Method and apparatus for resource allocation in network collaboration

Abstract

The present disclosure relates to a communication technology and system for integrating a fifth-generation (5G) or pre-5G communication system with IoT technology to support higher data rates after a fourth-generation (4G) communication system such as Long-Term Evolution (LTE). The present disclosure can be applied to intelligent services based on 5G communication technology and IoT-related technologies (e.g., smart home, smart building, smart city, smart car or connected car, healthcare, digital education, retail, security and safety-related services, etc.). According to various embodiments of the present disclosure, a method and apparatus for allocating time and frequency resources to smoothly provide services are provided.

Description

Technical Field

[0001] The present disclosure relates to a wireless communication system, and more particularly, to a method and apparatus for allocating time and frequency resources to smoothly provide services. Background Art

[0002] In order to meet the increasing demand for wireless data services after the commercialization of 4G communication systems, efforts have been made to develop improved 5G communication systems or pre-5G communication systems. For this reason, 5G communication systems or pre-5G communication systems are referred to as ultra-4G network communication systems or post-LTE systems.

[0003] In order to achieve high data transfer rates, implementing 5G communication systems in the mmWave band (e.g., 60 GHz band) is being considered. In 5G communication systems, technologies such as beamforming, massive MIMO, full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and large antenna technologies are discussed as means to mitigate propagation path loss in the ultra-high frequency band and increase propagation transmission distance.

[0004] In addition, 5G communication systems have developed technologies such as evolved small cells, advanced small cells, cloud radio access network (RAN), ultra-dense networks, device-to-device communication (D2D), wireless backhaul, mobile networks, cooperative communication, coordinated multipoint (CoMP), and receive interference cancellation to improve the system network. In addition, 5G systems have developed advanced coding modulation (ACM) schemes (e.g., hybrid FSK and QAM modulation (FQAM) and sliding window superimposed coding (SWSC)) and advanced access technologies (e.g., filter bank multicarrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA)).

[0005] In 5G systems, compared with existing 4G systems, support for various services can be provided. For example, examples of the most representative services may include enhanced mobile broadband (eMBB), ultra-reliable and low-latency communication (URLLC), massive machine-type communication (mMTC), evolved multimedia broadcast / multicast service (eMBMS), etc. In addition, a system that provides URLLC services may be referred to as a URLLC system, and a system that provides eMBB services may be referred to as an eMBB system. In addition, the terms service and system may be used interchangeably.

[0006] Among them, different from the existing 4G system, in the 5G system, URLLC services are considered in a new way, and compared with other services, URLLC services are required to meet the requirements of ultra-reliability (e.g., a packet error rate of approximately 10 to the power of -5) and low latency (e.g., approximately 0.5 milliseconds). To meet these strict requirements, it is necessary to apply a transmission time interval shorter than the transmission time interval (TTI) of eMBB services to URLLC services, and various operation methods using this transmission time interval are being considered.

[0007] Meanwhile, the Internet has evolved into the Internet of Things (IoT) network, in which distributed components such as objects exchange and process information from a human-oriented connection network that generates and consumes information. The Internet of Everything (IoE) technology that combines big data processing technology with IoT technology by connecting to cloud servers, etc., has emerged. To realize the IoT, technical factors such as sensing technology, wired / wireless communication, network infrastructure, service interface technology, and security technology are required, and recently, research has been conducted on technologies such as sensor networks, machine-to-machine (M2M) communication, and machine-type communication (MTC) for connections between objects. In the IoT environment, by collecting and analyzing data generated in connected objects, intelligent Internet technology (IT) services can be provided to create new value for people's lives. The IoT can be applied to fields such as smart homes, smart buildings, smart cities, smart cars, connected cars, smart grids, healthcare, smart home appliances, or high-tech medical services through the integration of conventional information technology (IT) and various industries.

[0008] Therefore, various attempts have been made to apply 5G communication to the IoT network. For example, 5G communication technologies such as sensor networks, machine-to-machine (M2M) communication, and machine-type communication (MTC) have been realized through technologies such as beamforming, MIMO, and array antennas. Cloud RAN, as an application of big data processing technology, can be an example of the integration of 5G technology and IoT technology.

[0009] The above information is presented only as background information to help understand the present disclosure. No determination has been made as to whether any of the above can be applied as prior art with respect to the present disclosure, and no assertion is made. Summary of the Invention

[0010] [Technical Problem]

[0011] One aspect of the present disclosure is to provide a method and apparatus for allocating time and frequency resources in a wireless communication system to smoothly provide services.

[0012] The technical subject matter pursued in the present disclosure may not be limited to the above technical subject matter, and those skilled in the art of the present disclosure can clearly understand other technical subject matters not mentioned through the following description.

[0013] [Solution]

[0014] According to an aspect of the present disclosure, a method for a user equipment (UE) in a communication system is provided, including: sending capability information indicating whether communication based on multiple transmission and reception points is available to a base station; receiving physical downlink shared channel (PDSCH) resource allocation information associated with the multiple transmission and reception points from the base station; and receiving at least one data in the PDSCH sent from the multiple transmission and reception points based on the PDSCH resource allocation information.

[0015] According to another aspect of the present disclosure, a method for a base station in a communication system is provided, the method including: receiving capability information indicating whether communication based on multiple transmission and reception points is available from a user equipment (UE); sending physical downlink shared channel (PDSCH) resource allocation information associated with the multiple transmission and reception points to the UE; and sending at least one data in the PDSCH to the UE based on the PDSCH resource allocation information.

[0016] According to another aspect of the present disclosure, a user equipment (UE) is provided, the user equipment (UE) including a transceiver and a controller, wherein the controller is configured to: send, via the transceiver, capability information indicating whether communication based on multiple transmission and reception points is available to a base station; receive, via the transceiver, physical downlink shared channel (PDSCH) resource allocation information associated with the multiple transmission and reception points from the base station; and receive at least one data in the PDSCH sent from the multiple transmission and reception points based on the PDSCH resource allocation information.

[0017] According to another aspect of the present disclosure, a base station is provided, the base station including a transceiver and a controller, wherein the controller is configured to: receive, via the transceiver, capability information indicating whether communication based on multiple transmission and reception points is available from a user equipment (UE); send, via the transceiver, physical downlink shared channel (PDSCH) resource allocation information associated with the multiple transmission and reception points to the UE; and send, via the transceiver, at least one data in the PDSCH to the UE based on the PDSCH resource allocation information.

[0018] [Advantageous Effects]

[0019] According to an embodiment of the present disclosure, time and frequency resources can be effectively allocated in a wireless communication system.

[0020] The effects that can be obtained from the present disclosure may not be limited to the above effects, and through the following description, those skilled in the art of the present disclosure can clearly understand other effects not mentioned. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] To more fully understand the present disclosure and its advantages, reference is now made to the following description in connection with the accompanying drawings, in which like reference numerals represent like components:

[0022] Figure 1 A diagram showing the time-frequency domain transmission structure of an LTE, LTE-A, NR or similar wireless communication system of the present disclosure;

[0023] Figure 2 A diagram showing the frame, sub-frame and time slot structure in 5G of the present disclosure;

[0024] Figure 3 A diagram showing an example of bandwidth part (BWP) configuration according to an embodiment of the present disclosure;

[0025] Figure 4 A diagram showing an example of BWP indication and switching according to an embodiment of the present disclosure;

[0026] Figure 5 A diagram showing an example of configuring a control resource set for a downlink control channel according to an embodiment of the present disclosure;

[0027] Figure 6 A diagram showing an example of PDSCH frequency domain resource allocation according to an embodiment of the present disclosure;

[0028] Figure 7 A diagram showing an example of time domain resource allocation of NR according to an embodiment of the present disclosure;

[0029] Figure 8 A diagram showing an example of time domain resource allocation according to the subcarrier spacing of a data channel and a control channel according to an embodiment of the present disclosure;

[0030] Figure 9 A diagram showing the eNB and UE protocol stacks when performing single cell, carrier aggregation and dual connectivity according to an embodiment of the present disclosure;

[0031] Figure 10 A diagram showing an example of joint transmission (JT) technology and wireless resource allocation for each TRP according to circumstances according to an embodiment of the present disclosure.

[0032] Figure 11 A diagram showing four examples of DCI design for NC-JT support according to an embodiment of the present disclosure;

[0033] Figure 12 A diagram showing an example of step-by-step FD-RA according to an embodiment of the present disclosure;

[0034] Figure 13 A diagram showing PDCCH monitoring opportunities according to PDSCH mapping types according to an embodiment of the present disclosure;

[0035] Figure 14 A diagram showing a method of monitoring two or more PDSCHs according to an embodiment of the present disclosure;

[0036] Figure 15 A diagram showing another example of a method of monitoring two or more PDSCHs according to an embodiment of the present disclosure;

[0037] Figure 16 A block diagram showing the structure of a UE according to an embodiment of the present disclosure;

[0038] Figure 17 A block diagram showing the structure of an eNB according to an embodiment of the present disclosure; and

[0039] Figure 18 A diagram showing an example of the relationship between an RBG and a TRP and a bitmap for RBG allocation according to an embodiment of the present disclosure. Detailed Description

[0040] Before proceeding with the following detailed description, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document: The terms "include" and "comprise," and derivatives thereof, mean inclusively including without limitation; the term "or" is inclusive, meaning and / or; the phrases "associated with" and "associated therewith," and derivatives thereof, may mean: include, be included within, interconnect with, contain, be contained within, be connected to or connected with, be coupled to or coupled with, be communicable with, cooperate with, be interwoven, be juxtaposed, be adjacent to, be bound to or bound with, have, have the property of, etc.; and the term "controller" means any device, system, or portion thereof that controls at least one operation, such a device may be implemented in hardware, firmware, software, or a combination of at least two of hardware, firmware, or software. It should be noted that the functions associated with any particular controller may be centralized or distributed, whether local or remote.

[0041] In addition, the various functions described below can be implemented or supported by one or more computer programs, each of which is formed of computer-readable program code and is contained in a computer-readable medium. The terms "application" and "program" refer to one or more computer programs, software components, instruction sets, procedures, functions, objects, classes, instances, related data, or portions thereof suitable for implementation in appropriate computer-readable program code. The phrase "computer-readable program code" includes any type of computer code, including source code, object code, and executable code. The phrase "computer-readable medium" includes any type of medium that can be accessed by a computer, such as read-only memory (ROM), random access memory (RAM), hard disk drives, optical discs (CDs), digital video discs (DVDs), or any other type of memory. A "non-transitory" computer-readable medium excludes wired, wireless, optical, or other communication links that transmit transitory electrical signals or other signals. A non-transitory computer-readable medium includes media that can permanently store data, as well as media that can store data and then rewrite the data, such as rewritable optical discs or erasable storage devices.

[0042] Certain words and phrases are defined throughout this patent document, and those of ordinary skill in the art should understand that, in many if not most cases, such definitions apply to both the existing and future use of the words and phrases so defined.

[0043] The following discussion of Figures 1 to 18 and the various embodiments for describing the principles of the present disclosure in this patent document are merely exemplary and should not be construed in any way as limiting the scope of the present disclosure. Those skilled in the art will appreciate that the principles of the present disclosure can be implemented in any appropriately arranged system or device.

[0044] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0045] When describing the exemplary embodiments of the present disclosure, descriptions related to well-known technical content in the technical field to which the present disclosure pertains and not directly related to the present disclosure will be omitted. The purpose of this omission of unnecessary descriptions is to prevent confusion of the main idea of the present disclosure and to more clearly convey the main idea.

[0046] For the same reason, in the drawings, some elements may be exaggerated, omitted, or shown schematically. In addition, the dimensions of each element do not fully reflect the actual dimensions. In the drawings, the same or corresponding elements have the same reference numerals.

