Method, user equipment and base station for initial cell access in a wireless communication system

Abstract

The present specification relates to a method, an apparatus, and a system for initial cell access in a wireless communication system. The present specification discloses a reduced capability user equipment (UE) including a communication module configured to receive configuration information for configuring a first downlink bandwidth part (DL BWP) and a first uplink bandwidth part (BWP) to be used for an initial access procedure, receive an indicator indicating a BWP access prohibition of the first user equipment in a second UL BWP and a second DL BWP of a legacy type second user equipment, and perform the initial access procedure via at least one of the first DL BWP, the first UL BWP, the second DL BWP, and the second UL BWP based on the indicator; and a processor controlling the reception of the configuration information, the performance of the initial access procedure, and the reception of the indicator. The RedCap user equipment can smoothly perform initial cell access, can perform a random access procedure without colliding with an existing legacy type user equipment, and can perform communication based on various types of frequency hopping designs.

Description

Technical Field

[0001] This disclosure relates to wireless communication systems, and more specifically, to initial cell access methods, apparatus, and systems in wireless communication systems, as well as apparatuses using the same. 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 spectrum efficiency and enables communication providers to offer more data and voice services within 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 calls. The advantages of the NR system include higher throughput and lower latency on the same platform, support for both Frequency Division Duplex (FDD) and Time Division Duplex (TDD), and lower operating costs due to the enhanced end-user environment and simpler architecture.

[0004] For more efficient data processing, the dynamic TDD of the NR system can use a method 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 cell users. For example, when the downlink traffic of a cell is greater than the uplink traffic, the base station can allocate multiple downlink OFDM symbols to a time slot (or subframe). Information about the time slot configuration should be sent to the terminal.

[0005] 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.

[0006] In 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, which combines IoT with big data processing through connections to cloud servers, is also emerging. To realize IoT, technological elements such as sensing technology, wired / wireless communication and network infrastructure, service interface technology, and security technology are required. This has led to the research in recent years 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.

[0007] Various attempts have been made to apply 5G communication systems to IoT networks. For example, technologies such as sensor networks, machine-to-machine (M2M) communication, and machine-type communication (MTC) are being implemented using techniques such as beamforming, MIMO, and array antennas, all of which are 5G communication technologies. The application of cloud radio access networks (cloud RAN), as a big data processing technology, can also be seen as an example of the convergence of 5G and IoT technologies. Typically, mobile communication systems have been developed to provide voice services while ensuring user activity.

[0008] In the 3GPP study on "Self-Assessment of IMT-2020 Submissions," NB-IoT and LTE M were identified as meeting the IMT-2020 requirements for mMTC, enabling NB-IoT and LTE M to be certified as 5G technologies. Regarding URLLC support, URLLC functionality was introduced for both LTE and NR in Rel-15, and further advancements have been made in Rel-16 with improved URLLC (enhanced URLLC (eURLLC)) and URLLC for NR systems in the Industrial IoT work item. Rel-16 also introduced 5G integration support and Time-Sensitive Networking (TSN) for TSC use.

[0009] One of the primary goals of 5G is to enable connected industries. 5G connectivity acts as a catalyst for next-generation industrial innovation and digitalization, improving flexibility, productivity and efficiency, reducing maintenance costs, and enhancing operational safety. For devices in this environment, it is expected that they will connect to 5G radio access and core networks, such as pressure sensors, humidity sensors, thermometers, motion sensors, accelerometers, and actuators. Use cases and requirements for large-scale industrial wireless sensor networks include URLLC services with very high requirements, as well as relatively inexpensive services with small device format requirements. These services should be available wirelessly for many years using battery power. Examples of services include industrial wireless sensors, video surveillance, and wearable devices. These services have higher requirements than Low Power Wide Area (LPWA) (i.e., LTE-M / NB-IoT) but lower requirements than URLLC and eMBB. Summary of the Invention

[0010] Technical issues

[0011] The technical objective of this disclosure is to provide an initial cell access method and apparatus in a wireless communication system (particularly a cellular wireless communication system).

[0012] Another technical objective of this disclosure is to provide a method and apparatus for frequency hopping for uplink data transmission in a wireless communication system (particularly a cellular wireless communication system).

[0013] Technical solution

[0014] According to aspects of this disclosure, a first UE (reduced capability UE) with reduced performance is provided in a wireless communication system. The first UE may include: a communication module configured to receive configuration information for configuring a first downlink bandwidth portion (DL BWP) and a first uplink bandwidth portion (Uplink BWP) used in an initial access procedure; receive an indicator indicating BWP access prohibition for the first UE in a second UL BWP and a second DL BWP for a legacy type second UE; and, based on the indicator, execute the initial access procedure via at least one of the first DL BWP, the first UL BWP, the second DL BWP, and the second UL BWP; and a processor configured to control the reception of the configuration information, the execution of the initial access procedure, and the reception of the indicator, wherein each of the first UL BWP and the second UL BWP is configured individually, the initial access procedure includes a random access procedure, the first UL BWP includes a first resource for the random access procedure of the first UE, and the first resource is identical to a second resource for the random access procedure on the second UL BWP of the second UE.

[0015] On one hand, the communication module can be configured to obtain information about the basic control resource set (CORESET) from a second synchronization signal block (SSB) associated with the second UE.

[0016] On the other hand, the communication module can be configured to receive information about the CORESET for the first UE via a system information block (System Information Block 1 (SIB1)), wherein the CORESET for the first UE and the CORESET for the second UE are defined separately.

[0017] On the other hand, the communication module can be configured to receive SIB1 for the second UE, wherein the SIB1 includes scheduling information about system information for performing the initial access procedure of the first UE.

[0018] On the other hand, the scheduling information may include information about the starting physical resource block (PRB) of the first DL BWP activated for performing the initial access procedure of the first UE.

[0019] On the other hand, the communication module can be configured to receive SIB1 for the second UE, wherein the SIB1 includes configuration information for a random access procedure for initial access of the first UE.

[0020] On the other hand, the communication module can be configured to obtain information about the CORESET for the first UE via a first SSB defined separately from the second SSB for the second UE.

[0021] On the other hand, the information about the basic CORESET may include 8 bits, and 4 bits of the information about the basic CORESET may indicate information about configuring the frequency domain of the basic CORESET, and the remaining 4 bits may indicate information about the symbols used to monitor the basic CORESET.

[0022] On the other hand, the 8 bits constituting the information about the basic CORESET can be identified as different information by each of the first UE and the second UE.

[0023] On the other hand, the communication module can receive information from the base station indicating the first resource for the first UE.

[0024] On the other hand, some of the random access preamble sequences available in the cell provided by the base station can be used for the first UE, and the remaining random access preamble sequences can be used for the second UE.

[0025] On the other hand, the communication module can obtain information about the CORESET for the first UE based on the information about the basic CORESET.

[0026] On the other hand, in the basic CORESET, a first PDCCH candidate for the first UE can be defined separately from a second PDCCH candidate for the second UE, and the communication module can be configured to monitor the first PDCCH candidate in the basic CORESET.

[0027] According to another aspect of this disclosure, a method of operating a first UE (reduced capability UE) with reduced performance in a wireless communication system is provided. The method may include: receiving configuration information for configuring a first downlink bandwidth portion (DL BWP) and a first uplink bandwidth portion (Uplink BWP) used in an initial access procedure; receiving an indicator indicating BWP access prohibition for the first UE in a second UL BWP and a second DL BWP for a second UE of conventional type; and performing the initial access procedure via at least one of the first DL BWP, the first UL BWP, the second DL BWP, and the second UL BWP based on the indicator. Here, each of the first ULBWP and the second UL BWP can be configured individually, the initial access procedure may include a random access procedure, the first ULBWP may include a first resource for the random access procedure of the first UE, and the first resource may be the same as a second resource for the random access procedure on the second UL BWP of the second UE.

[0028] In one aspect, the method may further include obtaining information about the basic control resource set (CORESET) from a second synchronization signal block (SSB) associated with the second UE.

[0029] In another aspect, the method may further include receiving information about a CORESET for the first UE via a system information block (System Information Block 1 (SIB1)), wherein the CORESET for the first UE and the CORESET for the second UE are defined separately.

[0030] In another aspect, the method may further include receiving SIB1 for the second UE, wherein the SIB1 includes scheduling information about system information for performing the initial access procedure of the first UE.

[0031] On the other hand, the scheduling information may include information about the starting physical resource block (PRB) of the first DL BWP activated for performing the initial access procedure of the first UE.

[0032] In another aspect, the method may further include receiving SIB1 for the second UE, wherein the SIB1 includes configuration information for a random access procedure for initial access of the first UE.

[0033] On the other hand, information about the CORESET for the first UE can be obtained via a first SSB defined separately from the second SSB for the second UE.

[0034] Beneficial effects

[0035] According to embodiments of this disclosure, the RedCap UE can smoothly perform initial cell access, perform random access procedures without conflicting with existing legacy UE types, and perform communication based on various frequency hopping designs.

[0036] The effects that can be obtained in this disclosure are not limited to those described above, and other effects not mentioned can be clearly understood by those skilled in the art from the following description. Attached Figure Description

[0037] Figure 1 This diagram illustrates an example of a wireless frame structure used in a wireless communication system.

[0038] Figure 2 This diagram illustrates an example of a downlink (DL) / uplink (UL) timeslot structure in a wireless communication system.

[0039] 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.

[0040] Figure 4 illustrates the SS / PBCH block used for initial cell access in a 3GPP NR system.

[0041] Figure 5 illustrates the process of transmitting control information and control channels in a 3GPP NR system.

[0042] Figure 6 The diagram shows a control resource set (CORESET) in a 3GPP NR system that can transmit the Physical Downlink Control Channel (PUCCH).

[0043] Figure 7 The diagram illustrates a method for configuring the PDCCH search space in a 3GPP NR system.

[0044] Figure 8 This is a conceptual diagram illustrating carrier aggregation.

[0045] Figure 9 This is a diagram used to illustrate single-carrier communication and multi-carrier communication.

[0046] Figure 10 This is a diagram illustrating an example of the application of cross-carrier scheduling technology.

[0047] 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.

[0048] Figure 12 The diagram illustrates the initial access method based on the example.

[0049] Figure 13 This is a diagram illustrating an initial cell access method according to an embodiment of the present disclosure.

[0050] Figure 14 This is a diagram illustrating an initial cell access method and PRACH resource configuration according to an embodiment of the present disclosure.

[0051] Figure 15 This is a diagram illustrating an initial cell access method and PRACH resource configuration according to another embodiment of the present disclosure.

[0052] Figure 16 This is a diagram illustrating an initial cell access method and PRACH resource configuration according to another embodiment of the present disclosure.

[0053] Figure 17 This is a diagram illustrating an initial cell access method according to another embodiment of the present disclosure.

[0054] Figure 18 This is a diagram illustrating an initial cell access method according to another embodiment of the present disclosure.

[0055] Figure 19 This is a diagram illustrating an initial cell access method according to another embodiment of the present disclosure.

[0056] Figure 20 This is a diagram illustrating an initial cell access method according to another embodiment of the present disclosure.

[0057] Figure 21 This is a diagram illustrating an initial cell access method according to another embodiment of the present disclosure.

[0058] Figure 22 A diagram illustrating a PRACH resource configuration according to another embodiment of the present disclosure is shown.

[0059] Figure 23 A diagram illustrating the scheduling of the physical uplink shared channel in the time domain is shown.

[0060] Figure 24 A diagram illustrating the scheduling of the physical uplink shared channel in the frequency domain is shown.

[0061] Figure 25 A diagram illustrating repeated transmissions of a physical uplink shared channel according to an example is shown.

[0062] Figure 26 This is a diagram illustrating the scheduling of the physical uplink control channel.

[0063] Figure 27 This is a diagram illustrating the repeated transmission of the physical uplink control channel.

[0064] Figure 28 This is a diagram illustrating frequency hopping.

[0065] Figure 29 This is a diagram illustrating broadband frequency hopping.

[0066] Figure 30 This is a diagram illustrating broadband frequency hopping according to an embodiment of the present disclosure.

[0067] Figure 31 This is a diagram illustrating broadband frequency hopping according to another embodiment of the present disclosure.

[0068] Figure 32 This is a diagram illustrating broadband frequency hopping according to another embodiment of the present disclosure.

[0069] Figure 33 This is a diagram illustrating broadband frequency hopping according to an embodiment of the present disclosure.

[0070] Figure 34 The illustration is based on the example of PUSCH repeating type B.

[0071] Figure 35 A diagram illustrating the arrangement of gap symbols in a front nominal repeat of type BPUSH according to an embodiment of the present disclosure is shown.

[0072] Figure 36 A diagram illustrating gap symbols arranged in subsequent nominal repetitions of type BPUSHCH repetitions according to an embodiment of the present disclosure is shown.

[0073] Figure 37 This is a diagram illustrating that, according to an embodiment of the present disclosure, gap symbols are dispersedly arranged in a repeat of type B PUSCH.

[0074] Figure 38 A diagram illustrating gap symbols arranged in a nominal repeat of type BPUSHCH with a large number of symbols is shown, according to an embodiment of the present disclosure.

[0075] Figure 39 A diagram illustrating gap symbols arranged in a nominal repeat of type BPUSHCH with a small number of symbols, according to an embodiment of the present disclosure, is shown.

[0076] Figure 40 A diagram illustrating the arrangement of gap symbols according to an embodiment of the present disclosure is shown, such that isolated symbols do not appear in type B PUSCH repetitions.

[0077] Figure 41 A diagram illustrating the addition of a gap symbol after the nominal repetition in a type B PUSCH repeat according to an embodiment of the present disclosure is shown; and

[0078] Figure 42A diagram illustrating the gap symbols of invalid UL symbols and isolated symbols in a contemplated type B PUSCH repetition according to an embodiment of this disclosure is shown. Detailed Implementation

[0079] The terminology used in this specification adopts, as far as possible, commonly used terms that are currently widely used, taking into account the functions of this disclosure. 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 disclosure. 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.

[0080] 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.

[0081] 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; however, the technical concepts of this disclosure are not limited thereto.

[0082] Unless otherwise specified herein, a base station may include a next-generation node B (gNB) as defined in 3GPP NR. Furthermore, unless otherwise specified, a terminal may include a user equipment (UE).

[0083] Figure 1 This diagram illustrates an example of a wireless frame structure used in a wireless communication system. (Reference) 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*10 3 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).

[0084] Figure 2 This diagram illustrates an example of a downlink (DL) / uplink (UL) timeslot structure in a wireless communication system. Specifically, Figure 2 This illustrates the structure of the resource grid in a 3GPP NR system. Each antenna port has one resource grid. (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. N size,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.

[0085] 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).

[0086] 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.

[0087] 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.

[0088] Each symbol of a radio frame used in time division duplex (TDD) or unpaired spectrum can be configured with at least one of DL symbols, UL symbols, and flexible symbols. A radio frame used as a DL carrier in frequency division duplex (FDD) or paired spectrum can be configured with DL symbols or flexible symbols, while a radio frame used as an UL carrier can be configured with UL symbols or flexible symbols. In a DL symbol, DL transmission is possible, but UL transmission is not possible. In an UL symbol, UL transmission is possible, but DL transmission is not possible. A flexible symbol can be determined to be used as DL or UL according to a signal.

[0089] Information about the type of each symbol, i.e., information indicating any one of DL symbols, UL symbols, and flexible symbols, can be configured with a cell-specific or common radio resource control (RRC) signal. In addition, information about the type of each symbol can be additionally configured with a UE-specific or dedicated RRC signal. The base station notifies, by using a cell-specific RRC signal, i) the period of the cell-specific slot configuration, ii) the number of slots having only DL symbols from the beginning of the period of the cell-specific slot configuration, iii) the number of DL symbols from the first symbol of the slot immediately following the slot having only DL symbols, iv) the number of slots having only UL symbols from the end of the period of the cell-specific slot configuration, and v) the number of UL symbols from the last symbol of the slot immediately preceding the slot having only UL symbols. Here, a symbol not configured with any of UL symbols and DL symbols is a flexible symbol.

[0090] When the information about symbol type is configured with a UE-specific RRC signal, the base station can signal with a cell-specific RRC signal whether the flexible symbol is a DL symbol or an UL symbol. In this case, the UE-specific RRC signal cannot change a DL symbol or an UL symbol configured with a cell-specific RRC signal into another symbol type. The UE-specific RRC signal can signal the number of DL symbols among the N slot symb symbols of the corresponding slot of each slot and the number of UL symbols among the N slot symb symbols of the corresponding slot. In this case, the DL symbols of a slot can be continuously configured from the first symbol to the i-th symbol of the slot. In addition, the UL symbols of a slot can be continuously configured from the j-th symbol to the last symbol of the slot (where i < j). In a slot, a symbol not configured with any of UL symbols and DL symbols is a flexible symbol.

[0091] The type of symbol configured using the above RRC signals can be referred to as a semi-static DL / UL configuration. In the previous semi-static DL / UL configuration configured using RRC signals, flexible symbols can be indicated as DL symbols, UL symbols, or flexible symbols by the dynamic slot format information (SFI) transmitted on the physical DL control channel (PDCCH). In this case, the DL symbol or UL symbol configured using RRC signals will not be changed to another symbol type. Table 1 illustrates the dynamic SFIs that the base station can indicate to the UE.

[0092] [Table 1]

[0093]

[0094] In Table 1, D represents the DL symbol, U represents the UL symbol, and X represents the flexible symbol. As shown in Table 1, a maximum of two DL / UL switchings are allowed in a single time slot.

[0095] Figure 3 This diagram illustrates the physical channels used in 3GPP systems (e.g., NR) and typical signal transmission methods using those physical channels. If the UE is powered on or camped in a new cell, the UE performs an initial cell search (S101). Specifically, the UE can synchronize with the base station (BS) during the initial cell search. To do this, the UE can receive a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) from the base station to synchronize with it and obtain information such as the cell ID. Afterward, the UE is able to receive the physical broadcast channel from the base station and obtain broadcast information within the cell.

[0096] After the initial cell search is completed, the UE receives the physical downlink shared channel (PDSCH) based on 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).

[0097] When a UE initially accesses a base station or does not have radio resources for signal transmission (i.e., a UE 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 response message for the preamble from the base station via the PDCCH and the corresponding PDSCH (S104). 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). Next, the UE waits for the reception of the PDCCH as an indication from the base station for conflict resolution. If the UE successfully receives the PDCCH via the UE's identifier (S106), the random access procedure is terminated.

[0098] 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.

[0099] Figure 4a and Figure 4b The diagram illustrates the SS / PBCH block used for initial cell access in a 3GPP NR system. When power is on or when accessing a new cell, the UE 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).

[0100] refer to Figure 4a and Figure 4bThis 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 4a According 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.

[0101] [Table 2]

[0102]

[0103] SS identification divides a total of 1008 unique physical layer cell IDs into 336 physical layer cell identifier groups through the combination of three PSS and SSS. 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.

[0104] d PSS (n) = 1 - 2x(m)

[0105] m=(n+43N (2) ID )mod 127

[0106] 0≤n<127

[0107] Here, x(i+7) = (x(i+4) + x(i)) mod 2 and is given as

[0108] [x(6) x(5) x(4) x(3) x(2) x(1) x(0)]=[1 1 1 0 1 1 0].

[0109] In addition, the sequence d of SSS SSS (n) is as follows.

[0110] d SSS (n)=[1-2x0((n+m o )mod 127][1-2x i ((n+m1)mod 127]

[0111] m0 = 15 floors (N) (1) ID / 112)+5N (2) ID

[0112] m1 = N (1) ID mod 112

[0113] 0 ≤ n < 127

[0114] here, And was given as

[0115] [x0(6) x0(5) x0(4) x0(3) x0(2) x0(1) x0(0)]=[0 0 0 0 0 0 1]

[0116] [x1(6) x1(5) x1(4) x1(3) x1(2) x1(1) x1(0)]=[0 0 0 0 0 0 1].

[0117] 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.

[0118] 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 compilation) (S204) (S206). Thereafter, the base station can multiplex the DCI based on the PDCCH structure based on Control Channel Elements (CCE) (S208).

[0119] 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 3GPP NR 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.

[0120] Figure 6The diagram illustrates a control resource set (CORESET) in a 3GPP NR system where the Physical Downlink Control Channel (PUCCH) can be transmitted. A CORESET is a time-frequency resource in which the PDCCH (i.e., the control signal 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 within 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.

[0121] Figure 7 The diagram illustrates a method for setting up a PDCCH search space in a 3GPP NR system. Each core may have at least one search space to transmit a PDCCH to a UE. In embodiments of this disclosure, the search space is the set of all time-frequency resources (hereinafter referred to as PDCCH candidates) capable of transmitting a UE's PDCCH. The search space may include a common search space that requires common searching by UEs in 3GPP NR and a UE-specific search space or UE-specific search space that requires searching by a specific UE. In the common search space, a UE may monitor a PDCCH configured to be commonly searched by all UEs belonging to the same base station cell. Furthermore, a UE-specific search space may be set up for each UE, allowing the UE to monitor the PDCCH allocated to each UE at search space locations that vary 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 PDCCHs. Monitoring the PDCCH includes blind decoding of PDCCH candidates within the search space. When blind decoding is successful, it can be expressed as (successfully) detecting / receiving the PDCCH, while when blind decoding fails, it can be expressed as not detecting / receiving or not successfully detecting / receiving the PDCCH.

[0122] 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.

[0123] 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.

[0124] 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".

[0125] Table 3 shows an example of the Physical Uplink Control Channel (PUCCH) used in a wireless communication system.

[0126] [Table 3]

[0127] 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

[0128] PUCCH can be used to send the following UL control information (UCI).

[0129] Scheduling Request (SR): Information used to request UL UL-SCH resources.

[0130] 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 (abbreviated as ACK), negative ACK (hereinafter NACK), 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.

[0131] 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.

[0132] In the 3GPP NR system, five PUCCH formats can be used to support various service scenarios, channel environments, and frame structures.

[0133] PUCCH format 0 is a format capable of delivering 1 or 2 bits of HARQ-ACK information or SR. It can be transmitted via one or two OFDM symbols on the time axis and one PRB on the frequency axis. When transmitting PUCCH format 0 across two OFDM symbols, the same sequence on both symbols can be transmitted via different RBs. This allows the UE to obtain frequency diversity gain. More specifically, the UE can... bit Bit UCI (M) bit =1 or 2) to determine the cyclic shift (CS) value m cs Additionally, this can be achieved by using a predetermined CS value m. cs The cyclic shift sequence is mapped to an OFDM symbol and 12 REs of an RB to transmit a basic sequence of length 12. 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 that differ by 6 in their cyclic shift values. Additionally, when M... bit When = 2, the 2-bit UCI 00, 01, 11 and 10 can be mapped to four cyclic shift sequences that differ by 3 in their cyclic shift values.

