KR20220152899A - Method and apparatus for determining and applying timing advance in communications system - Google Patents

Abstract

The present disclosure relates to a communication technique for converging a 5G communication system with IoT technology to support a higher data transfer rate than a 4G system, and a system thereof. The present disclosure can be applied to intelligent services (for example, smart home, smart building, smart city, smart car or connected car, health care, digital education, retail, security- and safety-related services, etc.) based on 5G communication technology and IoT-related technology. Disclosed in the present invention are a method and apparatus for a terminal to perform satellite communication. A method for processing a control signal of a terminal in a wireless communication system comprises the steps of: receiving a first control signal transmitted from a base station; processing the received first control signal; and transmitting a second control signal generated based on the processing, to the base station.

Description

Method and apparatus for determining and applying timing advance in communication system

The present invention relates to a communication system, and in particular, when a terminal transmits/receives a signal to and from a base station through a satellite, time offset correction may be required due to a long distance between the terminal and a satellite. Accordingly, in the present invention, the base station instructs the terminal with time offset information, the terminal calculates and applies a portion of the timing advance, the terminal reports the timing advance information to the base station, and the terminal calculates the time offset using the indicated information. A correction method and apparatus are provided.

Efforts are being made to develop an improved 5G communication system or pre-5G communication system to meet the growing demand for wireless data traffic after the commercialization of the 4G communication system. For this reason, the 5G communication system or pre-5G communication system is being called a Beyond 4G Network communication system or a Post LTE system. In order to achieve a high data rate, the 5G communication system is being considered for implementation in a mmWave band (eg, a 60 gigabyte (60 GHz) band). In order to mitigate the path loss of radio waves and increase the propagation distance of radio waves in the ultra-high frequency band, beamforming, massive MIMO, and Full Dimensional MIMO (FD-MIMO) are used in 5G communication systems. ), array antenna, analog beam-forming, and large scale antenna technologies are being discussed. In addition, to improve the network of the system, in the 5G communication system, an evolved small cell, an advanced small cell, a cloud radio access network (cloud RAN), and an ultra-dense network , Device to Device communication (D2D), wireless backhaul, moving network, cooperative communication, Coordinated Multi-Points (CoMP), and interference cancellation etc. are being developed. In addition, in the 5G system, advanced coding modulation (Advanced Coding Modulation: ACM) methods FQAM (Hybrid FSK and QAM Modulation) and SWSC (Sliding Window Superposition Coding), advanced access technologies FBMC (Filter Bank Multi Carrier), NOMA (non orthogonal multiple access) and SCMA (sparse code multiple access) are being developed.

On the other hand, the Internet is evolving from a human-centered connection network in which humans create and consume information to an Internet of Things (IoT) network in which information is exchanged and processed between distributed components such as things. IoE (Internet of Everything) technology, which combines IoT technology with big data processing technology through connection with a cloud server, etc., is also emerging. In order to implement IoT, technical elements such as sensing technology, wired/wireless communication and network infrastructure, service interface technology, and security technology are required, and recently, sensor networks for connection between objects and machine to machine , M2M), and MTC (Machine Type Communication) technologies are being studied. In the IoT environment, intelligent IT (Internet Technology) services that create new values in human life by collecting and analyzing data generated from connected objects can be provided. IoT is a field of smart home, smart building, smart city, smart car or connected car, smart grid, health care, smart home appliances, advanced medical service, etc. can be applied to

Accordingly, various attempts are being made to apply the 5G communication system to the IoT network. For example, technologies such as sensor network, machine to machine (M2M), and machine type communication (MTC) are implemented by techniques such as beamforming, MIMO, and array antenna, and 5G communication technologies There is. The application of the cloud radio access network (cloud RAN) as the big data processing technology described above can be said to be an example of convergence of 5G technology and IoT technology.

Meanwhile, as the cost of launching satellites drastically decreased in the late 2010s and into the 2020s, the number of companies trying to provide communication services through satellites increased. Accordingly, the satellite network has emerged as a next-generation network system that complements the existing terrestrial network. Although it does not provide a user experience comparable to that of a terrestrial network, it has the advantage of being able to provide communication services in areas where it is difficult to establish a terrestrial network or in a disaster situation. In addition, several companies and 3GPP standard organizations are promoting direct communication between smartphones and satellites.

When a terminal wants to connect to a base station through a satellite, a large delay time occurs for radio waves to arrive due to a long distance of hundreds of km, thousands of km, or more between the terminal and the satellite and between the satellite and the base station on the ground. This large delay time is much greater than a situation in which a terminal and a base station communicate directly in a terrestrial network. In addition, this delay time changes with time because the satellite continuously moves. All terminals change the delay time with satellites or base stations.

The present invention relates to a communication system, and in particular, when a terminal transmits and receives a signal to and from a base station through a satellite, the base station sets a time offset to compensate for a time-varying delay caused by a long distance to the satellite and movement of the satellite. A method and apparatus for instructing and correcting the terminal based thereon are provided. In addition, a terminal can calculate a part of a time offset based on satellite and its own location and time information, apply it, and provide a method and apparatus for reporting to a base station.

The present invention for solving the above problems is a method for processing a control signal of a terminal in a wireless communication system, comprising: receiving a first control signal transmitted from a base station; processing the received first control signal; and transmitting a second control signal generated based on the processing to the base station.

As described above, using the present invention, a terminal can access a base station through a satellite, the base station instructs a time offset to the terminal, and the terminal calculates and corrects the time offset to effectively exchange signals between the base station and the terminal. It is possible.

를 정하는 과정의 일례를 도시한 도면이다.
도27d는 본 발명에서 제공하는 방법으로, 초기접속에서부터 단말이

,

및

를 정하는 과정의 일례를 도시한 도면이다.
도 28은 본 개시의 일 실시예에 따른 단말의 초기 접속 절차의 일례를 도시한 도면이다.
도 29는 본 개시의 일 실시예에 따른 단말의 초기 접속 절차의 또다른 일례를 도시한 도면이다.
도 30a는 단말의 TA 값 보고를 위한 기지국 동작의 일례를 도시한 도면이다.
도 30b는 단말의 TA 값 보고를 위한 단말 동작의 일례를 도시한 도면이다.
도 31은 지상망과 위성망에서의 전파지연시간의 차이의 일례를 도시한 도면이다.
도 32는 본 발명의 실시예에 따른 단말의 내부 구조를 도시하는 블록도이다.
도 33은 본 발명의 실시예에 따른 위성의 내부 구조를 도시하는 블록도이다.
도 34는 본 발명의 실시예에 따른 기지국의 내부 구조를 도시하는 블록도이다.1 is a diagram showing the basic structure of a time-frequency domain, which is a radio resource domain in which the data or control channel is transmitted in downlink or uplink in an NR system.
2 is a diagram illustrating a control region in which a downlink control channel is transmitted in a 5G wireless communication system.
3 is a diagram showing an example in which eMBB, URLLC, and mMTC data are allocated to the entire system frequency band.
4A is a diagram illustrating an example in which eMBB, URLLC, and mMTC data are allocated by dividing system frequency bands.
4B is a diagram schematically illustrating an example of a message transmitted from a MAC layer to a physical layer in downlink in a communication system according to various embodiments of the present disclosure.
4C is a diagram schematically illustrating an example of a message transmitted from a MAC layer to a physical layer in an uplink in a communication system according to various embodiments of the present disclosure.
5 is a diagram illustrating an example of a process in which one transport block is divided into several code blocks and a CRC is added.
6 is a diagram showing how a synchronization signal (SS) and a physical broadcast channel (PBCH) of an NR system are mapped in the frequency and time domains.
7 is a diagram illustrating symbols in which SS/PBCH blocks can be transmitted according to subcarrier intervals.
8 is a diagram illustrating a processing time of a UE according to a timing advance when a UE receives a first signal and transmits a second signal for the UE in a 5G or NR system according to an embodiment disclosed herein.
9 is a diagram illustrating an example of scheduling and transmitting data (eg, TB) according to slots, receiving HARQ-ACK feedback for the corresponding data, and performing retransmission according to the feedback.
10 is a diagram showing an example of a communication system using satellites.
11 is a diagram illustrating the earth orbit period of a communication satellite according to the altitude or height of the satellite.
12 is a diagram showing a conceptual diagram of satellite-terminal direct communication.
13 is a diagram illustrating a utilization scenario of satellite-terminal direct communication.
FIG. 14 is a diagram illustrating an example of calculating an expected data throughput in uplink when a LEO satellite at an altitude of 1200 km and a terminal on the ground perform direct communication.
FIG. 15 is a diagram showing an example of calculating expected data throughput in uplink when a GEO satellite at an altitude of 35,786 km and a terminal on the ground perform direct communication.
16 is a diagram illustrating path loss values according to a path loss model between a terminal and a satellite, and path loss according to a path loss model between a terminal and a terrestrial communication base station.
FIG. 17 is a diagram showing formulas and results for calculating the amount of Doppler shift experienced by a signal transmitted from a satellite according to the altitude and location of a satellite and the location of a terminal user on the ground when a signal transmitted from a satellite is received by a ground user.
18 is a diagram showing the velocity of a satellite calculated from the altitude of the satellite.
19 is a diagram illustrating a Doppler shift experienced by different terminals in one beam transmitted from a satellite to the ground.
20 is a diagram illustrating a difference in Doppler shift occurring within one beam according to a position of a satellite determined from an elevation angle.
21 is a diagram illustrating a delay time from a terminal to a satellite and a round-trip delay time between a terminal and a satellite-base station according to a position of a satellite determined according to an altitude angle.
22 is a diagram illustrating a maximum difference value of a round-trip delay time depending on a user's position within one beam.
23 is a diagram showing an example of the RAR information structure.
24 is a diagram illustrating an example of a relationship between PRACH preamble configuration resources and RAR reception time in an LTE system.
25 is a diagram showing an example of the relationship between PRACH preamble configuration resources and RAR reception time in a 5G NR system.
26 is a diagram showing an example of downlink frame and uplink frame timing in a terminal.
FIG. 27A is a diagram illustrating an example of continuous motion of a satellite on the ground of the earth or in a terminal located on the earth as the satellite revolves around the earth along a satellite orbit.
27B is a diagram showing an example of the structure of an artificial satellite.
27c shows that the terminal from the initial access

It is a diagram showing an example of the process of determining.
27d is a method provided by the present invention, in which a terminal from initial access

,

and

It is a diagram showing an example of the process of determining.
28 is a diagram illustrating an example of an initial access procedure of a terminal according to an embodiment of the present disclosure.
29 is a diagram illustrating another example of an initial access procedure of a terminal according to an embodiment of the present disclosure.
30A is a diagram illustrating an example of an operation of a base station for reporting a TA value of a terminal.
30B is a diagram illustrating an example of a UE operation for reporting a TA value of the UE.
31 is a diagram showing an example of a difference in propagation delay time between a terrestrial network and a satellite network.
32 is a block diagram showing the internal structure of a terminal according to an embodiment of the present invention.
33 is a block diagram showing the internal structure of a satellite according to an embodiment of the present invention.
34 is a block diagram showing the internal structure of a base station according to an embodiment of the present invention.