[0047] Advantages and features of the present disclosure, and ways to implement them, will be apparent by referring to the embodiments described in detail below in conjunction with the accompanying drawings. However, the present disclosure is not limited to the embodiments set forth below, but may be implemented in various different forms. The following embodiments are provided only to fully disclose the present disclosure and to inform those skilled in the art of the scope of the present disclosure, and the present disclosure is defined only by the scope of the appended claims. Throughout the specification, the same or similar reference numerals denote the same or similar elements.

[0048] Here, it will be understood that each block of the flowchart, and combinations of blocks in the flowchart, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions executed by the processor of the computer or other programmable data processing apparatus create a module for implementing the functions specified in one or more flowchart blocks. These computer program instructions can also be stored in a computer-usable or computer-readable memory, which can direct a computer or other programmable data processing apparatus to operate in a particular manner, such that the instructions stored in the computer-usable or computer-readable memory produce an article of manufacture including an instruction module for implementing the functions specified in one or more flowchart blocks. The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus, thereby producing a computer-implemented process, such that the instructions executed on the computer or other programmable apparatus provide steps for implementing the functions specified in one or more flowchart blocks.

[0049] And each block of the flowchart can represent a module, segment, or portion of code that includes one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions recorded in the blocks may occur in sequence. For example, two blocks shown in succession may in fact be executed substantially simultaneously, or the blocks may sometimes be executed in the reverse order, depending on the functions involved.

[0050] As used herein, a "unit" refers to a software element or a hardware element that performs a predetermined function, such as a Field Programmable Gate Array (FPGA) or an Application Specific Integrated Circuit (ASIC). However, the meaning of "unit" is not always limited to software or hardware. A "unit" can be configured to be stored in an addressable storage medium or executed by one or more processors. Thus, a "unit" includes, for example, software elements, object-oriented software elements, class elements or task elements, processes, functions, attributes, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and parameters. The elements and functions provided by a "unit" can be combined into a smaller number of elements, "units", or divided into a larger number of elements, "units". In addition, the elements and "units" can be implemented as one or more CPUs within a reproduction device or a secure multimedia card. Further, according to some embodiments, a "~ unit" can include one or more processors.

[0051] Hereinafter, the operating principle of the present disclosure will be described in detail with reference to the accompanying drawings. When determining that a detailed description of a related known configuration or function may unnecessarily obscure the subject matter of the present disclosure during the description of the following disclosure, the detailed description of the related known configuration or function included herein will be omitted. The terms to be described below are terms defined in consideration of the functions in the present disclosure and may vary depending on a user, the user's intention, or custom. Thus, the definitions of the terms should be based on the content of the entire specification. Hereinafter, the base station is an object for performing resource allocation for a terminal and may be at least one of a gNodeB, an eNode B, a Node B, a Base Station (BS), a radio access unit, a base station controller, or a node on a network. The terminal may include a User Equipment (UE), a Mobile Station (MS), a cellular phone, a smart phone, a computer, or a multimedia system capable of performing a communication function. Of course, the base station and the terminal are not limited to the above examples.

[0052] Hereinafter, the present disclosure describes a technique for a UE to receive broadcast information from an eNB in a wireless communication system. The present disclosure relates to a communication scheme and its system for fusing a 5G communication system and IoT technology, and the 5G communication system is for supporting a higher data rate after a 4G system. The present disclosure can be applied to intelligent services based on 5G communication technology and IoT-related technology (e.g., smart home, smart building, smart city, smart car or connected car, healthcare, digital education, retail, security and safety-related services, etc.).

[0053] For ease of description, terms related to broadcast information, terms related to control information, terms related to communication coverage, terms related to state changes (e.g., events), terms related to network entities, terms related to messages, terms related to device components, etc. used in the following description are shown. Therefore, the present disclosure is not limited to the terms described below, and other terms with equivalent technical meanings may be used.

[0054] In the following, for ease of the following description, some terms and names defined in the 3rd Generation Partnership Project Long Term Evolution (3GPP LTE) standard may be used. However, the present disclosure is not limited to the above terms and names, and may be equivalently applied to systems conforming to other standards.

[0055] Wireless communication systems have evolved from early systems that provided voice-oriented services to broadband wireless communication systems that provide high-speed and high-quality packet data services such as those in the following communication standards: High Speed Packet Access (HSPA), Long Term Evolution (LTE) or Evolved Universal Terrestrial Radio Access (E-UTRA), LTE-Advanced (LTE-A) and LTE-pro of 3GPP, High Rate Packet Data (HRPD) and Ultra Mobile Broadband (UMB) of 3GPP2, and 802.16e of IEEE.

[0056] As a representative example of a broadband wireless communication system, the LTE system employs Orthogonal Frequency Division Multiplexing (OFDM) for downlink (DL) transmission and Single Carrier Frequency Division Multiple Access (SC-FDMA) for UL transmission. UL refers to the radio link through which a UE or MS sends data or control signals to an eNB or BS, and DL refers to the radio link through which an eNB or BS sends data or control signals to a UE or MS. In such a multiple access scheme, the time-frequency resources carrying the data and control information of each user are generally allocated and used without overlapping to achieve orthogonality, thereby distinguishing the data and control information.

[0057] As a future communication system after LTE, i.e., the 5G communication system should be able to freely reflect the various needs of users and service providers, and thus should support services that meet various needs. Services considered for the 5G communication system include enhanced mobile broadband (eMBB), massive machine type communication (mMTC), and ultra-reliable low latency communication (URLLC), etc.

[0058] According to some embodiments, eMBB is intended to provide a higher data rate than that supported by existing LTE, LTE-A, or LTE-Pro. For example, in a 5G communication system, for an eNB, eMBB should be able to provide a peak data rate of 20 Gbps in the downlink and 10 Gbps in the uplink. At the same time, an increased user-perceived data rate for the UE must be provided. To meet such requirements, improved transmission and reception techniques are needed, including improved multiple-input multiple-output (MIMO) transmission techniques. In addition, by using a frequency band wider than 20 MHz in the frequency band from 3 GHz to 6 GHz or 6 GHz or higher instead of the 2 GHz frequency band used by current LTE, the data rate required for the 5G communication system can be met.

[0059] At the same time, mMTC is considered to support application services such as the Internet of Things (IoT) in a 5G communication system. To effectively provide the IoT, mMTC may need to support the access of a large number of UEs in a cell, improve the coverage of the UEs, improve battery life, reduce the cost of the UEs, etc. Since the IoT is connected to various sensors and various devices to provide communication functions, it should be able to support a large number of UEs in a cell (e.g., 1,000,000 UEs / km2). In addition, UEs supporting mMTC may be located in shadow areas where the cell is not covered due to the characteristics of the service (such as the basement of a building), thus requiring a wider coverage than that provided by other services in the 5G communication system. UEs supporting mMTC should be configured as low-cost UEs and may require a significantly longer battery life because it is difficult to replace the battery of the UE frequently.

[0060] Finally, URLLC is a cellular-based wireless communication service for mission-critical purposes and should provide communication with ultra-low latency and ultra-high reliability as a service for remote control of robots or machines, industrial automation, drones, remote healthcare, emergency alerts, etc. For example, a service supporting URLLC should meet an air interface latency of less than 0.5 milliseconds and at the same time have a packet error rate requirement of 10 to the power of -5 or less. Therefore, for a service supporting URLLC, the 5G system should provide a smaller transmission time interval (TTI) than other services, and at the same time, a design requirement of allocating wide resources in the frequency band is needed. However, the above mMTC, URLLC, and eMBB are merely examples of different service types, and the service types to which the present disclosure is applied are not limited to the above examples.

[0061] The services considered in the above 5G communication system should be integrated and provided based on a framework with each other. That is, for effective resource management and control, preferably, each service is integrated, controlled, and transmitted as a system rather than being executed independently.

[0062] In addition, in the following description, the LTE, LTE-A, LTE Pro, or NR system will be used as an example to describe embodiments of the present disclosure. However, embodiments of the present disclosure can be applied to other communication systems having a similar technical background or channel form. In addition, embodiments of the present disclosure can be applied to other communication systems with some modifications within the scope determined by those skilled in the art without departing from the scope of the present disclosure.

[0063] Hereinafter, the frame structure of the 5G system will be described in more detail with reference to the drawings.

[0064] Figure 1 A diagram showing the basic structure of the time-frequency domain, which is a radio resource area for transmitting data or control channels in the 5G system of the present disclosure.

[0065] In Figure 1 , the horizontal axis represents the time domain and the vertical axis represents the frequency domain. The basic unit of resources in the time domain and the frequency domain is a resource element (RE) 1-01, which can be defined as 1 orthogonal frequency division multiplexing (OFDM) symbol 1-02 on the time axis and 1 subcarrier 1-03 on the frequency axis. A continuous (e.g., 12) REs in the frequency domain can form a resource block (RB) 1-04.

[0066] Figure 2 A diagram showing the slot structure in the 5G system according to the present disclosure.

[0067] In Figure 2 , an example of the structure of a frame 2-00, a subframe 2-01, and a slot 2-02 is shown. A frame 2-00 can be defined as 10 ms. A subframe 2-01 can be defined as 1 ms. Therefore, a frame 2-00 can be composed of a total of 10 subframes 2-01. A slot 2-02 or 2-03 can be defined as 14 OFDM symbols (i.e., the number of symbols per slot = 14). A subframe 2-01 can be composed of one or more slots 2-02 and 2-03, and the number of slots 2-02 and 2-03 in each subframe 2-01 can vary according to the configured value μ 2-04 or 2-05 of the subcarrier spacing. In Figure 2 's example, the case where the configured value of the subcarrier spacing is μ = 0 (2-04) or μ = 1 (2-05) is shown. If μ = 0 (2-04), then a subframe 2-01 can be composed of one slot 2-02, and if μ = 1 (2-05), then a subframe 2-01 can be composed of two slots 2-03. That is, the number of slots per subframe can vary according to the configured value μ of the subcarrier spacing, and thus the number of slots per frame It can be varied. It can be defined in Table 1 below according to each subcarrier spacing configuration μ and

[0068] [Table 1]

[0069]

[0070] In NR, a component carrier (CC) or serving cell can consist of up to 250 RBs or more RBs. Therefore, when the UE always receives the entire serving cell bandwidth (such as in LTE), the power consumption of the UE may be extreme. To solve this problem, the eNB can configure one or more bandwidth parts (BWPs) for the UE so that it can support the UE to change the reception area in the cell. In NR, the eNB can configure the "initial BWP" for the UE through the MIB, and this initial BWP is the bandwidth of CORESET#0 (or the common search space (CSS)). Next, the eNB can configure the initial BWP (the first BWP) of the UE through RRC signaling and can notify at least one BWP configuration information that can be indicated by DCI in the future. Next, the eNB can indicate which frequency band the UE uses by notifying the BWP ID via DCI. If the UE does not receive DCI at the currently allocated BWP for a specific time or longer, the UE returns to the "default BWP" and tries to receive DCI.

[0071] Figure 3 A diagram showing an example of partial bandwidth configuration according to an embodiment of the present disclosure.

[0072] Figure 3 An example is shown in which the UE bandwidth 3-00 is configured as two BWPs (i.e., BWP#13-05 and BWP#23-10). The eNB can configure one or more BWPs for the UE and can configure the information in Table 2 below for each BWP.

[0073] [Table 2]

[0074]

[0075]

[0076] In addition to the configuration information, various parameters related to the BWP can also be configured for the UE. The eNB can send the above information to the UE through higher layer signaling (such as RRC signaling). At least one of the configured one or more BWPs can be activated. Information about whether the configured BWP is activated can be sent semi-statically from the eNB to the UE through RRC signaling, or this information can be sent dynamically through the MAC control element (CE) or DCI.

[0077] The configuration of BWPs supported by a 5G communication system can be used for various purposes.

