Method for transmitting uplink channel in wireless communication system and apparatus therefor

Abstract

A method is provided for performing uplink channel transmission in a wireless communication system, the method being performed by a terminal and comprising the steps of: receiving a system information block 1 (SIB1) from a base station; sending a preamble for a random access procedure to the base station; receiving a random access response (RAR) to the preamble from the base station; and sending a PUSCH to the base station based on the random access response.

Description

Technical Field

[0001] This specification relates to a wireless communication system, and more specifically, to a method and apparatus for transmitting an uplink channel. Background Technology

[0002] Following the commercialization of fourth-generation (4G) communication systems, efforts are underway to develop new fifth-generation (5G) communication systems to meet the increasing demand for wireless data services. 5G communication systems are also referred to as post-4G network communication systems, post-LTE systems, or new radio (NR) systems. To achieve high data transmission rates, 5G communication systems include systems operating in 6 GHz or higher millimeter-wave (mmWave) frequency bands, and systems operating in 6 GHz or lower frequency bands are also being considered to ensure coverage. The implementation methods in base stations and terminals are being considered.

[0003] The 3GPP (3rd Generation Partnership Project) NR system improves network spectral efficiency and enables communication providers to offer more data and voice services on a given bandwidth. Therefore, the 3GPP NR system is designed to meet the demand for high-speed data and media transmission in addition to supporting a large volume of voice traffic. The advantages of the NR system include higher throughput and lower latency on the same platform, support for Frequency Division Duplex (FDD) and Time Division Duplex (TDD), and lower operating costs due to the enhanced end-user environment and simpler architecture. For more efficient data processing, the NR system's dynamic TDD can use methods to change the number of Orthogonal Frequency Division Multiplexing (OFDM) symbols that can be used in the uplink and downlink based on the data traffic direction of the cell's users. For example, when downlink traffic in a cell is greater than uplink traffic, the base station can allocate multiple downlink OFDM symbols to a time slot (or subframe). Information regarding the time slot configuration should be sent to the terminal.

[0004] To mitigate path loss and increase transmission distance in the mmWave band, beamforming, massive MIMO, full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, hybrid beamforming combining analog and digital beamforming, and massive MIMO technologies are discussed in 5G communication systems. Furthermore, for network improvements, technologies related to evolved small cells, advanced small cells, cloud radio access networks (cloud RAN), ultra-dense networks, device-to-device (D2D) communication, vehicle-to-everything (V2X) communication, wireless backhaul, non-terrestrial network communication (NTN), mobile networks, cooperative communication, coordinated multipoint (CoMP), and interference cancellation are being developed in 5G communication systems. Additionally, hybrid FSK and QAM modulation (FQAM) and sliding window superposition coding (SWSC) are being developed as advanced coding and modulation (ACM) schemes, while filter bank multicarrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) are being developed as advanced connectivity technologies in 5G systems.

[0005] Simultaneously, within the human-centric network of interconnected networks where humans generate and consume information, the Internet has evolved into the Internet of Things (IoT) network, which exchanges information between distributed components such as objects. The Internet of Everything (IoE) technology, combining IoT with big data processing through connections to cloud servers, is also emerging. Realizing IoT requires technological elements such as sensing technology, wired / wireless communication and network infrastructure, service interface technology, and security technology. This has led to the recent research into technologies such as sensor networks, machine-to-machine (M2M), and machine-type communication (MTC) to connect objects. In the IoT environment, intelligent Internet of Things (IT) services can be provided, collecting and analyzing data generated from connected objects to create new value in human life. Through the integration and hybridization of existing information technology (IT) with various industries, IoT can be applied to areas such as smart homes, smart buildings, smart cities, smart cars or connected cars, smart grids, healthcare, smart appliances, and advanced medical services.

[0006] Therefore, various attempts have been made to apply 5G communication systems to IoT networks. For example, technologies such as sensor networks, machine-to-machine (M2M), and machine-type communication (MTC) are implemented using techniques such as beamforming, MIMO, and array antennas. The application of cloud RAN as a big data processing technology is an example of the convergence of 5G and IoT technologies. Typically, mobile communication systems are developed to provide voice services while ensuring user activity.

[0007] However, mobile communication systems are not only expanding their voice services but also their data services, and have now evolved to the point of providing high-speed data services. However, due to resource shortages and users' demands for high-speed services, more advanced mobile communication systems are needed within the current mobile communication systems providing services. Summary of the Invention

[0008] Technical issues

[0009] One aspect of this specification is to provide a method and apparatus for transmitting an uplink channel in a wireless communication system.

[0010] Technical solutions

[0011] This specification provides a method and apparatus for transmitting an uplink channel in a wireless communication system.

[0012] Specifically, a method for transmitting an uplink channel in a wireless communication system includes: a terminal receiving a System Information Block 1 (SIB1) from a base station; transmitting a preamble for a random access procedure to the base station; receiving a Random Access Response (RAR) for the preamble from the base station, the random access response including information scheduling a Physical Uplink Shared Channel (PUSCH) to be transmitted by the terminal to the base station; and transmitting the PUSCH to the base station based on the random access response, wherein the SIB1 includes information about a candidate set of repeated transmission counts, the candidate set of repeated transmission counts including values ​​of one or more repeated transmission counts for repeated transmissions of the PUSCH, the random access response including information indicating one of the values ​​of the one or more repeated transmission counts included in the candidate set of repeated transmission counts, and the number of times the transmission of the PUSCH is repeated as many times as the one value.

[0013] The method further includes: receiving downlink control information (DCI) from the base station by the terminal, including information for scheduling retransmission PUSCH; and repeatedly sending the retransmission PUSCH to the base station based on the DCI, wherein the information for scheduling the retransmission PUSCH includes information on the repetition count of the retransmission PUSCH, the information on the repetition count of the retransmission PUSCH being included in the HARQ process number field of the DCI, the retransmission PUSCH being the same as the PUSCH; and sending the DCI by the base station when the base station fails to receive the PUSCH sent by the terminal.

[0014] In a wireless communication system, a terminal for transmitting an uplink channel includes: a transceiver; and a processor configured to control the transceiver, wherein the processor is configured to receive System Information Block 1 (SIB1) from a base station; transmit a preamble for a random access procedure to the base station; receive a Random Access Response (RAR) from the base station for the preamble, the random access response including information scheduling a Physical Uplink Shared Channel (PUSCH) to be transmitted by the terminal to the base station; and transmit the PUSCH to the base station based on the random access response, wherein the SIB1 includes information about a candidate set of repeated transmission counts, the candidate set of repeated transmission counts including values ​​of one or more repeated transmission counts for repeated transmissions of the PUSCH, the random access response including information indicating one of the values ​​of the one or more repeated transmission counts included in the candidate set of repeated transmission counts, and that the transmission of the PUSCH is repeated as many times as the one value.

[0015] The processor is configured to receive downlink control information (DCI) from the base station, including information for scheduling retransmission PUSCH, and to repeatedly send the retransmission PUSCH to the base station based on the DCI, wherein the information for scheduling the retransmission PUSCH includes information on the repetition count of the retransmission PUSCH, the repetition count of the retransmission PUSCH being included in the HARQ process number field of the DCI, the retransmission PUSCH being the same as the PUSCH, and the base station sending the DCI when the base station fails to receive the PUSCH sent by the terminal.

[0016] The random access response corresponds to a Physical Downlink Shared Channel (PDSCH) that includes uplink (UL) clearance.

[0017] Information indicating the value is included in at least one of the Time Domain Resource Assignment (TDRA), Modulation and Coding Scheme (MCS), and Transmission Power Control (TPC) fields of the random access response.

[0018] When information indicating a value is included in the MCS field, the value is indicated by one or more most significant bits (MSBs) of the bits in the MCS field.

[0019] When information indicating a value is included in the TPC field, the value is indicated by one or more least significant bits (LSBs) of the bits in the TPC field.

[0020] The SIB1 includes at least one of information related to the preamble and the RACH timing, and transmits the PUSCH in resources determined based on at least one of the information related to the preamble and the RACH timing.

[0021] The DCI is scrambled by TC-RNTI, and the format of the DCI is DCI format 0_0.

[0022] Each of the values ​​in the one or more repeat transmission counts is a power of 2.

[0023] The values ​​of the one or more repeat transmission counts are 1, 2, 4 and 8, respectively.

[0024] The random access response includes a frequency hopping flag indicating whether the PUSCH performs frequency hopping, and the PUSCH performing intra-slot frequency hopping or inter-slot frequency hopping based on the value and the frequency hopping flag.

[0025] When one of the values ​​is 1, the PUSCH performs in-slot frequency hopping when the value of the frequency hopping flag indicates that the PUSCH should perform frequency hopping, and the PUSCH does not perform frequency hopping when the value of the frequency hopping flag indicates that the PUSCH should not perform frequency hopping.

[0026] When one of the values ​​is greater than 1, the PUSCH performs inter-slot frequency hopping when the value of the frequency hopping flag indicates that the PUSCH should perform frequency hopping, and the PUSCH does not perform frequency hopping when the value of the frequency hopping flag indicates that the PUSCH should not perform frequency hopping.

[0027] The random access response further includes information about the resources in which the first repeated transmission of the PUSCH is performed. This information is a time slot offset between the resources in which the random access response is received and the resources in which the first repeated transmission of the PUSCH is performed. The SIB1 further includes information related to a Time Division Duplex (TDD) configuration. This TDD configuration information is about the type of symbols configured for the time slots. The type of symbol is one of the following: a downlink symbol configured for downlink transmission, an uplink symbol configured for uplink transmission, and a flexible symbol not determined to be either the downlink or uplink symbol. The PUSCH is repeated in time slots, and the resources in which the first repeated transmission of the PUSCH is performed are resources spaced from the resources in which the random access response is received by an amount equal to the time slot offset.

[0028] The resource in which the first repeated transmission of the PUSCH is performed is a flexible time slot, which is a repeated transmission after the first repeated transmission of the PUSCH is performed on the uplink time slot, the flexible time slot is configured by including at least one flexible symbol, and the entire uplink time slot is configured by the uplink symbol.

[0029] A method for receiving an uplink channel in a wireless communication system is performed by a base station and includes: sending a System Information Block 1 (SIB1) to a terminal; receiving a preamble for a random access procedure from the terminal; sending a Random Access Response (RAR) to the terminal for the preamble, the random access response including information scheduling a Physical Uplink Shared Channel (PUSCH) to be transmitted by the terminal to the base station; and receiving the PUSCH based on the random access response from the terminal, wherein the SIB1 includes information about a candidate set of repeated transmission counts, the candidate set of repeated transmission counts including values ​​of one or more repeated transmission counts for repeated transmissions of the PUSCH, the random access response including information indicating a value of one of the values ​​of the one or more repeated transmission counts included in the candidate set of repeated transmission counts, and the number of times the transmission of the PUSCH is repeated as many times as the one value.

[0030] Function of the present invention

[0031] This specification provides a method for repeatedly transmitting Msg3PUSCH during a random access procedure.

[0032] This specification provides a method for inter-slot frequency hopping for repeatedly transmitted Msg3 PUSCH.

[0033] This specification provides a method for determining resources that repeatedly send Msg3 PUSCH.

[0034] The effects that can be obtained through this specification are not limited to those described above, and other effects not mentioned will be clearly understood by those skilled in the art to which this disclosure pertains, based on the following description. Attached Figure Description

[0035] Figure 1 This diagram illustrates an example of a wireless frame structure used in a wireless communication system.

[0036] Figure 2 This diagram illustrates an example of a downlink (DL) / uplink (UL) timeslot structure in a wireless communication system.

[0037] Figure 3 This is a diagram used to illustrate the physical channels used in 3GPP systems and typical signal transmission methods using those physical channels.

[0038] Figure 4a and Figure 4b The diagram illustrates the SS / PBCH block used for initial cell access in a 3GPP NR system.

[0039] Figure 5a and Figure 5b The diagram illustrates the process of transmitting control information and control channels in a 3GPP NR system.

[0040] Figure 6 The diagram shows a control resource set (CORESET) in a 3GPP NR system that can transmit the Physical Downlink Control Channel (PDCCH).

[0041] Figure 7 The diagram illustrates a method for configuring the PDCCH search space in a 3GPP NR system.

[0042] Figure 8 This is a conceptual diagram illustrating carrier aggregation.

[0043] Figure 9 This is a diagram used to illustrate single-carrier communication and multi-carrier communication.

[0044] Figure 10 This is a diagram illustrating an example of the application of cross-carrier scheduling technology.

[0045] Figure 11 This is a block diagram illustrating the configuration of a UE and a base station according to an embodiment of the present disclosure.

[0046] Figure 12 The illustration shows a method for scheduling a physical uplink shared channel in the time domain according to an embodiment of the present disclosure.

[0047] Figure 13 The illustration shows a method for scheduling a physical uplink shared channel in the frequency domain according to an embodiment of the present disclosure.

[0048] Figure 14 The illustration shows repeated transmission of a physical uplink shared channel according to an embodiment of the present disclosure.

[0049] Figure 15 The figure illustrates a method for scheduling the physical uplink control channel according to an embodiment of the present disclosure.

[0050] Figure 16 The illustration shows repeated transmission of the physical uplink control channel according to an embodiment of the present disclosure.

[0051] Figure 17 This is a diagram illustrating the repeated transmission of Msg3 PUSCH according to an embodiment of the present disclosure.

[0052] Figure 18 This is a diagram illustrating repeated transmissions of Msg3PUSCH using three DMRS according to an embodiment of this disclosure.

[0053] Figures 19 to 21 The illustration shows a Msg3 PUSCH transmission method using two DMRSs according to an embodiment of the present disclosure.

[0054] Figures 22 to 26 The illustration shows a method for determining the number of modulation symbols used for multiplexing uplink control information included in Msg3 PUSCH, according to an embodiment of the present disclosure.

[0055] Figure 27 and Figure 28 The illustration shows resources available for repeated transmission of Msg3 PUSCH according to an embodiment of the present disclosure.

[0056] Figure 29 The illustration shows a method for determining a frequency hopping method based on the repetition count of PUCCH according to an embodiment of the present disclosure.

[0057] Figure 30 This is a flowchart illustrating a method for a terminal to send Msg3 PUSCH according to an embodiment of the present disclosure. Detailed Implementation

[0058] The terminology used in this specification adopts, as far as possible, commonly used terms that are widely used in light of the functions of this invention; however, these terms may be modified according to the intent, practice, and emergence of new technologies of those skilled in the art. Furthermore, in certain cases, there are terms arbitrarily chosen by the applicant, and in such cases, their meaning will be described in the corresponding descriptive section of this invention. Therefore, it is intended to reveal that the terminology used in this specification should not be analyzed solely based on its name, but rather on its substantive meaning within the entire specification.

[0059] Throughout the specification and subsequent claims, when an element is described as being “connected” to another element, that element may be “directly connected” to the other element or “electrically connected” to the other element via a third element. Furthermore, unless explicitly stated otherwise, the word “comprising” will be understood to imply the inclusion of the stated element without implying the exclusion of any other elements. Additionally, in some exemplary embodiments, limitations such as “greater than or equal to” or “less than or equal to” based on a specific threshold may be appropriately replaced with “greater than” or “less than”, respectively.

[0060] The following technologies can be used in various wireless access systems: such as Code Division Multiple Access (CDMA), Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), Orthogonal Frequency Division Multiple Access (OFDMA), and Single Carrier-FDMA (SC-FDMA). CDMA can be implemented using wireless technologies such as Universal Terrestrial Radio Access (UTRA) or CDMA2000. TDMA can be implemented using wireless technologies such as Global System for Mobile Communications (GSM), General Packet Radio Service (GPRS), and Enhanced Data Rate GSM Evolution (EDGE). OFDMA can be implemented using wireless technologies such as IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, and Evolved UTRA (E-UTRA). UTRA is part of the Universal Mobile Telecommunications System (UMTS). The 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) is part of Evolved UMTS (E-UMTS) using Evolved UMTS Terrestrial Radio Access (E-UTRA), and LTE Advanced (A) is an evolved version of 3GPP LTE. 3GPP New Radio (NR) is a system designed separately from LTE / LTE-A and is intended to support Enhanced Mobile Broadband (eMBB), Ultra-Reliable Low Latency Communication (URLLC), and Massive Machine-Type Communication (mMTC) services as required by IMT-2020. For clarity, 3GPP NR is described primarily, but the technical concept of this invention is not limited thereto.

[0061] Unless otherwise specified in this specification, a base station may refer to a next-generation node B (gNB) as defined in 3GPP NR. Furthermore, unless otherwise stated, a terminal may refer to a user equipment (UE). In the following, for the purpose of facilitating understanding of the description, each element is separately divided into embodiments and described, but each of the embodiments may be used in conjunction with each other. In this disclosure, the configuration of the UE may be instructive of the configuration by the base station. Specifically, the base station may transmit channels or signals to the UE to configure parameter values ​​used in the UE's operation or wireless communication system.

[0062] Figure 1 This diagram illustrates an example of a wireless frame structure used in a wireless communication system.

[0063] refer to Figure 1 The radio frames (or radio frames) used in 3GPP NR systems can have a duration of 10ms (Δf). max N f / 100)*T c The length of the radio frame is Δf. Furthermore, a radio frame consists of 10 equal-sized subframes (SF). Here, Δf... max =480*103 Hz, N f =4096, T c =1 / (Δf) ref *N f,ref ), Δf ref =15*10 3 Hz, and N f,ref =2048. Numbers from 0 to 9 can be assigned to 10 subframes within a single radio frame. Each subframe is 1ms long and can include one or more time slots depending on the subcarrier spacing. More specifically, in 3GPP NR systems, the usable subcarrier spacing is 15*2. μ The subcarrier spacing can be configured as μ = 0, 1, 2, 3, or 4. That is, 15 kHz, 30 kHz, 60 kHz, 120 kHz, and 240 kHz can be used for subcarrier spacing. A subframe of 1 ms length can include 2... μ There are 2 time slots. In this case, the length of each time slot is 2. -μ ms. This can range from 0 to 2. μ The number -1 is assigned to 2 within a subframe. μ Each time slot. Furthermore, slots from 0 to 10*2 can be allocated. μ The number -1 is assigned to a time slot within a radio frame. Time resources can be distinguished by at least one of the radio frame number (also known as the radio frame index), subframe number (also known as the subframe index), and time slot number (or time slot index).

[0064] Figure 2 This diagram illustrates an example of a downlink (DL) / uplink (UL) timeslot structure in a wireless communication system. Specifically, Figure 2 The structure of the resource grid of the 3GPP NR system is shown.

[0065] Each online port has a resource grid. (See reference) Figure 2 A time slot comprises multiple Orthogonal Frequency Division Multiplexing (OFDM) symbols in the time domain and multiple Resource Blocks (RBs) in the frequency domain. An OFDM symbol also refers to a symbol interval. Unless otherwise specified, an OFDM symbol may be simply referred to as a symbol. An RB comprises 12 consecutive subcarriers in the frequency domain. (See reference...) Figure 2 The signal transmitted from each time slot can be composed of N size,μ grid,x *N RB sc Subcarriers and N slot symb The resource grid of OFDM symbols is used for representation. Here, x = DL when the signal is a DL signal, and x = UL when the signal is a UL signal. Nsize,μ grid,x This represents the number of resource blocks (RBs) based on the subcarrier spacing component μ (x is DL or UL), and N slot symb Indicates the number of OFDM symbols in the time slot. N RB sc It is the number of subcarriers that make up an RB and N RB sc =12. OFDM symbols can be referred to as cyclic shift OFDM (CP-OFDM) symbols or discrete Fourier transform extended OFDM (DFT-s-OFDM) symbols according to the multiple access scheme.

[0066] The number of OFDM symbols included in a time slot can vary depending on the length of the cyclic prefix (CP). For example, with normal CP, a time slot includes 14 OFDM symbols, but with extended CP, a time slot can include 12 OFDM symbols. In certain embodiments, extended CP can only be used with a 60 kHz subcarrier spacing. Figure 2 For ease of description, as an example, a time slot is configured with 14 OFDM symbols; however, embodiments of this disclosure can be applied in a similar manner to time slots with different numbers of OFDM symbols. References Figure 2 Each OFDM symbol includes N in the frequency domain. size,μ grid,x *N RB sc Subcarriers can be categorized into data subcarriers for data transmission, reference signal subcarriers for reference signal transmission, and guard bands. The carrier frequency is also known as the center frequency (fc).

[0067] An RB can be composed of N in the frequency domain RB sc (For example, 12) consecutive subcarriers are defined. For reference, a resource configured with one OFDM symbol and one subcarrier can be called a resource element (RE) or tone. Therefore, an RB can be configured with N slot symb *N RB sc Each resource element in the resource grid can be uniquely defined by a pair of indices (k, l) in a time slot. k can be from 0 to N in the frequency domain. size,μ grid,x *N RB sc -1 is the index assigned, and l can be from 0 to N in the time domain. slot symb -1 is the index assigned.

[0068] To enable the UE to receive or transmit signals from the base station, the UE's time / frequency can be synchronized with the base station's time / frequency. This is because when the base station and the UE are synchronized, the UE can determine the necessary time and frequency parameters to demodulate the DL signal and transmit the UL signal at the correct time.

[0069] Each symbol of a radio frame used in Time Division Duplex (TDD) or unpaired spectrum can be configured with at least one of DL symbol, UL symbol, and flexible symbol. Radio frames used as DL carriers in Frequency Division Duplex (FDD) or paired spectrum can be configured with either DL symbol or flexible symbol, while radio frames used as UL carriers can be configured with either UL symbol or flexible symbol. In a DL symbol, DL transmission is possible, but UL transmission is not. In a UL symbol, UL transmission is possible, but DL transmission is not. A flexible symbol can be determined as being used as either DL or UL based on the signal.

[0070] Information regarding the type of each symbol—that is, information indicating any of DL symbols, UL symbols, and flexible symbols—can be configured using cell-specific or public Radio Resource Control (RRC) signals. Furthermore, information regarding the type of each symbol can be additionally configured using UE-specific or dedicated RRC signals. The base station uses cell-specific RRC signals to inform i) the period of the cell-specific time slot configuration, ii) the number of time slots containing only DL symbols from the beginning of the cell-specific time slot configuration period, iii) the number of DL symbols starting from the first symbol of the time slot immediately following a time slot containing only DL symbols, iv) the number of time slots containing only UL symbols from the end of the cell-specific time slot configuration period, and v) the number of UL symbols starting from the last symbol of the time slot immediately preceding a time slot containing only UL symbols. Here, a symbol not configured with either UL or DL ​​symbols is a flexible symbol.

[0071] When information about symbol type is configured using UE-specific RRC signals, the base station can use cell-specific RRC signals to signal whether a flexible symbol is a DL symbol or a UL symbol. In this case, the UE-specific RRC signals cannot change a DL symbol or UL symbol configured using cell-specific RRC signals to another symbol type. The UE-specific RRC signals can signal the corresponding N of each time slot. slot symb The number of DL symbols in each symbol and the corresponding time slot N slot symbThe number of UL symbols among the symbols. In this case, the DL symbols of the time slot can be continuously configured with the first symbol to the i-th symbol of the time slot. In addition, the UL symbols of the time slot can be continuously configured with the j-th symbol to the last symbol of the time slot (where i < j). In the time slot, the symbol that is not configured with any of the UL symbols and DL symbols is a flexible symbol.

[0072] The type of symbol configured with the above RRC signal can be referred to as a semi-static DL / UL configuration. In the semi-static DL / UL configuration previously configured with the RRC signal, the flexible symbol can be indicated as a DL symbol, a UL symbol, or a flexible symbol by the dynamic time slot format information (SFI) sent on the physical downlink control channel (PDCCH). In this case, the DL symbol or UL symbol configured with the RRC signal does not change to another symbol type. Table 1 illustrates the dynamic SFI that the base station can indicate to the UE.

[0073] [Table 1]

[0074]

[0075] In Table 1, D represents a DL symbol, U represents a UL symbol, and X represents a flexible symbol. As shown in Table 1, up to two DL / UL switches can be allowed in one time slot.

[0076] Figure 3 is a diagram for explaining the physical channels used in a 3GPP system (e.g., NR) and a typical signal transmission method using the physical channel.

[0077] If the power of the UE is turned on or the UE camps on a new cell, the UE performs initial cell search (S101). Specifically, the UE can synchronize with the BS during the initial cell search. To this end, the UE can receive the primary synchronization signal (PSS) and the secondary synchronization signal (SSS) from the base station to synchronize with the base station, and obtain information such as the cell ID. Thereafter, the UE can receive the physical broadcast channel from the base station and obtain the broadcast information in the cell.

[0078] After the initial cell search is completed, the UE receives the physical downlink shared channel (PDSCH) according to the physical downlink control channel (PDCCH) and the information in the PDCCH, so that the UE can obtain more specific system information than the system information obtained through the initial cell search (S102). Here, the system information received by the UE is the cell common system information in radio resource control (RRC) for the UE to operate properly at the physical layer, and is referred to as the remaining system information (RSMI) or system information block (SIB)1.