In the new 5G communication, NR (New Radio access technology), it is being designed so that various services can be freely multiplexed in time and frequency resources, and accordingly, waveform/numerology and reference signals are dynamically or can be freely allocated. Optimized data transmission through measurement of channel quality and interference is important in order to provide optimal service to terminals in wireless communication, and accordingly, accurate measurement of channel conditions is essential. However, unlike 4G communication in which channel and interference characteristics do not change significantly depending on frequency resources, in the case of 5G channels, channel and interference characteristics vary greatly depending on the service. requires support of a subset of Meanwhile, in the NR system, types of supported services may be divided into categories such as enhanced mobile broadband (eMBB), massive machine type communications (mMTC), and ultra-reliable and low-latency communications (URLC). eMBB is a high-speed transmission of high-capacity data, mMTC is a service aimed at minimizing terminal power and accessing multiple terminals, and URLLC is a service that aims for high reliability and low latency. Different requirements may be applied according to the type of service applied to the terminal.

In this way, a plurality of services can be provided to users in a communication system, and in order to provide such a plurality of services to users, a method capable of providing each service within the same time period according to characteristics and a device using the same are required. .

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In describing the embodiments, descriptions of technical contents that are well known in the technical field to which the present invention pertains and are not directly related to the present invention will be omitted. This is to more clearly convey the gist of the present invention without obscuring it by omitting unnecessary description.

For the same reason, in the accompanying drawings, some components are exaggerated, omitted, or schematically illustrated. Also, the size of each component does not entirely reflect the actual size. In each figure, the same reference number is assigned to the same or corresponding component.

Advantages and features of the present invention, and methods for achieving them, will become clear with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and only the present embodiments make the disclosure of the present invention complete, and common knowledge in the art to which the present invention belongs It is provided to fully inform the holder of the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numbers designate like elements throughout the specification.

At this time, it will be understood that each block of the process flow chart diagrams and combinations of the flow chart diagrams can be performed by computer program instructions. These computer program instructions may be embodied in a processor of a general purpose computer, special purpose computer, or other programmable data processing equipment, so that the instructions executed by the processor of the computer or other programmable data processing equipment are described in the flowchart block(s). It creates means to perform functions. These computer program instructions may also be stored in a computer usable or computer readable memory that can be directed to a computer or other programmable data processing equipment to implement functionality in a particular way, such that the computer usable or computer readable memory The instructions stored in are also capable of producing an article of manufacture containing instruction means that perform the functions described in the flowchart block(s). The computer program instructions can also be loaded on a computer or other programmable data processing equipment, so that a series of operational steps are performed on the computer or other programmable data processing equipment to create a computer-executed process to generate computer or other programmable data processing equipment. Instructions for performing processing equipment may also provide steps for performing the functions described in the flowchart block(s).

Additionally, each block may represent a module, segment, or portion of code that includes one or more executable instructions for executing specified logical function(s). It should also be noted that in some alternative implementations it is possible for the functions mentioned in the blocks to occur out of order. For example, two blocks shown in succession may in fact be executed substantially concurrently, or the blocks may sometimes be executed in reverse order depending on their function.

At this time, the term '~unit' used in this embodiment means software or a hardware component such as FPGA or ASIC, and '~unit' performs certain roles. However, '~ part' is not limited to software or hardware. '~bu' may be configured to be in an addressable storage medium and may be configured to reproduce one or more processors. Therefore, as an example, '~unit' refers to components such as software components, object-oriented software components, class components, and task components, processes, functions, properties, and procedures. , subroutines, segments of program code, drivers, firmware, microcode, circuitry, data, databases, data structures, tables, arrays, and variables. Functions provided within components and '~units' may be combined into smaller numbers of components and '~units' or further separated into additional components and '~units'. In addition, components and '~units' may be implemented to play one or more CPUs in a device or a secure multimedia card. Also, in an embodiment, '~ unit' may include one or more processors.

The wireless communication system has moved away from providing voice-oriented services in the early days and, for example, 3GPP's HSPA (high speed packet access), LTE (long term evolution or E-UTRA (evolved universal terrestrial radio access)), LTE-Advanced (LTE-A), HRPD (high rate packet data) of 3GPP2, UMB (ultra mobile broadband), and IEEE's 802.16e, etc. are doing In addition, as a 5G wireless communication system, a communication standard of 5G or NR (new radio) is being created.

As a representative example of the broadband wireless communication system, an orthogonal frequency division multiplexing (OFDM) method is employed in downlink (DL) and uplink in the NR system. However, more specifically, a cyclic-prefix OFDM (CP-OFDM) scheme is employed in downlink, and two discrete Fourier transform spreading OFDM (DFT-S-OFDM) schemes are employed in uplink along with CP-OFDM. Uplink refers to a radio link in which a user equipment (UE) or MS (mobile station) transmits data or control signals to a base station (gNode B or base station (BS)), and downlink refers to a radio link in which a base station transmits a terminal A radio link that transmits data or control signals. The above multiple access scheme distinguishes data or control information of each user by allocating and operating time-frequency resources to carry data or control information for each user so that they do not overlap each other, that is, so that orthogonality is established. do.

The NR system adopts a hybrid automatic repeat request (HARQ) method for retransmitting corresponding data in the physical layer when decoding failure occurs in initial transmission. The HARQ scheme enables the transmitter to retransmit the corresponding data in the physical layer by sending negative acknowledgment (NACK) to the transmitter when the receiver fails to accurately decode (decode) the data. The receiver improves data reception performance by combining data retransmitted by the transmitter with previously failed data to be decoded. In addition, when the receiver accurately decodes the data, it may transmit information (acknowledgement: ACK) indicating success of decoding to the transmitter so that the transmitter can transmit new data.

1 is a diagram showing the basic structure of a time-frequency domain, which is a radio resource domain in which the data or control channel is transmitted in downlink or uplink in an NR system.

)=14). 1 서브프레임은 하나 또는 복수 개의 슬롯으로 구성될 수 있으며, 1 서브프레임당 슬롯의 개수는 부반송파 간격에 대한 설정 값 μ에 따라 다를 수 있다. 도 2의 일 예에서는 부반송파 간격 설정 값으로 μ=0인 경우와 μ=1인 경우가 도시되어 있다. μ=0일 경우, 1 서브프레임은 1개의 슬롯으로 구성될 수 있고, μ=1일 경우, 1 서브프레임은 2개의 슬롯으로 구성될 수 있다. 즉 부반송파 간격에 대한 설정 값 μ에 따라 1 서브프레임 당 슬롯 수(

)가 달라질 수 있고, 이에 따라 1 프레임 당 슬롯 수(

)가 달라질 수 있다. 각 부반송파 간격 설정 μ에 따른

및

는 하기의 표 1로 정의될 수 있다.In FIG. 1, the horizontal axis represents the time domain and the vertical axis represents the frequency domain. The minimum transmission unit in the time domain is an OFDM symbol, and N _symb (102) OFDM symbols are gathered to form one slot (106). The length of the subframe is defined as 1.0 ms, and the radio frame 114 is defined as 10 ms. The minimum transmission unit in the frequency domain is a subcarrier, and the bandwidth of the entire system transmission bandwidth consists of a total of N _BW (104) subcarriers. One frame may be defined as 10 ms. One subframe may be defined as 1 ms, and thus one frame may consist of a total of 10 subframes. 1 slot may be defined as 14 OFDM symbols (that is, the number of symbols per slot (

)=14). One subframe may consist of one or a plurality of slots, and the number of slots per subframe may vary according to a set value μ for the subcarrier interval. In an example of FIG. 2 , a case where μ=0 and a case where μ=1 are shown as subcarrier interval setting values. When μ=0, 1 subframe may consist of 1 slot, and when μ=1, 1 subframe may consist of 2 slots. That is, the number of slots per 1 subframe according to the setting value μ for the subcarrier interval (

) may vary, and accordingly, the number of slots per frame (

) may vary. According to each subcarrier spacing setting μ

and

Can be defined in Table 1 below.

0 14 10 One One 14 20 2 2 14 40 4 3 14 80- 8 4 14 160 16

A terminal before radio resource control (RRC) connection may receive an initial bandwidth part (initial BWP) for initial access from a base station through a master information block (MIB). More specifically, the UE receives system information (remaining system information; RMSI or system information block 1; may correspond to SIB1) necessary for initial access through the MIB in the initial access step. Physical downlink control channel (PDCCH) ) can receive control resource set (CORESET) and setting information about a search space (search space) that can be transmitted. The control area and search space set by MIB can be regarded as identity (ID) 0, respectively. The base station may notify the terminal of setting information such as frequency allocation information, time allocation information, and numerology for the control region #0 through the MIB. In addition, the base station may notify the terminal of configuration information about the monitoring period and occasion for control region #0, that is, configuration information about search space #0, through the MIB. The terminal may regard the frequency domain set as the control domain #0 acquired from the MIB as an initial bandwidth part for initial access. At this time, the identifier (ID) of the initial bandwidth part may be regarded as 0.

MIB may include the following information.

-- ASN1START

--TAG-MIB-START

MIB ::= SEQUENCE {

systemFrameNumber BIT STRING(SIZE(6)),

subCarrierSpacingCommon ENUMERATED {scs15or60, scs30or120},

ssb-SubcarrierOffset INTEGER (0..15),

dmrs-TypeA-Position ENUMERATED {pos2, pos3},

pdcch-ConfigSIB1 PDCCH-ConfigSIB1,

cellBarred ENUMERATED {barred, notBarred},

intraFreqReselection ENUMERATED {allowed, notAllowed},

spare BIT STRING (SIZE (1))

}

--TAG-MIB-STOP

-- ASN1STOP

MIB field descriptions

-cellBarred

Value barred means that the cell is barred, as defined in TS 38.304 [20].

