Method, apparatus, and system for initial cell access in wireless communication system

Abstract

To provide a method, apparatus, and system for initial cell access in a wireless communication system.SOLUTION: User equipment 100 comprises: a communication module 120 that receives configuration information for configuring a first downlink bandwidth part (DL BWP) and a first uplink bandwidth part (UL BWP) to be used for an initial access procedure, receives an indicator indicating BWP access barring of first user equipment in a second UL BWP and a second DL BWP for legacy-type second user equipment, and performs, on the basis of the indicator, 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 that controls the reception of the configuration information, performance of the initial access procedure, and the reception of the indicator. A RedCap user equipment smoothly performs initial cell access, performs a random access procedure without a collision with existing legacy-type user equipment, and performs communication on the basis of various types of frequency hopping designs.SELECTED DRAWING: Figure 11

Description

[Technical field]

[0001] The present invention relates to wireless communication systems, and more particularly to an initial cell attachment method, apparatus and system in a wireless communication system. [Background technology]

[0002] Since the commercialization of 4G (4th generation) communication systems, efforts are being made to develop new 5G (5th generation) communication systems to meet the increasing demand for wireless data traffic. The 5G communication system is called a beyond 4G network communication system, a post LTE system, or a new radio (NR) system. In order to achieve a high data transmission rate, the 5G communication system includes a system operated using an ultra-high frequency (mmWave) band of 6 GHz or more, and is considered to be implemented in base stations and terminals including a communication system operated using a frequency band of 6 GHz or less in terms of ensuring coverage.

[0003] The 3GPP (3rd generation partnership project) NR system improves the spectrum efficiency of the network, allowing carriers to provide more data and voice services in a given bandwidth. Therefore, the 3GPP NR system is designed to meet the demand for high-speed data and media transmission in addition to high-capacity voice support. The advantages of the NR system are that it can have high throughput, low latency, FDD (frequency division duplex) and TDD (time division duplex) support on the same platform, improved end-user environment, and low operating costs due to a simple architecture.

[0004] For more efficient data processing, the dynamic TDD of the NR system can use a scheme of varying the number of OFDM (orthogonal frequency division multiplexing) symbols available for uplink and downlink according to the data traffic direction of a user in a cell. For example, when the downlink traffic of a cell is greater than the uplink traffic, the base station can allocate more downlink OFDM symbols to a slot (or subframe). Information about the slot configuration needs to be transmitted to the terminal.

[0005] In order to mitigate path loss and increase the transmission distance of radio waves in the ultra-high frequency band, beamforming, massive array multiple input / output (massive MIMO), full dimensional multiple input / output (FD-MIMO), array antenna, analog beam-forming, hybrid beamforming that combines analog beamforming and digital beamforming, and large scale antenna technologies are being discussed for 5G communication systems. In addition, to improve the system network, technologies being developed for the 5G communication system include advanced small cells, cloud radio access networks (cloud RAN), ultra-dense networks, device to device communication (D2D), vehicle to everything communication (V2X), wireless backhaul, non-terrestrial network communication (NTN), moving networks, cooperative communication, coordinated multi-points (CoMP), and interference cancellation.In addition, advanced coding modulation (ACM) methods such as FQAM (hybrid FSK and QAM modulation) and SWSC (sliding window superposition coding), as well as advanced access technologies such as FBMC (filter bank multi-carrier), NOMA (non-orthogonal multiple access) and SCMA (sparse code multiple access) are being developed for the 5G system.

[0006] Meanwhile, the Internet is evolving from a human-centered connected network where humans generate and consume information to an IoT (Internet of Things) network that exchanges and processes information between distributed components such as things. IoE (Internet of Everything) technology is also emerging, which combines big data processing technology using connections with cloud servers with IoT technology. To realize IoT, technological elements such as sensing technology, wired and wireless communication and network infrastructure, service interface technology, and security technology are required, and recently, technologies such as sensor networks for connecting things, communication between things (machine to machine, M2M), and machine type communication (MTC) are being researched. In the IoT environment, intelligent IT (internet technology) services can be provided that collect and analyze data generated from connected things to create new value in people's lives. IoT can be applied to fields such as smart homes, smart buildings, smart cities, smart cars or connected cars, smart grids, healthcare, smart home appliances, and advanced medical services through the fusion and integration of existing IT (information technology) technology and various industries.

[0007] Therefore, various attempts are being made to apply 5G communication systems to IoT networks. For example, technologies such as sensor networks, machine-to-machine (M2M) communication, and MTC (machine type communication) are being embodied by 5G communication technologies such as beamforming, MIMO, and array antennas. The application of cloud radio access network (cloud RAN) as the big data processing technology mentioned above can also be said to be an example of the fusion of 5G technology and IoT technology. In general, mobile communication systems have been developed to provide voice services while ensuring user activity.

[0008] The 3GPP study on "Self-assessment of IMT-2020 submissions" confirmed that NB IoT and LTE M can meet the IMT-2020 requirements for mMTC and be certified as 5G technologies. URLLC functionality was introduced in Rel-15 for both LTE and NR to support URLLC, and URLLC for NR systems was further enhanced in Rel-16 with enhanced URLLC (eURLLC) and the industrial IoT work item. Rel-16 also introduced Time-Sensitive Networking (TSN) and 5G integration support for the use of TSC.

[0009] One of the key goals of 5G is to enable connected industries. 5G connectivity will act as a catalyst for next-generation industrial innovation and digitalization, improving flexibility, increasing productivity and efficiency, reducing maintenance costs, and improving operational safety. Devices in this environment, such as pressure sensors, humidity sensors, thermometers, motion sensors, accelerometers, and actuators, will preferably be connected to the 5G radio access and core network. Large-scale industrial wireless sensor network use cases and requirements include URLLC services with very high requirements, as well as relatively inexpensive services with small device form factor requirements. They should also be able to operate wirelessly with batteries for several years. For example, such 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 [Problem to be solved by the invention]

[0010] SUMMARY OF THE PRESENT EMBODIMENTS The technical problem of the present invention is to provide an initial cell connection method and apparatus in a wireless communication system, particularly in a cellular wireless communication system.

[0011] Another technical object of the present invention is to provide a frequency hopping method and apparatus for uplink data transmission in a wireless communication system, particularly in a cellular wireless communication system. [Means for solving the problem]

[0012] According to one aspect of the present invention, there is provided a reduced capability first terminal (reduced capability UE) in a wireless communication system. The first terminal includes a communication module configured to receive configuration information for setting a first downlink bandwidth part (DL BWP) and a first uplink bandwidth part (Uplink BWP) used in an initial access procedure, receive an indicator indicating BWP access barring of the first terminal in a second UL BWP and a second DL BWP for a legacy type second terminal, and perform an initial access procedure in 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 for controlling the reception of the configuration information, the execution of the initial access procedure, and the reception of the indicator, wherein the first UL BWP and the second UL BWP are configured individually, the initial access procedure includes a random access procedure, and the first UL BWP includes a first resource for the random access procedure of the first terminal, and the first resource may be the same as a second resource for a random access procedure on the second UL BWP of the second terminal.

[0013] In one aspect, the communication module may be configured to obtain information regarding a basic control resource set (CORESET) from a second synchronization signal block (SSB) related to the second terminal.

[0014] In another aspect, the communications module may be configured to receive information regarding a CORESET for the first terminal defined separately from the CORESET for the second terminal using a system information block 1 (SIB1).

[0015] In yet another aspect, the communications module may be configured to receive SIB1 for the second terminal, the SIB1 including scheduling information related to system information for performing the initial access procedure of the first terminal.

[0016] In yet another aspect, the scheduling information may include information regarding a starting physical resource block (PRB) of the first DL BWP activated for execution of an initial access procedure of the first terminal.

[0017] In yet another aspect, the communications module may be configured to receive a SIB1 for the second terminal, the SIB1 including configuration information for an optional attachment procedure for an initial attachment of the first terminal.

[0018] In yet another aspect, the communications module may be configured to obtain information regarding a CORESET for the first terminal using a first SSB defined separately from a second SSB related to the second terminal.

[0019] In yet another aspect, the information about the basic CORESET is composed of 8 bits, and 4 bits of the information about the basic CORESET indicate information about the frequency domain in which the basic CORESET is set, and the remaining 4 bits indicate information about symbols for monitoring the basic CORESET.

[0020] In yet another aspect, the 8 bits constituting the information regarding the basic CORESET may be recognized as different information by the first terminal and the second terminal.

[0021] In yet another feature, the communications module can receive information from the base station indicating the first resource for the first terminal.

[0022] In yet another aspect, a portion of an optional connection preamble sequence available in a cell provided by the base station may be used for the first terminal, and a remaining portion may be used for the second terminal.

[0023] In yet another aspect, the communication module can obtain information regarding a CORESET for the first terminal based on information regarding the basic CORESET.

[0024] In yet another aspect, a first PDCCH candidate for the first terminal within the basic CORESET may be defined separately from a second PDCCH candidate for the second terminal, and the communications module may be configured to monitor the first PDCCH candidate within the basic CORESET.

[0025] According to another aspect of the present invention, there is provided a method for operating a reduced capability UE in a wireless communication system. The method includes receiving configuration information for configuring a first downlink bandwidth part (DL BWP) and a first uplink bandwidth part (Uplink BWP) used in an initial access procedure, receiving an indicator indicating BWP access barring of the first UE in a second UL BWP and a second DL BWP for a legacy type second UE, and performing an initial access procedure in 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, the first UL BWP and the second UL BWP are individually configured, 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 may be the same as a second resource for a random access procedure on the second UL BWP of the second UE.

[0026] In one aspect, the method may further include obtaining information regarding a basic control resource set (CORESET) from a second synchronization signal block (SSB) related to the second terminal.

[0027] In another aspect, the method may further include receiving information regarding a CORESET for the first terminal, the CORESET being defined separately from the CORESET for the second terminal, using a system information block 1 (SIB1).

[0028] In yet another aspect, the method may further include receiving SIB1 for the second terminal, the SIB1 including scheduling information related to system information for performing the initial access procedure of the first terminal.

[0029] In yet another aspect, the scheduling information may include information regarding a starting physical resource block (PRB) of the first DL BWP activated for execution of an initial access procedure of the first terminal.

[0030] In yet another aspect, the method may further include receiving an SIB1 for the second terminal, the SIB1 including configuration information for an optional connection procedure for an initial connection of the first terminal.

[0031] In yet another aspect, information regarding a CORESET for the first terminal can be obtained from a first SSB defined separately from a second SSB related to the second terminal. Effect of the Invention

[0032] According to an embodiment of the present invention, a RedCap terminal can smoothly perform initial cell connection, can perform optional connection procedures without collision with existing legacy type terminals, and can communicate based on various frequency hopping designs.

[0033] The effects obtained from the present invention are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those having ordinary skill in the art to which the present invention pertains from the following description. [Brief description of the drawings]

[0034] [Figure 1] FIG. 2 is a diagram illustrating an example of a radio frame structure used in a wireless communication system. [Diagram 2] FIG. 1 is a diagram illustrating an example of a downlink (DL) / uplink (UL) slot structure in a wireless communication system. [Diagram 3] FIG. 1 is a diagram illustrating a physical channel used in a 3GPP system (e.g., NR) and a general signal transmission method using the physical channel. [Figure 4a] A diagram showing SS / PBCH blocks for initial cell access in a 3GPP NR system. [Figure 4b] A diagram showing SS / PBCH blocks for initial cell access in a 3GPP NR system. [Figure 5a] A diagram showing a procedure for control information and control channel transmission in a 3GPP NR system. [Figure 5b] A diagram showing a procedure for control information and control channel transmission in a 3GPP NR system. [Figure 6] A diagram showing a CORESET in which a PDCCH is transmitted in a 3GPP NR system. [Figure 7] A diagram showing a method for setting a PDCCH search space in a 3GPP NR system. [Figure 8] FIG. 8 is a conceptual diagram illustrating carrier aggregation. [Figure 9]FIG. 2 is a diagram for explaining terminal carrier communication and multi-carrier communication. [Figure 10] A diagram showing an example in which a cross-carrier scheduling technique is applied. [Figure 11] 2 is a block diagram showing the configuration of a terminal and a base station according to an embodiment of the present invention. [Figure 12] FIG. 1 illustrates an example of an initial connection method. [Figure 13] 1 is a diagram showing an initial cell connection method according to one embodiment of the present invention. [Figure 14] A diagram showing an initial cell connection method and PRACH resource configuration according to one embodiment of the present invention. [Figure 15] A diagram showing an initial cell connection method and PRACH resource configuration according to another embodiment of the present invention. [Figure 16] A diagram showing an initial cell connection method and PRACH resource configuration according to yet another embodiment of the present invention. [Figure 17] FIG. 13 is a diagram illustrating an initial cell connection method according to another embodiment of the present invention. [Figure 18] FIG. 13 is a diagram illustrating an initial cell connection method according to yet another embodiment of the present invention. [Figure 19] FIG. 13 is a diagram illustrating an initial cell connection method according to yet another embodiment of the present invention. [Figure 20] FIG. 13 is a diagram illustrating an initial cell connection method according to yet another embodiment of the present invention. [Figure 21] FIG. 13 is a diagram illustrating an initial cell connection method according to yet another embodiment of the present invention. [Figure 22] A diagram showing PRACH resource configuration according to yet another embodiment of the present invention. [Figure 23] A diagram showing scheduling of a physical uplink shared channel in the time domain. [Figure 24] A diagram showing scheduling of a physical uplink shared channel in the frequency domain. [Diagram 25] A diagram showing repeated transmission of a physical uplink shared channel according to an example. [Figure 26]A diagram showing scheduling of the physical uplink control channel. [Figure 27] A diagram showing repeated transmission of a physical uplink control channel. [Figure 28] FIG. 1 illustrates frequency hopping. [Figure 29] FIG. 1 illustrates wideband frequency hopping. [Diagram 30] FIG. 2 illustrates wideband frequency hopping according to one embodiment of the present invention. [Diagram 31] FIG. 11 illustrates wideband frequency hopping according to another embodiment of the present invention. [Diagram 32] FIG. 13 is a diagram illustrating wideband frequency hopping according to yet another embodiment of the present invention. [Diagram 33] FIG. 2 illustrates wideband frequency hopping according to one embodiment of the present invention. [Diagram 34] FIG. 13 is a diagram illustrating a PUSCH repetition type B according to an example. [Diagram 35] FIG. 13 illustrates a gap symbol in a Type-B PUSCH repetition being placed in a previous nominal repetition according to one embodiment of the present invention. [Diagram 36] FIG. 13 is a diagram showing a type-B PUSCH repetition in which a gap symbol is placed in a subsequent nominal repetition according to one embodiment of the present invention. [Figure 37] 13 is a diagram showing gap symbols being distributed in a Type B PUSCH repetition according to one embodiment of the present invention; FIG. [Figure 38] FIG. 13 is a diagram illustrating a type-B PUSCH repetition in which gap symbols are placed in a nominal repetition having a large number in accordance with one embodiment of the present invention. [Figure 39] FIG. 13 is a diagram showing a type-B PUSCH repetition in which gap symbols are placed in a nominal repetition having a small number in accordance with one embodiment of the present invention. [Diagram 40] 13 is a diagram illustrating gap symbols arranged to prevent orphan symbols from occurring in a Type B PUSCH repetition according to one embodiment of the present invention. FIG. [Diagram 41]13 is a diagram illustrating a type-B PUSCH repetition in which a gap symbol is added after a nominal repetition in accordance with one embodiment of the present invention. [Diagram 42] 11 is a diagram illustrating gap symbols taking into account invalid UL symbols and orphan symbols in Type-B PUSCH repetition according to one embodiment of the present invention. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0035] The terms used in this specification are selected as common terms currently widely used as much as possible in consideration of the functions in the present invention, but this may vary depending on the intentions, customs, or the emergence of new technologies of the engineers in this field. In addition, in certain cases, the applicant may arbitrarily select some terms, and in this case, the meaning will be described in the description of the relevant invention. Therefore, it is clear that the terms used in this specification should be interpreted based on the substantial meaning of the terms and the contents of the entire specification, rather than simply the names of the terms.

[0036] Throughout the specification, when a certain component is "connected" to another component, this includes not only "direct connection" but also "electrical connection" through other components in between. Furthermore, when a certain component is "included" in a certain component, this does not mean excluding other components, but further includes other components, unless otherwise specified to the contrary. In addition, limitations such as "more than" or "less than" based on a specific threshold may be appropriately replaced with "more than" or "less than", respectively, depending on the embodiment.

[0037] The following technologies are 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), single carrier frequency division multiple access (SC-FDMA), etc. CDMA is implemented in radio technologies such as Universal Terrestrial Radio Access (UTRA) and CDMA2000. TDMA is implemented in radio technologies such as Global System for Mobile communications (GSM), General Packet Radio Service (GPRS), and Enhanced Data Rates for GSM Evolution (EDGE). OFDMA is implemented in radio technologies such as IEEE802.11 (Wi-Fi), IEEE802.16 (WiMAX), IEEE802-20, Evolved UTRA (E-UTRA), etc. UTRA is part of the Universal Mobile Telecommunication System (UMTS). 3GPP LTE (Long term evolution) is a part of E-UMTS (Evolved UMTS) that uses E-UTRA, and LTE-A (Advanced) is an evolved version of 3GPP LTE. 3GPP NR is a system designed separately from LTE / LTE-A, and is a system for supporting eMBB (enhanced Mobile BroadBand), URLLC (Ultra-Reliable and Low Latency Communication), and mMTC (massive Machine Type Communication) services, which are requirements of IMT-2020. For clarity of explanation, the following description will focus on 3GPP NR, but the technical idea of ​​the present invention is not limited thereto.

[0038] Unless otherwise specified in this specification, the base station may include a next generation node B (gNB) defined in 3GPP NR. Also, unless otherwise specified, the terminal may include a user equipment (UE).

[0039] FIG. 1 is a diagram showing an example of a radio frame structure used in a wireless communication system. Referring to FIG. 1, a radio frame (or radio frame) used in a 3GPP NR system has a length of 10 ms (ΔfmaxNf / 100)*Tc). The radio frame is made up of 10 equally sized subframes (SF). Here, Δfmax=480*103 Hz, Nf=4096, Tc=1 / (Δfref*Nf,ref), Δfref=15*103 Hz, and Nf,ref=2048. The 10 subframes in one frame are numbered from 0 to 9. Each subframe has a length of 1 ms and is made up of one or more slots depending on the subcarrier spacing. More specifically, the subcarrier spacing that can be used in a 3GPP NR system is 15*2μkHz. μ is a subcarrier spacing configuration factor, and has a value of μ=0 to 4. That is, 15 kHz, 30 kHz, 60 kHz, 120 kHz, or 240 kHz is used as the subcarrier spacing. A 1 ms long subframe consists of 2μ slots. In this case, the length of each slot is 2-μms. The 2μ slots in one subframe are numbered from 0 to 2μ-1. Also, the slots in one radio frame are numbered from 0 to 10*2μ-1. Time resources are divided by at least one of the radio frame number (also called radio frame index), subframe number (also called subframe index), and slot number (or slot index).

[0040] FIG. 2 is a diagram illustrating an example of a downlink (DL) / uplink (UL) slot structure in a wireless communication system. In particular, FIG. 2 illustrates a resource grid structure of a 3GPP NR system. There is one resource grid per antenna port. Referring to FIG. 2, a slot includes a plurality of OFDM symbols in the time domain and a plurality of resource blocks (RBs) in the frequency domain. An OFDM symbol also means one symbol period. Unless otherwise specified, an OFDM symbol is simply referred to as a symbol. Hereinafter, in this specification, a symbol includes an OFDM symbol, an SC-FDMA symbol, a DFTs-OFDM symbol, and the like. Referring to FIG. 2, a signal transmitted from each slot is represented by a resource grid consisting of Nsize, μgrid, x*NRBSC subcarriers, and Nslotsymb OFDM symbols. Here, x=DL for the downlink resource grid, and x=UL for the uplink resource grid. Nsize, μgrid, and x indicate the number of resource blocks (RBs) according to the subcarrier spacing factor μ (x is DL or UL), and Nslotsymb indicates the number of OFDM symbols in a slot. NRBSC is the number of subcarriers that make up one RB, and NRBSC=12. OFDM symbols are called cyclic prefix OFDM (CP-OFDM) symbols or discrete Fourier transform spread OFDM (DFT-S-OFDM) symbols depending on the multiple access method.

[0041] The number of OFDM symbols included in one slot may vary depending on the length of a cyclic prefix (CP). For example, a normal CP includes 14 OFDM symbols in one slot, whereas an extended CP includes 12 OFDM symbols in one slot. In a specific embodiment, the extended CP is used only at a subcarrier interval of 60 kHz. For convenience of explanation, FIG. 2 illustrates a case where one slot includes 14 OFDM symbols, but the embodiment of the present invention is also applicable to slots having other numbers of OFDM symbols in the same manner. Referring to FIG. 2, each OFDM symbol includes Nsize, μgrid, and x*NRBSC subcarriers in the frequency domain. The types of subcarriers are classified into data subcarriers for transmitting data, reference signal subcarriers for transmitting a reference signal, and guard bands. The carrier frequency is also called a center frequency (fc).

[0042] One RB is defined by NRBSC (e.g., 12) consecutive subcarriers in the frequency domain. Incidentally, a resource consisting of one OFDM symbol and one subcarrier is called a resource element (RE) or tone. Thus, one RB consists of Nslotsymb*NRBSC resource elements. Each resource element in the resource grid is uniquely defined by an index pair (k, l) in one slot. k is an index given from 0 to Nsize,μgrid,x*NRBSC-1 in the frequency domain, and l is an index given from 0 to Nslotsymb-1 in the time domain.

[0043] In order for a terminal to receive a signal from a base station or transmit a base station signal, the time / frequency synchronization of the terminal should be aligned with the time / frequency synchronization of the base station, because if the base station and the terminal are not synchronized, the terminal cannot determine the time and frequency parameters required to demodulate DL signals and transmit UL signals at the correct time.

[0044] Each symbol of a radio frame operating in time division duplex (TDD) or unpaired spectrum consists of at least one of downlink symbol (DL symbol), uplink symbol (UL symbol) or flexible symbol. A radio frame operating in frequency division duplex (FDD) or paired spectrum with a downlink carrier consists of downlink symbols or flexible symbols, and a radio frame operating with an uplink carrier consists of uplink symbols or flexible symbols. A downlink symbol allows downlink transmission but not uplink transmission, and an uplink symbol allows uplink transmission but not downlink transmission. Whether a flexible symbol is used in the downlink or uplink is determined depending on the signal.

[0045] Information on the type of each symbol, i.e., information indicating any one of the downlink symbol, the uplink symbol, and the flexible symbol, is composed of a cell-specific (cell-specific or common) RRC signal. In addition, the information on the type of each symbol is additionally composed of a specific terminal (UE-specific or dedicated) RRC signal. The base station uses the cell-specific RRC signal to inform i) the period of the cell-specific slot configuration, ii) the number of slots having only downlink symbols from the beginning of the period of the cell-specific slot configuration, iii) the number of downlink symbols from the first symbol in the slot immediately after the slot having only downlink symbols, iv) the number of slots having only uplink symbols from the end of the period of the cell-specific slot configuration, and v) the number of uplink symbols from the last symbol in the slot immediately before the slot having only uplink symbols. Here, a symbol that is not configured as either an uplink symbol or a downlink symbol is a flexible symbol.

[0046] If the information regarding the symbol type consists of the UE-specific RRC signal, the base station signals, via the cell-specific RRC signal, whether the flexible symbol is a downlink symbol or an uplink symbol. At this time, the UE-specific RRC signal cannot change the downlink symbol or uplink symbol that consists of the cell-specific RRC signal to another symbol type. The UE-specific RRC signal signals, for each slot, the number of downlink symbols among the Nslotsymb symbols of the slot and the number of uplink symbols among the Nslotsymb symbols of the slot. At this time, the downlink symbols of the slot are continuously configured from the first symbol to the i-th symbol of the slot. Also, the uplink symbols of the slot are continuously configured from the j-th symbol to the last symbol of the slot (where i < j). In a slot, a symbol that is not configured as either an uplink symbol or a downlink symbol is a flexible symbol.

[0047] The type of symbol configured by the RRC signal as described above can be called a semi-static DL / UL configuration. In the semi-static DL / UL configuration configured by the RRC signal previously, the flexible symbol may be indicated as a downlink symbol, an uplink symbol, or a flexible symbol by the dynamic SFI (slot format information) transmitted on the physical downlink control channel (PDCCH). At this time, the downlink symbol or uplink symbol configured by the RRC signal is not changed to another symbol type. Table 1 exemplifies the dynamic SFI that the base station can indicate to the UE.

[0048]

Table 1

[0049] In Table 1, D represents a downlink symbol, U represents an uplink symbol, and X represents a flexible symbol. As shown in Table 1, up to two DL / UL switchings may be allowed in one slot.

[0050] FIG. 3 is a diagram for explaining physical channels used in a 3GPP system (e.g., NR) and a general signal transmission method using the physical channels. When a terminal is turned on or enters a new cell, the terminal performs an initial cell search operation S101. More specifically, the terminal synchronizes with a base station in the initial cell search. To this end, the terminal receives a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) from the base station to synchronize with the base station and obtain information such as a cell ID. Next, the terminal receives a physical broadcast channel from the base station to obtain broadcast information within the cell.

[0051] After completing the initial cell search, the terminal receives a physical downlink shared channel (PDSCH) via a physical downlink control channel (PDCCH) and information carried on the PDCCH, thereby acquiring more detailed system information than the system information acquired through the initial cell search (S102).

