Method and apparatus for transmitting and receiving uplink channel in non-terrestrial network

Abstract

A method and apparatus for transmitting and receiving an uplink channel in a non-terrestrial network are disclosed. A method of a first communication node comprises the steps of: mapping a modulation symbol and a reference signal to a resource region; obtaining information on the phase shift of each subcarrier in the resource region; applying a phase shift to each subcarrier to perform a first pre-compensation operation on the phase; and transmitting the signal to which the first pre-compensation operation is applied to the second communication node.

Description

Technical Field

[0001] The present invention relates to an uplink transmission technology in a non-terrestrial network, and more particularly, to a repeated transmission technology for a physical uplink shared channel (PUSCH). Background Art

[0002] Communication networks (e.g., 5G communication networks, 6G communication networks, etc.) are being developed to provide enhanced communication services compared to existing communication networks (e.g., long term evolution (LTE), LTE-Advanced (LTE-A), etc.). 5G communication networks (e.g., New Radio (NR) communication networks) can support not only frequency bands of 6 GHz or below, but also frequency bands of 6 GHz or above. That is, the 5G communication network can support the frequency range FR1 band and / or FR2 band. Compared with the LTE communication network, the 5G communication network can support a wide variety of communication services and scenarios. For example, the usage scenarios of the 5G communication network may include enhanced Mobile BroadBand (eMBB), Ultra Reliable Low Latency Communication (URLLC), massive Machine Type Communication (mMTC), etc.

[0003] Compared with 5G communication networks, 6G communication networks can support a wide variety of communication services and scenarios. 6G communication networks can meet the requirements of ultra-performance, ultra-bandwidth, ultra-space, ultra-precision, ultra-intelligence and / or ultra-reliability. 6G communication networks can support various broadbands and can be applied to various usage scenarios (e.g., terrestrial communication, non-terrestrial communication, sidelink communication, etc.).

[0004] A communication network (e.g., a 5G communication network, a 6G communication network, etc.) can provide communication services to terminals located on the ground. Recently, the demand for communication services not only for the ground but also for non-ground aircraft, drones, and satellites has been increasing, and for this purpose, the technology of non-terrestrial networks (NTN) has been discussed. The non-terrestrial network can be implemented based on 5G communication technology, 6G communication technology, etc. For example, in a non-terrestrial network, communication between a satellite and a ground communication node or a non-terrestrial communication node (e.g., an aircraft, a drone, etc.) can be performed based on 5G communication technology, 6G communication technology, etc. In NTN, a satellite can perform the function of a base station in a communication network (e.g., a 5G communication network, a 6G communication network, etc.).

[0005] On the other hand, in non-terrestrial networks, the time offset (e.g., the time offset between the downlink time and the uplink time) may change rapidly due to the movement of the satellite, and the time offset can be controlled by timing advance control (TAC). In other words, the base station can control the time offset based on the TAC so that the uplink signal / channel of the terminal arrives at the base station according to the target timing advance (TA). However, when the transmission timing of the terminal is changed by TAC, power consistency and / or phase continuity may not be maintained. In other words, the time domain window (TDW) may be terminated. In this case, the gain of the joint channel estimation may be reduced. Therefore, a method for solving this problem is needed. Summary of the invention

[0006] Technical issues

[0007] The present invention is directed to providing a method and apparatus for repeated transmission of a PUSCH in a non-terrestrial network.

[0008] Technical Solution

[0009] A method of a first communication node according to an exemplary embodiment of the present invention for achieving the above-mentioned purpose may include: mapping modulation symbols and reference signals to a resource region; obtaining information about a phase shift of each subcarrier within the resource region; performing a first precompensation operation of a phase by applying a phase shift to each subcarrier; and sending a signal to which the first precompensation operation is applied to a second communication node.

[0010] Obtaining information about the phase shift may include predicting the phase shift based on a position of a reference subcarrier, a phase shift difference between the reference subcarrier and another subcarrier, and a timing offset.

[0011] The timing offset may be a difference between a synchronization reference time and a predicted reception time of a received signal at the second communication node, and the timing offset may be determined based on a distance between the first communication node and the second communication node.

[0012] Obtaining information about the phase shift may include receiving, from the second communication node, information about the phase shift predicted based on a position of a reference subcarrier, a phase shift difference between the reference subcarrier and another subcarrier, and a timing offset.

[0013] The method may further include: performing an inverse fast Fourier transform (IFFT) operation on a result of the first precompensation operation; obtaining information of a cyclic shift for a second precompensation operation of time; and performing a second precompensation operation of time by applying the cyclic shift to the result of the IFFT operation; wherein the signal sent to the second communication node may be a signal to which the first precompensation operation and the second precompensation operation are applied.

[0014] Obtaining information of the cyclic shift may include determining the cyclic shift based on a timing offset caused by movement of the second communication node and an IFFT size of an IFFT operation.

[0015] Acquiring the information of the cyclic shift may include receiving, from the second communication node, information about the cyclic shift determined based on a timing offset caused by movement of the second communication node and an IFFT size of an IFFT operation.

[0016] The method may further include: sending information indicating that the first communication node supports the first pre-compensation operation to the second communication node; and receiving information indicating that the post-compensation operation of the second communication node is disabled from the second communication node.

[0017] The transmission of the signal may be a repeated physical uplink shared channel (PUSCH) transmission, and power consistency and phase continuity may be maintained by performing a first pre-compensation operation within a time domain window (TDW) in which the repeated PUSCH transmission is performed.

[0018] The first communication node may be a terminal in a non-terrestrial network, and the second communication node may be a satellite or a base station in the non-terrestrial network.

[0019] A first communication node according to an exemplary embodiment of the present invention for achieving the above-mentioned purpose may include at least one processor, wherein the at least one processor enables the first communication node to execute: mapping modulation symbols and reference signals to a resource region; obtaining information about a phase shift of each subcarrier within the resource region; performing a first precompensation operation of a phase by applying a phase shift to each subcarrier; and sending a signal to which the first precompensation operation is applied to a second communication node.

[0020] Upon obtaining the information about the phase shift, the at least one processor may further cause the first communication node to perform: predicting the phase shift based on a position of a reference subcarrier, a phase shift difference between the reference subcarrier and another subcarrier, and a timing offset.

[0021] The timing offset may be a difference between a synchronization reference time and a predicted reception time of a received signal at the second communication node, and the timing offset may be determined based on a distance between the first communication node and the second communication node.

[0022] When obtaining information about the phase shift, the at least one processor may further cause the first communication node to perform: receiving from the second communication node information about the phase shift predicted based on the position of the reference subcarrier, the phase shift difference between the reference subcarrier and another subcarrier, and the timing offset.

[0023] The at least one processor may further cause the first communication node to: perform an inverse fast Fourier transform (IFFT) operation on a result of the first precompensation operation; obtain information of a cyclic shift for a second precompensation operation of time; and perform a second precompensation operation of time by applying the cyclic shift to the result of the IFFT operation; wherein the signal sent to the second communication node may be a signal to which the first precompensation operation and the second precompensation operation are applied.

[0024] When obtaining the information of the cyclic shift, the at least one processor may further cause the first communication node to perform: determining the cyclic shift based on a timing offset caused by movement of the second communication node and an IFFT size of an IFFT operation.

[0025] When obtaining the information of the cyclic shift, the at least one processor may further cause the first communication node to perform: receiving, from the second communication node, information about the cyclic shift determined based on a timing offset caused by movement of the second communication node and an IFFT size of an IFFT operation.

[0026] The at least one processor may further cause the first communication node to execute: sending information to the second communication node indicating that the first communication node supports the first pre-compensation operation; and receiving information from the second communication node indicating that the post-compensation operation of the second communication node is disabled.

[0027] The transmission of the signal may be a repeated physical uplink shared channel (PUSCH) transmission, and power consistency and phase continuity may be maintained by performing a first pre-compensation operation within a time domain window (TDW) in which the repeated PUSCH transmission is performed.

[0028] The first communication node may be a terminal in a non-terrestrial network, and the second communication node may be a satellite or a base station in the non-terrestrial network.

[0029] Beneficial effects

[0030] According to the present invention, a transmitting node can compensate for phase and / or time by performing a pre-compensation operation on phase and / or time, and can transmit a signal / channel to which the pre-compensation operation is applied. A receiving node can compensate for phase and / or time by performing a post-compensation operation on a signal received from a transmitting node. According to the pre-compensation operation and / or the post-compensation operation, power consistency and / or phase continuity can be maintained within a time domain window (TDW), thereby increasing the gain of a joint channel estimation and thus improving the receiving performance of a signal / channel. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1a is a conceptual diagram illustrating a first exemplary embodiment of a non-terrestrial network.

[0032] Figure 1b is a conceptual diagram illustrating a second exemplary embodiment of a non-terrestrial network.

[0033] Figure 2a is a conceptual diagram illustrating a third exemplary embodiment of a non-terrestrial network.

[0034] Figure 2b is a conceptual diagram illustrating a fourth exemplary embodiment of a non-terrestrial network.

[0035] Figure 2c is a conceptual diagram illustrating a fifth exemplary embodiment of a non-terrestrial network.

[0036] Figure 3 is a block diagram illustrating a first exemplary embodiment of communication nodes constituting a non-terrestrial network.

[0037] Figure 4 is a block diagram illustrating a first exemplary embodiment of a communication node performing communications.

[0038] Figure 5a is a block diagram illustrating a first exemplary implementation of a transmit path.

[0039] Figure 5b is a block diagram illustrating a first exemplary implementation of a receive path.

[0040] Figure 6a is a conceptual diagram illustrating a first exemplary embodiment of a protocol stack of a user plane in a non-terrestrial network based on a transparent payload.

