Method and device for prach transmission in SBFD subband

Abstract

A method and a device for PRACH transmission in an SBFD subband are disclosed. The method of a user equipment (UE) comprises the steps of: measuring a signal received from a base station; selecting one random access channel (RACH) occasion (RO) between a legacy RO and an additional RO on the basis of measured reference signal received power (RSRP) of the signal satisfying an RSRP threshold; and transmitting a random access (RA) preamble to the base station in the one RO.

Description

Method and device for PRACH transmission in SBFD subband

[0001] The present disclosure relates to improved communication technology, and more particularly, to technology for transmitting a physical random access channel (PRACH) in a subband full duplex (SBFD) subband.

[0002] Communication networks (e.g., 5G communication networks, 6G communication networks, etc.) are being developed to provide improved communication services compared to existing communication networks (e.g., long term evolution (LTE), advanced LTE-A (LTE-A), etc.). 5G communication networks (e.g., new radio (NR) communication networks) can support frequency bands above 6 GHz as well as frequency bands below 6 GHz. That is, 5G communication networks can support FR1 bands and / or FR2 bands. 5G communication networks can support various communication services and scenarios compared to LTE communication networks. For example, usage scenarios of 5G communication networks can include enhanced Mobile Broadband (eMBB), Ultra Reliable Low Latency Communication (URLLC), massive Machine Type Communication (mMTC), etc.

[0003] Compared to 5G, 6G communication networks can support a wider range of communication services and scenarios. 6G communication networks can meet requirements for ultra-high performance, ultra-high bandwidth, ultra-high space, ultra-high precision, ultra-intelligence, and / or ultra-reliability. 6G communication networks can support diverse and wide frequency bands and be applied to various usage scenarios (e.g., terrestrial communications, non-terrestrial communications, sidelink communications, etc.).

[0004] Meanwhile, a communication network may support subband full duplex (SBFD) operation. In a communication network supporting SBFD operation, an uplink (UL) subband may be configured in a downlink (DL) section. A terminal may perform uplink transmission in a UL subband configured in the DL section and / or in a UL region (e.g., UL resource) other than the SBFD resource. If the uplink transmission power in the UL subband and the uplink transmission power in the UL region are controlled based on the same method, problems such as increased interference caused by uplink transmission and deterioration of reception performance of uplink transmission may occur. A method for controlling uplink transmission power to solve the above-described problems may be needed.

[0005] The purpose of the present disclosure to solve the above problems is to provide a method and device for PRACH (physical random access channel) transmission in a subband full duplex (SBFD) subband.

[0006] According to embodiments of the present disclosure for achieving the above object, a method of a UE (user equipment) includes: measuring a signal received from a base station; selecting one RO type from among N-SBFD (non-subband full duplex) RO (RACH (random access channel) occasion) and SBFD RO based on whether the measured RSRP (reference signal received power) of the signal satisfies an RSRP threshold; and transmitting an RA (random access) preamble to the base station in at least one RO among a plurality of ROs corresponding to the one RO type.

[0007] The method of the UE may further include: selecting another RO type from among the N-SBFD RO and the SBFD RO based on the measured RSRP not satisfying the RSRP threshold; and transmitting the RA preamble to the base station in at least one RO from among a plurality of ROs corresponding to the other RO type.

[0008] Each of the one RO type and the other RO type may be the SBFD RO and the N-SBFD RO, or each of the one RO type and the other RO type may be the N-SBFD RO and the SBFD RO.

[0009] The method of the UE may further include a step of receiving information of the RSRP threshold from the base station, wherein the RSRP threshold may be set for selection of an RO type for transmission of the RA preamble.

[0010] Based on the fact that the RO type to which the RA preamble is transmitted is not indicated by the base station, the UE may select one of the N-SBFD RO and the SBFD RO based on a comparison result between the measured RSRP and the RSRP threshold.

[0011] The operation of selecting the one RO based on the comparison result between the measured RSRP and the RSRP threshold by the UE may be performed in an RA procedure other than an RA procedure initiated by a physical downlink control channel (PDCCH) order transmitted by the base station.

[0012] The step of transmitting the RA preamble to the base station may include the step of repeatedly transmitting the RA preamble to the base station in ROs a number of repetitions associated with the RSRP repetition threshold based on the measured RSRP satisfying the RSRP repetition threshold, wherein the RSRP repetition threshold may be independently set for each of the N-SBFD RO and the SBFD RO.

[0013] The above N-SBFD RO can be set in N-SBFD resources, the above SBFD RO is set in SBFD resources, and the UE can support SBFD operation.

[0014] According to embodiments of the present disclosure for achieving the above object, a method of a base station includes the steps of transmitting configuration information of an N-SBFD (non-subband full duplex) RO (RACH (random access channel) occasion) and configuration information of an SBFD RO to a UE (user equipment); transmitting information of an RSRP (reference signal received power) threshold used to select an RO type for transmission of an RA (random access) preamble to the UE; transmitting a signal to the UE; and receiving the RA preamble from the UE in at least one of a plurality of ROs corresponding to an RO type selected based on a comparison result of a measured RSRP of the signal and the RSRP threshold, wherein the RO corresponding to the RO type is the N-SBFD RO or the SBFD RO.

[0015] One RO type among the N-SBFD RO and the SBFD RO may be selected based on whether the measured RSRP satisfies the RSRP threshold, and another RO type among the N-SBFD RO and the SBFD RO may be selected based on whether the measured RSRP does not satisfy the RSRP threshold.

[0016] Each of the one RO type and the other RO type may be the SBFD RO and the N-SBFD RO, or each of the one RO type and the other RO type may be the N-SBFD RO and the SBFD RO.

[0017] Based on the RO type for which the RA preamble is transmitted being not indicated by the base station, the RO type for transmission of the RA preamble may be selected based on a comparison result between the measured RSRP and the RSRP threshold.

[0018] In an RA procedure other than an RA procedure initiated by a PDCCH (physical downlink control channel) order transmitted by the base station, the RO type for transmission of the RA preamble may be selected based on a comparison result between the measured RSRP and the RSRP threshold.

[0019] The above N-SBFD RO can be set in N-SBFD (non-subband full duplex) resources, the above SBFD RO can be set in SBFD resources, and the UE can support SBFD operation.

[0020] According to embodiments of the present disclosure for achieving the above object, a user equipment (UE) includes at least one processor, wherein the at least one processor causes the UE to measure a signal received from a base station; select one RO type from among non-subband full duplex (N-SBFD) RO (RACH (random access channel) occasion) and SBFD RO based on whether the measured RSRP (reference signal received power) of the signal satisfies an RSRP threshold; and transmit an RA (random access) preamble to the base station in at least one RO among a plurality of ROs corresponding to the one RO type.

[0021] The at least one processor may further cause the UE to select another RO type among the N-SBFD RO and the SBFD RO based on the measured RSRP not satisfying the RSRP threshold; and transmit the RA preamble to the base station in at least one RO among the plurality of ROs corresponding to the other RO type.

[0022] The at least one processor may further cause the UE to receive information of the RSRP threshold from the base station, wherein the RSRP threshold may be set for selection of an RO type for transmission of the RA preamble.

[0023] Based on the fact that the RO type to which the RA preamble is transmitted is not indicated by the base station, the UE may select one of the N-SBFD RO and the SBFD RO based on a comparison result between the measured RSRP and the RSRP threshold.

[0024] The operation of selecting the one RO based on the comparison result between the measured RSRP and the RSRP threshold by the UE may be performed in an RA procedure other than an RA procedure initiated by a physical downlink control channel (PDCCH) order transmitted by the base station.

[0025] To transmit the RA preamble to the base station, the at least one processor may cause the UE to repeatedly transmit the RA preamble to the base station in ROs a number of repetitions associated with the RSRP repetition threshold based on the measured RSRP satisfying an RSRP repetition threshold, wherein the RSRP repetition threshold may be independently set for each of the N-SBFD RO and the SBFD RO.

[0026] According to the present disclosure, a terminal can transmit an RA (random access) preamble in a legacy RO (RACH (random access channel) occasion) or an additional RO. The terminal can select an RO type (e.g., legacy RO or additional RO) based on a comparison result between a measurement result of a signal received from a base station (e.g., reference signal received power (RSRP)) and an RSRP threshold, and can transmit an RA preamble to the base station in an RO corresponding to the selected RO type. According to the above-described operation, ambiguity regarding selection of an RO type for transmission of an RA preamble can be resolved. Therefore, in a communication system supporting subband full duplex (SBFD), the RA procedure can be efficiently performed, and the performance of the communication system can be improved.

[0027] Figure 1 is a conceptual diagram illustrating embodiments of a communication system.

[0028] Figure 2 is a block diagram illustrating embodiments of communication nodes constituting a communication system.

[0029] Figure 3 is a block diagram illustrating embodiments of communication nodes that perform communication.

[0030] Figure 4a is a block diagram illustrating embodiments of a transmission path.

[0031] Figure 4b is a block diagram illustrating embodiments of a receiving path.

[0032] Figure 5 is a conceptual diagram illustrating embodiments of system frames in a communication system.

[0033] Figure 6 is a conceptual diagram illustrating embodiments of subframes in a communication system.

[0034] Figure 7 is a conceptual diagram illustrating embodiments of slots in a communication system.

[0035] Figure 8 is a conceptual diagram illustrating embodiments of time-frequency resources in a communication system.

[0036] Figure 9 is a conceptual diagram illustrating the retransmission operation of an RA preamble in an SBFD terminal.

[0037] Figure 10 is a conceptual diagram illustrating an unfair problem between an SBFD terminal and a legacy terminal in the transmission of an RA preamble.

[0038] Figure 11 is a conceptual diagram illustrating the configuration of preamble subgroups.

[0039] Figure 12 is a conceptual diagram illustrating a (re)transmission procedure of an RA preamble based on proposal #5-1.

[0040] Figure 13 is a conceptual diagram illustrating a (re)transmission procedure of an RA preamble based on proposal #5-2.

[0041] Figure 14 is a conceptual diagram illustrating a (re)transmission procedure of an RA preamble based on proposal #5-3.

[0042] Figure 15 is a conceptual diagram illustrating the (re)transmission procedure of an RA preamble based on proposal #5-4.

[0043] This disclosure may be subject to various modifications and various embodiments. Specific embodiments are illustrated and described in detail in the drawings. However, this is not intended to limit the disclosure to specific embodiments, but rather to encompass all modifications, equivalents, and alternatives falling within the spirit and technical scope of the disclosure.

[0044] While terms such as "first" and "second" may be used to describe various components, these components should not be limited by these terms. These terms are used solely to distinguish one component from another. For example, without departing from the scope of the present disclosure, a first component could be referred to as a "second component," and similarly, a second component could also be referred to as a "first component." The term "and / or" may refer to a combination of multiple related items described herein or to any of multiple related items described herein.

[0045] In the present disclosure, “at least one of A and B” may mean “at least one of A or B” or “at least one of combinations of one or more of A and B.” Additionally, in the present disclosure, “at least one of A and B” may mean “at least one of A or B” or “at least one of combinations of one or more of A and B.”

[0046] In the present disclosure, (re)transmission may mean “transmission,” “retransmission,” or “transmission and retransmission,” (re)setting may mean “setting,” “resetting,” or “setting and resetting,” (re)connection may mean “connection,” “reconnection,” or “connection and reconnection,” and (re)connection may mean “connection,” “reconnection,” or “connection and reconnection.”

[0047] When a component is referred to as being "connected" or "connected" to another component, it should be understood that it may be directly connected or connected to that other component, but that there may be other components intervening. Conversely, when a component is referred to as being "directly connected" or "connected" to another component, it should be understood that there are no other components intervening.

[0048] The terminology used in this disclosure is only used to describe specific embodiments and is not intended to limit the present disclosure. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this disclosure, it should be understood that the terms "comprises" or "has" indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0049] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which this disclosure pertains. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and shall not be interpreted in an idealized or overly formal sense unless explicitly defined herein.

[0050] Hereinafter, preferred embodiments of the present disclosure will be described in more detail with reference to the attached drawings. In order to facilitate an overall understanding in describing the present disclosure, the same reference numerals will be used for identical components in the drawings, and redundant descriptions of identical components will be omitted. In addition to the embodiments explicitly described in the present disclosure, operations may be performed according to combinations of embodiments, extensions of embodiments, and / or modifications of embodiments. The performance of some operations may be omitted, and the order of operation may be changed.

[0051] In an embodiment, even if a method (e.g., transmitting or receiving a signal) performed by a first communication node among communication nodes is described, a corresponding second communication node can perform a method (e.g., receiving or transmitting a signal) corresponding to the method performed by the first communication node. That is, if an operation of a UE (user equipment) is described, a corresponding base station can perform an operation corresponding to the operation of the UE. Conversely, if an operation of a base station is described, a corresponding UE can perform an operation corresponding to the operation of the base station.

[0052] A base station may be referred to as a NodeB, an evolved NodeB, a gNodeB (next generation node B), a gNB, a device, an apparatus, a node, a communication node, a BTS (base transceiver station), a RRH (radio remote head), a TRP (transmission reception point), a RU (radio unit), an RSU (road side unit), a radio transceiver, an access point, an access node, etc. A UE may be referred to as a terminal, a device, an apparatus, a node, a communication node, an end node, an access terminal, a mobile terminal, a station, a subscriber station, a mobile station, a portable subscriber station, an OBU (on-broad unit), etc.

[0053] In the present disclosure, signaling may be at least one of upper layer signaling, MAC signaling, or PHY (physical) signaling. A message used for upper layer signaling may be referred to as an "upper layer message" or an "upper layer signaling message." A message used for MAC signaling may be referred to as a "MAC message" or a "MAC signaling message." A message used for PHY signaling may be referred to as a "PHY message" or a "PHY signaling message." Upper layer signaling may refer to a transmission and reception operation of system information (e.g., a master information block (MIB), a system information block (SIB)) and / or a radio resource control (RRC) message. MAC signaling may refer to a transmission and reception operation of a MAC control element (CE). PHY signaling may refer to a transmission and reception operation of control information (e.g., downlink control information (DCI), uplink control information (UCI), sidelink control information (SCI)).

