KR102532301B1 - Method and apparatus for determination of downlink control information in wirelss communication system - Google Patents

Abstract

The present disclosure relates to a method for setting downlink control information in a wireless communication system, which transmits bandwidth portion setting information to a terminal and determines the size of downlink control information (DCI) through the bandwidth portion setting information. and may transmit a DCI corresponding to the determined size to the terminal.

Description

Method and apparatus for setting downlink control information in wireless communication system {METHOD AND APPARATUS FOR DETERMINATION OF DOWNLINK CONTROL INFORMATION IN WIRELSS COMMUNICATION SYSTEM}

The present invention relates to a wireless communication system, and relates to a method and apparatus for smoothly providing a service in a wireless communication system. More specifically, it relates to a method and apparatus for setting downlink control information in a wireless communication system.

Efforts are being made to develop an improved 5G communication system or pre-5G communication system to meet the growing demand for wireless data traffic after the commercialization of the 4G communication system. For this reason, the 5G communication system or pre-5G communication system is being called a system after a 4G network (Beyond 4G Network) communication system or an LTE system (Post LTE). In order to achieve a high data rate, the 5G communication system is being considered for implementation in a mmWave band (eg, a 60 gigabyte (70 GHz) band). In order to mitigate the path loss of radio waves and increase the propagation distance of radio waves in the ultra-high frequency band, beamforming, massive MIMO, and Full Dimensional MIMO (FD-MIMO) are used in 5G communication systems. ), array antenna, analog beam-forming, and large scale antenna technologies are being discussed. In addition, to improve the network of the system, in the 5G communication system, an evolved small cell, an advanced small cell, a cloud radio access network (cloud RAN), and an ultra-dense network , Device to Device communication (D2D), wireless backhaul, moving network, cooperative communication, Coordinated Multi-Points (CoMP), and interference cancellation etc. are being developed. In addition, in the 5G system, advanced coding modulation (Advanced Coding Modulation: ACM) methods FQAM (Hybrid FSK and QAM Modulation) and SWSC (Sliding Window Superposition Coding), advanced access technologies FBMC (Filter Bank Multi Carrier), NOMA (non-orthogonal multiple access), SCMA (sparse code multiple access), and the like are being developed.

On the other hand, the Internet is evolving from a human-centered connection network in which humans create and consume information to an Internet of Things (IoT) network in which information is exchanged and processed between distributed components such as things. IoE (Internet of Everything) technology, which combines IoT technology with big data processing technology through connection with a cloud server, etc., is also emerging. In order to implement IoT, technical elements such as sensing technology, wired/wireless communication and network infrastructure, service interface technology, and security technology are required, and recently, sensor networks for connection between objects and machine to machine , M2M), and MTC (Machine Type Communication) technologies are being studied. In the IoT environment, intelligent IT (Internet Technology) services that create new values in human life by collecting and analyzing data generated from connected objects can be provided. IoT is a field of smart home, smart building, smart city, smart car or connected car, smart grid, health care, smart home appliances, advanced medical service, etc. can be applied to

Accordingly, various attempts are being made to apply the 5G communication system to the IoT network. For example, technologies such as sensor network, machine to machine (M2M), and machine type communication (MTC) are implemented by techniques such as beamforming, MIMO, and array antenna, which are 5G communication technologies. . The application of the cloud radio access network (cloud RAN) as the big data processing technology described above can be said to be an example of convergence of 3eG technology and IoT technology.

As various services can be provided according to the above and the development of wireless communication systems, a method for smoothly providing these services is required.

The disclosed embodiments may provide a method and apparatus for transmitting and receiving control information for effectively providing a service in a wireless communication system.

According to some embodiments, a method for setting downlink control information of a base station in a wireless communication system, comprising: transmitting bandwidth portion setting information to a terminal; determining the size of downlink control information (DCI) based on the bandwidth portion setting information; and transmitting a DCI corresponding to the determined size to the terminal.

According to some embodiments, a method for setting downlink control information of a terminal in a wireless communication system, comprising: receiving bandwidth portion setting information from a base station; determining the size of downlink control information (DCI) through the bandwidth portion setting information; detecting a DCI corresponding to the determined size; and transmitting/receiving data based on the detected DCI.

According to the disclosed embodiment, a service can be effectively provided in a wireless communication system.

1 is a diagram illustrating a basic structure in the time-frequency domain of an LTE or similar system according to some embodiments.
2 is a diagram illustrating PDCCH and EPDCCH, which are downlink control channels of LTE or a system similar thereto, according to some embodiments.
3 is a diagram illustrating a downlink control channel in a 5G or similar system according to some embodiments.
4 is a diagram illustrating a method of allocating a resource region for a downlink control channel in a 5G or similar system according to some embodiments.
5 is a diagram for explaining a plurality of subcarrier intervals considered in a 5G or similar system according to some embodiments.
6 is a diagram for explaining settings for a bandwidth part considered in 5G or similar systems according to some embodiments.
7 is a flowchart of a method for configuring downlink control information by a base station according to some embodiments.
8 is a flowchart of a method for a terminal to configure downlink control information according to some embodiments.
9 is a block diagram illustrating the internal structure of a base station according to some embodiments.
10 is a block diagram illustrating an internal structure of a terminal according to some embodiments.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In describing the embodiments in this specification, descriptions of technical contents that are well known in the technical field to which the present invention pertains and are not directly related to the present invention will be omitted. This is to more clearly convey the gist of the present invention without obscuring it by omitting unnecessary description.

For the same reason, in the accompanying drawings, some components are exaggerated, omitted, or schematically illustrated. Also, the size of each component does not entirely reflect the actual size. In each figure, the same reference number is assigned to the same or corresponding component.

Advantages and features of the present invention, and methods of achieving them, will become clear with reference to the detailed description of the following embodiments taken in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and only these embodiments make the disclosure of the present invention complete, and common knowledge in the art to which the present invention belongs. It is provided to completely inform the person who has the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numbers designate like elements throughout the specification. In addition, in describing the present invention, if it is determined that a detailed description of a related function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted. In addition, terms to be described later are terms defined in consideration of functions in the present invention, which may vary according to the intention or custom of a user or operator. Therefore, the definition should be made based on the contents throughout this specification.

Hereinafter, a base station is a subject that performs resource allocation of a terminal, and may be at least one of a gNode B, an eNode B, a Node B, a base station (BS), a wireless access unit, a base station controller, or a node on a network. The terminal may include a user equipment (UE), a mobile station (MS), a cellular phone, a smart phone, a computer, or a multimedia system capable of performing communication functions. In the present invention, downlink (DL) is a radio transmission path of a signal transmitted from a base station to a terminal, and uplink (UL) refers to a radio transmission path of a signal transmitted from a terminal to a base station. In addition, although an LTE or LTE-A system may be described below as an example, embodiments of the present invention may be applied to other communication systems having a similar technical background or channel type. For example, the 5th generation mobile communication technology (5G, new radio, NR) developed after LTE-A may be included in this, and the following 5G may be a concept including existing LTE, LTE-A and other similar services there is. In addition, the present disclosure can be applied to other communication systems through some modifications within a range that does not significantly deviate from the scope of the present invention as determined by those skilled in the art.

At this time, it will be understood that each block of the process flow chart diagrams and combinations of the flow chart diagrams can be performed by computer program instructions. These computer program instructions may be embodied in a processor of a general purpose computer, special purpose computer, or other programmable data processing equipment, so that the instructions executed by the processor of the computer or other programmable data processing equipment are described in the flowchart block(s). It creates means to perform functions. These computer program instructions may also be stored in a computer usable or computer readable memory that can be directed to a computer or other programmable data processing equipment to implement functionality in a particular way, such that the computer usable or computer readable memory The instructions stored in are also capable of producing an article of manufacture containing instruction means that perform the functions described in the flowchart block(s). The computer program instructions can also be loaded on a computer or other programmable data processing equipment, so that a series of operational steps are performed on the computer or other programmable data processing equipment to create a computer-executed process to generate computer or other programmable data processing equipment. Instructions for performing processing equipment may also provide steps for performing the functions described in the flowchart block(s).

Additionally, each block may represent a module, segment, or portion of code that includes one or more executable instructions for executing specified logical function(s). It should also be noted that in some alternative implementations it is possible for the functions mentioned in the blocks to occur out of order. For example, two blocks shown in succession may in fact be executed substantially concurrently, or the blocks may sometimes be executed in reverse order depending on their function.

At this time, the term '~unit' used in this embodiment means software or hardware components such as FPGA (Field Programmable Gate Array) or ASIC (Application Specific Integrated Circuit), and '~unit' refers to certain roles. carry out However, '~ part' is not limited to software or hardware. '~bu' may be configured to be in an addressable storage medium and may be configured to reproduce one or more processors. Therefore, as an example, '~unit' refers to components such as software components, object-oriented software components, class components, and task components, processes, functions, properties, and procedures. , subroutines, segments of program code, drivers, firmware, microcode, circuitry, data, databases, data structures, tables, arrays, and variables. Functions provided within components and '~units' may be combined into smaller numbers of components and '~units' or further separated into additional components and '~units'. In addition, components and '~units' may be implemented to play one or more CPUs in a device or a secure multimedia card.

The wireless communication system has moved away from providing voice-oriented services in the early days and, for example, 3GPP's HSPA (High Speed Packet Access), LTE (Long Term Evolution or E-UTRA (Evolved Universal Terrestrial Radio Access)), LTE-Advanced (LTE-A), LTE-Pro, 3GPP2's High Rate Packet Data (HRPD), UMB (Ultra Mobile Broadband), and IEEE's 802.16e, a broadband wireless network that provides high-speed, high-quality packet data services. evolving into a communication system.

As a representative example of a broadband wireless communication system, in an LTE system, an Orthogonal Frequency Division Multiplexing (OFDM) method is adopted in downlink (DL), and SC-FDMA (Single Carrier Frequency Division Multiplexing Access) in uplink (UL) ) method is used. Uplink refers to a radio link in which a terminal (UE (User Equipment) or MS (Mobile Station)) transmits data or control signals to a base station (eNode B or base station (BS)), and downlink refers to a radio link in which a base station transmits data or a control signal to a terminal. A radio link that transmits data or control signals. The multiple access scheme as described above usually allocates and operates time-frequency resources to carry data or control information (control signals) for each user so that they do not overlap each other, that is, so that orthogonality is established, so that each user's data or Classify control information.

As a future communication system after LTE, that is, a 5G communication system, since it should be able to freely reflect various requirements such as users and service providers, a service that satisfies various requirements at the same time must be supported. Services considered for the 5G communication system include enhanced mobile broadband (eMBB), massive machine type communication (mMTC), ultra reliability low latency communication (URLLC), etc. there is Of course, it is not limited to the above example, and more various types of services may exist.

eMBB may aim to provide a data transmission rate that is more improved than that supported by existing LTE, LTE-A or LTE-Pro. For example, in a 5G communication system, an eMBB must be able to provide a peak data rate of 20 Gbps in downlink and a peak data rate of 10 Gbps in uplink from the perspective of one base station. In addition, the 5G communication system should provide a maximum transmission rate and, at the same time, an increased user perceived data rate of the terminal. In order to satisfy these requirements, various transmission/reception technologies are required to be improved, including a more advanced Multi Input Multi Output (MIMO) transmission technology. In addition, while signals are transmitted using a maximum 20MHz transmission bandwidth in the 2GHz band currently used by LTE, the 5G communication system uses a frequency bandwidth wider than 20MHz in a frequency band of 3 to 6GHz or 6GHz or higher to meet the requirements of the 5G communication system. data transfer rate can be satisfied. Of course, the frequency band and frequency bandwidth are not limited to the above examples. At the same time, mMTC is being considered to support application services such as Internet of Things (IoT) in 5G communication systems. In order to efficiently provide the Internet of Things, mMTC may require support for large-scale terminal access within a cell, improved terminal coverage, improved battery time, and reduced terminal cost. The IoT is attached to various sensors and various devices. Since it provides a communication function, it should be able to support a large number of terminals (eg, 1,000,000 terminals/km2) within a cell. In addition, since a terminal supporting mMTC is likely to be located in a shadow area that is not covered by a cell, such as the basement of a building due to the nature of the service, it may require a wider coverage than other services provided by the 5G communication system. A terminal supporting mMTC must be composed of a low-cost terminal, and since it is difficult to frequently replace a battery of the terminal, a very long battery life time such as 10 to 15 years may be required.