[0078] For example, when the bandwidth supported by a UE is less than the system bandwidth, this can be supported by the configuration of BWPs. For example, by configuring the frequency positions of BWPs (configuration information 1) for the UE in Table 2, the UE can transmit and receive data at specific frequency positions within the system bandwidth.

[0079] As another example, an eNB can configure multiple BWPs for a UE to support different numerology sets. For example, to support data transmission and reception to the UE using a subcarrier spacing of 15 kHz and a subcarrier spacing of 30 kHz, two BWPs can be respectively configured to use subcarrier spacings of 15 kHz and 30 kHz. Different BWPs can be FDM, and when it is desired to transmit / receive data at a specific subcarrier spacing, the BWP configured with the corresponding subcarrier spacing can be activated.

[0080] As another example, for the purpose of reducing the power consumption of a UE, an eNB can configure BWPs with different bandwidth sizes for the UE. For example, when a UE supports a relatively large bandwidth (e.g., a bandwidth of 100 MHz) and always transmits and receives data in the corresponding bandwidth, this UE may cause a relatively large power consumption. In particular, in the absence of traffic, for a large bandwidth of 100 MHz, monitoring unnecessary downlink control channels is significantly inefficient in terms of power consumption. Therefore, to reduce the power consumption of the UE, the eNB can configure a BWP with a relatively small bandwidth, such as a BWP of 20 MHz. In the absence of traffic, the UE can perform monitoring operations in the 20-MHz BWP, and when data is generated, it can use the 100-MHz BWP to transmit and receive data according to the instructions of the eNB.

[0081] Figure 4 A diagram showing a method for dynamically configuring the handover of BWPs according to an embodiment of the present disclosure is shown.

[0082] As shown in Table 2, an eNB can configure one or more BWPs for a UE, and can notify information about the bandwidth, frequency position, and numerology set of the BWP as the configuration of each BWP. Figure 4 An example of configuring two BWPs (BWP#1 4-05 and BWP#2 4-10) for one UE within the UE bandwidth 4-00 is shown. One or more BWPs can be activated among the configured bandwidths, and in Figure 4 an example of activating one BWP is shown. In Figure 4Among them, BWP #1 4-02 is activated among the BWPs configured in time slots #0 4-25, and the UE can monitor the PDCCH in control resource set #1 4-45 configured in BWP #1 4-05, and can send and receive data 4-55 in BWP #1 4-05. The control resource set used by the UE to receive the PDCCH can vary according to which BWP is activated among the configured BWPs, and the bandwidth used by the UE to monitor the PDCCH can vary.

[0083] The eNB can also send an indicator for the configuration to switch the BWP to the UE. Here, the configuration to switch the BWP can be considered the same as activating a specific BWP (e.g., switching the activation from BWP A to BWP B). The eNB can send a configuration switch indicator to the UE in a specific time slot. Here, the UE can receive the configuration switch indicator from the eNB, and can determine the BWP to be activated by applying the switched configuration according to the configuration switch indicator starting from a specific time point, and monitor the PDCCH in the control resource set configured in the activated BWP.

[0084] In Figure 4 Among them, the eNB can send a configuration switch indication 4-15 to the UE, and this configuration switch indication 4-15 is used to indicate that the BWP to be activated in time slot #1 4-30 is switched from the existing BWP #1 4-05 to BWP #2 4-10. The UE can receive the corresponding indicator, and then can activate BWP #2 6-10 according to the content of the indicator. In this case, a transition time 4-20 for switching the BWP may be required, so the time point for switching and applying the BWP to be activated can be determined. Figure 4 It shows a case where a transition time 4-20 of one time slot is required after receiving the configuration switch indicator 4-15. Data transmission and reception may not be performed during the transition time 4-20. Therefore, BWP #2 4-10 can be activated in time slot #2 4-35 to perform operations of sending and receiving control channels and data to the corresponding BWP.

[0085] The eNB can pre-configure one or more BWPs for the UE through higher layer signaling (e.g., RRC signaling), and can indicate activation in the following method: the mapping between the configuration switch indicator 4-15 and one of the configurations of the BWPs pre-configured by the eNB. For example, an indicator of log2N bits can select and indicate one of N predetermined BWPs. Table 3 below shows an example of using a 2-bit indicator to indicate the configuration information about the BWP.

[0086] [Table 3]

[0087] Indicator value BWP configuration 00 BWP configuration A configured by higher layer signaling 01 BWP configuration B configured by higher layer signaling 10 BWP configuration C configured by higher layer signaling 11 BWP configuration D configured by higher layer signaling

[0088] The above-mentioned configuration switching indicator 4-15 for the BWP can be sent from the eNB to the UE in the form of media access control (MAC) control element (CE) signaling or L1 signaling (e.g., common DCI, group common DCI, or UE-specific DCI).

[0089] According to the configuration switching indicator 4-15 for the above-mentioned BWP, at which time point to apply BWP activation may depend on the following. At which time point to apply the configuration switching may depend on a predetermined value (e.g., apply after N (≥1) time slots after receiving the configuration switching indicator). Alternatively, at which time point to apply the configuration switching may be configured by the eNB to the UE through higher layer signaling (e.g., RRC signaling), or may be configured by the eNB to the UE by including a part of it in the content of the configuration switching indicator 4-15 and sending it. Alternatively, the method of determining at which time point to apply the configuration switching may be combined with the above methods. After receiving the configuration switching indicator 4-15 for the BWP, the UE may start applying the switched configuration from the time point obtained through the above method.

[0090] Hereinafter, the downlink control channel in the 5G communication system will be described in more detail with reference to the accompanying drawings.

[0091] Figure 5 A diagram showing an example of a control resource set (CORESET) for transmitting a downlink control channel in a 5G wireless communication system according to an embodiment of the present disclosure.

[0092] Figure 5 An example showing that the BWP 5-10 of the UE is configured on the frequency axis and two control resource sets (control resource set #1 5-01 and control resource set #2 5-02) are configured in one time slot 5-20 on the time axis. On the frequency axis, the control resource sets 5-01 and 5-02 can be configured in a specific frequency resource 5-03 within the entire UE BWP 5-10. The control resource sets 5-01 and 5-02 can be configured as one or more OFDM symbols on the time axis and can be defined as the control resource set duration 5-04. In Figure 5 the example, the control resource set #1 5-01 is configured by a control resource set duration of two symbols, and the control resource set #2 5-02 is configured by a control resource set duration of one symbol.

[0093] The eNB may configure the control resources set in 5G to the UE through higher layer signaling (e.g., system information, master information block (MIB), radio resource control (RRC) signaling). Configuring a control resource set for the UE means providing information such as the control resource set identifier, the frequency location of the control resource set, and the symbol length of the control resource set. For example, the information in Table 4 may be included in the above information.

[0094] [Table 4]

[0095]

[0096] In Table 4, the tci-StatesPDCCH (referred to as TCI state for short) configuration information may include information about one or more synchronization signal (SS) / physical broadcast channel (PBCH) block indexes or information about channel state information reference signal (CSI-RS) indexes that are in a quasi-co-location (QCL) relationship with the DMRS transmitted from the corresponding control resource set.

[0097] Hereinafter, a method for allocating time and frequency resources for data transmission in NR will be described.

[0098] In NR, in addition to the candidate allocation of frequency domain resources indicated by the BWP, the following detailed frequency domain resource allocation (FD-RA) methods are also provided.

[0099] Figure 6 A diagram showing an example of PDSCH frequency domain resource allocation according to an embodiment of the present disclosure.

[0100] Figure 6 Three frequency domain resource allocation (FD-RA) methods of type 0 6-00, type 1 6-05, and dynamic switching 6-10 that can be configured by a higher layer in NR are shown.

[0101] If the UE is configured by higher layer signaling (6-00) to use only resource type 0, some downlink control information (DCI) for allocating PDSCH to the UE has a bitmap composed of bits numbered by NRBG. The conditions for this case will be described later. In this case, NRBG refers to the number of resource block groups (RBGs) determined according to the BWP size indicated by the BWP indicator and the higher layer parameter RBG-size as shown in Table 5 below, and data is sent to the RBGs indicated as "1" in the bitmap.

[0102] [Table 5]

[0103] Bandwidth part size Configuration 1 Configuration 2 1-36 2 4 37-42 4 8 73-144 8 16 145-275 16 16

[0104] If the UE is configured to use only resource type 1 via higher layer signaling (6-05), some DCIs for allocating the PDSCH to the UE have frequency domain resource allocation information consisting of bits numbered by The conditions for this case will be described later. In this way, the eNB can configure the starting virtual RB (VRB) 6-20 and the length 6-25 of the frequency domain resources continuously allocated from the starting VRB 6-20. Each VRB is mapped to a PRB in a 1:1 manner by specific rules.

[0105] If the UE is configured to use resource type 0 and resource type 1 via higher layer signaling (6-10), some DCIs for allocating the PDSCH to the UE have frequency domain resource allocation information that includes the payload 6-15 for configuring resource type 0 and the larger value 6-35 among the payloads 6-20 and 6-25 for configuring resource type 1. The conditions for this case will be described later. In this case, if one bit is added to the first part (most significant bit (MSB)) of the frequency domain resource allocation information in the DCI to obtain "0", this indicates the use of resource type 0, and when "1" is obtained, this indicates the use of resource type 1.

[0106] Figure 7 A diagram showing an example of time domain resource allocation of NR according to an embodiment of the present disclosure.

[0107] Referring to Figure 7 , the eNB can indicate the time domain position of the PDSCH resource according to the scheduling offset (K0) value within one time slot dynamically indicated by the DCI, the start position 7-00 and length 7-05 of the OFDM symbol, and the subcarrier spacing μ of the data channel and the control channel configured by higher layer signaling PDSCH and μ PDCCH thereof.

[0108] Figure 8 A diagram showing an example of time domain resource allocation according to the subcarrier spacing of the data channel and the control channel according to an embodiment of the present disclosure.

[0109] Referring to Figure 8 , when the subcarrier spacings of the data channel and the control channel are the same (8-00, μ PDSCH =μ PDCCH ), since the number of time slots for data and control is the same, the eNB and the UE can know the occurrence of the scheduling offset according to the predetermined time slot offset K0. On the other hand, when the subcarrier spacings of the data channel and the control channel are different (8-05, μ PDSCH ≠μ PDCCH) Since the number of time slots for data and control is different, the eNB and UE can know the occurrence of scheduling offset based on the subcarrier spacing of the PDCCH according to the predetermined time slot offset K0.

[0110] In NR, various types of DCI formats for effective control channel reception of the UE are provided for the purposes shown in Table 6 below.

[0111] [Table 6]

[0112]

[0113]

[0114] For example, the eNB can use DCI format 0_0 or DCI format 0_1 to allocate (schedule) the PDSCH to a cell.

[0115] When transmitted with a CRC scrambled by a cell radio network temporary identifier (C-RNTI), a configured scheduling RNTI (CS-RNTI), or a new-RNTI, DCI format 0_1 includes at least the following information:

[0116] ● Identifier of the DCI format (1 bit): Always configured as 1, as the DCI format indicator

[0117] ● Frequency domain resource allocation (N RBG bits or bits): Indicates the frequency domain resource allocation, and if monitoring DCI format 1_0 in the UE-specific search space, is the size of the activated DL BWP. Otherwise, is the size of the initial DL BWP. N REG is the number of resource block groups. The detailed method is called frequency domain resource allocation.

[0118] ● Time domain resource allocation (0 to 4 bits): Indicates the time domain resource allocation according to the above description.

[0119] ● VRB to PRB mapping (1 bit): If it is "0", this indicates non-interleaving, and if it is "1", this indicates interleaved VRP to PRB mapping.

[0120] ● Modulation and coding scheme (5 bits): Indicates the modulation order and coding rate for PDSCH transmission.