[0041] Figure 6b is a conceptual diagram illustrating a first exemplary embodiment of a protocol stack of a control plane in a non-terrestrial network based on a transparent payload.

[0042] Figure 7a is a conceptual diagram illustrating a first exemplary embodiment of a protocol stack for a user plane in a non-terrestrial network based on a regenerative payload.

[0043] Figure 7b is a conceptual diagram illustrating a first exemplary embodiment of a protocol stack for a control plane in a non-terrestrial network based on a regenerative payload.

[0044] Figure 8 is a conceptual diagram of a first exemplary embodiment illustrating a change in a distance between a satellite and a terminal according to movement (eg, position) of the satellite and / or the terminal during TDW in a non-terrestrial network based on a regenerative payload.

[0045] Fig. 9 is a conceptual diagram of a first exemplary embodiment illustrating a change in a distance between a satellite and a terminal according to movement (eg, position) of the satellite and / or the terminal during TDW in a transparent payload-based non-terrestrial network.

[0046] Fig.10 is a conceptual diagram illustrating a first exemplary embodiment of timing drift of PUSCH transmission in a non-terrestrial network.

[0047] Fig.11 is a block diagram illustrating a first exemplary embodiment of a transmitting node performing a pre-compensation operation.

[0048] Fig.12 is a block diagram illustrating a second exemplary embodiment of a transmitting node performing a pre-compensation operation.

[0049] Fig.13 is a block diagram illustrating a first exemplary implementation of a receiving node that performs a post-compensation operation.

[0050] Fig.14 is a block diagram illustrating a second exemplary embodiment of a receiving node that performs a post-compensation operation.

[0051] Fig.15a is a conceptual diagram illustrating a first exemplary embodiment of a general CP deletion operation.

[0052] Fig.15b is a conceptual diagram illustrating a first exemplary embodiment of an adaptive CP deletion operation. DETAILED DESCRIPTION

[0053] Although the present invention is capable of various modifications and alternative forms, specific embodiments thereof are shown by way of example in the accompanying drawings and will be described in detail herein. However, it should be understood that it is not intended to limit the present invention to the specific forms disclosed, but on the contrary, the present invention covers all modifications, equivalents and alternative forms that fall within the spirit and scope of the present invention. Throughout the description of the drawings, the same reference numerals refer to the same elements.

[0054] It will be understood that, although the terms first, second, etc. can be used herein to describe each element, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, without departing from the scope of the present invention, the first element can be referred to as the second element and similarly, the second element can be referred to as the first element. As used in this article, the term "and / or" includes any combination and all combinations of one or more related enumeration items.

[0055] In the present invention, “at least one of A and B” may mean “at least one of A or B” or “at least one of a combination of one or more of A and B”. Furthermore, in an exemplary embodiment of the present invention, “one or more of A and B” may mean “one or more of A or B” or “one or more of a combination of one or more of A and B”.

[0056] In the present invention, "(re)transmission" may mean "transmission", "retransmission" or "transmission and retransmission", "(re)configuration" may mean "configuration", "reconfiguration" or "configuration and reconfiguration", "(re)connection" may mean "connection", "reconnection" or "connection and reconnection", and "(re)access" may mean "access", "reaccess" or "access and reaccess".

[0057] It will be understood that when an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element, or there can be intervening elements. Conversely, when an element is referred to as being "directly connected" or "directly coupled" to another element, there are no intervening elements.

[0058] The terms used in this article are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in this article, the singular form is intended to also include the plural form, unless the context clearly indicates otherwise. It will be further understood that when the terms "include" and / or "comprising" are used in this article, it is explained that there are described features, numerical values, steps, operations, elements, components or combinations thereof, but does not exclude the presence or addition of one or more other features, numerical values, steps, operations, elements, components and / or combinations thereof.

[0059] Unless otherwise defined, all terms (including technical and scientific terms) used in this article have the same meaning as those commonly understood by ordinary technicians in the field to which the present invention belongs. It will be further understood that terms (for example, 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 will not be interpreted as an idealized or overly formal meaning unless explicitly defined as such in this article.

[0060] Hereinafter, the exemplary embodiments of the present invention will be described in more detail with reference to the accompanying drawings. In order to promote overall understanding when describing the present invention, the same components in the accompanying drawings are represented by the same reference numerals, and repeated descriptions thereof will be omitted. In addition to the exemplary embodiments clearly described in the present invention, operations can also be performed according to the combination of the exemplary embodiments, the expansion of the exemplary embodiments and / or the modification of the exemplary embodiments. The execution of some operations can be omitted, and the execution order of the operations can be changed.

[0061] Even when describing a method performed at a first communication node among communication nodes (e.g., transmission or reception of a signal), the corresponding second communication node may perform a method corresponding to the method performed at the first communication node (e.g., reception or transmission of a signal). That is, when describing the operation of a user equipment (UE), a base station corresponding to the UE may perform an operation corresponding to the operation of the UE. Conversely, when describing the operation of a base station, a UE corresponding to the base station may perform an operation corresponding to the operation of the base station. In a non-terrestrial network (NTN) (e.g., a payload-based NTN), the operation of a base station may refer to the operation of a satellite, and the operation of a satellite may refer to the operation of a base station.

[0062] A base station may refer to a node B, an evolved node B (eNodeB), a next generation node B (gNodeB), a gNB, a device, an apparatus, a node, a communication node, a base transceiver station (BTS), a radio remote head (RRH), a transmission reception point (TRP), a radio unit (RU), a roadside unit (RSU), a radio transceiver, an access point, an access node, etc. A UE may refer to 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 on-board unit (OBU), etc.

[0063] In the present invention, signaling may be at least one of higher layer signaling, medium access control (MAC) signaling, or physical (PHY) signaling. A message for higher layer signaling may be referred to as a "higher layer message" or a "higher layer signaling message". A message for MAC signaling may be referred to as a "MAC message" or a "MAC signaling message". A message for PHY signaling may be referred to as a "PHY message" or a "PHY signaling message". Higher layer signaling may refer to the sending and receiving operations of system information (e.g., master information block (MIB), system information block (SIB)) and / or RRC messages. MAC signaling may refer to the sending and receiving operations of a MAC control element (CE). PHY signaling may refer to the sending and receiving operations of control information (e.g., downlink control information (DCI), uplink control information (UCI), and sidelink control information (SCI)).

[0064] In the present invention, “configure an operation (e.g., send an operation)” may mean “send configuration information (e.g., information element or parameter) of an operation and / or information indicating the execution of an operation with a signal”. “Configure an information element (e.g., parameter)” may mean “send a corresponding information element with a signal”. In the present invention, “signal and / or channel” may mean signal, channel, or “signal and channel”, and “signal” may be used to mean “signal and / or channel”.

[0065] The communication system may include at least one of a terrestrial network, a non-terrestrial network, a 4G communication network (e.g., a long term evolution (LTE) communication network), a 5G communication network (e.g., a new radio (NR) communication network), or a 6G communication network. Each of the 4G communication network, the 5G communication network, and the 6G communication network may include a terrestrial network and / or a non-terrestrial network. The non-terrestrial network may operate based on at least one communication technology of the LTE communication technology, the 5G communication technology, or the 6G communication technology. The non-terrestrial network may provide communication services in various frequency bands.

[0066] The communication network to which the exemplary embodiment is applied is not limited to the content described below, and the exemplary embodiment can be applied to various communication networks (e.g., 4G communication network, 5G communication network and / or 6G communication network). Here, the communication network can be used in the same sense as the communication system.

[0067] Figure 1a is a conceptual diagram illustrating a first exemplary embodiment of a non-terrestrial network.

[0068] like Figure 1a As shown, the non-terrestrial network (NTN) may include a satellite 110, a communication node 120, a gateway 130, a data network 140, etc. A unit including the satellite 110 and the gateway 130 may correspond to a remote radio unit (RRU). Figure 1a The NTN shown may be a transparent payload-based NTN. Satellite 110 may be a low earth orbit (LEO) satellite, a medium earth orbit (MEO) satellite, a geostationary earth orbit (GEO) satellite, a high elliptical orbit (HEO) satellite, or an unmanned aircraft system (UAS) platform. The UAS platform may include a high altitude platform station (HAPS). The non-GEO satellite may be a LEO satellite and / or a MEO satellite.

[0069] The communication node 120 may include a communication node located at a ground location (e.g., a user equipment (UE) or a terminal) and a communication node located in a non-ground space (e.g., an aircraft, a drone). A service link may be established between the satellite 110 and the communication node 120, and the service link may be a radio link. The satellite 110 may provide communication services to the communication node 120 using one or more beams. The shape of the coverage area of ​​the beam of the satellite 110 may be elliptical or circular.

[0070] In non-terrestrial networks, the following three types of service links can be supported.

[0071] - Earth-fixed: The service link may be provided by a beam that always continuously covers the same geographical area (eg, a geosynchronous orbit (GSO) satellite).

[0072] - quasi-earth-fixed: the service link may be provided by a beam covering one geographical area during a defined period and by a beam covering another geographical area during another period (e.g. a non-GSO (NGSO) satellite forming a steerable beam).

[0073] - Earth-moving: The service link may be provided by a beam moving over the surface of the Earth (eg, a NGSO satellite forming a fixed or non-steerable beam).

[0074] The communication node 120 may perform communication (e.g., downlink communication and uplink communication) with the satellite 110 using 4G communication technology, 5G communication technology, and / or 6G communication technology. Communication between the satellite 110 and the communication node 120 may be performed using an NR-Uu interface and / or a 6G-Uu interface. When supporting dual connectivity (DC), the communication node 120 may be connected to other base stations (e.g., base stations supporting 4G, 5G, and / or 6G functions) and the satellite 110, and perform DC operations based on technologies defined in 4G, 5G, and / or 6G technical specifications.

