Method and apparatus for transmitting downlink control information in a wireless communication system

Abstract

The disclosure relates to a communication method and system for fusing a fifth generation (5G) communication system for supporting a higher data rate than a fourth generation (4G) system with an Internet of Things (IoT) technology. A method of a base station is provided. The method includes transmitting configuration information about a first bandwidth part (BWP) and a second BWP to a terminal, generating first downlink control information (DCI) for the second BWP so that a size of the first DCI for the second BWP corresponds to a size of second DCI for the first BWP, and transmitting the first DCI for the second BWP on a control region of the first BWP.

Description

[0001] This application is a divisional application of the invention patent application filed on July 12, 2018, with application number 201880047214.0. Technical Field

[0002] This disclosure generally relates to a wireless communication system, and more specifically, to a method and apparatus for transmitting downlink control information in a next-generation mobile communication system. Background Technology

[0003] Efforts have been made to develop improved 5G or pre-5G communication systems, also known as "super 4G networks" or "post-LTE systems." 5G communication systems are considered to be implemented in higher frequency (mmWave) bands (e.g., the 60GHz band) to achieve higher data rates. To reduce radio wave propagation loss and increase transmission distance, beamforming, massive MIMO, full-size MIMO (FD-MIMO), array antennas, analog beamforming, and massive MIMO technologies have been considered for use with 5G communication systems. Furthermore, in 5G communication systems, development is underway to improve system networks based on advanced small cell networks, cloud radio access networks (RAN), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, mobile networks, cooperative communication, cooperative multipoint (CoMP), and receiver interference cancellation. In 5G systems, hybrid frequency shift keying (FSK) with orthogonal amplitude modulation (QAM) (FQAM) and sliding window superposition coding (SWSC) as advanced coding and modulation (ACM), as well as filter bank multicarrier (FBMC), non-orthogonal multiple access (NOMA) and sparse code multiple access (SCMA) as advanced access technologies, have been considered.

[0004] The Internet is now evolving into the Internet of Things (IoT), in which distributed entities, such as things, can exchange and process information without human intervention. The Internet of Everything (IoE), a combination of IoT technology and big data processing technology connected to cloud servers, has emerged. With technological elements such as sensing technology, wired / wireless communication and network infrastructure, service interface technology, and security technology being required for IoT implementation, sensor networks, machine-to-machine (M2M) communication, and machine-type communication (MTC) have recently been explored. Such an IoT environment can provide intelligent Internet technology services that create new value for human life by collecting and analyzing data generated between connected things. Through the convergence and integration of existing information technology (IT) with various industrial applications, IoT can be applied to a wide range of fields, including smart homes, smart buildings, smart cities, smart or connected cars, smart grids, healthcare, smart appliances, and advanced medical services.

[0005] Various attempts have been made to apply 5G communication systems to IoT networks. For example, technologies such as sensor networks, MTC, and M2M communication can be implemented using beamforming, MIMO, and array antennas. The application of cloud RAN, as a big data processing technology, can also be seen as an example of the convergence between 5G and IoT technologies.

[0006] At the same time, methods and devices for transmitting downlink control information in next-generation mobile communication systems are needed, based on the latest advancements in Long Term Evolution (LTE) and advanced LTE systems. Summary of the Invention

[0007] Technical issues

[0008] Unlike existing wireless communication systems, 5G wireless communication systems are designed to support not only services requiring high data rates, but also services with very low transmission latency and high connection density. In these cases, it is necessary to provide a variety of services involving different transmission and reception technologies and parameters within a single system to meet diverse user requirements and needs. Furthermore, it is important to design the system for forward compatibility so that added services are not limited by the current system. 5G wireless communication systems are designed to support subcarrier spacing with multiple parameter sets (numerology), thus utilizing time and frequency resources more flexibly than existing LTE systems.

[0009] To achieve ultra-high-speed data services of several Gbps in 5G systems, signals can be transmitted and received with ultra-wide bandwidths ranging from tens to hundreds of MHz or even several GHz. The bandwidth supported by a terminal can differ from the system bandwidth. Specific bandwidth portions can be configured for the terminal to support signal transmission and reception. Based on the proportional relationship between power consumption and transmit / receive bandwidth, different bandwidth portions can be configured for the terminal's operation to efficiently manage power consumption by adjusting transmit and receive bandwidth. To support subcarriers of different sizes, one or more bandwidth portions can be configured for the terminal, and the subcarrier spacing of each bandwidth portion can be set differently. The base station can configure bandwidth portions for the terminal and transmit and receive signals through the corresponding bandwidth portions for various purposes. Bandwidth portions can be configured via various system parameters.

[0010] To schedule data to be transmitted to the terminal, the base station can determine the bandwidth portion to be used and send different downlink control messages based on the configuration information of the corresponding bandwidth portion. More specifically, the base station can configure one or more bandwidth portions for the terminal and can use one or more of the configured bandwidth portions to transmit signals. The scheduling information for data to be transmitted via each bandwidth portion can vary depending on various system parameters set for the bandwidth portion, such as bandwidth size, slot duration, and subcarrier spacing. Therefore, one or more different downlink control messages can be sent.

[0011] Technical solution

[0012] Therefore, one aspect of this disclosure provides a method for transmitting downlink control information for efficient system operation in various signal transmission and reception operations using bandwidth portions. A base station can transmit downlink control information to a terminal for data transmission via the same bandwidth portion. A base station can transmit downlink control information to a terminal for data transmission via different bandwidth portions. A base station can transmit downlink control information to a terminal for data transmission via multiple bandwidth portions. To support the above operations, additional downlink control information fields may be required, or different interpretations of the same downlink control information field may be required. In view of this, the present invention provides a downlink control information field and a method and apparatus for correspondingly transmitting downlink control information.

[0013] According to this disclosure, a method for use by a base station is provided. The method includes: sending configuration information about a first bandwidth portion (BWP) and a second BWP to a terminal; generating first downlink control information (DCI) for the second BWP such that the size of the first DCI for the second BWP corresponds to the size of the second DCI for the first BWP; and transmitting the first DCI for the second BWP over the control area of ​​the first BWP.

[0014] According to this disclosure, a base station is provided. The base station includes: a transceiver configured to transmit and receive signals; and a controller configured to transmit configuration information about a first bandwidth portion (BWP) and a second BWP to a terminal, generate first downlink control information (DCI) for the second BWP such that the size of the first DCI for the second BWP corresponds to the size of the second DCI for the first BWP, and transmit the first DCI for the second BWP over the control area of ​​the first BWP.

[0015] According to this disclosure, a method for use by a terminal is provided. The method includes: receiving configuration information about a first bandwidth portion (BWP) and a second BWP from a base station; decoding a first DCI for the second BWP on a control area of ​​the first BWP based on the size of a second downlink control information (DCI) for the first BWP; and identifying information fields included in the first DCI for the second BWP.

[0016] According to this disclosure, a terminal is provided. The terminal includes: a transceiver configured to transmit and receive signals; and a controller configured to receive configuration information from a base station regarding a first bandwidth portion (BWP) and a second BWP, decode a first DC for the second BWP on a control area of ​​the first BWP based on the size of a second downlink control information (DCI) for the first BWP, and identify information fields included in the first DCI for the second BWP.

[0017] Beneficial effects of the invention

[0018] According to this disclosure, the terminal can operate on the bandwidth portion of the 5G communication system using ultra-wideband operation, and the 5G communication system can be operated more efficiently. This can reduce the number of blind decodes performed by the terminal and reduce the terminal's power consumption. Attached Figure Description

[0019] The above and other aspects, features and advantages of certain embodiments of the present disclosure will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, wherein:

[0020] Figure 1 This is a diagram of the time-frequency domain in LTE according to an embodiment;

[0021] Figure 2 This is a diagram illustrating the Physical Downlink Control Channel (PDCCH) and the Enhanced PDCCH (EPDCCH) that serve as downlink control channels in Long Term Evolution (LTE) according to an embodiment;

[0022] Figure 3 This is a diagram of the 5G downlink control channel according to an embodiment;

[0023] Figure 4 This is a diagram illustrating resource area allocation for a 5G downlink control channel according to an embodiment;

[0024] Figure 5 This is a diagram illustrating the spacing of many subcarriers considered in 5G communication according to an embodiment;

[0025] Figure 6 This is a diagram illustrating the bandwidth portion considered in 5G communication according to an embodiment;

[0026] Figure 7 This is an illustration of a terminal according to an embodiment; and

[0027] Figure 8 This is a diagram of a base station according to an embodiment. Detailed Implementation

[0028] Embodiments of this disclosure will be described below with reference to the accompanying drawings. However, the embodiments of this disclosure are not limited to the specific embodiments and should be construed as including all modifications, alterations, equivalent devices and methods, and / or alternative embodiments of this disclosure. In the description of the drawings, similar reference numerals are used for similar elements.

[0029] As used herein, the terms “having,” “may have,” “include,” and “may include” indicate the presence of a corresponding feature (e.g., an element such as a numerical value, function, operation, or component) and do not exclude the presence of additional features.

[0030] As used herein, the terms “A or B,” “at least one of A and / or B,” or “one or more of A and / or B” include all possible combinations of the items listed with them. For example, “A or B,” “at least one of A and B,” or “at least one of A or B” means (1) including at least one A, (2) including at least one B, or (3) including both at least one A and at least one B.

[0031] As used herein, terms such as “first” and “second” can be used to refer to the corresponding components regardless of importance or order, and are used to distinguish one component from another without limiting the components. These terms can be used for the purpose of distinguishing one element from another. For example, “first user equipment” and “second user equipment” can refer to different user equipment regardless of order or importance. For example, without departing from the scope of this disclosure, a first element can be referred to as a second element, and similarly, a second element can be referred to as a first element.

[0032] It will be understood that when an element (e.g., a first element) is "operably or communicatively coupled" or "operably or communicatively coupled to" another element (e.g., a second element), the element can be directly coupled to / directly coupled to the other element, and an element (e.g., a third element) may be inserted between the element and the other element. Conversely, it will be understood that when an element (e.g., a first element) is "directly coupled" or "directly coupled to" or "directly connected to" another element (e.g., a second element), there is no element (e.g., a third element) inserted between the element and the other element.

[0033] As used herein, the expression “configured as (or set to)” can be used interchangeably with “suitable for,” “capable of,” “designed to,” “adapted to,” “enabled,” or “able to” depending on the context. The term “configured as (or set to)” does not necessarily mean “specifically designed for” at the hardware level. Instead, the expression “a device configured as…” can mean that the device is “capable” in a particular context to work with other devices or components to… For example, “a processor configured as (or set to) perform A, B, and C” can mean a dedicated processor (e.g., an embedded processor) for performing the respective operations, or a general-purpose processor (e.g., a central processing unit (CPU) or application processor (AP)) capable of performing the respective operations by executing one or more software programs stored in a memory device.

[0034] The terminology used in describing the various embodiments of this disclosure is for the purpose of describing particular embodiments and is not intended to limit this disclosure. As used herein, the singular form is also intended to include the plural form unless the context clearly indicates otherwise. Unless otherwise defined, all terms used herein (including technical or scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art. Terms defined in a general dictionary should be interpreted as having the same or similar meaning as in the context of the related art and should not be construed as having an ideal or exaggerated meaning unless clearly defined herein. As appropriate, even terms defined in this disclosure should not be construed as excluding embodiments of this disclosure.

[0035] As used herein, the term "module" can, for example, mean a unit comprising one or more of hardware, software, and firmware, or a combination of two or more of them. "Module" can be used interchangeably with terms such as "unit," "logic," "logic block," "component," or "circuit." A "module" can be the smallest unit of an integrated constituent element or a portion thereof. A "module" can be the smallest unit for performing one or more functions or a portion thereof. A "module" can be implemented mechanically or electronically. For example, a "module" according to this disclosure can include at least one of an application-specific integrated circuit (ASIC) chip, a field-programmable gate array (FPGA), and a programmable logic device for performing operations known or to be developed below.

