KR20190038983A - Apparatus and method of multiplexing of multiple uplink control information for new radio - Google Patents

Abstract

The present invention relates to a transmission and reception method of uplink control information in a next generation/5G wireless access network. According to an embodiment of the present invention, in the transmission and reception method of uplink control information in a next generation/5G wireless access network, a base station sets a HARQ ACK/NACK feedback mode for each terminal.

Description

[0001] The present invention relates to a method and an apparatus for multiplexing a plurality of uplink control information for a next generation wireless network,

The present invention proposes a method for transmitting / receiving uplink control information in a next generation / 5G radio access network (hereinafter referred to as NR (New Radio) in the present invention).

A method of transmitting / receiving uplink control information in a next generation / 5G radio access network according to an embodiment of the present invention is characterized in that a base station sets a HARQ ACK / NACK feedback mode for each UE.

FIG. 1 illustrates an example of symbol level alignment among different SCSs.
2 is a conceptual illustration of a Bandwidth part.
3 is a diagram illustrating Ambiguity on PUCCH resource determination.
4 is a diagram illustrating a configuration of a base station according to another embodiment of the present invention.
5 is a diagram illustrating a configuration of a user terminal according to another embodiment of the present invention.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. It should be noted that, in adding reference numerals to the constituent elements of the drawings, the same constituent elements are denoted by the same reference symbols as possible even if they are shown in different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

As used herein, a wireless communication system refers to a system for providing various communication services such as voice, packet data, and the like. A wireless communication system includes a user equipment (UE) and a base station (BS).

The user terminal is a comprehensive concept that means a terminal in a wireless communication, and it is a comprehensive concept which means a mobile station (MS) in GSM, a mobile station (MS) in UT (User Terminal), a Subscriber Station (SS), a wireless device, and the like.

A base station or a cell generally refers to a station that communicates with a user terminal and includes a Node-B, an evolved Node-B, a gNode-B, a Low Power Node A sector, a site, various types of antennas, a base transceiver system (BTS), an access point, a point (for example, a transmission point, a reception point, a transmission / reception point) (RRH), a radio unit (RU), and a small cell, as well as a relay cell, a relay node, a megacell, a macrocell, a microcell, a picocell, a femtocell, an RRH,

Since the various cells listed above exist in the base station controlling each cell, the base station can be interpreted into two meanings. Macro cell, micro cell, picocell, femtocell, small cell, or 2) the wireless region itself in connection with the wireless region. 1), all of the devices that interact to configure the wireless area to be cooperatively controlled by the same entity are all pointed to the base station. A point, a transmission / reception point, a transmission point, a reception point, and the like are examples of the base station according to the configuration method of the radio area. 2 may direct the base station to the wireless region itself to receive or transmit signals at the point of view of the user terminal or in the vicinity of the neighboring base station.

In this specification, a cell refers to a component carrier having a coverage of a signal transmitted from a transmission point or a transmission point or a transmission point or a transmission / reception point of a signal transmitted from a transmission / reception point, and a transmission / reception point itself .

Herein, the user terminal and the base station are used in a broad sense as two (uplink or downlink) transmitting and receiving subjects used to implement the technology or technical idea described in the present invention, and are not limited by a specific term or word Do not.

Here, an uplink (UL, or uplink) means a method of transmitting / receiving data to / from a base station by a user terminal, and a downlink (DL or downlink) .

The time division duplex (TDD) scheme, which is transmitted using different time periods, can be used for the uplink and downlink transmission, and a frequency division duplex (FDD) scheme in which different frequencies are used, a TDD scheme and an FDD scheme A hybrid method can be used.

In the wireless communication system, the uplink and the downlink are configured with reference to one carrier or carrier pair to form a standard.

The uplink and the downlink transmit control information through a control channel such as a physical downlink control channel (PDCCH), a physical uplink control channel (PUCCH), and the like. The physical downlink shared channel (PDSCH), the physical uplink shared channel (PUSCH) It is composed of the same data channel and transmits data.