[0075] The gateway 130 may be located at a ground location, and a feeder link may be established between the satellite 110 and the gateway 130. The feeder link may be a radio link. The gateway 130 may be referred to as a "non-terrestrial network (NTN) gateway". The communication between the satellite 110 and the gateway 130 may be performed based on an NR-Uu interface, a 6G-Uu interface, or a satellite radio interface (SRI). The gateway 130 may be connected to the data network 140. There may be a "core network" between the gateway 130 and the data network 140. In this case, the gateway 130 may be connected to the core network, and the core network may be connected to the data network 140. The core network may support 4G communication technology, 5G communication technology, and / or 6G communication technology. For example, the core network may include an access and mobility management function (AMF), a user plane function (UPF), a session management function (SMF), and the like. Communication between the gateway 130 and the core network may be performed based on an NG-C / U interface or a 6G-C / U interface.

[0076] like Figure 1b As shown in the exemplary embodiment of FIG. 1 , in a transparent payload-based NTN, a “core network” may exist between the gateway 130 and the data network 140 .

[0077] Figure 1b is a conceptual diagram illustrating a second exemplary embodiment of a non-terrestrial network.

[0078] like Figure 1b As shown, the gateway can be connected to the base station, the base station can be connected to the core network, and the core network can be connected to the data network. Each of the base station and the core network can support 4G communication technology, 5G communication technology and / or 6G communication technology. The communication between the gateway and the base station can be performed based on the NR-Uu interface or the 6G-Uu interface, and the communication between the base station and the core network (e.g., AMF, UPF, SMF, etc.) can be performed based on the NG-C / U interface or the 6G-C / U interface.

[0079] Figure 2a is a conceptual diagram illustrating a third exemplary embodiment of a non-terrestrial network.

[0080] like Figure 2a As shown, the non-terrestrial network may include a first satellite 211, a second satellite 212, a communication node 220, a gateway 230, a data network 240, and the like. Figure 2a The NTN shown may be an NTN based on a regenerated payload. For example, each of satellite 211 and satellite 212 may perform a regeneration operation (e.g., demodulation, decoding, re-encoding, re-modulation, and / or filtering operation) on a payload received from another entity (e.g., communication node 220 or gateway 230) and transmit the regenerated payload.

[0081] Each of satellite 211 and satellite 212 can be a LEO satellite, a MEO satellite, a GEO satellite, a HEO satellite or a UAS platform. The UAS platform can include a HAPS. Satellite 211 can be connected to satellite 212, and an inter-satellite link (ISL) can be established between satellite 211 and satellite 212. ISL can operate in an RF band or an optical band. ISL can be optionally established. Communication node 220 can include a ground communication node (e.g., UE or terminal) and a non-ground communication node (e.g., an aircraft or a drone). A service link (e.g., a radio link) can be established between satellite 211 and communication node 220. Satellite 211 can provide communication services to communication node 220 using one or more beams.

[0082] The communication node 220 can perform communication (e.g., downlink communication or uplink communication) with the satellite 211 using 4G communication technology, 5G communication technology, and / or 6G communication technology. The communication between the satellite 211 and the communication node 220 can be performed using the NR-Uu interface or the 6G-Uu interface. When DC is supported, the communication node 220 can be connected to other base stations (e.g., base stations supporting 4G, 5G, and / or 6G functions) and the satellite 211, and can perform DC operations based on the technologies defined in the 4G, 5G, and / or 6G technical specifications.

[0083] The gateway 230 may be located at a ground location, a feed link may be established between the satellite 211 and the gateway 230, and a feed link may be established between the satellite 212 and the gateway 230. The feed link may be a radio link. When an ISL is not established between the satellite 211 and the satellite 212, a feed link between the satellite 211 and the gateway 230 may be established compulsorily. The communication between each of the satellite 211 and the satellite 212 and the gateway 230 may be performed based on an NR-Uu interface, a 6G-Uu interface, or an SRI. The gateway 230 may be connected to a data network 240.

[0084] like Figure 2b and Figure 2c As shown in the exemplary embodiment of FIG. 2 , a “core network” may exist between gateway 230 and data network 240 .

[0085] Figure 2b is a conceptual diagram showing a fourth exemplary embodiment of a non-terrestrial network, Figure 2c is a conceptual diagram illustrating a fifth exemplary embodiment of a non-terrestrial network.

[0086] like Figure 2b and Figure 2c As shown, the gateway can be connected to the core network, and the core network can be connected to the data network. The core network can support 4G communication technology, 5G communication technology and / or 6G communication technology. For example, the core network may include AMF, UPF, SMF, etc. The communication between the gateway and the core network can be performed based on the NG-C / U interface or the 6G-C / U interface. The functions of the base station can be performed through the satellite. That is, the base station can be located on the satellite. The payload can be processed by the base station located on the satellite. Base stations located on different satellites can be connected to the same core network. A satellite can have one or more base stations. In Figure 2b In non-terrestrial networks, it may not be possible to establish ISLs between satellites. Figure 2c In non-terrestrial networks, ISLs between satellites can be established.

[0087] On the other hand, the composition Figure 1a , Figure 1b , Figure 2a , Figure 2b and / or Figure 2c The entities of the non-terrestrial network shown (eg, satellite, base station, UE, communication node, gateway, etc.) may be configured as follows: In the present invention, the entity may be referred to as a communication node.

[0088] Figure 3 is a block diagram illustrating a first exemplary embodiment of communication nodes constituting a non-terrestrial network.

[0089] like Figure 3 As shown, the communication node 300 may include at least one processor 310, a memory 320, and a transceiver 330 connected to a network to perform communication. In addition, the communication node 300 may further include an input interface device 340, an output interface device 350, a storage device 360, etc. The components included in the communication node 300 may be connected through a bus 370 to communicate with each other.

[0090] However, each component included in the communication node 300 may be connected to the processor 310 through a separate interface or a separate bus instead of the common bus 370. For example, the processor 310 may be connected to at least one of the memory 320, the transceiver 330, the input interface device 340, the output interface device 350, and the storage device 360 ​​through a dedicated interface.

[0091] The processor 310 may execute at least one instruction stored in at least one of the memory 320 and the storage device 360. The processor 310 may refer to a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which the method according to the exemplary embodiment of the present invention is executed. Each of the memory 320 and the storage device 360 ​​may be configured as at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory 320 may be configured with at least one of a read-only memory (ROM) and a random access memory (RAM).

[0092] On the other hand, a communication node that performs communication in a communication network (eg, a non-terrestrial network) may be configured as follows. Figure 4 The communication nodes shown may be Figure 3 A specific exemplary embodiment of a communication node is shown.

[0093] Figure 4 is a block diagram illustrating a first exemplary embodiment of a communication node performing communications.

[0094] like Figure 4As shown, each of the first communication node 400a and the second communication node 400b can be a base station or a UE. The first communication node 400a can send a signal to the second communication node 400b. The transmission processor 411 included in the first communication node 400a can receive data (e.g., data unit) from the data source 410. The transmission processor 411 can receive control information from the controller 416. 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).

[0095] The transmit processor 411 may generate data symbols by performing processing operations on data (e.g., encoding operations, symbol mapping operations, etc.). The transmit processor 411 may generate control symbols by performing processing operations on control information (e.g., encoding operations, symbol mapping operations, etc.). In addition, the transmit processor 411 may generate synchronization / reference symbols for synchronization signals and / or reference signals.

[0096] The Tx MIMO processor 412 may perform spatial processing operations (e.g., precoding operations) on data symbols, control symbols, and / or synchronization / reference symbols. The output (e.g., symbol stream) of the Tx MIMO processor 412 may be provided to a modulator (MOD) included in the transceiver 413a to the transceiver 413t. The modulator may generate modulation symbols by performing processing operations on the symbol stream, and may generate signals by performing additional processing operations (e.g., analog conversion operations, amplification operations, filtering operations, up-conversion operations, etc.) on the modulation symbols. The signals generated by the modulators of the transceivers 413a to the transceivers 413t may be transmitted through the antennas 414a to the antennas 414t.

[0097] The signal transmitted by the first communication node 400a can be received at the antenna 464a to the antenna 464r of the second communication node 400b. The signal received at the antenna 464a to the antenna 464r can be provided to the demodulator (DEMOD) included in the transceiver 463a to the transceiver 463r. The demodulator (DEMOD) can obtain samples by performing processing operations (e.g., filtering operations, amplification operations, down-conversion operations, digital conversion operations, etc.) on the signal. The demodulator can perform additional processing operations on the samples to obtain symbols. The MIMO detector 462 can perform MIMO detection operations on the symbols. The receiving processor 461 can perform processing operations (e.g., deinterleaving operations, decoding operations, etc.) on the symbols. The output of the receiving processor 461 can be provided to the data sink 460 and the controller 466. For example, data can be provided to the data sink 460, and control information can be provided to the controller 466.

[0098] On the other hand, the second communication node 400b can send a signal to the first communication node 400a. The transmission processor 468 included in the second communication node 400b can receive data (e.g., data unit) from the data source 467, and perform processing operations on the data to generate data symbols. The transmission processor 468 can receive control information from the controller 466, and perform processing operations on the control information to generate control symbols. In addition, the transmission processor 468 can generate reference symbols by performing processing operations on reference signals.