Finally, in the case of URLLC, it may be a cellular-based wireless communication service used for a specific purpose (mission-critical). For example, remote control of robots or machinery, industrial automation, unmaned aerial vehicles, remote health care, emergency situations A service used for emergency alert or the like may be considered. Therefore, communications provided by URLLC may need to provide very low latency and very high reliability. For example, a service supporting URLLC needs to satisfy an air interface latency of less than 0.5 milliseconds, and at the same time has a requirement of a packet error rate of 10-5 or less. Therefore, for a service that supports URLLC, a 5G system must provide a smaller transmit time interval (TTI) than other services, and at the same time, a design that allocates wide resources in the frequency band to secure the reliability of the communication link. items may be requested.

The three services of 5G, namely eMBB, URLLC, and mMTC, can be multiplexed and transmitted in one system. At this time, different transmission/reception techniques and transmission/reception parameters may be used between services in order to satisfy different requirements of each service.

According to some embodiments, the 5G wireless communication system seeks to support both services requiring high transmission rates as well as services having very short transmission delays and services requiring high connection density, unlike conventional services. In these scenarios, one system should be able to provide various services with different transmission/reception techniques and transmission/reception parameters in order to satisfy the various requirements and services of users. It is important to design it so that no system-limited constraints arise. Therefore, in 5G, it is designed to support multiple numerologies, that is, subcarrier spacing, and accordingly, in 5G, unlike conventional LTE, time and frequency resources must be used more flexibly.

In order to achieve high-speed data service up to several Gbps in the 5G system, transmission and reception of ultra-wide bandwidth signals of tens to hundreds of MHz or several GHz are being considered. At this time, the size of the bandwidth supportable by the terminal may not be the same as the size of the system bandwidth, and accordingly, the base station may support signal transmission and reception by setting a specific bandwidth part to the corresponding terminal. Alternatively, according to the relationship in which power consumption increases in proportion to the transmission and reception bandwidth, bandwidth portions of different sizes can be set and operated for the terminal for the purpose of efficiently managing power consumption of the terminal or base station through transmission and reception bandwidth adjustment. . Alternatively, in order to support subcarrier sizes of different sizes, one or a plurality of bandwidth parts may be set for a corresponding terminal, and subcarrier intervals of each bandwidth part may be set to different sizes for operation. In addition to this, for various purposes, the base station may set a bandwidth portion to the terminal, and may transmit/receive signals using the corresponding bandwidth portion. At this time, the bandwidth part may be set to various system parameter values.

When scheduling data to be transmitted to the UE or data to be transmitted by the UE, the base station can determine which bandwidth portion to transmit, and can transmit different downlink control information according to configuration information of the corresponding bandwidth portion. More specifically, the base station can set one or a plurality of bandwidth parts to the terminal for one carrier or one serving cell, and can transmit and receive signals using one or a plurality of bandwidth parts among the set bandwidth parts. there is. At this time, scheduling information for data transmitted in each bandwidth part may be different according to various system parameters set for each bandwidth part, such as bandwidth size, slot duration, subcarrier interval, etc. Accordingly, the base station can transmit one or a plurality of different downlink control information.

The present invention proposes a method for transmitting downlink control information for efficient system operation in various signal transmission/reception operations using a bandwidth part. The base station may transmit downlink control information for data transmission in the same bandwidth part as the bandwidth part in which the downlink control information is transmitted to the terminal. Alternatively, the base station may transmit downlink control information for data transmission to the terminal in a bandwidth part different from the bandwidth part in which the downlink control information is transmitted. Similarly, the base station may transmit downlink control information (UL grant) for the terminal to transmit data in the same bandwidth portion as the bandwidth portion in which the downlink control information is transmitted. Alternatively, the base station may transmit downlink control information (UL grant) for allowing the terminal to transmit data in a bandwidth portion different from that in which the downlink control information is transmitted. At this time, the base station may transmit downlink control information for data transmission and reception using a plurality of bandwidth parts with the terminal. In order to support the operation described above, an additional downlink control information field is required, or different sizes of downlink control information fields are required, or different interpretations of the same downlink control information field are required. (Interpretation) may be requested. The present invention provides a method and apparatus for setting a downlink control information field in consideration of this.

Hereinafter, the frame structure of the LTE and LTE-A systems will be described in more detail with reference to the drawings.

1 is a diagram illustrating a basic structure in the time-frequency domain of an LTE or similar system according to some embodiments.

Referring to FIG. 1, in a radio resource domain, a horizontal axis represents a time domain and a vertical axis represents a frequency domain. The minimum transmission unit in the time domain may be an OFDM symbol, and N _symb (101) OFDM symbols may be gathered to form one slot (102), and two slots may be gathered to form one subframe (103). can do. At this time, the length of the slot 102 may be 0.5 ms, and the length of the subframe 103 may be 1.0 ms. Also, the radio frame 104 may be a time domain unit consisting of 10 subframes. The minimum transmission unit in the frequency domain may be a subcarrier, and the bandwidth of the entire system transmission bandwidth may consist of a total of N _sc ^BW (105) subcarriers. A basic unit of resources in the time-frequency domain may be a resource element (106, Resource Element, RE) and may be represented by an OFDM symbol index and a subcarrier index. A resource block (107, Resource Block, RB or Physical Resource Block, PRB) is defined as N _symb (101) contiguous OFDM symbols in the time domain and N _sc ^RB (108) contiguous subcarriers in the frequency domain. Accordingly, one RB 108 may be composed of N _symb x N _RB REs 106 . In general, the minimum transmission unit of data may be an RB unit. In an LTE system, N _symb = 7 and N _RB =12, and N _BW and N _RB may be proportional to the bandwidth of the system transmission band. However, these specific values may be applied variably depending on the system.

Next, downlink control information (DCI) in LTE and LTE-A systems will be described in detail.

According to some embodiments, scheduling information for downlink data or uplink data in an LTE system may be transmitted from a base station to a terminal through DCI. According to some embodiments, DCI can define various formats, whether it is scheduling information for uplink data or scheduling information for downlink data, whether it is a compact DCI having a small size of control information, using multiple antennas. Depending on whether spatial multiplexing is applied or whether DCI is used for power control, a predetermined DCI format may be applied and operated. For example, DCI format 1, which is scheduling control information for downlink data, is configured to include at least the following control information.

- Resource allocation type 0/1 flag: Notifies whether the resource allocation method is type 0 or type 1. Type 0 allocates resources in RBG (Resource Block Group) units by applying a bitmap method. In the LTE system, a basic unit of scheduling is a resource block (RB) represented by time and frequency domain resources, and an RBG is composed of a plurality of RBs to become a basic unit of scheduling in the type 0 scheme. Type 1 allows a specific RB to be allocated within an RBG.

- Resource block assignment: RBs allocated for data transmission are notified. The resource to be expressed is determined according to the system bandwidth and resource allocation method.

- Modulation and coding scheme (MCS): Notifies the modulation scheme used for data transmission and the size of the transport block, which is the data to be transmitted.

- HARQ process number: Notifies the HARQ process number.

- New data indicator: Notifies whether it is HARQ initial transmission or retransmission.

- Redundancy version: Notifies the redundancy version of HARQ.

- Transmit Power Control (TPC) command for Physical Uplink Control CHannel (PUCCH): Notifies a transmit power control command for PUCCH, which is an uplink control channel.

According to some embodiments, the DCI may be transmitted through a physical downlink control channel (PDCCH) or an enhanced PDCCH (EPDCCH) that is a downlink physical control channel through channel coding and modulation processes.

According to some embodiments, a Cyclic Redundancy Check (CRC) may be attached to the payload of the DCI message, and the CRC may be scrambled with a Radio Network Temporary Identifier (RNTI) corresponding to the identity of the UE. Different RNTIs may be used according to the purpose of the DCI message, eg, UE-specific data transmission, power control command, or random access response. Soon, the RNTI is not transmitted explicitly but is included in the CRC calculation process and transmitted. Upon receiving the DCI message transmitted on the PDCCH, the terminal checks the CRC using the allocated RNTI, and if the CRC check result is correct, it can be known that the corresponding message has been transmitted to the terminal.

Next, a resource allocation (RA) method for PDSCH (Physical Downlink Shared Channel) of LTE, LTE-A or similar systems will be described in detail.

According to some embodiments, LTE may support resource allocation schemes for three types of PDSCH (resource allocation type 0, resource allocation type 1, and resource allocation type 2).

가 될 수 있다. RBG당 RB 수, 즉 P 값이 작을수록 스케쥴링의 유연성이 커지게 되는 장점이 있고 반면에 제어 시그널링 오버헤드가 증가하는 단점이 있다. 따라서 P 값은 충분한 자원할당의 유연성을 유지하면서도 요구되는 비트 수를 줄일 수 있도록 적절히 선택되어야 한다. LTE에서는 RBG 크기는 하향링크 셀 대역폭에 의해 결정되고 이 때 가능한 RBG 크기는 하기의 표 1과 같다.In resource allocation type 0, non-contiguous RB allocation is supported on the frequency axis, and allocated RBs are indicated using a bitmap. In this case, when corresponding RBs are indicated with a bitmap having the same size as the number of RBs, high control signaling overhead may be caused because a very large bitmap must be transmitted for a large cell bandwidth. Therefore, in the resource allocation type 0, a method of reducing the size of the bitmap is used by grouping consecutive RBs into groups and indicating the group instead of directly indicating each RB in the frequency domain. For example, when the total transmission bandwidth is N _RBs and the number of RBs per Resource Block Group (RBG) is P, the bitmap required to inform RB allocation information in resource allocation type 0 is

can be The smaller the number of RBs per RBG, that is, the smaller the P value, has the advantage of greater flexibility in scheduling, but has the disadvantage of increasing control signaling overhead. Therefore, the P value must be appropriately selected so as to reduce the number of required bits while maintaining sufficient resource allocation flexibility. In LTE, the RBG size is determined by the downlink cell bandwidth, and the possible RBG sizes at this time are shown in Table 1 below.

In resource allocation type 1, resource allocation is performed by dividing the entire RBG set on the frequency axis into scattered RBG subsets. The number of subsets is given from the cell bandwidth, and the number of subsets of resource allocation type 1 is equal to the group size (RBG size, P) of resource allocation type 0. RB allocation information of resource allocation type 1 may be composed of three fields as follows.

비트)- First field: selected RBG subset indicator (

beat)

- 2nd field: indicator of shift of resource allocation within subset (1 bit)

비트)- Third field: Bitmap for assigned RBG (

beat)

으로 자원할당 타입 0에서 요구되는 비트 수와 동일하게 된다. 따라서 단말에게 자원할당 타입이 0인지 1인지 알려주기 위해, 1 비트의 지시자가 추가로 붙게 된다.As a result, the total number of bits used in resource allocation type 1 is

is equal to the number of bits required for resource allocation type 0. Accordingly, a 1-bit indicator is additionally attached to inform the UE whether the resource allocation type is 0 or 1.