[0054] In the present disclosure, “an operation (e.g., a transmission operation) is set” may mean that “setting information for the operation (e.g., an information element, a parameter)” and / or “information instructing the performance of the operation” is signaled. “An information element (e.g., a parameter) is set” may mean that the information element is signaled. In the present disclosure, “signal and / or channel” may mean a signal, a channel, or “signal and channel,” and “signal” may be used to mean “signal and / or channel.” In the present disclosure, time and time point may be used interchangeably. Time may be interpreted as either time or time point depending on the context, and time point may be interpreted as either time or time point depending on the context.

[0055] In the present disclosure, a phrase including “if (e.g., when ~)” can be expressed as a phrase including “based on (e.g., based on ~)” or a phrase including “in response to (e.g., in response to ~)”. In other words, a phrase including “if ~)” can be interpreted as being identical or similar to a phrase including “based on” or a phrase including “in response to”.

[0056] The communication network to which the embodiment is applied is not limited to what is described below, and the embodiment may be applied to various communication networks (e.g., 4G communication networks, 5G communication networks, and / or 6G communication networks). Here, the communication network may be used in the same sense as the communication system.

[0057] Figure 1 is a conceptual diagram illustrating embodiments of a communication system.

[0058] Referring to FIG. 1, the communication system (100) may include a plurality of communication nodes (110-1, 110-2, 110-3, 120-1, 120-2, 130-1, 130-2, 130-3, 130-4, 130-5, 130-6). In addition, the communication system (100) may further include a core network (e.g., a serving-gateway (S-GW), a packet data network (PDN)-gateway (P-GW), a mobility management entity (MME)). If the communication system (100) is a 5G communication system (e.g., a new radio (NR) system), the core network may include an access and mobility management function (AMF), a user plane function (UPF), a session management function (SMF), etc.

[0059] A plurality of communication nodes (110 to 130) can support a communication protocol (e.g., LTE communication protocol, LTE-A communication protocol, NR communication protocol, etc.) specified in the 3GPP (3rd generation partnership project) standard. The plurality of communication nodes (110 to 130) may support CDMA (code division multiple access) technology, WCDMA (wideband CDMA) technology, TDMA (time division multiple access) technology, FDMA (frequency division multiple access) technology, OFDM (orthogonal frequency division multiplexing) technology, Filtered OFDM technology, CP (cyclic prefix)-OFDM technology, DFT-s-OFDM (discrete Fourier transform-spread-OFDM) technology, OFDMA (orthogonal frequency division multiple access) technology, SC (single carrier)-FDMA technology, NOMA (non-orthogonal multiple access) technology, GFDM (generalized frequency division multiplexing) technology, FBMC (filter bank multi-carrier) technology, UFMC (universal filtered multi-carrier) technology, SDMA (space division multiple access) technology, etc. Each of the plurality of communication nodes may have the following structure.

[0060] Figure 2 is a block diagram illustrating embodiments of communication nodes constituting a communication system.

[0061] Referring to FIG. 2, a communication node (200) may include at least one processor (210), a memory (220), and a transmission / reception device (230) that is connected to a network and performs communication. In addition, the communication node (200) may further include an input interface device (240), an output interface device (250), a storage device (260), etc. Each component included in the communication node (200) may be connected by a bus (270) and communicate with each other.

[0062] The processor (210) can execute program commands stored in at least one of the memory (220) and the storage device (260). The processor (210) may refer to a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor in which the methods according to embodiments of the present disclosure are performed. Each of the memory (220) and the storage device (260) may be configured with at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory (220) may be configured with at least one of a read-only memory (ROM) and a random access memory (RAM).

[0063] Referring again to FIG. 1, the communication system (100) may include a plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) and a plurality of terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6). Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) may form a macro cell. Each of the fourth base station (120-1) and the fifth base station (120-2) may form a small cell. The fourth base station (120-1), the third terminal (130-3), and the fourth terminal (130-4) may be within the cell coverage of the first base station (110-1). The second terminal (130-2), the fourth terminal (130-4), and the fifth terminal (130-5) may be within the cell coverage of the second base station (110-2). The fifth base station (120-2), the fourth terminal (130-4), the fifth terminal (130-5), and the sixth terminal (130-6) may be within the cell coverage of the third base station (110-3). The first terminal (130-1) may be within the cell coverage of the fourth base station (120-1). The sixth terminal (130-6) may be within the cell coverage of the fifth base station (120-2).

[0064] Here, each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may be referred to as a NodeB (NB), an evolved NodeB (eNB), a gNB, an advanced base station (ABS), a high reliability-base station (HR-BS), a base transceiver station (BTS), a radio base station, a radio transceiver, an access point, an access node, a radio access station (RAS), a mobile multihop relay-base station (MMR-BS), a relay station (RS), an advanced relay station (ARS), a high reliability-relay station (HR-RS), a home NodeB (HNB), a home eNodeB (HeNB), a road side unit (RSU), a radio remote head (RRH), a transmission point (TP), a transmission and reception point (TRP), etc.

[0065] Each of the plurality of terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) may be referred to as a user equipment (UE), terminal equipment (TE), advanced mobile station (AMS), high reliability-mobile station (HR-MS), terminal, access terminal, mobile terminal, station, subscriber station, mobile station, portable subscriber station, node, device, on board unit (OBU), etc.

[0066] Meanwhile, each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may operate in a different frequency band or may operate in the same frequency band. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may be connected to each other via an ideal backhaul link or a non-ideal backhaul link, and may exchange information with each other via the ideal backhaul link or the non-ideal backhaul link. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may be connected to the core network via the ideal backhaul link or the non-ideal backhaul link. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) can transmit a signal received from the core network to the corresponding terminal (130-1, 130-2, 130-3, 130-4, 130-5, 130-6), and can transmit a signal received from the corresponding terminal (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) to the core network.

[0067] Additionally, each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may support MIMO transmission (e.g., single user (SU)-MIMO, multi user (MU)-MIMO, massive MIMO, etc.), coordinated multipoint (CoMP) transmission, carrier aggregation (CA) transmission, transmission in an unlicensed band, sidelink communication (e.g., device to device communication (D2D), proximity services (ProSe)), Internet of Things (IoT) communication, dual connectivity (DC), etc. Here, each of the plurality of terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) can perform an operation corresponding to the base station (110-1, 110-2, 110-3, 120-1, 120-2) and an operation supported by the base station (110-1, 110-2, 110-3, 120-1, 120-2). For example, the second base station (110-2) can transmit a signal to the fourth terminal (130-4) based on the SU-MIMO scheme, and the fourth terminal (130-4) can receive a signal from the second base station (110-2) by the SU-MIMO scheme. Alternatively, the second base station (110-2) can transmit signals to the fourth terminal (130-4) and the fifth terminal (130-5) based on the MU-MIMO method, and each of the fourth terminal (130-4) and the fifth terminal (130-5) can receive signals from the second base station (110-2) based on the MU-MIMO method.

[0068] Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) can transmit a signal to the fourth terminal (130-4) based on the CoMP scheme, and the fourth terminal (130-4) can receive a signal from the first base station (110-1), the second base station (110-2), and the third base station (110-3) based on the CoMP scheme. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) can transmit and receive a signal with terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) within its cell coverage based on the CA scheme. Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) can control sidelink communication between the fourth terminal (130-4) and the fifth terminal (130-5), and each of the fourth terminal (130-4) and the fifth terminal (130-5) can perform sidelink communication under the control of the second base station (110-2) and the third base station (110-3), respectively.

[0069] Meanwhile, communication nodes performing communication in a communication network may be configured as follows. The communication node illustrated in Fig. 3 may be a specific embodiment of the communication node illustrated in Fig. 2.

[0070] Figure 3 is a block diagram illustrating embodiments of communication nodes that perform communication.

[0071] Referring to FIG. 3, each of the first communication node (300a) and the second communication node (300b) may be a base station or a UE. The first communication node (300a) may transmit a signal to the second communication node (300b). The transmission processor (311) included in the first communication node (300a) may receive data (e.g., a data unit) from a data source (310). The transmission processor (311) may receive control information from the controller (316). The control information may include at least one of system information, RRC configuration information (e.g., information configured by RRC signaling), MAC control information (e.g., MAC CE), or PHY control information (e.g., DCI, SCI).

[0072] The transmitting processor (311) may perform a processing operation on data (e.g., an encoding operation, a symbol mapping operation, etc.) to generate data symbol(s). The transmitting processor (311) may perform a processing operation on control information (e.g., an encoding operation, a symbol mapping operation, etc.) to generate control symbol(s). In addition, the transmitting processor (311) may generate synchronization / reference symbol(s) for a synchronization signal and / or a reference signal.

[0073] The Tx MIMO processor (312) may perform a spatial processing operation (e.g., a precoding operation) on data symbol(s), control symbol(s), and / or synchronization / reference symbol(s). The output (e.g., a symbol stream) of the Tx MIMO processor (312) may be provided to modulators (MODs) included in the transceivers (313a to 313t). The modulators (MODs) may perform a processing operation on the symbol stream to generate modulation symbols, and may perform an additional processing operation (e.g., an analog conversion operation, an amplification operation, a filtering operation, an upconversion operation) on the modulation symbols to generate signals. The signals generated by the modulators (MODs) of the transceivers (313a to 313t) may be transmitted via the antennas (314a to 314t).

[0074] Signals transmitted by the first communication node (300a) may be received by antennas (364a to 364r) of the second communication node (300b). Signals received by the antennas (364a to 364r) may be provided to demodulators (DEMODs) included in transceivers (363a to 363r). The demodulator (DEMOD) may perform a processing operation (e.g., a filtering operation, an amplification operation, a downconversion operation, a digital conversion operation) on the signal to obtain samples. The demodulator (DEMOD) may perform an additional processing operation on the samples to obtain symbols. The MIMO detector (362) may perform a MIMO detection operation on the symbols. The receiving processor (361) may perform a processing operation (e.g., a deinterleaving operation, a decoding operation) on the symbols. The output of the receiving processor (361) may be provided to a data sink (360) and a controller (366). For example, data may be provided to the data sink (360), and control information may be provided to the controller (366).

[0075] Meanwhile, the second communication node (300b) can transmit a signal to the first communication node (300a). The transmitting processor (368) included in the second communication node (300b) can receive data (e.g., data units) from a data source (367) and perform a processing operation on the data to generate data symbol(s). The transmitting processor (368) can receive control information from the controller (366) and perform a processing operation on the control information to generate control symbol(s). In addition, the transmitting processor (368) can perform a processing operation on a reference signal to generate reference symbol(s).

[0076] The Tx MIMO processor (369) may perform spatial processing operations (e.g., precoding operations) on data symbol(s), control symbol(s), and / or reference symbol(s). The output (e.g., symbol stream) of the Tx MIMO processor (369) may be provided to modulators (MODs) included in the transceivers (363a to 363t). The modulators (MODs) may perform processing operations on the symbol streams to generate modulation symbols, and may perform additional processing operations (e.g., analog conversion operations, amplification operations, filtering operations, upconversion operations) on the modulation symbols to generate signals. The signals generated by the modulators (MODs) of the transceivers (363a to 363t) may be transmitted via the antennas (364a to 364t).

[0077] Signals transmitted by the second communication node (300b) may be received by the antennas (314a to 314r) of the first communication node (300a). The signals received by the antennas (314a to 314r) may be provided to demodulators (DEMODs) included in the transceivers (313a to 313r). The demodulator (DEMOD) may perform a processing operation (e.g., a filtering operation, an amplification operation, a downconversion operation, a digital conversion operation) on the signal to obtain samples. The demodulator (DEMOD) may perform an additional processing operation on the samples to obtain symbols. The MIMO detector (320) may perform a MIMO detection operation on the symbols. The receiving processor (319) may perform a processing operation (e.g., a deinterleaving operation, a decoding operation) on the symbols. The output of the receiving processor (319) may be provided to a data sink (318) and a controller (316). For example, data may be provided to the data sink (318) and control information may be provided to the controller (316).

[0078] Memories (315 and 365) can store data, control information, and / or program code. Scheduler (317) can perform scheduling operations for communication. The processors (311, 312, 319, 361, 368, 369) and controllers (316, 366) illustrated in FIG. 3 may be the processor (210) illustrated in FIG. 2 and may be used to perform the methods described in the present disclosure.

[0079] FIG. 4a is a block diagram illustrating embodiments of a transmission path, and FIG. 4b is a block diagram illustrating embodiments of a reception path.

[0080] Referring to FIGS. 4A and 4B, a transmission path (410) may be implemented in a communication node that transmits a signal, and a reception path (420) may be implemented in a communication node that receives a signal. The transmission path (410) may include a channel coding and modulation block (411), an S-to-P (serial-to-parallel) block (512), an N IFFT (Inverse Fast Fourier Transform) block (413), a P-to-S (parallel-to-serial) block (414), a CP (cyclic prefix) addition block (415), and an UC (up-converter) (UC) (416). The receiving path (420) may include a DC (down-converter) (421), a CP removal block (422), an S-to-P block (423), an N FFT block (424), a P-to-S block (425), and a channel decoding and demodulation block (426). Here, N may be a natural number.

[0081] In the transmission path (410), information bits may be input to a channel coding and modulation block (411). The channel coding and modulation block (411) may perform a coding operation (e.g., a low-density parity check (LDPC) coding operation, a polar coding operation, etc.) and a modulation operation (e.g., a quadrature phase shift keying (QPSK), a quadrature amplitude modulation (QAM), etc.) on the information bits. The output of the channel coding and modulation block (411) may be a sequence of modulation symbols.

