed of one or more CBgs, and one or more CBgs belonging to the downlink (or uplink) data channel # 1 are downlink (or uplink) link) can be preempted by data channel #2. When a retransmission procedure for downlink (or uplink) data channel #1 is performed, a retransmission procedure for all or some CBgs belonging to downlink (or uplink) data channel #1 may be performed. When some CBgs belonging to downlink (or uplink) data channel #1 are retransmitted, the number of retransmitted CBgs may be greater than the number of CBgs preempted by downlink (or uplink) data channel #2. . When one CBg is mapped to resource elements (REs) of a plurality of minislots, even when downlink (or uplink) data channel #2 is transmitted through one minislot, downlink (or uplink) Link) This is because CBg belonging to data channel #1 can be mapped to a plurality of minislots.

Meanwhile, as another method of generating CBg, CBg may be generated based on an RE mapping method that considers not only the size of TB but also the boundary of a minislot. If CBg is created in units of "Type-1 TB", units of "Type-2 TB", or units of "Type-1 TB + Type-2 TB", CBg may be mapped to REs to fit the boundaries of minislots . In this case, the MAC layer can map one CBg to one or more minislots. Alternatively, the MAC layer may map multiple CBgs to one minislot. When the base station configures the minislot of the downlink (or uplink) data channel #2 with a relatively small number of symbols, CBg can be generated according to the minimum minislot unit (eg, 1 symbol unit) there is. Alternatively, CBg may be generated by considering a boundary of one or more minislots instead of a unit of minimum minislots. When CBg is generated in units of minimum minislots and only one terminal transmits and receives uplink (or downlink) data channel #2 with a base station using one symbol, other terminals belonging to the corresponding base station also use one symbol. CBg can be generated in units of symbols. To reduce this overhead, the MAC layer can map CBg to fit the boundaries of one or more minislots.

In order to improve the processing speed in the MAC layer of the receiving end and reduce the overhead of the soft buffer in the PHY layer of the receiving end, a separate MAC header may not be generated in the TB, and the TB is "type-1 TB" and "Type-2 TB". A method of generating a separate MAC header may be a method of attaching both CRC fields to each of TB and CBg belonging to the TB. In this case, since the MAC layer can report successful reception of a TB to a higher layer (e.g., Internet protocol (IP) layer) only when the CRC for the received TB is successful, the MAC layer has a CRC for CBgs Received signals can be stored in the soft buffer until all are successful. When retransmission is independently allowed for each CBg, a CBg with a successful CRC may be stored in a soft buffer. Since overhead increases when the CBg with successful CRC is stored in the soft buffer, the CBg with successful CRC may be reported to the MAC layer. To support this function, the CRC field for TB can be omitted and only the CRC field for CBg can be created.

A TB that does not include a separate MAC header may be created, and the TB may be divided into one or more CBgs. When a CBg with a successful CRC is reported to the MAC layer, the CBg with a successful CRC may not be stored in the soft buffer, and a retransmission procedure is performed in units of CBg until the CRC for the TB succeeds by receiving the MAC header. can The TB can be obtained by reconstructing the received CBg according to the order by the retransmission procedure.

A TB created according to the above-described embodiments may be as follows.

5 is a block diagram illustrating a third embodiment of a TB in a communication system.

Referring to FIG. 5 , a TB may include a plurality of MAC units. Each of the plurality of MAC units may be a “Type-1 TB” shown in FIG. 3 or a “Type-2 TB” shown in FIG. 4 . One MAC unit can contain one or more CBgs, and one CBg can be mapped to one or more minislots. In this case, one CBg may be mapped to an RE to fit the boundaries of one or more minislots. Also, CBg may be mapped within the scheduled bandwidth.

When the CRC field and MAC header for a TB are set, the CRC field of the TB can be located in the first or last region within the TB, and the MAC header of the TB is located in the first or last region within the TB. can be located The CRC field of TB can be derived by MAC header and payload.

■ Transmission method of control information

The base station may transmit a downlink data channel using MAC CE to deliver control information used in the MAC layer. In addition, the terminal may transmit an uplink data channel using MAC CE to deliver control information used in the MAC layer. Control information may belong to TB and may be involved in generating CBg. On the other hand, transmission resources for control information used in the physical layer may be allocated by a scheduler instead of the MAC layer of the base station. Accordingly, control information used in the physical layer may be transmitted through a downlink control channel or an uplink control channel.

When the transmission capacity of the control channel is limited and the amount of control information is large, the control information used in the physical layer may be transmitted through the data channel. Therefore, it may be necessary to define control information transmitted through the data channel without involvement of the MAC layer. For example, control information transmitted through a data channel without involvement of a MAC layer includes activation/deactivation information of an aperiodic channel state information-reference signal (CSI-RS), management information of beam correspondence, and band part. (bandwidth part) activation/deactivation information, PRB (physical resource block) bundle size of downlink control channel, resource information for interference measurement, RSRP of virtual sector (eg, beam) (reference signal received power), CSI (eg, CQI (channel quality indicator), PMI (precoding matrix indicator), RI (rank indicator), CRI (CSI-RS resource indicator), etc.) there is. This control information may be referred to as "L1 control information", and a plurality of "downlink control information types" may be defined according to the type of L1 control information included in the downlink control information, and included in the uplink control information. A plurality of "uplink control information types" may be defined according to the type of L1 control information to be used. In addition, in the following embodiments, L1 control information may be used in the same meaning as a downlink control information type (or uplink control information type). For example, the L1 control information may indicate a downlink control information type or an uplink control information type, and the downlink control information type or uplink control information type may indicate L1 control information.

When a resource allocation operation for the UE is performed, the scheduler of the base station may inform the UE of resource information occupied by TBs or CBgs for a data channel using downlink control information. In addition, the scheduler of the base station may allocate resources for transmission of L1 control information within the resources for the data channel, and inform the terminal of resource information allocated for the L1 control information. Alternatively, the base station may transmit the downlink control information type to the terminal without resource allocation of a data channel for the terminal, and may request transmission of the uplink control information type to the terminal.

A modulation order and code rate for L1 control information may be defined in the 3GPP TS. Alternatively, the base station may transmit downlink control information indicating a modulation order and a coding rate for L1 control information to the terminal. For example, the modulation order of the L1 control information may be quadrature phase shift keying (QPSK), and the coding rate of the L1 control information is a relative offset from the coding rate of the data channel scheduled by the downlink control information. can be directed.

The base station may inform the terminal of the downlink control information type (or uplink control information type) together with the resource allocation information of the data channel using the downlink control information. The size of L1 control information may be defined in 3GPP TS. Alternatively, the base station may inform the terminal of the size of the L1 control information through a higher layer signaling procedure. Therefore, the UE allocates L1 control information within the resources configured for the data channel based on the type of L1 control information identified by the downlink control information type or uplink control information type, the modulation order and coding rate of the L1 control information, and the like. resources can be checked. In this case, the UE may perform an RE demapping operation for the downlink control information type in the identified resource, and may perform a RE mapping operation for the uplink control information type in the identified resource. The RE mapping operation and rate matching operation for the data channel may be performed based on resources not occupied by the L1 control information among resources allocated for the data channel.

When the L1 control information is mapped to the RE along with the data channel, a method for minimizing errors in the base station or terminal will be required. In order to minimize reception error of L1 control information, as in the following embodiments, L1 control information may be mapped near an RS (eg, demodulation-reference signal (DM-RS)) to obtain a frequency multiplexing gain.

6A is a conceptual diagram illustrating a first embodiment of a mapping method of L1 control information, and FIG. 6B is a conceptual diagram illustrating a second embodiment of a mapping method of L1 control information.

Referring to FIGS. 6A and 6B, one slot may include 4 minislots and may be used for downlink transmission or uplink transmission. CBg #1 to #3 may belong to data channels and may be set within a scheduled bandwidth. In FIG. 6A, a CB for L1 control information may be mapped to all minislots belonging to one slot, and a CB for L1 control information may be mapped to an RS (eg, DM-RS) and an adjacent RE. can In FIG. 6B, CBs for L1 control information may be mapped to some minislots, and CBs for L1 control information may be mapped to RSs (eg, DM-RSs) and neighboring REs.

When a CB for L1 control information is mapped to an RE close to a DM-RS for a data channel, an error due to a channel interpolation operation after channel estimation can be reduced. In a communication system supporting MIMO that transmits two or more layers, the above-described RE mapping method of L1 control information may be applied. For example, L1 control information may be mapped to REs only in one layer. In this case, the base station may inform the terminal of the layer to which the L1 control information is mapped using downlink control information including resource allocation information of the data channel. Therefore, the terminal receiving the downlink control information can check the layer to which the L1 control information is mapped, and can perform a demapping operation or a mapping operation on the L1 control information in the checked layer. Alternatively, the base station may inform the terminal of port information about the layer to which the L1 control information is mapped using the downlink control information. The terminal can change the layer according to the instruction of the base station, and thus a spatial diversity gain can be obtained.

Alternatively, L1 control information may be mapped to all layers through which data channels are transmitted. In this case, since resources available for transmission of the data channel decrease, the coding rate of the data channel may increase. Therefore, the base station can determine the size of resources allocated for the data channel in order to maintain an appropriate coding rate.

A reception error of the L1 control information may be reduced by obtaining a frequency diversity gain. Accordingly, the L1 control resource may be transmitted through two or more frequency resources (eg, frequency band, subcarrier) within a bandwidth scheduled for the data channel.

■ Types of L1 control information (eg, DCI type or UCI RE by type) mapping Way

Each of the downlink control information types may have a different priority, and each of the uplink control information types may have a different priority. Accordingly, the location of the RE mapping may vary according to the priority of the downlink control information type or the uplink control information type.

If the size and location of resources occupied by L1 control information are the same within the resources scheduled for the data channel, the DCI type (or uplink control information type) with the highest priority may be mapped to the RE first, , After that, a downlink control information type (or uplink control information type) having a relatively low priority may be mapped to the RE. In this case, since a downlink control information type (or uplink control information type) having a high priority may be mapped to an RE relatively close to an RS (eg, DM-RS), a downlink control information type having a high priority A reception error of a link control information type (or an uplink control information type) can be reduced.

On the other hand, if L1 control information is allocated only to REs around the RS and there is no data to be transmitted, since no signal is transmitted through the remaining REs except for the REs to which the RS and L1 control information are allocated, the resource usage rate decreases. can do. In order to solve this problem, L1 control information having a relatively low priority, as in the following embodiments, may be mapped to other REs other than REs around the RS.

7A is a conceptual diagram illustrating a third embodiment of a method for mapping L1 control information, and FIG. 7B is a conceptual diagram illustrating a method for mapping L1 control information according to a fourth embodiment.