[0052] When a terminal first connects to a base station or when there are no radio resources for signal transmission, the terminal can perform a random access procedure with respect to the base station (steps S103 to S106). First, the terminal transmits a preamble on a physical random access channel (PRACH) (S103) and can receive a response message for the preamble from the base station on a PDCCH and a corresponding PDSCH (S104). If the terminal receives a valid random access response message, the terminal transmits data including its own identifier, etc. to the base station on a physical uplink shared channel (PUSCH) indicated by an uplink grant transmitted from the base station on the PDCCH (S105). Next, the terminal waits to receive a PDCCH as an instruction from the base station to resolve collisions. If the terminal successfully receives a PDCCH with its own identifier (S106), the random access procedure ends.

[0053] After the above-mentioned procedure, the terminal receives PDCCH / PDSCH S107 and transmits physical uplink shared channel (PUSCH) / physical uplink control channel (PUCCH) S108 as a general uplink / downlink signal transmission procedure. In particular, the terminal receives downlink control information (DCI) via the PDCCH. The DCI includes control information such as resource allocation information for the terminal. The format of the DCI may differ depending on the purpose of use. The uplink control information (UCI) transmitted by the terminal to the base station via the uplink includes downlink / uplink ACK / NACK signals, a channel quality indicator (CQI), a precoding matrix index (PMI), a rank indicator (RI), and the like. Here, the CQI, PMI, and RI are included in channel state information (CSI). In the case of a 3GPP NR system, the terminal transmits control information such as the above-mentioned HARQ-ACK and CSI via the PUSCH and / or PUCCH.

[0054] 4a and 4b are diagrams showing a synchronization signal (SS) / physical broadcast channel (PBCH) block for initial cell access in a 3GPP NR system. When a terminal is powered on or attempts to access a new cell, the terminal acquires time and frequency synchronization with the cell and performs an initial cell search process. In the cell search process, the terminal obtains a physical cell identity N cell ID To this end, the terminal receives synchronization signals, such as a primary synchronization signal (PSS) and a secondary synchronization signal (SSS), from the base station to synchronize with the base station. At this time, the terminal obtains information such as a cell identity (ID).

[0055] The synchronization signal (SS) will be described in more detail with reference to FIG. 4a and FIG. 4b. The synchronization signal is divided into PSS and SSS. The PSS is used to obtain time domain synchronization and / or frequency domain synchronization such as OFDM symbol synchronization and slot synchronization. The SSS is used to obtain frame synchronization and cell group ID. With reference to FIG. 4a and Table 2, the SS / PBCH block consists of 20 consecutive RBs (=240 subcarriers) on the frequency axis and 4 consecutive OFDM symbols on the time axis. In this case, in the SS / PBCH block, the PSS is transmitted in the first OFDM symbol and the SSS is transmitted in the third OFDM symbol via the 56th to 18th subcarriers. Here, the lowest subcarrier index of the SS / PBCH block is numbered from 0. In the first OFDM symbol in which the PSS is transmitted, the base station does not transmit signals via the remaining subcarriers, i.e., the 0th to 55th and 183rd to 239th subcarriers. In addition, in the third OFDM symbol in which the SSS is transmitted, the base station does not transmit signals via subcarriers 48 to 55 and 183 to 19. The base station transmits a physical broadcast channel (PBCH) via the remaining REs in the SS / PBCH block excluding the above-mentioned signals.

[0056] [Table 2]

[0057] The SS is grouped into 336 physical layer cell ID groups, each of which includes three unique identifiers, so that a total of 1008 unique physical layer cell IDs are obtained through a combination of three PSSs and SSSs, more specifically, each physical layer cell ID is part of only one physical layer cell ID group. Thus, a physical layer cell ID NcellID=3N(1)ID+N(2)ID is uniquely defined by an index N(1)ID ranging from 0 to 335 indicating a physical layer cell ID group and an index N(2)ID ranging from 0 to 2 indicating a physical layer identifier in the physical layer cell ID group. The UE detects the PSS and identifies one of the three unique physical layer identifiers. The UE also detects the SSS and identifies one of the 336 physical layer cell IDs associated with the physical layer identifier. In this case, the sequence dPSS(n) of the PSS is expressed as the following Equation 1.

[0058]

number

[0059]

number

[0060]

number

[0061] Where:

[0062]

number

[0063] and

[0064]

number

[0065] It is given that:

[0066] Also, the SSS sequence dSSS(n) is as follows:

[0067]

number

[0068]

number

[0069]

number

[0070]

number

[0071] Where:

[0072]

number

[0073]

number

[0074]

number

[0075]

number

[0076] It is given that:

[0077] A radio frame with a length of 10 ms is divided into two half-frames with a length of 5 ms. The slots in which the SS / PBCH block is transmitted in each half-frame are described with reference to FIG. 4b. The slots in which the SS / PBCH block is transmitted are any one 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*nth symbol. In this case, n=0, 1 for carrier frequencies below 3 GHz. Also, n=0, 1, 2, 3 for carrier frequencies above 3 GHz and below 6 GHz. In case B, the subcarrier spacing is 30 kHz, and the start time of the SS / PBCH block is the {4, 8, 16, 20}+28*nth symbol. In this case, n=0 for carrier frequencies below 3 GHz. Also, n=0, 1 for carrier frequencies above 3 GHz and below 6 GHz. In case C, the subcarrier spacing is 30 kHz and the start of the SS / PBCH block is {2, 8}+14*n symbols, where n=0, 1 for carrier frequencies below 3 GHz. Also, n=0, 1, 2, 3 for carrier frequencies above 3 GHz and below 6 GHz. In case D, the subcarrier spacing is 120 kHz and the start of the SS / PBCH block is {4, 8, 16, 20}+28*n symbols, where n=0, 1, 2, 3, 5, 6, 7, 8, 10, 11, 12, 13, 15, 16, 17, 18 for carrier frequencies above 6 GHz. In case E, the subcarrier spacing is 240 kHz and the start of the SS / PBCH block is {8, 12, 16, 20, 32, 36, 40, 44}+56*n symbols. In this case, n=0, 1, 2, 3, 5, 6, 7, 8 for carrier frequencies of 6 GHz or higher.

[0078] 5a and 5b are diagrams illustrating a procedure for transmitting control information and a control channel in a 3GPP NR system. Referring to FIG. 5a, a base station adds a cyclic redundancy check (CRC) masked (e.g., XORed) with a radio network temporary identifier (RNTI) to control information (e.g., DCI) S202. The base station scrambles the CRC with an RNTI value determined according to the purpose / target of each control information. The common RNTI used by one or more terminals includes at least one of a system information RNTI (SI-RNTI), a paging RNTI (P-RNTI), a random access RNTI (RA-RNTI), and a transmit power control RNTI (TPC-RNTI). Also, the UE specific RNTI includes at least one of a cell temporary RNTI (C-RNTI), a CS-RNTI, or an MCS-C-RNTI. Next, the base station performs channel encoding (e.g., polar coding) S204, and then performs rate-matching according to the amount of resource(s) used for PDCCH transmission S206. Next, the base station multiplexes DCI(s) based on a control channel element (CCE)-based PDCCH structure S208.

[0079] In addition, the base station applies additional processes S210 such as scrambling, modulation (e.g., QPSK), and interleaving to the multiplexed DCI, and then maps it to resources to be transmitted. A CCE is a basic resource unit for a PDCCH, and one CCE consists of a plurality of (e.g., 6) resource element groups (REGs). One REG consists of a plurality of (e.g., 12) REs. The number of CCEs used for one PDCCH is defined as an aggregation level. In the 3GPP NR system, aggregation levels of 1, 2, 4, 8, or 16 are used. Figure 5b is a diagram related to CCE aggregation levels and PDCCH multiplexing, and shows the types of CCE aggregation levels used for one PDCCH and the CCEs transmitted in the control region according to the respective aggregation levels.

[0080] FIG. 6 is a diagram showing a control resource set (CORESET) in which a physical downlink control channel (PDCCH) is transmitted in a 3GPP NR system. The CORESET is a time-frequency resource in which a PDCCH, which is a control signal for a terminal, is transmitted. A search space, which will be described later, is mapped to one CORESET. Thus, the terminal does not monitor all frequency bands to receive the PDCCH, but monitors a time-frequency region designated as the CORESET and decodes the PDCCH mapped to the CORESET. The base station configures one or more CORESETs for each cell in the terminal. The CORESET is made up of up to three consecutive symbols on the time axis. The CORESET is made up of six units of consecutive PRBs on the frequency axis. In the embodiment of FIG. 5, the CORESET#1 is made up of consecutive PRBs, and the CORESET#2 and CORESET#3 are made up of non-consecutive PRBs. The CORESET may be located at any symbol in a slot. For example, in the embodiment of FIG. 5, CORESET#1 begins at the first symbol of the slot, CORESET#2 begins at the fifth symbol of the slot, and CORESET#9 begins at the ninth symbol of the slot.

[0081] FIG. 7 is a diagram illustrating a method for setting a PDCCH search space in a 3GPP NR system. In order to transmit a PDCCH to a terminal, at least one search space exists in each CORESET. In an embodiment of the present invention, the search space is a set of all time-frequency resources (hereinafter, PDCCH candidates) in which the PDCCH of the terminal is transmitted. The search space includes a common search space that 3GPP NR terminals should commonly search, and a terminal-specific or UE-specific search space that a specific terminal should search. In the common search space, a PDCCH that is set to be commonly searched by all terminals in a cell belonging to the same base station is monitored. In addition, the terminal-specific search space is set for each terminal so that the PDCCH allocated to each terminal is monitored at a position of the search space that differs from one another according to the terminal. In the case of the terminal-specific search space, the search spaces between terminals may be partially overlapped due to the limited control region to which the PDCCH is allocated. Monitoring the PDCCH includes blind decoding the PDCCH candidates in the search space. If blind decoding is successful, it is expressed as the PDCCH being (successfully) detected / received, and if blind decoding is unsuccessful, it is expressed as the PDCCH being undetected / not received or not successfully detected / received.

[0082] For convenience of explanation, a PDCCH scrambled with a group common (GC) RNTI already known by one or more terminals to transmit downlink control information to one or more terminals is referred to as a group common (GC) PDCCH or a common PDCCH. Also, a PDCCH scrambled with a terminal specific RNTI already known by a specific terminal to transmit uplink scheduling information or downlink scheduling information to one specific terminal is referred to as a terminal specific PDCCH. The common PDCCH is included in a common search space, and the terminal specific PDCCH is included in a common search space or a terminal specific PDCCH.

[0083] The base station notifies each terminal or terminal group of information on resource allocation of the transmission channels PCH (paging channel) and DL-SCH (downlink-shared channel) (i.e., DL Grant) or information on UL-SCH resource allocation and hybrid automatic repeat request (HARQ) (i.e., UL Grant) via the PDCCH. The base station transmits a PCH transport block and a DL-SCH transport block via the PDSCH. The base station transmits data excluding specific control information or specific service data via the PDSCH. Also, the terminal receives data excluding specific control information or specific service data via the PDSCH.

[0084] The base station transmits information on which terminal (one or more terminals) the PDSCH data is transmitted to and how the terminal should receive and decode the PDSCH data by including it in the PDCCH. For example, assume that the DCI transmitted through a specific PDCCH is CRC masked with RNTI "A", the DCI indicates that the PDSCH is allocated to radio resource "B" (e.g., frequency position) and indicates transmission format information "C" (e.g., transmission block size, modulation method, coding information, etc.). The terminal monitors the PDCCH using its own RNTI information. In this case, if there is a terminal that blind decodes the PDCCH using RNTI "A", the terminal receives the PDCCH and receives the PDSCH indicated by "B" and "C" through the received PDCCH information.

[0085] Table 3 shows one embodiment of a PUCCH used in a wireless communication system.

[0086] [Table 3]

[0087] The PUCCH is used to transmit the following uplink control information (UCI):

[0088] - SR (Scheduling Request): Information used to request uplink UL-SCH resources.

[0089] -HARQ-ACK: A response to a PDCCH (indicating DL SPS release) and / or a response to an uplink transport block (TB) on a PDSCH. HARQ-ACK indicates receipt of information transmitted via a PDCCH or PDSCH. HARQ-ACK responses include positive ACK (simply, ACK), negative ACK (hereinafter, NACK), DTX (Discontinuous Transmission), or NACK / DTX. Here, the term HARQ-ACK is used interchangeably with HARQ-ACK / NACK and ACK / NACK. In general, ACK is represented by a bit value of 1 and NACK is represented by a bit value of 0.

[0090] -CSI: Feedback information for a downlink channel. It is generated by a terminal based on a CSI-RS (Reference Signal) transmitted by a base station. MIMO (multiple input multiple output)-related feedback information includes RI and PMI. CSI is divided into CSI part 1 and CSI part 2 according to the information indicated by CSI.

[0091] In the 3GPP NR system, five PUCCH formats are used to support various service scenarios and various channel environments and frame structures.

[0092] PUCCH format 0 is a format that transmits 1-bit or 2-bit HARQ-ACK information or SR. PUCCH format 0 is transmitted through one or two OFDM symbols on the time axis and one RB on the frequency axis. If PUCCH format 0 is transmitted with two OFDM symbols, the same sequence is transmitted with different RBs for the two symbols. Through this, the terminal obtains frequency diversity gain. More specifically, the terminal determines a cyclic shift value mcs according to the Mbit bit UCI (Mbit=1 or 2), and transmits a sequence obtained by cyclically shifting a base sequence of length 12 by the determined value mcs, by mapping the sequence to 12 REs of one OFDM symbol and one PRB. If the number of cyclic shifts available to the terminal is 12 and Mbit=1, 1-bit UCI 0 and 1 are represented by sequences corresponding to two cyclic shifts with a cyclic shift value difference of 6. Also, if Mbit=2, then 2-bit UCI 00, 01, 11, 10 is represented by a sequence corresponding to four cyclic shifts with a difference between the cyclic shift values ​​being three.

[0093] PUCCH format 1 transmits 1-bit or 2-bit HARQ-ACK information or SR. PUCCH format 1 is transmitted through continuous OFDM symbols on the time axis and one PRB on the frequency axis. Here, the number of OFDM symbols occupied by PUCCH format 1 is one of 4 to 14. More specifically, UCI with Mbit=1 is modulated by BPSK. The terminal modulates UCI with Mbit=2 by quadrature phase shift keying (QPSK). A signal is obtained by multiplying the modulated complex valued symbol d(0) by a sequence of length 12. In this case, the sequence may be a base sequence used for PUCCH format 0. The terminal transmits the obtained signal by spreading it by a time-axis orthogonal cover code (OCC) on the even-numbered OFDM symbols to which PUCCH format 1 is assigned. In PUCCH format 1, the maximum number of different terminals to be multiplexed in the same RB can be determined according to the length of the OCC used. In odd-numbered OFDM symbols of PUCCH format 1, a demodulation reference signal (DMRS) is spread by OCC and mapped.

[0094] PUCCH format 2 transmits UCI exceeding 2 bits. PUCCH format 2 is transmitted through one or two OFDM symbols on the time axis and one or more RBs on the frequency axis. If PUCCH format 2 is transmitted through two OFDM symbols, the same sequence is transmitted through two OFDM symbols in different RBs. In this way, the terminal obtains frequency diversity gain. More specifically, Mbit UCI (Mbit>2) is bit-level scrambled, QPSK modulated, and mapped to RBs of one or two OFDM symbol(s). Here, the number of RBs is one of 1 to 16.

[0095] PUCCH format 3 or PUCCH format 4 transmits UCI exceeding 2 bits. PUCCH format 3 or PUCCH format 4 is transmitted through continuous 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 is one of 4 to 14. In particular, the terminal modulates Mbit UCI (Mbit>2) with π / 2-BPSK (Binary Phase Shift Keying) or QPSK to generate complex symbols d(0) to d(Msymb-1). Here, Msymb=Mbit when π / 2-BPSK is used, and Msymb=Mbit / 2 when QPSK is used. The terminal does not apply block-wise spreading to PUCCH format 3. However, the terminal may apply block-wise spreading to one RB (i.e., 12 subcarriers) using PreDFT-OCC of length -12 so that PUCCH format 4 has a multiplexing capacity of 2 or 4. The terminal transmit precoding (or DFT-precoding) the spread signal, maps it to each RE, and transmits the spread signal.

[0096] In this case, the number of RBs occupied by PUCCH format 2, PUCCH format 3, or PUCCH format 4 is determined according to the length of UCI transmitted by the terminal and the maximum code rate. If the terminal uses PUCCH format 2, the terminal transmits both HARQ-ACK information and CSI information via PUCCH. If the number of RBs that the terminal can transmit is greater than the maximum number of RBs that PUCCH format 2, PUCCH format 3, or PUCCH format 4 can use, the terminal does not transmit some UCI information according to the priority of the UCI information and transmits only the remaining UCI information.

[0097] PUCCH format 1, PUCCH format 3, or PUCCH format 4 is configured via RRC signaling to indicate frequency hopping within a slot. When frequency hopping is configured, the index of the RB to be frequency hopped is configured via RRC signaling. If PUCCH format 1, PUCCH format 3, or PUCCH format 4 is transmitted across N OFDM symbols in the time axis, the first hop has floor(N / 2) OFDM symbols and the second hop has ceil(N / 2) OFDM symbols.

[0098] PUCCH format 1, PUCCH format 3, or PUCCH format 4 is configured to be repeatedly transmitted in multiple slots. In this case, the number K of slots in which the PUCCH is repeatedly transmitted is configured by an RRC signal. The repeatedly transmitted PUCCH should start from the same OFDM symbol position in each slot and have the same length. If the RRC signal indicates that any one of the OFDM symbols in a slot in which the UE should transmit the PUCCH is a DL symbol, the UE does not transmit the PUCCH from the slot, but postpones it to the next slot for transmission.

[0099] Meanwhile, in a 3GPP NR system, a terminal transmits and receives using a bandwidth smaller than or equal to the bandwidth of a carrier (or cell). To this end, the terminal is configured with a BWP (bandwidth part) consisting of a continuous bandwidth that is a part of the carrier bandwidth. A terminal operating according to TDD or in an unpaired spectrum is configured with up to four DL / UL BWP pairs for one carrier (or cell). The terminal also activates one DL / UL BWP pair. A terminal operating according to FDD or in a paired spectrum is configured with up to four DL BWPs for a downlink carrier (or cell) and up to four UL BWPs for an uplink carrier (or cell). The terminal activates one DL BWP and one UL BWP for each carrier (or cell). The terminal may not receive or transmit from time-frequency resources other than the activated BWP. The activated BWP is called an active BWP.

[0100] The base station refers to an activated BWP among the BWPs configured for the terminal as a DCI. The BWP indicated by the DCI is activated, and the other configured BWP(s) is deactivated. In a carrier (or cell) operating in TDD, the base station includes a BPI (bandwidth part indicator) indicating the activated BWP in the DCI for scheduling the PDSCH or PUSCH to change the DL / UL BWP pair of the terminal. The terminal receives the DCI for scheduling the PDSCH or PUSCH and identifies the activated DL / UL BWP pair based on the BPI. In the case of a downlink carrier (or cell) operating in FDD, the base station includes a BPI indicating the activated BWP in the DCI for scheduling the PDSCH to change the DL BWP of the terminal. In the case of an uplink carrier (or cell) operating in FDD, the base station includes a BPI indicating the activated BWP in the DCI for scheduling the PDSCH to change the UL BWP of the terminal.

[0101] FIG. 8 is a conceptual diagram illustrating carrier aggregation.

[0102] Carrier aggregation refers to a method in which a terminal uses multiple frequency blocks or (logical) cells consisting of uplink resources (or component carriers) and / or downlink resources (or component carriers) in one large logical frequency band in order for a wireless communication system to use a wider frequency band. For convenience of explanation, the term "component carrier" will be used hereinafter.

[0103] Referring to FIG. 8, as an example of a 3GPP NR system, the entire system band includes up to 16 component carriers, and each component carrier has a bandwidth of up to 400 MHz. The component carrier includes one or more physically contiguous subcarriers. Although each component carrier is shown to have the same bandwidth in FIG. 8, this is merely an example, and each component carrier may have a different bandwidth. Also, although each component carrier is shown to be adjacent to each other on the frequency axis, the drawing is a logical concept, and each component carrier may be physically adjacent to each other or separated from each other.

[0104] A different center frequency is used in each component carrier. Also, a common center frequency is used in physically adjacent component carriers. In the embodiment of FIG. 8, if it is assumed that all component carriers are physically adjacent, center frequency A is used in all component carriers. Also, if it is assumed that each component carrier is not physically adjacent, center frequency A and center frequency B are used in each component carrier.

[0105] When the entire system band is expanded by carrier aggregation, the frequency band used for communication with each terminal is defined in component carrier units. Terminal A uses the entire system band of 100 MHz and communicates using all five component carriers. Terminals B1 to B5 use only a 20 MHz bandwidth and communicate using one component carrier. Terminals C1 and C2 use only a 40 MHz bandwidth and communicate using two component carriers each. The two component carriers may be logically / physically adjacent or not adjacent. The embodiment of FIG. 8 shows a case where terminal C1 uses two non-adjacent component carriers and terminal C2 uses two adjacent component carriers.

[0106] 9 is a diagram for explaining terminal carrier communication and multi-carrier communication. In particular, FIG. 9(a) shows a subframe structure of a single carrier, and FIG. 9(b) shows a subframe structure of a multi-carrier.

[0107] Referring to FIG. 9(a), a general wireless communication system transmits or receives data through one DL band and one corresponding UL band in the FDD mode. In another specific embodiment, in the TDD mode, the wireless communication system divides a wireless frame into an uplink time unit and a downlink time unit in the time domain, and transmits or receives data through the uplink / downlink time unit. Referring to FIG. 9(b), three 20 MHz component carriers (CCs) are aggregated in the UL and DL, respectively, to support a bandwidth of 60 MHz. The CCs are adjacent or non-adjacent to each other in the frequency domain. Although FIG. 9(b) illustrates a case in which the bandwidth of the UL CC and the bandwidth of the DL CC are the same and symmetrical for convenience, the bandwidth of each CC may be determined independently. Also, asymmetric carrier aggregation in which the number of UL CCs and the number of DL CCs are different is possible. The DL / UL CC allocated / configured to a specific terminal through RRC is called a serving DL / UL CC of the specific terminal.

[0108] The base station activates some or all of the serving CCs of the terminal, or deactivates some of the CCs to communicate with the terminal. The base station may change the CCs to be activated / deactivated, or may change the number of CCs to be activated / deactivated. When the base station allocates CCs available to the terminal in a cell-specific or terminal-specific manner, at least one of the CCs once allocated may not be deactivated unless the CC allocation for the terminal is completely reconfigured or the terminal is handed over. A CC that is not deactivated by the terminal is called a primary CC (PCC) or PCell (primary cell), and a CC that the base station can activate / deactivate freely is called a secondary CC (SCC) or SCell (secondary cell).

[0109] Meanwhile, 3GPP NR uses the concept of a cell to manage radio resources. A cell is defined as a combination of downlink and uplink resources, i.e., a combination of DL CC and UL CC. A cell consists of DL resources alone or a combination of DL and UL resources. If carrier aggregation is supported, the linkage between the carrier frequency of DL resources (or DL ​​CC) and the carrier frequency of UL resources (or UL CC) is indicated by system information. Carrier frequency means the center frequency of each cell or CC. A cell corresponding to a PCC is called a PCell, and a cell corresponding to a SCC is called a SCell. A carrier corresponding to a PCell in the downlink is a DL PCC, and a carrier corresponding to a PCell in the uplink is a UL PCC. Similarly, a carrier corresponding to a SCell in the downlink is a DL SCC, and a carrier corresponding to a SCell in the uplink is a UL SCC. Depending on the terminal capacity, a serving cell(s) consists of one PCell and zero or more SCells. For a UE in RRC_CONNECTED state but with no carrier aggregation configured or that does not support carrier aggregation, there is only one serving cell consisting of only a PCell.

[0110] As described above, the term cell used in carrier aggregation is different from the term cell referring to a certain geographical area to which communication services are provided by one base station or one antenna group. However, in order to distinguish between a cell referring to a certain geographical area and a cell of carrier aggregation, in the present invention, a cell of carrier aggregation is referred to as CC, and a cell of a geographical area is referred to as cell.

[0111] FIG. 10 is a diagram showing an example in which a cross-carrier scheduling technique is applied. When cross-carrier scheduling is configured, a control channel transmitted through a first CC schedules a data channel transmitted through a first CC or a second CC using a carrier indicator field (CIF). The CIF is included in a DCI. In other words, a scheduling cell is configured, and a DL grant / UL grant transmitted from a PDCCH region of the scheduling cell schedules a PDSCH / PUSCH of a scheduled cell. That is, a search region for multiple component carriers is the PDCCH region of the scheduling cell. A PCell is basically a scheduling cell, and a specific SCell is designated as a scheduling cell by a higher layer.

[0112] In the embodiment of FIG. 10, it is assumed that three DL CCs are merged. Here, it is assumed that DL component carrier #0 is DL PCC (or PCell), and DL component carrier #1 and DL component carrier #2 are DL SCC (or SCell). It is also assumed that DL PCC is configured as PDCCH monitoring CC. If cross-carrier scheduling is not configured by terminal-specific (or terminal-group-specific, or cell-specific) higher layer signaling, the CIF is disabled, and each DL CC transmits only a PDCCH that schedules its own PDSCH without a CIF according to the NR PDCCH rules (non-cross-carrier scheduling, self-carrier scheduling). On the other hand, if cross-carrier scheduling is configured by terminal-specific (or terminal-group-specific, or cell-specific) higher layer signaling, the CIF is enabled, and a specific CC (e.g., DL PCC) transmits not only a PDCCH that schedules the PDSCH of DL CC A but also a PDCCH that schedules the PDSCH of another CC using the CIF (cross-carrier scheduling). In contrast, no PDCCH is transmitted in other DL CCs. Therefore, depending on whether cross-carrier scheduling is configured in the terminal, the terminal monitors a PDCCH that does not include a CIF to receive a self-carrier scheduled PDSCH, or monitors a PDCCH that includes a CIF to receive a cross-carrier scheduled PDSCH.