Unlike the two resource allocation types described above, resource allocation type 2 does not depend on a bitmap. Instead, resource allocation is indicated by the starting point and length of the RB allocation. Accordingly, resource allocation types 0 and 1 both support non-contiguous RB allocation, whereas resource allocation type 2 supports only contiguous allocation. As a result, RB allocation information of resource allocation type 2 is composed of two fields as follows.

-First field: indicator indicating the RB start point (RB _start )

-Second field: indicator indicating the length of contiguously allocated RBs (L _CRBs )

의 비트수가 사용된다. In resource allocation type 2, the total

number of bits is used.

All three types of resource allocation correspond to VRB (Virtual Resource Block). For resource allocation types 0 and 1, the VRB is directly mapped to the Physical Resource Block (PRB) in a localized form. On the other hand, resource allocation type 2 supports both localized and distributed VRB. Therefore, in resource allocation type 2, an indicator for determining localized and distributed VRB is added.

2 is a diagram illustrating PDCCH and EPDCCH, which are downlink control channels of LTE or a system similar thereto, according to some embodiments.

Referring to FIG. 2, PDCCH 201 is time multiplexed with PDSCH 203, which is a data transmission channel, and transmitted over the entire system bandwidth. The area of the PDCCH 201 is represented by the number of OFDM symbols, which may be indicated to the terminal by a Control Format Indicator (CFI) transmitted through a Physical Control Format Indicator Channel (PCFICH). By allocating the PDCCH 201 to the OFDM symbol coming at the beginning of the subframe, the UE can decode the downlink scheduling assignment as quickly as possible, thereby reducing the decoding delay for the Downlink Shared Channel (DL-SCH), that is, the overall downlink There is an advantage of reducing link transmission delay. According to some embodiments, one PDCCH can carry one DCI message, and since a plurality of terminals can be simultaneously scheduled for downlink and uplink, a plurality of PDCCHs can be simultaneously transmitted in each cell. . A cell-specific reference signal (CRS) 204 is used as a reference signal for decoding the PDCCH 201. The CRS 204 is transmitted every subframe over all bands, and scrambling and resource mapping may vary according to cell ID (Identity). Since the CRS 204 is a reference signal commonly used by all terminals, terminal-specific beamforming cannot be used. Therefore, the multi-antenna transmission method for the PDCCH of LTE can be limited to open-loop transmission diversity. The number of ports of the CRS may be implicitly known to the terminal from decoding of a physical broadcast channel (PBCH).

According to some embodiments, resource allocation of the PDCCH 201 may be based on Control-Channel Elements (CCEs), and one CCE may include 9 Resource Element Groups (REGs), for a total of 36 Resource Element Groups (REs). elements). The number of CCEs required for a specific PDCCH 201 may be 1, 2, 4, or 8, which may vary depending on the channel coding rate of the DCI message payload. This is also not limited to the above examples. Different numbers of CCEs may be used to implement link adaptation of the PDCCH 201. The terminal needs to detect a signal without knowing information about the PDCCH 201. In LTE, a search space representing a set of CCEs is defined for blind decoding. The search space is composed of a plurality of sets in the aggregation level (AL) of each CCE, which is not explicitly signaled and can be implicitly defined through a function and subframe number according to the UE identity. Within each subframe, the UE decodes the PDCCH 201 for all possible resource candidates that can be created from CCEs within the configured search space, and information declared valid for the corresponding UE through CRC check. can handle

According to some embodiments, the search space may be classified into a terminal-specific search space and a common search space. A certain group of terminals or all terminals can search the common search space of the PDCCH 201 in order to receive cell-common control information such as dynamic scheduling for system information or paging messages. For example, scheduling allocation information of a DL-SCH for transmission of System Information Block (SIB)-1 including cell operator information may be received by examining the common search space of the PDCCH 201.

According to FIG. 2, the EPDCCH 202 may be frequency multiplexed with the PDSCH 203 and transmitted. The base station can appropriately allocate resources of the EPDCCH 202 and the PDSCH 203 through scheduling, and thereby effectively support coexistence with data transmission for the existing LTE terminal. However, since the EPDCCH 202 is allocated and transmitted in one entire subframe on the time axis, there is a problem in that there is a loss in terms of transmission delay time. A plurality of EPDCCHs 202 constitute one EPDCCH 202 set, and the EPDCCH 202 set is allocated in units of Physical Resource Block (PRB) pairs. Location information for the EPDCCH 202 set is set UE-specifically and is signaled through Remote Radio Control (RRC). Up to two EPDCCH 202 sets can be set for each terminal, and one EPDCCH 202 set can be simultaneously multiplexed and set to different terminals.

According to some embodiments, resource allocation of the EPDCCH 202 may be based on Enhanced CCE (ECCE), and one ECCE may consist of 4 or 8 Enhanced REGs (EREGs), and the number of EREGs per ECCE may vary according to the CP length and subframe configuration information. One EREG may consist of 9 REs, and 16 EREGs may exist per PRB pair. The EPDCCH transmission method may be classified into localized/distributed transmission according to the RE mapping method of EREG. The aggregation level of ECCE can be 1, 2, 4, 8, 16, or 32, which is determined by the CP length, subframe configuration, EPDCCH format, and transmission method.

According to some embodiments, EPDCCH 202 only supports UE-specific search spaces. Therefore, a UE that wants to receive a system message must search for a common search space on the existing PDCCH 201.

According to some embodiments, in the EPDCCH 202, a Demodulation Reference Signal (DMRS) 205 is used as a reference signal for decoding. Therefore, precoding for the EPDCCH 202 can be set by the base station, and UE-specific beamforming can be used. Through the DMRS 205, UEs can perform decoding on the EPDCCH 202 without knowing which precoding is used. In the EPDCCH 202, the same pattern as the DMRS of the PDSCH 203 may be used. However, unlike the PDSCH 203, the DMRS 205 on the EPDCCH 202 can support transmission using up to four antenna ports. The DMRS 205 is transmitted only in the corresponding PRB through which the EPDCCH is transmitted.

According to some embodiments, the port configuration information of the DMRS 205 varies according to the EPDCCH 202 transmission method. In the case of a localized transmission scheme, an antenna port corresponding to ECCE to which the EPDCCH 202 is mapped may be selected based on the ID of the terminal. When different terminals share the same ECCE, that is, when multiuser MIMO transmission is used, a DMRS antenna port may be allocated to each terminal. Alternatively, the DMRS 205 may be shared and transmitted. In this case, it may be divided into a DMRS 205 scrambling sequence configured by higher layer signaling. In the case of a distributed transmission method, up to two antenna ports of the DMRS 205 are supported, and a diversity technique of a precoder cycling method is supported. DMRS 205 may be shared for all REs transmitted within one PRB pair.

According to some embodiments, in LTE, an entire PDCCH region consists of a set of CCEs in a logical region, and a search space consisting of a set of CCEs exists. The search space is divided into a common search space and a UE-specific search space, and the search space for the LTE PDCCH may be defined as follows.

According to the definition of the search space for the PDCCH described above, the UE-specific search space may be implicitly defined through a function and a subframe number based on UE identity without being explicitly signaled. In other words, since the terminal-specific search space can change according to the subframe number, this means that it can change over time, and through this, the problem that a specific terminal cannot use the search space by other terminals among terminals ( It is defined as a blocking problem.) can be solved. If a UE cannot be scheduled in a corresponding subframe because all CCEs it examines are already being used by other UEs scheduled in the same subframe, since this search space changes over time, in the next subframe Such a problem may not occur. For example, even if parts of the UE-specific search spaces of UE #1 and UE #2 overlap in a specific subframe, since the UE-specific search spaces change for each subframe, the overlap in the next subframe is different from this. can be expected to

According to some embodiments, according to the definition of the search space for the PDCCH described above, in the case of a common search space, a predetermined group of terminals or all terminals must receive the PDCCH, so it is defined as a set of pre-promised CCEs. In other words, the common search space may not change according to the identity of the terminal or the subframe number. Although a common search space exists for transmission of various system messages, it can also be used to transmit control information of individual terminals. Through this, the common search space can also be used as a solution to a phenomenon in which a terminal is not scheduled due to insufficient resources available in the terminal-specific search space.

According to some embodiments, the search space is a set of candidate control channels consisting of CCEs that the UE should attempt to decode on a given aggregation level, and various aggregation levels that make one bundle with 1, 2, 4, and 8 CCEs. Because of this, the terminal can have a plurality of search spaces. The number of PDCCH candidates to be monitored by the UE within the search space defined according to the aggregation level in the LTE PDCCH is defined in the following table.

According to [Table 2], in the case of a UE-specific search space, aggregation levels {1, 2, 4, 8} can be supported, and in this case, {6, 6, 2, 2} PDCCH candidate groups can be provided. In the case of the common search space 302, aggregation levels {4, 8} may be supported, and at this time, {4, 2} PDCCH candidate groups may be respectively provided. The reason why the common search space supports only {4, 8} aggregation level is to improve coverage characteristics because system messages generally have to reach cell edges.

According to some embodiments, DCI transmitted in a common search space is defined only for a specific DCI format such as 0/1A/3/3A/1C corresponding to a purpose such as system message or power control for a terminal group. It can be. A DCI format with spatial multiplexing may not be supported within a common search space. Of course, it is not limited to the above examples. The downlink DCI format to be decoded in the UE-specific search space may vary depending on the transmission mode set for the corresponding UE. Since the setting of the transmission mode is performed through RRC signaling, an exact subframe number for whether the corresponding setting is effective for the corresponding terminal is not specified. Therefore, the terminal can be operated not to lose communication by always performing decoding for DCI format 1A regardless of the transmission mode.

In the above, the downlink control channel transmission method and search space in LTE and LTE-A have been described, and below, the downlink control channel in a 5G communication system or a similar system will be described in more detail with reference to the drawings.

3 is a diagram illustrating a downlink control channel in a 5G or similar system according to some embodiments.

3 illustrates an example of a basic unit of time and frequency resources constituting a downlink control channel that can be used in 5G. Referring to FIG. 3, a basic unit of time and frequency resources constituting a control channel (REG, or NR (New Radio)-REG may be named. Hereinafter, in the present invention, it is named NR-REG 303 ) may consist of 1 OFDM symbol 301 in the time axis and may consist of 12 subcarriers 302, that is, 1 RB, in the frequency axis. In constituting the basic unit of the control channel, by assuming that the time axis basic unit is 1 OFDM symbol 301, the data channel and the control channel can be time-multiplexed within one subframe. By locating the control channel before the data channel, the user's processing time can be reduced, making it easy to satisfy the latency requirement. By setting the basic unit of the frequency axis of the control channel to 1 RB 302, frequency multiplexing between the control channel and the data channel can be performed more efficiently. Of course, it is not limited to the above examples.

By concatenating the NR-REGs 303 shown in FIG. 3, control channel regions of various sizes can be set. For example, when a basic unit to which a downlink control channel is allocated in 5G is an NR-CCE 304, 1 NR-CCE 304 may include a plurality of NR-REGs 303. Describing the NR-REG 303 shown in FIG. 3 as an example, the NR-REG 303 may consist of 12 REs, and 1 NR-CCE 304 is divided into 4 NR-REGs 303. If configured, it means that 1 NR-CCE 304 can be configured with 48 REs. When a downlink control area is set, the corresponding area can be composed of a plurality of NR-CCEs (304), and a specific downlink control channel is one or more NR-CCEs (304) according to the aggregation level (AL) in the control area. It can be mapped to and transmitted. NR-CCEs 304 in the control area are classified by number, and at this time, the number can be assigned according to a logical mapping method.