[0099] The Tx MIMO processor 469 may perform spatial processing operations (e.g., precoding operations) on data symbols, control symbols, and / or reference symbols. The output (e.g., symbol stream) of the Tx MIMO processor 469 may be provided to a modulator (MOD) included in the transceiver 463a to the transceiver 463t. The modulator may generate modulation symbols by performing processing operations on the symbol stream, and may generate signals by performing additional processing operations (e.g., analog conversion operations, amplification operations, filtering operations, up-conversion operations) on the modulation symbols. The signals generated by the modulators of the transceivers 463a to the transceivers 463t may be transmitted via the antennas 464a to the antennas 464t.

[0100] The signal transmitted by the second communication node 400b may be received at the antenna 414a to the antenna 414r of the first communication node 400a. The signal received at the antenna 414a to the antenna 414r may be provided to a demodulator (DEMOD) included in the transceiver 413a to the transceiver 413r. The demodulator may obtain samples by performing a processing operation (e.g., a filtering operation, an amplification operation, a down-conversion operation, a digital conversion operation) on the signal. The demodulator may perform additional processing operations on the samples to obtain symbols. The MIMO detector 420 may perform a MIMO detection operation on the symbols. The receiving processor 419 may perform a processing operation (e.g., a deinterleaving operation, a decoding operation, etc.) on the symbols. The output of the receiving processor 419 may be provided to the data sink. 418 and controller 416. For example, data may be provided to data sink 418 and control information may be provided to controller 416.

[0101] Memory 415 and storage 465 may store data, control information and / or program codes. Scheduler 417 may perform scheduling operations for communications. Figure 4 The processors 411, 412, 419, 461, 468, 469 and the controllers 416 and 466 shown may be Figure 3The processor 310 shown may be used to execute the methods described in the present invention.

[0102] Figure 5a is a block diagram illustrating a first exemplary embodiment of a transmit path, Figure 5b is a block diagram illustrating a first exemplary implementation of a receive path.

[0103] like Figure 5a and Figure 5b As shown, the transmission path 510 can be implemented in a communication node that transmits a signal, and the receiving path 520 can be implemented in a communication node that receives a signal. The transmission path 510 may include a channel coding and modulation block 511, a serial-to-parallel (S to P) block 512, an N-point inverse fast Fourier transform (IFFT) block 513, a parallel-to-serial (P to S) block 514, a cyclic prefix (CP) adding block 515 and an up-converter (UC) 516. The receiving path 520 may include a down-converter (DC) 521, a CP deletion block 522, an S to P block 523, an N-point FFT block 524, a P to S block 525 and a channel decoding and demodulation block 526. Here, N may be a natural number.

[0104] In the transmission path 510, the information bits may be input to the channel coding and modulation block 511. The channel coding and modulation block 511 may perform coding operations (e.g., low-density parity check (LDPC) coding operations, polar coding operations, etc.) and modulation operations (e.g., quadrature phase shift keying (OPSK), quadrature amplitude modulation (QAM), etc.) on the information bits. The output of the channel coding and modulation block 511 may be a modulation symbol sequence.

[0105] The S to P block 512 may convert the frequency domain modulation symbols into parallel symbol streams to generate N parallel symbol streams. N may be an IFFT size or an FFT size. The N-point IFFT block 513 may generate a time domain signal by performing an IFFT operation on the N parallel symbol streams. The P to S block 514 may convert the output (e.g., parallel signals) of the N-point IFFT block 513 into a serial signal to generate a serial signal.

[0106] The CP adding block 515 may insert the CP into the signal. The UC 516 may up-convert the frequency of the output of the CP adding block 515 to a radio frequency (RF) frequency. In addition, the output of the CP adding block 515 may be filtered in the baseband before up-conversion.

[0107] The signal transmitted from the transmission path 510 may be input to the reception path 520. The operation in the reception path 520 may be an operation opposite to the operation in the transmission path 510. The DC 521 may down-convert the frequency of the received signal to the baseband frequency. The CP removal block 522 may remove the CP from the signal. The output of the CP removal block 522 may be a serial signal. The S to P block 523 may convert the serial signal into a parallel signal. The N-point FFT block 524 may generate N parallel signals by performing an FFT algorithm. The P to S block 525 may convert the parallel signal into a modulation symbol sequence. The channel decoding and demodulation block 526 may perform a demodulation operation on the modulation symbol, and may recover the data by performing a decoding operation on the result of the demodulation operation.

[0108] exist Figure 5a and Figure 5b In the present invention, discrete Fourier transform (DFT) and inverse DFT (IDFT) can be used to replace FFT and IFFT. Figure 5a and Figure 5b Each of the blocks (eg, components) in the embodiment may be implemented by at least one of hardware, software, or firmware. Figure 5a and Figure 5b Some blocks in the can be implemented by software, and other blocks can be implemented by hardware or a combination of hardware and software. Figure 5a and Figure 5b In the , a block can be subdivided into multiple blocks, multiple blocks can be integrated into one block, some blocks can be omitted, and blocks that support other functions can be added.

[0109] On the other hand, the NTN reference scenario may be defined as shown in Table 1 below.

[0110] [Table 1]

[0111] NTN shown in Figure 1 NTN shown in Figure 2 GEO Scenario A Scenario B LEO (Steering Beam) Scenario C1 Scenario D1 LEO (beam that moves with the satellite) Scenario C2 Scene D2

[0112] when Figure 1a and / or Figure 1b When the satellite 110 in the NTN shown is a GEO satellite (e.g., a GEO satellite supporting transparency functionality), this may be referred to as "Scenario A". Figure 2a , Figure 2b and / or Figure 2cWhen satellite 211 and satellite 212 in the NTN shown are GEO satellites (eg, GEOs supporting regeneration functionality), this may be referred to as "scenario B".

[0113] when Figure 1a and / or Figure 1b When the satellite 110 in the NTN shown is a LEO satellite with a steerable beam, this may be referred to as "Scenario C1". Figure 1a and / or Figure 1b When the satellite 110 in the NTN shown is a LEO satellite with a beam that moves with the satellite, this may be referred to as "Scenario C2". Figure 2a , Figure 2b and / or Figure 2c When satellite 211 and satellite 212 in the NTN shown are LEO satellites with steerable beams, this may be referred to as "Scenario D1". Figure 2a , Figure 2b and / or Figure 2c When satellite 211 and satellite 212 in the NTN shown are LEO satellites with beams that move with the satellites, this may be referred to as "scenario D2".

[0114] Parameters for the NTN reference scenario defined in Table 1 may be defined as shown in Table 2 below.

[0115] [Table 2]

[0116]

[0117]

[0118] In addition, in the scenario defined in Table 1, the delay constraint may be defined as shown in Table 3 below.

[0119] [Table 3]

[0120]

[0121] Figure 6a is a conceptual diagram showing a first exemplary embodiment of a protocol stack for a user plane in a non-terrestrial network based on a transparent payload, Figure 6b is a conceptual diagram illustrating a first exemplary embodiment of a protocol stack of a control plane in a non-terrestrial network based on a transparent payload.

[0122] like Figure 6a and Figure 6b As shown, user data can be sent and received between the UE and the core network (e.g., UPF), and control data (e.g., control information) can be sent and received between the UE and the core network (e.g., AMF). Each of the user data and the control data can be sent and received via a satellite and / or a gateway. Figure 6aThe protocol stack of the user plane shown can be applied identically or similarly to a 6G communication network. Figure 6b The control plane protocol stack shown can be applied identically or similarly to a 6G communication network.

[0123] Figure 7a is a conceptual diagram illustrating a first exemplary embodiment of a protocol stack for a user plane in a non-terrestrial network based on a regenerative payload, Figure 7b is a conceptual diagram illustrating a first exemplary embodiment of a protocol stack for a control plane in a non-terrestrial network based on a regenerative payload.

[0124] like Figure 7a and Figure 7b As shown, each of user data and control data (e.g., control information) can be sent and received through an interface between a UE and a satellite (e.g., a base station). User data can refer to a user protocol data unit (PDU). A protocol stack of a satellite radio interface (SRI) can be used to send and receive user data and / or control data between a satellite and a gateway. User data can be sent and received between a satellite and a core network through a general packet radio service (GPRS) tunneling protocol (GTP)-U tunnel.

[0125] On the other hand, in a non-terrestrial network, the base station may transmit system information (e.g., SIB19) including satellite assistance information for NTN access. The UE may receive the system information (e.g., SIB19) from the base station, identify the satellite assistance information included in the system information, and perform communication (e.g., non-terrestrial communication) based on the satellite assistance information. SIB19 may include the information elements defined in Table 4 below.

[0126] [Table 4]

[0127]

[0128] The NTN-Config defined in Table 4 may include the information elements defined in Table 5 below.

[0129] [Table 5]

[0130]

[0131]

[0132] The EphemerisInfo defined in Table 5 may include the information elements defined in the following Table 6.

[0133] [Table 6]

[0134]

[0135] In a communication system, a physical uplink shared channel (PUSCH) demodulation reference signal (DMRS) bundling operation may be supported. PUSCH DMRS may refer to a DMRS used to demodulate PUSCH. When PUSCH DMRS bundling operation is supported, joint channel estimation for bundled PUSCH DMRS may be performed. In addition, when PUSCH DMRS bundling operation is supported, communication coverage may be improved.

[0136] In a communication system (e.g., NTN), due to the limitation of the maximum transmission power of the terminal and / or the distance between the terminal and the satellite, the terminal can perform repeated uplink transmission. In other words, the terminal can repeatedly send uplink data. In order to provide sufficient transmission reliability, the number of repetitions of a transport block (TB) can be increased. In order to improve communication coverage, the maximum number of repetitions of PUSCH can be set to 32. A time domain window (TDW) that meets power consistency and / or phase continuity requirements can be defined. Joint channel estimation of continuous PUSCHs (e.g., repeatedly transmitted PUSCHs) within the TDW may be feasible. Bundled PUSCH DMRS can be used for joint channel estimation.