[0036] Electronic devices according to this disclosure may include at least one of, for example, smartphones, tablet PCs, mobile phones, video phones, e-book readers, desktop PCs, laptop PCs, netbooks, workstations, servers, personal digital assistants (PDAs), portable multimedia players (PMPs), MPEG-1 audio layer 3 (MP3) players, mobile medical devices, cameras, and wearable devices. Wearable devices may include at least one of the following types: accessory-type (e.g., watches, rings, bracelets, anklets, necklaces, glasses, contact glasses, or head-mounted devices (HMDs)), fabric or clothing integrated type (e.g., electronic clothing), body-installed type (e.g., skin pads or tattoos), and bio-implantable type (e.g., implantable circuitry).

[0037] The electronic device may be a household appliance. Household appliances may include, for example, a television, a digital video disc (DVD) player, an audio device, a refrigerator, an air conditioner, a vacuum cleaner, an oven, a microwave oven, a washing machine, an air purifier, a set-top box, a home automation control panel, a security control panel, a TV box (e.g., Samsung HomeSync™, Apple TV™, or Google TV™), a game console (e.g., Xbox™ and PlayStation™), an electronic dictionary, an electronic key, a camera, and an electronic photo frame.

[0038] Electronic devices may include at least one of the following: various medical devices (e.g., various portable medical measurement devices (blood glucose monitoring devices, heart rate monitoring devices, blood pressure measuring devices, body temperature measuring devices, etc.), magnetic resonance angiography (MRA), magnetic resonance imaging (MRI), computed tomography (CT) machines, and ultrasound machines), navigation devices, global positioning system (GPS) receivers, event data loggers (EDR), flight data loggers (FDR), vehicle infotainment devices, electronic devices for ships (e.g., navigation devices and gyrocompasses for ships), avionics, security devices, automotive mainframes, home robots or industrial robots, automated teller machines (ATMs) in banks, point-of-sale (POS) devices in stores, or IoT devices (e.g., light bulbs, various sensors, electricity or gas meters, sprinkler systems, fire alarms, thermostats, streetlights, toasters, sporting goods, hot water tanks, heaters, boilers, etc.).

[0039] Electronic devices may include at least one of furniture or building / structure components, electronic boards, electronic signature receiving devices, projectors, and various measuring instruments (e.g., water meters, electricity meters, gas meters, and radio wave meters). Electronic devices may be combinations of one or more of the aforementioned devices. Electronic devices may also be flexible devices. Furthermore, electronic devices are not limited to the aforementioned devices and may include electronic devices developed according to new technologies.

[0040] In the following description, the electronic device will be referenced in the accompanying drawings. In this disclosure, the term "user" may refer to a person using the electronic device or the device using the electronic device (e.g., an artificial intelligence electronic device).

[0041] The following description is based on LTE and 5G systems. However, those skilled in the art will understand that the subject matter of this disclosure can be applied to other communication systems with similar technical backgrounds and channel configurations without significant modifications that depart from the scope of this disclosure.

[0042] Compared to early wireless communication systems that only provided voice-oriented services, advanced broadband wireless communication systems (such as 3GPP High-Speed ​​Packet Access (HSPA) systems, LTE or Evolved Universal Terrestrial Radio Access (E-UTRA) systems, advanced LTE (LTE-A) systems, LTE Pro systems, 3GPP2 High-Rate Packet Data (HRPD) systems, Ultra Mobile Broadband (UMB) systems, and IEEE 802.16e-based systems) can provide high-speed and high-quality packet data services.

[0043] In LTE systems, a representative example of broadband wireless communication systems, Orthogonal Frequency Division Multiplexing (OFDM) is used for the downlink, while Single-Carrier Frequency Division Multiple Access (SC-FDMA) is used for the uplink. The uplink refers to the radio link through which a terminal (User Equipment (UE) or Mobile Station (MS)) transmits data or control signals to a base station (BS or eNode B), while the downlink refers to the radio link through which the base station transmits data or control signals to the terminal. In such multiple access schemes, time-frequency resources used to carry user data or control information are allocated to ensure they do not overlap (i.e., maintain orthogonality), thereby identifying the data or control information of a specific user.

[0044] As a post-LTE communication system, 5G communication systems should be able to support services that meet diverse requirements, taking into account the various needs of users and service providers. 5G communication systems can be designed to support enhanced mobile broadband (eMBB), massive machine-type communication (mMTC), and ultra-reliable low-latency communication (URLLC).

[0045] eMBB offers higher data rates than those supported by existing LTE, LTE-A, or LTE-Pro systems. For eMBB in 5G communication systems, base stations should be able to provide a peak data rate of 20Gbps in the downlink and 10Gbps in the uplink. 5G communication systems provide improved user-perceived data rates for terminals. Meeting these requirements necessitates improvements in various transmit and receive technologies, including enhanced MIMO. While current LTE systems use a maximum transmission bandwidth of 20MHz in the 2GHz band, 5G communication systems can meet the required data transmission rates by using transmission bandwidths greater than 20MHz in the bands between 3GHz and 6GHz or between 6GHz and higher frequencies.

[0046] In 5G communication systems, mMTC supports application services such as IoT. To efficiently support IoT services, mMTC requires support for a large number of terminals within a cell, extending terminal coverage, increasing terminal battery life, and reducing terminal costs. IoT must be able to support a large number of terminals within a cell (e.g., 1,000,000 terminals / km²) to provide communication services for sensors and components attached to various devices. Furthermore, due to the nature of the service, mMTC is more likely to cover shadowed areas, such as building basements and areas not covered by the cell, thus requiring wider coverage than other 5G services. Low-cost terminals are likely to be used in mMTC, and because it is difficult to frequently replace terminal batteries, very long battery life (e.g., 10 to 15 years) is required.

[0047] URLLC, as a cellular-based mission-critical wireless communication service for specific purposes, is a service that can be used for remote control of robots or machinery, industrial automation, unmanned aerial vehicles, remote healthcare, and emergency notifications, and should be capable of ultra-reliable and low-latency communication. As required, URLLC services may need to support both air interface latency of less than 0.5 ms and packet error rates of 10⁻⁵ or less. Therefore, for URLLC, the Transmission Time Interval (TTI) should be shorter than that of other 5G services, and resources should be allocated in a wide bandwidth for the reliability of the communication link.

[0048] The three 5G services (eMBB, URLLC, and mMTC) can be multiplexed and transmitted within a single system. Here, different transmission and reception technologies and parameters can be used for 5G services to meet different requirements.

[0049] Figure 1This is a diagram of the time-frequency domain according to an embodiment, which serves as the radio resource for transmitting data or control channels in the downlink of an LTE system.

[0050] exist Figure 1 In the diagram, the horizontal axis represents the time domain, and the vertical axis represents the frequency domain. In the time domain, the smallest unit for transmission is an OFDM symbol. Nsymb OFDM symbols 101 constitute a time slot 102, and two time slots constitute a subframe 103. The length of a time slot is 0.5 ms, and the length of a subframe is 1.0 ms. A radio frame (or frame) 104 is a time-domain unit consisting of 10 subframes. In the frequency domain, the smallest unit for transmission is a subcarrier, and the total system transmission bandwidth consists of a total of NBW subcarriers 105. The basic unit of resources in the time-frequency domain is a resource element (RE) 106. REs can be represented by OFDM symbol indices and subcarrier indices. A resource block (RB, or physical resource block (PRB)) 107 consists of N in the time domain. symb A consecutive OFDM symbol 101 and a consecutive NRB subcarrier 108 in the frequency domain are defined. Therefore, an RB 107 is defined by N symb It consists of NRBs of REs, totaling 106. The smallest unit used for data transmission is an RB. In the LTE system, N... symb Set it to 7, set NRB to 12, and make NBW and NRB proportional to the bandwidth of the system transmission band.

[0051] In LTE systems, base stations transmit scheduling information for downlink or uplink data to terminals via downlink control information (DCI). Various DCI formats are defined. The DCI format to be used can be determined based on various parameters related to scheduling information for uplink data, scheduling information for downlink data, compact DCI with small size, spatial multiplexing using multiple antennas, and power control DCI. For example, DCI format 1 for downlink data scheduling information is configured to include at least the following control information.

[0052] - Resource Allocation Type 0 / 1 Flag: This indicates whether the resource allocation scheme is Type 0 or Type 1. Type 0 indicates resource allocation in units of RB groups (RBGs) using a bitmap. In LTE systems, the basic scheduling unit is an RB represented as a time-frequency domain resource. An RBG comprising multiple RBs is the basic scheduling unit for Type 0. Type 1 indicates the allocation of a specific RB within an RBG.

[0053] - Resource Block Allocation: This indicates the resource block (RB) allocated for data transmission. The resource represented by the RB allocation is determined based on system bandwidth and resource allocation scheme.

[0054] - Modulation and coding scheme (MCS): This refers to the modulation scheme applied to data transmission and the transport block (TB) size of the data to be transmitted.

[0055] - Hybrid Automatic Repeat Request (HARQ) process ID: This indicates the process ID of the corresponding HARQ process.

[0056] - New data indicator: This indicates whether HARQ is initiating a transmission or retransmission.

[0057] - Redundant version: This indicates a redundant version of HARQ.

[0058] - TPC (Transmission Power Control) commands for PUCCH: This indicates the TPC commands used for the Physical Uplink Control Channel (PUCCH) that acts as the uplink control channel.

[0059] DCI is channel-coded, modulated, and transmitted via PDCCH or EPDCCH.

[0060] Cyclic Redundancy Check (CRC) is appended to the DCI message payload, and the CRC is scrambled using a Radio Network Temporary Identifier (RNTI) corresponding to the terminal's identifier. Different RNTIs are used depending on the purpose of the DCI message, such as terminal-specific data transmission, power control commands, or random access responses. That is, the RNTI is not explicitly sent but is included in the CRC calculation used for transmission. Upon receiving a DCI message transmitted on the PDCCH, the terminal uses the assigned RNTI to check the CRC. If the CRC check is successful, the terminal knows that a DCI message has been sent to it.

[0061] The LTE system supports three types of resource allocation for PDSCH (Type 0, Type 1 and Type 2).

[0062] In resource allocation type 0, non-contiguous RB allocation in the frequency domain is supported, and bitmaps are used to indicate the allocated RBs. When the allocated RBs are indicated by a bitmap with the same size as the number of RBs, it may be necessary to send very large bitmaps for large cell bandwidths, resulting in high control signaling overhead. In resource allocation type 0, the bitmap size is reduced by grouping those RBs that are contiguous in the frequency domain and pointing to the group instead of the individual RBs. When the total transmission bandwidth is NRB and the number of RBs per RBG is P, the bitmap necessary for notifying RB allocation information in resource allocation type 0 becomes... If the number of RBs (i.e., P) in each RBG is small, scheduling flexibility increases, but control signaling overhead also increases. The value of P should be chosen appropriately to reduce the number of bits required while maintaining sufficient resource allocation flexibility. In LTE, the RBG size is determined by the downlink cell bandwidth, and possible RBG sizes are shown in Table 1 below.

[0063] Table 1

[0064]

[0065] In resource allocation type 1, resource allocation is performed by dividing the entire RBG set into subsets of RBGs distributed in the frequency domain. The number of subsets is given by the cell bandwidth, and the number of subsets in resource allocation type 1 is equal to the RBG size (P) in resource allocation type 0. The RB allocation information in resource allocation type 1 consists of the three fields described below.

[0066] - The first field indicates the selected subset of RBGs ( (bits).

[0067] - The second field indicates the shift (1 bit) of resource allocation in the subset.

[0068] - The third field indicates the bitmap of the assigned RBG ( (bits).

