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

Abstract

The present invention provides terminals and base stations for 5G or 6G wireless communication systems, as well as methods performed using these. [Solution] The method comprises the steps of: the terminal receiving time-domain resource allocation (TDRA) information from a base station; the terminal receiving downlink control information (DCI) from the base station, including a TDRA field and an antenna port field for scheduling a plurality of physical downlink shared channels (PDSCHs) 1301 to 1304; if a first method is used for the antenna port field, the terminal applying the value of the antenna port field to each of the plurality of PDSCHs; and if a second method is used for the antenna port field, the terminal applying the first bit field of the antenna port field to the first PDSCH and the second bit field of the antenna port field to the second PDSCH.

Description

Technical Field

[0001] The present invention relates to operations of a terminal and a base station in a wireless communication system, and more particularly, to a method for a terminal to interpret an antenna port field of a DCI (downlink control information) format and an apparatus for performing the same. Further, the present invention relates to a method for a terminal to interpret a phase tracking reference signal (PTRS) related field of a DCI format and an apparatus for performing the same.

Background Art

[0002] 5G mobile communication technology defines a wide frequency band to enable high transmission rates and new services, and is implemented not only in frequency bands below 6 GHz (‘Sub 6GHz’), such as 3.5 gigahertz (3.5 GHz), but also in extremely high frequency bands (‘Above 6GHz’) called mmWave, such as 28 GHz and 39 GHz. In the case of 6G mobile communication technology, called a system beyond 5G communication, in order to achieve a transmission speed 50 times faster and an ultra-low (Ultra Low) latency time at one-tenth level than 5G mobile communication technology, implementation in a terahertz (Terahertz) band (for example, like a 95 GHz to 3 THz band) is considered.

[0003] In the early stages of 5G mobile communication technology, the goal was to satisfy the service support and performance requirements for enhanced Mobile Broadband (eMBB), Ultra-Reliable Low-Latency Communications (URLLC), and massive Machine-Type Communications (mMTC). This included beamforming and Massive MIMO to mitigate path loss and increase propagation distance in the ultra-high frequency band, diverse pneumatic support (such as multi-subcarrier spacing manipulation) and dynamic manipulation of slot formats for efficient utilization of ultra-high frequency resources, initial connection techniques to support multiple beam transmission and broadband, definition and manipulation of Band-Width Parts (BWP), new channel coding methods such as Low-Density Parity Check (LDPC) codes for high-capacity data transmission and Polar Code for reliable transmission of control information, L2 pre-processing, and network slicing to provide dedicated networks specialized for specific services. Standardization has been progressing for techniques such as slicing.

[0004] Currently, discussions are underway to improve and enhance early 5G mobile communication technologies, taking into account the services that 5G mobile communication technology was intended to support. Physical layer standardization is progressing for technologies such as V2X (Vehicle-to-Everything), which helps autonomous vehicles make driving decisions based on their own location and status information to increase user convenience; NR-U (New Radio Unlicensed), which aims for system operation that complies with various regulatory requirements in non-licensed bands; NR terminal low power consumption technology (UE Power Saving); Non-Terrestrial Network (NTN), which is terminal-satellite direct communication to ensure coverage in areas where communication with terrestrial networks is impossible; and positioning.

[0005] Furthermore, standardization of wireless interface architectures / protocols is progressing for technologies such as IOT (Industrial Internet of Things) to support new services through collaboration and integration with other industries, IAB (Integrated Access and Backhaul) which provides nodes for network service area expansion by integrating support for wireless backhaul links and access links, Mobility Enhancement including Conditional Handover and DAPS (Dual Active Protocol Stack) handover, and 2-step RACH for NR to simplify random access procedures. Standardization in the system architecture / service field is also progressing for 5G baseline architectures (e.g., Service-based Architecture, Service-based Interface) to combine Network Functions Virtualization (NFV) and Software-Defined Networking (SDN) technologies, and Mobile Edge Computing (MEC) for receiving services based on terminal location.

[0006] As 5G mobile communication systems become commercialized, the explosively increasing number of connected devices will be linked to the communication network. Accordingly, improvements in the functionality and performance of 5G mobile communication systems, as well as the integrated operation of connected devices, are expected to be necessary. For this reason, new research is planned on improving 5G performance and reducing complexity using Extended Reality (XR), Artificial Intelligence (AI), and Machine Learning (ML) to efficiently support Augmented Reality (AR), Virtual Reality (VR), and Mixed Reality (MR), as well as AI service support, Metabus service support, and drone communications.

[0007] Furthermore, the development of such 5G mobile communication systems can serve as a foundation for the development of new technologies to ensure terahertz band coverage for 6G mobile communication technology, including novel waveforms, multi-antenna transmission technologies such as Full Dimensional MIMO (FD-MIMO), array antennas, and large-scale antennas, metamaterial-based lenses and antennas to improve terahertz band signal coverage, high-dimensional spatial multiplexing technologies using Orbital Angular Momentum (OAM), and Reconfigurable Intelligent Surface (RIS) technologies. In addition, it can provide a foundation for the development of AI-based communication technologies that utilize satellites and artificial intelligence (AI) from the design stage to optimize the system by internalizing end-to-end AI support functions, and next-generation distributed computing technologies that realize services of a complexity exceeding the limits of terminal computing power by utilizing ultra-high-performance communication and computing resources. [Overview of the project] [Problems that the invention aims to solve]

[0008] The present invention has been made in view of the above-mentioned prior art, and the object of the present invention is to provide an apparatus and method for effectively providing services in a mobile communication system. [Means for solving the problem]

[0009] The present invention was made to solve the above-mentioned problems and drawbacks and to provide at least the advantages described below.

[0010] A method performed by a terminal in a wireless communication system according to one aspect of the present invention, made to achieve the above objective, is characterized by comprising the steps of: receiving time domain resource assignment (TDRA) information from a base station; receiving downlink control information (DCI) from the base station, including a TDRA field and an antenna port field for scheduling a plurality of physical downlink shared channels (PDSCH); if a first method is used for the antenna port field, applying the value of the antenna port field to each of the plurality of physical downlink shared channels; and if a second method is used for the antenna port field, applying the first bit field of the antenna port field to the first physical downlink shared channel and the second bit field of the antenna port field to the second physical downlink shared channel.

[0011] A method performed by a base station in a wireless communication system according to one embodiment comprises the steps of transmitting a higher-level signal including time domain resource assignment (TDRA) information to a terminal, and transmitting downlink control information including an antenna port field to the terminal, wherein if the DCI includes multiple scheduling information of different mapping types, an antenna port table of a first mapping type and an antenna port table of a second mapping type are identified based on the antenna port field.

[0012] A terminal in a wireless communication system according to one embodiment comprises a transmitting / receiving unit and a control unit, wherein the control unit receives a higher-level signal including time domain resource assignment (TDRA) information from a base station, receives downlink control information including an antenna port field from the base station, and is configured to identify an antenna port table of a first mapping type and an antenna port table of a second mapping type based on the antenna port field when the DCI includes multiple scheduling information of different mapping types.

[0013] A base station in a wireless communication system according to one embodiment comprises a transmitting / receiving unit and a control unit, wherein the control unit is configured to transmit a higher-level signal including time domain resource assignment (TDRA) information to a terminal and to transmit downlink control information (DCI) including an antenna port field to the terminal, and when the DCI includes multiple scheduling information of different mapping types, an antenna port table of a first mapping type and an antenna port table of a second mapping type are identified based on the antenna port field. [Effects of the Invention]

[0014] According to the present invention, it is possible to provide a method and apparatus that can effectively provide services in a mobile communication system, in which a terminal interprets an antenna port field in DCI format and a terminal interprets a PTRS-related field in DCI format. [Brief explanation of the drawing]

[0015] [Figure 1] This figure shows the basic structure of the time-frequency domain in a wireless communication system according to one embodiment. [Figure 2] This figure shows the frame, subframe, and slot structure in a wireless communication system according to one embodiment. [Figure 3] This figure shows an example of bandwidth partial setting in a wireless communication system according to one embodiment. [Figure 4] This figure shows the control region setting for the downlink control channel in a wireless communication system according to one embodiment. [Figure 5] This figure shows the structure of a downlink control channel in a wireless communication system according to one embodiment. [Figure 6]FIG. is for explaining a method for a base station and a terminal to transmit and receive data in consideration of a downlink data channel and rate matching resources in a wireless communication system according to an embodiment. [Figure 7] FIG. shows the frequency axis resource allocation of a PDSCH (physical downlink shared channel) in a wireless communication system according to an embodiment. [Figure 8] FIG. shows the time axis resource allocation of a PDSCH in a wireless communication system according to an embodiment. [Figure 9] FIG. shows the time axis resource allocation according to the subcarrier spacing of a data channel and a control channel in a wireless communication system according to an embodiment. [Figure 10] FIG. shows the radio protocol structure of a base station and a terminal in a single cell, carrier aggregation, and dual connectivity situation in a wireless communication system according to an embodiment. [Figure 11] FIG. shows a PDSCH scheduling method according to an embodiment. [Figure 12] FIG. shows the DCI of Single-PDSCH scheduling and Multi-PDSCH scheduling according to an embodiment. [Figure 13] FIG. is for explaining the HARQ (hybrid automatic repeat request)-ACK (acknowledgement) transmission of one or more PDSCHs scheduled by DCI when DCI instructs Multi-PDSCH scheduling according to an embodiment. [Figure 14] FIG. shows the structure of a terminal in a wireless communication system according to an embodiment. [Figure 15] FIG. shows the structure of a base station in a wireless communication system according to an embodiment.

MODE FOR CARRYING OUT THE INVENTION

[0016] Hereinafter, specific examples of embodiments for implementing the present invention will be described in detail while referring to the drawings. However, it should be understood that various embodiments of the present invention are not limited to specific embodiments, and it is possible in various ways to modify, provide equivalents, and / or replace the embodiments described herein. In the description of the drawings, similar components are given similar reference numerals.

[0017] Various embodiments of the present invention provide a method for a terminal configured with multi - PDSCH (physical downlink shared channel) scheduling and multi - PUSCH (physical uplink shared channel) scheduling in a wireless communication system to interpret an antenna port field.

[0018] With multi - PDSCH scheduling and multi - PUSCH scheduling configured, the terminal receives multiple scheduling information in one TDRA (Time Domain Resource Assignment) row, and each of the multiple scheduling information has an SLIV (Starting and Length Indication Value) and a mapping type. Therefore, the terminal according to various embodiments of the present invention receives an indication of a TDRA row including scheduling information with different mapping types through one DCI.

[0019] Different DMRS setting information is set for different mapping types. When the DMRS setting information is different, the antenna port table for DMRS port indication is different. The DCI format for scheduling PDSCH or PUSCH according to various embodiments of the present invention includes an antenna port field for indicating one row of the antenna port table.

[0020] When a single DCI points to a TDRA row containing scheduling information with different mapping types, that single DCI must point to each row in multiple tables. In various embodiments of the present invention, each row in multiple antenna port tables is pointed to by providing an antenna port field design and interpretation method included in the DCI format.

[0021] Different mapping types are configured with different DMRS configuration information. When the DMRS configuration information differs, the antenna port table used to direct the DMRS information is different. Therefore, different DMRS port(s) are assigned to different mapping types.

[0022] When a TDRA row containing scheduling information with different mapping types is indicated through a single DCI, the PTRS-DMRS association field indicates one of each of the two mapping types of DMRS port(s). This specification provides various methods for this purpose.

[0023] In describing embodiments of the present invention, technical details that are well known in the art to which the present invention belongs and are not directly related to the present invention will be omitted. This is to clarify and more clearly communicate the gist of the present invention by omitting unnecessary explanations.

[0024] For similar reasons, some components are exaggerated, omitted, or only schematically represented in the drawings. Furthermore, the sizes of each component do not fully reflect their actual dimensions. The same or corresponding components are given the same reference number in each drawing.

[0025] The advantages and features of the present invention, as well as methods for achieving them, will become apparent by referring to the embodiments described below in detail in conjunction with the drawings. However, the present invention is not limited to the embodiments described below and can be implemented in a variety of different forms. The following embodiments are provided solely to fully disclose the present invention and to inform those skilled in the art of the scope of the invention as defined by the claims. The same or similar reference numerals throughout the specification indicate the same or similar elements. In describing the present invention, detailed descriptions of known functions and configurations included herein are omitted if it is determined that such descriptions may unnecessarily obscure the subject matter of the invention. The terms described below are defined in consideration of the functions of the present invention and may differ depending on the user, user intent, convention, etc. Therefore, the definitions of terms should be based on the content of the entire specification.

[0026] At this point, it can be understood that the combination of each block in the processing flowchart and the diagrams in the flowchart is performed by computer program instructions. These computer program instructions are installed on the processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, and the instructions, executed via the processor of the computer or other programmable data processing device, generate means for performing the functions described in the flowchart blocks. These computer program instructions can also be stored in computer-available or computer-readable memory directed to the computer or other programmable data processing device to embody the functions in a particular manner, and the instructions stored in that computer-available or computer-readable memory can produce manufactured items that contain instruction means for performing the functions described in the flowchart blocks. Since computer program instructions can also be installed on a computer or other programmable data processing device, a series of operational steps are performed on the computer or other programmable data processing device, and the instructions that generate a process executed on the computer and operate the computer or other programmable data processing device provide steps for performing the functions described in the flowchart blocks.

[0027] Furthermore, each block represents a module, segment, or portion of code containing one or more executable instructions for performing a specified logical function. It should also be noted that in some alternative execution examples, the functions mentioned in a block may occur out of order. For example, two adjacent blocks may actually be performed substantially simultaneously, or the blocks may sometimes be performed in reverse order by the functions in question.

[0028] In this embodiment, the term “~part” refers to software or hardware components such as FPGAs (Field Programmable Gate Arrays) or ASICs (Application Specific Integrated Circuits), and “~part” performs such a role. However, “~part” is not limited to software or hardware. “~part” may be configured to reside in an addressable storage medium, or to regenerate one or more processors. Thus, as an example, “~part” includes components such as software components, object-oriented software components, class components, and task components, as well as processes, functions, attributes, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functions provided by components and “~part” may be combined into a smaller number of components and “~part” or further separated into additional components and “~part”. Moreover, components and “~part” may be embodied to regenerate one or more CPUs within a device or security multimedia card. Furthermore, in the embodiment, the “~ section” includes one or more processors.

[0029] Wireless communication systems have moved beyond providing early voice-centric services and have evolved into broadband wireless communication systems that provide high-speed, high-quality packet data services, such as 3GPP®'s HSPA (High Speed ​​Packet Access), LTE (Long Term Evolution or E-UTRA (Evolved Universal Terrestrial Radio Access)), LTE-Advanced (LTE-A), LTE-Pro, 3GPP®'s HRPD (High Rate Packet Data), UMB (Ultra Mobile Broadband), and IEEE's 802.16e.

[0030] In the LTE system, a typical example of a broadband wireless communication system, the OFDM (Orthogonal Frequency Division Multiplexing) method is used for the downlink (DL), and the SC-FDMA (Single Carrier Frequency Division Multiple Access) method is used for the uplink (UL). The uplink refers to the radio link on which a terminal (UE (User Equipment) or MS (Mobile Station)) transmits data or control signals to a base station (eNode B, or base station (BS)), while the downlink refers to the radio link on which a base station transmits data or control signals to a terminal. In the above multiplexing methods, the data or control information for each user is usually divided by allocating and operating the time-frequency resources for transmitting data or control information for each user so that they do not overlap, i.e., orthogonality is established.

[0031] As a communication system following LTE, i.e., a 5G communication system, it is necessary to freely reflect the diverse demands of users and service providers, and therefore it is necessary to support services that meet these diverse demands. Services to be considered for 5G communication systems include eMBB (enhanced Mobile Broadband), mMTC (massive Machine Type Communication), and URLLC (Ultra Reliability Low Latency Communication).

[0032] eMBB aims to provide higher data transmission speeds than those supported by existing LTE, LTE-A, or LTE-Pro. For example, in a 5G communication system, eMBB must provide a peak data rate of 20 Gbps downlink and a peak data rate of 10 Gbps uplink from the perspective of a single base station. In addition, a 5G communication system must provide increased user-perceived data rate while simultaneously providing the peak data rate. To satisfy these requirements, improvements in various transmission and reception technologies are required, including improved Multi-Input Multi-Output (MIMO) transmission technology. Furthermore, while LTE uses a maximum transmission bandwidth of 20 MHz in the 2 GHz band to transmit signals, a 5G communication system will satisfy the data transmission speed required by using a wider frequency bandwidth than 20 MHz in the 3-6 GHz or above frequency band.

[0033] Simultaneously, mMTC is being considered to support application services such as the Internet of Things (IoT) in 5G communication systems. mMTC requires support for large-scale terminal connectivity within cells, improved terminal coverage, extended battery life, and reduced terminal costs to efficiently deliver the IoT. Because the IoT involves various sensors and diverse devices providing communication capabilities, it must support a large number of terminals within a cell (e.g., 1,000,000 terminals / km2). Furthermore, terminals supporting mMTC are likely to be located in shaded areas not covered by the cell, such as the basements of buildings, due to the nature of the service, thus requiring wider coverage than other services offered by 5G communication systems. mMTC-supporting terminals must be inexpensive to build and require a very long battery life (10 to 16 years) because frequent battery replacement is difficult.

[0034] Finally, URLLC is a cellular-based wireless communication service used for specific (mission-critical) purposes. For example, consider services used for remote control of robots or machinery, industrial automation, unmanned aerial vehicles, remote health care, and emergency alerts. Therefore, the communication provided by URLLC must also offer very low latency and very high reliability. For example, services supporting URLLC must satisfy an air interface latency of less than 0.5 milliseconds and simultaneously have a packet error rate of 10⁻⁵ or less. Consequently, 5G systems supporting URLLC must provide a shorter transmit time interval (TTI) than other services and simultaneously require design considerations such as allocating a wide resource in the frequency band to ensure the reliability of the communication link.

[0035] The three 5G services, eMBB, URLLC, and mMTC, are multiplexed and transmitted within a single system. In this case, different transmission and reception techniques and parameters are used between the services to meet the different requirements of each service. Of course, 5G is not limited to the three services mentioned above.

[0036] This explains the NR time-frequency resource.

[0037] Figure 1 is a diagram showing the basic structure of the time-frequency domain in a wireless communication system according to one embodiment, and is a diagram showing the basic structure of the time-frequency domain, which is the wireless resource domain to which data or control channels are transmitted in a 5G system.

[0038] In Figure 1, the horizontal axis represents the time domain, and the vertical axis represents the frequency domain. In the time and frequency domains, the basic unit of a resource is defined as a Resource Element (RE) 101, represented by 1 OFDM (Orthogonal Frequency Division Multiplexing) symbol 102 on the time axis, and 1 Subcarrier 103 on the frequency axis. Consecutive REs (Resource Elements) of TIFF2026102837000002.tif9128 (for example, 12) constitute one Resource Block (RB) 104. One subframe 110 consists of multiple OFDM symbols. For example, the length of subframe 110 is 1 ms.

[0039] Figure 2 shows the frame, subframe, and slot structure in a wireless communication system according to one embodiment.

[0040] Figure 2 shows an example of a frame (Frame) 200, subframe (Subframe) 201, and slot (Slot) 202 structure. One frame (Frame) 200 is defined as 10ms. One subframe (Subframe) 201 is defined as 1ms, and therefore one frame (Frame) 200 consists of a total of 10 subframes (Subframes). One slot (202, 203) is defined as 14 OFDM symbols (i.e., the number of symbols per slot). TIFF2026102837000003.tif111281 Subframe 201 consists of one or more slots (202, 203), and the number of slots (202, 203) per subframe 201 varies depending on the setting value μ (204, 205) for the subcarrier interval. Figure 2 shows an example where the subcarrier interval setting value is μ=0 (204) and μ=1 (205). When μ=0 (204), one subframe 201 consists of one slot 202, and when μ=1 (205), one subframe 201 consists of two slots 203. That is, the number of slots per subframe varies depending on the setting value μ for the subcarrier interval. TIFF2026102837000004.tif11128 has been changed, resulting in a change to the number of slots per frame. TIFF2026102837000005.tif11128 will change. This depends on the subcarrier spacing setting μ. Defined in Table 1 below, TIFF2026102837000006.tif10128.

[0041] [Table 1]

[0042] Next, we will specifically explain the settings for the bandwidth portion (BWP) in a 5G communication system, referring to the diagram.

[0043] Figure 3 shows an example of bandwidth partial setting in a wireless communication system according to one embodiment.

[0044] Figure 3 shows an example where the terminal bandwidth (UE bandwidth) 300 is configured into two bandwidth portions, namely bandwidth portion #1 (BWP#1) 301 and bandwidth portion #2 (BWP#2) 302. The base station configures one or more bandwidth portions for the terminal and sets the information shown in Table 2 below for each bandwidth portion.

[0045] [Table 2]

[0046] Of course, this is not limited to the examples, and various parameters related to bandwidth portions are set on the terminal in addition to the configuration information. This information is transmitted from the base station to the terminal through higher-level signaling, such as RRC (Radio Resource Control) signaling. At least one of the one or more configured bandwidth portions is activated. Whether or not to activate a configured bandwidth portion is transmitted from the base station to the terminal either quasi-statically through RRC signaling or dynamically through DCI (Downlink Control Information).

[0047] In some embodiments, before an RRC (Radio Resource Control) connection is established, the terminal has an initial bandwidth portion (Initial BWP) set by the base station via the MIB (Master Information Block) for the initial connection. More specifically, at the initial connection stage, the terminal receives configuration information for the control resource set (CORESET) and search space via the MIB, which transmits a PDCCH (Plant, Control, and Control Channel) to receive the system information necessary for the initial connection (corresponding to Remaining System Information: RMSI or System Information Block 1: SIB1). The control resource set and search space set in the MIB are considered to have their respective identifiers (Identity: ID) 0. The base station notifies the terminal of configuration information such as frequency allocation information, time allocation information, and numerology for control resource set #0 via the MIB. The base station also notifies the terminal of configuration information for the monitoring period and occasion for control resource set #0, i.e., configuration information for search space #0, via the MIB. The terminal considers the frequency range set in control resource set #0 obtained from the MIB as the initial bandwidth portion for the initial connection. At this time, the identifier (ID) of the initial bandwidth portion is considered to be 0.

[0048] The settings for the bandwidth portion supported by 5G are used for a variety of purposes.

[0049] According to some embodiments, when the bandwidth supported by the terminal is smaller than the system bandwidth, this is supported through bandwidth portion setting. For example, the base station sets the frequency position of the bandwidth portion (setting information 2) on the terminal, so that the terminal sends and receives data at a specific frequency position within the system bandwidth.

[0050] Furthermore, according to some embodiments, a base station sets multiple bandwidth portions on a terminal for the purpose of supporting different pneumatics. For example, to support both data transmission and reception using 15kHz and 30kHz subcarrier intervals on a terminal, two bandwidth portions are set with 15kHz and 30kHz subcarrier intervals, respectively. The different bandwidth portions are subjected to frequency division multiplexing, and when attempting to transmit or receive data using a specific subcarrier interval, the bandwidth portion set for that subcarrier interval is activated.

[0051] Furthermore, according to some embodiments, in order to reduce terminal power consumption, the base station sets bandwidth portions with different bandwidth sizes for the terminal. For example, if the terminal supports a very large bandwidth, such as 100MHz, and constantly sends and receives data in that bandwidth, very large power consumption occurs. In particular, monitoring unnecessary downlink control channels with a large bandwidth of 100MHz when there is no traffic is very inefficient from a power consumption standpoint. In order to reduce terminal power consumption, the base station sets a bandwidth portion with a relatively small bandwidth, such as 20MHz, for the terminal. When there is no traffic, the terminal performs monitoring operations in the 20MHz bandwidth portion, and when data is generated, it sends and receives data in the 100MHz bandwidth portion according to the base station's instructions.