[0121] ● New data indicator (1 bit): Indicates whether the PDSCH is an initial transmission or a retransmission according to whether a handover occurs.

[0122] ● Redundancy version (2 bits): Indicates the redundancy version for PDSCH transmission.

[0123] ● HARQ process number (4 bits): Indicates the number of HARQ processes used for PDSCH transmission.

[0124] ● Downlink allocation index (2 bits): DAI indicator

[0125] ● TPC command for PUCCH used for scheduling (2 bits): PUCCH power control indicator

[0126] ● PUCCH resource indicator (3 bits): Indicates one of the 8 resources configured by the higher layer as the PUCCH resource indicator.

[0127] ● PDSCH to HARQ_feedback timing indicator (3 bits): Indicates one of the 8 feedback timing offsets configured by the higher layer as the HARQ feedback timing indicator.

[0128] When transmitted with a CRC scrambled by C-RNTI, CS-RNTI, or new-RNTI, DCI format 1_1 includes at least the following information:

[0129] ● Identifier for the DCI format (1 bit): Always configured as 1 as the DCI format indicator

[0130] ● Carrier indicator (0 or 3 bits): Indicates the CC (or cell) to which the PDSCH allocated by the corresponding DCI will be transmitted.

[0131] ● "Bandwidth part indicator (0, 1, or 2 bits): Indicates the BWP to which the PDSCH allocated by the corresponding DCI will be transmitted.

[0132] ● Frequency domain resource allocation (payload is determined according to the frequency domain resource allocation): Indicates the frequency domain resource allocation, and is the size of the activated DL BWP. Its detailed method is called frequency domain resource allocation.

[0133] ● Time domain resource allocation (0 to 4 bits): Represents the time domain resource allocation as described above.

[0134] ● VRB to PRB mapping (0 bits or 1 bit): If it is "0", this indicates non-interleaved, and if it is "1", this indicates interleaved VRP to PRB mapping. If the frequency domain resource allocation is configured as resource type 0, 0 bits are obtained.

[0135] ● PRB bundling size indicator (0 or 1 bit): If the higher layer parameter PRB-BundlingType is not configured or configured as "static", 0 bits are obtained, and if the higher layer parameter PRB-BundlingType is configured as "dynamic", 1 bit is obtained.

[0136] ● Rate matching indicator (0 bits or 1 bit or 2 bits): Indicates the rate matching pattern.

[0137] ● ZP CSI-RS trigger (0 bits or 1 bit or 2 bits): Indicator for triggering aperiodic ZP CSI-RS

[0138] ● For transport block 1:

[0139] a) ■ Modulation and coding scheme (5 bits): Indicates the modulation order and coding rate of PDSCH transmission.

[0140] b) ■ New data indicator (1 bit): Indicates whether the PDSCH is an initial transmission or a retransmission based on whether a handover has occurred.

[0141] c) ■ Redundancy version (2 bits): Indicates the redundancy version used for PDSCH transmission.

[0142] ● For transport block 2:

[0143] a) ■ Modulation and coding scheme (5 bits): Indicates the modulation order and coding rate for PDSCH transmission.

[0144] b) ■ New data indicator (1 bit): Indicates whether the PDSCH is an initial transmission or a retransmission based on whether a handover has occurred.

[0145] c) ■ Redundancy version (2 bits): Indicates the redundancy version used for PDSCH transmission.

[0146] ● HARQ process number (4 bits): Indicates the number of HARQ processes used for PDSCH transmission.

[0147] ● Downlink allocation index (0 bits or 2 bits or 4 bits): DAI indicator

[0148] ● TPC command for PUCCH used for scheduling (2 bits): PUCCH power control indicator

[0149] ● PUCCH resource indicator (3 bits): Indicates one of the 8 resources configured by the higher layer as the PUCCH resource indicator.

[0150] ● PDSCH to HARQ_feedback timing indicator (3 bits): Indicates one of the 8 feedback timing offsets configured by the higher layer as the HARQ feedback timing indicator.

[0151] ● Antenna port (4 bits or 5 bits or 6 bits): Indicates the DMRS port CDM group without data.

[0152] ● Transmission Configuration Indicator (0 or 3 bits): TCI Indicator

[0153] ● SRS Request (2 bits or 3 bits): SRS Transmission Request Indicator

[0154] ● CBG Transmission Information (0 bits or 2 bits or 4 bits or 6 bits or 8 bits): Indicator for notifying whether the code block group within the allocated PDSCH is transmitted. "0" means not sending the corresponding CBG, and "1" means sending the corresponding CBG.

[0155] ● CBG Clearing Information (0 or 1 bit): Indicator for notifying whether the previous CBG is contaminated. If it is "0", this means the CBG may be contaminated, and if it is "1", this means the CBG may be combinable upon receiving a retransmission.

[0156] ● DMRS Sequence Initialization (0 or 1 bit): DMRS Scrambling ID Selection Indicator

[0157] The number of DCIs with different sizes that can be received by the UE in each time slot in the corresponding cell is up to 4. The number of DCIs with different sizes scrambled by C-RNTI that can be received by the UE in each time slot in the corresponding cell is up to 3.

[0158] Figure 9 Diagrams showing the structures of the eNB and UE radio protocols when performing single-cell, carrier aggregation, and dual connectivity according to an embodiment of the present disclosure.

[0159] Refer to Figure 9 , the radio protocols of the next-generation telecommunication system include the NR Service Data Adaptation Protocol (SDAPS) 9-25 and 9-70, NR Packet Data Convergence Protocol (PDCP) 9-30 and 9-65, NR RLC Link Control 9-35 and 9-60, and NR Medium Access Control (MAC) 9-40 and 9-55 in the UE and NR eNB, respectively.

[0160] The main functions of NR SDAPS 9-25 and 9-70 may include some of the following functions.

[0161] - Transmission of user plane data

[0162] - Mapping between QoS flows and DRBs for both DL and UL

[0163] - Marking QoS flow IDs in both DL and UL packets

[0164] - Mapping the reflected QoS flow to the DRB for UL SDAP PDUs.

[0165] For an SDAP layer device, the UE may receive configuration regarding whether to use the header of the SDAP layer device or the function of the SDAP layer device as an RRC message configuration for each PDCP layer device, for each bearer, or for each logical channel. When configuring the SDAP header, the UE may be instructed to update or reconfigure the QoS flows for UL and DL and the mapping information on the DRB through the NAS-reflected QoS configuration 1-bit indicator and the AS-reflected QoS configuration 1-bit indicator of the SDAP header. The SDAP header may include QoS flow ID information indicating QoS. The QoS information may be used as data processing priorities, scheduling information, etc. for smoothly supporting services.

[0166] The main functions of NR PDCP 9-30 and 9-65 may include some of the following functions.

[0167] - Header compression and decompression: Only ROHC

[0168] - User data transfer

[0169] - In-sequence delivery of upper layer PDUs

[0170] - Out-of-sequence delivery of upper layer PDUs

[0171] - PDCP PDU reordering for reception

[0172] - Duplicate detection of lower layer SDUs

[0173] - Retransmission of PDCP SDUs

[0174] - Encryption and decryption

[0175] - Timer-based SDU discard in the uplink

[0176] The reordering of the above NR PDCP device refers to the function of reordering the PDCP PDUs received from the lower layer based on the PDCP sequence number (SN), and may include delivering data to the upper layer in the reordered order. Alternatively, the reordering may include the function of delivering data immediately regardless of the order, the function of recording the lost PDCP PDUs by recording the order, the function of sending a status report of the lost PDCP PDUs to the transmission side, and the function of requesting retransmission of the lost PDCP PDUs.

[0177] The main functions of NR RLC 9-35 and 9-60 may include some of the following functions.

[0178] - Upper layer PDU transmission

[0179] - In-sequence delivery of upper layer PDUs

[0180] - Out-of-order transfer of upper-layer PDUs

[0181] - Error correction via ARQ

[0182] - Concatenation, segmentation, and reassembly of RLC SDUs

[0183] - Resegmentation of RLC data PDUs

[0184] - Reordering of RLC data PDUs

[0185] - Duplicate detection

[0186] - Protocol error detection

[0187] - RLC SDU discard

[0188] - RLC re-establishment

[0189] In-sequence transfer of the NR RLC device refers to the function of transferring RLC SDUs received from the lower layer to the higher layer in sequence. If the original RLC SDU is segmented into multiple RLC SDUs and received, in-sequence transfer may include the functions of reassembling and transferring the segmented RLC SDUs, rearranging the received RLC PDUs based on the RLC sequence number (PD) SN or PDCP sequence number (SN), reordering to record lost RLC PDUs, sending a status report of the lost RLC PDUs to the transmission side, and requesting retransmission of the lost RLC PDUs. If there are lost RLC SDUs, in-sequence transfer of the NR RLC device may include the function of transferring only the RLC SDUs that depend on the lost RLC SDUs to the higher layer. Or, if the predetermined timer has expired even though there are lost RLC SDUs, in-sequence transfer may include the function of transferring all RLC SDUs received before the timer started to the higher layer in sequence, or if the predetermined timer has expired even though there are lost RLC SDUs, in-sequence transfer may include the function of transferring all RLC SDUs received so far to the higher layer in sequence. In addition, RLC PDUs can be processed in the order they are received (in the order of the sequence numbers, regardless of the order of the sequence numbers, or in the order of arrival), and can be transferred to the PDCP device in out-of-order transfer. Or, in the case of segments, segments that can be received and stored in the buffer or will be received later can be reconfigured into complete RLC PDUs, processed, and transferred to the PDCP device. The NR RLC layer may not include the concatenation function, and the above functions can be executed in the NR MAC layer, or the corresponding functions can be replaced by the multiplexing function of the NR MAC layer.

[0190] The unordered transfer of the NR RLC device refers to the function of immediately transferring the RLC SDU received from the lower layer to the higher layer regardless of the order. If the original RLC SDU is segmented into multiple RLC SDUs and received, the unordered transfer may include the functions of reassembling and transferring the segmented RLC SDUs, as well as storing and reordering the RLC SN or PDCP SN of the received RLC PDUs to record the lost RLC PDUs.

[0191] NR MAC 9-40 and 9-55 can be connected to several NR RLC layer devices configured in a UE, and the main functions of the NR MAC may include some of the following functions.

[0192] - Mapping between logical channels and transport channels

[0193] - Multiplexing / demultiplexing of MAC SDUs

[0194] - Reporting scheduling information

[0195] - Error correction via HARQ

[0196] - Prioritization between logical channels of a UE

[0197] - Prioritization between UEs via dynamic scheduling

[0198] - MBMS service identification

[0199] - Transmission format selection

[0200] - Padding

[0201] The NR PHY layers 9-45 and 9-50 can perform channel coding and modulation on the higher layer data, convert it into OFDM symbols, and send the OFDM symbols to the wireless channel. Additionally, the NR PHY layers 9-45 and 9-50 can demodulate and channel decode the OFDM symbols received through the wireless channel, and send the decoded data to the higher layer.

[0202] The detailed structure of the radio protocol architecture can be changed in various ways according to the carrier (or cell) operation method. For example, when the eNB sends data to the UE based on a single carrier (or cell), the eNB and the UE use a protocol architecture with a single structure for each layer as in 9-00. On the other hand, when the eNB sends data to the UE from a single TRP using multiple carriers based on carrier aggregation (CA), the eNB and the UE may have a single structure depending on the RLC, but may use a protocol architecture for multiplexing the PHY layer through the MAC layer as in 9-10. As another example, when the eNB sends data to the UE from multiple TRPs using multiple carriers based on dual connectivity (DC), as in 9-20, the eNB and the UE may have a single structure depending on the RLC, but may use a protocol architecture for multiplexing the PHY layer through the MAC layer.