[0134] 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.

[0135] 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. This allows the UE to obtain frequency diversity gain. More specifically, for M... bit One 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.

[0136] 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 via 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 π / 2-binary phase shift keying (BPSK) or QPSK to transmit M... bit One 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.

[0137] 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.

[0138] 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.

[0139] 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.

[0140] In 3GPP NR systems, a UE can perform transmission / reception using a bandwidth equal to or less than the bandwidth of a carrier (or cell). For this purpose, a UE can receive a bandwidth portion (BWP) of a continuous bandwidth configured with some carrier bandwidth. A UE operating under TDD or in unpaired spectrum can receive up to four DL / UL BWP pairs on a single carrier (or cell). Additionally, 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 DL carrier (or cell) and up to four UL BWPs on a UL carrier (or cell). A UE can activate one DL BWP and one UL BWP for each carrier (or cell). A UE can choose not to perform reception or transmission on time-frequency resources other than those with activated BWPs. An activated BWP can be referred to as an active BWP.

[0141] 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 BWP to be activated in the DCI used for scheduling PDSCH or PUSCH to change the UE's DL / UL BWP pair. The UE can receive the DCI used for scheduling PDSCH or PUSCH and can identify the DL / UL BWP pair activated based on the BPI. For a DL carrier (or cell) operating in FDD, the base station can include a BPI indicating the BWP to be activated in the DCI used for scheduling PDSCH to change the UE's DL BWP. For a UL carrier (or cell) operating in FDD, the base station can include a BPI indicating the BWP to be activated in the DCI used for scheduling PUSCH to change the UE's UL BWP.

[0142] Figure 8 This is a conceptual diagram illustrating carrier aggregation.

[0143] 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.

[0144] refer to Figure 8As 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.

[0145] 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.

[0146] 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.

[0147] Figure 9 This is a diagram used to illustrate single-carrier communication and multi-carrier communication. Specifically, Figure 9 (a) shows the single-carrier subframe structure and Figure 9 (b) shows the multi-carrier subframe structure.

[0148] 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.

[0149] 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).

[0150] 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.

[0151] 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.

[0152] 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.

[0153] exist Figure 10 In 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.

[0154] 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.

[0155] Figure 11 This is a block diagram illustrating the configuration of a UE and a base station according to embodiments of the present disclosure. In embodiments of the present disclosure, the UE can be implemented using various types of wireless communication devices or computing devices that ensure portability and mobility. The UE can be referred to as a User Equipment (UE), a Station (STA), a Mobile Subscriber (MS), etc. Furthermore, in embodiments of the present 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 a Next Generation Node B (gNB) or an Access Point (AP).

[0156] 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.

[0157] 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.

[0158] 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.

[0159] 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 the sub-6 GHz frequency band supported by the corresponding NIC module.

[0160] 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.

[0161] 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 2.4 GHz or 5 GHz band. 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.

[0162] The memory 130 stores the control program used in the UE 100 and its various data. 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.

[0163] 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.

[0164] 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.

[0165] 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.

[0166] 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.

[0167] 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 120 can include multiple network interface cards, such as cellular communication interface cards 221 and 222 and an unlicensed band communication interface card 223, either internally or externally. In the figures, the communication module 220 is shown as a monolithic integrated module; however, unlike the figures, each network interface card can be arranged independently depending on the circuit configuration or usage.

[0168] Cellular communication interface card 221 can transmit or receive radio signals with at least one of UE 100, external devices, and servers 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 UE 100, external devices, and servers in accordance with cellular communication standards or protocols in a frequency band less than 6 GHz supported by the corresponding NIC module.

[0169] Cellular communication interface card 222 can transmit or receive radio signals with at least one of UE 100, external devices, and servers 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 devices, and servers in accordance with cellular communication standards or protocols in a 6 GHz or higher frequency band supported by the corresponding NIC module.

[0170] The unlicensed 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 band, and provides unlicensed band communication services based on instructions from the processor 210. The unlicensed band communication interface card 223 may include at least one NIC module using an unlicensed band. For example, the unlicensed band may be a 2.4 GHz or 5 GHz band. At least one NIC module of the unlicensed band communication interface card 223 can independently or dependently perform wireless communication with at least one of the UE 100, external devices, and servers in accordance with the unlicensed band communication standards or protocols of the frequency band supported by the corresponding NIC module.

[0171] Figure 11 This 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.

[0172] I. Initial Access Method for RedCap UE

[0173] Figure 12 The illustration shows the initial access method according to the example. In the following text, Rel-15 UE or Rel-16 UE is referred to as a legacy UE, and... Figure 12 It is the general initial access procedure performed by a traditional UE.

[0174] refer to Figure 12The UE receives SSBs from the base station. The frequency and time domains in which SSBs can be transmitted can be defined. The UE can receive SSBs within these frequency and time domains. SSBs include PSS, SSS, and PBCH. The UE can perform downlink synchronization and identify the physical cell ID by receiving PSS and SSS. The UE can receive the Master Information Block (MIB) included in the PBCH by receiving the PBCH.

[0175] The MIB includes the cell's most basic information, as well as configuration information for the Type 0 search space and the basic CORESET (i.e., CORESET0). The UE can monitor and receive the PDCCH based on the Type 0 search space and CORESET0 configuration information. The PDCCH can deliver DCI format 1_0, where the CRC is scrambled with SI-RNTI. DCI format 1_0 can be used for PDSCH scheduling. The PDSCH can deliver SIB1 to the UE, including the cell common information required for the UE to access the cell.

[0176] The UE can receive cell common information and PRACH configuration information from SIB1 delivered by PDSCH. The UE can send PRACH according to the PRACH configuration information. Through PRACH transmission and subsequent random access procedures, the UE can perform uplink synchronization and receive UE-specific information.

[0177] However, the new type of UE (hereinafter referred to as RedCap UE) with reduced capabilities compared to the traditional type of UE may not be able to use it according to Figure 12 The initial cell access procedure is used to access the cell. This is because of the following reasons.

[0178] 1) The bandwidth that a RedCap UE can perform reception may be limited. This is because, in order to keep product prices low, RedCap UEs may only support small bandwidths. On the other hand, in situations such as... Figure 12 The initial cell access process shown does not consider the UE's bandwidth. For example, the bandwidth of CORESET0 (in...) Figure 12 The bandwidth of the UE may be greater than that of the CORESET0 BW.

[0179] 2) RedCap UEs may require higher coverage. This is determined based on the link budget of traditional UE types. Figure 12 The initial cell access process. Therefore, in order for RedCap UEs to successfully perform initial cell access, further improvements are needed based on... Figure 12 The initial cell access process. For example, the PDCCH received in CORESET0 should be sufficient to provide adequate coverage.

[0180] The following examples disclose an improved initial access procedure for this RedCap UE.

[0181] (1) First embodiment

[0182] As a first embodiment of this disclosure, the RedCap UE can receive control channel information for initial cell access for the RedCap UE via SIB1.

[0183] Figure 13 This is a diagram illustrating an initial cell access method according to an embodiment of the present disclosure.

[0184] refer to Figure 13 The RedCap UE can receive the cell's SS / PBCH (or SSB). The RedCap UE can receive CORESET0 frequency domain information via the SS / PBCH (in...). Figure 13 Information in the time domain, shown as CORESET0 BW or Type 0 search space. RedCap UEs can receive PDCCH scrambled with SI-RNTI within the Type 0 search space or CORESET0. RedCap UEs can receive DCI format 1_0 via PDCCH. DCI format 1_0 may include PDSCH for delivering SIB1 (in... Figure 13 The scheduling information (shown as PDSCH for SIB1) is shown in the diagram. Therefore, the RedCap UE can receive SIB1 via PDSCH.

[0185] The RedCap UE can identify the presence or absence of initial cell access information for the RedCap UE in the received SIB1. The initial cell access information for the RedCap UE may include information about the CORESET (hereinafter referred to as CORESET-Red) or search space (hereinafter referred to as search space-Red) for the initial cell access of the RedCap UE.

[0186] RedCap UE can be configured with RedCap UE's CORESET (in Figure 13 The frequency resource allocation information, length, REG, REG bundling, or CCE configuration information (shown as CORESET-Red) is displayed. A RedCap UE can be configured with a search space separate from CORESET0 and corresponding to CORESET-Red. To configure the search space (Search Space-Red), the UE can receive information such as the period and offset for monitoring PDCCHs or the aggregation level of PDCCH candidates and the number of PDCCH candidates per aggregation level.

[0187] If there is no CORESET-Red configuration for the RedCap UE in SIB1 received by the RedCap UE, or if there is no configuration of the search space corresponding to CORESET-Red, the RedCap UE may perform at least one of the following operations.

[0188] The first operation includes the following: if the RedCap UE fails to receive the configuration of CORESET-Red and Search Space-Red via SIB1, it is determined that the RedCap UE cannot access the cell.

[0189] The second operation includes the following: If the RedCap UE fails to receive the configuration of CORESET-Red via SIB1, it is assumed that the frequency resource allocation information, length, REG, REG binding or CCE configuration information of CORESET-Red is the same as the configuration information of CORESET0.

[0190] The third operation includes the following: If the RedCap UE fails to receive some configuration information for CORESET-Red via SIB1, but receives some configuration information for CORESET-Red, then it is assumed that the CORESET-Red configuration information that was not received is the same as the CORESET0 configuration information. For example, if the RedCap UE receives frequency resource allocation information for CORESET-Red via SIB1 but fails to receive length, REG, REG bundle, or CCE configuration information, then it is assumed that the length, REG, REG bundle, and CCE configuration information is the same as the length, REG, REG bundle, or CCE configuration information for CORESET0.

[0191] The fourth operation includes the following: If the RedCap UE fails to receive the configuration of the search space -Red via SIB1, the period and offset or aggregation level of the PDCCH candidates in the search space -Red, as well as the number of PDCCH candidates per aggregation level, are the same as the configuration of the type 0 search space of the cell. Here, the type 0 search space is the search space used to monitor PDCCHs with CRCs scrambled with SI-RNTI.

[0192] The fifth operation includes the following: If the RedCap UE receives some configuration information for search space-Red via SIB1 but fails to receive some of the configuration information for search space-Red, then it is assumed that the configuration information for search space-Red that was not received is the same as the configuration information for type 0 search space. For example, if the RedCap UE receives the period and offset of search space-Red via SIB1 but fails to receive the aggregation level of PDCCH candidates and the number of PDCCH candidates per aggregation level, it can be assumed that the aggregation level of PDCCH candidates and the number of PDCCH candidates per aggregation level are the same as the aggregation level of PDCCH candidates and the number of PDCCH candidates per aggregation level for search space-Red.

[0193] In addition, the RedCap UE can receive an indicator from SIB1 indicating whether the RedCap UE can access the cell.

[0194] As an example, this indicator can indicate whether the RedCap UE can access the cell or not. If the indicator indicates that the RedCap UE cannot access the cell, then the RedCap UE cannot use the PRACH resources received in SIB1 to perform cell access.

[0195] As another example, the indicator can indicate whether the RedCap UE can access the cell using CORESET-Red or Search Space-Red, or whether the RedCap UE cannot access the cell using CORESET-Red or Search Space-Red. If the indicator indicates that the RedCap UE cannot access the cell using CORESET-Red or Search Space-Red, then the RedCap UE can use the PRACH resources received in SIB1 to perform cell access.

[0196] As another example, this indicator can indicate whether the RedCap UE can access the cell via the PRACH configured in SIB1. If the indicator indicates that the RedCap UE can access the cell using the PRACH configured in SIB1, then the RedCap UE can use the PRACH resources received in SIB1 to perform cell access.

[0197] The RedCap UE receives CORESET-Red and Search Space-Red information via SIB1 as follows.

[0198] As a first method, the CORESET-Red and search space-Red information related to the RedCap UE can be configured in the same way as configuring the CORESET0 or Type 0 search space in the PBCH. That is, the CORESET-Red and search space-Red information can be 8 bits. Of these 8 bits, 4 bits can represent the CORESET-Red information, and the remaining 4 bits can represent the search space-Red information. The 4 bits of CORESET-Red information indicate one of 16 combinations. The 4 bits of search space-Red indicate one of 16 combinations. Here, 8 bits are used to provide the description, but if 8 bits are insufficient, they can be extended to any integer number of bits.

[0199] As a second method, the CORESET-Red and search space-Red information related to RedCapUE can be configured in the same way as the existing CORESET and search space.

[0200] As an example, CORESET-Red information may include CORESET-Red frequency information.

[0201] On one hand, CORESET-Red frequency information may include a PRB offset based on CORESET0. That is, CORESET-Red frequency information (assigned PRB) may be a PRB obtained by adding an offset to the PRB of CORESET0.

[0202] On the other hand, CORESET-Red frequency information may include the cell's common PRB index. Here, the cell's common PRB index is the PRB index commonly used by the UEs in the cell, and the frequency corresponding to common PRB index 0 can be received in SIB1. The UE can assign an index from common PRB index 0. CORESET-Red information can indicate the starting index of the PRB by using the common PRB index.

[0203] As another example, the CORESET-Red information may include the length (number of symbols) of CORESET-Red. The length may include 1, 2, or 3 symbols. The length may additionally include 6 to 12 symbols. It may include a value obtained by comparing the length (number of symbols) of CORESET-Red with the length of CORESET0. For example, it may include information indicating whether the length (number of symbols) of CORESET-Red is equal to or different from the length (number of symbols) of CORESET0. The length (number of symbols) of CORESET-Red may be indicated by the difference from the length (number of symbols) of CORESET0. That is, it may include information obtained by subtracting the length (number of symbols) of CORESET0 from the length (number of symbols) of CORESET-Red. Typically, since the length (number of symbols) of CORESET-Red is greater than or equal to the length (number of symbols) of CORESET0, the difference (length (number of symbols) of CORESET-Red - length (number of symbols) of CORESET0) may only include non-negative integers.

[0204] As another example, CORESET-Red information may include information about whether interleaving is performed for the REG-to-CCE mapping. If interleaving is not performed, the REGs (REG bundles) used for the RedCap UE can be sequentially bundled into the CCE. If interleaving is performed, the indices of the REGs (REG bundles) used for the RedCap UE are interleaved, and the interleaved indices can be sequentially bundled into the CCE.

[0205] As another example, CORESET-Red information may include REG bundle size configuration information. The size of a REG bundle indicates the number of REGs included in a REG bundle. REGs can be bundled according to the size of the REG bundle. The RedCap UE can assume that the same precoding is applied to the REGs included in the REG bundle. Therefore, the RedCap UE can reduce channel estimation errors by jointly detecting the DM-RS of REGs included in the REG bundle.

[0206] To improve channel estimation performance, CORESET-Red can include additional information. The RedCap UE can use this additional information to assume that the same precoding is used across different CCEs. Here, different CCEs can be adjacent CCEs in the frequency domain. For example, when the CCE indices are sequentially numbered 0, 1, 2, ... in the frequency domain, the RedCap UE can assume, based on the additional information, that the same precoding is used for adjacent CCEs in the frequency domain, such as CCE0 and CCE1. Additionally, the RedCap UE can assume that the same precoding is used for subsequent CCEs, such as CCE2 and CCE3. Channel estimation performance can be improved by assuming that the same precoding is used for multiple adjacent CCEs in the frequency domain.

[0207] Here, the application of the same precoding can be limited to CCEs included in a single PDCCH candidate. That is, RedCap UE can assume that the same precoding is only used for CCEs included in a single PDCCH candidate. Alternatively, RedCap UE can assume that different precoding is used for CCEs included in different PDCCH candidates.

[0208] As an example, the search space - Red can include period and offset information. The period and offset can include at least one time unit selected from slot units, slot set units, symbol units, and symbol set units. The RedCap UE can additionally use this as an index indicator of the symbol from which PDCCH monitoring begins within each time unit. If the unit of the period and offset information is a slot unit, the index of the starting symbol can be indicated by a 14-bit bitmap. The most significant bit (MSB) of the bitmap indicates the first symbol of the slot, and the least significant bit (LSB) indicates the last symbol of the slot. If the unit of the period and offset information is a time unit other than a slot, a bitmap corresponding to the number of symbols included in the time unit can be indicated. The MSB of the bitmap can indicate the first symbol included in the time unit, and the LSB can indicate the last symbol included in the time unit. The RedCap UE can determine the timing of PDCCH monitoring via the starting index or the period and offset value. The RedCap UE needs to perform blind decoding of the PDCCH in the symbol corresponding to the monitoring timing.

[0209] As another example, the search space -Red can include information about additional surveillance timings during which the PDCCH monitored by the RedCap UE at the surveillance timing can be repeatedly received. The UE can monitor and receive the first PDCCH at a surveillance timing. However, if sufficient reception is not possible using only one first PDCCH, PDCCH reception performance can be improved by repeatedly receiving the first PDCCH at another surveillance timing. Therefore, information about additional surveillance timings that enable repeated reception of the first PDCCH may be required.

[0210] Additional monitoring opportunities can be provided through the following methods.

[0211] As a first method, additional monitoring opportunities can be repeated within each time unit, indicated by the number of time units. Here, the time unit can include at least one of a time slot, a set of time slots, a symbol, and a set of symbols. For example, assume the time unit is a time slot. According to the first method, additional monitoring opportunities can be indicated by the number of time slots (K). In this case, the first PDCCH monitored and received by the RedCap UE during the monitoring opportunity in the first time slot can be repeatedly received in subsequent time slots at the same symbol start position as the symbol start position of the first time slot. The RedCap UE can receive the PDCCH in this way as many times as the indicated number of time slots (K). The same scheme can be used even in the case of time units other than time slots.

[0212] As a second method, additional monitoring opportunities can be repeated in the symbols immediately following the initial monitoring opportunity, and can be indicated by the number of repetitions (K). For example, if it is assumed that a monitoring opportunity is configured in one time slot, the additional monitoring opportunity can be located in the symbol immediately following the symbol where the monitoring opportunity ends in one time slot. Furthermore, another additional monitoring opportunity can be located in the symbol immediately following the symbol where the additional monitoring opportunity ends. In this way, additional monitoring opportunities can be continuously located according to the number of repetitions (K).

[0213] Again in Figure 13In this context, a RedCap UE that has already received information from CORESET-Red or Search Space-Red from SIB1 can receive PDCCH within CORESET-Red and Search Space-Red. PDCCH can be used for PDSCH scheduling. PDSCH can carry SIB1 (hereinafter referred to as SIB1-Red), which includes system information to be additionally received by the RedCap UE. Therefore, the RedCap UE can receive PDCCH based on the information from CORESET-Red or Search Space-Red, and can receive PDSCH scheduled by the PDCCH, thereby receiving SIB1-Red, which is the system information required for initial cell access for the RedCap UE. SIB1-Red may include information about PRACH used for cell access by the RedCap UE. For convenience, the PRACH used by the RedCap UE for cell access can be referred to as PRACH-Red.

[0214] To receive SIB1-Red, the RedCap UE should be informed via PDCCH of the time-frequency resources on which PDSCH has been scheduled. To be scheduled with frequency resources (i.e., PRB), the RedCap UE needs to identify the active downlink BWP. Alternatively, the RedCap UE needs to configure the active downlink BWP. The relevant methods are as follows.

[0215] As a first approach, the RedCap UE may not be configured with a separate active downlink BWP from SIB1. Additionally, based on the CORESET-Red indicated by SIB1, the frequencies from the lowest to the highest frequency PRB may not be determined as the active downlink BWP for the RedCap UE.

[0216] As a second method, the UE can be configured with an active downlink BWP from the SIB1 RedCap UE. Here, the active downlink BWP includes the CORESET-Red band.

[0217] In the above description, SS / PBCH, CORESET0, CORESET-Red, etc., are downlink signals or channels. Therefore, downlink signals or channels can be included in the downlink BWP of a downlink cell. On the other hand, PRACH or PRACH-Red are uplink channels, and therefore can be included in the uplink BWP of an uplink cell. Therefore, in addition to the information of CORESET-Red and search space-Red, time-frequency domain information for PRACH-Red transmission may also be additionally required.

[0218] PRACH can have different subcarrier spacings. For example, PRACH can have smaller subcarrier spacings to allow for longer symbol lengths. 15kHz, 30kHz, 60kHz, or 120kHz are used for the subcarrier spacing of PUSCH and PUCCH to transmit uplink data or control information, while the subcarrier spacing of PRACH can be 1.25kHz or 5kHz. Therefore, signals or channels with different subcarrier spacings can coexist in the uplink cell. In this case, guard bands are needed to suppress interference between signals or channels with adjacent subcarrier spacings. Therefore, if PRACH is scattered across time and frequency resources, uplink resources may be wasted due to guard bands. To prevent this, PRACH used by traditional UEs and PRACH used by RedCap UEs need to be placed in time and frequency resources as close as possible.

[0219] In the following embodiment, a method is disclosed for placing the PRACH of a conventional type UE and the PRACH-Red of a RedCap UE in adjacent time-frequency resources in an uplink cell.

[0220] refer to Figure 14 Describe the first method, refer to Figure 15 Describe the second method, and refer to Figure 16 Describe the third method.

[0221] Figure 14 This is a diagram illustrating an initial cell access method and PRACH resource configuration according to an embodiment of the present disclosure.

[0222] refer to Figure 14 RedCap UE can determine that PRACH-Red is located at a time adjacent to the PRACH of a traditional type UE (see [link]). Figure 14 (TDM shown). A separate configuration for PRACH-Red frequency information may not exist. In this case, the frequency information for PRACH-Red can be the same as the frequency information for PRACH. That is, the frequency occupied by PRACH and the frequency occupied by PRACH-Red can be the same. RedCap UEs can be configured with separate time information for PRACH-Red.

[0223] Here, the timing information may include whether PRACH-Red immediately precedes or follows PRACH. If it immediately follows PRACH, PRACH-Red can begin at a time point immediately following the end of PRACH (or in a subsequent time slot). If it immediately precedes PRACH, PRACH-Red can end at a time point immediately preceding the start of PRACH (or in a subsequent time slot).

[0224] Alternatively, the time information may indicate the time difference between PRACH and PRACH-Red. More specifically, the time information may include the time difference or interval (number of symbols or number of time slots) between the last time point of PRACH and the first time point of PRACH-Red. Alternatively, the time information may include the time difference or interval (number of symbols or number of time slots) between the last time point of PRACH-Red and the first time point of PRACH. Alternatively, the time information may include the time difference or interval (number of symbols or number of time slots) between the first time point of PRACH and the first time point of PRACH-Red.