[0052] In the method of configuring the bandwidth portion, terminals prior to RRC connection (Connected) receive configuration information for the Initial Bandwidth Part via the MIB (Master Information Block) during the initial connection phase. More specifically, the terminal has a Control Resource Set (CORESET) configured for the downlink control channel from which DCI (Downlink Control Information) scheduling SIBs (System Information Blocks) is transmitted, based on the PBCH (Physical Broadcast Channel) MIB. The bandwidth of the control portion configured in the MIB is considered the initial bandwidth portion, and the terminal receives the PDSCH (Physical Downlink Shared Channel) from which SIBs are transmitted through this configured initial bandwidth portion. In addition to receiving SIBs, the initial bandwidth portion is also used for other system information (OSI), paging, and random access.

[0053] This section explains the changes to the bandwidth portion (BWP).

[0054] If a terminal has one or more bandwidth parts configured, the base station uses the Bandwidth Part Indicator field in the DCI to instruct the terminal to change (or switch, transition) to a bandwidth part. For example, if the terminal's currently activated bandwidth part is Bandwidth Part #1 (301) in Figure 3, the base station instructs the terminal to change to Bandwidth Part #2 (302) using the Bandwidth Part Indicator in the DCI, and the terminal changes its bandwidth part to Bandwidth Part #2 (302) as indicated by the received Bandwidth Part Indicator in the DCI.

[0055] As described above, since partial bandwidth changes in the DCI infrastructure are instructed by the DCI scheduling the PDSCH or PUSCH, when a terminal receives a partial bandwidth change request, it must be able to receive or transmit the PDSCH or PUSCH scheduled by that DCI in the changed bandwidth portion without difficulty. For this reason, the standard specifies requirements for the time by which partial bandwidth changes are required (TBWP), which are defined, for example, as shown in Table 3.

[0056] [Table 3]

[0057] The requirements for bandwidth portion delay time support either Type 1 or Type 2, depending on the terminal's capability. The terminal reports the supported bandwidth portion delay time types to the base station.

[0058] Due to the above-mentioned requirements for bandwidth portion change delay time, when a terminal receives a DCI containing a bandwidth portion change indicator in slot n, the terminal completes the change to the new bandwidth portion indicated by the bandwidth portion change indicator at a time no later than slot n + TBWP and performs transmission and reception on the data channel scheduled by the DCI in the changed new bandwidth portion. When the base station attempts to schedule a data channel in the new bandwidth portion, it considers the terminal's bandwidth portion change delay time (TBWP) when determining the time domain resource allocation for the data channel. That is, when the base station schedules a data channel in the new bandwidth portion, it schedules the data channel after the bandwidth portion change delay time in a manner that determines the time domain resource allocation for the data channel. As a result, the terminal does not expect the DCI indicating a bandwidth portion change to indicate a slot offset (K0 or K2) value smaller than the bandwidth portion change delay time (TBWP).

[0059] When a terminal receives a DCI (e.g., DCI format 1_1 or 0_1) that indicates a partial bandwidth change, the terminal refrains from transmitting or receiving for the time interval corresponding to the third symbol of the slot that received the PDCCH containing the DCI, up to the start of the slot indicated by the time domain resource allocation indicator field and the indicated slot offset (K0 or K2) value within the DCI. For example, if a terminal receives a DCI indicating a partial bandwidth change in slot n, and the indicated slot offset value in the DCI is K, the terminal refrains from transmitting or receiving from the third symbol of slot n up to the symbol before slot n+K (i.e., the last symbol of slot n+K-1).

[0060] Let's explain the SS / PBCH block.

[0061] Next, we will explain the SS (Synchronization Signal) / PBCH block in 5G. The SS / PBCH block refers to a physical layer channel block composed of PSS (Primary SS), SSS (Secondary SS), and PBCH. Specifically, it is as follows:

[0062] -PSS is a signal that serves as the reference signal for downlink time / frequency synchronization and provides some information about the cell ID.

[0063] -SSS is a signal that serves as the downlink time / frequency synchronization reference and provides the remaining cell ID information that PSS does not provide. Additionally, it functions as a reference signal for PBCH demodulation.

[0064] - The PBCH is a channel that provides essential system information necessary for the transmission and reception of data and control channels at a terminal. This essential system information includes search space-related control information indicating the wireless resource mapping information of the control channel, and scheduling control information for a separate data channel that transmits system information.

[0065] -SS / PBCH Block: An SS / PBCH block consists of a combination of PSS, SSS, and PBCH. One or more SS / PBCH blocks are transmitted within a 5ms time frame, and each transmitted SS / PBCH block is distinguished by an index.

[0066] The terminal detects the PSS and SSS during the initial connection phase and decodes the PBCH. The terminal obtains the MIB from the PBCH and sets the Control Resource Set (CORESET) #0 (corresponding to the control area with a control area index of 0). The terminal monitors control area #0, assuming that the DMRS (Demodulation Reference signal) transmitted from the selected SS / PBCH block and control area #0 is QCL (Quasi Co Location). The terminal receives system information from the downlink control information transmitted from control area #0. From the received system information, the terminal obtains the RACH (Random Access Channel) related configuration information necessary for the initial connection. The terminal sends a PRACH (Physical RACH) to the base station, taking into account the selected SS / PBCH index, and the base station, upon receiving the PRACH, obtains information for the SS / PBCH block index selected by the terminal. The base station knows which of the SS / PBCH blocks the terminal has selected and which control area #0 it is monitoring.

[0067] Next, we will provide a specific explanation of Downlink Control Information (DCI) in 5G systems.

[0068] In a 5G system, scheduling information for uplink data (or Physical Uplink Shared Channel: PUSCH) or downlink data (or Physical Downlink Shared Channel: PDSCH) is transmitted from the base station to the terminal via DCI. The terminal monitors the DCI format for fallback and non-fallback for PUSCH or PDSCH. The fallback DCI format consists of fields that are defined and fixed between the base station and the terminal, while the non-fallback DCI format includes configurable fields.

[0069] DCI messages are transmitted via the Physical Downlink Control Channel (PDCCH) through channel coding and modulation processes. A Cyclic Redundancy Check (CRC) is attached to the DCI message payload, and the CRC is scrambled with a Radio Network Temporary Identifier (RNTI) corresponding to the terminal's identity. Different RNTIs are used depending on the purpose of the DCI message, such as terminal-specific (UE-specific) data transmission, power control commands, or random access responses. That is, the RNTI is not explicitly transmitted but is included in the CRC calculation process. When a terminal receives a DCI message transmitted over the PDCCH, it checks the CRC using its assigned RNTI, and if the CRC check is correct, the terminal knows that the message has been transmitted to it.

[0070] For example, DCIs that schedule PDSCHs for System Information (SI) are scrambled with SI-RNTI. DCIs that schedule PDSCHs for RAR (Random Access Response) messages are scrambled with RA-RNTI. DCIs that schedule PDSCHs for Paging messages are scrambled with P-RNTI. DCIs that notify SFI (Slot Format Indicator) are scrambled with SFI-RNTI. DCIs that notify TPC (Transmit Power Control) are scrambled with TPC-RNTI. DCIs that schedule terminal-specific PDSCHs or PUSCHs are scrambled with C-RNTI (Cell RNTI).

[0071] DCI format 0_0 is used in fallback DCI for scheduling PUSCH, in which case the CRC is scrambled by C-RNTI. DCI format 0_0 with the CRC scrambled by C-RNTI includes, for example, the information in Table 4.

[0072] [Table 4]

[0073] DCI format 0_1 ​​is used in non-fallback DCI for scheduling pushes, in which case the CRC is scrambled by C-RNTI. DCI format 0_1 ​​with the CRC scrambled by C-RNTI includes, for example, the information in Table 5.

[0074] [Table 5] TIFF2026102837000012.tif134169

[0075] DCI format 1_0 is used in fallback DCI for scheduling PDSCH, in which case the CRC is scrambled by C-RNTI. DCI format 1_0 with the CRC scrambled by C-RNTI includes, for example, the information in Table 6.

[0076] [Table 6]

[0077] DCI format 1_1 is used in non-fallback DCI for scheduling PDSCH, in which case the CRC is scrambled by C-RNTI. DCI format 1_1 with the CRC scrambled by C-RNTI includes, for example, the information in Table 7.

[0078] [Table 7]

[0079] The following section provides a more detailed explanation of the downlink control channel in a 5G communication system, with reference to the diagrams.

[0080] Figure 4 is a diagram showing the control area setting of a downlink control channel in a wireless communication system according to one embodiment, and is a diagram showing an example of the control area (Control Resource Set: CORESET) to which the downlink control channel is transmitted in a 5G wireless communication system.

[0081] Figure 4 shows an example in which the terminal bandwidth portion (UE bandwidth part) 410 is set on the frequency axis and two control areas (control area #1 (401) and control area #2 (402)) are set within one slot 420 on the time axis. The control areas (401, 402) are set on specific frequency resources 403 within the overall terminal bandwidth portion 410 on the frequency axis. The control areas are set on the time axis with one or more OFDM symbols, and this is defined by the control resource set duration (Control Resource Set Duration) 404. Referring to the example shown in Figure 4, control area #1 (401) is set with a control area duration of 2 symbols, and control area #2 (402) is set with a control area duration of 1 symbol.

[0082] The control area in 5G described above is configured on the terminal by the base station through higher-level signaling (e.g., System Information, MIB (Master Information Block), RRC (Radio Resource Control) signaling). Configuring a control area on the terminal means providing information such as the control area identifier (Identity), the frequency position of the control area, and the length of the control area symbol. This includes, for example, the information in Table 8.

[0083] [Table 8]

[0084] In Table 8, the tci-StatesPDCCH (simply called TCI (Transmission Configuration Indication) state) configuration information includes information on one or more SS (Synchronization Signal) / PBCH (Physical Broadcast Channel) block indices or CSI-RS (Channel State Information Reference Signal) indices that are transmitted in the corresponding control domain and are related to DMRS and QCL (Quasi Co Located).

[0085] Figure 5 shows the structure of a downlink control channel in a wireless communication system according to one embodiment, and illustrates an example of the basic units of time and frequency resources that constitute a downlink control channel used in 5G.

[0086] According to Figure 5, the basic unit of time and frequency resources that constitute a control channel is called a REG (Resource Element Group) 503. A REG 503 is defined by 1 OFDM symbol 501 on the time axis and 1 PRB (Physical Resource Block) 502 on the frequency axis, i.e., 12 subcarriers. Base stations connect REG 503s to form a downlink control channel allocation unit.

[0087] As shown in Figure 5, if the basic unit to which a downlink control channel is assigned in 5G is a CCE (Control Channel Element) 504, then 1 CCE 504 is composed of multiple REG 503s. Taking the REG 503 shown in Figure 5 as an example, a REG 503 is composed of 12 REs, and if 1 CCE 504 is composed of 6 REG 503s, then 1 CCE 504 is composed of 72 REs. When a downlink control area is established, that area is composed of multiple CCE 504s, and a specific downlink control channel is mapped and transmitted by one or more CCE 504s according to the Aggregation Level (AL) within the control area. The CCE 504s within the control area are divided into numbers, and at this time, the numbers of the CCE 504s are assigned according to a logical mapping scheme.

[0088] The basic unit of a downlink control channel, namely REG503, shown in Figure 5, includes both an RE to which the DCI is mapped and an area to which the DMRS505, a reference signal for decoding it, is mapped. As shown in Figure 5, three DMRS505s are transmitted within one REG503. The number of CCEs required to transmit a PDCCH is 1, 2, 4, 8, or 16, depending on the Aggregation Level (AL), and different numbers of CCEs are used to implement link adaptation of the downlink control channel. For example, when AL=L, one downlink control channel is transmitted through L CCEs. The terminal must detect the signal without knowing any information about the downlink control channel, but a search space is defined that shows a set of CCEs for blind decoding. A search space is a set of downlink control channel candidates (CCEs) that a terminal must attempt to decode at a given aggregation level. Since there are various aggregation levels that bundle 1, 2, 4, 8, or 16 CCEs into one bundle, a terminal has multiple search spaces. A search space set is defined as the set of search spaces for all configured aggregation levels.

[0089] Search spaces are classified into common search spaces and UE-specific search spaces. A certain group of terminals, or all terminals, search the common search space of PDCCH to receive cell-common control information such as dynamic scheduling and paging messages for system information. For example, PDSCH scheduling assignment information for SIB transmission, including cell operator information, is received by searching the common search space of PDCCH. In the case of the common search space, a certain group of terminals, or all terminals, must receive PDCCH, so it is defined as a set of pre-promised CCEs. Scheduling assignment information for UE-specific PDSCH or PUSCH is received by searching the UE-specific search space of PDCCH. The UE-specific search space is defined UE-specifically as a function of terminal identity and various system parameters.

[0090] In 5G, parameters for the search space for PDCCHs are set from the base station to the terminal using higher-level signaling (e.g., SIB, MIB, RRC signaling). For example, the base station sets on the terminal the number of PDCCH candidate groups at each aggregation level L, the monitoring period for the search space, the monitoring occasion for symbols within slots in the search space, the search space type (common search space or terminal-specific search space), the combination of DCI format and RNTI to be monitored in that search space, and the control area index to be monitored in the search space. For example, this includes the information in Table 9.

[0091] [Table 9] TIFF2026102837000017.tif81160

[0092] Depending on the configuration information, the base station configures one or more search space sets on the terminal. In one embodiment, the base station configures search space set 1 and search space set 2 on the terminal, configuring search space set 1 to monitor DCI format A scrambled by X-RNTI in a common search space, and configuring search space set 2 to monitor DCI format B scrambled by Y-RNTI in a terminal-specific search space.

[0093] According to the configuration information, there are one or more sets of search spaces in the common search space or the terminal-specific search space. For example, search space set #1 and search space set #2 are set as the common search space, and search space set #3 and search space set #4 are set as the terminal-specific search space.

[0094] The following DCI format and RNTI combinations are monitored in the common search space, but are not limited to the examples below.

[0095] DCI format 0_0 / 1_0 with CRC scrambled by C-RNTI,CS-RNTI,SP-CSI-RNTI,RA-RNTI,TC-RNTI,P-RNTI,SI-RNTI

[0096] DCI format 2_0 with CRC scrambled by SFI-RNTI

[0097] DCI format 2_1 with CRC scrambled by INT-RNTI

[0098] DCI format 2_2 with CRC scrambled by TPC-PUSCH-RNTI,TPC-PUCCH-RNTI

[0099] DCI format 2_3 with CRC scrambled by TPC-SRS-RNTI

[0100] In the terminal-specific search space, the following combinations of DCI formats and RNTI are monitored, but are not limited to the examples below.

[0101] DCI format 0_0 / 1_0 with CRC scrambled by C-RNTI,CS-RNTI,TC-RNTI

[0102] DCI format 1_0 / 1_1 with CRC scrambled by C-RNTI,CS-RNTI,TC-RNTI

[0103] The explicitly stated RNTI follows the definition and usage described below.

[0104] C-RNTI (Cell RNTI): Terminal-specific PDSCH scheduling application

[0105] TC-RNTI (Temporary Cell RNTI): Terminal-specific PDSCH scheduling application

[0106] CS-RNTI (Configured Scheduling RNTI): A quasi-statically configured terminal for specific PDSCH scheduling purposes.

[0107] RA-RNTI (Random Access RNTI): For PDSCH scheduling during the random access phase.

[0108] P-RNTI (Paging RNTI): Used for PDSCH scheduling where paging is sent.

[0109] SI-RNTI (System Information RNTI): Used for PDSCH scheduling where system information is transmitted.

[0110] INT-RNTI (Interruption RNTI): Used to notify whether or not to puncture PDSCH.

[0111] TPC-PUSCH-RNTI (Transmit Power Control for PUSCH RNTI): Used to issue power control commands to PUSCH.

[0112] TPC-PUCCH-RNTI (Transmit Power Control for PUCCH RNTI): Used to issue power control commands to PUCCH.

[0113] TPC-SRS-RNTI (Transmit Power Control for SRS RNTI): Used for issuing power control commands to SRS.

[0114] The explicitly defined DCI format described above follows the definitions shown in the example in Table 10.

[0115] [Table 10]

[0116] In 5G, a search space with a control region p, a search space set s, and an aggregation level L can be expressed as shown in Equation 1 below.

[0117]

number

[0118] The value of TIFF2026102837000020.tif11137 corresponds to 0 in the case of a common search space. The TIFF2026102837000021.tif10128 value corresponds to a value that changes depending on the terminal ID (C-RNTI or the ID set on the terminal by the base station) and the time index in the case of a terminal-specific search space.

[0119] In 5G, multiple search space sets are set to different parameters (for example, the parameters in Table 9), so the set of search space sets that the terminal monitors changes at each point in time. For example, if search space set #1 is set with an X-slot period and search space set #2 is set with a Y-slot period, and X and Y are different, the terminal will monitor both search space set #1 and search space set #2 in a given slot, and monitor either search space set #1 or search space set #2 in a given slot.

[0120] PDSCH: This section explains frequency resource allocation.

[0121] Figure 6 illustrates how a base station and a terminal transmit and receive data in a wireless communication system according to one embodiment, taking into account the downlink data channel and rate matching resources.

[0122] Figure 6 shows a downlink data channel 601 and a rate matching resource 602. The base station configures one or more rate matching resources 602 to the UE through higher-level signaling (e.g., RRC signaling). The configuration information for the rate matching resource 602 includes time-domain resource allocation information 603, frequency-domain resource allocation information 604, and periodicity information 605. If some or all of the time and frequency resources of the scheduled data channel 601 overlap with the configured rate matching resource 602, the base station rate-matches and transmits the portion of the data channel 601 that is part of the rate matching resource 602. The UE receives and decodes assuming that the data channel 601 is rate-matched in the portion of the rate matching resource 602.

[0123] The base station dynamically notifies the UE via DCI through additional configuration whether or not the data channel is rate-matched with the configured rate-matching resource portion. Specifically, the base station selects some of the configured rate-matching resources, groups the selected resources into rate-matching resource groups, and then uses a bitmap scheme to indicate via DCI whether or not the data channel has been rate-matched with each rate-matching resource group. For example, if four rate-matching resources RMR#1, RMR#2, RMR#3, and RMR#4 are configured for the UE, the base station configures RMG#1={RMR#1, RMR#2} and RMG#2={RMR#3, RMR#4}. {RMR#3, RMR#4} are configured as a rate-matching group, and two bits in the DCI field for the UE are used to indicate in bitmap form whether or not rate-matching has been performed with RMG#1 and RMG#2, respectively. For example, the base station indicates '1' when rate-matching is required and '0' when rate-matching is not required.

[0124] Figure 7 shows an example of frequency axis resource allocation for a PDSCH (physical downlink shared channel) in a wireless communication system according to one embodiment.

[0125] Figure 7 shows three frequency axis resource allocation methods that can be configured through the upper layer in an NR wireless communication system: type 0 (7-00), type 1 (7-05), and dynamic switch (7-10).

[0126] Referring to Figure 7, if a terminal is configured to use only resource type 0 through upper-layer signaling (7-00), the downlink control information (DCI) assigned to the PDSCH of that terminal includes a bitmap consisting of NRBG bits. The conditions for this will be described later. In this case, NRBG refers to the number of RBGs (resource block groups) determined by the BWP size assigned by the BWP indicator and the upper-layer parameter rbg-Size, as shown in Table 11 below, and data is sent to the RBG that is displayed as 1R in the bitmap.

[0127] [Table 11]

[0128] If a terminal is configured to use only resource type 1 through upper-layer signaling (7-05), some DCIs that assign a PDSCH to that terminal will TIFF2026102837000023.tif1114 contains frequency axis resource allocation information consisting of 1 bit. This condition will be explained again later. The base station uses this to set the starting VRB (7-20) and the length of the frequency axis resources (7-25) that are allocated sequentially from it.

[0129] If a terminal is configured to use both resource type 0 and resource type 1 through upper-layer signaling (7-10), some DCIs that assign a PDSCH to that terminal include frequency axis resource allocation information consisting of the larger of the payloads for setting resource type 0 (7-15) and the payloads for setting resource type 1 (7-20, 7-25) (7-35). This condition will be explained again later. At this time, one bit is added to the most significant bit (MSB) of the frequency axis resource allocation information in the DCI, and if the value of this bit is '0', it indicates that resource type 0 should be used, and if the value is '1', it indicates that resource type 1 should be used.

[0130] The following describes the method for allocating time-domain resources to data channels in next-generation mobile communication systems (5G or NR systems).

[0131] The base station configures tables for time-domain resource allocation information for downlink data channels (Physical Downlink Shared Channel, PDSCH) and uplink data channels (Physical Uplink Shared Channel, PUSCH) at terminals using higher-level signaling (e.g., RRC signaling). For PDSCH, a table consisting of a maximum of maxNrofDL-Allocations=16 entries is configured, and for PUSCH, a table consisting of a maximum of maxNrofUL-Allocations=16 entries is configured. In one embodiment, the time domain resource allocation information includes PDCCH-to-PDSCH slot timing (corresponding to the time interval in slot units between the time a PDCCH is received and the time a PDSCH scheduled by the received PDCCH is transmitted, denoted by K0), PDCCH-to-PUSCH slot timing (corresponding to the time interval in slot units between the time a PDCCH is received and the time a PUSCH scheduled by the received PDCCH is transmitted, denoted by K2), information on the position and length of the start symbol in which a PDSCH or PUSCH is scheduled within the slot, and the mapping type of the PDSCH or PUSCH. For example, information such as that shown in Table 12 or Table 13 below is transmitted from the base station to the terminal.

[0132] [Table 12]

[0133] [Table 13]

[0134] The base station notifies the terminal of one of the table entries for the time-domain resource allocation information described above via L1 signaling (e.g., DCI) (e.g., indicated by the 'Time-Domain Resource Allocation' field in the DCI). The terminal obtains the time-domain resource allocation information for the PDSCH or PUSCH based on the DCI received from the base station.

[0135] Figure 8 shows the time-axis resource allocation of a PDSCH in a wireless communication system according to one embodiment.

[0136] Referring to Figure 8, the base station indicates the time-axis position of the PDSCH resource by the subcarrier spacing (SCS) (μPDSCH, μPDCCH) of the data channel and control channel, the scheduling offset (K0) value, and the OFDM symbol start position (8-00) and length (8-05) within one slot, which are dynamically indicated via DCI.

[0137] Figure 9 shows the time-axis resource allocation based on the subcarrier interval of the data channel and control channel in a wireless communication system according to one embodiment.

[0138] Referring to Figure 9, when the subcarrier spacing of the data channel and the control channel are the same (9-00, μPDSCH = μPDCCH), the slot numbers for data and control are the same, so the base station and terminal generate a scheduling offset in accordance with a predetermined slot offset K0. On the other hand, when the subcarrier spacing of the data channel and the control channel are different (9-05, μPDSCH ≠ μPDCCH), the slot numbers for data and control are different, so the base station and terminal generate a scheduling offset in accordance with a predetermined slot offset K0 based on the subcarrier spacing of the PDCCH.

[0139] Next, we will explain the scheduling method for PUSCH transmissions. PUSCH transmissions are dynamically scheduled by UL grants within DCI, or they operate by configured grants Type 1 or Type 2. Dynamic scheduling instructions for PUSCH transmissions can be made using DCI format 0_0 or 0_1.