[0113] 9 and 10 illustrate the subframe structure of the 3GPP LTE-A system, the same or similar structure can be applied to the 3GPP NR system, however, in the 3GPP NR system, the subframes in FIG. 9 and 10 are switched to slots.

[0114] FIG. 11 is a block diagram showing the configuration of a terminal and a base station according to an embodiment of the present invention. In an embodiment of the present invention, the terminal is embodied as various types of wireless communication devices or computing devices that ensure portability and mobility. The terminal is referred to as a UE, a Station (STA), a Mobile Subscriber (MS), etc. In addition, in an embodiment of the present invention, the base station controls and manages cells (e.g., macrocells, femtocells, picocells, etc.) corresponding to a service area, and performs functions such as signal transmission, channel assignment, channel monitoring, self-diagnosis, and relaying. The base station is referred to as a next generation NodeB (gNB) or an Access Point (AP), etc.

[0115] As shown, a terminal 100 according to one embodiment of the present invention includes a processor 110 , a communication module 120 , a memory 130 , a user interface unit 140 , and a display unit 150 .

[0116] First, the processor 110 executes various commands or programs to process data within the terminal 100. The processor 110 also controls the overall operation of the terminal 100 including each unit, and controls the transmission and reception of data between the units. Here, the processor 110 is configured to perform operations according to the embodiments described in the present invention. For example, the processor 110 may receive slot configuration information, determine the slot configuration based thereon, and perform communication according to the determined slot configuration.

[0117] Next, the communication module 120 is an integrated module that performs wireless communication using a wireless communication network and wireless LAN access using a wireless LAN. For this purpose, the communication module 120 includes a plurality of network interface cards (NICs) such as cellular communication interface cards 121 and 122 and an unlicensed band communication interface card 123, either built-in or external. In the drawings, the communication module 120 is shown as an integrated module, but the network interface cards may be arranged independently depending on the circuit configuration or application, unlike the drawings.

[0118] The cellular communication interface card 121 transmits and receives wireless signals to and from at least one of the base station 200, the external device, and the server via the mobile communication network, and provides a cellular communication service in a first frequency band based on instructions from the processor 110. According to an embodiment, the cellular communication interface card 121 includes at least one NIC module that utilizes a frequency band below 6 GHz. The at least one NIC module of the cellular communication interface card 121 independently performs cellular communication with at least one of the base station 200, the external device, and the server according to a cellular communication standard or protocol of the frequency band below 6 GHz supported by the NIC module.

[0119] The cellular communication interface card 122 transmits and receives wireless signals to and from at least one of the base station 200, the external device, and the server using a mobile communication network, and provides a cellular communication service in the second frequency band based on instructions from the processor 110. According to an embodiment, the cellular communication interface card 122 includes at least one NIC module that utilizes a frequency band of 6 GHz or higher. The at least one NIC module of the cellular communication interface card 122 independently performs cellular communication with at least one of the base station 200, the external device, and the server according to a cellular communication standard or protocol of the 6 GHz or higher frequency band supported by the NIC module.

[0120] The unlicensed band communication interface card 123 transmits and receives wireless signals to and from at least one of the base station 200, the external device, and the server through the third frequency band, which is an unlicensed band, and provides communication services in the unlicensed band based on instructions from the processor 110. The unlicensed band communication interface card 123 includes at least one NIC module that utilizes the unlicensed band. For example, the unlicensed band may be a 2.4 GHz or 52.6 GHz band. The at least one NIC module of the unlicensed band communication interface card 123 performs cellular communication with at least one of the base station 200, the external device, and the server, independently or dependently, according to the unlicensed band communication standard or protocol of the frequency band supported by the NIC module.

[0121] The memory 130 stores control programs and various data used by the terminal 100. The control programs include predetermined programs required for the terminal 100 to perform wireless communication with at least one of the base station 200, an external device, and a server.

[0122] Next, the user interface 140 includes various types of input / output means provided in the terminal 100. That is, the user interface unit 140 receives user input using various input means, and the processor 110 controls the terminal 100 based on the received user input. Also, the user interface 140 performs output based on a command from the processor 110 using various output means.

[0123] Then, the display unit 150 outputs various images on a display screen. The display unit 150 outputs various display objects, such as a user interface, based on the contents performed by the processor 110 or a control command of the processor 110.

[0124] The base station 200 according to the embodiment of the present invention also includes a processor 210 , a communication module 220 , and a memory 230 .

[0125] First, the processor 210 executes various commands or programs to process data within the base station 200. The processor 210 also controls the overall operation of the base station 200 including each unit, and controls transmission and reception of data between the units. Here, the processor 210 is configured to perform operations according to the embodiments described in the present invention. For example, the processor 210 may signal slot configuration information and perform communication according to the signaled slot configuration.

[0126] Next, the communication module 220 is an integrated module that performs wireless communication using a wireless communication network and wireless LAN access using a wireless LAN. For this purpose, the communication module 220 includes a plurality of network interface cards, such as cellular communication interface cards 221 and 222 and an unlicensed band communication interface card 223, either built-in or external. In the drawings, the communication module 220 is shown as an integrated module, but the respective network interface cards may be arranged independently depending on the circuit configuration or application, unlike the drawings.

[0127] The cellular communication interface card 221 transmits and receives wireless signals to and from at least one of the terminal 100, the external device, and the server using a mobile communication network, and provides a cellular communication service in a first frequency band according to an instruction of the processor 210. According to an embodiment, the cellular communication interface card 221 includes at least one NIC module that uses a frequency band below 6 GHz. The at least one NIC module of the cellular communication interface card 221 independently performs cellular communication with at least one of the terminal 100, the external device, and the server according to a cellular communication standard or protocol of the frequency band below 6 GHz supported by the NIC module.

[0128] The cellular communication interface card 222 transmits and receives wireless signals to and from at least one of the terminal 100, an external device, and a server using a mobile communication network, and provides a cellular communication service in the second frequency band based on instructions from the processor 210. According to an embodiment, the cellular communication interface card 222 includes at least one NIC module that uses a frequency band of 6 GHz or higher. The at least one NIC module of the cellular communication interface card 222 independently performs cellular communication with at least one of the terminal 100, an external device, and a server according to a cellular communication standard or protocol of the 6 GHz or higher frequency band supported by the NIC module.

[0129] The unlicensed band communication interface card 223 transmits and receives wireless signals to and from at least one of the terminal 100, the external device, and the server using the third frequency band, which is an unlicensed band, and provides communication services in the unlicensed band based on instructions from the processor 210. The unlicensed band communication interface card 223 includes at least one NIC module that uses the unlicensed band. For example, the unlicensed band may be a 2.4 GHz or 52.6 GHz band. The at least one NIC module of the unlicensed band communication interface card 223 performs cellular communication with at least one of the terminal 100, the external device, and the server, independently or dependently, according to the unlicensed band communication standard or protocol of the frequency band supported by the NIC module.

[0130] The terminal 100 and base station 200 shown in FIG. 11 are block diagrams according to an embodiment of the present invention, and the separated blocks are used to logically distinguish the elements of the devices. Thus, the above-mentioned device elements may be mounted on one chip or multiple chips depending on the design of the device. Also, some components of the terminal 100, such as the user interface 150 and the display unit 150, may be selectively provided in the terminal 100. Also, the user interface 140 and the display unit 150 may be additionally provided in the base station 200 as necessary.

[0131] I. Initial connection method for RedCap terminal

[0132] An example of an initial access method is shown in Fig. 12. Hereinafter, Rel-15 and Rel-16 terminals are referred to as legacy type terminals (legacy UEs), and Fig. 12 shows a general initial access process performed by a legacy type terminal.

[0133] Referring to FIG. 12, a terminal receives an SSB from a base station. At this time, a frequency and a time domain in which the SSB can be transmitted may be defined. The terminal can receive the SSB within the frequency and time domain. The SSB is composed of a PSS, an SSS, and a PBCH. The terminal achieves downlink synchronization by receiving the PSS and the SSS, and can know a physical cell ID. The terminal can then receive a master information block (MIB) included in the PBCH by receiving the PBCH.

[0134] The MIB includes the most basic information of a cell and configuration information of a basic CORESET (i.e., CORESET0) and a Type-0 search space. A terminal can monitor and receive a PDCCH based on the configuration information of CORESET0 and the Type-0 search space. The PDCCH can carry DCI format 1_0 in which the CRC is scrambled with SI-RNTI. The DCI format 1_0 can schedule a PDSCH. The PDSCH can deliver SIB1 to a terminal, which includes cell common information required for the terminal to connect to a cell.

[0135] The UE can receive cell common information from SIB1 carried by the PDSCH and can receive configuration information of the PRACH. The UE can transmit the PRACH according to the configuration information of the PRACH. Through the transmission of the PRACH and the subsequent optional access process, the UE can achieve uplink synchronization and receive UE specific information.

[0136] However, a new type of terminal (hereinafter, a RedCap terminal) having reduced capability (RedCap) compared to a legacy type terminal may not be able to establish a cell connection using the initial cell connection procedure according to Fig. 12. This is for the following reasons.

[0137] 1) The receivable bandwidth for a RedCap terminal may be limited. This is because the RedCap terminal can only support a small bandwidth in order to achieve a low product price. However, the bandwidth of the terminal is not taken into consideration in the initial cell connection process as shown in Figure 12. For example, the bandwidth of CORESET0 (shown as CORESET0 BW in Figure 12) may be larger than the bandwidth of the RedCap terminal.

[0138] 2) A RedCap terminal may require higher coverage. The initial cell connection process according to FIG. 12 is determined by the link budget of a legacy type terminal. Therefore, in order for a RedCap terminal to successfully establish an initial cell connection, the initial cell connection process according to FIG. 12 needs to be improved. For example, the PDCCH received in CORESET0 must be able to provide sufficient coverage.

[0139] The following embodiment discloses an improved initial connection process for such a RedCap terminal.

[0140] (1) First Example

[0141] As a first embodiment of the present invention, the RedCap terminal can receive control channel information for an initial cell connection of the RedCap terminal through SIB1.

[0142] FIG. 13 is a diagram illustrating an initial cell connection method according to an embodiment of the present invention.

[0143] Referring to FIG. 13, the RedCap terminal can receive the SS / PBCH (or SSB) of a cell. The RedCap terminal can receive information of the frequency domain of CORESET0 (represented as CORESET0 BW in FIG. 13) or information of the time domain of the Type-0 search space via the SS / PBCH. The RedCap terminal can receive a PDCCH scrambled with SI-RNTI within the CORESET0 or Type-0 search space. The RedCap terminal can receive DCI format 1_0 via the PDCCH. The DCI format 1_0 can include scheduling information of a PDSCH (represented as PDSCH for SIB1 in FIG. 13) carrying SIB1. Thus, the RedCap terminal can receive SIB1 via the PDSCH.

[0144] The RedCap terminal can check whether there is information for the initial cell connection of the RedCap terminal from the received SIB1. The information for the initial cell connection of the RedCap terminal can include information on a CORESET (hereinafter, CORESET-Red) or a search space (hereinafter, search space-Red) for the initial cell connection of the RedCap terminal.

[0145] The RedCap terminal may be configured with frequency resource allocation information or length, or REG, REG bundle, and CCE configuration information of the CORESET (indicated as CORESET-Red in FIG. 13) of the RedCap terminal. The RedCap terminal may be configured with a search space corresponding to CORESET-Red separately from CORESET0. To configure the search space-Red, the terminal may receive information such as a period and offset for monitoring the PDCCH, or an aggregation level of PDCCH candidates and the number of PDCCH candidates per aggregation level.

[0146] If the SIB1 received by the RedCap terminal does not have a CORESET-Red setting for the RedCap terminal or does not have a search space setting corresponding to CORESET-Red, the RedCap terminal can perform at least one of the following operations.

[0147] The first operation includes an operation of determining that the RedCap terminal cannot be connected to the cell if the RedCap terminal cannot receive the settings of CORESET-Red and search space-Red from SIB1.

[0148] The second operation includes an operation in which, when the RedCap terminal cannot receive the CORESET-Red configuration from SIB1, it assumes that the frequency resource allocation information or length of CORESET-Red or the REG, REG bundle, and CCE configuration information are identical to the configuration information of CORESET0.

[0149] The third operation includes an operation in which, when the RedCap terminal cannot receive part of the CORESET-Red configuration from SIB1 but receives part of the CORESET-Red configuration, the unreceived CORESET-Red configuration information is assumed to be the same as the configuration information of CORESET0. For example, when the RedCap terminal receives frequency resource allocation information of CORESET-Red through SIB1 but cannot receive length or REG, REG bundle, or CCE configuration information, it can assume that the length or REG, REG bundle, or CCE configuration information is the same as the length or REG, REG bundle, or CCE configuration information of CORESET0.

[0150] The fourth operation includes, if the RedCap UE cannot receive the configuration of search space-Red from SIB1, assuming that the period and offset of search space-Red or the aggregation level of PDCCH candidates and the number of PDCCH candidates per aggregation level are the same as the configuration of Type-0 search space of the cell, where the Type-0 search space is a search space for monitoring a PDCCH having a CRC scrambled with SI-RNTI.

[0151] The fifth operation includes an operation of assuming that the unreceived configuration information of search space-Red is the same as the configuration information of Type-0 search space when the RedCap terminal receives some but not all of the configurations of search space-Red from SIB1. For example, when the RedCap terminal receives the period and offset of search space-Red using SIB1 but cannot receive the aggregation level of PDCCH candidates and the number of PDCCH candidates per aggregation level, it can assume 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 of search space-Red and the number of PDCCH candidates per aggregation level.

[0152] Furthermore, the RedCap terminal may receive from SIB1 an indication of whether the RedCap terminal is able to connect to the cell.

[0153] For example, the indicator may indicate whether the RedCap terminal can perform cell connection or not. If the indicator indicates that the RedCap terminal cannot perform cell connection, the RedCap terminal cannot perform cell connection on the PRACH resource received from SIB1.

[0154] As another example, the indicator may indicate that the RedCap terminal can perform cell connection using CORESET-Red or search space-Red, or that the RedCap terminal cannot perform cell connection using CORESET-Red or search space-Red. If the indicator indicates that the RedCap terminal cannot perform cell connection using CORESET-Red or search space-Red, the RedCap terminal can perform cell connection using the PRACH resource received from SIB1.

[0155] As another example, the indicator may indicate whether a cell connection is possible using the PRACH set by the RedCap terminal in SIB1. If the indicator indicates that a cell connection is possible using the PRACH set by the RedCap terminal in SIB1, the RedCap terminal may perform a cell connection using the PRACH resource received from SIB1.

[0156] The way in which the RedCap terminal receives CORESET-Red and search space-Red information using SIB1 is as follows.

[0157] As a first method, the information of CORESET-Red and search space-Red for a RedCap terminal may be the same as that for setting CORESET0 or Type-0 search space in PBCH. That is, the information of CORESET-Red and search space-Red may be 8 bits. Of the 8 bits, 4 bits may indicate CORESET-Red information, and the remaining 4 bits may indicate search space-Red information. The 4-bit information of CORESET-Red indicates one of 16 combinations. The 4-bit search space-Red indicates one of 16 combinations. Although 8 bits are described here, if 8 bits are not sufficient, it may be extended to any integer number of bits.

[0158] Second, the information on CORESET-Red and search space-Red for RedCap terminals can be taken in the same way as constructing the existing CORESET and search space.

[0159] As an example, the information of CORESET-Red may include frequency information of CORESET-Red.

[0160] In one aspect, the frequency information of CORESET-Red may include an offset of a PRB based on CORESET0. That is, the frequency information (allocated PRB) of CORESET-Red may be a PRB obtained by adding an offset to the PRB of CORESET0.

[0161] In another aspect, the frequency information of CORESET-Red may include a common PRB index of the cell, where the common PRB index of the cell is a PRB index commonly used by terminals in the cell, and a frequency corresponding to common PRB index 0 may be received from SIB1. The terminal may start indexing from the common PRB index 0. The information of CORESET-Red may indicate a starting index of a PRB using the common PRB index.

[0162] As another example, the information on CORESET-Red may include the length (number of symbols) of CORESET-Red. The length may include 1, 2, or 3 symbols. In addition to the length, it may include 6 to 12 symbols. The length (number of symbols) of CORESET-Red may include a value compared with CORESET0. For example, the length (number of symbols) of CORESET-Red may include information indicating whether it is the same as the length (number of symbols) of CORESET0. The length (number of symbols) of CORESET-Red may be indicated by a difference with the length (number of symbols) of CORESET0. That is, it may include information corresponding to the length (number of symbols) of CORESET-Red - the length (number of symbols) of CORESET0. In general, 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 include only non-negative integers.

[0163] As yet another example, the information of CORESET-Red may include information on whether or not to perform interleaving on REG-to-CCE mapping. If interleaving is not performed, REGs (REG bundles) for RedCap terminals may be sequentially grouped as CCEs. If interleaving is performed, indexes of REGs (REG bundles) for RedCap terminals may be interleaved, and the interleaved indexes may be sequentially grouped as CCEs.

[0164] As yet another example, the information of CORESET-Red may include size setting information of the REG bundle. The size of the REG bundle represents the number of REGs included in one REG bundle. The REGs may be grouped according to the size of the REG bundle. The RedCap terminal may assume that the same precoding is applied to the REGs included in the REG bundle. Therefore, the RedCap terminal may reduce channel estimation errors by joint detection of the DM-RSs of the REGs included in the REG bundle.

[0165] For higher channel estimation performance, CORESET-Red can include additional information. Based on the additional information, the RedCap terminal can assume that the same precoding is used between different CCEs. Here, the different CCEs may be adjacent CCEs in the frequency domain. For example, when the indexes of CCEs are determined sequentially in the frequency domain, such as 0, 1, 2, ..., the RedCap terminal can assume that adjacent CCEs in the frequency domain, such as CCE0 and CCE1, use the same precoding, based on the additional information. Then, it can assume that the next adjacent CCEs, such as CCE2 and CCE3, use the same precoding. By assuming that the same precoding is used for multiple CCEs adjacent in the frequency domain in this way, the channel estimation performance can be improved.

[0166] Here, application of the same precoding may be limited to CCEs included in one PDCCH candidate. That is, the RedCap terminal may assume that the same precoding is used only for CCEs included in one PDCCH candidate. And, the RedCap terminal may assume that different precoding is used for CCEs included in different PDCCH candidates.

[0167] As an example, the search space-Red may include periodicity and offset information. The periodicity and offset may include at least one time unit among a slot unit, a slot group unit, a symbol unit, and a symbol group unit. The RedCap terminal may further be indicated an index of a symbol at which monitoring of the PDCCH starts within each time unit. If the unit of the periodicity and offset information is a slot unit, the index of the starting symbol may 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 periodicity and offset information is not a slot but another time unit, a bitmap corresponding to the number of symbols included in the time unit may be indicated. The MSB of the bitmap may indicate the first symbol of the symbols included in the time unit, and the LSB may indicate the last symbol of the symbols included in the time unit. The RedCap terminal may determine a monitoring occasion for monitoring the PDCCH from the periodicity and offset value or the start index. The RedCap terminal must blindly decode the PDCCH at the symbols corresponding to the monitoring occasion.

[0168] As another example, the search space-Red may include information about additional monitoring occasions where the PDCCH monitored by the RedCap terminal at the monitoring occasion can be repeatedly received. The terminal can monitor and receive the first PDCCH at the monitoring occasion. However, when sufficient reception is not possible with only one first PDCCH, the first PDCCH can be repeatedly received at another monitoring occasion to improve the reception performance of the PDCCH. Therefore, information about additional monitoring occasions where the first PDCCH can be repeatedly received may be necessary.

[0169] Additional monitoring opportunities may be provided by:

[0170] In a first method, the additional monitoring opportunity may be repeated for each time unit and may be indicated by the number of time units. Here, the time unit may include at least one of a slot, a set of slots, a symbol, and a set of symbols. For example, assume that the time unit is a slot. In the first method, the additional monitoring opportunity may be indicated by the number of slots (K). In this case, the first PDCCH monitored and received by the RedCap terminal in the monitoring opportunity of the first slot may be repeatedly received in the next slot at the same symbol starting position as the first slot. The RedCap terminal can repeatedly receive the PDCCH for the number of slots (K) indicated in this manner. The same method may be used in the case of a time unit other than a slot.

[0171] As a second method, the additional monitoring opportunity may be repeated at the symbol immediately following the monitoring opportunity, and may be indicated by the number of repetitions (K). For example, assuming that a monitoring opportunity is set in one slot, the additional monitoring opportunity may be located at the symbol immediately following the symbol in the one slot in which the monitoring opportunity ends. And the additional monitoring opportunity may be located at the symbol immediately following the symbol in which the additional monitoring opportunity ends. In this way, the additional monitoring opportunity may be located consecutively according to the number of repetitions (K).

[0172] Referring again to FIG. 13, the RedCap terminal that receives information on CORESET-Red or search space-Red from SIB1 can receive PDCCH within the CORESET-Red and search space-Red. The PDCCH can schedule PDSCH. The PDSCH can carry SIB1 (hereinafter, SIB1-Red) including system information that the RedCap terminal must further receive. Therefore, the RedCap terminal can receive SIB1-Red, which is system information required for the initial cell connection of the RedCap terminal, by receiving PDCCH according to information on CORESET-Red or search space-Red and receiving PDSCH scheduled by the PDCCH. SIB1-Red can include information regarding PRACH for cell connection of the RedCap terminal. For convenience, the PRACH used by the RedCap terminal for cell connection can be called PRACH-Red.

[0173] In order to receive SIB1-Red, the RedCap terminal needs to be indicated by the PDCCH the time-frequency resource on which the PDSCH is scheduled. In order to receive the frequency resource (i.e., PRB), the RedCap terminal needs to know the active downlink BWP. Or, the RedCap terminal needs to set the active downlink BWP. The method related to this is as follows.

[0174] As a first method, the RedCap terminal does not need to set a separate active downlink BWP from SIB1, and does not need to determine the frequencies from the lowest frequency PRB to the highest frequency PRB indicated by CORESET-Red in SIB1 as the active downlink BWP of the RedCap terminal.

[0175] As a second method, the UE may be configured with an active downlink BWP for the RedCap UE from SIB1, where the active downlink BWP includes the band of CORESET-Red.

[0176] In the above description, SS / PBCH, CORESET0, CORESET-Red, etc. are downlink signals or channels. Therefore, the downlink signals or channels may be included in the downlink BWP of the downlink cell. On the other hand, PRACH or PRACH-Red is an uplink channel, so it may be included in the uplink BWP of the uplink cell. Therefore, in addition to the information of CORESET-Red and search space-Red, time-frequency domain information for the transmission of PRACH-Red may be further required.

[0177] Also, the PRACH may use different subcarrier spacing. For example, the PRACH may have a smaller subcarrier spacing to have a longer symbol length. The PUSCH and PUCCH transmitting uplink data or control information may use subcarrier spacing of 15 kHz, 30 kHz, 60 kHz, or 120 kHz, whereas the PRACH may have a subcarrier spacing of 1.25 kHz or 5 kHz. As a result, signals or channels having different subcarrier spacings may be mixed in an uplink cell. In this case, a guard band is required to suppress interference between signals or channels having adjacent subcarrier spacings. Therefore, when the PRACH is distributed in time-frequency resources, waste of uplink resources due to the guard band may occur. To prevent this, the PRACH used by the legacy type terminal and the PRACH used by the RedCap terminal need to be arranged in time-frequency resources as adjacent as possible.

[0178] Hereinafter, this embodiment discloses a method for arranging the PRACH of a legacy type terminal and the PRACH-Red of a RedCap terminal in adjacent time-frequency resources in an uplink cell.

[0179] The first method is described with reference to FIG. 14, the second method is described with reference to FIG. 15, and the third method is described with reference to FIG.

[0180] FIG. 14 is a diagram illustrating an initial cell connection method and PRACH resource configuration according to one embodiment of the present invention.

[0181] Referring to FIG. 14, the RedCap terminal may determine that the PRACH-Red is located in time adjacent to the PRACH of the legacy type terminal (see the TDM notation in FIG. 14). In this case, there is no need to configure separate frequency information for the PRACH-Red. In this case, the frequency information for the PRACH-Red may be the same as the frequency information for the PRACH. That is, the frequency occupied by the PRACH and the frequency occupied by the PRACH-Red may be the same. Separate time information for the PRACH-Red may be configured in the RedCap terminal.

[0182] Here, the time information may include information on whether PRACH-Red is located immediately before or immediately after PRACH. If it is located immediately after, PRACH-Red may start at the time (or the slot) immediately after PRACH ends. If it is located immediately before, PRACH-Red may end at the time (or the slot) immediately before PRACH starts.

[0183] Alternatively, the time information may indicate a time difference between the PRACH and the PRACH-Red. More specifically, the time information may include a time difference or interval (number of symbols or number of slots) between the last time point of the PRACH and the first time point of the PRACH-Red. Alternatively, the time information may include a time difference or interval (number of symbols or number of slots) between the last time point of the PRACH-Red and the first time point of the PRACH. Alternatively, the time information may include a time difference or interval (number of symbols or number of slots) between the first time point of the PRACH and the first time point of the PRACH-Red.