Referring to FIGS. 7A and 7B , one slot may include 4 minislots, and a data channel may not be transmitted within one slot. In FIG. 7A, a CB for L1 control information having a high priority may be mapped to all minislots belonging to one slot, and may be mapped to an RS (eg, DM-RS) and an adjacent RE. . On the other hand, CBs for L1 control information having a low priority may be mapped to all minislots belonging to one slot, and may be mapped to other REs other than REs around RS (eg, DM-RS). can

In FIG. 7B, CBs for L1 control information with high priority may be mapped to some minislots, and may be mapped to RSs (eg, DM-RSs) and neighboring REs. On the other hand, CBs for L1 control information having a low priority may be mapped to some minislots, and may be mapped to other REs other than REs around the RS (eg, DM-RS).

Although the above-described L1 control information mapping methods have been described based on one slot or one minislot, the L1 control information can be mapped to REs to fit a boundary between a plurality of slots or a plurality of minislots.

Meanwhile, when the terminal transmits aperiodic CSI to the base station, four types of uplink control information (eg, uplink control information type-1, uplink control information type-2, and uplink control information type- 3 and uplink control information type-4) may exist. Each of the four uplink control information types may have different priorities, and the RE mapping method of the uplink control information type may vary according to the priorities. The uplink control information type including at least one of RI and CRI may be mapped to REs around the DM-RS, and the uplink control information type including at least one of CQI and PMI is not an RE around the DM-RS. Can be mapped to other REs. That is, L1 control information (eg, DCI type or uplink control information type) having a low priority may be mapped to other REs other than REs around the DM-RS. Alternatively, when there is only one DCI type or uplink control information type, L1 control information (eg, DCI type or uplink control information type) is not only REs around the DM-RS but also REs around the DM-RS. It can also be mapped to other REs than .

■ CBg-based TB transfer method

8 is a conceptual diagram illustrating a first embodiment of a data channel.

Referring to FIG. 8 , a plurality of TBs may be configured within a system bandwidth, and each of the plurality of TBs may be configured within one slot. A TB can contain one or more CBgs, and one CBg can be mapped to one or more minislots. For example, TB #3 may contain 3 CBgs. If one slot includes 4 minislots, CBg #1 of TB #3 may be mapped to minislots #0-1, and CBg #2 of TB #3 may be mapped to minislots #1-2. CBg #3 of TB #3 may be mapped to minislot #3. When downlink transmission is performed, a TB may be transmitted through a downlink data channel, and a slot in which the TB is configured may be referred to as a "DL slot". When uplink transmission is performed, TB may be transmitted through an uplink data channel, and a slot in which the TB is configured may be referred to as a “UL slot”.

A base station may transmit TB to terminals (eg, a first terminal and a second terminal) using a downlink data channel. The downlink data channel established for the first terminal may be referred to as "downlink data channel #1", and the downlink data channel established for the second terminal may be referred to as "downlink data channel #2". A downlink data channel may belong to one slot regardless of a slot type (eg, DL slot, DL-centric slot, etc.), and one TB may be transmitted in one slot. Frequency hopping may be performed for each minislot according to the RRC setting or DCI of the base station.

When a resource to which TB #3 is mapped is configured as downlink data channel #1, downlink data channel #2 may be transmitted through one or more minislots belonging to TB #3. When the priority of the downlink data channel #2 is higher than that of the downlink data channel #1, the downlink data channel #1 may not be transmitted through some resources among resources to which TB #3 is mapped. In this case, the base station may transmit information indicating that the downlink data channel #1 is not transmitted through some of the resources configured for the downlink data channel #1 (ie, a preemption indicator) to the first terminal. That is, the preemption indicator may indicate that downlink data channel #2 is transmitted through some resources among resources configured for downlink data channel #1.

The preemption indicator may indicate the location of a physical resource on which the downlink data channel #1 is not transmitted (ie, the location of a physical resource on which the downlink data channel #2 is transmitted). For example, the preemption indicator may indicate time-frequency resource information of a specific slot, time-frequency resource information of one or more mini-slots within a specific slot, and the like. Here, time resource information of a slot (or minislot) may be a slot index (or minislot index), and frequency resource information of a slot or minislot may be a subcarrier index, a subband index, a PRB, and the like.

The first terminal may receive a preemption indicator from the base station, and based on the preemption indicator, it may be determined that the downlink data channel #2 is transmitted through some resources among resources configured for the downlink data channel #1. When downlink data channel #1 is received, UE 1 may generate a HARQ response for downlink data channel #1. The size of the HARQ response may vary according to rank. For example, when the rank is 1, 2, 3, or 4, the size of the HARQ response may be 1 bit. If the rank is 5, 6, 7 or 8, the size of the HARQ response may be 2 bits. The UE may generate one HARQ response bit per TB or CBg.

■ HARQ response transmission method 1 (hereinafter referred to as "Method 1")

The base station may inform the first terminal of the number of CBgs constituting the TB. For example, the base station may inform the first terminal of the number of CBgs constituting the TB using "higher layer signaling procedure" or "combination of higher layer signaling procedure and DCI transmission procedure". Here, DCI may include resource allocation information of downlink data channel #1. In Method 1, the preemption indicator may not be used. That is, the base station may not transmit a preemption indicator indicating transmission of downlink data channel #2 to the terminal. Alternatively, even when a preemption indicator indicating transmission of downlink data channel #2 is received from the base station, the first terminal may generate an HARQ response without considering the preemption indicator.

Terminal 1 may generate an HARQ response of downlink data channel #1 in units of CBg regardless of reception of the preemption indicator. The size of the HARQ response (eg, 1 bit or 2 bits) may vary depending on the rank. The first terminal may transmit a HARQ response to the base station using an uplink control channel. For example, when TB #1 of FIG. 8 includes L CBgs, TB #2 of FIG. 8 includes M CBgs, and TB #3 of FIG. 8 includes N CBgs, TB #1 Upon receiving -3, UE 1 may generate "L+M+N" HARQ responses.

In a communication system supporting MIMO, TDD, CA, or DC, a first terminal may transmit HARQ responses of a plurality of downlink data channels #1 through one uplink control channel. Here, the number of HARQ responses generated by the first terminal may correspond to the number of CBgs belonging to a plurality of downlink data channels #1.

■ Transmission Method 2 of HARQ Response (hereinafter referred to as "Method 2") : This method does not generate/transmit an HARQ response for a punctured CBg.

The base station may transmit a preemption indicator indicating transmission of downlink data channel #2 to the first terminal, and may transmit downlink data channel #1 to the first terminal. Upon receiving the downlink data channel #1, UE 1 may generate an HARQ response of the downlink data channel #1 in units of TB or CBg. In this case, the first terminal may generate an HARQ response in consideration of the preemption indicator received from the base station.

Specifically, UE 1 may generate an HARQ response of downlink data channel #1 in units of CBg in the resource (eg, slot, minislot) indicated by the preemption indicator, whereas In resources other than resources, an HARQ response of downlink data channel #1 may be generated in units of TB. The first terminal may transmit the generated HARQ response to the base station through an uplink control channel corresponding to downlink data channel #1.

For example, when TB #1 of FIG. 8 includes L CBgs, TB #2 of FIG. 8 includes M CBgs, and TB #3 of FIG. 8 includes N CBgs, TB #1 Upon receiving -3, UE 1 may generate a 1-bit HARQ response to TB #1, a 1-bit HARQ response to TB #2, and a 1-bit HARQ response to TB #3. The first terminal may transmit a “1+1+1” bit HARQ response to the base station through an uplink control channel. Here, since UE 1 does not know transmission-related information (eg, modulation order, coding rate, etc.) of downlink data channel #2, it can be regarded as having received only downlink data channel #1, and it can be regarded as having received only downlink data channel #1. CBg for #1 can be demodulated.

■ HARQ response transmission method 3 (hereinafter referred to as “method 3”) : This method considers the granularity of the HARQ response for the punctured CBg.

The base station may transmit a preemption indicator indicating transmission of downlink data channel #2 to the first terminal, and may transmit downlink data channel #1 to the first terminal. Upon receiving the downlink data channel #1, UE 1 may generate an HARQ response of the downlink data channel #1 in units of TB or CBg. In this case, the first terminal may generate an HARQ response in consideration of the preemption indicator received from the base station.

Specifically, UE 1 may divide the TB received in the slot indicated by the preemption indicator into a plurality of CBgs, and generate an HARQ response for each of the plurality of CBgs. For example, TB #1 in FIG. 8 includes L CBgs, TB #2 in FIG. 8 includes M CBgs, TB #3 in FIG. 8 includes N CBgs, and the preemption indicator is slot When #2 is indicated, UE 1 receiving TB #1-3 sends a 1-bit HARQ response to TB #1, an M-bit HARQ response to TB #2, and a 1-bit HARQ to TB #3 response can be generated. The first terminal may transmit a “1+M+1” bit HARQ response to the base station through an uplink control channel.

Meanwhile, the "method of transmitting the HARQ response" may vary according to the specificity of the information indicated by the preemption indicator.

■ HARQ response transmission method 4 (hereinafter referred to as "method 4") : HARQ response for CBg indicated by the preemption indicator is not generated/transmitted.

When the preemption indicator indicates slot #2 of FIG. 8, UE 1 may not generate HARQ responses to CBgs belonging to downlink data channel #1 received in slot #2 (ie, "Method 4 "). In the case of "Method 4", HARQ responses to CBgs received through slot #2 of FIG. 8 may not be transmitted.

In addition, in the case of “Method 4”, downlink data channel #1 received through slot #2 of FIG. 8 may include 3 CBgs, and the 3 CBgs initially transmitted may not be stored in the buffer, HARQ combining of the three retransmitted CBgs may not be performed. The above-described operation may be applied when the downlink data channel #1 is allocated by downlink control information or when the downlink data channel #1 is allocated by L1 activation. The first terminal may not interfere with other terminals by not transmitting part or all of the uplink control channel including only the HARQ response bits indicating the NACK. In addition, when the size of an HARQ response codebook (eg, HARQ ACK codebook) used in a communication system supporting TDD, CA, or DC is reduced, reception quality of an uplink control channel can be improved.

■ HARQ response transmission method 5 (hereinafter referred to as “method 5”) : A fixed HARQ response (eg, NACK or ACK) may be generated/transmitted as a HARQ response to CBg indicated by the preemption indicator. Alternatively, when the preemption indicator indicates slot #2 of FIG. 8, UE 1 receives a fixed HARQ response (eg, NACK or ACK) (i.e., “Method 5”). In the case of "Method 5", NACK may be transmitted as a HARQ response to CBgs received through slot #2 of FIG. 8.

Transmitting the NACK for the CBgs indicated by the preemption indicator may be overhead, but the base station receiving the NACK from the first terminal may determine that the preemption indicator was successfully received from the first terminal. The HARQ combining method in "Method 5" may be the same as the HARQ combining method in "Method 4".