-dmrs-TypeA-Position

Position of (first) DM-RS for downlink (see TS 38.211 [16], clause 7.4.1.1.2) and uplink (see TS 38.211 [16], clause 6.4.1.1.3).

- intraFreqReselection

Controls cell selection/reselection to intra-frequency cells when the highest ranked cell is barred, or treated as barred by the UE, as specified in TS 38.304 [20].

-pdcch-ConfigSIB1

Determines a common ControlResourceSet (CORESET), a common search space and necessary PDCCH parameters. If the field ssb-SubcarrierOffset indicates that SIB1 is absent, the field pdcch-ConfigSIB1 indicates the frequency positions where the UE may find SS/PBCH block with SIB1 or the frequency range where the network does not provide SS/PBCH block with SIB1 (see TS 38.213 [13], clause 13).

-ssb-SubcarrierOffset

Corresponds to kSSB (see TS 38.213 [13]), which is the frequency domain offset between SSB and the overall resource block grid in number of subcarriers. (See TS 38.211 [16], clause 7.4.3.1).

The value range of this field may be extended by an additional most significant bit encoded within PBCH as specified in TS 38.213 [13].

This field may indicate that this cell does not provide SIB1 and that there is hence no CORESET#0 configured in MIB (see TS 38.213 [13], clause 13). In this case, the field pdcch-ConfigSIB1 may indicate the frequency positions where the UE may (not) find a SS/PBCH with a control resource set and search space for SIB1 (see TS 38.213 [13], clause 13).

-subCarrierSpacingCommon

Subcarrier spacing for SIB1, Msg.2/4 for initial access, paging and broadcast SI-messages. If the UE acquires this MIB on an FR1 carrier frequency, the value scs15or60 corresponds to 15 kHz and the value scs30or120 corresponds to 30 kHz. If the UE acquires this MIB on an FR2 carrier frequency, the value scs15or60 corresponds to 60 kHz and the value scs30or120 corresponds to 120 kHz.

-systemFrameNumber

The 6 most significant bits (MSB) of the 10-bit System Frame Number (SFN). The 4 LSB of the SFN are conveyed in the PBCH transport block as part of channel coding (i.e. outside the MIB encoding), as defined in clause 7.1 in TS 38.212 [17].

In the method of setting the bandwidth part, terminals before RRC connection (connected) may receive setting information on the initial bandwidth part through the MIB in the initial access step. More specifically, the terminal can receive a control region for a downlink control channel in which downlink control information (DCI) for scheduling the SIB can be transmitted from the MIB of a physical broadcast channel (PBCH). At this time, the bandwidth of the control region set as the MIB may be regarded as an initial bandwidth portion, and the terminal may receive a physical downlink shared channel (PDSCH) through which the SIB is transmitted through the set initial bandwidth portion. The initial bandwidth portion may be used for other system information (OSI), paging, and random access in addition to the purpose of receiving the SIB.

When one or more bandwidth parts are configured for the UE, the base station may instruct the UE to change the bandwidth part using a bandwidth part indicator field in the DCI.

A basic unit of resources in the time-frequency domain is a resource element (RE), which can be represented by an OFDM symbol index and a subcarrier index. A resource block 108 (resource block; RB or physical resource block; PRB) is defined as N _RBs 110 contiguous subcarriers in the frequency domain. In general, the minimum transmission unit of data is the RB unit. In the NR system, N _symb = 14 and N _RB = 12, and N _BW is proportional to the bandwidth of the system transmission band. The data rate may increase in proportion to the number of RBs scheduled for the UE.

In the NR system, in the case of an FDD system in which downlink and uplink are separately operated by frequency, a downlink transmission bandwidth and an uplink transmission bandwidth may be different from each other. The channel bandwidth represents the RF bandwidth corresponding to the system transmission bandwidth. Tables 2 and 3 show some of the correspondence between system transmission bandwidth, subcarrier spacing and channel bandwidth defined in NR systems in frequency bands lower than 6 GHz and higher than 6 GHz, respectively. indicate For example, in a NR system having a channel bandwidth of 100 MHz with a subcarrier width of 30 kHz, the transmission bandwidth consists of 273 RBs. In the following, N/A may be a bandwidth-subcarrier combination not supported by the NR system.

[Table 2]: Configuration of FR1 (Frequency Range 1)

[Table 3]: Configuration of FR2 (Frequency Range 2)

In the NR system, the frequency range may be divided into FR1 and FR2 and defined as shown in Table 4 below.

[Table 4]

In the above, the ranges of FR1 and FR2 may be changed and applied differently. For example, the frequency range of FR1 may be changed and applied from 450 MHz to 6000 MHz.

Next, a synchronization signal (SS)/PBCH block in 5G will be described.

The SS/PBCH block may mean a physical layer channel block composed of a primary SS (PSS), a secondary SS (SSS), and a PBCH. Specifically, it is as follows.

- PSS: This is a signal that is a standard for downlink time/frequency synchronization and provides some information of cell ID.

- SSS: serves as a standard for downlink time/frequency synchronization, and provides remaining cell ID information not provided by PSS. Additionally, it can serve as a reference signal for demodulation of PBCH.

- PBCH: Provides essential system information necessary for transmitting and receiving the data channel and control channel of the terminal. Essential system information may include search space-related control information indicating radio resource mapping information of a control channel, scheduling control information for a separate data channel through which system information is transmitted, and the like.

- SS/PBCH block: The SS/PBCH block consists of a combination of PSS, SSS, and PBCH. One or a plurality of SS/PBCH blocks may be transmitted within 5 ms, and each SS/PBCH block to be transmitted may be distinguished by an index.

The UE can detect the PSS and SSS in the initial access stage and decode the PBCH. The terminal can obtain the MIB from the PBCH and can receive control region #0 (which may correspond to a control region having a control region index of 0) set therefrom. The UE may perform monitoring for control region #0 assuming that the selected SS/PBCH block and a demodulation reference signal (DMRS) transmitted in control region #0 are quasi co location (QCL). The terminal may receive system information through downlink control information transmitted in control region #0. The terminal may obtain random access channel (RACH)-related configuration information required for initial access from the received system information. The terminal may transmit a physical RACH (PRACH) to the base station in consideration of the selected SS/PBCH index, and the base station receiving the PRACH may acquire information about the SS/PBCH block index selected by the terminal. Through this process, the base station can know that the terminal has selected a certain block from among each SS/PBCH block and monitors the control region #0 associated therewith.

Next, downlink control information (DCI) in the 5G system will be described in detail.

In the 5G system, scheduling information for uplink data (or physical uplink shared channel (PUSCH)) or downlink data (or physical downlink shared channel (PDSCH)) is provided through DCI It is transmitted from the base station to the terminal. The UE may monitor the DCI format for fallback and the DCI format for non-fallback with respect to PUSCH or PDSCH. The contingency DCI format may be composed of a fixed field predefined between the base station and the terminal, and the non-preparation DCI format may include a configurable field. In addition to this, there are various formats of DCI, and each format can indicate whether it is a DCI for power control or a DCI for notifying a slot format indicator (SFI).

DCI may be transmitted through PDCCH, which is a physical downlink control channel, through channel coding and modulation processes. A cyclic redundancy check (CRC) is attached to the DCI message payload, and the CRC may be scrambled with a radio network temporary identifier (RNTI) corresponding to the identity of the terminal. Different RNTIs may be used according to the purpose of the DCI message, eg, UE-specific data transmission, power control command, or random access response. That is, the RNTI is not transmitted explicitly but is included in the CRC calculation process and transmitted. Upon receiving the DCI message transmitted on the PDCCH, the UE checks the CRC using the allocated RNTI, and if the CRC check result is correct, the UE can know that the corresponding message has been transmitted to the UE. The PDCCH is transmitted after being mapped in a control resource set (CORESET) set to the terminal.

For example, DCI scheduling a PDSCH for system information (SI) may be scrambled with SI-RNTI. A DCI for scheduling a PDSCH for a random access response (RAR) message may be scrambled with RA-RNTI. DCI scheduling PDSCH for paging messages may be scrambled with P-RNTI. DCI notifying SFI (slot format indicator) may be scrambled with SFI-RNTI. DCI notifying transmit power control (TPC) may be scrambled with TPC-RNTI. DCI scheduling UE-specific PDSCH or PUSCH may be scrambled with C-RNTI (Cell RNTI).

DCI format 0_0 can be used as a fallback DCI for scheduling PUSCH, and in this case, CRC can be scrambled with C-RNTI. DCI format 0_0 in which CRC is scrambled with C-RNTI may include, for example, the following information.

[Table 5]

DCI format 0_1 can be used as a non-backup DCI for scheduling PUSCH, and in this case, CRC can be scrambled with C-RNTI. DCI format 0_1 in which CRC is scrambled with C-RNTI may include, for example, the following information.

[Table 6]

DCI format 1_0 can be used as a fallback DCI for scheduling PDSCH, and in this case, CRC can be scrambled with C-RNTI. DCI format 1_0 in which CRC is scrambled with C-RNTI may include, for example, the following information.

[Table 7]

DCI format 1_1 can be used as a non-backup DCI for scheduling PDSCH, and in this case, CRC can be scrambled with C-RNTI. DCI format 1_1 in which CRC is scrambled with C-RNTI may include, for example, the following information.

[Table 8]

Hereinafter, a method of allocating time domain resources for a data channel in a 5G communication system will be described.

The base station may set a table for time domain resource allocation information for the downlink data channel (PDSCH) and uplink data channel (PUSCH) to the terminal through higher layer signaling (eg, RRC signaling). For PDSCH, a table consisting of maxNrofDL-Allocations=16 entries can be set, and for PUSCH, a table consisting of maxNrofUL-Allocations=16 entries can be set. The time domain resource allocation information includes, for example, PDCCH-to-PDSCH slot timing (corresponding to a time interval in units of slots between the time of receiving the PDCCH and the time of transmitting the PDSCH scheduled by the received PDCCH, denoted as K0), or PDCCH-to-PUSCH slot timing (corresponding to the time interval in units of slots between the time when the PDCCH is received and the time when the PUSCH scheduled by the received PDCCH is transmitted, denoted as K2), PDSCH or PUSCH scheduled within the slot Information on the location and length of the start symbol, mapping type of PDSCH or PUSCH, etc. may be included. For example, information such as Tables 9 and 10 below may be notified from the base station to the terminal.