[0203] In LTE and NR, the UE has a procedure to report the capabilities supported by the UE to the corresponding eNB when connected to the serving eNB. In the following description, this is referred to as UE capabilities (report). The eNB may send a UE capabilities query message requesting a capabilities report to the UE in the connected state. This message may include a UE capabilities request for each RAT type. The request for each RAT type may include the requested band information. In addition, the UE capabilities query message may request multiple RAT types from one RRC message container, or may include a UE capabilities query message that includes multiple requests for each RAT type, and may send the message to the UE. That is, the UE capabilities query may be repeated multiple times, and the UE may configure the corresponding UE capabilities information message multiple times and may report the configured message multiple times. In the next-generation telecommunication system, a UE capabilities request for MR-DC (including NR, LTE, EN-DC, etc.) may be made. For reference, the UE capabilities query message is typically sent initially after the UE is connected, but may be requested under any condition when the eNB requires it.

[0204] In the above steps, the UE that receives the UE capabilities report request from the eNB configures the UE capabilities according to the RAT type and band information requested by the eNB. Below, an overview of the method for the UE to configure UE capabilities in the NR system is shown.

[0205] 1. If the UE receives an LTE and / or NR band list from the eNB as a UE capabilities request, the UE configures a band combination (BC) for EN-DC and NR standalone (SA). That is, based on the bands requested as FreqBandList, a candidate list of BCs for EN-DC and NR SA is configured in the eNB. In addition, the bands have priorities in the order described in the FreqBandList.

[0206] 2. If the eNB requests UE capability reporting by setting the "eutra-nr-only" flag or the "eutra" flag, the UE completely removes the NR SA BC from the candidate list of the configured BC. This operation can only be performed when the LTE eNB requests "eutra" capabilities.

[0207] 3. Thereafter, the UE removes the fallback BC from the candidate list of the BC configured in the above step. Here, the fallback BC corresponds to the case of removing the band corresponding to at least one SCell from any superset BC, and since the superset BC may already cover the fallback BC, the fallback BC can be omitted. This step also applies to MR-DC, i.e., the LTE band. The BC remaining after this step is the final "candidate BC list".

[0208] 4. The UE selects the BC to report by selecting the BC corresponding to the requested RAT type from the final "candidate BC list". In this step, the UE configures the supportedBandCombinationList in a predetermined order. That is, the UE configures the BC and UE capabilities to be reported in the order of the predetermined rat-Type (nr -> eutra-nr -> eutra). The UE also configures the feature set combination for the supportedBandCombinationList and configures a list of "candidate feature set combinations" from the candidate BC list, and deletes the list for the fallback BC (including equal or lower-level capabilities) from the candidate BC list. The "candidate feature set combinations" include the feature set combinations of NR and EUTRA-NR BCs and can be obtained from the feature set combinations of the UE-MRDC-Capabilities and UE-NR-Capabilities containers.

[0209] 5. In addition, if the requested rat-Type is eutra-nr and affected, the feature set combination is included in both containers, i.e., UE-MRDC-Capabilities and UE-NR-Capabilities. However, the feature set of NR is only included in UE-NR-Capabilities.

[0210] After configuring the UE capabilities, the UE transmits a UE capability information message including the UE capabilities to the eNB. The eNB then performs appropriate scheduling and transmit / receive management on the UE based on the UE capabilities received from the UE.

[0211] Referring to the description of the PDSCH transmission / reception process (such as DCI structure, PDSCH time / frequency resource allocation, radio protocol structure, etc.), in Release 15, NR focuses on allocating the PDSCH transmitted from a single transmission point. In the case of cooperative communication where a UE receives the PDSCH transmitted from multiple points, additional standard support is required. For example, since the control information includes one piece of frequency-domain and time-domain resource allocation information corresponding to one PDSCH, a method for extending or processing the above information to allocate two or more PDSCHs is needed.

[0212] According to the present disclosure, a time and frequency resource allocation method for effectively allocating multiple PDSCHs to a UE can be provided to improve the efficiency of cooperative communication.

[0213] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In addition, when determining that the detailed description of relevant functions or configurations may unnecessarily obscure the subject matter of the present disclosure, the detailed description thereof will be omitted. The terms to be described later are terms defined in consideration of the functions in the present disclosure and may be changed according to the intention or habit of the user or operator. Therefore, the definitions should be based on the content throughout the specification.

[0214] Hereinafter, the base station is the entity that performs resource allocation for the terminal and may be at least one of a gNode B, gNB, eNodeB, Node B, base station (BS), radio access unit, base station controller, or a node on the network. The terminal may include a user equipment (UE), mobile station (MS), cellular phone, smart phone, computer, or a multimedia system capable of performing communication functions. In addition, hereinafter, the embodiments of the present disclosure will be described using the NR or LTE / LTE-A system as an example, but the embodiments of the present disclosure may be applied to other communication systems having a similar technical background or channel form. In addition, the embodiments of the present disclosure may be applied to other communication systems with some modifications within the scope of the present disclosure without departing from the judgment of those skilled in the art.

[0215] The content of the present disclosure can be applied to FDD and TDD systems.

[0216] Hereinafter, in the present disclosure, higher signaling is a signal transmission method in which data is transmitted from the eNB to the UE using the downlink data channel of the physical layer, or data is transmitted from the UE to the eNB using the uplink data channel of the physical layer, and the higher signaling may be referred to as RRC signaling, PDCP signaling, or MAC CE.

[0217] In the following, in the present disclosure, when determining whether to apply cooperative communication, the UE may use various methods, such as a method in which the PDCCH for allocating the PDSCH to which cooperative communication is applied has a specific format, a method in which the PDCCH for allocating the PDSCH to which cooperative communication is applied includes a specific indicator for notifying whether cooperative communication is applied, a method in which the PDCCH for allocating the PDSCH to which cooperative communication is applied is scrambled with a specific RNTI, or a method in which it is assumed that cooperative communication is applied in a specific part indicated by a higher layer. In the following, for ease of description, based on conditions similar to the above, the case where the UE receives the PDSCH to which cooperative communication is applied will be referred to as the NC-JT case.

[0218] In the following, in the present disclosure, determining the priority between A and B means selecting one with a higher priority according to a predetermined priority rule to perform the corresponding operation, or omitting (or discarding) the operation for the other with a lower priority.

[0219] In the following description of the present disclosure, the above examples will be described through multiple embodiments, but these examples are not independent, and one or more embodiments can be applied simultaneously or in combination.

[0220] <First Embodiment: Multiple DCI Receiving for NC-JT>

[0221] Different from existing wireless communication systems, the 5G wireless communication system can support not only services requiring high transmission speeds, but also services with very short transmission delays and services requiring high connection densities. In a wireless communication network including multiple cells, transmission and reception points (TRPs), or beams, cooperative communication (cooperative transmission) between each cell, TRP, and / or beam is one of the technologies capable of increasing the strength of the signal received by the UE or effectively performing interference control between each cell, TRP, and / or beam to meet the above various service requirements.

[0222] Joint transmission (JT) is a representative transmission technology for cooperative communication, and cooperative communication can support using one UE with different cells, TRPs, and / or beams through the above technologies to increase the strength of the signal received by the UE. On the other hand, since the channels between each cell, TRP, and / or beam and the UE may have very different characteristics, it is necessary to apply different precoding, MCS, resource allocation, etc. to the links between each cell, TRP, and / or beam and the UE. Specifically, in the case of non-coherent joint transmission (NC-JT) that supports non-interfering precoding between each cell, TRP, and / or beam, the configuration of separate DL transmission information for each cell, TRP, and / or beam becomes important. At the same time, such a configuration of separate DL transmission information for each cell, TRP, and / or beam is a major factor in increasing the payload required for DL DCI transmission, which adversely affects the reception performance of the physical downlink control channel (PDCCH) used to transmit DCI. Therefore, it is necessary to carefully design the trade-off between the DCI information amount and the PDCCH reception performance for JT support.

[0223] Figure 10 A diagram showing a JT technique according to an embodiment of the present disclosure and an example of radio resource allocation for each TRP according to the situation.

[0224] In Figure 10 FIG. 10-00 shows a diagram of coherent joint transmission (C-JT) that supports interfering precoding between each cell, TRP, and / or beam. In C-JT, the same data (PDSCH) is transmitted in TRP A 10-05 and TRP B 10-10, and joint precoding is performed in multiple TRPs. This means that the same DMRS ports for the same PDSCH reception are transmitted in TRP A 10-05 and TRP B 10-10 (for example, DMRS ports A and B in the two TRPs). In this case, the UE will receive one DCI message for receiving one PDSCH demodulated by DMRS ports A and B.

[0225] In Figure 10Among them, FIGS. 10-20 show diagrams of non-coherent joint transmission (NC-JT) that supports non-interfering precoding between each cell, TRP, and / or beam. In NC-JT, different PDSCHs are transmitted in each cell, TRP, and / or beam, and separate precoding can be applied to each PDSCH. This means that different DMRS ports for different PDSCH receptions are transmitted in TRP A 10-25 and TRP B 10-30 (for example, DMRS port A in TRP A and DMRS port B in TRP B). In this case, the UE will receive two types of DCI information for receiving PDSCH A demodulated by DMRS port A and PDSCH B demodulated by another DMRS port B.

[0226] For example, in the case of NC-JT, various wireless resource allocations can be considered in cases where the frequency and time resources used by multiple TRPs are the same according to Figure 10 (10-40), the frequency and time resources used by multiple TRPs do not overlap with each other at all (10-45), or some of the frequency and time resources used by multiple TRPs overlap with each other (10-50). In particular, in the case of 10-50, it can be seen that the DCI payload required for resource allocation information increases linearly with the number of TRPs. This increase in the DL DCI payload may adversely affect the reception performance of the PDCCH used to transmit the DCI, or may significantly increase the DCI blind decoding complexity of the UE as described above. Therefore, the present disclosure provides a method for PDSCH time and frequency resource allocation to effectively support NC-JT.

[0227] Various forms, structures, and relationships of DCI can be considered to simultaneously allocate multiple PDSCHs to a UE for NC-JT support.

[0228] Figure 11 Diagrams showing four examples of DCI designs for NC-JT support according to embodiments of the present disclosure are shown.

[0229] In Figure 11In Case #1 11-00, an example is shown where, when different (N-1) PDSCHs are transmitted in (N-1) additional TRPs (TRP#1 to TRP#(N-1)) other than the serving TRP (TRP#0) used when transmitting a single PDSCH, the control information for the PDSCH transmitted in the additional TRPs is transmitted in the same DCI format as the control information for the PDSCH transmitted in the serving TRP. That is, the UE obtains the control information for the PDSCHs transmitted in different TRPs (TRP#0 to TRP#(N-1)) through DCIs (DCI#0 to DCI#(N-1)) that all have the same DCI format and the same payload. The advantage of Case #1 is that the degree of freedom of each PDSCH control (allocation) is fully guaranteed. However, when each DCI is transmitted in a different TRP, poor coverage of each DCI may occur, thus reducing the reception performance.

[0230] In Figure 11 In Case #2 11-05, an example is shown where, when different (N-1) PDSCHs are transmitted in (N-1) additional TRPs (TRP#1 to TRP#(N-1)) other than the serving TRP (TRP#0) used when transmitting a single PDSCH, the control information for the PDSCH transmitted in the additional TRPs is transmitted in a different DCI format or with a different DCI payload from the control information for the PDSCH transmitted in the serving TRP. In the case of DCI#0 that transmits the control information for the PDSCH transmitted in the serving TRP (TRP#0), DCI#0 includes all the information elements of DCI format 1_0 into DCI format 1_1. However, in the case where "shortened" DCIs (sDCI#0 to sDCI#(N-2)) transmit the control information for the PDSCHs transmitted in the cooperating TRPs (TRP#1 to TRP#(N-1)), the "shortened" DCIs may only include some of the information elements from DCI format 1_0 to DCI format 1_1. Therefore, in the case where sDCI transmits the control information for the PDSCHs transmitted in the cooperating TRPs, the sDCI may have a smaller payload compared to the normal DCI (nDCI) that transmits the relevant control information for the PDSCH transmitted in the serving TRP, or may include reserved bits with a reduced number of lost bits compared to the nDCI. The disadvantage of Case #2 is that the degree of freedom of each PDSCH control (allocation) can be restricted according to the content of the information elements included in the sDCI. However, since the reception performance of the sDCI is better than that of the nDCI, there is an advantage of reducing the occurrence probability of poor coverage of each DCI.