When a first terminal performing communication using one carrier transmits 1-bit uplink control information through an uplink control channel (for example, considering PUCCH formats 1/1a/1b in an LTE communication system) case), the first terminal using "method 4" may not transmit the uplink control channel, and the first terminal using "method 5" may transmit NACK through the uplink control channel. In a communication system supporting TDD, CA, or DC, when UE 1 transmits uplink control information of 2 bits or more through an UL control channel, UE 1 using "Method 5" responds with HARQ indicating NACK. Bits can be encoded, and encoded HARQ response bits can be mapped to uplink control channels.

Meanwhile, the preemption indicator may be a bitmap indicating resources through which downlink data channel #2 is transmitted. The bitmap may indicate at least one of a time resource (eg, slot, minislot, symbol, etc.) and a frequency resource (eg, subband, subcarrier, etc.). For example, if the preemption indicator indicates slots #2 and 0,0,1,0 in FIG. 8, 0,0,1,0 may indicate minislots #0-3 belonging to slot #2, and , downlink data channel #2 can be transmitted in minislot #2 marked with "1".

Upon receiving the preemption indicator, UE 1 can determine that CBg (eg, CBg #2) received in minislot #2 of slot #2 is downlink data channel #2. When CBg #1 is received in minislot #0-1 of slot #2, UE 1 may generate a HARQ response to CBg #1. When CBg #3 is received in minislot #3 of slot #2, UE 1 may generate a HARQ response to CBg #3. Terminal 1 may not generate a HARQ response for CBg #2 received in minislot #2 of slot #2 (ie, “Method 4”). Alternatively, UE 1 may generate a fixed HARQ response (eg, NACK or ACK) as a HARQ response to CBg #2 received in minislot #2 of slot #2 (ie, "Method 5" ).

Terminal 1 may transmit HARQ responses to CBgs received through slot #2 to the base station through an uplink control channel. In the case of "Method 4", the first terminal may transmit "HARQ response for CBg #1 + HARQ response for CBg #3" to the base station. In the case of "Method 5", the first terminal may transmit "HARQ response for CBg #1 + fixed HARQ response for CBg #2 + HARQ response for CBg #3" to the base station.

If CBg #2 is data that is initially transmitted, the terminal may not store CBg #2 in the buffer. If CBg #2 is retransmitted data, the terminal may not perform HARQ combining of CBg #2 already stored in the buffer and retransmitted CBg #2. When the HARQ response for CBg #2 is generated in "Method 4", the transmission time of the HARQ response for CBg #2 may be different from the transmission time of HARQ responses for CBg #1 and #3. The transmission time of the HARQ response for CBg #2 may be set based on downlink control information indicating retransmission of CBg #2.

■ HARQ response transmission method 6 (hereinafter referred to as “method 6”) : Among CBgs belonging to a TB, HARQ responses to CBgs other than the CBgs indicated by the preemption indicator can be transmitted in a bundling manner. . When a fixed HARQ response for CBg #2 is generated in "Method 5", the fixed HARQ response may be transmitted at a predefined time point. In the case of "Method 6", the first terminal may generate one HARQ response by performing a logical AND operation on the HARQ response of CBg #1 and the HARQ response of CBg #3, and generate one HARQ A response (ie, a bundled HARQ response) may be transmitted to the base station through an uplink control channel.

According to "Method 6", even when the first terminal does not receive the preemption indicator, the size of the HARQ response codebook can be maintained. In addition, the first terminal reports decoding results for CBg #1 and #3 other than CBg #2 to the base station by transmitting 1-bit or 2-bit uplink control information through an uplink control channel allocated by the base station can do.

If the fixed HARQ response to CBg #2 is NACK and the base station receives an ACK from the first terminal, the base station may determine that both HARQ responses to CBg #1 and 3 are ACKs. On the other hand, when a NACK is received from the first terminal, the base station may not be able to distinguish a CBg whose HARQ response is a NACK. The base station may receive the HARQ response of CBg #2 at a transmission time point different from the transmission time point of the HARQ responses of CBg #1 and #3. The transmission time of the HARQ response for CBg #2 may be set based on downlink control information indicating retransmission of CBg #2.

Meanwhile, the preemption indicator may include slot # 2 of FIG. 8 and a bitmap indicating minislots belonging to slot # 2 (ie, 0, 0, 1, 0) and frequency resource information. In this case, UE 1 bases the downlink data channel #1 (eg, CBgs belonging to downlink data channel #1) and the downlink data channel #2 (eg, CBgs) based on the information included in the preemption indicator. It is possible to check whether there is a collision between CBgs belonging to downlink data channel #2).

If the collided CBg is data that is initially transmitted, UE 1 may not store the corresponding CBg in the buffer. Alternatively, when the collided CBg is retransmitted data, the first terminal may not perform HARQ combining on the corresponding CBg. In addition, UE 1 may not generate an HARQ response to the collided CBg. On the other hand, when the non-collision CBg is data that is initially transmitted, the first terminal may store the corresponding CBg in a buffer. Alternatively, when the non-collision CBg is retransmitted data, the first terminal may perform HARQ combining on the corresponding CBg. In addition, UE 1 may generate a HARQ response to a non-collision CBg.

If the specific CBg transmitted from the base station is not received by the first terminal through downlink data channel #2 and decoding of the specific CBg is not required, "Method 4", "Method 5" or "Method 6" may be used. . In "Method 4", when a specific CBg is initially transmitted data, the first UE may store the specific CBg in a buffer. On the other hand, when a specific CBg is retransmitted data in "Method 4", the first UE may not perform HARQ combining on the specific CBg. In addition, UE 1 may not generate an HARQ response for a specific CBg.

In "Method 5", UE 1 may generate a fixed HARQ response for a specific CBg. When a specific CBg is data that is initially transmitted, UE 1 may not store the specific CBg in a buffer. When a specific CBg is retransmitted data, UE 1 may not perform HARQ combining on the specific CBg.

In "Method 6", UE 1 may generate one HARQ response by performing a logical AND operation on HARQ responses of CBgs other than a specific CBg among all CBgs belonging to the TB. When a specific CBg is data that is initially transmitted, UE 1 may not store the specific CBg in a buffer. When a specific CBg is retransmitted data, UE 1 may not perform HARQ combining on the specific CBg. The base station may receive the HARQ response of CBg #2 at a transmission time point different from the transmission time point of the HARQ responses of CBg #1 and #3. The transmission time of the HARQ response for CBg #2 may be set based on downlink control information indicating retransmission of CBg #2.

Meanwhile, control information indicating a CBg index (hereinafter referred to as "collision CBg index") belonging to downlink data channel #1 colliding with downlink data channel #2 may be transmitted through a downlink control channel. Control information indicating a collision CBg index may be distinguished from downlink control information indicating retransmission of a preemption indicator and a specific CBg. When control information indicating a collision CBg index (ie, CBg #2) is received, the first terminal may generate HARQ responses by performing a decoding operation on CBg #1 and #3, and for CBg #2 A decoding operation may not be performed. In this case, "Method 4", "Method 5" or "Method 6" may be applied. If the CBg corresponding to the collision CBg index is initially transmitted data, UE 1 may not store the corresponding CBg in the buffer. Alternatively, when the CBg corresponding to the collision CBg index is retransmitted data, the first terminal may not perform HARQ combining on the corresponding CBg.

In "Method 4", UE 1 may not generate an HARQ response for a CBg corresponding to a collision CBg index. In "Method 5", UE 1 may generate a fixed HARQ response as an HARQ response to a CBg corresponding to a collision CBg index. In "Method 6", UE 1 may generate one HARQ response by performing a logical AND operation on HARQ responses of CBgs other than the CBg corresponding to the collision CBg index among all CBgs belonging to the TB. The base station may receive the HARQ response of CBg #2 at a transmission time point different from the transmission time point of the HARQ responses of CBg #1 and #3. The transmission time of the HARQ response for CBg #2 may be set based on downlink control information indicating retransmission of CBg #2.

Meanwhile, when the above-described embodiments are applied to a communication system supporting CA, a base station may configure one or more CBgs for each component carrier (CC), and one or more CBgs may be transmitted through a downlink data channel. The above-described embodiments may be applied to a communication system supporting TDD as well as a communication system supporting CA. In this case, the slot index may correspond to the CC index.

9 is a conceptual diagram illustrating a first embodiment of an HARQ response in a communication system supporting CC.

Referring to FIG. 9, 5 CCs (eg, CC #0 to #4) may be configured, 1 CBg may be configured in CC #0, and 2 CBgs may be configured in CC #1 3 CBgs can be set in CC #2, 1 CBg can be set in CC #3, and 4 CBgs can be set in CC #4. CC #0 to #4 may be set by "higher layer signaling procedure" or "combination of higher layer signaling procedure and downlink control information transmission procedure".

The base station can transmit 11 CBgs through the downlink data channel. Here, CBg indicated by A(ACK) may indicate a CBg successfully received by UE 1 among CBgs received through downlink data channel #1, and CBg indicated by N(NACK) is a downlink data channel Among the CBgs received through #1, a CBg that was not successfully received by the first terminal may be indicated. CBg indicated as M (missing) is a CBg that is not transmitted through downlink data channel #1 (eg, resource occupied by CBg transmitted through downlink data channel #2 and transmitted through downlink data channel #1). CBg) that could not be transmitted. When the preemption indicator indicating the CBg indicated by M is received from the base station, the first terminal can distinguish the CBg indicated by M. The reason UE 1 failed to decode the downlink control channel #1 to which the corresponding CBg is assigned is because the base station did not transmit the downlink control channel #1 and transmitted the downlink data channel #2. It can be interpreted that it is because some of the CBg belonged to were preoccupied.

10 is a conceptual diagram illustrating a first embodiment of a HARQ response codebook in a communication system supporting CC, and FIG. 11 is a conceptual diagram illustrating a second embodiment of an HARQ response codebook in a communication system supporting CC.

Referring to FIGS. 10 and 11 , a number displayed in CBg may indicate an encoding order of an HARQ response for the corresponding CBg. The base station may perform a decoding operation on the HARQ response based on the HARQ response codebook having the number of two cases depending on whether the terminal has received the preemption indicator. The base station may transmit a preemption indicator for each CC. Alternatively, the base station may transmit a preemption indicator through one CC. In this case, the base station may perform RRC configuration for performing cross carrier scheduling for the terminal. In this case, even when the CC on which the preemption indicator is received is different from the CC on which the downlink data channel is received, the HARQ response may be generated in consideration of the preemption indicator. That is, "Method 1", "Method 2", "Method 3", "Method 4", "Method 5" or "Method 6" may be applied.

When the terminal does not recognize CBg #1 of CC #2 and CBg #0 of CC #3 as M, the terminal performs a decoding operation on CBg #1 of CC #2 and CBg #0 of CC #3 to obtain an HARQ response can create The terminal may assign an order to CBg according to a predefined HARQ response codebook, and may encode the HARQ response of CBg according to the assigned order. If the UE does not recognize CBg #1 of CC #2 and CBg #0 of CC #3 as M, the coding sequence for the HARQ response of CBg may be assigned as shown in FIG. 10 . In this case, the unrecognized CBg may not be included in the encoding order.