PDSCH-TimeDomainResourceAllocationList information element
PDSCH-TimeDomainResourceAllocationList ::= SEQUENCE (SIZE(1..maxNrofDL-Allocations)) OF PDSCH-TimeDomainResourceAllocation

PDSCH-TimeDomainResourceAllocation ::= SEQUENCE {
k0 INTEGER(0..32) OPTIONAL, -- Need S
(PDCCH-to-PDSCH timing, per slot)
mappingType ENUMERATED {typeA, typeB},
(PDSCH mapping type)
startSymbolAndLength INTEGER (0..127)
(start symbol and length of PDSCH)
}

PUSCH-TimeDomainResourceAllocation information element
PUSCH-TimeDomainResourceAllocationList ::= SEQUENCE (SIZE(1..maxNrofUL-Allocations)) OF PUSCH-TimeDomainResourceAllocation

PUSCH-TimeDomainResourceAllocation ::= SEQUENCE {
k2 INTEGER(0..32) OPTIONAL, -- Need S
(PDCCH-to-PUSCH timing, per slot)
mappingType ENUMERATED {typeA, typeB},
(PUSCH mapping type)
startSymbolAndLength INTEGER (0..127)
(start symbol and length of PUSCH)
}

The base station may notify the terminal of one of the table entries for the time domain resource allocation information to the terminal through L1 signaling (eg, DCI) (eg, the 'time domain resource allocation' field in the DCI may be indicated). can). The terminal may obtain time domain resource allocation information for the PDSCH or PUSCH based on the DCI received from the base station.

In the following, a downlink control channel in a 5G communication system will be described in more detail with reference to the drawings.

2 is a diagram showing an example of a control region in which a downlink control channel is transmitted in a 5G wireless communication system. 2 shows a UE bandwidth part 210 on the frequency axis and two control regions (control region # 1 (201) and control region # 2 (202)) within 1 slot 220 on the time axis. Shows an example of what has been done. The control regions 201 and 202 may be set to a specific frequency resource 203 within the entire terminal bandwidth portion 210 on the frequency axis. The time axis may be set to one or a plurality of OFDM symbols, and this may be defined as a control region length (Control Resource Set Duration, 204). Referring to the illustrated example of FIG. 2 , control region #1 (201) is set to a control region length of 2 symbols, and control region #2 (202) is set to a control region length of 1 symbol.

The above-described control region in 5G may be set by the base station to the terminal through higher layer signaling (eg, system information, MIB, RRC signaling). Setting the control region to the terminal means providing information such as a control region identifier (Identity), a frequency location of the control region, and a symbol length of the control region. For example, the higher layer signaling may include information in Table 11 below.

ControlResourceSet ::= SEQUENCE {
-- Corresponds to L1 parameter 'CORESET-ID'

controlResourceSetId ControlResourceSetId,
(control area identifier (Identity))
frequencyDomainResources BIT STRING (SIZE (45)),
(frequency axis resource allocation information)
duration INTEGER (1..maxCoReSetDuration),
(time axis resource allocation information)
cce-REG-MappingType CHOICE {
(CCE-to-REG mapping method)
interleaved SEQUENCE {

reg-BundleSize ENUMERATED {n2, n3, n6},
(REG bundle size)

precoderGranularity ENUMERATED {sameAsREG-bundle, allContiguousRBs},

interleaverSize ENUMERATED {n2, n3, n6}
(interleaver size)

shiftIndex INTEGER(0..maxNrofPhysicalResourceBlocks-1) OPTIONAL
(Interleaver Shift)
},
nonInterleaved NULL
},
tci-StatesPDCCH SEQUENCE(SIZE (1..maxNrofTCI-StatesPDCCH)) OF TCI-StateId OPTIONAL,
(QCL setting information)
tci-PresentInDCI ENUMERATED {enabled} OPTIONAL, -- Need S
}

In Table 11, tci-StatesPDCCH (simply named TCI (transmission configuration indication) state) configuration information includes one or more SS/PBCH block indexes or CSI-RS ( channel state information reference signal) index information.

For example, each control information included in DCI format 1_1, which is scheduling control information (DL grant) for downlink data, may be as follows.

- Carrier indicator: indicates on which carrier the data scheduled by DCI is transmitted - 0 or 3 bits

- Identifier for DCI formats: Indicates a DCI format, and is an indicator that specifically distinguishes whether the corresponding DCI is for downlink or uplink. - [1] bits

- Bandwidth part indicator: Indicates when there is a change in the bandwidth part - 0, 1 or 2 bits

- Frequency domain resource assignment: This is resource allocation information indicating frequency domain resource allocation, and the expressed resource is different depending on whether the resource allocation type is 0 or 1.

- Time domain resource assignment: Resource allocation information indicating time domain resource allocation, which may indicate higher layer signaling or one setting of a predetermined PDSCH time domain resource allocation list -1, 2, 3, or 4 bits

- VRB-to-PRB mapping: Indicates the mapping relationship between virtual resource blocks (VRBs) and physical resource blocks (PRBs) - 0 or 1 bit

- PRB bundling size indicator: Indicates the physical resource block bundling size assuming that the same precoding is applied - 0 or 1 bit

- Rate matching indicator: Indicates which rate match group is applied among rate match groups set to higher layers applied to PDSCH - 0, 1, or 2 bits

- ZP CSI-RS trigger: trigger zero power channel state information reference signal - 0, 1, or 2 bits

- Transport block (TB) related configuration information: Indicates a modulation and coding scheme (MCS), new data indicator (NDI), and redundancy version (RV) for one or two TBs.

- Modulation and coding scheme (MCS): indicates the modulation scheme and coding rate used for data transmission. That is, a coding rate value capable of indicating TBS and channel coding information may be indicated along with information on whether it is QPSK, 16QAM, 64QAM, or 256QAM.

- New data indicator: indicates whether HARQ initial transmission or retransmission.

- Redundancy version: indicates the redundancy version of HARQ.

- HARQ process number: Indicates HARQ process number applied to PDSCH - 4 bits

- Downlink assignment index: This is an index for generating a dynamic HARQ-ACK codebook when reporting HARQ-ACK for PDSCH - 0 or 2 or 4 bits

- TPC command for scheduled PUCCH: Power control information applied to PUCCH for HARQ-ACK reporting on PDSCH - 2 bits

- PUCCH resource indicator: information indicating a resource of PUCCH for HARQ-ACK reporting on PDSCH - 3 bits

- PDSCH-to-HARQ_feedback timing indicator: Configuration information on which slot the PUCCH for reporting HARQ-ACK for PDSCH is transmitted in - 3 bits

- Antenna ports: Information indicating antenna ports of PDSCH DMRS and DMRS CDM groups to which PDSCH is not transmitted - 4, 5 or 6 bits

- Transmission configuration indication: Information indicating beam related information of PDSCH - 0 or 3 bits

- SRS request: information requesting SRS transmission - 2 bits

- CBG transmission information: information indicating which code block group (CBG) data is transmitted through PDSCH when code block group-based retransmission is configured - 0, 2, 4, 6, or 8 bits

- CBG flushing out information: information indicating whether the code block group previously received by the terminal can be used for HARQ combining - 0 or 1 bit

- DMRS sequence initialization: Indicates DMRS sequence initialization parameters - 1 bit

In the case of data transmission through PDSCH or PUSCH, time domain resource assignment is information about a slot in which PDSCH/PUSCH is transmitted, and a start symbol position S in the corresponding slot and a symbol to which PDSCH/PUSCH is mapped. It can be conveyed by the number L. In the above, S may be a relative position from the start of the slot, L may be the number of consecutive symbols, and S and L are defined as in Equation 1 below. can be determined

[Equation 1]

In the NR system, the terminal can receive information on the SLIV value, PDSCH/PUSCH mapping type, and slot through which PDSCH/PUSCH is transmitted in one row through RRC configuration (for example, the information is configured in the form of a table). can be). Then, in the time domain resource allocation of the DCI, the base station can transmit information about the SLIV value, the PDSCH/PUSCH mapping type, and the slot through which the PDSCH/PUSCH is transmitted to the terminal by indicating the index value in the set table.

In the NR system, PDSCH mapping types are defined as type A and type B. In PDSCH mapping type A, the first symbol of DMRS symbols is located in the second or third OFDM symbol of a slot. In the PDSCH mapping type B, the first symbol among the DMRS symbols of the first OFDM symbol in the time domain resource allocated for PUSCH transmission is located.

Downlink data can be transmitted on PDSCH, which is a physical channel for downlink data transmission. The PDSCH can be transmitted after the control channel transmission period, and scheduling information such as a specific mapping position in the frequency domain and a modulation method is determined based on the DCI transmitted through the PDCCH.

Among the control information constituting the DCI, the base station notifies the terminal of the modulation method applied to the PDSCH to be transmitted and the size of data to be transmitted (transport block size, TBS) through the MCS. In an embodiment, the MCS may consist of 5 bits or more or less bits. The TBS corresponds to a size before channel coding for error correction is applied to data (transport block, TB) to be transmitted by the base station.

In the present invention, a transport block (TB) may include a medium access control (MAC) header, a MAC control element, one or more MAC service data units (SDUs), and padding bits. Alternatively, TB may indicate a unit of data delivered from the MAC layer to a physical layer or a MAC protocol data unit (PDU).

Modulation methods supported by the NR system are QPSK (quadrature phase shift keying), 16QAM (quadrature amplitude modulation), 64QAM, and 256QAM, and each modulation order (Q _m ) corresponds to 2, 4, 6, and 8 do. That is, 2 bits per symbol can be transmitted in case of QPSK modulation, 4 bits per symbol in case of 16QAM modulation, 6 bits per symbol in case of 64QAM modulation, and 8 bits can be transmitted per symbol in case of 256QAM modulation.

3 and 4a are diagrams illustrating an example in which eMBB, URLLC, and mMTC data, which are services considered in a 5G or NR system, are allocated in frequency-time resources.

Referring to FIGS. 3 and 4A , it is possible to check how frequency and time resources are allocated for information transmission in each system.