A downlink may refer to a communication or communication path from a multipoint transmission / reception point to a terminal, and an uplink may refer to a communication or communication path from a terminal to a multiple transmission / reception point. At this time, in the downlink, the transmitter may be a part of the multiple transmission / reception points, and the receiver may be a part of the terminal. Also, in the uplink, the transmitter may be a part of the terminal, and the receiver may be a part of multiple transmission / reception points.

Hereinafter, a situation in which a signal is transmitted / received through a channel such as PUCCH, PUSCH, PDCCH, and PDSCH is expressed as 'PUCCH, PUSCH, PDCCH and PDSCH are transmitted and received'.

Meanwhile, the High Layer Signaling described below includes RRC signaling for transmitting RRC information including RRC parameters.

The base station performs downlink transmission to the UEs. The base station includes downlink control information, such as scheduling, required for reception of a downlink data channel, which is a primary physical channel for unicast transmission, and physical downlink control information for transmitting scheduling grant information for transmission in an uplink data channel. A control channel can be transmitted. Hereinafter, the transmission / reception of a signal through each channel will be described in a form in which the corresponding channel is transmitted / received.

There are no restrictions on multiple access schemes applied in wireless communication systems. (TDMA), Frequency Division Multiple Access (FDMA), Code Division Multiple Access (CDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Non-Orthogonal Multiple Access (NOMA) Various multiple access schemes such as OFDM-CDMA can be used. Here, the NOMA includes Sparse Code Multiple Access (SCMA) and Low Density Spreading (LDS).

One embodiment of the present invention relates to asynchronous wireless communications that evolve into LTE / LTE-Advanced, IMT-2020 over GSM, WCDMA, HSPA, and synchronous wireless communications such as CDMA, CDMA- Can be applied.

In this specification, a MTC (Machine Type Communication) terminal may mean a terminal supporting low cost (or low complexity) or a terminal supporting coverage enhancement. Alternatively, the MTC terminal may refer to a terminal defined in a specific category for supporting low cost (or low complexity) and / or coverage enhancement.

In other words, the MTC terminal in this specification may mean a newly defined 3GPP Release-13 low cost (or low complexity) UE category / type for performing LTE-based MTC-related operations. Alternatively, the MTC terminal may support enhanced coverage over the existing LTE coverage or a UE category / type defined in the existing 3GPP Release-12 or lower that supports low power consumption, or a newly defined Release-13 low cost low complexity UE category / type. Or a further Enhanced MTC terminal defined in Release-14.

In this specification, NarrowBand Internet of Things (NB-IoT) terminal means a terminal supporting wireless access for cellular IoT. The objectives of NB-IoT technology include improved indoor coverage, support for large-scale low-rate terminals, low latency sensitivity, ultra-low cost, low power consumption, and optimized network architecture.

Enhanced Mobile Broadband (eMBB), massive Machine Type Communication (mMTC), and Ultra Reliable and Low Latency Communication (URLLC) have been proposed as typical usage scenarios in NR (New Radio), which is under discussion in 3GPP.

In this specification, a frequency, a frame, a subframe, a resource, a resource block, a region, a band, a subband, a control channel, a data channel, a synchronization signal, various reference signals, various signals, May be interpreted as past or presently used meanings or various meanings used in the future.

NR (New Radio)

3GPP recently approved a study item "Study on New Radio Access Technology" for research on next generation radio access technology (ie 5G radio access technology), and based on this, RAN WG1 has a frame structure , channel coding & modulation, waveform & multiple access schemes, and so on. NR is required not only to improve data transmission rate as compared with LTE, but also to design various QoS requirements that are required according to granular and specific usage scenarios. In particular, enhancement mobile broadband (eMBB), massive MTC (MMTC) and URLLC (Ultra Reliable and Low Latency Communications) are defined as typical usage scenarios of NR. structure design is required. Since each usage scenario has different requirements for data rates, latency, reliability, coverage, etc., it is a method to efficiently satisfy the requirements of each usage scenario through frequency bands constituting an NR system. there is a need for an efficient multiplexing of radio resource units based on subcarrier spacing, subframe, TTI, etc., for example.