[0140] Configured grant Type 1 PUSCH transmissions are not received by UL grants within DCI, but are quasi-statically configured through the reception of configuredGrantConfig, which includes rrc-ConfiguredUplinkGrant in Table 14, via the higher-level signaling. Configured grant Type 2 PUSCH transmissions are semi-persistently scheduled by UL grants within DCI after the reception of configuredGrantConfig, which does not include rrc-ConfiguredUplinkGrant in Table 14, via the higher-level signaling. When a PUSCH transmission operates via a configured grant, the parameters applied to the PUSCH transmission are applied through configuredGrantConfig, which is the higher-level signaling in Table 14, with the exception of dataScramblingIdentityPUSCH, txConfig, codebookSubset, maxRank, and scaling of UCI-OnPUSCH, which are provided to push-Config in Table 15, which is the higher-level signaling. If the terminal is provided with transformPrecoder in configuredGrantConfig, which is the higher-level signaling in Table 14, the terminal applies tp-pi2BPSK in push-Config in Table 15 to PUSCH transmissions that operate via configured grant.

[0141] [Table 14] TIFF2026102837000027.tif118169

[0142] Next, we will explain the PUSCH transmission method. The DMRS antenna port for PUSCH transmission is the same as the antenna port for SRS transmission. PUSCH transmission follows either a codebook-based transmission method or a non-codebook-based transmission method, depending on whether the value of txConfig in push-Config in Table 14, which is the higher-level signaling, is 'codebook' or 'nonCodebook'.

[0143] As described above, PUSCH transmissions are dynamically scheduled via DCI format 0_0 or 0_1, or quasi-statically set by configured grant. When a terminal is instructed to schedule a PUSCH transmission via DCI format 0_0, the terminal uses the push-spatialRelationInfoID corresponding to the terminal-specific PUCCH resource corresponding to the minimum ID within the activated uplink BWP in the serving cell to beam-configure for the PUSCH transmission, in which case the PUSCH transmission is based on a single antenna port. The terminal does not expect to schedule a PUSCH transmission via DCI format 0_0 in a BWP where a PUCCH resource containing push-spatialRelationInfo is not configured. If the terminal does not have a txConfig in push-Config in Table 15, the terminal does not expect to be scheduled via DCI format 0_1.

[0144] [Table 15]

[0145] Next, we will describe codebook-based PUSCH transmissions. Codebook-based PUSCH transmissions are dynamically scheduled via DCI format 0_0 or 0_1 and operate quasi-statically via configured grant. When a codebook-based PUSCH is dynamically scheduled via DCI format 0_1 ​​or quasi-statically configured via configured grant, the terminal determines the precoder for the PUSCH transmission based on the SRS Resource Indicator (SRI), Transmission Precoding Matrix Indicator (TPMI), and transmission rank (number of PUSCH transmission layers).

[0146] At this time, the SRI is provided through the field "SRS resource indicator" in the DCI, or set through the higher-level signaling, srs-ResourceIndicator. A terminal has at least one SRS resource configured during a Codebook-based PUSCH transmission, and up to two. When a terminal provides an SRI through the DCI, the SRS resource indicated by that SRI refers to the SRS resource corresponding to the SRI among the SRS resources transmitted before the PDCCH containing that SRI. In addition, the TPMI and transmission rank are provided through the field "precoding information and number of layers" in the DCI, or set through the higher-level signaling, precodingAndNumberOfLayers. The TPMI is used to indicate the precoder applied to the PUSCH transmission. When a terminal has one SRS resource configured, the TPMI is used to indicate the precoder applied to that single configured SRS resource. When a terminal has multiple SRS resources configured, the TPMI is used to indicate the precoder applied to the SRS resources indicated through the SRI.

[0147] The presetr used for PUSCH transmission is selected from uplink codebooks that have the same number of antenna ports as the nrofSRS-Ports value in the higher-level signaling, SRS-Config. In codebook-based PUSCH transmission, the terminal determines the codebook subset based on TPMI and the codebookSubset in the higher-level signaling, push-Config. The codebookSubset in the higher-level signaling, push-Config, is set to one of 'fullyAndPartialAndNonCoherent', 'partialAndNonCoherent', or 'nonCoherent' based on the UE capability that the terminal reports to the base station. If the terminal reports 'partialAndNonCoherent' for UE capability, the terminal does not expect the value of the codebookSubset in the higher-level signaling to be set to 'fullyAndPartialAndNonCoherent'. Furthermore, if a terminal reports 'nonCoherent' in UE capability, the terminal does not expect the value of the higher-level signaling, codebookSubset, to be set to 'fullyAndPartialAndNonCoherent' or 'partialAndNonCoherent'. If nrofSRS-Ports in the higher-level signaling, SRS-ResourceSet, indicates two SRS antenna ports, the terminal does not expect the value of the higher-level signaling, codebookSubset, to be set to 'partialAndNonCoherent'.

[0148] The terminal is configured with one SRS resource set in the higher-level signaling SRS-ResourceSet where the usage value is set to 'codebook', and one SRS resource within that SRS resource set is indicated via SRI. If multiple SRS resources are configured within an SRS resource set where the usage value in the higher-level signaling SRS-ResourceSet is set to 'codebook', the terminal expects the nrofSRS-Ports value in the higher-level signaling SRS-Resource to be set to the same value for all SRS resources.

[0149] The terminal transmits one or more SRS resources contained within an SRS resource set where the usage value is set to 'codebook' via higher-level signaling to the base station. The base station selects one of the SRS resources transmitted by the terminal and instructs the terminal to perform a PUSCH transmission using the transmit beam information of that SRS resource. In this case, in a codebook-based PUSCH transmission, the SRI is used as information to select the index of one SRS resource and is included in the DCI. Additionally, the base station includes information in the DCI indicating the TPMI and rank that the terminal will use for the PUSCH transmission. The terminal uses the SRS resource indicated by the SRI and performs a PUSCH transmission by applying the indicated rank and the presetr indicated by the TPMI based on the transmit beam of that SRS resource.

[0150] Next, we will explain non-codebook-based push transmissions. Non-codebook-based push transmissions are dynamically scheduled via DCI format 0_0 or 0_1 and operate quasi-statically via configured grant. If at least one SRS resource is configured in an SRS resource set where the usage value in the higher-level signaling SRS-ResourceSet is set to 'nonCodebook', the terminal will schedule a non-codebook-based push transmission via DCI format 0_1.

[0151] For an SRS resource set where the usage value in the higher-level signaling SRS-ResourceSet is set to 'nonCodebook', the terminal is configured with one connected NZP CSI-RS resource (non-zero power CSI-RS). The terminal performs calculations for the precoder for SRS transmission through measurements of the NZP CSI-RS resource connected to the SRS resource set. If the difference between the last received symbol of the aperiodic NZP CSI-RS resource connected to the SRS resource set and the first symbol of the aperiodic SRS transmission at the terminal is less than 42 symbols, the UE does not expect the information for the precoder for SRS transmission to be updated.

[0152] When the value of resourceType in the higher-level signaling SRS-ResourceSet is set to 'aperiodic', the connected NZP CSI-RS is indicated by the SRS request field in DCI format 0_1 ​​or 1_1. At this time, if the connected NZP CSI-RS resource is an aperiodic NZP CSI-RS resource, the presence of the connected NZP CSI-RS is indicated if the value of the SRS request field in DCI format 0_1 ​​or 1_1 is not '00'. In this case, the DCI should not indicate cross-carrier or cross-BWP scheduling. Also, if the value of SRS request indicates the presence of an NZP CSI-RS, that NZP CSI-RS is located in the slot from which the PDCCH containing the SRS request field was sent. At this time, the TCI state set on the scheduled subcarrier is not set in QCL-TypeD.

[0153] When a periodic or semi-persistent SRS resource set is configured, the connected NZP CSI-RS is directed through associatedCSI-RS within the SRS-ResourceSet, which is the higher-level signaling. For non-codebook-based transmissions, the terminal does not expect spatialRelationInfo, which is the higher-level signaling for the SRS resource, and associatedCSI-RS within the SRS-ResourceSet, which is the higher-level signaling, to be configured together.

[0154] When multiple SRS resources are configured, the terminal determines the precoder and transmission rank applied to a PUSCH transmission based on the SRI indicated by the base station. The SRI is indicated through the SRS resource indicator field in the DCI, or configured through the higher-level signaling srs-ResourceIndicator. Similar to the Codebook-based PUSCH transmission described above, if the terminal provides the SRI through the DCI, the SRS resource indicated by that SRI refers to the SRS resource corresponding to the SRI in the SRS resource transmitted before the PDCCH containing that SRI. The terminal uses one or more SRS resources for an SRS transmission, and the maximum number of SRS resources that can be simultaneously transmitted with the same symbol within a single SRS resource set, and the maximum number of SRS resources, are determined by the UE capability reported by the terminal to the base station. In this case, the SRS resources transmitted simultaneously by the terminal occupy the same RB. The terminal configures one SRS port for each SRS resource. Only one SRS resource set with the usage value set to 'nonCodebook' in the higher-level signaling SRS-ResourceSet can be configured, and up to four SRS resources can be configured for non-Codebook-based PUSCH transmission.

[0155] The base station transmits one NZP-CSI-RS connected to the SRS resource set to the terminal. The terminal calculates the preset used when transmitting one or more SRS resources within the SRS resource set based on the measurement results upon receiving the NZP-CSI-RS. The terminal applies the preset calculated by the base station when transmitting one or more SRS resources within the SRS resource set where usage is set to 'nonCodebook'. The base station then selects one or more SRS resources from the received one or more SRS resources. In this case, for non-Codebook based PUSCH transmissions, the SRI indicates an index that can represent a combination of one or more SRS resources, and the SRI is included in the DCI. At this time, the number of SRS resources indicated by the SRI transmitted by the base station is the number of PUSCH transmission layers, and the terminal applies the preset applied to the SRS resource transmission to each layer and transmits the PUSCH.

[0156] Figure 10 shows the wireless protocol structure of the base station and terminal in a wireless communication system according to one embodiment, under the conditions of single cell, carrier aggregation, and dual connectivity.

[0157] Referring to Figure 10, the wireless protocol for the next-generation mobile communication system consists of NR SDAP (Service Data Adaptation Protocol S25, S70), NR PDCP (Packet Data Convergence Protocol S30, S65), NR RLC (Radio Link Control S35, S60), and NR MAC (Medium Access Control S40, S55) at the terminal and NR base station, respectively.

[0158] The main functions of NR SDAP (S25, S70) include some of the following functions:

[0159] - User data transfer function (transfer of user plane data)

[0160] - Mapping function between a QoS flow and a DRB for both DL and UL for uplink and downlink.

[0161] - QoS flow ID marking function for both uplink and downlink packets (marking QoS flow ID in both DL and UL packets)

[0162] - A function that maps reflective QoS flow to data bearers for uplink SDAP PDUs (reflective QoS flow to DRB mapping for the UL SDAP PDUs).

[0163] For SDAP tier devices, terminals configure via RRC messages whether to use the SDAP tier device header for each PDCP tier device, bearer, or logical channel, or whether to use the SDAP tier device's functions. If an SDAP header is configured, the NAS reflective QoS 1-bit indicator and AS reflective QoS 1-bit indicator in the SDAP header instruct the terminal to update or reset the QoS flow for uplinks and downlinks and the mapping information for data bearers. The SDAP header includes QoS flow ID information indicating QoS. QoS information is used for data processing priorities, scheduling information, etc., to support smooth service.

[0164] The main functions of NR PDCP (S30, S65) include some of the following functions:

[0165] - Header compression and decompression function (ROHC only)

[0166] - User data transmission function

[0167] - Sequential delivery of upper layer PDUs

[0168] - Out-of-sequence delivery of upper layer PDUs

[0169] - Reordering function (PDCP PDU reordering for reception)

[0170] - Duplicate detection function (Duplicate detection of lower layer SDUs)

[0171] - Retransmission function (Retransmission of PDCP SDUs)

[0172] - Encryption and deciphering functions

[0173] - Timer-based SDU deletion function (Timer-based SDU discard in uplink.)

[0174] In the above, the reordering function of the NR PDCP device refers to the function of rearranging PDCP PDUs received at lower levels based on the PDCP SN (sequence number), and includes the function of transmitting the data to higher levels in the rearranged order. Alternatively, the reordering function of the NR PDCP device includes the function of transmitting immediately without considering the procedure, the function of rearranging the procedure and recording missing PDCP PDUs, the function of reporting the status of missing PDCP PDUs to the sender, and the function of requesting retransmission of missing PDCP PDUs.

[0175] The main functions of NR RLC (S35, S60) include some of the following functions:

[0176] - Data transmission function (Transfer of upper layer PDUs)

[0177] - Sequential delivery of upper layer PDUs

[0178] - Out-of-sequence delivery of upper layer PDUs

[0179] - ARQ function (Error Correction through ARQ)

[0180] - Concatenation, segmentation, and reassembly of RLC SDUs

[0181] - Re-segmentation function (Re-segmentation of RLC data PDUs)

[0182] - Reordering function (Reordering of RLC data PDUs)

[0183] - Duplicate detection function

[0184] Error detection function (Protocol error detection)

[0185] -RLC SDU deletion function (RLC SDU discard)

[0186] -RLC re-establishment function

[0187] As described above, the in-sequence delivery function of an NR RLC device means the function of sequentially transmitting RLC SDUs received from lower levels to higher levels. The in-sequence delivery function of an NR RLC device includes the function of reassembling and transmitting RLC SDUs if they were originally received as multiple RLC SDUs, the function of rearranging received RLC PDUs based on RLC SN (sequence number) or PDCP SN (sequence number), the function of recording missing RLC PDUs after rearranging the sequence, the function of reporting the status of missing RLC PDUs to the sender, and the function of requesting retransmission of missing RLC PDUs. The in-sequence delivery function of an NR RLC device includes the function of sequentially transmitting only the RLC SDUs up to the point before the missing RLC SDU to the next level if there are missing RLC SDUs, or the function of sequentially transmitting all RLC SDUs received before the timer started to the next level if there are missing RLC SDUs but the predetermined timer has expired. Alternatively, the in-sequence delivery function of an NR RLC device includes the function of sequentially transmitting all RLC SDUs received up to the present to the next level if there are missing RLC SDUs but the predetermined timer has expired. Furthermore, as described above, RLC PDUs can be processed in the order they are received (regardless of the order of serial number and sequence number) and transmitted by the PDCP device in an out-of-sequence delivery manner. In the case of a segment, the segment stored in the buffer or received later is reconstructed into a complete single RLC PDU, processed, and then transmitted to the PDCP device. The NR RLC hierarchy does not necessarily need to include concatenation functionality; this functionality can be performed by the NR MAC hierarchy or replaced by the multiplexing functionality of the NR MAC hierarchy.

[0188] As described above, the out-of-sequence delivery function of an NR RLC device refers to the function of immediately transmitting RLC SDUs received from a lower level to a higher level regardless of the procedure. This includes the function of reassembling and transmitting RLC SDUs if they were originally received as multiple RLC SDUs, and the function of storing the RLC SN or PDCP SN of the received RLC PDU to align the procedures and record any missing RLC PDUs.

[0189] The NR MAC (S40, S55) is connected to many NR RLC hierarchical devices configured in a single terminal, and the main functions of the NR MAC include some of the following:

[0190] - Mapping function (Mapping between logical channels and transport channels)

[0191] -Multiplexing / demultiplexing of MAC SDUs

[0192] - Scheduling information reporting function

[0193] - HARQ function (Error correction through HARQ)

[0194] - Priority handling between logical channels of one UE (Logical User Interface)

[0195] - Priority handling between UEs by means of dynamic scheduling

[0196] - MBMS service identification function

[0197] -Transport format selection function

[0198] - Padding function

[0199] The NR PHY layer (S45, S50) performs channel coding and modulation of higher-level data to generate OFDM symbols and transmit them over the radio channel, or demodulates OFDM symbols received through the radio channel, channels decodes them, and transmits them to the higher layer.

[0200] The detailed structure of a wireless protocol changes in various ways depending on the carrier (or cell) operation method. For example, when a base station transmits data to a terminal based on a single carrier (or cell), the base station and terminal use a protocol structure that has a single structure for each layer, as in S00. On the other hand, when a base station transmits data to a terminal based on carrier aggregation (CA) using multiple carriers with a single TRP, the base station and terminal use a protocol structure that has a single structure up to the RLC, as in S10, but multiplexes the PHY layer through the MAC layer. As another example, when a base station transmits data to a terminal based on dual connectivity (DC) using multiple carriers with multiple TRPs, the base station and terminal use a protocol structure that has a single structure up to the RLC, as in S20, but multiplexes the PHY layer through the MAC layer.

[0201] Referring to the above-mentioned explanation of PDCCH and beam configuration, the current Rel-15 and Rel-16NR do not support repeated PDCCH transmission, making it difficult to achieve the required reliability in scenarios requiring high reliability, such as URLLC. This invention proposes a method to improve the PDCCH reception reliability at terminals by providing a method for repeated PDCCH transmission through multiple transmission points (TRPs). The specific method will be described in detail in the following embodiments.

[0202] The contents of this invention are applicable to FDD and TDD systems. Hereinafter, in this invention, upper-level signaling (or upper-layer signaling) is a signal transmission method that is transmitted from the base station to the terminal using the physical layer downlink data channel, or from the terminal to the base station using the physical layer uplink data channel, and is also called RRC signaling, PDCP signaling, or MAC (medium access control) control element (MAC control element: MAC CE).

[0203] In the present invention, when a terminal determines whether or not to apply cooperative communication, various methods can be used, such as the PDCCH to which the PDSCH to which cooperative communication is applied has a specific format, the PDCCH to which the PDSCH to which cooperative communication is applied includes a specific indicator that notifies whether or not cooperative communication is applied, the PDCCH to which the PDSCH to which cooperative communication is applied is scrambled with a specific RNTI, or the application of cooperative communication is assumed in a specific section instructed by the upper layer. For the convenience of explanation thereafter, when a terminal receives a PDSCH to which cooperative communication is applied based on conditions similar to those described above, we will refer to this as an NC-JT case.

[0204] In the present invention, determining the priority between A and B can be described in various ways, such as selecting the one with the higher priority according to a predetermined priority rule and performing the corresponding action, or omitting or dropping the action corresponding to the one with the lower priority.

[0205] In the following, the above examples will be explained through numerous embodiments of the present invention, but these embodiments are not independent, and one or more embodiments can be applied simultaneously or in combination.

[0206] A base station is at least one of the following: gNode B, gNB, eNode B, Node B, BS (Base Station), radio connection unit, base station controller, or node on the network, which is the entity responsible for allocating resources to terminals. Terminals include UE (User Equipment), MS (Mobile Station), cellular phones, smartphones, computers, or multimedia systems that perform communication functions. Hereinafter, embodiments of the present invention will be described using a 5G system as an example, but embodiments of the present invention are also applicable to other communication systems having a similar technical background or channel configuration. For example, LTE or LTE-A mobile communications and mobile communication technologies developed after 5G are included herein. Accordingly, embodiments of the present invention are also applicable to other communication systems through some modifications, as is the judgment of an ordinary artist in the art, without significantly departing from the scope of the invention. The content of the present invention is applicable to FDD and TDD systems.

[0207] Furthermore, in describing the present invention, if it is determined that a detailed explanation of related functions or configurations may unnecessarily obscure the subject matter of the invention, such detailed explanation will be omitted. Also, the terms described later are defined in consideration of the functions of the present invention and may differ depending on the intent and conventions of the user or operator. Therefore, definitions should be based on the content of this specification as a whole.

[0208] In describing the present invention below, higher-level signaling refers to signaling that corresponds to at least one or a combination of the following signalings.

[0209] -MIB(Master Information Block)

[0210] - SIB (System Information Block) or SIB X (X=1,2,…)

[0211] -RRC (Radio Resource Control)

[0212] -MAC(Medium Access Control)CE(Control Element)

[0213] Furthermore, L1 signaling is a signaling method that uses at least one or more of the following physical hierarchy channels or signaling methods.

[0214] -PDCCH (Physical Downlink Control Channel)

[0215] -DCI(Downlink Control Information)

[0216] -Terminal-Specific (UE-specific) DCI

[0217] - Group common DCI

[0218] - Common DCI

[0219] - Scheduling DCI (e.g., DCI used for scheduling downlink or uplink data)

[0220] - Non-scheduling DCI (e.g., DCI not intended for scheduling downlink or uplink data)

[0221] -PUCCH (Physical Uplink Control Channel)

[0222] -UCI(Uplink Control Information)

[0223] In the present invention, determining the priority between A and B is described in various ways, such as selecting the one with the higher priority according to a predetermined priority rule and performing the corresponding action, or omitting or dropping the action corresponding to the one with the lower priority.

[0224] In the following, the present invention will be described through numerous embodiments, which are not independent of each other, and one or more embodiments can be applied simultaneously or in combination.

[0225] According to the 3GPP® NR system, terminals use two PDSCH mapping types to determine the location of the DMRS for PDSCH reception. These two PDSCH mapping types are referred to as PDSCH mapping type A or PDSCH mapping type B for convenience.

[0226] According to PDSCH mapping type A, the first DMRS (first DMRS or front-loaded DMRS) of a PDSCH begins with the K-th symbol of the slot, where K is a value of 2 or 3 and is indicated by PBCH (Physical Broadcast Channel). For reference, the symbol corresponding to K=0 (the 0th symbol) is the first symbol of the slot. For a terminal to receive a PDSCH with PDSCH mapping type A, the time domain of the PDSCH must contain the K-th symbol. That is, the time domain allocation of a PDSCH with PDSCH mapping type A must have a starting symbol (S) of one of 0, 1, 2, or 3, and a length (L) of one of 3, 4, ..., 14. Table 16 shows the possible combinations of starting symbol (S) and length (L) when PDSCH mapping type A is used.

[0227] According to PDSCH mapping type B, the first DMRS (first DMRS or front-loaded DMRS) of a PDSCH is located at the first symbol of the scheduled PDSCH. Unlike PDSCH mapping type A, in PDSCH mapping type B, the position of the first DMRS is determined by the time resource allocation of the scheduled PDSCH. A time domain allocation for a PDSCH with PDSCH mapping type B has a start symbol (S) of one symbol from 0, 1, ..., 12, and a length (L) of one value from 2, 3, ..., 13. Table 16 shows the possible combinations of start symbol (S) and length (L) when PDSCH mapping type B is used.

[0228] [Table 16]

[0229] Here, we have explained the PDSCH mapping type, but PUSCH also uses two PUSCH mapping types (PUSCH mapping type A and PUSCH mapping type B). For convenience, in the following explanation, PDSCH or PUSCH will be abbreviated and referred to simply as the mapping type.

[0230] The terminal receives time domain information and mapping type instructions through the DCI format TDRA (time domain resource assignment) field.

[0231] The base station configures the terminal with a TDRA table used by the DCI format. The TDRA table has multiple rows. Each row contains at least the following information:

[0232] - TDRA row index -Time domain information (S, L) included in the TDRA row -TDRA row mapping type - The slot offset value (K0 value) that receives PDSCH or the slot offset value (K2 value) that transmits PUSCH, based on the time domain information of the TDRA row.

[0233] The terminal receives the index of the TDRA row in the TDRA field in DCI format. Therefore, the terminal obtains information about the time domain information, mapping type, etc., of the TDRA row corresponding to the TDRA row index.