[0184] FIG. 15 is a diagram illustrating an initial cell connection method and PRACH resource configuration according to another embodiment of the present invention.

[0185] Referring to FIG. 15, the RedCap terminal may determine that the PRACH-Red is located in a frequency adjacent to the PRACH of the legacy type terminal. Here, there is no need to set separate time information for the PRACH-Red. In this case, the time information for the PRACH-Red may be the same as the time information for the PRACH. That is, the time (slot and symbol) occupied by the PRACH and the time (slot and symbol) occupied by the PRACH-Red may be the same. The RedCap terminal may be set with separate frequency information for the PRACH-Red.

[0186] Here, the frequency information may include information regarding whether the PRACH-Red is at a frequency just below or just above the PRACH.

[0187] Alternatively, the frequency information may indicate a frequency difference between the PRACH and the PRACH-Red. More specifically, the frequency information may include a frequency difference or interval between the top frequency of the PRACH and the bottom frequency of the PRACH-Red (the number of PRBs or the number of subcarriers in units of the subcarrier spacing of the PRACH or the number of subcarriers in units of the subcarrier spacing of the uplink BWP of the uplink cell). Alternatively, the frequency information may include a frequency difference or interval between the top frequency of the PRACH-Red and the bottom frequency of the PRACH (the number of PRBs or the number of subcarriers in units of the subcarrier spacing of the PRACH or the number of subcarriers in units of the subcarrier spacing of the uplink BWP of the uplink cell). Alternatively, the frequency information may include a frequency difference or interval between the bottom frequency of the PRACH and the bottom frequency of the PRACH-Red (the number of PRBs or the number of subcarriers in units of the subcarrier spacing of the PRACH or the number of subcarriers in units of the subcarrier spacing of the uplink BWP of the uplink cell).

[0188] FIG. 16 is a diagram illustrating an initial cell connection method and PRACH resource configuration according to yet another embodiment of the present invention.

[0189] Referring to FIG. 16, the RedCap terminal may determine that the PRACH-Red is located at the same time-frequency as the PRACH of the legacy type terminal. The RedCap terminal may not need to set separate time-frequency information for the PRACH-Red. In this case, the time-frequency information of the PRACH-Red may be the same as the time-frequency information of the PRACH. The RedCap terminal may use some of the PRACHs of the time-frequency. For example, the PRACH of the legacy type terminal may be configured with a plurality of PRACH preamble sequences. In this case, some of the plurality of PRACH preamble sequences may be used by the RedCap terminal.

[0190] For this purpose, the RedCap terminal may be configured with an index (or ID) of a usable sequence among the PRACH preamble sequences. More specifically, the RedCap terminal may be configured with the lowest index (or ID) among the usable sequence indexes (or IDs), and may use sequences having that index (or ID) and subsequent indexes (or IDs).

[0191] As yet another example, the RedCap terminal may be configured with a number of available sequences, and may use as many sequences as there are available sequences with high indexes (or IDs) among all sequences.

[0192] (2) Second Example

[0193] According to the second embodiment of the present invention, the RedCap terminal can receive scheduling information of system information for the initial cell connection of the RedCap terminal from SIB1. Here, the system information for the initial cell connection of the RedCap terminal is referred to as SIB1-Red. This is shown in FIG.

[0194] FIG. 17 is a diagram illustrating an initial cell connection method according to another embodiment of the present invention.

[0195] Referring to FIG. 17, the RedCap terminal can receive the SS / PBCH (or SSB) of a cell. The RedCap terminal can receive frequency domain information of CORESET0 or time domain information of Type-0 search space in the SS / PBCH. The RedCap terminal can receive a PDCCH scrambled with SI-RNTI in the CORESET0 or Type-0 search space. The RedCap terminal can receive DCI format 1_0 in the PDCCH. The DCI format 1_0 can include scheduling information of a PDSCH carrying SIB1. Therefore, the RedCap terminal can receive SIB1 (referred to as PDSCH for SIB1 in FIG. 17).

[0196] The SIB1 received by the RedCap terminal may include information for cell connection of the legacy type terminal. The legacy type terminal does not need to separately receive system information for the RedCap terminal. Therefore, when system information for the RedCap terminal is added to the existing SIB1, the overhead of SIB1 may increase. In order to prevent this, it is preferable that the system information required by the RedCap terminal is transmitted separately. Therefore, the SIB1 may include time-frequency information of the PDSCH that allows the RedCap terminal to receive the system information required by the RedCap terminal. The RedCap terminal can receive the PDSCH according to the time-frequency information. The received PDSCH may include SIB1-Red (represented as PDSCh for SIB1-Red in FIG. 17). The RedCap terminal can receive information for initial cell connection by receiving SIB1-Red. For example, the RedCap terminal can know the setting of PRACH-Red for initial cell connection based on SIB1-Red.

[0197] In order to receive allocation of a frequency resource (i.e., a PRB) in which a PDSCH for SIB1-Red is scheduled, the RedCap terminal needs to know an active downlink BWP in which a PDSCH is scheduled (denoted as RedCap BW in FIG. 17). Therefore, an active downlink BWP needs to be configured in the RedCap terminal.

[0198] As an example, the RedCap UE may be configured with an index and length of a start PRB (PRB with the lowest frequency) of an active downlink BWP from SIB1. Here, the PRB index may be indicated by a common PRB index. Alternatively, the PRB index may be indicated by a frequency interval (number of PRBs) from CORESET0. That is, since the RedCap UE knows the frequency range occupied by CORESET0, it can determine the start PRB of an active downlink BWP by adding a given frequency interval (number of PRBs) to the frequency range.

[0199] The length may be set to at least one of 24 PRBs, 48 ​​PRBs, and 96 PRBs. As another example, the length may be the same as the number of PRBs included in CORESET0. In this case, information about the length of an active downlink BWP in SIB1 may be omitted.

[0200] The RedCap UE may assume that a PDSCH carrying SIB1-Red is received within the configured active downlink BWP.

[0201] (3) Third Example

[0202] According to the third embodiment of the present invention, the RedCap terminal can receive configuration information of the PRACH for the initial cell connection of the RedCap terminal from SIB1. Here, the PRACH for the initial cell connection of the RedCap terminal is called PRACH-Red. This is shown in FIG.

[0203] FIG. 18 is a diagram illustrating an initial cell connection method according to still another embodiment of the present invention.

[0204] Referring to FIG. 18, the RedCap terminal can receive the SS / PBCH (or SSB) of the cell. The RedCap terminal can receive frequency domain information of CORESET0 or time domain information of Type-0 search space in the SS / PBCH. The RedCap terminal can receive a PDCCH scrambled with SI-RNTI in the CORESET0 or Type-0 search space. The RedCap terminal can receive DCI format 1_0 in the PDCCH. The DCI format 1_0 can include scheduling information of PDSCH for SIB1. Therefore, the RedCap terminal can receive SIB1 (denoted as PDSCH for SIB1 in FIG. 18).

[0205] The SIB1 received by the RedCap terminal may include information for cell connection of the legacy type terminal. The SIB1 may further include system information for the RedCap terminal. Therefore, the RedCap terminal can obtain information regarding the initial cell connection of the RedCap terminal from the SIB1 without receiving separate system information (e.g., SIB1-Red in FIG. 17). For example, the SIB1 may include configuration information of the PRACH-Red for the initial cell connection.

[0206] The RedCap terminal may be configured with an uplink BWP for the configuration of the PRACH-Red and cell connection. The PRACH-Red may be transmitted within the uplink BWP. Thus, the configuration of the PRACH-Red is included in the uplink BWP. The uplink BWP for the RedCap terminal in SIB1 may be configured as follows.

[0207] (4) Fourth Example

[0208] According to the fourth embodiment of the present invention, the RedCap terminal can receive the SS / PBCH for the RedCap terminal only. This may be distinguished from the SS / PBCH received by the legacy type terminal. The method of distinction will be described later. For convenience, the SS / PBCH that can be received only by the RedCap terminal is called SSB-Red. This is shown in FIG.

[0209] FIG. 19 is a diagram illustrating an initial cell connection method according to still another embodiment of the present invention.

[0210] Referring to FIG. 19, the RedCap terminal can receive SSB-Red, which is an SS / PBCH for the RedCap terminal only, in a BWP (represented as RedCap BW in FIG. 19) for the RedCap terminal only. By receiving the SSB-Red, the RedCap terminal can receive downlink signal synchronization, cell ID, and MIB (Master Information Block) transmitted in the PBCH. By receiving the SSB-Red, the RedCap terminal can obtain configuration information of CORESET-Red or search space-red that monitors a PDCCH that schedules a PDSCH that transmits SIB1-Red. The RedCap terminal can monitor and receive a PDCCH in CORESET-Red or search space-red. By receiving the PDCCH, the RedCap terminal can receive a PDSCH (represented as PDSCH for SIB1-Red in FIG. 19) that transmits SIB1-Red. The RedCap terminal can receive configuration information of PRACH-Red for cell connection from SIB1-Red, and can transmit a PRACH according to the configuration information of PRACH-Red.

[0211] In the fourth embodiment, the RedCap terminal must receive SSB-Red in a separate BWP that is different from the downlink BWP of the legacy type terminal. However, since the time when the SSB-Red is received is before the cell connection stage, the RedCap terminal does not know at what frequency and when the SSB-Red is transmitted. In addition, the RedCap terminal must be able to distinguish between the SS / PBCH and SSB-Red received by the legacy type terminal. A method for this purpose will be disclosed below.

[0212] The first method includes a process in which the RedCap terminal performs an initial cell connection process together with a legacy type terminal. For example, the RedCap terminal can receive the SS / PBCH (or SSB) of the cell. The RedCap terminal can receive frequency domain information of CORESET0 or time domain information of Type-0 search space in the SS / PBCH. The RedCap terminal can receive a PDCCH scrambled with SI-RNTI using the information of CORESET0 or Type-0 search space. The RedCap terminal can receive DCI format 1_0 in the PDCCH. The DCI format 1_0 can include scheduling information of a PDSCH carrying SIB1. Thus, the RedCap terminal can receive SIB1. The SIB1 can include information on the frequency and time at which SSB-Red is transmitted. That is, the terminal may be configured with information for receiving SSB-Red for the RedCap terminal by SIB1.

[0213] The frequency of SSB-Red may be indicated by an absolute radio frequency channel number (ARFCN). Alternatively, the frequency of SSB-Red may be indicated by a common PRB index. Alternatively, the frequency of SSB-Red may be indicated by an interval with respect to the frequency of SSB. Here, the interval may be indicated by a frequency. Here, the interval may be indicated by a number of PRBs. Here, the interval may be indicated by a number of subcarriers. Here, the interval may be indicated by a number of channel rasters or a number of synchronization rasters between SSB and SSB-Red.

[0214] The time of SSB-Red may be the same as that of SSB. That is, SSB and SSB-Red may be transmitted at the same time (slot and symbol). As another example, the time of SSB-Red may have a fixed time interval with respect to SSB. For example, the fixed time interval may be given as 5 ms (length of a half frame). Due to the fixed time interval between SSB and SSB-Red, the RedCap terminal can receive SSB in the first time interval and SSB-Red in the second time interval. This allows the terminal to receive two synchronization blocks and achieve downlink synchronization more accurately.

[0215] The second method involves SSB-Red having a different structure than SSB for legacy type terminals.

[0216] As an example, SSB-Red may be designed to include a larger frequency band in order to improve the reception performance of the PBCH. For example, SSB-Red may be designed to include 4 more PRBs than SSB of a legacy type terminal. That is, SSB-Red may be designed to occupy 24 PRBs. More specifically, SSB-Red may have 4 symbols. Of the 4 symbols, the first symbol transmits a PSS, and the third symbol transmits an SSS. Then, the PBCH may be transmitted in the resources other than the resources to which the SSS is mapped, among the 24 PRBs of the second and fourth symbols, and the 24 PRBs of the third symbol. Although the above example has been described as 24 PRBs, it may be extended to more PRBs.

[0217] The RedCap terminal can receive the PSS and SSS to obtain downlink signal synchronization and a cell ID. The RedCap terminal can decode the PBCH assuming 20 PRBs to determine whether the SS / PBCH is an SSB configured with 20 PRBs or an SS / PBCH designed with more PRBs (SSB-Red), and can decode the PBCH as a PBCH designed with more PRBs. If PBCH decoding is successful assuming 20 PRBs, the terminal can determine that the SS / PBCH is an SSB of a general terminal (legacy). If PBCH decoding is successful assuming more PRBs, the RedCap terminal can determine that the SS / PBCH is an SSB-Red of the RedCap.

[0218] As another example, SSB-Red may be designed to include more symbols to improve the reception performance of the PBCH. For example, SSB-Red may be designed to include one or two more symbols than the symbols of a legacy type terminal. That is, SSB-Red may be designed to include five or six symbols. The first symbol is used to transmit the PSS, and the third symbol is used to transmit the SSS. Then, the PBCH may be transmitted at the second, fourth, fifth, or sixth symbol.

[0219] The RedCap terminal can receive the PSS and SSS to obtain downlink signal synchronization and a cell ID. The RedCap terminal can decode the PBCH by assuming four symbols to determine whether the SS / PBCH is an SS / PBCH (SSB) consisting of four symbols or a PBCH (SSB-Red) designed with more symbols, and can decode the PBCH as a PBCH designed with more symbols. If the PBCH decoding is successful assuming four symbols, the terminal can determine that the SS / PBCH is an SSB of a general terminal (legacy). If the PBCH decoding is successful assuming more symbols, the terminal can determine that the SS / PBCH is an SSB-Red of the RedCap.

[0220] As another example, SSB and SSB-Red may be distinguished according to the order of symbols to which SS / PBCH are mapped. For example, unlike SSB, SSB-Red may have a PSS located in the first symbol, and the position of the SSS moved to the second or fourth symbol. If the SSS is moved to the second symbol, the PBCH may be transmitted in the 20 PRBs of the third and fourth symbols, and in the PRBs of the 20 PRBs of the second symbol that are not occupied by the SSS. If the SSS is moved to the fourth symbol, the PBCH may be transmitted in the 20 PRBs of the second and third symbols, and in the PRBs of the 20 PRBs of the fourth symbol that are not occupied by the SSS.

[0221] The RedCap terminal can receive the PSS. The RedCap terminal can then determine the symbol in which the SSS is transmitted to determine whether the SSB is a legacy type terminal's SSB or a RedCap terminal's SSB-Red. If the SSS is received in the third symbol, the terminal knows that the SS / PBCH is a general terminal (legacy) SSB. If the SSS is received in the second or fourth symbol, the terminal knows that the SS / PBCH is a RedCap SSB-Red.

[0222] As yet another example, SSB and SSB-Red may be distinguished using a physical cell ID obtained from the SS / PBCH. For example, the SS / PBCH may have a maximum of 1008 physical cell IDs. The RedCap terminal may determine that a particular value among the maximum of 1008 physical cell IDs is SSB-Red. For example, the particular value may be a physical cell ID that leaves a remainder of 0 when divided by 3. As yet another example, the physical cell ID may be a number between N cell ID =3*N (1) ID +N (2) ID Since it has the form (1) ID Or N (2) ID is a specific value, it can be determined to be SSB-Red. As yet another example, the number of physical cell IDs that an SS / PBCH can have may be increased to 1008 or more. In this case, the RedCap terminal can determine that the SS / PBCH is SSB-Red if the physical cell ID is a value of 1008 or more.

[0223] As yet another example, SSB and SSB-Red may be distinguished according to the RE mapping order of PBCH in SS / PBCH. For example, if the PBCH of the SSB of a legacy type terminal is mapped in a first direction (e.g., from a low frequency RE to a high frequency RE), the PBCH of the SSB-Red of a RedCap terminal may be mapped in a second direction (e.g., in the opposite direction, from a high frequency RE to a low frequency RE). Here, the second direction may be different from the first direction. From the RE mapping of the PBCH, the terminal can determine whether the SSB is an SSB of a legacy type terminal or an SSB-Red of a RedCap terminal.

[0224] The RedCap terminal can receive the PSS and SSS to obtain downlink signal synchronization and a cell ID. The RedCap terminal can decode the PBCH assuming the first direction to determine whether it is an SS / PBCH (SSB) mapped to the first direction or a PBCH (SSB-Red) designed for the second direction, and can decode it as a PBCH designed for the second direction. If the PBCH decoding is successful assuming the first direction, the terminal can determine that the SS / PBCH is an SSB of a general terminal (legacy). If the PBCH decoding is successful assuming the second direction, the terminal can determine that the SS / PBCH is an SSB-Red of the RedCap.

[0225] As another example, in the SS / PBCH, the SSB and SSB-Red may be distinguished by the CRC of the PBCH. For example, if the PBCH of the SSB of a legacy type terminal is scrambled with a first CRC, the PBCH of the SSB-Red of a RedCap terminal may be scrambled with a second CRC different from the first CRC. The terminal can determine whether the SSB is the SSB of a legacy type terminal or the SSB-Red of a RedCap terminal by checking the CRC value of the PBCH.

[0226] The RedCap terminal can receive the PSS and SSS to obtain downlink signal synchronization and a cell ID. The RedCap terminal can decode the PBCH assuming the first CRC and decode the PBCH assuming the second CRC to determine whether the SS / PBCH is scrambled with the first CRC (SSB) or the PBCH is scrambled with the second CRC. If the PBCH decoding is successful assuming the first CRC, the terminal can determine that the SS / PBCH is an SSB of a legacy type terminal. If the PBCH decoding is successful assuming the second CRC, the terminal can determine that the SS / PBCH is an SSB-Red of the RedCap.

[0227] As yet another example, in the SS / PBCH, SSB and SSB-Red may be distinguished by one bit of the PBCH. The PBCH of the SSB of a legacy type terminal may have one unused bit. Therefore, depending on the value of the one bit, it can be determined whether it is an SSB of a legacy type terminal or an SSB-Red of a RedCap terminal. For example, if the value of the one bit in the PBCH is "0", the RedCap terminal can determine that the SSB is an SSB of a legacy type terminal, and if the value is "1", it can determine that the SSB is an SSB-Red of a RedCap terminal.

[0228] In the previous example, the RedCap terminal can only determine whether the SSB is that of a legacy type terminal or that of a RedCap terminal after receiving the PSS, SSS, and PBCH, which may lead to additional reception overhead and battery consumption.

[0229] As yet another example, the frequency at which SSB-Red may be transmitted may be different from the frequency at which SSB is transmitted. For example, a terminal may receive SSB at a fixed frequency interval in order to receive the correct SSB. Here, the fixed frequency interval may be defined as a synchronization raster. This allows the terminal to receive SSB sparsely at a fixed frequency interval (e.g., tens of kHz to hundreds of kHz) rather than receiving SSB at all frequencies in order to reduce battery consumption of the terminal. The base station transmits SSB at a fixed frequency interval in order for the terminal to receive SSB correctly. In other words, there may be a frequency band in which the terminal does not monitor SSB. The base station can transmit SSB-Red in that frequency band, and the RedCap terminal can receive SSB-Red in that frequency band.

[0230] As yet another example, the time interval in which SSB-Red may be transmitted may be different from the time interval in which SSB is transmitted. For example, the terminal may receive the SSB within a 5 ms half frame of a 10 ms radio frame in order to receive the correct SSB. In other words, there may be a time interval in which the terminal does not monitor the SSB. For example, if the SSB is transmitted within a 5 ms half frame of a 10 ms radio frame, the remaining time interval is an interval in which the SSB is not monitored. In that time interval, the base station may transmit SSB-Red, and in that time interval, the RedCap terminal may receive SSB-Red.

[0231] (5) Fifth Example

[0232] According to the fifth embodiment of the present invention, the RedCap terminal can interpret the information indicated by the SS / PBCH differently from the legacy type terminal. Here, the SS / PBCH can be received by both the legacy type terminal and the RedCap terminal. That is, the structure of the SS / PBCH can be the same as the SSB of the legacy type terminal. This is shown in FIG.

[0233] FIG. 20 is a diagram illustrating an initial cell connection method according to still another embodiment of the present invention.

[0234] Referring to FIG. 20, the legacy type terminal and the RedCap terminal can receive SS / PBCH. By receiving PSS and SSS, it is possible to receive downlink signal synchronization and a physical cell ID. And, the legacy type terminal and the RedCap terminal can receive PBCH. In this case, the legacy type terminal and the RedCap terminal can interpret the PBCH in different ways.

[0235] A legacy type terminal can receive configuration information of CORESET0 and configuration information of Type-0 search space using 8 bits of PBCH. At this time, 4 bits indicating frequency configuration information of CORESET0 can indicate one of 16 combinations. And, 4 bits indicating configuration information of Type-0 search space can indicate one of 16 combinations. If the 4 bits indicate '0000', it indicates the first combination of 16 combinations. In this way, using a total of 8 bits of 4 bits and 4 bits, the terminal can receive a PDCCH that schedules a PDSCH that transmits SIB1.

[0236] The Redcap terminal can interpret the 8 bits of the PBCH differently. The 4 bits indicating the configuration information of CORESET0 can be reinterpreted and used as the configuration information of CORESET-Red. That is, the configuration information of CORESET-Red is indicated by 4 bits, and can indicate one of 16 combinations. The 4 bits indicating the configuration information of Type-0 search space can be reinterpreted and used as the configuration information of search space-Red.

[0237] For example, when the 4 bits indicating the configuration information of CORESET0 indicate "0000", the terminal operates as follows. If the terminal is a legacy type terminal, it determines that the 4 bits indicate one of the 16 combinations indicating the configuration information of CORESET0. In other words, if the 4 bits are "0000", it determines that the combination is the first of the 16 combinations indicating the configuration information of CORESET0. If the terminal is a RedCap terminal, it determines that the 4 bits indicate one of the 16 combinations indicating the configuration information of CORESET-Red. In other words, if the 4 bits are "0000", it determines that the combination is the first of the 16 combinations indicating the configuration information of CORESET-Red.

[0238] The terminal may be instructed as to whether or not to perform the reinterpretation. For example, one bit of the PBCH may be used to instruct whether or not the RedCap terminal can reinterpret information received on the PBCH in a manner suitable for the RedCap terminal. If the one bit is "0", the RedCap terminal must not reinterpret information received on the PBCH. If the one bit is "1", the RedCap terminal can reinterpret information received on the PBCH.

[0239] (6) Sixth Example

[0240] According to the sixth embodiment of the present invention, the RedCap terminal can determine the configuration information of CORESET-Red based on CORESET0. More specifically, the RedCap terminal can receive SS / PBCH to obtain the configuration information of CORESET0. The RedCap terminal can infer the configuration information of CORESET-Red based on the configuration information of CORESET0.

[0241] As an example, it can be assumed that CORESET-Red starts at the symbol immediately following the symbol at which CORESET0 ends. Here, CORESET-Red may have the same configuration as CORESET0. That is, the number of PRBs, the positions of PRBs, and the length of CORESET may be the same as CORESET0. It can be assumed that CORESET-Red starts at the slot immediately following the slot to which CORESET0 belongs. Here, CORESET-RED may have the same configuration as CORESET0. That is, the number of PRBs, the positions of PRBs, and the length of CORESET may be the same as CORESET0. Also, the position of the symbol at which CORESET-Red starts within a slot may be the same as the position at which CORESET0 starts within a slot. Here, it is expressed as the immediately following symbol or the immediately following slot, but it may be more expanded to apply after a certain number of symbols or after a certain number of slots. Also, it has been described that CORESET-Red is located after CORESET0, but conversely, CORESET-Red may be located before CORESET0.

[0242] As another example, it can be assumed that CORESET-Red starts in the PRB immediately above the PRB where CORESET0 ends. Here, CORESET-Red may have the same configuration as CORESET0. That is, the number of PRBs or the length of CORESET may be the same as CORESET0. Here, it is stated that CORESET-Red starts in the PRB immediately above, but in a more expanded sense, CORESET-Red may start after a certain number of PRBs. Also, here, CORESET-Red may be located immediately below the PRB where CORESET0 starts.

[0243] (7) Seventh Example

[0244] In a seventh embodiment of the present invention, a legacy type terminal and a RedCap terminal can monitor different PDCCH candidates in CORESET0. Here, CORESET0 is indicated by SS / PBCH. A legacy type terminal and a RedCap terminal can receive CORESET0 configuration information in the same manner without distinction. This is shown in FIG.

[0245] FIG. 21 is a diagram illustrating an initial cell connection method according to still another embodiment of the present invention.

[0246] 21, a legacy type terminal may receive a PDCCH that schedules SIB1 in CORESET0. This PDCCH may carry DCI format 1_0.

[0247] The RedCap terminal can receive a PDCCH carrying SIB1-Red in CORESET0. This PDCCH can carry DCI format X. The method of configuring DCI format X is as follows.

[0248] As a first method, the lengths of DCI format 1_0 and DCI format X may be different from each other. That is, the legacy type terminal blindly decodes DCI format 1_0 having a first length, and therefore can receive DCI format 1_0, but does not need to receive DCI format X. Conversely, the RedCap terminal blindly decodes DCI format X having a second length, and therefore can receive DCI format X, but does not need to receive DCI format 1_0. The RedCap terminal further blindly decodes DCI format 1_0 having a first length to receive DCI format 1_0, and can receive SIB1 scheduled by DCI format 1_0.