3 is a diagram showing an example in which eMBB, URLLC, and mMTC data are allocated to the entire system frequency band. First, in FIG. 3, data for eMBB, URLLC, and mMTC are allocated in the entire system frequency band 300. If transmission is required because URLLC data (303, 305, 307) occurs while eMBB (301) and mMTC (309) are allocated and transmitted in a specific frequency band, the part where eMBB (301) and mMTC (309) are already allocated URLLC data (303, 305, 307) can be transmitted without emptying or not transmitting. Among the above services, since URLLC needs to reduce latency, URLLC data can be allocated (303, 305, 307) to a part of the resource 301 to which eMBB is allocated and transmitted. Of course, when URLLC is additionally allocated and transmitted in resources to which eMBB is allocated, eMBB data may not be transmitted in overlapping frequency-time resources, and thus transmission performance of eMBB data may be lowered. That is, in the above case, eMBB data transmission failure may occur due to URLLC allocation.

4A is a diagram illustrating an example in which eMBB, URLLC, and mMTC data are allocated by dividing system frequency bands. In FIG. 4A , the entire system frequency band 400 can be divided and used to transmit services and data in subbands 402 , 404 , and 406 . Information related to the subband configuration may be determined in advance, and this information may be transmitted from the base station to the terminal through higher level signaling. Alternatively, the subbands may be arbitrarily divided by the base station or the network node to provide services to the terminal without transmitting separate subband configuration information. In FIG. 4A , subband 402 is used for eMBB data transmission, subband 404 is used for URLLC data transmission, and subband 406 is used for mMTC data transmission.

The terms physical channel and signal in the NR system may be used to describe the method and apparatus proposed in the embodiment. However, the content of the present invention can be applied to a wireless communication system other than the NR system.

Hereinafter, embodiments of the present invention will be described in detail with accompanying drawings. In addition, in describing the present invention, if it is determined that a detailed description of a related function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted. In addition, terms to be described later are terms defined in consideration of functions in the present invention, which may vary according to the intention or custom of a user or operator. Therefore, the definition should be made based on the contents throughout this specification.

In the present invention, downlink (DL) is a radio transmission path of a signal transmitted from a base station to a terminal, and uplink (UL) refers to a radio transmission path of a signal transmitted from a terminal to a base station.

Although an embodiment of the present invention is described below using an NR system as an example, the embodiment of the present invention can be applied to other communication systems having a similar technical background or channel type. In addition, the embodiments of the present invention can be applied to other communication systems through some modification within a range that does not greatly deviate from the scope of the present invention as determined by a person with skillful technical knowledge.

In the present invention, the conventional terms of a physical channel and a signal may be used interchangeably with data or control signals. For example, PDSCH is a physical channel through which data is transmitted, but in the present invention, PDSCH may be referred to as data.

Hereinafter, upper signaling in the present invention is a method of transmitting a signal from a base station to a terminal using a downlink data channel of the physical layer or from a terminal to a base station using an uplink data channel of the physical layer, and RRC signaling or MAC control element. (MAC CE; MAC control element).

In various embodiments of the present disclosure, the TA is a MAC Control Element (CE), for example, a timing advance command MAC CE (Timing Advance Command MAC CE), or an absolute timing advance command MAC CE (Absolute Timing Advance Command MAC CE). can be transmitted via

Meanwhile, a message from the MAC layer delivered to the physical layer, eg, a MAC PDU, may include one or more MAC sub-PDUs. Each MAC sub-PDU may contain one of the following:

. MAC sub-header only (including padding)

. MAC subheader and MAC SDU

. MAC subheader and MAC CE

. MAC subheader and padding

MAC SDUs have a variable size, and each MAC subheader may correspond to a MAC SDU, MAC CE, or padding.

Meanwhile, a message from the MAC layer transmitted to the physical layer, for example, a MAC PDU, may be configured as shown in FIGS. 4B and 4C in the case of downlink and uplink, respectively.

First, referring to FIG. 4B , an example of a message transmitted from a MAC layer to a physical layer in a downlink in a communication system according to various embodiments of the present disclosure will be described.

4B is a diagram schematically illustrating an example of a message transmitted from a MAC layer to a physical layer in downlink in a communication system according to various embodiments of the present disclosure.

Referring to FIG. 4B, an example of a message transmitted from the MAC layer to the physical layer in the downlink may be a downlink MAC PDU (DL MAC PDU). 4b, a MAC sub-PDU including MAC CE 1 includes an R/LCID sub-header and a fixed-sized MAC CE (MAC CE), and a MAC sub-PDU including MAC CE 2 includes R/F/ LCID/L subheader and variable-sized MAC CE (variable-sized MAC CE). In addition, the MAC sub-PDU including the MAC SDU includes an R/F/LCID/L sub-header and a MAC SUD.

4B, LCID represents a logical channel ID (logical channel ID) field, and the LCID field indicates an instance of a corresponding MAC SDU or a type or padding of a corresponding MAC CE. Table B describes it in detail. Here, Table A shows LCID values for DL-SCH, and Table B shows LCID values for UL-SCH. There is one LCID field for each MAC sub-header, and the size of the LCID field is 6 bits. When the LCID field is set to "34", for example, one additional octet exists in the MAC sub-header including the eLCID field, and follows the octet including the LCID field. When the LCID field is set to "33", for example, two additional octets exist in the MAC sub-header including the eLCID field, and these two octets follow the octet including the LCID field.

In addition, eLCID indicates an extended logical channel ID field and indicates the type of a logical channel instance of a corresponding MAC SDU or a corresponding MAC CE. The size of the eLCID field is 8 bits or 16 bits.

In addition, L represents a length field, and the length field indicates the length of a corresponding MAC SDU or variable size MAC CE. There is one length field for each MAC sub-header excluding sub-headers corresponding to MAC SDUs including the fixed-size MAC CEs, padding, or UL common control channel (CCCH). The size of the length field is indicated by the F field.

In addition, F represents a format field and indicates the size of a length field. There is one F field for each MAC sub-header excluding MAC SDUs including fixed MAC CEs, padding, and UL CCCH. The size of the F field is 1 bit. For example, a value of 0 indicates 8 bits of the length field, and a value of 1 indicates 16 bits of the length field as another example.

Also, R is a reserved bit, and is set to “0” as an example.

As shown in FIG. 4B, MAC CEs, for example, MAC CE 1 and MAC CE 2 are co-located, and the MAC sub-PDU(s) containing the MAC CE(s) are the MAC sub-PDU(s) containing the MAC SDU. It is placed before the MAC sub-PDU including the PDU and padding. Here, the size of the padding may be zero.

Next, an example of a message transmitted from a MAC layer to a physical layer in an uplink in a communication system according to various embodiments of the present disclosure will be described with reference to FIG. 4C.

4C is a diagram schematically illustrating an example of a message transmitted from a MAC layer to a physical layer in an uplink in a communication system according to various embodiments of the present disclosure.

Referring to FIG. 4C, an example of a message transmitted from the MAC layer to the physical layer in uplink may be an uplink MAC PDU (UL MAC PDU). 4-b, a MAC sub-PDU including MAC CE 1 includes an R/LCID sub-header and a fixed-size MAC CE, and a MAC sub-PDU including MAC CE 2 includes an R/F/LCID/L sub-header. and a variable-size MAC CE. In addition, the MAC sub-PDU including the MAC SDU includes an R/F/LCID/L sub-header and a MAC SUD.

As shown in FIG. 4C, MAC CEs, for example, MAC CE 1 and MAC CE 2 are co-located, and the MAC sub-PDU(s) containing the MAC CE(s) are the MAC sub-PDU(s) containing the MAC SDU. It is placed after the PDU and before the MAC sub-PDU including padding. Here, the size of the padding may be zero.

4b and 4c, the LCID included in the subheader of the MAC layer, that is, the logical channel ID (logical channel ID) or the extended logical channel ID (eLCID), of the transmitted MAC SDU or MAC CE You can indicate the type, etc. The mapping of the index of the LCID and the type of the MAC SDU or MAC CE may be shown in Table A below as an example, and the mapping of the index of the eLCID and the type of the MAC SDU or MAC CE may be shown in Table B below, for example. can indicate In various embodiments of the present disclosure, The LCID is an instance of a logical channel of a MAC SDU, a type of MAC CE, a downlink shared channel (DL-SCH) and an uplink shared channel (UL-SCH) padding ( padding) information. One LCID is mapped per MAC subheader, and the LCID may be implemented with 6 bits, for example.

[Table A] LCID values for DL-SCH

[Table B] eLCID values for DL-SCH

5 is a diagram illustrating an example of a process in which one transport block is divided into several code blocks and a CRC is added.

Referring to FIG. 5, a CRC 503 may be added to the end or front of one transport block (TB, 501) to be transmitted in uplink or downlink. The CRC 503 may have 16 bits or 25 bits, or a pre-fixed number of bits, or may have a variable number of bits according to channel conditions, etc., and may be used to determine whether channel coding is successful. The block to which the CRC 503 is added to the TB 501 may be divided into several codeblocks (CBs) 507, 509, 511, and 513 (505). Here, the maximum size of the code blocks may be pre-determined and divided. In this case, the last code block 513 may have a smaller size than the other code blocks 507, 509, and 511. However, this is just an example, and according to another example, 0, a random value, or 1 is inserted into the last code block 513 so that the last code block 513 and the other code blocks 507, 509, and 511 have the same length. can be tailored

In addition, CRCs 517, 519, 521, and 523 may be added to the code blocks 507, 509, 511, and 513, respectively (515). The CRC may have 16 bits or 24 bits or a pre-fixed number of bits, and may be used to determine whether channel coding is successful.

에 대해, CRC

는

를 gCRC24A(D)로 나누어 나머지가 0이 되는 값으로,

를 결정할 수 있다. 전술한 예에서는 일예로 CRC 길이 L을 24로 가정하여 설명하였지만 CRC 길이 L은 12, 16, 24, 32, 40, 48, 64 등 여러 가지 길이로 결정될 수 있다. To generate the CRC 503, the TB 501 and a cyclic generator polynomial may be used, and the cyclic generator polynomial may be defined in various ways. For example, cyclic generator polynomial gCRC24A(D) for a 24-bit CRC = D ²⁴ + D ²³ + D ¹⁸ + D ¹⁷ + D ¹⁴ + D ¹¹ + D ¹⁰ + D ⁷ + D ⁶ + D ⁵ + D ⁴ + Assuming D ³ + D + 1 and L = 24, TB data

For, CRC

Is

is divided by gCRC24A(D) and the remainder is 0,

can decide In the above example, the CRC length L is assumed to be 24 as an example, but the CRC length L may be determined in various lengths such as 12, 16, 24, 32, 40, 48, and 64.