[0079] When a UE initially accesses a base station or does not have radio resources for signal transmission (when the UE is in RRC_IDLE mode), the UE can perform a random access procedure to the base station (operations S103 to S106). First, the UE can send a preamble via the Physical Random Access Channel (PRACH) (S103) and receive a Random Access Response (RAR) message for the preamble from the base station via the PDCCH and the corresponding PDSCH (S104). In this case, the preamble in steps S103 and S104 can be described as message 1 (Msg1), and the random access response can be described as a response message or message 2 (Msg2). When the UE receives a valid random access response message, the UE sends data including the UE's identifier to the base station via the Physical Uplink Shared Channel (PUSCH) indicated by the UL license sent from the base station via the PDCCH (S105). In this case, the data including its own identifier from step S105 and the PUSCH including that data can be described as message 3 (Msg3). Furthermore, the PUSCH including this data can be described as message 3PUSCH (Msg3 PUSCH). Next, the UE waits for the reception of the PDCCH as an indication from the base station for conflict resolution. When the UE successfully receives the PDCCH and the corresponding PDSCH through its own identifier (S106), the random access procedure ends. In this case, the PDCCH and PDSCH in step S106 can be described as message 4 (Msg 4). During the random access procedure, the UE can obtain UE-specific system information necessary for proper operation at the physical layer at the RRC layer. When the UE obtains the UE-specific system information from the RRC layer, the UE enters the RRC_CONNECTED mode.

[0080] The RRC layer is used for message generation and management to control communication between the UE and the Radio Access Network (RAN). More specifically, in the RRC layer, the base station and UE can perform broadcasting of cell system information, management of paging message delivery, mobility management and handover, measurement reporting and its control, UE capability management, and storage management, including necessary management of existing data for all UEs in the cell. Typically, because the updates of signals transmitted from the RRC layer (hereinafter referred to as RRC signals) are longer than the transmission / reception period (i.e., transmission time interval, TTI) in the physical layer, RRC signals can remain unchanged for extended periods.

[0081] Following the above process, the UE receives the PDCCH / PDSCH (S107) and transmits the Physical Uplink Shared Channel (PUSCH) / Physical Uplink Control Channel (PUCCH) (S108) as a general UL / DL signal transmission process. Specifically, the UE can receive downlink control information (DCI) via the PDCCH. The DCI may include control information for the UE, such as resource allocation information. Furthermore, the format of the DCI can vary depending on the intended purpose. The uplink control information (UCI) transmitted by the UE to the base station via the UL includes DL / UL ACK / NACK signals, Channel Quality Indicator (CQI), Precoding Matrix Index (PMI), Rank Indicator (RI), etc. Here, CQI, PMI, and RI can be included in the Channel State Information (CSI). In a 3GPP NR system, the UE can transmit control information such as the aforementioned HARQ-ACK and CSI via the PUSCH and / or PUCCH.

[0082] Figure 4a and Figure 4b The diagram illustrates the SS / PBCH block used for initial cell access in a 3GPP NR system.

[0083] When power is on or when the UE wants to connect to a new cell, it can obtain time and frequency synchronization with that cell and perform an initial cell search procedure. The UE can detect the physical cell identifier N of the cell during the cell search procedure. cell ID Therefore, the UE can receive synchronization signals from the base station, such as the primary synchronization signal (PSS) and secondary synchronization signal (SSS), and synchronize with the base station. In this case, the UE can obtain information such as the cell identifier (ID).

[0084] refer to Figure 4a This section will describe synchronization signals (SS) in more detail. Synchronization signals can be classified into PSS and SSS. PSS can be used to obtain time-domain synchronization and / or frequency-domain synchronization, such as OFDM symbol synchronization and slot synchronization. SSS can be used to obtain frame synchronization and cell group ID. (Reference) Figure 4aAccording to Table 2, the SS / PBCH block can be configured with 20 consecutive RBs (=240 subcarriers) on the frequency axis and 4 consecutive OFDM symbols on the time axis. In this case, within the SS / PBCH block, the PSS is transmitted in the first OFDM symbol via subcarriers 56 to 182, and the SSS is transmitted in the third OFDM symbol. Here, the lowest subcarrier index of the SS / PBCH block is numbered starting from 0. In the first OFDM symbol for transmitting the PSS, the base station does not transmit signals via the remaining subcarriers, i.e., subcarriers 0 to 55 and subcarriers 183 to 239. Furthermore, in the third OFDM symbol for transmitting the SSS, the base station does not transmit signals via subcarriers 48 to 55 and subcarriers 183 to 191. The base station transmits the Physical Broadcast Channel (PBCH) via the remaining REs in the SS / PBCH block, excluding the signals mentioned above.

[0085] [Table 2]

[0086]

[0087] The SS allows a total of 1008 unique physical layer cell IDs to be divided into 336 physical layer cell identifier groups through a combination of three PSSs and SSSs. Each group includes three unique identifiers, specifically ensuring that each physical layer cell ID is only a part of one physical layer cell identifier group. Therefore, the physical layer cell ID N cell ID =3N (1) ID +N (2) ID An index N, ranging from 0 to 335, can be used to indicate the physical layer cell identifier group. (1) ID and an index N indicating the range of physical layer identifiers in the physical layer cell identifier group from 0 to 2. (2) ID Uniquely defined. The UE can detect the PSS and identify one of three unique physical layer identifiers. Furthermore, the UE can detect the SSS and identify one of 336 physical layer cell IDs associated with the physical layer identifier. In this case, the sequence d of the PSS... PSS (n) is as follows.

[0088] d PSS (n) = 1 - 2x(m)

[0089] 0 ≤ n < 127

[0090] Here, x(i+7) = (x(i+4) + x(i)) mod 2

[0091] And it is given as [x(6) x(5) x(4) x(3) x(2) x(1) x(0)]=[1 1 1 0 1 1 0].

[0092] In addition, the sequence d of SSS SSS (n) is as follows.

[0093] d SSS (n)=[1-2x0((n+m0)mod127)][1-2x1((n+m1)mod127)]

[0094]

[0095] 0 ≤ n < 127

[0096] x0(i+7)=(x0(i+4)+x0(i))mod2

[0097] Here, x1(i+7) = (x1(i+1) + x1(i)) mod 2, and is given as

[0098] [x0(6) x0(5) x0(4) x0(3) x0(2) x0(1) x0(0)]=[0 0 0 0 0 0 1]

[0099] [x1(6) x1(5) x1(4) x1(3) x1(2) x1(1) x1(0)]=[0 0 0 0 0 0 1]

[0100] A radio frame with a length of 10ms can be divided into two half-frames with a length of 5ms each. (Reference) Figure 4bThis section describes the time slots for transmitting the SS / PBCH block in each half-frame. The time slot for transmitting the SS / PBCH block can be any of cases A, B, C, D, and E. In case A, the subcarrier spacing is 15 kHz and the start time of the SS / PBCH block is the ({2,8}+14*n)th symbol. In this case, at carrier frequencies of 3 GHz or lower, n = 0 or 1. Furthermore, at carrier frequencies above 3 GHz and below 6 GHz, n can be 0, 1, 2, or 3. In case B, the subcarrier spacing is 30 kHz and the start time of the SS / PBCH block is {4,8,16,20}+28*n. In this case, at carrier frequencies of 3 GHz or lower, n = 0. Furthermore, at carrier frequencies above 3 GHz and below 6 GHz, n can be 0 or 1. In case C, the subcarrier spacing is 30 kHz and the start time of the SS / PBCH block is the ({2,8}+14*n)th symbol. In this case, at carrier frequencies of 3 GHz or lower, n = 0 or 1. Furthermore, at carrier frequencies above 3 GHz but below 6 GHz, n can be 0, 1, 2, or 3. In case D, the subcarrier spacing is 120 kHz and the start time of the SS / PBCH block is the ({4,8,16,20}+28*n)th symbol. In this case, at carrier frequencies of 6 GHz or higher, n = 0, 1, 2, 3, 5, 6, 7, 8, 10, 11, 12, 13, 15, 16, 17, 18. In case E, the subcarrier spacing is 240 kHz and the start time of the SS / PBCH block is the ({8,12,16,20,32,36,40,44}+56*n)th symbol. In this case, at carrier frequencies of 6 GHz or higher, n = 0, 1, 2, 3, 5, 6, 7, 8.

[0101] Figure 5a and Figure 5b The diagram illustrates the process of transmitting control information and using the control channel in a 3GPP NR system. (Reference) Figure 5aThe base station can add a Cyclic Redundancy Check (CRC) masked with a Radio Network Temporary Identifier (RNTI) (e.g., XOR operation) to the control information (e.g., downlink control information (DCI)) (S202). The base station can scramble the CRC with an RNTI value determined according to the purpose / objective of each control information. The common RNTI used by one or more UEs can include at least one of System Information RNTI (SI-RNTI), Paging RNTI (P-RNTI), Random Access RNTI (RA-RNTI), and Transmit Power Control RNTI (TPC-RNTI). In addition, UE-specific RNTIs can include at least one of Cell Temporary RNTI (C-RNTI) and CS-RNTI. Thereafter, the base station can perform rate matching according to the amount of resources used for PDCCH transmission after performing channel coding (e.g., polarity coding) (S204) (S206). Thereafter, the base station can multiplex the DCI based on the PDCCH structure based on Control Channel Elements (CCE) (S208). Furthermore, the base station can apply additional processes such as scrambling, modulation (e.g., QPSK), interleaving, etc., to the multiplexed DCI (S210), and then map the DCI to the resources to be transmitted. CCE is the basic resource unit used for PDCCH, and a CCE can include multiple (e.g., six) resource element groups (REGs). A REG can be configured with multiple (e.g., 12) REs. The number of CCEs used for a PDCCH can be defined as the aggregation level. In 3GPPNR systems, aggregation levels of 1, 2, 4, 8, or 16 can be used. Figure 5b This is a diagram relating to CCE aggregation levels and PDCCH multiplexing, illustrating the type of CCE aggregation level used for a PDCCH and the CCEs sent in the control area accordingly.

[0102] Figure 6 The diagram shows a control resource set (CORESET) in a 3GPP NR system that can transmit the Physical Downlink Control Channel (PDCCH).

[0103] A CORESET is a time-frequency resource in which PDCCH (i.e., control signals for the UE) is transmitted. Furthermore, a search space, described later, can be mapped to a CORESET. Therefore, the UE can monitor the time-frequency domain designated as a CORESET instead of all frequency bands used for PDCCH reception and decode the PDCCH mapped to the CORESET. The base station can configure one or more CORESETs for each cell for the UE. A CORESET can be configured with up to three consecutive symbols on the time axis. Additionally, a CORESET can be configured in units of six consecutive PRBs on the frequency axis. In the embodiment of Figure 5, CORESET#1 is configured with consecutive PRBs, while CORESET#2 and CORESET#3 are configured with discontinuous PRBs. A CORESET can reside in any symbol of a time slot. For example, in the embodiment of Figure 5, CORESET#1 begins at the first symbol of the time slot, CORESET#2 begins at the fifth symbol of the time slot, and CORESET#9 begins at the ninth symbol of the time slot.

[0104] Figure 7 The diagram illustrates a method for setting up the PUCCH search space in a 3GPP NR system.

[0105] To transmit PDCCH to a UE, each CORESET may have at least one search space. In embodiments of this disclosure, the search space is the set of all time-frequency resources (hereinafter referred to as PDCCH candidates) capable of being used to transmit a UE's PDCCH. The search space may include a common search space that requires UEs of 3GPP NR to search together and a terminal-specific search space or UE-specific search space that requires a specific UE to search. In the common search space, a UE may monitor a PDCCH that is configured to be searched together by all UEs belonging to the same base station cell. Furthermore, a UE-specific search space may be set for each UE, such that the UE monitors the PDCCH allocated to each UE at search space locations that differ depending on the UE. In the case of a UE-specific search space, the search spaces between UEs may partially overlap and be allocated due to the limited control area that can be allocated PDCCH. Monitoring the PDCCH includes blind decoding of PDCCH candidates in the search space. When blind decoding is successful, it can be expressed as (successfully) detecting / receiving the PDCCH, and when blind decoding fails, it can be expressed as not detecting / receiving or not successfully detecting / receiving the PDCCH.

[0106] For ease of explanation, a PDCCH scrambled with a Group Common (GC) RNTI previously known to one or more UEs to transmit DL control information to one or more UEs is called a Group Common (GC) PDCCH or a common PDCCH. Furthermore, a PDCCH scrambled with a RNTI of a specific terminal already known to a specific UE to transmit UL scheduling information or DL ​​scheduling information to that specific UE is called a UE-specific PDCCH. Common PDCCHs can be included in the common search space, and UE-specific PDCCHs can be included in either the common search space or the UE-specific PDCCH.

[0107] The base station can signal to each UE or group of UEs via the PDSCH information regarding resource allocation for the Paging Channel (PCH) and Downlink Shared Channel (DL-SCH) as transport channels (i.e., DL clearance) or resource allocation for the Uplink Shared Channel (UL-SCH) and Hybrid Automatic Repeat Request (HARQ) (i.e., UL clearance). The base station can transmit PCH transport blocks and DL-SCH transport blocks via the PDSCH. The base station can also transmit data excluding specific control information or specific service data via the PDSCH. Furthermore, the UE can receive data excluding specific control information or specific service data via the PDSCH.

[0108] The base station can include information in the PDCCH about which UE (one or more UEs) the PDSCH data is sent to and how the PDSCH data will be received and decoded by the corresponding UE, and then send the PDCCH. For example, suppose the DCI sent on a particular PDCCH is CRC masked with RNTI "A", and the DCI indicates that the PDSCH is allocated to radio resource "B" (e.g., frequency location) and indicates transmission format information "C" (e.g., transport block size, modulation scheme, coding information, etc.). The UE uses the RNTI information it possesses to monitor the PDCCH. In this case, if there is a UE performing blind decoding of the PDCCH using RNTI "A", then that UE receives the PDCCH and, based on the information in the received PDCCH, receives the PDSCH indicated by "B" and "C".

[0109] Table 3 shows an example of the Physical Uplink Control Channel (PUCCH) used in a wireless communication system.

[0110] [Table 3]

[0111] PUCCH format Length of OFDM symbol Number of bits 0 1-2 ≤2 1 4-14 ≤2 2 1-2 >2 3 4-14 >2 4 4-14 >2

[0112] PUCCH can be used to send the following UL control information (UCI).

[0113] - Scheduling Request (SR): Information used to request UL UL-SCH resources.

[0114] -HARQ-ACK: A response to the PDCCH (indicating DL SPS release) and / or to a DL transport block (TB) on the PDSCH. HARQ-ACK indicates whether information transmitted on the PDCCH or PDSCH has been received. HARQ-ACK responses include positive ACK (simply ACK), negative ACK (NACK hereinafter), discontinuous transmission (DTX), or NACK / DTX. Here, the terms HARQ-ACK are used interchangeably with HARQ-ACK / NACK and ACK / NACK. Typically, ACK can be represented by a bit value of 1, while NACK can be represented by a bit value of 0.

[0115] - Channel State Information (CSI): Feedback information about the DL channel. The UE generates it based on the CSI-reference signal (RS) transmitted by the base station. MIMO-related feedback information includes the Rank Indicator (RI) and the Precoding Matrix Indicator (PMI). The CSI can be divided into CSI Part 1 and CSI Part 2 based on the information indicated by the CSI.

[0116] In the 3GPP NR system, five PUCCH formats can be used to support various service scenarios, channel environments, and frame structures.

[0117] PUCCH format 0 is a format capable of transmitting 1 or 2 bits of HARQ-ACK information or SR. PUCCH format 0 can be transmitted using one or two OFDM symbols on the time axis and one PRB on the frequency axis. When transmitting PUCCH format 0 in two OFDM symbols, the same sequence on both symbols can be transmitted using different RBs. In this case, the sequence can be a cyclically shifted (CS) sequence from the base sequence used for PUCCH format 0. This allows the UE to obtain frequency diversity gain. Specifically, the UE can, according to M... bit Bit UCI (M) bit =1 or 2) to determine the cyclic shift (CS) value m cs Furthermore, the 12-length base sequence is based on a predetermined CS value m. cs The cyclically shifted sequence can be mapped to one OFDM symbol of one RB and 12 REs and transmitted. When the number of cyclic shifts available to the UE is 12 and M... bit When M = 1, 1 bit UCI 0 and 1 can be mapped to two cyclic shift sequences with a difference of 6, respectively. Furthermore, when M... bitWhen = 2, the 2-bit UCI 00, 01, 11 and 10 can be mapped to four cyclic shift sequences with a difference of 3 in their cyclic shift values.

[0118] PUCCH format 1 can deliver 1 or 2 bits of HARQ-ACK information or SR. PUCCH format 1 can be transmitted using consecutive OFDM symbols on the time axis and one PRB on the frequency axis. Here, the number of OFDM symbols occupied by PUCCH format 1 can be one of 4 to 14. More specifically, it can be used for M... bit BPSK modulation is performed using a UCI of 1. The UE can then use Quadrature Phase Shift Keying (QPSK) to modulate the M... bit Modulation is performed using a UCI of 2. The signal is obtained by multiplying the modulated complex-valued symbol d(0) by a sequence of length 12. In this case, the sequence can be the base sequence used for PUCCH format 0. The UE transmits the obtained signal by extending the even-numbered OFDM symbols assigned to PUCCH format 1 with a time-axis orthogonal cover code (OCC). PUCCH format 1 determines the maximum number of different UEs multiplexed in an RB based on the length of the OCC to be used. The demodulation reference signal (DMRS) can be extended with the OCC and mapped to the odd-numbered OFDM symbols of PUCCH format 1.

[0119] PUCCH Format 2 can deliver more than 2 bits of UCI. PUCCH Format 2 can be transmitted via one or two OFDM symbols on the time axis and one or more RBs on the frequency axis. When transmitting PUCCH Format 2 in two OFDM symbols, the sequences transmitted in different RBs through the two OFDM symbols can be identical. Here, the sequence can be multiple modulated complex-valued symbols d(0), ..., d(M). symbol -1). Here, M symbol It can be M bit / 2. Through this, the UE can obtain frequency diversity gain. More specifically, for M... bit Bit UCI (M) bit >2) Perform bit-level scrambling, QPSK modulation, and map it to one or two OFDM symbols' RBs. Here, the number of RBs can be one from 1 to 16.

[0120] PUCCH format 3 or PUCCH format 4 can deliver more than 2 bits of UCI. PUCCH format 3 or PUCCH format 4 can be transmitted using consecutive OFDM symbols on the time axis and one PRB on the frequency axis. The number of OFDM symbols occupied by PUCCH format 3 or PUCCH format 4 can be one of 4 to 14. Specifically, the UE utilizes e / 2-binary phase shift keying (BPSK) or QPSK to transmit M... bit Bit UCI (M) bit >2) Modulate to generate complex numerical symbols d(0) to d(M) symb -1). Here, when using π / 2-BPSK, M symb =M bit However, when using QPSK, M symb =M bit / 2. The UE may not apply block unit extension to PUCCH format 3. However, the UE may use a 12-length PreDFT-OCC to apply block unit extension to one RB (i.e., 12 subcarriers), allowing PUCCH format 4 to have two or four multiplexing capabilities. The UE performs transmit precoding (or DFT precoding) on ​​the extended signal and maps it to each RE to transmit the extended signal.

[0121] In this scenario, the number of Restricted Blocks (RBs) occupied by PUCCH format 2, PUCCH format 3, or PUCCH format 4 can be determined based on the length of the UCI sent by the UE and the maximum coding rate. When the UE uses PUCCH format 2, it can send HARQ-ACK and CSI information together via PUCCH. When the number of RBs that the UE can send exceeds the maximum number of RBs that can be used with PUCCH format 2, PUCCH format 3, or PUCCH format 4, the UE can send only the remaining UCI information without sending some UCI information, based on the priority of the UCI information.

[0122] PUCCH format 1, PUCCH format 3, or PUCCH format 4 can be configured using the RRC signal to indicate frequency hopping in the time slot. When frequency hopping is configured, the index of the RB to be hopped can be configured using the RRC signal. When PUCCH format 1, PUCCH format 3, or PUCCH format 4 is transmitted over N OFDM symbols on the time axis, the first hop can have floor (N / 2) OFDM symbols and the second hop can have ceiling (N / 2) OFDM symbols.

[0123] PUCCH format 1, PUCCH format 3, or PUCCH format 4 can be configured to be repeatedly transmitted in multiple time slots. In this case, the number K of time slots in which the PUCCH is repeatedly transmitted can be configured via an RRC signal. The repeatedly transmitted PUCCH must begin at a constant position in the OFDM symbol within each time slot and have a constant length. When one of the OFDM symbols in the time slot where the UE should transmit the PUCCH is indicated as a DL symbol via an RRC signal, the UE can choose not to transmit the PUCCH in the corresponding time slot and delay the transmission of the PUCCH to the next time slot.

[0124] In 3GPP NR systems, a UE can perform transmission / reception using a bandwidth less than or equal to the carrier (or cell) bandwidth. For this purpose, the UE can be configured with a bandwidth portion (BWP) consisting of a continuous bandwidth comprising a portion of the carrier's bandwidth. A UE operating under TDD or in unpaired spectrum can receive up to four DL / UL BWP pairs for one carrier (or cell). Furthermore, a UE can activate one DL / UL BWP pair. A UE operating under FDD or in paired spectrum can receive up to four DL BWPs on a downlink carrier (or cell) and up to four UL BWPs on an uplink carrier (or cell). For each carrier (or cell), the UE can activate one DL BWP and one UL BWP. The UE may not receive or transmit in time-frequency resources other than the activated BWPs. The activated BWP can be referred to as the active BWP.

[0125] The base station can indicate the active BWP among the BWPs configured by the UE via downlink control information (DCI). The BWP indicated by the DCI is activated, while other configured BWPs are deactivated. In a TDD-operated carrier (or cell), the base station can include a Bandwidth Part Indicator (BPI) indicating the active BWP in the DCI of the scheduling PDSCH or PUSCH to change the UE's DL / UL BWP pair. The UE can receive the DCI of the scheduling PDSCH or PUSCH and can identify the active DL / UL BWP pair based on the BPI. In the case of a downlink carrier (or cell) operating in FDD, the base station can include a BPI indicating the active BWP in the DCI of the scheduling PDSCH to change the UE's DL BWP. In the case of an uplink carrier (or cell) operating in FDD, the base station can include a BPI indicating the active BWP in the DCI of the scheduling PUSCH to change the UE's UL BWP.

[0126] Figure 8 This is a conceptual diagram illustrating carrier aggregation.

[0127] Carrier aggregation is a method in which a UE uses multiple frequency blocks or (in a logical sense) cells configured with UL resources (or component carriers) and / or DL ​​resources (or component carriers) as a large logical band so that the wireless communication system can use a wider bandwidth. A component carrier can also be referred to by the terms primary cell (PCell), secondary cell (SCell), or primary SCell (PScell). However, for convenience, the term "component carrier" will be used below.

[0128] refer to Figure 8 As an example of a 3GPP NR system, the entire system bandwidth can include up to 16 component carriers, and each component carrier can have a bandwidth of up to 400 MHz. Component carriers can include one or more physically contiguous subcarriers. Although in Figure 8 The diagram shows each component carrier with the same bandwidth, but this is merely an example, and each component carrier can have a different bandwidth. Furthermore, although each component carrier is shown as adjacent to each other on the frequency axis, the diagram is shown conceptually, and each component carrier can be physically adjacent to each other or spaced apart.

[0129] Different center frequencies can be used for each component carrier. Alternatively, a common center frequency can be used for physically adjacent component carriers. Assuming in Figure 8 In one embodiment, all component carriers are physically adjacent, so center frequency A can be used in all component carriers. Alternatively, assuming that the component carriers are not physically adjacent to each other, then center frequency A and center frequency B can be used in each component carrier.

[0130] When extending the total system bandwidth through carrier aggregation, the bandwidth used for communication with each UE can be defined on a component carrier basis. UE A can use 100MHz as the total system bandwidth and perform communication using all five component carriers. UEs B1-B5 can perform communication using only 20MHz bandwidth and one component carrier. UEs C1 and C2 can each use 40MHz bandwidth and two component carriers for communication. These two component carriers can be logically / physically adjacent or non-adjacent. UE C1 represents the case of using two non-adjacent component carriers, while UE C2 represents the case of using two adjacent component carriers.

[0131] Figure 9 This is a diagram used to illustrate single-carrier and multi-carrier communication. Specifically, Figure 9 (a) shows the single-carrier subframe structure and Figure 9 (b) shows the multi-carrier subframe structure.

[0132] refer to Figure 9(a) In FDD mode, a typical wireless communication system can perform data transmission or reception using a DL band and a corresponding UL band. In another specific embodiment, in TDD mode, the wireless communication system can divide radio frames into UL time units and DL time units in the time domain, and perform data transmission or reception using the UL / DL time units. (See reference...) Figure 9 (b) It is possible to aggregate three 20MHz component carriers (CCs) into each of the UL and DL, enabling a bandwidth of 60MHz. Each CC can be adjacent to or not adjacent to each other in the frequency domain. Figure 9 (b) illustrates a case where the bandwidth of the ULCC and DLCC are the same and symmetrical, but the bandwidth of each CC can be determined independently. Furthermore, asymmetric carrier aggregation with different numbers of UL CCs and DL CCs is possible. The DL / UL CCs allocated / configured to a specific UE via RRC can be referred to as the serving DL / UL CCs for that specific UE.