The basic unit of the downlink control channel shown in FIG. 3, that is, the NR-REG 303, may include both REs to which DCI is mapped and a region to which the DMRS 305, which is a reference signal for decoding them, is mapped. At this time, the DMRS 305 can be efficiently transmitted considering overhead according to RS allocation. For example, when a downlink control channel is transmitted using a plurality of OFDM symbols, the DMRS 305 may be transmitted only in the first OFDM symbol. The DMRS 305 may be mapped and transmitted considering the number of antenna ports used to transmit the downlink control channel. The diagram shown in FIG. 3 shows an example in which two antenna ports are used. At this time, a DMRS 306 transmitted for antenna port #0 and a DMRS 307 transmitted for antenna port #1 may exist. DMRS for different antenna ports can be multiplexed in various ways. 3 shows an example in which DMRSs corresponding to different antenna ports are orthogonally transmitted in different REs. In this way, the DMRS may be transmitted after being subjected to frequency division multiplexing (FDM) or may be transmitted after being subjected to code division multiplexing (CDM). Of course, it is not limited to the above example, and other types of DMRS patterns may exist, which may be related to the number of antenna ports. Hereinafter, in describing the present invention, it is assumed that two antenna ports are used. The principle of the present invention can be equally applied to the number of two or more antenna ports.

4 is a diagram illustrating a method of allocating a resource region for a downlink control channel in a 5G or similar system according to some embodiments.

In FIG. 4, the system bandwidth 410 on the frequency axis and 1 slot 420 on the time axis (in the example of FIG. 4, it is assumed that 1 slot is 7 OFDM symbols, but it is also applicable when 1 slot is 14 OFDM symbols.) are showing In FIG. 4, the total system bandwidth 410 includes a plurality of bandwidth parts (for example, in FIG. 4, bandwidth part # 1 402, bandwidth part # 2 403, bandwidth part # 3 404, bandwidth part # 4 405 ) of the four bandwidth parts). 4 shows an example in which two control areas (control area #1 440 and control area #2 450) are set. The control regions 440 and 450 may be set to specific subbands within the entire system bandwidth 410 on the frequency axis. Referring to FIG. 4, control area #1 (440) is set in bandwidth part #1 (402), and control area #2 (450) is set in bandwidth part #4 (405). The time axis can be set to one or a plurality of OFDM symbols, and this can be defined as a control region length (Control Resource Set Duration, 460, 470). In the example of FIG. 4, control region #1 (440) is set to control region length #1 (460) of 2 symbols, and control region #2 (450) is set to control region length #2 (470) of 1 symbol. It is set.

In New Radio (NR) to 5G systems, a plurality of control regions may be set within one system, one carrier, one cell, or one bandwidth part from the point of view of a base station. In addition, a plurality of control regions may be set within one carrier, one cell, or one bandwidth part from the terminal point of view. At this time, only some of the control areas among the set control areas in the system may be set for the terminal. Accordingly, the terminal may not know whether a specific control area exists in the system. As a specific example, in FIG. 4, two control areas of control area #1 (440) and control area #2 (450) are set in the system, and control area #1 (440) is set for terminal #1. and control area #1 440 and control area #2 450 may be set for terminal #2. At this time, if there is no additional indicator, terminal #1 may not know whether control region #2 450 exists.

The control region in 5G described above may be set as a common control region, UE-group common, or UE-specific. The control region may be configured for each UE through UE-specific signaling, UE group common signaling, or RRC signaling. Setting the control region to the terminal means providing information such as the location of the control region, a bandwidth portion, a subband, resource allocation of the control region, the length of the control region, and the like. For example, the control area setting information may include at least the information in Table 3 below.

Of course, it is not limited to the above example, and various pieces of information necessary for transmitting a downlink control channel may be set in the terminal in addition to the above configuration information.

In the 5G system, it is necessary to flexibly define and operate the frame structure considering various services and requirements. For example, it may be considered that each service has a different subcarrier interval according to requirements. Currently, two methods are being considered to support a plurality of subcarriers in a 5G communication system. As a first method for supporting a plurality of subcarriers in the 5G communication system, a set of subcarrier intervals that the 5G communication system may have may be determined using Equation 1 below.

Here, f ₀ represents the basic subcarrier spacing of the system, and m represents an integer scaling factor. For example, if f ₀ is 15 kHz, the set of subcarrier spacing that the 5G communication system can have is 7.5 KHz. , 15KHz, 30KHz, 60KHz, 120KHz and the like. As in Equation 1, a system may be configured using all or part of the corresponding set. In the present invention, according to the two methods described above, it is assumed that a 15KHz, 30KHz, 60KHz subcarrier interval set in which f ₀ is 15kHz is used in a 5G communication system, and the present invention is described. However, the technique proposed in the present invention can be applied without limitation to other subcarrier spacing sets (eg, f ₀ of 17.5 KHz and subcarrier spacing sets of 17.5 KHz, 35 KHz, and 70 KHz). If subcarrier spacing sets of 17.5 KHz, 35 KHz, and 70 KHz are considered in the present invention, f ₀ may be mapped to the described technology based on 15 kHz. Similarly, 35 kHz, 70 kHz, and 140 kHz are mapped one-to-one with 30 kHz, 60 KHz, and 120 kHz, respectively, so that the present invention can be described.

5 is a diagram for explaining a plurality of subcarrier intervals considered in a 5G or similar system according to some embodiments.

5 illustrates a resource element 500 when the subcarrier intervals are Δf ₁ (501), Δf ₂ (502), and Δf ₃ (503), respectively. In the example of FIG. 5 , the values of the subcarrier intervals of each resource element, that is, Δf ₁ (501), Δf ₂ (502), and Δf ₃ (503) correspond to 15 kHz, 30 kHz, and 60 kHz, respectively. In addition, each resource element has an OFDM symbol length of T _s (504), T _s ' (505), and T _s '' (506). As a feature of the OFDM symbol, since the subcarrier spacing and the length of the OFDM symbol have a reciprocal relationship with each other, it can be seen that the larger the subcarrier spacing, the shorter the symbol length. Therefore, T _s (504) is 2 times T _s ' (505) and 4 times T _s ”” (506).

Next, the setting of the bandwidth part in the currently discussed 5G communication system will be described in detail. Here, the bandwidth part may be defined as a bandwidth equal to or smaller than the entire bandwidth.

6 is a diagram for explaining settings for a bandwidth part considered in 5G or similar systems according to some embodiments.

6 shows an example of setting a bandwidth portion considered in a 5G communication system. The base station may set one or a plurality of bandwidth parts to the terminal. 6 shows an example in which the bandwidth 601 of the terminal is set to two bandwidth parts, that is, a bandwidth part #1 610 and a bandwidth part #2 611.

The base station may set the position and bandwidth size of each bandwidth part to the terminal. For example, in FIG. 6, bandwidth part #1 610 is located at center frequency #1 604 and may have a bandwidth size corresponding to bandwidth #1 602, and bandwidth part #2 611 is center frequency It may be located in #2 (605) and set to have a bandwidth size corresponding to bandwidth #2 (603). Of course, it is not limited to the above example, and the position of each bandwidth part may be set in various ways. For example, it may be set by notifying an offset value (PRB or subcarrier spacing unit) based on a specific reference point within the bandwidth of the terminal or within the system bandwidth. Of course, it is not limited to the above example, and the size of each bandwidth part may be set in various ways. For example, it may be set by notifying the number of RBs or RBGs (RB groups) existing in each bandwidth part.

According to some embodiments, the base station may set the numerology of each bandwidth part to the terminal, for example, a subcarrier space. For example, in FIG. 6, bandwidth part #1 610 can be set to Δf ₁ (=15kHz, 608) as a subcarrier interval, and bandwidth part #2 611 can be set to Δf ₂ (=30kHz, 609) as a subcarrier interval. can be set. Also, the slot duration of each bandwidth part may vary according to the subcarrier interval. In this case, the slot length may vary not only by the subcarrier interval but also by the number of OFDM symbols constituting the slot. The base station may set information on the slot length of each bandwidth portion, that is, information on the number of OFDM symbols corresponding to one slot (eg, 7 OFDM symbols or 14 OFDM symbols) to the terminal. In FIG. 6, bandwidth part #1 (610) can be set to slot length #1 (X OFDM symbol, 606), and bandwidth part #2 (611) can be set to slot length #2 (Y OFDM symbol, 607). 6, it is assumed that X ≤ Y.

According to some embodiments, the base station may set a control resource set (Control Resource Set) for a downlink control channel for transmitting and receiving DCI (Downlink Control Information) in each bandwidth part to the terminal. For example, in FIG. 6, the base station may set control region #1 612 as a control region for transmitting DCI for bandwidth part #1 610 to the terminal, and DCI for bandwidth part #2 611. Control area #2 613 can be set as a control area for transmitting.

At this time, the terminal can search only the control area of the activated bandwidth part among the set bandwidth part at the time set to search the control area. In other words, the terminal may not perform blind detection for DCI in the control region of the deactivated bandwidth part among the bandwidth parts set at the time set to search the control domain. In addition, the terminal can search for the set control area regardless of whether the set bandwidth part is activated or not. For example, it is possible to search the set control area regardless of whether the bandwidth part is activated or not, but in the present invention, the control area in which cell common or group common control information or system control information is transmitted is transmitted. It is assumed that only the control region of the activated bandwidth part among the set bandwidth parts is searched at the time set to search.

According to some embodiments, the base station may inform the terminal of all or part of the system parameters indicated in [Table 3], for example, when setting the control region in each bandwidth part to the terminal. The base station may transmit configuration information on the bandwidth portion described above to the UE through higher layer signaling, for example, RRC signaling, and may transmit configuration information on the bandwidth portion to the UE through common control information such as System Information Block (SIB). can also be transmitted.

As described above, in order to achieve high-speed data service up to several Gbps in the 5G system, transmission and reception of ultra-wide bandwidth signals of tens to hundreds of MHz or several GHz are being considered. At this time, the size of the bandwidth supportable by the terminal may not be the same as the size of the system bandwidth, and accordingly, signal transmission and reception can be supported by setting a specific bandwidth part to the corresponding terminal.

At this time, when scheduling data to be transmitted to the terminal, the base station may determine which bandwidth portion to transmit, and may transmit different downlink control information (DCI) according to configuration information of the corresponding bandwidth portion. More specifically, the base station may set one or a plurality of bandwidth parts to the terminal, and may transmit a signal using one or a plurality of bandwidth parts among the set bandwidth parts. At this time, the scheduling information for data transmitted in each bandwidth part may be different according to various system parameters set for each bandwidth part, for example, bandwidth size, slot duration, subcarrier interval, etc. Accordingly, one or a plurality of different DCIs may be transmitted.

In this case, downlink control information (DCI) transmitted to instruct or set reception of downlink data through the downlink data channel (PDSCH) or transmission of uplink data through the uplink data channel (PUSCH) and transmission and reception according to DCI Data transmission and reception can be performed in the same or different bandwidth parts. Here, DCI and data transmission/reception are performed in the same bandwidth part, which means that the DCI transmitted in bandwidth part #1 610 transmits downlink data through the downlink data channel (PDSCH) in bandwidth part #1 610. It may mean receiving, or being instructed or configured to transmit uplink data through the uplink data channel (PUSCH) in the bandwidth part # 1 610. On the other hand, DCI and data transmission/reception are performed in different bandwidth parts, meaning that the DCI transmitted in bandwidth part #1 (610) of the terminal is downlink through the downlink data channel (PDSCH) in bandwidth part #2 (611). It may mean receiving data or being instructed or configured to transmit uplink data through the uplink data channel (PUSCH) in the bandwidth part #2 611.