After the CRC is added to the TB in this process, the TB+CRC can be divided into N CBs 507, 509, 511, and 513. CRCs 517, 519, 521, and 523 may be added to each of the divided CBs 507, 509, 511, and 513 (515). The CRC added to the CB may have a different length from when generating the CRC added to the TB, or a different cyclic generator polynomial may be used to generate the CRC. In addition, the CRC 503 added to the TB and the CRCs 517, 519, 521, and 523 added to the code block may be omitted depending on the type of channel code to be applied to the code block. For example, when an LDPC code is applied to a code block rather than a turbo code, CRCs 517, 519, 521, and 523 to be inserted for each code block may be omitted.

However, even when LDPC is applied, the CRCs 517, 519, 521, and 523 may be added to the code block as it is. Also, when a polar code is used, a CRC may be added or omitted.

As described above in FIG. 5, the maximum length of one code block is determined according to the type of channel coding applied to the TB to be transmitted, and the CRC added to the TB and TB according to the maximum length of the code block is Segmentation may be performed.

In the conventional LTE system, the CRC for CB is added to the divided CB, the data bits and CRC of the CB are encoded with a channel code, coded bits are determined, and a pre-promise for each coded bit As described above, the number of bits to be rate matched was determined.

The size of TB (TBS) in the NR system can be calculated through the following steps.

를 계산한다.

는

로 계산될 수 있다. 여기에서,

는 12이며,

는 PDSCH에 할당된 OFDM 심볼 수를 나타낼 수 있다.

는 같은 CDM 그룹의 DMRS가 차지하는, 한 PRB내의 RE 수이다.

는 상위 시그널링으로 설정되는 한 PRB내의 오버헤드가 차지하는 RE 수이며, 0, 6, 12, 18 중 하나로 설정될 수 있다. 이 후, PDSCH에 할당된 총 RE 수

가 계산될 수 있다.

는

로 계산되며,

는 단말에게 할당된 PRB 수를 나타낸다. Step 1: The number of REs allocated to PDSCH mapping in one PRB in the allocated resource

Calculate

Is

can be calculated as From here,

is 12,

may indicate the number of OFDM symbols allocated to the PDSCH.

is the number of REs in one PRB occupied by DMRSs of the same CDM group.

is the number of REs occupied by overhead in the PRB as long as it is set by higher signaling, and can be set to one of 0, 6, 12, and 18. After this, the total number of REs allocated to PDSCH

can be calculated.

Is

is calculated as,

represents the number of PRBs allocated to the UE.

는

로 계산될 수 있다. 여기에서, R은 코드 레이트이며, Q_m은 변조 오더 (modulation order)이며, 이 값의 정보는 DCI의 MCS 비트필드와 미리 약속된 표를 이용하여 전달될 수 있다. 또한, v는 할당된 레이어의 수이다. 만약

이면, 하기의 단계 3을 통해 TBS가 계산될 수 있다. 이외에는 단계 4를 통해 TBS가 계산될 수 있다. Step 2: Number of Temporary Information Bits

Is

can be calculated as Here, R is a code rate, Q _m is a modulation order, and information of this value can be transmitted using the MCS bit field of DCI and a prearranged table. Also, v is the number of allocated layers. what if

If , TBS may be calculated through step 3 below. Otherwise, TBS may be calculated through step 4.

와

의 수식을 통해

가 계산될 수 있다. TBS는 하기 표 12에서

보다 작지 않은 값 중

에 가장 가까운 값으로 결정될 수 있다. Step 3:

Wow

through the formula of

can be calculated. TBS is in Table 12 below

of values not less than

It can be determined as the closest value to .

[Table 12]

와

의 수식을 통해

가 계산될 수 있다. TBS는

값과 하기 [pseudo-code 1]을 통해 결정될 수 있다. 아래에서 C는 한 TB가 포함하는 코드블록의 수에 해당한다.Step 4:

Wow

through the formula of

can be calculated. TBS

It can be determined through the value and the following [pseudo-code 1]. Below, C corresponds to the number of code blocks included in one TB.

[start pseudo-code 1]

[end of pseudo-code 1]

In the NR system, when one CB is input to the LDPC encoder, parity bits may be added and output. At this time, the amount of parity bits may vary according to the LDCP base graph. The method of sending all parity bits generated by LDPC coding for a specific input is called FBRM (full buffer rate matching), and the method of limiting the number of transmittable parity bits is called LBRM (limited buffer rate matching). can do. When a resource is allocated for data transmission, the LDPC encoder output is made into a circular buffer, and the bits of the created buffer are repeatedly transmitted as many times as the allocated resource. At this time, the length of the circular buffer can be referred to as N _cb . .

는

가 되며,

는

로 주어지며,

은 2/3으로 결정될 수 있다.

을 구하기 위해서는 전술한 TBS를 구하는 방법을 이용하되, 해당 셀에서 단말이 지원하는 최대 레이어 수 및 최대 변조 오더를 가정하며, 최대 변조 오더 Q_m는 해당 셀에서 적어도 하나의 BWP에 대해 256QAM을 지원하는 MCS 테이블을 사용하도록 설정된 경우 8, 설정되지 않았을 경우에는 6(64QAM)으로 가정되고, 코드 레이트는 최대 코드레이트인 948/1024으로 가정되며,

는

로 가정되고

는

으로 가정되어 계산된다.

는 하기의 표 13으로 주어질 수 있다. If the number of all parity bits generated by LDPC coding is N, then N _cb = N in the FBRM method. In the LBRM method,

Is

becomes,

Is

is given as

may be determined as 2/3.

In order to obtain , the above-described method for obtaining TBS is used, but assuming the maximum number of layers and maximum modulation order supported by the terminal in the corresponding cell, the maximum modulation order Q _m supports 256QAM for at least one BWP in the corresponding cell. 8 when the MCS table is set to be used, and 6 (64QAM) when not set, and the code rate is assumed to be the maximum code rate of 948/1024,

Is

is assumed to be

Is

It is calculated assuming that

Can be given in Table 13 below.

[Table 13]

The maximum data rate supported by the UE in the NR system may be determined through Equation 2 below.

[Equation 2]

는 최대 레이어 수,

는 최대 변조 오더,

는 스케일링 지수,

는 부반송파 간격을 의미할 수 있다.

는 1, 0.8, 0.75, 0.4 중 하나의 값을 단말이 보고할 수 있으며,

는 하기의 표 14로 주어질 수 있다. In Equation 2, J is the number of carriers bound by carrier aggregation, Rmax = 948/1024,

is the maximum number of layers,

is the maximum modulation order,

is the scaling exponent,

may mean a subcarrier interval.

The terminal can report one of 1, 0.8, 0.75, and 0.4,

Can be given in Table 14 below.

[Table 14]

는 평균 OFDM 심볼 길이이며,

는

로 계산될 수 있고,

는 BW(j)에서 최대 RB 수이다.

는 오버헤드 값으로, FR1 (6 GHz 이하 대역)의 하향링크에서는 0.14, 상향링크에서는 0.18로 주어질 수 있으며, FR2 (6 GHz 초과 대역)의 하향링크에서는 0.08, 상향링크에서는 0.10로 주어질 수 있다. 식 2를 통해 30 kHz 부반송파 간격에서 100 MHz 주파수 대역폭을 갖는 셀에서의 하향링크에서의 최대 데이터율은 하기의 표 15로 계산될 수 있다. In addition,

is the average OFDM symbol length,

Is

can be calculated as,

is the maximum number of RBs in BW(j).

is an overhead value, which may be given as 0.14 in the downlink of FR1 (band below 6 GHz), 0.18 in uplink, 0.08 in downlink of FR2 (band exceeding 6 GHz), and 0.10 in uplink. Through Equation 2, the maximum data rate in downlink in a cell having a frequency bandwidth of 100 MHz at a subcarrier spacing of 30 kHz can be calculated as Table 15 below.

[Table 15]

On the other hand, the actual data rate that can be measured in actual data transmission by the terminal may be a value obtained by dividing the amount of data by the data transmission time. This may be a value obtained by dividing the sum of TBS in 1 TB transmission or TBS in 2 TB transmission by the TTI length. For example, as in the assumption of Table 15, the maximum actual data rate in downlink in a cell having a frequency bandwidth of 100 MHz at a subcarrier interval of 30 kHz can be determined as shown in Table 16 below according to the number of allocated PDSCH symbols.

[Table 16]

Through Table 15, the maximum data rate supported by the terminal can be checked, and through Table 16, the actual data rate according to the allocated TBS can be checked. In this case, there may be a case where the actual data rate is greater than the maximum data rate according to scheduling information.

In a wireless communication system, in particular, a New Radio (NR) system, a data rate that a terminal can support may be mutually agreed upon between a base station and a terminal. This may be calculated using the maximum frequency band supported by the UE, the maximum modulation order, and the maximum number of layers. However, the calculated data rate may differ from the value calculated from the transport block size (TBS) and transmission time interval (TTI) length of the transport block (TB) used for actual data transmission.

Accordingly, a UE may be allocated a TBS larger than a value corresponding to a data rate supported by the UE. To prevent this, there may be restrictions on TBS that can be scheduled according to the data rate supported by the UE.

6 is a diagram showing how a synchronization signal (SS) and a physical broadcast channel (PBCH) of an NR system are mapped in the frequency and time domains.

A primary synchronization signal (PSS, 601), a secondary synchronization signal (SSS, 603), and PBCH are mapped over 4 OFDM symbols, PSS and SSS are mapped to 12 RBs, and PBCH is 20 RBs. The table of FIG. 6 shows how the frequency band of 20 RBs changes according to the subcarrier spacing (SCS). A resource region in which the PSS, SSS, and PBCH are transmitted may be referred to as an SS/PBCH block (SS/PBCH block). Also, the SS/PBCH block may be referred to as an SSB block.

7 is a diagram illustrating symbols in which SS/PBCH blocks can be transmitted according to subcarrier intervals.