[0225] Figure 15 This is a diagram illustrating an initial cell access method and PRACH resource configuration according to another embodiment of the present disclosure.

[0226] refer to Figure 15 A RedCap UE can determine that PRACH-Red is located on a frequency adjacent to the PRACH of a legacy UE. A separate configuration for PRACH-Red timing information may not be required. In this case, the timing information for PRACH-Red can be the same as the timing information for PRACH. That is, the time (slots and symbols) occupied by PRACH and the time (slots and symbols) occupied by PRACH-Red can be the same. A RedCap UE can be configured with separate frequency information for PRACH-Red.

[0227] Here, frequency information may include information about whether the frequency of PRACH-Red is immediately below or above PRACH.

[0228] Alternatively, frequency information may indicate the frequency difference between PRACH and PRACH-Red. More specifically, frequency information may include the frequency difference or interval between the highest frequency of PRACH and the lowest frequency of PRACH-Red (based on the number of subcarriers per unit of the uplink BWP of the uplink cell, or the number of subcarriers per unit of the PRACH subcarrier interval, or the number of PRBs). Alternatively, frequency information may include the frequency difference or interval between the highest frequency of PRACH-Red and the lowest frequency of PRACH (based on the number of subcarriers per unit of the uplink BWP of the uplink cell, or the number of subcarriers per unit of the PRACH subcarrier interval, or the number of PRBs). Alternatively, frequency information may include the frequency difference or interval between the lowest frequency of PRACH and the lowest frequency of PRACH-Red (based on the number of subcarriers per unit of the uplink BWP of the uplink cell, or the number of subcarriers per unit of the PRACH subcarrier interval, or the number of PRBs).

[0229] Figure 16 This is a diagram illustrating an initial cell access method and PRACH resource configuration according to another embodiment of the present disclosure.

[0230] refer to Figure 16 The RedCap UE can determine that PRACH-Red is located at the same time-frequency as the PRACH of a legacy UE. A separate configuration for the time-frequency information of PRACH-Red may not be required. In this case, the time-frequency information of PRACH-Red can be the same as the time-frequency information of PRACH. The RedCap UE can use some of the PRACHs at that time-frequency. For example, the PRACH of a legacy UE may include multiple PRACH preamble sequences. In this case, the RedCap UE can use some of the multiple PRACH preamble sequences.

[0231] For this purpose, the RedCap UE can be configured with the index (or ID) of the available sequences in the PRACH leading sequence. More specifically, the RedCap UE can be configured with the lowest index (or ID) among the indexes (or IDs) of the available sequences, and can use sequences with that index (to ID) and the indices (to ID) that follow that index (to ID).

[0232] As another example, RedCap UE can be configured with the number of available sequences, and can use as many sequences with high indices (or IDs) as the number of available sequences.

[0233] (2) Second embodiment

[0234] According to a second embodiment of this disclosure, the RedCap UE can receive scheduling information for initial cell access system information for the RedCap UE in SIB1. Here, the system information for initial cell access for the RedCap UE is referred to as SIB1-Red. This is in Figure 17 As shown in the image.

[0235] Figure 17 This is a diagram illustrating an initial cell access method according to another embodiment of the present disclosure.

[0236] refer to Figure 17 The RedCap UE can receive the cell's SS / PBCH (or SSB). The RedCap UE can receive frequency domain information for CORESET0 or time domain information for the Type 0 search space via the SS / PBCH. The RedCap UE can receive PDCCH scrambled with SI-RNTI in the Type 0 search space or CORESET0. The RedCap UE can receive DCI format 1_0 via the PDCCH. DCI format 1_0 may include scheduling information for delivering SIB1 PDSCH. Therefore, the RedCap UE can receive SIB1 (in...) Figure 17 The image shows a PDSCH for SIB1.

[0237] The SIB1 received by the RedCap UE may include cell access information for legacy UEs. Legacy UEs do not require separate system information for RedCap UEs. Therefore, adding system information for RedCap UEs to the existing SIB1 may increase the overhead of SIB1. To prevent this, it is preferable to transmit the system information required by the RedCap UE separately. Therefore, SIB1 may include time-frequency information of the PDSCH on which the system information required by the RedCap UE can be received. The RedCap UE can receive the PDSCH according to the time-frequency information. The received PDSCH may include SIB1-Red (in... Figure 17 The diagram shows the PDSCH used for SIB1-Red. The RedCap UE can receive information for initial cell access by receiving SIB1-Red. For example, the RedCap UE can identify the configuration of PRACH-Red for initial cell access based on SIB1-Red.

[0238] In order to allocate frequency resources (i.e., PRBs) for PDSCH scheduled on a RedCap UE for SIB1-Red, the UE needs to identify the active downlink BWP (in) on which PDSCH is scheduled. Figure 17(This is shown as RedCap BW). Therefore, RedCapUE needs to be configured with an active downlink BWP.

[0239] As an example, a RedCap UE can be configured with the length of the active downlink BWP from SIB1 and an index of the starting PRB (the PRB with the lowest frequency). Here, the PRB index can be indicated by a common PRB index. Alternatively, the PRB index can be indicated by a frequency interval (the number of PRBs) starting from CORESET0. That is, since the RedCap UE has already identified the frequency domain occupied by CORESET0, the starting PRB of the active downlink BWP can be determined by adding a given frequency interval (the number of PRBs) to that frequency domain.

[0240] At least one of the following values—24 PRBs, 48 ​​PRBs, and 96 PRBs—can be configured as the length. As another example, the length can be equal to the number of PRBs included in CORESET0. In this case, information regarding the length of the active downlink BWP can be omitted in SIB1.

[0241] RedCap UEs can assume that they receive PDSCHs delivering SIB1-Red within the configured active downlink BWP.

[0242] (3) Third embodiment

[0243] According to a third embodiment of this disclosure, the RedCap UE can receive PRACH configuration information for initial cell access in SIB1. Here, the PRACH for initial cell access of the RedCap UE is referred to as PRACH-Red. This is in Figure 18 As shown in the image.

[0244] Figure 18 This is a diagram illustrating an initial cell access method according to another embodiment of the present disclosure.

[0245] refer to Figure 18 The RedCap UE can receive the cell's SS / PBCH (or SSB). The RedCap UE can receive frequency domain information for CORESET0 or time domain information for the Type 0 search space via the SS / PBCH. The RedCap UE can receive PDCCH scrambled with SI-RNTI in the Type 0 search space or CORESET0. The RedCap UE can receive DCI format 1_0 via the PDCCH. DCI format 1_0 may include PDSCH scheduling information for SIB1. Therefore, the RedCap UE can receive SIB1 (in... Figure 18 The image shows a PDSCH for SIB1.

[0246] The SIB1 received by the RedCap UE may include cell access information for legacy UEs. Additionally, the SIB1 may include system information for the RedCap UE. Therefore, the RedCap UE can obtain initial cell access information about itself via the SIB1 without needing to receive separate system information (e.g., ...). Figure 17 (SIB1-Red in the original text). For example, SIB1 may include PRACH-Red configuration information for initial cell access.

[0247] RedCap UEs can be configured with an uplink BWP for configuring PRACH-Red and cell access. PRACH-Red can be transmitted within the uplink BWP. Therefore, PRACH-Red configuration is included in the uplink BWP. The uplink BWP for RedCap UEs in SIB1 can be configured as follows.

[0248] (4) Fourth embodiment

[0249] According to a fourth embodiment of this disclosure, a RedCap UE can receive an SS / PBCH intended solely for RedCap UEs. This distinguishes it from an SS / PBCH received by a legacy type UE. The method of differentiation will be described later. For convenience, an SS / PBCH that can be received solely by a RedCap UE is referred to as SSB-Red. This is in Figure 19 As shown in the image.

[0250] Figure 19 This is a diagram illustrating an initial cell access method according to another embodiment of the present disclosure.

[0251] refer to Figure 19 RedCap UE can be used in BWPs that are only for RedCap UE (in Figure 19 In the RedCap BW (shown in the image), the RedCap UE receives SSB-Red, which is an SS / PBCH used only by the RedCap UE. By receiving SSB-Red, the RedCap UE can obtain downlink signal synchronization and receive the cell ID and Master Information Block (MIB) transmitted in the PBCH. By receiving SSB-Red, the RedCap UE can obtain configuration information for CORESET-Red or Search Space-Red, in which it will monitor the PDCCH used to schedule the delivery of SIB1-Red. The RedCap UE can monitor and receive the PDCCH in CORESET-Red or Search Space-Red. By receiving the PDCCH, the RedCap UE can receive the PDSCH for delivering SIB1-Red (in the image). Figure 19 (The diagram shows the PDSCH used for SIB1-Red). The RedCap UE can be configured with PRACH-Red configuration information for cell access from SIB1-Red, and can send PRACH according to the PRACH-Red configuration information.

[0252] In the fourth embodiment, the RedCap UE needs to receive SSB-Red in a separate BWP, different from the downlink BWP of a legacy UE. However, since SSB-Red is received before cell access, the RedCap UE cannot identify the frequency and time at which SSB-Red is transmitted. Furthermore, the RedCap UE should be able to distinguish between the SS / PBCH and SSB-Red received by a legacy UE. A method for this is disclosed below.

[0253] The first method includes a procedure in which the RedCap UE performs the initial cell access procedure like a conventional UE. For example, the RedCap UE can receive the cell's SS / PBCH (or SSB). The RedCap UE can receive frequency domain information of CORESET0 or time domain information of the Type 0 search space via the SS / PBCH. The RedCap UE can receive a PDCCH scrambled with SI-RNTI using the information of the Type 0 search space or CORESET0. The RedCap UE can receive DCI format 1_0 via the PDCCH. DCI format 1_0 can include scheduling information for delivering the PDSCH of SIB1. Therefore, the RedCap UE can receive SIB1. SIB1 can include information on the frequency and time for transmitting SSB-Red. That is, the UE can be configured via SIB1 to receive SSB-Red information for the RedCap UE.

[0254] The frequency of SSB-Red can be indicated using the Absolute Radio Channel Number (ARFCN). Alternatively, the frequency of SSB-Red can be indicated by the Common PRB Index. Alternatively, the frequency of SSB-Red can be indicated by the interval from the frequency of the SSB. Here, the interval can be indicated as a frequency. The interval can be indicated by the number of PRBs. The interval can be indicated by the number of subcarriers. The interval can be indicated by the number of channel grids or synchronization grids between the SSB and SSB-Red.

[0255] The timing of SSB-Red can be the same as that of SSB. That is, SSB and SSB-Red can be transmitted at the same time (slot and symbol). As another example, the timing of SSB-Red and SSB can have a certain time interval. For example, a certain time interval can be given as 5ms (half a frame length). With the predetermined time interval between SSB and SSB-Red, the RedCap UE can receive SSB in the first time interval and SSB-Red in the second time interval. In this way, two synchronization blocks are received, and therefore downlink synchronization can be performed more accurately.

[0256] The second method includes SSB-Red, which has a structure different from that of traditional UE types.

[0257] As an example, SSB-Red can be designed to include a larger frequency band to improve PBCH reception performance. For instance, SSB-Red can be designed to have four more PRBs than the SSB of a conventional type of UE. That is, SSB-Red can be designed to occupy 24 PRBs. More specifically, SSB-Red can have four symbols. In these four symbols, PSS is transmitted in the first symbol and SSS is transmitted in the third symbol. Additionally, PBCH can be transmitted in the 24 PRBs of the second symbol, the 24 PRBs of the fourth symbol, and the 24 PRBs of the third symbol, excluding the resources mapped to the SSS. Although the example of 24 PRBs has been described above, it can be extended to more PRBs.

[0258] RedCap UEs can receive PSS and SSS to obtain downlink signal synchronization and cell ID. To determine between an SS / PBCH (SSB) containing 20 PRBs and an SS / PBCH designed to have more PRBs (SSB-Red), the RedCap UE can perform PBCH decoding by assuming it has 20 PRBs, and by assuming it is designed to have more PRBs. If PBCH decoding succeeds by assuming 20 PRBs, the UE can identify the SS / PBCH as a normal UE (legacy) SSB. If PBCH decoding succeeds by assuming more PRBs, the RedCap UE can identify the SS / PBCH as a RedCap SSB-Red.

[0259] As another example, SSB-Red can be designed to include more symbols to improve PBCH reception performance. For instance, SSB-Red can be designed to have one or two more symbols than a conventional type of UE. That is, SSB-Red can be designed to include 5 to 6 symbols. The PSS is transmitted in the first symbol and the SSS is transmitted in the third symbol. Additionally, the PBCH can be transmitted in the second and fourth symbols, and in the fifth or sixth symbol.

[0260] RedCap UEs can receive PSS and SSS to obtain downlink signal synchronization and cell ID. To determine between an SS / PBCH (SSB) containing four symbols and a PBCH designed to have more symbols (SSB-Red), the RedCap UE can perform PBCH decoding by assuming it has four symbols, and by assuming it is designed to have more symbols. If PBCH decoding is successful by assuming it has four symbols, the UE can identify the SS / PBCH as the SSB of a normal UE (legacy). If PBCH decoding is successful by assuming it has more symbols, the RedCap UE can identify the SS / PBCH as the RedCap SSB-Red.

[0261] As another example, SSB and SSB-Red can be distinguished based on the symbol sequence to which the SS / PBCH is mapped. For instance, in SSB-Red, unlike in SSB, the PSS is located in the first symbol, and the position of the SSS can be moved to the second or fourth symbol. If the SSS is moved to the second symbol, the PBCH can be sent in the PRBs not occupied by the SSS among the 20 PRBs of the third symbol, the 20 PRBs of the fourth symbol, and the 20 PRBs of the second symbol. If the SSS is moved to the fourth symbol, the PBCH can be sent in the PRBs not occupied by the SSS among the 20 PRBs of the second symbol, the 20 PRBs of the third symbol, and the 20 PRBs of the fourth symbol.

[0262] RedCap UEs can receive PSS. Additionally, RedCap UEs can determine the symbol from which the SSS is transmitted to identify whether the SSB is the SSB of a legacy UE or the SSB-Red of a RedCap UE. If the SSS is received in the third symbol, the UE can identify the SS / PBCH as the SSB of a normal (legacy) UE. If the SSS is received in the second or fourth symbol, the UE can identify the SS / PBCH as the SSB-Red of a RedCap UE.

[0263] As another example, the physical cell ID obtained from the SS / PBCH can be used to distinguish between SSB and SSB-Red. For example, the SS / PBCH can have up to 1008 physical cell IDs. The RedCap UE can determine SSB-Red based on a specific value among these up to 1008 physical cell IDs. For example, the specific value could be a physical cell ID that leaves a remainder of 0 when divided by 3. As another example, since the physical cell ID has N... cell ID =3*N (1) ID +N (2) ID In the form of N, therefore if N (1) ID or N (2) ID If the value is specific, then SSB-Red can be determined. As another example, the number of physical cell IDs available for the SS / PBCH can be increased to 1008 or more. In this case, if the physical cell ID has a value of 1008 or greater, the RedCap UE can determine that the SS / PBCH is SSB-Red.

[0264] As another example, SSB and SSB-Red can be distinguished based on the RE mapping sequence of the PBCH in the SS / PBCH. For instance, if the PBCH of a legacy UE's SSB is mapped in a first direction (e.g., with a sequence from low-frequency REs to high-frequency REs), then the PBCH of a RedCap UE's SSB-Red can be mapped in a second direction (e.g., the opposite direction, where the mapping is performed with a sequence from high-frequency REs to low-frequency REs). Here, the second direction can be different from the first direction. The UE can determine whether the corresponding SSB is a legacy UE's SSB or a RedCap UE's SSB-Red based on the RE mapping of the PBCH.

[0265] RedCap UEs can receive PSS and SSS to obtain downlink signal synchronization and cell ID. To determine between the SS / PBCH (SSB) mapped in the first direction and the PBCH designed for the second direction (SSB-Red), the RedCap UE can perform PBCH decoding by assuming the first direction and by assuming it is designed for the second direction. If PBCH decoding is successful by assuming the first direction, the UE can identify the SS / PBCH as the SSB of a normal UE (legacy). If PBCH decoding is successful by assuming the second direction, the UE can identify the SS / PBCH as the RedCap SSB-Red.

[0266] As another example, SSB and SSB-Red can be distinguished based on the CRC of the PBCH in the SS / PBCH. For instance, if the PBCH of an SSB in a legacy UE is scrambled with a first CRC, then the PBCH of an SSB-Red in a RedCap UE can be scrambled with a second CRC, different from the first CRC. The UE can determine whether the corresponding SSB is an SSB of a legacy UE or an SSB-Red of a RedCap UE by identifying the CRC value of the PBCH.

[0267] RedCap UEs can receive PSS and SSS to obtain downlink signal synchronization and cell ID. To determine between an SS / PBCH scrambled with a first CRC (SSB) and a PBCH scrambled with a second CRC (SSB-Red), the RedCap UE can perform PBCH decoding by assuming the first CRC and by assuming the second CRC. If PBCH decoding is successful by assuming the first CRC, the UE can identify the SS / PBCH as the SSB of a legacy UE. If PBCH decoding is successful by assuming the second CRC, the UE can identify the SS / PBCH as the RedCap SSB-Red.

[0268] As another example, SSB and SSB-Red can be distinguished based on one bit of the PBCH in the SS / PBCH. The PBCH of a legacy type UE's SSB can have one unused bit. Therefore, the value of this one bit can be used to determine whether it is a legacy type UE's SSB or a RedCap UE's SSB-Red. For example, if the value of the one bit in the PBCH is "0", the RedCap UE can identify the corresponding SSB as a legacy type UE's SSB, and if the value is "1", the corresponding SSB can be identified as a RedCap UE's SSB-Red.

[0269] In the previous example, the RedCap UE could determine between the SSB of a traditional UE or the SSB-Red of a RedCap UE only after receiving the PSS, SSS, and PBCH. This could result in additional reception overhead and battery consumption.

[0270] As another example, the frequency at which SSB-Red can be transmitted can be different from the frequency at which SSBs are transmitted. For example, the UE can receive SSBs at a certain frequency interval in order to receive the correct SSB. Here, a certain frequency interval can be defined as a synchronization grid. To reduce the UE's battery consumption, this allows for sparse reception of SSBs at a certain frequency interval (e.g., tens of kHz to hundreds of kHz), rather than receiving SSBs at all frequencies. The base station transmits SSBs at a certain frequency interval so that the UE can receive the SSBs correctly. In other words, there may be frequency bands where the UE does not perform SSB monitoring. The base station can transmit SSB-Red in this frequency band, and the RedCap UE can receive SSB-Red in this frequency band.

[0271] As another example, the time interval for transmitting SSB-Red may differ from the time interval for transmitting SSB. For instance, to receive the correct SSB, the UE may receive the SSB within a 5ms half-frame of a 10ms radio frame. In other words, there may be time intervals during which the UE does not perform SSB monitoring. For example, if the SSB is transmitted within the 5ms half-frame of a 10ms radio frame, SSB monitoring is not performed during the remaining time interval. The base station may transmit SSB-Red during this time interval, and the RedCap UE may receive the SSB-Red during this time interval.

[0272] (5) Fifth Embodiment

[0273] According to the fifth embodiment of this disclosure, a RedCap UE can interpret the information indicated by the SS / PBCH differently than a conventional UE. Here, both conventional and RedCap UEs can receive the SS / PBCH. That is, the structure of the SS / PBCH can be the same as the structure of the SSB in a conventional UE. This is... Figure 20 As shown in the image.

[0274] Figure 20 This is a diagram illustrating an initial cell access method according to another embodiment of the present disclosure.

[0275] refer to Figure 20 Traditional UEs and RedCap UEs can receive the SS / PBCH. By receiving the PSS and SSS, downlink signal synchronization can be obtained, and the physical cell ID can be received. Traditional UEs and RedCap UEs can also receive the PBCH. In this case, traditional UEs and RedCap UEs can interpret the PBCH in different ways.

[0276] Traditional UEs can receive CORESET0 configuration information and Type 0 search space configuration information via 8 bits of the PBCH. The 4 bits representing the frequency configuration information of CORESET0 can indicate one of 16 combinations. The 4 bits representing the configuration information of the Type 0 search space can also indicate one of 16 combinations. If the 4 bits indicate "0000", it indicates the first of the 16 combinations. In this way, via 4 bits and 4 bits (a total of 8 bits), the UE can receive the PDCCH used to schedule the delivery of SIB1 PDSCH.

[0277] The RedCap UE can interpret the 8 bits of the PBCH differently. The 4 bits representing the configuration information for CORESET0 can be reinterpreted for use as the configuration information for CORESET-Red. That is, the configuration information for CORESET-Red is indicated by 4 bits and can indicate one of 16 combinations. The 4 bits representing the configuration information for the type 0 search space can also be reinterpreted for use as the configuration information for search space-Red.

[0278] For example, when the 4-bit indication representing the configuration information of CORESET0 is "0000", the UE operates as follows: If the UE is a legacy type UE, then one of 16 combinations of 4-bit indication representing the configuration information of CORESET0 is determined. That is, if the 4 bits show "0000", then this is determined to be the first combination of 16 combinations representing the configuration information of CORESET0. If the UE is a RedCap UE, then one of 16 combinations of 4-bit indication representing the configuration information of CORESET-Red is determined. That is, if the 4 bits show "0000", then this is determined to be the first combination of 16 combinations representing the configuration information of CORESET-Red.

[0279] This can indicate to the UE whether to perform reinterpretation. For example, 1 bit of the PBCH can be used to indicate to the RedCap UE whether information received in the PBCH can be reinterpreted by the RedCap UE. If the 1 bit is "0", the RedCap UE should not reinterpret the information received in the PBCH. If the 1 bit is "1", the RedCap UE can reinterpret the information received in the PBCH.

[0280] (6) Sixth Embodiment

[0281] According to the sixth embodiment of this disclosure, the RedCap UE can determine the configuration information of CORESET-Red based on CORESET0. More specifically, the RedCap UE can obtain the configuration information of CORESET0 by receiving SS / PBCH. The RedCap UE can infer the configuration information of CORESET-Red based on the configuration information of CORESET0.