[0249] As a second method, the CRCs of DCI format 1_0 and DCI format X may be scrambled with different values. For example, the CRC of DCI format 1_0 may be scrambled with SI-RNTI, but DCI format X may be scrambled with a value different from SI-RNTI. That is, since the legacy type terminal blindly decodes DCI format 1_0 scrambled with SI-RNTI, it can receive DCI format 1_0, but it may not receive DCI format X. Conversely, since the RedCap terminal blindly decodes DCI format X scrambled with a different value, it can receive DCI format X, but it may not receive DCI format 1_0. The RedCap terminal can further blindly decode DCI format 1_0 scrambled with SI-RNTI to receive DCI format 1_0, and receive SIB1 scheduled by DCI format 1_0.

[0250] As a third method, a legacy type terminal and a RedCap terminal can receive DCI format 1_0 and DCI format X, and DCI format 1_0 and DCI format X may be distinguished by a 1-bit indicator. The 1-bit indicator may be at the same position in DCI format 1_0 and DCI format X. If the value of the 1-bit is "0", it can be determined as DCI format 1_0, and if the value of the 1-bit is "1", it can be determined as DCI format X. Although it is described as 1 bit for convenience, it may be distinguished by multiple bits, or may be determined by a combination of specific code points.

[0251] II. RedCap terminal PRACH setting and RAR reception method

[0252] This embodiment relates to a method for receiving multiple PRACH settings and random access responses (RARs) according to multiple PRACH settings during an initial cell access and random access process of a terminal.

[0253] Generally, the UE may receive one PRACH configuration for an arbitrary access from the base station through the SIB. For reference, the system information block may configure one uplink initial BWP. Here, the uplink initial BWP is a BWP used by the UE in the arbitrary access process. The one uplink initial BWP includes one PRACH configuration.

[0254] The PRACH configuration may include at least one of the following information:

[0255] - Slots in which PRACH occasions are transmitted in the time domain

[0256] - the symbol in which the PRACH opportunity begins within the slot in which the PRACH opportunity is transmitted in the time domain

[0257] - the subcarrier in which the PRACH opportunity is located in the frequency domain

[0258] - the number of RACH opportunities, which is a set of PRACH opportunities in the frequency domain

[0259] - the sequence used by the preamble in the code area

[0260] Here, one PRACH opportunity may be configured with a maximum of 64 preambles, and each preamble may be assigned an index value of 0, 1, . . . , 63.

[0261] The base station may configure an additional uplink carrier to provide higher coverage to the terminal. This is called a supplementary UL carrier (SUL carrier). The base station may also configure a PRACH in the SUL, and the terminal may connect to an uplink cell using the PRACH of the SUL. For reference, the SIB may configure one uplink initial BWP in the SUL. Here, the uplink initial BWP is a BWP used by the terminal in an optional access process. The one uplink initial BWP may include one PRACH configuration.

[0262] Thereafter, in order to distinguish between SUL and normal uplink carriers in the present invention, the normal uplink carrier is called a normal UL carrier (NUL carrier). Unless otherwise specified, the embodiments disclosed in the present invention may be applied without distinguishing between NUL / SUL.

[0263] If the UE receives both the PRACH configuration on the NUL carrier and the PRACH configuration on the SUL carrier, the UE can perform a random access using the PRACH of the NUL carrier and a random access using the PRACH of the SUL carrier. That is, the UE can perform a random access process by transmitting one of the PRACH of the NUL carrier and the PRACH of the SUL carrier to the base station.

[0264] The terminal can select one preamble based on the PRACH information and transmit the selected preamble to the base station. The outline of the subsequent optional access process is as follows.

[0265] The terminal may transmit a preamble and monitor a PDCCH transmitted from the base station for a certain period of time. Here, the terminal may monitor a PDCCH scrambled with RA-RNTI. Here, the value of RA-RNTI is a value determined by a preamble transmitted by the terminal, and a specific method of obtaining a value of RA-RNTI will be described later. When the terminal receives a PDCCH scrambled with RA-RNTI, the terminal may receive a PDSCH scheduled by the PDCCH. The PDSCH may include information for scheduling a message 3 (massage 3) PUSCH and a TC-RNTI value. The terminal may transmit a message 3 PUSCH to the base station according to the scheduling information. Then, the terminal may receive a PDCCH for scheduling a message 4 (massage 4) PDSCH from the base station. Here, the PDCCH may be scrambled with a TC-RNTI value. When the terminal receives a PDCCH scrambled with a TC-RNTI value, the terminal can receive a message 4 PDSCH scheduled by the PDCCH, and can transmit a HARQ-ACK to the base station depending on the success or failure of the PDSCH.

[0266] The method in which the UE obtains the RA-RNTI in the above-mentioned optional access process is as follows.

[0267] [Number 1]

[0268]

number

[0269] where s_id is the index of the first OFDM symbol of the PRACH opportunity (0≦s_id<14), t_id is the index of the first slot of the PRACH opportunity in the system frame (0≦t_id<80), f_id is the index of the PRACH opportunity 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 carrier and 1 for SUL carrier).

[0270] The terminal and the base station can obtain the RA-RNTI according to Equation 1. If two terminals transmit preambles at different PRACH opportunities, at least one of s_id, t_id, and f_id for each terminal is different. Therefore, two terminals that transmit preambles at different PRACH opportunities monitor PDCCHs scrambled with different RA-RNTIs, so that it is possible to distinguish the preamble and the PDCCHs accordingly. In addition, even if different terminals have the same s_id, t_id, and f_id, if one terminal transmits a preamble at a NUL carrier and the other terminal transmits a preamble at a SUL carrier, the two terminals can monitor PDCCHs scrambled with different RA-RNTIs according to the ul_carrier_id value. Therefore, the preambles of the two terminals and the PDCCHs accordingly can be distinguished.

[0271] The RA-RNTI values ​​of two terminals are the same when they transmit preambles in PRACH opportunities with the same s_id, t_id, and f_id on the same carrier (one of NUL and SUL). In this case, if the preambles transmitted by the two terminals in the PRACH opportunity are different from each other, the preambles can be distinguished by the ID of the preamble. More specifically, since the two terminals have the same RA-RNTI value, they monitor the PDCCH scrambled with the same RA-RNTI value. If the two terminals receive the PDCCH scrambled with the RA-RNTI value, they can receive the PDSCH scheduled by the PDCCH. Here, the PDSCH can include a random access preamble identifier (RAPID). If the RAPID is the same as the index of the preamble transmitted by the terminal, the terminal can know that the RAR is a random access response corresponding to the preamble transmitted by the terminal. Therefore, two terminals transmitting different preambles can be distinguished by the RAPID.

[0272] In this way, each terminal can receive the RAR transmitted to itself based on the PRACH opportunity and preamble index of the PRACH transmitted by itself. However, there may be a case where the RAR transmitted to itself cannot be determined based on the PRACH opportunity and preamble index of the PRACH transmitted by the terminal. In the following, an embodiment to solve such a problem is disclosed.

[0273] The base station may further configure a new PRACH configuration for the RedCap terminal to support a new type of terminal such as the RedCap terminal. Hereinafter, for convenience, the PRACH configuration for the legacy type terminal is referred to as a legacy PRACH configuration, and the PRACH configuration newly configured for the RedCap terminal is referred to as a new PRACH configuration. The reason or motivation for the base station to provide the new PRACH configuration to the RedCap terminal is as follows.

[0274] - Reason 1: The base station can perform different scheduling methods during the optional access process depending on the type of the terminal. For example, the base station can repeatedly transmit a PDSCH including an RAR and a message 4 PDSCH including a message 4 to increase the downlink coverage of the RedCap terminal. Also, the base station can instruct the RedCap terminal to repeatedly transmit a message 3 PUSCH including a message 3 to increase the uplink coverage of the RedCap terminal. Thus, the base station must know the type of the terminal in order to schedule for the RedCap terminal. This is possible by the RedCap terminal transmitting a PRACH through a separate new PRACH configuration.

[0275] - Reason 2: The base station can use different PRACH formats depending on the type of terminal. For example, to increase the uplink coverage of a RedCap terminal, a PRACH format with high coverage can be used, and a PRACH format with low coverage can be used for general terminals. To this end, a new PRACH setting can be provided separately for the RedCap terminal.

[0276] - Reason 3: The number of RedCap terminals is generally greater than the number of general terminals. Therefore, when general terminals and RedCap terminals perform random connection using the same PRACH setting, the random connection attempts of many RedCap terminals make it difficult for a small number of general terminals to randomly connect. Therefore, in order to ensure successful random connection of general terminals, the random connection of RedCap terminals and the random connection of general terminals need to be separated. This can be done by providing a separate new PRACH setting to the RedCap terminal.

[0277] - Reason 4: The RedCap terminal has an application that transmits data periodically. For example, in the case of a wireless sensor, measured data is transmitted at regular intervals. Therefore, the terminal is likely to periodically attempt an optional connection. The base station can reduce the PRACH overhead by configuring the PRACH according to the characteristics of the RedCap terminal. To this end, the base station may provide the RedCap terminal with a new PRACH configuration.

[0278] The following describes a method in which a base station provides a new PRACH setting to a RedCap terminal.

[0279] 22A and 22B are diagrams illustrating PRACH resource configuration according to still another embodiment of the present invention, in which (a) is a diagram illustrating a first method thereof, and (b) is a diagram illustrating a second method thereof.

[0280] According to the first method, the RedCap terminal can receive the new PRACH configuration through the SIB transmitted from the base station.

[0281] More specifically, the SIB may configure one uplink initial BWP in one uplink cell (NUL or SUL). Here, the uplink initial BWP is a BWP used by the UE in an optional access process and may be referred to as an initial uplink BWP. The one uplink initial BWP may include an existing legacy PRACH configuration and a new PRACH configuration. For reference, the number of new PRACH configurations may be one or more. For convenience, when there are multiple new PRACH configurations, an index may be added to distinguish each new PRACH configuration. For convenience, the index may start from 0.

[0282] According to the second method, the RedCap UE may be configured with a plurality of uplink initial BWPs by the SIB transmitted from the base station. Here, each uplink initial BWP may include a PRACH configuration. More specifically, the SIB may configure an existing uplink initial BWP and a new uplink initial BWP in one uplink cell (NUL or SUL). Here, each uplink initial BWP may include one PRACH configuration. Specifically, the existing uplink initial BWP may include a legacy PRACH configuration, and the new uplink initial BWP may include a new PRACH configuration. The UE may select one of the plurality of uplink initial BWPs to transmit a PRACH. At this time, the selected uplink initial BWP is a BWP used by the UE in an optional access process. For reference, the number of new uplink initial BWPs may be one or more. For convenience, when there are a plurality of new uplink initial BWPs, an index may be added to distinguish the new PRACH configuration of each new uplink initial BWP. For convenience, the index may start at zero.

[0283] According to the first or second method, the RedCap terminal may be provided with one or more new PRACH configurations, where the RedCap terminal may perform an optional connection according to one of the new PRACH configurations.

[0284] Assume that the base station provides a legacy PRACH configuration and one new PRACH configuration to the terminal. One of the two terminals can transmit a preamble according to the legacy PRACH configuration, and the other terminal can transmit a preamble according to the new PRACH configuration. The preambles transmitted by the two terminals according to the legacy PRACH configuration and the new PRACH configuration may differ in at least one of time, frequency, and code, so that the base station can distinguish the preambles transmitted by the two terminals. Therefore, the base station must transmit an RAR for optional connection to each of the two terminals.

[0285] As described above, a terminal can determine which RAR it should receive by using the RA-RNTI corresponding to its own preamble or the index of the preamble. However, when one terminal transmits a preamble by a legacy PRACH configuration and another terminal transmits a preamble by a new PRACH configuration, the two terminals cannot determine which RAR they should receive in the following situation.

[0286] For example, if the s_id, t_id, and f_id of a preamble selected by one terminal's legacy PRACH configuration are the same as the s_id, t_id, and f_id of a preamble selected by another terminal's new PRACH configuration, the two terminals monitor the PDCCH that schedules the RAR based on the same RA-RNTI value. At this time, if the index of a preamble selected by one terminal's legacy PRACH configuration is the same as the index of a preamble selected by another terminal's new PRACH configuration, the two terminals determine the RAR with the same RAPID. Therefore, the two terminals determine the RAR as their own RAR, and therefore have the same message 3 PUSCH scheduling grant and TC-RNTI value.

[0287] As described above, a problem may occur when the base station provides a new PRACH configuration, and a method for solving the problem will be disclosed below.

[0288] According to the first method, the RA-RNTI value may be determined according to which PRACH configuration preamble is transmitted. If the terminal transmits a preamble of a legacy PRACH configuration, the terminal can determine the RA-RNTI value as follows.

[0289] [Number 2]

[0290]

number

[0291] where s_id is the index of the first OFDM symbol of the PRACH opportunity (0≦s_id<14), t_id is the index of the first slot of the PRACH opportunity in the system frame (0≦t_id<80), f_id is the index of the PRACH opportunity 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 carrier and 1 for SUL carrier).

[0292] In order to reduce the latency in the optional access procedure using the legacy PRACH setting, the terminal can perform a simplified optional access procedure using the new PRACH setting. This procedure is called a two-step optional access procedure. For convenience, the PRACH setting in the two-step optional access procedure is called a two-step PRACH. The two-step optional access procedure is outlined as follows.

[0293] The terminal may transmit one preamble and data selected using PRACH information set for the two-step arbitrary access process to the base station. Then, the terminal may monitor the PDCCH transmitted from the base station for a certain period of time. Here, the terminal may monitor the PDCCH scrambled with MsgB-RNTI. Here, the value of MsgB-RNTI is a value determined by the preamble transmitted by the terminal, and a specific method of obtaining the value of MsgB-RNTI will be described later. When the terminal receives the PDCCH scrambled with MsgB-RNTI, the terminal may receive the PDSCH scheduled by the PDCCH, and may transmit a HARQ-ACK to the base station depending on whether the PDSCH is received or not.

[0294] The above-mentioned MsgB-RNTI can be interpreted as the RA-RNTI of a terminal performing a two-step arbitrary access process. Therefore, if the index of a preamble selected by one terminal through the two-step PRACH configuration is the same as the index of a preamble selected by another terminal through a new PRACH configuration, the two terminals determine the RAR in the same RAPID, which causes a problem that the terminal cannot determine the RAR that it should receive.

[0295] If the terminal transmits a preamble for two-step PRACH configuration, the terminal can determine the MsgB-RNTI value as follows.

[0296] [Number 3]

[0297]

number

[0298] where s_id is the index of the first OFDM symbol of the PRACH opportunity (0≦s_id<14), t_id is the index of the first slot of the PRACH opportunity in the system frame (0≦t_id<80), f_id is the index of the PRACH opportunity 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 carrier and 1 for SUL carrier).

[0299] In one aspect, if the terminal transmits a preamble for a new PRACH configuration, the terminal may determine the RA-RNTI value as follows.

[0300] [Number 4]

[0301]

number

[0302] Here, the new PRACH configuration index is an index assigned to each new PRACH configuration and may start from 0. Here, X may be determined based on the maximum value that can be obtained by Equation 2 for determining the RA-RNTI. If s_id=13, t_id=79, f_id=7, and ul_carrier_id=1 are possible, X may be determined to be 17920, which is the maximum value that can be obtained by Equation 2.

[0303] The RA-RNTI obtained in this example has the following characteristics.

[0304] When the terminal transmits a preamble for a legacy PRACH configuration, the value of RA-RNTI has one value between 1 and X=17920 according to Equation 2. When the terminal transmits a preamble for a new PRACH configuration, the value of RA-RNTI has a value equal to or greater than X+1 according to Equation 4. Therefore, the terminal that transmits a preamble for a legacy PRACH configuration and the terminal that transmits a preamble for a new PRACH configuration can monitor the PDCCH with different RA-RNTI values. Therefore, the base station can schedule different RARs for the two terminals using the different RA-RNTIs.

[0305] In another aspect, the mathematical formula for determining the RA-RNTI may be expressed as follows:

[0306] [Number 5]

[0307]

number

[0308] Here, the contents indicated by the ID are as follows:

[0309] - Legacy PRACH in ID=0:NUL carrier

[0310] - ID=1: Legacy PRACH in SUL carrier

[0311] - ID=2: New PRACH with the first index

[0312] - ID=3: New PRACH with the second index

[0313] - ID=...

[0314] In this example, when multiple new PRACH configurations are provided, the maximum number of new PRACH configurations is 5. That is, the index of the new PRACH is one of values ​​0, 1, 2, 3, and 4. For reference, the first index is the first lowest index, and the second index is the second lowest index. Here, the index may be uniquely assigned to each new PRACH. The index may be set by a higher layer signal (or an RRC signal) that selects each new PRACH, or may be derived by the configuration of each new PRACH. The index may be derived based on at least one of time and frequency information of the configuration of the new PRACH.

[0315] In yet another aspect, when the terminal transmits a preamble for a new PRACH configuration, the terminal may determine the RA-RNTI value as follows.

[0316] [Number 6]

[0317]

number

[0318] Here, the new PRACH configuration index is an index assigned to each new PRACH configuration and may start from 0. Here, X may be determined by the maximum value that can be obtained by Equation 3 for determining the RA-RNTI. If s_id=13, t_id=79, f_id=7, and ul_carrier_id=1 are possible, X may be determined as 35840 by Equation 3.

[0319] The RA-RNTI obtained in this example has the following characteristics.

[0320] When the terminal transmits a preamble for a new PRACH configuration, the value of RA-RNTI has one of values ​​from 1 to X=35840 according to Equation 3. When the terminal transmits a preamble for a new PRACH configuration, the value of RA-RNTI has a value equal to or greater than X+1 according to Equation 6. Therefore, the terminal that transmits a preamble for an existing PRACH configuration and the terminal that transmits a preamble for a new PRACH configuration can monitor the PDCCH with different RA-RNTI values. Therefore, the base station can schedule different RARs for the two terminals using the different RA-RNTIs.

[0321] In yet another aspect, the mathematical formula for determining the RA-RNTI may be expressed as follows:

[0322] [Number 7]

[0323]

number

[0324] Here, the contents indicated by the ID are as follows:

[0325] - Legacy PRACH in ID=0:NUL carrier

[0326] - ID=1: Legacy PRACH in SUL carrier

[0327] - ID=2: 2-step PRACH in NUL carrier

[0328] - ID=3: 2-step PRACH in SUL carrier

[0329] - ID=4: New PRACH with the first index

[0330] - ID=5: New PRACH with the second index

[0331] In the embodiment, when multiple new PRACH configurations are provided, the maximum number of new PRACH configurations is 2. That is, the index of the new PRACH is one of values ​​0 and 1. For reference, the first index is the first index, and the second index is the second lowest index. Here, the index may be uniquely assigned to each new PRACH. The index may be set by a higher layer signal (or an RRC signal) that selects each new PRACH, or may be derived by the configuration of each new PRACH. The index may be derived based on at least one of time and frequency information of the configuration of the new PRACH.

[0332] For reference, the RedCap terminal may be configured to use a method of calculating the RA-RNTI from the SIB. For example, the RedCap terminal may be configured to use one of the mathematical formulas 4 or 6 (or 5 or 7) according to the SIB. As another example, the RedCap terminal may be configured to use one of the mathematical formulas 4 or 6 (or 5 or 7) according to the two-step RACH configuration even if there is no separate instruction in the SIB. For example, if the two-step RACH is configured, the RA-RNTI value may be calculated using the mathematical formula 6 (or 7), and if not, the RA-RNTI value may be calculated using the mathematical formula 4 (or 5). Furthermore, only if the two-step RACH is configured and the PRACH resource of the two-step RACH overlaps with the PRACH resource of the RedCap terminal, the RA-RNTI value may be calculated using the mathematical formula 6 (or 7), and if not, the RA-RNTI value may be calculated using the mathematical formula 4 (or 5).

[0333] According to the second method, a search space for monitoring the PDCCH may be determined differently depending on what PRACH-configured preamble is transmitted. If the terminal transmits a preamble of the legacy PRACH configuration, the terminal may monitor the PDCCH based on the RA-RNTI value in the first search space to receive the RAR. If the terminal transmits a preamble of the new PRACH configuration, the terminal may monitor the PDCCH based on the RA-RNTI value in the second search space to receive the RAR. Here, the RA-RNTI value may be determined based on Equation 1 for determining the RA-RNTI. That is, different terminals may monitor the PDCCH with the same RA-RNTI value, but may receive the RAR corresponding to the preamble transmitted by the terminal by monitoring the PDCCH in different search spaces.

[0334] More specifically, the terminal may be signaled as follows: The terminal may receive a new PRACH configuration for an arbitrary connection and a search space configuration corresponding to the new PRACH configuration using the SIB transmitted from the base station. Here, the search space configuration allows the terminal to know the following information.

[0335] - A slot in which the search space is set by information about the period and offset

[0336] - the number of consecutive slots over which the search space is set

[0337] - the symbol in the slot where the search space begins

[0338] - The PDCCH aggregation level (AL) to be monitored in the search space and the number of PDCCH candidates per AL

[0339] - DCI formats to monitor in the search space

[0340] The search space corresponding to the new PRACH configuration may be associated with CORESET#0. Thus, the search space corresponding to the preamble of the legacy PRACH configuration and the search space corresponding to the preamble of the new PRACH configuration may be associated with the same CORESET#0, and therefore may have the same frequency domain information, CCE-to-REG mapping, and CORESET duration.

[0341] If a separate search space corresponding to the new PRACH is not set, the UE may monitor the PDCCH for RAR reception in the search space corresponding to the legacy PRACH. In this case, the RA-RNTI value when monitoring the PDCCH may be based on Equation 1 for determining the RA-RNTI or the equation for determining the RA-RNTI proposed in the first method.

[0342] According to the third method, the CORESET for monitoring the PDCCH may be determined differently depending on what PRACH configuration preamble the terminal transmits. If the terminal transmits a preamble of the legacy PRACH configuration, the terminal may monitor the PDCCH based on the RA-RNTI value in the search space of the first CORESET to receive the RAR. If the terminal transmits a preamble of the new PRACH configuration, the terminal may 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 may be determined based on Equation 1 for determining the RA-RNTI. That is, the terminal monitors the PDCCH with the same RA-RNTI value, but monitors the PDCCH in the search space of different CORESETs, thereby receiving the RAR corresponding to the preamble transmitted by the terminal.

[0343] More specifically, the terminal may be signaled as follows: The terminal may receive a new PRACH configuration for an arbitrary connection and a CORESET configuration corresponding to the new PRACH configuration using the SIB transmitted from the base station. Here, the terminal can know the following information from the CORESET configuration.

[0344] - Frequency information where the CORESET is located, which is known from a set of 6 consecutive PRBs.

[0345] - Mapping between REGs and CCEs included in the CORESET, which may be one of a localized mapping and a distributed mapping.

[0346] - The number of symbols contained in the CORESET. This can be 1 symbol, or 2 or 3 consecutive symbols.

[0347] According to the fourth method, a downlink initial BWP for performing an optional connection may be determined differently depending on what PRACH configuration preamble the terminal transmits. If the terminal transmits a preamble for a legacy PRACH configuration, the terminal may monitor a PDCCH based on an RA-RNTI value in a first downlink initial BWP to receive an RAR. If the terminal transmits a preamble for a new PRACH configuration, the terminal may monitor a PDCCH based on an RA-RNTI value in a second downlink initial BWP to receive an RAR. Here, the RA-RNTI value may be determined based on Equation 1 for determining RA-RNTI. In each downlink initial BWP, a CORESET and a search space for monitoring the PDCCH may be set. That is, the terminal monitors a PDCCH with the same RA-RNTI value, but monitors the PDCCH with different downlink initial BWPs to receive an RAR corresponding to the preamble transmitted by the terminal.

[0348] III. RedCap Terminal Frequency Hopping Method

[0349] FIG. 23 is a diagram showing scheduling of the Physical Uplink Shared Channel in the time domain, and FIG. 24 is a diagram showing scheduling of the Physical Uplink Shared Channel in the frequency domain.

[0350] A method for a terminal to transmit a physical uplink shared channel (PUSCH) will be described with reference to FIG. 23 or FIG. 24.

[0351] The terminal can transmit uplink data on the physical uplink shared channel by a method of scheduling transmission of the physical uplink shared channel in downlink control information (DCI) transmitted over a physical downlink control channel (PDCCH) (DG, dynamic grant) or a method of transmitting the physical uplink shared channel according to a resource and transmission method preconfigured in the base station (CG, configured grant).

[0352] Downlink control information (DCI) received by the terminal via the PDCCH may include scheduling information of the PUSCH. The scheduling information may include information on the time domain (TDRA, time-domain resource assignment) and information on the frequency domain (FDRA, frequency-domain resource assignment). The terminal may interpret the DCI received via the PDCCH based on information on a control resource set and a search space, and perform an operation indicated by the DCI. The DCI may include one of DCI formats 0_0, 0_1, or 0_2 for scheduling a physical uplink shared channel (PUSCH).

[0353] 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 an offset value between the slot in which the PDCCH is received from the base station and the slot in which the terminal transmits the PUSCH. SLIV (Start and length indication value) is a value obtained by jointly coding the start symbol index (S) of the PUSCH and the symbol length (L) of the PUSCH in the slot indicated by K2.

[0354] When the terminal receives DCI format 0_0, 0_1, or 0_2 for scheduling the PUSCH in slot n, the terminal μPUSCH / n*2 μPDCCH )+K2 slots, where μPUSCH and μPDCCH are the subcarrier spacing (SCS) of the cell where PUSCH is scheduled and the cell where PDCCH is received, respectively.

[0355] For example, referring to FIG. 23(a), since the subcarrier spacing of the cell that receives the PDCCH and the cell in which the PUSCH is scheduled is the same, when the terminal receives the PDCCH in slot n and, for example, the K2 value is indicated as 4, the terminal determines that the slot in which the PUSCH is scheduled is slot n+K2=n+4.