One method is to support TDM, FDM or TDM / FDM based multiplexing on one or more NR component carriers (s) for numerology with different subcarrier spacing values, and a scheduling unit in the time domain A discussion was made on how to support more than one time unit in composition. In this regard, NR is a type of time domain structure defined as a subframe. Reference numerology for defining the subframe duration is defined as 14 OFDM symbols of 15 kHz sub-carrier spacing (SCS) based normal CP overhead equivalent to LTE To define a single subframe duration. Thus, subframes in NR have a time duration of 1ms. However, unlike LTE, NR subframes are absolute reference time durations, and slots and mini-slots can be defined as time units that are the basis of actual uplink and downlink data scheduling. In this case, the number of OFDM symbols constituting the slot and the y-value are determined to have a value of y = 14 regardless of the SCS value in the normal CP.

Therefore, any slot is composed of 14 symbols, and all symbols are used for DL transmission according to the transmission direction of the slot, or all symbols are used for UL transmission, or DL portion + (gap) + Can be used in the form of a UL portion.

Also, a mini-slot composed of fewer symbols than the slot is defined in an arbitrary numerology (or SCS), and a short-time time-domain scheduling interval for transmitting / receiving uplink / downlink data is set based on the mini- A long-time time-domain scheduling interval for uplink / downlink data transmission and reception can be configured. Especially, in case of transmission and reception of latency critical data such as URLLC, scheduling is performed in 1 ms (14 symbols) -based slot unit defined in a numerology-based frame structure having a small SCS value such as 15 kHz, it is difficult to satisfy the latency requirement Therefore, it is possible to define a mini-slot composed of a fewer number of OFDM symbols than the corresponding slot and to schedule the latency critical data such as the URLLC based on the defined mini-slot.

Alternatively, as described above, by supporting the numerology having different SCS values in one NR Carrier by multiplexing the TDM and / or FDM scheme, it is possible to reduce the number of slots based on the slot (or mini-slot) length defined for each numerology Scheduling of data according to latency requirement is also considered. For example, as shown in FIG. 1, when the SCS is 60 kHz, the symbol length is reduced to about 1/4 of that of the SCS 15 kHz. Therefore, when one slot is composed of 14 OFDM symbols, The length is 1ms, while the slot length based on 60kHz is reduced to about 0.25ms.

In this way, the NR is discussing how to satisfy the requirements of URLLC and eMBB by defining different SCSs or different TTI lengths.

Wider bandwidth operations

For existing LTE systems, scalable bandwidth operation for arbitrary LTC Component Carriers (CCs) was supported. That is, according to the frequency deployment scenario, an arbitrary LTE provider can configure a bandwidth from 1.4 MHz to a maximum of 20 MHz in configuring one LTE CC, and a normal LTE terminal can configure a bandwidth of 20 MHz for one LTE CC Transmission / reception capability.

However, in the case of NR, a design is made to support NR terminals having different transmission and reception bandwidth capabilities through one wideband NR CC. Accordingly, as shown in FIG. 2, It is required to configure at least one bandwidth part (s) composed of the bandwidth and to support the wider bandwidth operation by the different bandwidth part configuration and activation for each terminal.

Specifically, in NR, one or more bandwidth parts can be configured through one serving cell configured from a terminal perspective, and the terminal activates one DL bandwidth part and one UL bandwidth part in the corresponding serving cell to transmit uplink data It is defined for use for sending and receiving. Also, when a plurality of serving cells are set in the corresponding terminal, that is, for a terminal to which the CA is applied, one DL bandwidth part and / or an UL bandwidth part is activated for each serving cell, and the up / Link data transmission and reception.

Specifically, an initial bandwidth part for an initial access procedure of a UE is defined in an arbitrary serving cell, one or more UE-specific bandwidth part (s) is configured by dedicated RRC signaling for each UE, and a fallback A default bandwidth part for operation can be defined.

However, it is possible to define multiple DL and / or UL bandwidth parts to be used simultaneously according to the capability and bandwidth part (s) configuration of a UE in an arbitrary serving cell. In NR rel-15, It is defined to activate only one DL bandwidth part and UL bandwidth part at a time.

NR PUCCH

In the conventional LTE system, the uplink control channel (PUCCH) transmission for uplink control information (UCI) of the UE is performed on a single subframe basis. That is, one PUCCH transmission is performed on 14 SC-FDMA symbols constituting one subframe in the time-domain. However, when the last symbol is used for SRS transmission, PUCCH transmission is performed through 13 symbols except for the last symbol.