[0231] In Figure 11In case #3 1-10, another example is shown in which, in the case where different (N-1) PDSCHs are transmitted in (N-1) additional TRPs (TRP#1 to TRP#(N-1)) other than the serving TRP (TRP#0) used when transmitting a single PDSCH, the control information for the PDSCH transmitted in the additional TRPs is transmitted in a different DCI format or a different DCI payload from the control information for the PDSCH transmitted in the serving TRP. For example, in the case of DCI#0 that transmits the control information for the PDSCH transmitted in the serving TRP (TRP#0), DCI#0 includes all information elements of DCI format 1_0 into DCI format 1_1. In the case of the control information for the PDSCH transmitted in the cooperating TRPs (TRP#1 to TRP#(N-1)), only some information elements from DCI format 1_0 to DCI format 1_1 can be collected in a "secondary" DCI (sDCI) and transmitted. For example, the sDCI can have at least one HARQ-related information such as frequency domain resource allocation, time domain resource allocation, MCS, etc. of the cooperating TRPs. In addition, in the case where information such as a BWP indicator or a carrier indicator is not included in the sDCI, the DCI (DCI#0, normal DCI or nDCI) of the serving TRP can be followed. The disadvantage of case #3 is that the degree of freedom of each PDSCH control (allocation) can be restricted according to the content of the information elements included in the sDCI, but the advantage is that the reception performance of the sDCI can be adjusted, and compared with case #1 or case #2, the DCI blind decoding complexity of the UE can be reduced.

[0232] In Figure 11 In case #4 11-15, another example is shown in which, in the case where different (N-1) PDSCHs other than the serving TRP (TRP#0) used when transmitting a single PDSCH are transmitted in (N-1) additional TRPs (TRP#1 to TRP#(N-1)), the control information for the PDSCH transmitted in the additional TRPs is transmitted in a DCI (long DCI (1DCI)) in the same way as the control information for the PDSCH transmitted in the serving TRP. That is, the UE obtains the control information for the PDSCHs transmitted in different TRPs (TRP#0 to TRP#(N-1)) through a single DCI. The advantage of case #4 is that it does not increase the DCI blind decoding complexity of the UE, but the disadvantage is that it reduces the degree of freedom of PDSCH control (allocation), for example, due to the limited number of cooperating TRPs caused by the long DCI payload limitation.

[0233] In the following description and embodiments, sDCI may refer to various secondary DCIs included in PDSCH control information transmitted in a cooperative TRP, such as shortened DCI, secondary DCI, or normal DCI (DCI formats 1_0 to 1_1 as described above). Here, if no specific restriction is specified, this description equally applies to various auxiliary DCIs.

[0234] In the following description and embodiments, cases #1, #2, and #3 in which one or more DCIs (PDCCHs) are used to support NC-JT are classified as NC-JT based on multiple PDCCHs. Case #4 in which a single DCI (PDCCH) is used to support NC-JT is classified as NC-JT based on a single PDCCH.

[0235] The following description and embodiments provide a detailed allocation method for time and frequency resources for NC-JT based on multiple PDCCHs and NC-JT based on a single PDCCH.

[0236] In an embodiment of the present disclosure, in practical applications, "cooperative TRP" may be replaced by various terms such as "cooperative panel" or "cooperative beam".

[0237] In an embodiment of the present disclosure, "when applying NC-JT" can be interpreted in various ways according to situations such as "when a UE simultaneously receives one or more PDSCHs in a BWP", "when a UE simultaneously receives PDSCHs indicated by two or more TCIs in a BWP", "when the PDSCH received by a UE is associated with one or more DMRS port groups", etc. However, for the convenience of description, it is used as an expression.

[0238] In the present disclosure, the radio protocol structure for NC-JT can be used in various ways according to the TRP deployment situation. For example, if there is no backhaul delay between cooperative TRPs or there is a small backhaul delay between them, a structure based on MAC layer multiplexing similar to Figure 9 9-10 (CA-like method) can be used. On the other hand, if the backhaul delay between cooperative TRPs is large and cannot be ignored (for example, if CSI exchange or scheduling information exchange between cooperative TRPs requires 2 ms or more), an independent structure for each TRP starting from the RLC layer as in Figure 9 9-20 (DC-like method) can be used to ensure latency-robust characteristics.

[0239] <Second Embodiment: FD-RA for NC-JT>

[0240] In this embodiment, a method for frequency-domain resource allocation (FD-RA) considering NC-JT will be described.

[0241] According to the above description, the number of bits for a traditional single PDSCH FD-RA may require 15 bits or more of payload depending on the number of PRBs in the BWP. When simply expanding the number of bits of a traditional single PDSCH FD-RA, the number of FD-RA payloads required when allocating N>1 PDSCHs for NC-JT may be 15*N bits or more, which may become a heavy load on DCI transmission.

[0242] To solve this problem, when using the same FD-RA payload as in Release 15 NR in a PDCCH, the following method can be used:

[0243] Method 1: In the case where type 0 indicates whether corresponding frequency band resources are allocated to a predetermined resource block group (RBG) through a bitmap, it is possible to promise to change the size of the RBG according to the number of PDSCHs allocated by the corresponding PDCCH. The number of PDSCHs allocated by the corresponding PDCCH can be indicated to the UE by various methods, such as explicitly indicating through a specific field value in the DCI sent by the corresponding PDCCH, or implicitly determining based on the number or status of TCI states or QCL information in the DCI sent by the corresponding PDCCH (for example, according to how many QCL information are included / indicated).

[0244] [Table 7]

[0245]

[0246]

[0247] Table 7 shows an example of a method for determining the RBG size according to the number of PRBs included in the BWP through UE capability signaling of the UE and higher layer configuration of the eNB when the maximum number of PDSCHs allocated by one PDCCH for the UE is 2. Referring to Table 7, when the number of PDSCHs allocated by any DCI is determined to be 1 (Condition A) through the above conditions or methods, one of {2, 4, 8, 16} or {4, 8, 16, 16} is used according to the higher layer configuration (Configuration 1 or Configuration 2) of the eNB. On the other hand, if the number of PDSCHs allocated by any DCI is determined to be 2 (Condition B) through the above conditions or methods, the RBG size is doubled compared to the single PDSCH case according to the higher layer configuration (Configuration 1 or Configuration 2) of the eNB, so that one of {4, 8, 16, 32} or {8, 16, 32, 32} is used. In this way, FD-RA can be performed on up to two PDSCHs without increasing the traditional FD-RA payload. Even if any DCI can allocate three or more PDSCHs, the above method can be similarly extended. In this method, all FD-RA bits are divided into subgroups according to the number of allocated PDSCHs, and all FD-RA bits can be mapped to each PDSCH according to the signaling order of the TCI state (or QCL information) in the corresponding DCI.

[0248] ● Method 1-1: For the RBG, a fixed TRP allocation for each RBG can be assumed. For example, in the resource allocation of n RBGs in the BWP, such as RBG0,..., RBG n-1 , even-numbered RBGs (e.g., RBG0, RBG2,...) can be designated for use in TRP0, while odd-numbered RBGs (e.g., RBG1, RBG3,...) can be designated for use in TRP1. Which RBG in the RBG is allocated to the UE can be indicated by the RBG bitmap in the above DCI, and the corresponding RBG bitmap size can be equal to the RBG bitmap size of Release 15 NR. An example of the relationship between the RBG and the TRP and the bitmap for RBG allocation is shown in Figure 18 . Even if any DCI can allocate three or more PDSCHs, the above method can be similarly extended.

[0249] If a larger FD-RA payload than Release 15 NR is used in one PDCCH, the following method can be used:

[0250] ● Method 2: For FD-RA type 0 or type 1, it is possible to change the FD-RA payload size according to the number of PDSCHs allocated by the corresponding PDCCH. The number of PDSCHs allocated by the corresponding PDCCH can be indicated to the UE by various methods, such as explicitly indicated by a specific field value in the DCI sent by the corresponding PDCCH or implicitly determined based on the number or status of TCI states or QCL information in the DCI sent by the corresponding PDCCH (e.g., according to how many QCL information are included / indicated). In this method, the RBG size depending on the number of PRBs included in the BWP is used in the same way as in the prior art, and different FD-RAs are performed on different PDSCHs by linearly increasing the FD-RA payload according to the maximum number of PDSCHs that can be allocated to the UE by one PDCCH through UE capability signaling of the UE and higher layer configuration of the eNB. In this case, the entire FD-RA bits are divided into subgroups according to the number of allocated PDSCHs, and can be mapped to each PDSCH according to the signaling order of the TCI state (or QCL information) in the corresponding DCI.

[0251] ● Method 3: In the case of type 0 indicating whether resources are allocated to the corresponding frequency band by a bitmap for a predetermined resource block group (RBG), an additional RBG configuration can be selected according to the number of PDSCHs allocated by the corresponding PDCCH. The number of PDSCHs allocated by the corresponding PDCCH can be indicated to the UE by various methods, such as explicitly indicated by a specific field value in the DCI sent by the corresponding PDCCH, or implicitly determined based on the number or status of TCI states or QCL information in the DCI sent by the corresponding PDCCH (e.g., according to how many QCL information are included / indicated).

[0252] [Table 8]

[0253]

[0254] Table 8 shows an example of a method for determining the RBG size according to the number of PRBs included in a BWP through UE capability signaling and higher layer configuration of the eNB when the maximum number of PDSCHs that can be allocated by one PDSCH allocation for a UE is two or more. Referring to Table 8, when the number of PDSCHs allocated by any DCI is determined to be 1 (Condition A) through the above conditions or methods, one of {2, 4, 8, 16} or {4, 8, 16, 16} is used according to the higher layer configuration (Configuration 1 or Configuration 2) of the eNB. On the other hand, if the number of PDSCHs allocated by any DCI is determined to be 2 (Condition B) through the above conditions or methods, one of the newly determined RBG sizes (in this example, {4, 8, 16, 32},...) is used according to the higher layer configuration (Configuration 3 or Configuration 4 or...) of the eNB. In this way, FD-RA can be performed on two or more PDSCHs while appropriately increasing the traditional FD-RA payload. In this method, all FD-RA bits are divided into subgroups according to the number of allocated PDSCHs, and all FD-RA bits can be mapped to each PDSCH according to the signaling order of the TCI state (or QCL information) in the corresponding DCI.