[0133] A base station can communicate with a UE by activating some or all of the UE's serving CCs or by deactivating some CCs. The base station can change the CCs to be activated / deactivated, and can change the number of CCs to be activated / deactivated. If the base station allocates CCs available to the UE as cell-specific or UE-specific, at least one of the allocated CCs will not be deactivated unless the CC allocation for the UE is completely reconfigured or the UE is handed over. A CC that is not deactivated by the UE is called the primary CC (PCC) or primary cell (PCell), while CCs that the base station can freely activate / deactivate are called secondary CCs (SCCs) or secondary cells (SCells).

[0134] Meanwhile, 3GPP NR uses the concept of cells to manage radio resources. A cell is defined as a combination of DL resources and UL resources, i.e., a combination of DL CC and UL CC. A cell can be configured with DL resources alone, or it can be configured with a combination of DL resources and UL resources. When carrier aggregation is supported, the link between the carrier frequencies of DL resources (or DL ​​CC) and UL resources (or UL CC) can be indicated by system information. The carrier frequency refers to the center frequency of each cell or CC. The cell corresponding to a PCC is called a PCell, and the cell corresponding to an SCC is called an SCell. The carrier corresponding to a PCell in DL is the DL PCC, and the carrier corresponding to a PCell in UL is the UL PCC. Similarly, the carrier corresponding to an SCell in DL is the DL SCC, and the carrier corresponding to an SCell in UL is the UL SCC. Depending on the UE's capabilities, a serving cell can be configured with one PCell and zero or more SCells. In the case of a UE in the RRC_CONNECTED state but not configured for carrier aggregation or not supporting carrier aggregation, only one serving cell is configured with only a PCell.

[0135] As mentioned above, the term "cell" used in carrier aggregation is distinguished from the term "cell" referring to a geographical area that provides communication services through a base station or an antenna array. That is, a component carrier can also be referred to as a scheduled cell, a scheduled cell, a primary cell (PCell), a secondary cell (SCell), or a primary SCell (PScell). However, to distinguish between cells representing a geographical area and cells in carrier aggregation, in this disclosure, cells in carrier aggregation are referred to as CCs, and cells representing a geographical area are referred to as cells.

[0136] Figure 10 This diagram illustrates an example of cross-carrier scheduling technology. When cross-carrier scheduling is set up, the control channel transmitted via the first CC can use the Carrier Indicator Field (CIF) to schedule the data channel transmitted via either the first CC or the second CC. The CIF is included in the DCI. In other words, a scheduling cell is set up, and the DL license / UL license transmitted in the PDCCH area of ​​that scheduling cell schedules the PDSCH / PUSCH of the scheduled cell. That is, there is a search area for multiple component carriers in the PDCCH area of ​​the scheduling cell. A PCell can essentially be a scheduling cell, and a specific SCell can be designated as a scheduling cell by a higher layer.

[0137] exist Figure 10In the embodiment, it is assumed that three DL CCs are combined. Here, it is assumed that DL component carrier #0 is a DLPCC (or PCell), and DL component carriers #1 and #2 are DL SCCs (or SCells). Furthermore, it is assumed that the DLPCC is configured as a PDCCH monitoring CC. When cross-carrier scheduling is not configured via UE-specific (or UE group-specific or cell-specific) higher-layer signaling, CIF is disabled, and each DL CC can transmit only the PDCCH for scheduling its PDSCH according to the NR PDCCH rules without CIF (non-cross-carrier scheduling, self-carrier scheduling). Meanwhile, if cross-carrier scheduling is configured via UE-specific (or UE group-specific or cell-specific) higher-layer signaling, CIF is enabled, and a specific CC (e.g., DL PCC) can use CIF to transmit not only the PDCCH for scheduling DL CC A but also the PDCCH for scheduling another CC (cross-carrier scheduling). On the other hand, no PDCCH is transmitted in another DL CC. Therefore, the UE monitors the PDCCH excluding CIF to receive the PDSCH of self-carrier scheduling depending on whether cross-carrier scheduling is configured for the UE, or monitors the PDCCH including CIF to receive the PDSCH of cross-carrier scheduling.

[0138] on the other hand, Figure 9 and Figure 10 The diagram illustrates the subframe structure of a 3GPP LTE-A system, and the same or similar configuration can be applied to a 3GPP NR system. However, in a 3GPP NR system, Figure 9 and Figure 10 Subframes can be replaced with time slots.

[0139] Figure 11 This is a block diagram illustrating the configuration of a UE and a base station according to an embodiment of the present disclosure.

[0140] In embodiments of this disclosure, the UE can be implemented using various types of wireless communication devices or computing devices that are guaranteed to be portable and mobile. The UE can be referred to as User Equipment (UE), Station (STA), Mobile Subscriber (MS), etc. Furthermore, in embodiments of this disclosure, the base station controls and manages cells (e.g., macro cells, femtocells, picocells, etc.) corresponding to the service area, and performs functions such as signal transmission, channel designation, channel monitoring, self-diagnosis, and relaying. The base station can be referred to as Next Generation Node B (gNB) or Access Point (AP).

[0141] As shown in the accompanying drawings, the UE 100 according to an embodiment of the present disclosure may include a processor 110, a communication module 120, a memory 130, a user interface 140, and a display unit 150.

[0142] First, the processor 110 can execute various instructions or procedures and process data within the UE 100. Furthermore, the processor 110 can control the overall operation of each unit including the UE 100 and can control the transmission / reception of data between the units. Here, the processor 110 can be configured to perform operations according to the embodiments described in this disclosure. For example, the processor 110 can receive time slot configuration information, determine a time slot configuration based on the time slot configuration information, and perform communication according to the determined time slot configuration.

[0143] Next, the communication module 120 can be an integrated module that uses a wireless communication network to perform wireless communication and uses a wireless LAN to perform wireless LAN access. For this purpose, the communication module 120 can include multiple network interface cards (NICs), such as cellular communication interface cards 121 and 122 and an unlicensed band communication interface card 123, either internally or externally. In the accompanying drawings, the communication module 120 is shown as a monolithic integrated module; however, unlike the drawings, each network interface card can be arranged independently depending on the circuit configuration or usage.

[0144] Cellular communication interface card 121 can transmit or receive radio signals with at least one of base station 200, external device, and server using a mobile communication network and provide cellular communication services in a first frequency band based on instructions from processor 110. According to an embodiment, cellular communication interface card 121 may include at least one NIC module using a frequency band less than 6 GHz. At least one NIC module of cellular communication interface card 121 can independently perform cellular communication with at least one of base station 200, external device, and server in accordance with cellular communication standards or protocols in a frequency band below 6 GHz supported by the corresponding NIC module.

[0145] Cellular communication interface card 122 can transmit or receive radio signals with at least one of base station 200, external device, and server using a mobile communication network and provide cellular communication services in a second frequency band based on instructions from processor 110. According to an embodiment, cellular communication interface card 122 may include at least one NIC module using a frequency band greater than 6 GHz. At least one NIC module of cellular communication interface card 122 can independently perform cellular communication with at least one of base station 200, external device, and server in accordance with cellular communication standards or protocols in a frequency band above 6 GHz supported by the corresponding NIC module.

[0146] The unlicensed frequency band communication interface card 123 transmits or receives radio signals with at least one of the base station 200, external devices, and servers by using a third frequency band that is an unlicensed frequency band, and provides unlicensed frequency band communication services based on instructions from the processor 110. The unlicensed frequency band communication interface card 123 may include at least one NIC module using an unlicensed frequency band. For example, the unlicensed frequency band may be a frequency band of 2.4 GHz, 5 GHz, 6 GHz, 7 GHz, or higher than 52.6 GHz. At least one NIC module of the unlicensed frequency band communication interface card 123 can independently or dependently perform wireless communication with at least one of the base station 200, external devices, and servers according to the unlicensed frequency band communication standard or protocol supported by the corresponding NIC module.

[0147] The memory 130 stores the control program used in the UE 100 and various data used therein. Such a control program may include a prescribed program required to perform wireless communication with at least one of the base station 200, external devices, and servers.

[0148] Next, the user interface 140 includes various input / output means provided in the UE 100. In other words, the user interface 140 can use various input means to receive user input, and the processor 110 can control the UE 100 based on the received user input. Furthermore, the user interface 140 can use various output means to execute output based on instructions from the processor 110.

[0149] Next, the display unit 150 outputs various images on the display screen. The display unit 150 can output various display objects, such as content executed by the processor 110 or a user interface, based on control instructions from the processor 110.

[0150] Furthermore, the base station 200 according to embodiments of the present disclosure may include a processor 210, a communication module 220, and a memory 230.

[0151] First, the processor 210 can execute various instructions or programs and process the internal data of the base station 200. Furthermore, the processor 210 can control the overall operation of each unit in the base station 200 and control the transmission and reception of data between the units. Here, the processor 210 can be configured to perform operations according to the embodiments described in this disclosure. For example, the processor 210 can notify time slot configurations with signals and perform communication based on the time slot configurations notified by the used signals.

[0152] Next, the communication module 220 can be an integrated module that uses a wireless communication network to perform wireless communication and uses a wireless LAN to perform wireless LAN access. For this purpose, the communication module 220 can include multiple network interface cards, such as cellular communication interface cards 221 and 222 and an unlicensed frequency band communication interface card 223, either internally or externally. In the accompanying drawings, the communication module 220 is shown as a monolithic integrated module; however, unlike the drawings, each network interface card can be arranged independently depending on the circuit configuration or usage.

[0153] Cellular communication interface card 221 can transmit or receive radio signals with at least one of base station 100, external device, and server using a mobile communication network and provide cellular communication services in a first frequency band based on instructions from processor 210. According to an embodiment, cellular communication interface card 221 may include at least one NIC module using a frequency band less than 6 GHz. At least one NIC module of cellular communication interface card 221 can independently perform cellular communication with at least one of base station 100, external device, and server in accordance with cellular communication standards or protocols in a frequency band less than 6 GHz supported by the corresponding NIC module.

[0154] Cellular communication interface card 222 can transmit or receive radio signals with at least one of base station 100, external device, and server using a mobile communication network and provide cellular communication services in a second frequency band based on instructions from processor 210. According to an embodiment, cellular communication interface card 222 may include at least one NIC module using a 6 GHz or higher frequency band. At least one NIC module of cellular communication interface card 222 can independently perform cellular communication with at least one of base station 100, external device, and server in accordance with cellular communication standards or protocols in a 6 GHz or higher frequency band supported by the corresponding NIC module.

[0155] The unlicensed frequency band communication interface card 223 transmits or receives radio signals with at least one of the base station 100, external devices, and servers by using a third frequency band that is an unlicensed frequency band, and provides unlicensed frequency band communication services based on instructions from the processor 210. The unlicensed frequency band communication interface card 223 may include at least one NIC module using an unlicensed frequency band. For example, the unlicensed frequency band may be a band of 2.4 GHz, 5 GHz, 6 GHz, 7 GHz, or a band higher than 52.6 GHz. At least one NIC module of the unlicensed frequency band communication interface card 223 can independently or dependently perform wireless communication with at least one of the base station 100, external devices, and servers in accordance with the unlicensed frequency band communication standards or protocols of the frequency band supported by the corresponding NIC module.

[0156] Figure 11This is a block diagram illustrating a UE 100 and a base station 200 according to an embodiment of the present disclosure, and the blocks shown individually are logically divided elements of the device. Therefore, the aforementioned elements of the device can be installed in a single chip or multiple chips depending on the device design. Furthermore, a portion of the configuration of the UE 100, such as a user interface 140, a display unit 150, etc., may be selectively provided in the UE 100. Additionally, the user interface 140, display unit 150, etc., may be additionally provided in the base station 200 if necessary.

[0157] Figure 12 The illustration shows a method for scheduling a physical uplink shared channel in the time domain according to an embodiment of the present disclosure.

[0158] A terminal can send uplink data to a base station via PUSCH. The base station can schedule (PUSCH scheduling) for the terminal to send uplink data via PUSCH. i) In the Dynamic Grant (DG) method, the base station can perform PUSCH scheduling via DCI included in the PDCCH. Alternatively, ii) in the Configuration Grant (CG) method, the terminal can send uplink data to the base station via PUSCH according to resources and transport methods pre-configured by the base station for the terminal.

[0159] In this scenario, the DCI included in the PDCCH may include PUSCH scheduling information. For example, the DCI may include time-domain information (Time Domain Resource Assignment (TDRA)) and frequency-domain information (Frequency Domain Resource Assignment (FDRA)). The terminal can receive the DCI transmitted in the control resource set and search space, and can perform operations indicated via the DCI (e.g., uplink data transmission via PUSCH). In this scenario, the DCI format used for PUSCH scheduling may be DCI formats 0_0, 0_1, and 0_2. The DCIs of formats 0_0, 0_1, and 0_2 may include a TDRA field containing time-domain information about the PUSCH. In this scenario, the time-domain information may include K2, which is the offset value between the time slot in which the PDCCH is transmitted from the base station and the time slot in which the PUSCH is transmitted by the terminal. Additionally, the DCI may include a start and length indication value (SLIV), which is a jointly encoded value of the start symbol index (S) of the PUSCH in the time slot indicated by K2 and the symbol length (L, number) of the PUSCH. If the terminal receives DCI in time slot n, then the time slot in which PUSCH is scheduled can be floor(n*2). μPUSCH / n*2 μPDCCHSlot n is defined as )+K2. μPUSCH and μPDCCH can refer to the subcarrier spacing (SCS) of the cell in which PUSCH is scheduled and the subcarrier spacing (SCS) of the cell in which the terminal receives PDCCH, respectively. floor(x) is a function that returns the largest integer equal to or less than x. In this specification, slot n can refer to the slot indexed by index n.

[0160] refer to Figure 12 In (a), the subcarrier spacing of the cell in which the terminal receives the PDCCH and the subcarrier spacing of the cell in which the PUSCH is scheduled can be the same. In this case, if the terminal receives the PDCCH in slot n and is indicated that K2 is 4, then the slot in which the PUSCH is scheduled can be slot n+K2, that is, slot n+4.

[0161] Regarding PUSCH scheduling types, two mapping types can exist: PUSCH mapping type A and PUSCH mapping type B. Depending on the PUSCH mapping type, the possible range of values ​​for the start symbol index and SLIV for the PUSCH can vary. In PUSCH mapping type A, resource allocation including only DMRS symbols is possible, and the DMRS symbols can be located in the third or fourth symbol of the slot based on values ​​indicated by higher layers. That is, in the case of PUSCH mapping type A, the index (S) of the start symbol of the PUSCH can be 0, and the length (L) of the PUSCH can have one of a value from 4 to 14 (12 for extended CP) depending on the DMRS symbol position. In PUSCH mapping type B, the first symbol of the PUSCH can be a DMRS symbol. Therefore, S can have a value from 0 to 13 (11 for extended CP), and L can have one of a value from 1 to 14 (12 for extended CP). Additionally, since a PUSCH cannot cross a slot boundary, the sum of S and L should be less than or equal to 14 (12 for extended CP).

[0162] refer to Figure 12 In (b), the base station can schedule PUSCH mapping type A where the third symbol is a DMRS symbol, the starting symbol index (S) is 0, and the length (L) is 7; it can schedule PUSCH mapping type A where the fourth symbol is a DMRS symbol, the starting symbol index (S) is 0, and the length (L) is 7; and it can schedule PUSCH mapping type B where the first symbol is a DMRS symbol, the starting symbol index (S) is 5, and the length (L) is 5. In this case, the frequency domain information of the PUSCH indicated in the FDRA field of DCI format 0_0, 0_1, or 0_2 can be divided into two types according to the frequency resource allocation type.

[0163] Figure 13 The illustration shows a method for scheduling a physical uplink shared channel in the frequency domain according to an embodiment of the present disclosure.

[0164] In the following text, reference will be made to Figure 13 Describes the frequency resource allocation type.

[0165] i) Frequency resource allocation type 0, as the first type, can be configured by bundling a certain number of PRBs according to the number of RBs included in the BWP configured (set) for the terminal, and indicating whether the RBG is used via a bitmap in units of RBGs. That is, the terminal can determine whether to use the corresponding RBG via a bitmap sent from the base station. The number of PRBs included in an RBG can be set (configured) from a higher layer, and the more RBs can be set (configured) as the number of RBs included in the BWP configured for the terminal increases. (See reference) Figure 13 In (a), the BWP size set (configured) for the terminal can be 72 PRBs, and an RBG can include 4 PRBs. In this case, the terminal can determine four PRBs as an RBG starting from PRB 0 in ascending order, and can index each RBG starting from 0. That is, an RBG including PRB0 to PRB 3 can be indexed as RBG 0, and an RBG including PRB 4 to PRB 7 can be indexed as RBG 1. Up to RBG17 can be indexed in the same way, where the base station can send 1 bit (0 or 1) per RBG to the terminal, i.e., a total of 18 bits, and the terminal can determine whether to use the PRBs constituting the corresponding RBG based on the received 18 bits. In this case, if the bit value is 0, the terminal can determine not to schedule PUSCH for any PRBs in the corresponding RBG. If the bit value is 1, the terminal can determine to schedule PUSCH for all PRBs in the corresponding RBG. In this case, the bit value can be applied in reverse. ii) As a second type of frequency resource allocation, type 1 can be a type indicating information about consecutive PRBs allocated based on the size of the terminal's active BWP or initial BWP. The information about consecutive PRBs can be a Resource Indication Value (RIV) value in which the start index (S) and length (L) of the consecutive PRBs are jointly encoded. (See reference) Figure 13 (b) When the BWP size is 50 PRBs, and PUSCH is scheduled for the terminal from PRB 2 to PRB 11 within those 50 PRBs, the starting index of consecutive PRBs can be 2 and the length can be 10. That is, the terminal can determine the starting index and length of consecutive PRBs in which PUSCH is scheduled based on the RIV value received from the base station. Specifically, this can be achieved through N... size BWP*(L-1)+S calculates the RIV. size BWP This could be the size of the BWP configured for the terminal. For example, if the RIV value received by the terminal is 452, then the calculation of 452 is based on 452 = 50 * (10 - 1) + 2, so the terminal can determine that the starting index of the consecutive PRBs in which the PUSCH is scheduled is 2 and the length is 10.

[0166] Using DCI format 0_1 ​​or 0_2 for scheduling PUSCH, a terminal can be configured from a higher layer to use only one of the aforementioned two frequency resource allocation types or to dynamically use both types. If the terminal is configured to dynamically use both types, the terminal can determine the type to use via the 1 bit of the most significant bit (MSB) of the FDRA field of the DCI.

[0167] There may be uplink shared channel transmission methods based on configuration licenses for URLLC transmissions. Configuration-licensed uplink shared channel transmission methods can be described as unlicensed transmission. A configuration-licensed uplink shared channel transmission method can be one where, if the base station configures available resources for uplink transmission for the terminal via a higher layer (i.e., RRC signaling), the terminal can transmit uplink shared channels using the configured resources. Depending on whether the DCI indicates activation and release, configuration-licensed uplink shared channel transmission methods can be classified into two types: i) Type 1 configuration-licensed uplink shared channel transmission methods can be methods where the transmission method and resources are pre-configured via a higher layer. ii) Type 2 configuration-licensed uplink shared channel transmission methods can be methods where configuration-licensed transmission is configured via a higher layer, and the method and resources for actual transmission are configured via the DCI.

[0168] The configuration-based uplink transmission method can support URLLC transmission. Therefore, uplink transmissions can be repeatedly performed on multiple time slots to ensure high reliability. In this case, the redundant version (RV) sequence can be one of {0,0,0,0}, {0,2,3,1}, and {0,3,0,3}, and the RV corresponding to the (mod(n-1,4)+1)th value can be used in the nth repetition. That is, the RV corresponding to the value obtained by adding 1 to the remainder of n-1 divided by 4 can be used. Additionally, a terminal configured to repeatedly transmit the uplink channel can start repetition only in the time slot where the RV value is 0. However, if the RV sequence is {0,0,0,0} and the uplink channel is configured to be repeatedly transmitted in 8 time slots, the terminal may not start repetition in the eighth time slot. The terminal can terminate repetition when a UL license with the same HARQ procedure ID is received, or when the number of repetitions configured via a higher layer is reached, or when the cycle is exceeded. The UL license can refer to the DCI used for PUSCH scheduling.

[0169] As mentioned above, in order to improve the reliability of PUSCH transmission / reception between base stations and terminals in a wireless communication system, the base station can configure the terminal to repeatedly transmit PUSCH.

[0170] Figure 14 The illustration shows repeated transmission of a physical uplink shared channel according to an embodiment of the present disclosure.

[0171] Repeated PUSCH transmissions performed by the terminal can have two types. i) First, repeated PUSCH transmission type A will be described. When the terminal receives a DCI of format 0_1 ​​or 0_2 included in the PDCCH used for PUSCH scheduling from the base station, the terminal can repeatedly transmit PUSCH over K consecutive time slots. The value of K can be configured from a higher layer or can be a value included in the TDRA field of the DCI for configuration by the terminal. For example, refer to... Figure 14(a) The terminal can receive the PDCCH for PUSCH scheduling in time slot n, and can configure the K2 value according to the DCI included in the received PDCCH. In this case, if the K2 value is 2 and the K value is 4, the terminal can start repeated PUSCH transmission in time slot n+K2, and can repeatedly send PUSCH until time slot n+K2+K-1. That is, the terminal starts repeated PUSCH transmission in time slot n+2 and repeatedly sends PUSCH until time slot n+5. In this case, the time domain resources and frequency domain resources for sending PUSCH in each time slot can be the same as those time domain resources and frequency domain resources indicated in the DCI. That is, PUSCH can be sent in the same symbols and PRBs within the time slot. ii) Next, repeated PUSCH transmission type B will be described. Repeated PUSCH transmission type B can be a type used by the terminal to perform low-latency repeated PUSCH transmission to meet URLLC requirements, etc. The terminal can be configured with the starting symbol (S) and length (L) of repeated PUSCH transmission via the TDRA field of the DCI sent by the base station. In this case, the starting symbol (S) and length (L) can be for a nominal PUSCH that is temporarily obtained, rather than for an actual PUSCH that is actually transmitted by the terminal. There may not be individual symbols between nominal PUSCHs that are configured to be transmitted repeatedly. That is, nominal PUSCHs can be consecutive in the time domain. The terminal can determine the actual PUSCH from the nominal PUSCH. A nominal PUSCH can be determined as one or more actual PUSCHs. The base station can configure symbols that cannot be used for repeated PUSCH transmission type B for the terminal. Symbols that cannot be used for repeated PUSCH transmission type B can be described as invalid symbols. The terminal can exclude invalid symbols from the resources configured to transmit nominal PUSCHs. As mentioned above, nominal PUSCHs are configured to be transmitted repeatedly on consecutive symbols, but if invalid symbols are excluded, the resources used for nominal PUSCH transmission become discontinuous. The actual PUSCH can be configured to be transmitted on consecutive symbols configured for a nominal PUSCH transmission, excluding invalid symbols. In this case, if consecutive symbols cross slot boundaries, the actual transmitted PUSCH can be partitioned based on the slot boundaries. Invalid symbols may include downlink symbols configured by the base station for the terminal. (See reference) Figure 14(b) The terminal can be scheduled to transmit a PUSCH of 5 symbols, starting from the twelfth symbol of the first time slot (time slot n), and can be configured to transmit four times in a Type B manner. In this case, the resources scheduled for the first nominal PUSCH (nominal #1) may include symbols (n,11), (n,12), (n,13), (n+1,0), and (n+1,1). The resources scheduled for the second nominal PUSCH (nominal #2) may include symbols (n+1,2), (n+1,3), (n+1,4), (n+1,5), and (n+1,6). The resources scheduled for the third nominal PUSCH (nominal #3) may include symbols (n+1,7), (n+1,8), (n+1,9), (n+1,10), and (n+1,11). The resources scheduled for the fourth nominal PUSCH (nominal #4) can include symbols (n+1, 12), (n+1, 13), (n+2, 0), (n+2, 1), and (n+2, 2). In this case, symbol (n, k) represents symbol k in slot n. That is, k can be a value from 0 to 13 for a normal CP, and a value from 0 to 11 for an extended CP. Invalid symbols can be configured as symbols 6 and 7 in slot n+1. In this case, to determine the actual PUSCH, the last symbol of the second nominal PUSCH (nominal #2) can be excluded, and the first symbol of the third nominal PUSCH (nominal #3) can be excluded. The first nominal PUSCH (nominal #1) can be divided into two actual PUSCHs (actual #1 and actual #2) that are actually transmitted, by the slot boundaries. Each of the second nominal PUSCH (nominal #2) and the third nominal PUSCH (nominal #3) can be distinguished into an actual PUSCH (actual #3 and actual #4) by combining consecutive symbols excluding invalid symbols. Finally, the fourth nominal PUSCH (nominal #4) is divided into two actually transmitted (actual) PUSCHs (actual #5 and actual #6) by time slot boundaries. The terminal transmits the last of the actually transmitted (actual) PUSCHs. An actual PUSCH should include at least one DMRS symbol. Therefore, when the repeated PUSCH transmission type B is configured, if the total length of the actual PUSCH is one symbol, the actual PUSCH can be omitted and not transmitted. This is because an actual PUSCH with one symbol may not include information other than DMRS.

[0172] To obtain diversity gain in the frequency domain, frequency hopping can be configured for uplink channel transmission.