Among the operations described above, in order for at least DCI and data transmission and reception to be performed in different bandwidth parts, an indicator (eg, a bandwidth part indicator or a bandwidth part indicator) indicating the bandwidth part in which data transmission and reception is performed in the DCI is required, The size of the bandwidth portion indicator field may be determined according to the number N of bandwidth portions configured for the terminal. For example, the size of the bandwidth portion indicator field may be determined as ceil (log ₂ N). In this case, when DCI and data transmission/reception are performed in different bandwidth parts, or when the bandwidth part indicator field exists in DCI, the DCI size may be different according to the size of the bandwidth part in which the data transmission/reception is performed. For example, the size of a field indicating frequency resource allocation information of the DCI (Frequency domain resource assignment field) may vary according to the number of RBs or a bandwidth set in a bandwidth portion where data is transmitted and received. The present invention proposes a DCI setting method in consideration of the above points, and provides a method and apparatus for transmitting and receiving DCI.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. At this time, it should be noted that the same components in the accompanying drawings are indicated by the same reference numerals as much as possible. In addition, detailed descriptions of well-known functions and configurations that may obscure the subject matter of the present invention will be omitted.

In addition, in the detailed description of the embodiments of the present invention, LTE, LTE-A or 5G systems will be the main target, but the main point of the present invention is that the present invention can be applied to other communication systems having similar technical backgrounds and channel types. It can be applied with slight modifications within a range that does not significantly deviate from the scope of the present invention, which will be possible with the judgment of those skilled in the art.

<First Embodiment>

The base station may configure one or a plurality of bandwidth parts for the terminal. Each bandwidth portion may be set to different system parameters, such as subcarrier spacing, bandwidth size or number of RBs, RBG size, slot length, and the like.

The base station can transmit an indicator for activating or deactivating one or a plurality of bandwidth parts among one or a plurality of bandwidth parts set to the terminal, and the base station and the terminal can transmit and receive signals using the activated bandwidth part. can In this case, the indicator for activating or deactivating the bandwidth portion may be an indicator for changing the activation bandwidth portion. For example, if only one bandwidth part is activated at a specific time, when a terminal with bandwidth part #1 activated receives an indicator from a base station to activate bandwidth part #2, the terminal transmits bandwidth part #1 It can be determined that it is deactivated and bandwidth part #2 is activated. In other words, the terminal can change the active bandwidth part from bandwidth part #1 to bandwidth part #2 through the indicator. The corresponding indicator may be informed from the base station to the terminal through higher layer signaling (eg, RRC signaling or MAC CE signaling) or L1 signaling (eg, common DCI, group-common DCI, or terminal-specific DCI). At this time, it is also possible to activate or deactivate the bandwidth portion or change the active bandwidth portion using a timer set for each bandwidth portion or a timer set for the terminal. For example, the terminal for which bandwidth part #1 is activated according to the above methods operates a deactivation timer for bandwidth part #1 or a bandwidth part deactivation timer set for the terminal from the time when the bandwidth part #1 is activated. When the timer value reaches the preset deactivation timer value, the terminal may deactivate the activated bandwidth portion #1. At this time, if the terminal receives the DCI for the currently activated bandwidth portion before the timer value reaches the preset inactivation timer value, the terminal may initialize the timer value.

Hereinafter, the present invention will be described on the assumption that the bandwidth part is activated or the bandwidth part is deactivated or the activated bandwidth part is changed using L1 (Layer 1) signaling for convenience of description. , it may also be applicable to the case of activating the bandwidth part using upper layer signaling or timer, deactivating the bandwidth part, or changing the activated bandwidth part.

According to some embodiments, the base station may set a control resource set for a downlink control channel in each bandwidth portion set for the terminal, and transmit DCI for the corresponding bandwidth portion to the corresponding control region.

In detail with reference to FIG. 6, the base station can set the bandwidth part #1 602 and the bandwidth part #2 603 to the terminal, and the control region #1 612 is assigned to the bandwidth part #1 602. It can be set, and the control area #2 (613) can be set in the bandwidth part #2 (603). The base station may transmit the DCI for the bandwidth part #1 (602) to the terminal as the control region #1 (612), and transmit the DCI for the bandwidth part #2 (603) to the terminal as the control region #2 (613).

The terminal may receive configuration information for one or a plurality of bandwidth parts from the base station. The terminal may receive configuration information about the control region in each bandwidth part from the base station. The terminal may receive an indicator for activating/deactivating one or a plurality of bandwidth parts among one or a plurality of set bandwidth parts from the base station. The terminal may receive DCI for a corresponding bandwidth part in a control region existing in one or a plurality of activated bandwidth parts.

At this time, the base station may transmit an indicator for activating or deactivating one or a plurality of bandwidth parts among one or a plurality of bandwidth parts set to the terminal or changing the activated bandwidth part), and the base station and the terminal may transmit an activated bandwidth according to the instructions of the base station Downlink and uplink signals can be transmitted and received using this part.

The base station can set a control resource set for a downlink control channel in each bandwidth part set for the terminal, and can transmit DCI for the corresponding bandwidth part to the corresponding control region.

Also, according to some embodiments, the base station may transmit DCIs for one or a plurality of other activated/deactivated bandwidth parts to a control region of one or a plurality of activated bandwidth parts. The base station may set whether to transmit the DCI for a certain bandwidth portion to the control region existing in a certain bandwidth portion to the terminal through higher layer signaling, for example, RRC or MAC CE signaling.

The terminal may receive configuration information for one or a plurality of bandwidth parts from the base station. The terminal may receive configuration information about the control region in each bandwidth part from the base station. The UE may be configured to receive DCI for a certain bandwidth portion from the base station in a control region existing in a certain bandwidth portion. The terminal may receive an indicator for activating/deactivating one or a plurality of bandwidth parts among one or a plurality of set bandwidth parts from the base station. The terminal may receive DCI for a corresponding bandwidth part or another bandwidth part in a control region existing in one or a plurality of activated bandwidth parts.

In detail with reference to FIG. 6, the base station can set the bandwidth part #1 602 and the bandwidth part #2 603 to the terminal, and the control region #1 612 is assigned to the bandwidth part #1 602. It can be set, and the control area #2 (613) can be set in the bandwidth part #2 (603).

The base station transmits DCI for bandwidth part #1 (602) to control region #1 (612) and DCI for bandwidth part #2 (603) to control region #2 (613). , DCI may be transmitted according to configuration information. The terminal may monitor and receive the DCI for the bandwidth part #1 602 in the control region #1 612 according to the settings received from the base station, and receive the DCI for the bandwidth part #2 603 in the control region #2 ( 613) can be monitored and received.

Alternatively, the base station may set the terminal to transmit both the DCI for bandwidth part #1 602 and the DCI for bandwidth part #2 603 to the control region #1 612, and transmit the DCI according to the setting information. there is. The terminal may monitor and receive DCI for bandwidth part #1 (602) and DCI for bandwidth part #2 (603) in control region #1 (612) according to the settings received from the base station.

Alternatively, the base station may set the terminal to transmit both the DCI for bandwidth part #1 (602) and the DCI for bandwidth part #2 (603) to the control region #2 (613), and transmit the DCI according to the setting information. there is. The terminal may monitor and receive DCI for bandwidth part #1 (602) and DCI for bandwidth part #2 (603) in control region #2 (613) according to the settings received from the base station.

Alternatively, the base station transmits the DCI for bandwidth part #1 (602) to the terminal as control region #1 (612) or control region #2 (613), and transmits the DCI for bandwidth part #2 (603) to control region #1 612 or control area # 2 613 can be set to be transmitted, and DCI can be transmitted according to the setting information. The terminal can monitor and receive the DCI for the bandwidth part #1 (602) in the control region #1 (612) and the control region #2 (613) according to the settings received from the base station, and in the bandwidth part #2 (603) The DCI for the control area #1 612 and control area #2 613 may be monitored and received.

In describing the present invention, the following terms are defined for convenience.

Self-bandwidth portion scheduling (hereinafter referred to as self-scheduling) refers to a case in which DCI indicating data scheduling in a predetermined bandwidth portion and data transmission/reception according to the DCI are performed in the same bandwidth portion. In other words, the base station transmits DCI through the control region #1 612 of the bandwidth part #1 602, and transmission and reception of downlink or uplink signals according to the DCI is performed in the bandwidth part #1 602. The terminal can obtain scheduling information (DCI) for data transmission/reception in a specific bandwidth part from the same bandwidth part as the bandwidth part in which the data transmission/reception is performed.

Cross bandwidth portion scheduling (hereinafter referred to as cross scheduling) refers to a case in which DCI indicating data scheduling in a predetermined bandwidth portion and data transmission/reception according to the DCI are performed in different bandwidth portions. The base station may transmit a bandwidth part for transmitting and receiving data and a DCI for indicating or setting the data in a different bandwidth part from the bandwidth part for transmitting and receiving data. The terminal can obtain scheduling information (DCI) for data transmission/reception in a specific bandwidth part in a bandwidth part different from the bandwidth part in which data transmission/reception is performed. In this case, the cross-bandwidth partial scheduling may include self-bandwidth partial scheduling. In other words, cross-bandwidth portion scheduling may include both cases in which DCI indicating data scheduling in a certain bandwidth portion and data transmission/reception according to the DCI are performed in the same bandwidth portion as well as in different bandwidth portions.

Whether self-bandwidth scheduling or cross-bandwidth partial scheduling can be set by the base station to the UE through higher-layer signaling, such as RRC signaling, and at least in the case of a UE configured with cross-bandwidth partial scheduling, the DCI of the UE can include a bandwidth portion indicator field. In the case of a terminal in which two or more bandwidth parts are set, a bandwidth part indicator field may be included in the DCI without a separate setting for self-bandwidth scheduling or cross-bandwidth part scheduling. The DCI bandwidth part indicator field may be included in the case of a terminal configured to perform a bandwidth part activation or inactivation or activation bandwidth part change operation using DCI, and whether or not the DCI includes the bandwidth part indicator field is set by the terminal through a higher signal. can receive

비트가 필요하다. 이때, 대역폭부분#1에 대한 N_RB 는 N1이고, 대역폭부분#2에 대한 N_RB는 N2이며, P는 기지국으로부터 상위 신호를 통해 설정 받는다. 만일, 상기 주파수 자원 할당 정보를 RB 할당 시작 지점과 길이를 이용하여 알려주는 경우 (주파수 자원 할당 타입 1),

의 비트수가 필요하다. 따라서, 각 대역폭부분에 대한 주파수 자원할당 정보를 지시하는 필드의 크기가 대역폭부분의 크기 또는 대역폭부분의 RB의 수에 따라 다를 수 있다. 다시 말해, N1>N2의 경우, 주파수 자원 할당 타입에 따라

또는

일 수 있으므로, 대역폭부분#1에서의 데이터 송수신을 지시하는 DCI#1의 크기가 대역폭부분#2에서의 데이터 송수신을 지시하는 DCI#2 보다 크거나 같을 수 있다. In a terminal in which two or more bandwidth parts are set, if the activation or inactivation of the bandwidth part set through the DCI or the active bandwidth part can be changed as described above, in other words, for a terminal in which a bandwidth part indicator field is included in the DCI In this case, or when the DCI for the corresponding bandwidth part and the DCI for other bandwidth parts can also be transmitted in the control area of the specific bandwidth part, the size of the DCI can be different at least according to the size of the set bandwidth part. For example, in the case of a terminal configured with bandwidth parts having different sizes, such as bandwidth part #1 602 and bandwidth part #2 603 in FIG. 6, the bandwidth part #1 602 or the bandwidth part # Size and bandwidth part of DCI indicating or setting data transmission and reception in the bandwidth part # 1 (602) because the size of the field indicating the frequency resource allocation information of 2 (603), for example, the frequency domain resource assignment field, is different DCIs indicating or setting data transmission/reception in #2 603 may have different sizes. For example, it is assumed that the number of RBs included in bandwidth part #1 602 is N1 and the number of RBs included in bandwidth part #2 603 is N2. In this case, in FIG. 6, N1>N2 may be satisfied. Upon receiving the DCI from the base station, the terminal uses the frequency resource allocation information of the DCI to receive a resource region (or PDSCH reception region) in which the terminal receives a downlink signal from the base station or a resource region used by the terminal to transmit an uplink signal to the base station ( or PUSCH transmission area) may be determined. If the frequency resource allocation information is in RBG units, that is, if the bandwidth part is divided into RBG(P) and each allocation information for the divided resource region is informed in a bitmap (frequency resource allocation type 0 ), At least

Bits are needed. At this time, N _RB for the bandwidth part #1 is N1, N _RB for the bandwidth part #2 is N2, and P is set from the base station through an upper signal. If the frequency resource allocation information is reported using the RB allocation start point and length (frequency resource allocation type 1),

number of bits is required. Accordingly, the size of a field indicating frequency resource allocation information for each bandwidth part may vary depending on the size of the bandwidth part or the number of RBs in the bandwidth part. In other words, in the case of N1>N2, according to the frequency resource allocation type

or

, the size of DCI#1 indicating data transmission/reception in bandwidth part #1 may be greater than or equal to DCI#2 indicating data transmission/reception in bandwidth part #2.