[0255] ● Method 4: In the case of Type 1 where resource allocation information is notified by the start position of the VRB and the allocated VRB length, the FD-RA payload for multiple PDSCHs can be reduced by introducing stepwise FD-RA. Figure 12 A diagram showing an example of stepwise FD-RA according to an embodiment of the present disclosure is shown. Referring to Figure 12 , FD-RA methods with different steps can be selected according to the number of PDSCHs allocated by the corresponding PDCCH. The number of PDSCHs allocated by the corresponding PDCCH can be indicated to the UE by various methods, such as explicitly indicated by a specific field value in the DCI sent by the corresponding PDCCH, or implicitly determined based on the number or status of the TCI state or QCL information in the DCI sent by the corresponding PDCCH (for example, according to how many pieces of QCL information are included / indicated). Referring to Figure 12, when the number of PDSCHs allocated by the corresponding PDCCH is 1, the frequency resources can be allocated in a single step by FD-RA12-00. On the other hand, if there are two or more PDSCHs allocated by the corresponding PDCCH, the frequency resources can be allocated by FD-RA12-05 with two steps. In the two-step FD-RA12-05, the first step 12-10 indicates joint information about the frequency-domain resources occupied by multiple PDSCHs based on the starting VRB and the length. In the two-step FD-RA12-05, the second step 12-15 indicates information about each of the frequency-domain resources occupied by multiple PDSCHs sequentially based on the starting VRB and the length. At this time, the payload required in each step is the same as Equation 1 in the first step 12-10 and the same as Equation 2 in the second step. In Equation 1, represents the number of PRBs in the BWP indicated by the DCI within the corresponding PDCCH. In Equation 2, represents the VRB length indicated in the first step 12-10, and N represents the number of PDSCHs allocated by the corresponding DCI. In Figure 12 , the VRB is shown as being composed of consecutive PRBs, but this is for ease of description, and it should be noted that the mapping to the actual PRBs can be changed differently according to a predetermined rule.

[0256] [Equation 1]

[0257]

[0258] [Equation 2]

[0259]

[0260] The methods 1 to 4 according to this embodiment are not mutually exclusive and can be cross-supported according to conditions. For example, it can be promised to use Method 1 for FD-RA type 0 and Method 4 for FD-RA type 1. Various other combinations are also possible, but in order not to obscure the key points of the explanation, not all possibilities are listed.

[0261] In the case of type 1 in which resource allocation information is notified by the start position of the VRB and the allocated VRB length, the FD-RA payload has been compressed in the form of an index and length combination indicating the start position of the available VRB, making it significantly difficult to include additional information while maintaining the regular FD-RA payload. Therefore, the UE may have DCI indicating NC-JT operation, that is, allocating one or more PDSCHs to at least one or more identical OFDM symbols, which may have the same FD-RA payload as the FD-RA payload of Release 15 NR, and when using FD-RA type 1, it can be committed to understanding that the corresponding DCI allocates the same FD-RA to all one or more PDSCHs.

[0262] <Third Embodiment: TD-RA for NC-JT>

[0263] In this embodiment, a time-domain resource allocation (TD-RA) method considering NC-JT will be described.

[0264] According to the above description, depending on the configuration, the number of bits for conventional single PDSCH TD-RA can be from 0 to 4 bits, and if the number of bits is simply extended, the number of FD-RA payloads required when N > 1 PDSCHs are allocated for NC-JT can be 4*N or more. Compared with FD-RA, this is not a large increase, but TD-RA needs to be carefully designed because it is intertwined with various issues such as DMRS RE pattern, PDCCH monitoring occasion, PDSCH RE mapping, channel estimation, control channel load balancing, etc.

[0265] Considering the above problems, it is possible to use at least one of the following three methods for the SLIV and PDSCH mapping types among the information included in TD-RA.

[0266] ● Method 1: In this method, when the UE simultaneously receives two or more PDSCHs sharing at least some time and frequency resources, in order to reduce the implementation complexity of interference management including interference measurement and interference cancellation between two or more PDSCHs, match the SLIV and PDSCH mapping types of the two or more PDSCHs. In this case, since the same RE pattern can be guaranteed for all simultaneously received PDSCHs for the UE, the NC-JT reception operation including interference management is simplified. At this time, in order to ensure the simplicity of the UE's implementation complexity, "when two or more PDSCHs sharing at least some time and frequency resources are assigned different SLIV values or different PDSCH mapping type values, do not receive all PDSCHs", or "when two or more PDSCHs sharing at least some time and frequency resources are assigned different SLIV values or different PDSCH mapping type values, it can be committed to receive only the PDSCH with the highest priority among the PDSCHs". In this case, the priority between PDSCHs can be determined by various methods, such as the PDSCH with the smallest k0 value, the PDSCH with the smallest TCI state ID, or the PDSCH with the smallest HARQ process ID.

[0267] ● Method 2: In this method, when the UE simultaneously receives two or more PDSCHs sharing at least some time and frequency resources, in order to reduce the UE implementation complexity and allocate the PDCCH transmission load of the eNB (PDCCH load balancing), match the SLIV values of the two or more PDSCHs, but the PDSCH mapping types can be allowed to have different values. Figure 13 A diagram showing the PDCCH monitoring opportunity according to the PDSCH mapping type according to an embodiment of the present disclosure is shown. Refer to Figure 13, in the case of PDSCH mapping type A, only the first third OFDM symbol in a time slot can be designated as a PDCCH monitoring occasion (13-00), while in the case of PDSCH mapping type B, all OFDM symbols in a time slot can be designated as a PDCCH monitoring occasion (13-05). This means that the PDSCH mapping type of the NC-JT PDSCH can be appropriately allocated according to the network traffic load, thereby preventing PDCCH transmissions from being aggregated in some symbols of a time slot. This method is particularly applicable to multi-PDCCH-based NC-JT that requires two or more PDCCH transmissions for NC-JT allocation. In this case, to ensure the implementation complexity of the UE, "when two or more PDSCHs sharing at least some time and frequency resources are allocated with different SLIV values, do not receive all PDSCHs", or "when two or more PDSCHs sharing at least some time and frequency resources are allocated with different SLIV values, it can be committed to only receive the PDSCH with the highest priority among the PDSCHs". In this case, the priority between PDSCHs can be determined by various methods, such as the PDSCH with the minimum k0 value, the PDSCH with the minimum TCI state ID, or the PDSCH with the minimum HARQ process ID.

[0268] ● Method 3: In this method, when the UE simultaneously receives two or more PDSCHs sharing at least some time and frequency resources, in order to maximize the degree of scheduling freedom and throughput performance, there are no restrictions on the SLIV values and PDSCH mapping types for the two or more PDSCHs. In this case, the DMRS RE patterns in the two or more PDSCHs may not match, and the DMRS channel estimation performance may deteriorate due to the conflict between the DMRS REs of one PDSCH and the PDSCH REs of another PDSCH. To solve this problem, if the SLIV values or PDSCH mapping types of the two or more PDSCHs are different, it is necessary to perform rate matching on the PDSCH REs located in the DMRS REs of other PDSCHs. For this purpose, if the SLIV values or PDSCH mapping types of the two or more PDSCHs are different, the UE may "receive an additional SLIV value and perform PDSCH RE rate matching at the DMRS RE positions determined by associating the additional SLIV value with a conventional DMRS port and CDM group without data indication information", or "perform PDSCH RE rate matching at the DMRS RE positions determined by associating a pair of additional DMRS port number indication information with the additional SLIV value", or "perform PDSCH RE rate matching based on signaling that notifies whether symbol-by-symbol PDSCH RE rate matching is applied", or "perform PDSCH RE rate matching based on the RE-level rate matching signal of Release 15 NR", whereby when performing DMRS channel estimation for NC-JT PDSCH demodulation, it is possible to ensure that no additional operations (e.g., PDSCH interference cancellation (successive interference cancellation) in DMRS REs) are performed.

[0269] Considering the above problems, it is possible to use at least one of the following two methods for k0 of the information included in TD-RA.

[0270] ● Method 4: In this method, when the UE receives two or more PDSCHs that share at least some time and frequency resources simultaneously, to reduce the implementation complexity of the PDSCH discard rule and processing time management for preparing the reception of two or more PDSCHs, all k0 values of the two or more PDSCHs are matched. In this case, since the same processing time can be guaranteed for all PDSCHs received simultaneously by the UE, the pipeline management for NC-JT PDSCH reception is simplified. In this case, to ensure the simplicity of the UE's implementation complexity, for example, if the k0 values of all PDSCHs are the same, up to 2 (or >2 per UE capability signaling) PDSCHs can be allocated to the UE with NC-JT capability on the same OFDM symbol. Otherwise, the UE can assume that the PDSCH with the minimum k0 value is only allocated on the OFDM symbol that can be committed. Figure 14 A diagram showing a brief example of the above description, and a diagram showing a method for monitoring two or more PDSCHs according to an embodiment of the present disclosure. Refer to Figure 14 , in the case where two different PDSCHs share at least partially the same time and frequency resources, if the k0 values of the two PDSCHs are different, the UE regards it as a single TRP transmission and performs the corresponding operations at 14-00 (e.g., only receives one PDSCH with the highest priority). On the other hand, in the case where two allocated different PDSCHs share at least partially the same time and frequency resources, if the k0 values of the two PDSCHs are the same, the UE regards it as an NC-JT transmission and performs the corresponding operations at 14-05 (e.g., receives all corresponding PDSCHs).

[0271] ● Method 5: In this method, when the UE simultaneously receives two or more PDSCHs that share at least some time and frequency resources, in order to reduce the implementation complexity of the processing time management for preparing the reception of two or more PDSCHs and the PDSCH discard rule, all k0 values of the two or more PDSCHs are matched. A threshold can be set on the difference between the k0 values of the two or more PDSCHs. One or more thresholds can be predetermined, but can be known to the UE through higher layer signaling. That is, if two or more PDSCHs that share some time and frequency resources are allocated by DCI sent within a given time interval, the UE determines it as NC-JT. In this case, in order to ensure the simplicity of the UE's implementation complexity, for example, it can be promised that "if the value of |maxk0 - mink0| for all PDSCHs is less than a given threshold, a UE with NC-JT capability can be allocated up to 2 (or more than 2) PDSCHs on the same OFDM symbol". Otherwise, the UE can assume that only the PDSCH with the minimum k0 value is allocated on this OFDM symbol. Specifically, in the case where two different PDSCHs share at least partially the same time and frequency resources, if the difference between the k0 values of the two PDSCHs is greater than the threshold, the UE regards it as a single TRP transmission and performs the corresponding operation (for example, only receives one PDSCH with the highest priority). On the other hand, in the case where two allocated different PDSCHs share at least partially the same time and frequency resources, if the difference between the k0 values of the two PDSCHs is less than the threshold, the UE regards it as an NC-JT transmission and performs the corresponding operation (for example, receives all corresponding PDSCHs).

[0272] ● Method 6: In this method, when the UE simultaneously receives two or more PDSCHs that share at least some time and frequency resources, in order to reduce the implementation complexity of the processing time management for preparing the reception of two or more PDSCHs and the PDSCH discard rule, it can be determined whether to apply NC-JT based on the HARQ process ID values of the two or more PDSCHs. As an example, Figure 15 FIG. shows another example of a diagram illustrating a method of monitoring two or more PDSCHs according to an embodiment of the present disclosure. Referring to Figure 15 , when two or more PDSCHs sharing a certain time and frequency resource are allocated to have the same HARQ process ID, the UE regards it as an NC-JT transmission and performs the corresponding operation (for example, receives all corresponding PDSCHs). On the other hand, when two or more PDSCHs are allocated to have different HARQ process IDs, the UE regards it as a single TRP transmission and performs the corresponding operation (for example, only receives one PDSCH with the highest priority).

[0273] In this embodiment, Methods 1 to 6 are not mutually exclusive, and one or more methods can be combined and used according to conditions. For example, Method 1 can be applied to SLIV and PDSCH mapping types, and Method 4 can be applied to the k0 value. Various other combinations are possible, but not all possibilities are listed so as not to obscure the key points of the explanation.

[0274] <Fourth Embodiment: UE Capability Signaling for NC-JT Reception and Its Resource Allocation Method>

[0275] In this embodiment, a time-domain and frequency-domain resource allocation method considering UE capability signaling related to UE's NC-JT will be described.

[0276] The UE can perform a UE capability report including at least one of the following methods to notify the eNB whether it can receive the NC-JT PDSCH.

[0277] ● Method 1: The UE can notify the eNB whether it can receive only a single PDSCH associated with one TCI state (or QCL information), or multiple PDSCHs associated with multiple TCI states (or QCL information) simultaneously.