Different PUCCH formats are defined according to the UCI payload size. Specifically, UCI transmission of 1 or 2 bits such as SR (Scheduling Request) and HARQ ACK is transmitted through a PUCCH format 1 (PUCCH format 1 / 1a / 1b) and has a moderate payload size such as CQI / CSI feedback UCI is defined to use PUCCH format 2 (PUCCH format 2a / 2b) series, and PUCCH format 3 or more for UCI feedback of large payload size in CA situations.

However, in the case of NR, a PUCCH structure with various durations is defined within a slot consisting of 14 symbols. Specifically, a long PUCCH is divided into a long-PUCCH and a long-PUCCH according to the number of symbols and N values of a single PUCCH transmission in one slot. The long-PUCCH is transmitted through 4 to 14 symbols in one slot And in case of a short-PUCCH, it can be transmitted through one to two symbols. Different PUCCH formats can be defined similar to LTE according to the UCI payload size for each long-PUCCH and short-PUCCH. For example, a PUCCH format for up-to-2-bit UCI transmission and a PUCCH format for UCI transmission having a payload size of up to 2 bits are defined for the short-PUCCH, and a UCI A PUCCH format for transmission and a PUCCH format for UCI transmission having a payload size larger than that can be respectively defined.

That is, the definition of the PUCCH duration and the PUCCH format may be required in defining the PUCCH structure for UCI transmission in the NR.

In the present invention, when a plurality of UCIs are transmitted through a single slot in an arbitrary terminal, when a plurality of PUCCH resources are set for each UCI in the corresponding slot, the plurality of UCIs are multiplexed through one PUCCH And the like.

In NR, it is possible to dynamically set the HARQ ACK / NACK feedback timing of the UE for the PDSCH transmission for an arbitrary UE through the DL assignment DCI, unlike LTE. In addition, the aperiodic CSI reporting information of the UE can be transmitted through an arbitrary slot according to the configuration of the BS.

Accordingly, HARQ ACK / NACK feedback for different PDSCH transmissions can be indicated by the BS through the same slot as shown in FIG. 3 below. In particular, a separate PUCCH resource for HARQ ACK / NACK feedback for each PDSCH transmission If allocation is made, it is necessary to define the specific PUCCH transmission method of the UE in the corresponding slot.

That is, as shown in FIG. 3, in the first PDSCH transmission by the first DL assignment DCI, the second PDSCH transmission by the second DL assignment DCI, and the third PDSCH transmission by the third DL assignment DCI, HARQ ACK / NACK feedback is indicated through the same slot for the first slot, and a first PUCCH for each HARQ ACK / NACK feedback through the first DL assignment DCI, the second DL assignment DCI, and the third DL assignment DCI, PUCCH, and the third PUCCH allocation is performed, it is necessary to define a specific method for HARQ ACK / NACK feedback at the corresponding terminal.

Point 1: HARQ ACK / NACK  Setting the multiplexing mode

The base station may define a HARQ ACK / NACK feedback mode for each UE. The corresponding HARQ ACK / NACK feedback mode defines an operation of generating HARQ ACK / NACK feedback information at the UE when HARQ ACK / NACK feedback of the UE for multiple PDSCH reception is indicated through one slot as described above . For example, a bundling mode and a multiplexing mode may be defined as HARQ ACK / NACK feedback modes of the UE. When a UE set in a bundling mode is instructed to perform HARQ ACK feedback through a single slot for a plurality of PDSCH reception as shown in FIG. 3, the UE sets bundled ACK / NACK feedback information for the plurality of PDSCHs through a single PUCCH resource . For example, if TB-based HARQ-ACK feedback is set for an arbitrary UE set in the bundling mode, the UE feeds back the ACK only when all TBs received on the plurality of PDSCHs are successfully decoded, In all cases (that is, if an error occurs even with one TB), you can define NACK to be fed back. In the case of a UE set in a multiplexing mode, HARQ ACK / NACK feedback information for each PDSCH is multiplexed and transmitted. For example, if TB-based HARQ-ACK feedback is set for an arbitrary UE set in a multiplexing mode, the corresponding UE generates HARQ ACK / NACK feedback information for all TBs received on the plurality of PDSCHs, Can be defined.