[0173] For repeated PUSCH transmission type A, the terminal can be configured with either intra-slot frequency hopping (performing frequency hopping within a time slot) or inter-slot frequency hopping (performing frequency hopping within each time slot). If intra-slot frequency hopping is configured for the terminal, the terminal can split the PUSCH in the time domain within the time slot used to transmit the PUSCH and transmit one half of the PUSCH in the scheduled PRB, and can also transmit the other half in the PRB obtained by adding an offset value to the scheduled PRB. In this case, two or four offset values ​​can be configured via a higher layer based on the active BWP size, and one of these values ​​can be configured (indicated to the configuration) for the terminal via the DCI. If inter-slot frequency hopping is configured for the terminal, the terminal can transmit the PUSCH in the scheduled PRB in time slots with even-numbered time slot indices, and in the PRB obtained by adding an offset value to the scheduled PRB in odd-numbered time slots.

[0174] For repetitive PUSCH transmission type B, a terminal can be configured with either inter-repetitive frequency hopping (performing frequency hopping at nominal PUSCH boundaries) or inter-slot frequency hopping (performing frequency hopping within each time slot). If inter-repetitive frequency hopping is configured for the terminal, the terminal can transmit the actual PUSCH corresponding to odd-numbered nominal PUSCHs on the scheduled PRB, and the terminal can transmit the actual PUSCH corresponding to even-numbered nominal PUSCHs on the PRB obtained by adding an offset value to the scheduled PRB. In this case, two or four offset values ​​can be configured via a higher layer based on the active BWP size, and one of these values ​​can be configured (indicated to the configuration) for the terminal via the DCI. If inter-slot frequency hopping is configured for the terminal, the terminal can transmit PUSCHs in the scheduled PRB in time slots with even-numbered time slot indices, and in the PRB obtained by adding an offset value to the scheduled PRB in odd-numbered time slots.

[0175] When a terminal performs a repeated PUSCH transmission, if the symbols scheduled for PUSCH transmission in a specific time slot overlap with semi-statically configured DL symbols or symbols configured to receive SS / PBCH blocks, the terminal may not transmit the overlapping PUSCH in the time slot that includes the overlapping symbols. Additionally, the overlapping PUSCH may be delayed and may not be transmitted even in subsequent time slots.

[0176] If the terminal receives a DCI of format 1_0, 1_1, or 1_2 for PUCCH scheduling, the terminal needs to send a PUCCH to the base station. In this case, the PUCCH may include uplink control information (UCI), and the UCI may include at least one of HARQ-ACK, scheduling request (SR), and channel state information (CSI). The HARQ-ACK can be an indication of whether the terminal has successfully received one of two types of channels. The first type can be a HARQ-ACK for a PDSCH when the terminal is scheduled to receive a PDSCH via a DCI of format 1_0, 1_1, or 1_2. The second type can be a HARQ-ACK for a DCI when the DCI of format 1_0, 1_1, or 1_2 is a DCI indicating the release of a semi-persistently scheduled (SPS) PDSCH. For PUCCH transmissions that include HARQ-ACK, the "PDSCH-to-HARQ_feedback timing indicator" field of the DCI can indicate K1 as information (value) of the time slot in which the PUCCH is scheduled to be transmitted. Here, K1 can be a non-negative integer value. DCI format 1_0 can indicate one of {0, 1, 2, 3, 4, 5, 6, 7} as the K1 value. The K1 value that can be indicated in DCI formats 1_1 or 1_2 can be set (configured) from a higher layer.

[0177] The method for determining the time slot in which a PUCCH including a first-type HARQ-ACK is transmitted will be described. There may be uplink time slots that overlap with the last symbol of a PDSCH corresponding to a HARQ-ACK transmitted in that slot. In this case, if the index of the overlapping uplink time slot is m, the terminal can transmit a PUCCH including a HARQ-ACK on time slot m+K1. The index of the uplink time slot can be a value determined based on the subcarrier spacing of the BWP in which the PUCCH is transmitted. If the terminal is configured with downlink time slot aggregation, the last symbol of the PDSCH transmitted in that slot can refer to the last scheduled symbol within the last time slot in which the PDSCH is transmitted.

[0178] Figure 15 The figure illustrates a method for scheduling the physical uplink control channel according to an embodiment of the present disclosure.

[0179] refer to Figure 15The subcarrier spacing of the DL BWP receiving PDCCH, the subcarrier spacing of the DL BWP scheduling PDSCH, and the subcarrier spacing of the UL BWP transmitting PUCCH can be the same. The terminal can receive the PDCCH for scheduling PUCCH and PDSCH from the base station in time slot n. In this case, the K0 and K1 values ​​can be configured (indicated) as 2 and 3 respectively by the DCI included in the PDCCH received in the time slot. For example, if the last symbol of the PDSCH transmitted in this time slot is symbol n+K0 (i.e., symbol n+2), the terminal can transmit a HARQ-ACK for the PDSCH in time slot n+2+K1 (i.e., time slot n+5). In this case, the HARQ-ACK for the PDSCH can be included in the PUCCH.

[0180] Figure 16 The illustration shows repeated transmission of the physical uplink control channel according to an embodiment of the present disclosure.

[0181] To ensure wide coverage in NR systems, terminals can repeatedly transmit long PUCCHs across 2, 4, or 8 time slots. In this case, the long PUCCH format can be PUCCH format 1, 3, or 4. If the terminal repeatedly transmits the PUCCH, it can repeatedly transmit the same UCI in each time slot. (Reference) Figure 16 When PDSCH reception terminates in time slot n and K1 is 2, the terminal can transmit PUCCH in time slot n+K1 (i.e., time slot n+2). When the base station configures the number of repeated PUCCH transmissions to 4 (N... repeat PUCCH When n=4), the terminal can repeatedly transmit PUCCH from time slot n+2 to time slot n+5. In this case, the symbol configuration of the repeatedly transmitted PUCCH can be the same. That is, the repeatedly transmitted PUCCH can start with the same symbol in each time slot and can include the same number of symbols.

[0182] Even for PUCCH transmissions, frequency hopping can be applied to obtain diversity gain in the frequency domain. If intra-slot frequency hopping is applied, the terminal can split the time domain of the slot used for PUCCH transmission in half and transmit one half of the PUCCH on a first PRB, and the other half on a second PRB. The first and second PRBs can be configured via a higher layer for PUCCH resource configuration. If inter-slot frequency hopping is applied, the terminal can transmit PUCCH on a first PRB with an even-numbered slot index and on a second PRB with an odd-numbered slot index. Additionally, when the terminal performs repeated PUCCH transmissions, if the symbols of a specific slot scheduled for PUCCH transmission overlap with semi-statically configured DL symbols or symbols configured to receive SS / PBCH blocks, the terminal may not transmit PUCCH on the slot containing the overlapping symbols. The terminal can delay the transmission of the untransmitted PUCCH so that it can be transmitted in a subsequent slot. In this case, if the symbols of the time slot used for delayed PUCCH transmission do not overlap with the semi-statically configured DL symbols or the symbols configured to receive SS / PBCH blocks, the terminal may send PUCCH.

[0183] In the following, this disclosure proposes a method for solving coverage problems related to PUSCH transmissions performed by a terminal during a random access procedure between a terminal and a base station.

[0184] As referenced above Figure 3During random access, the terminal can transmit Msg3 PUSCH using an uplink grant (UL grant) included in the random access response (RAR or Msg2). The UL grant is information used to schedule the Msg3 PUSCH and may include a frequency hopping flag indicating frequency hopping information, Time Domain Resource Assignment (TDRA) information, Frequency Domain Resource Assignment (FDRA) information, Modulation and Coding Scheme (MCS) information, Transmission Power Control (TPC) command information for PUSCH transmission, CSI request information, and Channel Access-CPext information. The Msg3 PUSCH transmitted using the uplink grant included in Msg2 can be the initial transmission PUSCH. If the base station fails to receive the Msg3 PUSCH from the terminal, the base station can instruct the terminal to retransmit the Msg3 PUSCH. Retransmission of the Msg3 PUSCH can be indicated (scheduled) by the PDCCH, and the retransmission can be indicated by a DCI format 0_0 included in the PDCCH, which is scrambled by a temporary C-RNTI (TC-RNTI). The terminal can obtain the TC-RNTI through the pre-received random access response (Msg2). If the terminal successfully detects the DCI indicating retransmission, it can retransmit the Msg3 PUSCH based on the information included in the DCI. The information included in the DCI may be frequency hopping flag, TDRA information, FDRA information, MCS information, TPC information, channel access-CPext information, new data indicator (NDI) information, redundancy version (RV) information, HARQ process number (HPN) information, padding bit information, and UL / SUL indicator information. The Msg3 PUSCH indicated by the DCI as DCI format 0_0 can be a retransmission PUSCH.

[0185] In other words, the Msg3 PUSCH described in this disclosure can be either an initial transmission PUSCH or a retransmission PUSCH. Specifically, the PUSCH indicated by the uplink clearance of the random access response (Msg2) can be associated with the initial transmission, and the PUSCH indicated by the DCI as DCI format 0_0 scrambled by TC-RNTI can be associated with the retransmission.

[0186] Traditional transmissions of the initial PUSCH and retransmissions of the PUSCH are possible only within a single time slot. A time slot can be indicated by the TDRA field of the uplink-granted PUSCH or by the TDRA field of the DCI as DCI format 0_0. In other words, retransmission of Msg3PUSCH is not possible. Therefore, if the terminal fails to receive the scheduled Msg4 PDCCH from the base station within a specific timeframe configured after sending Msg3 PUSCH, the terminal needs to determine that the random access procedure has failed and restart it from its inception. For example, if the channel environment is poor, the base station may be unable to receive Msg3 PUSCH even if the terminal has already sent it. Therefore, the base station cannot send the scheduled Msg4 PDCCH to the terminal and needs to restart the random access procedure. That is, the coverage of Msg3 PUSCH may be low. Therefore, the entire random access procedure may be delayed. Therefore, this disclosure describes a method for solving the Msg3PUSCH coverage problem by retransmitting Msg3 PUSCH.

[0187] The base station can configure whether repeated transmission of Msg3 PUSCH is possible during random access for the terminal. For example, the base station can configure whether repeated transmission of Msg3 PUSCH is possible for the terminal through System Information Block 1 (SIB1) sent from the base station during initial cell access (Initial Access). That is, the terminal can identify whether repeated transmission of Msg3 PUSCH is possible or impossible through SIB1. Whether to repeatedly transmit Msg3 PUSCH can be configured through different SIBs other than SIB1. That is, whether repeated transmission of Msg3 PUSCH is possible can be configured through SIBx (x = 1, 2, 3...). In addition, different channels can be used to indicate whether repeated transmission of Msg3 PUSCH is possible. For example, the base station can configure whether repeated transmission of Msg3 PUSCH is possible through PBCH. Specifically, whether to repeatedly transmit Msg3 PUSCH can be configured through some bits of PBCH, or whether repeated transmission of Msg3 PUSCH is possible can be inferred from the CRC or DMRS sequence of PBCH.

[0188] Whether repeated transmission of Msg3PUSCH is possible can be explicitly indicated or inferred from the different information included in SIB1. For example, if SIB1 includes parameters for repeated transmission of Msg3PUSCH, the terminal can determine that repeated transmission of Msg3PUSCH is possible without a separate configuration (indication) for whether repeated transmission of Msg3PUSCH is possible. Conversely, if SIB1 does not include parameters for repeated transmission of Msg3PUSCH, the terminal can determine that repeated transmission of Msg3PUSCH is impossible without a separate configuration (indication) for whether repeated transmission of Msg3PUSCH is possible. Parameters for repeated transmission of Msg3PUSCH can indicate the PRACH resources for performing repeated transmission of Msg3PUSCH, and the number of times Msg3PUSCH is repeated. For example, if PRACH resources are configured for the terminal via SIB1, the terminal can repeatedly transmit Msg3PUSCH using the configured PRACH resources. Additionally, if a Msg3 PUSCH retransmission count is configured for the terminal via SIB1, the terminal can transmit Msg3 PUSCH using the configured retransmission count. The base station can configure a single value or multiple values ​​for the terminal as the possible number of retransmissions of Msg3 PUSCH. For example, the base station can configure the terminal with one or a set of values ​​including 1, 2, 4, and 8 (e.g., {1,2,4,8}). That is, the base station can configure a single value for the terminal as the Msg3 PUSCH retransmission count, or multiple values ​​that can be used as the retransmission count. In the case of configuring multiple values, the base station can indicate one of the values ​​to the terminal via additional signaling (configuration). When retransmitting Msg3 PUSCH sent by the terminal, Msg3 PUSCH can be retransmitted on a time slot basis. For example, if the Msg3 PUSCH retransmission count is 4, Msg3 PUSCH can be retransmitted on four time slots. That is, this means that Msg3 PUSCH transmitted in one time slot can be repeated four times.

[0189] When Msg3 PUSCH is configured for repeatable transmission via SIB1, a method for the terminal to determine whether to actually perform repeated transmission of Msg3 PUSCH will be described. Furthermore, the interpretation of the terminal described in this specification may have the same meaning as the meaning of the base station's configuration of the terminal. Additionally, the meaning of the configuration described in this specification may have the same meaning as the indication.

[0190] Method for the terminal to determine whether to resend Msg3 PUSCH

[0191] When the base station configures the terminal to enable repeated transmission of Msg3 PUSCH in the cell, the terminal can recognize that it always repeatedly sends Msg3 PUSCH even without additional signaling (configuration) from the base station indicating the actual repeated transmission of Msg3 PUSCH.

[0192] The terminal can determine whether to retransmit Msg3PUSCH by receiving explicit information from the base station. The explicit information that enables the terminal to determine whether to retransmit Msg3PUSCH can be as follows.

[0193] ia) Information configured from higher layers: The terminal can determine whether to repeatedly transmit Msg3 PUSCH by interpreting information configured from higher layers. For example, the base station can configure the terminal via SIB1 during the initial cell access process whether to enable repeated transmission of Msg3 PUSCH in the corresponding cell. Furthermore, if the base station is configured to enable repeated transmission of Msg3 PUSCH, the base station can configure the terminal to always repeatedly transmit Msg3 PUSCH.

[0194] ib) Information in the downlink channel for scheduling Msg3 PUSCH: The terminal can determine whether to retransmit Msg3 PUSCH by interpreting the information in the downlink channel for scheduling Msg3 PUSCH. The downlink channel may include the uplink grant of the random access response, the DCI in DCI format 1_0 as the scheduling random access response, or the DCI in DCI format 0_0 as the scheduling Msg3 PUSCH. Specifically, the terminal can determine whether to retransmit Msg3 PUSCH by interpreting the field information in the uplink grant of the random access response for the initial transmission of Msg3 PUSCH. The terminal can determine whether to retransmit Msg3 PUSCH by interpreting the field information in the DCI, which is a DCI format 0_0 scrambled by TC-RNTI, which schedules the retransmission of Msg3 PUSCH. The terminal can determine whether to retransmit Msg3 PUSCH by interpreting the field information in the DCI in DCI format 1_0 as the scheduling random access response. One bit included in the information in each downlink channel (i.e., uplink permission, DCI as DCI format 1_0 and DCI as DCI format 0_0) can be used to indicate whether Msg3 PUSCH is retransmitted, and the terminal can determine whether to retransmit Msg3 PUSCH based on the PUSCH indicating whether it is retransmitted by that one bit.

[0195] ii) The terminal can determine whether to retransmit Msg3 PUSCH by using implicit information sent by the base station. The implicit information that enables the terminal to determine whether to retransmit Msg3 PUSCH can be as follows.

[0196] A terminal can determine whether to retransmit Msg3 PUSCH by reinterpreting information in the downlink channel that schedules Msg3 PUSCH. For example, ii-a) the terminal can determine whether to retransmit Msg3 PUSCH by reinterpreting the field information in the uplink clearance of the initial transmission of Msg3 PUSCH. ii-b) the terminal can determine whether to retransmit Msg3 PUSCH by reinterpreting the field information in the DCI of the retransmission of Msg3 PUSCH, where the DCI is a DCI format 0_0 scrambled by TC-RNTI. The fields in ii-a) and ii-b) can be one of the TDRA, FDRA, MCS, and TPC fields. The method for interpreting the fields can be as follows.

[0197] The terminal can determine whether to reinterpret the TDRA field based on the number of symbols scheduled by the field. For example, if the number of symbols scheduled by the TDRA field is a specific number or greater, the terminal can determine whether to retransmit the Msg3 PUSCH by reinterpreting the field information in the uplink grant of the random access response. The base station allocates a large number of symbols to terminals lacking coverage. Therefore, if the number of allocated symbols is a pre-configured specific number or greater, the terminal can retransmit the Msg3 PUSCH to resolve the coverage issue. That is, if the number of allocated symbols is less than the pre-configured specific number, the terminal can choose not to retransmit the Msg3 PUSCH. As another example, if the number of symbols scheduled by the TDRA field is a specific number or less, the terminal can determine whether to retransmit the Msg3 PUSCH by reinterpreting the field information in the uplink grant of the random access response. This is because allocating a small number of symbols to the terminal by the base station may result in a lack of coverage. That is, if the base station allocates a specific number or greater of symbols, the terminal can choose not to retransmit the Msg3 PUSCH. The specific number can be configured from a higher layer. The higher layer can instruct SIB1 or other SIBs.

[0198] A terminal can determine whether to retransmit the Msg3 PUSCH based on the number of PRBs scheduled by the FDRA field by reinterpreting the FDRA field. For example, if the number of PRBs indicated by the FDRA field is a specific number or greater, the terminal can determine whether to retransmit the Msg3 PUSCH by reinterpreting the field information in the uplink grant of the random access response. The base station allocates a large number of PRBs to terminals lacking coverage. Therefore, if the number of allocated PRBs is a pre-configured specific number or greater, the terminal can retransmit the Msg3 PUSCH to resolve the coverage issue. That is, if the number of allocated PRBs is less than the pre-configured specific number, the terminal may not perform duplicate transmission of the Msg PUSCH. As another example, if the number of PRBs indicated by the FDRA field is a specific number or less, the terminal can determine whether to retransmit the Msg3 PUSCH by reinterpreting the field information in the uplink grant of the random access response. This is because allocating a small number of PRBs to the terminal by the base station may lead to coverage problems. In other words, if the base station allocates a specific number or more PRBs to the terminal, the terminal may not need to perform repeated transmissions of Msg3PUSCH. This specific number can be configured from a higher layer. The higher layer can specify SIB1 or other SIBs.

[0199] A terminal can determine whether to transmit Msg3 PUSCH by reinterpreting the modulation scheme or coding rate indicated by the MCS field. For example, if the modulation scheme (e.g., QPSK) or coding rate indicated by the MCS field is low, the terminal can determine whether to repeatedly transmit Msg3 PUSCH by reinterpreting the field information in the uplink grant of the random access response. The base station configures low modulation schemes or low coding rates for terminals lacking coverage. Therefore, if the modulation scheme or coding rate is low, the terminal can perform repeated transmission of Msg3 PUSCH.

[0200] Tables 4 and 5 show the modulation schemes and coding rates that can be configured for the terminal. The modulation order in Tables 4 and 5 refers to the modulation scheme. If the modulation order is q, the modulation scheme can be pi / 2-BPSK (q=1) or QPSK (q=2); if the modulation order is 2, the modulation scheme can be QPSK; if the modulation order is 4, the modulation scheme can be 16QAM; if the modulation order is 6, the modulation scheme can be 64QAM; and if the modulation order is 8, the modulation scheme can be 256QAM.

[0201] [Table 4]

[0202]

[0203] [Table 5]

[0204]

[0205] If the transform precoding for PUSCH transmissions used by the terminal is configured to be disabled, Table 4 can be applied; if the transform precoding for PUSCH transmissions used by the terminal is configured to be enabled, Table 5 can be applied. In the initial transmission of Msg3PUSCH scheduled to the terminal (i.e., the transmission of Msg3 PUSCH is configured via uplink clearance in the random access response), the base station can configure the first 16 MCS indices (0-15) in Tables 4 and / or 5. For example, referring to Table 4, the base station can configure QPSK, 16QAM, and 64QAM as modulation schemes for the terminal, and referring to Table 5, the base station can configure pi / 2-BPSK, QPSK, 16QAM, and 64QAM as modulation schemes for the terminal. Regarding the modulation scheme, the low-modulation scheme can be pi / 2-BPSK or QPSK. That is, when pi / 2-BPSK or QPSK is configured for the terminal, the terminal can repeatedly transmit Msg3 PUSCH.

[0206] A terminal can determine whether to retransmit Msg3 PUSCH based on the TPC command indicated by the field by reinterpreting the TPC field. For example, if the TPC command indicated by the TPC field specifies a certain value or greater, the terminal can determine whether to retransmit Msg3 PUSCH by reinterpreting the field information in the uplink clearance of the random access response. The base station can instruct a TPC command with a high value (the specific value or greater) to perform transmission to terminals lacking coverage using high power. Therefore, if the terminal receives a TPC command with a specific value or greater, the terminal can retransmit Msg3PUSCH. That is, if the base station configures a TPC command to the terminal with a value less than the specific value, the terminal can choose not to retransmit Msg3PUSCH.

[0207] A terminal can determine whether to retransmit the Msg3 PUSCH based on the TB size by reinterpreting specific fields. The terminal can determine the TB size of the Msg3 PUSCH based on the FDRA, TDRA, and MCS fields, and can determine whether to retransmit the Msg3 PUSCH based on the TB size. For example, if the TB size is a specific value or smaller, the terminal can determine whether to retransmit the Msg3 PUSCH by reinterpreting the field information in the uplink grant of the random access response. The base station allocates TBs with small sizes (e.g., a specific value or smaller) to terminals lacking coverage. Therefore, if a TB with a specific value or smaller is allocated to a terminal, the terminal can retransmit the Msg3 PUSCH. That is, if a TB with a specific value or larger is allocated, the terminal can choose not to perform repeated transmission of the Msg3 PUSCH.

[0208] The following section describes a method for determining the retransmission count of Msg3 PUSCH by the terminal.

[0209] Method for determining the retransmission count of Msg3 PUSCH

[0210] The terminal can determine the retransmission count of Msg3 PUSCH based on the retransmission count configured by the base station. The terminal can retransmit Msg3PUSCH according to the configured retransmission count. The base station can configure multiple retransmission count candidates for the terminal before indicating the retransmission count. Retransmission count candidates can be predetermined values, configured via broadcast information, or configured at a higher layer. For example, retransmission count candidates such as {N1, N2, N3, N4...} can be configured. Retransmission count candidates {N1, N2, N3, N4...} are natural numbers equal to or greater than 1 and can be powers of 2. For example, multiple retransmission count candidates could be {1, 2, 4, 8}. The terminal can retransmit Msg3 PUSCH as many times as one of the values ​​1, 2, 4, and 8 indicated by the base station.

[0211] i) The Msg3 PUSCH retransmission count can be configured for the terminal from a higher layer. For example, if an integer value n is configured for the terminal as the Msg3 PUSCH retransmission count from a higher layer, the terminal can repeat the Msg3 PUSCH transmission n times.

[0212] ii) The base station can configure the Msg3 PUSCH retransmission count for the terminal by using a field of the DCI format 0_0 as the DCI for scheduling the Msg3 PUSCH or the DCI format 1_0 as the DCI for scheduling the random access response (Msg2). For example, the terminal can interpret a specific number of bits in the DCI as bits indicating the Msg3 PUSCH retransmission count and can perform retransmission of the Msg3 PUSCH, wherein the DCI is scrambled by RA-RNTI and the DCI format 1_0 is used to schedule the random access response. As another example, the terminal can interpret a specific number of bits in the DCI as bits indicating the Msg3 PUSCH retransmission count and can perform retransmission of the Msg3 PUSCH, wherein the DCI is scrambled by TC-RNTI and the retransmission of the Msg3 PUSCH is scheduled.

[0213] The repeat transmission count from i) a higher layer or by ii) as a DCI indication of DCI format 0_0 or 1_0 can be one of several repeat transmission count candidates. Subsequently, the terminal can repeat the Msg3 PUSCH transmission as many times as one indication value.

[0214] According to ii) above, the fields in the DCI format 0_0 scrambled by TC-RNTI, including a specific number of bits, can be the New Data Indicator (NDI), HARQ Process Number (HPN), CSI Request, FDRA, and TPC fields. The NDI, HPN, and CSI Request fields may not be used for the transmission of Msg3 PUSCH. Therefore, the terminal can interpret the values ​​of the NDI, HPN, and CSI Request fields as field values ​​for repeated transmissions of Msg3 PUSCH.

[0215] Base stations can schedule a small number of PRBs in the frequency domain for terminals lacking coverage, or schedule PUSCHs using the highest possible transmission power. Therefore, a terminal can interpret a specific number of bits in the FDRA field as field values ​​for repeated transmissions of the Msg3 PUSCH, or it can interpret a portion of the index indicating a low dB value in the TPC field as field values ​​for repeated transmissions of the Msg3 PUSCH.

[0216] The following describes a method for the terminal to interpret a specific number of bits in the DCI for repeated transmissions of Msg3PUSCH, the DCI being a DCI format 0_0 scrambled by TC-RNTI. In the following description, the repeated transmission count candidates for Msg PUSCH configured for the terminal can be {N1, N2, N3, N4}.