[0278] ● Method 2 (UE Capability on NC-JT with Overlapping PDSCHs): In the case where the UE in Method 1 can receive multiple PDSCHs associated with multiple TCI states (or QCL information) simultaneously, and the frequency resources of the simultaneously received PDSCHs indicated by the FD-RA value (or the time resources or DMRS pattern indicated by the TD-RA value) are consistent with each other, the UE can notify the eNB whether it can support simultaneous reception.

[0279] ● Method 3 (UE Capability on NC-JT with Non-Overlapping PDSCHs): In the case where the UE in Method 1 can receive multiple PDSCHs associated with multiple TCI states (or QCL information) simultaneously, and the frequency resources of the simultaneously received PDSCHs indicated by the FD-RA value (or the time resources or DMRS pattern indicated by the TD-RA value) are not consistent with each other, the UE can notify the eNB whether it can support simultaneous reception.

[0280] ● Method 4 (UE Capability on NC-JT with Partially Overlapping PDSCHs): In the case where the UE in Method 1 can receive multiple PDSCHs associated with multiple TCI states (or QCL information) simultaneously, and the frequency resources of the simultaneously received PDSCHs indicated by the FD-RA value (or the time resources or DMRS pattern indicated by the TD-RA value) are partially consistent with each other, the UE can notify the eNB whether it can support simultaneous reception.

[0281] If the UE notifies the eNB of supporting NC-JT based on overlapping PDSCH according to Method 2 and notifies that it cannot receive NC-JT based on non-overlapping PDSCH or partially overlapping PDSCH according to Method 3 or 4, the eNB needs to ensure that the FD-RA (or TD-RA) fields in different PDCCH DCIs that allocate NC-JT PDSCH to the UE have the same value. When the UE is instructed to receive PDSCH allocated by different FD-RA (or TD-RA) fields, the UE may not receive the entire PDSCH or may only receive one PDSCH with the highest priority in the corresponding PDSCH.

[0282] If the UE notifies the eNB of supporting NC-JT based on non-overlapping PDSCH according to Method 3 and notifies that it cannot receive NC-JT based on overlapping PDSCH or partially overlapping PDSCH according to Method 2 or 4, the eNB needs to ensure that the FD-RA (or TD-RA) fields in different PDCCH DCIs that allocate NC-JT PDSCH to the UE have different values. If the UE is instructed to receive PDSCH sent from partially overlapping frequency (or time) resources, the UE may not receive the entire PDSCH or may only receive one PDSCH with the highest priority in the corresponding PDSCH.

[0283] Figure 16 A block diagram showing the structure of a UE according to an embodiment of the present disclosure is shown.

[0284] Referring to Figure 16 , the UE may include transceivers 16-00 and 16-10 and a processor 16-05 including a memory and a processor. According to the above communication method of the UE, the transceivers 16-00 and 16-10 and the processor 16-05 of the UE can operate. However, the components of the UE are not limited to the above examples. For example, the UE may include more components or fewer components than the above components. In addition, the transceivers 16-00 and 16-10 and the processor 16-05 may be implemented in the form of a single chip.

[0285] The transceivers 16-00 and 16-10 can send signals to the eNB and receive signals from the eNB. Here, the signals may include control information and data. For this purpose, the transceivers 16-00 and 16-10 may include an RF transmitter for up-converting and amplifying the frequency of the transmitted signal, and an RF receiver for low-noise amplifying the received signal and down-converting its frequency. However, this is only an embodiment of the transceiver 16-00 or 16-10, and the components of the transceivers 16-00 and 16-10 are not limited to the RF transmitter and the RF receiver.

[0286] In addition, transceivers 16-00 and 16-10 can receive signals through a wireless channel, output the received signals to processor 16-05, and transmit the signals output from processor 16-05 through the wireless channel.

[0287] Processor 16-05 can store programs and data required for the operation of the UE. In addition, processor 16-05 can store control information or data included in the signals obtained from the UE. Processor 16-05 can include a memory or a combination of storage media composed of storage media such as ROM, RAM, hard disk, CD-ROM, and DVD. Processor 16-05 can be electrically connected to receiver 16-00 and transmitter 16-10, and processor 16-05 can include at least one processor.

[0288] In addition, processor 16-05 can control a series of processes so that the UE can operate according to the above embodiments. According to some embodiments, processor 16-05 can control components of the UE to receive multiple PDSCHs simultaneously by receiving DCI composed of two layers.

[0289] Figure 17 A block diagram showing the structure of an eNB according to an embodiment of the present disclosure is shown.

[0290] Referring to Figure 17 , the eNB can include transceivers 17-00 and 17-10 and processor 17-05 including a memory and a processor. According to the above communication method of the eNB, transceivers 17-00 and 17-10 and processor 17-05 of the eNB can operate. However, the components of the eNB are not limited to the above examples. For example, the eNB can include more components or fewer components than the above components. In addition, transceivers 17-00 and 17-10 and processor 17-05 can be implemented in the form of a single chip.

[0291] Transceivers 17-00 and 17-10 can send signals to the UE and receive signals from the UE. Here, the signals can include control information and data. For this purpose, transceivers 17-00 and 17-10 can include an RF transmitter for up-converting and amplifying the frequency of the transmitted signal, and an RF receiver for low-noise amplifying the received signal and down-converting its frequency. However, this is only an embodiment of transceivers 17-00 or 17-10, and the components of transceivers 17-00 and 17-10 are not limited to the RF transmitter and the RF receiver.

[0292] In addition, transceivers 17-00 and 17-10 can receive signals through a wireless channel, output the signal to processor 17-05, and transmit the signal output from processor 17-05 through the wireless channel.

[0293] The processor 17-05 can store programs and data required for eNB operations. In addition, the processor 17-05 can store control information or data included in signals obtained from the eNB. The processor 17-05 can include a memory or a combination of storage media composed of storage media such as ROM, RAM, hard disk, CD-ROM, and DVD. The processor 17-05 can be electrically connected to the receiver 17-00 and the transmitter 17-10, and the processor 17-05 can include at least one processor.

[0294] The processor 17-05 can control a series of processes such that the eNB can operate according to the above-described embodiments of the present disclosure. According to some embodiments, the processor 17-05 can control the respective components of the eNB to configure and transmit DCI of two layers including allocation information for a plurality of PDSCHs.

[0295] Although the present disclosure has been described with various embodiments, those skilled in the art can suggest various changes and modifications. The present disclosure is intended to include such changes and modifications that fall within the scope of the appended claims.

Claims

1. A method for a user equipment (UE) in a communication system, the method comprising: Sending, to a base station, capability information of the UE related to a scheme for receiving a physical downlink shared channel (PDSCH); Receiving, from the base station, a physical downlink control channel (PDCCH), the PDCCH including a single downlink control information (DCI), the single DCI indicating two transmission configuration indication (TCI) states; And Receiving, based on the DCI, two PDSCHs, wherein the two PDSCHs include a first PDSCH and a second PDSCH having non-overlapping time-domain resource allocations or non-overlapping frequency-domain resource allocations; Wherein the two PDSCHs are associated with one or more demodulation reference signal (DMRS) ports, and the one or more DMRS ports are in a group, Wherein the two TCI states are associated with the first PDSCH and the second PDSCH having non-overlapping time-domain resource allocations or non-overlapping frequency-domain resource allocations.

2. The method according to claim 1, wherein The first PDSCH and the second PDSCH have non-overlapping frequency-domain resource allocations, and Wherein a specified number of first physical resource blocks (PRBs) corresponding to the first PDSCH correspond to a first TCI state, and the remaining PRBs corresponding to the second PDSCH correspond to a second TCI state.

3. The method according to claim 1, wherein, The one group is a code division multiplexing (CDM) group without data indicated by a field in the DCI.

4. A method for a base station in a communication system, the method comprising: Receiving, from a user equipment (UE), capability information of the UE related to a scheme for receiving a physical downlink shared channel (PDSCH); Sending, to the UE, a physical downlink control channel (PDCCH), the PDCCH including a single downlink control information (DCI), the single DCI indicating two transmission configuration indication (TCI) states; and Sending, based on the DCI, two PDSCHs to the UE, wherein the two PDSCHs include a first PDSCH and a second PDSCH having non-overlapping time-domain resource allocations or non-overlapping frequency-domain resource allocations; Wherein the two PDSCHs are associated with one or more demodulation reference signal (DMRS) ports, and the one or more DMRS ports are in a group, Wherein the two TCI states are associated with the first PDSCH and the second PDSCH having non-overlapping time-domain resource allocations or non-overlapping frequency-domain resource allocations.

5. The method according to claim 4, wherein, The first PDSCH and the second PDSCH have non-overlapping frequency-domain resource allocations, and Wherein a specified number of first physical resource blocks (PRBs) corresponding to the first PDSCH correspond to a first TCI state, and the remaining PRBs corresponding to the second PDSCH correspond to a second TCI state.

6. The method according to claim 4, wherein, The one group is a code division multiplexing (CDM) group without data indicated by a field in the DCI.

7. A user equipment (UE) in a communication system, the UE comprising: A transceiver; And A controller configured to: Send the capability information related to the scheme of the UE for receiving the Physical Downlink Shared Channel (PDSCH) to the base station via the transceiver; Receive a Physical Downlink Control Channel (PDCCH) from the base station via the transceiver, where the PDCCH includes a single Downlink Control Information (DCI), and the single DCI indicates two Transmission Configuration Indicator (TCI) states; And Based on the DCI, receive two PDSCHs, where the two PDSCHs include a first PDSCH and a second PDSCH with non-overlapping time-domain resource allocations or non-overlapping frequency-domain resource allocations; Wherein, the two PDSCHs are associated with one or more Demodulation Reference Signal (DMRS) ports, and the one or more DMRS ports are in a group, Wherein, the two TCI states are associated with the first PDSCH and the second PDSCH with non-overlapping time-domain resource allocations or non-overlapping frequency-domain resource allocations.

8. The UE according to claim 7, wherein The first PDSCH and the second PDSCH have non-overlapping frequency-domain resource allocations, and Wherein, a specified number of first Physical Resource Blocks (PRBs) corresponding to the first PDSCH correspond to the first TCI state, and the remaining PRBs corresponding to the second PDSCH correspond to the second TCI state.

9. The UE according to claim 7, wherein, The group is a Code Division Multiplexing (CDM) group without data indicated by a field in the DCI.

10. A base station in a communication system, the base station includes: A transceiver; A controller configured to: Receive the capability information related to the scheme of the User Equipment (UE) for receiving the Physical Downlink Shared Channel (PDSCH) from the UE via the transceiver; Send a Physical Downlink Control Channel (PDCCH) to the UE via the transceiver, where the PDCCH includes a single Downlink Control Information (DCI), and the single DCI indicates two Transmission Configuration Indicator (TCI) states; and Based on the DCI, send two PDSCHs to the UE via the transceiver, where the two PDSCHs include a first PDSCH and a second PDSCH with non-overlapping time-domain resource allocations or non-overlapping frequency-domain resource allocations; Wherein, the two PDSCHs are associated with one or more Demodulation Reference Signal (DMRS) ports, and the one or more DMRS ports are in a group, Wherein, the two TCI states are associated with the first PDSCH and the second PDSCH with non-overlapping time-domain resource allocations or non-overlapping frequency-domain resource allocations.

11. The base station according to claim 10, wherein, The first PDSCH and the second PDSCH have non-overlapping frequency-domain resource allocations, and Wherein, a specified number of first Physical Resource Blocks (PRBs) corresponding to the first PDSCH correspond to the first TCI state, and the remaining PRBs corresponding to the second PDSCH correspond to the second TCI state.

12. The base station according to claim 10, wherein, The group is a Code Division Multiplexing (CDM) group without data indicated by a field in the DCI.

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