Referring to FIG. 7, the subcarrier interval may be set to 15 kHz, 30 kHz, 120 kHz, 240 kHz, etc., and the position of a symbol where an SS/PBCH block (or SSB block) may be located may be determined according to each subcarrier interval. FIG. 7 shows positions of symbols in which SSBs can be transmitted according to subcarrier intervals in symbols within 1 ms, and SSBs do not always have to be transmitted in the area shown in FIG. 7 . The location where the SSB block is transmitted may be configured in the UE through system information or dedicated signaling.

Since the terminal is generally far from the base station, the signal transmitted from the terminal is received by the base station after a propagation delay. The propagation delay time is a value obtained by dividing a path through which radio waves are transmitted from the terminal to the base station by the speed of light, and may generally be a value obtained by dividing the distance from the terminal to the base station by the speed of light. In one embodiment, in the case of a terminal located 100 km away from a base station, a signal transmitted from the terminal is received by the base station after about 0.34 msec. Conversely, the signal transmitted from the base station is also received by the terminal after about 0.34 msec. As described above, the time at which the signal transmitted from the terminal arrives at the base station may vary depending on the distance between the terminal and the base station. Therefore, if several terminals existing in different locations simultaneously transmit signals, their arrival times at the base station may be different. In order to solve this problem and allow signals transmitted from multiple terminals to arrive at the base station at the same time, the uplink signal transmission time may be different for each terminal according to its location. In 5G, NR and LTE systems, this is called timing advance.

8 is a diagram illustrating a processing time of a UE according to a timing advance when a UE receives a first signal and transmits a second signal for the UE in a 5G or NR system according to an embodiment disclosed herein.

Hereinafter, the processing time of the terminal according to the timing advance will be described in detail. When the base station transmits uplink scheduling grant (UL grant) or downlink control signal and data (DL grant and DL data) to the terminal in slot n 802, the terminal receives uplink scheduling grant or downlink scheduling grant in slot n 804 It can receive link control signals and data. At this time, the terminal may receive the signal later than the time at which the base station transmits the signal by a transmission delay time (T _p , 810). In this embodiment, when the terminal receives the first signal in slot n 804, the terminal transmits the corresponding second signal in slot n+4 806. Even when the terminal transmits a signal to the base station, in order to arrive at the base station at a specific time, the terminal performs uplink at timing 806 advanced by a timing advance (TA, 812) from slot n + 4 of the received signal standard. HARQ ACK/NACK for data or downlink data may be transmitted. Therefore, in this embodiment, the time that the UE can prepare to receive uplink scheduling approval and transmit uplink data or receive downlink data and transmit HARQ ACK or NACK is TA at a time corresponding to 3 slots It may be a time excluding (814).

To determine the above-described timing, the base station may calculate the absolute value of the TA of the corresponding terminal. When the terminal initially accesses, the base station can calculate the absolute value of the TA by adding or subtracting the TA value first transmitted to the terminal in the random access step and then the amount of change in the TA value transmitted through higher signaling. have. In the present disclosure, the absolute value of TA may be a value obtained by subtracting the start time of the n-th TTI received by the terminal from the start time of the n-th TTI transmitted by the terminal.

Meanwhile, one of the important criteria for cellular wireless communication system performance is packet data latency. To this end, in the LTE system, transmission and reception of signals are performed in units of subframes having a transmission time interval (TTI) of 1 ms. In the LTE system operating as described above, it is possible to support a terminal (short-TTI UE) having a transmission time period shorter than 1 ms. Meanwhile, in a 5G or NR system, the transmission time interval may be shorter than 1 ms. Short-TTI terminals are suitable for services such as Voice over LTE (VoLTE) service and remote control where latency is important. In addition, the short-TTI terminal becomes a means for realizing the mission critical internet of things (IoT) on a cellular basis.

In a 5G or NR system, when a base station transmits a PDSCH including downlink data, a DCI for scheduling the PDSCH indicates a K1 value corresponding to timing information for transmitting HARQ-ACK information of the PDSCH by the terminal. The terminal may transmit the HARQ-ACK information to the base station when it is not instructed to transmit the HARQ-ACK information before symbol L1, including timing advance. That is, HARQ-ACK information may be transmitted from the terminal to the base station at a time equal to or later than symbol L1, including timing advance. If the HARQ-ACK information is instructed to be transmitted earlier than the symbol L1 including timing advance, the HARQ-ACK information may not be valid HARQ-ACK information in HARQ-ACK transmission from the terminal to the base station.

이후에 순환 전치(cyclic prefix, CP)가 시작하는 첫 번째 심볼일 수 있다.

는 아래의 식 3과 같이 계산될 수 있다.Symbol L1 is from the last point of PDSCH

It may be the first symbol starting with a cyclic prefix (CP) thereafter.

can be calculated as in Equation 3 below.

[Equation 3]

In Equation 3 above, N ₁ , d _1,1 , d _1,2 , κ, μ, and TC may be defined as follows.

- When HARQ-ACK information is transmitted through PUCCH (uplink control channel), d _1,1 = 0, and when transmitted through PUSCH (uplink shared channel, data channel), d ₁ , 1 = 1.

- When a terminal receives a plurality of activated configuration carriers or carriers, the maximum timing difference between carriers may be reflected in the second signal transmission.

- In the case of PDSCH mapping type A, that is, when the location of the first DMRS symbol is the 3rd or 4th symbol of the slot, if the location index i of the last symbol of the PDSCH is less than 7, it is defined as d _1,2 =7-i do.

- In the case of PDSCH mapping type B, that is, when the first DMRS symbol position is the first symbol of PDSCH, if the length of PDSCH is 4 symbols, d _1,2 =3, and if the length of PDSCH is 2 symbols, d _1,2 = 3 + d, where d is the number of overlapping symbols of the PDSCH and the PDCCH including the control signal for scheduling the PDSCH.

- N ₁ is defined according to μ as shown in Table 17 below. μ=0, 1, 2, and 3 mean subcarrier spacings of 15 kHz, 30 kHz, 60 kHz, and 120 kHz, respectively.

[Table 17]

- As for the N ₁ value provided in Table 17 described above, different values may be used depending on UE capabilities.

로 각각 정의된다.-

are defined respectively.

In addition, in 5G or NR systems, when the base station transmits control information including uplink scheduling grant, the terminal may indicate a K2 value corresponding to timing information for transmitting uplink data or PUSCH.

When the PUSCH is not instructed to be transmitted earlier than the symbol L2 by including timing advance, the terminal may transmit the PUSCH to the base station. That is, the PUSCH may be transmitted from the terminal to the base station at a time equal to or later than symbol L2, including timing advance. When the PUSCH is instructed to be transmitted earlier than the symbol L2 including timing advance, the UE can ignore uplink scheduling grant control information from the base station.

이후에 전송해야하는 PUSCH 심볼의 CP가 시작하는 첫 번째 심볼일 수 있다.

는 아래의 식 4와 같이 계산될 수 있다.Symbol L2 is from the last time of the PDCCH including the scheduling grant.

It may be the first symbol starting with the CP of the PUSCH symbol to be transmitted later.

can be calculated as in Equation 4 below.

[Equation 4]

In Equation 4 above, N ₂ , d _2,1 , κ, μ, and T _C may be defined as follows.

- If the first symbol among PUSCH allocated symbols includes only DMRS, d _2,1 = 0, otherwise d ₂ , 1 = 1.

- If the UE is configured with a plurality of active configuration carriers or carriers, the maximum timing difference between the carriers may be reflected in the second signal transmission.

- N ₂ is defined according to μ as shown in Table 18 below. μ=0, 1, 2, and 3 mean subcarrier spacings of 15 kHz, 30 kHz, 60 kHz, and 120 kHz, respectively.

[Table 18]

- For the N ₂ value provided in Table 18 described above, different values may be used depending on UE capabilities.

로 각각 정의한다.-

each defined as

On the other hand, the 5G or NR system may set a frequency band part (BWP) within one carrier to designate a specific terminal to transmit and receive within the set BWP. This may be aimed at reducing power consumption of the terminal. The base station may set a plurality of BWPs, and may change an activated BWP in control information. The time that the terminal can use when the BWP is changed may be defined as shown in Table 19 below.

[Table 19]

In Table 19, frequency range FR1 means a frequency band of 6 GHz or less, and frequency range FR2 may mean a frequency band of 6 GHz or more, and may be classified as shown in Table 4. In general, FR2 means a high-frequency band close to the mmWave band, and FR1 means a relatively low-frequency band compared to FR2. In the above-described embodiment, Type 1 and Type 2 may be determined according to UE capabilities. Scenarios 1, 2, 3 and 4 in the above-described embodiment are given as Table 20 below.

[Table 20]

9 is a diagram illustrating an example of scheduling and transmitting data (eg, TB) according to slots, receiving HARQ-ACK feedback for the corresponding data, and performing retransmission according to the feedback. In FIG. 9, TB1 (900) is initially transmitted in slot 0 (902), and ACK/NACK feedback (904) for this is transmitted in slot 4 (906). If initial transmission of TB1 fails and NACK is received, retransmission 910 for TB1 may be performed in slot 8 908 . In the above, the timing at which ACK/NACK feedback is transmitted and the timing at which retransmission is performed may be predetermined or may be determined according to values indicated in control information or/and higher layer signaling.

FIG. 9 shows an example in which data are sequentially scheduled and transmitted from slot 0 to TB1 to TB8 according to the slot. For example, HARQ process IDs 0 to 7 may be assigned to TB1 to TB8 and transmitted. If the number of HARQ process IDs that can be used by the base station and the terminal is only 4, it may not be possible to continuously transmit to 8 different TBs.