[0356] The physical uplink shared channel transmitted by the terminal can apply two mapping types, A and B. The SLIV, in which the starting symbol index and the symbol length of the PUSCH are jointly encoded, has different ranges of values ​​that can be taken depending on the PUSCH mapping type. The PUSCH mapping type A allows only resource allocation including a DMRS symbol, and the DMRS symbol is located at the third or fourth OFDM symbol of the slot depending on a value specified by a higher layer. That is, in the case of the PUSCH mapping type A, the index (S) of the starting symbol of the PUSCH is 0, and the length (L) of the PUSCH can have one of values ​​from 4 to 14 (12 in the extended CP) depending on the DMRS symbol position. In the case of the PUSCH mapping type B, the DMRS symbol is always the first symbol of the PUSCH, so that S can have one of values ​​from 0 to 13 (11 in the extended CP) and L can have one of values ​​from 1 to 14 (12 in the extended CP). Also, one PUSCH cannot cross a slot boundary, so the values ​​of S and L should satisfy S+L14 (12 for extended CP).

[0357] Figure 23 (b) shows an example of PUSCH according to PUSCH mapping type. From the top to bottom, the terminal determines that a mapping type A PUSCH in which the third symbol is a DMRS symbol, the start symbol index (S) is 0, and the length (L) is 7, a mapping type A PUSCH in which the fourth symbol is a DMRS symbol, the start symbol index (S) is 0, and the length (L) is 7, and a mapping type B PUSCH in which the first symbol is a DMRS symbol, the start symbol index (S) is 5, and the length (L) is 5 are scheduled. The frequency domain information of the PUSCH indicated by the FDRA field in the DCI format 0_0, 0_1, or 0_2 can be divided into two types according to the frequency resource allocation type.

[0358] The first type is frequency resource allocation type 0, in which a fixed number of PRBs are grouped together according to the number of RBs included in the BWP configured in the terminal to create a resource block group (RBG), and the terminal is instructed on a bitmap in units of RBGs to determine whether to use the RBGs. The number of PRBs included in one RBG is configured in a higher layer, and the larger the number of RBs included in the BWP configured in the terminal, the greater the number of PRBs configured. For example, referring to FIG. 24(a), when the BWP size configured in the terminal is 72 PRBs and 1 RBG is composed of 4 PRBs, the terminal determines 4 PRBs in ascending order starting from PRB0 as 1 RBG. That is, when PRB0 to PRB3 are mapped to RBG0, and PRB4 to PRB7 are mapped to RBG17 in the order of RBG17, a total of 18 bits, 1 bit (0 or 1) for each RBG, are received to determine whether to use the PRBs in the RBG. In this case, if the bit value is 0, it is determined that the PUSCH is not scheduled for any PRB in the RBG, and if the bit value is 1, it is determined that the PUSCH is scheduled for all PRBs in the RBG. Alternatively, the bit value may be applied inversely.

[0359] The second type is frequency resource allocation type 1, which can indicate information on consecutive PRBs allocated according to the size of the initial BWP or active BWP of the terminal. This information is a resource indication value (RIV) in which the start index (S) and length (L) of consecutive PRBs are jointly encoded. For example, referring to FIG. 24(b), when the BWP size of the terminal is 50 PRBs and PUSCH is scheduled from PRB2 to PRB11, the start index of consecutive PRBs is 2 and the length is 10. The terminal can use RIV=N size BWP By receiving *(L-1)+S=50*(10-1)+2=452, the starting index and length of consecutive PRBs for which PUSCH is scheduled can be determined to be 2 and 10, respectively.

[0360] Only in DCI format 0_1 ​​or 0_2 for scheduling PUSCH, the terminal may be configured by a higher layer to use only one of the two frequency resource allocation types for PUSCH or to dynamically use the two types. When configured to dynamically use the two types, the terminal can determine which type is the most significant bit (MSB) of the FDRA field in DCI format 0_1 ​​or 0_2 for scheduling PUSCH.

[0361] In order to support uplink URLLC transmission, etc., a configured grant-based uplink shared channel transmission method is supported, and this method is called grant-free transmission. The configured grant-based uplink transmission method is a method in which, when a base station configures resources available for uplink transmission to a terminal in a higher layer, i.e., RRC signaling, the terminal transmits an uplink shared channel using the resources. This method can be divided into two types depending on whether it can be activated or deactivated using DCI.

[0362] The type 1 configured grant-based transmission method is a method of setting resources and a transmission method for grant-based transmission that are pre-configured in a higher layer.

[0363] The type 2 configured grant-based transmission scheme is a scheme in which grant-based transmission configured by a higher layer is set, and the resources and scheme for transmission are indicated by DCI conveyed via the physical downlink control channel.

[0364] The configured grant-based uplink transmission scheme can support URLLC transmission, and therefore supports repeated transmission in multiple slots to ensure high reliability. In this case, one of {0,0,0,0}, {0,2,3,1}, and {0,3,0,3} is set as the RV (redundancy version) sequence, and an RV corresponding to the mod(n-1,4)+1th value is used in the n-th repeated transmission. In addition, a terminal configured for repeated transmission can start repeated transmission only in a slot where the RV value corresponds to 0. However, when the RV sequence is {0,0,0,0} and repeated transmission is performed in 8 slots, repeated transmission cannot be started in the 8th slot. The terminal ends repeated transmission when the number of repeated transmissions set by the upper layer is reached or the period is exceeded, or when the terminal receives an UL grant having the same HARQ process ID. Here, the UL grant refers to DCI that schedules the PUSCH.

[0365] In a wireless communication system, in order to improve the reception and transmission reliability of a physical uplink shared channel between a base station and a terminal, the terminal may be configured to repeatedly transmit the uplink shared channel from the base station, which is illustrated in FIG.

[0366] FIG. 25 is a diagram illustrating repeated transmission of a physical uplink shared channel according to an example.

[0367] Referring to FIG. 25, PUSCH repetitive transmissions that a terminal can transmit can be divided into two types.

[0368] First, the transmission process of PUSCH repetitive transmission type A of the terminal is as follows. When the terminal receives DCI format 0_1 ​​or 0_2 from the base station via the PDCCH that schedules the PUSCH, the PUSCH can be repeatedly transmitted in only K consecutive slots. Here, the terminal may receive the K value set by a higher layer or added to the TDRA field of the DCI. For example, referring to FIG. 25(a), assuming that the terminal receives the PDCCH that schedules the PUSCH in slot n and receives a K2 value of 2 and a K value of 4 from the DCI format received in the PDCCH, the terminal starts transmitting the PUSCH in slot n+K2, i.e., n+2, and repeatedly transmits the PUSCH from slot n+2 to slot n+2+K-1, i.e., n+5. At this time, the time and frequency resources in which the PUSCH is transmitted in each slot are the same as those indicated by the DCI. That is, the PUSCH may be transmitted in the same symbol and PRB in a slot.

[0369] Next, a PUSCH repetition transmission type B transmission process for supporting low-latency PUSCH repetition transmission in order for the terminal to meet the requirements of URLLC is as follows. The base station may indicate the start symbol (S) of the PUSCH and the length (L) of the PUSCH to the terminal through the TDRA field. Here, the PUSCH obtained according to the indicated start symbol and length is not an actual PUSCH to be transmitted but a temporarily obtained PUSCH, and is called a nominal PUSCH. Also, the terminal may indicate the nominal repetition number (N) of the indicated nominal PUSCH through the TDRA field. The terminal may determine the nominal repetition number (N) of nominal PUSCH including the nominal PUSCH indicated in the TDRA field. Here, the nominal PUSCHs with the nominal repetition number (N) have the same length of L, and are continuous on the time axis since there is no additional symbol between the nominal PUSCHs.

[0370] The terminal may determine an actual PUSCH from the nominal PUSCH. One nominal PUSCH may be determined as one or a plurality of actual PUSCHs. A symbol that cannot be used in PUSCH repetitive transmission type B may be indicated or set to the terminal by the base station. This is called an invalid symbol. The terminal may exclude the invalid symbol from the nominal PUSCH. As described above, the nominal PUSCH is determined as consecutive symbols, but may be determined as discontinuous when invalid symbols are excluded. The actual PUSCH may be determined as consecutive symbols in one nominal PUSCH excluding invalid symbols. Here, if consecutive symbols cross a slot boundary, the actual PUSCH may be divided and determined based on the boundary.

[0371] For reference, the invalid symbols may include at least DL symbols configured by the base station to the terminal.

[0372] For example, referring to FIG. 25(b), assume that a 5-symbol long PUSCH transmission is scheduled for a terminal from the 12th OFDM symbol of the 1st slot (slot n) and 4 type B repetitions are instructed. 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 in slot n. Symbol k index starts from 0 to 13 in normal CP and goes from 0 to 11 in extended CP.

[0373] Assume that invalid symbols are set or indicated to symbols 6 and 7 of slot n+1. Due to the invalid symbols set 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.

[0374] The first nominal PUSCH (nominal#1) is divided into two actually transmitted (actual) PUSCHs (actual#1 and actual#2) by the slot boundary. The second nominal PUSCH (nominal#2) and the third nominal PUSCH (nominal#3) are each divided into one actually transmitted (actual) PUSCH (actual#3 and actual#4) by grouping consecutive symbols excluding invalid symbols. Finally, the fourth nominal PUSCH (nominal#4) is divided into two actually transmitted (actual) PUSCHs (actual#5 and actual#6) by the slot boundary. The terminal finally transmits the actually transmitted (actual) PUSCH.

[0375] One actual PUSCH must include at least one DMRS symbol, and when PUSCH repetition transmission type B is configured, an actual PUSCH whose total length is one symbol may be omitted without being transmitted, because an actual PUSCH whose total length is one symbol cannot transmit information other than DMRS.

[0376] To obtain diversity gain in the frequency domain, a terminal may be configured for frequency hopping.

[0377] In the case of PUSCH repetitive transmission type A, the terminal may be configured with one of intra-slot frequency hopping, which performs frequency hopping within a slot, and inter-slot frequency hopping, which performs frequency hopping for each slot. When intra-slot frequency hopping is configured in the terminal, the terminal divides the PUSCH in the slot in which the PUSCH is transmitted into two in the time domain, transmits one half with a scheduled PRB, and transmits the other half with a PRB obtained by adding an offset value to the scheduled PRB. In this case, two or four values ​​of the offset value are configured in the higher layer according to the active BWP size, and one of the values ​​may be indicated to the terminal by DCI. When inter-slot frequency hopping is configured in the terminal, the PUSCH is transmitted with a scheduled PRB in a slot with an even slot index, and the PUSCH is transmitted with a PRB obtained by adding an offset value to the scheduled PRB in an odd slot.

[0378] In the case of PUSCH repetition transmission type B, the frequency hopping may be set to one of inter-repetition frequency hopping, which performs frequency hopping at a nominal PUSCH boundary, and inter-slot frequency hopping, which performs frequency hopping every slot. When inter-repetition frequency hopping is set in the terminal, the terminal transmits an actual PUSCH corresponding to an odd-numbered nominal PUSCH in a scheduled PRB, and transmits an actual PUSCH corresponding to an even-numbered nominal PUSCH in a PRB obtained by adding an offset value to the scheduled PRB. In this case, the offset value may be set to two or four values ​​according to an active BWP size in a higher layer, and one of the values ​​may be indicated to the terminal by DCI. When inter-slot frequency hopping is configured in a terminal, the actual PUSCHs in slots with even slot indices are transmitted on the scheduled PRBs, and the actual PUSCHs in odd slots are transmitted on PRBs that are the scheduled PRBs plus an offset value.

[0379] When a terminal repeatedly transmits a PUSCH, if a symbol scheduled for transmitting a PUSCH in a particular slot overlaps with a semi-statically configured DL symbol or a symbol position set for receiving an SS / PBCH block, the terminal does not transmit the overlapping PUSCH in that slot and does not postpone transmission to the next slot.

[0380] Hereinafter, a method in which the terminal transmits the physical uplink control channel (PUCCH) will be described with reference to FIG.

[0381] FIG. 26 is a diagram showing scheduling of the physical uplink control channel.

[0382] Referring to FIG. 26, when a terminal receives DCI format 1_0, 1_1, or 1_2 for scheduling a physical uplink control channel, the terminal must transmit 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 may be HARQ-ACK information for reception success or failure of two types of channels. As a first type, when a physical downlink shared channel (PDSCH) is scheduled in the DCI format 1_0, 1_1, or 1_2, it may be HARQ-ACK for reception success or failure of the physical downlink shared channel (PDSCH). As a second type, when the DCI format 1_0, 1_1, or 1_2 is a DCI instructing the release of a semi-static physical downlink shared channel (SPS PDSCH), the second type may be a HARQ-ACK for the success or failure of reception of the DCI format 1_0, 1_1, or 1_2.

[0383] In order to transmit a PUCCH carrying a HARQ-ACK, the PDSCH-to-HARQ_Feedback timing indicator field included in the DCI format 1_0, 1_1, or 1_2 may indicate a K1 value, which is a value for information of a slot in which a scheduled uplink control channel should be transmitted. Here, the K1 value may be a non-negative integer value. The K1 value of DCI format 1_0 may indicate one of {0, 1, 2, 3, 4, 5, 6, 7}. The K1 value that can be indicated in DCI format 1_1 or 1_2 may be configured or set by a higher layer.

[0384] The terminal may determine a slot for transmitting an uplink control channel including the first type of HARQ-ACK information as follows. The terminal may determine an uplink slot overlapping with a last symbol of a physical downlink shared channel (PDSCH) corresponding to the HARQ-ACK information. If an index of the uplink slot is m, the uplink slot in which the terminal transmits the physical uplink control channel including the HARQ-ACK information may be m+K1. Here, the index of the uplink slot is a value according to a subcarrier spacing of an uplink BWP in which the uplink control channel is transmitted.

[0385] For reference, when downlink slot aggregation is configured in the terminal, the ending symbol indicates the last symbol of a physical downlink shared channel (PDSCH) scheduled in the last slot among slots in which the PDSCH is received.

[0386] Referring to Figure 26, let us assume that the subcarrier spacing of the DL BWP in which the PDCCH is received, the subcarrier spacing of the DL BWP in which the PDSCH is scheduled, and the subcarrier spacing of the UL BWP in which the PUCCH is transmitted are the same. Let us assume that the UE receives the PDCCH scheduling the PDSCH and PUCCH from the base station in slot n, and that K0 = 2 and K1 = 3 indicated in the DCI transmitted by the PDCCH. When the reception of the last symbol of the PDSCH ends in slot n + K0, i.e., n + 2, the UE must transmit the HARQ-ACK of the PDSCH via the PUCCH in slot n + 2 + K1, i.e., n + 5.

[0387] To ensure wide coverage in the NR system, a terminal may be configured to repeatedly transmit a long PUCCH (PUCCH format 1, 3, 4) in 2, 4, or 8 slots. When a terminal is configured to repeatedly transmit a PUCCH, the same UCI is repeatedly transmitted in every slot. This will be described with reference to FIG. 27.

[0388] FIG. 27 is a diagram illustrating repeated transmission of the physical uplink control channel.

[0389] 27, when the reception of the PDSCH ends in slot n and K1=2, the terminal transmits the PUCCH in slot n+K1, i.e., n+2. At this time, the number of repetitive transmissions for the PUCCH is N. repeat PUCCH = 4, the PUCCH is repeatedly transmitted from slot n+2 to slot n+5. The symbol structure of the repeatedly transmitted PUCCH is the same, i.e., the repeatedly transmitted PUCCH starts from the same symbol in each slot and consists of the same number of symbols.

[0390] In order to obtain diversity gain in the frequency domain, frequency hopping may be configured in the terminal. For frequency hopping, intra-slot frequency hopping in which frequency hopping is performed within a slot and inter-slot frequency hopping in which frequency hopping is performed for each slot may be configured. When intra-slot frequency hopping is configured in the terminal, the terminal divides the PUCCH in half in the time domain in the slot in which the PUCCH is transmitted, transmits one half using a first PRB, and transmits the other half using a scheduled second PRB. In this case, the first PRB and the second PRB may be configured in the terminal by a higher layer that configures PUCCH resources. When inter-slot frequency hopping is configured in the terminal, the PUCCH is transmitted using the first PRB in slots with even slot indexes, and the PUCCH is transmitted using the second PRB in slots with odd slot indexes.

[0391] When a terminal repeatedly transmits a PUCCH, if the symbol at which the PUCCH must be transmitted in a particular slot overlaps with a semi-statically configured DL symbol or a symbol position set for receiving an SS / PBCH block, the terminal does not transmit the PUCCH in that slot and postpones transmission to the next slot, and transmits the PUCCH if the PUCCH symbol does not overlap with the symbol position set for receiving a semi-statically configured DL symbol or an SS / PBCH block in that slot.

[0392] When transmitting PUSCH or PUCCH, the terminal may transmit using a frequency hopping scheme to obtain frequency diversity gain. Here, the frequency hopping scheme refers to transmitting PUSCH or PUCCH in the 0th PRB set and transmitting PUSCH or PUCCH in the 1st PRB set. For reference, in the description of the present invention, PUSCH or PUCCH transmitted in the 0th PRB set is called hop 0 (hop0), and PUSCH or PUCCH transmitted in the 1st PRB set is called hop 1 (hop1). Although only a maximum of two hops (hop0 and hop1) are described in the present invention, the number of hops may be increased.

[0393] When a terminal transmits a PUSCH or a PUCCH, the method of determining the 0th PRB set of hop 0 and the 1st PRB set of hop 1 is as follows.

[0394] The PUCCH before RRC connection can be determined as follows: For reference, the PUCCH before RRC connection is a PUCCH that transmits a HARQ-ACK, which is a successful reception response of the PDSCH including Msg4.

[0395] The terminal selects one PUCCH resource from 16 PUCCH resources. In this case, the selection is based on a PUCCH resource indicator included in a DCI format for scheduling a PUCCH or an index of a control channel element (CCE) in which the DCI format is received. The index of the selected PUCCH resource is PUCCH Then it can have one of the values ​​0, 1, ..., 15.

[0396] Suppose r PUCCH If is a value of 0, 1, ..., 7, the index of the 0th PRB set of hop 0 of the selected PUCCH resource is

[0397]

number

[0398] and the index of the first PRB set at hop 1 is

[0399]

number

[0400] If r PUCCH If is a value of 8, 9, ..., 15, the index of the 0th PRB set of hop 0 of the selected PUCCH resource is

[0401]

number

[0402] and the index of the first PRB set at hop 1 is

[0403]

number

[0404] It is.

[0405] Here, N size BWP N is the number of PRBs included in the active BWP that transmits the PUCCH. Here, when the PUCCH transmits the HARQ-ACK of the Msg4PDSCH, the active BWP is the initial UL BWP. This initial UL BWP is the UL BWP for the UE to connect to a cell and is configured in SIB1 (system information block). CS is the number of initial cyclic shift indexes, and RB BWP offset and the initial cyclic shift index are as shown in Table 4.

[0406] [Table 4]

[0407] Here, if the index of the RB where the 0th PRB set of hop 0 starts is 0, it indicates the PRB with the lowest active BWP of the UE. For reference, when the PUCCH transmits the HARQ-ACK of the Msg4PDSCH, the active BWP is the initial UL BWP. That is, the index of the RB where the 0th PRB set of hop 0 starts is interpreted as the index of the initial UL BWP.

[0408] In the case of PUCCH after RRC connection, it can be determined as follows.

[0409] The lowest PRB index of the 0th PRB set of hop 0 of the PUCCH and the lowest PRB index of the 1st PRB set of hop 1 may be configured as PUCCH resources in the terminal by RRC signaling. That is, when one PUCCH resource is indicated, the terminal can transmit hop 0 and hop 1 using the lowest PRB index of the 0th PRB set of hop 0 and the lowest PRB index of the 1st PRB set of hop 1 configured in the PUCCH resource. Here, if the PRB index is 0, it indicates the lowest PRB of the active BWP of the terminal. That is, the PRB index is interpreted as the index of the active BWP of the terminal.

[0410] The PUSCH can be determined as follows.

[0411] The UE may determine the 0th PRB set for hop 0 using a DCI for scheduling a PUSCH or a DCI / RRC signal for activating a PUSCH. Here, the DCI for scheduling a PUSCH or the DCI / RRC signal for activating a PUSCH may include a frequency domain resource assignment (FDRA) field. The FDRA field may include an index of an RB where the 0th PRB set for hop 0 starts and the number of consecutive RBs. Here, if the index of an RB where the 0th PRB set for hop 0 starts is 0, it indicates the lowest PRB of the active BWP of the UE. That is, the index of an RB where the 0th PRB set for hop 0 starts is interpreted as the index of the active BWP of the UE. The UE must determine the index of an RB where the 1st PRB set for hop 1 starts. This can be determined by the following equation:

[0412]

number

[0413] Here, R.B. start (0) represents the index of the RB where the 0th PRB set of hop 0 starts, and RB start (1) represents the index of the RB where the first PRB set of hop 1 begins. offset represents the PRB interval between the 0th PRB set of hop 0 and the 1st PRB set of hop 1. The base station sends the RB offset The RB can be set and instructed. offset The values ​​of are 0, 1, ..., N BWP size N BWP sizerepresents the number of PRBs included in the active BWP of the terminal. If the index of the RB where the first PRB set of hop 1 starts, calculated by the above formula, is 0, it indicates the lowest PRB of the active BWP of the terminal. In other words, the index of the RB where the first PRB set of hop 1 starts (RB start (1)) is interpreted as an index of the terminal's active BWP.

[0414] When PUSCH transmits Msg3, RBoffset may have one of the following values: If the size of the initial UL BWP is less than 50 RBs, RB offset teeth,

[0415]

number

[0416] If the size of the initial UL BWP is greater than 50RB, the RB offset teeth

[0417]

number

[0418] Here, in the case of Msg3PUSCH, since the initial UL BWP is the active BWP, N BWP size is the number of RBs that the initial UL BWP contains.

[0419] In the above-mentioned frequency hopping scheme, the 0th PRB set of hop 0 (hop0) and the 1st PRB set of hop 1 (hop1) are located within the active BWP. For reference, in the case of PUSCH (i.e., Msg3PUSCH) and PUCCH (i.e., PUCCH transmitting HARQ-ACK of Msg4PDSCH) before RRC connection, the active BWP is the initial UL BWP. However, the UE may need to frequency hop in a frequency band other than the active BWP in the following situations.

[0420] As a first example, the bandwidth of the RF supported by the terminal is significantly smaller than the bandwidth supported by the cell (see FIG. 28 for example).

[0421] FIG. 28 is a diagram illustrating frequency hopping.

[0422] Referring to FIG. 28, assume that the UE's RF bandwidth supports up to 20 MHz and the cell's supported bandwidth supports 100 MHz. Since the UE's RF bandwidth supports up to 20 MHz, the UE's active BWP can only support up to 20 MHz. Therefore, when using the frequency hopping scheme according to the above scheme, the frequency diversity gain obtained may be small.

[0423] - As a second example, even if the bandwidth of the RF supported by the terminal is not small, the terminal needs to maintain a small bandwidth of the active BWP for lower energy consumption. In this case, as in the first example, when using the frequency hopping method according to the above method, the frequency diversity gain obtained may be small.

[0424] In order to improve the above frequency hopping transmission method within an active BWP, the following frequency hopping method can be considered.

[0425] FIG. 29 is a diagram illustrating wideband frequency hopping.

[0426] Referring to FIG. 29(a), the first PRB set of hop 0 (hop0) and the second PRB set of hop 1 (hop1) of the terminal may be separated by more than a specific frequency. At this time, one hop may be located within the active BWP. More specifically, the 0th PRB set of hop 0 (hop0) may be located within the active BWP of the terminal, while the 1st PRB set of hop 1 (hop1) may be located in a frequency band away from the active BWP of the terminal. Conversely, the 1st PRB set of hop 1 (hop1) may be located within the active BWP of the terminal, while the 0th PRB set of hop 0 (hop0) may be located in a frequency band away from the active BWP of the terminal. As another example, referring to FIG. 29(b), the first PRB set of hop 0 (hop0) and the second PRB set of hop 1 (hop1) of the terminal may be separated by more than a specific frequency. At this time, the two hops may be located in frequency bands away from the active BWP. More specifically, the 0th PRB set in hop 0 (hop0) and the 1st PRB set in hop 1 (hop1) may be located in a frequency band away from the active BWP of the terminal.

[0427] As illustrated in FIG. 29, a signaling scheme is disclosed for a terminal to transmit one hop or two hops in a frequency band away from an active BWP.

[0428] In the case of PUCCH before RRC connection, it can be determined as follows

[0429] Suppose r PUCCH If is a value of 0, 1, ..., 7, the index of the 0th PRB set of hop 0 of the selected PUCCH resource is

[0430]

number

[0431] and the index of the first PRB set at hop 1 is

[0432]

number

[0433] If r PUCCH If is a value of 8, 9, ..., 15, the index of the 0th PRB set of hop 0 of the selected PUCCH resource is

[0434]

number

[0435] and the index of the first PRB set at hop 1 is

[0436]

number

[0437] Here, N BWP size is the number of PRBs included in a specific BWP that transmits a PUCCH. Here, when the PUCCH transmits HARQ-ACK of Msg4PDSCH, the specific BWP is the initial UL BWP of the general terminal. The initial UL BWP of the general terminal is a UL BWP for a cell connection of the general terminal and is configured in SIB1 (system information block). For reference, the terminal in the above first or second example has an active BWP having a bandwidth smaller than the initial UL BWP of the general terminal. That is, the terminal can determine the 0th PRB set of hop 0 (hop0) and the 1st PRB set of hop 1 (hop1) based on a bandwidth larger than the bandwidth of the active BWP that the terminal may have. Here, if the index of the RB where the 0th PRB set of hop 0 (hop0) starts is 0, it indicates the lowest PRB of the specific BWP. That is, if the index of the RB where the 0th PRB set of hop 0 (hop0) starts is 0, it indicates the lowest PRB of the initial UL BWP of the general terminal.