[0137] Joint channel estimation can be performed ideally in an environment where the channel between the terminal and the base station does not change and the transmission power of the terminal is well controlled. In non-terrestrial networks, the rapid movement of satellites may cause Doppler shift and / or timing drift. Timing drift may refer to changes in the propagation delay of a physical signal. Doppler shift and / or timing drift may affect the path loss magnitude and / or signal phase in a wireless channel. In this case, the TDW that satisfies power consistency and / or phase continuity may be reduced. In other words, when an event occurs that does not maintain power consistency and / or phase continuity, the actual TDW may terminate. Accordingly, the gain of the joint channel estimation may be reduced.

[0138] Due to satellite movement in non-terrestrial networks, time offset (e.g., time offset between downlink time and uplink time) may change rapidly, and time offset can be controlled by timing advance control (TAC). In other words, the base station can control the time offset based on TAC so that the uplink signal / channel of the terminal arrives at the base station according to the target timing advance (TA). However, when the transmission timing of the terminal changes due to TAC, power consistency and / or phase continuity may not be maintained. In other words, TDW may not be maintained. In this case, the gain of joint channel estimation may be reduced. In the present invention, uplink signal / channel may refer to uplink signal and / or uplink channel. Depending on the context, the uplink signal may be interpreted as including both uplink signal and uplink channel. Depending on the context, the uplink channel may be interpreted as including both uplink signal and uplink channel.

[0139] In non-terrestrial networks, timing offset changes and / or phase discontinuities may occur due to the movement of satellites. By compensating for timing offset changes and / or phase discontinuities, the size of the TDW can be maximized. PUSCH DMRS bundling operations and / or repeated PUSCH transmission operations can be performed within the TDW. In this case, the performance of joint channel estimation at the receiving node (e.g., base station, satellite, or terminal) can be improved.

[0140] Figure 8 is a conceptual diagram of a first exemplary embodiment illustrating a change in a distance between a satellite and a terminal according to movement (eg, position) of the satellite and / or the terminal during TDW in a non-terrestrial network based on a regenerative payload.

[0141] like Figure 8 As shown, in case 2, the distance between the terminal and the satellite may increase over time, and a negative frequency shift may occur due to the Doppler effect. In case 3, the distance between the terminal and the satellite may decrease over time, and a positive frequency shift may occur due to the Doppler effect. In case 1, the change in the distance between the terminal and the satellite over time may not be significant. The change in the distance between the terminal and the satellite in case 1 (e.g., the distance change in the wireless channel) and / or the frequency shift caused by the Doppler effect may not be greater than the frequency shift in case 2 and / or case 3.

[0142] Fig. 9 is a conceptual diagram of a first exemplary embodiment illustrating a change in a distance between a satellite and a terminal according to movement (eg, position) of the satellite and / or the terminal during TDW in a transparent payload-based non-terrestrial network.

[0143] like Fig. 9 As shown, the distance between the terminal and the satellite and / or the distance between the gateway (e.g., a ground base station) and the satellite can change according to the movement of the satellite. In other words, the length of the service link and / or the length of the feeder link can change. Changes in the length of the service link and / or the feeder link may affect timing drift and / or Doppler shift. Timing drift can be a change in a specified time offset.

[0144] The present invention can be applied to Figure 8 Example embodiments of (e.g., non-terrestrial networks based on regenerative payloads) and / or Fig. 9 The variation of the distance between the terminal and the satellite (eg, the distance of the service link) over time t can be defined as L S The distance between the gateway (e.g., ground base station) and the satellite (e.g., ground base station) (e.g., the distance of the feeder link) over time t can be defined as L F (t) L S (t) and L F The sum of (t) can be defined as L SF (t) L SF The rate of change of (t) over time can be defined as A communication node (e.g., a base station, a satellite, or a terminal) can be based on The change in timing offset and / or frequency shift (eg, Doppler shift) may be predicted, and a pre-compensation operation and / or a post-compensation operation may be performed on the predicted change in timing offset and / or the predicted frequency shift.

[0145] According to the pre-compensation operation and / or the post-compensation operation, the receiving performance can be improved. In addition, the TDW can be maintained, and the gain of the joint channel estimation in the TDW can be enhanced. In the signal / channel transmission and reception process, one of the pre-compensation operation and the post-compensation operation can be applied. As another method, both the pre-compensation operation and the post-compensation operation can be applied in the signal / channel transmission and reception process. The pre-compensation operation can refer to the pre-correction operation. The post-compensation operation can refer to the post-correction operation.

[0146] [Method 1] Pre-compensation operation for timing drift and / or common phase shift

[0147] In a non-terrestrial network, a terminal may perform repeated PUSCH transmissions. When performing repeated PUSCH transmissions, the physical length of a wireless channel (e.g., a service link and / or a feeder link) may change due to the movement of a satellite. Due to the change in the length of the wireless channel, the length of the TDW for performing repeated PUSCH transmissions may decrease. In other words, due to the change in the length of the wireless channel, power consistency and / or phase continuity may not be maintained, and in this case, the TDW (e.g., actual TDW) may terminate. Due to the change in the length of the wireless channel and / or the termination of the actual TDW, the performance of the joint channel estimation may be reduced. In order to solve the above problems (e.g., the reduction in the length of the actual TDW and / or the reduction in the performance of the joint channel estimation), compensation operations for timing drift (e.g., timing offset) and / or phase shift (e.g., phase offset) may be performed while performing repeated PUSCH transmissions.

[0148] The transmission timing of PUSCH can be adjusted by TAC. In this case, the gain of joint channel estimation may be reduced because power consistency and / or phase continuity may not be maintained. In the present invention, it can be assumed that the timing of PUSCH transmissions to which joint channel estimation is applied is the same. In the present invention, TAC-based timing compensation may not be applied to PUSCH transmissions.

[0149] Fig.10 is a conceptual diagram illustrating a first exemplary embodiment of timing drift of PUSCH transmission in a non-terrestrial network.

[0150] like Fig.10 As shown, the terminal may perform repeated PUSCH transmission. For example, the terminal may repeat PUSCH transmission six times. Case 1 may correspond to Figure 8 Case 1 shown and / or Fig. 9 Case 1 is shown. Case 2 can correspond to Figure 8 Case 2 shown and / or Fig. 9 Case 2 is shown. Case 3 can correspond to Figure 8 Case 3 shown and / or Fig. 9 The situation shown is 3. Fig.10In an exemplary embodiment, the timing may refer to the reception timing of the PUSCH at a base station (e.g., a satellite). In Case 1, Case 2, and Case 3, the timing of the first PUSCH transmission may be aligned. For example, the timing of the first PUSCH transmission may be aligned with a time slot boundary. The timing (s) of (multiple) PUSCH transmissions after the first PUSCH transmission may not be aligned. For example, in Case 2 and Case 3, the timing of the PUSCH transmissions after the first PUSCH transmission may not be aligned with a time slot boundary. The present invention can be applied not only when the timing of the first PUSCH transmission is aligned, but also when the timing of the first PUSCH transmission is not aligned.

[0151] - Case 1: Since the distance between the satellite and the terminal does not change significantly with the movement of the satellite, the timing drift may be small.

[0152] - Case 2: Since the distance between the satellite and the terminal increases as the satellite moves, the reception timing of the PUSCH (eg, PUSCH transmission) at the base station (eg, satellite) may be delayed over time. In other words, timing drift may occur.

[0153] - Case 3: Since the distance between the satellite and the terminal decreases as the satellite moves, the reception timing of the PUSCH (eg, PUSCH transmission) at the base station (eg, satellite) may advance over time. In other words, timing drift may occur.

[0154] [Method 1-1] Precompensation operation in the frequency domain

[0155] exist Fig.10 In the case 1 shown, since the timing drift is small, the channel estimation result for each time slot performing PUSCH transmission can be almost the same. In this case, joint channel estimation can be performed, and the accuracy of channel estimation can be improved by joint channel estimation. Fig.10 In case 2 and / or case 3 shown, when repeated PUSCH transmission is performed, the timing offset may gradually increase, and accordingly, the gain of joint channel estimation by coherent combining may not be obtained. The timing offset may refer to the offset between the time slot boundary (e.g., subframe boundary) and the reception time (e.g., actual reception start time or predicted reception start time) of the PUSCH transmission at the base station (e.g., satellite). The timing offset may be estimated based on the distance between the base station (e.g., satellite) and the terminal.

[0156] The timing offset (e.g., the timing offset of the PUSCH transmission) may cause a phase shift of each subcarrier k in the frequency domain at the receiving node (e.g., the receiver). Here, k can be the subcarrier index. The phase shift change between adjacent subcarriers can be defined as Phase shift variation between adjacent subcarriers May be proportional to the timing offset.

[0157] A transmitting node (e.g., a transmitter) may predict the phase shift of a subcarrier caused by a timing offset of a transmission channel / signal and may pre-compensate the phase shift in a direction opposite to the predicted phase shift. The phase shift to be pre-compensated may be defined as and It can be defined as shown in the following equation 1. The transmitting node can use equation 1 to determine the phase shift

[0158] [Equation 1]

[0159]

[0160] In the present invention, a sending node may refer to a communication node that sends data (eg, a data unit or a data channel), and a receiving node may refer to a communication node that receives data (eg, a data unit or a data channel). It may refer to a phase shift difference between subcarriers (eg, adjacent subcarriers) caused by a timing offset at a specific time t (eg, a specific time slot or a specific symbol). It may be proportional to the timing offset at a specific time t (e.g., a specific time slot or a specific symbol). 0 It may refer to the position of a reference frequency (eg, a reference subcarrier). It can represent the phase shift at the reference frequency.