[0234] Mapping type A and mapping type B have different use cases. For example, in mapping type A, the first DMRS of a PDSCH (or PUSCH) always starts at the Kth symbol of the slot, regardless of the PDSCH's (or PUSCH's) time-domain resource allocation. Therefore, even if different terminals schedule PDSCHs (or PUSCHs) with different time-domain resource allocations, the position of the first DMRS of the PDSCH (or PUSCH) will be the same. Thus, it may be suitable for multiplexing between different terminals, i.e., MU-MIMO (multi-user MIMO). In the case of mapping type B, if different terminals receive (transmit) PDSCHs (or PUSCHs) with different starting positions, the first DMRS positions of the PDSCHs (or PUSCHs) of the different terminals will be different. In mapping type B, since the DMRS is always located at the first symbol of the scheduled PDSCH (or PUSCH), the terminal receives the DMRS fastest and performs channel estimation or PDSCH decoding (the base station receives the DMRS fastest and performs channel estimation or PUSCH decoding). Therefore, mapping type B is suitable for environments requiring high-speed PDSCH (or PUSCH) reception (transmission) and decoding. Consequently, different mapping types have different DMRS configurations.

[0235] Each terminal has different DMRS settings for each mapping type.

[0236] DMRS configuration includes at least the following three pieces of information:

[0237] -dmrs-Type: Set to either DMRS configuration type 1 or 2.

[0238] -maxLength: Sets the maximum number of symbols that DMRS can occupy.

[0239] -dmrs-AdditionalPosition: Configure additional DMRSs other than the first DMRS (first DMRS or front-loaded DMRS).

[0240] The three pieces of information in the DMRS configuration are set differently for each mapping type. For example, dmrs-Type is set to 1 for mapping type A, and dmrs-Type is set to 2 for mapping type B. For example, maxLength is set to 2 for mapping type A, and maxLength is set to 1 for mapping type B. For example, dmrs-AdditionalPosition for mapping type A and dmrs-AdditionalPosition for mapping type B are different from each other.

[0241] This section explains the Antenna port field.

[0242] The terminal requires information about the DMRS port for PDSCH reception or PUSCH transmission. This information is indicated in the Antenna port field of the DCI format used to schedule PDSCH or PUSCH.

[0243] The Antenna port field refers to one row in the Antenna port table. Here, a row in the Antenna port table contains at least the following information:

[0244] -Antenna port table row index - An index of DMRS port(s) corresponding to rows in the Antenna port table. - The number of DMRS symbols corresponding to rows in the Antenna port table (exists if maxLength is 2 or greater) - Number of data or CDM (code division multiplexing) groups corresponding to rows in the Antenna port table.

[0245] Terminals receive different DMRS settings depending on the mapping type. For example, mapping type A is configured with the first DMRS setting, and mapping type B is configured with the second DMRS setting. Therefore, the first antenna port table for a PDSCH (or PUSCH) scheduled for mapping type A is different from the second antenna port table for a PDSCH (or PUSCH) scheduled for mapping type B. Furthermore, the two antenna port tables have different numbers of rows. The two antenna port tables may have different DMRS port(s) indexes in the same row, different numbers of DMRS symbols, different data, or different numbers of CDM groups, etc.

[0246] The terminal receives an instruction for a row in one of two antenna port tables in DCI format. More specifically, the terminal determines the length of the antenna port field in DCI format based on the maximum number of rows in each of the two antenna port tables. For example, suppose the first antenna port table contains a total of 32 rows and the second antenna port table contains 64 rows. In this case, the terminal determines the length of the antenna port field based on the maximum value of 64, i.e., ceil(log2(64)) = 6 bits.

[0247] The terminal determines the mapping type of the scheduled PDSCH (or PUSCH) through the TDRA field in DCI format. The terminal determines the antenna port table based on the DMRS setting of the mapping type. It also determines the number of bits required based on the number of rows in the determined antenna port table. The number of bits required is equal to or less than the number of bits in the antenna port. The terminal obtains the index of the row in the antenna port table from some of the bits (e.g., LSB, least significant bits) of the number of bits required in the antenna port field. Through this process, the terminal obtains the mapping type of the scheduled PDSCH (or PUSCH) and DMRS-related information (such as the index of the DMRS port(s), the number of DMRS symbols, data, or the number of CDM groups).

[0248] For reference, in the case of PUSCH, the antenna port table is determined according to the DMRS setting of the PUSCH mapping type and the PUSCH rank.

[0249] Table 17 shows the Antenna port field for DCI format 0_1 ​​used for PUSCH scheduling, and Tables 18 to 37 are the corresponding antenna port tables.

[0250] [Table 17] TIFF2026102837000031.tif50170

[0251] [Table 18]

[0252] [Table 19]

[0253] Table 20

[0254] Table 21

[0255] Table 22

[0256] Table 23

[0257] Table 24

[0258] Table 25

[0259] Table 26

[0260] Table 27

[0261] Table 28

[0262] Table 29

[0263]

Table 30

[0264]

Table 31

[0265]

Table 32

[0266]

Table 33

[0267]

Table 34

[0268]

Table 35

[0269]

Table 36

[0270]

Table 37

[0271] Table 38 is the Antenna port field of DCI format 1_1 for scheduling PDSCH, and Tables 39 to 46 are the corresponding Antenna port tables.

[0272]

Table 38

[0273] Table 39

[0274] Table 40

[0275] Table 41

[0276] Table 42

[0277] Table 43

[0278] Table 44

[0279] Table 45 TIFF2026102837000060.tif128170

[0280] Table 46 TIFF2026102837000062.tif132170

[0281] Assume that the PDSCH mapping type of one of the terminals is set to dmrs-Type=1 and maxLength=2 in the DMRS settings. In this case, the corresponding Antenna port table is Table 42. The terminal receives a DCI format that schedules a PDSCH, which is the PDSCH mapping type, and the DCI format includes an Antenna port field. The Antenna port field points to one of the 32 rows (value 0 to value 31) in Table 42. For reference, referring to Table 42, if only one codeword is activated in the PDSCH, one of the 32 rows (value 0 to value 31) is pointed to. If two codewords are activated simultaneously in the PDSCH, one of the four rows (value 0 to value 3) out of the 32 rows is pointed to, and the other rows (value 3 to value 31) are not pointed to.

[0282] Assume that the PUSCH mapping type of one of the terminals is set to dmrs-Type = 2 and maxLength=2 in the DMRS settings. In this case, the corresponding Antenna port table is one of Tables 34 to 37. Here, one Antenna port table is determined by rank. Assume rank=3. In this case, the Antenna port table is Table 36. The terminal receives a DCI format that schedules a PUSCH, which is the PUSCH mapping type, and the DCI format includes an Antenna port field. The Antenna port field indicates one of the 32 rows (value 0 to value 31) in Table 36. For reference, referring to Table 36, one of the 6 rows (value 0 to value 5) out of the 32 rows is indicated. The other rows (value 6 to value 31) are not indicated.

[0283] In subsequent embodiments, the terminal includes multiple scheduling information for at least one TDRA row in the TDRA table, where one of the scheduling information for the TDRA row includes mapping type A and the other scheduling information includes both mapping type B. That is, when the terminal receives an instruction for a TDRA row, it receives (or sends) a PDSCH (or PUSCH) with mapping type A using one scheduling information and receives (or sends) a PDSCH (or PUSCH) with mapping type B using the other scheduling information.

[0284] In the following embodiments, for the sake of explanation, “TDRA row with different mapping types” means that a TDRA row contains multiple scheduling pieces of information, one of which contains mapping type A and the other contains both mapping type B.

[0285] This section explains the procedure for using the uplink PTRS.

[0286] The terminal sets phaseTrackingRS, an upper-layer parameter for PTRS, on the upper-layer parameter DMRS-UplinkConfig. When the base station transmits a PUSCH, the terminal transmits a phase tracking reference signal (PTRS) for phase tracking on the uplink channel. The procedure for the terminal to transmit UL PTRS is determined by whether or not transform precoding is performed when transmitting a PUSCH. If transform precoding is performed and the transformPrecoderEnabled area is set in the upper-layer parameter PTRS-UplinkConfig, the sampleDensity in the transformPrecoderEnabled area indicates the sample density threshold shown in NRB0 to NRB4 in Table 47. If transform precoding is performed and the transformPrecoderEnabled area is set in the upper-layer parameter PTRS-UplinkConfig, the terminal determines the PT-RS group pattern for the resource NRBs scheduled according to Table 47. Additionally, when transform precoder is applied to a PUSCH transmission, the number of bits in the PTRS-DMRS association area, which indicates the association between PTRS and DMRS in DCI format 0_1 ​​or 0_2, becomes 0.

[0287] [Table 47]

[0288] If transform precoding is not applied to a PUSCH transmission and the upper-layer parameter phaseTrackingRS is set, the terminal indicates NRB0 or ​​NRB1 of frequencyDensity in the transformPrecoderDisabled area of ​​the upper-layer parameter PTRS-UplinkConfig, and indicates ptrs-MCS1 to ptrs-MCS3 of timeDensity. The terminal determines the PT-RS density in the time domain (LPT-RS) and the PT-RS density in the frequency domain (KPT-RS) based on the MCS (lMCS) and RB (NRB) of the scheduled PUSCH, as shown in Tables 48-1 and 48-2. In Table 48-1, ptrs-MCS4 is not explicitly stated in the upper-layer parameters, but the base station and terminal know it to be 29 or 28 from the configured MCS table.

[0289] [Table 48-1]

[0290] [Table 48-2]

[0291] If the Transform precoder is not applied to PUSCH transmissions and PTRS-UplinkConfig is set, the base station instructs the terminal to use a 2-bit 'PTRS-DMRS association' field in DCI format 0_1 ​​or 0_2 to indicate the association between PTRS and DMRS. The instructed 2-bit PTRS-DMRS association field is applied to Table 49-1 or Table 49-2 depending on the maximum number of PTRS ports set in maxNrofPorts in the upper-layer parameter PTRS-UplinkConfig. If the maximum PTRS port value is 1, the terminal determines the association between PTRS and DMRS using Table 49-1 and the 2 bits instructed in the PTRS-DMRS association field, and transmits PTRS according to the determined association. If the maximum PTRS port value is 2, the terminal determines the association between PTRS and DMRS using Table 49-2 and the 2 bits instructed in the PTRS-DMRS association field, and transmits PTRS according to the determined association.

[0292] [Table 49-1]

[0293] [Table 49-2]

[0294] The DMRS ports in Tables 49-1 and 49-2 are determined through the 'Antenna ports' area, which is pointed to in the same DCI as the DCI that points to the PTRS-DMRS association, and through the tables determined by the higher-layer parameter settings. If the transform precoder is not set in the higher-layer settings of PUSCH, and dmrs-Type is set to 1 and maxLength to 2 for DMRS, and the rank of PUSCH is 2, the terminal determines the DMRS ports through the tables for 'Antenna port(s)' as shown in Table 50 and the bits pointed to in the Antenna ports area. If PUSCH supports a non-codebook-based system, the terminal determines the rank value by referring to the SRI area, which is pointed to in the same DCI as the DCI containing the 'Antenna ports' area (i.e., if the SRI area does not exist, the Rank is considered to be 1). If the rank supports a codebook-based system, the terminal determines the rank value by referring to the TPMI area, which is pointed to in the same DCI as the DCI containing the 'Antenna ports' area. Table 50 is an example of an Antenna port table referenced when configuring PUSCH as described, but is not limited to this. If PUSCH is configured with other parameters, the DMRS port will be determined by the 'Antenna port' table resulting from the configuration and the bits in the 'Antenna ports' area indicated to DCI.

[0295] [Table 50]

[0296] The 1st scheduled DMRS to 4th scheduled DMRS in Table 49-1 are defined by sequentially mapping the DMRS ports indicated in the 'Antenna ports' area of ​​the DCI and the 'antenna port' table based on higher-layer settings. For example, if the bits in the 'Antenna ports' area of ​​the DCI are 0001 and the DMRS ports are determined by referring to Table 50, the scheduled DMRS ports will be 0 and 1, with DMRS port 0 being defined as the 1st scheduled DMRS and DMRS port 1 as the 2nd scheduled DMRS. The same applies to DMRS ports determined by different 'Antenna ports' area bits and different 'antenna port' tables based on higher-layer settings. The terminal determines one DMRS port to associate with the PTRS port by referring to the bits indicated in the PTRS-DMRS association within the DCI among the DMRS ports defined as described above, and transmits PTRS through the determined DMRS port.

[0297] In Table 49-2, DMRS ports sharing PTRS port 0 and DMRS ports sharing PTRS port 1 are defined by codebook-based PUSCH transmissions or non-codebook-based PUSCH transmissions. When a terminal transmits a PUSCH on a partial-coherent or non-coherent codebook basis, the uplink layers transmitted to PUSCH antenna ports 1000 and 1002 are associated with PTRS port 0, and the uplink layers transmitted to PUSCH antenna ports 1001 and 1003 are associated with PTRS port 1. More specifically, if layer 3:TPMI=2 is selected for codebook-based PUSCH transmissions, the first layer is transmitted to PUSCH antenna ports 1000 and 1002 and is therefore associated with PTRS port 0, the second layer is transmitted to PUSCH antenna port 1001, and the third layer is transmitted to PUSCH antenna port 1002 and is therefore associated with PTRS port 1. The three layers represent their respective DMRS ports. The DMRS port for the first layer corresponds to '1st DMRS port which shares PTRS port 0' in Table 49-2, the DMRS port for the second layer corresponds to '1st DMRS port which shares PTRS port 1' in Table 49-2, and the DMRS port for the third layer corresponds to '2nd DMRS port which shares PTRS port 1' in Table 49-2. Similarly, the DMRS port associated with PTRS port 0 and the DMRS port associated with PTRS port 1 are determined by different layer numbers and TPMIs. When a terminal sends a PUSCH on a non-Codebook basis, the SRI and Antenna ports instructed to DCI distinguish between the DMRS port associated with PTRS port 0 and the DMRS port associated with PTRS port 1.More specifically, an SRS resource included in an SRS resource set with usage set to 'nonCodebook' is configured via the upper-layer parameter ptrs-PortIndex to determine whether it is associated with PTRS port 0 or PTRS port 1. The base station indicates the SRS resource for non-Codebook-based PUSCH transmission using the SRI. The port of each indicated SRS resource is mapped one-to-one with each PUSCH DMRS port. The relationship between the PUSCH DMRS port and the PTRS port is determined by the upper-layer parameter ptrs-PortIndex of the SRS resource mapped to the DMRS port. More specifically, if SRS resources 1-4 included in an SRS resource set with usage set to nonCodebook have ptrs-PortIndex set to n0, n0, n1, and n1 respectively, and the SRI instructs that PUSCH be transmitted through SRS resources 1, 2, and 4, and DMRS ports 0, 1, and 2 are indicated in the Antenna ports area, then the ports of each SRS resource 1, 2, and 4 are mapped to DMRS ports 0, 1, and 2. Then, according to the ptrs-PortIndex in the SRS resource, DMRS ports 0 and 1 are associated with PTRS port 0, and DMRS port 2 is associated with PTRS port 1. Therefore, in Table 49-2, DMRS port 0 corresponds to '1st DMRS port which shares PTRS port 0', DMRS port 1 corresponds to '2nd DMRS port which shares PTRS port 0', and DMRS port 2 corresponds to '1st DMRS port which shares PTRS port 1'. Similarly, the DMRS port associated with PTRS port 0 and the DMRS port associated with PTRS port 1 are determined by different patterns of ptrs-PortIndex settings in the SRS resource and other SRI values. The terminal determines the association between DMRS ports and PTRS ports for two PTRS ports as described above.The terminal refers to the MSB bit of the PTRS-DMRS association among the many DMRS ports associated with each PTRS port to determine the DMRS port associated with PTRS port 0. The terminal then refers to the LSB bit to determine the DMRS port associated with PTRS port 1 and transmits the PTRS.

[0298] [Multi-PDSCH / PUSCH Scheduling]

[0299] A new scheduling method was introduced in 3GPP's (3rd generation partnership project) Rel-17 NR (new raido). This invention relates to a new scheduling method. The new scheduling methods introduced in Rel-17 NR are 'Multi-PDSCH scheduling', in which one DCI schedules one or more PDSCHs, and 'Multi-PUSCH scheduling', in which one DCI schedules one or more PUSCHs. Here, each PDSCH or PUSCH transmits a different transmit block (TB). By using Multi-PDSCH scheduling and Multi-PUSCH scheduling, the base station does not schedule multiple DCIs to schedule each of the multiple PDSCHs or PUSCHs to the terminal, thus reducing the overhead of the downlink control channel. However, the size of the DCI increases because one DCI for Multi-PDSCH scheduling and Multi-PUSCH scheduling must contain scheduling information for multiple PDSCHs or PUSCHs. Therefore, when Multi-PDSCH scheduling and Multi-PUSCH scheduling are configured on a terminal, a method is needed for the terminal to interpret DCI in a favorable way.

[0300] Although this specification describes Multi-PDSCH scheduling, the concept of the technology proposed in this invention can also be used in Multi-PUSCH scheduling.

[0301] The base station can configure Multi-PDSCH scheduling on the terminal. The base station can explicitly configure Multi-PDSCH scheduling on the terminal using a higher-level signal (e.g., the RRC (radio resource control) signal). Alternatively, the base station can implicitly configure Multi-PDSCH scheduling on the terminal using a higher-level signal (e.g., the RRC signal).

[0302] The base station sets a TDRA (time domain resource assignment) table for multi-PDSCH scheduling on the terminal using a higher-level signal (e.g., RRC signal) as follows: The TDRA table contains one or more rows. Up to N_row rows can be set, and each row is assigned a unique index. The unique index is one value from 1, 2, ..., N_row. Here, N_row is preferably 64, but is not limited to this. Each row is set with one or more scheduling information. When one scheduling information is set in a row, the row schedules one PDSCH. That is, when a row is indicated, it means that single-PDSCH scheduling is indicated. When multiple scheduling information is set in a row, the multiple scheduling information sequentially schedules multiple PDSCHs. That is, when a row is indicated, it indicates that multi-PDSCH scheduling is indicated.

[0303] The scheduling information includes at least one of the K0, SLIV, or PDSCH mapping types. That is, when Multi-PDSCH scheduling is indicated, a row contains multiple scheduling information entries (K0, SLIV, PDSCH mapping type). The Nth scheduling information entry (K0, SLIV, PDSCH mapping type) is the scheduling information for the Nth PDSCH. For reference, a single row contains a maximum of N_pdsch scheduling information entries (K0, SLIV, PDSCH mapping type). Here, N_pdsch is preferably 8, but is not limited to this. For example, a single row schedules a maximum of 8 PDSCHs.

[0304] Here, K0 indicates the slot in which the PDSCH is scheduled, showing the slot difference between the slot in which the PDCCH that sends the DCI scheduling the PDSCH receives the information and the slot in which the PDSCH is scheduled. That is, if K0=0, the PDSCH and PDCCH are in the same slot. SLIV (starting and length indictor value) indicates the index of the symbol in which the PDSCH starts within a single slot and the number of consecutive symbols to which the PDSCH is assigned. The PDSCH mapping type indicates information about the position of the PDSCH's first DMRS (front-loaded DMRS). In the case of PDSCH mapping type A, the PDSCH's first DMRS (front-loaded DMRS) starts at the third or fourth symbol in slot, and in the case of PDSCH mapping type B, the PDSCH's first DMRS (front-loaded DMRS) starts at the first symbol in which the PDSCH is scheduled.

[0305] When setting rows in the TDRA table using higher-level signals, some of the scheduling information, such as K0, SLIV, and PDSCH mapping type, is omitted. In this case, the omitted information is interpreted as a default value or a pre-set value. For example, if K0 is omitted, the value of K0 is interpreted as 0. In addition, when setting rows in the TDRA table, information other than K0, SLIV, and PDSCH mapping type is set.

[0306] In the following explanation, the terminal is configured for Multi-PDSCH scheduling. Here, Multi-PDSCH scheduling means that at least one row in the TDRA table contains multiple scheduling entries. For reference, the other row in the TDRA table contains one scheduling entry. Therefore, even if a terminal is configured for Multi-PDSCH scheduling, it will be instructed to either Single-PDSCH scheduling or Multi-PDSCH scheduling according to the TDRA field of the received DCI. In other words, Multi-PDSCH scheduling is instructed when the row in the TDRA table instructed by the DCI contains multiple scheduling entries, and Single-PDSCH scheduling is instructed when the row in the TDRA table instructed by the DCI contains one scheduling entry.

[0307] In the case of a Single-PDSCH scheduling instruction, one PDSCH is scheduled, and that single PDSCH requires information such as MCS (modulation coding scheme), NDI (new data indicator), RV (redundancy version), and HPN (HARQ process number). Therefore, the DCI (Digital Control Indicator) that instructs the scheduling of a Single-PDSCH must include information such as MCS, NDI, RV, and HPN for that single PDSCH. More specifically,

[0308] A DCI that instructs a Single-PDSCH to schedule includes one MCS field. The MCS specified in the MCS field (i.e., modulation scheme and channel code code rate) applies to the single PDSCH that the DCI schedules.

[0309] - A DCI that instructs a Single-PDSCH to schedule includes a 1-bit NDI field. The NDI value is obtained from the 1-bit NDI field, and based on the NDI value, it is determined whether one PDSCH should send a new transmit block or retransmit a previous transmit block.

[0310] - A DCI that instructs a single PDSCH to schedule includes a 2-bit RV field. The RV value is obtained from the 2-bit RV field, and the redundant version of the single PDSCH is determined based on the RV value.

[0311] - The DCI for scheduling a single PDSCH includes one HPN field. One HPN field is 4 bits (for reference, if the terminal supports up to 32 HARQ processes, the HPN field is extended to 5 bits, but for explanatory convenience of this invention, we assume 4 bits). One HARQ process ID is indicated through one HPN field. One HARQ process ID is the HARQ process ID of the scheduled PDSCH.

[0312] -When instructing Multi-PDSCH scheduling, multiple PDSCHs are scheduled, so each PDSCH requires information such as MCS, NDI, RV, and HPN. Therefore, the DCI instructing Multi-PDSCH scheduling must include information such as MCS, NDI, RV, and HPN for each PDSCH being scheduled. More specifically,

[0313] A DCI that instructs multi-PDSCH scheduling includes one MCS field. The MCS (i.e., modulation scheme and channel code code rate) specified in the MCS field applies similarly to all PDSCHs that the DCI schedules. In other words, a DCI that performs multi-PDSCH scheduling does not schedule different PDSCHs using different MCSs.

[0314] - The DCI indicating multi-PDSCH scheduling includes a K-bit NDI field, where K is the maximum number of scheduling information entries in each row of the TDRA table. For example, if the TDRA table has two rows, with the first row containing 4 scheduling information entries and the second row containing 8, then K=8. The k-th bit of the K-bit NDI field indicates the NDI value of the PDSCH corresponding to the k-th scheduling information entry. That is, the k-th PDSCH obtains the NDI value from the k-th bit of the K-bit NDI field and determines, based on the NDI value, whether the k-th PDSCH should send a new transmit block or retransmit the previous transmit block.

[0315] - A DCI indicating multi-PDSCH scheduling includes a K-bit RV field. The k-th bit of the K-bit RV field indicates the RV value of the PDSCH corresponding to the k-th scheduling information. That is, the k-th PDSCH obtains the RV value from the k-th bit of the K-bit RV field and determines the redundancy version of the k-th PDSCH based on the RV value.