[0438] In the case of PUCCH after RRC connection, it can be determined as follows.

[0439] The index of the lowest PRB of the 0th PRB set of hop 0 of the PUCCH and the index of the lowest PRB of the 1st PRB set of hop 1 may be configured as a PUCCH resource in the terminal by an RRC signal. That is, when one PUCCH resource is indicated, the terminal can transmit hop 0 and hop 1 using the index of the lowest PRB of the 0th PRB set of hop 0 and the index of the lowest PRB of the 1st PRB set of hop 1 configured in the PUCCH resource. Here, if the PRB index is 0, it indicates the lowest PRB of a specific BWP of the terminal. That is, the PRB index is interpreted as the index of a specific BWP of the terminal. Here, the specific BWP may be one of the following:

[0440] As an example of the specific BWP, the specific BWP may be configured to the terminal from a base station. The UE may be configured with an RB index where the specific BWP starts, or the number of PRBs included in the BWP, from the base station. In this case, the start RB index of the specific BWP may be configured based on the start RB index of an active BWP of the terminal. That is, the difference between the start RB index of the specific BWP and the start RB index of an active BWP of the terminal may be configured.

[0441] As an example of the specific BWP, the terminal may assume the maximum BWP of the cell. The maximum BWP of the cell may be determined as follows: The frequency position of the PRB corresponding to cell common PRB index 0 is set to the terminal at the initial connection to the cell. 275 consecutive PRBs from the cell common PRB index 0 can 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 frequency hop and transmit PUCCH to the terminal at any frequency of the cell.

[0442] As an example of the specific BWP, the terminal can use the initial UL BWP of the general terminal. The initial UL BWP of the general terminal is a UL BWP for a cell connection of the general terminal and is configured in SIB1 (system information block). For reference, the terminal of the first or second example above has an active BWP having a smaller bandwidth than the initial UL BWP of the general terminal.

[0443] In the case of PUSCH, it can be determined as follows.

[0444] (1) First Example

[0445] FIG. 30 is a diagram illustrating wideband frequency hopping according to one embodiment of the present invention.

[0446] Referring to FIG. 30, the UE may determine the 0th PRB set of hop 0 using a DCI for scheduling a PUSCH or a DCI / RRC signal for activating a PUSCH. Here, the DCI for scheduling a PUSCH or the DCI / RRC signal for activating a PUSCH may include a frequency domain resource assignment (FDRA) field. The FDRA field may include an index of an RB where the 0th PRB set of hop 0 starts and the number of consecutive RBs. Here, if the index of an RB where the 0th PRB set of hop 0 starts is 0, it indicates the lowest PRB of the active BWP of the UE. That is, the index of an RB where the 0th PRB set of hop 0 starts is interpreted as the index of the active BWP of the UE. The UE must determine the index of an RB where the 1st PRB set of hop 1 starts. This can be determined by the following mathematical formula:

[0447]

number

[0448] Here, R.B. start (0) represents the index of the RB where the 0th PRB set of hop 0 starts, and RB start (1) represents the index of the RB where the first PRB set of hop 1 begins. offset represents the PRB interval between the 0th PRB set of hop 0 and the 1st PRB set of hop 1. The base station sends the RB offset The RB can be set and instructed. offset The value of RB may be a positive number, 0, or a negative number. offset The value of may be one of −274, −273, ..., 0, ..., 273, 274. If the index of the RB where the first PRB set of hop 1 starts is 0, it indicates the PRB with the lowest active BWP of the terminal. That is, the index of the RB where the first PRB set of hop 1 starts (RB start (1)) is interpreted as the index of the active BWP of the terminal. If the index of the RB where the first PRB set of hop 1 begins is a negative number, it indicates a PRB in a lower frequency band than the active BWP of the terminal. For example, if the index of the RB where the first PRB set of hop 1 begins is -A, it indicates a PRB that is A PRB lower than the lowest PRB of the active BWP of the terminal.

[0449] (2) Second Example

[0450] FIG. 31 is a diagram illustrating wideband frequency hopping according to another embodiment of the present invention.

[0451] Referring to FIG. 31, the UE may determine the 0th PRB set for hop 0 using a DCI for scheduling a PUSCH or a DCI / RRC signal for activating a PUSCH. Here, the DCI for scheduling a PUSCH or the DCI / RRC signal for activating a PUSCH may include a frequency domain resource assignment (FDRA) field. The FDRA field may include an index of an RB where the 0th PRB set for hop 0 starts, and the number of consecutive RBs. Here, if the index of an RB where the 0th PRB set for hop 0 starts is 0, it indicates the lowest PRB of the active BWP of the UE. That is, the index of an RB where the 0th PRB set for hop 0 starts is interpreted as the index of the active BWP of the UE. The UE must determine the index of an RB where the 1st PRB set for hop 1 starts. This can be determined by the following equation:

[0452]

number

[0453] Here, R.B. start (0) represents the index of the RB where the 0th PRB set of hop 0 starts, and RB start (1) represents the index of the RB where the first PRB set of hop 1 begins. offset represents the PRB interval between the 0th PRB set of hop 0 and the 1st PRB set of hop 1. The base station sends the RB offset The terminal may be configured with a specific BWP in which the first PRB set of hop 1 from the base station can be located. This specific BWP is N VBWP size The specific BWP may include an active BWP of the terminal. offset VBWPrepresents the difference between the lowest PRB index of the terminal's active BWP and the lowest index of the particular BWP.

[0454] If the index of the RB where the first PRB set of hop 1 starts is 0, it indicates the PRB with the lowest active BWP of the terminal. That is, the index of the RB where the first PRB set of hop 1 starts (RB start (1)) is interpreted as the index of the active BWP of the terminal. If the index of the RB where the first PRB set of hop 1 begins is a negative number, it indicates a PRB in a lower frequency band than the active BWP of the terminal. For example, if the index of the RB where the first PRB set of hop 1 begins is -A, it indicates a PRB that is A PRB lower than the lowest PRB of the active BWP of the terminal.

[0455] (3) Third Example

[0456] FIG. 32 is a diagram illustrating wideband frequency hopping according to yet another embodiment of the present invention.

[0457] Referring to FIG. 32, in the first or second embodiment, the terminal determines the frequency positions of the 0th PRB set of hop 0 and the 1st PRB set of hop 1. At this time, the active BWP of the terminal is fixed. In the third embodiment of the present invention, a method for the terminal to move the active BWP in the frequency band is proposed. The terminal can determine the 0th PRB set of hop 0 using a DCI for scheduling a PUSCH or a DCI / RRC signal for activating a PUSCH. Here, the DCI for scheduling a PUSCH or the DCI / RRC signal for activating a PUSCH may include a frequency domain resource assignment (FDRA) field. The FDRA field may include an index of an RB where the 0th PRB set of hop 0 starts and the number of consecutive RBs. Here, if the index of an RB where the 0th PRB set of hop 0 starts is 0, it indicates the lowest PRB of the active BWP of the terminal. That is, the index of the RB where the 0th PRB set of hop 0 starts is interpreted as the index of the active BWP of the terminal. The terminal must determine the index of the RB where the 1st PRB set of hop 1 starts. To do this, the active BWP of the terminal may be modified in the frequency domain as follows:

[0458]

number

[0459] Here, N BWP start,μ (0) represents the lowest PRB index of the active BWP that sent hop 0, and N BWP start,μ (1) represents the lowest PRB index of the new active BWP for sending hop 1. offset BWPN represents the interval between the lowest PRB index of an active BWP that transmitted hop 0 and the lowest PRB index of a new active BWP for transmitting hop 1. cell-BW size is the number of PRBs the cell contains. The RB index at which the first PRB set in hop 1 starts is:

[0460]

number

[0461] That is, the RB index where the 0th PRB set of hop 0 starts is the same as the RB index where the 1st PRB set of hop 1 starts. However, since the active BWP that transmitted hop 0 is different from the active BWP that transmitted hop 1, the two hops are transmitted at different frequencies. That is, if the index of the RB where the 1st PRB set of hop 1 starts is 0, it indicates the lowest PRB of the new active BWP of the terminal. That is, the index of the RB where the 1st PRB set of hop 1 starts is interpreted as the index of the new active BWP of the terminal.

[0462] (4) Fourth Example

[0463] FIG. 33 is a diagram illustrating wideband frequency hopping according to one embodiment of the present invention.

[0464] Referring to FIG. 33, in the third embodiment, the terminal transfers the active BWP to the RB offset BWPThe PRB set is moved in the frequency domain according to the value. In the fourth embodiment, frequency hopping is enabled by transmitting hop 0 (hop0) as the 0th active BWP and switching hop 1 (hop1) to the 2nd active BWP. The terminal can determine the 0th PRB set of hop 0 (hop0) using a DCI for scheduling a PUSCH or a DCI / RRC signal for activating a PUSCH. Here, the DCI for scheduling a PUSCH or the DCI / RRC signal for activating a PUSCH may include a frequency domain resource assignment (FDRA) field. The FDRA field may include an index of an RB where the 0th PRB set of hop 0 (hop0) starts and the number of consecutive RBs. Here, if the index of an RB where the 0th PRB set of hop 0 (hop0) starts is 0, it indicates the lowest PRB of the active BWP of the terminal. That is, the index of an RB where the 0th PRB set of hop 0 (hop0) starts is interpreted as the index of the active BWP of the terminal. The terminal must determine the index of the RB where the first PRB set of hop 1 starts. The terminal may indicate or set a second active BWP to determine the index of the RB where the first PRB set of hop 1 starts. Here, the second active BWP may differ from the active BWP in which hop 0 is transmitted in at least a frequency domain or a subcarrier spacing. The terminal may interpret the start index of the RB indicated by the previously obtained FDRA field as the index of the second active BWP to determine the start index of the first PRB set of hop 1. The number of PRBs included in the first PRB set of hop 1 is the same as the number of PRBs included in the 0th PRB set of hop 0.

[0465] In the above first or second embodiment, the terminal transmits a channel and a signal in a frequency band outside the bandwidth of the terminal's RF. In this case, the terminal's RF needs to move from transmitting in the previous frequency band to transmitting in the new frequency band. The time required for this can be called RF switching time. The terminal needs a sufficient amount of RF switching time. In other words, the base station must guarantee the terminal a sufficient amount of RF switching time.

[0466] The RF switching time may be given as a time unit. For example, it may be set as x ms (millisecond) or x us (microsecond). Or, it may be given as x samples. In this case, the time length of one sample is expressed as Ts (second), and the value is Ts=1 / (Δf ref N f,ref )), Δf ref =15 10 3 Hz and N f,ref = 2048. In this case, the time length of one sample is expressed as Tc (seconds), and the value is Tc = 1 / ((Δf max N max )) and Δf max =480 10 3 , N f =4096.

[0467] This time may be set differently for each frequency band. The terminal may determine the number of symbols corresponding to a given value in the time unit. For example, if the given value is x ms, the terminal may divide the x ms by the length of one symbol (symbol_duration) to determine the number of symbols corresponding to x ms. That is, the number of symbols is x ms / symbol_duration. For reference, symbol_duration can be calculated as follows:

[0468] When using a cyclic CP, the length of the OFDM symbol may vary from symbol to symbol. This is because the length of the cyclic prefix (CP) is different. More specifically, when using a cyclic CP, the length of the CP is expressed as follows: When the OFDM symbol index in a subframe is 0 or 7*2, μ Then, 144*κ*2 -μ +16*κ, and the remaining OFDM symbol index is 144*κ*2 -μ where μ is the subcarrier spacing configuration, which is 0 if the subcarrier spacing is 15 kHz, 1 if the subcarrier spacing is 30 kHz, 2 if the subcarrier spacing is 60 kHz, and 3 if the subcarrier spacing is 120 kHz. And κ=Ts / Tc=64.

[0469] The symbol_duration for calculating the number of symbols can be a shorter one of the lengths of the symbols. That is, the symbol_duration is 144*κ*2 -μ *Tc (seconds). The reason for using such a short length is to obtain the minimum number of symbols to guarantee RF switching time.

[0470] As another example, when transmitting an uplink channel, a terminal can obtain beam diversity by transmitting using different beams. At this time, time is required for the terminal to switch the beam from the first beam to the second beam. This can be called a beam switching time. The terminal must meet the beam switching time. To this end, the base station can set a time required for beam switching to the terminal similar to the RF switching time, and the terminal can determine the number of symbols required for the beam switching time.

[0471] In the following description of the present invention, the number of symbols for ensuring the RF switching time or the beam switching time is represented as G. For reference, when a terminal needs RF switching due to frequency hopping and needs beam switching due to beam change, the G value may be determined based on the sum or maximum value of the RF switching time or the beam switching time. The terminal cannot transmit an uplink signal during the G symbols.

[0472] The problem to be solved by the present invention is to provide a method for allocating G symbols that cannot transmit an uplink signal / channel when transmitting an uplink channel or signal. The following describes a method for allocating G symbols that cannot transmit an uplink signal / channel.

[0473] Also, for convenience, the present invention describes a method of arranging G symbols to meet the RF switching time during frequency hopping, which may be interpreted as a method of arranging G symbols to meet the beam switching time by replacing frequency hopping with beam changing.

[0474] FIG. 34 is a diagram illustrating a PUSCH repetition type B according to an example.

[0475] Referring to Figure 34, the terminal is scheduled to repeat (K=4) the PUSCH with length 4 (L=4) four times from symbol 8 (S=8) of slot 0. As shown in Figure 34(a), the terminal can create four nominal repetitions of four symbols each from symbol 8 of slot 0. Here, nominal repetition 0 includes symbols 8, 9, 10, and 11 of slot 0, nominal repetition 1 includes symbols 12 and 13 of slot 0 and symbols 0 and 1 of slot 1, nominal repetition 2 includes symbols 2, 3, 4, and 5 of slot 1, and nominal repetition 3 includes symbols 6, 7, 8, and 9 of slot 1.

[0476] As shown in FIG. 34(b), the nominal repetition may be split at slot boundaries (although not shown in the drawing, splitting may also occur around symbols where UL transmission is not enabled), and an actual repetition may be generated by combining consecutive symbols in one slot. Referring to FIG. 34(b), nominal repetition 1 may be split into two actual repetitions. Thus, the terminal can transmit PUSCH with five actual repetitions. More specifically, actual repetition 0 includes symbols 8, 9, 10, and 11 in slot 0, actual repetition 1 includes symbols 12 and 13 in slot 0, actual repetition 2 includes symbols 0 and 1 in slot 1, actual repetition 3 includes symbols 2, 3, 4, and 5 in slot 1, and actual repetition 4 includes symbols 6, 7, 8, and 9 in slot 1.

[0477] In the following figures, only the index of the actual iteration is shown, i.e., if 0 is shown, it is the actual iteration 0.

[0478] In Fig. 34, the terminal performs frequency hopping for each nominal repetition. That is, the nominal repetition of an even index is transmitted in the 0th PRB set of hop 0, and the nominal repetition of an odd index is transmitted in the 1st PRB set of hop 1. For convenience of explanation of the present invention, the terminal performs frequency hopping for each nominal repetition, but the method of the present invention can be applied to other frequency hopping methods.

[0479] A terminal requires G symbols for RF switching during frequency hopping. That is, at least G symbols are required between transmission in the 0th PRB set in hop 0 and transmission in the 1st PRB set in hop 1. A method for ensuring G symbols is disclosed. This is a first embodiment of PUSCH repetition type B of the present invention, and refers to FIG. 35.

[0480] FIG. 35 illustrates a type-B PUSCH repetition in which a gap symbol is placed in a previous nominal repetition according to one embodiment of the present invention.

[0481] Referring to FIG. 35, the terminal can use G symbols just before frequency hopping as a gap without transmitting PUSCH. Referring to FIG. 35(a), when G=1, one symbol just before frequency hopping can be used as a gap for RF switching without transmitting PUSCH. Referring to FIG. 35(b), when G=2, two symbols just before frequency hopping can be used as a gap for RF switching without transmitting PUSCH. Frequency hopping occurs between nominal repetition 0 (symbols 8, 9, 10, 11 of slot 0) and nominal repetition 1 (symbols 12, 13 of slot 0 and symbols 0, 1 of slot 1). Therefore, according to an embodiment of the present invention, the last G symbols of nominal repetition 0 just before frequency hopping can be determined as symbols that do not transmit PUSCH. Therefore, the symbols that do not transmit the PUSCH may be excluded when determining the actual repetition (when determining the actual repetition, the symbols that do not transmit the PUSCH are determined as invalid symbols).

[0482] Referring to FIG. 35(a), when G=1, symbol 11 of slot 0, symbol 1 of slot 1, and symbol 5 of slot 1 may be determined as symbols that do not transmit PUSCH. Thus, the terminal can configure actual repetition 0 by grouping symbols 8, 9, and 10 of slot 0, actual repetition 1 by grouping symbols 12 and 13 of slot 0, actual repetition 2 by grouping symbols 2, 3, and 4 of slot 1, and actual repetition 3 by grouping symbols 6, 7, 8, and 9 of slot 1. For reference, symbol 0 of slot 1 is a single symbol, so PUSCH is not transmitted. This symbol is called an orphan symbol.

[0483] 35(b), when G=2, symbols 10 and 11 in slot 0, symbols 0 and 1 in slot 1, and symbols 4 and 5 in slot 1 may be determined as symbols that do not transmit a PUSCH. As a result, the terminal can configure actual repetition 0 by combining symbols 8 and 9 in slot 0, actual repetition 1 by combining symbols 12 and 13 in slot 0, actual repetition 2 by combining symbols 2 and 3 in slot 1, and actual repetition 3 by combining symbols 6, 7, 8, and 9 in slot 1.

[0484] A second embodiment of the PUSCH repetition type B of the present invention is shown in FIG.

[0485] FIG. 36 is a diagram illustrating a type-B PUSCH repetition in which a gap symbol is placed in a subsequent nominal repetition according to one embodiment of the present invention.

[0486] Referring to FIG. 36, the UE may use G symbols immediately after frequency hopping as gaps for RF switching without transmitting PUSCH. Referring to FIG. 36(a), when G=1, one symbol immediately after frequency hopping may use PUSCH as gaps for RF switching without transmitting PUSCH. Referring to FIG. 36(b), when G=2, two symbols immediately after frequency hopping may use PUSCH as gaps for RF switching without transmitting PUSCH. Frequency hopping occurs between nominal repetition 0 (symbols 8, 9, 10, 11 of slot 0) and nominal repetition 1 (symbols 12, 13 of slot 0 and symbols 0, 1 of slot 1). Therefore, according to an embodiment of the present invention, the first G symbols of nominal repetition 1 immediately after frequency hopping may be determined as symbols that do not transmit PUSCH. Therefore, the symbols that do not transmit PUSCH may be excluded when determining actual repetition (when determining actual repetition, the symbols that do not transmit PUSCH are determined as invalid symbols).

[0487] Referring to FIG. 36(a), when G=1, symbol 12 of slot 0, symbol 2 of slot 1, and symbol 6 of slot 1 may be determined as symbols that do not transmit PUSCH. Thus, the terminal can configure actual repetition 0 by grouping symbols 8, 9, 10, and 11 of slot 0, actual repetition 1 by grouping symbols 0 and 1 of slot 1, actual repetition 2 by grouping symbols 3, 4, and 5 of slot 1, and actual repetition 3 by grouping symbols 7, 8, and 9 of slot 1. For reference, symbol 13 of slot 0 is one symbol, so PUSCH is not transmitted. This symbol is called an orphan symbol.

[0488] 36(b), when G=2, symbols 12 and 13 in slot 0, symbols 2 and 3 in slot 1, and symbols 6 and 7 in slot 1 may be determined as symbols that do not transmit PUSCH. As a result, the terminal can configure actual repetition 0 by combining symbols 8, 9, 10, and 11 in slot 0, actual repetition 1 by combining symbols 0 and 1 in slot 1, actual repetition 2 by combining symbols 4 and 5 in slot 1, and actual repetition 3 by combining symbols 8 and 9 in slot 1.

[0489] The second embodiment has the following advantages over the first embodiment. When low latency is required, such as in a URLLC system, it is preferable to transmit the PUSCH as early as possible (early in time) with as many symbols as possible. Comparing the number of symbols included in the first actual iteration of the first embodiment and the second embodiment, the second embodiment can transmit the PUSCH with more symbols since there are no symbols used as gaps. Therefore, the base station has a higher probability of correctly receiving the PUSCH at an earlier point in time.

[0490] However, in the first and second embodiments, since G symbols are not used for PUSCH transmission in one of the nominal repetitions, the number of symbols between repetitions differs. For example, in FIG. 35(b), actual repetitions 0, 1, and 2 occupy 2 symbols, but actual repetition 3 occupies 4 symbols. Therefore, the difference in the number of symbols between repetitions may cause degradation of PUSCH reception performance.

[0491] A third embodiment of the PUSCH repetition type B of the present invention is shown in FIG.

[0492] FIG. 37 is a diagram illustrating gap symbols being distributed in a Type-B PUSCH repetition according to one embodiment of the present invention.

[0493] Referring to FIG. 37, the terminal does not need to transmit the PUSCH with f(G / 2) symbols immediately before frequency hopping, and does not need to transmit the PUSCH with Gf(G / 2) symbols immediately after frequency hopping, where 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 the repetitions can be reduced by avoiding the use of the same number of symbols for PUSCH transmission in the nominal repetition immediately before and immediately after frequency hopping, as much as possible.

[0494] 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 may be determined as symbols that do not transmit PUSCH. Thus, the terminal can configure actual repetition 0 by grouping symbols 8, 9, and 10 of slot 0, configure actual repetition 1 by grouping symbols 3 and 4 of slot 1, and configure actual repetition 2 by grouping symbols 7, 8, and 9 of slot 1. For reference, symbol 13 of slot 0 is 1 symbol, so PUSCH is not transmitted. Also, symbol 0 of slot 1 is 1 symbol, so PUSCH is not transmitted.

[0495] Referring to FIG. 37, according to the third embodiment, it can be confirmed that the number of symbols in each r - repetition of the terminal is similar. In FIG. 37, actually, repetition 0 and 2 occupy 3 symbols, and repetition 1 occupies 2 symbols. However, in FIG. 37, symbol 13 in slot 0 and symbol 0 in slot 1 are orphan symbols where PUSCH is not transmitted. Therefore, the total number of symbols used for PUSCH is reduced. A method to solve this is needed.

[0496] As a fourth embodiment of PUSCH repetition type B of the present invention, the terminal can compare the number of symbols in the actual repetition immediately before frequency hopping with the number of symbols in the actual repetition immediately after frequency hopping, and determine G symbols where PUSCH is not transmitted. Here, in the actual repetition with a larger number, some or all of the symbols can be preferentially determined as symbols where PUSCH is not transmitted. The specific method is as follows.

[0497] As a first method, the terminal compares the number of symbols in the actual repetition immediately before frequency hopping with the number of symbols in the actual repetition immediately after frequency hopping, and in the actual repetition with a larger number of symbols, G symbols can be determined as symbols where PUSCH is not transmitted. Here, when the number of symbols in the actual repetition immediately before frequency hopping is N1 and the number of symbols in the actual repetition immediately after frequency hopping is N2, the G symbols can be determined as follows.

[0498] - If N1≧N2, the last G symbols in the actual repetition immediately before frequency hopping are determined as symbols where PUSCH is not transmitted.

[0499] - If N1<N2, the first G symbols in the actual repetition immediately after frequency hopping are determined as symbols where PUSCH is not transmitted.

[0500] As a second method, the terminal compares the number of symbols (N1) of the actual repetition immediately before frequency hopping and the number of symbols (N2) of the actual repetition immediately after frequency hopping, and can determine that one symbol in the actual repetition with a larger number of symbols is a symbol in which PUSCH is not transmitted. 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. This operation is repeated until G symbols are obtained. More specifically, it is obtained as follows.

[0501] - Let g1 = 0 and g2 = 0.

[0502] - If g1 + g2 < G, the following process is repeated. If N1 - g1 ≥ N2 - g2, then g1 = g1 + 1. If N1 - g1 < N2 - g2, then g2 = g2 + 1.

[0503] - Determine that the last g1 symbols of the actual repetition immediately before frequency hopping are symbols in which PUSCH is not transmitted.

[0504] - Determine that the first g2 symbols of the actual repetition immediately after frequency hopping are symbols in which PUSCH is not transmitted.

[0505] Also, as a third method, G symbols may be determined as follows.

[0506] - If N1 ≥ N2 and N1 - N2 ≥ G, determine that the last G symbols of the actual repetition immediately before frequency hopping are symbols in which PUSCH is not transmitted.

[0507] - If N1≥N2 and N1 - N2 < G, then for the last N1 - N2 + f((G - (N1 - N2)) / 2) symbols of the actual repetition immediately before frequency hopping, it is determined that these symbols are not PUSCH - transmitted symbols, and for the first G - (N1 - N2) - f((G - (N1 - N2)) / 2) symbols of the actual repetition immediately after frequency hopping, it is determined that these symbols are not PUSCH - transmitted symbols.

[0508] - If N1 < N2 and N2 - N1≥G, then for the first G symbols of the actual repetition immediately after frequency hopping, it is determined that these symbols are not PUSCH - transmitted symbols.