[0082] The S-to-P block (412) can convert modulation symbols in the frequency domain into parallel symbol streams to generate N parallel symbol streams. N can be an IFFT size or an FFT size. The N IFFT block (413) can perform an IFFT operation on the N parallel symbol streams to generate signals in the time domain. The P-to-S block (414) can convert the output (e.g., parallel signals) of the N IFFT block (413) into a serial signal to generate a serial signal.

[0083] The CP addition block (415) can insert a CP into a signal. The UC (416) can up-convert the frequency of the output of the CP addition block (415) to an RF (radio frequency) frequency. Additionally, the output of the CP addition block (415) can be filtered at the baseband before up-conversion.

[0084] A signal transmitted from a transmission path (410) may be input to a reception path (420). An operation in the reception path (420) may be the reverse operation of the operation in the transmission path (410). A DC (421) may down-convert the frequency of the received signal to a baseband frequency. A CP removal block (422) may remove a CP from a signal. The output of the CP removal block (422) may be a serial signal. An S-to-P block (423) may convert the serial signal into parallel signals. An N FFT block (424) may perform an FFT algorithm to generate N parallel signals. A P-to-S block (425) may convert the parallel signals into a sequence of modulation symbols. A channel decoding and demodulation block (426) may perform a demodulation operation on the modulation symbols and perform a decoding operation on the result of the demodulation operation to restore data.

[0085] In FIGS. 4A and 4B , Discrete Fourier Transform (DFT) and Inverse DFT (IDFT) may be used instead of FFT and IFFT. Each of the blocks (e.g., components) in FIGS. 4A and 4B may be implemented by at least one of hardware, software, or firmware. For example, some of the blocks in FIGS. 4A and 4B may be implemented by software, and the remaining blocks may be implemented by hardware or a “combination of hardware and software.” In FIGS. 4A and 4B , a block may be subdivided into multiple blocks, multiple blocks may be integrated into a single block, some blocks may be omitted, and blocks supporting other functions may be added.

[0086] Figure 5 is a conceptual diagram illustrating embodiments of a system frame in a communication system.

[0087] Referring to FIG. 5, time resources in a communication system can be divided into frame units. For example, system frames can be set consecutively in the time domain of the communication system. The length of a system frame can be 10 ms (milliseconds). The system frame number (SFN) can be set from #0 to #1023. In this case, 1024 system frames can be repeated in the time domain of the communication system. For example, the SFN of the system frame after system frame #1023 can be #0.

[0088] A system frame may include two half frames. A half frame may be 5 ms long. A half frame located at the beginning of the system frame may be referred to as "half frame #0," and a half frame located at the end of the system frame may be referred to as "half frame #1." A system frame may include 10 subframes. A subframe may be 1 ms long. The 10 subframes within a system frame may be referred to as "subframes #0-9."

[0089] Figure 6 is a conceptual diagram illustrating embodiments of subframes in a communication system.

[0090] Referring to FIG. 6, one subframe may include n slots, where n may be a natural number. Accordingly, one subframe may be composed of one or more slots.

[0091] Figure 7 is a conceptual diagram illustrating embodiments of slots in a communication system.

[0092] Referring to Figure 7, a single slot may include one or more symbols. A single slot illustrated in Figure 7 may include 14 symbols. The length of a slot may vary depending on the number and length of symbols contained in the slot. Alternatively, the length of a slot may vary depending on the numerology.

[0093] In a communication system, the numerology applied to physical signals and channels may be variable. The numerology may be variable to meet various technical requirements of the communication system. In a communication system applying CP (cyclic prefix)-based OFDM waveform technology, the numerology may include subcarrier spacing and CP length (or CP type). Table 1 may be a first embodiment of a method for configuring a numerology for a CP-OFDM-based communication system. At least some of the numerologies in Table 1 may be supported depending on the frequency band in which the communication system operates. In addition, the communication system may additionally support numerologies not listed in Table 1.

[0094]

[0095] When the subcarrier spacing is 15 kHz (e.g., μ=0), the slot length can be 1 ms. In this case, one system frame can contain 10 slots. When the subcarrier spacing is 30 kHz (e.g., μ=1), the slot length can be 0.5 ms. In this case, one system frame can contain 20 slots.

[0096] When the subcarrier spacing is 60 kHz (e.g., μ=2), the slot length can be 0.25 ms. In this case, one system frame can contain 40 slots. When the subcarrier spacing is 120 kHz (e.g., μ=3), the slot length can be 0.125 ms. In this case, one system frame can contain 80 slots. When the subcarrier spacing is 240 kHz (e.g., μ=4), the slot length can be 0.0625 ms. In this case, one system frame can contain 160 slots.

[0097] A symbol may be configured as a downlink (DL) symbol, a flexible (FL) symbol, or an uplink (UL) symbol. A slot consisting solely of DL symbols may be referred to as a "DL slot," a slot consisting solely of FL symbols may be referred to as an "FL slot," and a slot consisting solely of UL symbols may be referred to as a "UL slot."

[0098] The slot format can be semi-statically configured by higher layer signaling (e.g., RRC signaling). Information indicating the semi-static slot format can be included in the system information, and the semi-static slot format can be configured cell-specifically. In addition, the semi-static slot format can be additionally configured for each terminal through terminal-specific higher layer signaling (e.g., RRC signaling). The flexible symbol of the cell-specifically configured slot format can be overridden to a downlink symbol or an uplink symbol by terminal-specific higher layer signaling. In addition, the slot format can be dynamically indicated by physical layer signaling (e.g., a slot format indicator (SFI) included in DCI). The semi-statically configured slot format can be overridden by a dynamically indicated slot format. For example, the semi-statically configured flexible symbol can be overridden to a downlink symbol or an uplink symbol by the SFI.

[0099] The reference signal may be a channel state information-reference signal (CSI-RS), a sounding reference signal (SRS), a demodulation-reference signal (DM-RS), a phase tracking-reference signal (PT-RS), etc. The channel may be a physical broadcast channel (PBCH), a physical downlink control channel (PDCCH), a physical downlink shared channel (PDSCH), a physical uplink control channel (PUCCH), a physical uplink shared channel (PUSCH), a physical sidelink control channel (PSCCH), a physical sidelink shared channel (PSSCH), etc. In the present disclosure, a control channel may mean a PDCCH, a PUCCH, or a PSCCH, and a data channel may mean a PDSCH, a PUSCH, or a PSSCH.

[0100] Figure 8 is a conceptual diagram illustrating embodiments of time-frequency resources in a communication system.

[0101] Referring to FIG. 8, a resource consisting of one symbol (e.g., an OFDM symbol) in the time domain and one subcarrier in the frequency domain may be defined as a "RE (resource element)". Resources consisting of one OFDM symbol in the time domain and K subcarriers in the frequency domain may be defined as a "REG (resource element group)". A REG may include K REs. A REG may be used as a basic unit for resource allocation in the frequency domain. K may be a natural number. For example, K may be 12. N may be a natural number. In the slot illustrated in FIG. 7, N may be 14. N OFDM symbols may be used as a basic unit for resource allocation in the time domain.

[0102] In the present disclosure, RB may mean CRB (common RB). Alternatively, RB may mean PRB or VRB (virtual RB). In a communication system, CRB may mean RB that constitutes a set of consecutive RBs (e.g., a common RB grid) based on a reference frequency (e.g., point A). Carriers and / or bandwidth portions may be arranged on the common RB grid. That is, the carrier and / or bandwidth portions may be composed of CRB(s). RBs or CRBs that constitute the bandwidth portions may be referred to as PRBs, and within the bandwidth portions, the CRB index may be appropriately converted to the PRB index.

[0103] Downlink data can be transmitted via the PDSCH. The base station can transmit PDSCH configuration information (e.g., scheduling information) to the terminal via the PDCCH. The terminal can obtain the PDSCH configuration information by receiving the PDCCH (e.g., downlink control information (DCI)). For example, the PDSCH configuration information can include the MCS (modulation coding scheme) used for transmitting and receiving the PDSCH, time resource information of the PDSCH, frequency resource information of the PDSCH, feedback resource information for the PDSCH, etc. The PDSCH can refer to a radio resource through which downlink data is transmitted and received. Alternatively, the PDSCH can refer to the downlink data itself. The PDCCH can refer to a radio resource through which downlink control information (e.g., DCI) is transmitted and received. Alternatively, the PDCCH can refer to the downlink control information itself.

[0104] A terminal can perform a monitoring operation on the PDCCH to receive a PDSCH transmitted from a base station. The base station can inform the terminal of the configuration information for the PDCCH monitoring operation using a higher layer message (e.g., an RRC (radio resource control) message). The configuration information for the PDCCH monitoring operation can include CORESET (control resource set) information and search space information.

[0105] CORESET information may include PDCCH DMRS (demodulation reference signal) information, PDCCH precoding information, PDCCH occasion information, etc. The PDCCH DMRS may be a DMRS used to demodulate the PDCCH. The PDCCH occasion may be a region where the PDCCH can exist. That is, the PDCCH occasion may be a region where DCI can be transmitted. The PDCCH occasion may be referred to as a PDCCH candidate. The PDCCH occasion information may include time resource information and frequency resource information of the PDCCH occasion. In the time domain, the length of the PDCCH occasion may be indicated in symbol units. In the frequency domain, the size of the PDCCH occasion may be indicated in RB units (e.g., in PRB (physical resource block) units or CRB (common resource block) units).

[0106] The search space information may include a coreset identifier (ID) associated with the search space, a period of PDCCH monitoring, and / or an offset. Each of the PDCCH monitoring period and offset may be indicated on a slot-by-slot basis. In addition, the search space information may further include an index of the symbol at which the PDCCH monitoring operation begins.

[0107] A base station can configure a bandwidth part (BWP) for downlink communication. The BWP can be configured differently for each terminal. The base station can inform the terminal of the BWP configuration information using higher layer signaling. The higher layer signaling can mean "transmission operation of system information" and / or "transmission operation of RRC (radio resource control) message." The number of BWPs configured for one terminal can be one or more. The terminal can receive BWP configuration information from the base station and check the BWP(s) configured by the base station based on the BWP configuration information. When multiple BWPs are configured for downlink communication, the base station can activate one or more BWPs among the multiple BWPs. The base station can transmit the configuration information of the activated BWP(s) to the terminal using at least one of higher layer signaling, a medium access control (MAC) control element (CE), or DCI. The base station can perform downlink communication using the activated BWP(s). The terminal can identify the activated BWP(s) by receiving configuration information of the activated BWP(s) from the base station, and perform a downlink reception operation in the activated BWP(s).

[0108] Meanwhile, communication systems (e.g., NR communication systems, 5G communication systems, 6G communication systems) can support usage scenarios such as eMBB (enhanced Mobile Broadband), URLLC (Ultra Reliable Low Latency Communication), and mMTC (massive Machine Type Communication). Communication systems (e.g., communication networks) can support SBFD (subband full duplex) operation.

[0109] A communication system may support TDD (time division duplexing). In a communication system supporting TDD (hereinafter referred to as a "TDD communication system"), downlink (DL) symbol(s) and uplink (UL) symbol(s) may be configured in different time resources within a single carrier. DL and UL symbols may be associated with coverage and / or latency. In a TDD communication system, a base station can utilize resources more efficiently than in a frequency division duplexing (FDD) scheme by considering various use cases. Resource scheduling operations of the base station may be important in a TDD communication system. For improved TDD operation, SBFD operation (e.g., SBFD operation) may be supported. When SBFD operation is supported in a TDD communication system, DL communication (e.g., transmission and reception of DL signals) and UL communication (e.g., transmission and reception of UL signals) may be performed simultaneously within the same time resource. For example, within the same time resource, some subbands may be DL subbands, while other subbands may be UL subbands and / or FL subbands. In the present disclosure, a DL signal may be interpreted as a DL signal, a DL channel, or "a DL signal and a DL channel" depending on the context. In the present disclosure, a UL signal may be interpreted as a UL signal, an UL channel, or "a UL signal and a UL channel" depending on the context.

[0110] A symbol to which the SBFD operation is applied may be referred to as an SBFD symbol. A symbol to which the SBFD operation is not applied may be referred to as an N(non)-SBFD symbol. An N-SBFD symbol may be a DL symbol, an UL symbol, or an FL symbol. In an SBFD symbol, a terminal may perform DL communication and UL communication. In other words, in an SBFD symbol, a terminal may perform full duplex operation. A base station may assume that DL communication and UL communication are possible in an SBFD symbol. In an N-SBFD symbol, a terminal may perform one of DL communication and UL communication. In other words, in an N-SBFD symbol, a terminal may perform half duplex operation. An SBFD symbol may be a symbol including a subband on which an SBFD operation is performed. A subband for SBFD may be referred to or interpreted as a UL subband. A UL subband may be present (e.g., configured) within a symbol in which a synchronization signal block (SSB) is transmitted.

[0111] Resources (e.g., time resources and / or frequency resources) for SBFD operation can be configured in a semi-static manner. In other words, the configuration for SBFD resources can be a semi-static configuration. "The SBFD resource configuration being a semi-static configuration" can mean "the SBFD resource is configured by semi-static signaling (e.g., system information, RRC message)." In the present disclosure, SBFD resources can mean time resources and / or frequency resources for SBFD operation. A UL subband for SBFD can be an SBFD resource. Alternatively, SBFD resources can be configured in a dynamic manner. "The SBFD resource configuration being a dynamic configuration" can mean "the SBFD resource is configured by dynamic signaling (e.g., MAC CE, DCI, SCI)."

[0112] SBFD resources (e.g., UL subbands, SBFD symbols) can be configured within DL resources and / or FL (flexible) resources configured by TDD-UL-DL configuration common information (e.g., TDD-UL-DL-configCommon). The transition point from an N-SBFD symbol to an SBFD symbol in the time domain can be limited to one. The transition point from an SBFD symbol to an N-SBFD symbol in the time domain can be limited to one. With respect to resource configuration of a subband for SBFD, it may be desirable for a terminal to recognize resource configuration information of a subband for SBFD in advance.