[0316] - A DCI instructing Multi-PDSCH scheduling includes one HPN field. One HPN field is 4 bits (for reference, if the terminal supports up to 32 HARQ processes, the HPN field is extended to 5 bits, but in the embodiments of this invention, for explanatory convenience, we assume 4 bits). One HARQ process ID is indicated through one HPN field. One HARQ process ID is the HARQ process ID of the first PDSCH among the PDSCHs scheduled by the DCI instructing Multi-PDSCH scheduling. Here, the first PDSCH corresponds to the first scheduling information. Thereafter, the HPN of the PDSCH is sequentially incremented by 1. That is, for the second PDSCH (corresponding to the second scheduling information), the HPN is the HARQ process ID of the first PDSCH incremented by 1. For reference, if the HARQ process ID exceeds the maximum number of HARQ process IDs set on the terminal (numOfHARQProcessID), a modulo operation is performed. In other words, if the HARQ process ID specified in DCI is 'x', the HARQ process ID of the k-th PDSCH is determined as follows:

[0317] HPN of the k-th PDSCH = (x + k - 1) modulo numOfHARQProcessID

[0318] As mentioned above, when instructing Single-PDSCH scheduling, the DCI includes a 1-bit NDI field or a 2-bit RV field, and when instructing Multi-PDSCH scheduling, the DCI includes a K-bit NDI field or a K-bit RV field. For reference, Single-PDSCH scheduling instructions and Multi-PDSCH scheduling instructions are indicated in the TDRA field of the DCI (i.e., whether it is a Single-PDSCH or Multi-PDSCH scheduling instruction is determined by the number of scheduling information entries in the row of the indicated TDRA field). Therefore, a single DCI must support both Single-PDSCH and Multi-PDSCH scheduling. If the length of the DCI for Single-PDSCH scheduling instructions and the length of the DCI for Multi-PDSCH scheduling instructions are different, '0' is added (padding) to the shorter DCI to make them the same length.

[0319] The terminal's DCI interpretation process is as follows: The terminal receives the DCI. At this time, the length of the DCI is assumed to be the larger of the length of the DCI for Single-PDSCH scheduling instructions and the length of the DCI for Multi-PDSCH scheduling instructions. The terminal knows the position of the TDRA field in the DCI. The position of the TDRA field is the same for DCI for Single-PDSCH scheduling instructions and DCI for Multi-PDSCH scheduling instructions. The terminal determines through the TDRA field whether the received DCI is for Single-PDSCH scheduling instructions or Multi-PDSCH scheduling instructions. If the number of scheduling information items in the row of the indicated TDRA field is one, the terminal determines it is a Single-PDSCH scheduling instruction. If the number of scheduling information items in the row of the TDRA field is two or more, the terminal determines it is a Multi-PDSCH scheduling instruction. If the terminal determines it is a Single-PDSCH scheduling instruction, it interprets the DCI according to its determination. In other words, the NDI field is interpreted as 1 bit and the RV field as 2 bits. When the terminal determines that it is a Multi-PDSCH scheduling instruction, it interprets the DCI accordingly. In other words, it interprets the NDI field as K bits and the RV field as K bits. For reference, the position of other fields in the DCI changes depending on the length of the NDI field or the RV field. Therefore, although the bit length of the other fields is the same, their position in the DCI differs depending on whether it is a Single-PDSCH scheduling instruction or a Multi-PDSCH scheduling instruction.

[0320] Figure 11 shows a PDSCH scheduling method according to one embodiment.

[0321] -The first row (row 0) of the TDRA table contains four scheduling information entries (K0, SLIV, PDSCH mapping type). Here, the first SLIV is SLIV00, the second SLIV is SLIV01, the third SLIV is SLIV02, and the fourth SLIV is SLIV03. Therefore, when a terminal receives the instruction in the first row (row 0) of the TDRA table, it determines that Multi-PDSCH scheduling has been instructed.

[0322] -The second row (row 1) of the TDRA table contains two pieces of scheduling information (K0, SLIV, PDSCH mapping type). Here, the first SLIV is SLIV10 and the second SLIV is SLIV11. Therefore, when a terminal receives the instruction in the second row (row 1) of the TDRA table, it determines that Multi-PDSCH scheduling has been instructed.

[0323] -The third row (row 2) of the TDRA table contains one piece of scheduling information (K0, SLIV, PDSCH mapping type). Here, SLIV is set to SLIV20. Therefore, when a terminal receives the instruction in the third row (row 2) of the TDRA table, it determines that Single-PDSCH scheduling has been instructed.

[0324] Figure 11(a) shows the case where the terminal receives the instruction for the first row (row 0) of the TDRA table. The TDRA field of the DCI received by the terminal at PDCCH1100 indicates the first row (row 0) of the TDRA table. As a result, the terminal receives four PDSCHs based on the four scheduling information (K0, SLIV, PDSCH mapping type) in the first row (row 0). The terminal determines the symbol for receiving the first PDSCH1101 based on the first SLIV, SLIV00; the symbol for receiving the second PDSCH1102 based on the second SLIV, SLIV01; the symbol for receiving the third PDSCH1102 based on the third SLIV, SLIV02; and the symbol for receiving the fourth PDSCH1103 based on the fourth SLIV, SLIV03. Each of the four PDSCHs has a unique HARQ process ID. That is, the first PDSCH has HPN0 as its HARQ process ID, the second PDSCH has HPN1 as its HARQ process ID, the third PDSCH has HPN2 as its HARQ process ID, and the fourth PDSCH has HPN3 as its HARQ process ID. Here, the HPN field in the DCI indicates the HARQ process ID of the first PDSCH, and the HARQ process IDs of the remaining PDSCHs are determined based on the HARQ process ID of the first PDSCH. For example, the DCI indicates HPN0=0 as the HARQ process ID of the first PDSCH. In this case, the HARQ process ID of the second PDSCH is HPN1=1, the HARQ process ID of the third PDSCH is HPN1=2, and the HARQ process ID of the fourth PDSCH is HPN1=3.

[0325] Figure 11(b) shows the case where the terminal receives an instruction for the second row (row 1) of the TDRA table. The TDRA field of the DCI received by the terminal at PDCCH1110 indicates the second row (row 1) of the TDRA table. This causes the terminal to receive two PDSCHs based on the two scheduling pieces of information (K0, SLIV, PDSCH mapping type) in the second row (row 1). The terminal determines the symbol for receiving the first PDSCH1111 based on the first SLIV, SLIV10, and determines the symbol for receiving the second PDSCH1112 based on the second SLIV, SLIV11. Each of the two PDSCHs has a unique HARQ process ID. That is, the first PDSCH has HARQ process ID HPN0, and the second PDSCH has HARQ process ID HPN1. Here, the HFN field in the DCI indicates the HARQ process ID of the first PDSCH, and the HARQ process IDs of the remaining PDSCHs are determined based on the HARQ process ID of the first PDSCH. For example, if the HARQ process ID of the first PDSCH in the DCI is HPN0=0, then the HARQ process ID of the second PDSCH will be HPN1=1.

[0326] Figure 11(c) shows the case where the terminal receives an instruction for the third row (row 2) of the TDRA table. The TDRA field of the DCI received by the terminal at PDCCH1120 indicates the third row (row 2) of the TDRA table. This allows the terminal to receive one PDSCH based on one scheduling piece of information (K0, SLIV, PDSCH mapping type) in the third row (row 2). Based on one SLIV, SLIV20, it determines the symbol for receiving one PDSCH1121. The HARQ process ID of one PDSCH, i.e., HPN0, is indicated in the DCI. For example, the HPN field of the DCI indicates HPN0=0, which is the HARQ process ID of the first PDSCH.

[0327] Figure 12 shows the DCI for Single-PDSCH scheduling and Multi-PDSCH scheduling according to one embodiment.

[0328] Referring to Figures 12(a) and 12(b), the terminal determines the position of the TDRA field 1200 in the received DCI. The position is the same for both Single-PDSCH scheduling DCIs and Multi-PDSCH scheduling DCIs. The terminal determines from the value of the TDRA field whether the received DCI is a DCI that indicates Single-PDSCH scheduling or a DCI that indicates Multi-PDSCH scheduling.

[0329] If the row corresponding to the value of the TDRA field in the received DCI contains one piece of scheduling information (K0, SLIV, PDSCH mapping type) (for example, the third row (row 2) of the TDRA table), the terminal interprets it as a DCI for Single-PDSCH scheduling, as shown in Figure 12(a).

[0330] Referring to Figure 12(a), the DCI for Single-PDSCH scheduling includes a 5-bit MCS field 1205, a 1-bit NDI field 1210, a 2-bit RV field 1215, and a 4-bit HARQ field 1220. The DCI for Single-PDSCH scheduling also includes additional fields beyond those mentioned above. For example, the DCI may include an Antenna port(s) field 1225 or a DMRS sequence initialization field 1230. Furthermore, if the DCI for Single-PDSCH scheduling is shorter than the DCI for Multi-PDSCH scheduling, it may include additional padding bits 1235.

[0331] If the row corresponding to the value of the TDRA field in the received DCI contains two or more scheduling information fields (K0, SLIV, PDSCH mapping type) (for example, the first row (row 0) to the third row (row 1) of the TDRA table), the terminal interprets it as a Multi-PDSCH scheduling DCI, as shown in Figure 12(b). Referring to Figure 12(b), the Multi-PDSCH scheduling DCI includes the 5-bit MCS field 1255, the K-bit NDI fields (1260, 1261), the K-bit RV fields (1262, 1263), and the 4-bit HARQ field 1270. In addition, the Multi-PDSCH scheduling DCI includes fields other than those mentioned above. For example, the DCI may further include the Antenna port(s) field 1275 or the DMRS sequence initialization field 1280. For reference, Figure 12(b) shows a DCI where up to two PDSCHs are scheduled. Here, the 2-bit NDI fields (1260, 1261) are shown separately, but they may be combined into a single 2-bit field. Also, in Figure 12(b), the 2-bit RV fields (1262, 1263) are shown separately, but they may be combined into a single 2-bit field.

[0332] For reference, referring to Figure 12(a) or Figure 12(b), padding bits 1235 were added to the DCI for Single-PDSCH scheduling, assuming that the length of the DCI indicating Single-PDSCH scheduling is shorter than the length of the DCI indicating Multi-PDSCH scheduling. If the length of the DCI indicating Single-PDSCH scheduling is longer than the length of the DCI indicating Multi-PDSCH scheduling, padding bits are added to the DCI indicating Multi-PDSCH scheduling.

[0333] Hereafter, unless otherwise specified, this specification assumes that PDSCH transmits a single codeword. If a terminal is configured to transmit two codewords, unless otherwise specified, the DCI fields refer to the first codeword.

[0334] Figure 13 illustrates the HARQ-ACK transmission of one or more PDSCHs that DCI schedules when DCI instructs Multi-PDSCH scheduling according to one embodiment.

[0335] The base station sets one or more K1 values ​​for the terminal. This is called the K1 set. The DCI that directs Multi-PDSCH scheduling includes an indicator that points to one K1 value in the K1 set. More specifically, the DCI includes a PDSCH-to-HARQ_feedback timing indicator field, which is up to 3 bits. This field points to one K1 value in the K1 set.

[0336] The terminal determines which slot will send the HARQ-ACK for multiple PDSCHs based on a single K1 value and the slot in which the last PDSCH of the multiple PDSCHs is scheduled. For reference, the HARQ-ACK for all PDSCHs scheduled to one DCI is sent through one PUCCH in the slot that sends the HARQ-ACK. The slot that sends the HARQ-ACK for multiple PDSCHs is the slot located K1 slots after the slot in which the last PDSCH is scheduled. That is, the PUCCH containing the HARQ-ACK for multiple PDSCHs is sent in the slot K1 slots after the slot in which the last PDSCH is scheduled.

[0337] Referring to Figure 13, we assume that the DCI received by the terminal via PDCCH1300 indicates row 0 of the TDRA table as shown in Figure 12, and that PDSCH is scheduled in slots n-5, n-4, n-3, and n-2 according to row 0 of the TDRA table. We also assume that the terminal is indicated by a K1 value of 2. In this case, the terminal determines that slot n, which is two slots after slot n-2 (the last slot on which PDSCH is scheduled) by the K1 value, is the slot to send the HARQ-ACK. That is, the terminal sends the HARQ-ACK information for PDSCH1301 in slot n-5, PDSCH1302 in slot n-4, PDSCH1303 in slot n-3, and PDSCH1304 in slot n-2 using PUCCH1305 in slot n.

[0338] This section explains multi-cell multi-PDSCH / PUSCH scheduling.

[0339] A new scheduling method has been introduced in Rel-18 NR (new raido) of 3GPP (registered trademark) (3rd generation partnership project). The aforementioned Multi-PDSCH / PUSCH scheduling involved one DCI scheduling one or more PDSCHs or PUSCHs to one cell. The new scheduling method in Rel-18 NR involves one DCI scheduling a PDSCH or PUSCH to each of multiple cells. This scheduling method is called multi-cell multi-PDSCH / PUSCH scheduling.

[0340] A terminal receives instructions for the cell where a PDSCH or PUSCH is scheduled through a single DCI. For example, a single DCI might be designated for Cell A and Cell B. The terminal also receives scheduling information for Cell A (K0 / SLIV / PDSCH mapping type for PDSCH, K2 / SLIV / PUSCH mapping type for PUSCH) and Cell B. Based on the scheduling information designated for Cell A and Cell B, the terminal receives a PDSCH or transmits a PUSCH.

[0341] Here, each cell's scheduling information is assigned a different mapping type.

[0342] The present invention will be described below based on multi-PDSCH / PUSCH scheduling, but the present invention can also be applied to multi-cell multi-PDSCH / PUSCH scheduling.

[0343] The following description of the present invention addresses the problem in multi-PDSCH / PUSCH scheduling where multiple PDSCHs or PUSCHs have different mapping types, and a different antenna port table is applied to each mapping type. In multi-cell multi-PDSCH / PUSCH scheduling, the same multiple PDSCHs or PUSCHs in the same cells have different mapping types. Therefore, the problem arises where a different antenna port table is applied to each mapping type. Furthermore, in multi-cell multi-PDSCH / PUSCH scheduling, even if PDSCHs or PUSCHs in different cells have the same mapping type, different antenna port tables are applied depending on the scheduled cell. Therefore, the following description will discuss the problem of different antenna port tables due to different mapping types, which is linked to the problem of different antenna port tables due to different cells.

[0344] Through multiple PDSCH scheduling and multiple PUSCH scheduling settings, a terminal has multiple scheduling entries set in a single TDRA (Time Domain Resource Assignment) row, each of which has an SLIV (Starting and Length Indication Value) and mapping type. Therefore, the terminal receives instructions for TDRA rows containing scheduling information of different mapping types through a single DCI.

[0345] Different mapping types are configured with different DMRS configuration information. When the DMRS configuration information is different, the antenna port table for indicating the DMRS port is different. The DCI format for scheduling PDSCH or PUSCH includes an antenna port field to indicate one row in the antenna port table. However, as mentioned above, the antenna port field in the DCI format is used to indicate one row in one antenna port table. However, if a terminal is indicated with a TDRA row that has multiple scheduling entries for different mapping types, the terminal needs to receive an indication for one row in each of the two antenna port tables. The method for doing this is described below.

[0346] The DMRS configuration constraints are as follows:

[0347] In an embodiment of the present invention, the terminal expects mapping type A and mapping type B to use the same antenna port table. Here, in order to use the same antenna port table, the terminal is configured from the higher layer with the same DMRS type (dmrs-Type) and DMRS maximum length (maxLength). The base station configures the terminal with the same DMRS type (dmrs-Type) and DMRS maximum length (maxLength).

[0348] When a TDRA table is configured containing TDRA rows with different mapping types, the terminal expects mapping type A and mapping type B to use the same antenna port table. That is, when a TDRA table is configured containing TDRA rows with different mapping types, the terminal expects mapping type A and mapping type B to have the same DMRS type (dmrs-Type) and DMRS maximum length (maxLength).

[0349] If a base station configures a terminal with a TDRA table containing TDRA rows of different mapping types, the base station must configure the terminal so that mapping type A and mapping type B use the same antenna port table. In other words, if a base station configures a terminal with a TDRA table containing TDRA rows of different mapping types, the base station must configure the terminal so that the DMRS type (dmrs-Type) and DMRS maximum length (maxLength) for mapping type A and mapping type B are equal.

[0350] When a TDRA table is configured that does not contain TDRA rows of different mapping types, the terminal expects the antenna port tables for mapping type A and mapping type B to be the same or different. In other words, when a TDRA table is configured that does not contain TDRA rows of different mapping types, the terminal expects the DMRS type (dmrs-Type) and DMRS maximum length (maxLength) for mapping type A and mapping type B to be the same or different. To put it another way, when a terminal is configured with a TDRA table that does not contain TDRA rows of different mapping types, there are no configuration constraints on the DMRS type (dmrs-Type) and DMRS maximum length (maxLength) for mapping type A and mapping type B.

[0351] When a base station configures a terminal's TDRA table that does not contain TDRA rows of different mapping types, the base station configures the terminal to use either the same or different antenna port tables for mapping type A and mapping type B. In other words, when a base station configures a terminal's TDRA table that does not contain TDRA rows of different mapping types, the base station configures the terminal to use either the same or different DMRS types (dmrs-Type) and DMRS maximum length (maxLength) for mapping type A and mapping type B. To put it another way, when a base station configures a terminal's TDRA table that does not contain TDRA rows of different mapping types, the base station is free to configure the DMRS types (dmrs-Type) and DMRS maximum length (maxLength) for mapping type A and mapping type B without any configuration constraints.

[0352] In one embodiment, if at least one row in the TDRA table configured on the terminal is a TDRA of a different mapping type, the DMRS type (dmrs-Type) and DMRS maximum length (maxLength) of mapping type A and mapping type B should be the same. This also affects other TDRA rows in the TDRA table.

[0353] For example, suppose the TDRA table contains scheduling information where the first TDRA row is mapping type A, and the second TDRA row contains scheduling information where the second TDRA row is mapping type B. In the existing operation (without the operation of the first embodiment), the base station sets different DMRS types (dmrs-Type) or DMRS maximum lengths (maxLength) for mapping type A and mapping type B at the terminal. Therefore, the PDSCH (or PUSCH) scheduled in the first TDRA row and the PDSCH (or PUSCH) scheduled in the second TDRA row have DMRS with different DMRS types (dmrs-Type) or DMRS maximum lengths (maxLength). However, according to the operation of one embodiment, the PDSCH (or PUSCH) scheduled in the first TDRA row and the PDSCH (or PUSCH) scheduled in the second TDRA row must always have DMRS with the same DMRS type (dmrs-Type) or DMRS maximum length (maxLength). This makes it difficult to set a DMRS appropriate for the base station's mapping type.

[0354] To solve this problem, the following embodiments can be considered.

[0355] The terminal receives additional DMRS settings only for TDRA lines with different mapping types in higher-level signals (e.g., RRC signals). Each DMRS setting includes at least the DMRS type (dmrs-Type) or DMRS maximum length (maxLength). The terminal receives three DMRS settings as follows:

[0356] 1. DMRS Configuration: DMRS configuration for TDRA lines containing only scheduling information of Mapping type A.

[0357] 2nd DMRS Configuration: DMRS configuration for TDRA lines containing only scheduling information, which is Mapping type B.

[0358] Third DMRS configuration: DMRS configuration for TDRA lines including scheduling information of Mapping type A and scheduling information of Mapping type B.

[0359] For reference, the first DMRS setting is the DMRS setting configured for Mapping type A ('dmrs-DownlinkForPDSCH-MappingTypeA' for PDSCH mapping type A, and 'dmrs-UplinkForPUSCH-MappingTypeA' for PUSCH mapping type A), the second DMRS setting is the DMRS setting configured for Mapping type B ('dmrs-DownlinkForPDSCH-MappingTypeB' for PDSCH mapping type B, and 'dmrs-UplinkForPUSCH-MappingTypeB' for PUSCH mapping type B), and the third DMRS setting is the newly configured DMRS setting.

[0360] When the terminal receives a DCI format, it performs the following actions:

[0361] The terminal obtains the index of the TDRA row from the TDRA field in the received DCI format. It also obtains the scheduling information and the mapping type of the scheduling information contained in the TDRA row.

[0362] If the TDRA row contains only scheduling information where mapping type A, the terminal assumes the first DMRS configuration. Therefore, the terminal determines the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) by the first DMRS configuration and uses the antenna port table based on the DMRS type (dmrs-Type) or DMRS maximum length (maxLength).

[0363] If the TDRA row contains only scheduling information with mapping type B, the terminal assumes a second DMRS configuration. Therefore, the terminal determines the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) based on the second DMRS configuration and uses the antenna port table based on the DMRS type (dmrs-Type) or DMRS maximum length (maxLength).

[0364] If a TDRA line contains scheduling information with mapping type A and scheduling information with mapping type B, the terminal assumes a third DMRS configuration. Therefore, the terminal determines the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) by the third DMRS configuration and uses an antenna port table based on the DMRS type (dmrs-Type) or DMRS maximum length (maxLength). Here, mapping type A and mapping type B scheduled for a TDRA line use the same antenna port table. Therefore, the DMRS configurations for mapping type A and mapping type B have the same DMRS port(s), the same number of DMRS symbols, and the same number of CDM groups without data. However, the actual DMRS location to be transmitted is determined differently depending on mapping type A and mapping type B.

[0365] The terminal interprets the `antenna port` field based on the `antenna port` table.

[0366] The interpretation of the antenna port field is as follows:

[0367] If the number of rows in the antenna port table corresponding to the first DMRS configuration is N1, the required number of bits is 'X1(X1=ceil(log2(N1))).

[0368] If the number of rows in the antenna port table corresponding to the second DMRS setting is N2, the number of bits required is X2 (X2 = ceil(log2(N2))).

[0369] Third, if the number of rows in the antenna port table corresponding to the DMRS setting is N3, the number of bits required is X3 (X3 = ceil(log2(N3))).

[0370] The length of the antenna port field in the DCI format monitored by the terminal is determined as follows:

[0371] If only one of the three DMRS settings is configured on the terminal, the length of the antenna port field is one of X1 bits, X2 bits, or X3 bits, depending on the configured DMRS setting. That is, if only the first DMRS setting is configured on the terminal, the length of the antenna port field is X1 bits. If only the second DMRS setting is configured on the terminal, the length of the antenna port field is X2 bits. If only the second DMRS setting is configured on the terminal, the length of the antenna port field is X2 bits.

[0372] If only two of the three DMRS settings are configured on the terminal, the length of the antenna port field is the maximum number of bits required by the two configured DMRS settings, i.e., max{Xn,Xm} bits, where n and m are determined by the configured DMRS settings. Specifically, if the first and second DMRS settings are configured on the terminal, the length of the antenna port field is max{X1,X2} bits. If the first and third DMRS settings are configured on the terminal, the length of the antenna port field is max{X1,X3} bits. If the second and third DMRS settings are configured on the terminal, the length of the antenna port field is max{X2,X3} bits.

[0373] If all three DMRS settings are configured on the terminal, the length of the antenna port field is the maximum number of bits required for the three configured DMRS settings, i.e., max{X1,X2,X3} bits.

[0374] When a terminal interprets the antenna port field based on the antenna port table, not all bits of the antenna port field are needed. For example, if a terminal has all three DMRS settings configured, the DCI format monitored by the terminal will include an antenna port field of max{X1,X2,X3} bits. If the TDRA field in the DCI format contains only scheduling information where the indicated TDRA row is mapping type A, then the LSB (least significant bit) X1 bits of the max{{X1,X2,X3} bits antenna port field are needed, but the MSB (most significant bit) max{X1,X2,X3}-X1 bits are not. Therefore, the terminal assumes that the MSB max{X1,X2,X3}X1 bits of the antenna port field are padded with '0' and interprets the antenna port field based on this assumption.