3, if one TB is transmitted per PDSCH, a TB-based (re) transmission mode is set, and a bundling mode is set as a HARQ ACK / NACK multiplexing mode of the corresponding UE, a 1-bit ACK / NACK Information is fed back through the slot # (n + k). When the multiplexing mode is set, 3 bits of ACK / NACK information are fed back through the slot # (n + k).

At this time, the HARQ ACK / NACK multiplexing mode can be established by a base station through UE-specific higher layer signaling, MAC CE signaling, or L1 control signaling for each UE.

Point 2: simultaneous PUCCH  transmission setting

In a case where a plurality of PUCCHs are instructed to be transmitted through one slot in an arbitrary terminal, transmission support for the plurality of PUCCHs can be defined to be configurable for each terminal. That is, it can be set for simultaneous PUCCH transmission. When a simultaneous PUCCH transmission is set for an arbitrary UE, if a plurality of PUCCH resources are allocated for each UCI transmission through a certain slot, the UE transmits each UCI individually through each PUCCH Lt; / RTI > In addition, when configuring simultaneous PUCCH transmission, it can be defined that the maximum number of PUCCH transmissions that can be transmitted through a single slot in the corresponding terminal is set. Alternatively, the corresponding setting may be a setting for supporting transmission of a plurality of UL physical channels through a single slot of one serving cell in an arbitrary UE regardless of PUCCH and PUSCH in a simultaneous UL transmission setting. In this case as well, the maximum number of UL physical channel transmissions commonly applicable to the PUCCH and the PUSCH may be additionally set through a single slot.

Simultaneous PUCCH transmission, simultaneous UL transmission, number of simultaneous PUCCH transmission, or number of simultaneous UL transmission information are set in the base station and are defined to transmit by UE-specific higher layer signaling, MAC CE signaling or L1 control signaling for each terminal can do.

Point 3: determination of PUCCH  resource

When a plurality of UCI transmissions are directed through a single slot in an arbitrary terminal and the PUCCH resource for each UCI transmission is indicated by a different signaling from a base station, a single PUCCH resource among the indicated PUCCH resources Or by multiplexing or bundling the UCIs. For example, as shown in FIG. 3 of point 1, different PDSCH scheduling and PUCCH resource allocation information for HARQ ACK feedback of a UE for each PDSCH are transmitted through different DL assignment DCI messages for an arbitrary UE. The UE may select one PUCCH resource among the allocated PUCCH resources and transmit corresponding HARQ ACK feedback information (eg, bundled ACK / NACK information or multiplexed ACK / NACK information).

In this case, as a method of selecting the PUCCH resource, it is possible to define that the corresponding UE transmits the corresponding UCI (s) through the PUCCH resource allocated through signaling received from the base station most recently. That is, in the case of FIG. 3, the UE may transmit the corresponding HARQ ACK / NACK feedback information (e.g., bundled ACK / NACK or multiplexed ACK / NACK) through the third PUCCH.

Specifically, allocation is made by a second DL assignment DCI format including resource allocation information for a second PDSCH and a first PUCCH resource allocated by a first DL assignment DCI format including resource allocation information for the first PDSCH If the third PUCCH resource allocated by the third DL assignment DCI format including the allocated second PUCCH resource and the resource allocation information for the third PDSCH is allocated through the same slot as described above, And to transmit HARQ ACK / NACK feedback information for the first, second, and third PDSCH reception on the third PUCCH allocated by the DL assignment DCI format. However, when a plurality of DL assignment DCIs are transmitted through the same slot, specifically, PDSCH resource allocation information for a plurality of different serving cells is transmitted through one slot or a plurality of PDCCH CORESETs And a PDCCH monitoring occasion corresponding to the PDCCH monitoring occasion is configured, a method of determining a DL assignment DCI format transmitted at the last is to index the corresponding DL assignment DCI format in order of a cell index, And the HARQ ACK / NACK feedback for the corresponding PDSCH reception is transmitted through the PUCCH resource allocated by the last DL assignment DCI format (i.e., the highest index DL assignment DCI format) based on the index assignment Can be defined. Alternatively, the PDCCH monitoring occasion index is firstly indexed in the order of the DL assignment DCI format, followed by indexing the corresponding DL assignment DCI format in the order of the cell index, and based on this, the corresponding DL assignment DCI format It is possible to define that the HARQ ACK / NACK feedback for the PDSCH reception is transmitted through the PUCCH resource allocated by the DL index DCI format of the high index.