[0069] As a result, the total number of bits used in resource allocation type 1 becomes It equals the number of bits required in resource allocation type 0. Add a 1-bit indicator to notify the terminal whether the resource allocation type is 0 or 1.

[0070] Unlike the two resource allocation types mentioned above, resource allocation type 2 does not rely on a bitmap. Instead, resource allocation is indicated by the starting point and length of the RB allocation. Resource allocation types 0 and 1 support non-contiguous RB allocation, while resource allocation type 2 only supports sequential RB allocation. As a result, the RB allocation information in resource allocation type 2 consists of two fields as described below.

[0071] - The first field indicates the starting point of the RB (RBstart).

[0072] - The second field indicates the length (L) of consecutively allocated RBs. CRBs ).

[0073] In resource allocation type 2, the total One bit was used.

[0074] All three resource allocation types are associated with Virtual Resource Blocks (VRBs). In resource allocation types 0 and 1, VRBs are directly mapped to physical resource blocks in a local form. Resource allocation type 2 supports both local and distributed VRBs. In resource allocation type 2, there are additional indicators that specify whether a VRB is local or distributed.

[0075] Figure 2 This is a diagram of PDCCH 201 and enhanced PDCCH (EPDCCH) 202, which serve as downlink physical channels according to an embodiment, through which DCI is transmitted in LTE.

[0076] exist Figure 2 In this configuration, PDCCH 201 and PDSCH 203, which serves as the data transmission channel, are time-multiplexed and transmitted across the entire system bandwidth. The area of ​​PDCCH 201 is represented by the number of OFDM symbols, and the number of OFDM symbols is communicated to the terminal via a Control Format Indicator (CFI) transmitted through the Physical Control Format Indicator Channel (PCFICH). PDCCH 201 is assigned to the first OFDM symbol of a subframe to allow the terminal to decode the downlink scheduling assignment as quickly as possible. This reduces the decoding latency of the Downlink Shared Channel (DL-SCH), i.e., the total downlink transmission latency. Since one PDCCH carries one DCI message and multiple terminals can be scheduled simultaneously in the downlink and uplink, multiple PDCCHs are transmitted simultaneously in each cell. CRS (Cell-Specific Reference Signal) 204 is used as a reference signal for decoding PDCCH 201. CRS 204 is transmitted in each subframe across the entire bandwidth, and the scrambling and resource mapping are modified according to the cell ID. Since CRS204 is a reference signal shared by all terminals, terminal-specific beamforming cannot be used. In LTE, multi-antenna transmission for PDCCH is limited to open-loop transmit diversity. The number of CRS ports is implicitly communicated to the terminal from the decoding of the Physical Broadcast Channel (PBCH).

[0077] Resource allocation for PDCCH 201 is based on Control Channel Elements (CCEs), and a CCE consists of 9 Resource Element Groups (REGs) (i.e., 36 Resource Elements (REs)). Depending on the channel coding rate of the DCI message payload, the number of CCEs required for a particular PDCCH 201 can be 1, 2, 4, or 8. Different numbers of CCEs are used to implement link adaptation for PDCCH 201. The terminal should detect the signal without knowing any information about PDCCH 201. A search space indicating the set of CCEs used for blind decoding is specified in LTE. The search space consists of the set of CCEs for each aggregation level and is not explicitly notified by signaling but implicitly specified as a function of the terminal identifier and subframe number. The terminal performs PDCCH 201 decoding against all possible resource candidates generated from the CCEs in the search space set in each subframe and identifies information valid for the terminal through CRC checksum processing.

[0078] The search space is categorized into terminal-specific search space and common search space. Some or all terminals in a group can check the common search space of PDCCH 201 to receive control information common to the cell, such as dynamic scheduling and paging messages for system information. The scheduling and allocation information of DL-SCH for the transmission of System Information Block 1 (SIB-1), which includes cell operator information, can be received by checking the common search space of PDCCH 201.

[0079] exist Figure 2 In this configuration, EPDCCH 202 and PDSCH 203 are frequency-reused for transmission. The base station can appropriately allocate resources for EPDCCH 202 and PDSCH 203 through scheduling, efficiently supporting coexistence with data transmission from existing LTE terminals. However, since EPDCCH 202 is transmitted in the time domain over a complete subframe, there is a loss in transmission latency. Multiple EPDCCH 202s constitute an EPDCCH set, and the allocation of EPDCCH sets is performed on a PRB (Publication Resource Block) basis. The location information of the EPDCCH set is terminal-specific and is signaled via RRC (Radio Resource Control). Up to two EPDCCH sets can be configured for a terminal, and an EPDCCH set can be configured simultaneously for different terminals in a multiplexed manner.

[0080] EPDCCH 202 resource allocation is based on ECCE (Enhanced CCE). An ECCE can consist of four or eight Enhanced REGs (EREGs), and the number of EREGs per ECCE depends on the Cyclic Prefix (CP) length and subframe configuration information. An EREG consists of nine REs, and each PRB pair can have 16 EREGs. Depending on the RE mapping scheme of the EREGs, EPDCCH transmission can be local or distributed. The ECCE aggregation level can be 1, 2, 4, 8, 16, or 32, determined by the CP length, subframe configuration, EPDCCH format, and transmission scheme.

[0081] EPDCCH 202 only supports terminal-specific search spaces. Therefore, terminals that wish to receive system messages must check the common search space on the existing PDCCH 201.

[0082] In EPDCCH 202, the demodulation reference signal (DMRS) 205 is used as a reference signal for decoding. The precoding of EPDCCH 202 can be configured by the base station and uses terminal-specific beamforming. Through DMRS 205, the terminal can perform decoding on EPDCCH 202 without knowing what precoding was used. EPDCCH 202 uses the same DMRS pattern as PDSCH 203. However, unlike PDSCH 203, DMRS 205 in EPDCCH 202 can support transmission using up to four antenna ports. DMRS 205 is transmitted only in the corresponding PRB in which the EPDCCH is transmitted.

[0083] The port configuration information for DMRS 205 depends on the transmission scheme of EPDCCH 202. For local transmissions, the antenna port corresponding to the ECCE mapped to EPDCCH 202 is selected based on the terminal ID. If different terminals share the same ECCE (i.e., multi-user MIMO transmission is used), the DMRS antenna port can be assigned to each terminal. Alternatively, transmissions can be performed by sharing DMRS 205. The DMRS 205 can be distinguished based on the DMRS scrambling sequence set by higher-layer signaling. For distributed transmissions, up to two antenna ports are supported for DMRS 205, and a diversity scheme with precoder cyclic transmission is supported. DMRS 205 can be shared for all REs transmitted within a PRB.

[0084] In LTE, the entire PDCCH area consists of a logical set of CCEs and includes a search space comprised of the set of CCEs. The search space can be a common search space or a terminal-specific search space. The search space used for the LTE PDCCH is defined as follows.

[0085] The set of PDCCH candidates to be monitored is defined based on the search space, where the search space is at aggregation level L∈{1,2,4,8}. Defined by the set of PDCCH candidates. For each serving cell monitoring the PDCCH, the search space is... The CCE corresponding to the PDCCH candidate m is given by equation (1):

[0086]

[0087] Where Y k Defined as follows, i = 0, ..., L-1. For the common search space, m′ = m. For the PDCCH UE-specific search space, for the serving cell monitoring the PDCCH, if the UE being monitored is configured with a carrier indicator field, then m′ = m + N. (L) ·n CI , where n CI This is the carrier indicator field value; otherwise, if the monitored UE is not configured with a carrier indicator, then m′ = m, where m = 0, ..., M. (L) -1. M (L) It is the number of PDCCH candidates to be monitored in a given search space.

[0088] It should be noted that the carrier indicator field value is the same as the ServCellIndex (serving cell index).

[0089] For the public search space, for two aggregation levels L=4 and L=8, Y k It was set to 0.

[0090] For a specific search space of the UE at aggregation level L, variable Y k Defined by equation (2):

[0091] Y k =(A·Y k-1 )mod D......,(2)

[0092] Among them, Y -1 =n RNTI ≠0, A=39827, D=65537and ns is the time slot number within a radio frame.

[0093] For n RNTI The RNTI value is defined in Section 7.1 of the downlink and Section 8 of the uplink.

[0094] According to the definition of the search space used for PDCCH, the terminal-specific search space is implicitly defined as a function of the terminal identifier and subframe number, without being explicitly signaled. In other words, since the terminal-specific search space can change according to the subframe number, it can change over time, which solves the problem of a specific terminal being unable to use the search space due to other terminals (the blocking problem). Although a specific terminal cannot be scheduled in a given subframe (because all CCEs are used by all other terminals scheduled in the same subframe), this problem may not occur in the next subframe because the search space changes over time. For example, although the terminal-specific search spaces of terminal #1 and terminal #2 partially overlap in a certain subframe, the overlap in the next subframe can be expected to be different as the terminal-specific search space changes for each subframe.

[0095] Based on the definition of the search space used for PDCCH described above, the common search space is defined as a pre-agreed set of CCEs, because a certain group of terminals or all terminals must receive the PDCCH. The common search space does not vary based on terminal identifier or subframe number. The common search space is used to transmit various system messages, but it can also be used to transmit control information for specific terminals. Thus, the common search space can be a solution to the problem of being unable to schedule terminals due to a lack of available resources in a terminal-specific search space.

[0096] The search space for a given aggregation level is the set of candidate control channels consisting of CCEs that the terminal should attempt to decode. Since there are several aggregation levels that create a group with 1, 2, 4, and 8 CCEs, the terminal has multiple search spaces. The number of PDCCH candidates that the terminal will monitor in the search space for a given aggregation level in the LTE PDCCH is defined as shown in Table 2 below.

[0097] Table 2

[0098]

[0099] According to Table 2, for the terminal-specific search space, {6, 6, 2, 2} PDCCH candidates are used to support aggregation levels {1, 2, 4, 8} respectively. For the common search space, {4, 2} PDCCH candidates are used to support aggregation levels {4, 8} respectively. The reason for supporting only aggregation levels {4, 8} in the common search space is to improve coverage characteristics, since system messages typically must reach the cell edge.

[0100] DCI transmitted via the common search space is defined only for certain DCI formats (such as 0 / 1A / 3 / 3A / 1C), which are used for system messages or power control for terminal groups. DCI formats with spatial multiplexing are not supported in the common search space. The downlink DCI format to be decoded in the terminal-specific search space varies depending on the transmission mode set for the corresponding terminal. Since the transmission mode is set via RRC signaling, the exact subframe number is not specified regarding whether the setting is valid for the terminal. Regardless of the transmission mode, the terminal can operate by always decoding DCI format 1A to avoid lost communication.

[0101] The above has provided a description of transmitting downlink control channels and search space in existing LTE or LTE-A systems.

[0102] Next, a description of the downlink control channel in a 5G communication system will be given.

[0103] Figure 3 This is a diagram illustrating the time-frequency resources of a downlink control channel that can be used in a 5G communication system according to an embodiment. Figure 3 In this design, the basic unit of time-frequency resources constituting the control channel (REG 303, or New Radio (NR) REG (NR-REG 303)) consists of one OFDM symbol 301 in the time domain and 12 subcarriers 302 (i.e., 1RB) in the frequency domain. By assuming the time domain unit is one OFDM symbol 301 within the basic unit of the control channel, time multiplexing of the data and control channels can be performed within a subframe. Placing the control channel before the data channel reduces user processing time, thus helping to meet latency requirements. By setting the frequency domain unit of the control channel to 1RB (302), frequency multiplexing between the control and data channels can be performed more efficiently.