[0217] The terminal can interpret the bit value of one of the fields in the DCI format 0_0 scrambled by TC_RNTI as the retransmission count for Msg3 PUSCH. That is, the terminal can interpret X bits of one of the fields NDI, HPN, CSI Request, FDRA, and TPC as the field value for retransmission of Msg3 PUSCH. For example, the terminal can interpret X (e.g., 2) bits of the HPN field as the field value for retransmission of Msg3 PUSCH. The base station can indicate one of the four retransmission counts (N1, N2, N3, and N4) using two bits. For example, {00} = N1, {01} = N2, {10} = N3, and {11} = N4 can be configured.

[0218] The terminal can interpret a combination of bit values ​​from two different fields within the DCI field of DCI format 0_0 scrambled by TC_RNTI as a retransmission count for Msg3 PUSCH. That is, the terminal can interpret X bits from one of the NDI, HPN, CSI Request, FDRA, and TPC fields, and Y bits from one of the fields that does not include those X bits, as a field value for retransmission of Msg3 PUSCH. For example, the terminal can interpret a combination of X (e.g., 1) bits from the NDI field and Y (e.g., 1) bits from the HPN field as a field value for retransmission of Msg3 PUSCH; this combination is two bits. The base station can use two bits to indicate one of the four retransmission count candidates. For example, {NDI,HPN} can be used to configure {0,0}=N1, {0,1}=N2, {1,0}=N3, and {1,1}=N4. Alternatively, {HPN,NDI} can be used to configure {0,0}=N1, {0,1}=N2, {1,0}=N3, and {1,1}=N4. As another example, a terminal can interpret a combination of X (e.g., 1) bits of the NDI field and Y (e.g., 1) bits of the CSI request field as a field value for retransmission of the Msg3 PUSCH, which is a two-bit combination. If the retransmission count candidate for the Msg3 PUSCH configured for the terminal is {N1,N2,N3,N4}, the base station can indicate one of the four retransmission count candidates using two bits. For example, {NDI,CSI request} can be used to configure {0,0}=N1, {0,1}=N2, {1,0}=N3, and {1,1}=N4. Alternatively, {CSI request, NDI} can be used to configure {0,0}=N1, {0,1}=N2, {1,0}=N3, and {1,1}=N4.

[0219] The terminal can interpret bit values ​​from two different fields within the DCI format 0_0 scrambled by TC_RNTI as field values ​​for repeated transmissions of Msg3 PUSCH. Specifically, the terminal can interpret X bits from one field of the DCI and Y bits from a field different from the field containing X bits as field values ​​for repeated transmissions of Msg3 PUSCH. For example, X bits can indicate whether the terminal interprets Y bits as field values ​​for repeated transmissions of Msg3 PUSCH, and Y bits can indicate the Msg3 PUSCH repeated transmission count. For example, one bit from the NDI field can indicate whether the terminal interprets Y bits from the FDRA field as field values ​​for repeated transmissions of Msg3 PUSCH. If one bit of the NDI field is "0", then Y bits of the FDRA field may not be interpreted as field values ​​for repeated transmissions of Msg3 PUSCH, and if one bit of the NDI field is "1", then Y bits of the FDRA field may be interpreted as field values ​​for repeated transmissions of Msg3 PUSCH. These Y bits can indicate one of the repeated transmission count candidates for Msg3 PUSCH pre-configured for the terminal. For example, if one bit of the NDI field is "1", then Y (e.g., 2) bits of the FDRA field can indicate one of four repeated transmission count candidates. Specifically, {FDRA} can be used to configure {00} = N1, {01} = N2, {10} = N3, and {11} = N4. As another example, one bit of the CSI Request field can indicate whether the terminal wants to interpret Y bits of the HPN field as field values ​​for repeated transmissions of Msg3 PUSCH. If one bit of the CSI Request field is "0", then Y bits of the HPN field may not be interpreted as field values ​​for repeat transmissions of Msg3 PUSCH, and if one bit of the CSI Request field is "1", then Y bits of the HPN field may be interpreted as field values ​​for repeat transmissions of Msg3 PUSCH. If one bit of the CSI Request field is "1", then Y (e.g., 2) bits of the HPN field may indicate one of four repeat transmission counts. Specifically, {HPN} can be used to configure {00} = N1, {01} = N2, {10} = N3, and {11} = N4.

[0220] iii) The retransmission count of Msg3 PUSCH can be indicated to the terminal via a specific field of the uplink grant in the random access response for the initial transmission of Msg3 PUSCH. The terminal can retransmit Msg3 PUSCH according to the indicated retransmission count. The terminal can interpret the bit values ​​of the specific field of the uplink grant as field values ​​for retransmission of Msg3 PUSCH. The specific bits of the uplink grant can indicate one of multiple retransmission counts for Msg3 PUSCH. The specific field of the uplink grant can be a CSI request, FDRA, TPC, or MCS field. The CSI request field may not be used for transmission of Msg3 PUSCH. Therefore, the terminal can interpret the value of the CSI request field as a field value for retransmission of Msg3 PUSCH. For example, the base station can schedule a smaller number of PRBs in the frequency domain to a terminal lacking coverage. Therefore, the terminal can interpret the bit values ​​of the FDRA field as a field value for retransmission of Msg3 PUSCH. As another example, the base station can schedule a terminal lacking coverage to transmit PUSCH using the highest possible transmission power. Therefore, a terminal can interpret a portion of the index indicating the low dB value of the TPC field as a field value for repeated transmission of Msg3PUSCH. The TPC field can be 3 bits in size, and the TPC value indicated by each code point is shown in Table 6. As another example, terminals lacking coverage can be scheduled to transmit PUSCH at the lowest possible modulation scheme (e.g., QPSK) and / or coding rate. Therefore, a terminal can interpret a portion of the low indexes from the first 16 indices (0-15) in Tables 4 and 5 included in the MCS field as a field for repeated transmission of Msg3PUSCH.

[0221] [Table 6]

[0222]

[0223]

[0224] The following section will further describe a method for interpreting a specific number of bits in the uplink clearance of a random access response. The candidate for the repeat transmission count of the Msg PUSCH configured for the terminal can be {N1, N2, N3, N4}.

[0225] The bit value of one field in the uplink permission field can be configured to indicate the retransmission count of Msg3 PUSCH. That is, the terminal can interpret the value of X bits of a specific field in the CSI request, FDRA, TPC, and MCS fields as the field value for retransmission of Msg3PUSCH.

[0226] For example, a base station can configure X (e.g., 2) bits of the FDRA field as a field for repeated transmissions of Msg3 PUSCH, and the base station can use X (e.g., 2) bits to indicate one of four (N1, N2, N3, and N4) repeated transmission counts. If the bit value of the FDRA field is "00", the terminal can determine N1, and if the bit value of the FDRA field is "01", the terminal can determine N2. If the FDRA field is "10", the terminal can determine N3, and if the FDRA field is "11", the terminal can determine N4. When the number of repeated transmission count candidates configured in a higher layer is M, the X bits of the FDRA field can be determined by X = ceil(log2(M)). The function ceil(x) in this specification is a function that gives the smallest integer equal to or greater than x. The X bits can be X bits starting from the most significant bit (MSB), excluding the bits indicating frequency hopping in the FDRA field. Specifically, if the number of RBs included in the initial uplink (UL) BWP is less than 50, then the X bits can be X bits starting from the second bit in the FDRA field, and if the number of RBs is equal to or greater than 50, then the X bits can be X bits starting from the third bit in the FDRA field.

[0227] For example, a base station can configure X (e.g., 2) bits of the TPC field as bits for a field used for repetition transmission of Msg3 PUSCH, and the base station can indicate one of four repetition counts by using two bits of the TPC field. If the bit value of the TPC field is "00", the terminal can determine N1; if the bit value of the TPC field is "01", the terminal can determine N2; if the bit value of the TPC field is "10", the terminal can determine N3; and if the bit value of the TPC field is "11", the terminal can determine "N4". When the number of repetition count candidates configured in a higher layer is M, the X bits of the TPC field can be determined by X = ceil(log2(M)). The X bits can be either the most significant X bits (MSB) or the least significant X bits (LSB) in a TPC field of size 3 bits.

[0228] For example, the base station may configure X (e.g., 2) bits of the MSC field as the bits of the field for the repeated transmission of Msg3 PUSCH, and the base station may indicate one of four repeated transmission counts by using two bits of the MSC field. If the bit value of the MSC field is "00", the terminal may determine N1; if the bit value of the MSC field is "01", the terminal may determine N2; if the bit value of the MSC field is "10", the terminal may determine N3; and if the bit value of the MSC field is "11", the terminal may determine "N4". When the number of repeated transmission count candidates configured in the higher layer is M, X bits of the MCS field can be determined by X = ceil(log2(M)). The X bits may be the most significant X bits (MSB) or the least significant X bits (LSB) in the MCS field with a size of 4 bits.

[0229] The terminal may interpret the repeated transmission count of Msg3 PUSCH by combining the bit values of two different fields among the fields of the uplink grant in the random access response. If the number of bits required to configure the repeated transmission count of Msg3 PUSCH is Z, the terminal may interpret the Z bits obtained by combining the bits of two different fields as the repeated transmission count of Msg3 PUSCH. The terminal may interpret X bits of the first field and Y bits of the second field among the CSI request, FDRA, TPC, and MCS fields as the bits for the repeated transmission of Msg3 PUSCH. The first field and the second field are different fields, and X plus Y equals Z (X + Y = Z). Additionally, X is less than Z (X < Z), Y is less than Z (Y < Z), and Z is at least two bits. If the X = Z bits of the first field can be interpreted by the terminal as the repeated transmission count of Msg3 PUSCH, the X bits of the first field may be used to indicate the repeated transmission count of Msg3 PUSCH.

[0230] If the number of duplicate transmission count candidates for Msg3 PUSCH is M (e.g., 4) ({N1, N2, N3, N4}), then Z bits are needed to indicate the duplicate transmission count to the terminal. Here, Z can be Z = ceil(log2(M)) bits. If M is 4, then Z equals 2. For example, X (e.g., 1) bits of the first field (e.g., the CSI request field) and Y (e.g., 1) bits of the second field (e.g., the FDRA field or the MCS field) can be interpreted as bits for duplicate transmissions of Msg3 PUSCH, and the base station can indicate one of the four duplicate transmission counts by using these two bits. If the value of one bit in the first field and the value of one bit in the second field are {0,0}, the repeat transmission count can be configured as N1; if the value of one bit in the first field and the value of one bit in the second field are {0,1}, then N2 can be configured; if the value of one bit in the first field and the value of one bit in the second field are {1,0}, then N3 can be configured; and if the value of one bit in the first field and the value of one bit in the second field are {1,1}, then N4 can be configured.

[0231] In addition to the embodiments described above, the uplink grant in the random access response, or the field in the DCI format 0_0 scrambled by TC-RNTI for repeated transmission of Msg3 PUSCH, can be at least one of the TDRA, FDRA, MCS, and TPC fields. The terminal can reinterpret the bit values ​​of one or more fields to perform repeated transmission of Msg3 PUSCH. The detailed method for interpreting the bit values ​​of the fields will be further described below. The repeated transmission count candidates for Msg PUSCH configured for the terminal can be {N1, N2, N3, N4}.

[0232] The terminal may repeatedly transmit Msg3 PUSCH based on the number of symbols scheduled (allocated) by the TDRA field. For example, if the number of symbols allocated for transmitting Msg3 PUSCH is from 1 to (M1 - 1), the terminal may determine N1 as the repeat transmission count; if the number of symbols allocated for transmitting Msg3 PUSCH is from M1 to (M2 - 1), N2 may be determined as the repeat transmission count; if the number of symbols allocated for transmitting Msg3 PUSCH is from M2 to (M3 - 1), N3 may be determined as the repeat transmission count; and if the number of symbols allocated for transmitting Msg3 PUSCH is from M3 to (M4 - 1), N4 may be determined as the repeat transmission count. Here, M1 < M2 < M3 < M4 and N1 > N2 > N3 > N4 can be satisfied. This is because in the case where the base station allocates a small number of symbols to the terminal, the lack of coverage may be deepened. That is, when a small number of symbols are allocated, the terminal can repeat the transmission of Msg3 PUSCH more times. As another example, N1 < N2 < N3 < N4 can be satisfied. This is because the base station may allocate a large number of symbols to the terminal lacking coverage. That is, when the base station allocates many symbols, the terminal can repeat the transmission of Msg3 PUSCH more times. The number of allocated symbols can be configured from a higher layer, specifically, through SIB1 or other SIBs.

[0233] The terminal may repeatedly transmit Msg3 PUSCH based on the number of PRBs scheduled by the FDRA field. For example, if the number of PRBs allocated for PUSCH transmission is from 1 to (M1 - 1), the terminal may determine N1 as the repeat transmission count; if the number of PRBs allocated for PUSCH transmission is from M1 to (M2 - 1), N2 may be determined as the repeat transmission count; if the number of PRBs allocated for PUSCH transmission is from M2 to (M3 - 1), N3 may be determined as the repeat transmission count; and if the number of PRBs allocated for PUSCH transmission is from M3 to (M4 - 1), N4 may be determined as the repeat transmission count. M1 < M2 < M3 < M4 and N1 > N2 > N3 > N4 can be satisfied. This is because in the case where the base station has allocated a small number of PRBs to the terminal, the lack of coverage may be deepened. That is, when a small number of PRBs are allocated, the terminal can repeat the transmission of Msg3 PUSCH more times. As another example, N1 < N2 < N3 < N4 can be satisfied. This is because the base station can allocate a large number of PRBs to the terminal lacking coverage. That is, when the base station allocates many PRBs, the terminal can repeat the transmission of Msg3 PUSCH more times. The number of allocated PRBs can be configured from a higher layer, specifically, through SIB1 or other SIBs.

[0234] The terminal may repeatedly transmit the Msg3 PUSCH based on the modulation scheme or coding rate indicated by the MCS field. For example, if the index in the MCS table indicated by the MCS field is from 0 to (M1 - 1), the terminal may determine N1 as the retransmission count; if the index in the MCS table indicated by the MCS field is from M1 to (M2 - 1), N2 may be determined as the retransmission count; if the index in the MCS table indicated by the MCS field is from M2 to (M3 - 1), N3 may be determined as the retransmission count; and if the index in the MCS table indicated by the MCS field is from M3 to (M4 - 1), N4 may be determined as the retransmission count. It can satisfy M1 < M2 < M3 < M4 and N1 > N2 > N3 > N4. This is because the base station may configure a low modulation scheme or low coding rate for the terminal lacking coverage. That is, the lower the modulation scheme or coding rate is configured, the more times the terminal can repeat the transmission of the Msg3 PUSCH.

[0235] The terminal may repeatedly transmit the Msg3 PUSCH based on the TPC command indicated by the TPC field. For example, if the TPC command index indicated by the TPC field is from 0 to (M1 - 1), the terminal may determine N1 as the retransmission count; if the TPC command index indicated by the TPC field is from M1 to (M2 - 1), N2 may be determined as the retransmission count; if the TPC command index indicated by the TPC field is from M2 to (M3 - 1), N3 may be determined as the retransmission count; and if the TPC command index indicated by the TPC field is from M3 to (M4 - 1), N4 may be determined as the retransmission count. It can satisfy M1 < M2 < M3 < M4 and N1 > N2 > N3 > N4. This is because the base station may configure a TPC command with a high value to perform the transmission to the terminal lacking coverage using high power. That is, the higher the TPC command value is configured, the more times the terminal can repeat the transmission of the Msg3 PUSCH.

[0236] The terminal can retransmit the Msg3 PUSCH based on the TB size. For example, the terminal can determine the size of the TB for transmitting the Msg3 PUSCH based on the FDRA, TDRA, and / or MCS fields. If the determined TB size is from 0 to (M1 - 1), the terminal can determine N1 as the retransmission count. If the determined TB size is from M1 to (M2 - 1), N2 can be determined as the retransmission count. If the determined TB size is from M2 to (M3 - 1), N3 can be determined as the retransmission count. And if the determined TB size is from M3 to (M4 - 1), N4 can be determined as the retransmission count. It can satisfy M1 < M2 < M3 < M4 and N1 > N2 > N3 > N4. This is because the base station can configure a small TB size for terminals with poor coverage. That is, the smaller the TB size is configured, the more times the terminal can retransmit the Msg3 PUSCH.

[0237] iv) The base station can configure a TDRA table including the retransmission count of the Msg3 PUSCH for the terminal. Each entry in the TDRA table can include the time-domain resource information of the Msg3 PUSCH and the information about the retransmission count. Additionally, each entry can include the same retransmission count or different retransmission counts. The terminal can determine the retransmission count of the Msg3 PUSCH by referring to the TDRA table. For example, when the terminal is configured to retransmit the Msg3 PUSCH, the terminal can retransmit the Msg3 PUSCH by referring to the TDRA table. On the other hand, when the terminal is configured not to retransmit the Msg3 PUSCH, the terminal can refer to the conventional TDRA table to transmit the Msg3 PUSCH. The conventional TDRA table can indicate a table that does not include the retransmission count of the Msg3 PUSCH.

[0238] One or more retransmission counts described in this specification can be values commonly used for the initial transmission and retransmission of the Msg3 PUSCH, or values used independently. When the base station indicates the retransmission of the Msg3 PUSCH, the terminal can determine the retransmission count for the retransmission of the Msg3 PUSCH based on the retransmission count indicated for the initial transmission of the Msg3 PUSCH.

[0239] The terminal can determine the retransmission count for the retransmission of the Msg3 PUSCH based on the bits of a specific field of the DCI sent by the base station, or determine the retransmission count for the retransmission of the Msg3 PUSCH through the TDRA table. The DCI can be DCI format 0_0, where the CRC is scrambled by the TC-RNTI.

[0240] a) The bit values ​​can indicate that the retransmission count for the retransmission of Msg3 PUSCH is the same as the retransmission count for the initial transmission of Msg3 PUSCH. For example, if some bits are 0 or all bits are 0, the terminal can determine that the retransmission count for the retransmission of Msg3 PUSCH is the same as the retransmission count for the initial transmission of Msg3 PUSCH.

[0241] b) The retransmission count for Msg3 PUSCH can be determined based on the retransmission count for the initial transmission of Msg3 PUSCH.

[0242] One of the bit values ​​of bi)DCI can indicate that the retransmission count for Msg3 PUSCH and the initial transmission are the same.

[0243] (b-ii) One of the DCI bit values ​​can indicate that the retransmission count for the retransmission of Msg3 PUSCH is greater than the retransmission count for the initial transmission of Msg3 PUSCH. Specifically, one of the DCI bit values ​​can indicate that the retransmission count for the retransmission of Msg3 PUSCH is twice the retransmission count for the initial transmission of Msg3 PUSCH. If the retransmission count for the initial transmission of Msg3 PUSCH has reached the maximum retransmission count (or the determined retransmission count for the retransmission of Msg3 PUSCH exceeds the maximum retransmission count), the terminal can retransmit Msg3 PUSCH based on the maximum retransmission count.

[0244] (b-iii) One of the DCI bit values ​​can indicate that the retransmission count for the retransmission of Msg3 PUSCH is less than the retransmission count for the initial transmission of Msg3 PUSCH. Specifically, one of the DCI bit values ​​can indicate that the retransmission count for the retransmission of Msg3 PUSCH is half of the retransmission count for the initial transmission of Msg3 PUSCH. If the initial retransmission count of Msg3 PUSCH has reached the minimum retransmission count (e.g., the retransmission count is 1) (or the determined retransmission count for the retransmission of Msg3 PUSCH is less than the minimum retransmission count (e.g., the retransmission count is 1)), the terminal can retransmit Msg3 PUSCH based on the minimum retransmission count.

[0245] The bits of specific fields in the aforementioned DCI can be replaced by some entries in the TDRA table. For example, the retransmission count for the retransmission of Msg3 PUSCH, indicated by some entries in the TDRA table, can be the same as, greater than, or less than the retransmission count for the initial transmission of Msg3 PUSCH (e.g., more than twice the retransmission count for the initial transmission of Msg3 PUSCH), or less than the retransmission count for the initial transmission of Msg3 PUSCH (e.g., less than half the retransmission count for the initial transmission of Msg3 PUSCH).

[0246] Methods to stop repeated transmissions of Msg3 PUSCH

[0247] If a terminal is configured by the base station to repeatedly transmit Msg3 PUSCH K times, the terminal may repeatedly transmit Msg3 PUSCH K times. The repeatedly transmitted Msg3 PUSCH are identical. Therefore, if the base station has already successfully received some of the K Msg3 PUSCHs, repeated transmission of Msg3 PUSCH may not be necessary. Therefore, a method to stop repeated transmission of Msg3 PUSCH will be described below.

[0248] i) The terminal can determine whether to repeatedly transmit Msg3PUSCH based on whether it has received the PDCCH for scheduled Msg4. The terminal can detect the PDCCH for scheduled Msg4 sent from the base station after transmitting the first Msg3 PUSCH. If the terminal has already received the PDCCH for scheduled Msg4, it can recognize that the base station has successfully received the Msg3 PUSCH. Therefore, if the PDCCH for scheduled Msg4 is received, the terminal can subsequently refrain from repeating the transmission of Msg3 PUSCH and stop such repeating. The PDCCH for scheduled Msg4 may include a DCI as DCI format 1_0 scrambled by TC-RNTI.

[0249] ii) The terminal can determine whether to retransmit the Msg3 PUSCH based on whether it has received a retransmission PDCCH for the scheduled Msg3 PUSCH. The terminal can detect a retransmission PDCCH for the scheduled Msg3 PUSCH sent from the base station after transmitting the first Msg3 PUSCH. If the terminal has already received the PDCCH for the scheduled Msg3, it can receive the scheduling information for the new Msg3 PUSCH. Therefore, the terminal can stop the retransmission of the currently transmitted Msg3 PUSCH. The PDCCH for the scheduled Msg3 PUSCH may include a DCI in DCI format 0_0 scrambled by TC-RNTI.

[0250] iii) The terminal can determine whether to repeatedly transmit Msg3PUSCH based on whether it has received an uplink grant in the random access response (Msg2) for the initial transmission of Msg3PUSCH. The terminal can receive the PDCCH for the uplink grant of Msg2 and the uplink grant of Msg2 after transmitting the first Msg3PUSCH. If the terminal has already received the uplink grant of Msg2 or the PDCCH for the uplink grant of Msg2, the terminal can be configured with scheduling information for the new Msg3PUSCH. Therefore, the terminal can stop the repeated transmission of the currently transmitted Msg3PUSCH. The PDCCH for the uplink grant of Msg2 may include a DCI as DCI format 1_0 scrambled by RA-RNTI.

[0251] iv) The terminal may perform repeated transmission of Msg3 PUSCH within a specific time window, and may stop the repeated transmission of Msg3 PUSCH when the specific time window ends. In certain cases (e.g., as described in i) to iii), where the repeated transmission of Msg3 PUSCH is stopped, the repeated transmission of Msg3 PUSCH may not be performed and may be postponed to a subsequent time slot. Therefore, the repeated transmission of Msg3 PUSCH may be postponed to after a specific time. To prevent postponement, the terminal may perform repeated transmission of Msg3 PUSCH only within a specific time (time slot) starting from the first transmission of Msg3 PUSCH. That is, the terminal may perform repeated transmission of Msg3 PUSCH within a specific time (time slot), but may stop performing repeated transmission of Msg3 PUSCH when the specific time (time slot) ends.

[0252] As described above, the terminal can reinterpret the CSI Request field, FDRA field, and TPC and MCS fields to determine the duplicate transmission count of Msg3 PUSCH. The method by which the terminal determines whether to reinterpret the CSI Request field, FDRA field, and TPC field to determine the duplicate transmission count of Msg3 PUSCH will be described below.

[0253] Method for determining whether to reinterpret the field for use in Msg3PUSCH duplicate transmission count

[0254] i) When the base station configures a separate PRACH resource (e.g., a PRACH preamble or RACH timing) for the terminal to retransmit Msg3 PUSCH, and the terminal transmits PRACH to the base station on the separate PRACH resource, the terminal can reinterpret the CSI request field, FDRA field, and TPC field based on the method described above. Conversely, a terminal that has already transmitted PRACH on a resource other than a separate PRACH resource can always reinterpret the CSI request field, FDRA field, and TPC field for its original purpose. The separate PRACH resource can be configured by the base station for the terminal while being included in SIB1. That is, the terminal can retransmit Msg3 PUSCH on at least one determined resource based on the PRACH preamble and RACH timing. For example, the base station can identify on which resource the terminal transmitted PRACH. If the terminal has already transmitted PRACH on a separate PRACH resource, the base station can indicate the retransmission count of Msg3 PUSCH by using at least one or two of the CSI request field, FDRA field, and TPC field. When the base station indicates the retransmission count, it can indicate that the retransmission count is 1. In other words, Msg3PUSCH can be configured to be transmitted without duplication. One of several pre-configured duplicate transmission count candidates (e.g., N1, N2, N3, and N4) can be configured to a value of "1". Additionally, N1 is pre-arranged (not configured separately) as a value of 1, and the base station can configure only the values ​​of N2, N3, and N4.