The base station may transmit a downlink assignment index (DAI) to the terminal. Alternatively, the base station may inform the terminal of the size of the HARQ response codebook through a higher layer signaling procedure. Therefore, the terminal can check the size of the HARQ response codebook by DAI or higher layer signaling procedure.

On the other hand, if CBg #1 of CC #2 and CBg #0 of CC #3 are recognized as M, the terminal may not perform a decoding operation on CBg #1 of CC #2 and CBg #0 of CC #3. CBg #1 of CC #2 and CBg #0 of CC #3 may not generate HARQ responses. The terminal may assign an order to CBgs excluding CBg #1 of CC #2 and CBg #0 of CC #3 among all CBgs, and may encode the HARQ response of the CBg according to the assigned order. In this case, the coding order for the HARQ response of CBg may be assigned as shown in FIG. 11. Therefore, the HARQ responses of CBg #1 of CC #2 and CBg #0 of CC #3 may not be transmitted through the uplink control channel, and the UE encodes HARQ responses of the remaining CBgs based on a predefined HARQ response codebook can do.

The terminal can check the size of the HARQ response codebook by DAI or higher layer signaling procedure. However, since the decoding operation is not performed for a specific CBg (i.e., CBg #1 of CC #2 and CBg #0 of CC #3), the UE is able to perform a HARQ response codebook size greater than the size of the HARQ response codebook indicated by the DAI or higher layer signaling procedure. HARQ responses can be encoded by applying a small size.

■ How to transmit UCI

Next, a scenario in which a HARQ response or another downlink control channel is transmitted from a terminal to a serving base station through an uplink control channel will be described.

A case in which the uplink control channel includes 4 or more symbols is considered. For example, an uplink control channel may include 14 symbols corresponding to a maximum slot length. The unit of time in which the terminal performs frequency hopping may vary according to subslot (or minislot) configuration. Since the length of a slot is variable in a communication system supporting dynamic TDD, the serving base station may inform the terminal of the length of the uplink control channel in advance. The length of the uplink control channel may be indicated by downlink control information. For example, downlink control information used to schedule a downlink data channel may include length information of an uplink control channel.

In another embodiment, when the serving base station transmits common control information including a slot format indicator on a physical downlink control channel (eg, a group-common downlink control channel) , the UE may determine the length of the uplink control channel based on the slot format indicator. The slot format indicator may indicate configuration of a DL-UL symbol in a corresponding slot. The slot format indicator transmitted by the serving base station may indicate both the format of the current slot and the format of future slots. For example, the serving base station may transmit common control information including k slot format indicators (eg, SFI #1, SFI #2, ..., SFI #k) to the terminal for each slot. Within the common control information, k slot format indicators may be concatenated.

Upon receiving k slot format indicators, the terminal can determine that slot format indicator #1 indicates the format of the current slot #n, and slot format indicator #2 indicates the format of slot #(n+1). It can be determined that the slot format indicator #k indicates the format of the slot #(n+k). When the interval between the downlink data channel and the uplink control channel through which the HARQ response for the downlink data channel is transmitted is k, the terminal performs the uplink link based on the slot format indicator received through the downlink data channel set in slot #n. The format of slot #(n+k) in which the control channel is set can be checked. The slot format indicator may indicate not only a format of a slot in which an uplink control channel is configured, but also a format of a slot in which an uplink data channel is configured.

When the serving base station provides a communication service to terminals having different uplink control channel transmission times, a plurality of slot format indicators for the corresponding terminals may be transmitted through common control information. For example, when UE 1 receives a downlink data channel in slot #n and transmission timing of an HARQ response of UE 1 is slot #(n+3), UE 1 receives slot #(n+3). ), it is necessary to know the length of the uplink section. When UE 2 receives a downlink data channel in slot #n and the transmission timing of the HARQ response of UE 2 is slot #(n+4), UE 2 receives uplink data in slot #(n+4). You need to know the length of the interval.

The minimum time required for the UE to generate an HARQ response (eg, UCI, uplink control information) may be defined in the 3GPP TS. Alternatively, the serving base station may set a minimum time necessary for generating an HARQ response (eg, UCI, uplink control information) in the terminal by considering the capability of the terminal.

If the minimum time required for generating the HARQ response in the first terminal is the time corresponding to two slots, the terminal will at the latest in the format of slot #(n+3) in slot #n (e.g. slot #(n In +3), the length of the uplink section) must be known. In this case, the terminal may generate HARQ responses in slots #(n+1) and #(n+2), and may transmit the generated HARQ responses in slot #(n+3). If the minimum time required for generating the HARQ response in the second terminal is the time corresponding to one slot, the terminal may at the latest in the format of slot # (n + 4) in slot # (n + 2) (e.g., slot The length of the uplink section in #(n+4)) must be known. In this case, the terminal may generate an HARQ response in slot #(n+3) and transmit the generated HARQ response in slot #(n+4). The serving base station may transmit slot format indicators of different slots in a broadcast manner at different times to support uplink control information transmission operations of the first terminal and the second terminal. The above-described uplink control information transmission operation may be performed based on FIGS. 12A and 12B below.

12A is a timing diagram illustrating a method of transmitting uplink control information according to a first embodiment, and FIG. 12B is a timing diagram illustrating a method of transmitting uplink control information according to a second embodiment.

12a and 12b, the serving base station may transmit a downlink data channel and a preemption indicator to terminal #i (i=1,2) in slot #n. Terminal #i may receive a downlink data channel and a preemption indicator in slot #n, and may transmit an HARQ response to the downlink data channel in slot #(n+k _i ). The minimum time required for UE _#i to generate an HARQ response (eg, UCI, uplink control information) may be Δi. Here, the time unit of _Δi may be a slot, and _Δi may be 0 or more slots. In this case, UE #i uses the slot format indicator of slot # (n+k _i ) in slot # (n+k _i -Δ _i ) to transmit the HARQ response (eg, UCI, uplink control information). You should know. Therefore, the serving base station can transmit the slot format indicator for terminal #i through the common control channel.

In FIG. 12a, the serving base station can identify all terminals #i having the same “n+k _i -Δ _i ”, and assign all slot format indicators applied to slot #(n+k _i ) to slot #(n+k _i -Δ _i ) can be transmitted using a common control channel. Since the serving base station knows the number of terminals operating in the RRC_connected state, it can minimize the size of the common control channel (eg, common control information) by minimizing the number of slot format indicators. However, a reception error of the common control channel may occur, and in order to solve this problem, the serving base station may transmit the common control channel using a low coding rate. In addition, the serving base station may repeatedly transmit the slot format indicator twice or more. For example, in FIG. 12B, the serving base station may repeatedly transmit the slot format indicator three times. That is, slot format indicators for a plurality of specific slots may be transmitted through the downlink control channel, and the slot format indicator for one specific slot may be transmitted once in the downlink control channel. For example, a slot format indicator transmitted through a previous downlink control channel may be retransmitted through a current downlink control channel. In this case, the number of transmissions of the slot format indicator may be three times as shown in FIG. 12B.

Meanwhile, the RE mapping structure of the uplink control channel may be independent of the number of symbols occupied by the uplink control channel. The encoding operation in the time domain may be performed based on different encoding rates according to the number of symbols occupied by the uplink control channel. For example, a spreading code (eg, orthogonal cover code (OCC)) may be defined for each symbol in the time domain. Therefore, a method of performing an encoding operation in the frequency domain may be preferable to a method of performing an encoding operation in the time domain. However, when the UE knows the length of the uplink control channel, it can perform a coding operation in the time domain as well as a coding operation in the frequency domain. When information indicating that the frequency domain is dynamically changed is not received from the base station, the terminal can generate an uplink control channel by performing an encoding operation on the time-frequency domain set/instructed by the base station.

■ The terminal is coverage Transmission method of uplink channel when located at the boundary

The base station may inform the terminal (eg, terminal located at the coverage boundary of the base station) of the number of repeated transmissions of the uplink control channel (eg, PUCCH, UCI, HARQ response) through a higher layer signaling procedure, and accordingly The terminal may repeatedly transmit the uplink control channel. Repeated transmission of the uplink control channel may be configured for PUCCH formats 1/1a/1b used for transmission of HARQ responses in the primary cell of the UE. In addition, the base station transmits bundling (eg, different redundancy versions (RVs) through TTI bundling) of an uplink data channel (eg, physical uplink shared channel (PUSCH)) through a higher layer signaling procedure to the terminal. (eg, a terminal located at a coverage boundary of a base station), and accordingly, the terminal can perform bundling transmission for an uplink data channel.

When a terminal located at a coverage boundary of a base station requires transmission of downlink data more than transmission of uplink data, the base station may allocate more downlink data channels to the terminal than uplink data channels. In this case, since the base station cannot transmit downlink data only through downlink adaptation, it may additionally allocate frequency resources for downlink data transmission through frequency aggregation. In addition, the base station can more often allocate time resources for downlink data transmission. Therefore, as in the following embodiment, a HARQ response for other downlink data may occur before repeated transmission of the HARQ response for downlink data is completed.

13 is a timing diagram illustrating a first embodiment of HARQ response transmission in a communication system.

Referring to FIG. 13, a downlink data channel may be allocated through a dynamic or static scheduling procedure. A HARQ response to one downlink data channel can be transmitted through four uplink control channels. That is, the HARQ response may be repeatedly transmitted 4 times.

For example, the terminal may receive downlink data channel #1 in slot #n, and transmit HARQ response #1 (eg, uplink control channel #1) to the downlink data channel #1 in consecutive slots. It can be repeatedly transmitted from #(n+4) to #(n+7). In addition, the UE may receive downlink data channel #2 in slot #(n+2), and continuously transmit HARQ response #2 (eg, uplink control channel #2) to the downlink data channel #2. It can be repeatedly transmitted in slots # (n + 5) to # (n + 8). In this case, HARQ responses for different HARQ processes may be transmitted in slots #(n+5) to #(n+7). Therefore, the number of HARQ responses transmitted through slots #(n+4) or #(n+8) may be different from the number of HARQ responses transmitted through slots #(n+5) to #(n+7), respectively. there is. When the uplink control channel is repeatedly transmitted, the HARQ response may be encoded based on various schemes in order to appropriately maintain the number of HARQ responses. For example, the HARQ response may be generated in units of TB (or units of a small number of CBg).