[0113] The TDD-UL-DL configuration common information can be used to configure a pattern (e.g., TDD-UL-DL-Pattern) for DL ​​resources and / or UL resources in the time domain of a TDD communication system. The pattern for DL ​​resources and / or UL resources can be referred to as a UL / DL pattern. The UL / DL pattern can be changed according to the environment of the communication system (e.g., TDD communication system). Up to two UL / DL patterns can be configured for a terminal. The TDD-UL-DL configuration common information can be a cell-specific parameter (e.g., cell-specific configuration information). The base station can change the configuration (e.g., transmission direction, type) for symbol(s) for each terminal based on a specific slot within a preset UL / DL pattern. A slot for which the symbol configuration (e.g., symbol direction, symbol type) can be changed can be a slot configured as an FL resource by the TDD-UL-DL configuration common information. The symbol direction (e.g., symbol transmission direction) and / or symbol type may be DL, UL, or FL. The RRC signaling used to change the configuration of an FL slot (e.g., FL resource) may be TDD-UL-DL configuration dedicated information (e.g., TDD-UL-DL-ConfigDedicated). Table 2 may be TDD-UL-DL configuration common information, and Tables 3 and 4 may be TDD-UL-DL configuration dedicated information.

[0114]

[0115]

[0116]

[0117] The UL / DL pattern configured by the TDD-UL-DL configuration common information can be repeated according to a specific period (e.g., dl-UL-TransmissionPeriodicity). In the time period to which the UL / DL pattern is applied, the front region can be configured as a DL resource. In the time period to which the UL / DL pattern is applied, the rear region can be configured as a UL resource. In the time period to which the UL / DL pattern is applied, resources that are not configured as DL resources or UL resources can be FL resources. The period of the UL / DL pattern can vary depending on the reference numerology. A guard time (e.g., a guard gap) may be required for switching (e.g., transition) from a DL resource (e.g., a DL symbol / slot) to a UL resource (e.g., a UL symbol / slot). Since the propagation delay of DL signals causes interference to UL resources, a guard time may be required for switching from DL resources to UL resources. A separate guard time may not be required for switching from UL resources to DL resources. Since UL signals are transmitted based on the timing advance command (TAC) indicated by the base station, a guard time may not be required for switching from UL resources to DL resources.

[0118] TDD-UL-DL configuration common information (e.g., TDD-UL-DL-ConfigCommon) may be referred to as "TDD common" or "TDD common information". TDD-UL-DL configuration dedicated information (e.g., TDD-UL-DL-ConfigDedicated) may be referred to as "TDD dedicated" or "TDD dedicated information". A UL subband may mean a subband for SBFD. DL symbol(s) and / or DL ​​slot(s) may be referred to as a DL region (or DL ​​resource). UL symbol(s) and / or UL slot(s) may be referred to as a UL region (or UL resource). FL symbol(s) and / or FL slot(s) may be referred to as an FL region (or FL resource). A terminal that supports (e.g., recognizes) the SBFD operation may be referred to as an SBFD terminal or SBFD UE. A terminal that does not support (e.g., is not aware of) SBFD operation may be referred to as an N(non)-SBFD terminal or N-SBFD UE. An N-SBFD terminal may be a legacy terminal (e.g., a legacy UE). In the present disclosure, a terminal may be interpreted as an SBFD terminal and / or an N-SBFD terminal depending on the context. Legacy configuration (e.g., legacy information, legacy configuration information) may be information for an N-SBFD terminal.

[0119] The mapping rules between the RO (RACH (random access channel) occasion) and SSB where msg1 (message1) or msgA is transmitted and / or the method for setting the transmission power of msg1 or msgA will be described. Although the present disclosure will be described with a focus on msg1, the embodiments of the present disclosure can be applied not only to msg1 but also to msgA. In other words, the embodiments of the present disclosure can be applied to the 2-step RA procedure as well as the 4-step RA procedure. The methods, embodiments, proposals, and / or options proposed in the present disclosure can be applied independently. Alternatively, a combination of the methods(s), embodiments(s), proposals(s), and / or option(s) proposed in the present disclosure can be applied. The methods(s), embodiments(s), proposals(s), and / or option(s) proposed in the present disclosure can be applied regardless of the operating state of the terminal (e.g., RRC state). For example, a terminal in an RRC connected state, an RRC inactive state, or an RRC idle state can perform the method(s), embodiment(s), proposal(s), and / or option(s) proposed in the present disclosure. Although SSB is mentioned as a selection criterion for msg1 (e.g., RO of msg1) in the present disclosure, not only SSB but also other RS ​​(reference signal) (e.g., RS for measuring channel state, RS for measuring path loss) can be used as a selection criterion for msg1.

[0120] The RACH configuration for an SBFD terminal may be configured based on method #1 or method #2. In method #1 for RACH configuration, the RACH configuration for the SBFD terminal may be configured in a manner that inherits the RACH configuration for the N-SBFD terminal. In other words, in method #1, the RACH configuration for the SBFD terminal may not be configured independently from the RACH configuration for the N-SBFD terminal. RACH configuration information (e.g., some RACH configuration information) may be shared between the legacy RACH procedure and the SBFD RACH procedure. The legacy RACH procedure may be a RACH procedure performed in a legacy terminal that does not support SBFD operation (e.g., an N-SBFD terminal). In the legacy RACH procedure, the RA (random access) preamble may be transmitted in a legacy RO (RACH (random access channel) occasion) configured in the N-SBFD resource. The SBFD RACH procedure may be a RACH procedure performed in an SBFD terminal that supports SBFD operation. In the SBFD RACH procedure, the RA preamble may be transmitted in an SBFD resource-configured RO (e.g., an additional RO) and / or a legacy RO. The SBFD RACH procedure may be referred to as an additional RACH procedure.

[0121] In method #2 for RACH configuration, a RACH configuration for an SBFD terminal (e.g., an SBFD RACH procedure) can be configured independently from a RACH configuration for an N-SBFD terminal (e.g., a legacy RACH procedure). In method #2, the base station can generate a RACH configuration for an N-SBFD terminal and a RACH configuration for an SBFD terminal, respectively, and transmit the RACH configuration for the N-SBFD terminal and the RACH configuration for the SBFD terminal to the terminal. In the present disclosure, the RACH configuration for the N-SBFD terminal may be referred to as an N-SBFD RACH configuration or a legacy RACH configuration, and the RACH configuration for the SBFD terminal may be referred to as an SBFD RACH configuration or an additional RACH configuration. The RACH configuration may be interpreted as an N-SBFD RACH configuration or an SBFD RACH configuration depending on the context.

[0122] An SBFD terminal and / or an N-SBFD terminal can determine a valid RO capable of transmitting an RA preamble, and can transmit the RA preamble in a valid RO. An SBFD terminal can transmit an RA preamble in a legacy RO as well as an SBFD RO. An SBFD RO may refer to an RO configured in an SBFD symbol(s). An SBFD RO may be indicated by an SBFD RACH configuration. An SBFD RO may be referred to as an additional RO. A legacy RO (e.g., an N-SBFD RO) may refer to an RO configured in an N-SBFD symbol(s). An N-SBFD RO may be indicated by an N-SBFD RACH configuration. In this case, a fairness issue may arise between an N-SBFD terminal and an SBFD terminal depending on the transmission power configuration of the RA preamble.

[0123] Figure 9 is a conceptual diagram illustrating the retransmission operation of an RA preamble in an SBFD terminal.

[0124] Referring to FIG. 9, RO #1, RO #2, RO #3, and RO #4 may be mapped to SSB #1, SSB #2, SSB #3, and SSB #4, respectively. An SBFD terminal may select RO #4 mapped to SSB #4, and transmit an RA preamble in RO #4. ​​The RA preamble may be transmitted in RO #4 (e.g., SBFD RO) configured in an UL subband (e.g., SBFD resource, SBFD symbol(s)). If the base station does not receive the RA preamble and / or a transmission collision of the RA preamble occurs, the SBFD terminal may not receive a response (e.g., msg2 or msgB) to the RA preamble within the random access response (RAR) window. In this case, the SBFD terminal may retransmit the RA preamble in the next RO #4. RO #4, where the RA preamble is retransmitted, may be set to N-SBFD resources (e.g., N-SBFD symbol(s)). In other words, the RA preamble may be retransmitted in a legacy RO.

[0125] The SBFD terminal may increase the transmit power due to the failure in transmission of the RA preamble, and may retransmit the RA preamble in a legacy RO (e.g., RO #4) using the increased transmit power. In the above situation, the N-SBFD terminal (e.g., the legacy terminal) may first transmit the RA preamble in the legacy RO where the RA preamble of the SBFD terminal is retransmitted. In other words, the RA preamble of the SBFD terminal and the RA preamble of the N-SBFD terminal may be transmitted in the same RO. Since the transmit power for the RA preamble of the SBFD terminal is greater than the transmit power for the RA preamble of the N-SBFD terminal, the transmission of the RA preamble of the N-SBFD terminal may fail. An unfair competition-based RACH procedure may cause an equity issue between the SBFD terminal and the N-SBFD terminal.

[0126] Information (e.g., required parameters) required for an SBFD terminal to set the transmission power of an RA preamble, a signaling method of the required information, and / or an operation of the SBFD terminal based on the required information will be described.

[0127] Settings for power control

[0128] How to set the parameter(s) required for the SBFD RACH procedure will be described.

[0129] - Proposal #1: Preamble received target power

[0130] A terminal (e.g., an SBFD terminal and / or an N-SBFD terminal) can determine the transmission power for transmission of an RA preamble (e.g., an initial transmission) based on the following mathematical expression 1.

[0131]

[0132] may be the transmit power of the RA preamble. For example, may be the transmit power of the RA preamble in the active UL BWP (b) of the carrier (f) of the cell (c) within the transmission occasion (i). may be the maximum output power for a carrier (f) of a cell (c) within a transmission occasion (i). The maximum output power may be predefined in the technical specification. Alternatively, the maximum output power may be indicated to the terminal by signaling from the base station. The maximum output power for the legacy RACH procedure and the maximum output power for the SBFD RACH procedure may be set independently. Alternatively, the maximum output power for the legacy RACH procedure and the maximum output power for the SBFD RACH procedure may be the same.

[0133] may be the PRACH target reception power for the active UL BWP (b) of the carrier (f) of the cell (c). The PRACH target reception power may be determined based on the following mathematical expression 2.

[0134]

[0135] The preamble reception target power may be indicated by the base station. The preamble reception target power for the legacy RACH procedure and the preamble reception target power for the SBFD RACH procedure may be set independently. Alternatively, the preamble reception target power for the legacy RACH procedure and the preamble reception target power for the SBFD RACH procedure may be the same. can be predefined in technical specifications. may be a preamble power ramping counter. The initial value of the preamble power ramping counter may be 1. The preamble power ramping counter may be incremented by 1 for each retransmission of the RA preamble. The preamble power ramping counter for the legacy RACH procedure and the preamble power ramping counter for the SBFD RACH procedure may be independently controlled (e.g., managed). The power ramping step may be a power ramping step indicated by the base station (e.g., a preamble power ramping step). The power ramping step for the legacy RACH procedure and the power ramping step for the SBFD RACH procedure may be set independently. Alternatively, the power ramping step for the legacy RACH procedure and the power ramping step for the SBFD RACH procedure may be the same.

[0136] may be the path loss for the active UL BWP (b) of the carrier (f) of the cell (c). The path loss may be determined based on the following mathematical expression 3.

[0137]

[0138] may be a reference signal power indicated to the terminal by signaling from the base station. It may be RSRP (reference signal received power) measured at the upper layer of the terminal.

[0139] When an SBFD terminal performs uplink transmission in a UL subband, the uplink transmission may interfere with communication (e.g., downlink communication from a base station to an SBFD terminal or a legacy terminal (e.g., an N-SBFD terminal)) in a DL subband set in a frequency band adjacent to the UL subband. To solve the interference problem described above, the preamble reception target power required in the UL subband may be different from the preamble reception target power required in the UL region. In the present disclosure, the UL region may be a resource set in the N-SBFD symbol(s), and the UL region may be distinguished from the UL subband set in the SBFD symbol(s). The UL region may be referred to as a UL resource.

[0140] The base station can independently set the preamble reception target power for SBFD symbol(s) and the preamble reception target power for N-SBFD symbol(s), and can transmit information about the preamble reception target power for SBFD symbol(s) and information about the preamble reception target power for N-SBFD symbol(s) to the terminal through signaling. The terminal can receive information about the preamble reception target power for SBFD symbol(s) and information about the preamble reception target power for N-SBFD symbol(s) from the base station. The terminal can use the preamble reception target power for SBFD symbol(s) to determine the transmission power of the RA preamble in the SBFD RO, and can transmit the RA preamble in the SBFD RO using the determined transmission power. The terminal may use the preamble reception target power for the N-SBFD symbol(s) to determine the transmit power of the RA preamble in a legacy RO (e.g., N-SBFD RO), and transmit the RA preamble in the legacy RO using the determined transmit power.

[0141] The terminal can independently determine (e.g., control) the transmit power for initial transmission or retransmission of the RA preamble in the SBFD symbol(s) and the N-SBFD symbol(s) based on the preamble reception target power for the SBFD symbol(s) and the preamble reception target power for the N-SBFD symbol(s). The terminal can independently manage (e.g., control) the parameter(s) used to determine the transmit power of the RA preamble in each of the SBFD RO and the legacy RO. For example, the terminal can independently manage a preamble power ramping counter, a number of transmissions of the RA preamble, and / or a maximum number of transmissions of the RA preamble for each of the SBFD RO and the legacy RO.

[0142] The base station may provide additional parameter(s) (e.g., target preamble reception power for SBFD terminals, power offset value (e.g., ) etc.) can be transmitted to the terminal through signaling. In the present disclosure, signaling may mean at least one of SI signaling, RRC signaling, MAC CE signaling, or DCI signaling. A power offset value for the SBFD terminal (e.g., ) is indicated (e.g., set), the SBFD terminal can determine the transmission power of the RA preamble based on the following mathematical expression 4. In mathematical expression 4, may be the PRACH target reception power for the N-SBFD terminal (or SBFD terminal), may be a path loss measured based on SSB or CSI-RS.