[0255] The base station can indicate whether to repeatedly transmit Msg3 PUSCH through a specific field (e.g., the CSI request field). As mentioned above, even if the terminal transmits PRACH on resources configured separately by the base station, the base station can indicate not to perform repeated transmission of Msg3 PUSCH through a specific field. When the base station has already indicated to perform repeated transmission of Msg3 PUSCH through a specific field (e.g., the CSI request field), at least one or both fields between the FDRA field and the TPC field can be used to indicate the repeated transmission count. In this case, the base station does not need to indicate 1 as the repeated transmission count of Msg3 PUSCH. This is because the base station can indicate not to perform repeated transmission of Msg3 PUSCH through a specific field. Therefore, the values ​​of the repeated transmission count candidates (N1, N2, N3, and N4) may not include 1. That is, the repeated transmission count candidates can be configured to have values ​​greater than 1.

[0256] ii) The terminal may determine whether to reinterpret the CSI request field, FDRA field, and TPC field for the purpose of retransmitting Msg3 PUSCH based on specific fields. The specific field may be a field in the uplink clearance of the random access response. For example, the specific field may be the CSI request field, and the value of one bit in the CSI request field may be used to determine whether to perform reinterpretation. If the value of the CSI request field is 0, the terminal may interpret the FDRA field and TPC field for the original purpose (which is not for identifying whether to retransmit Msg3 PUSCH). If the value of the CSI request field is 1, the terminal may reinterpret the FDRA field and TPC field. The CSI field is used to determine whether to perform reinterpretation and is therefore excluded from the aforementioned fields for reinterpreting Msg3 PUSCH retransmission.

[0257] Method for determining transmission power command value

[0258] The terminal needs to determine the TPC command value for Msg3 PUSCH. When Msg3 PUSCH is repeatedly transmitted, the terminal can determine the highest 8dB increase in Table 6 as the Transmission Power Command (TPC) value. When the terminal repeatedly transmits Msg3 PUSCH, the base station can configure a specific value for the terminal as the TPC value.

[0259] The terminal can determine the transmission power command value based on the remaining bits after excluding the X bits used for repeated transmissions of Msg3 PUSCH. The number of remaining bits is 3-X, so the remaining bits can be one bit or two bits.

[0260] The following section describes a detailed method for determining the TPC command value based on the remaining bits.

[0261] i) If the remaining bit is one bit, the terminal can insert "11" into the two bits that constitute the MSB. Therefore, the terminal can determine the TPC value based on Table 6 and "11a" (where a is the value of the remaining bit). If the value of the remaining bit (a) is 0, it represents "110". "110" is 6, so referring to Table 6 indicates an increase of 6 dB. If the value of the remaining bit (a) is 1, it represents "111". "111" is 7, so referring to Table 6 indicates an increase of 8 dB. That is, referring to Table 6, only the two highest TPC command values ​​(6 and 7) can be indicated to the terminal.

[0262] ii) If the remaining bit is a single bit, the TPC value can be determined based on the value of that single bit. Specifically, the TPC value can be determined according to Table 7.

[0263] [Table 7]

[0264] TPC command Value (in dB) 0 TPC_0 1 TPC_1

[0265] Referring to Table 7, if the value of the remaining bit (a) is "0", the terminal can use the TPC_0 value, and if the value of the remaining bit is "1", the terminal can use the TPC_1 value. TPC_0 and TPC_1 can be predetermined values ​​or can be configured individually by the base station. The values ​​of TPC_0 and TPC_1 can be two values ​​from -6, -4, -2, 0, 2, 4, 6, and 8. The TPC_0 value can be one of the negative values ​​(or values ​​other than positive values) from -6, -4, -2, 0, 2, 4, 6, and 8, and the TPC_1 value can be one of the positive values. Additionally, to extend PUSCH coverage, the values ​​of TPC_0 and TPC_1 can be determined to be two positive values ​​(or values ​​other than negative values) from -6, -4, -2, 0, 2, 4, 6, and 8. The difference between the TPC_0 and TPC_1 values ​​can be 4 dB. Specifically, TPC_0 can be 4dB and TPC_1 can be 8dB, TPC_0 can be 2dB and TPC_1 can be 6dB, or TPC_0 can be 0dB and TPC_1 can be 4dB. The difference between the TPC_0 value and the TPC_1 value can be 8dB.

[0266] If the remaining bits are two bits, the terminal can insert a "1" into one bit of the MSB, similar to method i). Therefore, the terminal can determine the TPC value based on Table 6 and "1ab" (where ab is the value of the remaining two bits). That is, if the value of the remaining two bits (ab) is 00, it represents "100". "100" is 4, and therefore indicates an increase of 2dB. Similarly, if the value of the remaining two bits is 01, it represents "101". "101" is 5, and therefore indicates an increase of 4dB. If the value of the remaining two bits is 10, it represents "110". "110" is 6, and therefore indicates an increase of 6dB. If the value of the remaining two bits is 11, it represents "111". "111" is 7, and therefore indicates an increase of 8dB. Only the four highest TPC command values ​​(4, 5, 6, and 7) in Table 6 can be indicated to the terminal.

[0267] If there are two remaining bits, the four TPC values ​​can be determined based on the values ​​of the remaining two bits, similar to the method in ii). Specifically, the TPC values ​​can be determined according to Table 8.

[0268] [Table 8]

[0269] TPC command Value (in dB) 0 TPC_0 1 TPC_1 2 TPC_2 3 TPC_3

[0270] If the remaining two bits (ab) are "00", the terminal can use the TPC_0 value; if the remaining two bits (ab) are "01", the terminal can use the TPC_1 value; if the remaining two bits (ab) are "10", the terminal can use the TPC_2 value; and if the remaining two bits (ab) are "11", the terminal can use the TPC_3 value. TPC_0, TPC_1, TPC_2, and TPC_3 can be predetermined values ​​or values ​​configured individually by the base station. The values ​​of TPC_0, TPC_1, TPC_2, and TPC_3 can be four of the following: -6, -4, -2, 0, 2, 4, 6, and 8. The TPC_0 value can be one of the negative values ​​(or values ​​other than positive values) of -6, -4, -2, 0, 2, 4, 6, and 8, while the TPC_1, TPC_2, and TPC_3 values ​​can be positive values. Additionally, TPC_0 and TPC_1 values ​​can be negative (or any value other than positive) from -6, -4, -2, 0, 2, 4, 6, and 8, while TPC_2 and TPC_3 values ​​can be positive. Furthermore, to extend PUSCH coverage, the values ​​of TPC_0, TPC_1, TPC_2, and TPC_3 can be four positive (or any value other than negative) from -6, -4, -2, 0, 2, 4, 6, and 8. Additionally, the difference between the values ​​of TPC_0, TPC_1, TPC_2, and TPC_3 can be 4 dB. Specifically, TPC_0 can be -6 dB, TPC_1 can be -2 dB, TPC_2 can be 2 dB, and TPC_3 can be 6 dB. Moreover, TPC_0 can be -4 dB, TPC_1 can be 0 dB, TPC_2 can be 4 dB, and TPC_3 can be 8 dB.

[0271] The above description has outlined a method for a base station to perform signaling related to Msg3 PUSCH retransmission. Multiple pieces of information related to Msg3 PUSCH retransmission can be configured using some bits of a specific field of the DCI or uplink grants in a random access response. Using some bits requires adding bits, which may incur overhead. Alternatively, information related to Msg3 PUSCH retransmission can be configured by reinterpreting uplink grants or specific fields of the DCI, or by reinterpreting bits of specific fields. This reinterpretation method can limit the base station's flexible scheduling. Furthermore, the base station may not be able to discern information about whether a terminal supports Msg3 PUSCH retransmission. In this case, even if the base station configures multiple pieces of information related to Msg3 PUSCH retransmission, the terminal may fail to perform Msg3 PUSCH retransmission and misunderstand the uplink grants or DCI. To address these issues, a method will be described below for notifying the number of retransmissions or whether to perform Msg3 PUSCH retransmission when the terminal sends Msg3 PUSCH to the base station.

[0272] Method of signaling information related to repeated transmissions via Msg3PUSCH

[0273] Figure 17 This is a diagram illustrating the repeated transmission of Msg3 PUSCH according to an embodiment of the present disclosure.

[0274] refer to Figure 17 The terminal can repeatedly transmit Msg3 PUSCH on four time slots. The Msg3 PUSCH transmitted on each time slot can transmit the same TB. The same TB can be repeatedly transmitted on each time slot with the same or different Redundancy Versions (RVs). The Msg3 PUSCH transmitted on each time slot can include at least one DMRS symbol. A DMRS symbol can indicate the symbol to which the DMRS is mapped. The Msg3 PUSCH transmitted on each time slot can include multiple DMRS symbols. The earliest transmitted DMRS symbol among the multiple DMRS symbols can be referred to as the first DMRS symbol, and subsequent transmitted DMRS symbols can be referred to as supplementary DMRS symbols. In this specification, for ease of explanation, the first DMRS symbol is referred to as the DMRS symbol, but it is also obvious that supplementary DMRS symbols may be used.

[0275] The base station configures information related to the transmission of Msg3 PUSCH for the terminal (e.g., information configured via uplink permission). Therefore, the base station can know in advance the resources (time slots, symbols, PRBs, etc.) for transmitting the first Msg3 PUSCH (Msg3 PUSCH rep#1). Additionally, the base station can know in advance the location of the DMRS symbols included in Msg3 PUSCH rep#1. The base station can receive Msg3 PUSCH rep#1 transmitted by the terminal based on information related to repeated transmissions. The same TB is repeatedly transmitted in each time slot, so even when only Msg3 PUSCH rep#1 is received, the base station can decode the TB transmitted by Msg3 PUSCH rep#1. However, in poor channel conditions, even when Msg3 PUSCH rep#1 is received, the base station may not be able to decode the TB transmitted by Msg3 PUSCH rep#1. The base station can receive a second Msg3 PUSCH (Msg3 PUSCH rep#2) in the time slot immediately following the time slot in which Msg3 PUSCH rep#1 was transmitted. Specifically, the base station can determine whether Msg3 PUSCH rep#2 is received in the time slot immediately following the time slot in which Msg3 PUSCH rep#1 was transmitted, at the same symbol position and / or the same PRB as Msg3 PUSCH rep#1. The base station may not be able to identify whether the terminal has repeatedly transmitted Msg3 PUSCH. Therefore, in order to determine whether to receive Msg3 PUSCH rep#2, the base station can measure the energy of the time-frequency resources in which Msg3 PUSCH rep#2 is expected to be transmitted, and can measure the DMRS correlation in the time-frequency resources of the DMRS in which Msg3 PUSCH rep#2 is expected to be transmitted. Based on the measurement results, the base station can determine (identify) whether the terminal has transmitted Msg3 PUSCH rep#2. If the base station determines from the measurement results that Msg3 PUSCH rep#2 has been transmitted, it can combine Msg3 PUSCH#1 and Msg3 PUSCH#2 to obtain a lower code rate and is more likely to decode the TB transmitted by Msg3 PUSCH. This increases the code rate and thus the probability of decoding the TB transmitted by Msg3 PUSCH. The process of determining whether Msg3 PUSCH has been repeatedly transmitted can be repeated in time slots where there is a possibility of Msg3 PUSCH transmission. However, terminals that repeatedly transmit Msg3 PUSCH are located at the edge of the cell and therefore lack coverage. Therefore, the performance of the measurement results may be degraded. Furthermore, the base station needs to identify whether Msg3 PUSCH has been repeatedly transmitted for each time slot, which may increase complexity.

[0276] Figure 18 This is a diagram illustrating repeated transmissions of Msg3PUSCH using three DMRS according to an embodiment of this disclosure.

[0277] refer to Figure 18 There are three methods for the terminal to send Msg3 PUSCH: (a) The terminal can send Msg3 PUSCH without repetition. In other words, the terminal can send Msg3 PUSCH only in one time slot and not repetition in subsequent time slots. (b) The terminal can repeat the transmission of Msg3 PUSCH twice. This method can be applied to situations where multiple repetitions of Msg3 PUSCH are not necessary even when the uplink channel environment is poor. (c) The terminal can repeat the transmission of Msg3 PUSCH four times. Compared to method (b), this method can be applied to situations with poor uplink channel environment.

[0278] Additionally, refer to Figure 18 The terminal can use DMRS to indicate the Msg3 PUSCH transmission method (whether to retransmit) to the base station. Specifically, when the terminal transmits Msg3 PUSCH using method (a), DMRS A can be used to indicate the Msg3 PUSCH transmission method. When the terminal transmits Msg3 PUSCH using method (b), DMRS B in each of the two time slots, Msg3 PUSCHrep#1 and Msg3 PUSCHrep#2, can be used to indicate the Msg3 PUSCH transmission method. When the terminal transmits Msg3 PUSCH using method (c), DMRS C in each of the four time slots, Msg3 PUSCHrep#1, Msg3 PUSCHrep#2, Msg3 PUSCHrep#3, and Msg3 PUSCHrep#4, can be used to indicate the Msg3 PUSCH transmission method. In other words, when DMRS A is received, the base station can identify that Msg3 PUSCH has been sent once; when DMRS B is received, the base station can identify that the transmission of Msg3 PUSCH has been repeated twice; and when DMRS C is received, the base station can identify that the transmission of Msg3 PUSCH has been repeated four times.

[0279] Different basic sequences (base sequences) can be applied to DMRS A, DMRS B, and DMRS C respectively. Since different basic sequences are applied to DMRS A, DMRS B, and DMRS C respectively, the base station can determine which basic sequence has been applied by measuring the correlation between the basic sequences.

[0280] DMRS A, DMRS B, and DMRS C can have the same basic sequence, but their sequences can be initialized with different sequence initialization values ​​(sequence initialization). If the sequence of DMRS A is initialized with a first value, then the sequences of DMRS B and DMRS C can be initialized with a second and a third value, respectively. The base station can measure the correlation under the assumption that the sequences are initialized with the first, second, and third values, and can determine which sequence initialization value has been used based on the results of the correlation measurement. For example, DMRS activating the transmission of the precoded Msg3PUSCH can be as shown in Equation 1.

[0281] [Equation 1]

[0282]

[0283] In equation 1, N slot symb It can represent the number of symbols per time slot, n μ s,f The index can represent the index of a time slot in a frame with a subcarrier spacing setting μ, l can represent the index of an OFDM symbol in the time slot, and N ID nSCID It can be expressed according to n SCID The scrambling identifier for the DMRS sequence initialization value (0 or 1). Referring to Equation 1, DMRS A, DMRS B, and DMRS C can be distinguished by at least different c_init values.

[0284] DMRS A, DMRS B, and DMRS C can be transmitted through different DMRS ports. In other words, the terminal can transmit Msg3PUSCH through different DMRS ports. The base station can determine which DMRS has been used based on the DMRS port of the Msg3 PUSCH transmitted by the terminal.

[0285] The base station can determine whether the DMRS in the first time slot transmitting Msg3 PUSCH is DMRS A, DMRS B, or DMRS C, in order to identify whether Msg3 PUSCH has been transmitted repeatedly or how many times it has been transmitted. The base station can receive Msg3 PUSCH based on the result of the DMRS determination.

[0286] However, terminals with low coverage repeatedly transmit Msg3 PUSCH, making it highly unlikely that the base station will correctly determine the DMRS for Msg3 PUSCH. Therefore, the base station may determine the method for transmitting Msg3 PUSCH in the first timeslot with low accuracy using one of multiple DMRSs (DMRS A, DMRS B, and DMRS C). Therefore, a method will be described below in which the terminal indicates the Msg3 PUSCH transmission method using two DMRSs (DMRS A and DMRS B).

[0287] Figures 19 to 21 The illustration shows a Msg3 PUSCH transmission method using two DMRSs according to an embodiment of the present disclosure.

[0288] refer to Figure 19 In case (a) where Msg3 PUSCH is not retransmitted, DMRS A can be used to indicate the Msg3 PUSCH transmission method. In case (b) where Msg3 PUSCH is retransmitted twice or (c) where Msg3 PUSCH is retransmitted four times, DMRS B can be used to indicate the Msg3 PUSCH transmission method. That is, the terminal can use DMRS A or DMRS B to notify the base station whether Msg3 PUSCH has been retransmitted. The base station can use the DMRS in the first time slot of Msg3 PUSCH transmission to determine whether Msg3 PUSCH has been retransmitted. For example, if the received DMRS is determined to be DMRS A, the base station can determine that Msg3 PUSCH has not been retransmitted. Conversely, if the received DMRS is determined to be DMRS B, the base station can determine that Msg3 PUSCH has been retransmitted.

[0289] DMRS A can be the same as or different from the DMRS of a terminal that does not have the ability to retransmit Msg3 PUSCH. If the DMRS are the same, even if the DMRS on the first time slot is determined to be DMRS A, the base station cannot determine whether the terminal that has already transmitted Msg3 PUSCH is a terminal capable of retransmitting Msg3 PUSCH. Therefore, in the case of indicating a retransmission of Msg3 PUSCH, it is impossible to indicate a retransmission for the retransmission, or even when indicating a retransmission of Msg3 PUSCH, it is necessary to separately determine whether a retransmission has already been performed. If the DMRS are different (i.e., the base station receives DMRS B), the base station can determine that the terminal that has already transmitted Msg3 PUSCH is capable of retransmitting Msg3 PUSCH. Therefore, when indicating a retransmission of Msg3 PUSCH, the base station can indicate a retransmission for the retransmission.

[0290] refer to Figure 20 If Msg3 PUSCH is not transmitted in time slots following the first time slot, the terminal can transmit DMRS A in the first time slot. Conversely, if Msg3 PUSCH is repeatedly transmitted in time slots following the first time slot, the terminal can transmit DMRS B in the first time slot. In other words, DMRS A can be used if Msg3 PUSCH is not repeatedly transmitted or if the Msg3 PUSCH transmitted in the first time slot among the repeatedly transmitted Msg3 PUSCH is the last Msg3 PUSCH. For example, see reference... Figure 20 (a) The terminal does not retransmit Msg3 PUSCH, therefore DMRS A can be used. (See reference) Figure 20 (b) Msg3 PUSCH is repeatedly transmitted in both the first and second time slots, and therefore DMRSB can be transmitted in the first time slot and DMRS A can be transmitted in the second time slot. (See reference) Figure 20 (c) Msg3PUSCH can be repeatedly transmitted in the first, second, third, and fourth time slots, and therefore DMRS B can be transmitted in the first, second, and third time slots, and DMRS A can be transmitted in the fourth time slot. That is, the base station can determine for each time slot whether the DMRS included in the Msg3 PUSCH is DMRS A or DMRS B, and if the DMRS determined for the first time slot is DMRSA, the base station can determine that there is no Msg3 PUSCH to be transmitted in time slots after the first time slot. Conversely, if the DMRS determined for the first time slot is DMRS B, the base station can determine that Msg3 PUSCH is repeatedly transmitted in time slots after the first time slot. The base station can determine the DMRS for each time slot, but may not need to determine the DMRS for a specific time slot. For example, if the repetition count candidate for Msg3 PUSCH configured for the terminal is {R_1, R_2, ..., R_r}, then DMRS A can be transmitted only in slots R_1, R_2, and R_r. Therefore, the base station can identify the existence of additional transmissions of Msg3 PUSCH by determining only the DMRS in slots R_1, R_2, ..., R_r. Specifically, if the repetition count candidate for Msg3 PUSCH configured for the terminal is {1, 2, 4}, then DMRS A can be transmitted only in slots 1, 2, and 4. Therefore, in situations such as... Figure 20 In the case shown in (c) where Msg3 PUSCH is transmitted four times, the base station only needs to determine the DMRS for the first, second, and fourth time slots. That is, in Figure 20 In (c), it is not necessary to determine the DMRS for the third time slot. However, in the reference... Figure 20In the described scheme, if the base station fails to receive the Msg3PUSCH that transmits DMRS A, the base station cannot determine the time slot for terminating the transmission of Msg3PUSCH. For example, regarding Msg3PUSCH being transmitted twice, if the base station fails to receive the Msg3PUSCH that includes the DMRS transmitted in the second time slot, the base station cannot determine the time slot for terminating the transmission of Msg3PUSCH.

[0291] refer to Figure 21 A terminal can transmit Msg3 PUSCH, including DMRS A, in a specific number of consecutive time slots. The specific number is determined based on the repetition count of Msg3 PUSCH and can be predetermined. The specific number can have a value corresponding to half of the repetition count of Msg3 PUSCH. That is, if the transmission of Msg3 PUSCH is repeated twice, the specific number can be 1, and if the transmission of Msg3 PUSCH is repeated four times, the specific number can be 2. In other words, if the transmission of Msg3 PUSCH is repeated R times, the specific number can be obtained by f(R / 2). The function f(x) can give one of the values ​​obtained by rounding down, rounding to the nearest whole number, and rounding up. The specific number of consecutive time slots can be calculated starting from the time slot where the repetition of Msg3 PUSCH ends. (Reference) Figure 21 (c) The transmission of Msg3 PUSCH can be repeated four times, and Msg3 PUSCH including DMRS A can be transmitted on two consecutive time slots starting from the last time slot (i.e., the third and fourth time slots). In the adoption of Figure 21 In the method, if the base station determines that the DMRS transmitted in at least one time slot between the third and fourth time slots is identified as DMRS A, then the base station can identify that the transmission of Msg3PUSCH ends in the fourth time slot.

[0292] Reference Figures 19 to 21 In the two DMRS methods described, different DMRS can be transmitted in different time slots. However, if the base station needs to perform joint channel estimation, the transmission of the same DMRS is required. Therefore, the two DMRS method can be applied to all cases except those involving joint channel estimation.

[0293] Method of signaling information related to the repeated transmission of Msg3PUSCH via UCI bits

[0294] Figures 22 to 26 The illustration shows a method for determining the number of modulation symbols used for multiplexing uplink control information included in Msg3 PUSCH, according to an embodiment of the present disclosure.

[0295] The number of modulation symbols mapped to the Msg3 PUSCH for the transmission of uplink control information (UCI) at each layer can be calculated as shown in Equation 2. Equation 2 can also be used to calculate the number of modulation symbols when transmitting HARQ-ACK multiplexed in the PUSCH.

[0296] [Equation 2]

[0297]

[0298] In equation 2, O UCI This can indicate the number of bits used to indicate whether to perform a repeated transmission of Msg3 PUSCH, or a repeat transmission count. L UCI It can be represented as O UCI The number of CRC bits in the channel coding. β PUSCH offset This is the offset value used to determine the number of resources used to map UCI to Msg3PUSCH, and it can be configured via SIB. UL-SCH This indicates the number of code blocks (CBs) included in Msg3 PUSCH. K r This represents the size of the r-th CB included in Msg3PUSCH. UCI sc (l) represents the number of REs available for UCI transmission in the l-th symbol of Msg3 PUSCH. N PUSCH symb,all This indicates the number of all symbols used for the transmission of the Msg3 PUSCH, which includes DMRS. The scaling value can be configured via SIB. l0 represents the index of the first PUSCH symbol of DMRS that is not following the DMRS symbol. For example, when DMRS is transmitted in the l-th symbol, M... UCI sc (l) is 0, otherwise, M UCI sc (l) equals M PUSCH sc -M PT-RS sc (l). M PUSCH sc This represents the number of subcarriers scheduled for PUSCH in the frequency domain, and M... PT-RS sc (l) represents the number of subcarriers including the l-th PUSCH symbol of PTRS. The terminal can base its calculation on Q' calculated from Equation 2. UCI The modulation symbols (number of REs) are multiplexed using UCI in the PUSCH. Q' UCI The modulation symbol can be mapped to the Q' of Msg3 PUSCH. UCIOne RE. When HARQ-ACK is multiplexed in PUSCH, the mapping scheme can be the same as the HARQ-ACK mapping scheme. That is, Q' can be selected in the symbol of the DMRS symbol of the immediately following Msg3 PUSCH. UCI One RE.

[0299] Terminals that do not support repeated transmission of Msg3 PUSCH cannot send Msg3 PUSCH including UCI multiplexing. Therefore, when receiving Msg3 PUSCH, the base station needs to determine whether the UCI has already been multiplexed. For example, if the UCI bit size is less than or equal to two bits, the terminal can check the Q' in the RE of the sent Msg3 PUSCH. UCI Each RE is perforated, and in Q' UCI The UCI is transmitted in each RE. Therefore, the base station is not required to distinguish whether the UCI is multiplexed. In other words, the mapping of Msg3 PUSCH does not need to be included in the Q' of the transmitted UCI. UCI One RE change. On the other hand, for example, if the UCI bit size is greater than two bits, then Msg3PUSCH can be rate-matched and mapped to Q' in the UCI. UCI The RE is transmitted around it. The base station needs to decode Msg3PUSCH twice because the mapping of Msg3PUSCH can be changed according to different rate matches in the case of multiplexed and unmultiplexed UCI. Therefore, the UCI bit size needs to be limited to two bits or less to reduce the number of decoding operations performed by the base station.

[0300] If the UCI bit size is one bit, then i) the UCI bit can indicate that the repeat count for Msg3PUSCH is 1 or R. R can be a value configured in the SIB. The count of 1 is not configured separately, and if the value of the UCI bit is "0", it can always be determined that the repeat count is 1. ii) The UCI bit can indicate that the repeat count for Msg3PUSCH is R_1 or R_2. The values ​​of R_1 and R_2 can be configured in the SIB. The values ​​of R_1 and R_2 do not have to be 1.