[0104] Through connection Figure 3 The NR-REG 303 shown can be configured with control channel regions of various sizes. When the basic unit for allocating downlink control channels in a 5G system is the NR-CCE 304, one NR-CCE 304 can be composed of many NR-REG 303s. Figure 3The NR-REG 303 shown can consist of 12 REs, and if an NR-CCE 304 consists of 4 NR-REG 303s, then an NR-CCE 304 can consist of 48 REs. When a downlink control area is configured, the downlink control area can consist of many NR-CCE 304s, and a specific downlink control channel can be mapped to one or more NR-CCE 304s within the control area for transmission according to the aggregation level. The NR-CCE 304s in the control area are identified by their numbers, and these numbers can be assigned according to a logical mapping scheme.

[0105] Figure 3 The basic unit of the downlink control channel shown (i.e., NR-REG 303) may include the RE to which the DCI is mapped and the area to which the DMRS 305, acting as a reference signal for decoding the DCI, is mapped. Considering the overhead due to RS dispatch, the DMRS 305 can be transmitted efficiently. When the downlink control channel is mapped to multiple OFDM symbols for transmission, the DMRS 305 may be mapped to only the first OFDM symbol for transmission. The number of antenna ports used to transmit the downlink control channel can be taken into account when mapping the DMRS 305. Figure 3 In this embodiment, two antenna ports are used, but this disclosure is not limited to this. There can be a DMRS 306 transmitted for antenna port #0 and a DMRS 307 transmitted for antenna port #1. DMRS for different antenna ports can be multiplexed in various ways. Figure 3 In this process, DMRS corresponding to different antenna ports is transmitted orthogonally via different REs. DMRS can be transmitted using frequency division multiplexing (FDM) or code division multiplexing (CDM). Various other DMRS modes can exist in relation to the number of antenna ports. In the following description of the embodiment, it is assumed that two antenna ports are used. The same principle can be applied to cases using two or more antenna ports.

[0106] Figure 4 This is a diagram of a control region (control resource set (CORESET)) in a 5G wireless communication system according to an embodiment, where a downlink control channel is transmitted.

[0107] exist Figure 4 In the frequency domain, there is a system bandwidth of 410, and in the time domain, there are time slots of 420 (assuming one time slot includes 7 OFDM symbols). The entire system bandwidth 410 can be composed of multiple bandwidth components (e.g., Figure 4The four bandwidth components are composed of bandwidth component #1 (402), bandwidth component #2 (403), bandwidth component #3 (404), and bandwidth component #4 (405).

[0108] exist Figure 4 In the system, two control regions (control region #1 (440) and control region #2 (450)) are configured. In the frequency domain, control regions 440 and 450 can be set on specific sub-bands within the entire system bandwidth 410. Control region #1 (440) is configured on bandwidth portion #1 (402) and bandwidth portion #2 (403), and control region #2 (450) is configured within bandwidth portion #4 (405). In the time domain, a control region may include one or more OFDM symbols, and the number of such OFDM symbols may be referred to as the control region length (control resource set duration 460 or 470). Figure 4 In the configuration, control region #1 (440) is configured to have a control region length #1 with 2 symbols, and control region #2 (470) is configured to have a control region length #2 with 1 symbol.

[0109] In 5G communication systems, from the base station's perspective, multiple control regions can be configured within a single system. Similarly, from the terminal's perspective, multiple control regions can be configured for a single terminal. A terminal can be assigned to some of the control regions configured within the system. Therefore, a terminal may not be aware of the specific control regions existing within the system. Figure 4 In the system, two control regions (control region #1 (440) and control region #2 (450)) are configured, and control region #1 (440) can be assigned to terminal #1, and control region #1 (440) and control region #2 (450) can be assigned to terminal #2. Without an additional indicator, terminal #1 may not be aware of the existence of control region #2 (450).

[0110] The control area in the aforementioned 5G system can be configured as a common control area, a terminal group common control area, or a terminal-specific control area. The control area can be configured for a terminal via terminal-specific signaling, terminal group common signaling, or RRC signaling. Configuring a control area for a terminal means providing information related to the control area's location, subband, resource allocation, and length. The base station can provide the following information.

[0111] Table 3

[0112]

[0113] In addition to the above configuration information, other information necessary for the terminal to send downlink control channels can be configured.

[0114] In 5G communication systems, it is necessary to flexibly define and operate the frame structure by taking into account various services and requirements. For example, depending on the requirements of each service, each service may have different subcarrier spacings. Currently, two schemes are being considered to support multiple subcarriers in 5G communication systems. As the first scheme for supporting multiple subcarriers in 5G communication systems, the set of subcarrier spacings that a 5G communication system can have can be determined using the following equation (3).

[0115] Δf=f02 m ...............(3)

[0116] Here, f0 represents the basic subcarrier spacing of the system, and m represents an integer scaling factor. If f0 is 15 kHz, the set of subcarrier spacings that a 5G communication system can have may include 7.5 kHz, 15 kHz, 30 kHz, 60 kHz, 120 kHz, etc. The system can be configured by using all or some elements of the subcarrier spacing set given by equation (3). Assume that, according to the above scheme, a subcarrier spacing set {15 kHz, 30 kHz, 60 kHz} with f0 = 15 kHz is used in the 5G communication system. However, the technique proposed in this paper can be applied without restriction to cases with different subcarrier spacing sets (e.g., {17.5 kHz, 35 kHz, 70 kHz} with f0 = 17.5 kHz). If we consider the subcarrier spacing set {17.5 kHz, 35 kHz, 70 kHz}, this subcarrier spacing set can be mapped for a description based on f0 = 15 kHz. Similarly, subcarrier spacing sets based on 35kHz, 70kHz, or 140kHz can be mapped to other subcarrier spacing sets based on 30kHz, 60kHz, or 120kHz, respectively.

[0117] Figure 5 Resource elements 500 are shown for subcarrier spacings △f1 (501), △f2 (502), and △f3 (503), respectively. The subcarrier spacings △f1 (501), △f2 (502), and △f3 (503) correspond to 15 kHz, 30 kHz, and 60 kHz, respectively. Each resource element has a T... s (504), T s '(505) or T s The OFDM symbol length is (506). As a characteristic of OFDM symbols, the subcarrier spacing and OFDM symbol length have an inverse relationship, and it can be confirmed that the symbol length shortens as the subcarrier spacing increases. That is, T... s The value of (504) is T. s It is twice the value of '(505)' and is T. s Four times the value of (506).

[0118] Figure 6 This is a diagram illustrating the bandwidth portion considered in 5G communication according to an embodiment.

[0119] A base station can configure one or more bandwidth portions for a terminal. Figure 6 In this configuration, two bandwidth portions (i.e., bandwidth portion #1 (610) and bandwidth portion #2 (611)) are configured in terminal bandwidth 601.

[0120] The base station can specify the location and bandwidth size of each bandwidth segment for the terminal. Figure 6 In the configuration, bandwidth portion #1 (610) is located at center frequency #1 (604) and has a bandwidth size of bandwidth #1 (602), while bandwidth portion #2 (611) is located at center frequency #2 (605) and has a bandwidth size of bandwidth #2 (603). The location of the bandwidth portions can be set in various ways, for example, by informing the offset of a reference point within the terminal bandwidth or system bandwidth. The size of the bandwidth portions can be set in various ways, for example, by informing the number of RBs present in the bandwidth portions.

[0121] The base station can configure a set of parameters (e.g., subcarrier spacing) for each bandwidth portion for the terminal. Figure 6 In this configuration, the subcarrier spacing of bandwidth portion #1 (610) is set to Δf1 (=15kHz, 608), and the subcarrier spacing of bandwidth portion #2 (611) is set to Δf2 (=30kHz, 609). The time slot duration of the bandwidth portion can be changed according to the subcarrier spacing. The time slot duration can be changed not only by the subcarrier spacing but also by the number of OFDM symbols constituting the time slot. A time slot can consist of 7 OFDM symbols or 14 OFDM symbols. The base station can set information about the time slot duration of each bandwidth portion (i.e., information about the number of OFDM symbols constituting the time slot (7 OFDM symbols or 14 OFDM symbols)). Bandwidth portion #1 (610) is configured to have a time slot duration #1 (=7 OFDM symbols, 606), and bandwidth portion #2 (611) is configured to have a time slot duration #2 (=14 OFDM symbols, 607).

[0122] A base station can configure control regions (control resource sets) for the downlink control channel to transmit and receive DCIs for each bandwidth portion of the terminal. The base station can configure control region #1 (612) as the control region for transmitting DCIs for bandwidth portion #1 (610), and can configure control region #2 (613) as the control region for transmitting DCIs for bandwidth portion #2 (611). To receive DCIs for a specific bandwidth portion, the terminal can check the corresponding control region set within that bandwidth portion. To configure the control region for a bandwidth portion, the base station can, for example, notify the terminal of all or some of the system parameters listed in Table 3.

[0123] The base station can send terminal configuration information for the bandwidth portion via higher-layer signaling (e.g., RRC signaling).

[0124] As mentioned earlier, to achieve ultra-high-speed data services of several Gbps in 5G systems, signals can be transmitted and received with ultra-wide bandwidths ranging from tens to hundreds of MHz or several GHz. The bandwidth that a terminal can support may differ from the system bandwidth. Specific bandwidth portions can be configured for the terminal to support signal transmission and reception.

[0125] To schedule data to be sent to a terminal, a base station can determine the bandwidth portion to be used for transmission and send different DCIs based on the configuration information of said bandwidth portion. More specifically, the base station can configure one or more bandwidth portions for the terminal and can send signals using one or more of the configured bandwidth portions. Depending on various system parameters set for said bandwidth portion (such as bandwidth size, slot duration, and subcarrier spacing), the scheduling information for data to be sent via each bandwidth portion can be different. Therefore, one or more different DCIs can be sent.

[0126] According to this disclosure, a DCI transmission method can be provided for efficient system operation in various signal transmission and reception operations using bandwidth portions. A base station can transmit DCI to a terminal for data transmission via the same bandwidth portion. A base station can transmit DCI to a terminal for data transmission via different bandwidth portions. A base station can transmit DCI to a terminal for data transmission via multiple bandwidth portions. To support the above operations, additional DCI fields may be required, or different interpretations of the same DCI field may be necessary.

[0127] Example 1

[0128] The first embodiment of this disclosure provides a method and apparatus for transmitting and receiving DCI.

[0129] A base station can configure one or more bandwidth portions for a terminal. Each bandwidth portion can be configured with different system parameters, such as subcarrier spacing, bandwidth size, RBG size, and slot duration.

[0130] The base station can send an indicator to the terminal for activating or deactivating one or more bandwidth portions of the configuration, and the base station and the terminal can transmit and receive signals via the activated bandwidth portion. The base station can notify the terminal of this indicator via higher-layer signaling (e.g., RRC signaling or Media Access Control (MAC) Control Element (CE) signaling) or L1 signaling (e.g., common DCI, group common DCI, or terminal-specific DCI).

[0131] The base station can configure a control region (control resource set) for the downlink control channel in each bandwidth portion configured for the terminal, and can transmit the DCI for the bandwidth portion via the corresponding control region.

[0132] More specifically, see reference Figure 6 The base station can configure bandwidth portion #1 (602) and bandwidth portion #2 (603) for the terminal, and can configure control area #1 (612) and control area #2 (613) for bandwidth portion #1 (602) and bandwidth portion #2 (603) respectively. The base station can transmit DCI for bandwidth portion #1 (602) via control area #1 (612), and can transmit DCI for bandwidth portion #2 (603) via control area #2 (613).

[0133] The terminal can receive configuration information for one or more bandwidth portions from the base station. The terminal can also receive configuration information for the control area associated with each bandwidth portion from the base station. Furthermore, the terminal can receive indicators from the base station for activating or deactivating one or more of the configured bandwidth portions. The terminal can receive DCI for the corresponding bandwidth portion via the control area associated with one or more activated bandwidth portions.

[0134] Example 2

[0135] A second embodiment of this disclosure provides a method and apparatus for transmitting and receiving DCI.