Therefore, in a terminal in which two or more bandwidth parts are set through DCI as described above, if the activation or deactivation or activation bandwidth part for the set bandwidth part can be changed through DCI as described above, that is, the bandwidth part in DCI In the case of a terminal including an indicator field, or when DCI for the corresponding bandwidth part and DCI for other bandwidth parts can also be transmitted in the control area of a specific bandwidth part, the size of the DCI may be different according to the size of the set bandwidth part. In order to receive DCIs of different sizes, the number of blind decoding times increases. In other words, since the bandwidth part #1 602 and the bandwidth part #2 603 can be set with different system parameters, the DCIs for each bandwidth part, DCI#1 and DCI#2, have different sizes. can have Therefore, when the terminal performs detection of DCI#1 and DCI#2 in the control region #1 612, blind decoding must be performed by assuming the size of DCI#1 and DCI#2, respectively. number can be increased.

Therefore, an embodiment of the present invention provides a method of reducing the number of times of blind decoding of a terminal by making the sizes of DCIs for different bandwidth parts the same, thereby effectively reducing power consumption of the terminal.

<Example 1-1>

The terminal may determine the size of the largest DCI among the sizes of the DCI for the bandwidth portion set for the carrier or serving cell as the size of the DCI for each bandwidth portion or the size of the DCI for the serving cell. . In this case, a DCI having a size relatively smaller than a DCI having the largest size may be equalized with a DCI having the largest size by adding 0 bits (zero padding). At this time, the added 0 bit may be added after the information bit of the DCI, and the 0 bit may be added before the information bit of the DCI.

In other words, in a terminal in which a plurality of bandwidth parts are set for a serving cell, if the DCI includes a bandwidth part indicator, the terminal may determine the size of the DCI for the serving cell as follows.

1. Among the DCIs for the downlink bandwidth portion in which PDSCH reception is set for the UE for the serving cell, the DCI having the largest information bit size is determined as the DCI size of the serving cell or the size of the downlink scheduling DCI of the serving cell, or

2. Among the DCIs for the uplink bandwidth portion in which PUSCH transmission is set to the UE for the serving cell, the DCI having the largest information bit size is determined as the DCI size of the serving cell or the size of the uplink scheduling DCI of the serving cell, or

3. Among the DCI for the downlink bandwidth portion in which PDSCH reception is set for the serving cell and the DCI for the uplink bandwidth portion in which PUSCH transmission is set, the DCI with the largest information bit size can be determined as the DCI size of the serving cell. there is.

In this case, the size of DCI information bits for the bandwidth portion may vary according to the size of a field indicating frequency resource allocation information for the bandwidth portion. For example, in the case of a terminal configured to allocate frequency resources for a bandwidth portion using frequency resource allocation type 1 described above, the frequency axis resource allocation indication field according to the size of the set bandwidth portion or the number of RBs in the set bandwidth portion Sizes may vary. If the size of DCI (DL assignment) for scheduling downlink signal reception and the size of DCI (UL grant) for scheduling uplink signal transmission are provided, the size of the downlink bandwidth portion set in the UE or the set bandwidth portion Since the size of the frequency-axis resource allocation indication field may all be different depending on the number of RBs as well as the size of the uplink bandwidth portion set in the UE or the number of RBs in the set bandwidth portion, the DCI having the largest size is as shown in 3 above. The DCI may have the largest size among the information bit size of the DCI for the downlink bandwidth portion in which PDSCH reception is set for the UE and the information bit size of DCI for the uplink bandwidth portion in which PUSCH transmission is configured for the UE. At this time, the DCI with the largest size is the DCI having the largest size among the information bit sizes of the DCI for the downlink bandwidth portion in which PDSCH reception is set for the terminal as in 1 above, and the uplink transmission in which PUSCH transmission is set in the terminal as in 2 above. The size of the DCI of the serving cell may be determined based on the DCI of the largest size by comparing the size of the DCI with the largest size among the information bit sizes of the DCI for the link bandwidth portion. If the downlink bandwidth part and the uplink bandwidth part are paired, the DCI having the largest size may be the DCI having the largest size among DCIs for the pair of the downlink bandwidth part and the uplink bandwidth part. Additionally, in the cases described above, the uplink bandwidth portion in which PUSCH transmission is configured may include supplementary UL (SUL). The SUL is an uplink carrier added to a specific cell to secure uplink coverage of the UE.

On the other hand, the method for determining the size of the DCI can be applied to at least a DCI for scheduling signal transmission and reception in a transmission mode and transmission setting unique to a terminal, and a DCI (fall back DCI) scheduling signal transmission and reception in a basic transmission mode and basic transmission setting. DCI) may also be applied.

The size of DCI (DCI for fall back) for scheduling signal transmission and reception in the basic transmission mode and basic transmission configuration can be determined in another method as follows.

4. The size of the fallback DCI for the bandwidth part set as the default bandwidth part or the initial access bandwidth part among the downlink bandwidth parts in which PDSCH reception is set to the UE for the serving cell is the fallback of the serving cell judged by the size of the DCI, or

5. The size of the fallback DCI for the bandwidth part set as the default bandwidth part or the initial access bandwidth part among the uplink bandwidth parts for which PUSCH transmission is set to the UE for the serving cell is the fallback of the serving cell judged by the size of the DCI, or

6. Among the DCIs 4 and 5, the fallback DCI having the largest size may be determined as the size of the fallback DCI of the serving cell.

비트가 대역폭부분 i에 대한 주파수 축 자원할당 필드의 크기인 것으로 판단할 수 있다. N_RB,i 및 P_i는 대역폭부분 i를 구성하는 RB의 수 및 대역폭부분 i에 설정된 RBG 크기이다. 주파수 자원 할당 타입 1이 설정된 단말의 경우,

비트가 대역폭부분 i에 대한 주파수 축 자원할당 필드의 크기가 되며, 주파수 자원 할당 타입 0 및 1이 모두 설정된 단말의 경우,

+1이 서빙셀에 대한 주파수 축 자원할당 필드의 크기가 된다.At this time, the size of the field indicating frequency resource allocation information among the DCI for scheduling signal transmission and reception in the basic transmission mode and basic transmission setting (DCI for fall back) is the size of the downlink bandwidth part and the uplink bandwidth part set in the terminal. The size of the fallback DCI may be determined using the size of the frequency resource allocation information field for the bandwidth portion with the largest number of RBs (or the bandwidth portion with the largest number of RBs). In other words, the size of the field indicating the frequency resource allocation information among the fallback DCI is the frequency resource for the bandwidth portion with the largest size (or the bandwidth portion with the largest number of RBs) among the downlink bandwidth portion and the uplink bandwidth portion configured for the UE. It may be the same as the size of the allocation information field. In addition, in determining the size of the DCI for the bandwidth portion of the terminal, the terminal may determine the size of the frequency axis resource allocation field included in the DCI using the embodiment 1-2. For example, a terminal configured with frequency resource allocation type 0,

It can be determined that the bit is the size of the frequency axis resource allocation field for the bandwidth portion i. N _RB,i and P _i are the number of RBs constituting bandwidth portion i and the RBG size set in bandwidth portion i. In the case of a terminal configured with frequency resource allocation type 1,

bit becomes the size of the frequency axis resource allocation field for bandwidth part i, and in the case of a terminal in which both frequency resource allocation types 0 and 1 are set,

+1 becomes the size of the frequency axis resource allocation field for the serving cell.

Referring to FIG. 6, the size of DCI#1 of bandwidth part #1 602 is M bits, and the size of DCI#2 of bandwidth part #2 603 is N bits, that is, M is N If it is larger than DCI#1, the UE transmits 0 of (M-N) bits after the information bit of DCI#2, which is smaller than DCI#1, based on the size of DCI#1, which has the largest size among DCIs for the set bandwidth portion. You can adjust the size of DCI#2 to the same size as DCI#1 by adding .

<Example 1-2>

In the terminals of Embodiments 1 to 1-1, another method of equalizing the size of the DCIs may be to set the same size of fields corresponding to frequency axis resource allocation information in the DCI for different bandwidth parts. there is. More specifically, the following method may be applied.

In the method of equalizing the size of the frequency-axis resource allocation field in the DCI for different bandwidth parts, the terminal selects the largest frequency-axis resource allocation among the sizes of the frequency-axis resource allocation field in the DCI for the set bandwidth part. Based on the size of the field, the size of the frequency axis resource allocation field of another DCI may be equally matched. At this time, the size of the frequency axis resource allocation field having the largest size is

7. The size of the largest frequency-axis resource allocation field among the sizes of frequency-axis resource allocation fields included in the DCI for the downlink bandwidth portion in which PDSCH reception is set for the UE for the serving cell, or

8. The size of the largest frequency-axis resource allocation field among the sizes of frequency-axis resource allocation fields included in the DCI for the uplink bandwidth portion in which PUSCH transmission is set to the UE for the serving cell, or

9. The size of the frequency axis resource allocation field included in the DCI for the downlink bandwidth portion in which PDSCH reception is set to the UE for the serving cell and the frequency axis resource allocation field included in DCI for the uplink bandwidth portion in which PUSCH transmission is set It may be the size of the largest frequency axis resource allocation field among sizes.