[0301] If the UCI bit size is two bits, the UCI bit can indicate i) that the repeat count for Msg3PUSCH is 1, R_1, R_2, or R_3. The values ​​of R_1, R_2, and R_3 can be configured in the SIB. The count of 1 is not configured separately, and if the UCI bit is "00", it can always be determined that the repeat count is 1. ii) The UCI bit can indicate that the repeat count for Msg3PUSCH is R_1, R_2, R_3, or R_4. The values ​​of R_1, R_2, R_3, and R_4 can be configured in the SIB.

[0302] In cases where the terminal needs to indicate more various repetition counts (such as {1,2,4,8,16,32}), the UCI bit size must be greater than two bits. Therefore, a method for sending more than two bits of UCI will be described.

[0303] refer to Figure 23 The terminal can generate a sub-UCI by grouping up to two UCI bits. The terminal can transmit the sub-UCI in each of the first and second time slots. The terminal can multiplex and transmit the first sub-UCI in the Msg3 PUSCH on the first time slot, and multiplex and transmit the second sub-UCI in the Msg3 PUSCH on the second time slot. The base station can receive the first and second sub-UCIs transmitted in the first and second time slots respectively to generate the entire UCI bit set. The base station can determine the retransmission count of the Msg3 PUSCH based on the entire UCI bit set. (Reference) Figure 24 The terminal can multiplex a 1-bit UCI bit value "0" or "1" in each time slot's Msg3 PUSCH and transmit it. A UCI bit value "0" can mean that the Msg3 PUSCH is retransmitted in the time slot following the one multiplexed with UCI bit value "0". A UCI bit value "1" can mean that the time slot sending the Msg3 PUSCH with UCI bit value "1" is the last time slot for transmitting the Msg3 PUSCH. (Reference) Figure 24 (b) The terminal may multiplex the UCI bit value "0" in the Msg3 PUSCH transmitted in the first time slot. This is because the Msg3 PUSCH is retransmitted in the second time slot (the time slot following the first time slot). The terminal may also multiplex the UCI bit value "1" in the Msg3 PUSCH transmitted in the second time slot. This is because the second time slot is the last time slot for retransmitting the Msg3 PUSCH. (See reference) Figure 24 (c) The terminal may multiplex the UCI bit value "0" in the Msg3 PUSCH transmitted on each of the first, second, and third time slots. This is because the Msg3 PUSCH is retransmitted on the second time slot (the time slot following the first time slot), the third time slot (the time slot following the second time slot), and the fourth time slot (the time slot following the third time slot). The terminal may multiplex the UCI bit value "1" in the Msg3 PUSCH transmitted on the fourth time slot. This is because the fourth time slot is the last time slot for retransmitting the Msg3 PUSCH. (Refer to...) Figure 24 In the described method of multiplexing UCI bit values ​​"0" or "1", if the base station fails to receive a Msg3 PUSCH with a multiplexed UCI bit value "1", it is impossible to determine the time slot of the Msg3 PUSCH that ends the repeated transmission. For example, in Figure 24 In case (b), the retransmission count of Msg3 PUSCH is 2. If the base station fails to receive Msg3 PUSCH transmitted in the second time slot, the base station fails to recognize the UCI bit value "1" and therefore cannot determine the time slot to end the retransmission of Msg3 PUSCH.

[0304] A terminal can multiplex the UCI bit value "1" in Msg3 PUSCH transmitted over a specific number of consecutive time slots. The specific number is determined based on the repetition count of Msg3 PUSCH and can be predetermined. This specific number can be half the repetition count of Msg3 PUSCH. Specifically, if the transmission of Msg3 PUSCH is repeated twice, the specific number can be 1, and if the transmission of Msg3 PUSCH is repeated four times, the specific number can be 2. In other words, if Msg3 PUSCH is repeated R times, the specific number can be obtained by f(R / 2). The function f(x) can give one of the values ​​obtained by rounding down, rounding up, and rounding up x. A specific number of consecutive time slots can be selected starting from the time slot where the last repetition of Msg3 PUSCH was performed. Time slots can be selected starting from the last time slot where the repetition was performed. (Reference) Figure 25 (c) The transmission of Msg3 PUSCH can be repeated four times. The terminal can multiplex the UCI bit value "1" in each of the Msg3 PUSCH transmitted in two consecutive time slots (the third and fourth time slots) starting from the time slot where the last repeated transmission of Msg3 PUSCH was performed, and then transmit Msg3 PUSCH. Figure 24 (c) and Figure 25 In the comparison between (c), Figure 25 In (c), it can be noted that if the base station identifies the UCI bit value "1" multiplexed in the Msg3 PUSCH transmitted in at least one time slot between the third and fourth time slots, the base station can identify the end of the Msg3 PUSCH in the fourth time slot.

[0305] According to the method described above, UCI is multiplexed in each time slot, thus reducing the number of REs used to transmit Msg3PUSCH. Therefore, it is necessary to multiplex UCI only in as few time slots as possible. For example, the base station can determine that Msg3PUSCH with unmultiplexed UCI bit value "1" is the same as Msg3PUSCH with multiplexed UCI bit value "1". As another example, the terminal can multiplex UCI in Msg3PUSCH in each specific time slot and transmit Msg3PUSCH. For example, the terminal can make the time slots for repeatedly transmitting Msg3PUSCH into a bundle of N time slots, and multiplex UCI in the first time slot of each bundle of N time slots and transmit Msg3PUSCH. The bundle of N time slots can be called a time slot bundle. If Msg3PUSCH is repeatedly transmitted in time slot bundles after the first time slot bundle, the terminal can multiplex UCI bit value "0" in Msg3PUSCH transmitted in the (first) time slot included in the first time slot bundle. If Msg3PUSCH is not retransmitted in time slot bundles following the first time slot bundle, the terminal can multiplex the UCI bit value "1" in the Msg3 PUSCH transmitted in the (first) time slot included in the first time slot bundle. That is, the first time slot bundle can be the time slot bundle where the last Msg3 PUSCH was transmitted. (See reference) Figure 26 (b) The terminal can configure time slot bundling by bundling two time slots. The terminal can multiplex the UCI bit value "1" in the Msg3 PUSCH transmitted in the first time slot of the first time slot bundling. This is because the Msg3 PUSCH is not retransmitted in time slot bundlings following the first time slot bundling. See reference. Figure 26 (c) The terminal can configure time slot bundling by bundling two time slots. The terminal can multiplex the UCI bit value "0" in the Msg3 PUSCH transmitted in the first time slot of the first time slot bundling. This is because the Msg3 PUSCH is repeatedly transmitted in the second time slot bundling (the time slot bundling following the first time slot bundling). The terminal can also multiplex the UCI bit value "1" in the Msg3 PUSCH transmitted in the first time slot of the second time slot bundling. This is because the Msg3 PUSCH is not repeatedly transmitted in the time slot bundling following the second time slot bundling.

[0306] Method for determining the time slot for repetitive transmission of Msg3 PUSCH in TDD scenario

[0307] The base station can be configured with symbol direction for TDD operations.

[0308] The base station can configure the cell common symbol direction for terminals. The symbol direction can be configured using SIB1 sent to terminals present in the cell. The base station can configure the cell common symbol direction via the tdd-UL-DL-ConfigurationCommon of SIB1. The cell common symbol direction can be determined to correspond to one of UL symbols, DL symbols, and flexible symbols. A cell common UL symbol indicates a symbol used only in uplink transmissions. A cell common DL symbol indicates a symbol used only in downlink transmissions. A cell common flexible symbol is a symbol whose specific direction has not yet been determined and indicates a symbol that can be changed to a UL symbol or a DL symbol through individual configuration.

[0309] The base station can additionally configure a symbol direction for each terminal. This symbol direction can be configured for each terminal via RRC signaling during the random access procedure. Specifically, a terminal-specific (UE-specific) symbol direction can be configured for each terminal via tdd-UL-DL-ConfigurationDedicated. The directions of the cell common UL symbol and cell common DL symbol have already been determined, so it is impossible to modify their directions further, and the cell common flexible symbol can be configured to have a terminal-specific symbol direction. The terminal-specific symbol direction can be determined to correspond to one of the terminal-specific UL symbol, terminal-specific DL symbol, and terminal-specific flexible symbol. A terminal-specific UL symbol indicates a symbol used only in uplink transmissions. A terminal-specific DL symbol indicates a symbol used only in downlink transmissions. A terminal-specific flexible symbol is a symbol whose specific direction has not yet been determined, and indicates a symbol that can be changed to a UL symbol or a DL symbol through individual configuration.

[0310] The terminal is configured with the cell common symbol direction via SIB1 received before receiving RRC signaling, and the terminal can retransmit Msg3 PUSCH. Therefore, depending on the cell common symbol direction, the terminal needs to retransmit Msg3 PUSCH. The terminal cannot determine whether the cell common flexible symbol is available for retransmission of Msg3 PUSCH. For example, the base station can configure the cell common flexible symbol as a terminal-specific DL symbol for different terminals. In this case, when a terminal retransmits Msg3 PUSCH using the cell common flexible symbol, it may interfere with different terminals. Therefore, it is necessary to determine whether the cell common flexible symbol is available for retransmission of Msg3 PUSCH; the method for this determination will be described below.

[0311] Figure 27 and Figure 28 The illustration shows resources available for repeated transmission of Msg3 PUSCH according to an embodiment of the present disclosure. Figure 27 and Figure 28The D time slot can indicate the time slot of at least one symbol among the symbols scheduled to be transmitted by Msg3PUSCH that overlaps with the cell common DL symbol. The U time slot can indicate the time slot of all symbols scheduled to be transmitted by Msg3PUSCH that overlap with the cell common UL symbol. The F time slot can indicate the time slot of at least one symbol among the symbols scheduled to be transmitted by Msg3PUSCH that overlaps with the cell common flexible symbol (the symbol scheduled to be transmitted by Msg3PUSCH may not overlap with the cell common DL symbol, but may overlap with the cell common UL symbol).

[0312] refer to Figure 27 The terminal can be configured to repeatedly transmit Msg3PUSCH over six consecutive time slots. Msg3PUSCH can be transmitted on time slots where it is possible to transmit, and it can also be omitted and discarded on time slots where transmission of Msg3PUSCH is not possible. i) See reference Figure 27 (a) A terminal may retransmit Msg3 PUSCH on the remaining time slots except for time slot D. That is, a terminal may retransmit Msg3 PUSCH on time slots F and U, and may not transmit and discard Msg3 PUSCH scheduled on time slot D. However, the cell common flexible symbol can be used to transmit Msg3 PUSCH, which may interfere with different terminals. (ii) See reference. Figure 27 (b) The terminal may repeatedly transmit the Msg3 PUSCH only on the U time slot. That is, the terminal may not transmit and may discard the Msg3 PUSCH scheduled on the D and F time slots. The terminal transmits the Msg3 PUSCH using only the UL symbol, thus avoiding interference with different terminals. iii) See reference. Figure 27 (c) The terminal may perform the first transmission of Msg3 PUSCH in the time slot indicated by the uplink permission (i.e., the time slot for the first transmission in the repeated transmission of Msg3 PUSCH), and may retransmit Msg3 PUSCH only in the U time slot following that time slot. After the time slot indicated by the uplink permission, the terminal may not transmit and may discard Msg3 PUSCH scheduled in the F and D time slots. The time slot indicated by the uplink permission may be determined based on the K2 value and the time slot in which the uplink permission was received. The K2 value is configured by the base station and may represent the offset value from the time slot in which the uplink permission was received. That is, if the time slot in which the uplink permission was received is the nth time slot, then the time slot indicated by the uplink permission may be the (n+k2)th time slot. The time slot indicated by the uplink permission may be either the F time slot or the U time slot. The base station may intentionally configure the cell common flexible symbol for the transmission of Msg3PUSCH.

[0313] refer to Figure 28 The terminal can be configured to repeatedly transmit Msg3 PUSCH four times, that is, to repeatedly transmit Msg3 PUSCH in four time slots. Therefore, the terminal needs to determine whether the repeated transmission of Msg3 PUSCH is possible in four time slots. i) Reference Figure 28 (a) A terminal may designate the remaining time slots, excluding time slot D, as time slots where Msg3 PUSCH may be transmitted. That is, a terminal may repeatedly transmit Msg3 PUSCH on time slots F and U. However, the cell common flexible symbol can be used to transmit Msg3 PUSCH, which may interfere with different terminals. (ii) See reference. Figure 28 (b) The terminal may retransmit Msg3PUSCH only on the U time slot. That is, the terminal cannot retransmit Msg3PUSCH on both the F and U time slots. Even with reference... Figure 28 Compared to the method described in (a) (method i), Msg3 PUSCH is repeatedly transmitted in later time slots, and only in time slot U, so different terminals may not be affected by interference. iii) Reference Figure 28 (c) The terminal may perform the first transmission of Msg3PUSCH in the time slot indicated by the uplink permission (i.e., the time slot for the first transmission in the repeated transmission of Msg3 PUSCH), and may retransmit Msg3PUSCH only on the U time slot following that time slot. The terminal may not transmit and may discard Msg3 PUSCH scheduled on the F and D time slots following the time slot indicated by the uplink permission. The time slot indicated by the uplink permission may be determined based on the K2 value and the time slot in which the uplink permission is received. The K2 value is configured by the base station and may represent the offset value from the time slot in which the uplink permission is received. That is, if the time slot in which the uplink permission is received is the nth time slot, then the time slot indicated by the uplink permission may be the (n+K2)th time slot. The time slot indicated by the uplink permission may be the F time slot or the U time slot. The base station may intentionally configure the cell common flexible symbol for the transmission of Msg3 PUSCH.

[0314] The base station can be configured to use reference via uplink permission. Figure 27 and Figure 28 This is one of the described methods. The base station can configure a method for determining the time slots for repeatedly transmitting Msg3 PUSCH by using some bits in a specific field of uplink permission, and the terminal can repeatedly transmit Msg3 PUSCH based on the configured method. (See reference) Figure 27 and Figure 28The Msg3 PUSCH in the described method can imply the initial transmission and retransmission of Msg3 PUSCH.

[0315] In the above description, the cell common DL symbol may further include symbols configured with a type 0 common search space (CSS) of CORESET0. Here, CORESET0 indicates the CORESET indicated by the Physical Broadcast Channel (PBCH). Here, the type 0 common search space is the search space of DCI format 1_0 used for monitoring and scheduling the transmission of PDSCH for SIB1. The DCI format may have a CRC scrambled by SI-RNTI. That is, the terminal will treat the received symbols of type 0 CSS configured with CORESET0 as symbols where downlink reception is possible only.

[0316] The cell common DL symbol may further include a symbol configuring the type 0A common search space (CSS) for CORESET0. The type 0A CSS may be a search space for monitoring the DCI, which is a DCI format 1_0 that schedules PDSCHs of SIBs other than SIB1. The DCI may have a CRC scrambled by SI-RNTI. The cell common DL symbol may further include a symbol configuring the type 1 CSS for CORESET0. The type 1 CSS may be a search space for monitoring the DCI that schedules Msg2 PDSCH or Msg4 PDSCH. The DCI may have a CRC scrambled by RA-RNTI, MsgB-RNTI, or TC-RNTI. The cell common DL symbol may further include a symbol configuring the type 2 CSS for CORESET0. The type 2 CSS may be a search space for monitoring the DCI that sends paging information. The DCI may have a CRC scrambled by P-RNTI. The cell common DL symbol may further include a symbol configuring the type 3 CSS for CORESET0. Type 3CSS can be a search space for monitoring DCIs with various cell common DCI formats. The DCI can have CRC scrambled by INT-RNTI, SFI-RNTI, TPC-PUSCH-RNTI, TPC-PUCCH-RNTI, TPC-SRS-RNTI, CI-RNTI, C-RNTI, MCS-C-RNTI, CS-RNTI, or PS-RNTI.

[0317] The cell common DL symbols may further include symbols configured to receive SS / PBCH blocks. Symbols configured to receive SS / PBCH blocks can be configured via SIB1, and specifically via SIB1's ssb-PositionsInBurst. That is, the terminal can determine the symbols configured to receive SS / PBCH blocks as those where reception of only the downlink channel is possible.

[0318] The cell common UL symbol may further include symbols configured to transmit PRACH. Symbols configured to transmit PRACH may correspond to valid RACH timings (ROs). The terminal can receive PRACH configuration from the base station via SIB1. Specifically, the PRACH configuration can be configured via the `rach-ConfigCommon` method of `ServingCellConfigCommonSIB`'s `UplinkConfigCommonSIB`'s `initialUplinkBWP`. The terminal can determine valid ROs through the PRACH configuration. The method for determining valid ROs will be described below.

[0319] a. If tdd-UL-DL-ConfigurationCommon is not configured for the terminal, then it is not before the SS / PBCH block and is spaced N from the last symbol of the SS / PBCH block. gap A valid RO can be identified if it has one or more symbols.

[0320] b. If tdd-UL-DL-ConfigurationCommon is configured for the terminal, then all its symbols that overlap with the cell's common UL symbol (RO) or are not before the SS / PBCH block and are separated from the last symbol of the SS / PBCH block by N. gap A valid RO can be identified if it has one or more symbols.

[0321] A terminal can transmit PRACH by using a valid RO. That is, the base station can assume that a valid RO is used for uplink channel transmission. The cell common UL symbol may include the N preceding the valid RO. gap The symbol for scheduling the transmission of PRACH can be the symbol corresponding to a valid RO. This is because the terminal is not in N. gap The base station receives downlink channels or signals in each symbol. Therefore, the base station can consider N as... gap One symbol is used for uplink transmission. If the subcarrier spacing of PRACH is 1.25kHz or 5kHz, then N gap It can be 0, but if the subcarrier spacing of PRACH is 15kHz, 30kHz, 60kHz, or 120kHz, then Ngap It can be 2.

[0322] Frequency hopping method for repeated transmissions in the uplink channel

[0323] The frequency hopping method used when a terminal repeatedly transmits uplink channels will be described below.

[0324] The base station can configure long PUCCHs (i.e., PUCCH formats 1, 3, and 4) to be repeatedly transmitted in two, four, or eight time slots for PUCCH coverage of the terminal. When the terminal enters RRC_connected mode after initial cell access, the PUCCH retransmission count (nrofSlots) for each PUCCH format can be configured for the terminal using terminal-specific system information. For example, if the PUCCH formats transmitted on the resources configured for the terminal include all PUCCH formats 1, 3, and 4, the retransmission counts for the corresponding PUCCH formats can be configured as different PUCCH retransmission counts (nrofSlots).

[0325] If a terminal is configured to repeat PUCCH transmission N times, then it can be determined that there are N possible time slots for PUCCH transmission, starting sequentially from the time slots configured or indicating PUCCH transmission. Regarding the possible time slots for PUCCH transmission, the symbols of the time slots scheduled to transmit PUCCH need not overlap with DL symbols configured as semi-static or symbols configured to receive SS / PBCH blocks. If a symbol scheduled to transmit PUCCH overlaps with a DL symbol configured as semi-static or a symbol configured to receive SS / PBCH blocks, then the terminal may not transmit PUCCH in the corresponding time slot, and the corresponding time slot may not be included in the N time slots used for PUCCH transmission.

[0326] Before completing PUCCH retransmission performed with a PUCCH retransmission count preconfigured by a base station, the base station may configure a new PUCCH retransmission for a terminal. When the terminal enters the RRC_connected mode after initial cell access, the terminal has been configured via terminal-specific system information to repeat the transmission of the PUCCH N times. However, if the channel environment becomes better thereafter, the terminal may be newly configured to repeat the transmission of the PUCCH M (< N) times in order to reduce the overhead of the uplink control channel and reduce uplink interference. On the other hand, if the channel environment deteriorates, the terminal may be newly configured to repeat the transmission of the PUCCH M ( > N) times in order to increase the coverage of the uplink control channel. Here, the retransmission count (M) may include 1. That is, if the terminal receives a configuration for retransmitting a new PUCCH, the terminal may ignore the configuration for retransmitting the previously configured PUCCH and may repeat transmitting the new PUCCH based on the configuration for retransmitting the new PUCCH.

[0327] The terminal can receive explicit information from the base station to determine the retransmission count of a new PUCCH. The explicit information can be the PUCCH retransmission count. The explicit information can be included in a DCI, which is included in the PDCCH that schedules the PDSCH corresponding to the PUCCH. The PDSCH corresponding to the PUCCH can be a PUCCH that includes HARQ-ACK information for the corresponding PDSCH. When the available retransmission count of the PUCCH is K, the explicit information can be indicated by the size of ceil(log2(K)) bits. For example, if the available retransmission counts of the PUCCH are 1, 2, 4, and 8, then K equals 4 (K = 4), so ceil(log2(4)) = 2 bits can be used for indication. The indicable retransmission count of the PUCCH can be one of {1, 2, 4, 8}. The base station can configure multiple retransmission counts of the PUCCH from the indicable retransmission counts of the PUCCH as explicit information. For example, the base station can configure {2, 4} from the PUCCH retransmission counts {1, 2, 4, 8} as explicit information. The indicative repeat transmission count of a PUCCH can be one of {1, 2, 4, 8, N}. N can be pre-configured for each PUCCH format. The base station can configure multiple repeat transmission counts of the PUCCH from the indicative repeat transmission counts as explicit information. The multiple repeat transmission counts of the PUCCH configured as explicit information can include N. For example, the base station can configure {2, N} from the PUCCH repeat transmission counts {1, 2, 4, 8, N} as explicit information. The indicative repeat transmission count of a PUCCH can include at least one of {N / 4, N / 2, N, 2*N, 4*N}. The base station can configure {N / 2, N} as the PUCCH repeat transmission count. If N / 4 is configured as explicit information, the terminal can repeat the PUCCH transmission N / 4 times (i.e., once if N = 4, and twice if N = 8), where N is pre-configured. Similarly, if N / 2 is configured as an explicit message, the terminal can repeat the PUCCH transmission N / 2 times (i.e., once if N=2, twice if N=4, and four times if N=8), where N is pre-configured. If 2*N is configured as an explicit message, the terminal can repeat the PUCCH transmission 2N times (i.e., twice if N=1, four times if N=2, and eight times if N=4). If 4*N is configured as an explicit message, the terminal can repeat the PUCCH transmission 4N times (i.e., four times if N=1, and eight times if N=2). If N / 4 and N / 2 are less than 1, the PUCCH retransmission count can be 1. If 2*N and 4*N are greater than 8, the PUCCH retransmission count can be 8.

[0328] In conventional methods, different PUCCH retransmission counts can be configured for corresponding PUCCH formats. Even when a new resource for PUCCH transmission is configured for the terminal and the terminal performs a new PUCCH transmission, if the previous PUCCH format is the same as the newly configured PUCCH format, the terminal can retransmit the newly configured PUCCH using the retransmission count corresponding to the PUCCH format. For example, a PUCCH format transmitted in a resource with a PUCCH resource ID configured as 0 can be configured as PUCCH format 1 with a retransmission count of 8, and a PUCCH format transmitted in a resource with a PUCCH resource ID configured as 1 can be configured as PUCCH format 1 with a retransmission count of 2. Subsequently, if the PUCCH resource ID indicated by the PUCCH resource indicator (PRI) field of the DCI included in the PDCCH corresponding to the PUCCH PDSCH is 0, the terminal can repeatedly transmit PUCCH with PUCCH format 1 on eight time slots; if the PUCCH resource ID is 1, the terminal can repeatedly transmit PUCCH with PUCCH format 1 on two time slots. The PUCCH retransmission count for each resource in which PUCCH is transmitted can be a value of {1, 2, 4, 8}. If no PUCCH retransmission count is configured in the resource in which PUCCH is transmitted, the terminal can repeatedly transmit PUCCH according to the retransmission count configured according to the PUCCH format.

[0329] The following describes a method for configuring frequency hopping by the base station when the terminal is configured to repeatedly transmit PUCCH.

[0330] Frequency hopping within time slots

[0331] The terminal can divide the PUCCH into two halves in the time domain, map the two halves to two hops in a time slot configured to transmit the PUCCH, and then transmit the two hops to the base station. The PUCCH can be transmitted repeatedly or not. When the length (number) of symbols allocated in a time slot to allow PUCCH transmission is called the symbol count, floor(symbol count / 2) symbols can be mapped to the first hop, and symbol count - floor(symbol count / 2) symbols can be mapped to the second hop. The first hop can be transmitted in a first frequency band, and the second hop can be transmitted in a second frequency band. The first hop can be configured with an equal number of PRBs, starting from the PRB corresponding to the starting PRB index configured by the base station. The second hop can be configured with an equal number of PRBs, starting from the PRB corresponding to the PRB index configured by the base station (from which the second hop begins).

[0332] Inter-slot frequency hopping

[0333] The time slot indices for repeated transmission (repetition) can be sequentially indexed based on the first time slot of the PUCCH retransmission relative to the time slot in which the first PUCCH is transmitted. The retransmission index for the time slot of the first PUCCH can be 0. The time slot indices for repeated transmission can be sequentially indexed for time slots after the time slot of the first PUCCH transmission. The time slot indices for repeated transmission can be determined regardless of whether repeated transmission of the PUCCH is possible in the corresponding time slot. For example, if the terminal is configured to transmit the PUCCH four times in time slot X, the terminal can determine 0 as the index for time slot X, 1 as the index for time slot X+1, 2 as the index for time slot X+2, and 3 as the index for time slot X+3. Based on the determined time slot indices for repeated transmission, the terminal can map the PUCCH to the first hop in the time slot corresponding to the even-numbered time slot indices for repeated transmission. The terminal can map the PUCCH to the second hop in a time slot corresponding to an odd-numbered time slot index used for repeated transmission. The first hop can be transmitted in a first frequency band, and the second hop can be transmitted in a second frequency band. The first hop can be configured with an equal number of PRBs, starting from the PRB corresponding to the starting PRB index configured by the base station. The second hop can be configured with an equal number of PRBs, starting from the PRB corresponding to the PRB index configured by the base station (from which the second hop begins).