[0282] As an example, it can be assumed that CORESET-Red begins in the symbol immediately following the symbol that ends CORESET0. Here, CORESET-Red can have the same configuration as CORESET0. That is, the number of PRBs, the position of the PRBs, or the length of the CORESET can be the same as CORESET0. It can also be assumed that CORESET-Red begins in the time slot immediately following the time slot to which CORESET0 belongs. Here, CORESET-Red can have the same configuration as CORESET0. That is, the number of PRBs, the position of the PRBs, or the length of the CORESET can be the same as CORESET0. The position of the symbol in which CORESET-Red begins within the time slot can be the same as the position in which CORESET0 begins within the time slot. Here, the immediately following symbol or the immediately following time slot is described, but this can be further extended so that symbols following a certain number of symbols or time slots following a certain number of time slots can be applied. Furthermore, it has been described that CORESET-Red is only located after CORESET0, but conversely, CORESET-Red can be located before CORESET0.

[0283] As another example, it can be assumed that CORESET-Red begins in a PRB immediately above the PRB that ends with CORESET0. Here, CORESET-Red can have the same configuration as CORESET0. That is, the number of PRBs or the length of the CORESET can be the same as CORESET0. It has been described that CORESET-Red begins immediately above a PRB, but this can be extended further so that CORESET-Red begins after a certain number of PRBs. CORESET-Red can also be located below the PRB that begins with CORESET0.

[0284] (7) Seventh Embodiment

[0285] In the seventh embodiment of this disclosure, both legacy UEs and RedCap UEs can monitor different PDCCH candidates in CORESET0. Here, CORESET0 is indicated in the SS / PBCH. Legacy UEs and RedCap UEs can receive CORESET0 configuration information equally without distinction. This is in... Figure 21 As shown in the image.

[0286] Figure 21 This is a diagram illustrating an initial cell access method according to another embodiment of the present disclosure.

[0287] refer to Figure 21 Traditional UEs can receive the PDCCH for scheduling SIB1 in CORESET0. This PDCCH can deliver DCI format 1_0.

[0288] RedCap UEs can receive PDCCHs delivering SIB1-Red in CORESET0. These PDCCHs can deliver DCI format X. The method for configuring DCI format X is as follows.

[0289] In the first method, the lengths of DCI format 1_0 and DCI format X can be different from each other. That is, since the conventional type UE performs blind decoding of the first-length DCI format 1_0, the conventional type UE can receive DCI format 1_0 but may not receive DCI format X. Conversely, since the RedCap UE performs blind decoding of the second-length DCI format X, the RedCap UE can receive DCI format X but may not receive DCI format 1_0. The RedCap UE may additionally perform blind decoding of the first-length DCI format 1_0 to receive DCI format 1_0, and may receive SIB1 scheduled by DCI format 1_0.

[0290] In the second method, the CRCs of DCI format 1_0 and DCI format X can be scrambled with different values. For example, the CRC of DCI format 1_0 is scrambled with SI-RNTI, but the CRC of DCI format X can be scrambled with a value different from SI-RNTI. That is, because the conventional type UE performs blind decoding of DCI format 1_0 scrambled with SI-RNTI, the conventional type UE can receive DCI format 1_0 but may not receive DCI format X. Conversely, because the RedCap UE performs blind decoding of DCI format X scrambled with different values, the RedCap UE can receive DCI format X but may not receive DCI format 1_0. The RedCap UE can additionally perform blind decoding of DCI format 1_0 scrambled with SI-RNTI to receive DCI format 1_0, and can receive SIB1 scheduled by DCI format 1_0.

[0291] In the third method, both traditional type UEs and RedCap UEs can receive DCI format 1_0 and DCI format X, and DCI format 1_0 and DCI format X can be distinguished by a 1-bit indicator. This 1-bit indicator can be located in the same position in both DCI format 1_0 and DCI format X. If the 1-bit value is "0", DCI format 1_0 is determined, and if the 1-bit value is "1", DCI format X is determined. Although a 1-bit description has been provided for convenience, DCI format 1_0 and DCI format X can be distinguished by multiple bits, or by a combination of specific code points.

[0292] II. RedCap UE PRACH Configuration and RAR Reception Method

[0293] This embodiment relates to a method for configuring multiple PRACHs during the initial cell access and random access process of a UE and for receiving random access responses (RARs) resulting from the multiple PRACH configurations.

[0294] Typically, the UE can receive a PRACH configuration for random access from the base station via the SIB. For reference, the System Information Block can configure an uplink initial BWP. Here, the initial uplink BWP is the BWP used by the UE during the random access procedure. An uplink initial BWP includes a PRACH configuration.

[0295] The PRACH configuration may include at least one of the following information.

[0296] - The time slot for sending PRACH timing in the time domain

[0297] - The symbol that marks the start of the PRACH timing within the time slot for transmitting PRACH timings in the time domain.

[0298] -PRACH timing is located on a subcarrier in the frequency domain.

[0299] - The number of PRACH opportunities, i.e., the set of PRACH opportunities in the frequency domain.

[0300] - Sequences used by the preamble in the code field

[0301] Here, a PRACH event can include up to 64 leaders. Each leader can be assigned an index of one of 0, 1, ..., 63.

[0302] The base station can configure additional uplink carriers to provide higher coverage to the UE. This is called a supplementary UL carrier (SUL carrier). The base station can also configure a PRACH for the SUL, and the UE can access the uplink cell via the SUL's PRACH. For reference, the SIB can configure an initial uplink BWP for the SUL. Here, the initial uplink BWP is the BWP used by the UE during the random access procedure. A PRACH configuration can be included in an initial uplink BWP.

[0303] In the following, in this disclosure, to distinguish between SUL carriers and normal uplink carriers, a normal uplink carrier is referred to as a normal UL carrier (NUL carrier). Unless otherwise stated, the embodiments disclosed in this disclosure can be applied without NUL / SUL differences.

[0304] If the UE receives both the PRACH configuration on the NUL carrier and the PRACH configuration on the SUL carrier, the UE can perform random access via the PRACH on the NUL carrier and the PRACH on the SUL carrier. In other words, the UE can perform a random access procedure by sending one of the PRACH configurations on the NUL carrier or the SUL carrier to the base station.

[0305] The UE can select a preamble based on PRACH information and send the selected preamble to the base station. The subsequent rough procedure for random access is as follows.

[0306] The UE can monitor the PDCCH transmitted from the base station for a predetermined time after transmitting the preamble. Here, the UE can monitor the PDCCH scrambled with RA-RNTI. Here, the RA-RNTI value is determined based on the preamble transmitted by the UE, and the method for obtaining a specific RA-RNTI value will be described later. When the RA-RNTI-scrambled PDCCH is received, the UE can receive the PDSCH scheduled by the PDCCH. The PDSCH can be the TC-RNTI value and information for scheduling message 3PUSCH. The UE can send message 3PUSCH to the base station according to the scheduling information. The UE can receive the PDCCH for scheduling message 4PDSCH from the base station. Here, the PDCCH can be scrambled with the TC-RNTI value. When the TC-RNTI-scrambled PDCCH is received, the UE can receive message 4PDSCH scheduled by the PDCCH and can send a HARQ-ACK to the base station depending on whether the PDSCH is successfully received.

[0307] The method by which the UE obtains RA-RNTI during the above random access process is as follows.

[0308] [Equation 1]

[0309] RA-RNTI=1+s_id+14×t_id+14×80×f_id+14×80×8×ul_carrier_id

[0310] Wherein, s_id is the index of the first OFDM symbol of the PRACH timing (0≤s_id<14), t_id is the index of the first slot of the PRACH timing in the system frame (0≤t_id<80), f_id is the index of the PRACH timing in the frequency domain (0≤f_id<8), and ul_carrier_id is the index of the uplink carrier used for random access preamble transmission (0 for NUL carriers and 1 for SUL carriers).

[0311] The UE and base station can obtain the RA-RNTI based on Equation 1. If two UEs transmit preambles at different PRACH timings, at least one of the values ​​of s_id, t_id, or f_id will be different for each UE. Therefore, since two UEs that have transmitted preambles at different PRACH timings are monitoring PDCCHs scrambled with different RA-RNTIs, the preambles and their corresponding PDCCHs can be distinguished. Furthermore, even if different UEs have the same s_id, t_id, and f_id, if one UE transmits a preamble on a NUL carrier and another UE transmits a preamble on a SUL carrier, the two UEs can monitor PDCCHs scrambled with different RA-RNTIs based on the ul_carrier_id value. Therefore, the preambles and their corresponding PDCCHs for the two UEs can be distinguished.

[0312] Two UEs with the same RA-RNTI value transmit a preamble during a PRACH event on the same carrier (either NUL or SUL) with the same s_id, t_id, or f_id. In this case, if the preambles transmitted by the two UEs during the PRACH event are different, the preambles can be distinguished based on their IDs. More specifically, since the two UEs have the same RA-RNTI value, they monitor PDCCHs scrambled with the same RA-RNTI value. If both UEs receive a PDCCH scrambled with the same RA-RNTI value, they can receive the PDSCH scheduled by the PDCCH. Here, the PDSCH may include a Random Access Preamble Identifier (RAPID). If the RAPID is the same as the index of the preamble transmitted by the UE itself, the UE can identify that the Random Access Response (RAR) corresponds to the preamble it transmitted. Therefore, two UEs that have transmitted different preambles can be distinguished via the RAPID.

[0313] In this way, each UE can receive the RAR sent to it based on the preamble index and the PRACH timing of the PRACH sent by the UE itself. However, there may be cases where the UE cannot determine the RAR sent to it based on the preamble index and the PRACH timing of the PRACH sent by the UE itself. An embodiment to solve this problem is disclosed below.

[0314] To support new UE types such as RedCap UEs, base stations may additionally configure new PRACH configurations for RedCap UEs. In the following text, for convenience, the PRACH configuration used for legacy UEs will be referred to as the legacy PRACH configuration, and the PRACH configuration used for the new configuration of RedCap UEs will be referred to as the new PRACH configuration. The reasons or motivations for base stations to provide new PRACH configurations to RedCap UEs are as follows.

[0315] Reason 1: The base station can execute different scheduling schemes during the random access procedure depending on the UE type. For example, the base station can repeatedly transmit the PDSCH including RAR and the Message 4PDSCH including message 4 to increase downlink coverage for the RedCap UE. Additionally, the base station can instruct repeated transmission of the Message 3PUSCH including message 3 to increase uplink coverage for the RedCap UE. As mentioned above, in order to schedule the RedCap UE, the base station needs to identify the UE type. This is possible by the RedCap UE transmitting PRACH according to a separate new PRACH configuration.

[0316] Reason 2: Base stations can use different PRACH formats depending on the UE type. For example, a PRACH format with high coverage can be used to increase uplink coverage for RedCap UEs, while normal UEs can use a PRACH format with low coverage. Therefore, a separate new PRACH configuration can be provided to RedCap UEs.

[0317] Reason 3: Typically, the number of RedCap UEs may be greater than the number of normal UEs. Therefore, when normal UEs and RedCap UEs perform random access using the same PRACH configuration, the random access attempts of a small number of normal UEs become difficult due to the large number of random access attempts by RedCap UEs. Therefore, to ensure successful random access for normal UEs, it is necessary to separate the random access processes for RedCap UEs and normal UEs. This is possible by providing a separate new PRACH configuration for RedCap UEs.

[0318] Reason 4: For RedCap UEs, there are applications that periodically transmit data. For example, wireless sensors transmit measurement data at regular intervals. Therefore, the UE is likely to periodically attempt random access. The base station can reduce PRACH overhead through PRACH configurations suitable for the characteristics of RedCap UEs. To this end, a new PRACH configuration can be provided to RedCap UEs.

[0319] The following describes a method for a base station to provide a new PRACH configuration to a RedCap UE.

[0320] Figure 22 A diagram illustrating a PRACH resource configuration according to another embodiment of the present disclosure is shown. Figure 22 (a) is a diagram related to the first method, while Figure 22 (b) is a diagram related to the second method.

[0321] According to the first method, the RedCap UE can receive the new PRACH configuration via the SIB sent from the base station.

[0322] More specifically, the SIB can configure an initial uplink BWP for an uplink cell (NUL or SUL). Here, the initial uplink BWP is the BWP used by the UE during the random access procedure and can also be referred to as the initial uplink BWP. An initial uplink BWP can include existing legacy PRACH configurations and new PRACH configurations. For reference, one or more new PRACH configurations may exist. For convenience, if multiple new PRACH configurations exist, an index can be assigned to distinguish the corresponding new PRACH configuration. For convenience, the index can start from 0.

[0323] According to the second method, the RedCap UE can receive multiple initial uplink BWPs via an SIB transmitted from the base station. Each initial uplink BWP can include a PRACH configuration. More specifically, the SIB can configure existing and new initial uplink BWPs for an uplink cell (NUL or SUL). Each initial uplink BWP can include a PRACH configuration. Specifically, existing initial uplink BWPs can include traditional PRACH configurations, and new initial uplink BWPs can include new PRACH configurations. The UE can select one of the multiple initial uplink BWPs to transmit a PRACH. In this case, the selected initial uplink BWP is the BWP used by the UE during the random access procedure. For reference, one or more new initial uplink BWPs may exist. For convenience, if multiple new initial uplink BWPs exist, an index can be assigned to distinguish the new PRACH configuration of the corresponding new initial uplink BWP. For convenience, the index can start from 0.

[0324] Based on either the first or second method, one or more new PRACH configurations can be provided to the RedCap UE. Here, the RedCap UE can perform random access via one of the multiple new PRACH configurations.

[0325] Assume the base station has provided the UE with a traditional PRACH configuration and a new PRACH configuration. One UE can transmit a preamble according to the traditional PRACH configuration, and the other UE can transmit a preamble according to the new PRACH configuration. The preambles transmitted by the two UEs can differ in at least one aspect—time, frequency, and code—depending on the traditional and new PRACH configurations; therefore, the base station can distinguish between the preambles transmitted by the two UEs. Consequently, the base station needs to send a RAR for random access to each of the two UEs.

[0326] As mentioned above, a UE can determine the RAR it needs to receive by using the index of the preamble or the RA-RNTI corresponding to its own preamble. However, if one UE sends a preamble according to the traditional PRACH configuration and another UE sends a preamble according to the new PRACH configuration, the two UEs cannot determine the RAR to receive in the following situation.

[0327] For example, if the s_id, t_id, and f_id of a preamble selected according to a UE's traditional PRACH configuration are the same as the s_id, t_id, and f_id of a preamble selected according to a UE's new PRACH configuration, then both UEs monitor the PDCCH used for scheduling the RAR based on the same RA-RNTI value. In this case, if the index of the preamble selected by one UE according to the traditional PRACH configuration is the same as the index of the preamble selected by the other UE according to the new PRACH configuration, then both UEs determine that they have the same RAR with the same RAPID. Therefore, both UEs determine the RAR as their own RAR and thus have the same message 3PUSCH scheduling permission and TC-RNTI value.

[0328] In the following text, since problems may occur when the base station provides a new PRACH configuration as described above, a method for resolving this problem is disclosed below.

[0329] According to the first method, the RA-RNTI value can be determined based on which PRACH configuration preamble was sent. If the UE sends a preamble of a traditional PRACH configuration, the UE can determine the RA-RNTI value as follows.

[0330] [Equation 2]

[0331] RA-RNTT=1+s_id+14×t_id+14×80×f_id+14×80×8

[0332] Wherein, s_id is the index of the first OFDM symbol of the PRACH timing (0≤s_id<14), t_id is the index of the first slot of the PRACH timing in the system frame (0≤t_id<80), f_id is the index of the PRACH timing in the frequency domain (0≤f_id<8), and ul_carrier_id is the index of the uplink carrier used for random access preamble transmission (0 for NUL carriers and 1 for SUL carriers).

[0333] The UE can perform a simplified random access procedure based on the new PRACH configuration to reduce latency compared to the traditional PRACH configuration. This procedure is called a 2-step random access procedure. For convenience, the PRACH configuration in the 2-step random access procedure is referred to as 2-step PRACH. The 2-step random access procedure is roughly as follows.

[0334] The UE can send a preamble and data to the base station using PRACH information configured for the two-step random access procedure. The UE can then monitor the PDCCH sent from the base station for a certain period. Here, the UE can monitor the PDCCH scrambled with MsgB-RNTI. The MsgB-RNTI value is determined based on the preamble sent by the UE, and the method for obtaining a specific MsgB-RNTI value will be described later. When a PDCCH scrambled with MsgB-RNTI is received, the UE can receive the PDSCH scheduled by the PDCCH and can send a HARQ-ACK to the base station depending on whether the PDSCH was successfully received.

[0335] The described MsgB-RNTI can be interpreted as the RA-RNTI of the UE performing the 2-step random access procedure. Therefore, if the index of the preamble selected by one UE according to the 2-step PRACH configuration is the same as the index of the preamble selected according to the new PRACH configuration, then the two UEs determine that they have the same RAR with the same RAPID, thus causing the problem that the UE cannot determine the RAR to receive.

[0336] If the UE sends a preamble for the 2-step PRACH configuration, the UE can determine the MsgB-RNTI value as follows.

[0337] [Equation 3]

[0338] MsgB-RNTT=1+s_id+14×t_id+14×80×f_id+14×80×8×ul_carrier_id+14×80×8×2

[0339] Wherein, s_id is the index of the first OFDM symbol of the PRACH timing (0≤s_id<14), t_id is the index of the first slot of the PRACH timing in the system frame (0≤t_id<80), f_id is the index of the PRACH timing in the frequency domain (0≤f_id<8), and ul_carrier_id is the index of the uplink carrier used for random access preamble transmission (0 for NUL carriers and 1 for SUL carriers).

[0340] In one respect, if the UE sends a preamble for a new PRACH configuration, the UE can determine the RA-RNTI value as follows.

[0341] [Equation 4]

[0342] RA-RNTI = X + 1 + s_id + 14 × t_id + 14 × 80 × f_id + 14 × 80 × 8 × (New PRACH Configuration Index)

[0343] Here, the new PRACH configuration index refers to the index assigned to each new PRACH configuration, and can start from 0. X can be determined based on the maximum value that Equation 2, used to obtain RA-RNTI, can have. If s_id = 13, t_id = 79, f_id = 7, and ul_carrier_id = 1 are possible, then X = 17920, which is the maximum value obtainable according to Equation 2.

[0344] The RA-RNTI obtained from this example has the following characteristics.

[0345] If the UE sends a preamble for the traditional PRACH configuration, then according to Equation 2, the value of RA-RNTI is one from 1 to X = 17920. If the UE sends a preamble for the new PRACH configuration, then the value of RA-RNTI is a value greater than or equal to X+1 according to Equation 4. Therefore, a UE that has sent a preamble for the traditional PRACH configuration and a UE that has sent a preamble for the new PRACH configuration can monitor PDCCHs with different RA-RNTI values. Thus, the base station can schedule different RARs for the two UEs by using different RA-RNTIs.

[0346] In another respect, the equation used to obtain RA-RNTI can be expressed as follows.

[0347] [Equation 5]

[0348] RA-RNTI=1+s_id+14×t_id+14×80×f_id+14×80×8×ID

[0349] Here, the content indicated by the ID is as follows.

[0350] -ID=0: Traditional PRACH in NUL carrier

[0351] -ID=1: Traditional PRACH in SUL carrier

[0352] -ID=2: New PRACH with first index

[0353] -ID=3: New PRACH with a second index

[0354] -ID=…

[0355] In this example, when multiple new PRACH configurations are provided, the maximum number of new PRACH configurations is 5. That is, the index of a new PRACH is one of 0, 1, 2, 3, and 4. For reference, the first index is the lowest index, and the second index is the next lowest index. Here, an index can be uniquely assigned to each new PRACH. The index can be configured via a higher-level signal (or RRC signal) used to select each new PRACH, or it can be derived based on the configuration of each new PRACH. The index can be derived based on at least one of the time information and frequency information of the new PRACH configuration.

[0356] On the other hand, if the UE sends a preamble for a new PRACH configuration, the UE can determine the RA-RNTI value as follows.

[0357] [Equation 6]

[0358] RA-RNTI = X + 1 + s_id + 14 × t_id + 14 × 80 × f_id + 14 × 80 × 8 × (New PRACH Configuration Index)

[0359] Here, the new PRACH configuration index refers to the index assigned to each new PRACH configuration, and can start from 0. X can be determined based on the maximum value that Equation 3, used to obtain RA-RNTI, can have. If s_id = 13, t_id = 79, f_id = 7, and ul_carrier_id = 1 are possible, then X = 35840 can be determined according to Equation 3.

[0360] The RA-RNTI obtained from this example has the following characteristics.

[0361] If the UE sends a preamble for a new PRACH configuration, then according to Equation 3, the value of RA-RNTI is one from 1 to X = 35840. If the UE sends a preamble for a new PRACH configuration, then the value of RA-RNTI is a value greater than or equal to X+1 according to Equation 6. Therefore, a UE that has sent a preamble for a traditional PRACH configuration and a UE that has sent a preamble for a new PRACH configuration can monitor PDCCHs with different RA-RNTI values. Therefore, the base station can schedule different RARs for the two UEs by using different RA-RNTIs.

[0362] On the other hand, the equation used to obtain RA-RNTI can be expressed as follows.

[0363] [Equation 7]

[0364] RA-RNTI=1+s_id+14×t_id+14×80×f_id+14×80×8×ID

[0365] Here, the content indicated by the ID is as follows.

[0366] -ID=0: Traditional PRACH in NUL carrier

[0367] -ID=1: Traditional PRACH in SUL carrier

[0368] -ID=2: 2-step PRACH in NUL carrier

[0369] -ID=3: 2-step PRACH in SUL carrier

[0370] -ID=4: New PRACH with first index

[0371] -ID=5: New PRACH with a second index

[0372] In this embodiment, when multiple new PRACH configurations are provided, the maximum number of new PRACH configurations is 2. That is, the index of a new PRACH is one of 0 and 1. For reference, the first index is the lowest index, and the second index is the next lowest index. Here, an index can be uniquely assigned to each new PRACH. The index can be configured via a higher-level signal (or RRC signal) used to select each new PRACH, or it can be derived based on the configuration of each new PRACH. The index can be derived based on at least one of the time information and frequency information of the new PRACH configuration.

[0373] For reference, the RedCap UE can be configured via the SIB to use a method for calculating RA-RNTI. For example, it can be configured via the SIB to use one of Equations 4 or 6 (or 5 or 7). As another example, even without a separate instruction in the SIB, it can be configured to use one of Equations 4 or 6 (or 5 or 7) based on a 2-step RACH configuration. For example, if a 2-step RACH is configured, the RA-RNTI value can be calculated using Equation 6 (or Equation 7); otherwise, it can be calculated using Equation 4 (or Equation 5). Furthermore, the RA-RNTI value is calculated using Equation 6 (or Equation 7) only if a 2-step RACH has been configured and the PRACH resources of the 2-step RACH overlap with the PRACH resources of the RedCap UE; otherwise, it can be calculated using Equation 4 (or Equation 5).