또는

비트가 서빙셀에 대한 주파수 축 자원할당 필드의 크기가 된다. 여기서 N_RB,i 및 P_i는 대역폭부분 i를 구성하는 RB의 수 및 상기 대역폭부분 i에 설정된 RBG 크기이다. 다시 말해, 상기 단말에게 설정된 대역폭부분에 포함된 RB의 수 및 RBG 크기 (P_i)에 의해 결정된 주파수 축 자원할당 필드의 크기가 가장 큰 대역폭부분에 대한 주파수 축 자원할당 필드의 크기가 상기 서빙셀에 대한 주파수 축 차원 할당 필드의 크기가 된다. 주파수 자원 할당 타입 1이 설정된 단말의 경우,

또는

비트가 서빙셀에 대한 주파수 축 자원할당 필드의 크기가 된다. 주파수 자원 할당 타입 0 및 1이 모두 설정된 단말의 경우,

+1이 서빙셀에 대한 주파수 축 자원할당 필드의 크기인 것으로 판단하는 것도 가능하다. 이때,

는 단말에게 설정된 대역폭부분 중 크기가 가장 큰 대역폭 부분 또는 단말에게 설정된 대역폭부분의 RB의 수가 가장 많은 대역폭 부분의 RB의 수이다. 이 때, 상기의 RBG 크기 P는 서빙셀에 대해 단말에게 하나의 값으로 설정되거나, 대역폭부분 별로 독립적으로 설정될 수 있으며, P의 값이 대역폭부분의 크기에 따라 다르게 설정되는 것도 가능하다.In other words, the terminal for which frequency resource allocation type 0 is set,

or

Bit becomes the size of the frequency axis resource allocation field for the serving cell. Here, N _RB,i and _Pi are the number of RBs constituting the bandwidth portion i and the RBG size set in the bandwidth portion i. In _other words, the serving cell It becomes the size of the frequency axis dimension allocation field for In the case of a terminal configured with frequency resource allocation type 1,

or

Bit becomes the size of the frequency axis resource allocation field for the serving cell. In the case of a terminal in which both frequency resource allocation types 0 and 1 are set,

It is also possible to determine that +1 is the size of the frequency axis resource allocation field for the serving cell. At this time,

Is the number of RBs in the bandwidth part having the largest size among the bandwidth parts set for the terminal or the number of RBs in the bandwidth part set for the terminal having the largest number. At this time, the RBG size P may be set to a single value for the terminal for the serving cell or may be set independently for each bandwidth part, and the value of P may be set differently according to the size of the bandwidth part.

As a specific example, the size of the frequency axis resource allocation field in DCI#1 for bandwidth portion #1 is M bits, the size of the frequency axis resource allocation field in DCI#2 for bandwidth portion #2 is N bits, , If M>N, it is assumed that the size of the frequency-axis resource allocation field of DCI#2 is M, and the DCI size can be equalized by inserting 0 of (M-N) bits. In this case, the position to insert the 0 may be inserted in the MSB or LSB of the frequency axis resource allocation field.

<Example 1-3>

In the terminals of Embodiment 1 and Embodiment 1-1 to Embodiment 1-2, another method of equalizing the size of the DCI is to set the size of a field corresponding to frequency axis resource allocation information in the DCI for different bandwidth parts. It may be the same setting.

More specifically, in addition to Example 1-2, if there is a field that does not exist in DCI#1 but does exist in DCI#2, the field that exists in DCI#2 is included in DCI#1, DCI can be equally sized.

In other words, the terminal adjusts the size of each field in another DCI based on the size of the field having the largest size among the sizes of each field included in the DCIs to match the size of the DCI, so that the size of the DCI is the same. can fit

If there is a field included in a specific DCI but not included in another DCI, it is assumed that the size of the field not included in the other DCI is 0 bits, or the field is not actually included in the other DCI but the field is included. By assuming that it is, the terminal can set the size of a field not included in other DCIs to be equal to the largest bit of the size of the field among DCIs that include the field. Of course, it is not limited to the above examples.

In addition, the position of the bit string of the information on the field may be included in the same position as the position of the bit string of the field in the DCI including the field, and therefore, the terminal can correctly interpret the information on the field. . For example, as a method of adjusting the size of a specific field in the DCI, there may be a method of inserting 0 into the MSB or LSB of the field.

Hereinafter, the frequency hopping flag of the uplink DCI will be described in more detail by way of example. Of course, the frequency hopping flag is just one example, and all other information fields, including fields that may be added to the DCI in the future, as well as other fields (eg, VRB-to-PRB mapping field) existing in the DCI will be applicable. In addition, although uplink scheduling information (or UL grant) has been described as an example, the method proposed in the present invention can be equally applied to downlink scheduling information.

The frequency hopping flag is an indicator indicating whether or not to apply frequency hopping to PUSCH transmission transmitted through DCI. In this case, the frequency hopping flag indicator field may not be included in the DCI or may be determined to be 0 bits according to the frequency resource allocation type set for the terminal.

For example, when the frequency resource allocation method for the uplink data transmission channel of the UE is set to frequency resource allocation type 0 supporting non-contiguous frequency resource allocation, the frequency hopping flag indicator field in the DCI (or UL grant) It may be determined that it is not included in the DCI or that the size of the frequency hopping flag indicator field is 0 bits. If the frequency resource allocation method for the uplink data transmission channel of the UE is set to frequency resource allocation type 1 supporting continuous frequency resource allocation, the frequency hopping flag indicator field in the DCI (or UL grant) is included in the DCI , the size of the frequency hopping flag indicator field may be determined to be 1 bit.

At this time, the terminal can determine whether frequency hopping is applied to the scheduled PUSCH transmission according to the bit indicated by the frequency hopping flag indicator. Therefore, if the setting for the frequency resource allocation method of the terminal can be set differently for each bandwidth part, or if the setting for the frequency resource allocation method of the terminal can be set differently for UL or SUL, the specific field of the DCI The DCI size cannot be equally matched only by the size matching method.

More specifically, it is assumed that DCI#1 is a DCI for configuring uplink transmission for UL, and DCI#2 is a DCI for configuring uplink transmission for SUL. At this time, DCI#1 and DCI#2 can be distinguished through the UL/SUL delimiter field in DCI#1 and DCI#2. If the uplink frequency resource allocation type for UL is set to 0 and the uplink frequency resource allocation type for SUL is set to 1, the terminal includes the frequency hopping flag indicator field in DCI#1. Otherwise, it is determined that the size of the frequency hopping flag indicator field is 0 bits, DCI#2 includes the frequency hopping flag indicator field in the DCI, and it can be determined that the size of the frequency hopping flag indicator field is 1 bit. . In other words, in order to equalize the size of the DCI, the terminal, according to the specific setting as described above, includes all of the indicator fields not included in the DCI field or fields whose size is 0 bits, and the fields included in each DCI. The size of fields included in all other DCIs can be matched according to the size of the largest field among sizes.

In the above case, DCI#1 does not include a frequency hopping flag indicator field, but DCI#2 includes a 1-bit frequency hopping flag indicator field, so the terminal has the same size as DCI#2 in DCI#1. It is considered that the frequency hopping flag indicator field is included in the same position as DCI#2, and the size of DCI#1 can be determined. In other words, the terminal may pad zero to the frequency hopping flag bit position of DCI#1. In addition, after detecting the DCI#1, the terminal may ignore the information of the frequency hopping flag indicator field.

As another example, a bandwidth partial indicator is described as follows. The bandwidth part indicator is an indicator indicating a bandwidth part in which DCI configures PDSCH or PUSCH transmission. Depending on the number of bandwidth parts set for a cell, the bandwidth part indicator may not exist or may have a size of 1 bit or 2 bits. . For example, in the case of a terminal in which a bandwidth part is not set for a cell or only one bandwidth part is set, it is determined that the bandwidth part indicator is not included in the DCI or it is determined that the size of the bandwidth part indicator is 0 bits. can If two bandwidth parts are set, the terminal may determine that the size of the bandwidth part indicator in the DCI is 1 bit. Similarly, in the case of a terminal configured with 3 or 4 bandwidth parts, it can be determined that the size of the bandwidth part indicator in the DCI is 2 bits. Therefore, if the number of bandwidth parts configured for the terminal can be set differently for UL or SUL, the size of the branch branch of the bandwidth part of DCI may be different.

More specifically, it is assumed that DCI#1 is a DCI for configuring uplink transmission for UL, and DCI#2 is a DCI for configuring uplink transmission for SUL. At this time, DCI#1 and DCI#2 can be distinguished through the UL/SUL delimiter field in DCI#1 and DCI#2. If the number of uplink bandwidth parts for UL is set to 2 and the number of uplink bandwidth parts for SUL is set to 1, the UE either does not include a bandwidth part indicator field in DCI#2, or It can be determined that the size of the bandwidth part indicator field is 0 bits. In the above case, according to the method proposed by the present invention, the terminal determines that the bandwidth part indicator field of DCI#2 exists and the size is 1 bit, so that the size of DCI#1 and DCI#2 can be equalized. . At this time, the terminal receiving DCI#2 determines that 0 is inserted in the bandwidth part indicator field of DCI#2 to match the size, and can ignore the information indicated by the bandwidth part indicator field of DCI#2.

In other words, the terminal can acquire the remaining information except for the bandwidth partial indicator field information among the scheduling information indicated by DCI#2, and receive or transmit data through it. If the number of uplink bandwidth parts for the UL is set to 4 and the number of uplink bandwidth parts for the SUL is set to 2, the terminal has a bandwidth part indicator field size of DCI#1 2 bits, It can be determined that the size of the bandwidth part indicator field of DCI#2 is 1 bit. At this time, in order to match the size of DCI#1 and DCI#2, the terminal can insert 0 into the bandwidth part indicator field of DCI#2, and the position to insert 0 is in the MSB or LSB of the bandwidth part indicator field can be inserted.

As described above, when the size of the DCI is matched by matching the size of each field of the plurality of DCIs to the same size for the case where the size of the DCI is different due to the difference in configuration information for the UL and the SUL, the terminal receives the DCI and DCI After determining whether is DCI for UL or DCI for SUL, the size of each field can be correctly interpreted. In other words, when the method of equalizing a plurality of DCI sizes through the above embodiments 1-2 to 1-3 is applied, the terminal receives the DCI and locates the UL/SUL indicator field in the received DCI information and interpret the remaining information of the received DCI according to the information indicated by the UL or SUL indicator indicated by the UL/SUL indicator field. In other words, in the above example, after receiving the DCI, if the received DCI information indicates that the DCI is the DCI for the SUL, the terminal ignores the bandwidth part indicator information in the DCI (when one bandwidth part is set in the SUL). , it is determined that one 0 is inserted in the MSB or LSB (when two bandwidth parts are set in SUL), and the DCI information must be correctly interpreted or determined.

At this time, when the method of equalizing the sizes of a plurality of DCIs through the above embodiment 1-1 is applied, the terminal cannot correctly determine the bit position of the UL/SUL indicator field in the received DCI. Therefore, when the above embodiment 1-1 is applied, the UL/SUL indicator field should be positioned before a field having a different field size according to at least UL/SUL. In other words, at least the location of the UL/SUL indicator field should be independent of UL/SUL. For example, the UL/SUL indicator must be located at the beginning of the DCI or before the bandwidth part indicator field.

A base station operation according to an embodiment of the present invention will be described using FIG. 7 as follows. The base station may transmit bandwidth portion setting information to the terminal in step 700. At this time, the bandwidth portion setting information may be transmitted to the terminal through an upper signal, and the setting information shown in Table 3 may be included as the bandwidth portion setting information. The base station can determine the size of the DCI transmitted to the terminal to schedule data transmission/reception through the bandwidth portion setting information set for the terminal in step 700. For example, the base station schedules downlink data reception or uplink data transmission through the bandwidth part based on the size of the bandwidth part set for the serving cell or the bandwidth part in which the number of RBs included in the bandwidth part is the largest. It is possible to determine the size of the DCI required for In other words, based on the DCI of the largest size among the sizes of the DCI transmitted to schedule data transmission and reception for the serving cell or the DCI for the bandwidth portion with the largest number of RBs included in the bandwidth portion or the size of the bandwidth portion, the terminal determines the DCI size of the serving cell, and among the DCIs for the set bandwidth portion, inserts 0 bit into a DCI smaller than the DCI size to equalize the size of the DCIs for the set bandwidth portion. Thereafter, the base station may schedule data transmission and reception by transmitting the DCI of the determined size to the terminal through step 720.