[0375] If the TDRA field in DCI format indicates that the TDRA row contains only scheduling information of mapping type B, then the LSB X2 bits of the max{X1,X2,X3} bit antenna port field are required, but the MSB max{X1,X2,X3}-X2 bits are not. Therefore, the terminal assumes that the MSB max{X1,X2,X3}-X2 bits of the antenna port field are padded with '0' and interprets the antenna port field based on this assumption.

[0376] If the TDRA field in DCI format indicates that the TDRA row contains scheduling information of mapping type A and scheduling information of mapping type B, then the LSB X3 bits of the max{X1,X2,X3} bits in the antenna port field are required, but the MSB max{X1,X2,X3}-X3 bits are not. Therefore, the terminal assumes that the MSB max{X1,X2,X3}-X3 bits of the antenna port field are padded with '0' and interprets the antenna port field based on this assumption.

[0377] The third DMRS setting is the same as either the first or second DMRS setting. That is, when a device receives the third DMRS setting, it receives the same setting as either the first or second DMRS setting, but it does not receive a setting different from the first or second DMRS settings. Through this restriction, a device can receive a maximum of two different DMRS settings.

[0378] The third DMRS configuration requires a new higher-level signal (e.g., an RRC signal). This introduces design and overhead for the higher-level signal. Methods to mitigate this problem are described below.

[0379] The terminal does not receive higher-level signal settings for the third DMRS setting. Instead, the third DMRS setting is determined from the following information:

[0380] -Method 1: The terminal always assumes that the third DMRS setting is the same as the first DMRS setting. The terminal uses the DMRS setting for TDRA rows that contains only scheduling information of mapping type A as the third DMRS setting. In other words, the terminal determines the DMRS for mapping type B, which is scheduled to TDRA rows of a different mapping type, using the DMRS setting for mapping type A, i.e., the DMRS type (dmrs-Type) or DMRS maximum length (maxLength). Therefore, the terminal uses the antenna port table for mapping type A with respect to mapping type B, which is scheduled to TDRA rows of a different mapping type. Here, the DMRS location for mapping type B follows the same method as mapping type B.

[0381] -Second method: The terminal always assumes that the third DMRS setting is the same as the second DMRS setting. That is, the terminal uses the DMRS setting for TDRA rows that contains only scheduling information of mapping type B as the third DMRS setting. In other words, the terminal determines the DMRS using the DMRS setting for mapping type B with respect to mapping type A that is scheduled to TDRA rows of different mapping types, i.e., the DMRS type (dmrs-Type) or DMRS maximum length (maxLength). Therefore, the terminal uses the antenna port table for mapping type B with respect to mapping type A that is scheduled to TDRA rows of different mapping types. Here, the DMRS location for mapping type A follows the same method as mapping type A.

[0382] -In the third method, the terminal assumes that the third DMRS setting is the same as either the first DMRS setting or the second DMRS setting based on the mapping type of one of the scheduling pieces of scheduling information that is scheduled to TDRA lines of different mapping types.

[0383] For example, the terminal assumes that the third DMRS setting is the same as either the first or second DMRS setting based on the mapping type of the earliest scheduling information among the scheduling information scheduled to TDRA lines of different mapping types. If the mapping type of the earliest scheduling information is mapping type A, the terminal assumes that the DMRS setting for mapping type A, i.e., the first DMRS setting, is the same as the third DMRS setting. If the mapping type of the earliest scheduling information is mapping type B, the terminal assumes that the DMRS setting for mapping type B, i.e., the second DMRS setting, is the same as the third DMRS setting.

[0384] Here, the earliest scheduling information is replaced with the latest scheduling information. Here, the earliest scheduling information is the earliest scheduling information in terms of time.

[0385] According to one embodiment, multiple PDSCH / PUSCH scheduling programs introduce the same mapping type constraint.

[0386] If the antenna port table corresponding to mapping type A and the antenna port table corresponding to mapping type B are different for a terminal, the terminal expects the mapping type of the scheduling information contained in the TDRA row to be the same. If the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) for mapping type A and the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) for mapping type B are different for a terminal, the terminal expects the mapping type of the scheduling information contained in the TDRA row to be the same.

[0387] Furthermore, if the terminal has TDRA rows with different mapping types set in the TDRA table, it assumes that the antenna port table corresponding to mapping type A and the antenna port table corresponding to mapping type B are the same. If the terminal has TDRA rows with different mapping types set in the TDRA table, it assumes that the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) for mapping type A and the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) for mapping type B are the same.

[0388] In other words, the terminal does not expect that the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) of mapping type A and the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) of mapping type B are different from each other, and that TDRA rows of different mapping types will be set in the TDRA table. The terminal does not expect that the antenna port table corresponding to mapping type A and the antenna port table corresponding to mapping type B are different from each other, and that TDRA rows of different mapping types will be set in the TDRA table.

[0389] If a base station configures a terminal to have different DMRS types (dmrs-Type) or DMRS maximum length (maxLength) for mapping type A and different DMRS types (dmrs-Type) or DMRS maximum length (maxLength) for mapping type B, the base station will always set the mapping type of the scheduling information included in the TDRA line to be the same.

[0390] When a base station sets up TDRA rows with different mapping types in the TDRA table for a terminal, the base station must set the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) for mapping type A to be the same as the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) for mapping type B.

[0391] In other words, the base station does not configure the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) of mapping type A to be different from the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) of mapping type B, so that TDRA rows of different mapping types are included in the TDRA table.

[0392] The terminal determines the location and length of the DMRS based on the DMRS settings in the mapping type, because the scheduled PDSCH (or PUSCH) in the TDRA field of the received DCI format always has the same mapping type. The terminal also determines one antenna port table based on the DMRS settings in the mapping type. One row in that antenna port table is indicated by the antenna port field.

[0393] According to one embodiment, the Antenna port field refers to each row in two antenna port tables.

[0394] If a terminal sets up TDRA rows with different mapping types in the TDRA table, the terminal assumes that the respective Antenna port fields for mapping type A and mapping type B are present in the DCI format being monitored. Alternatively, the terminal assumes that the Antenna port field in the DCI format being monitored contains bits for mapping type A and bits for mapping type B.

[0395] The length of the Antenna port field is determined by X1 + X2 bits.

[0396] The MSB (1 bit) of the Antenna port field is used to indicate a single row in the antenna port table based on the DMRS configuration for mapping type A. The LSB (2 bits) of the Antenna port field is used to indicate a single row in the antenna port table based on the DMRS configuration for mapping type B. Conversely, the MSB (1 bit) can be used for mapping type B and the LSB (2 bits) can be used for mapping type A.

[0397] For example, if the terminal sets TDRA rows of different mapping types in the TDRA table according to the third embodiment, the terminal obtains X1 bits to indicate the antenna port table of mapping type A and X2 bits to indicate the antenna port table of mapping type B in the DCI format to be monitored. Since the terminal receives an indication for one row of the antenna port table of mapping type A with X1 bits and an indication for one row of the antenna port table of mapping type B with X2 bits, it is possible to freely specify antenna ports.

[0398] In the third embodiment, X1+X2 bits are not always required in the DCI format monitored by the terminal. For example, if the TDRA line indicated by the TDRA field in the DCI format received by the terminal contains scheduling information for only one mapping type, then X1+X2 bits are not required. For this reason, the antenna port field in the DCI format monitored by the terminal is determined as follows:

[0399] According to one method, if the TDRA table configured on the terminal contains at least one TDRA row with a different mapping type, the DCI format monitored by the terminal will contain X1+X2 bits. That is, even if the terminal receives an antenna port field of X1+X2 bits, it will always receive an antenna port field of X1+X2 bits in the TDRA row indicated by the TDRA field in the DCI format. In this case, the index value of the row in the antenna port table for one mapping type can be obtained from the antenna port field received by the terminal as follows:

[0400] The terminal assumes X1+X2 bits are in binary, converts them to decimal, and then considers the decimal value to be the index of the row in the antenna port table. When the number of rows in the antenna port table is Ni, and the number of bits required to indicate this is X=i(Xi=ceil(log2(Ni))) bits, the terminal assumes that the MSB of the antenna port field is padded with bits '0' (X1+X2-Xi). Here, i=1 if one mapping type is mapping type A, and 2 if it is mapping type B.

[0401] If one mapping type is mapping type A, the MSB x1 bits of the antenna port field are used to find the row index of the antenna port table for mapping type A. If one mapping type is mapping type B, the LSB x2 bits of the antenna port field are used to find the row index of the antenna port table for mapping type B. If one mapping type is mapping type A, the terminal assumes that the LSB x2 bits of the antenna port field are padded with '0'. If one mapping type is mapping type B, the terminal assumes that the MSB x1 bits of the antenna port field are padded with '0'.

[0402] According to another method, the length of the antenna port field changes according to the mapping type of the TDRA line indicated by the TDRA field in the DCI format received by the terminal. If the TDRA line indicated by the TDRA field in the DCI format received by the terminal contains scheduling information for only one mapping type, the terminal assumes that the received DCI format contains an antenna port field of max{X1,X2} bits. That is, if the TDRA line indicated by the TDRA field in the DCI format received by the terminal contains scheduling information for only one mapping type, the terminal assumes that it contains an antenna port field with the same number of bits as the existing one.

[0403] If the TDRA line indicated by the TDRA field in the DCI format received by the terminal contains scheduling information of mapping type A and scheduling information of mapping type B, the terminal assumes that the received DCI format contains an antenna port field of X1+X2 bits. That is, if the TDRA line indicated by the TDRA field in the DCI format received by the terminal contains scheduling information of mapping type A and scheduling information of mapping type B, the terminal assumes that it contains an antenna port field of X1+X2 bits according to the third embodiment of the present invention.

[0404] According to another method, the length of the antenna port field changes according to the number of scheduling information entries in the TDRA line indicated by the TDRA field in the DCI format received by the terminal. If the TDRA line indicated by the TDRA field in the DCI format received by the terminal contains only one scheduling information entry, the terminal assumes that the received DCI format contains an antenna port field of max{X1,X2} bits. That is, if the TDRA line indicated by the TDRA field in the DCI format received by the terminal contains only one scheduling information entry, the terminal assumes that it contains an antenna port field of the same number of bits as the existing one.

[0405] If the TDRA line indicated by the TDRA field in the DCI format received by the terminal contains multiple scheduling information, the terminal assumes that the received DCI format contains an antenna port field of X1+X2 bits. That is, if the TDRA line indicated by the TDRA field in the DCI format received by the terminal contains multiple scheduling information, the terminal assumes that it contains an antenna port field of X1+X2 bits according to the third embodiment of the present invention.

[0406] The terminal determines or assumes the length of the antenna port field according to the TDRA line indicated by the TDRA field of the received DCI format. When monitoring the DCI format, the terminal needs to know the length of the DCI format in advance. Therefore, if the length of the DCI format differs depending on the TDRA line indicated by the TDRA field, the terminal adjusts to the length of the longest DCI format. That is, the terminal adds some bits to the shorter DCI format to match the length of the longest DCI format. The terminal adds some bits to the LSB of the shorter DCI format to match the length of the longest DCI format. The some bits are '0'.

[0407] According to one embodiment, the Antenna port field indicates one or more rows in the antenna port combination table.

[0408] The terminal receives a new antenna port combination table configuration from the base station, where the antenna port field points to one row in the antenna port combination table.

[0409] The new antenna port combination table is defined as follows:

[0410] Each row in the new antenna port combination table has its own unique index.

[0411] Each row in the new antenna port combination table will have a first index and a second index. Here, the first index is the row index of one of the rows in the antenna port table with mapping type A. Here, the second index is the row index of one of the rows in the antenna port table with mapping type B.

[0412] When a new antenna port combination table is set up, the terminal retrieves rows from the antenna port table as follows:

[0413] The terminal obtains the index of the row in the antenna port combination table from the antenna port field. The terminal obtains the first and second indexes set on the row in the antenna port combination table. The terminal considers the first index to be the index of the antenna port table for mapping type A, and the second index to be the index of the antenna port table for mapping type B. Therefore, the terminal considers the row corresponding to the first index of the antenna port table for mapping type A to be indicated as a row in the antenna port table for mapping type A, and the row corresponding to the second index of the antenna port table for mapping type B to be indicated as a row in the antenna port table for mapping type B.

[0414] The Antenna port combination table applies to all TDRA rows or to specific TDRA rows.

[0415] If the terminal has an antenna port combination table configured, information about the DMRS and antenna port for all TDRA rows of PDSCH (or PUSCH) can be obtained from the antenna port combination table.

[0416] More specifically, if the TDRA field in the DCI format received by the terminal indicates that the TDRA row contains only scheduling information of mapping type A, the terminal determines the row in the antenna port combination table from the antenna port field, and then determines the row in the antenna port table for mapping type A based on the first index of the antenna port combination table row. In this case, the second index corresponding to mapping type B, which is not scheduled, is ignored.

[0417] If the TDRA field in the DCI format received by the terminal indicates that the TDRA row contains only scheduling information of mapping type B, the terminal determines the row in the antenna port combination table from the antenna port field, and then determines the row in the antenna port table for mapping type B based on the second index of the antenna port combination table row. In this case, the first index corresponding to mapping type A, which is not scheduled, is ignored.

[0418] If the TDRA field in the DCI format received by the terminal indicates that the TDRA row contains scheduling information of mapping type A and scheduling information of mapping type B, the terminal determines the row of the antenna port combination table from the antenna port field, and then determines the row of the antenna port table for mapping type A based on the first index of the antenna port combination table row and the row of the antenna port table for mapping type B based on the second index.

[0419] Here, the antenna port table for mapping type A is an antenna port table based on the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) set in mapping type A, and the antenna port table for mapping type B is an antenna port table based on the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) set in mapping type B.

[0420] When using the first method, the length of the antenna port field is determined by the number of rows set in the antenna port combination table. If the number of rows set in the antenna port combination table is Ncomb, the antenna port field is ceil(log2(Ncomb)) bits.

[0421] If an antenna port combination table is configured, the terminal will use the antenna port combination table if it indicates TDRA rows with different mapping types, and will use the existing antenna port table (i.e., the antenna port table with DMRS settings configured for mapping type A, and the antenna port table with DMRS settings configured for mapping type B) if it indicates TDRA rows with scheduling information for only one mapping type.

[0422] More specifically, if the TDRA row indicated by the TDRA field in the DCI format received by the terminal contains only scheduling information of mapping type A, the terminal obtains an index of the row in the antenna port table determined by the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) of mapping type A from the antenna port field. The terminal then obtains the antenna port information from the row in the antenna port table of the index.

[0423] If the TDRA field in the DCI format received by the terminal indicates that the TDRA row contains only scheduling information of mapping type B, the terminal obtains an index of the row in the antenna port table determined by the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) of mapping type B from the antenna port field. The terminal then retrieves the antenna port information from the row in the antenna port table of the index.

[0424] If the TDRA field in the DCI format received by the terminal indicates that the TDRA row contains scheduling information of mapping type A and scheduling information of mapping type B, the terminal determines the row of the antenna port combination table from the antenna port field, and then determines the row of the antenna port table for mapping type A based on the first index of the antenna port combination table row and the row of the antenna port table for mapping type B based on the second index.

[0425] The length of the antenna port field is determined by the number of rows in the antenna port table for mapping type A, the number of rows in the antenna port table for mapping type B, and the number of rows set in the antenna port combination table. If the number of rows set in the antenna port combination table is Ncomb, and the number of bits used to indicate a row in the antenna port combination table is Xcomb=ceil(log2(Ncomb)), then for example, the length of the antenna port field is determined as follows: The length of the antenna port field in DCI format is max{X1,X2,Xcomb} bits. Here, the length of the antenna port field is fixed regardless of the mapping type included in the TDRA row indicated by the TDRA field in DCI format. In addition or alternatively, the length of the antenna port field in DCI format is max{X1,X2} bits or Xcomb bits. If the TDRA field in DCI format received by the terminal indicates that the TDRA line contains scheduling information for only one mapping type, the length of the Antenna port field is max{X1,X2} bits. If the TDRA field in DCI format received by the terminal indicates that the TDRA line contains scheduling information for only one mapping type, the length of the Antenna port field is Xcomb bits.

[0426] When an antenna port combination table is configured, the terminal uses the antenna port combination table if it indicates a TDRA row containing multiple scheduling information entries, and uses the existing antenna port table (i.e., the antenna port table based on the DMRS settings configured for mapping type A, or the antenna port table based on the DMRS settings configured for mapping type B) if it indicates a TDRA row containing only one scheduling information entry.

[0427] More specifically, if the TDRA row indicated by the TDRA field in the DCI format received by the terminal contains only scheduling information of mapping type A, the terminal obtains an index of the row in the antenna port table determined by the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) of mapping type A from the antenna port field. The terminal then obtains the antenna port information from the row in the antenna port table of the index.

[0428] If the TDRA field in the DCI format received by the terminal indicates that the TDRA row contains only scheduling information of mapping type B, the terminal obtains an index of the row in the antenna port table determined by the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) of mapping type B from the antenna port field. The terminal then retrieves the antenna port information from the row in the antenna port table of the index.

[0429] If the TDRA field in the DCI format received by the terminal indicates that the TDRA row contains multiple scheduling information, the terminal determines the row in the antenna port combination table from the antenna port field, and then determines the row in the antenna port table for mapping type A based on the first index of the antenna port combination table row and the row in the antenna port table for mapping type B based on the second index.

[0430] The length of the antenna port field is determined by the number of rows in the antenna port table for mapping type A, the number of rows in the antenna port table for mapping type B, and the number of rows set in the antenna port combination table. If the number of rows set in the antenna port combination table is Ncomb, and the number of bits used to indicate a row in the antenna port combination table is Xcomb=ceil(log2(Ncomb)), then the length of the antenna port field is determined as follows: The length of the antenna port field in DCI format is max{X1,X2,Xcomb} bits. Here, the length of the antenna port field is fixed regardless of the number of scheduling information entries in the TDRA row indicated by the TDRA field in DCI format. Additionally or alternatively, the length of the antenna port field in DCI format is max{X1,X2} bits or Xcomb bits. If the TDRA field in the DCI format received by the terminal indicates a TDRA line containing only one scheduling information, the length of the Antenna port field is max{X1,X2} bits. If the TDRA line indicated by the DCI format received by the terminal indicates a TDRA line containing multiple scheduling information, the length of the Antenna port field is Xcomb bits.

[0431] According to one embodiment, the terminal is configured with an antenna port combination table for each rank to specify the PUSCH antenna port from the base station. More specifically, the terminal is configured with an antenna port combination table for rank 1 PUSCH, an antenna port combination table for rank 2 PUSCH, an antenna port combination table for rank 3 PUSCH, and an antenna port combination table for rank 4 PUSCH. Here, the first index of the antenna port combination table for rank r (r=1,2,3,4) points to the row in the antenna port table corresponding to the DMRS setting of mapping type A and rank r (r=1,2,3,4), and the second index points to the row in the antenna port table corresponding to the DMRS setting of mapping type B and rank r (r=1,2,3,4).

[0432] The terminal has an antenna port combination table configured for specifying the PDSCH antenna port from the base station, categorized by the number of activated codewords. More specifically, the terminal has an antenna port combination table for PDSCHs with one activated codeword (hereinafter referred to as the first table) and an antenna port combination table for PDSCHs with two activated codewords (hereinafter referred to as the second table). When the PDSCH scheduled in the received DCI contains one activated codeword, the terminal uses the first table. That is, the first index of the first table points to the row in the antenna port table corresponding to the DMRS setting of mapping type A, and obtains DMRS information (DMRS port(s), number of DMRS symbols, number of CDM groups without data) when the number of activated codewords in the row is one. The second index of the first table points to the row in the antenna port table corresponding to the DMRS setting of mapping type B, and retrieves DMRS information (DMRS port(s), number of DMRS symbols, number of DMRS CDM groups without data) when the number of activated codewords in the row is 1. Similarly, the terminal uses the second table if the PDSCH scheduled in the received DCI contains 2 activated codewords. That is, the first index of the second table points to the row in the antenna port table corresponding to the DMRS setting of mapping type A, and retrieves DMRS information (DMRS port(s), number of DMRS symbols, number of DMRS CDM groups without data) when the number of activated codewords in the row is 1. The second index of the second table points to the row in the antenna port table corresponding to the DMRS setting of mapping type B, and retrieves DMRS information (DMRS port(s), number of DMRS symbols, number of DMRS CDM groups without data) when the number of activated codewords in the row is 1.

[0433] According to one embodiment, the antenna port field value is expected to indicate the same DMRS information.

[0434] When a terminal receives TDRA lines with different mapping types for different DCI formats, it expects the same antenna port field value to indicate the same DMRS information, even if different antenna port tables are used for each mapping type. Here, the same DMRS information is the same DMRS port(s), the same number of front-load symbols, or the same number of DMRS CDM group(s) without data. When a base station receives TDRA lines with different mapping types for different DCI formats and different antenna port tables are used for each mapping type, the base station does not expect the same antenna port field value to indicate the same DMRS information.

[0435] Identical DMRS information includes entries that are identical in at least one of the following: DMRS port(s), number of front-load symbols, or number of DMRS CDM group(s) without data. For example, identical DMRS information includes entries with the same DMRS port(s).

[0436] In other words, if a terminal receives a DCI format that indicates a TDRA line with a different mapping type, and different antenna port tables are used for each mapping type, the terminal will not expect an antenna port field value to indicate other DMRS information. Similarly, if a base station transmits a DCI format that indicates a TDRA line with a different mapping type, and different antenna port tables are used for each mapping type, the base station will not expect an antenna port field value to indicate other DMRS information.

[0437] Even if different antenna port tables are used for different mapping types, rows with the same index in both antenna port tables will have the same DMRS port. For example, if Table 41 (for dmrs-Type=1, maxLength=2) and Table 43 (for dmrs-Type=2, maxLength=1) are set for PDSCH mapping types A and B, then when only one codeword is activated, it will be confirmed that rows 0 through 10 of the two tables have the same DMRS port(s), the same number of front-load symbols, and the same number of DMRS CDM group(s) without data. Therefore, if either row is indicated, the terminal will determine the DMRS and antenna port information for mapping type A and mapping type B.

[0438] According to one embodiment, the value of the Antenna port field is expected to be applied to the antenna port tables of two mapping types, respectively.

[0439] When the terminal is directed to a TDRA row with a different mapping type, it applies the value of the antenna port field to the antenna port tables for each of the two mapping types.

[0440] The terminal expects the value of the antenna port field to point to a valid row (a non-reserved row) in the antenna port table for the two mapping types. That is, if the value of the antenna port field points to a value that is not valid in any one of the antenna port tables for the two mapping types, the terminal will determine this to be an error case and ignore the DCI format containing the antenna port field.

[0441] The terminal assumes that scheduling information for a mapping type that uses the antenna port table will not be scheduled if the value of the antenna port field indicates that one of the antenna port tables for the two mapping types is a non-valid row (reserved row).

[0442] For example, when the TDRA field in the DCI format received by the terminal indicates that the TDRA row contains scheduling information of mapping type A and scheduling information of mapping type B, the terminal applies the value indicated by the antenna port field to the respective antenna port table to determine the row. That is, the terminal applies the value indicated by the antenna port field to the antenna port table of mapping type A to determine the DMRS information and antenna port information of mapping type A, and applies the value indicated by the antenna port field to the antenna port table of mapping type B to determine the DMRS information and antenna port information of mapping type B. If the row selected in the antenna port table of mapping type A is a valid row (not a reserved row), and the row selected in the antenna port table of mapping type B is an invalid row (a reserved row), the terminal receives (or sends) a PDSCH (or PUSCH) corresponding to the scheduling information with mapping type A. However, the terminal does not receive (or send) a PDSCH (or PUSCH) corresponding to the scheduling information with mapping type B.