[0374] According to the second method, the search space for monitoring the PDCCH can be determined differently based on which PRACH configuration preamble has been sent. If the UE sends a preamble with a traditional PRACH configuration, the UE can monitor the PDCCH in the first search space based on the RA-RNTI value to receive the RAR. If the UE sends a preamble with a new PRACH configuration, the UE can monitor the PDCCH in the second search space based on the RA-RNTI value to receive the RAR. Here, the RA-RNTI value can be determined based on Equation 1 used to obtain the RA-RNTI. That is, different UEs can all monitor PDCCHs with the same RA-RNTI value, but they can receive the RAR corresponding to the preamble sent by the UE itself by monitoring the PDCCH in different search spaces.

[0375] More specifically, the UE can be notified via signals as follows. The UE can receive a new PRACH configuration for random access and a search space configuration corresponding to the new PRACH configuration via an SIB transmitted from the base station. Here, the UE can identify the following information via the search space configuration.

[0376] - Configure the time slots of the search space based on period and offset information.

[0377] - Configure the number of consecutive time slots in the search space

[0378] - The symbol indicating the start of the search space within a time slot.

[0379] - The PDCCH aggregation level (AL) to be monitored in the search space and the number of PDCCH candidates per AL.

[0380] - DCI format that needs to be monitored in the search space

[0381] The search space corresponding to the new PRACH configuration is associated with CORESET#0. Therefore, the search space corresponding to the preamble of the traditional PRACH configuration and the search space corresponding to the preamble of the new PRACH configuration can be associated with the same CORESET#0, and thus can have the same frequency domain information, CCE to REG mapping, and CORESET duration.

[0382] If no separate search space corresponding to the new PRACH is configured, the UE can monitor the PDCCH in the search space corresponding to the traditional PRACH for RAR reception. In this case, when monitoring the PDCCH, the RA-RNTI value can be based on the equation for obtaining the RA-RNTI proposed in the first method or Equation 1 for obtaining the RA-RNTI.

[0383] According to the third method, the CORESET for monitoring the PDCCH can be determined differently depending on which PRACH configuration preamble the UE has already sent. If the UE sends a preamble with a traditional PRACH configuration, the UE can monitor the PDCCH based on the RA-RNTI value in the search space of the first CORESET to receive the RAR. If the UE sends a preamble with a new PRACH configuration, the UE can monitor the PDCCH based on the RA-RNTI value in the search space of the second CORESET to receive the RAR. Here, the RA-RNTI value can be determined based on Equation 1 used to obtain the RA-RNTI. That is, the UE monitors PDCCHs with the same RA-RNTI value, but can receive the RAR corresponding to the preamble sent by the UE itself by monitoring the PDCCH in the search space of different CORESETs.

[0384] More specifically, the UE can be notified via signals as follows. The UE can receive a new PRACH configuration for random access and a corresponding CORESET configuration via an SIB sent from the base station. Here, via the CORESET configuration, the UE can recognize the following information.

[0385] - The frequency information of the CORESET. This can be identified in units of 6 consecutive PRB sets.

[0386] - The mapping between REG and CCE included in CORESET. This can be a localized mapping or a distributed mapping.

[0387] - The number of symbols included in CORESET. This can be one symbol, or two or three consecutive symbols.

[0388] According to the fourth method, the initial downlink (DL) BWP for random access can be determined differently based on which PRACH configuration preamble the UE has sent. If the UE sends a preamble with a traditional PRACH configuration, the UE can monitor the PDCCH based on the RA-RNTI value in the first DL initial BWP to receive the RAR. If the UE sends a preamble with a new PRACH configuration, the UE can monitor the PDCCH based on the RA-RNTI value in the second DL initial BWP to receive the RAR. Here, the RA-RNTI value can be determined based on Equation 1 used to obtain the RA-RNTI. In each DL initial BWP, the CORESET and search space for monitoring the PDCCH can be configured. That is, the UE monitors PDCCHs with the same RA-RNTI value, but can receive the RAR corresponding to the preamble sent by the UE itself by monitoring the PDCCH in different DL initial BWPs.

[0389] III. Frequency Hopping Method for RedCap UEs

[0390] Figure 23 A diagram illustrating the scheduling of the physical uplink shared channel in the time domain is shown. Figure 24 A diagram illustrating the scheduling of the physical uplink shared channel in the frequency domain is shown.

[0391] based on Figure 23 and Figure 24 This section describes the method by which the UE transmits the Physical Uplink Shared Channel (PUSCH).

[0392] The UE can transmit uplink data via the Physical Uplink Shared Channel. The UE can transmit uplink data using either a method of scheduling the transmission of the Physical Uplink Shared Channel in the Downlink Control Information (DCI) delivered via the Physical Downlink Control Channel (PDCCH) (Dynamic Grant (DG)) or a method of transmitting the Physical Uplink Shared Channel according to resources and transmission methods pre-configured from the base station (Configuration Grant (CG)).

[0393] Downlink control information (DCI) received via the UE's PDCCH may include PUSCH scheduling information. This scheduling information may include time-domain information (hereinafter, Time Domain Resource Assignment (TDRA)) and frequency-domain information (Frequency Domain Resource Assignment (FDRA)). The UE can interpret the DCI received via the PDCCH based on the control resource set and search space information, and can perform operations indicated by the DCI. The DCI may include one of the DCI formats 0_0, 0_1, or 0_2 for scheduling the Physical Uplink Shared Channel (PUSCH).

[0394] The time-domain information of the PUSCH indicated by the TDRA field in DCI format 0_0, 0_1, or 0_2 includes the following: K2 is the offset between the time slot from which the base station receives the PDCCH and the time slot from which the UE transmits the PUSCH. The Start and Length Indication Value (SLIV) is a value obtained in the time slot indicated by K2 by jointly encoding the start symbol index (S) and symbol length (L) of the PUSCH.

[0395] When the UE receives DCI format 0_0, 0_1, or 0_2 for scheduling PUSCH in time slot n, it determines that the time slot is floor(n*2). μPUSCH / n*2 μPDCCH )+K2. Wherein, μPUSCH and μPDCCH are the subcarrier spacing (SCS) of the cell that schedules PUSCH and the cell that receives PDCCH, respectively.

[0396] For example, refer to Figure 23(a) The subcarrier spacing of the cell receiving PDCCH is the same as that of the cell scheduling PUSCH. Therefore, when the UE receives PDCCH in slot n, for example, when the UE receives an indication that k2 is 4, the UE determines that the slot for scheduling PUSCH is slot n+K2=n+4.

[0397] Both mapping types A and B can be applied to the physical uplink shared channel transmitted by the UE. The SLIV obtained by joint encoding of the start symbol index and symbol length of the PUSCH has different value ranges depending on the PUSCH mapping type. In PUSCH mapping type A, resource allocation including only DMRS symbols is possible, and the DMRS symbols are located in the third or fourth OFDM symbols of the time slot, depending on the value indicated by the higher layer. That is, in the case of PUSCH mapping type A, the start symbol index (S) of the PUSCH is 0, and the length (L) of the PUSCH can have one of the values ​​from 4 to 14 (12 for extended CP) depending on the position of the DMRS symbols. In the case of PUSCH mapping type B, the DMRS symbols are always the first symbols of the PUSCH, and therefore S can have a value from 0 to 13 (11 for extended CP), and L can have one of the values ​​from 1 to 14 (12 for extended CP). Furthermore, a PUSCH cannot cross a time slot boundary, so the values ​​of S and L need to satisfy S + L = 14 (12 for extended CP).

[0398] Figure 23 (b) An example of a PUSCH based on the PUSCH mapping type is illustrated. Starting from the top, the UE sequentially determines that the PUSCH of mapping type A is a DMRS symbol with a start symbol index (S) of 0 and a length (L) of 7; the PUSCH of mapping type A is a DMRS symbol with a start symbol index (S) of 0 and a length (L) of 7; and the PUSCH of mapping type B is a DMRS symbol with a start symbol index (S) of 5 and a length (L) of 5. The frequency domain information of the PUSCH indicated by the FDRA field in DCI format 0_0, 0_1, or 0_2 can be divided into two types based on the frequency resource allocation type.

[0399] The first type is frequency resource allocation type 0, where a fixed number of resource block groups (RBGs) are generated by combining them according to the number of RBs included in the BWP configured for the UE, and the UE is indicated with a bitmap in units of RBGs to determine whether to use an RBG. The number of PRBs included in an RBG is configured from higher layers, and more PRBs are configured as the number of RBs included in the BWP configured for the UE increases. For example, refer to... Figure 24(a) When the BWP size configured for the UE is 72 PRBs and one RBG comprises 4 PRBs, the UE determines four PRBs into one RBG in ascending order from PRB 0. That is, if mapping is performed up to RBG 17 according to the order that RBG 0 includes PRBs 0 to 3 and RBG 1 includes PRBs 4 to 7, the UE receives 1 bit (0 or 1) per RBG, for a total of 18 bits, to determine whether to use a PRB in the corresponding RBG. In this case, if the bit value is 0, the UE determines not to schedule a PUSCH in any PRB of the RBG, and if the bit value is 1, the UE determines to schedule a PUSCH in all PRBs of the RBG. Alternatively, the bit values ​​can be applied in reverse order.

[0400] The second type is Frequency Resource Allocation Type 1, which can indicate information about consecutive PRBs allocated based on the size of the UE's active BWP or initial BWP. This information is obtained by jointly encoding the start index (S) and length (L) of the consecutive PRBs. For example, refer to... Figure 24 (b) If the UE's BWP size is 50 PRBs and PUSCH is scheduled from PRB 2 to PRB 11, then the starting index of consecutive PRBs is 2 and their length is 10. This is achieved by receiving RIV=N. size BWP *(L-1)+S=50*(10-1)+2=452, the UE can determine the starting index and length of the consecutive PRBs for scheduling its PUSCH as 2 and 10 respectively.

[0401] For DCI formats 0_1 or 0_2 used for scheduling PUSCH only, the UE can be configured from a higher layer to use only one of the two frequency resource allocation types for PUSCH or to use both types dynamically. If configured to use both types dynamically, the UE can determine one of the types to schedule PUSCH via 1 bit of the most significant bit (MSB) of the FDRA field in DCI format 0_1 ​​or 0_2.

[0402] Support is provided for licensed (configured license) uplink shared channel transmission schemes configured to support uplink URLLC transmissions, etc., and this scheme is also known as unlicensed transmission. The configured licensed uplink transmission scheme is one in which the UE transmits uplink shared channels through the corresponding resources when the base station configures resources available for uplink transmission for the UE via a higher layer (i.e., RRC signaling). This scheme can be divided into two types based on the availability of activation or release via DCI.

[0403] Type 1 - Configuration-based license-based transport schemes are schemes used to configure resources and transport schemes for pre-configured license-based transport at a higher layer.

[0404] Type 2 - The configuration-based licensed transport scheme is a scheme in which the configured licensed transport is configured at a higher layer, wherein the DCI delivered through the physical downlink control channel indicates the resources and schemes used for transport.

[0405] The configured licensed uplink transmission scheme supports URLLC transmission and therefore supports repeated transmissions in multiple time slots to ensure high reliability. In this case, the redundancy version (RV) sequence is configured with one of {0,0,0,0}, {0,2,3,1}, and {0,3,0,3}, and in the nth repeated transmission, the RV corresponding to the (mod(n-1,4)+1)th value is used. A UE configured with repeated transmissions can start repeated transmissions only in time slots where the RV value is 0. However, if the RV sequence is {0,0,0,0} and repeated transmissions are performed in 8 time slots, repeated transmissions cannot start in the 8th time slot. The UE terminates repeated transmissions when the number of repeated transmissions configured in a higher layer is reached, when the time slot ends, or when a UL license with the same HARQ procedure ID is received. Here, the UL license refers to the DCI used to schedule PUSCH.

[0406] To improve the reliability of reception and transmission of the physical uplink shared channel between the base station and the UE in a wireless communication system, the UE can be configured to repeatedly transmit the uplink shared channel from the base station. This is achieved by referring to... Figure 25 Describe it.

[0407] Figure 25 A diagram illustrating repeated transmissions of a physical uplink shared channel according to an example is shown.

[0408] refer to Figure 25 The PUSCH retransmissions that a UE can perform can be divided into two types.

[0409] First, the transmission process for PUSCH retransmission type A of the UE is as follows. When the UE receives DCI format 0_1 ​​or 0_2 from the base station via the PDCCH used for scheduling PUSCH, PUSCH retransmission in K consecutive time slots is possible. Here, the UE can be configured with a K value from a higher layer, or the K value can be added to the TDRA field of the DCI for reception. For example, refer to... Figure 25(a) If it is assumed that the UE receives the PDCCH for scheduling PUSCH in time slot n, and receives 2 as the K2 value and 4 as the K value from the DCI format received via the PDCCH, then the UE starts transmitting PUSCH in time slot n+K2 (i.e., n+2), and the UE repeatedly transmits PUSCH from time slot n+2 to time slot n+2+K-1 (i.e., n+5). In this case, the time and frequency resources for transmitting PUSCH in each time slot are the same as the time and frequency resources indicated by the DCI. That is, PUSCH can be transmitted in the same symbols and PRBs within the time slot.

[0410] Subsequently, the UE transmission process for PUSCH repetition type B, used to support low-latency PUSCH repetition to meet URLLC requirements, is as follows. The start symbol (S) and length (L) of the PUSCH can be indicated from the base station to the UE via the TDRA field. Here, the PUSCH obtained using the indicated start symbol and length is not the actual PUSCH, but a temporarily obtained PUSCH, and is referred to as the nominal PUSCH. Additionally, the nominal repetition count (N) of the indicated nominal PUSCH can be indicated to the UE via the TDRA field. The UE can determine the same number of nominal repetitions (N) as the nominal PUSCH indicated via the TDRA field. Here, the same number of nominal repetitions (N) as the nominal PUSCH has the same length, i.e., L, and the nominal PUSCH is continuous on the time axis without individual symbols.

[0411] The UE can determine the actually transmitted (actual) PUSCH from the nominal PUSCH. A nominal PUSCH can be determined based on one or more actually transmitted (actual) PUSCHs. The base station can indicate or configure symbols that are not available in PUSCH retransmission type B for the UE. This is called an invalid symbol. The UE can exclude invalid symbols from the nominal PUSCH. As mentioned above, the nominal PUSCH is determined consecutively in symbols, but it can be determined discontinuously when excluding invalid symbols. The actually transmitted (actual) PUSCH can be determined based on consecutive symbols in a nominal PUSCH other than invalid symbols. Here, if consecutive symbols cross time slot boundaries, the actually transmitted (actual) PUSCH can be determined based on boundary division.

[0412] For reference, invalid symbols may include at least the DL symbols configured by the base station for the UE.

[0413] For example, refer to Figure 25(b) Assume the UE is scheduled for a PUSCH transmission with a length of 5 symbols, starting from the 12th OFDM symbol in the first time slot (time slot n), and is indicated to have four Type B repetitions. The nominal PUSCHs are as follows: The first nominal PUSCH (nominal #1) includes symbols (n,11), (n,12), (n,13), (n+1,0), and (n+1,1). The second nominal PUSCH (nominal #2) includes symbols (n+1,2), (n+1,3), (n+1,4), (n+1,5), and (n+1,6). The third nominal PUSCH (nominal #3) includes symbols (n+1,7), (n+1,8), (n+1,9), (n+1,10), and (n+1,11). The fourth nominal PUSCH (nominal #4) includes symbols (n+1,12), (n+1,13), (n+2,0), (n+2,1), and (n+2,2). Here, symbol (n,K) represents symbol k of slot n. For normal CP, symbol k indices range from 0 to 13, and for extended CP, symbol k indices range from 0 to 11.

[0414] Assume that invalid symbols are configured or indicated in symbols 6 and 7 of time slot n+1. Based on the invalid symbols configured or indicated by the base station, the last symbol of the second nominal PUSCH (nominal #2) is excluded, and the first symbol of the third nominal PUSCH (nominal #3) is excluded.

[0415] The first nominal PUSCH (nominal #1) is divided into two actual PUSCHs (actual #1 and actual #2) by the time slot boundary. The second nominal PUSCH (nominal #2) and the third nominal PUSCH (nominal #3) are then divided into corresponding actual PUSCHs (actual #3 and actual #4) by combining consecutive symbols excluding invalid symbols. Finally, the fourth nominal PUSCH (nominal #4) is divided into two actual PUSCHs (actual #5 and actual #6) by the time slot boundary. The UE then transmits the actual PUSCHs.

[0416] An actual transmitted (actual) PUSCH must include at least one DMRS symbol, and when configuring PUSCH retransmission type B, a full-length actual transmitted (actual) PUSCH with one symbol can be omitted. This is because in the case of an actual transmitted (actual) PUSCH with one symbol, information other than DMRS cannot be transmitted.

[0417] To obtain diversity gain in the frequency domain, frequency hopping can be configured for the UE.

[0418] For PUSCH repetitive transmission type A, the UE can be configured with either intra-slot frequency hopping (performing frequency hopping within a time slot) or inter-slot frequency hopping (performing frequency hopping for each time slot). If intra-slot frequency hopping is configured for the UE, the UE splits the PUSCH in the time domain within the time slot used for PUSCH transmission, so that one half of the PUSCH is transmitted in the scheduled PRB, and the other half is transmitted in the PRB obtained by adding an offset value to the scheduled PRB. In this case, two or four offset values ​​are configured via a higher layer based on the active BWP size, and one of these values ​​can be indicated to the UE via the DCI. If inter-slot frequency hopping is configured for the UE, the UE transmits the PUSCH in the scheduled PRB in time slots with even-numbered time slot indices, and transmits the PUSCH in the PRB obtained by adding an offset value to the scheduled PRB in odd-numbered time slots.

[0419] For PUSCH repetition transmission type B, one of two configurations can be set: inter-repetition frequency hopping, which performs frequency hopping at the nominal PUSCH boundary, and inter-slot frequency hopping, which performs frequency hopping within each slot. If inter-repetition frequency hopping is configured for the UE, the UE transmits the actual transmitted (actual) PUSCH corresponding to the odd-numbered nominal PUSCH in the scheduled PRB, and transmits the actual transmitted (actual) PUSCH corresponding to the even-numbered nominal PUSCH in the PRB obtained by adding offset values ​​to the scheduled PRB. In this case, two or four offset values ​​are configured via a higher layer based on the active BWP size, and one of these values ​​can be indicated to the UE via the DCI. If inter-slot frequency hopping is configured for the UE, the UE transmits the actual transmitted (actual) PUSCH for slots with even-numbered slot indices in the scheduled PRB, and transmits the actual transmitted (actual) PUSCH for odd-numbered slots in the PRB obtained by adding offset values ​​to the scheduled PRB.

[0420] When performing repeated PUSCH transmissions, if a symbol scheduled for PUSCH transmission overlaps with a semi-statically configured DL symbol or a symbol configured for SS / PBCH block reception in a specific time slot, the UE will not perform the overlapping PUSCH transmission in the corresponding time slot and will not delay the transmission to a subsequent time slot.

[0421] based on Figure 26 This section describes the method by which the UE transmits the Physical Uplink Control Channel (PUCCH).

[0422] Figure 26 This is a diagram illustrating the scheduling of the physical uplink control channel.

[0423] refer to Figure 26When a UE receives a DCI format 1_0, 1_1, or 1_2 for scheduling a Physical Uplink Control Channel, the UE needs to send the scheduled uplink control channel. The Physical Uplink Control Channel may include Uplink Control Information (UCI), and the UCI may include HARQ-ACK, SR, and CSI information. The HARQ-ACK information can be of two types regarding whether the channel has been successfully received. When scheduling a Physical Downlink Shared Channel (PDSCH) via DCI format 1_0, 1_1, or 1_2, the first type can indicate whether the reception of the PDSCH was successful. When DCI format 1_0, 1_1, or 1_2 is a DCI indicating the release of a Semi-Static Physical Downlink Shared Channel (SPS PDSCH), the second type can indicate whether the reception of DCI format 1_0, 1_1, or 1_2 was successful.

[0424] To send the PUCCH used for delivering HARQ-ACK, the PDSCH-to-HARQ_feedback timing indicator field included in DCI format 1_0, 1_1, or 1_2 can indicate a K1 value, which is a value about the time slot of the uplink control channel that needs to be sent. Here, the K1 value can be a non-negative integer value. The K1 value in DCI format 1_0 can indicate one of {0, 1, 2, 3, 4, 5, 6, 7}. The K1 value that can be indicated by DCI format 1_1 or 1_2 can be configured or set from a higher layer.

[0425] The UE can determine the time slot for transmitting the uplink control channel, which includes HARQ-ACK information of the first type, as follows: The UE can determine the uplink time slot that overlaps with the last symbol of the physical downlink shared channel (PDSCH) corresponding to the HARQ-ACK information. When the index of this uplink time slot is m, the uplink time slot in which the UE transmits the physical uplink control channel, which includes HARQ-ACK information, can be m+K1. Here, the index of the uplink time slot is based on the subcarrier spacing value of the uplink BWP for transmitting the uplink control channel.

[0426] For reference, if the UE is configured with downlink slot aggregation, the end symbol indicates the last symbol of the PDSCH scheduled in the last slot among the slots in which the Physical Downlink Shared Channel (PDSCH) is received.

[0427] refer to Figure 26Assume the subcarrier spacing of the DL BWP for receiving PDCCH, the subcarrier spacing of the DL BWP for scheduling PDSCH, and the subcarrier spacing of the UL BWP for transmitting PUCCH are the same. Assume the UE receives the PDCCH for scheduling PDSCH and PUCCH from the base station in time slot n, where the DCI indications delivered by the PDCCH are K0=2 and K1=3. If the last symbol of the PDSCH has been received in time slot n+K0 (i.e., n+2), the UE needs to transmit the HARQ-ACK of the PDSCH via PUCCH in time slot n+2+K1 (i.e., n+5).

[0428] To ensure wide coverage in the NR system, the UE can be configured to repeatedly transmit long PUCCHs (PUCCH formats 1, 3, and 4) in 2, 4, or 8 time slots. If the UE is configured to repeatedly transmit PUCCHs, the same UCI is repeatedly transmitted in each time slot. This will refer to... Figure 27 Describe it.

[0429] Figure 27 This is a diagram illustrating the repeated transmission of the physical uplink control channel.

[0430] refer to Figure 27 When the PDSCH reception ends in time slot n and K1 = 2, the UE transmits PUCCH in time slot n + K1 (i.e., n + 2). In this case, if the number of PUCCH retransmissions is configured for the UE and set to N... repeat PUCCH If the value is 4, then the PUCCH will be repeatedly transmitted from time slot n+2 to time slot n+5. The symbol configuration of the repeatedly transmitted PUCCH is the same. That is, the repeatedly transmitted PUCCH starts with the same symbol in each time slot and includes the same number of symbols.