[0334] PUCCH frequency hopping method

[0335] The base station can configure the terminal to perform either intra-slot frequency hopping or inter-slot frequency hopping.

[0336] The base station can configure whether to perform intra-slot frequency hopping for each resource configured for PUCCH transmission. For example, when configuring a terminal to have a resource with PUCCH resource ID 1 in a resource set with PUCCH resource set ID 0, the base station can configure whether intra-slot frequency hopping is possible. If the base station configures intra-slot frequency hopping as possible, the terminal can transmit PUCCH via intra-slot frequency hopping; if the base station configures intra-slot frequency hopping as impossible, the terminal can transmit PUCCH without intra-slot frequency hopping.

[0337] The base station can configure whether to perform inter-slot frequency hopping for each PUCCH format. For example, the base station can configure whether inter-slot frequency hopping is possible for a PUCCH with PUCCH format 1. If the base station configures inter-slot frequency hopping as possible, the terminal can transmit the PUCCH via inter-slot frequency hopping, regardless of the resources configured for the PUCCH. If the base station configures inter-slot frequency hopping as impossible, the terminal can transmit the PUCCH based on the resources configured for the PUCCH. In other words, the terminal can transmit the PUCCH based on the availability of intra-slot frequency hopping configured for each resource configured for PUCCH transmission.

[0338] If inter-slot frequency hopping is possible for a specific PUCCH format, the terminal can expect that there is no configuration for intra-slot frequency hopping regarding resources for transmitting PUCCHs with that specific PUCCH format. In other words, if the base station makes inter-slot frequency hopping configuration possible according to the PUCCH format, the base station can, based on the resources available for transmitting PUCCHs, not perform configuration for intra-slot frequency hopping.

[0339] A base station can configure intra-slot hopping for a PUCCH with a specific PUCCH format that is initially repeatedly transmitted, and configure a retransmission count (N) greater than 1. Subsequently, a new PUCCH can be configured with a retransmission count of 1 for the terminal. Intra-slot hopping is configured to be possible, and therefore, it is possible for the terminal not to configure inter-slot frequency hopping for the corresponding PUCCH. That is, when inter-slot frequency hopping is configured for a PUCCH with a specific PUCCH format, the new PUCCH is not transmitted via intra-slot frequency hopping regardless of its retransmission count. Therefore, a method is needed to determine the frequency hopping method based on the retransmission count of the new PUCCH.

[0340] Figure 29 The illustration shows a method for determining a frequency hopping method based on the repetition count of PUCCH according to an embodiment of the present disclosure.

[0341] The terminal can determine the frequency hopping method by interpreting higher-layer fields differently based on the repetition count of the new PUCCH. Specifically, the terminal can interpret the intra-slot frequency hopping value or inter-slot frequency hopping value in the higher-layer fields based on whether the PUCCH repetition count is 1. (See reference) Figure 29`nrofSlots` represents the PUCCH retransmission count configured by the base station, and `intraSlotFrequencyHopping` indicates whether intra-slot frequency hopping can be performed. If `intraSlotFrequencyHopping` is configured to be enabled, intra-slot frequency hopping can be performed; otherwise, it will not. `interslotFrequencyHopping` indicates whether inter-slot frequency hopping is performed. If `interslotFrequencyHopping` is configured to be enabled, inter-slot frequency hopping can be performed; otherwise, it will not. If the retransmission count of a new PUCCH is 1, the terminal can determine whether intra-slot frequency hopping is enabled, regardless of whether it is configured at a higher layer. If intra-slot frequency hopping is configured to be enabled, the terminal can perform intra-slot frequency hopping for the new PUCCH and transmit it. If the retransmission count of the new PUCCH is not 1, the terminal can first identify whether inter-slot frequency hopping is configured to be enabled at a higher layer. If inter-slot frequency hopping is configured to be enabled, the terminal can perform inter-slot frequency hopping for the new PUCCH and retransmit the new PUCCH. A PUCCH can be transmitted solely through inter-slot frequency hopping, regardless of whether intra-slot frequency hopping is configured. If inter-slot frequency hopping is not configured to be enabled, the terminal can identify whether intra-slot frequency hopping is configured to be enabled at a higher layer. If intra-slot frequency hopping is enabled, the terminal can perform intra-slot frequency hopping for the new PUCCH and retransmit the new PUCCH; if intra-slot frequency hopping is not configured to be enabled, the terminal can retransmit the PUCCH without performing frequency hopping.

[0342] In other words, the possibility of inter-slot frequency hopping can be configured for the terminal for each PUCCH format. The possibility of intra-slot frequency hopping can be configured for the terminal for each resource configured to send PUCCHs. Additionally, a PUCCH retransmission count can be configured for the terminal. The terminal can determine whether to perform inter-slot frequency hopping based on the retransmission count and the possibility of intra-slot frequency hopping in the resource configured to send PUCCHs. If the retransmission count is 1, inter-slot frequency hopping may not be performed. If the retransmission count is greater than 1 and inter-slot frequency hopping is configured as possible according to the PUCCH format, the terminal can perform inter-slot frequency hopping regardless of whether intra-slot frequency hopping is configured. Conversely, if the retransmission count is greater than 1 and inter-slot frequency hopping is configured as impossible according to the PUCCH format, the terminal can perform frequency hopping depending on whether intra-slot frequency hopping is configured.

[0343] PUSCH frequency hopping method

[0344] The frequency hopping method for PUSCH will be described below. The frequency hopping method for PUSCH can be configured from a higher layer.

[0345] For example, a terminal can determine the frequency hopping method by interpreting the bits of the frequency hopping flag in the DCI corresponding to the new PUSCH differently based on the repetition count of the new PUSCH. The DCI can be the DCI of the PDCCH that schedules the PUSCH. Specifically, the terminal can interpret the 1-bit frequency hopping flag differently depending on whether the repetition count of the new PUSCH is 1. i) If the repetition count of the new PUSCH configured for the terminal is 1 and the bit value of the frequency hopping flag is 0, the terminal can send the PUSCH without performing frequency hopping. ii) If the repetition count of the new PUSCH configured for the terminal is 1 and the bit value of the frequency hopping flag is 0, the terminal can perform intra-slot frequency hopping to send the PUSCH. iii) If the repetition count of the new PUSCH configured for the terminal is greater than 1 and the bit value of the frequency hopping flag is 0, the terminal can perform intra-slot frequency hopping to send the PUSCH. iv) If the repetition count of the new PUSCH configured for the terminal is greater than 1 and the bit value of the frequency hopping flag is 1, the terminal can perform inter-slot frequency hopping to repeatedly send the PUSCH. As another example, i) if the retransmission count of the new PUSCH configured for the terminal is 1 and the bit value of the frequency hopping flag is 0, the terminal can transmit the PUSCH without performing frequency hopping. ii) if the retransmission count of the new PUSCH configured for the terminal is 1 and the bit value of the frequency hopping flag is 0, the terminal can perform intra-slot frequency hopping to transmit the PUSCH. iii) if the retransmission count of the new PUSCH configured for the terminal is greater than 1 and the bit value of the frequency hopping flag is 0, the terminal can repeatedly transmit the PUSCH without performing frequency hopping. iv) if the retransmission count of the new PUSCH configured for the terminal is greater than 1 and the bit value of the frequency hopping flag is 1, the terminal can perform inter-slot frequency hopping to repeatedly transmit the PUSCH.

[0346] The repetition count and frequency hopping method for a new PUSCH can be determined by configuring the terminal with a repetition count and frequency hopping method. The terminal can interpret the bits of the frequency hopping flag corresponding to the DCI of the new PUSCH differently. The DCI corresponding to the new PUSCH can be the DCI of the PDCCH that schedules the PUSCH. Specifically, the repetition count and frequency hopping method for the new PUSCH can be configured by the base station for the terminal in pairs (i.e., repetition count and frequency hopping method) corresponding to the DCI of the new PUSCH, and the terminal can send the new PUSCH. Here, the number of (repetition count, frequency hopping method) pairs can be configured to up to 2. The frequency hopping method can be one of three cases: intra-slot frequency hopping, inter-slot frequency hopping, or no frequency hopping.

[0347] Msg3PUSCH frequency hopping method

[0348] The aforementioned new PUSCH can be a new Msg3 PUSCH scheduled by an uplink license in a random access response. The retransmission count of the new Msg3 PUSCH can be included in the uplink license. The frequency hopping method for retransmissions of the new Msg3 PUSCH will be described below.

[0349] The base station can configure a frequency hopping method for retransmitting new Msg3 PUSCH for frequency diversity gain. The frequency hopping method can be configured by the value of a 1-bit value of the frequency hopping flag in the uplink permission of the random access response scheduling the new Msg3 PUSCH. In the case of retransmitting Msg3 PUSCH, the frequency hopping method can be configured by the value of a 1-bit value of the frequency hopping flag in the DCI, which is a DCI format 0_0 scrambled by TC-RNTI that schedules the retransmission of Msg3 PUSCH. If the frequency hopping flag bit value is 0, the terminal can retransmit the new Msg3 PUSCH without performing frequency hopping, and if the frequency hopping flag bit value is 1, the terminal can perform intra-slot frequency hopping to retransmit the new Msg3 PUSCH. In the case of the terminal retransmitting Msg3 PUSCH, if inter-slot frequency hopping is possible, inter-slot frequency hopping may be more advantageous than intra-slot frequency hopping in terms of DMRS overhead. The following describes a method by which a terminal performs inter-slot frequency hopping to repeatedly transmit a new Msg3 PUSCH.

[0350] The terminal can determine the frequency hopping method by interpreting the bits of the frequency hopping flag based on the retransmission count of the new Msg3 PUSCH. Specifically, the terminal can interpret the frequency hopping flag differently from the conventional method based on whether the retransmission count of the new Msg3 PUSCH is 1. For example, i) if the retransmission count of the new Msg3 PUSCH configured for the terminal is 1 and the bit value of the frequency hopping flag is 0, the terminal can repeatedly transmit the new Msg3 PUSCH without performing frequency hopping. ii) if the retransmission count of the new Msg3 PUSCH configured for the terminal is 1 and the bit value of the frequency hopping flag is 0, the terminal can perform intra-slot frequency hopping to transmit the new Msg3 PUSCH. iii) if the retransmission count of the new Msg3 PUSCH configured for the terminal is greater than 1 and the bit value of the frequency hopping flag is 0, the terminal can perform intra-slot frequency hopping to repeatedly transmit the new Msg3 PUSCH. iv) If the retransmission count of the new Msg3 PUSCH configured for the terminal is greater than 1 and the bit value of the frequency hopping flag is 1, the terminal may perform inter-slot frequency hopping to repeatedly transmit the new Msg3 PUSCH. As another example, i) If the retransmission count of the new Msg3 PUSCH configured for the terminal is 1 and the bit value of the frequency hopping flag is 0, the terminal may transmit the new Msg3 PUSCH without performing frequency hopping. ii) If the retransmission count of the new Msg3 PUSCH configured for the terminal is 1 and the bit value of the frequency hopping flag is 1, the terminal may perform intra-slot frequency hopping to transmit the new Msg3 PUSCH. iii) If the retransmission count of the new Msg3 PUSCH configured for the terminal is greater than 1 and the bit value of the frequency hopping flag is 0, the terminal may determine to repeatedly transmit the new Msg3 PUSCH without performing frequency hopping. iv) If the repeat transmission count of the new Msg3 PUSCH configured for the terminal is greater than 1 and the bit value of the frequency hopping flag is 1, the terminal may perform inter-slot frequency hopping to repeatedly transmit the new Msg3 PUSCH.

[0351] The repetition count and frequency hopping method for the new Msg3 PUSCH can be determined by configuring the terminal with a repetition count and frequency hopping method, and the terminal can interpret the frequency hopping flag bits differently. Specifically, the repetition count and frequency hopping method for the new PUSCH can be configured by the base station for the terminal in the form of a pair (i.e., repetition count and frequency hopping method) corresponding to the DCI of the new PUSCH, and the terminal can send the new Msg3 PUSCH. Specifically, the pair indicating the repetition count and frequency hopping method of the new PUSCH can be determined by the uplink permission of the random access response scheduling the Msg3 PUSCH or the frequency hopping flag of the DCI as DCI format 0_0. Here, the number of (repetition count, frequency hopping method) pairs can be configured to up to 2. The frequency hopping method can be one of three cases: intra-slot frequency hopping, inter-slot frequency hopping, and no frequency hopping.

[0352] Figure 30 This is a flowchart illustrating a method for a terminal to send Msg3 PUSCH according to an embodiment of the present disclosure.

[0353] In the following text, reference will be made to Figure 30 Description Reference Figures 1 to 29 The method described is for the terminal to send Msg3PUSCH.

[0354] The terminal can receive System Information Block 1 (SIB1) from the base station (operation S3010). System Information Block 1 can be a different System Information Block as described above (e.g., SIBx, x = 1, 2, 3…). The terminal can send a preamble for the random access procedure to the base station (operation S3020). The terminal can receive a Random Access Response (RAR) for the preamble from the base station (operation S3030). The Random Access Response can include information scheduling the Physical Uplink Shared Channel (PUSCH) to be sent by the terminal to the base station. The terminal can send the PUSCH to the base station based on the Random Access Response (operation S3040). SIB1 can include information about a candidate set of repetition counts, which includes one or more repetition count values ​​for repeated transmissions of the PUSCH. The Random Access Response can include information indicating one of the values ​​of one or more repetition counts included in the candidate set of repetition counts. The transmission of the PUSCH can be repeated as many times as that one value. The Random Access Response can correspond to a Physical Downlink Shared Channel (PDSCH) including uplink (UL) clearance. Information indicating a value may be included in at least one of the Time Domain Resource Assignment (TDRA), Modulation and Coding Scheme (MCS), and Transmission Power Control (TPC) fields of the random access response. When information indicating a value is included in the MCS field, the value may be indicated by one or more most significant bits (MSBs) of the MCS field. When information indicating a value is included in the TPC field, the value may be indicated by one or more least significant bits (LSBs) of the TPC field. Each value of the one or more repetition counts may be a power of 2. Specifically, the values ​​of the one or more repetition counts may be 1, 2, 4, and 8, respectively. SIB1 may include at least one of preamble-related information and RACH timing. Additionally, PUSCH may be transmitted in resources determined based on at least one of the preamble-related information and RACH timing.

[0355] After operation S3040, the terminal can receive downlink control information (DCI) from the base station, including information for scheduling retransmission PUSCH. The terminal can repeatedly send retransmission PUSCH to the base station based on the DCI. The information for scheduling retransmission PUSCH may include information about the repetition count of the retransmission PUSCH. This repetition count information can be included in the HARQ process number field of the DCI. The retransmission PUSCH can be the same as the PUSCH sent by the terminal in operation S3040. The base station can send the DCI when it fails to receive the PUSCH sent by the terminal. That is, if the base station fails to successfully receive the PUSCH sent by the terminal in operation S3040, the base station can send information for scheduling retransmission PUSCH to the terminal.

[0356] The random access response may include a frequency hopping flag indicating whether the PUSCH performs frequency hopping. Based on this value and the frequency hopping flag, the PUSCH may undergo intra-slot frequency hopping or inter-slot frequency hopping. When the value is 1, the PUSCH may perform intra-slot frequency hopping when the frequency hopping flag indicates that the PUSCH should perform frequency hopping. When the value of the frequency hopping flag indicates that the PUSCH should not perform frequency hopping, the PUSCH may not perform frequency hopping. When the value is greater than 1, the PUSCH may perform inter-slot frequency hopping when the frequency hopping flag indicates that the PUSCH should perform frequency hopping. When the value of the frequency hopping flag indicates that the PUSCH should not perform frequency hopping, the PUSCH may not perform frequency hopping. The PUSCH may be a retransmitted PUSCH.

[0357] The random access response may further include information about the resources for performing the first retransmission of PUSCH. This information may be a time slot offset between the resources receiving the random access response and the resources performing the first retransmission of PUSCH. SIB1 may further include information related to Time Division Duplex (TDD) configuration, and this TDD configuration information may be information about the symbol type of the configured time slot. The symbol type may be one of the following: a downlink symbol configured for downlink transmission, an uplink symbol configured for uplink transmission, and a flexible symbol not determined as either a downlink or uplink symbol. PUSCH may be retransmitted in time slots. The resources for performing the first retransmission of PUSCH may be resources spaced apart from the resources receiving the random access response by a time slot offset. The resources for performing the first retransmission of PUSCH may be flexible time slots, and retransmissions following the first retransmission of PUSCH may be performed on uplink time slots. Flexible time slots may be configured by including at least one flexible symbol, and the entire uplink time slot may be configured by uplink symbols. PUSCH can be a retransmission PUSCH.

[0358] Execution Reference Figure 30 The terminal of the described method may be a reference. Figure 11 The terminal described herein may specifically include a communication module configured to transmit or receive radio signals, and a processor configured to control the communication module. In this case, the terminal's processor may execute the method for transmitting Msg 3PUSCH described herein.

[0359] Additionally, the base station described in this specification for receiving Msg3 PUSCH transmitted by a terminal may include a communication module configured to transmit or receive radio signals, and a processor configured to control the communication module. In this case, the base station may be related to... Figure 11 The base station is described. The base station's processor can execute the method described in this specification for receiving Msg3 PUSCH sent by the UE.

[0360] The methods and systems disclosed herein are described with respect to specific embodiments, but some or all of the configuration elements and operations of this disclosure may be implemented using a computer system with a general hardware architecture.

[0361] The foregoing description of this disclosure is for illustrative purposes, and those skilled in the art to which this disclosure pertains will understand that modifications to other specific forms can be readily implemented without altering the technical spirit or essential features of this disclosure. Therefore, it should be understood that the above embodiments are illustrative in all respects and not restrictive. For example, each element described as being of one type may be implemented in a distributed manner, and similarly, elements described as being distributed may be implemented in a combined manner.

[0362] The scope of this disclosure is indicated by the claims described below rather than by a detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of this disclosure.

Claims

1. A method performed by a user equipment configured to operate in a wireless communication system, the method comprising: Send a preamble for the random access procedure; Receive a Random Access Response (RAR) in response to the preamble. as well as Based on the RAR, Physical Uplink Shared Channel (PUSCH) repetition is performed. The RAR includes first information indicating whether the PUSCH repetition uses frequency hopping transmission, second information indicating the number of time slots used for the PUSCH repetition, and third information related to the offset k of the time slot used to determine the transmission of the PUSCH repetition. The second information is included in the modulation and coding scheme (MCS) field of the RAR, and the number of time slots used for the PUSCH repetition is indicated by the two most significant bits of the MCS field. Specifically, when the PUSCH repeats using frequency hopping transmission, the number of time slots used for the PUSCH repeat determines whether the frequency hopping mode of the PUSCH repeat is intra-slot frequency hopping or inter-slot frequency hopping. Wherein, time slot n is the last time slot in which the RAR is received. The PUSCH is repeatedly transmitted starting from the beginning of the time slot. The initial time slot is determined based on time slot n+k. The resources used to send the PUSCH repetition do not include downlink symbols, and the downlink symbols are configured as cell common via higher-layer signaling.

2. The method according to claim 1, wherein When the number of time slots used for PUSCH repetition is 1, the frequency hopping mode of PUSCH repetition is intra-slot frequency hopping. Wherein, when the number of time slots used for PUSCH repetition is 2 or more, the frequency hopping mode of PUSCH repetition is inter-time slot frequency hopping.

3. The method according to claim 1, wherein, The RAR is received via the Physical Downlink Shared Channel (PDSCH), and the RAR includes an uplink (UL) license.

4. The method according to claim 1, further comprising: Receive a set of one or more values ​​associated with the repetition of the PUSCH via System Information Block 1 (SIB 1). The two most significant bits of the MCS field indicate one or more of the values ​​as the number of time slots used for the PUSCH repetition.

5. The method of claim 1, further comprising: Receive downlink control information (DCI) for scheduling PUSCH retransmissions; as well as Based on the DCI, the retransmission PUSCH is sent. The DCI includes the number of repeating time slots used for the retransmission PUSCH.

6. The method according to claim 5, wherein, The DCI is scrambled by TC-RNTI (Temporary Cell Radio Network Temporary Identifier), and The DCI format is DCI format 0_0.

7. The method according to claim 4, wherein The one or more values ​​include powers of 2.

8. The method of claim 1, wherein, The PUSCH is repeatedly transmitted in time slots.

9. A user equipment configured to operate in a wireless communication system, the user equipment comprising: transceiver; as well as A processor configured to control the transceiver. The processor is configured as follows: Send a preamble for the random access procedure. Receive a Random Access Response (RAR) in response to the preamble; and Based on the RAR, Physical Uplink Shared Channel (PUSCH) repetition is performed. The RAR includes first information indicating whether the PUSCH repetition uses frequency hopping transmission, second information indicating the number of time slots used for the PUSCH repetition, and third information related to the offset k of the time slot used to determine the transmission of the PUSCH repetition. The second information is included in the modulation and coding scheme (MCS) field of the RAR, and the number of time slots used for the PUSCH repetition is indicated by the two most significant bits of the MCS field. Specifically, when the PUSCH repeats using frequency hopping transmission, the number of time slots used for the PUSCH repeat determines whether the frequency hopping mode of the PUSCH repeat is intra-slot frequency hopping or inter-slot frequency hopping. Wherein, time slot n is the last time slot in which the RAR is received. The PUSCH is repeatedly transmitted starting from the beginning of the time slot. The initial time slot is determined based on time slot n+k. The resources used to send the PUSCH repetition do not include downlink symbols, and the downlink symbols are configured as cell common via higher-layer signaling.

10. The user equipment according to claim 9, wherein When the number of time slots used for PUSCH repetition is 1, the frequency hopping mode of PUSCH repetition is intra-slot frequency hopping. Wherein, when the number of time slots used for PUSCH repetition is 2 or more, the frequency hopping mode of PUSCH is inter-time slot frequency hopping.

11. The user equipment according to claim 9, wherein The RAR is received via the Physical Downlink Shared Channel (PDSCH), and the RAR includes an uplink (UL) license.

12. The user equipment according to claim 9, The processor is configured as follows: Receive a set of one or more values ​​associated with the repetition of the PUSCH via System Information Block 1 (SIB 1). wherein, The two most significant bits of the MCS field indicate one or more of the values ​​as the number of slots used for the PUSCH repetition.

13. The user equipment according to claim 12, wherein The one or more values ​​include powers of 2.

14. The user equipment according to claim 9, wherein, The PUSCH is repeatedly transmitted in time slots.

15. A method performed by a base station configured to operate in a wireless communication system, the method comprising: Receive the preamble used in the random access procedure; Send a response to the preamble of the Random Access Response (RAR); as well as Based on the RAR receive physical uplink shared channel (PUSCH) repetition, The RAR includes first information indicating whether the PUSCH repetition uses frequency hopping transmission, second information indicating the number of time slots used for the PUSCH repetition, and third information related to the offset k of the time slot used to determine the transmission of the PUSCH repetition. The second information is included in the modulation and coding scheme (MCS) field of the RAR, and the number of time slots used for the PUSCH repetition is indicated by the two most significant bits of the MCS field. Specifically, when the PUSCH repeats using frequency hopping transmission, the number of time slots used for the PUSCH repeat determines whether the frequency hopping mode of the PUSCH repeat is intra-slot frequency hopping or inter-slot frequency hopping. Wherein, time slot n is the last time slot in which the RAR is transmitted. The PUSCH repeats are received from the start of the time slot. The initial time slot is determined based on time slot n+k. The resources used to receive the PUSCH repetition do not include downlink symbols, and the downlink symbols are configured as cell common via higher-layer signaling.

16. A base station configured to operate in a wireless communication system, the base station comprising: transceiver; as well as A processor configured to control the transceiver. The processor is configured as follows: Receive the preamble used in the random access procedure. Send a response to the Random Access Response (RAR) in the preamble; and Based on the RAR receive physical uplink shared channel (PUSCH) repetition, The RAR includes first information indicating whether the PUSCH repetition uses frequency hopping transmission, second information indicating the number of time slots used for the PUSCH repetition, and third information related to the offset k of the time slot used to determine the transmission of the PUSCH repetition. The second information is included in the modulation and coding scheme (MCS) field of the RAR, and the number of time slots used for the PUSCH repetition is indicated by the two most significant bits of the MCS field. Specifically, when the PUSCH repeats using frequency hopping transmission, the number of time slots used for the PUSCH repeat determines whether the frequency hopping mode of the PUSCH repeat is intra-slot frequency hopping or inter-slot frequency hopping. Wherein, time slot n is the last time slot in which the RAR is transmitted. The PUSCH repeats are received from the start of the time slot. The initial time slot is determined based on time slot n+k. The resources used to receive the PUSCH repetition do not include downlink symbols, and the downlink symbols are configured as cell common via higher-layer signaling.

Images