[0161] To perform a precompensation operation, a communication node (eg, a terminal, a base station, or a satellite) may use the following information elements.

[0162] - Information element 1: position k of the reference subcarrier 0

[0163] - Information element 2: Information about the phase to be precompensated at the reference subcarrier (e.g., the phase shift difference between the reference subcarrier and another subcarrier)

[0164] - Information element 3: timing offset or information corresponding to the timing offset

[0165] The reference subcarrier as information element 1 may be one of the uplink subcarriers. The base station (e.g., satellite) may notify the terminal of the position information of the reference subcarrier by signaling. The terminal may determine the position information of the reference subcarrier by signaling from the base station (e.g., satellite). In other words, the base station (e.g., satellite) may explicitly indicate the position of the reference subcarrier to the terminal. Alternatively, the position of the reference subcarrier may be implicitly indicated to the terminal. The terminal may determine the position of the reference subcarrier by an implicit method.

[0166] For example, the reference subcarrier may be a specific subcarrier within a resource block (RB) of the PUSCH allocated to the terminal. The specific subcarrier may be a subcarrier with the lowest frequency within the RB, a subcarrier with the highest frequency within the RB, or a subcarrier with a center frequency within the RB. In another example, the reference subcarrier may be a specific subcarrier within an activated bandwidth part (BWP) of the terminal. The specific subcarrier may be a subcarrier with the lowest frequency within the activated BWP, a subcarrier with the highest frequency within the activated BWP, or a subcarrier with a center frequency within the activated BWP. In another example, the reference subcarrier may be a specific subcarrier within the bandwidth of a carrier component. The specific subcarrier may be a subcarrier with the lowest frequency within the bandwidth of a carrier component, a subcarrier with the highest frequency within the bandwidth of a carrier component, or a subcarrier with a center frequency within the bandwidth of a carrier component.

[0167] Each of information element 2 and information element 3 may be time slot specific information or symbol specific information. Alternatively, each of information element 2 and information element 3 may be information specific to a time period (which is greater than a time slot). A base station (e.g., a satellite) may notify the terminal of information element 2 and / or information element 3 by signaling. The terminal may determine information element 2 and / or information element 3 by signaling from the base station. Alternatively, the terminal may estimate information element 2 and / or information element 3 without signaling from the base station.

[0168] Information element 3 may be determined per unit of a specific time period. The specific time period may be configured in units of symbols (e.g., OFDM symbols), time slots, or 1 millisecond (ms). The specific time period may include two or more time slots. The specific time period may be configured in various ways. The timing offset may be determined based on the distance between the terminal and the base station (e.g., a satellite). For example, based on the distance between the terminal and the base station (e.g., a satellite), the time at which a signal / channel sent from the terminal is received at the base station (e.g., a satellite) may be predicted, and the timing offset may be an offset between the predicted time and a synchronization reference time (e.g., a time slot boundary or a subframe boundary).

[0169] A base station (e.g., a satellite) may estimate the length of a service link and / or a feeder link based on the ephemeris information of the satellite, the location information of the terminal, and / or the location information of a ground base station. Based on the estimated length of the service link and / or the feeder link, the base station may predict a timing offset (e.g., information corresponding to the timing offset) and send the predicted timing offset to the terminal via signaling. The terminal may determine the timing offset (e.g., information corresponding to the timing offset) via signaling from the base station. Alternatively, the terminal may estimate the length of the service link and / or the feeder link based on the ephemeris information of the satellite, the location information of the terminal, and / or the location information of the ground base station. Based on the estimated length of the service link and / or the feeder link, the terminal may predict a timing offset (e.g., information corresponding to the timing offset). The terminal may send the predicted timing offset to the base station via signaling.

[0170] Fig.11 is a block diagram illustrating a first exemplary embodiment of a transmitting node performing a pre-compensation operation.

[0171] like Fig.11 As shown, in uplink communication, the transmitting node may be a terminal, and in downlink communication, the transmitting node may be a base station or a satellite. The transmitting node may generate modulation symbols by performing a modulation operation on the data. The transmitting node may perform a generation operation of a DMRS (e.g., a PUSCH DMRS). The transmitting node may perform a generation operation of a phase tracking reference signal (PTRS). The transmitting node may map the modulation symbols, DMRS, and / or PTRS to resources (e.g., time resources and frequency resources). Before performing an inverse fast Fourier transform (IFFT) operation in the frequency domain, the transmitting node may apply a phase shift (e.g., phase precompensation) to each subcarrier. The phase shift operation may be performed by a phase shifter included in the transmitting node.

[0172] For example, the sending node may predict based on information element 1, information element 2 and / or information element 3 In other words, the sending node can determine based on Equation 1 Alternatively, the receiving node (eg, a base station or a satellite) may predict based on information element 1, information element 2, and / or information element 3 In other words, the receiving node can determine based on Equation 1 The receiving node can notify the sending node through signaling The sending node can determine the The transmitting node may apply a phase shift to each subcarrier. In method 1-1, a phase shift (eg, phase precompensation) may be applied to each subcarrier.

[0173] [Method 1-2] Pre-compensation operation in the time domain

[0174] According to method 1-2, the performance degradation caused by timing drift (e.g., change in timing offset) and / or Doppler shift can be alleviated by utilizing common phase shift and / or cyclic frequency shift. Information element 1, information element 2, and / or information element 3 defined in method 1-1 can be used for method 1-2. The operation according to method 1-1 can be applied to method 1-2. The sending node can perform method 1-1 or method 1-2. Alternatively, the sending node can perform both method 1-1 and method 1-2. The receiving node (e.g., a base station or a satellite) can send information indicating that the sending node (e.g., a terminal) performs at least one of method 1-1 or method 1-2 through signaling. The sending node can perform method 1-1 and / or method 1-2 as indicated by the signaling from the receiving node.

[0175] Fig.12 is a block diagram illustrating a second exemplary embodiment of a transmitting node performing a pre-compensation operation.

[0176] like Fig.12 As shown, in uplink communication, the transmitting node may be a terminal, and in downlink communication, the transmitting node may be a base station or a satellite. The transmitting node may perform a modulation operation on the data to generate a modulation symbol. The transmitting node may perform a generation operation of a DMRS (e.g., a PUSCH DMRS). The transmitting node may perform a generation operation of a PTRS. The transmitting node may map the modulation symbols, DMRS, and / or PTRS to resources. The transmitting node may perform an IFFT operation in the frequency domain. Alternatively, before performing the IFFT operation in the frequency domain, the transmitting node may apply a phase shift (e.g., phase precompensation) to each subcarrier.

[0177] The transmitting node may perform an IFFT operation after performing a resource mapping operation or a phase shift operation, and may apply a cyclic shift and / or a common phase shift after performing the IFFT operation. In other words, a cyclic shift operation and / or a common phase shift operation may be performed between the IFFT operation and the CP addition operation. The cyclic shift operation may be performed by a cyclic shifter included in the transmitting node. The common phase shift operation may be performed by a common phase shifter included in the transmitting node. In the cyclic shift stage, the transmitting node (e.g., a cyclic shifter) may perform operations according to the following equation 2.

[0178] [Equation 2]

[0179] Y[n]=X[mod(n+n Δ ,N IFFT )]

[0180] X[n] may be the input value of the circular shifter. Y[n] may be the output value of the circular shifter. IFFT It can indicate the size of IFFT. Δ It may be a value obtained from a timing offset (e.g., a timing offset caused by the movement of a satellite). Δ Can be any integer. Δ It may be set for each symbol (eg, OFDM symbol), a time slot, or a time period greater than a time slot.

[0181] The base station (eg, satellite) may predict n based on the satellite's ephemeris information, the terminal's location information, and / or the ground base station's location information. Δ , and the predicted n can be signaled Δ The terminal can determine n through the signaling of the base station. Δ Alternatively, the terminal may predict n based on the satellite's ephemeris information, the terminal's location information, and / or the location information of the ground base station. Δ The terminal can send the predicted n Δ Send to the base station.

[0182] For example, when n Δ =5 and n=0, it can be derived that Y[0]=X[5]. In this case, the transmitting node can apply a cyclic shift corresponding to five samples. In other words, in the time domain, the transmission timing of the signal / channel can be advanced by five samples. In this case, the transmission delay of five samples can be compensated. The sample can correspond to a symbol, a time slot, or a time period greater than a time slot.

[0183] exist Figures 8 to 10 In the exemplary embodiment of FIG. 1 , signal distortion (e.g., phase discontinuity) may occur due to the movement of the satellite (e.g., Doppler shift). In this case, the performance of the joint channel estimation may be degraded. To reduce signal distortion, a Fig.12 The common phase shift is shown.

[0184] The common phase shifter may uniformly shift the phase of all input signals within a symbol (e.g., a single OFDM symbol) or within a time slot. The magnitude of the phase shift applied by the common phase shifter may be determined taking into account Doppler shift and / or timing drift (e.g., timing offset). When a common phase shift is applied, the problem of phase discontinuity in repeated PUSCH transmissions over multiple time slots may be resolved.

[0185] The common phase shift operation may be performed immediately before the CP adding operation. Alternatively, the common phase shift operation may be performed at any time after the resource mapping operation. The common phase shift operation may be performed by a phase shifter (or, a complex multiplier) different from the existing phase shifter.