Meanwhile, a location of a frequency resource in which an uplink control channel (eg, HARQ response) is repeatedly transmitted may be maintained the same. Alternatively, the uplink control channel may be repeatedly transmitted through different frequency resources. For example, the base station receives a corresponding signal (eg, reference signal) or information (eg, downlink path loss information, power headroom information, etc.) received from the terminal. A UE capable of estimating the location of a UE and providing information on frequency resources (eg, subcarrier index, PRB index) allocated for an uplink control channel through an uplink signaling procedure to a UE estimated to be located at the coverage boundary of the base station can inform

In an embodiment in which an uplink control channel is transmitted through the same frequency resource, a base station may require relatively many reference signals to estimate an uplink control channel of a terminal located at a coverage boundary of the base station. Therefore, the UE can transmit the DM-RS using the same frequency resource within the coherence time, and the base station can accurately estimate the uplink control channel using the DM-RS received from the UE. In this case, demodulation/decoding errors of the uplink control channel can be reduced.

When uplink control channels are transmitted through different frequency resources, a gain due to frequency multiplexing can be obtained. In this case, the base station can relatively accurately obtain an uplink control channel from a terminal located at a coverage boundary of the base station. However, since the amount of uplink control information transmitted through the uplink control channel is large, errors may occur. To solve this problem, the base station may perform a soft combining operation on uplink control information repeatedly received through an uplink control channel. The type and size of the uplink control information included in the uplink control channel may always be the same or different each time, but since the base station knows the RE mapping information of the uplink control information in advance, soft combining of the received uplink control information By performing the operation, demodulation/decoding errors can be reduced. For example, when the uplink control information includes a HARQ response, the UE can map the uplink control information to the RE using the HARQ response codebook defined in the 3GPP TS, and accordingly, the base station can perform uplink A HARQ response may be confirmed by performing a soft combining operation on control information.

The terminal may perform an encoding operation according to the size of uplink control information (eg, HARQ response) transmitted through the uplink control channel. For example, when the size of uplink control information (eg, HARQ response) is 1 bit or 2 bits, the terminal may perform an encoding operation using a spreading code. When the size of uplink control information (eg, HARQ response) is 3 bits or more, the terminal may perform an encoding operation using linear block codes (eg, Reed Muller code, Polar code).

When the uplink control channel is configured to be repeatedly transmitted through a higher-layer signaling procedure, the UE transmits an uplink control channel having a different RV (e.g., an uplink control channel having a different RV) for each transmission instance of the uplink control channel. link control information). Different types of uplink control information may have different RVs. In addition, different coding rates may be applied to each type of uplink control information having a different RV, and may be mapped to an RE of an uplink control channel. The base station can improve reception quality by performing a soft combining operation on uplink control information having different RVs. The method described above can be applied to a scenario in which the coding rate of an uplink control channel is maintained the same. For example, since the length of an uplink interval occupied by an uplink control channel is the same in a frequency division duplex (FDD) or TDD-based communication system, the terminal can maintain the same coding rate by using the same time-frequency resource. there is.

On the other hand, since the length of the uplink interval is variable in the dynamic TDD-based communication system, the length of the uplink control channel transmitted by the terminal may not be constant. In this case, the serving base station may inform the terminal of the length of the uplink interval. For example, the base station transmits resource allocation information (eg, uplink resource allocation information of an uplink control channel through which an HARQ response for a corresponding downlink data channel is transmitted) through a downlink control channel through which resource allocation information of a downlink data channel is transmitted. The length of the control channel, the position of the start symbol of the uplink control channel (eg, start symbol index), etc.) may be transmitted. When the terminal repeatedly transmits the uplink control channel n times in n slots, resource allocation information of the uplink control channel may be different for each slot. In this case, the base station may transmit resource allocation information of n uplink control channels through the downlink control channel. Here, n may be an integer greater than or equal to 1.

On the other hand, symbols that can be used as uplink control channels for each UL slot due to the existence of another terminal's uplink control channel (eg, narrow-range uplink control channel, short PUCCH), existence of SRS (sounding reference signal), etc. The number of may be variable. Since all symbols belonging to a UL slot cannot be used for an uplink control channel of one UE, the base station can inform the UE of resource allocation information of the uplink control channel through a signaling procedure even in a TDD or FDD-based communication system.

For example, the serving base station includes information (eg, the number of symbols used by the uplink control channel, the number of symbols used by the uplink control channel, the information of the symbol (eg, symbol per UL slot) used by the uplink control channel end symbol index, etc.) may be informed to the terminal. Information on symbols used by the uplink control channel is transmitted through a downlink control channel (eg, a downlink control channel through which resource allocation information of a downlink data channel corresponding to the uplink control channel is transmitted) or higher layer signaling. can be transmitted

In this case, the terminal can check information on symbols used by the uplink control channel. When the terminal can know the start symbol index of the uplink control channel, the time resource of the uplink control channel can be specified. A start symbol index of an uplink control channel may correspond to a slot format. The serving base station sets the start symbol index (eg, slot format) of the uplink control channel to the downlink control channel (eg, downlink control channel through which resource allocation information of the downlink data channel corresponding to the uplink control channel is transmitted). channel) or higher layer signaling. Alternatively, the serving base station may transmit the start symbol index (eg, slot format) of the uplink control channel in a broadcast manner through a separate downlink control channel. According to the method described above, the terminal can check the start symbol index of the uplink control channel and the number of symbols used by the uplink control channel in each of the UL slots.

However, the uplink control channel may not always be transmitted in consecutive UL slots. For example, in a TDD-based communication system, an uplink control channel may not be continuously transmitted through DL slots. Alternatively, when the number of symbols included in the UL slot is small, the uplink control channel may not be transmitted through the corresponding UL slot. That is, even when the maximum bandwidth (eg, the maximum number of PRBs) set by the serving base station is used for transmission of the uplink control channel, the maximum code rate (eg, the maximum code rate allowed in the 3GPP TS) is exceeded. When a high coding rate is required, an uplink control channel may not be transmitted through a corresponding UL slot.

Meanwhile, the serving base station transmits a slot format indicator indicating an unknown resource (eg, an unknown symbol or a slot including an unknown symbol) using a downlink control channel in a broadcast manner. can The UE may receive downlink data through an undetermined resource and may transmit a HARQ response (eg, uplink control information) to the downlink data. In addition, the terminal may transmit uplink data scheduled by a downlink control channel through an undetermined resource. Other terminals other than these terminals may not transmit/receive signals when undetermined resources and resources for transmission and reception partially overlap (for example, undetermined symbols occur in one or more symbols constituting resources set by higher layer signaling in the base station). there is. For example, undetermined resources may be used for transmission and reception of downlink and uplink data. Alternatively, undetermined resources may be used for various purposes.

If a resource (hereinafter referred to as "UL allocation resource") to which an uplink channel (eg, uplink data channel, uplink control channel) is to be transmitted does not overlap with an undetermined resource, the UE transmits the corresponding UL allocation resource An uplink channel may be transmitted. When a UL-allocated resource partially overlaps an undetermined resource, the UE may regard the overlapping resource as a UL-allocated resource and transmit an uplink channel through the considered UL-allocated resource. Alternatively, an uplink channel may not be transmitted due to an undetermined resource. In this case, an uplink channel that has not been transmitted due to an undetermined resource may not be counted as the number of repeated transmissions of the uplink channel. Alternatively, an uplink channel not transmitted due to an undetermined resource may be counted as the number of repeated transmissions of the uplink channel.

14A is a timing diagram illustrating a first embodiment of a method of transmitting an uplink channel in a communication system, and FIG. 14B is a timing diagram illustrating a second embodiment of a method of transmitting an uplink channel in a communication system.

Referring to FIGS. 14A and 14B, slot #(n+2) may be a slot including an undecided symbol, and an uplink channel (eg, uplink data channel, uplink) may be provided through slot #(n+2). link control channel) may not be transmitted. For example, when an undecided symbol and an uplink channel overlap, the uplink channel may not be transmitted through slot #(n+2). The uplink channel may be repeatedly transmitted 4 times in the time domain and may be transmitted in a frequency hopping scheme. In FIG. 14A, an uplink channel not transmitted by a slot including an undecided symbol may be counted as the number of repeated transmissions of the uplink channel. In this case, the actual number of repeated transmissions of the uplink channel (ie, 3 times) may be smaller than the predefined number of repeated transmissions (ie, 4 times). In FIG. 14B, an uplink channel not transmitted by a slot including an undecided symbol may not be counted as the number of repeated transmissions of the uplink channel. In this case, the actual number of repeated transmissions of the uplink channel (ie, 4 times) may be the same as the predefined number of repeated transmissions (ie, 4 times). In the embodiment shown in FIG. 14A, the reception error rate of the uplink channel may be greater than the reception error rate of the uplink channel in the embodiment shown in FIG. 14B.

Meanwhile, at least one of a time resource, a frequency resource, and a sequence resource used by an uplink control channel may be different for each slot. In this case, resource information of an uplink control channel of each slot may be transmitted through a downlink control channel used for transmission of resource allocation information of a downlink data channel. Accordingly, a time-frequency resource for an uplink control channel may be configured differently for each slot, and uplink control channels of a plurality of terminals may be transmitted in one slot in a time division multiplexing (TDM) scheme. When the length of a UL slot is variable in a TDD- or FDD-based communication system, the UE uses different time-frequency resources in a plurality of UL slots to maintain the same code rate of uplink control information in a plurality of UL slots. Uplink control information may be transmitted using For example, when the uplink control information is repeatedly transmitted twice, the UE can transmit the uplink control information through a resource consisting of 2 symbols and 12 subcarriers in the first UL slot, and the second Uplink control information can be transmitted through a resource consisting of 1 symbol and 24 subcarriers in a UL slot. Therefore, the coding rate of uplink control information in the first UL slot may be the same as the coding rate of uplink control information in the second UL slot.

In this case, the resource information (eg, resource index) of the uplink control channel signaled from the serving base station to the terminal is a time resource occupied by the uplink control channel in each of the UL slots (eg, the uplink control channel The number of symbols used for ) and frequency resources (eg, the number of PRBs used for an uplink control channel) may be indicated. In this case, the base station transmits a slot type using a downlink control channel used for transmission of resource allocation information of a downlink data channel or a separate downlink control channel to transmit an uplink control channel within a UL slot. The first symbol used may be informed to the terminal.

According to the methods described above, time resources for the uplink control channel may be allocated differently in each of the slots, and the terminal may repeatedly transmit the uplink control channel in consecutive slots based on the resource allocation information. . In this case, delay time due to repeated transmission of the uplink control channel can be reduced. As another method for indicating the length of the uplink control channel, the base station uses a separate downlink control channel instead of the downlink control channel used for transmission of resource allocation information of the downlink data channel. may be transmitted in a broadcast manner.

In this case, the UE can check the length of the uplink control channel in a UL slot (eg, a UL-centric slot). In addition, the terminal may check the last symbol index of the uplink control channel through a separate signaling procedure, and derive the number of symbols used for the uplink control channel based on the last symbol index of the uplink control channel. . However, if the uplink control channel is repeatedly transmitted and the length of the uplink control channel is different in each of the slots in which the uplink control channel is repeatedly transmitted, the uplink control channel (e.g., uplink control channel) in each corresponding slot information) may vary. In this case, the base station may not perform a soft combining operation on the uplink control channel (eg, uplink control information).