[0136] A base station can configure one or more bandwidth portions for a terminal.

[0137] The base station can send an indicator to the terminal for activating or deactivating one or more of the bandwidth portions of the configuration, and the base station and the terminal can transmit and receive signals via the activated bandwidth portion.

[0138] The base station can configure a control region (control resource set) for the downlink control channel in each bandwidth portion configured for the terminal, and can transmit the DCI for the bandwidth portion via the corresponding control region.

[0139] The base station can also transmit DCI for one or more different bandwidth portions via control areas of one or more active bandwidth portions. The base station can configure the terminal using information about the bandwidth portion via higher-layer signaling such as RRC or MAC CE signaling, the control area of ​​which will be used to transmit DCI for other bandwidth portions.

[0140] The terminal can receive configuration information from the base station for one or more bandwidth portions. The terminal can receive configuration information from the base station for a control area associated with each bandwidth portion. The terminal can receive configuration information for a control area of ​​a specific bandwidth portion, which will be used to receive DCI for other bandwidth portions. The terminal can receive indicators from the base station for activating or deactivating one or more configured bandwidth portions. The terminal can receive DCI for the corresponding bandwidth portion or other bandwidth portions via a control area associated with one or more activated bandwidth portions.

[0141] More specifically, reference Figure 6 The base station can configure bandwidth portion #1 (602) and bandwidth portion #2 (603) for the terminal, and can configure control area #1 (612) and control area #2 (613) for bandwidth portion #1 (602) and bandwidth portion #2 (603) respectively.

[0142] The base station can configure configuration information for the terminal, which instructs the transmission of DCI for bandwidth portion #1 (602) via control area #1 (612) and DCI for bandwidth portion #2 (603) via control area #2 (613), and can perform DCI transmission according to the configuration information. Based on the configuration information from the base station, the terminal can monitor control area #1 (612) to receive DCI for bandwidth portion #1 (602) and monitor control area #2 (613) to receive DCI for bandwidth portion #2 (603).

[0143] The base station can also configure configuration information for the terminal, the configuration information indicating that DCIs for bandwidth portions #1 (602) and #2 (603) are transmitted via control area #1 (612), and DCI transmission can be performed according to the configuration information. Based on the configuration information from the base station, the terminal can monitor control area #1 (612) to receive DCIs for bandwidth portions #1 (602) and DCIs for bandwidth portions #2 (603).

[0144] The base station can also configure configuration information for the terminal, the configuration information indicating that DCIs for bandwidth portions #1 (602) and #2 (603) are transmitted via control area #2 (613), and DCI transmission can be performed according to the configuration information. Based on the configuration information from the base station, the terminal can monitor control area #2 (613) to receive DCIs for bandwidth portions #1 (602) and DCIs for bandwidth portions #2 (603).

[0145] For the purpose of describing embodiments of this disclosure, the following terms will be defined.

[0146] - Self scheduling: This indicates that the DCI indicating data scheduling and the scheduled data are transmitted via the same bandwidth portion. The base station can transmit data and the corresponding DCI using the same bandwidth portion, and the terminal can obtain data scheduling information for a specific bandwidth portion from the DCI transmitted via the same bandwidth portion.

[0147] - Cross scheduling: This refers to the DCI indicating data scheduling and the scheduled data being transmitted via different bandwidth sections. The base station can transmit data and the corresponding DCI using different bandwidth sections, and the terminal can obtain data scheduling information for a specific bandwidth section from the DCI transmitted via other bandwidth sections.

[0148] Base stations can configure self-bandwidth partial scheduling or cross-bandwidth partial scheduling for terminals via higher-level signaling such as RRC signaling.

[0149] Example 3

[0150] The third embodiment of this disclosure provides a DCI design scheme that reduces the number of blind decodes performed by the terminal when the control area of ​​a specific bandwidth portion is used not only to transmit the corresponding DCI but also to transmit DCI for other bandwidth portions.

[0151] As described in the second embodiment, the base station can notify the terminal whether a specific bandwidth portion is self-scheduled or cross-scheduled. For example, in Figure 6 In this configuration, the base station can specify configuration information indicating that both DCI#1, containing scheduling information for bandwidth section #1 (602), and DCI#2, containing scheduling information for bandwidth section #2 (603), are transmitted via control area #1 (612) of bandwidth section #1 (602). Self-scheduling is performed for bandwidth section #1 (602), and cross-scheduling is performed for bandwidth section #2 (603).

[0152] Since bandwidth section #1 (602) and bandwidth section #2 (603) can be set by different system parameters, the DCIs (DCI#1 and DCI#2) used for each bandwidth section can have different sizes.

[0153] Different bandwidth segments can have different bandwidth sizes and different subcarrier spacings, and therefore can have different numbers of RBs or RBGs of different sizes. The DCI for each bandwidth segment can contain data scheduling information (frequency domain resource allocation information, i.e., RB allocation) for the corresponding bandwidth segment. For different bandwidth segments set with different parameters (bandwidth, subcarrier spacing, number of RBs, and RBG size), the number of bits required for RB allocation may vary, and therefore the total DCI size may vary.

[0154] Different bandwidth portions can have different subcarrier spacings and different numbers of OFDM symbols per slot, and therefore can have different slot durations. The DCI for each bandwidth portion can contain data scheduling information (i.e., time-domain resource allocation information) for the corresponding bandwidth portion.

[0155] Time-domain resource allocation information can be represented by the following: the index of the first OFDM symbol at the start of data transmission (start point), the index of the last OFDM symbol at the end of data transmission (end point), the total number of OFDM symbols used for data transmission (data length), the time slot index at the point where data transmission is performed, or the total number of time slots used for data transmission, or a combination of the foregoing. The number of bits required for time-domain resource allocation of data may vary for different bandwidth portions set by different parameters affecting time-domain resource allocation (such as different subcarrier spacing, different number of OFDM symbols per time slot, and different time slot durations), and therefore, the total DCI size may vary.

[0156] Therefore, when the terminal checks control area #1 (612) to detect DCI#1 and DCI#2, the number of blind decodes may increase because the terminal should perform blind decoding by assuming the size of DCI#1 and DCI#2.

[0157] In a third embodiment of this disclosure, the DCIs used for different bandwidth portions are set to have the same size. Due to the different DCI sizes, the terminal does not need to perform additional blind decoding. The terminal may be able to reduce the number of blind decodes, thereby effectively reducing power consumption.

[0158] Example 3-1

[0159] The size of the DCI used for the bandwidth portion can be equal to the size of the maximum DCI. Here, zero bits (bits filled with zeros) can be appended to the smaller DCI to give it the same size as the relatively larger DCI.

[0160] More specifically, see reference Figure 6 When the size of DCI#1 used for bandwidth section #1 (602) is M bits and the size of DCI#2 used for bandwidth section #2 (603) is N bits, if M is greater than N, (MN) zero bits can be appended to DCI#2 so that DCI#2 has the same size as DCI#1.

[0161] To send DCI#1, the base station can directly send M bits of DCI#1 to the terminal. To send DCI#2, the base station can generate N bits of DCI#2, fill DCI#2 with (MN) zero bits, and send M bits of DCI#2 to the terminal.

[0162] When the terminal monitors control area #1 (612) for DCI#1 and DCI#2, it can perform blind decoding by assuming the DCI size is M bits (i.e., the size of DCI#1 with a larger size). Upon obtaining DCI#1 after blind decoding, the terminal can directly receive DCI#1 as control information. Upon obtaining DCI#2 after blind decoding, the terminal can assume that (MN) zero bits are padded and extract N bits of valid information from DCI#2.

[0163] Example 3-2

[0164] The base station can specify the size of the DCI to be monitored by the terminal in the control area. The base station can transmit this information to the terminal via higher-layer signaling such as RRC signaling or MAC CE signaling. If the actual DCI size and the specified DCI size are different, the DCI size can be adjusted in different ways. For example, if the actual DCI size is smaller than the specified DCI size, zero bits can be appended to the corresponding DCI before transmission to give it the specified DCI size. If the actual DCI size is larger than the specified DCI size, some bits of the corresponding DCI may not be transmitted. Some bits indicating frequency domain resource allocation may not be transmitted (DCI shortening or DCI truncation). When M bits are used as a bitmap indicator for frequency domain resource allocation, and if it is necessary to shorten the DCI by N bits according to the specified DCI size, only (MN) bits can be used for the resource allocation field. DCI shortening can be performed in various other ways.

[0165] The terminal can perform blind decoding in the configured control area by assuming the DCI size notified from the base station.

[0166] More specifically, reference Figure 6 Assume that the size of DCI#1 used for bandwidth section #1 (602) is M bits, the size of DCI#2 used for bandwidth section #2 (603) is N bits, and the base station sets the size of the DCI to be monitored to L bits. The values ​​of M, N, and L can be equal to or different from each other. If L > M, then (LM) zero bits can be appended to DCI#1 before transmission to give it a size of L bits. If L < N, then one or more fields of DCI#2 can be shortened before transmission to give it a size of L bits. The DCI fields to be shortened and the number of bits to be discarded can be specified in advance or set via higher-layer signaling.

[0167] Example 3-3

[0168] Specific fields of different DCIs used for different bandwidth portions can be designed to have the same size. Within the fields of the DCI, the time-domain resource allocation indicator and the frequency-domain resource allocation indicator can have different sizes depending on the configuration information of the corresponding bandwidth portion.

[0169] Example 3-3-1

[0170] In different DCIs used for different bandwidth portions, the fields used for time-domain resource allocation information can be made to have the same size. More specifically, the following scheme can be applied.

[0171] Option 1

[0172] To ensure that the time-domain resource allocation fields for DCIs used in different bandwidth sections have the same size, the size of the time-domain resource allocation field can be equal to the larger field size. When the size of the time-domain resource allocation field for DCI#1 used in bandwidth section #1 is M bits and the size of the time-domain resource allocation field for DCI#2 used in bandwidth section #2 is N bits, if M>N, it can be assumed that the size of the time-domain resource allocation field for DCI#2 is N, and (MN) zero bits can be appended to the time-domain resource allocation field of DCI#2.

[0173] Option 2

[0174] To ensure that the time-domain resource allocation field for DCIs used in different bandwidth sections has the same size, the size of the time-domain resource allocation field can be equal to the smaller field size. When the size of the time-domain resource allocation field for DCI#1 used in bandwidth section #1 is M bits and the size of the time-domain resource allocation field for DCI#2 used in bandwidth section #2 is N bits, if M > N, then it can be assumed that the size of the time-domain resource allocation field for DCI#1 is M. The time-domain resource allocation field for DCI#2 can be interpreted in the conventional way without changing the size.

[0175] The time-domain resource allocation field of DCI#1, whose size is reduced from M bits to N bits, can be interpreted differently from the conventional time-domain resource allocation field. For example, assuming the slot duration of bandwidth section #1 is 14 OFDM symbols, DCI#1 can use 4 bits to indicate the start of the corresponding data, and assuming the slot duration of bandwidth section #2 is 7 OFDM symbols, DCI#2 can use 3 bits to indicate the start of the corresponding data. It can be assumed that the time-domain resource allocation field of DCI#1 is 3 bits, and the start of the data corresponding to the 14 symbols can be remapped via a 3-bit indicator. For example, a 3-bit indicator can be used to indicate either an even index {2, 4, 6, 8, 10, 12, 14} or an odd index {1, 3, 5, 7, 9, 11} among the 14 symbol indices.

[0176] The interpretation of temporal resource allocations related to modified DCI fields can be pre-specified through system parameters. Alternatively, the base station can redefine information regarding the mapping between the corresponding indicators and temporal resource allocations and notify the terminal via higher-layer signaling.