[0186] [Method 2] Post-compensation operation for timing drift and / or common phase shift

[0187] Method 2 can be applied to the following situations.

[0188] - During repeated PUSCH transmissions, the terminal may support PUSCH DMRS bundling operation.

[0189] - During a timeslot period (eg, TDW) in which the PUSCH DMRS bundling operation is applied, TA update may not be performed.

[0190] - During one TDW, the terminal may or may not perform pre-compensation for timing drift and / or phase shift.

[0191] Timing drift can be considered as a timing offset that changes linearly over time (e.g., within a sufficiently short period of time) and a Doppler shift (e.g., frequency shift) that occurs constantly. A receiving node (e.g., a base station or a satellite) can perform a post-compensation operation on the timing offset and / or Doppler shift of a signal / channel received from a sending node (e.g., a terminal).

[0192] If the receiving node supports post-compensation operation, signal distortion of terminals that do not support DMRS bundling (eg, PUSCH DMRS bundling) can also be compensated. In the present invention, an area may refer to coverage (eg, communication coverage) served by a single beam, a single cell, or a single satellite.

[0193] [Method 2-1] Post-compensation operation for each region in the frequency domain

[0194] In non-terrestrial networks, a satellite may include multiple cells, and each cell may utilize multiple beams to perform communications. Services for terminals located in adjacent areas (e.g., in the same area) may be provided by the same beam, the same cell, or the same satellite. It may be assumed that terminals located in the same area have similar timing drift characteristics. Fig.10 In an exemplary embodiment, the timing drift characteristic may refer to the difference between the synchronization reference time (e.g., time slot boundary) and the reception time of the PUSCH transmission (e.g., predicted reception start time or actual reception start time), or a characteristic corresponding to the difference (e.g., a characteristic similar to the difference).

[0195] Fig.13 is a block diagram illustrating a first exemplary implementation of a receiving node that performs a post-compensation operation.

[0196] like Fig.13As shown, in uplink communication, the receiving node may be a base station or a satellite, and in downlink communication, the receiving node may be a terminal. The receiving node may receive a signal / channel from a transmitting node and perform a CP removal operation on the signal / channel. The receiving node may perform an FFT operation on the result of the CP removal operation. The receiving node may apply a phase shift to the result of the FFT operation. The receiving node may perform a resource demapping operation on the result of the phase shift operation. The phase shift operation may be applied to each subcarrier (e.g., frequency point (tone)). When the phase is compensated for each subcarrier of the received signal, the signal distortion caused by the timing drift may be offset.

[0197] The receiving node may determine the Alternatively, the receiving node may determine based on an equation different from Equation 1 And apply the determined amount Here, k may represent a subcarrier index (eg, a frequency point index). In equation 1, other parameters (eg, k 0 and ) can be set to any value. Based on the information about the timing drift of the terminals in the area (e.g., the timing drift characteristics), other parameters (e.g., k 0 and ) is an optimal value (or a value corresponding to the optimal value). Alternatively, other parameters (e.g., k 0 and ).

[0198] Although the terminals in an area may have different timing drift characteristics, it can be assumed that the terminals in a sufficiently small area have similar timing drift characteristics. Therefore, in method 2-1, it can be assumed that all terminals in the area have the same timing drift, and the timing drift can be applied across the entire bandwidth. A single timing drift can be a representative timing drift for all terminals in the area.

[0199] The transmitting node may support a pre-compensation operation, and the receiving node may support a post-compensation operation (e.g., a post-compensation operation according to method 2-1). In this case, the compensation operation for the timing offset and / or phase shift may be redundantly performed at both the transmitting node and the receiving node. If the compensation operation is redundantly performed at both the transmitting node and the receiving node, the receiving performance may be reduced. In order to prevent this problem, the following signaling operation may be performed. The signaling operation may be performed for the terminal within the area. The signaling operation may be at least one of an SI signaling operation, an RRC signaling operation, a MAC signaling operation, or a PHY signaling operation.

[0200] -Signaling operation 1: A transmitting node (eg, a terminal) may transmit information indicating whether DMRS bundling is supported and / or information indicating whether a precompensation operation is supported to a receiving node (eg, a base station, a satellite).

[0201] -Signaling operation 2: The receiving node (e.g., base station, satellite) may send information indicating enabling or disabling of the post-compensation operation to the sending node (e.g., terminal). The receiving node (e.g., base station, satellite) may send information indicating whether to perform the pre-compensation operation at the sending node (e.g., terminal) to the sending node. If the sending node does not support (e.g., perform) the pre-compensation operation, the post-compensation operation may be enabled. If the sending node supports (e.g., performs) the pre-compensation operation, the post-compensation operation may be disabled.

[0202] -Signaling operation 3: The receiving node (e.g., base station, satellite) may send a compensation value (e.g., correction value) for a post-compensation operation and / or a pre-compensation operation, information corresponding to the compensation value (e.g., similar information), values ​​of corresponding parameters defined in Equation 1, and / or information corresponding to the corresponding parameter values ​​(e.g., similar information) to a sending node (e.g., terminal).

[0203] [Method 2-2] RB / terminal-specific post-compensation operation in the frequency domain

[0204] Method 2-2 may be the same as method 2-1. However, the phase shift operation in method 2-2 may be different from the phase shift operation in method 2-1.

[0205] In method 2-1, the post-compensation operation (eg, post-compensation for phase shift) for all terminals in the area may be determined based on a single timing drift characteristic. In other words, the equation for the post-compensation operation may be commonly applied to all terminals and all RBs.

[0206] In method 2-2, the post-compensation operation may be performed based on a different equation for each RB or based on the same equation for different RBs. For example, if RB 0 to RB 7 are allocated to terminal 1 and RB 8 to RB 15 are allocated to terminal 2, the equation for the post-compensation operation for terminal 1 may be different from the equation for terminal 2. If some RBs are allocated to multiple users (for example, in the case of multi-user (MU)-MIMO), a phase shift operation may be performed based on a selected timing drift characteristic among the timing drift characteristics of the multiple users or a combination of the timing drift characteristics of the multiple users.

[0207] The transmitting node may support a pre-compensation operation, and the receiving node may support a post-compensation operation (e.g., a post-compensation operation according to method 2-2). In this case, the compensation operation for the timing offset and / or phase shift may be redundantly performed at both the transmitting node and the receiving node. If the compensation operation is redundantly performed at both the transmitting node and the receiving node, the receiving performance may be reduced. In order to prevent this problem, the following signaling operation may be performed. The signaling operation may be performed for the terminal within the area. The signaling operation may be at least one of an SI signaling operation, an RRC signaling operation, a MAC signaling operation, or a PHY signaling operation.

[0208] -Signaling operation 1: A transmitting node (eg, a terminal) may transmit information indicating whether DMRS bundling is supported and / or information indicating whether a precompensation operation is supported to a receiving node (eg, a base station, a satellite).

[0209] -Signaling operation 2: The receiving node (e.g., base station, satellite) may send information indicating enabling or disabling of the post-compensation operation to the sending node (e.g., terminal). The receiving node (e.g., base station, satellite) may send information indicating whether to perform the pre-compensation operation at the sending node (e.g., terminal) to the sending node. If the sending node does not support (e.g., perform) the pre-compensation operation, the post-compensation operation may be enabled. If the sending node supports (e.g., performs) the pre-compensation operation, the post-compensation operation may be disabled.

[0210] -Signaling operation 3: The receiving node (e.g., base station, satellite) may send a compensation value (e.g., correction value) for a post-compensation operation and / or a pre-compensation operation, information corresponding to the compensation value (e.g., similar information), values ​​of corresponding parameters defined in Equation 1, and / or information corresponding to the corresponding parameter values ​​(e.g., similar information) to a sending node (e.g., terminal).

[0211] [Method 2-3] RB / terminal specific post-compensation operation in the time domain

[0212] A combination of method 2-3 and method 2-1 or a combination of method 2-3 and method 2-2 may be performed. Alternatively, method 2-3 may be performed independently of method 2-1 and / or method 2-2.

[0213] Fig.14 is a block diagram illustrating a second exemplary embodiment of a receiving node that performs a post-compensation operation.

[0214] like Fig.14 As shown, in uplink communication, the receiving node may be a base station or a satellite, and in downlink communication, the receiving node may be a terminal. The receiving node may receive a signal / channel from a transmitting node and perform an adaptive CP deletion operation on the signal / channel. The receiving node may perform a common phase shift operation on the result of the adaptive CP deletion operation. The receiving node may perform an FFT operation on the result of the common phase shift operation. The receiving node may perform a resource demapping operation on the result of the FFT operation.

[0215] Method 2-3 may be similar to method 1-2. Below, the difference between method 2-3 and method 1-2 will be described. Except for the difference, the operations in method 2-3 and method 1-2 may be the same.

[0216] In method 2-3, instead of the general CP deletion operation, an adaptive CP deletion operation may be performed. The adaptive CP deletion operation may cover the general CP deletion operation.

[0217] Fig.15a is a conceptual diagram showing a first exemplary embodiment of a general CP deletion operation, Fig.15b is a conceptual diagram illustrating a first exemplary embodiment of an adaptive CP deletion operation.

[0218] like Fig.15a As shown, in a general CP deletion operation, a symbol (e.g., OFDM symbol) may be extracted from a fixed period of samples of a received signal. In other words, the Nth OFDM symbol may be extracted from samples within a period of [CP_start(N+1)-NFFT-offset, CP_start(N+1)-1-offset] for a constant offset. Here, CP_start(N+1) may represent the starting sample index of the CP of the (N+1)th OFDM symbol, NFFT may represent the FFT size, and offset may be any positive value.