The terminal may perform an encoding operation for uplink control information based on the minimum coding rate set by the higher layer signaling procedure of the serving base station or the minimum coding rate defined in the 3GPP TS. The ratio of the number of modulated symbols (n) to the maximum number of bits (k) of uplink control information transmitted through the uplink control channel may indicate a coding rate. The terminal may generate modulation symbols by performing a modulation operation on the coded bits, and may map the modulation symbols to m REs constituting the uplink control channel. An effective coding rate of uplink control information may be a function of k, n, and m, and a coding rate maintained constant for a soft combining operation in a decoding procedure may be a function of k and n. For example, for soft combining of polar codes, k and n may be set to a fixed ratio. Here, each of k, n and m may be an integer of 1 or greater.

The size (m) of the uplink control channel may be calculated to obtain the coding rates (k, n). Since the uplink control channel in a dynamic TDD-based communication system occupies time resources of 4 symbols or more, the serving base station uses a higher layer signaling procedure to obtain a desired coding rate (k, n, m). Frequency resource information of the control channel (ie, bandwidth occupied by the uplink control channel) may be informed to the terminal.

That is, the serving base station may allocate the minimum resource of the uplink control channel to the terminal. When the terminal repeatedly transmits the uplink control channel k times or more, resource sizes (m) used for repeated transmission of the uplink control channel may be different. Here, k may be an integer greater than or equal to 2, and may be “n ≤ m”. The UE may repeatedly map modulation symbols to REs in order to maintain the coding rates (k, n). For example, the UE transmits n modulation symbols (eg, modulation symbols #1, 2, 3, ..., n to m REs (eg, RE #1, 2, 3, ..., m) ), and “m-n” modulation symbols to the remaining “m-n” REs (eg, RE #(n+1), (n+2), (n+3), …, m) (eg, modulation symbols #1, 2, 3, ..., m-n) may be repeatedly mapped. In addition, when uplink control information having different RVs is repeatedly transmitted, the terminal converts modulation symbols of uplink control information having different RVs based on the above-described method to maintain the coding rate (k, n). It can be repeatedly mapped to different numbers of REs.

Meanwhile, a location of a frequency resource used for transmission of an uplink control channel may be determined based on the following embodiments.

15A is a timing diagram illustrating a third embodiment of a method of transmitting an uplink channel in a communication system.

Referring to FIG. 15A, when a terminal repeatedly transmits an uplink control channel k or more times, the number of frequency bands used for transmission of the uplink control channel may be two or more. Here, k may be an integer greater than or equal to 2. The uplink control channel may be transmitted in the same UL slot in a frequency hopping scheme, and the same frequency hopping pattern may be used in UL slots in which the uplink control channel is repeatedly transmitted. In a dynamic or static TDD-based communication system, an uplink control channel may be transmitted using some symbols in a slot.

15B is a timing diagram illustrating a fourth embodiment of a method of transmitting an uplink channel in a communication system.

Referring to FIG. 15B, the terminal may repeatedly transmit the uplink control channel two or more times. The uplink control channel may be transmitted in a frequency hopping scheme in units of UL slots. In this case, the base station may configure the terminal through a higher layer signaling procedure not to perform frequency hopping for the uplink control channel within the same UL slot. A frequency multiplexing gain can be obtained by transmitting the uplink control channel through two frequency bands. In a dynamic or static TDD-based communication system, an uplink control channel may be transmitted using some symbols within a slot.

15C is a timing diagram illustrating a fifth embodiment of a method of transmitting an uplink channel in a communication system.

Referring to FIG. 15C, a terminal may repeatedly transmit an uplink control channel two or more times, and the uplink control channel may be transmitted through three or more frequency bands. That is, the base station may set the terminal to transmit the uplink control channel using three or more frequency bands through a higher layer signaling procedure. The uplink control channel may be transmitted in a frequency hopping scheme within the same UL slot, and the frequency hopping pattern of the uplink control channel may be different in each of the UL slots. The uplink control channel may be transmitted through two frequency bands in each of the UL slots, and the center frequencies applied in hopping of the uplink control channel in neighboring UL slots may be different from each other.

The base station may inform the terminal of the frequency hopping pattern of each UL slot through a higher layer signaling procedure. For example, the frequency hopping pattern may be indicated by a function of a UL slot index through which an uplink control channel is transmitted. To maximize the frequency multiplexing gain, the uplink control channel can be transmitted over the center band as well as the edge band in the frequency domain.

As a first embodiment of a method for informing a terminal of three frequency bands in which an uplink control channel is transmitted, the base station performs the number of repeated transmissions (k) of the uplink control channel and the frequency hopping of the uplink control channel through a higher-layer signaling procedure. The bandwidth (ΔF) and the location (f ₁ , f ₂ , ..., f _k ) of the center frequency of the uplink control channel in UL slots may be notified to the UE. When an uplink bandwidth preset by the base station is used as the frequency hopping bandwidth (ΔF) of the uplink control channel, the base station uses a higher layer signaling procedure to determine the center frequency positions (f ₁ , f ₂ , ..., f _k ) may not be notified to the terminal. The UE may transmit an uplink control channel using frequency resources "f _k -ΔF/2" and "f _k +ΔF/2" in the kth UL slot. Alternatively, the UE can identify the location of the frequency band in which the uplink control channel is transmitted based on the center frequency location (f ₁ , f ₂ , ..., f _k ) of the uplink control channel in UL slots and the UL slot index. .

As a second embodiment of a method for informing a terminal of three frequency bands in which an uplink control channel is transmitted, the base station uses a higher layer signaling procedure to determine the location of resources used for transmission of the uplink control channel in each of the UL slots ( For example, the location of a frequency resource) may be informed to the terminal. The terminal may calculate the location of a frequency resource actually used for transmission of an uplink control channel based on information obtained through a higher layer signaling procedure. For example, the base station may inform the terminal of frequency resources used for transmission of the uplink control channel through "a combination of a higher layer signaling procedure and a downlink control information transmission procedure". In this case, the terminal may calculate the location of a frequency resource used for transmission of the uplink control channel using a value set by a higher layer signaling procedure and a value indicated by the downlink control information. When the value set by the higher layer signaling procedure is different for each UL slot and the value indicated by the downlink control information is the same in the UL slots, the UE can calculate the locations of different frequency resources in the UL slots.

When the uplink control channel is transmitted through three or more frequency bands, the base station can receive the uplink control channel not only in the edge band of the frequency domain but also in the middle band. In this case, the uplink control channel of the first terminal may coexist with the uplink data channel of the second terminal. When scheduling UEs, the base station may adjust the frequency hopping boundary of the uplink control/data channel and the location of the DM-RS to be advantageous for coexistence. Terminals can multiplex DM-RSs of uplink channels using the CDMA scheme, and base stations can differentiate DM-RSs of terminals based on the CDMA scheme. Here, the DM-RS may be generated based on the same sequence (eg, Zadoff-Chu sequence, CAZAC (Constant Amplitude Zero AutoCorrelation) sequence).

■ How to simultaneously support PUSCH bundling transmission and repeated PUCCH transmission

In order to improve the transmission range of the uplink data channel, the serving base station may inform the terminal of the number of repeated transmissions of the uplink data channel through an uplink signaling procedure. In addition, in order to improve the transmission range of the uplink control channel, the serving base station may inform the terminal of the number of repeated transmissions of the uplink control channel through an uplink signaling procedure.

When uplink data is generated, the terminal may make a scheduling request for transmission of uplink data to the serving base station, and in response to the scheduling request from the serving base station, downlink control information including resource allocation information of an uplink data channel (eg, a downlink control channel) may be received. In addition, when downlink data is generated, the serving base station may transmit downlink control information (eg, downlink control channel) including resource allocation information of a downlink data channel to the terminal, indicated by the resource allocation information. Downlink data may be transmitted to the terminal through a downlink data channel. The UE may receive downlink data and generate an HARQ response to the downlink data.

In this case, if the UL slot in which the HARQ response for the downlink data is to be transmitted is the same as the UL slot in which the uplink data is to be transmitted, the UE transmits the HARQ response and the uplink data to the serving base station using the uplink data channel in the slot. can transmit Here, the UE may map the HARQ response to an area of an uplink data channel. Also, when the uplink control channel and the uplink data channel are repeatedly transmitted, UL slots through which the uplink control channel is transmitted may overlap UL slots through which the uplink data channel is transmitted.

16A is a timing diagram illustrating a first embodiment of a transmission scheme of an uplink control/data channel in a communication system, and FIG. 16B is a timing diagram illustrating a second embodiment of a transmission scheme of an uplink control/data channel in a communication system. 16C is a timing diagram illustrating a third embodiment of a transmission method of an uplink control/data channel in a communication system, and FIG. 16D is a timing diagram showing a fourth embodiment of a transmission method of an uplink control/data channel in a communication system. It is a timing diagram showing an example.

Referring to FIGS. 16A to 16D, the serving base station may first allocate an uplink data channel and then allocate an uplink control channel. The uplink data channel may be repeatedly transmitted four times, and the uplink control channel (eg, uplink control information) may be repeatedly transmitted four times. In this case, one or more slots among slots through which an uplink data channel is transmitted may overlap slots through which an uplink control channel is transmitted. Each of the uplink data channel and the uplink control channel may be transmitted based on a frequency hopping scheme.

In FIG. 16A, the terminal may transmit an uplink data channel through slot #0-1 (eg, a UL slot or a UL-centric slot), and an uplink data channel and an uplink control channel through slot #2- 3 (eg, UL slot or UL-centric slot), and the uplink control channel can be transmitted through slots # 4-5 (eg, UL slot or UL-centric slot) . That is, the uplink data channel and the uplink control channel can be simultaneously transmitted in slots #2-3.

In FIG. 16B, the terminal may transmit an uplink data channel through slot #0-1 (eg, a UL slot or a UL-centric slot), and uplink data including uplink data and uplink control information The channel may be transmitted through slots #2-3 (eg, UL slots or UL-centric slots), and the uplink control channel may be transmitted through slots # 4-5 (eg, UL slots or UL-centric slots). ) can be transmitted. That is, in slots #2-3, the uplink data channel and the uplink control channel may not be simultaneously transmitted, and the uplink data channel including uplink data and uplink control information may be transmitted.