[0431] To obtain diversity gain in the frequency domain, frequency hopping can be configured for the UE. Intra-slot frequency hopping (performing frequency hopping within a time slot) and inter-slot frequency hopping (performing frequency hopping for each time slot) can be configured. If intra-slot frequency hopping is configured for the UE, the UE splits the PUCCH in half in the time domain within the time slot used for PUCCH transmission, transmitting one half in the first PRB and the other half in the second PRB. In this case, the first and second PRBs can be configured for the UE via a higher layer used for configuring PUCCH resources. When inter-slot frequency hopping is configured for the UE, the UE transmits the PUCCH in the first PRB in time slots with even-numbered time slot indices and in the second PRB in time slots with odd-numbered time slot indices.

[0432] When performing a PUCCH retransmission, if the symbol required for PUCCH transmission overlaps with the position of a semi-statically configured DL symbol or a symbol configured to receive SS / PBCH blocks in a specific time slot, the UE will not transmit PUCCH in the corresponding time slot and will delay the transmission to a subsequent time slot, such that if the PUCCH symbol does not overlap with the position of a semi-statically configured DL symbol or a symbol configured to receive SS / PBCH blocks in the corresponding time slot, the UE will transmit PUCCH.

[0433] When transmitting PUSCH or PUCCH, the UE can use a frequency hopping scheme to perform the transmission in order to obtain frequency diversity gain. Here, a frequency hopping scheme refers to transmitting PUSCH or PUCCH in the zeroth PRB set and in the first PRB set. For reference, in the description of this disclosure, PUSCH or PUCCH transmitted in the zeroth PRB set is referred to as hop 0, and PUSCH or PUCCH transmitted in the first PRB set is referred to as hop 1. This disclosure only describes up to two hops (hop 0 and hop 1), but the number of hops can be further increased.

[0434] When the UE sends PUSCH or PUCCH, the method for determining the zeroth PRB set for hop 0 and the first PRB set for hop 1 is as follows.

[0435] The PUCCH preceding the RRC connection can be determined as follows. For reference, the PUCCH preceding the RRC connection is the PUCCH used for HARQ-ACK transmission, and HARQ-ACK is a PDSCH reception success response including Msg4.

[0436] The UE selects one PUCCH resource from 16 PUCCH resources. In this case, the selection is determined based on the PUCCH resource indicator included in the DCI format used for PUCCH scheduling or the index of the control channel element (CCE) that has been received in the DCI format. If the index of the selected PUCCH resource is r... PUCCH Then the index can have values ​​0, 1, ..., 15.

[0437] If r PUCCH If the value is one of 0, 1, ..., 7, then the index of the zeroth PRB set of the selected PUCCH resource is... And the index of the first PRB set in jump 1 is If r PUCCH If the value is one of 8, 9, ..., 15, then the index of the zeroth PRB set of the selected PUCCH resource is... And the index of the first PRB set in jump 1 is

[0438] Here, N size BWP This refers to the number of PRBs included in the active BWP used for PUCCH transmission. Here, if the PUCCH sends a HARQ-ACK for Msg4 PDSCH, the active BWP is the initial UL BWP. This initial UL BWP is the UL BWP used for UE cell access and is configured in the System Information Block (SIB1). CS It is the number of the initial circular shift index, and RB BWP offset The initial cyclic shift index is shown in Table 4.

[0439] [Table 4]

[0440]

[0441] Here, if the index of the RB starting at the zeroth PRB set of hop 0 is 0, this indicates the lowest PRB of the UE's active BWP. For reference, if the PUCCH sends a HARQ-ACK for Msg4PDSCH, the active BWP is the initial UL BWP. That is, the index of the RB starting at the zeroth PRB set of hop 0 is interpreted as the index of the initial UL BWP.

[0442] The PUCCH following the RRC connection can be determined as follows.

[0443] The indices of the lowest PRB in the zeroth PRB set of hop 0 and the lowest PRB in the first PRB set of hop 1 in the PUCCH can be configured for the UE's PUCCH resources via RRC signals. That is, if a PUCCH resource is used, the UE can transmit hop 0 and hop 1 by using the indices of the lowest PRB in the zeroth PRB set of hop 0 and the lowest PRB in the first PRB set of hop 1 configured in the PUCCH resource. Here, if the PRB index is 0, this indicates the lowest PRB of the UE's active BWP. In other words, the PRB index is interpreted as the index of the UE's active BWP.

[0444] For PUSCH, it can be determined as follows.

[0445] The UE can determine the zeroth PRB set for hop 0 via the DCI used for scheduling PUSCH or the DCI / RRC signal used for activating PUSCH. Here, the DCI used for scheduling PUSCH or the DCI / RRC signal used for activating PUSCH may include a Frequency Domain Resource Assignment (FDRA) field. The FDRA field may include the index of the RB starting at the zeroth PRB set for hop 0 and the number of consecutive RBs. Here, if the index of the RB starting at the zeroth PRB set for hop 0 is 0, this indicates the lowest PRB of the UE's active BWP. That is, the index of the RB starting at the zeroth PRB set for hop 0 is interpreted as the index of the UE's active BWP. The UE needs to determine the index of the RB starting at the first PRB set for hop 1. This can be determined via the following equation.

[0446]

[0447] Here, RB start (0) represents the index of the RB starting from the zeroth PRB set (jump 0), where RB... start (1) Indicates the index of the RB that begins in the first PRB set of jump 1. RB offset This represents the PRB gap between the zeroth PRB set of hop 0 and the first PRB set of hop 1. The base station can configure and indicate the RB for the UE. offset , and RB offset The value can be 0, 1, ..., N BWP size One of -1. N BWP size This indicates the number of PRBs included in the UE's active BWP. If the index of the RB starting at the beginning of the first PRB set in hop 1 is 0, where this index is obtained using the equation, then this indicates the lowest PRB in the UE's active BWP. That is, the index of the RB starting at the beginning of the first PRB set in hop 1 (RB... start (1) is interpreted as the index of the UE’s active BWP.

[0448] When PUSCH sends Msg3, RB offset It can have one of the following values. If the initial UL BWP size is less than 50 RBs, then RB offset It can be and One of the values, and if the initial UL BWP size is greater than 50 RBs, then RB offset It can be and One of the values. Here, for Msg3 PUSCH, since the initial UL BWP is the active BWP, N BWP sizeIt is the number of RBs included in the initial UL BWP.

[0449] In the frequency hopping scheme described above, the zeroth PRB set for hop 0 and the first PRB set for hop 1 are located within the active BWP. For reference, in the case of the PUSCH (i.e., Msg3PUSCH) and PUCCH (i.e., the PUCCH that sends HARQ-ACK for Msg4 PDSCH) prior to the RRC connection, the active BWP is the initial UL BWP. However, in the following situations, the UE may need to hop frequencies in a band other than the active BWP.

[0450] The first example is a case where the RF bandwidth supported by the UE is significantly less than the bandwidth supported by the cell. For example, refer to... Figure 28 .

[0451] Figure 28 This is a diagram illustrating frequency hopping.

[0452] refer to Figure 28 Assume the UE's RF bandwidth supports up to 20MHz, and the cell supports a bandwidth of 100MHz. Since the UE's RF bandwidth supports up to 20MHz, the UE's active BWP can only support up to 20MHz. Therefore, if a frequency hopping scheme is used according to the above approach, the achievable frequency diversity gain may be very small.

[0453] - In the second example, even if the UE supports a significant RF bandwidth, the UE still needs to maintain a small active BWP bandwidth to reduce power consumption. In this case, as in the first example, if a frequency hopping scheme is used according to the above approach, the achievable frequency diversity gain may be very small.

[0454] In order to improve transmission based on frequency hopping within the active BWP as described above, the following frequency hopping can be considered.

[0455] Figure 29 This is a diagram illustrating broadband frequency hopping.

[0456] refer to Figure 29 (a) The first PRB set of hop 0 and the second PRB set of hop 1 of the UE can be far from a specific frequency. In this case, a hop can be located within the active BWP. More specifically, the zeroth PRB set of hop 0 is located within the UE's active BWP, but the first PRB set of hop 1 can be located in a frequency band outside the UE's active BWP. Conversely, the first PRB set of hop 1 is located within the UE's active BWP, but the zeroth PRB set of hop 0 can be located in a frequency band outside the UE's active BWP. As another example, refer to... Figure 18(b) The first PRB set of hop 0 and the second PRB set of hop 1 of the UE can be located away from a specific frequency. In this case, the two hops can be located in a frequency band outside the active BWP. More specifically, the zeroth PRB set of hop 0 and the first PRB set of hop 1 can be located in a frequency band outside the active BWP of the UE.

[0457] like Figure 29 The example illustrates a signaling scheme by which a UE transmits one or two hops in a frequency band outside of the active BWP.

[0458] For the PUCCH preceding the RRC connection, it can be determined as follows.

[0459] If r PUCCH If the value is one of 0, 1, ..., 7, then the index of the zeroth PRB set of the selected PUCCH resource is... The index of the first PRB set in jump 1 is If r PUCCH If the value is one of 8, 9, ..., 15, then the index of the zeroth PRB set of the selected PUCCH resource is... The index of the first PRB set in jump 1 is Here, N BWP size This refers to the number of PRBs included in a specific BWP used for PUCCH transmission. Here, if the PUCCH sends a HARQ-ACK for Msg4 PDSCH, the specific BWP is the initial UL BWP of the normal UE. The initial UL BWP of the normal UE is the UL BWP used for cell access of the normal UE and is configured in the System Information Block (SIB1). For reference, the UE in the first or second example above has an active BWP with a bandwidth less than the bandwidth of the initial UL BWP of the normal UE. That is, the UE can determine the zeroth PRB set for hop 0 and the first PRB set for hop 1 based on a bandwidth greater than the bandwidth of the active BWPs that the UE can have. Here, if the index of the RB starting at the zeroth PRB set for hop 0 is 0, this indicates the lowest PRB of the specific BWP. That is, if the index of the RB starting at the zeroth PRB set for hop 0 is 0, this indicates the lowest PRB of the initial UL BWP of the normal UE.

[0460] The PUCCH following the RRC connection can be determined as follows.

[0461] The indexes of the lowest PRB in the zeroth PRB set of hop 0 and the lowest PRB in the first PRB set of hop 1 of the PUCCH can be configured for the UE's PUCCH resources via RRC signals. That is, if a PUCCH resource is used, the UE can transmit hop 0 and hop 1 by using the indexes of the lowest PRB in the zeroth PRB set of hop 0 and the lowest PRB in the first PRB set of hop 1 configured in the PUCCH resource. Here, if the PRB index is 0, this indicates the lowest PRB of the UE's specific BWP. In other words, the PRB index is interpreted as the index of the UE's specific BWP. Here, the specific BWP can be one of the following.

[0462] As an example of a specific BWP, the UE can be configured with a specific BWP from the base station. The UE can be configured with the index of the RB that starts the specific BWP from the base station or the number of PRBs included in the BWP. In this case, the starting RB index of the specific BWP can be configured based on the starting RB index of the UE's active BWP. That is, the difference between the starting RB index of the specific BWP and the starting RB index of the UE's active BWP can be configured.

[0463] As an example of a specific BWP, the UE can assume the maximum BWP of the cell. The maximum BWP of the cell can be determined as follows. Upon initial access to the cell, the UE configures the frequency position of the PRB corresponding to cell common PRB index 0. 275 consecutive PRBs starting from cell common PRB index 0 can be grouped together to be determined as the maximum BWP of the cell. That is, any BWP is included in the maximum BWP of the cell. By using the maximum BWP of the cell in this way, the base station can perform frequency hopping and send PUCCH to the UE at any frequency of the cell.

[0464] As an example of a specific BWP, the UE can use the initial UL BWP of a normal UE. The initial UL BWP of a normal UE is the UL BWP used for cell access of the normal UE and is configured in the System Information Block (SIB1). For reference, the UE in the first or second example above has an active BWP with a bandwidth less than that of the initial UL BWP of a normal UE.

[0465] For PUSCH, it can be determined as follows.

[0466] (1) First embodiment

[0467] Figure 30 This is a diagram illustrating broadband frequency hopping according to an embodiment of the present disclosure.

[0468] refer to Figure 30The UE can determine the zeroth PRB set for hop 0 via the DCI used for scheduling PUSCH or the DCI / RRC signal used for activating PUSCH. Here, the DCI used for scheduling PUSCH or the DCI / RRC signal used for activating PUSCH may include a Frequency Domain Resource Assignment (FDRA) field. The FDRA field may include the index of the RB starting at the zeroth PRB set for hop 0 and the number of consecutive RBs. Here, if the index of the RB starting at the zeroth PRB set for hop 0 is 0, this indicates the lowest PRB of the UE's active BWP. That is, the index of the RB starting at the zeroth PRB set for hop 0 is interpreted as the index of the UE's active BWP. The UE needs to determine the index of the RB starting at the first PRB set for hop 1. This can be determined via the following equation.

[0469] RB start (1)=(RB start (0)+RB offset )

[0470] Here, RB start (0) represents the index of the RB starting from the zeroth PRB set (jump 0), where RB... start (1) Indicates the index of the RB that begins the first PRB set of jump 1. offset This represents the PRB gap between the zeroth PRB set of hop 0 and the first PRB set of hop 1. The base station can configure and indicate the RB for the UE. offset , and RB offset The value can be one of a positive number, 0, or a negative number. More specifically, RB offset The value can be one of -274, -273, ..., 0, ..., 273 and 274. If the index of the RB starting at the beginning of the first PRB set of hop 1 is 0, where the index is obtained using the equation, this indicates the lowest PRB of the UE's active BWP. That is, the index of the RB starting at the beginning of the first PRB set of hop 1 (RB start (1) is interpreted as the index of the UE's active BWP. If the index of the RB starting at the first PRB set of hop 1 is negative, this indicates a PRB in a frequency band lower than the frequency band of the UE's active BWP. For example, if the index of the RB starting at the first PRB set of hop 1 is -A, this indicates a PRB that is A PRBs lower than the lowest PRB of the UE's active BWP.

[0471] (2) Second embodiment

[0472] Figure 31 This is a diagram illustrating broadband frequency hopping according to another embodiment of the present disclosure.

[0473] refer to Figure 31The UE can determine the zeroth PRB set for hop 0 via the DCI used for scheduling PUSCH or the DCI / RRC signal used for activating PUSCH. Here, the DCI used for scheduling PUSCH or the DCI / RRC signal used for activating PUSCH may include a Frequency Domain Resource Assignment (FDRA) field. The FDRA field may include the index of the RB starting at the zeroth PRB set for hop 0 and the number of consecutive RBs. Here, if the index of the RB starting at the zeroth PRB set for hop 0 is 0, this indicates the lowest PRB of the UE's active BWP. That is, the index of the RB starting at the zeroth PRB set for hop 0 is interpreted as the index of the UE's active BWP. The UE needs to determine the index of the RB starting at the first PRB set for hop 1.

[0474] This can be determined by the following equation.

[0475]

[0476] Here, RB start (0) represents the index of the RB starting from the zeroth PRB set (jump 0), where RB... start (1) Indicates the index of the RB that begins the first PRB set of jump 1. offset This represents the PRB gap between the zeroth PRB set of hop 0 and the first PRB set of hop 1. The base station can configure and indicate the RB for the UE. offset The UE can be configured with a specific BWP from the base station, wherein the first PRB set of hop 1 can be located in that specific BWP. This specific BWP can include N VBWP size Each PRB. This specific BWP may include the UE's active BWP. offset VBWP This represents the difference between the index of the lowest PRB of the UE's active BWP and the lowest index of a specific BWP.

[0477] If the index of the RB starting at the first PRB set of hop 1 is 0, where the index is obtained using the equation, this indicates the lowest PRB of the UE's active BWP. That is, the index of the RB starting at the first PRB set of hop 1 (RB... start (1) is interpreted as the index of the UE's active BWP. If the index of the RB starting at the first PRB set of hop 1 is negative, this indicates a PRB in a frequency band lower than the frequency band of the UE's active BWP. For example, if the index of the RB starting at the first PRB set of hop 1 is -A, this indicates a PRB that is A PRBs lower than the lowest PRB of the UE's active BWP.

[0478] (3) Third embodiment

[0479] Figure 32 This is a diagram illustrating broadband frequency hopping according to another embodiment of the present disclosure.

[0480] refer to Figure 32 In the first or second embodiment described above, the UE determines the frequency positions of the zeroth PRB set for hop 0 and the first PRB set for hop 1. In this case, the UE's active BWP is fixed. A third embodiment of this disclosure proposes a method for the UE to move its active BWP within a frequency band. The UE can determine the zeroth PRB set for hop 0 via a DCI signal for scheduling PUSCH or a DCI / RRC signal for activating PUSCH. Here, the DCI signal for scheduling PUSCH or the DCI / RRC signal for activating PUSCH may include a Frequency Domain Resource Assignment (FDRA) field. The FDRA field may include the index of the RB starting from the zeroth PRB set for hop 0 and the number of consecutive RBs. Here, if the index of the RB starting from the zeroth PRB set for hop 0 is 0, this indicates the lowest PRB of the UE's active BWP. That is, the index of the RB starting from the zeroth PRB set for hop 0 is interpreted as the index of the UE's active BWP. The UE needs to determine the index of the RB starting from the first PRB set for hop 1. For this purpose, the frequency domain of the UE's active BWP can be changed as follows.

[0481]

[0482] Where, N BWP start,μ (0) indicates the lowest PRB index of the active BWP that has sent jump 0, while N BWP start,μ (1) Represents the lowest PRB index of the new active BWP used for hop 1 transfer. RB offset BWP N represents the gap between the lowest PRB index of the active BWP that has already sent hop 0 and the lowest PRB index of the new active BWP used to transmit hop 1. cell-BW size This represents the number of PRBs included in the cell. The RB indices starting from the first PRB set in hop 1 are as follows.

[0483] RB start (1) = RB start (0)

[0484] In other words, the RB index starting from the zeroth PRB set of hop 0 is the same as the RB index starting from the first PRB set of hop 1. However, since the active BWP sent for hop 0 and the active BWP sent for hop 1 are different, the two hops are sent at different frequencies. That is, if the RB index starting from the first PRB set of hop 1 is 0, this indicates the lowest PRB of the UE's new active BWP. In other words, the RB index starting from the first PRB set of hop 1 is interpreted as the index of the UE's new active BWP.

[0485] (4) Fourth embodiment

[0486] Figure 33 This is a diagram illustrating broadband frequency hopping according to an embodiment of the present disclosure.

[0487] refer to Figure 33 In the aforementioned third embodiment, the UE is based on the RB offset BWP The value moves the active BWP in the frequency domain. In the fourth embodiment, frequency hopping is enabled by sending hop 0 in the zeroth active BWP and changing hop 1 to the second active BWP. The UE can determine the zeroth PRB set of hop 0 via a DCI for scheduling PUSCH or a DCI / RRC signal for activating PUSCH. Here, the DCI for scheduling PUSCH or the DCI / RRC signal for activating PUSCH may include a Frequency Domain Resource Assignment (FDRA) field. The FDRA field may include the index of the RB starting at the zeroth PRB set of hop 0 and the number of consecutive RBs. Here, if the index of the RB starting at the zeroth PRB set of hop 0 is 0, this indicates the lowest PRB of the UE's active BWP. That is, the index of the RB starting at the zeroth PRB set of hop 0 is interpreted as the index of the UE's active BWP. The UE needs to determine the index of the RB starting at the first PRB set of hop 1. The UE may be instructed or configured with a second active BWP to determine the index of the RB starting at the first PRB set of hop 1. Here, the second active BWP may have a different frequency domain or subcarrier spacing than the active BWP that transmits hop 0. The UE can obtain the starting index of the first PRB set for hop 1 by interpreting the starting index of the previously obtained RB indicated by the FDRA field as the index of the second active BWP. The number of PRBs included in the first PRB set for hop 1 is equal to the number of PRBs included in the zeroth PRB set for hop 0.

[0488] In the first and second embodiments described above, the UE transmits channels and signals in a frequency band outside its RF bandwidth. In this case, the UE's RF needs to move from transmission in the previous frequency band to transmission in the new frequency band. The time used for this can be referred to as RF handover time. The UE needs sufficient RF handover time. That is, the base station should ensure that the UE has sufficient RF handover time.

[0489] RF switching time can be given in units of time. For example, RF switching time can be configured in x milliseconds (ms) or x microseconds (µs). Alternatively, RF switching time can be given as x samples. In this case, if the duration of a sample is expressed in Ts (seconds), its value is Ts = 1 / (Δf) ref ·N f,ref )), where Δf ref =15·10 3 Hz and N f,ref =2048. If the duration of a sample is expressed in seconds (Tc), then its value is Tc = 1 / ((Δf)). max ·N max )), where Δf max =480·10 3 N f =4096.

[0490] The duration can be configured differently for each frequency band. The UE can determine the number of symbols corresponding to a value given as a time unit. For example, if the given value is x ms, the UE can determine the number of symbols corresponding to x ms by dividing x ms by a symbol length (symbol_duration). That is, the number of symbols is x ms / symbol_duration. For reference, symbol_duration can be obtained as follows.

[0491] When using a normal CP, the length of an OFDM symbol can be different for each symbol. This is because the length of the cyclic prefix (CP) is different. More specifically, when using a normal CP, the CP length is as follows. If the OFDM symbol index in the subframe is 0 or 7*2... μ Therefore, the CP length is 144*κ*2. -μ +16*κ, and for the remaining OFDM symbol indices, the CP length is 144*κ*2. -μ Where μ is the subcarrier spacing configuration, it is 0 if the subcarrier spacing is 15KHz, 1 if the subcarrier spacing is 30KHz, 2 if the subcarrier spacing is 60KHz, and 3 if the subcarrier spacing is 120KHz. Furthermore, κ = Ts / Tc = 64.

[0492] The shorter length of the symbol length can be used as symbol_duration to obtain the number of symbols. That is, symbol_duration is 144 * κ * 2. -μ *Tc (seconds). The short length is used to obtain the minimum number of symbols needed to ensure RF switching time.

[0493] As another example, when transmitting an uplink channel, the UE can use different subsequent beams to perform the transmission in order to achieve beam diversity. In this case, the UE needs time to perform beam switching from the first beam to the second beam. This can be referred to as beam switching time. The UE should meet the beam switching time requirement. To this end, the base station can configure the time required for the UE's beam switching, similar to RF switching time, and the UE can determine the number of symbols required for the beam switching time.