[0177] For different DCIs of the same size, the terminal can identify the bandwidth portion associated with a specific DCI and can interpret the same DCI information differently. When a DCI obtained through blind decoding is associated with bandwidth portion #1, a first analysis scheme (i.e., the mapping between DCI indicators and time-domain resource allocation information) can be applied to the time-domain resource allocation field of the DCI. And when a DCI obtained through blind decoding is associated with bandwidth portion #2, a second analysis scheme (i.e., the mapping between DCI indicators and time-domain resource allocation information) can be applied to the time-domain resource allocation field of the DCI. The interpretation of the time-domain resource allocation of a DCI with modified fields (i.e., configuration information regarding the first and second analysis schemes) can be pre-specified through system parameters or notified to the terminal by the base station via configuration information.

[0178] Example 3-3-2

[0179] In different DCIs used for different bandwidth portions, the fields used for frequency domain resource allocation information can be made to have the same size. More specifically, the following scheme can be applied.

[0180] Option 1

[0181] For different bandwidth segments, if the bandwidth segments have the same size but different subcarrier spacings, the DCI field used for frequency domain resource allocation information can have the same size by scaling the RBG size according to the subcarrier spacing. More specifically, suppose for bandwidth segment #1, the subcarrier spacing is Δf1 and the RBG size is M, while for bandwidth segment #2, the subcarrier spacing is Δf2 and the RBG size is N. If Δf2 = Δf1 * 2 n Then, according to N = M / 2 n Perform scaling.

[0182] For example, assuming both bandwidth section #1 and bandwidth section #2 have a bandwidth size of 10MHz, bandwidth section #1 has a subcarrier spacing of 15kHz, and bandwidth section #2 has a subcarrier spacing of 30kHz, then the number of RBs used for bandwidth section #1 may be twice the number of RBs used for bandwidth section #2. When the RBG size used for bandwidth section #1 is M, the RBG size used for bandwidth section #2 can be set to M / 2, so that the number of bits required for frequency domain resource allocation for bandwidth section #1 is equal to the number of bits required for frequency domain resource allocation for bandwidth section #2.

[0183] When performing data scheduling for each bandwidth segment, the base station can assume the RBG size given by Scheme 1 above, and determine the frequency domain resource allocation information for the corresponding DCI based on the assumed RBG size. The terminal can obtain the DCI information for each bandwidth segment by assuming the RBG size given by Scheme 1 above.

[0184] Option 2

[0185] If different bandwidth segments have the same number of RBs, then the same RBG size can be assumed. If both bandwidth segment #1 and bandwidth segment #2 consist of M RBs, then the RBG size for bandwidth segment #1 and bandwidth segment #2 can be assumed to be N.

[0186] When performing data scheduling for each bandwidth segment, the base station can assume the RBG size given by Scheme 2 above, and determine the frequency domain resource allocation information for the corresponding DCI based on the assumed RBG size. The terminal can obtain the DCI information for each bandwidth segment by assuming the RBG size given by Scheme 2 above.

[0187] Option 3

[0188] To ensure that the time-domain resource allocation field of the DCI used for different bandwidth portions has the same size, the base station can notify the terminal of the RBG size for each bandwidth portion. This can be achieved via higher-layer signaling such as RRC signaling or MAC CE signaling. For each bandwidth portion, the terminal can determine the size of the field used for frequency-domain resource allocation information in the DCI based on the RBG size notified by the base station, determine the total DCI size, and obtain the corresponding DCI through blind decoding.

[0189] Option 4

[0190] To ensure that the time-domain resource allocation fields for DCIs used in different bandwidth sections have the same size, the size of the frequency-domain resource allocation field can be equal to the larger field size. More specifically, when the size of the frequency-domain resource allocation field for DCI#1 used in bandwidth section #1 is M bits, and the size of the frequency-domain resource allocation field for DCI#2 used in bandwidth section #2 is N bits, and if M > N, it can be assumed that the size of the frequency-domain resource allocation field for DCI#2 is N, and (MN) zero bits can be appended to the frequency-domain resource allocation field of DCI#2.

[0191] For each bandwidth segment, the base station can determine the size of the frequency domain resource allocation field in the DCI using Scheme 4 described above. For each bandwidth segment, the terminal can assume the size of the frequency domain resource allocation field in the DCI given by Scheme 4 described above and perform blind decoding on the DCI.

[0192] Option 5

[0193] To ensure that the time-domain resource allocation fields for DCIs used in different bandwidth sections have the same size, the size of the frequency-domain resource allocation field can be equal to the smaller field size. More specifically, when the size of the frequency-domain resource allocation field for DCI#1 used in bandwidth section #1 is M bits, and the size of the frequency-domain resource allocation field for DCI#2 used in bandwidth section #2 is N bits, and if M > N, then it can be assumed that the size of the frequency-domain resource allocation field for DCI#1 is M.

[0194] The frequency domain resource allocation field of DCI#2, whose size has not been changed, can be interpreted in a conventional manner. The frequency domain resource allocation field of DCI#1, whose size has been reduced from M bits to N bits, can be interpreted differently from the conventional frequency domain resource allocation field. How to interpret the frequency domain resource allocation related to the changed DCI field can be pre-specified through system parameters. Alternatively, the base station can redefine information regarding the mapping between the corresponding indicators and the frequency domain resource allocation and notify the terminal via higher-layer signaling.

[0195] For different DCIs of the same size, the terminal can identify the bandwidth portion associated with a specific DCI and can interpret the same DCI information differently. When a DCI obtained through blind decoding is associated with bandwidth portion #1, a first analysis scheme (i.e., the mapping between DCI indicators and frequency domain resource allocation information) can be applied to the frequency domain resource allocation field of the DCI. Similarly, when a DCI obtained through blind decoding is associated with bandwidth portion #2, a second analysis scheme (i.e., the mapping between DCI indicators and frequency domain resource allocation information) can be applied to the frequency domain resource allocation field of the DCI. The interpretation of the time domain resource allocation for a DCI with modified fields (i.e., configuration information regarding the first and second analysis schemes) can be pre-specified through system parameters or notified to the terminal by the base station via configuration information.

[0196] Example 3-3-3

[0197] In DCIs used for different bandwidth portions, fields corresponding to the overall resource allocation information can have the same total size (i.e., the sum of the sizes of the time-domain resource allocation field and the frequency-domain resource allocation field). More specifically, for bandwidth portion #1, assume the size of the time-domain resource allocation field is M1 bits, and the size of the frequency-domain resource allocation field is N1 bits, and for bandwidth portion #2, assume the size of the time-domain resource allocation field is M2 bits, and the size of the frequency-domain resource allocation field is N2 bits. The sizes of the above fields can be adjusted to satisfy the following equation (4).

[0198] M1+N1=M2+N2............(4)

[0199] The total size of the field corresponding to the overall resource allocation information can be pre-specified, determined based on a larger field size for a specific bandwidth portion, or determined based on a smaller field size for a specific bandwidth portion. This size information can be communicated to the terminal by the base station via higher-layer signaling such as RRC signaling or MAC CE signaling.

[0200] For each bandwidth segment, the terminal can assume the total size of the resource allocation field determined based on the above scheme and obtain the corresponding DCI.

[0201] Example 4

[0202] In a fourth embodiment of this disclosure, additional fields are provided in the DCI exchanged between the base station and the terminal.

[0203] Base stations and terminals can transmit and receive data using one or more carriers (or component carriers). For each carrier, one or more bandwidth portions can be configured to enable the base station and terminal to transmit and receive data. The base station can inform the terminal of information about the carriers to be used for data transmission and reception via higher-layer signaling (e.g., RRC signaling or MAC CE signaling). The base station can also inform the terminal of configuration information about the bandwidth portions in each carrier via higher-layer signaling (e.g., RRC signaling or MAC CE signaling). The base station and terminal can transmit and receive data using the bandwidth portions configured on the carriers.

[0204] DCI for a specific carrier can be transmitted or received via the same carrier (self-scheduled) or via other carriers (cross-scheduled). The base station can notify the terminal of the configuration of the carriers through which it will transmit DCI for a specific carrier via higher-layer signaling (e.g., RRC signaling or MAC CE signaling).

[0205] As described above, the base station and the terminal can transmit and receive data via one or more carriers. The base station and the terminal can transmit and receive data via one or more bandwidth portions of each carrier. In the fourth embodiment, the DCI exchanged between the base station and the terminal may further include the following fields.

[0206] Option 1

[0207] - Carrier Indicator: Indicates the carrier corresponding to the received DCI and can consist of N bits. This can be used to notify the terminal of up to 2 N One of the carrier indices.

[0208] - Bandwidth Part Indicator: Indicates the bandwidth portion corresponding to the received DCI and can consist of M bits. This can be used to notify the terminal of up to 2 M One of the bandwidth portion indexes.

[0209] Regarding Option 1 above, the value of N corresponding to the number of carrier indicator bits can be fixed as a system parameter. Alternatively, the base station can determine the value of N as the number of bits used for the carrier indicator. The base station can notify the terminal of the value of N via higher-layer signaling (e.g., RRC signaling or MAC CE signaling).

[0210] Regarding option 1 above, the carrier indicated by the carrier indicator can be pre-specified. More specifically, assuming there are C carriers and N bits used as carrier indicators, the base station can select 2 carriers from the C carriers. N One carrier, and use an N-bit indicator to map the selected 2 NThere are 2 carriers. For example, assuming there are C (e.g., 8) carriers {C1, C2, C3, C4, C5, C6, C7, C8} and N (=2) bits used as carrier indicators, the base station can select 2 carriers from the 8 carriers. N =4 carriers (e.g., {C1, C2, C4, C7}), and the four selected carriers are mapped using carrier indicator values ​​{00, 01, 10, 11}. Table 4 illustrates this mapping.

[0211] Table 4

[0212] Carrier indicator Carrier Index 00 C1 01 C2 10 C4 11 C7

[0213] If C < 2 N Then you can keep 2 N Some of the carrier indicator values. For example, assuming there are C (e.g., 3) carriers {C1, C2, C3} and N (=2) bits used as carrier indicators, the base station can reserve one of four carrier indicator values. Mapping can be performed as shown in Table 5.

[0214] Table 5

[0215] Carrier indicator Carrier Index 00 C1 01 C2 10 C3 11 reserve

[0216] The base station can notify the terminal of the above information (the index of the carrier to be used and the corresponding carrier indicator) through higher-layer signaling (e.g., RRC signaling).

[0217] The terminal can receive configuration information about carrier indicators from the base station, interpret the received carrier indicators based on the configuration information, and determine the carrier corresponding to the received DCI.

[0218] Regarding Option 1 above, the value of M corresponding to the number of bits for the bandwidth portion indicator can be fixed as a system parameter. Alternatively, the base station can determine the value of M as the number of bits used for the bandwidth portion indicator. The base station can notify the terminal of the value of M via higher-layer signaling (e.g., RRC signaling or MAC CE signaling).

[0219] The value of M can be set differently for each carrier. For example, when there are C carriers, B can be configured for the i-th carrier. i {i = 1, 2, ..., C} bandwidth portions. For the i-th carrier, the base station can allocate M... i {i = 1, 2, ..., C} is set to the number of bits used for the bandwidth portion indicator.

[0220] The base station can also set the same number of bits for the bandwidth portion indicator for all carriers. When there are C carriers, Bi{i=1,2,…,C} bandwidth portions can be configured for the i-th carrier. The base station can set the value of M to the number of bits used for the bandwidth portion indicator for each carrier, regardless of B. i What is the value of B? i Less than 2 M , then 2 M Some bits out of the total bits may be left unused (reserved).