[0143]

[0144] - Proposal #2: RSRP Threshold (SSB or CSI-RS)

[0145] The base station can transmit information about the RSRP threshold to the terminal through signaling. The terminal can receive information about the RSRP threshold from the base station. The terminal can select an RO mapped to an SSB or reference signal (e.g., CSI-RS) having an RSRP greater than or equal to the RSRP threshold, and transmit an RA preamble to the base station in the selected RO. For example, the terminal can perform a measurement operation on one or more SSBs, and select an SSB having an RSRP greater than or equal to the RSRP threshold from among the one or more SSBs. Alternatively, the terminal can perform a measurement operation on one or more reference signals, and select a reference signal having an RSRP greater than or equal to the RSRP threshold from among the one or more reference signals.

[0146] The RSRP threshold can be set to ensure transmission of the RA preamble using a beam with guaranteed reception performance. Therefore, the RSRP threshold for selecting a legacy RO and the RSRP threshold for selecting an SBFD RO may not be set independently. In this case, the SBFD terminal can select an SBFD RO mapped to an SSB or reference signal based on the RSRP threshold for selecting a legacy RO.

[0147] However, uplink transmission in the UL subband causes cross link interference (CLI), and if the same RSRP threshold is used in the legacy RACH procedure and the SBFD RACH procedure, the CLI may increase. The legacy RACH procedure may refer to a RACH procedure performed in N-SBFD resources. The SBFD RACH procedure may refer to a RACH procedure performed in SBFD resources. If the channel environment between the UE and the base station is good and / or the reception performance of the UE is good, it may be desirable to allow the UE to transmit the RA preamble. In view of the above, the base station may set a separate RSRP threshold for selecting the SBFD RO in the UE. In other words, the RSRP threshold for selecting the legacy RO and the RSRP threshold for selecting the SBFD RO may be set independently in the UE. The RSRP threshold for selecting the legacy RO may be different from the RSRP threshold for selecting the SBFD RO.

[0148] The RSRP threshold for selecting an SBFD RO may be referred to as RSRP threshold A. The RSRP threshold for selecting a legacy RO may be referred to as RSRP threshold B. The UE may first determine whether there is an SSB (or CSI-RS) satisfying the RSRP threshold A in the SBFD resource. If there is no SSB (or CSI-RS) with an RSRP greater than or equal to the RSRP threshold A in the SBFD resource, the UE may not transmit an RA preamble in the SBFD resource and may attempt to transmit an RA preamble in an N-SBFD resource (e.g., a legacy RO).

[0149] A base station can signal (e.g., configure) an RO type (e.g., legacy RO or SBFD RO) for an RA procedure to a terminal. A terminal (e.g., an SBFD terminal) can perform an RA procedure based on the RO type indicated by the base station. For example, if the RO type indicated by the base station is a legacy RO, the terminal (e.g., an SBFD terminal) can transmit an RA preamble in a legacy RO corresponding to the RO type (e.g., at least one legacy RO among a plurality of legacy ROs). If the RO type indicated by the base station is an SBFD RO, the terminal (e.g., an SBFD terminal) can transmit an RA preamble in an SBFD RO corresponding to the RO type (e.g., at least one SBFD RO among a plurality of SBFD ROs).

[0150] The RO type (e.g., legacy RO or SBFD RO) for the RA procedure may not be indicated to the UE. In other words, the base station may not indicate the RO type for the RA procedure to the UE. In this case, the UE may select the RO type based on an RSRP threshold preset by the base station. For example, the base station may transmit information on the RSRP threshold for selecting the RO type for transmitting the RA preamble (e.g., rsrp-ThresholdSBFD) to the UE through signaling (e.g., SI signaling, RRC signaling, MAC CE signaling, and / or PHY signaling). The UE may receive information on the RSRP threshold through signaling from the base station.

[0151] If an RO type for an RA procedure is not indicated to the terminal and an RSRP threshold for the RO type is set in the terminal, the terminal may select an RO type for the RA procedure based on the RSRP threshold. The terminal may measure a channel / signal (e.g., SSB, PL (pathloss) RS, and / or CSI-RS) received from a base station, and if a measurement result (e.g., measured RSRP) satisfies the RSRP threshold, the terminal may select an RO type for the RA procedure as an SBFD RO (e.g., an additional RO), and transmit an RA preamble to the base station in an SBFD RO corresponding to the selected RO type (e.g., at least one SBFD RO among a plurality of SBFD ROs). In other words, the terminal may set the RO type as an additional RO, and transmit an RA preamble to the base station in the additional RO. If the measurement result of the channel / signal (e.g., measured RSRP) does not satisfy the RSRP threshold, the terminal may select the RO type for the RA procedure as legacy RO, and transmit an RA preamble to the base station in a legacy RO corresponding to the selected RO type (e.g., at least one legacy RO among a plurality of legacy ROs). In other words, the terminal may set the RO type to legacy RO, and transmit an RA preamble to the base station in the legacy RO. The base station may receive the RA preamble from the terminal in an RO corresponding to the RO type selected by the terminal (e.g., a legacy RO or an additional RO).

[0152] The RSRP measured at the terminal may be an RSRP for RS (e.g., DL PL RS) for downlink path loss measurement. If the measurement result of the channel / signal (e.g., the measured RSRP) satisfies the RSRP threshold, it may mean that the measurement result is equal to or greater than the RSRP threshold. If the measurement result of the channel / signal (e.g., the measured RSRP) does not satisfy the RSRP threshold, it may mean that the measurement result is less than or below the RSRP threshold. Conversely, if the measurement result of the channel / signal (e.g., the measured RSRP) satisfies the RSRP threshold, it may mean that the measurement result is less than or below the RSRP threshold. If the measurement result of the channel / signal (e.g., the measured RSRP) does not satisfy the RSRP threshold, it may mean that the measurement result is equal to or greater than the RSRP threshold.

[0153] The operation of selecting an RO type for the above-described RA procedure may be performed when the RA procedure is not initiated by a PDCCH order. In other words, when the RA procedure is initiated by a PDCCH order transmitted from a base station, the terminal may not perform an operation of setting an RO type indicated by the base station and / or an operation of selecting an RO type based on a comparison result between a measured RSRP and an RSRP threshold. In an RA procedure other than an RA procedure initiated by a PDCCH order, the terminal may perform an operation of setting an RO type indicated by the base station and / or an operation of selecting an RO type based on a comparison result between a measured RSRP and an RSRP threshold.

[0154] Meanwhile, the limitation of uplink cell radius in TDD communication systems can be resolved by utilizing UL subbands. Repeated uplink transmissions may be required. To enable repeated uplink transmissions (e.g., repeated transmission of RA preambles), the base station can configure multiple RSRP thresholds for terminals (e.g., SBFD terminals and / or legacy terminals). Each of the multiple RSRP thresholds can be associated with each repeated transmission.

[0155] The RSRP threshold(s) for repeated transmission of the RA preamble in the legacy RO and the RSRP threshold(s) for repeated transmission of the RA preamble in the SBFD RO can be independently set. The RSRP threshold for repeated transmission of the RA preamble may be referred to as an RSRP repetition threshold. The base station can transmit information about the RSRP threshold(s) for repeated transmission of the RA preamble in the legacy RO and information about the RSRP threshold(s) for repeated transmission of the RA preamble in the SBFD RO to the terminal through signaling. The terminal can receive information about the RSRP threshold(s) for repeated transmission of the RA preamble in the legacy RO and information about the RSRP threshold(s) for repeated transmission of the RA preamble in the SBFD RO from the base station. The RSRP threshold(s) for repeated transmission of the RA preamble in the legacy RO may include a first RSRP threshold (e.g., the first RSRP repetition threshold) for two repeated transmissions of the RA preamble in the legacy RO, a second RSRP threshold (e.g., the second RSRP repetition threshold) for four repeated transmissions of the RA preamble in the legacy RO, and a third RSRP threshold (e.g., the third RSRP repetition threshold) for eight repeated transmissions of the RA preamble in the legacy RO. The RSRP threshold(s) for repeated transmission of the RA preamble in the SBFD RO may include a first RSRP threshold (e.g., the first RSRP repetition threshold) for two repeated transmissions of the RA preamble in the SBFD RO, a second RSRP threshold (e.g., the second RSRP repetition threshold) for four repeated transmissions of the RA preamble in the SBFD RO, and a third RSRP threshold (e.g., the third RSRP repetition threshold) for eight repeated transmissions of the RA preamble in the SBFD RO.

[0156] When repeated transmission of the RA preamble is configured in a legacy RO, the UE may repeatedly transmit the RA preamble in the selected legacy RO based on an RSRP threshold according to the number of repetition transmissions of the RA preamble (e.g., 2, 4, or 8). In other words, when a measured RSRP threshold for a channel / signal (e.g., SSB, reference signal) satisfies a certain RSRP repetition threshold, the UE may select as many legacy ROs as the number of repetitions (e.g., n) associated with the certain RSRP repetition threshold, and transmit the RA preamble to the base station in the n legacy ROs. n may be a natural number. For example, when the measured RSRP threshold for a channel / signal (e.g., SSB, reference signal) satisfies a first RSRP repetition threshold, the UE may repeatedly transmit the RA preamble in two legacy ROs associated with the channel / signal. When the measured RSRP threshold for a channel / signal (e.g., SSB, reference signal) satisfies a second RSRP repetition threshold, the terminal may repeatedly transmit an RA preamble in four legacy ROs associated with the channel / signal. When the measured RSRP threshold for a channel / signal (e.g., SSB, reference signal) satisfies a third RSRP repetition threshold, the terminal may repeatedly transmit an RA preamble in eight legacy ROs associated with the channel / signal. In the present disclosure, when the measured RSRP satisfies an RSRP threshold (e.g., RSRP repetition threshold), it may mean that the measured RSRP is equal to or greater than the RSRP threshold. Alternatively, when the measured RSRP satisfies an RSRP threshold (e.g., RSRP repetition threshold), it may mean that the measured RSRP is less than or equal to the RSRP threshold.

[0157] When the repeated transmission of the RA preamble is set in the SBFD RO, the UE can repeatedly transmit the RA preamble in the selected SBFD RO based on an RSRP threshold according to the number of repetition transmissions of the RA preamble (e.g., 2, 4, or 8). In other words, when a measured RSRP threshold for a channel / signal (e.g., SSB, reference signal) satisfies a certain RSRP repetition threshold, the UE can select as many SBFD ROs as the number of repetitions (e.g., n) associated with the certain RSRP repetition threshold, and transmit the RA preamble to the base station in the n SBFD ROs. n can be a natural number. For example, when the measured RSRP threshold for a channel / signal (e.g., SSB, reference signal) satisfies a first RSRP repetition threshold, the UE can repeatedly transmit the RA preamble in two SBFD ROs associated with the channel / signal. If the measured RSRP threshold for a channel / signal (e.g., SSB, reference signal) satisfies the second RSRP repetition threshold, the terminal may repeatedly transmit the RA preamble in four SBFD ROs associated with the channel / signal. If the measured RSRP threshold for a channel / signal (e.g., SSB, reference signal) satisfies the third RSRP repetition threshold, the terminal may repeatedly transmit the RA preamble in eight SBFD ROs associated with the channel / signal.

[0158] Alternatively, the RSRP threshold(s) for repeated transmission of the RA preamble in a legacy RO and the RSRP threshold(s) for repeated transmission of the RA preamble in a SBFD RO may be set identically. For example, the base station may transmit information of the common RSRP threshold(s) for repeated transmission of the RA preamble to the terminal through signaling. The terminal may receive information of the common RSRP threshold(s) for repeated transmission of the RA preamble through signaling from the base station. The terminal may repeatedly transmit the RA preamble in the selected legacy RO or SBFD RO based on the RSRP threshold according to the number of repeated transmissions of the RA preamble (e.g., 2, 4, or 8). In other words, if the measured RSRP threshold for a channel / signal (e.g., SSB, reference signal) satisfies a certain RSRP repetition threshold, the terminal can select as many ROs as the number of repetitions (e.g., n) associated with the certain RSRP repetition threshold, and transmit an RA preamble to the base station in the n ROs. n can be a natural number.

[0159] For example, if the measured RSRP threshold for a channel / signal (e.g., SSB, reference signal) satisfies a first RSRP repetition threshold, the terminal may repeatedly transmit the RA preamble in two ROs associated with the channel / signal (e.g., two ROs corresponding to the indicated RO type or the selected RO type). If the measured RSRP threshold for a channel / signal (e.g., SSB, reference signal) satisfies a second RSRP repetition threshold, the terminal may repeatedly transmit the RA preamble in four ROs associated with the channel / signal (e.g., four ROs corresponding to the indicated RO type or the selected RO type). If the measured RSRP threshold for a channel / signal (e.g., SSB, reference signal) satisfies a third RSRP repetition threshold, the terminal may repeatedly transmit the RA preamble in eight ROs associated with the channel / signal (e.g., eight ROs corresponding to the indicated RO type or the selected RO type).

[0160] - Proposal #3: RA Preamble Group

[0161] SBFD terminals can transmit RA preambles in both SBFD ROs and legacy ROs. Legacy terminals, on the other hand, can only transmit RA preambles in legacy ROs. The space (or resource, probability) available for SBFD terminals to transmit RA preambles may be greater than the space (or resource, probability) available for legacy terminals to transmit RA preambles. If SBFD terminals transmit RA preambles in legacy ROs without any restrictions, fairness issues (e.g., unfairness issues) with respect to legacy terminals may arise.

[0162] Figure 10 is a conceptual diagram illustrating an unfair problem between an SBFD terminal and a legacy terminal in the transmission of an RA preamble.