[0494] In the following description of this disclosure, the number of symbols used to ensure RF handover time or beam switching time is denoted by G. For reference, if the UE needs to perform RF handover via frequency hopping and beam switching via beam changing, the value of G can be determined based on the sum or maximum value of the RF handover time or beam switching time. The UE cannot transmit uplink signals during the G-symbol period.

[0495] The objective of this disclosure is to provide a method for arranging G symbols that cannot be transmitted uplink signals / channels when transmitting uplink channels or signals. The method for this purpose is disclosed below.

[0496] Furthermore, for convenience, this disclosure will describe a method for arranging G symbols to meet the RF handover time between frequency hopping. This method can be interpreted as arranging G symbols to meet the beam switching time by replacing frequency hopping with beam changing.

[0497] Figure 34 The illustration shows the repeating type B of PUSCH according to the example.

[0498] refer to Figure 34 The UE is scheduled to repeat a PUSCH of length 4 (L=4) four times (K=4), starting from symbol 8 (S=8) in slot 0. Figure 34 As shown in (a), the UE can generate four nominal repeats by bundling each set of four symbols starting from symbol 8 in slot 0. Here, nominal repeat 0 includes symbols 8, 9, 10, and 11 in slot 0, nominal repeat 1 includes symbols 12 and 13 in slot 0 and symbols 0 and 1 in slot 1, nominal repeat 2 includes symbols 2, 3, 4, and 5 in slot 1, and nominal repeat 3 includes symbols 6, 7, 8, and 9 in slot 1.

[0499] like Figure 34As shown in (b), nominal repetitions are partitioned at the time slot boundaries (although not shown in the figure, this partitioning can occur around symbols invalid for UL transmission), consecutive symbols are combined within a time slot, and thus actual repetitions can be generated. Reference Figure 34 (b) Nominal repetition 1 can be divided into two actual repetitions. Therefore, the UE can send PUSCH using 5 actual repetitions. More specifically, actual repetition 0 includes symbols 8, 9, 10, and 11 of time slot 0, actual repetition 1 includes symbols 12 and 13 of time slot 0, actual repetition 2 includes symbols 0 and 1 of time slot 1, actual repetition 3 includes symbols 2, 3, 4, and 5 of time slot 1, and actual repetition 4 includes symbols 6, 7, 8, and 9 of time slot 1.

[0500] The accompanying figures show only the actual repeating indices. That is, if 0 is indicated, this shows the actual repeating of 0.

[0501] exist Figure 34 In this embodiment, the UE performs frequency hopping for each nominal repeat. That is, nominal repeats with even-numbered indices are transmitted in the zeroth PRB set of hop 0, and nominal repeats with odd-numbered indices are transmitted in the first PRB set of hop 1. For the sake of describing this disclosure, frequency hopping is described for each nominal repeat, but the scheme of this disclosure is applicable to other frequency hopping schemes.

[0502] The UE requires G symbols for RF handover during frequency hopping. That is, at least G symbols are needed between transmissions in the zeroth PRB set of hop 0 and transmissions in the first PRB set 1 of hop 1. A scheme for ensuring G symbols is disclosed. Figure 35 The first embodiment of PUSCH repeating type B is referenced in this disclosure.

[0503] Figure 35 A diagram illustrating the arrangement of gap symbols in a front nominal repeat of type BPUSH according to an embodiment of the present disclosure is shown.

[0504] refer to Figure 35 The UE may omit the PUSCH signal in the G symbols immediately preceding the frequency hopping and use these symbols as gaps. (See reference) Figure 35 (a) If G=1, the UE may not transmit PUSCH in the symbol immediately preceding the frequency hopping, and may use that symbol as a gap for RF handover. (See reference) Figure 35(b) If G = 2, the UE may not transmit PUSCH in the two symbols immediately preceding the frequency hopping and may use these symbols as gaps for RF handover. The frequency hopping occurs between nominal repetition 0 (symbols 8, 9, 10, and 11 of slot 0) and nominal repetition 1 (symbols 12 and 13 of slot 0 and symbols 0 and 1 of slot 1). Therefore, according to embodiments of this disclosure, the last G symbols of nominal repetition 0 immediately preceding the frequency hopping can be determined as symbols for which PUSCH is not transmitted. Thus, when an actual repetition is determined, symbols for which PUSCH is not transmitted can be excluded. (When an actual repetition is determined, symbols for which PUSCH is not transmitted can be determined as invalid symbols).

[0505] refer to Figure 35 (a) When G=1, symbol 11 of slot 0, symbol 1 of slot 1, and symbol 5 of slot 1 can be determined as symbols for which no PUSCH is transmitted. Therefore, the UE can configure actual repetition 0 by combining symbols 8, 9, and 10 of slot 0, actual repetition 1 by combining symbols 12 and 13 of slot 0, actual repetition 2 by combining symbols 2, 3, and 4 of slot 1, and actual repetition 3 by combining symbols 6, 7, 8, and 9 of slot 1. For reference, since symbol 0 of slot 1 is a single symbol, no PUSCH is transmitted. This symbol is referred to as an isolated symbol.

[0506] refer to Figure 35 (b) When G=2, symbols 10 and 11 of slot 0, symbols 0 and 1 of slot 1, and symbols 4 and 5 of slot 1 can be determined as symbols for which PUSCH is not transmitted. Therefore, the UE can configure actual repetition 0 by combining symbols 8 and 9 of slot 0, actual repetition 1 by combining symbols 12 and 13 of slot 0, actual repetition 2 by combining symbols 2 and 3 of slot 1, and actual repetition 3 by combining symbols 6, 7, 8, and 9 of slot 1.

[0507] A second embodiment of the PUSCH repeat type B disclosed herein, for example Figure 36 As shown.

[0508] Figure 36 A diagram illustrating gap symbols arranged in subsequent nominal repetitions of type BPUSHCH repetitions according to an embodiment of the present disclosure is shown.

[0509] refer to Figure 36 The UE may omit the PUSCH transmission in the G symbols immediately following the frequency hopping and use these symbols as gaps for RF handover. (See reference) Figure 36 (a) If G=1, the UE may not transmit PUSCH in the symbol immediately following the frequency hopping, and may use that symbol as a gap for RF handover. (See reference) Figure 36 (b) If G = 2, the UE may not transmit PUSCH in the two symbols immediately following the frequency hopping, and may use these symbols as gaps for RF handover. The frequency hopping occurs between nominal repetition 0 (symbols 8, 9, 10, and 11 of slot 0) and nominal repetition 1 (symbols 12 and 13 of slot 0 and symbols 0 and 1 of slot 1). Therefore, according to embodiments of this disclosure, the first G symbols of nominal repetition 1 immediately following the frequency hopping can be determined as symbols for which PUSCH is not transmitted. Thus, when an actual repetition is determined, symbols for which PUSCH is not transmitted can be excluded. (When an actual repetition is determined, symbols for which PUSCH is not transmitted can be determined as invalid symbols).

[0510] refer to Figure 36 (a) When G=1, symbols 12 of slot 0, 2 of slot 1, and 6 of slot 1 can be determined as symbols for which no PUSCH is transmitted. Therefore, the UE can configure actual repetition 0 by combining symbols 8, 9, 10, and 11 of slot 0, actual repetition 1 by combining symbols 0 and 1 of slot 1, actual repetition 2 by combining symbols 3, 4, and 5 of slot 1, and actual repetition 3 by combining symbols 7, 8, and 9 of slot 1. For reference, since symbol 13 of slot 0 is a single symbol, no PUSCH is transmitted. This symbol is referred to as an isolated symbol.

[0511] refer to Figure 36 (b) When G=2, symbols 12 and 13 of slot 0, symbols 2 and 3 of slot 1, and symbols 6 and 7 of slot 1 can be determined as symbols for which PUSCH is not transmitted. Therefore, the UE can configure actual repetition 0 by combining symbols 8, 9, 10, and 11 of slot 0, actual repetition 1 by combining symbols 0 and 1 of slot 1, actual repetition 2 by combining symbols 4 and 5 of slot 1, and actual repetition 3 by combining symbols 8 and 9 of slot 1.

[0512] Compared to the first embodiment, the second embodiment has the following advantages. When low latency is required, such as in URLLC systems, it is preferable to transmit the PUSCH in as many early (time-advanced) symbols as possible. When comparing the number of symbols included in the first actual repetition of the first embodiment and the number of symbols included in the first actual repetition of the second embodiment, more symbols can be used to transmit the PUSCH since there are no symbols used as gaps in the second embodiment. Therefore, the base station has a high probability of correctly receiving the PUSCH at an earlier time point.

[0513] However, in the first and second embodiments, G symbols are not used for PUSCH transmission in a nominal repetition, thus the repetition has a different number of symbols. For example, in Figure 35In (b), repetitions 0, 1, and 2 actually occupy 2 symbols, but repetition 3 actually occupies 4 symbols. Therefore, PUSCH reception performance may be degraded due to the difference in the number of symbols between repetitions.

[0514] The third implementation of the PUSCH repeat type B of this disclosure, for example Figure 37 As shown.

[0515] Figure 37 This is a diagram illustrating the distribution of gap symbols in type B PUSCH repetitions according to an embodiment of the present disclosure.

[0516] refer to Figure 37 The UE may not transmit PUSCH in the f(G / 2) symbols immediately preceding the frequency hopping, and may not transmit PUSCH in the Gf(G / 2) symbols immediately following the frequency hopping. f(G / 2) is at least one of floor(G / 2), ceil(G / 2), and round(G / 2). That is, in the third embodiment, the difference in the number of symbols between repetitions can be reduced by not using the same number of symbols available for the nominal repetition immediately preceding and immediately following the frequency hopping for PUSCH transmission.

[0517] refer to Figure 37 When G=2, symbols 11 and 12 of slot 0, symbols 1 and 2 of slot 1, and symbols 5 and 6 of slot 1 can be determined as symbols for which PUSCH is not transmitted. Therefore, the UE can configure actual repetition 0 by combining symbols 8, 9, and 10 of slot 0, actual repetition 1 by combining symbols 3 and 4 of slot 1, and actual repetition 2 by combining symbols 7, 8, and 9 of slot 1. For reference, since symbol 13 of slot 0 is one symbol, PUSCH is not transmitted. Additionally, since symbol 0 of slot 1 is one symbol, PUSCH is not transmitted.

[0518] refer to Figure 37 According to the third embodiment, it can be identified that the number of symbols repeated in each iteration of the UE is similar. Figure 37 In the original text, the actual repetition of 0 and 2 occupies 3 symbols, and the actual repetition of 1 occupies 2 symbols. However, in... Figure 37 In this configuration, symbol 13 in slot 0 and symbol 0 in slot 1 are isolated symbols that are not used for PUSCH. Therefore, the total number of symbols used for PUSCH is reduced. A method to address this issue is needed.

[0519] As a fourth embodiment of PUSCH repetition type B of the present disclosure, the UE may compare the number of symbols of the actual repetition immediately before frequency hopping with the number of symbols of the actual repetition immediately after frequency hopping to determine G symbols for which the PUSCH is not transmitted. Here, first, in the actual repetition with a larger number of symbols, some or all of the symbols may be determined as symbols for which the PUSCH is not transmitted. The specific method is as follows.

[0520] As a first method, the UE compares the number of symbols of the actual repetition immediately before frequency hopping with the number of symbols of the actual repetition immediately after frequency hopping to determine G symbols for which the PUSCH is not transmitted in the actual repetition with a larger number of symbols. Here, when the number of symbols of the actual repetition immediately before frequency hopping is N1 and the number of symbols of the actual repetition immediately after frequency hopping is N2, the G symbols can be determined as follows.

[0521] - If N1 ≥ N2, the last G symbols of the actual repetition immediately before frequency hopping are determined as symbols for which the PUSCH is not transmitted.

[0522] - If N1 < N2, the first G symbols of the actual repetition immediately after frequency hopping are determined as symbols for which the PUSCH is not transmitted.

[0523] As a second method, the UE compares the number of symbols of the actual repetition immediately before frequency hopping (N1) with the number of symbols of the actual repetition immediately after frequency hopping (N2) to determine one symbol as a symbol for which the PUSCH is not transmitted in the actual repetition with a larger number of symbols. If the actual repetition is the actual repetition immediately before frequency hopping, the one symbol is the last symbol of the actual repetition, and if the actual repetition is the actual repetition immediately after frequency hopping, the one symbol is the first symbol of the actual repetition. Repeat this operation until G symbols are obtained. More specifically, the G symbols are obtained as follows.

[0524] - Assume g1 = 0 and g2 = 0.

[0525] - If g1 + g2 < G, repeat the following process. If N1 - g1 ≥ N2 - g2, then g1 = g1 + 1. If N1 - g1 < N2 - g2, then g2 = g2 + 1.

[0526] - The last g1 symbols of the actual repetition immediately before frequency hopping are determined as symbols for which the PUSCH is not transmitted.

[0527] - The first g2 symbols of the actual repetition immediately after frequency hopping are determined as symbols for which the PUSCH is not transmitted.

[0528] As another third method, the G symbols can be determined as follows.

[0529] - If N1 ≥ N2 and N1 - N2 ≥ G, the last G symbols of the actual repetition immediately before frequency hopping are determined as symbols not transmitting PUSCH.

[0530] - If N1 ≥ N2 and N1 - N2 < G, the last N1 - N2 + f((G - (N1 - N2)) / 2) symbols of the actual repetition immediately before frequency hopping are determined as symbols not transmitting PUSCH, and the first G - (N1 - N2) - f((G - (N1 - N2)) / 2) symbols of the actual repetition immediately after frequency hopping are determined as symbols not transmitting PUSCH.

[0531] - If N1 < N2 and N2 - N1 ≥ G, the first G symbols of the actual repetition immediately after frequency hopping are determined as symbols not transmitting PUSCH.

[0532] - If N1 < N2 and N2 - N1 < G, the last G - (N2 - N1) - f((G - (N2 - N1)) / 2) symbols of the actual repetition immediately before frequency hopping are determined as symbols not transmitting PUSCH, and the first N2 - N1 + f((G - (N2 - N1)) / 2) symbols of the actual repetition immediately after frequency hopping are determined as symbols not transmitting PUSCH.

[0533] The fourth embodiment of PUSCH repetition type B of the present disclosure is as Figure 38 shown.

[0534] Figure 38 Shows a diagram illustrating that gap symbols according to an embodiment of the present disclosure are arranged in a nominal repetition having a large number of symbols in type B PUSCH repetition.

[0535] According to the first method, the UE determines the symbols not transmitting PUSCH as follows. First, the UE assumes G = 0 (ignoring the gap) and obtains the actual repetition. Here, the obtained actual repetition is as Figure 34 (b) shown. Here, the obtained actual repetition is an intermediate process and, for convenience, is referred to as the intermediate actual repetition, and the actual repetition according to the actual transmission of the symbols not transmitting PUSCH is obtained as follows.

[0536] According to Figure 34(b) There are five intermediate actual repetitions, with indices 0, 1, 2, 3, and 4. Frequency hopping occurs between intermediate actual repetitions 0 and 1, between intermediate actual repetitions 2 and 3, and between intermediate actual repetitions 3 and 4. First, determine the earliest hopping interval in time. Intermediate actual repetition 0 includes 4 symbols, and intermediate actual repetition 1 includes 2 symbols. Therefore, the last G symbols of intermediate actual repetition 0, which includes more symbols, are determined as symbols for which PUSCH is not sent. Determine the next earliest hopping interval in time. Intermediate actual repetition 2 includes 2 symbols, and intermediate actual repetition 3 includes 4 symbols. Therefore, the first G symbols of intermediate actual repetition 3, which includes more symbols, are determined as symbols for which PUSCH is not sent. Finally, determine the latest hopping interval in time. Intermediate actual repetition 3 includes 3 symbols (when G=1, refer to...). Figure 38 (a) or 2 symbols (when G=2, see reference) Figure 38 (b)), and the intermediate actual repetition 4 includes 4 symbols. Therefore, the first G symbols of the intermediate actual repetition 4, which includes more symbols, are determined to be symbols for which PUSCH is not sent. The UE can determine the actual repetition by excluding the determined symbols for which PUSCH is not sent from the intermediate actual repetition.

[0537] According to the fourth embodiment of PUSCH repetition type B of this disclosure, some symbols in an actual repetition with a longer length are determined to be symbols that do not transmit PUSCH. Therefore, the overall length of the actual repetition is reduced. Consequently, an actual repetition cannot have a low code rate. A method is needed to solve this problem.

[0538] As a fifth embodiment of PUSCH repetition type B of this disclosure, the UE can compare the number of actual repetitions immediately before frequency hopping with the number of actual repetitions immediately after frequency hopping to determine G symbols that do not transmit PUSCH. Here, firstly, in the actual repetitions with a smaller number of symbols, some or all of the symbols can be determined as symbols that do not transmit PUSCH. The specific method is as follows.

[0539] As a first method, the UE compares the number of actual repeating symbols immediately before the frequency hopping with the number of actual repeating symbols immediately after the frequency hopping, so as to determine G symbols that are not transmitting PUSCH from the actual repeating symbols with a smaller number of symbols. Here, when the number of actual repeating symbols immediately before the frequency hopping is N1 and the number of actual repeating symbols immediately after the frequency hopping is N2, the G symbols can be determined as follows.

[0540] - If N1≥N2, then the first G symbols of the actual repetition immediately following the frequency hopping are determined as symbols for which PUSCH is not sent.

[0541] If N1 < N2, the last G symbols of the actual repetition immediately before the frequency hopping are determined as the symbols for not transmitting PUSCH.

[0542] - As a second method, the UE compares the number of symbols (N1) of the actual repetition immediately before the frequency hopping with the number of symbols (N2) of the actual repetition immediately after the frequency hopping, so as to determine, in the actual repetition with a smaller number of symbols, a symbol as the symbol for not transmitting PUSCH. If the actual repetition is the actual repetition immediately before the frequency hopping, the symbol is the last symbol of the actual repetition, and if the actual repetition is the actual repetition immediately after the frequency hopping, the symbol is the first symbol of the actual repetition. Repeat this operation until G symbols are obtained. More specifically, G symbols are obtained as follows.

[0543] - Assume g1 = 0 and g2 = 0.

[0544] - If g1 + g2 < G, repeat the following process. If N1 - g1 ≥ N2 - g2, then g2 = g2 + 1. If N1 - g1 < N2 - g2, then g1 = g1 + 1.

[0545] - The last g1 symbols of the actual repetition immediately before the frequency hopping are determined as the symbols for not transmitting PUSCH.

[0546] - The first g2 symbols of the actual repetition immediately after the frequency hopping are determined as the symbols for not transmitting PUSCH.

[0547] As another third method, G symbols can be determined as follows.

[0548] - If N1 ≥ N2 and N2 ≥ G, the first G symbols of the actual repetition immediately after the frequency hopping are determined as the symbols for not transmitting PUSCH.

[0549] - If N1 ≥ N2 and N2 < G, all N2 symbols of the actual repetition immediately after the frequency hopping are determined as the symbols for not transmitting PUSCH, and the last G - N2 symbols of the actual repetition immediately before the frequency hopping are determined as the symbols for not transmitting PUSCH.

[0550] - If N1 < N2 and N1 ≥ G, the last G symbols of the actual repetition immediately before the frequency hopping are determined as the symbols for not transmitting PUSCH.

[0551] - If N1 < N2 and N1 < G, all N1 symbols of the actual repetition immediately before the frequency hopping are determined as the symbols for not transmitting PUSCH, and the first G - N1 symbols of the actual repetition immediately after the frequency hopping are determined as the symbols for not transmitting PUSCH.

[0552] The fifth implementation of the PUSCH repeat type B of this disclosure, for example Figure 39 As shown.

[0553] Figure 39 A diagram illustrating gap symbols arranged in a nominal repeat of type BPUSHCH with a small number of symbols, according to an embodiment of the present disclosure, is shown.

[0554] According to the first method, the UE determines the symbols for which PUSCH is not transmitted as follows. First, the UE assumes G = 0 (ignoring gaps) and obtains the actual repetition. Here, the obtained actual repetition is as follows: Figure 34 As shown in (b). Here, the actual repetition obtained is an intermediate process, and for convenience, it is called intermediate actual repetition, and the actual repetition of actual transmission based on the symbols for which PUSCH is not sent is obtained as follows.

[0555] according to Figure 34 (b) There are five intermediate actual repetitions, with indices 0, 1, 2, 3, and 4. Frequency hopping occurs between intermediate actual repetitions 0 and 1, between intermediate actual repetitions 2 and 3, and between intermediate actual repetitions 3 and 4. First, determine the earliest time-based frequency hopping interval. Intermediate actual repetition 0 comprises 4 symbols, and intermediate actual repetition 1 comprises 2 symbols. Therefore, the first G symbols of intermediate actual repetition 1, which comprises fewer symbols, are determined as symbols for which PUSCH is not sent. Determine the next earliest time-based frequency hopping interval. Intermediate actual repetition 2 comprises 2 symbols, and intermediate actual repetition 3 comprises 4 symbols. Therefore, the last G symbols of intermediate actual repetition 2, which comprises fewer symbols, are determined as symbols for which PUSCH is not sent. Finally, determine the latest time-based frequency hopping interval. Intermediate actual repetition 3 comprises 4 symbols, and intermediate actual repetition 4 comprises 4 symbols. Therefore, since intermediate actual repetitions 3 and 4 have the same number of symbols, the last G symbols of the preceding intermediate actual repetition 3 are determined to be symbols that do not send PUSCH. The UE can determine the actual repetition by excluding the determined symbols that do not send PUSCH from the intermediate actual repetitions. For reference, when G=1, each of intermediate actual repetitions 1 and 2 includes one symbol. Therefore, this one symbol is an isolated symbol that does not send PUSCH.

[0556] refer to Figure 39 This allows us to identify PUSCHs sent by the UE that actually repeat with more symbols. However, according to Figure 39 (a) If G symbols are unavailable for PUSCH transmission in an intermediate actual repetition that includes a small number of symbols, there may be a surplus symbol as an isolated symbol. This isolation reduces the total number of symbols available for PUSCH transmission. A method is needed to address this issue.

[0557] As a sixth embodiment of PUSCH repetition type B of the present disclosure, the UE may compare the number of symbols of the actual repetition immediately before frequency hopping with the number of symbols of the actual repetition immediately after frequency hopping to determine G symbols for which the PUSCH is not transmitted. Here, first, in the actual repetition with a smaller number of symbols, some or all of the symbols may be determined as symbols for which the PUSCH is not transmitted. However, if the actual repetition has 2 symbols, no symbols for which the PUSCH is not transmitted may be determined in the corresponding actual repetition, and symbols for which the PUSCH is not transmitted may be determined in the actual repetition with more symbols. The specific method is as follows.