In FIG. 16C, the terminal may transmit the uplink data channel through slot #0-1 (eg, UL slot or UL-centric slot), and slot #2 is a slot including an undetermined symbol. No signal may be transmitted through #2. For example, when a resource used for transmission of an uplink data channel or uplink control information overlaps an undetermined symbol, no signal may be transmitted through slot #2. An uplink channel not transmitted by a slot including an undecided symbol may not be counted as the number of repeated transmissions of the uplink channel. The terminal may transmit an uplink data channel including uplink data and uplink control information through slot # 3-4 (eg, UL slot or UL-centric slot), and transmit the uplink control channel through slot # It can be transmitted through 5-6 (eg, UL slot or UL-centric slot). That is, in slots #3-4, the uplink data channel and the uplink control channel may not be simultaneously transmitted, and the uplink data channel including uplink data and uplink control information may be transmitted.

In FIG. 16D, the terminal may transmit an uplink data channel through slot #0-1 (eg, a UL slot or a UL-centric slot), and slot #2 is a slot including an undetermined symbol. No signal may be transmitted through #2. For example, when a resource used for transmission of an uplink data channel or uplink control information overlaps an undetermined symbol, no signal may be transmitted through slot #2. An uplink channel not transmitted by a slot including an undecided symbol may be counted as the number of repeated transmissions of the uplink channel. The terminal may transmit an uplink data channel including uplink data and uplink control information through slot #3 (eg, a UL slot or a UL-centric slot). In this case, the uplink data channel can be transmitted in the first slot (ie, slot #3) in which it is determined that transmission of the uplink data channel is possible after the slot including the undecided symbol. In addition, the terminal may transmit the uplink control channel through slot #4-5 (eg, UL slot or UL-centric slot). That is, in slot #3, the uplink data channel and the uplink control channel may not be simultaneously transmitted, and the uplink data channel including uplink data and uplink control information may be transmitted.

In the embodiments of FIGS. 16A to 16D, when the serving base station calculates the number of PRBs for an uplink data channel, uplink data is punctured by uplink control information bits or rate matching (rate matching) for uplink data matching) may not be expected to be performed. Therefore, it may be desirable for the serving base station to allocate a slot for the uplink control channel to the terminal after repeated transmission of the uplink data channel is completed. Alternatively, the aforementioned problems can be solved by adjusting the size of uplink control information transmitted together with uplink data through an uplink data channel.

Unlike the embodiments shown in FIGS. 16A to 16D, in the embodiments shown in FIGS. 17A to 17D below, the serving base station may first allocate an uplink control channel and then allocate an uplink data channel. can

17A is a timing diagram illustrating a fifth embodiment of a transmission scheme of an uplink control/data channel in a communication system, and FIG. 17B is a timing diagram illustrating a sixth embodiment of a transmission scheme of an uplink control/data channel in a communication system. 17c is a timing diagram illustrating a seventh embodiment of a transmission method of an uplink control/data channel in a communication system, and FIG. 17d is an eighth embodiment of a transmission method of an uplink control/data channel in a communication system. It is a timing diagram showing an example.

17A to 17D, an uplink control channel (eg, uplink control information) may be repeatedly transmitted four times, and an uplink data channel may be repeatedly transmitted four times. In this case, one or more slots among slots through which an uplink control channel is transmitted may overlap slots through which an uplink data channel is transmitted. Each of the uplink control channel and the uplink data channel may be transmitted based on a frequency hopping scheme.

In FIG. 17A, the terminal may transmit an uplink control channel through slot #0-1 (eg, a UL slot or a UL-centric slot), and an uplink control channel and an uplink data channel through slot #2- 3 (eg, UL slot or UL-centric slot), and the uplink data channel can be transmitted through slots # 4-5 (eg, UL slot or UL-centric slot) . That is, the uplink control channel and the uplink data channel can be simultaneously transmitted in slots #2-3.

In FIG. 17B, the terminal may transmit an uplink control channel through slot #0-1 (eg, a UL slot or a UL-centric slot), and uplink data including uplink data and uplink control information The channel can be transmitted through slots #2-3 (eg, UL slots or UL-centric slots), and the uplink data channel can be transmitted through slots # 4-5 (eg, UL slots or UL-centric slots). ) can be transmitted. That is, in slots #2-3, the uplink control channel and the uplink data channel may not be simultaneously transmitted, and the uplink data channel including uplink data and uplink control information may be transmitted.

In FIG. 17C, the terminal may transmit the uplink control channel through slot #0-1 (eg, UL slot or UL-centric slot), and slot #2 is a slot including an undetermined symbol. No signal may be transmitted through #2. For example, when a resource used for transmission of an uplink data channel or uplink control information overlaps an undetermined symbol, no signal may be transmitted through slot #2. An uplink channel not transmitted by a slot including an undecided symbol may not be counted as the number of repeated transmissions of the uplink channel. The terminal may transmit an uplink data channel including uplink data and uplink control information through slot # 3-4 (eg, UL slot or UL-centric slot), and transmit the uplink data channel through slot # It can be transmitted through 5-6 (eg, UL slot or UL-centric slot). That is, in slots #3-4, the uplink control channel and the uplink data channel may not be simultaneously transmitted, and the uplink data channel including uplink data and uplink control information may be transmitted.

In FIG. 17D, the terminal may transmit the uplink control channel through slot #0-1 (eg, UL slot or UL-centric slot), and slot #2 is a slot including an undetermined symbol. No signal may be transmitted through #2. For example, when a resource used for transmission of an uplink data channel or uplink control information overlaps an undetermined symbol, no signal may be transmitted through slot #2. An uplink channel not transmitted by a slot including an undecided symbol may be counted as the number of repeated transmissions of the uplink channel. The terminal may transmit an uplink data channel including uplink data and uplink control information through slot #3 (eg, a UL slot or a UL-centric slot). In this case, the uplink data channel can be transmitted in the first slot (ie, slot #3) in which it is determined that transmission of the uplink data channel is possible after the slot including the undecided symbol. In addition, the terminal may transmit the uplink data channel through slot #4-5 (eg, UL slot or UL-centric slot). That is, in slot #3, the uplink control channel and the uplink data channel may not be simultaneously transmitted, and the uplink data channel including uplink data and uplink control information may be transmitted.

In the embodiments of FIGS. 17A to 17D, the serving base station calculates the number of PRBs for an uplink data channel, uplink data is punctured by uplink control information bits, or rate matching for uplink data is performed. can be expected In this case, the serving base station may transmit resource allocation information of an uplink data channel considering puncturing or rate matching of uplink data to the terminal. Therefore, the base station can minimize the effect of the uplink control information bit when decoding the uplink data channel.

On the other hand, when the uplink control information includes the HARQ response and CSI (eg, periodic CSI, semi-persistent CSI), the serving base station selects the uplink data channel in consideration of the uplink control information. resources can be allocated for When the uplink control information includes the HARQ response and the aperiodic CSI, since the serving base station can request the terminal to transmit the aperiodic CSI through the downlink control channel, the serving base station considers the corresponding uplink control information. Thus, resources for the uplink data channel can be allocated. When the uplink control information includes a HARQ response of 3 bits or more and the corresponding uplink control information is transmitted through the uplink data channel together with the uplink data, the UE may perform rate matching on the uplink data channel. . When the uplink control information includes a 1-bit or 2-bit HARQ response and the corresponding uplink control information is transmitted along with uplink data through an uplink data channel, the UE performs puncturing on the uplink data channel can do. In addition, when uplink control information is transmitted through an uplink data channel, the terminal may compress HARQ response bits included in the uplink control information.

For example, when a plurality of downlink data channels are received, the UE obtains a 1-bit or 2-bit HARQ response (eg, by performing a logical AND operation on HARQ responses to the plurality of downlink data channels received). For example, a 1-bit or 2-bit HARQ response for each space) can be generated. In this case, in order to transmit a 1-bit or 2-bit HARQ response through the uplink data channel, puncturing may be performed on the uplink data channel.

Alternatively, when a downlink data channel consisting of a plurality of CBgs is received, the terminal performs a logical AND operation on HARQ responses to the received plurality of CBgs (eg, a plurality of CBgs belonging to the same TB) It is possible to generate a 1-bit or 2-bit HARQ response by performing. When a 2-bit HARQ response is generated, the terminal may generate a 1-bit HARQ response by performing a logical AND operation on the 2-bit HARQ response. In this case, in order to transmit a 1-bit or 2-bit HARQ response through the uplink data channel, puncturing may be performed on the uplink data channel.

Therefore, when puncturing is performed on the uplink data channel to transmit the HARQ response through the uplink data channel, the amount of the HARQ response is limited to 1 bit or 2 bits, thereby minimizing reception errors in the decoding process of uplink data. It can be.

The embodiment described above may be the same as the embodiment shown in FIG. 18 .

18 is a timing diagram illustrating a ninth embodiment of a method for transmitting an uplink control/data channel in a communication system.

Referring to FIG. 18, the serving base station may transmit a downlink control channel set #1 composed of a plurality of downlink control channels including resource allocation information of a downlink data channel, and an uplink data channel 1810 A downlink control channel 1800 including resource allocation information may be transmitted, and a downlink control channel set #2 composed of a plurality of downlink control channels including resource allocation information of a downlink data channel may be transmitted. . Downlink control channel set #1 may be transmitted before the downlink control channel 1800, and downlink control channel set #2 may be transmitted after the downlink control channel 1800. A case in which the uplink control channel is repeatedly transmitted 4 times and the uplink data channel is repeatedly transmitted 4 times is considered. In FIG. 18, downlink control channel set #1 and downlink control channel set #2 are each of downlink control channel set #1 and downlink control channel set #2 so that the uplink control channel is transmitted in slot #1. It is assumed that the downlink control channel instructs the UE. In this case, the uplink control channel may be repeatedly transmitted 4 times in slot #1 to slot #4. On the other hand, the downlink control channel 1800 instructs the terminal to transmit the uplink data channel in slot #3. In this case, if transmission is repeated four times, the uplink data channel may be repeatedly transmitted four times in slot #3 to slot #6.

The serving base station can know the size of the HARQ response (hereinafter referred to as "HARQ response #1") for the downlink data channels scheduled by the downlink control channel set #1.

When transmitted through the uplink data channel 1810 scheduled by the downlink control channel 1800, since the serving base station already knows the amount of HARQ response #1, the uplink data channel 1810 by HARQ response #1 ), resources of the uplink data channel 1810 may be allocated in consideration of puncturing or rate matching.

The UE may receive downlink data channels in resources indicated by downlink control channel set #2, and generate an HARQ response (hereinafter referred to as “HARQ response #2”) to the received downlink data channels. can be generated, and an encoding operation can be performed on the generated HARQ response #2. At this time, if HARQ response #1 exists, since slots transmitting the uplink control channel are identically overlapped, encoding can be performed including both HARQ response #1 and HARQ response #2. Since the downlink control channel set #2 is transmitted after the downlink control channel 1800, the base station transmits the downlink control channel 1800 for allocating resources of the uplink data channel 1810. I don't know how much On the other hand, as described above, if HARQ response #1 exists, the base station may allocate resources of an uplink data channel considering the amount of HARQ response #1 to the UE.