[0221] To implement Option 1 above, the bandwidth portion indicated by the bandwidth portion indicator can be pre-specified. More specifically, assuming there are B bandwidth portions and M bits are used as the bandwidth portion indicator, the base station can select Option 2 from the B bandwidth portions. M Each bandwidth portion, and uses an M-bit indicator to map the selected 2 M There are two bandwidth sections. For example, assuming there are B (e.g., 4) bandwidth sections {BWP1, BWP2, BWP3, BWP4} and M (=1) bits used as bandwidth section indicators, the base station can select 2 from the 4 bandwidth sections. M = 2 bandwidth segments (e.g., {BWP1, BWP3}), and the two selected bandwidth segments are mapped using the bandwidth segment indicator value {0, 1}. Table 6 illustrates this mapping.

[0222] Table 6

[0223] Bandwidth section indicator Bandwidth Partial Index 0 BWP1 1 BWP2

[0224] If B < 2 M , then 2 M Some of the bandwidth portion indicator values ​​may not be used (are reserved). For example, assuming there are B (=1) bandwidth portions {BWP1} and M (=1) bits are used as bandwidth portion indicators, the base station may reserve one of the two bandwidth portion indicator values. Here, the mapping can be performed as shown in Table 7.

[0225] Table 7

[0226] Bandwidth section indicator Bandwidth Partial Index 0 BWP1 1 reserve

[0227] The base station can notify the terminal of the above information (the index of the bandwidth portion of each carrier and the corresponding bandwidth portion indicator) through higher-layer signaling (e.g., RRC signaling).

[0228] The terminal can receive configuration information about the bandwidth portion indicator from the base station, interpret the received bandwidth portion indicator according to the configuration information, and determine the bandwidth portion corresponding to the received DCI.

[0229] The terminal can use the DCI field described in Option 1 to identify the bandwidth portion of a given carrier corresponding to the DCI. The terminal can identify the carrier corresponding to the DCI based on a carrier indicator and determine the bandwidth portion of the identified carrier based on a bandwidth portion indicator. The terminal can transmit and receive data via the bandwidth portion of the carrier corresponding to the obtained carrier index and bandwidth portion index.

[0230] Alternative 2

[0231] - Carrier and Bandwidth Part Indicator (CBPI): Indicates the bandwidth portion of a specific carrier corresponding to the received DCI, and can consist of L bits. This can be used to notify the terminal of up to 2 bits corresponding to the combination of carrier index and bandwidth part index. L One of the indexes.

[0232] Regarding Option 2 above, the value of L corresponding to the number of CBPI bits can be fixed as a system parameter. Alternatively, the base station can determine the value of L as the number of bits used for CBPI. The base station can notify the terminal of the value of L via higher-layer signaling (e.g., RRC signaling or MAC CE signaling).

[0233] Regarding Option 2 above, the carriers and their bandwidth portions indicated by CBPI can be pre-specified. More specifically, assuming there are C carriers and Bi (i = 1, 2, ..., C) bandwidth portions in each carrier, then... The base station can determine the value of L as the number of CBPI bits. The base station can select 2L CBP indices (indices to the bandwidth portion of a specific carrier), map the selected CBP indices using L-bit indicators, and notify the terminal of this configuration information.

[0234] For example, suppose there are C (e.g., 4) carriers {C1, C2, C3, C4}, and suppose there are two bandwidth portions {BWP11, BWP12} in carrier C1, two bandwidth portions {BWP21, BWP22} in carrier C2, two bandwidth portions {BWP31, BWP32} in carrier C3, and two bandwidth portions {BWP41, BWP42} in carrier C4, then there can be A (e.g., 8) carrier-bandwidth portion combinations. The CBP index can be formed by combining the carrier index Cx and the bandwidth portion index BWPxy. Table 8 illustrates this mapping.

[0235] Table 8

[0236]

[0237]

[0238] The base station can allocate L (=2) bits for the CBPI size. The base station can select 2 bits from 8 CBP indices. L (For example, 4) CBP indices are used and mapped using CBPI. The base station can select {CBP1, CBP2, CBP5, CBP8} from 8 CBP indices and map them using CBPI {00, 01, 10, 11}. This is summarized in Table 9.

[0239] Table 9

[0240] CBPI CBP Index 00 CBP1 01 CBP2 10 CBP5 11 CBP8

[0241] If A < 2 L , then 2 L Some of the carrier indicator values ​​may not be used (are reserved). For example, assuming there are A (e.g., 3) CBP indices {CBP1, CBP2, CBP3} and L (=2) bits used as CBP indicators, the base station can reserve one of the four CBP indicator values. Here, the mapping can be performed as shown in Table 10.

[0242] Table 10

[0243] CBP indicator CBP Index 00 CBP1 01 CBP2 10 CBP3 11 reserve

[0244] As described above, the base station can notify the terminal of configuration information regarding the mapping between CBP indicators and CBP indices. The base station can also notify the terminal of configuration information regarding the carrier indicated by each CBP index and its bandwidth portion. The base station can notify the terminal of the above information via higher-layer signaling such as RRC signaling or MAC CE signaling.

[0245] The terminal can receive configuration information about the CBP indicator and CBP index from the base station, interpret the received CBP indicator based on the configuration information, and determine the bandwidth portion of the carrier corresponding to the received DCI. The terminal can then transmit and receive data via the bandwidth portion of the carrier corresponding to the obtained carrier and bandwidth portion index.

[0246] Example 5

[0247] The fifth embodiment of this disclosure provides a method for configuring a search space for a downlink control channel.

[0248] Based on the aggregation level, the search space of the 5G downlink control channel can be defined as... Figure 3 The set of indices of the CCE shown. The search space according to the fifth embodiment can be given by equation (5).

[0249] f(Y k,CCE index,AL,number of PDCCH candidates,carrier index,bandwidth partial index)………………..,(5)

[0250] Where f(x) represents a function with x as input.

[0251] According to equation (5), it can be based on Y k The value is used to determine the search space, the Y k The value is a specific value that can be applied to the k-th time slot or subframe. Initial value Y -1 It can be determined by the terminal ID or a specific fixed value. Y can be determined for the terminal-specific search space based on the terminal ID. -1 The value, and can be determined based on a specific value commonly known to all terminals, for the common search space Y. -1 value.

[0252] According to equation (5), the search space can be determined based on the CCE index and the aggregation level. The CCE index to be searched by the terminal can be calculated using the relationship between the CCE index and the terminal ID (or a fixed value) (e.g., modulo operation). Alternatively, the CCE index that can be set for each aggregation level can be calculated using the relationship between the CCE index and the aggregation level value. The set of CCE indexes to be aggregated can also be defined based on the aggregation level value.

[0253] According to equation (5), the search space can be determined based on the number of PDCCH candidates. The number of PDCCH candidates can be different for each aggregation level value. The search space for each aggregation level value can be defined as the set of CCEs corresponding to the number of NR-PDCCH candidates at that aggregation level value.

[0254] According to equation (5), the search space can be determined based on the carrier index. For example, the carrier index can be considered to calculate the offset value applicable to the set of CCE indices constituting a given search space. k The value corresponds to the lowest CCE index that constitutes a PDCCH candidate at a given aggregation level in the k-th time slot or subframe, and the offset value can be applied to the lowest CCE index taking into account the carrier index. This can be represented by equation (6).

[0255] Search space = f(Y) k (Carrier index), CCE index, AL, number of PDCCH candidates)...,(6)

[0256] Where Y k (Carrier index) can be represented by equation (7).

[0257] Y k (Carrier Index) = Y k +m'=Yk +m+M(L)*n CI ………..(7)

[0258] In equation (7), the value of m can be either 0 or M. (L) The range between -1 and M, and (L) This represents the number of PDCCH candidates for aggregation level L. Here, n CI This is the carrier index. When the terminal is configured to monitor the carrier index, the carrier index value obtained from the DCI can be applied. When the terminal is configured not to monitor the carrier index, n CI The value can be set to 0.

[0259] According to equation (5), the search space can be determined based on the bandwidth partial index. For example, the bandwidth partial index can be taken into account to calculate the offset value applicable to the set of CCE indices constituting a given search space. k The value corresponds to the lowest CCE index that constitutes a PDCCH candidate at a given aggregation level in the k-th time slot or subframe, and the bandwidth portion index can be taken into account to apply the offset value to the lowest CCE index. This can be represented by equation (8).

[0260] Search space =

[0261] f(Y k (Bandwidth partial index), CCE index, AL, number of PDCCH candidates)...,(8)

[0262] Where Y k (Bandwidth partial index) can be represented by equation (9).

[0263] Y k (Bandwidth partial index) = Y k +m'=Y k +m+M(L)*n BPI ……,(9)

[0264] The value of m can be either 0 or M. (L) The range between -1 and M, and (L) This represents the number of PDCCH candidates for aggregation level L. Here, n BPI This is the bandwidth partial index. When the terminal is configured to monitor the bandwidth partial index, the bandwidth partial index value obtained from the DCI can be applied. When the terminal is configured not to monitor the bandwidth partial index, n BPI The value can be set to 0.

[0265] According to equation (5), both the carrier index and the bandwidth partial index can be taken into account to determine the search space. For example, the offset values ​​applicable to the set of CCE indices constituting a given search space can be calculated by taking into account the carrier index and the bandwidth partial index. This can be represented by equation (10).

[0266] Search space =

[0267] f(Y k (Carrier index, Bandwidth partial index), CCE index, AL, Number of PDCCH candidates)………….,(10)

[0268] Among them, Y k It can be represented by equation (11).

[0269] Y k (Carrier index, Bandwidth partial index) = Y k +m'=Y k +m+f(carrier index, bandwidth partial index)……….(11)

[0270] In equation (11), f(Y) k (Carrier index, bandwidth partial index) is a specific function that takes the carrier index and bandwidth partial index as input. This can be represented by equation (12).

[0271] f(carrier index, bandwidth partial index) = M(L)*(n) CI +n BPI (12)

[0272] Here, n CI It is a carrier index, and n BPI This is the bandwidth portion index. When the terminal is configured to monitor both the carrier index and the bandwidth portion index, the carrier index value and bandwidth portion index value obtained from the DCI can be applied. When the terminal is configured not to monitor either the carrier index or the bandwidth portion index, n CI or n BPI The corresponding value can be set to 0.

[0273] The search space according to the fifth embodiment can be represented by equation (13).

[0274] Search space =

[0275] f(Y k ,CCE index,AL,number of PDCCH candidates,CBP index)…….(13)

[0276] According to equation (13), the search space can be determined based on the CBP index. The CBP index (defined in the fourth embodiment of this disclosure) is an index value mapped to a combination of the carrier index and the corresponding bandwidth portion index of the carrier. To calculate the search space, the CBP index can be taken into account to calculate the offset values ​​applicable to the set of CCE indices constituting the given search space. This can be represented by equation (14).

[0277] Search space =

[0278] f(Y k (CBP index), CCE index, AL, number of PDCCH candidates)……,(14)

[0279] Where Y k (CBP index) can be represented by equation (15).

[0280] Y k (CBP index) = Y k +m'=Y k +m+M(L)*nC BPI ……….,(15)

[0281] Where the value of m can be between 0 and M (L) The range between -1 and M, and M (L) This refers to the number of PDCCH candidates at aggregation level L. Here, nCBPI is the CBP index. When the terminal is configured to monitor the CBP index, the CBP index value obtained from the DCI can be applied. When the terminal is configured not to monitor the CBP index, the value of nCBPI can be set to 0.

[0282] Next, a description of the operation of the base station and terminal according to the fifth embodiment of this disclosure will be given.

[0283] The base station can determine the terminal's search space by taking into account either the carrier index or the bandwidth portion index. To transmit or receive data for the terminal via a specific bandwidth portion of a given carrier, the base station can transmit the terminal's DCI, based on the search space calculated using the carrier index and the bandwidth portion index.

[0284] For a specific bandwidth portion of a given carrier, the terminal can determine the search space to be monitored by taking into account the carrier index and the bandwidth portion index. The terminal can then perform blind decoding on the DCI within the calculated search space to obtain the DCI.