[0163] Referring to FIG. 10, an SBFD terminal can transmit an RA preamble in a legacy RO as well as an SBFD RO. A legacy terminal cannot transmit an RA preamble in an SBFD RO and can only transmit an RA preamble in a legacy RO. The transmission opportunities of an RA preamble in an SBFD terminal may be greater than the transmission opportunities of an RA preamble in a legacy terminal. If an SBFD terminal performs a power ramping operation when retransmitting an RA preamble regardless of the RO type (e.g., SBFD RO, legacy RO), the unfairness problem for the legacy terminal may be further aggravated. To solve the above problem, a restriction on the RA preamble transmission of an SBFD terminal in a legacy RO may be required.

[0164] ●Proposal #3A: The base station can set an RSRP threshold A (e.g., an RSRP threshold for selecting an SBFD RO) that has a higher value than an RSRP threshold B (e.g., an RSRP threshold for selecting a legacy RO), and can transmit information about the RSRP threshold B and information about the RSRP threshold A to the UE through signaling. The UE can receive information about the RSRP threshold B and information about the RSRP threshold A through signaling from the base station. According to the above-described setting, the probability that the SBFD UE transmits an RA preamble in the SBFD RO can be reduced.

[0165] ●Proposal #3B: A preamble group (e.g., RA preamble group) can be divided into a preamble subgroup for legacy terminals and a preamble subgroup for SBFD terminals.

[0166] Figure 11 is a conceptual diagram illustrating the configuration of preamble subgroups.

[0167] Referring to FIG. 11, the total preambles (e.g., RA preambles) available for a contention-based random access (CBRA) procedure may be divided into two preamble subgroups. The two preamble subgroups may include a legacy preamble subgroup containing preambles for legacy terminals and an SBFD preamble subgroup containing preambles for SBFD terminals. The number of preambles included in the legacy preamble subgroup may be the same as the number of preambles included in the SBFD preamble subgroup. Alternatively, the number of preambles included in the legacy preamble subgroup may be different from the number of preambles included in the SBFD preamble subgroup. For example, the number of preambles included in the legacy preamble subgroup may be greater than the number of preambles included in the SBFD preamble subgroup. The base station can transmit configuration information of the legacy preamble subgroup to the legacy terminal. The legacy terminal can perform the RA procedure using the preamble belonging to the legacy preamble subgroup. The base station can transmit configuration information of the SBFD preamble subgroup to the SBFD terminal. The SBFD terminal can perform the RA procedure using the preamble belonging to the SBFD preamble subgroup.

[0168] Alternatively, all preambles available for the CBRA procedure (e.g., all RA preambles) can be configured for legacy terminals. In other words, a legacy terminal can perform the RA procedure using one preamble among all preambles available for the CBRA procedure. A preamble subgroup consisting of some preambles among all preambles available for the CBRA procedure can be configured. The base station can transmit configuration information of the preamble subgroup to a terminal (e.g., an SBFD terminal) through signaling. The SBFD terminal can perform the RA procedure using a preamble belonging to the preamble subgroup.

[0169] According to the above-described method, since the number of preambles (e.g., RA preambles) that a legacy terminal can select is greater than the number of preambles that an SBFD terminal can select, the collision probability of RA preambles in the legacy terminal may be lower than the collision probability of RA preambles in the SBFD terminal. Even if the legacy terminal is disadvantaged compared to the SBFD terminal in terms of transmission power, since the legacy terminal is advantageous compared to the SBFD terminal in terms of the collision probability of RA preambles, the above-described disadvantage may be offset or supplemented.

[0170] - Proposal #4: Combination of Proposal #2 (Independent RSRP Threshold) and Proposal #3 (RA Preamble Group)

[0171] Based on the above-described proposal #2, an RSRP threshold for selecting an SBFD RO and / or an RSRP threshold for selecting a legacy RO may be set. Based on the above-described proposal #3, a preamble subgroup for legacy terminals and / or a preamble subgroup for SBFD terminals may be set. Proposal #4 may be an embodiment based on a combination of Proposals #2 and #3.

[0172] If the channel environment between the SBFD terminal and the base station is not good, the SBFD terminal may transmit a preamble (e.g., an RA preamble) belonging to a preamble subgroup (e.g., a legacy preamble subgroup) in the legacy RO. The above-described operation of the SBFD terminal may be an unfair operation from the perspective of the legacy terminal.

[0173] If the measured RSRP is greater than or equal to the RSRP threshold, the SBFD terminal may select one preamble from among the preamble subgroup or all preambles shared with the legacy terminal and transmit the selected one preamble to the base station in an RO (e.g., an RO associated with the selected one preamble). If the measured RSRP is less than the RSRP threshold, the SBFD terminal may select one preamble from among the preamble subgroup configured for the SBFD terminal and transmit the selected one preamble to the base station. Alternatively, if the measured RSRP is greater than or equal to the RSRP threshold, the SBFD terminal may select one preamble from among the preamble subgroup configured for the SBFD terminal and transmit the selected one preamble to the base station. If the measured RSRP is less than the RSRP threshold, the SBFD terminal may select one preamble from among the preamble subgroup or all preambles shared with the legacy terminal, and transmit the selected one preamble to the base station in an RO (e.g., an RO associated with the selected one preamble).

[0174] In other words, the SBFD terminal may select one of the preamble subgroups based on the comparison result between the measured RSRP and the RSRP threshold, select one preamble within one preamble subgroup, and transmit the selected one preamble to the base station in an RO (e.g., an RO associated with the selected one preamble).

[0175] PRACH (re)transmission

[0176] If the transmission of msg1 (or msgA) fails, the terminal may attempt to retransmit msg1 after a preset time. The terminal may retransmit msg1 using increased transmission power or the same transmission power based on preset conditions. The terminal may perform a ramping operation of the transmission power for retransmitting msg1. The base station may transmit information on the maximum number of transmissions of msg1 (or msgA) to the terminal through signaling. The terminal may receive information on the maximum number of transmissions of msg1 (or msgA) from the base station. The terminal may retransmit msg1 up to the maximum number of transmissions set by the base station. If the transmission of msg1 is not successful within the maximum number of transmissions, the terminal may re-perform measurement for the RS, re-select an RO based on the measurement result of the RS, and transmit msg1 in the selected RO.

[0177] In a communication system, an SBFD operation may be introduced, and a terminal (e.g., an SBFD terminal) may transmit an RA preamble (e.g., msg1, msgA) to a base station not only in a legacy RO but also in an SBFD RO. If a retransmission procedure of an RA preamble is performed without any constraint on the transmission power of the RA preamble, unfairness to the legacy terminal may occur. For example, the SBFD terminal may retransmit the RA preamble in the legacy RO by applying power ramping, and since the transmission power of the RA preamble (e.g., the retransmitted RA preamble) transmitted by the SBFD terminal in the legacy RO is higher than the transmission power of the RA preamble (e.g., the initial RA preamble) transmitted by the legacy terminal in the legacy RO, the base station may not receive (e.g., detect) the RA preamble of the legacy terminal in the legacy RO.

[0178] To solve the above-described problem, a method for setting parameter(s) for retransmission of an RA preamble and / or a method for setting parameter(s) for determining transmission power in a retransmission procedure of an RA preamble may be required. The above-described parameter(s) may include at least one of a maximum number of transmissions of msg1, a transmission counter, a ramping step, or a ramping counter. The transmission counter may indicate the number of times actual transmission of msg1 has been performed. The ramping counter may indicate the number of times ramping has occurred. The method for setting the above-described parameter(s) and / or utilizing the above-described parameter(s) in a terminal may be based on the following proposal(s).

[0179] - Proposal #5: (Re)transmission procedure of RA preamble

[0180] Proposal #5-1: (Re)transmission procedure of RA preamble based on independent ramping steps and independent maximum transmission counts.

[0181] In the SBFD RACH procedure, the ramping step and the maximum number of transmissions, and in the legacy RACH procedure, the ramping step and the maximum number of transmissions can be independently set / managed. The base station can transmit the ramping step and the maximum number of transmissions for the SBFD RACH procedure to the terminal through signaling. The terminal can receive the ramping step and the maximum number of transmissions for the SBFD RACH procedure from the base station. The terminal can perform the SBFD RACH procedure based on the ramping step and the maximum number of transmissions indicated by the base station. The base station can transmit the ramping step and the maximum number of transmissions for the legacy RACH procedure to the terminal through signaling. The terminal can receive the ramping step and the maximum number of transmissions for the legacy RACH procedure from the base station. The terminal can perform the legacy RACH procedure based on the ramping step and the maximum number of transmissions indicated by the base station. The terminal can distinguish between RA preamble transmission in the SBFD RO and RA preamble transmission in the legacy RO. The base station can set the parameters for transmitting the RA preamble in the SBFD RO and the RA preamble in the legacy RO to the terminal through signaling. The terminal can perform the RA preamble transmission in the SBFD RO and the RA preamble transmission in the legacy RO based on the parameter(s) set by the base station. The RA preamble (re)transmission procedure based on Proposal #5-1 can be performed as follows.

[0182] Figure 12 is a conceptual diagram illustrating a (re)transmission procedure of an RA preamble based on proposal #5-1.

[0183] Referring to FIG. 12, the terminal may perform initialization for each of the SBFD RO and the legacy RO based on the number of initial transmissions. In other words, the terminal may set the transmission counter and the power ramping counter to initial values ​​(e.g., 0) in the SBFD RACH procedure, and may set the transmission counter and the power ramping counter to initial values ​​(e.g., 0) in the legacy RACH procedure. The terminal may increment the transmission counter and the power ramping counter based on the number of transmissions of msg1 (e.g., msg1 including the RA preamble) for each RO type (e.g., SBFD RO or legacy RO).

[0184] The maximum number of transmissions of msg1 (e.g., RA preamble) can be independently set for SBFD RO (e.g., SBFD RACH procedure) and legacy RO (e.g., legacy RACH procedure). The maximum number of transmissions of msg1 for SBFD RO and the maximum number of transmissions of msg1 for legacy RO can be set differently. The UE can independently check the number of transmissions of msg1 for each RO type. Regardless of the RO type, if the number of transmissions of msg1 exceeds the maximum number of transmissions, the UE can re-perform the channel / signal measurement operation and the RO selection operation based on the measurement result. In other words, if the number of transmissions of msg1 exceeds the maximum number of transmissions in at least one RACH procedure among the SBFD RACH procedure and the legacy RACH procedure, all RACH procedures, i.e., the SBFD RACH procedure and the legacy RACH procedure, can be initialized.

[0185] The ramping counter may be incremented if there is no change between the SSB (or CSI-RS) associated with the previous msg1 transmission and the SSB (or CSI-RS) associated with the current msg1 transmission, depending on the RO type. In other words, if the SSB (or CSI-RS) associated with the current msg1 transmission is the same as the SSB (or CSI-RS) associated with the previous msg1 transmission, the terminal may increment the ramping counter in the current msg1 transmission.

[0186] Alternatively, if the number of transmissions of msg1 in at least one RACH procedure among the SBFD RACH procedure and the legacy RACH procedure exceeds the maximum number of transmissions, the at least one RACH procedure may be initialized, and retransmission of msg1 may be performed in the remaining RACH procedures. The above-described embodiment may be performed to reduce overhead for the measurement operation of a channel / signal and the RO selection operation based on the measurement result.

[0187] The ramping step for the SBFD RACH procedure and the ramping step for the legacy RACH procedure can be independently set. Considering fairness between SBFD terminals and legacy terminals, the ramping step for the SBFD RACH procedure and the ramping step for the legacy RACH procedure can be set to different values. The terminal can perform transmit power ramping of msg1 in the SBFD RO based on the ramping step for the SBFD RACH procedure. The terminal can perform transmit power ramping of msg1 in the legacy RO based on the ramping step for the legacy RACH procedure. The transmit power ramping of msg1 in the SBFD RACH procedure and the legacy RACH procedure can be performed independently. The transmit power of msg1 can be increased according to the RO type. The base station can set different preamble received target powers for the terminal according to the RO type.

[0188] Proposal #5-2: (Re)transmission procedure of RA preamble based on independent ramping steps and common maximum transmission count

[0189] In the SBFD RACH procedure, the ramping step and the ramping step in the legacy RACH procedure can be independently configured / managed. The maximum number of transmissions can be shared between the SBFD RACH procedure and the legacy RACH procedure. In other words, a common maximum number of transmissions (e.g., the same maximum number of transmissions) can be used between the SBFD RACH procedure and the legacy RACH procedure. The base station can signal the ramping step for the SBFD RACH procedure, the ramping step for the legacy RACH procedure, and the common maximum number of transmissions for the SBFD RACH procedure and the legacy RACH procedure to the terminal. The terminal can receive the ramping step for the SBFD RACH procedure, the ramping step for the legacy RACH procedure, and the common maximum number of transmissions for the SBFD RACH procedure and the legacy RACH procedure from the base station. The terminal can perform the SBFD RACH procedure based on the independent ramping step and the common maximum number of transmissions indicated by the base station. The terminal can perform the legacy RACH procedure based on the independent ramping step and common maximum transmission count indicated by the base station. The (re)transmission procedure of the RA preamble based on Proposal #5-2 can be performed as follows.

[0190] Figure 13 is a conceptual diagram illustrating a (re)transmission procedure of an RA preamble based on proposal #5-2.

[0191] Referring to FIG. 13, the terminal can increase the transmission counter by 1 for each transmission of msg1 regardless of the RO type. The terminal can retransmit msg1 until the number of transmissions of msg1 exceeds the common maximum number of transmissions. The terminal can increase the power ramping counter for each RO type. The terminal can perform transmission power ramping of msg1 in the SBFD RO based on the ramping step for the SBFD RACH procedure. The terminal can perform transmission power ramping of msg1 in the legacy RO based on the ramping step for the legacy RACH procedure. Transmission power ramping of msg1 in the SBFD RACH procedure and the legacy RACH procedure can be performed independently. The transmission power of msg1 can be increased for each RO type.