A terminal operation according to an embodiment of the present invention will be described using FIG. 8 as follows. In step 800, the terminal may receive configuration information about the bandwidth part from the base station. At this time, the bandwidth portion setting information may be transmitted from the base station through an upper signal, and the setting information shown in Table 3 may be included in the bandwidth portion setting information. Based on the bandwidth portion setting information received from the base station in step 800, the terminal can determine the size of the DCI transmitted by the base station in order to receive scheduling of data transmission and reception from the base station. For example, the terminal receives downlink data or transmits uplink data through the bandwidth part based on the size of the bandwidth part set for the serving cell by the base station or the bandwidth part where the number of RBs included in the bandwidth part is the largest. It is possible to determine the size of DCI required to receive scheduling. In other words, based on the DCI of the largest size among the sizes of DCIs transmitted to receive scheduling of data transmission and reception for the serving cell or the size of the bandwidth portion or the DCI for the bandwidth portion with the largest number of RBs included in the bandwidth portion, the terminal determines the DCI size of the serving cell, and among the DCIs for the set bandwidth portion, inserts 0 bit into a DCI smaller than the DCI size to equalize the size of the DCIs for the set bandwidth portion. After that, the terminal detects DCI of the determined size in the preset control area through step 820. If it is determined in step 830 that DCI has been received, in step 840, the terminal can transmit and receive data in the bandwidth portion, time and frequency resource domains set in the DCI. If it is determined that DCI has not been received in step 830, the terminal repeats the DCI detection operation in step 830.

9 is a block diagram showing the internal structure of a base station according to some embodiments. As shown in FIG. 9, the base station of the present invention may include a processor 901, a transceiver 902, and a memory 903. can The processor 901, transceiver 902, and memory 903 of the base station may operate according to the above-described communication method of the base station. However, components of the base station are not limited to the above-described examples. For example, a base station may include more or fewer components than those described above. In addition, the processor 901, the transceiver 902, and the memory 903 may be implemented as a single chip. Also, the processor 901 may be at least one.

The processor 901 may control a series of processes so that the base station can operate according to the above-described embodiment of the present invention. For example, the processor 901 may differently control other components of the base station according to a bandwidth portion setting method, a bandwidth portion scheduling method, a DCI transmission method, and the like according to an embodiment of the present invention. In addition, the processor 901 may control other elements of the base station to transmit various additional indicators and setting information as needed. The base station receiving unit and the base station transmitting unit may collectively be referred to as a transceiver 902 in an embodiment of the present invention. The transmitting and receiving unit 902 may transmit and receive signals to and from the terminal. A signal transmitted and received with the terminal may include control information and data. To this end, the transceiver 902 may include an RF transmitter that up-converts and amplifies the frequency of a transmitted signal, and an RF receiver that amplifies a received signal with low noise and down-converts its frequency. However, this is only one embodiment of the transceiver 902, and components of the transceiver 902 are not limited to the RF transmitter and the RF receiver. In addition, the transceiver 902 may receive a signal through a wireless channel, output the signal to the processor 901, and transmit the signal output from the processor 901 through a wireless channel.

The memory 903 may store programs and data necessary for the operation of the base station. Also, the memory 903 may store control information or data included in a signal obtained from the base station. The memory 903 may include a storage medium such as a ROM, a RAM, a hard disk, a CD-ROM, and a DVD, or a combination of storage media.

10 is a block diagram showing the internal structure of a terminal according to an embodiment of the present invention. As shown in FIG. 10, the terminal of the present invention may include a processor 1001, a transceiver 1002, and a memory 1003. The processor 1001, transceiver 1002, and memory 1003 of the terminal may operate according to the communication method of the terminal described above. However, the components of the terminal are not limited to the above-described examples. For example, a terminal may include more or fewer components than the aforementioned components. In addition, the processor 1001, the transceiver 1002, and the memory 1003 may be implemented as a single chip. Also, the processor 1001 may be at least one.

The processor 1001 may control a series of processes in which the terminal may operate according to the above-described embodiment of the present invention. For example, decoding operations for a downlink control channel and a data channel of a UE may be differently controlled according to information such as a bandwidth portion setting method, a bandwidth portion scheduling method, and a DCI reception method according to an embodiment of the present invention. .

A terminal receiving unit and a terminal transmitting unit may be collectively referred to as the transmitting/receiving unit 1002 in an embodiment of the present invention. The transmitting/receiving unit may transmit/receive signals with the base station. A signal transmitted and received with the base station may include control information and data. To this end, the transceiver 1002 may include an RF transmitter for up-converting and amplifying the frequency of a transmitted signal, and an RF receiver for low-noise amplifying a received signal and down-converting its frequency. However, this is only one embodiment of the transceiver 1002, and components of the transceiver 1002 are not limited to the RF transmitter and the RF receiver. In addition, the transceiver 1002 may receive a signal through a wireless channel, output the signal to the processor 1001, and transmit the signal output from the processor 1001 through a wireless channel.

The memory 1003 may store programs and data required for operation of the terminal. Also, the memory 1003 may store control information or data included in a signal obtained from the terminal. The memory 1006 may be composed of a storage medium such as a ROM, a RAM, a hard disk, a CD-ROM, and a DVD, or a combination of storage media.

On the other hand, the embodiments of the present invention disclosed in the present specification and drawings are only presented as specific examples to easily explain the technical content of the present invention and help understanding of the present invention, and are not intended to limit the scope of the present invention. That is, it is obvious to those skilled in the art that other modified examples based on the technical idea of the present invention can be implemented. In addition, each of the above embodiments may be operated in combination with each other as needed. In addition, each of the above embodiments can be operated in combination with each other as needed. For example, parts of each embodiment may be combined with each other to operate a base station and a terminal. In addition, although the above-described embodiments have been presented based on the NR system, other modified examples based on the technical ideas of the corresponding embodiments may be implemented in other systems such as FDD or TDD LTE systems.

In addition, the present specification and drawings disclose preferred embodiments of the present invention, and although specific terms are used, they are only used in a general sense to easily explain the technical content of the present invention and help understanding of the present invention. It is not intended to limit the scope of the invention. It is obvious to those skilled in the art that other modified examples based on the technical spirit of the present invention can be implemented in addition to the embodiments disclosed herein.

Claims (16)

A method for setting downlink control information of a base station in a wireless communication system,
Transmitting a configuration message including first information on an uplink (UL) and second information on a supplementary uplink (SUL) to a terminal;
determining, as a reference DCI size, a size of the first DCI having a larger size among a first Downlink Control Information (DCI) for the UL and a second DCI for the SUL;
adjusting the second DCI to the reference DCI size based on the number of bandwidth parts (BWPs) configured for each of the UL and the SUL; and
Transmitting at least one of the first DCI and the adjusted second DCI to the terminal,
When the number of BWPs configured for the UL is plural and the number of BWPs configured for the SUL is one, a BWP indicator field is included in the adjusted second DCI;
Characterized in that the size of the BWP indicator field of the adjusted second DCI follows the number of BWPs configured for the UL.
According to claim 1,
The UL / SUL indicator field included in each of the first DCI and the adjusted second DCI is located before the BWP indicator field.
According to claim 1,
The step of adjusting the second DCI to the reference DCI size,
And adjusting the size of the frequency axis resource allocation field in the second DCI to be the same as the size of the frequency axis resource allocation field in the first DCI.
According to claim 1,
The step of adjusting the second DCI to the reference DCI size,
And adjusting a field that does not exist in the second DCI but exists in the first DCI to be included in the second DCI.
A method for setting downlink control information of a terminal in a wireless communication system,
Receiving a configuration message including first information on an uplink (UL) and second information on a supplementary uplink (SUL) from a base station;
Identifying a size of a first downlink control information (DCI) for the UL and a size of a second DCI for the SUL based on the number of bandwidth parts (BWPs) configured for each of the UL and the SUL;
Based on the identification, if the size of the first DCI is greater than the size of the second DCI, determining the size of the first DCI as a reference DCI size;
performing blind decoding on at least one of the first DCI and a second DCI adjusted based on the reference DCI size, on a signal received from the base station, based on the reference DCI size; and
Transmitting uplink data based on a DCI detected according to the blind decoding among the first DCI and the second DCI;
When the number of BWPs configured for the UL is plural and the number of BWPs configured for the SUL is one, a BWP indicator field is included in the adjusted second DCI;
Characterized in that the size of the BWP indicator field of the adjusted second DCI follows the number of BWPs configured for the UL.
According to claim 5,
The UL / SUL indicator field included in each of the first DCI and the adjusted second DCI is located before the BWP indicator field.
According to claim 5,
The second DCI adjusted based on the reference DCI size,
The size of the frequency axis resource allocation field in the second DCI is adjusted to be the same as the size of the frequency axis resource allocation field in the first DCI. According to claim 5,
The second DCI adjusted based on the reference DCI size,
Although not present in the second DCI, a field present in the first DCI is adjusted to be included in the second DCI. In a base station for setting downlink control information in a wireless communication system,
transceiver; and
It includes a processor, the processor comprising:
Transmitting a configuration message including first information for an uplink (UL) and second information for a supplementary uplink (SUL) to a terminal through the transceiver,
determining a size of the first DCI having a larger size among a first downlink control information (DCI) for the UL and a second DCI for the SUL as a reference DCI size;
Adjusting the second DCI based on the number of bandwidth parts (BWPs) configured for each of the UL and the SUL,
Transmitting at least one of the first DCI and the adjusted second DCI to the terminal through the transceiver,
When the number of BWPs configured for the UL is plural and the number of BWPs configured for the SUL is one, a BWP indicator field is included in the adjusted second DCI;
Characterized in that, the size of the BWP indicator field of the adjusted second DCI follows the number of BWPs configured for the UL.
According to claim 9,
The UL / SUL indicator field included in each of the first DCI and the adjusted second DCI is located before the BWP indicator field.
According to claim 9,
the processor,
Adjusting the size of the frequency axis resource allocation field in the second DCI to be the same as the size of the frequency axis resource allocation field in the first DCI, the base station. According to claim 9,
the processor,
A base station that does not exist in the second DCI, but adjusts a field that exists in the first DCI to be included in the second DCI. In a terminal for setting downlink control information in a wireless communication system,
transceiver; and
It includes a processor, the processor comprising:
Receiving a configuration message including first information on an uplink (UL) and second information on a supplementary uplink (SUL) from a base station through the transceiver,
Based on the number of bandwidth parts (BWPs) configured for each of the UL and the SUL, a size of a first downlink control information (DCI) for the UL and a size of a second DCI for the SUL are identified,
Based on the identification, when the size of the first DCI is greater than the size of the second DCI, determining the size of the first DCI as a reference DCI size;
Blind decoding of at least one of the first DCI and a second DCI adjusted based on the reference DCI size is performed on a signal received from the base station based on the reference DCI size;
Transmits uplink data based on a DCI detected according to blind decoding among the first DCI and the second DCI through the transceiver,
When the number of BWPs configured for the UL is plural and the number of BWPs configured for the SUL is one, a BWP indicator field is included in the adjusted second DCI;
Characterized in that the size of the BWP indicator field of the adjusted second DCI follows the number of BWPs configured for the UL, the terminal
According to claim 13,
The UL / SUL indicator field included in each of the first DCI and the adjusted second DCI is located before the BWP indicator field.
According to claim 13,
The second DCI adjusted based on the reference DCI size,
The size of the frequency axis resource allocation field in the second DCI is adjusted to be the same as the size of the frequency axis resource allocation field in the first DCI. According to claim 13,
The second DCI adjusted based on the reference DCI size,
The terminal, which does not exist in the second DCI, but is adjusted so that a field present in the first DCI is included in the second DCI.

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