[0443] If the terminal receives a TDRA row with a different mapping type in DCI format, the terminal interprets the value of the antenna port field as one of the valid rows in the antenna port table for that mapping type, according to the defined rules.

[0444] In this case, the valid rows in the antenna port table are those that are not reserved.

[0445] When PDSCH mapping types A and B are set according to Table 41 (for dmrs-Type=1, maxLength=2) and Table 43 (for dmrs-Type=2, maxLength=1), if the antenna port field points to any of rows 0 through 23 when only one codeword is activated, it is a valid value in both antenna port tables. That is, it is not a reserved row in both antenna port tables. However, if the antenna port field points to any of rows 24 through 30, it is a valid value in one antenna port table (dmrs-Type=1, maxLength=2), but not a valid value (reserved) in the other antenna port table (dmrs-Type=2, maxLength=1). Therefore, if TDRA rows of different mapping types are pointed to, the antenna port field will not point to rows 24 through 30.

[0446] To resolve this, we will apply the following method.

[0447] The value specified in the antenna port field is reinterpreted based on the number of valid rows in the antenna port table, and a row is selected from the antenna port table. For example, a row is selected from the antenna port table based on the value obtained by performing a modulo operation on the value specified in the antenna port field using the number of valid rows in the antenna port table.

[0448] For example, if Table 41 (for dmrs-Type=1, maxLength=2) and Table 43 (for dmrs-Type=2, maxLength=1) are set for PDSCH mapping types A and B, let's assume that only one codeword is activated. Let's also assume that the value indicated in the Antenna port field is 25. As mentioned above, row 25 is a value that is not valid (reserved) in the antenna port table (dmrs-Type=2, maxLength=1). To resolve this, the terminal modulo operations 25, the value indicated in the antenna port field, with 24, the number of valid rows in the antenna port table, to obtain 25 mod 24 = 1, and then retrieves the DMRS information and Antenna port information from row 1 of the antenna port table.

[0449] If the value indicated in the antenna port field is valid in one antenna port table but not (reserved) in another antenna port table, the terminal interprets that case as one of the valid values, as follows:

[0450] The terminal interprets the invalid (reserved) value as a specific row in the antenna port table that has a valid value. Here, the specific row is row 0. As another example, the specific row is set by the base station at a higher level.

[0451] The terminal interprets the valid value as the specific row in the antenna port table that has a valid value. Here, the index of the specific row is the value indicated in the antenna port field. For example, row 25 is a non-valid value (reserved) in the antenna port table (dmrs-Type=2, maxLength=1). In this case, row 25 of the antenna port table (dmrs-Type=1, maxLength=2) is used.

[0452] Although the first to sixth embodiments have been described above for the sake of explanation, this is solely for convenience, and each embodiment can be combined and operated in conjunction with others. Furthermore, although the various embodiments of the present invention have been described primarily in terms of terminal operation for the sake of explanation, the technical features of the various embodiments of the present invention described in terms of terminal operation also apply to the base station configuration and base station operation.

[0453] With the multiple push scheduling configuration, the terminal has multiple scheduling entries set in a single TDRA (Time Domain Resource Assignment) row, each of which has an SLIV (Starting and Length Indication Value) and a mapping type. Therefore, the terminal can direct a TDRA row containing scheduling entries with different mapping types through a single DCI.

[0454] Different mapping types are configured with different DMRS configuration information. When the DMRS configuration information is different, the antenna port table for indicating the DMRS port is different. Therefore, the terminal will have different DMRS port(s) configured for different mapping types than PUSCH, due to the different antenna port tables.

[0455] For example, let's assume the following is configured in the DMRS settings for mapping type A.

[0456] DMRS type (dmrs-Type) = 1

[0457] DMRS maximum length (maxLength) = 1

[0458] Furthermore, we assume that the following is configured in the DMRS settings for mapping type B.

[0459] DMRS type (dmrs-Type) = 1

[0460] DMRS maximum length (maxLength) = 2

[0461] Furthermore, we assume that the rank is 2. For reference, rank is information that the terminal can obtain through DCI format. Therefore, the terminal uses one row in Table 23 (the row corresponding to index 0, 1, 2, 3, which is not reserved) when determining the DMRS port to send a PUSCH of mapping type A, and one row in Table 27 (the row corresponding to index 0, 1, ..., 9, which is not reserved) when determining the DMRS port to send a PUSCH of mapping type B. Exemplarily, suppose the base station directs DMRS port {0,1} to send a PUSCH of mapping type A and DMRS port {0,2} to send a PUSCH of mapping type B. In this case, the terminal sees that different DMRS ports are mapped to different mapping types for sending PUSCHs. Therefore, the DMRS port on the terminal that sends a PUSCH of mapping type A and the DMRS port that sends a PUSCH of mapping type B are different from each other.

[0462] The terminal must be specified with the index of the DMRS port for PTRS transmission. The DCI format for scheduling the PUSCH includes a PTRS-DMRS association field to specify the DMRS port for PTRS transmission. As mentioned above, the PTRS-DMRS association field specifies one of the antenna ports among the DMRS ports for the scheduled PUSCH, and when the PUSCH is sent, the PTRS is transmitted on the specified antenna port.

[0463] As mentioned above, the PTRS-DMRS association field is indicated as one of the following, according to Table 49-1: {1st scheduled DMRS port, 2nd scheduled DMRS port, 3rd scheduled DMRS port, 4th scheduled DMRS port}. Let's assume that the current PTRS-DMRS association field indicates the 2nd scheduled DMRS port. In this case, as in the previous example, for mapping type A, the PTRS antenna port is DMRS port 1 to transmit PUSCH on DMRS port {0,1}, and for mapping type B, the PTRS antenna port is DMRS port 2 to transmit PUSCH on DMRS port {0,2}. Therefore, different DMRS ports are used for PTRS transmission for different mapping types.

[0464] To achieve the highest performance, the base station must select the DMRS port with the highest received signal power among the DMRS ports at the PTRS antenna port. This is why the DCI format specifies one DMRS port in the PTRS-DMRS association field. However, for different mapping types, the DMRS port differs depending on the mapping type, so the base station cannot simultaneously specify the DMRS port with the highest received signal power for two different mapping types. For example, in the above example, the terminal transmits PTRS on DMRS port 1 with PUSCH (mapping type A) and PTRS on DMRS port 2 with PUSCH (mapping type B). In this case, assuming the received signal power per DMRS port is DMRS port 1 > DMRS port 0 > DMRS port 2, the base station must specify that PUSCH transmits PTRS on DMRS port 1 with mapping type A and PTRS on DMRS port 0 with PUSCH (mapping type B). However, the DCI format does not support such specification. Hereafter, the present invention discloses a method for determining a PTRS antenna port with a different mapping type.

[0465] This section explains the introduction of the same DMRS port(s) constraint and the same DMRS port(s) instruction constraint.

[0466] The terminal expects mapping type A and mapping type B to use the same antenna port table. To use the same antenna port table, the terminal is configured from the higher layer with the same DMRS type (dmrs-Type) and DMRS maximum length (maxLength). The base station configures the terminal with the same DMRS type (dmrs-Type) and DMRS maximum length (maxLength). The terminal also expects mapping type A and mapping type B to be assigned the same DMRS port(s).

[0467] When a TDRA table is configured containing TDRA rows with different mapping types, the terminal expects mapping type A and mapping type B to use the same antenna port table. That is, when a TDRA table is configured containing TDRA rows with different mapping types, the terminal expects mapping type A and mapping type B to have the same DMRS type (dmrs-Type) and DMRS maximum length (maxLength). The terminal expects the DMRS port(s) for PUSCH, which is the mapping type indicated in the DCI format used to schedule the received PUSCH, to always be the same as the PUSCH DMRS port(s) for mapping type B.

[0468] If a base station configures a terminal with a TDRA table containing TDRA rows of different mapping types, the base station must configure the terminal so that mapping type A and mapping type B use the same antenna port table. In other words, if a base station configures a terminal with a TDRA table containing TDRA rows of different mapping types, the base station must configure the terminal so that the DMRS type (dmrs-Type) and DMRS maximum length (maxLength) are the same for mapping type A and mapping type B.

[0469] If a terminal is configured with a TDRA table that does not contain TDRA rows of different mapping types, then the antenna port tables for mapping type A and mapping type B are either the same or different. In other words, if a terminal is configured with a TDRA table that does not contain TDRA rows of different mapping types, then the DMRS type (dmrs-Type) and DMRS maximum length (maxLength) for mapping type A and mapping type B are either the same or different. To put it another way, if a terminal is configured with a TDRA table that does not contain TDRA rows of different mapping types, then there are no configuration constraints on the DMRS type (dmrs-Type) and DMRS maximum length (maxLength) for mapping type A and mapping type B.

[0470] If a base station configures a terminal's TDRA table that does not contain TDRA rows of different mapping types, the base station configures the terminal to use antenna port tables for mapping type A and mapping type B that are either the same or different. In other words, if a base station configures a terminal's TDRA table that does not contain TDRA rows of different mapping types, the base station configures the terminal to use DMRS types (dmrs-Type) and DMRS maximum length (maxLength) for mapping type A and mapping type B that are either the same or different. To put it another way, if a base station configures a terminal's TDRA table that does not contain TDRA rows of different mapping types, the base station is free to configure the DMRS types (dmrs-Type) and DMRS maximum length (maxLength) for mapping type A and mapping type B without any configuration constraints.

[0471] If the TDRA table configured for a terminal contains at least one TDRA row with a different mapping type, the DMRS type (dmrs-Type) and DMRS maximum length (maxLength) for mapping type A and mapping type B must be the same. This also affects other TDRA rows in the TDRA table.

[0472] For example, suppose the TDRA table contains scheduling information where the first TDRA row is mapping type A, and the second TDRA row contains scheduling information where the second TDRA row is mapping type B. In the existing operation (without the operation of the first embodiment), the base station sets different DMRS types (dmrs-Type) or DMRS maximum lengths (maxLength) for mapping type A and mapping type B at the terminal. Therefore, the PUSCH scheduled in the first TDRA row and the PUSCH scheduled in the second TDRA row could have DMRS with different DMRS types (dmrs-Type) or DMRS maximum lengths (maxLength). However, according to the operation of the first embodiment, the PUSCH scheduled in the first TDRA row and the PUSCH scheduled in the second TDRA row must always have DMRS with the same DMRS type (dmrs-Type) or DMRS maximum length (maxLength). This makes it difficult to configure a DMRS suitable for the base station's mapping type.

[0473] To solve this problem, the following embodiments can be considered.

[0474] The terminal receives additional DMRS settings only for TDRA lines with different mapping types in higher-level signals (e.g., RRC signals). Each DMRS setting includes at least the DMRS type (dmrs-Type) or DMRS maximum length (maxLength). The terminal receives three DMRS settings as follows:

[0475] 1. DMRS Configuration: DMRS configuration for TDRA lines containing only scheduling information of Mapping type A.

[0476] 2nd DMRS Configuration: DMRS configuration for TDRA lines containing only scheduling information, which is Mapping type B.

[0477] Third DMRS configuration: DMRS configuration for TDRA lines including scheduling information of Mapping type A and scheduling information of Mapping type B.

[0478] For reference, the first DMRS setting is a DMRS setting configured with Mapping type A (dmrs-UplinkForPUSCH-MappingTypeA), the second DMRS setting is a DMRS setting configured with Mapping type B (dmrs-UplinkForPUSCH-MappingTypeB), and the third DMRS setting is a newly configured DMRS setting.

[0479] When the terminal receives the DCI format, it performs the following actions:

[0480] The terminal obtains the index of the TDRA row from the TDRA field in the received DCI format. The terminal obtains the scheduling information and the mapping type of the scheduling information contained in the TDRA row.

[0481] If the TDRA row contains only scheduling information where mapping type A, the terminal assumes the first DMRS configuration. Therefore, the terminal determines the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) by the first DMRS configuration and uses the antenna port table based on the DMRS type (dmrs-Type) or DMRS maximum length (maxLength).

[0482] If the TDRA row contains only scheduling information with mapping type B, the terminal assumes a second DMRS configuration. Therefore, the terminal determines the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) by the second DMRS configuration and uses the antenna port table based on the DMRS type (dmrs-Type) or DMRS maximum length (maxLength).

[0483] If a TDRA line contains scheduling information with mapping type A and scheduling information with mapping type B, the terminal assumes a third DMRS configuration. Therefore, the terminal uses an antenna port table determined by the third DMRS configuration, which determines the DMRS type (dmrs-Type) or DMRS maximum length (maxLength). Here, mapping type A and mapping type B scheduled for a TDRA line use the same antenna port table. Thus, the DMRS configurations for mapping type A and mapping type B have the same DMRS port(s), the same number of DMRS symbols, and the same number of CDM groups without data. However, the actual DMRS location to be transmitted is determined differently depending on mapping type A and mapping type B.

[0484] The terminal interprets the `antenna port` field based on the `antenna port` table.

[0485] The terminal obtains DMRS port(s) from the antenna port table according to the value of the antenna port field. DMRS port(s) are the same as PUSCH with mapping type A and PUSCH with mapping type B.

[0486] The terminal receives a DCI-formatted PTRS-DMRS association field that designates one of the DMRS port(s) as the PTRS antenna port. Since the DMRS port for PUSCH (mapping type A) and PUSCH (mapping type B) are the same, the PTRS antenna port is also the same.

[0487] The third DMRS setting is the same as either the first or second DMRS setting. That is, when the third DMRS setting is configured, the terminal will be configured with the same settings as either the first or second DMRS setting, but will not receive settings different from the first and second DMRS settings. Through this limitation, the terminal can be configured with a maximum of two different DMRS settings.

[0488] A new higher-level signal (e.g., RRC signal) is required for the third DMRS configuration. This introduces design and overhead for the higher-level signal. Methods to mitigate this problem are described below.

[0489] The terminal does not have a higher-level signal set for the third DMRS setting. Instead, the third DMRS setting is determined from the following information:

[0490] The terminal always assumes that the third DMRS setting is the same as the first DMRS setting. That is, the terminal uses the DMRS setting for TDRA lines that contains only scheduling information of mapping type A as the third DMRS setting. In other words, the terminal determines the DMRS for PUSCH lines of mapping type B that are scheduled for TDRA lines of different mapping types by using the DMRS setting of mapping type A, i.e., the DMRS type (dmrs-Type) or DMRS maximum length (maxLength). Therefore, the terminal uses the antenna port table of mapping type A for PUSCH lines of mapping type B that are scheduled for TDRA lines of different mapping types. Here, the DMRS position of PUSCH lines of mapping type B follows the same method as mapping type B.

[0491] The terminal always assumes that the third DMRS setting is the same as the second DMRS setting. That is, the terminal uses the DMRS setting for TDRA lines that contains only scheduling information of mapping type B as the third DMRS setting. In other words, the terminal determines the DMRS for mapping type A PUSCHs scheduled to TDRA lines of different mapping types by using the DMRS setting of mapping type B, i.e., the DMRS type (dmrs-Type) or DMRS maximum length (maxLength). Therefore, the terminal uses the antenna port table of mapping type B for mapping type A PUSCHs scheduled to TDRA lines of different mapping types. Here, the DMRS location of the mapping type A PUSCH follows the same method as mapping type A.

[0492] The terminal assumes that the third DMRS setting is the same as either the first or second DMRS setting based on the mapping type of one of the scheduling pieces of scheduling information that is scheduled to TDRA lines with different mapping types.

[0493] For example, the terminal assumes that the third DMRS setting is the same as either the first or second DMRS setting based on the mapping type of the earliest scheduling information among the scheduling information scheduled to TDRA lines of different mapping types. If the mapping type of the earliest scheduling information is mapping type A, the terminal assumes that the DMRS setting for mapping type A, i.e., the first DMRS setting, is the same as the third DMRS setting. If the mapping type of the earliest scheduling information is mapping type B, the terminal assumes that the DMRS setting for mapping type B, i.e., the second DMRS setting, is the same as the third DMRS setting.

[0494] Here, the earliest scheduling information is replaced by the latest scheduling information. Here, the earliest scheduling information is the earliest scheduling information in terms of time.

[0495] In this embodiment, it was assumed that the terminals were set to the same DMRS type (dmrs-Type) or the same DMRS maximum length (maxLength). However, the above conditions are modified and applied as follows.

[0496] The terminal expects the same DMRS type (dmrs-Type) to be set for different mapping types. Here, different DMRS maximum lengths (maxLength) are set for different mapping types. Due to this change in conditions, the terminal uses different DMRS maximum lengths for different mapping types. Therefore, the base station instructs the terminal to use a DMRS length that matches the mapping type. However, in this embodiment, the terminal expects to be instructed to use the same DMRS port(s) for mapping type A and mapping type B.

[0497] The terminal expects the same DMRS maximum length (maxLength) to be set for different mapping types. Here, different DMRS types (dmrs-Type) are set for different mapping types. Due to this change in conditions, the terminal uses different DMRS types (dmrs-Type) for different mapping types. Therefore, the base station sets the DMRS type to match the mapping type for the terminal. However, the terminal expects to receive instructions for the same DMRS port(s) for mapping type A and mapping type B.

[0498] The conditions for the terminal's DMRS type (dmrs-Type) or DMRS maximum length (maxLength) have been explained, but the following conditions are added.

[0499] The terminal expects additional DMRS settings (dmrs-AdditionalPosition) other than the same initial DMRS (first DMRS or front-loaded DMRS) for different mapping types.

[0500] There were constraints on the DMRS settings for mapping type A and mapping type B. For example, mapping type A and mapping type B had to be set to the same DMRS type (dmrs-Type) or the same maximum DMRS length (maxLength). However, without the above constraints, terminals would always expect the same DMRS port(s) to be indicated.

[0501] The terminal expects mapping type A and mapping type B to indicate the same DMRS port(s). Here, the antenna port table for PUSCH with mapping type A and the antenna port table for PUSCH with mapping type B are either the same or different. That is, the DMRS type (dmrs-Type) and DMRS maximum length (maxLength) that the base station sets on the terminal are either the same or different. Therefore, the antenna port table corresponding to mapping type A and the antenna port table corresponding to mapping type B are either the same or different. However, if the received DCI format indicates TDRA lines with different mapping types, the terminal expects the DMRS port(s) for mapping type A and the DMRS port(s) for mapping type B, as determined by the antenna port field in the DCI format, to always be the same.

[0502] The base station can freely configure DMRS settings for mapping type A and mapping type B on the terminal. The DMRS settings include the DMRS type (dmrs-Type) and the maximum DMRS length (maxLength). Here, "freely configure" means that the DMRS settings for mapping type A are independent of the DMRS settings for mapping type B. When the base station instructs the terminal with TDRA lines of different mapping types in DCI format, the base station must specify the value of the antenna port field so that the DMRS port(s) for mapping type A and the DMRS port(s) for mapping type B, as indicated in the antenna port field of the DCI format, are the same.

[0503] Multiple PUSCH scheduling programs introduce the same mapping type constraint.

[0504] If the antenna port table corresponding to mapping type A and the antenna port table corresponding to mapping type B are different for a terminal, the terminal expects the mapping type of the scheduling information contained in the TDRA row to be the same. If the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) for mapping type A and the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) for mapping type B are different for a terminal, the terminal expects the mapping type of the scheduling information contained in the TDRA row to be the same.

[0505] Furthermore, when TDRA rows with different mapping types are set in the TDRA table, the terminal assumes that the antenna port table corresponding to mapping type A and the antenna port table corresponding to mapping type B are the same. When TDRA rows with different mapping types are set in the TDRA table, the terminal assumes that the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) for mapping type A and the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) for mapping type B are the same.

[0506] In other words, the terminal does not expect that the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) of mapping type A and the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) of mapping type B are different from each other, and that TDRA rows of different mapping types will be set in the TDRA table. The terminal does not expect that the antenna port table corresponding to mapping type A and the antenna port table corresponding to mapping type B are different from each other, and that TDRA rows of different mapping types will be set in the TDRA table.

[0507] If a base station configures a terminal to have different DMRS types (dmrs-Type) or DMRS maximum length (maxLength) for mapping type A and different DMRS types (dmrs-Type) or DMRS maximum length (maxLength) for mapping type B, the base station will always configure the mapping type of the scheduling information included in the TDRA line to be the same.

[0508] If a base station sets up TDRA rows with different mapping types in the TDRA table for a terminal, the base station must set the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) for mapping type A to be the same as the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) for mapping type B.

[0509] In other words, the base station sets the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) for mapping type A to be different from the DMRS type (dmrs-Type) or DMRS maximum length (maxLength) for mapping type B, and does not set it so that TDRA rows with different mapping types are included in the TDRA table.

[0510] The terminal determines the location and length of the DMRS based on the DMRS settings in the TDRA field of the received DCI format, because scheduled pushes always have the same mapping type. The terminal also determines one antenna port table based on the DMRS settings in the mapping type. One row in that antenna port table is indicated by the antenna port field.

[0511] The PTRS-DMRS association field indicates two PTRS antenna ports with different mapping types.

[0512] The DCI format used to schedule PUSCH signals received by the terminal includes a DCI field to specify the mapping type for each PTRS antenna port.

[0513] More specifically, some bits in the PTRS-DMRS association field indicate one of the DMRS port(s) of mapping type A as the PTRS antenna port, and the remaining bits in the PTRS-DMRS association field indicate one of the DMRS port(s) of mapping type B as the PTRS antenna port.

[0514] If a terminal is instructed to have TDRA lines with different mapping types, the PTRS-DMRS association field in DCI format consists of 4 bits. Here, the 2 MSB (Most significant bit) bits indicate one of the DMRS port(s) of mapping type A as the PTRS antenna port, and the 2 LSB (Least significant bit) bits indicate one of the DMRS port(s) of mapping type B as the PTRS antenna port.

[0515] When a terminal is assigned a TDRA line, which is a single mapping type, the PTRS-DMRS association field in DCI format consists of 2 bits. These 2 bits designate one of the DMRS port(s) of the mapping type included in the TDRA line as the PTRS antenna port.

[0516] For reference, in the example above, the number of bits required in the PTRS-DMRS association field in DCI format differs when the terminal schedules a PUSCH with a mapping type to a TDRA row in DCI format compared to scheduling a PUSCH with a single mapping type. Therefore, the following actions are taken to match the bits.

[0517] If at least one TDRA row in the TDRA table configured on the terminal contains a different mapping type, the terminal will always expect 4 bits in the PTRS-DMRS association in DCI format. If the terminal is given a TDRA row with a single mapping type, 2 of the 4 bits in the PTRS-DMRS association field in DCI format will indicate one of the DMRS port(s) of the mapping type contained in the TDRA row as the PTRS antenna port. The 2 of the 4 bits are selected as follows:

[0518] The MSB (2 bits) is used to designate one of the DMRS port(s) of a single mapping type included in the TDRA line as the PTRS antenna port. The LSB (2 bits) is not used.

[0519] The LSB 2 bits are used to designate one of the DMRS port(s) of a single mapping type included in the TDRA line as the PTRS antenna port. The MSB 2 bits are not used.

[0520] The system uses either 2 bits of the MSB or 2 bits of the LSB according to the mapping type included in the TDRA line. If the mapping type included in the TDRA line is mapping type A, the system uses 2 bits of the MSB and uses one of the DMRS port(s) of that mapping type as the PTRS antenna port. If the mapping type included in the TDRA line is mapping type B, the system uses 2 bits of the LSB and uses one of the DMRS port(s) of that mapping type as the PTRS antenna port.

[0521] If a terminal is instructed to have TDRA lines with different mapping types, and the DMRS port(s) with different mapping types are different, the PTRS-DMRS association field in DCI format consists of 4 bits. Here, the 2 MSB (Most significant bit) bits indicate one of the DMRS port(s) of mapping type A as the PTRS antenna port, and the 2 LSB (Least significant bit) bits indicate one of the DMRS port(s) of mapping type B as the PTRS antenna port.