[0192] Based on Proposal #5-1, flexible control of the RACH procedure may be possible, but the complexity of the system (e.g., the RACH procedure) may increase. Based on Proposal #5-2, the system overhead (e.g., complexity) may be reduced. The transmit power of msg1 may be set to ensure fairness between SBFD terminals and legacy terminals.

[0193] ●Proposal #5-3: (Re)transmission procedure of RA preamble based on common ramping step and independent maximum transmission count

[0194] The maximum number of transmissions in the SBFD RACH procedure and the maximum number of transmissions in the legacy RACH procedure can be independently set / managed. The ramping steps in the SBFD RACH procedure and the legacy RACH procedure can be shared. In other words, a common ramping step (e.g., the same ramping step) can be used in the SBFD RACH procedure and the legacy RACH procedure. The base station can signal the maximum number of transmissions for the SBFD RACH procedure, the maximum number of transmissions for the legacy RACH procedure, and the common ramping step for the SBFD RACH procedure and the legacy RACH procedure to the terminal. The terminal can receive the maximum number of transmissions for the SBFD RACH procedure, the maximum number of transmissions for the legacy RACH procedure, and the common ramping step for the SBFD RACH procedure and the legacy RACH procedure from the base station. The terminal can perform the SBFD RACH procedure based on the common ramping step and the independent maximum number of transmissions indicated by the base station. The terminal can perform the legacy RACH procedure based on the common ramping step and the maximum number of independent transmissions indicated by the base station. The (re)transmission procedure of the RA preamble based on Proposal #5-3 can be performed as follows.

[0195] Figure 14 is a conceptual diagram illustrating a (re)transmission procedure of an RA preamble based on proposal #5-3.

[0196] Referring to FIG. 14, the maximum number of transmissions of msg1 (e.g., RA preamble) can be independently set for each of the SBFD RO (e.g., SBFD RACH procedure) and the legacy RO (e.g., legacy RACH procedure). The maximum number of transmissions of msg1 for the SBFD RO and the maximum number of transmissions of msg1 for the legacy RO can be set differently. The UE can independently check the number of transmissions of msg1 for each RO type. Regardless of the RO type, if the number of transmissions of msg1 exceeds the maximum number of transmissions, the UE can re-perform the channel / signal measurement operation and the RO selection operation based on the measurement result. In other words, if the number of transmissions of msg1 exceeds the maximum number of transmissions in at least one RACH procedure among the SBFD RACH procedure and the legacy RACH procedure, all RACH procedures, i.e., the SBFD RACH procedure and the legacy RACH procedure, can be initialized. Alternatively, if the number of transmissions of msg1 in at least one RACH procedure among the SBFD RACH procedure and the legacy RACH procedure exceeds the maximum number of transmissions, the at least one RACH procedure may be initialized, and retransmission of msg1 may be performed in the remaining RACH procedures.

[0197] The terminal may increase the power ramping counter by 1 for each transmission of msg1 regardless of the RO type. For example, if the transmit power of msg1 in the previous SBFD RO was determined based on the power ramping counter n, the terminal may determine the transmit power of msg1 in the current legacy RO based on the power ramping counter n+1. For another example, if the transmit power of msg1 in the previous legacy RO was determined based on the power ramping counter n, the terminal may determine the transmit power of msg1 in the current SBFD RO based on the power ramping counter n+1. n may be a natural number.

[0198] Proposal #5-3 can be used in environments where channel changes between the terminal and the base station are minimal. Proposal #5-3 can be used to quickly resolve collision issues between SBFD terminals and legacy terminals. When a terminal transmits an RA preamble (e.g., msg1) based on the same channel / signal, the terminal can perform power ramping regardless of the RO type. According to Proposal #5-3, the number of RA preamble transmissions in the UL subband and the number of RA preamble transmissions in the UL region can be independently controlled.

[0199] Proposal #5-4: (Re)transmission procedure of RA preamble based on common ramping step and common maximum transmission count

[0200] The maximum number of transmissions can be shared between the SBFD RACH procedure and the legacy RACH procedure. In other words, a common maximum number of transmissions (e.g., the same maximum number of transmissions) can be used between the SBFD RACH procedure and the legacy RACH procedure. The ramping steps can be shared between the SBFD RACH procedure and the legacy RACH procedure. In other words, a common ramping step (e.g., the same ramping step) can be used between the SBFD RACH procedure and the legacy RACH procedure. The base station can signal the common maximum number of transmissions for the SBFD RACH procedure and the legacy RACH procedure and the common ramping step for the SBFD RACH procedure and the legacy RACH procedure to the terminal. The terminal can receive the common maximum number of transmissions for the SBFD RACH procedure and the legacy RACH procedure and the common ramping step for the SBFD RACH procedure and the legacy RACH procedure from the base station. The terminal can perform a RACH procedure (e.g., SBFD RACH procedure, legacy RACH procedure) based on the common ramping step and common maximum transmission count indicated by the base station. The (re)transmission procedure of the RA preamble based on Proposal #5-4 can be performed as follows.

[0201] Figure 15 is a conceptual diagram illustrating the (re)transmission procedure of an RA preamble based on proposal #5-4.

[0202] Referring to FIG. 15, the terminal may increase the transmission counter by 1 for each transmission of msg1 regardless of the RO type. The terminal may retransmit msg1 until the number of transmissions of msg1 exceeds the common maximum number of transmissions. The terminal may increase the power ramping counter by 1 for each transmission of msg1 regardless of the RO type. For example, if the transmission power of msg1 in the previous SBFD RO was determined based on the power ramping counter n, the terminal may determine the transmission power of msg1 in the current legacy RO based on the power ramping counter n+1. For another example, if the transmission power of msg1 in the previous legacy RO was determined based on the power ramping counter n, the terminal may determine the transmission power of msg1 in the current SBFD RO based on the power ramping counter n+1. n may be a natural number.

[0203] Among Proposals #5-1 through #5-4, Proposal #5-4 may have the lowest signaling overhead and / or system overhead. Proposal #5-4 may be implemented identically or similarly to the legacy RACH procedure. Supporting Proposal #5-4 may require the least changes to the technical specifications.

[0204] RAR Windows

[0205] - Proposal #6

[0206] An SBFD terminal can transmit an RA preamble in both an SBFD RO and a legacy RO. The SBFD terminal can independently perform transmission power control for the RA preamble in each of the SBFD RO and the legacy RO. The RACH procedure for transmitting the RA preamble in each RO type can be performed in parallel. An RAR window can be configured for each RO type. The RAR window for the SBFD RO and the RAR window for the legacy RO can be configured independently. For example, the base station can transmit configuration information for the RAR window for the SBFD RO and the RAR window for the legacy RO to the terminal through signaling. The terminal can receive configuration information for the RAR window for the SBFD RO and the RAR window for the legacy RO from the base station.

[0207] When at least one RAR window among multiple RAR windows expires, the terminal may perform channel / signal measurement operations and RO selection operations based on the measurement results again. The terminal may attempt to transmit msg1 in the selected RO. The terminal may perform operations related to power consumption.

[0208] - Proposal #7

[0209] In the SBFD symbol(s), the RO configuration can be configured based on Scheme #1 or Scheme #2. In Scheme #1, at least one configuration (e.g., most configurations) of the RACH configurations for the N-SBFD terminal can be reused for the RACH configurations for the SBFD terminal. In other words, in Scheme #1, the RACH configuration for the SBFD terminal may not be configured independently from the RACH configuration for the N-SBFD terminal. In Scheme #2, the RACH configuration for the SBFD terminal can be configured independently from the RACH configuration for the N-SBFD terminal. In Scheme #2, the base station can generate the RACH configuration for the N-SBFD terminal and the RACH configuration for the SBFD terminal, respectively, and transmit the RACH configuration for the N-SBFD terminal and the RACH configuration for the SBFD terminal to the terminal. At least one of Scheme #1 and Scheme #2 can be supported.

[0210] In Method #1, the RO can be configured without considering the location of the UL subband. Therefore, it may be necessary to (re)configure the RO considering the location of the UL subband in the frequency domain. This may require reinterpreting the parameters that configure the legacy RO (e.g., msg1-FrequencyStart).

[0211] ●Option #1: Without changing the interpretation of the parameter that configures the legacy RO (e.g., msg1-FrequencyStart), the terminal (e.g., SBFD terminal) can expect to transmit the RA preamble in the legacy RO(s) belonging to the UL-available PRB(s) among the legacy ROs configured by the above parameter.

[0212] ●Option #2: SBFD UEs may reinterpret the parameters that configure legacy ROs (e.g., msg1-FrequencyStart). The starting point of the frequency offset, which indicates the starting point of the legacy RO in the frequency domain, may be the lowest subcarrier (or lowest PRB) of the UL usable PRB(s) rather than the common resource block (CRB). The UE may expect the frequency offset to always be smaller than the size of the UL usable PRB(s). If the frequency offset is set to be larger than the size of the UL usable PRB(s), the UE may not expect transmission of the RA preamble on the UL subband.

[0213] ●Option #3: The base station can signal (e.g., SI signaling, RRC signaling) a fixed frequency offset based on the lowest subcarrier (or lowest PRB) of the UL available PRB(s) to the UE. The frequency offset for the SBFD UE may not be dynamically configured. The UE may receive information about the frequency offset from the base station. The SBFD UE may determine that the RO is configured after the frequency offset or a preset value from the lowest subcarrier (or lowest PRB) of the UL available PRB(s). The preset value may be defined in the technical specification.

[0214] - Proposal #8

[0215] Based on the RO configuration, the RO may exist within the UL subband (e.g., SBFD symbol(s)). Based on the TDD configuration, the SBFD symbol may exist within the DL symbol and / or the FL (flexible) symbol. The RO may span the DL symbol and the FL symbol. The UE may determine the validity of the RO spanning the DL symbol and the FL symbol. If the numerology (e.g., SCS) of the DL symbol is the same as the numerology of the FL symbol, the UE may expect to transmit an RA preamble in the RO spanning the DL symbol and the FL symbol. If the numerology of the DL symbol is different from the numerology of the FL symbol, the UE may determine the RO spanning the DL symbol and the FL symbol as an invalid RO. The UE may not transmit an RA preamble in an invalid RO.

[0216] "If an RO exists within a specific interval from the last DL symbol of an N-SBFD resource (e.g., a DL region)" and / or "if an RO exists within a specific interval from the last DL symbol of an SSB", the UE may not expect to transmit an RA preamble in the RO. In other words, the UE may determine the RO as an invalid RO. Since physical time is required for the UE to switch RF (radio frequency) from DL transmission to UL reception, the RO may be determined as an invalid RO.

[0217] - Proposal #9

[0218] RACH configuration can be performed based on different parameters for SBFD terminals and legacy terminals, respectively. SBFD terminals may not expect to transmit RA preambles in ROs configured for legacy terminals (e.g., legacy ROs). Legacy terminals may not expect to transmit RA preambles in ROs configured for SBFD terminals (e.g., SBFD ROs). Transmitting RA preambles in legacy ROs as well as SBFD ROs by SBFD terminals may cause competition disadvantages to legacy terminals. If certain conditions are met, SBFD terminals may transmit RA preambles in legacy ROs. If fairness issues between SBFD terminals and legacy terminals do not arise, SBFD terminals may expect to transmit RA preambles in legacy ROs. For example, if a legacy RO is set in N-SBFD symbol(s) within a single slot, the SBFD terminal can transmit an RA preamble in the legacy RO.

[0219] - Proposal #10

[0220] A terminal may repeatedly transmit an RA preamble. If the numerology of an SBFD symbol is different from the numerology of an N-SBFD symbol, the terminal may repeatedly transmit the RA preamble in ROs having the same RO type. If certain conditions are satisfied, the terminal may repeatedly transmit the RA preamble in ROs having different RO types (e.g., SBFD RO and legacy RO). The certain conditions may be "if the numerology of an SBFD symbol is the same as the numerology of an N-SBFD symbol", "if there is no time gap between consecutive ROs in the time domain", etc.

[0221] - Proposal #11

[0222] When the RACH configuration is based on method #1, the UE can transmit the RA preamble not only in the legacy RO but also in the SBFD RO (e.g., the additional RO). If the SBFD UE transmits the RA preamble in the legacy RO and the SBFD RO without any restrictions, the probability of the legacy UE transmitting the RA preamble may decrease. The possibility of RA preamble collisions between the SBFD UE and the legacy UE may increase. It may be inappropriate to allow the SBFD UE to transmit the RA preamble in the legacy RO and the SBFD RO. The SBFD UE may be configured to transmit the RA preamble in some ROs when certain conditions are met.

[0223] ●Option #1: The base station can instruct the SBFD terminal to transmit the RA preamble in a specific RO through signaling (e.g., RRC signaling, MAC CE signaling, and / or DCI signaling). The SBFD terminal can receive the instruction from the base station and transmit the RA preamble in the specific RO based on the instruction.

[0224] ●Option #2: Within a single RO period, the UE may expect transmission of an RA preamble (e.g., msg1) from either a legacy RO or an SBFD RO (e.g., an additional RO). An RO may be determined based on priorities. For example, an RO with a higher priority or an RO with a lower priority may be selected for transmission of the RA preamble. The priorities of the legacy RO and / or the SBFD RO may be defined in the technical specifications. If the priority of the additional RO is higher than that of the legacy RO, and both the additional RO and the legacy RO exist within a single RO period, the UE may expect transmission of the RA preamble from the additional RO. If the UE selects a specific RO type, the UE may transmit the RA preamble only on the selected RO type. The base station may set restrictions (e.g., a maximum number of RA preamble transmissions) for the UE to prevent repeated transmission of the RA preamble on the same RO type.