[0509] - If N1 < N2 and N2 - N1 < G, then for the last G - (N2 - N1) - f((G - (N2 - N1)) / 2) symbols of the actual repetition immediately before frequency hopping, it is determined that these symbols are not PUSCH - transmitted symbols, and for the first N2 - N1 + f((G - (N2 - N1)) / 2) symbols of the actual repetition immediately after frequency hopping, it is determined that these symbols are not PUSCH - transmitted symbols.

[0510] The fourth embodiment of the PUSCH repetition type B of the present invention is as shown in FIG. 38.

[0511] FIG. 38 is a diagram showing that in the type B PUSCH repetition according to an embodiment of the present invention, gap symbols are arranged in the nominal repetition having a larger number.

[0512] According to the first method, the terminal determines the symbols where PUSCH is not transmitted as follows. First, the terminal obtains the actual repetition assuming G = 0 (without considering the gap). The actual repetition obtained here is as shown in FIG. 34(b). The actual repetition obtained here is an intermediate process and is called the intermediate actual repetition for convenience. The actual repetition actually transmitted with the symbols where PUSCH is not transmitted is obtained as follows.

[0513] According to FIG. 34(b), the number of intermediate actual repetitions is 5, and the indexes are 0, 1, 2, 3, and 4. Frequency hopping occurs between intermediate actual repetitions 0 and 1, frequency hopping occurs between intermediate actual repetitions 2 and 3, and frequency hopping occurs between intermediate actual repetitions 3 and 4. First, a gap for frequency hopping that is the earliest in time is determined. 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 that includes more symbols are determined as symbols for which PUSCH is not transmitted. A gap for frequency hopping that is the next in time is determined. 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 that includes more symbols are determined as symbols for which PUSCH is not transmitted. Finally, a gap for frequency hopping at the end in time is determined. Intermediate actual repetition 3 includes 3 (if G=1 in FIG. 38(a)) or 2 (if G=2 in FIG. 38(b)) symbols, and intermediate actual repetition 4 includes 4 symbols. Thus, the first G symbols of intermediate actual repetition 4 including more symbols are determined as symbols on which PUSCH is not transmitted. The terminal can determine the actual repetition by excluding the determined symbols on which PUSCH is not transmitted in the intermediate actual repetition.

[0514] According to the fourth embodiment of the PUSCH repetition type B of the present invention, some symbols in an actual repetition having a longer length are determined as symbols on which PUSCH is not transmitted. Therefore, the length of the actual repetition is reduced overall. As a result, one actual repetition cannot have a lower code rate. A method for solving this is required.

[0515] As a fifth embodiment of PUSCH repetition type B of the present invention, the terminal can compare the number of symbols of the actual repetition immediately before frequency hopping and the number of symbols of the actual repetition immediately after frequency hopping, and determine G symbols where PUSCH is not transmitted. Here, in the actual repetition with the smaller number, some or all of the symbols can be preferentially determined as symbols where PUSCH is not transmitted. The specific method is as follows.

[0516] As a first method, the terminal compares the number of symbols of the actual repetition immediately before frequency hopping and the number of symbols of the actual repetition immediately after frequency hopping, and in the actual repetition with the smaller number of symbols, G symbols can be determined as symbols where 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.

[0517] - If N1 ≥ N2, the first G symbols of the actual repetition immediately after frequency hopping are determined as symbols where PUSCH is not transmitted.

[0518] - If N1 < N2, the last G symbols of the actual repetition immediately before frequency hopping are determined as symbols where PUSCH is not transmitted.

[0519] As a second method, the terminal compares the number of symbols (N1) of the actual repetition immediately before frequency hopping and the number of symbols (N2) of the actual repetition immediately after frequency hopping, and in the actual repetition with the smaller number of symbols, one symbol can be determined as a symbol where PUSCH is not transmitted. 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. This operation is repeated until G symbols are obtained. More specifically, it is obtained as follows.

[0520] - Let g1 = 0 and g2 = 0.

[0521] - 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.

[0522] - Determine the last g1 symbols of the actual iteration immediately before frequency hopping as symbols where PUSCH is not transmitted.

[0523] - Determine the first g2 symbols of the actual iteration immediately after frequency hopping as symbols where PUSCH is not transmitted.

[0524] Also, as a third method, the G symbols may be determined as follows.

[0525] - If N1 ≥ N2 and N2 ≥ G, determine the first G symbols of the actual iteration immediately after frequency hopping as symbols where PUSCH is not transmitted.

[0526] - If N1 ≥ N2 and N2 < G, determine all N2 symbols of the actual iteration immediately after frequency hopping as symbols where PUSCH is not transmitted, and determine the last G - N2 symbols of the actual iteration immediately before frequency hopping as symbols where PUSCH is not transmitted.

[0527] - If N1 < N2 and N1 ≥ G, determine the last G symbols of the actual iteration immediately before frequency hopping as symbols where PUSCH is not transmitted.

[0528] - If N1 < N2 and N1 < G, determine all N1 symbols of the actual iteration immediately before frequency hopping as symbols where PUSCH is not transmitted, and determine the first G - N1 symbols of the actual iteration immediately after frequency hopping as symbols where PUSCH is not transmitted.

[0529] The fifth embodiment of PUSCH repetition type B of the present invention is as shown in FIG. 39.

[0530] FIG. 39 is a diagram illustrating a type-B PUSCH repetition in which gap symbols are arranged in a nominal repetition having a small number in accordance with one embodiment of the present invention.

[0531] According to the first method, the terminal determines symbols on which PUSCH is not transmitted as follows. First, the terminal determines actual repetitions assuming G=0 (without considering gaps). The actual repetitions determined here are as shown in FIG. 34(b). The actual repetitions determined here are intermediate processes and are referred to as intermediate actual repetitions for convenience, and the actual repetitions actually transmitted by symbols on which PUSCH is not transmitted are determined as follows.

[0532] According to FIG. 34(b), there are five intermediate actual repetitions, and the indexes are 0, 1, 2, 3, and 4. Frequency hopping occurs between intermediate actual repetitions 0 and 1, frequency hopping occurs between intermediate actual repetitions 2 and 3, and frequency hopping occurs between intermediate actual repetitions 3 and 4. First, a gap for the frequency hopping that is the earliest in time is determined. Intermediate actual repetition 0 includes 4 symbols, and intermediate actual repetition 1 includes 2 symbols. Therefore, the first G symbols of intermediate actual repetition 1 that includes fewer symbols are determined as symbols for which PUSCH is not transmitted. A gap for the next frequency hopping in time is determined. Intermediate actual repetition 2 includes 2 symbols, and intermediate actual repetition 3 includes 4 symbols. Therefore, the last G symbols of intermediate actual repetition 2 that includes fewer symbols are determined as symbols for which PUSCH is not transmitted. Finally, the gap for frequency hopping that is the latest in time is determined. Intermediate actual repetition 3 includes 4 symbols, and intermediate actual repetition 4 includes 4 symbols. Therefore, since the number of symbols is the same, the last G symbols of the preceding intermediate actual repetition 3 are determined as symbols on which PUSCH is not transmitted. The terminal can determine the actual repetition by excluding the determined symbols on which PUSCH is not transmitted in the intermediate actual repetition. For reference, when G=1, intermediate actual repetitions 1 and 2 each include one symbol. Therefore, the one symbol is an orphan symbol on which PUSCH is not transmitted.

[0533] Referring to Figure 39, it can be seen that the UE transmits the PUSCH in the actual repetition containing more symbols. However, according to Figure 39 (a), if G symbols are not used for PUSCH transmission in the intermediate actual repetition containing a small number of symbols, the remaining symbol becomes one and may become an orphan symbol. Due to this orphan symbol, the total number of symbols used for PUSCH transmission is exhausted. A method for solving this is needed.

[0534] As a sixth embodiment of the PUSCH repetition type B of the present invention, the terminal can determine G symbols that do not transmit PUSCH by comparing 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. Here, some or all symbols can be preferentially determined as symbols that do not transmit PUSCH in the actual repetition having a smaller number. However, if the actual repetition is two symbols, symbols that do not transmit PUSCH in the actual repetition are not further determined, and symbols that do not transmit PUSCH can be determined in the actual repetition having a larger number. A specific method is as follows.

[0535] As a first method, the terminal 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, and determine that G symbols in the actual repetition having a smaller number of symbols are symbols that do not transmit PUSCH. 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:

[0536] If N1≧N2 and N2−G≧2, determine the first G symbols of the actual repetition immediately after frequency hopping as symbols on which PUSCH is not transmitted.

[0537] - If N1 ≥ N2 and N2 - G < 2, determine that the first N2 - 2 symbols of the actual repetition immediately after frequency hopping are symbols in which PUSCH is not transmitted. Determine that the last G - (N2 - 2) symbols of the actual repetition immediately before frequency hopping are symbols in which PUSCH is not transmitted.

[0538] - If N1 < N2 and N1 - G ≥ 2, determine that the last G symbols of the actual repetition immediately before frequency hopping are symbols in which PUSCH is not transmitted.

[0539] - If N1 < N2 and N1 - G < 2, determine that the last N1 - 2 symbols of the actual repetition immediately before frequency hopping are symbols in which PUSCH is not transmitted. Determine that the first G - (N1 - 2) symbols of the actual repetition immediately after frequency hopping are symbols in which PUSCH is not transmitted.

[0540] As a second method, the terminal compares the number of symbols (N1) of the actual repetition immediately before frequency hopping with the number of symbols (N2) of the actual repetition immediately after frequency hopping, and can determine that one symbol in the actual repetition having a smaller number of symbols is a symbol in which PUSCH is not transmitted. 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, it is obtained as follows.

[0541] - Let g1 = 0 and g2 = 0.

[0542] - If g1 + g2 < G, repeat the following process. If N1 - g1 ≥ N2 - g2 ≥ 2, then g2 = g2 + 1. Otherwise, g1 = g1 + 1.

[0543] - Determine that the last g1 symbols of the actual repetition immediately before frequency hopping are symbols in which PUSCH is not transmitted.

[0544] - Determine the first g2 symbols of the actual repetition immediately after frequency hopping as symbols in which PUSCH is not transmitted.

[0545] Also, as a third method, the G symbols may be determined as follows.

[0546] - If N1≥N2 and N2 - G≥2, determine the first G symbols of the actual repetition immediately after frequency hopping as symbols in which PUSCH is not transmitted.

[0547] - If N1≥N2 and N2 - G<2, determine the first N2 - 2 symbols of the actual repetition immediately after frequency hopping as symbols in which PUSCH is not transmitted, and determine the last G-(N2 - 2) symbols of the actual repetition immediately before frequency hopping as symbols in which PUSCH is not transmitted.

[0548] - If N1<N2 and N1 - G≥2, determine the last G symbols of the actual repetition immediately before frequency hopping as symbols in which PUSCH is not transmitted.

[0549] - If N1<N2 and N1 - G<2, determine the N1 - 2 symbols of the actual repetition immediately before frequency hopping as symbols in which PUSCH is not transmitted, and determine the first G-(N1 - 2) symbols of the actual repetition immediately after frequency hopping as symbols in which PUSCH is not transmitted.

[0550] The sixth embodiment of the PUSCH repetition type B of the present invention is as shown in FIG. 40.

[0551] FIG. 40 is a diagram showing that gap symbols are arranged so that orphan symbols do not occur in the type B PUSCH repetition according to an embodiment of the present invention.

[0552] According to the first method, the terminal determines symbols on which PUSCH is not transmitted as follows: First, the terminal determines actual repetitions assuming G=0 (without considering gaps). The actual repetitions determined here are as shown in FIG. 34(b). The actual repetitions determined here are intermediate processes and are referred to as intermediate actual repetitions for convenience, and the actual repetitions actually transmitted by symbols on which PUSCH is not transmitted are determined as follows:

[0553] According to FIG. 34(b), the number of intermediate actual repetitions is 5, and the indexes are 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, a gap for the frequency hopping that is the earliest in time is determined. Intermediate actual repetition 0 includes 4 symbols, and intermediate actual repetition 1 includes 2 symbols. Therefore, since intermediate actual repetition 1, which includes fewer symbols, includes 2 symbols, this intermediate actual repetition cannot include any more symbols on which PUSCH is not transmitted (if it does, an orphan symbol occurs). Therefore, in intermediate actual repetition 0, which includes a larger number of symbols, the last G symbols are determined as symbols on which PUSCH is not transmitted. A gap for the next frequency hopping in time is determined. Intermediate actual repetition 2 includes two symbols, and intermediate actual repetition 3 includes four symbols. Since intermediate actual repetition 2, which includes fewer symbols, includes two symbols, this intermediate actual repetition cannot include any more symbols on which PUSCH is not transmitted (otherwise, orphan symbols will occur). Therefore, in intermediate actual repetition 3, which includes a larger number of symbols, the last G symbols are determined as symbols on which PUSCH is not transmitted. Finally, the gap for frequency hopping that is the latest in time is determined. Intermediate actual repetition 3 includes three (when G=1 in FIG. 40(a)) or two (when G=2 in FIG. 40(b)) symbols, and intermediate actual repetition 4 includes four symbols. If the intermediate actual repetition 3 is three (G=1 in FIG. 40(a)), the last G=1 symbols of the intermediate actual repetition 3 are determined as symbols on which PUSCH is not transmitted.If intermediate actual repetition 3 is two (G=2 in FIG. 40(b)), the first G=2 symbols of intermediate actual repetition 4 are determined as symbols on which PUSCH is not transmitted.

[0554] From FIG. 40 it can be seen that the actual repetitions transmitted by the terminal have no more orphan symbols.

[0555] In the first to sixth embodiments of the PUSCH repetition type B of the present invention, some or all symbols are determined as symbols that are not transmitted as PUSCH in the nominal repetition or actual repetition that has already been obtained. However, in this case, the number of symbols that the terminal actually uses for PUSCH transmission may be reduced. As a result, the reliability of PUSCH transmission is reduced. A method for solving this problem is disclosed.

[0556] According to the seventh embodiment of the PUSCH repetition type B of the present invention, the terminal can determine the nominal repetition by considering G symbols. More specifically, the terminal is instructed or configured by the base station with the starting symbol index (S) of the first nominal repetition, the number of symbols (L) included in the nominal repetition, and the number of nominal repetitions (K) to determine the nominal repetition. The terminal creates the first nominal repetition by combining L symbols starting from the starting symbol index (S) of the first nominal repetition. Then, it creates the second nominal repetition by combining L symbols from the next symbol. In this way, K nominal repetitions are generated.

[0557] If the terminal cannot transmit PUSCH with G symbols during frequency hopping, the terminal can determine the nominal repetition as follows: The terminal creates the first nominal repetition by grouping L symbols starting from the starting symbol index (S) of the first nominal repetition. Then, it determines G symbols from the next symbol of the first nominal repetition as symbols on which PUSCH is not transmitted. Then, it creates the second nominal repetition by grouping L symbols from the next symbol. Then, it determines G symbols from the next symbol of the first nominal repetition as symbols on which PUSCH is not transmitted. In this way, K nominal repetitions are generated.

[0558] FIG. 41 is a diagram illustrating a type-B PUSCH repetition in which a gap symbol is added after a nominal repetition according to one embodiment of the present invention.

[0559] Referring to FIG. 41(a), S=8, L=4, K=4, and G=1. The terminal groups together symbols 8, 9, 10, and 11 of slot 0 to form the first nominal repetition. Then, the terminal determines that the next G=1 symbol (symbol 12 of slot 0) is a symbol on which PUSCH is not transmitted. Then, the terminal groups 13 of slot 0 and symbols 0, 1, and 2 of slot 1 to form the second nominal repetition. Then, the terminal determines that the next G=1 symbol (symbol 3 of slot 1) is a symbol on which PUSCH is not transmitted. Then, the terminal groups symbols 4, 5, 6, and 7 of slot 1 to form the third nominal repetition. Then, the terminal determines that the next G=1 symbol (symbol 8 of slot 1) is a symbol on which PUSCH is not transmitted. Finally, the terminal groups symbols 9, 10, 11, and 12 of slot 1 to form the fourth nominal repetition. The nominal repetition obtained in this manner may be divided into actual repetitions.

[0560] Referring to FIG. 41(b), S=8, L=4, K=4, and G=2. The terminal groups together symbols 8, 9, 10, and 11 of slot 0 to form the first nominal repetition. Then, it determines that the next G=2 symbol (symbols 12 and 13 of slot 0) is a symbol that PUSCH is not transmitted. Then, it groups together symbols 0, 1, 2, and 3 of slot 1 to form the second nominal repetition. Then, it determines that the next G=2 symbol (symbols 4 and 5 of slot 1) is a symbol that PUSCH is not transmitted. Then, it groups together symbols 6, 7, 8, and 9 of slot 1 to form the third nominal repetition. Then, it determines that the next G=2 symbol (symbols 10 and 11 of slot 1) is a symbol that PUSCH is not transmitted. Finally, it groups symbols 12 and 13 of slot 1 and symbols 0 and 1 of slot 2 to form the fourth nominal repetition. The nominal repetition obtained in this manner may be divided into actual repetitions.

[0561] In the seventh embodiment of the PUSCH repetition type B of the present invention, a symbol that does not transmit a PUSCH is inserted between the nominal repetitions. However, some symbols in the nominal repetitions may not be transmitted. For example, an invalid UL symbol (DL symbol, SSB symbol, CORESET#0 symbol, symbol set by RRC signal) is not transmitted. Or, if the number of consecutive symbols in one slot among the symbols in the nominal repetition is one, the symbol is not transmitted because it is an orphan symbol. Therefore, it is not necessary to always insert a symbol that does not transmit a PUSCH between the nominal repetitions. An embodiment for solving this problem will be disclosed below.

[0562] In the eighth embodiment of the PUSCH repetition type B of the present invention, the terminal can determine the nominal repetition and the actual repetition by considering G symbols, invalid UL symbols, and orphan symbols. More specifically, if the terminal cannot transmit PUSCH in G symbols during frequency hopping, the terminal can determine the first nominal repetition. The terminal creates the first nominal repetition by gathering L symbols starting from the starting symbol index (S) of the first nominal repetition. The terminal obtains the actual repetition from the first nominal repetition. Then, the terminal determines G symbols after the last symbol of the actual repetition as symbols on which PUSCH is not transmitted. Then, the terminal can determine the second nominal repetition by gathering L symbols after the G symbols. The terminal obtains the actual repetition from the second nominal repetition. The terminal determines G symbols after the last symbol of the obtained actual repetition as symbols on which PUSCH is not transmitted. In this manner, K nominal repetitions and an actual repetition are created from the K nominal repetitions.

[0563] FIG. 42 is a diagram illustrating gap symbols taking into consideration invalid UL symbols and orphan symbols in Type-B PUSCH repetition according to one embodiment of the present invention.

[0564] Referring to FIG. 42(a), S=8, L=4, K=4, and G=1. The terminal creates 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 terminal determines that the next G=1 symbol (symbol 12 of slot 0) is a symbol on which PUSCH is not transmitted. Then, the terminal creates 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 excluded from the actual repetition because it is an orphan symbol, and symbol 2 of slot 1 is excluded from the actual repetition because it is an invalid UL symbol. Therefore, the last symbol of the actual repetition is symbol 1 of slot 1. The G=1 symbol (symbol 2 in slot 1) following this symbol is determined as a symbol in which PUSCH is not transmitted. In this manner, K=4 nominal repetitions and actual repetitions are generated from the K=4 nominal repetitions.

[0565] Referring to FIG. 42(b), S=8, L=4, K=4, and G=2. The terminal groups together symbols 8, 9, 10, and 11 of slot 0 to form a first nominal repetition. An actual repetition is obtained from the first nominal repetition. This actual repetition includes symbols 8, 9, 10, and 11 of slot 0. It is determined that the next G=2 symbols (symbols 12 and 13 of slot 0) are symbols for which PUSCH is not transmitted. Then, the terminal groups together symbols 0, 1, 2, and 3 of slot 1 to form a second nominal repetition. An 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 excluded from the actual repetition because it is an invalid UL symbol. And symbol 3 of slot 1 is excluded from the actual repetition because it is an orphan symbol. Therefore, the last symbol of the actual repetition is symbol 1 of slot 1. The G=2 symbols (symbols 2 and 3 in slot 1) following this symbol are determined as symbols in which PUSCH is not transmitted. In this manner, K=4 nominal repetitions and actual repetitions are generated from the K=4 nominal repetitions.

[0566] The above description of the present invention is for illustrative purposes only, and those skilled in the art will understand that the present invention can be easily modified into other specific forms without changing the technical idea or essential features of the present invention. Therefore, the above-described embodiments should be understood as illustrative and not restrictive in all respects. For example, each component described as a single type may be implemented in a distributed manner, and similarly, each component described as distributed may be implemented in a combined form.

[0567] The scope of the present invention is defined by the claims set forth below rather than the above detailed description, and all modifications and variations that fall within the meaning and scope of the claims, as well as their equivalents, should be interpreted as being included within the scope of the present invention. [Explanation of symbols]

[0568] 100 devices 110 Processor 120 Communication Module 121 Cellular communication interface card 122 Cellular communication interface card 123 Unlicensed spectrum communication interface card 130 Memory 140 User Interface 150 display units 200 base stations 210 Processor 220 Communication Module 221 Cellular communication interface card 222 Cellular communication interface card 223 Unlicensed spectrum communication interface card 230 Memory

Claims

1. A first terminal having reduced capability in a wireless communication system, A communication module configured to receive configuration information for setting a first downlink bandwidth part (DL BWP) and a first uplink bandwidth part (Uplink BWP) used in an initial access procedure, receive an indicator indicating BWP access barring of the first terminal in a second UL BWP and a second DL BWP for a second terminal of a legacy type, and perform an initial access procedure in 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 for controlling the reception of the configuration information, the execution of the initial connection procedure, and the reception of the indicator; The first UL BWP and the second UL BWP are set individually, The initial access procedure includes a random access procedure, The first UL BWP includes first resources for the optional connection procedure of the first terminal; The first resource is the same as a second resource for an optional connection procedure on a second UL BWP of the second terminal.

2. The communication module includes: The first terminal of claim 1, configured to obtain information about a control resource set (CORESET) from a second synchronization signal block (SSB) related to the second terminal.

3. The communication module includes: The first terminal according to claim 2, characterized in that it is configured to receive information regarding a CORESET for the first terminal, which is defined separately from the CORESET for the second terminal, using a system information block 1 (SIB1).

4. The communication module is configured to receive a SIB1 for the second terminal; The first terminal according to claim 2, wherein the SIB1 includes scheduling information related to system information for performing the initial access procedure of the first terminal.

5. The first terminal of claim 4, wherein the scheduling information includes information regarding a start physical resource block (PRB) of the first DL BWP activated for performing an initial access procedure of the first terminal.

6. The communication module is configured to receive a SIB1 for the second terminal; The first terminal of claim 2, wherein the SIB1 includes configuration information for an optional access procedure for an initial access of the first terminal.

7. The communication module includes:

2. The first terminal of claim 1, configured to obtain information about a CORESET for the first terminal from a first SSB defined separately from a second SSB related to the second terminal.

8. The information about the basic CORESET is composed of 8 bits, The first terminal according to claim 2, characterized in that in the information regarding the basic CORESET, 4 bits indicate information regarding a frequency domain in which the basic CORESET is set, and the remaining 4 bits indicate information regarding a symbol for monitoring the basic CORESET.

9. The first terminal according to claim 8, wherein the 8 bits constituting the information on the basic CORESET are recognized as different information by the first terminal and the second terminal.

10. The first terminal of claim 1 , wherein the communication module receives information indicating the first resource for the first terminal from a base station.

11. The first terminal according to claim 1 , characterized in that a part of an optional connection preamble sequence available in a cell provided by a base station is used for the first terminal, and the remaining part is used for the second terminal.

12. The communication module includes: The first terminal according to claim 2, characterized in that information about a CORESET for the first terminal is obtained based on information about the basic CORESET.

13. In the basic CORESET, a first PDCCH candidate for the first terminal is defined separately from a second PDCCH candidate for the second terminal; The first terminal according to claim 2 , characterized in that the communication module is configured to monitor the first PDCCH candidate in the basic CORESET.

14. A method for operating a reduced capability first terminal (reduced capability UE) in a wireless communication system, comprising: receiving configuration information for configuring a first downlink bandwidth part (DL BWP) and a first uplink bandwidth part (Uplink BWP) used in an initial access procedure; receiving an indicator indicating BWP access barring of the first terminal in a second UL BWP and a second DL BWP for a second terminal of a legacy type; and performing an initial access procedure on 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; The first UL BWP and the second UL BWP are set individually, The initial access procedure includes a random access procedure, The first UL BWP includes first resources for the optional connection procedure of the first terminal; The method, wherein the first resource is identical to a second resource for an optional connection procedure on a second UL BWP of the second terminal.

15. The method of claim 14, further comprising obtaining information regarding a control resource set (CORESET) from a second synchronization signal block (SSB) related to the second terminal.

16. 16. The method of claim 15, further comprising receiving information about a CORESET for the first terminal, the CORESET being defined separately from the CORESET for the second terminal, using a system information block 1 (SIB1).

17. receiving an SIB1 for the second terminal; The method according to claim 15, wherein the SIB1 includes scheduling information related to system information for performing the initial access procedure of the first terminal.

18. The method of claim 17, wherein the scheduling information includes information regarding a start physical resource block (PRB) of the first DL BWP activated for performing an initial access procedure of the first terminal.

19. receiving an SIB1 for the second terminal; The method according to claim 15, characterized in that the SIB1 includes configuration information for an optional access procedure for an initial access of the first terminal.

20. 15. The method of claim 14, further comprising obtaining information regarding a CORESET for the first terminal from a first SSB defined separately from a second SSB for the second terminal.

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