[0558] As a first method, the UE compares the number of symbols of the actual repetition immediately before frequency hopping with the number of symbols of the actual repetition immediately after frequency hopping to determine that G symbols in the actual repetition with a smaller number of symbols are symbols for which the PUSCH is not transmitted. Here, when the number of symbols of the actual repetition immediately before frequency hopping is N1 and the number of symbols of the actual repetition immediately after frequency hopping is N2, the G symbols may be determined as follows.

[0559] - If N1 ≥ N2 and N2 - G ≥ 2, the first G symbols of the actual repetition immediately after frequency hopping are determined as symbols for which the PUSCH is not transmitted.

[0560] - If N1 ≥ N2 and N2 - G < 2, the first N2 - 2 symbols of the actual repetition immediately after frequency hopping are determined as symbols for which the PUSCH is not transmitted. The last G - (N2 - 2) symbols of the actual repetition immediately before frequency hopping are determined as symbols for which the PUSCH is not transmitted.

[0561] - If N1 < N2 and N1 - G ≥ 2, the last G symbols of the actual repetition immediately before frequency hopping are determined as symbols for which the PUSCH is not transmitted.

[0562] - If N1 < N2 and N1 - G < 2, the last N1 - 2 symbols of the actual repetition immediately before frequency hopping are determined as symbols for which the PUSCH is not transmitted, and the first G - (N1 - 2) symbols of the actual repetition immediately after frequency hopping are determined as symbols for which the PUSCH is not transmitted.

[0563] As a second method, the UE compares the number of actually repeated symbols (N1) immediately before the frequency hopping with the number of actually repeated symbols (N2) immediately after the frequency hopping, so as to determine a symbol that does not transmit PUSCH in the actual repetition with a smaller number of symbols. If the actual repetition is the actual repetition immediately before the frequency hopping, the symbol is the last symbol of the actual repetition, and if the actual repetition is the actual repetition immediately after the frequency hopping, the symbol is the first symbol of the actual repetition. Repeat this operation until G symbols are obtained. More specifically, G symbols are obtained as follows.

[0564] - Assume g1 = 0 and g2 = 0.

[0565] - If g1 + g2 < G, repeat the following process. If N1 - g1 ≥ N2 - g2 ≥ 2, then g2 = g2 + 1. Otherwise, g1 = g1 + 1.

[0566] - The last g1 symbols of the actual repetition immediately before the frequency hopping are determined as symbols that do not transmit PUSCH.

[0567] - The first g2 symbols of the actual repetition immediately after the frequency hopping are determined as symbols that do not transmit PUSCH.

[0568] As another third method, G symbols can be determined as follows.

[0569] - If N1 ≥ N2 and N2 - G ≥ 2, the first G symbols of the actual repetition immediately after the frequency hopping are determined as symbols that do not transmit PUSCH

[0570] - If N1 ≥ N2 and N2 - G < 2, the first N2 - 2 symbols of the actual repetition immediately after the frequency hopping are determined as symbols that do not transmit PUSCH, and the last G - (N2 - 2) symbols of the actual repetition immediately before the frequency hopping are determined as symbols that do not transmit PUSCH.

[0571] - If N1 < N2 and N1 - G ≥ 2, the last G symbols of the actual repetition immediately before the frequency hopping are determined as symbols that do not transmit PUSCH.

[0572] - If N1 < N2 and N1 - G < 2, the N1 - 2 symbols of the actual repetition immediately before the frequency hopping are determined as symbols that do not transmit PUSCH, and the first G - (N1 - 2) symbols of the actual repetition immediately after the frequency hopping are determined as symbols that do not transmit PUSCH.

[0573] The sixth embodiment of PUSCH repetition type B of the present disclosure is as Figure 40 shown.

[0574] Figure 40A diagram illustrating the arrangement of gap symbols in an embodiment of this disclosure is shown so that isolated symbols do not appear in type B PUSCH repetitions.

[0575] According to the first method, the UE determines the symbols for which PUSCH is not transmitted as follows. First, the UE assumes G = 0 (ignoring gaps) and obtains the actual repetition. Here, the obtained actual repetition is as follows: Figure 34 As shown in (b). Here, the actual repetition obtained is an intermediate process, and for convenience, it is called intermediate actual repetition, and the actual repetition of actual transmission based on the symbols for which PUSCH is not sent is obtained as follows.

[0576] according to Figure 34 (b) There are five intermediate actual repetitions, with indices 0, 1, 2, 3, and 4. Frequency hopping occurs between intermediate actual repetitions 0 and 1, between intermediate actual repetitions 2 and 3, and between intermediate actual repetitions 3 and 4. First, determine the earliest frequency hopping interval in time. Intermediate actual repetition 0 contains 4 symbols, and intermediate actual repetition 1 contains 2 symbols. Therefore, since intermediate actual repetition 1, which contains fewer symbols, contains 2 symbols, this intermediate actual repetition can no longer include symbols that do not send PUSCH (if included, it generates an isolated symbol). Therefore, the last G symbols of intermediate actual repetition 0, which contains more symbols, are determined to be symbols that do not send PUSCH. Determine the next earliest frequency hopping interval in time. Intermediate actual repetition 2 contains 2 symbols, and intermediate actual repetition 3 contains 4 symbols. Since intermediate actual repetition 2, which contains fewer symbols, contains 2 symbols, this intermediate actual repetition can no longer include symbols that do not send PUSCH (if included, it generates an isolated symbol). Therefore, the last G symbols of the intermediate actual repetition 3, including more symbols, are determined as symbols for which PUSCH is not transmitted. Finally, the time interval of the most recent frequency hopping is determined. The intermediate actual repetition 3 includes 3 symbols (when... Figure 40 (a) when G=1) or 2 symbols (when Figure 40 (b) When G=2), and the actual repetition of 4 in the middle includes 4 symbols. If the actual repetition of 3 in the middle includes 3 symbols (when... Figure 40 (a) When G=1, the last G=1 symbols of the intermediate actual repetition 3 are determined to be symbols for which PUSCH is not sent. If the intermediate actual repetition 3 includes 2 symbols (when...) Figure 40 (b) When G=2, the first G=2 symbols of the actual repetition of 4 in the middle are determined as symbols that do not send PUSCH.

[0577] refer to Figure 40 It can identify that there are no longer isolated symbols in the actual repetitions sent by the UE.

[0578] In the first to sixth embodiments of PUSCH repetition type B disclosed herein, some or all symbols in the obtained nominal or actual repetitions are determined to be symbols that will not transmit PUSCH. However, in this case, the number of symbols actually used by the UE for PUSCH transmission is reduced. Therefore, the reliability of PUSCH transmission may be reduced. A solution to this problem is needed.

[0579] According to the seventh embodiment of PUSCH repetition type B of this disclosure, the UE can consider G symbols to determine the nominal repetition. More specifically, to determine the nominal repetition, the UE is informed or configured by the base station with the value of the starting symbol index (S) of the first nominal repetition, the number of symbols included in the nominal repetition (L), and the number of nominal repetitions (K). The UE obtains the first nominal repetition by combining L symbols starting from the starting symbol index (S) of the first nominal repetition. Then, the UE obtains the second nominal repetition by combining L symbols starting from the subsequent symbols. In this way, K nominal repetitions are generated.

[0580] If the UE cannot transmit PUSCH within G symbols between frequency hopping intervals, the UE can determine nominal repetitions as follows: The UE obtains a first nominal repetition by combining L symbols starting from the start symbol index (S) of the first nominal repetition. The UE determines G symbols starting from the symbols following the first nominal repetition as symbols for which PUSCH will not be transmitted. Then, the UE performs a second nominal repetition by combining L symbols starting from the subsequent symbols. The UE determines G symbols starting from the symbols following the first nominal repetition as symbols for which PUSCH will not be transmitted. In this way, K nominal repetitions are generated.

[0581] Figure 41 A diagram illustrating the addition of a gap symbol after the nominal repetition in a type B PUSCH repeat according to an embodiment of the present disclosure is shown.

[0582] refer to Figure 41 (a) S=8, L=4, K=4, G=1. The UE obtains the first nominal repetition by combining symbols 8, 9, 10, and 11 of time slot 0. The UE determines the subsequent G=1 symbol (symbol 12 of time slot 0) as a symbol for which no PUSCH is transmitted. Then, the UE obtains the second nominal repetition by combining symbol 13 of time slot 0 and symbols 0, 1, and 2 of time slot 1. The UE determines the subsequent G=1 symbol (symbol 3 of time slot 1) as a symbol for which no PUSCH is transmitted. Then, the UE obtains the third nominal repetition by combining symbols 4, 5, 6, and 7 of time slot 1. The UE determines the subsequent G=1 symbol (symbol 8 of time slot 1) as a symbol for which no PUSCH is transmitted. Finally, the UE obtains the fourth nominal repetition by combining symbols 9, 10, 11, and 12 of time slot 1. The nominal repetitions obtained in this way can be classified as actual repetitions.

[0583] refer to Figure 41 (b) S = 8, L = 4, K = 4, and G = 2. The UE generates a first nominal repetition by combining symbols 8, 9, 10, and 11 of time slot 0. The UE determines the subsequent G = 2 symbols (symbols 12 and 13 of time slot 0) as symbols for which no PUSCH is transmitted. Then, the UE obtains a second nominal repetition by combining symbols 0, 1, 2, and 3 of time slot 1. The UE determines the subsequent G = 2 symbols (symbols 4 and 5 of time slot 1) as symbols for which no PUSCH is transmitted. Then, the UE generates a third nominal repetition by combining symbols 6, 7, 8, and 9 of time slot 1. The UE determines the subsequent G = 2 symbols (symbols 10 and 11 of time slot 1) as symbols for which no PUSCH is transmitted. Finally, the UE obtains a fourth nominal repetition by combining symbols 12 and 13 of time slot 1 and symbols 0 and 1 of time slot 2. The nominal repetitions obtained in this way can be classified as actual repetitions.

[0584] In the seventh embodiment of PUSCH repetition type B disclosed herein, symbols for which PUSCH is not transmitted are inserted between nominal repetitions. However, some symbols in a nominal repetition may not be transmitted. For example, invalid UL symbols (DL symbols, SSB symbols, CORESET#0 symbols, and symbols configured via RRC signals) may not be transmitted. Additionally, if a consecutive symbol exists in a time slot within a nominal repetition, that symbol is an isolated symbol and is therefore not transmitted. Therefore, it is not always necessary to insert symbols for which PUSCH is not transmitted between nominal repetitions. Embodiments for addressing this problem are disclosed below.

[0585] In the eighth embodiment of PUSCH repetition type B of this disclosure, the UE can determine nominal repetition and actual repetition by considering G symbols, invalid UL symbols, and isolated symbols. More specifically, if the UE cannot transmit PUSCH within G symbols between frequency hopping sessions, the UE can determine a first nominal repetition. The UE performs the first nominal repetition by combining L symbols starting from the start symbol index (S) of the first nominal repetition. The UE obtains the actual repetition from the first nominal repetition. In addition, the UE determines the G symbols after the last symbol of the actual repetition as symbols for which PUSCH is not transmitted. Then, the UE can determine a second nominal repetition by combining the L symbols after the G symbols. The UE obtains the actual repetition from the second nominal repetition. The UE determines the G symbols after the last symbol of the obtained actual repetition as symbols for which PUSCH is not transmitted. In this way, the UE obtains K nominal repetitions and obtains the actual repetition from the K nominal repetitions.

[0586] Figure 42 A diagram illustrating the gap symbols of invalid UL symbols and isolated symbols in a contemplated type B PUSCH repetition according to an embodiment of this disclosure is shown.

[0587] refer to Figure 42 (a) S=8, L=4, K=4, and G=1. The UE obtains a first nominal repetition by combining symbols 8, 9, 10, and 11 of slot 0. An actual repetition is obtained from the first nominal repetition. This actual repetition includes symbols 8, 9, 10, and 11 of slot 0. The UE determines the subsequent G=1 symbol (symbol 12 of slot 0) as a symbol for which no PUSCH is transmitted. Then, the UE obtains a second nominal repetition by combining symbol 13 of slot 0 and symbols 0, 1, and 2 of slot 1. An actual repetition is obtained from the second nominal repetition. This actual repetition includes symbols 0 and 1 of slot 1. For reference, symbol 13 of slot 0 is an isolated symbol and is therefore excluded from the actual repetition, and symbol 2 of slot 1 is an invalid UL symbol and is therefore excluded from the actual repetition. Therefore, the last symbol of the actual repetition is symbol 1 of slot 1. The G=1 symbol following this symbol (symbol 2 of slot 1) is determined as a symbol for which no PUSCH is transmitted. In this way, the UE obtains K=4 nominal repetitions and obtains the actual repetitions from K=4 nominal repetitions.

[0588] refer to Figure 42 (b) S = 8, L = 4, K = 4, and G = 2. The UE obtains the first nominal repetition by combining symbols 8, 9, 10, and 11 of slot 0. The actual repetition is obtained from the first nominal repetition. This actual repetition includes symbols 8, 9, 10, and 11 of slot 0. The UE determines the subsequent G = 2 symbols (symbols 12 and 13 of slot 0) as symbols for which PUSCH will not be transmitted. Then, the UE obtains the second nominal repetition by combining symbols 0, 1, 2, and 3 of slot 1. The actual repetition is obtained from the second nominal repetition. This actual repetition includes symbols 0 and 1 of slot 1. For reference, symbol 2 of slot 1 is an invalid UL symbol and is therefore excluded from the actual repetition. Furthermore, symbol 3 of slot 1 is an isolated symbol and is therefore excluded from the actual repetition. Therefore, the last symbol of the actual repetition is symbol 1 of slot 1. The G = 2 symbols following this symbol (symbols 2 and 3 of slot 1) are determined as symbols for which PUSCH will not be transmitted. In this way, the UE obtains K=4 nominal repetitions and obtains the actual repetitions from K=4 nominal repetitions.

[0589] The present disclosure has been described above by way of example, and those skilled in the art to which this disclosure pertains will understand that it can be readily modified into other specific forms without altering its technical spirit or essential characteristics. Therefore, it should be understood that the above embodiments are illustrative and not intended to limit the present disclosure in all respects. For example, each element described in a single form may be implemented in a distributed form, and similarly, elements described in a distributed form may be implemented in a combined form.

[0590] The scope of this disclosure is indicated by the claims, which will be described later, rather than by a detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents shall be construed as being included within the scope of this disclosure.

Claims

1. A user equipment (UE) for use in a wireless communication system based on the 3rd Generation Partnership Project (3GPP), the UE comprising: Communication module; as well as Processor, wherein the processor is configured to: Receive a system information block (SIB) that includes information for cell access, the information being associated with at least the following: - The configuration of the first random access channel (RACH) associated with the first uplink bandwidth portion (UL BWP) for a normal UE, and - A second UL BWP for reducing the capability (RedCap) of a UE; and Based on whether the UE corresponds to the RedCap UE, a random access (RA) preamble is transmitted via one of the first UL BWP and the second UL BWP. Wherein, if the UE receives a second RACH configuration for the second UL BWP, the second RACH configuration is used for the RA preamble transmission in the second UL BWP, and If the UE does not receive the second RACH configuration for the second UL BWP, then the first RACH configuration for the first UL BWP is used for the RA preamble transmission in the second UL BWP.

2. The UE according to claim 1, wherein, In association with the RA preamble, a physical downlink control channel (PDCCH) for scheduling random access response (RAR) is received.

3. The UE according to claim 2, wherein, Regardless of where the RA preamble is transmitted between the first UL BWP and the second UL BWP, the same equation is used to obtain the RA-Radio Network Temporary Identifier (RA-RNTI) associated with the PDCCH used for scheduling the RAR, and Specifically, based on the position of the RA preamble in the first UL BWP and the second UL BWP, the PDCCH for scheduling the RAR is received via a corresponding initial DL BWP among a plurality of initial DL BWPs.

4. The UE according to claim 3, wherein, The RA preamble is sent at the RACH timing, and the equation includes: RA-RNTI = 1 + s_id + 14 × t_id + 14 × 80 × f_id + 14 × 80 × 8 × ul_carrier_id, where, -s_id represents the index of the first symbol of the RACH timing. -t_id represents the index of the first slot of the RACH timing in the system frame. -f_id represents the index of the RACH timing in the frequency domain, and -ul_carrier_id indicates the UL carrier type for transmitting the RA preamble.

5. The UE according to claim 1, wherein, The SIB further receives an indicator, which indicates whether the UE is allowed to access the cell when the UE is the RedCap UE.

6. A method used by a user equipment (UE) in a 3GPP-based wireless communication system, the method comprising: Receive a system information block (SIB) that includes information for cell access, the information being associated with at least the following: - The configuration of the first random access channel (RACH) associated with the first uplink bandwidth portion (UL BWP) for a normal UE, and - A second UL BWP for reducing the capability (RedCap) of a UE; as well as Based on whether the UE corresponds to the RedCap UE, a random access (RA) preamble is transmitted via one of the first UL BWP and the second UL BWP. Wherein, if the UE receives a second RACH configuration for the second UL BWP, the second RACH configuration is used for the RA preamble transmission in the second UL BWP, and If the UE does not receive the second RACH configuration for the second UL BWP, then the first RACH configuration for the first UL BWP is used for the RA preamble transmission in the second UL BWP.

7. The method according to claim 6, wherein, In association with the RA preamble, a physical downlink control channel (PDCCH) for scheduling random access response (RAR) is received.

8. The method according to claim 7, wherein, Regardless of where the RA preamble is transmitted between the first UL BWP and the second UL BWP, the same equation is used to obtain the RA-Radio Network Temporary Identifier (RA-RNTI) associated with the PDCCH used for scheduling the RAR, and Specifically, based on the position of the RA preamble in the first UL BWP and the second UL BWP, the PDCCH for scheduling the RAR is received via a corresponding initial DL BWP among a plurality of initial DL BWPs.

9. The method according to claim 8, wherein, The RA preamble is sent at the RACH timing, and the equation includes: RA-RNTI = 1 + s_id + 14 × t_id + 14 × 80 × f_id + 14 × 80 × 8 × ul_carrier_id, where, -s_id represents the index of the first symbol of the RACH timing. -t_id represents the index of the first slot of the RACH timing in the system frame. -f_id represents the index of the RACH timing in the frequency domain, and -ul_carrier_id indicates the UL carrier type for transmitting the RA preamble.

10. The method according to claim 6, wherein, The SIB further receives an indicator, which indicates whether the UE is allowed to access the cell when the UE is the RedCap UE.

11. A base station (BS) for use in a 3GPP-based wireless communication system, the BS comprising: Communication module; as well as Processor, wherein the processor is configured to: Sending a System Information Block (SIB) that includes information for cell access, the information being associated with at least the following: - The configuration of the first random access channel (RACH) associated with the first uplink bandwidth portion (UL BWP) for a normal UE, and - A second UL BWP for reducing the capability (RedCap) of a UE; and Receive random access (RA) preamble via one of the first UL BWP and the second UL BWP. Wherein, if the second RACH configuration for the second UL BWP is broadcast, the second RACH configuration is used for RA preamble reception in the second UL BWP, and If the second RACH configuration used for the second UL BWP is not broadcast, then the first RACH configuration used for the first UL BWP is used for RA preamble reception in the second UL BWP.

12. The BS according to claim 11, wherein, In association with the RA preamble, a physical downlink control channel (PDCCH) for scheduling random access response (RAR) is transmitted.

13. The BS according to claim 12, wherein, Regardless of where the RA preamble is received between the first UL BWP and the second UL BWP, the same equation is used to obtain the RA-Radio Network Temporary Identifier (RA-RNTI) associated with the PDCCH used for scheduling the RAR, and Specifically, based on the position of the RA preamble between the first UL BWP and the second UL BWP, the PDCCH for scheduling the RAR is sent via a corresponding initial DL BWP among a plurality of initial DL BWPs.

14. The BS according to claim 13, wherein, The RA preamble is received at the RACH timing, and the equation includes: RA-RNTI = 1 + s_id + 14 × t_id + 14 × 80 × f_id + 14 × 80 × 8 × ul_carrier_id, where, -s_id represents the index of the first symbol of the RACH timing. -t_id represents the index of the first slot of the RACH timing in the system frame. -f_id represents the index of the RACH timing in the frequency domain, and -ul_carrier_id indicates the UL carrier type for receiving the RA preamble.

15. The BS according to claim 11, wherein, The SIB further transmits an indicator, which indicates whether the UE is allowed to access the cell when it is a RedCap UE.

16. A method used by a base station (BS) in a 3GPP-based wireless communication system, the method comprising: Sending a System Information Block (SIB) that includes information for cell access, the information being associated with at least the following: - The configuration of the first random access channel (RACH) associated with the first uplink bandwidth portion (UL BWP) for a normal UE, and - A second UL BWP for reducing the capability (RedCap) of a UE; as well as Receive random access (RA) preamble via one of the first UL BWP and the second UL BWP. Wherein, if the second RACH configuration for the second UL BWP is broadcast, the second RACH configuration is used for RA preamble reception in the second UL BWP, and If the second RACH configuration used for the second UL BWP is not broadcast, then the first RACH configuration used for the first UL BWP is used for RA preamble reception in the second UL BWP.

17. The method according to claim 16, wherein, In association with the RA preamble, a physical downlink control channel (PDCCH) for scheduling random access response (RAR) is transmitted.

18. The method according to claim 17, wherein, Regardless of where the RA preamble is received between the first UL BWP and the second UL BWP, the same equation is used to obtain the RA-Radio Network Temporary Identifier (RA-RNTI) associated with the PDCCH used for scheduling the RAR, and Specifically, based on the position of the RA preamble between the first UL BWP and the second UL BWP, the PDCCH for scheduling the RAR is sent via a corresponding initial DL BWP among a plurality of initial DL BWPs.

19. The method according to claim 18, wherein, The RA preamble is received at the RACH timing, and the equation includes: RA-RNTI = 1 + s_id + 14 × t_id + 14 × 80 × f_id + 14 × 80 × 8 × ul_carrier_id, where, -s_id represents the index of the first symbol of the RACH timing. -t_id represents the index of the first slot of the RACH timing in the system frame. -f_id represents the index of the RACH timing in the frequency domain, and -ul_carrier_id indicates the UL carrier type for receiving the RA preamble.

20. The method of claim 16, wherein, The SIB further transmits an indicator, which indicates whether the UE is allowed to access the cell when it is a RedCap UE.

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