[0285] Figure 7 and Figure 8These are illustrations of a terminal and a base station, respectively. Each of the terminal and base station includes a transmitter, a receiver, and a controller. The base station and terminal with the above configuration should be able to perform operations for bandwidth portion configuration, bandwidth portion scheduling, DCI transmission, and various signaling within the 5G communication system described as an embodiment.

[0286] like Figure 7 As shown, the terminal may include a processor 701, a receiver 702, and a transmitter 703. The processor 701 may include one or more processors. The processor 701 may be referred to as a controller.

[0287] Processor 701 can control the terminal to operate in accordance with the above disclosure. For example, in an embodiment, processor 701 can control the terminal to perform different decoding operations on the downlink control channel and data channel based on information for bandwidth configuration, bandwidth scheduling, and DCI reception.

[0288] The processor 701 can control the reception of configuration information for a first bandwidth portion and a second bandwidth portion from a base station, decode the DCI for the second bandwidth portion in the control area of ​​the first bandwidth portion based on the size of the downlink control information (DCI) for the first bandwidth portion, and identify the information fields included in the DCI for the second bandwidth portion.

[0289] The processor 701 can identify information fields based on the size information of the DCI decoded in the second bandwidth portion. If the size of the DCI transmitted through the second bandwidth portion is larger than the size of the DCI used for the first bandwidth portion, the processor 701 can control the identification of information fields by determining that the information fields included in the DCI used for the second bandwidth portion are truncated to match the DCI used for the first bandwidth portion.

[0290] If the size of the DCI transmitted through the second bandwidth portion is smaller than the size of the DCI used for the first bandwidth portion, the processor 701 can control the identification information field by determining that the information field included in the DCI used for the second bandwidth portion is zero-padded to match the DCI used for the first bandwidth portion. The information field may correspond to at least one of a frequency resource allocation field and a time resource allocation field. The DCI used for the second bandwidth portion may include a bandwidth portion indicator that indicates the second bandwidth portion.

[0291] In the terminal, receiver 702 and transmitter 703 can be collectively referred to as a transceiver unit. The transceiver unit can transmit signals to and receive signals from the base station. The signals may include control information and data. For this purpose, the transceiver unit may include: an RF transmitter for up-converting and amplifying the frequency of the signal to be transmitted; and an RF receiver for low-noise amplification of the received signal and down-converting the frequency of the received signal. The transceiver unit can receive signals via a radio channel and output signals to processor 701, and can also transmit signals output from processor 701 via a radio channel.

[0292] like Figure 8 As shown, the base station may include a processor 801, a receiver 802, and a transmitter 803. The processor 801 may include one or more processors. The processor 801 may be referred to as a controller.

[0293] The processor 801 can control the base station to operate according to the above disclosure. For example, in an embodiment, the processor 801 can control the base station differently based on operations for bandwidth portion configuration, bandwidth portion scheduling, and DCI transmission. If necessary, the processor 801 can also control the transmission of various additional indicators and configuration information.

[0294] The processor 801 can control the sending of configuration information for the first bandwidth portion and the second bandwidth portion to the terminal, generate a DCI for the second bandwidth portion (the size of which corresponds to the size of the DCI for the first bandwidth portion), and send the DCI for the second bandwidth portion via the control area of ​​the first bandwidth portion.

[0295] If the size of the DCI to be transmitted via the second bandwidth portion is larger than the size of the DCI used for the first bandwidth portion, the information fields included in the DCI used for the second bandwidth portion can be truncated to match the DCI used for the first bandwidth portion.

[0296] If the size of the DCI to be transmitted via the second bandwidth portion is smaller than the size of the DCI used for the first bandwidth portion, the information fields included in the DCI used for the second bandwidth portion may be zero-padded to match the DCI used for the first bandwidth portion. The DCI used for the second bandwidth portion may include information fields, and the information fields may correspond to at least one of a frequency resource allocation field and a time resource allocation field. The DCI used for the second bandwidth portion may include a bandwidth portion indicator that indicates the second bandwidth portion.

[0297] In a base station, receiver 802 and transmitter 803 can be collectively referred to as a transceiver unit. The transceiver unit can transmit signals to and receive signals from a terminal. The signals may include control information and data. For this purpose, the transceiver unit may include: an RF transmitter for up-converting and amplifying the frequency of the signal to be transmitted; and an RF receiver for low-noise amplification of the received signal and down-converting the frequency of the received signal. The transceiver unit can receive signals via a radio channel and output signals to processor 801, and can also transmit signals output from processor 801 via a radio channel.

[0298] According to this disclosure, the terminal can operate on the bandwidth portion of the 5G communication system using ultra-wideband operation, and can operate the 5G communication system more efficiently. This can reduce the number of blind decodes performed by the terminal and reduce the terminal's power consumption.

[0299] Although this disclosure has been shown and described with reference to certain embodiments thereof, those skilled in the art will understand that various changes in form and detail may be made to this disclosure without departing from its scope. Therefore, the scope of this disclosure should not be defined as limited to the embodiments, but rather as defined by the appended claims and their equivalents.

Claims

1. A method performed by a user equipment for communicating in a communication system supporting one or more bandwidth portions, the method comprising: Identify the first bandwidth portion and the second bandwidth portion of the cell configured via radio resource control signaling; Identify a first set of control resources on a first bandwidth portion and a second set of control resources on a second bandwidth portion configured via radio resource control signaling; as well as Based on the activation of the first control resource set on the first bandwidth portion, downlink control information for the second bandwidth portion is obtained. The downlink control information includes bandwidth indicators, frequency domain resource allocation, and time domain resource allocation. The number of bits for the bandwidth portion indicator is defined based on the amount of bandwidth portion configured via radio resource control signaling. The bandwidth portion is mapped starting from the minimum value of the bandwidth portion indicator out of the total value of the bandwidth portion indicator, and... In cases where the number of bandwidth segments is less than the number of values ​​for the bandwidth segment indicator, the maximum value of the bandwidth segment indicator is retained.

2. The method as described in claim 1, in, Frequency domain resource allocation is determined within the second bandwidth portion.

3. The method as described in claim 1, in, A value of 0 for the bandwidth portion indicator corresponds to the first bandwidth portion in ascending order based on the bandwidth portion indicator.

4. The method as described in claim 1, in, Downlink control information also includes carrier indicators, and The bandwidth portion indicator refers to one of the multiple bandwidth portions in the cell configuration indicated by the carrier indicator.

5. The method as described in claim 1, in, When the first size of the frequency domain resource allocation is greater than the second size of the downlink control information required for interpreting the second bandwidth portion, the number of bits in the total bits of the frequency domain resource allocation is used to interpret the frequency domain resource allocation, and This number of bits is equal to the number of bits required for the second bandwidth portion.

6. A method performed by a base station for communicating in a communication system supporting one or more bandwidth portions, the method comprising: Transmit radio resource control signaling, which includes information for a first bandwidth portion of the cell and information for a second bandwidth portion of the cell; Identify a first set of control resources on a first bandwidth portion and a second set of control resources on a second bandwidth portion based on radio resource control signaling configuration; as well as Based on the activation of the first control resource set on the first bandwidth portion, downlink control information for the second bandwidth portion is transmitted. The downlink control information includes bandwidth indicators, frequency domain resource allocation, and time domain resource allocation. The number of bits for the bandwidth portion indicator is defined based on the amount of bandwidth portion configured in the radio resource control signaling. The bandwidth portion is mapped starting from the minimum value of the bandwidth portion indicator out of the total value of the bandwidth portion indicator, and... In cases where the number of bandwidth segments is less than the number of values ​​for the bandwidth segment indicator, the maximum value of the bandwidth segment indicator is retained.

7. The method as described in claim 6, in, Frequency domain resource allocation is determined within the second bandwidth portion.

8. The method as described in claim 6, in, A value of 0 for the bandwidth portion indicator corresponds to the first bandwidth portion in ascending order based on the bandwidth portion indicator.

9. The method as described in claim 6, in, Downlink control information also includes carrier indicators, and The bandwidth portion indicator refers to one of the multiple bandwidth portions in the cell configuration indicated by the carrier indicator.

10. The method as described in claim 6, in, When the first size of the frequency domain resource allocation is greater than the second size of the downlink control information required for interpreting the second bandwidth portion, the number of bits in the total bits of the frequency domain resource allocation is used to interpret the frequency domain resource allocation, and This number of bits is equal to the number of bits required for the second bandwidth portion.

11. A user equipment for communicating in a communication system supporting one or more bandwidth portions, the user equipment comprising: transceiver; as well as The controller is configured as follows: Identify the first bandwidth portion and the second bandwidth portion of the cell configured via radio resource control signaling; Identify a first set of control resources on a first bandwidth portion and a second set of control resources on a second bandwidth portion configured via radio resource control signaling; as well as Based on the activation of the first control resource set on the first bandwidth portion, downlink control information for the second bandwidth portion is obtained. The downlink control information includes bandwidth indicators, frequency domain resource allocation, and time domain resource allocation. The number of bits for the bandwidth portion indicator is defined based on the amount of bandwidth portion configured via radio resource control signaling. The bandwidth portion is mapped starting from the minimum value of the bandwidth portion indicator out of the total value of the bandwidth portion indicator, and... In cases where the number of bandwidth segments is less than the number of values ​​for the bandwidth segment indicator, the maximum value of the bandwidth segment indicator is retained.

12. The user equipment as claimed in claim 11, in, Frequency domain resource allocation is determined within the second bandwidth portion.

13. The user equipment as claimed in claim 11, in, A value of 0 for the bandwidth portion indicator corresponds to the first bandwidth portion in ascending order based on the bandwidth portion indicator.

14. The user equipment as claimed in claim 11, in, Downlink control information also includes carrier indicators, and The bandwidth portion indicator refers to one of the multiple bandwidth portions in the cell configuration indicated by the carrier indicator.

15. The user equipment as claimed in claim 11, in, When the first size of the frequency domain resource allocation is greater than the second size of the downlink control information required for interpreting the second bandwidth portion, the number of bits in the total bits of the frequency domain resource allocation is used to interpret the frequency domain resource allocation, and This number of bits is equal to the number of bits required for the second bandwidth portion.

16. A base station for communicating in a communication system supporting one or more bandwidth portions, the base station comprising: transceiver; as well as The controller is configured as follows: Transmit radio resource control signaling, which includes information for a first bandwidth portion of the cell and information for a second bandwidth portion of the cell; Identify a first set of control resources on a first bandwidth portion and a second set of control resources on a second bandwidth portion based on radio resource control signaling configuration; as well as Based on the activation of the first control resource set on the first bandwidth portion, downlink control information for the second bandwidth portion is transmitted. The downlink control information includes bandwidth indicators, frequency domain resource allocation, and time domain resource allocation. The number of bits for the bandwidth portion indicator is defined based on the amount of bandwidth portion configured in the radio resource control signaling. The bandwidth portion is mapped starting from the minimum value of the bandwidth portion indicator out of the total value of the bandwidth portion indicator, and... In cases where the number of bandwidth segments is less than the number of values ​​for the bandwidth segment indicator, the maximum value of the bandwidth segment indicator is retained.

17. The base station as described in claim 16, in, Frequency domain resource allocation is determined within the second bandwidth portion.

18. The base station as described in claim 16, in, A value of 0 for the bandwidth portion indicator corresponds to the first bandwidth portion in ascending order based on the bandwidth portion indicator.

19. The base station as described in claim 16, in, Downlink control information also includes carrier indicators, and The bandwidth portion indicator refers to one of the multiple bandwidth portions in the cell configuration indicated by the carrier indicator.

20. The base station as described in claim 16, in, When the first size of the frequency domain resource allocation is greater than the second size of the downlink control information required for interpreting the second bandwidth portion, the number of bits in the total bits of the frequency domain resource allocation is used to interpret the frequency domain resource allocation, and This number of bits is equal to the number of bits required for the second bandwidth portion.

Images