We propose a method in which the terminal transmits HARQ response #1 and HARQ response #2 in the same slot #1 in the uplink control channel according to the instruction of the base station. The serving base station must perform resource allocation in which the uplink data channel 1810 considers HARQ response #1 in slot #3 and slot #4, but cannot consider HARQ response #2. In this case, in order to minimize performance degradation of the uplink data channel 1810 due to HARQ response #2, an operation of reducing the amount of HARQ response #2 may be defined. The UE may perform compression on HARQ response #2. For example, the terminal may generate a 1-bit or 2-bit HARQ response by performing a logical AND operation on HARQ response #2. This can be applied to both the case of generating HARQ for each TB and the case of generating HARQ for each CBg in downlink control channel set #2.

When HARQ response #1 is transmitted through the uplink data channel 1810 indicated by the downlink control channel 1800 (ie, when HRAQ response #2 is not transmitted), the UE considers HARQ response #1 Thus, rate matching for the uplink data channel 1810 can be performed. Alternatively, when HARQ response #1 and HARQ response #2 are transmitted through the uplink data channel 1810 indicated by the downlink control channel 1800, the UE considers the HARQ response #1 and uses the uplink data channel ( 1810), and puncturing the uplink data channel 1810 for transmission of HARQ response #2.

■ How to configure various payloads

In the embodiment below, repeated transmission of HARQ response #2 on downlink data channel #2 is performed before repeated transmission of HARQ response #1 on downlink data channel #1 is completed, and HARQ response #1 and HARQ response #2 A method of configuring an uplink channel (eg, uplink payload) when the slots in which each repetitive transmission starts is different from each other will be described. Here, the amount of resources possessed by the uplink channel may be set variably for each slot.

Referring back to FIG. 13, the base station can transmit downlink data channel #1 in slot #n and transmit downlink data channel #2 in slot #(n+2). The UE may receive downlink data channel #1 in slot #n, and transmit HARQ response #1 (ie, uplink control channel #1) to the downlink data channel #1 in slots #(n+4) to #. It can be repeatedly transmitted 4 times at (n + 7). The UE may receive downlink data channel #2 in slot #(n+2), and transmit HARQ response #2 (ie, uplink control channel #2) to the downlink data channel #2 in slot #(n+2). 5) to #(n+8) can be repeatedly transmitted 4 times.

Here, the terminal may generate m-bit HARQ response #1 and may generate m'-bit HARQ response #2. The UE determines m and m' based on a function of the number of CBg and activated DL CCs obtained through "uplink signaling procedure" or "combination of uplink signaling procedure and downlink control channel transmission procedure" can The terminal may determine the size of the HARQ response codebook for slot #(n+4) as m bits, and the size of the HARQ response codebook for slots #(n+5) to #(n+7) as m+m' bits. It can be determined, and the size of the HARQ response codebook for slot # (n + 8) can be determined as m' bits.

The UE may perform encoding for the HARQ response codebook using a single uplink control channel format (eg, NR PUCCH format 3) or a plurality of uplink control channel formats according to the configuration of the base station. When a single format is used, each of the m bits, m+m' bits, and m' bits may have a size supported by the single format (eg, a sufficient number of symbols or a sufficient amount of resource blocks). When a plurality of formats are used, the terminal can select an appropriate format according to the size of the HARQ response codebook. For example, the UE may use format A (eg, NR PUCCH format 0) when the size of the HARQ response codebook is 1 bit, and format B (eg, format B when the size of the HARQ response codebook is 2 bits) For example, NR PUCCH format 1) can be used, and format C (eg, NR PUCCH format 2 or format 3 or format 4) can be used when the size of the HARQ response codebook is 3 bits or more. As another example, format D (eg, LTE PUCCH format 1 or format 1a or format 1b) can be used when the size of the HARQ response codebook is 1 to 2 bits, and the size of the HARQ response codebook is 3 to 4 bits. In this case, format E having channel selection (eg, LTE PUCCH format 1b with channel selection) can be used, and when the size of the HARQ response codebook is 3 to 21 bits, format F (eg, LTE PUCCH format 3) can be used, and format G (eg, LTE PUCCH format 4 or format 5) can be used when the size of the HARQ response codebook is 22 bits or more.

■ How fixed payloads are constructed

In the embodiment below, when repeated transmission of HARQ response #2 for downlink data channel #2 is performed before repeated transmission of HARQ response #1 for downlink data channel #1 is completed, an uplink channel (eg, For example, a method of constructing an uplink payload) will be described. Here, the size of the HARQ response codebook transmitted through the uplink channel may not be changed.

The base station may inform the terminal of the transmission timing of the HARQ response for the downlink data channel together with the resource allocation information of the downlink data channel. For example, the base station may inform the terminal of the transmission timing set of the HARQ response through a higher layer signaling procedure, and the transmission timing set of the HARQ response is selected through the downlink data channel used for scheduling of the downlink data channel. Transmission timing of one HARQ response may be informed to the UE. The signaling method of the transmission timing of the HARQ response can be applied to both slot-based scheduling and subslot-based scheduling with different downlink data channel intervals.

Therefore, the base station may adjust the transmission timing of the HARQ response for the downlink data channel to maintain the same size of the HARQ response codebook as in the embodiment shown in FIG. 19 below.

19 is a timing diagram illustrating a sixth embodiment of a method of transmitting an uplink channel in a communication system.

In FIG. 19, a DL slot means a slot capable of transmitting a downlink data channel, and may not necessarily mean a downlink slot or a downlink-centric slot. In FIG. 19, a UL slot means a slot capable of transmitting an uplink control channel, and may not necessarily mean an uplink slot or an uplink-centric slot.

Referring to FIG. 19, a base station may transmit a downlink data channel to a terminal, and upon receiving the downlink data channel, the terminal repeats a HARQ response (eg, an uplink control channel) for the downlink data channel four times. can transmit The transmission timing of the HARQ response (ie, the first position of the UL slot in which the HARQ response is transmitted) may be indicated by a downlink control channel used for scheduling of the corresponding downlink data channel.

For example, the base station transmits resource allocation information (eg, DL slot #n) of downlink data channel #1 and transmission timing of HARQ response #1 for downlink data channel #1 (eg, UL slot # (n + 4)), resource allocation information (eg, DL slot # (n + 1)) of downlink data channel # 2 and downlink data channel # 2 A downlink control channel including transmission timing of HARQ response #2 (eg, UL slot #(n+8)) may be transmitted. Upon receiving the downlink control channel, the UE can check the resource allocation information of the downlink data channel and transmission timing of the HARQ response for the corresponding downlink data channel.

In this case, the base station can transmit downlink data channel #1 in DL slot #n, and the terminal receiving downlink data channel #1 responds to HARQ in UL slots #(n+4) to #(n+7) #1 can be repeated 4 times. In addition, the base station may transmit downlink data channel #2 in DL slot #(n + 1), and the terminal receiving the downlink data channel # 2 may transmit UL slots # (n + 8) to # (n + 11) HARQ response #2 can be repeatedly transmitted 4 times. Therefore, the size of the HARQ response codebook can be kept the same in UL slots #(n+4) to #(n+11).

The above-described embodiment can be applied to a communication system supporting a plurality of numerologies (for example, when a numerology of a DL slot is different from a numerology of a UL slot), a communication system supporting TDD, and the like. there is. The base station can schedule a downlink data channel even when repeated transmission of the HARQ response is not completed by informing the terminal of the transmission timing of the appropriate HARQ response.

Alternatively, the base station may not inform the terminal of the transmission timing of the HARQ response using a separate downlink control channel. In this case, since the UE already knows the number (k) of repeated transmissions of the uplink control channel, it selects the earliest UL slots (or UL-centric slots) among available UL slots (or UL-centric slots). HARQ response can be transmitted using

The minimum processing time of the downlink data channel (eg, minimum processing time required for generating/transmitting an HARQ response for the downlink data channel) may be set by a higher layer signaling procedure. Alternatively, the minimum processing time of the downlink data channel may be predefined in the 3GPP TS. In this case, there may be k DL slots (or DL-centric slots) corresponding to k UL slots (or UL-centric slots) used for repeated transmission of the HARQ response.

■ Soft combining action

The UE may transmit uplink control information (UCI) having different redundancy versions (RVs). Here, the uplink control information may be a HARQ response codebook to which a polar code is applied. When the new HARQ response bits are encoded, the UE may newly derive RV of uplink control information including the encoded HARQ response bits.

Referring back to FIG. 13, when there is no new HARQ response bit, the UE may transmit uplink control information in the order of "RV a → RV b → RV c → RV d". In slot #(n+4), the terminal may perform an encoding operation on m-bit HARQ response #1 and may transmit RV a of uplink control information including encoded m bits. In slot #(n+5), the terminal may perform an encoding operation on "m-bit HARQ response #1 + m'-bit HARQ response #2", and upstream including encoded m+m' bits. RV a of link control information may be transmitted. In slot #(n+6), the terminal may transmit RV b of uplink control information including coded m+m' bits, and in slot #(n+7), the terminal transmits coded m+m' bits. RV c of the included uplink control information may be transmitted. In slot #(n+8), the terminal may perform an encoding operation on HARQ response #2 of m' bits and may transmit RV a of uplink control information including coded m' bits.

The methods according to the present invention may be implemented in the form of program instructions that can be executed by various computer means and recorded on a computer readable medium. Computer readable media may include program instructions, data files, data structures, etc. alone or in combination. Program instructions recorded on a computer readable medium may be specially designed and configured for the present invention or may be known and usable to those skilled in computer software.

Examples of computer readable media include hardware devices specially configured to store and execute program instructions, such as ROM, RAM, flash memory, and the like. Examples of program instructions include high-level language codes that can be executed by a computer using an interpreter or the like as well as machine language codes generated by a compiler. The hardware device described above may be configured to operate with at least one software module to perform the operations of the present invention, and vice versa.

Although described with reference to the above embodiments, those skilled in the art will understand that the present invention can be variously modified and changed without departing from the spirit and scope of the present invention described in the claims below. You will be able to.

Claims (20)

As a method of operating a user equipment (UE) in a communication system,
Receiving setting information indicating a slot format through higher layer signaling;
Receiving information on the number of repetitions (N) of physical uplink control channel (PUCCH) transmission through the higher layer signaling; and
Transmitting PUCCH N times using slots determined based on the configuration information and the number of repetitions (N);
The slot format is a configuration of DL (downlink)-UL (uplink) symbols in each slot. The method of claim 1,
If one slot among N consecutive slots is not used for PUCCH transmission according to the configuration information, an available slot corresponding to the configuration information after the N consecutive slots is used for PUCCH transmission. , The determined slots are "the consecutive N slots-the one slot" + "the usable slot", the operating method of the UE. The method of claim 1,
The PUCCH is transmitted based on a frequency hopping method. delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete

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