As another method, when the PUCCH resource is allocated by the base station, it may be defined to indicate whether the PUCCH resource is a priority PUCCH resource in the corresponding slot. The PUCCH resource indicated by the priority PUCCH may be information indicating that it is a PUCCH resource to be preferentially transmitted in a case where a plurality of PUCCH resources are allocated in the corresponding slot. For example, in the case of FIG. 3, the BS may indicate whether the corresponding PUCCH allocation is a priority PUCCH allocation through a priority setting bit for each PUCCH allocation when the PUCCH resource is allocated through the DL assignment DCI, Accordingly, it is possible to indicate the PUCCH to be used by the UE among the first, second, and third PUCCHs. For example, when the base station designates the first PUCCH allocation as a priority PUCCH allocation when allocating the first PUCCH resource through the first DL assignment DCI, the UE transmits corresponding HARQ ACK / NACK feedback information (eg, a bundled ACK / NACK or a multiplexed ACK / NACK).

However, when a plurality of DL assignment DCI formats and a PUCCH resource for HARQ ACK / NACK feedback of a UE for PDSCH reception according to the DCI format are performed through the same slot, among the plurality of PUCCH resources allocated in the corresponding slot, The PUCCH resources are not overlapped with other PUCCH resources in the time slot (i.e., no PUCCH transmission resource allocation is performed in a symbol to which the PUCCH resource is allocated), and the PUCCH resource determination method And the HARQ ACK / NACK feedback transmission of the UE through the PUCCH can be defined to be performed independently. That is, the PUCCH determination rule can be defined to be applied only to PUCCH resources partially or fully overlapped in the time domain among a plurality of PUCCH resources allocated through one slot. The HARQ ACK / NACK feedback of the UE for all PUCCH resources allocated through the same slot can be defined to apply the PUCCH determination rule for transmission irrespective of overlap in time domain.

4 is a diagram illustrating a configuration of a base station 1000 according to another embodiment of the present invention.

Referring to FIG. 4, a base station 1000 according to another embodiment includes a control unit 1010, a transmission unit 1020, and a reception unit 1030.

The control unit 1010 is a method for transmitting / receiving uplink control information in a next generation / 5G radio access network required for performing the present invention, wherein a base station sets a HARQ ACK / NACK feedback mode for each UE And controls the operation of the base station 1000 as a whole.

The transmitting unit 1020 and the receiving unit 1030 are used to transmit and receive signals, messages, and data necessary for carrying out the present invention to and from the terminal.

5 is a diagram illustrating a configuration of a user terminal 1100 according to another embodiment of the present invention.

5, the user terminal 1100 according to another embodiment includes a receiving unit 1110, a control unit 1120, and a transmitting unit 1130.

The receiving unit 1110 receives downlink control information, data, and messages from the base station through the corresponding channel.

Also, the controller 1120 is configured to set up a HARQ ACK / NACK feedback mode for each UE in a method for transmitting and receiving uplink control information in a next generation / 5G radio access network required to perform the present invention, And controls the operation of the overall user terminal 1100 according to the type of the user terminal 1100.

The transmitter 1130 transmits uplink control information, data, and a message to the base station through the corresponding channel.

The standard content or standard documents referred to in the above-mentioned embodiments constitute a part of this specification, for the sake of simplicity of description of the specification. Therefore, it is to be understood that the content of the above standard content and portions of the standard documents are added to or contained in the scope of the present invention.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

Claims (1)

A method for transmitting / receiving uplink control information in a next generation / 5G radio access network,
Wherein the base station sets an HARQ ACK / NACK feedback mode for each UE.

Images