[0225] The base station can set the maximum number of transmissions of the RA preamble for each RO type and transmit information about the maximum number of transmissions to the terminal through signaling. In other words, the base station can transmit information about the maximum number of transmissions of the RA preamble in an SBFD RO (e.g., an additional RO) and / or information about the maximum number of transmissions of the RA preamble in a legacy RO to the terminal. The maximum number of transmissions of the RA preamble in an SBFD RO and the maximum number of transmissions of the RA preamble in a legacy RO can be independently set. For example, the maximum number of transmissions of the RA preamble in an SBFD RO can be different from the maximum number of transmissions of the RA preamble in a legacy RO. Alternatively, a common maximum number of transmissions can be set regardless of the RO type. The base station can transmit information about the common maximum number of transmissions of the RA preamble to the terminal through signaling. The terminal can receive information about the common maximum number of transmissions of the RA preamble from the base station. Information on the maximum number of transmissions of the RA preamble can indicate two transmissions, four transmissions, or eight transmissions of the RA preamble.

[0226] The terminal can select one of the SBFD RO and the legacy RO, and can transmit the RA preamble in the selected RO. If the RA procedure is not completed and the number of transmissions of the RA preamble in one RO exceeds the maximum number of transmissions, the terminal can attempt to transmit the RA preamble in another RO instead of one RO. If one RO is an SBFD RO, the other RO can be a legacy RO. If one RO is a legacy RO, the other RO can be an SBFD RO. For example, the terminal can transmit msg1 in the SBFD RO. If the RA procedure is not completed and the number of transmissions of msg1 in the SBFD RO exceeds the maximum number of transmissions, the terminal can transmit msg1 in the legacy RO instead of the SBFD RO. In other words, the terminal can change the RO type for transmitting msg1. If msg1 transmission was performed in SBFD RO, the terminal can set the RO type to legacy RO and retransmit msg1 in legacy RO.

[0227] When the RO type for transmitting msg1 is changed from SBFD RO to legacy RO, the transmission power of the first msg1 in the legacy RO may be determined based on the initial value of the preamble power ramping counter. Alternatively, when the RO type for transmitting msg1 is changed from SBFD RO to legacy RO, the transmission power of the first msg1 in the legacy RO may be determined based on a preamble power ramping counter that is increased by 1 from the preamble power ramping counter used to determine the transmission power of the last msg1 in the SBFD RO. The preamble power ramping step used to determine the transmission power of msg1 in the legacy RO may be the same as or may be set in the terminal independently of the preamble power ramping step used to determine the transmission power of msg1 in the SBFD RO. If the RA procedure is not completed and the number of transmissions of msg1 in the changed RO type, which is a legacy RO, exceeds the maximum number of transmissions, the terminal may not change the RO type for msg1 transmission and may terminate the RA procedure. In this case, the terminal may reselect another cell (e.g., a base station) to perform the RA procedure and perform the RA procedure for the other cell. In the RA procedure, the change of the RO type for msg1 transmission may be performed only once, and the change of the RO type for msg1 transmission may not be permitted to be performed more than once.

[0228] For another example, the terminal may transmit msg1 in a legacy RO. If the RA procedure is not completed and the number of transmissions of msg1 in the legacy RO exceeds the maximum number of transmissions, the terminal may transmit msg1 in a SBFD RO instead of the legacy RO. In other words, the terminal may change the RO type for transmitting msg1. If the msg1 transmission was performed in the legacy RO, the terminal may set the RO type to SBF RO and transmit msg1 again in the SBFD RO. If the RO type for transmitting msg1 is changed from the legacy RO to the SBFD RO, the transmit power of the first msg1 in the SBFD RO may be determined based on the initial value of the preamble power ramping counter. Alternatively, if the RO type for transmitting msg1 is changed from a legacy RO to an SBFD RO, the transmit power of the first msg1 in the SBFD RO may be determined based on a preamble power ramping counter that is increased by 1 from the preamble power ramping counter used to determine the transmit power of the last msg1 in the legacy RO. The preamble power ramping step used to determine the transmit power of msg1 in the legacy RO may be the same as or independently set in the terminal from the preamble power ramping step used to determine the transmit power of msg1 in the SBFD RO. If the RA procedure is not completed and the number of transmissions of msg1 in the changed RO type, SBFD RO, exceeds the maximum number of transmissions, the terminal may not change the RO type for transmitting msg1 and may terminate the RA procedure. In this case, the terminal may reselect another cell (e.g., a base station) to perform the RA procedure and perform the RA procedure for the other cell. In the RA procedure, the change of RO type for transmitting msg1 can be performed only once, and the change of RO type for transmitting msg1 can not be performed more than twice.

[0229] Alternatively, the terminal can select an RO type (e.g., SBFD RO or Legacy RO) for each retransmission of msg1, and transmit msg1 in the selected RO type. For example, the terminal can transmit msg1 in SBFD RO (or Legacy RO), and if msg1 transmission in SBFD RO (or Legacy RO) fails, the terminal can change the RO type to Legacy RO (or SBFD RO), and retransmit msg1 in Legacy RO (or SBFD RO).

[0230] - Proposal #12

[0231] Resources used for the RACH procedure of an SBFD terminal in an RRC inactive state and / or an RRC idle state can be defined. For example, a UL available PRB and / or a DL available PRB for the RACH procedure of an SBFD terminal in an RRC inactive state and / or an RRC idle state can be configured. A base station can transmit configuration information of the UL available PRB and / or the DL available PRB for the RACH procedure of an SBFD terminal in an RRC inactive state and / or an RRC idle state to the SBFD terminal through signaling. The SBFD terminal can receive configuration information of the UL available PRB and / or the DL available PRB for the RACH procedure of an SBFD terminal in an RRC inactive state and / or an RRC idle state from the base station. The UL available PRB may refer to a UL subband existing in an initial UL BWP. DL available PRB may refer to a DL subband existing within the initial DL BWP.

[0232] In the present disclosure, a UL subband may refer to a UL subband for SBFD operation. In the present disclosure, a terminal may transmit information indicating whether it supports the function(s) proposed in the present disclosure to a base station. Information indicating whether it supports the function(s) may be included in a UE capability report. The base station may receive a UE capability report from the terminal and perform signaling and / or operations based on information included in the UE capability information (e.g., information indicating whether it supports the function(s)).

[0233] The configuration for the UL subband (e.g., SBFD configuration) can be transmitted via signaling (e.g., RRC signaling). The SBFD configuration can be transmitted after the transmission of the TDD common configuration. The methods proposed in this disclosure can be applied to licensed bands as well as unlicensed bands. The methods proposed in this disclosure can be applied to sidelink and / or supplementary uplink (SUL). For example, the methods proposed in this disclosure can be applied to determine the transmit power in sidelink and / or SUL. Each of the proposals of this disclosure can be applied independently, or a combination of the proposals of this disclosure can be applied. Some of the proposals of this disclosure can be applied to other proposals. Each of the options of this disclosure can be applied independently, or a combination of the options of this disclosure can be applied. Some of the options of this disclosure can be applied to other options. The proposals and / or options of this disclosure can be applied regardless of the RRC state of the UE. For example, a terminal in an RRC idle state, a terminal in an RRC inactive state, and / or a terminal in an RRC connected state can perform the proposals and / or options of the present disclosure. A base station can perform the proposals and / or options of the present disclosure for a terminal in an RRC idle state, a terminal in an RRC inactive state, and / or a terminal in an RRC connected state.

[0234] The operations of the method according to the present disclosure can be implemented as a computer-readable program or code on a computer-readable recording medium. A computer-readable recording medium includes any type of recording device that stores information readable by a computer system. Furthermore, a computer-readable recording medium can be distributed across network-connected computer systems, allowing the computer-readable program or code to be stored and executed in a distributed manner.

[0235] Additionally, the computer-readable recording medium may include hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, flash memory, etc. The program instructions may include not only machine language codes produced by a compiler, but also high-level language codes that can be executed by a computer using an interpreter, etc.

[0236] While some aspects of the present disclosure have been described in the context of a device, they may also represent a description of a corresponding method, wherein a block or device corresponds to a method step or a feature of a method step. Similarly, aspects described in the context of a method may also be described as a corresponding block or item or a feature of a corresponding device. Some or all of the method steps may be performed by (or using) a hardware device, such as, for example, a microprocessor, a programmable computer, or an electronic circuit. In some embodiments, at least one or more of the most significant method steps may be performed by such a device.

[0237] A programmable logic device (e.g., a field-programmable gate array) may be used to perform some or all of the functions of the methods described in the present disclosure. The field-programmable gate array may operate in conjunction with a microprocessor to perform one of the methods described in the present disclosure. In general, the methods are preferably performed by some hardware device.

[0238] Although the present disclosure has been described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various modifications and changes may be made to the present disclosure without departing from the spirit and scope of the present disclosure as set forth in the claims below.

Claims

1. As a method of UE (user equipment), A step of measuring a signal received from a base station; A step of selecting one RO type among N-SBFD (non-subband full duplex) RO (RACH (random access channel) occasion) and SBFD RO based on whether the measured RSRP (reference signal received power) of the signal satisfies the RSRP threshold; and A step of transmitting a random access (RA) preamble to the base station from at least one RO among a plurality of ROs corresponding to the one RO type, UE's method.

2. In claim 1, A step of selecting another RO type among the N-SBFD RO and the SBFD RO based on the measured RSRP not satisfying the RSRP threshold; and Further comprising the step of transmitting the RA preamble to the base station from at least one RO among a plurality of ROs corresponding to the other RO type. UE's method.

3. In claim 2, wherein each of said one RO type and said other RO type is said SBFD RO and said N-SBFD RO, or each of said one RO type and said other RO type is said N-SBFD RO and said SBFD RO, UE's method.

4. In claim 1, Further comprising a step of receiving information on the RSRP threshold from the base station, The above RSRP threshold is set for selecting the RO type for transmission of the RA preamble. UE's method.

5. In claim 1, Based on the RO type to which the RA preamble is transmitted being not indicated by the base station, the UE selects one RO among the N-SBFD RO and the SBFD RO based on the comparison result between the measured RSRP and the RSRP threshold. UE's method.

6. In claim 1, The operation of selecting the one RO based on the comparison result between the measured RSRP and the RSRP threshold by the UE is performed in an RA procedure excluding the RA procedure initiated by a PDCCH (physical downlink control channel) order transmitted by the base station. UE's method.

7. In claim 1, The step of transmitting the above RA preamble to the base station is: A step of repeatedly transmitting the RA preamble to the base station in ROs a number of repetitions associated with the RSRP repetition threshold based on the measured RSRP satisfying the RSRP repetition threshold, The above RSRP repetition threshold is independently set for each of the N-SBFD RO and the SBFD RO. UE's method.

8. In claim 1, The above N-SBFD RO is set in the N-SBFD resource, the above SBFD RO is set in the SBFD resource, and the UE supports the SBFD operation. UE's method.

9. As a method of base station, A step of transmitting configuration information of N-SBFD (non-subband full duplex) RO (RACH (random access channel) occasion) and configuration information of SBFD RO to UE (user equipment); A step of transmitting information on a RSRP (reference signal received power) threshold used to select an RO type for transmission of an RA (random access) preamble to the UE; a step of transmitting a signal to the UE; and A step of receiving the RA preamble from the UE in at least one of a plurality of ROs corresponding to a selected RO type based on a comparison result between the measured RSRP of the signal and the RSRP threshold, The RO corresponding to the above RO type is the N-SBFD RO or the SBFD RO. Base station method.

10. In claim 9, One RO type is selected from among the N-SBFD RO and the SBFD RO based on whether the measured RSRP satisfies the RSRP threshold, and another RO type is selected from among the N-SBFD RO and the SBFD RO based on whether the measured RSRP does not satisfy the RSRP threshold. Base station method.

11. In claim 10, wherein each of said one RO type and said other RO type is said SBFD RO and said N-SBFD RO, or each of said one RO type and said other RO type is said N-SBFD RO and said SBFD RO, Base station method.

12. In claim 9, Based on the RO type through which the RA preamble is transmitted being not indicated by the base station, the RO type for transmission of the RA preamble is selected based on the comparison result between the measured RSRP and the RSRP threshold. Base station method.

13. In claim 9, In an RA procedure other than an RA procedure initiated by a PDCCH (physical downlink control channel) order transmitted by the base station, the RO type for transmission of the RA preamble is selected based on a comparison result between the measured RSRP and the RSRP threshold. Base station method.

14. In claim 9, The above N-SBFD RO is set in N-SBFD (non-subband full duplex) resources, the above SBFD RO is set in SBFD resources, and the UE supports SBFD operation. Base station method.

15. As UE (user equipment), Contains at least one processor, At least one processor of the UE, Measure the signal received from the base station; Selecting one RO type among N-SBFD (non-subband full duplex) RO (RACH (random access channel) occasion) and SBFD RO based on whether the measured RSRP (reference signal received power) of the above signal satisfies the RSRP threshold; and Causing at least one RO among a plurality of ROs corresponding to the above one RO type to transmit a random access (RA) preamble to the base station, UE.

16. In claim 15, At least one processor of the UE, Selecting another RO type among the N-SBFD RO and the SBFD RO based on the measured RSRP not satisfying the RSRP threshold; and Further causing at least one RO among a plurality of ROs corresponding to the other RO type to transmit the RA preamble to the base station, UE.

17. In claim 15, At least one processor of the UE, Further causing the information of the RSRP threshold to be received from the base station, The above RSRP threshold is set for selecting the RO type for transmission of the RA preamble. UE.

18. In claim 15, Based on the RO type to which the RA preamble is transmitted being not indicated by the base station, the UE selects one RO among the N-SBFD RO and the SBFD RO based on the comparison result between the measured RSRP and the RSRP threshold. UE.

19. In claim 15, The operation of selecting the one RO based on the comparison result between the measured RSRP and the RSRP threshold by the UE is performed in an RA procedure excluding the RA procedure initiated by a PDCCH (physical downlink control channel) order transmitted by the base station. UE.

20. In claim 15, To transmit the RA preamble to the base station, the at least one processor causes the UE to: Based on the measured RSRP satisfying the RSRP repetition threshold, causing the RA preamble to be repeatedly transmitted to the base station in the number of ROs corresponding to the number of repetitions associated with the RSRP repetition threshold, The above RSRP repetition threshold is independently set for each of the N-SBFD RO and the SBFD RO. UE.

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