[0219] like Fig.15b As shown, in the adaptive CP deletion operation, a symbol-specific adaptive offset can be used. By performing the adaptive CP deletion operation, signal distortion caused by timing drift can be reduced.

[0220] Reference again Fig.14, the common phase shift operation may also be performed after the FFT operation. Alternatively, the common phase shift operation may be performed at any time point. The symbol-specific adaptive offset may be determined based on one of the timing drift characteristics (eg, the representative timing drift characteristic) of the terminals in the region.

[0221] The transmitting node may support a pre-compensation operation, and the receiving node may support a post-compensation operation (e.g., a post-compensation operation according to method 2-3). In this case, the compensation operation for the timing offset and / or phase shift may be redundantly performed at both the transmitting node and the receiving node. If the compensation operation is redundantly performed at both the transmitting node and the receiving node, the receiving performance may be reduced. In order to prevent this problem, the following signaling operation may be performed. The signaling operation may be performed for the terminal within the area. The signaling operation may be at least one of an SI signaling operation, an RRC signaling operation, a MAC signaling operation, or a PHY signaling operation.

[0222] -Signaling operation 1: A transmitting node (eg, a terminal) may transmit information indicating whether DMRS bundling is supported and / or information indicating whether a precompensation operation is supported to a receiving node (eg, a base station, a satellite).

[0223] -Signaling operation 2: The receiving node (e.g., base station, satellite) may send information indicating enabling or disabling of the post-compensation operation to the sending node (e.g., terminal). The receiving node (e.g., base station, satellite) may send information indicating whether to perform the pre-compensation operation at the sending node (e.g., terminal) to the sending node. If the sending node does not support (e.g., perform) the pre-compensation operation, the post-compensation operation may be enabled. If the sending node supports (e.g., performs) the pre-compensation operation, the post-compensation operation may be disabled.

[0224] -Signaling operation 3: The receiving node (e.g., base station, satellite) may send information about the timing drift characteristics for the adaptive CP deletion operation to the sending node (e.g., terminal). For example, the information about the timing drift characteristics may indicate that the CP is increased or decreased by a certain amount τ per millisecond on average. Δ microsecond offset to extract OFDM symbols.

[0225] The above methods (e.g., method 1, method 1-1, method 1-2, method 2, method 2-1, method 2-2, and / or method 2-3) may be used in combination. The above methods (e.g., method 1, method 1-1, method 1-2, method 2, method 2-1, method 2-2, and / or method 2-3) may be used selectively. A combination of the above methods (e.g., method 1, method 1-1, method 1-2, method 2, method 2-1, method 2-2, and / or method 2-3) may be used. In the above methods (e.g., method 1, method 1-1, method 1-2, method 2, method 2-1, method 2-2, and / or method 2-3), the method used in the signal / channel transmission and reception process may be selected by a transmitting node (e.g., a terminal) and / or a receiving node (e.g., a base station, a satellite), and information about the selected method may be sent to other communication nodes via signaling.

[0226] The operation of the method according to the exemplary embodiment of the present invention can be implemented as a computer-readable program or code in a computer-readable recording medium. The computer-readable recording medium may include a recording device of all types having data that can be read by a computer system. In addition, the computer-readable recording medium can store and execute programs or codes, which can be distributed in a computer system connected via a network and read by a computer in a distributed manner.

[0227] Computer readable recording media may include hardware devices specifically configured to store and execute program instructions, such as ROM, RAM or flash memory. Program instructions may include not only machine language codes created by a compiler, but also high-level language codes that can be executed by a computer using an interpreter.

[0228] Although some aspects of the present invention have been described in the context of a device, these aspects may indicate the corresponding description according to the method, and a block or device may correspond to the step of the method or the feature of the step. Similarly, the aspects described in the context of the method may be represented as the feature of a corresponding block or project or a corresponding device. Some or all steps of the method may be performed by (or using) a hardware device such as a microprocessor, a programmable computer or an electronic circuit. In some embodiments, one or more of the most important steps of the method may be performed by such a device.

[0229] In some exemplary embodiments, a programmable logic device such as a field programmable gate array can be used to perform some or all of the functions of the methods described herein. In some exemplary embodiments, the field programmable gate array can be operated with a microprocessor to perform one of the methods described herein. Typically, the method is preferably performed by a specific hardware device.

[0230] The description of the present invention is merely exemplary in nature, and therefore variant forms that do not deviate from the essence of the present invention are intended to be within the scope of the present invention. Such variant forms should not be considered as departing from the spirit and scope of the present invention. Therefore, it will be understood by those of ordinary skill in the art that various changes in form and details may be made without departing from the spirit and scope defined by the appended claims.

Claims

1. A method of a first communication node, include: Mapping modulation symbols and reference signals to resource regions; obtaining information about a phase shift for each subcarrier within a resource region; performing a first pre-compensation operation of phase by applying a phase shift to each subcarrier; as well as A signal to which the first pre-compensation operation is applied is sent to the second communication node.

2. The method according to claim 1, in, Obtaining information about the phase shift includes predicting the phase shift based on a position of a reference subcarrier, a phase shift difference between the reference subcarrier and another subcarrier, and a timing offset.

3. The method according to claim 2, in, The timing offset is a difference between a synchronization reference time and a predicted reception time of a received signal at the second communication node, and the timing offset is determined based on a distance between the first communication node and the second communication node.

4. The method according to claim 1, in, Obtaining information about the phase shift includes receiving, from the second communication node, information about the phase shift predicted based on a position of a reference subcarrier, a phase shift difference between the reference subcarrier and another subcarrier, and a timing offset.

5. The method according to claim 1, further comprising: include: performing an inverse fast Fourier transform (IFFT) operation on a result of the first pre-compensation operation; obtaining information of a cyclic shift for a second precompensation operation in time; as well as performing a second pre-compensation operation in time by applying a cyclic shift to a result of the IFFT operation; The signal sent to the second communication node is a signal to which the first pre-compensation operation and the second pre-compensation operation are applied.

6. The method according to claim 5, in, Obtaining information of the cyclic shift includes determining the cyclic shift based on a timing offset caused by movement of the second communication node and an IFFT size of an IFFT operation.

7. The method according to claim 5, in, Acquiring the information of the cyclic shift includes receiving, from the second communication node, information about the cyclic shift determined based on a timing offset caused by movement of the second communication node and an IFFT size of an IFFT operation.

8. The method according to claim 1, further comprising: include: sending information to the second communication node indicating that the first communication node supports the first precompensation operation; as well as Information is received from the second communication node indicating disabling of a post-compensation operation of the second communication node.

9. The method according to claim 1, in, The transmission of the signal is a repeated physical uplink shared channel (PUSCH) transmission, and power consistency and phase continuity are maintained by performing a first pre-compensation operation within a time domain window (TDW) in which the repeated PUSCH transmission is performed.

10. The method according to claim 1, in, The first communication node is a terminal in a non-terrestrial network, and the second communication node is a satellite or a base station in the non-terrestrial network.

11. A first communication node comprising at least one processor, in, The at least one processor causes the first communication node to execute: Mapping modulation symbols and reference signals to resource regions; obtaining information about a phase shift for each subcarrier within a resource region; performing a first pre-compensation operation of phase by applying a phase shift to each subcarrier; as well as A signal to which the first pre-compensation operation is applied is sent to the second communication node.

12. The first communication node according to claim 11, in, Upon obtaining the information about the phase shift, the at least one processor further causes the first communication node to perform: predicting the phase shift based on a position of a reference subcarrier, a phase shift difference between the reference subcarrier and another subcarrier, and a timing offset.

13. The first communication node according to claim 12, in, The timing offset is a difference between a synchronization reference time and a predicted reception time of a received signal at the second communication node, and the timing offset is determined based on a distance between the first communication node and the second communication node.

14. The first communication node according to claim 11, in, When obtaining information about the phase shift, the at least one processor further causes the first communication node to perform: receiving information about the phase shift predicted based on the position of the reference subcarrier, the phase shift difference between the reference subcarrier and another subcarrier, and the timing offset from the second communication node.

15. The first communication node according to claim 11, in, The at least one processor further causes the first communication node to execute: performing an inverse fast Fourier transform (IFFT) operation on a result of the first pre-compensation operation; obtaining information of a cyclic shift for a second precompensation operation in time; as well as performing a second pre-compensation operation in time by applying a cyclic shift to a result of the IFFT operation; The signal sent to the second communication node is a signal to which the first pre-compensation operation and the second pre-compensation operation are applied.

16. The first communication node according to claim 15, in, Upon obtaining the information of the cyclic shift, the at least one processor further causes the first communication node to perform: determining the cyclic shift based on a timing offset caused by movement of the second communication node and an IFFT size of the IFFT operation.

17. The first communication node according to claim 15, in, When obtaining the information of the cyclic shift, the at least one processor further causes the first communication node to perform: receiving, from the second communication node, information about the cyclic shift determined based on a timing offset caused by movement of the second communication node and an IFFT size of an IFFT operation.

18. The first communication node according to claim 11, in, The at least one processor further causes the first communication node to execute: sending information to the second communication node indicating that the first communication node supports the first precompensation operation; and Information is received from the second communication node indicating disabling of a post-compensation operation of the second communication node.

19. The first communication node according to claim 11, in, The transmission of the signal is a repeated physical uplink shared channel (PUSCH) transmission, and power consistency and phase continuity are maintained by performing a first pre-compensation operation within a time domain window (TDW) in which the repeated PUSCH transmission is performed.

20. The first communication node according to claim 11, in, The first communication node is a terminal in a non-terrestrial network, and the second communication node is a satellite or a base station in the non-terrestrial network.

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