[0522] If a terminal is assigned a TDRA line with one mapping type, or if it is assigned TDRA lines with different mapping types but the DMRS port(s) of the different mapping types are the same, the PTRS-DMRS association field in the DCI format consists of 2 bits. These 2 bits designate one of the DMRS port(s) of the mapping type included in the TDRA line as the PTRS antenna port.

[0523] For reference, in the example above, the number of bits required for the PTRS-DMRS association field in DCI format differs when the terminal schedules a PUSCH with different mapping types for the TDRA row in DCI format compared to when it schedules a PUSCH with a single mapping type. Therefore, the following action is taken to match the bits.

[0524] If at least one TDRA row in the TDRA table configured on the terminal contains different mapping types, and the DMRS port(s) for the different mapping types are indicated as different, the terminal will always expect 4 bits in the PTRS-DMRS association field in DCI format. If the terminal is indicated with a TDRA row of one mapping type, or with TDRA rows of different mapping types, but the DMRS port(s) for the different mapping types are the same, then 2 of the 4 bits in the PTRS-DMRS association field in DCI format will indicate one of the DMRS port(s) for the mapping types contained in the TDRA row as the PTRS antenna port. The 2 of the 4 bits are selected using the three methods described above.

[0525] In other words, the conditions for the existence of a 4-bit PTRS-DMRS association field in the DCI format are as follows:

[0526] Condition 1) If at least one row in the TDRA table contains a different mapping type, or

[0527] Condition 2) If at least one row in the TDRA table contains a different mapping type and different DMRS port(s) are directed to different mapping types.

[0528] For reference, if you expect the terminal to always be directed to the same DMRS port(s), the DCI format will have a 4-bit PTRS-DMRS association field when using condition 1, but a 2-bit PTRS-DMRS association field when using condition 2.

[0529] While one PTRS-DMRS association field contains different bits to indicate PTRS antenna ports with different mapping types, a new DCI field is defined. That is, in the above embodiment, the 4-bit PTRS-DMRS association field is represented by a 2-bit first PTRS-DMRS association field and a 2-bit second PTRS-DMRS association field. Preferably, the 2-bit first PTRS-DMRS association field is the MSB 2 bits of the above 4-bit PTRS-DMRS association field, and the 2-bit second PTRS-DMRS association field is the LSB 2 bits of the above 4-bit PTRS-DMRS association field.

[0530] The PTRS-DMRS association field indicates one of the DMRS ports that are scheduled in common for both mapping types.

[0531] The terminal is instructed by the PTRS-DMRS association field to select one of the commonly chosen DMRS port(s) from among DMRS port(s) with different mapping types. Here, the PTRS-DMRS association field is 2 bits.

[0532] Assume the terminal receives {3,4,5} as DMRS port(s) for mapping type A and {2,3,5} as DMRS port(s) for mapping type B. Here, mapping type A is the case where the DMRS type (dmrs-Type) is 2, the maximum DMRS length (maxLength) is 2, the rank is 3, and the Antenna port table indicates a row corresponding to value 2. Mapping type B is the case where the DMRS type (dmrs-Type) is 1, the maximum DMRS length (maxLength) is 2, the rank is 3, and the Antenna port table indicates a row corresponding to value 2.

[0533] The terminal collects the DMRS port(s) that are commonly included among the DMRS port(s) of mapping type A and the DMRS port(s) of mapping type B to generate commonly scheduled DMRS port(s). Specifically, it generates {3,5}, which are the DMRS port(s) that are commonly included among the DMRS port(s) of mapping type A {3,4,5} and the DMRS port(s) of mapping type B {2,3,5}, as commonly scheduled DMRS port(s).

[0534] The terminal receives an indication of one of the commonly scheduled DMRS port(s) in the PTRS-DMRS association field and uses that DMRS port for PTRS transmission. The PTRS-DMRS association field indicates one of the following values: '1st commonly scheduled DMRS port', '2nd commonly scheduled DMRS port', '3rd commonly scheduled DMRS port', and '4th commonly scheduled DMRS port', in ascending order. For example, if the commonly scheduled DMRS port(s) are {3,5} and the PTRS-DMRS association field indicates '1st commonly scheduled DMRS port', the terminal uses DMRS port(s)3 as the antenna port for PTRS transmission. If the PTRS-DMRS association field indicates '2nd commonly scheduled DMRS port', the terminal uses DMRS port(s)5 as the antenna port for PTRS transmission.

[0535] It is assumed that the DMRS port with the highest received signal power is included in both of the two different mapping types. That is, it is not appropriate for a base station to schedule PUSCH with mapping type A and PUSCH with mapping type B to a terminal if the DMRS port with the highest received power is not scheduled to one mapping type and is not scheduled to a different mapping type. Therefore, of the DMRS port(s) that are commonly scheduled in two different mapping types, at least one has the highest received signal power and at least one is used as the antenna port for PTRS transmission.

[0536] However, the above assumption is not always valid. Therefore, the DMRS port with the highest received power belongs to only one mapping type. For this reason, the embodiment is as follows:

[0537] The PTRS-DMRS association field indicates one of the DMRS ports scheduled for the two mapping types.

[0538] The UE receives an indication of one or more DMRS port(s) obtained by collecting all DMRS port(s) of different mapping types from the PTRS-DMRS association field. Here, the PTRS-DMRS association field is greater than 2 bits. Here, the PTRS-DMRS association field is 3 bits.

[0539] For example, assume that the terminal receives {3,4,5} as DMRS port(s) of mapping type A and {2,3,6} as DMRS port(s) of mapping type B. Here, mapping type A is the case where the DMRS type (dmrs-Type) is 2, the maximum DMRS length (maxLength) is 2, the rank is 3, and the Antenna port table indicates a row corresponding to value 2. Mapping type B is the case where the DMRS type (dmrs-Type) is 1, the maximum DMRS length (maxLength) is 2, the rank is 3, and the Antenna port table indicates a row corresponding to value 2.

[0540] The terminal generates all of scheduled DMRS port(s) by collecting both DMRS port(s) of mapping type A and DMRS port(s) of mapping type B. That is, by collecting both DMRS port(s) {3,4,5} of mapping type A and DMRS port(s) {2,3,6} of mapping type B, the total DMRS port(s) {3,4,5,6} is generated as all of scheduled DMRS port(s).

[0541] The terminal receives an instruction in the PTRS-DMRS association field for one of the all of scheduled DMRS port(s), and uses that DMRS port for PTRS transmission. The PTRS-DMRS association field indicates one of the following values: '1st all of scheduled DMRS port', '2nd all of scheduled DMRS port', '3rd all of scheduled DMRS port', '4th all of scheduled DMRS port', '5th all of scheduled DMRS port', '6th all of scheduled DMRS port', '7th all of scheduled DMRS port', or '8th all of scheduled DMRS port', in ascending order. For example, if all of scheduled DMRS port(s) is {3,4,5,6} and the PTRS-DMRS association field indicates '1st all of scheduled DMRS port', the terminal will use DMRS port(s) 3 as the antenna port for PTRS transmission. If the PTRS-DMRS association field indicates '2nd all of scheduled DMRS port', the terminal uses DMRS port(s)4 as the antenna port for PTRS transmission. If the PTRS-DMRS association field indicates '3rd all of scheduled DMRS port', the terminal uses DMRS port(s)5 as the antenna port for PTRS transmission. If the PTRS-DMRS association field indicates '4th all of scheduled DMRS port', the terminal uses DMRS port(s)6 as the antenna port for PTRS transmission.

[0542] The PTRS-DMRS association field directly indicates the index of the DMRS antenna port.

[0543] The terminal receives a designation from the PTRS-DMRS association field for one of the DMRS port(s) scheduled for a different mapping type, and based on that designation, uses one DMRS port for PTRS transmission. In one embodiment, the terminal receives a designation for one of the possible DMRS port(s) regardless of scheduling; that is, the PTRS-DMRS association field indicates the index of one of the designationable DMRS ports.

[0544] Here, the available DMRS ports are all DMRS ports available depending on the DMRS type (dmrs-Type). For example, when the DMRS type (dmrs-type) is set to 1, the available DMRS ports are 0-7. When the DMRS type (dmrs-type) is set to 2, the available DMRS ports are 0-11. When both DMRS type (dmrs-type) are set to 1 and 2 simultaneously for different mapping types, the available DMRS ports are 0-11. The PTRS-DMRS association field indicates one index of the available DMRS ports.

[0545] Here, the available DMRS ports are all DMRS ports that can be used depending on the DMRS type (dmrs-Type) and maximum DMRS length (maxLength). When DMRS type (dmrs-type) is set to 1 and the maximum DMRS length is 1, the available DMRS ports are 0 to 3. When DMRS type (dmrs-type) is set to 1 and the maximum DMRS length is 2, the available DMRS ports are 0 to 7. When DMRS type (dmrs-type) is set to 2 and the maximum DMRS length is 1, the available DMRS ports are 0 to 5. When DMRS type (dmrs-type) is set to 2 and the maximum DMRS length is 2, the available DMRS ports are 0 to 11. If DMRS type (dmrs-type) or maximum DMRS length is set for different mapping types, the maximum DMRS ports for each setting are the available DMRS ports.

[0546] Here, the instructible DMRS ports are a subset of the DMRS port(s) in the DMRS configuration. Some DMRS port(s) are configured via separate higher-level signals.

[0547] The terminal receives an indication of one of the available DMRS port(s) from the PTRS-DMRS association field and uses that DMRS port for PTRS transmission. The PTRS-DMRS association field indicates one of the following values: 'DMRS port 0', 'DMRS port 1', 'DMRS port 2', ..., in ascending order. For example, if the PTRS-DMRS association field indicates 'DMRS port 3', the terminal uses DMRS port(s) 3 as the antenna port for PTRS transmission.

[0548] In this embodiment, the length of the PTRS-DMRS association field is determined by the number of available DMRS port(s). For example, the length of the PTRS-DMRS association field is determined by ceil(log2(number of available DMRS port(s))).

[0549] The PTRS-DMRS association field indicates a PTRS antenna port with a specific mapping type, and all pushers use this PTRS antenna port.

[0550] The terminal receives a directive from the PTRS-DMRS association field to select one of the DMRS port(s) scheduled for a different mapping type, and uses that directive to transmit PTRS. However, in one embodiment, the terminal receives a directive from the PTRS-DMRS association field to select one of the DMRS port(s) scheduled for a particular mapping type, and transmits PTRS on the antenna port determined through the directive. Another mapping type also transmits PTRS on the same antenna port determined through the directive.

[0551] When a terminal receives instructions for a TDRA line with a different mapping type, it selects one of mapping type A and mapping type B to apply the PTRS-DMRS association field. For example, the selection is based on at least one of the following:

[0552] The terminal always selects mapping type A. That is, the PTRS-DMRS association field indicates one of the DMRS port(s) with mapping type A.

[0553] The terminal always selects mapping type B. That is, the PTRS-DMRS association field indicates one of the DMRS port(s) with mapping type B.

[0554] The terminal selects the mapping type of the first scheduled PUSCH. That is, the PTRS-DMRS association field indicates one of the DMRS port(s) of the mapping type of the first scheduled PUSCH. Here, the first scheduled PUSCH is the PUSCH scheduled at the earliest possible time. Here, the first scheduled PUSCH is the PUSCH corresponding to the scheduling information that was first set from the higher hierarchy in the indicated TDRA line.

[0555] Assume the terminal receives {3,4,5} as DMRS port(s) of mapping type A and {2,3,6} as DMRS port(s) of mapping type B. Here, mapping type A is the case where the DMRS type (dmrs-Type) is 2, the maximum DMRS length (maxLength) is 2, the rank is 3, and the row corresponding to value2 is indicated in the Antenna port table. Mapping type B is the case where the DMRS type (dmrs-Type) is 1, the maximum DMRS length (maxLength) is 2, the rank is 3, and the row corresponding to value2 is indicated in the Antenna port table.

[0556] The terminal receives an instruction for one of the DMRS port(s) of the mapping type selected in the PTRS-DMRS association field and uses that DMRS port for PTRS transmission. The PTRS-DMRS association field indicates one of the following values: '1st scheduled DMRS port', '2nd scheduled DMRS port', '3rd scheduled DMRS port', or '4th scheduled DMRS port', in ascending order. For example, if the selected mapping type is mapping type A, the scheduled DMRS port(s) are {3,4,5}, and the PTRS-DMRS association field indicates '1st scheduled DMRS port', the terminal will use DMRS port(s)3 as the antenna port for PTRS transmission. If the PTRS-DMRS association field indicates '2nd scheduled DMRS port', the terminal will use DMRS port(s)4 as the antenna port for PTRS transmission. If the PTRS-DMRS association field indicates '3rd scheduled DMRS port', the terminal uses DMRS port(s) 5 as the antenna port for PTRS transmission.

[0557] If an antenna port is included in all scheduled DMRS port(s) of two different mapping types, PTRS is transmitted via the antenna port. However, a determined antenna port may be included in the scheduled DMRS port(s) of one mapping type, but not in the scheduled DMRS port(s) of the other mapping type. In this case, the terminal behaves as follows:

[0558] As a first step, if the determined anetnna port is not included in the scheduled DMRS port(s) of the other mapping type, no PTRS is sent to the PUSCH of that mapping type. In other words, PTRS is sent only if there is one mapping type.

[0559] As a second action, if the determined anetnna port is not included in the scheduled DMRS port(s) of another mapping type, a PTRS is sent to the PUSCH of the mapping type on a specific DMRS port, where the specific DMRS port is the DMRS port with the lowest index among the scheduled DMRS ports.

[0560] Although the embodiments have been described separately above, this is for the sake of clarity, and the embodiments can also be combined and implemented. Furthermore, in the various embodiments of the present invention, the operation of the terminal has been described primarily for the sake of clarity, but the technical features of the various embodiments of the present invention described in terms of terminal operation also apply to the configuration and operation of the base station.

[0561] Although the specific embodiments for interpreting antenna port-related fields and the specific embodiments for interpreting PTRS-related fields were described separately above, this is solely for the sake of explanation, and it is also possible to combine and implement the embodiments for interpreting antenna port-related fields and PTRS-related fields. Furthermore, the term "embodiment" is also used for the sake of explanation, and it should be noted that embodiments can be selectively combined and implemented within a non-contradictory range.

[0562] Figure 14 shows the structure of a terminal in a wireless communication system according to one embodiment.

[0563] Referring to Figure 14, the terminal includes a transceiver (referred to as a terminal receiver 1400 and a terminal transmitter 1410), memory (not shown), and a terminal processing unit 1405 (or a terminal control unit or processor). The terminal's transceiver (1400, 1410), memory, and terminal processing unit 1405 operate according to the terminal communication method described above. However, the components of the terminal are not limited to the example above. For example, the terminal may include more or fewer components than those described above. Moreover, the transceiver, memory, and processor may be implemented in the form of a single chip.

[0564] The transmitting and receiving unit transmits and receives signals with the base station. Here, the signal includes control information and data. For this purpose, the transmitting and receiving unit consists of an RF transmitter that converts and amplifies the frequency of the transmitted signal, and an RF receiver that low-noise amplified the received signal and converts its frequency down. However, this is only one embodiment of the transmitting and receiving unit, and the components of the transmitting and receiving unit are not limited to an RF transmitter and an RF receiver.

[0565] Furthermore, the transmitting and receiving unit receives signals via the wireless channel and outputs them to the processor, and transmits the signals output from the processor via the wireless channel.

[0566] Memory stores programs and data necessary for the operation of the terminal. It also stores control information or data contained in signals transmitted and received by the terminal. Memory consists of storage media such as ROM (Read-On-Demand), RAM (Remote-Input / RAM), hard disks, CD-ROMs, DVDs, or combinations of storage media. Multiple memory modules may also be present.

[0567] Furthermore, the processor controls a series of processes to enable the terminal to operate according to the above-described embodiment. For example, the processor controls the terminal's components to receive a DCI consisting of two layers and to receive multiple PDSCHs simultaneously. There may be multiple processors, and the processors control the terminal's components by executing programs stored in memory.

[0568] Figure 15 shows the structure of a base station in a wireless communication system according to one embodiment.

[0569] Referring to Figure 15, the base station includes a transceiver unit, referred to as a base station receiver 1500 and a base station transmitter 1510, a memory (not shown), and a base station processing unit 1505 (or a base station control unit or processor). The base station's transceiver unit (1500, 1510), memory, and base station processing unit 1505 operate according to the base station communication method described above. However, the components of the base station are not limited to the example above. For example, the base station may include more or fewer components than those described above. Moreover, the transceiver unit, memory, and processor may be implemented in the form of a single chip.

[0570] The transmitting and receiving unit transmits and receives signals to and from the terminal. Here, the signal includes control information and data. For this purpose, the transmitting and receiving unit consists of an RF transmitter that converts and amplifies the frequency of the transmitted signal, and an RF receiver that low-noise amplified the received signal and converts its frequency down. However, this is only one embodiment of the transmitting and receiving unit, and the components of the transmitting and receiving unit are not limited to an RF transmitter and an RF receiver.

[0571] Furthermore, the transmitting and receiving unit receives signals via the wireless channel and outputs them to the processor, and transmits the signals output from the processor via the wireless channel.

[0572] Memory stores the programs and data necessary for the operation of the base station. It also stores control information or data contained in the signals transmitted and received by the base station. Memory consists of storage media such as ROM (Read-On-Demand), RAM (Remote-Input / RAM), hard disks, CD-ROMs, DVDs, or combinations of storage media. Multiple memory units may also be present.

[0573] The processor controls a series of processes to enable the base station to operate according to the embodiments of the present invention described above. For example, the processor configures a two-tiered DCI containing allocation information for a number of PDSCHs and controls each component of the base station to transmit it. There may be multiple processors, and the processors perform the base station component control operations by executing programs stored in memory.

[0574] The methods according to the embodiments described in the claims or specification of the present invention are implemented in the form of hardware, software, or a combination of hardware and software.

[0575] When implemented in software, a computer-readable recording medium is provided that stores one or more programs (software modules). The one or more programs stored on the computer-readable recording medium are configured for execution by one or more processors in an electronic device. The one or more programs include instructions that cause the electronic device to perform the methods according to the embodiments described in the claims or specification of the present invention.

[0576] Such programs (software modules, software) are stored in random access memory, non-volatile memory including flash memory, ROM (Read Only Memory), electrically erasable programmable ROM (EEPROM), magnetic disc storage device, Compact Disc-ROM (Read Only Memory), Digital Versatile Discs (DVDs), or other forms of optical storage, magnetic cassettes, or in memory composed of some or all of these. Furthermore, each constituent memory can contain multiple instances.

[0577] Furthermore, the program is stored in an attachable storage device that is accessed via a communication network such as the Internet, Intranet, LAN (Local Area Network), WLAN (Wide LAN), or SAN (Storage Area Network), or a combination thereof. Such a storage device is connected to an apparatus that implements embodiments of the present invention via an external port. In addition, a separate storage device on the communication network may be connected to an apparatus that implements embodiments of the present invention.

[0578] In the specific embodiments of the present invention described above, the components included in the present invention are expressed singly or plurally by the specific embodiments. However, the singly or plural expressions are selected to suit the circumstances presented for the convenience of explanation, and the present invention is not limited to singly or plural components. Even if a component is expressed plurally, it may consist of a singular component, or even if a component is expressed singly, it may consist of a plural component.

[0579] On the other hand, the embodiments of the present invention disclosed in this specification and drawings are merely examples provided to facilitate the explanation of the present invention and aid in its understanding, and are not intended to limit the scope of the present invention. That is, it is obvious to a person with ordinary skill in the art to which the present invention belongs that other modifications based on the technical idea of ​​the present invention are possible. Furthermore, each embodiment can be combined with one another as needed. For example, parts of one embodiment different from one embodiment of the present invention may be combined with each other to operate a base station and a terminal. For example, parts of the first and second embodiments of the present invention may be combined with each other to operate a base station and a terminal. In addition, although the embodiments of the present invention have been presented based on an FDD LTE system, other modifications based on the technical idea of ​​these embodiments may be possible for other systems such as TDD LTE systems, 5G, or NR systems.

[0580] On the other hand, in the drawings illustrating the method of the present invention, the explanatory steps do not necessarily correspond to the execution steps, and the order may be changed or they may be performed in parallel.

[0581] Alternatively, drawings illustrating the method of the present invention may omit some components and include only some components, to the extent that they do not impair the essence of the present invention.

[0582] Furthermore, the methods of the present invention can be implemented by combining some or all of the contents included in each embodiment, to the extent that they do not impair the essence of the present invention.

[0583] Although various embodiments of the present invention have been described above, the above description in this specification is illustrative, and the embodiments of the present invention are not limited to those disclosed. A person with ordinary skill in the art to which the present invention pertains will understand that the invention can be readily modified into other specific forms without altering the technical idea or essential features of the invention. The scope of the present invention is indicated by the claims set forth below rather than by the detailed description, and all modifications or altered forms derived from the meaning and scope of the claims and the concept of equivalents thereto should be interpreted as being included within the scope of the present invention. [Explanation of symbols]

[0584] 101 Resource Element (RE) 102, 501 Orthogonal Frequency Division Multiplexing (OFDM) symbols 103 Subcarrier 104 Resource Block (RB) 110, 201 Subframes 200 Frames 202, 203, 420 Slots 300 Terminal Bandwidth (UE Bandwidth) 301 Bandwidth portion #1 (BWP#1) 302 Bandwidth portion #2 (BWP#2) 401 Control Area #1 402 Control Area #2 403 Frequency Resources 404 Control Resource Set Duration 410 Terminal bandwidth portion (UE bandwidth part) 502 Physical Resource Block (PRB) 503 Resource Element Group (REG) 504 Control Channel Element (CCE) 505 Demodulation Reference Signal (DMRS) 601 Downlink Data Channel 602 Rate Matching Resources 603 Time Domain Resource Allocation Information 604 Frequency Domain Resource Allocation Information 605 Periodicity information 1100, 1110, 1120 Physical Downlink Control Channel (PDCCH) 1101, 1102, 1103, 1104, 1111, 1112, 1121, 1301, 1302, 1303, 1304 Physical Downlink Shared Channel (PDSCH) 1200 Time Domain Resource Assignment (TDRA) field 1205, 1255 Modulation Coding Scheme (MCS) Field 1210, 1260, 1261 New Data Indicator (NDI) fields 1215, 1262, 1263 Redundancy Version (RV) fields 1220, 1270 Hybrid Automatic Repeat Request (HARQ) fields 1225, 1275 Antenna port(s) fields 1230, 1280 DMRS sequence initialization fields 1235 padding bits 1305 Physical Uplink Control Channel (PUCCH) 1400 Terminal receiver 1405 Terminal Processing Unit 1410 Terminal Transmitter 1500 Base station receiving unit 1505 Base Station Processing Unit 1510 Base station transmitter

Claims

[Claim 1] A method performed by a terminal in a wireless communication system, The process involves receiving time-domain resource allocation (TDRA) information from the base station, The steps include receiving downlink control information (DCI) from the base station, which includes a TDRA field and an antenna port field for scheduling multiple physical downlink shared channels (PDSCH), When the first method is used for the antenna port field, the steps include applying the value of the antenna port field to each of the multiple physical downlink shared channels, A method characterized by, when a second method is used for the antenna port field, comprising the steps of applying a first bit field of the antenna port field to a first physical downlink shared channel and applying a second bit field of the antenna port field to a second physical downlink shared channel.

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