10 is a diagram showing an example of a communication system using satellites. For example, when the terminal 1001 transmits a signal to the satellite 1003, the satellite 1003 transmits the signal to the base station 1005, and the base station 1005 processes the received signal for subsequent operations. A signal including the request is transmitted to the terminal 1001, which can be transmitted again through the satellite 1003. Since the distance between the terminal 1001 and the satellite 1003 is long and the distance between the satellite 1003 and the base station 1005 is also long, the time required for data transmission and reception from the terminal 1001 to the base station 1005 is consequently long. this gets longer

11 is a diagram illustrating the earth orbit period of a communication satellite according to the altitude or height of the satellite. Satellites for communication can be classified into Low Earth Orbit (LEO), Middle Earth Orbit (MEO), and Geostationary Earth Orbit (GEO) satellites according to the orbit of the satellite. In general, GEO 1100 means a satellite at an altitude of about 36000 km, MEO 1110 means a satellite at an altitude of 5000 to 15000 km, and LEO means a satellite at an altitude of 500 to 1000 km. The Earth's orbital period varies according to each altitude. In the case of the GEO (1100), the Earth's orbital period is approximately 24 hours, in the case of the MEO (1110), approximately 6 hours, and in the case of the LEO (1130), approximately 90 to 120 minutes. Low-orbit (~2,000 km) satellites have relatively low propagation delay (which can be understood as the time it takes for a signal transmitted from a transmitter to reach a receiver) and loss at a relatively low altitude, and geostationary-orbit (36,000 km) satellites advantageous in comparison

12 is a diagram showing a conceptual diagram of satellite-terminal direct communication. A satellite 1200 located at an altitude of 100 km or more by a rocket transmits and receives signals to and from a terminal 1210 on the ground, and also connects to a ground station 1220 connected to DU farms 1230 on the ground. send and receive signals

13 is a diagram illustrating a utilization scenario of satellite-terminal direct communication. Satellite-to-device direct communication is a form of supplementing the coverage limit of the terrestrial network, and it is possible to support communication services for specialized purposes. For example, by implementing a satellite-terminal direct communication function in a user terminal, it is possible to send and receive emergency rescue or/and disaster signals of the user in a place that is not covered by terrestrial network communication (1300), and land network such as ship or/and air Mobile communication services for users in areas where communication is not possible can be provided (1310), and the location of ships, trucks, or / and drones can be tracked and controlled in real time without border restrictions (1320), In addition, by supporting the satellite communication function to the base station, it is possible to use the satellite communication to perform the backhaul function (1330) when the base station functions as a backhaul of the base station and is physically far away.

FIG. 14 is a diagram illustrating an example of calculating an expected data throughput in uplink when a LEO satellite at an altitude of 1200 km and a terminal on the ground perform direct communication. In uplink, when the effective isotropic radiated power (EIRP) of the terrestrial terminal is 23 dBm, the path loss of the radio channel to the satellite is 169.8 dB, and the satellite receiving antenna gain is 30 dBi, achievable signal The signal-to-noise ratio (SNR) is estimated at -2.63 dB. In this case, path loss may include path loss in outer space, loss in the atmosphere, and the like. Assuming that the signal-to-interference ratio (SIR) is 2 dB, the signal-to-interference and noise ratio (SINR) is calculated as -3.92 dB, at 30 kHz When using the subcarrier spacing and frequency resources of 1 PRB, it may be possible to achieve a transmission rate of 112 kbps.

FIG. 15 is a diagram showing an example of calculating expected data throughput in uplink when a GEO satellite at an altitude of 35,786 km and a terminal on the ground perform direct communication. If the transmit power EIRP of the terrestrial terminal in uplink is 23 dBm, the path loss of the radio channel to the satellite is 195.9 dB, and the satellite receiving antenna gain is 51 dBi, the achievable SNR is estimated to be -10.8 dB do. In this case, path loss may include path loss in outer space, loss in the atmosphere, and the like. Assuming that the SIR is 2 dB, the SINR is calculated as -11 dB. At this time, if a 30 kHz subcarrier spacing and a frequency resource of 1 PRB are used, a transmission rate of 21 kbps can be achieved. may be a result.

16 is a diagram illustrating path loss values according to a path loss model between a terminal and a satellite, and path loss according to a path loss model between a terminal and a terrestrial communication base station. In FIG. 16, d corresponds to the distance and f _c is the frequency of the signal. In free space, where communication between the terminal and the satellite is performed, the path loss (FSPL, 1600) is inversely proportional to the square of the distance, but in the case where communication between the terminal and the terrestrial gNB is performed, The path loss (PL ₂ , PL' _Uma-NLOS , 1610, 1620) on the ground in the presence of air is almost inversely proportional to the fourth power of the distance. d _3D means the straight-line distance between the terminal and the base station, h _BS is the height of the base station, and h _UT is the height of the terminal. d' _BP = 4 xh _BS xh _UT xf _c / c. fc is the center frequency in Hz, and c is the speed of light in m/s.

In satellite communications (or Non-Terrestrial Network, NTN), a Doppler shift, that is, a frequency shift (offset) of a transmission signal, occurs as a satellite continuously and rapidly moves.

FIG. 17 is a diagram showing formulas and results for calculating the amount of Doppler shift experienced by a signal transmitted from a satellite according to the altitude and location of a satellite and the location of a terminal user on the ground when a signal transmitted from a satellite is received by a ground user. where R is the Earth's radius, h is the altitude of the satellite, v is the speed at which the satellite orbits the Earth, and f _c is the frequency of the signal. The speed of the satellite can be calculated from the altitude of the satellite, which is the speed at which gravity, which is the force of the earth pulling the satellite, and the centripetal force generated as the satellite orbits are equal, which can be calculated as shown in FIG. 18 . 18 is a diagram showing the velocity of a satellite calculated from the altitude of the satellite. As can be seen in FIG. 17, since the angle α is determined by the elevation angle θ, the Doppler shift value is determined according to the elevation angle θ.

19 is a diagram illustrating a Doppler shift experienced by different terminals in one beam transmitted from a satellite to the ground. In FIG. 19, Doppler shifts experienced by terminal 1 (1900) and terminal 2 (1910) according to the elevation angle θ are calculated respectively. This is the result assuming a center frequency of 2 GHz, a satellite altitude of 700 km, a beam diameter of 50 km on the ground, and a terminal speed of 0. In addition, the Doppler shift calculated in the present invention ignores the effect of the earth's rotation speed, and since it is slower than the satellite's speed, the effect can be considered small.

20 is a diagram illustrating a difference in Doppler shift occurring within one beam according to a position of a satellite determined from an elevation angle. It can be seen that the difference in Doppler shift within the beam (or cell) is the largest when the satellite is located directly above the beam, that is, when the elevation angle is 90 degrees. This may be because Doppler shift values at one end of the beam and at the other end have positive and negative values, respectively, when the satellite is above the center.

On the other hand, in satellite communication, a large delay occurs compared to terrestrial network communication because the satellite is far from the user on the ground.

21 is a diagram illustrating a delay time from a terminal to a satellite and a round-trip delay time between a terminal and a satellite-base station according to a position of a satellite determined according to an altitude angle. 2100 is the delay time from the terminal to the satellite, and 2110 is the round-trip delay time between the terminal-satellite-base station. At this time, it is assumed that the delay time between the satellite and the base station is equal to the delay time between the terminal and the satellite. 22 is a diagram illustrating a maximum difference value of a round-trip delay time depending on a user's position within one beam. For example, when the beam radius (or cell radius) is 20 km, it can be seen that the difference in round-trip delay time to the satellite experienced differently by terminals at different positions in the beam according to the position of the satellite is about 0.28 ms or less. have.

In satellite communication, when a terminal transmits and receives a signal to and from a base station, the signal may be transmitted through a satellite. That is, in downlink, the satellite receives the signal transmitted by the base station to the satellite and then transmits the signal to the terminal, and in the uplink, the satellite receives the signal transmitted by the terminal and transmits the signal to the base station. can do. In the above, the satellite may transmit the signal after performing frequency shift as it is after receiving the signal, or it may be possible to transmit the signal after performing signal processing such as decoding and re-encoding based on the received signal.

In the case of LTE or NR, the terminal may access the base station through the following procedure.

- Step 1: The terminal receives a synchronization signal (or SSB (synchronization signal block), which may include a broadcast signal) from the base station. The synchronization signal may include a primary synchronization signal (PSS), a secondary synchronization signal (SSS), and a physical broadcast channel (PBCH). The synchronization signal may include information such as a slot boundary of a signal transmitted by a base station, a frame number, downlink, and uplink settings. In addition, through the synchronization signal, the terminal can obtain subcarrier offset, scheduling information for transmitting system information, and the like.

- Step 2: The terminal receives system information (System Information Block: SIB) from the base station. The SIB may include information for performing initial access and random access. The information for performing the random access may include resource information for transmitting a random access preamble.

- Step 3: A random access preamble (or message 1, msg1) is transmitted to the random access resource set in step 2. The preamble may be a signal determined based on the information set in step 2 using a predetermined sequence. The base station receives the preamble transmitted by the terminal. The base station tries to receive the preamble set in the resource set by the base station without knowing which terminal has transmitted the preamble, and if the reception is successful, it can know that at least one terminal has transmitted the preamble.

- Step 4: When the preamble is received in step 3, the base station transmits a random access response (RAR, or message 2, msg2) as a response thereto. The terminal that has transmitted the random access preamble in step 3 may attempt to receive the RAR transmitted by the base station in this step. The RAR is transmitted on the PDSCH, and the PDCCH scheduling the PDSCH is transmitted together or in advance. A scrambled CRC with a RA-RNTI value is added to the DCI for scheduling the RAR, and the DCI (and CRC) is channel-coded and then mapped to the PDCCH and transmitted. The RA-RNTI may be determined based on time and frequency resources through which the preamble in step 3 is transmitted.

The maximum time limit until the terminal transmitting the random access preamble in step 3 receives the RAR in this step can be set in the SIB transmitted in step 2. This may be limited and set to, for example, 10 ms or 40 ms at most. That is, if the terminal that has transmitted the preamble in step 3 does not receive the RAR within the time determined based on the set maximum time of 10 ms, for example, it may transmit the preamble again. The RAR may include scheduling information for allocating resource of a signal to be transmitted by the terminal in the next step, step 5.

23 is a diagram showing an example of the RAR information structure (MAC payload). This may be the MAC payload format of Msg B (fallback RAR). The RAR 2300 may be, for example, a MAC PDU, and may also include information 2310 on timing advance (TA) to be applied by the terminal and a temporary C-RNTI value 2320 to be used from the next step.

* R field: As a reserved bit, it can be set to “0” as an example.

* Timing Advanced Command field 2310: The timing advance command field indicates an index value T _A used to control the amount of timing adjustment to be applied by the MAC entity. The size of the timing advance command field is, for example, 12 bits.

* UL Grant field: The UL grant field indicates resources to be used in uplink, and the size of the UL grant field is, for example, 27 bits.

* Temporary C-RNTI field 2320: The temporary C-RNTI field indicates a temporary identifier used by a MAC entity during random access, and the size of the temporary C-RNTI field is, for example, 16 bits.

- Step 5: The terminal receiving the RAR in step 4 transmits message 3 (msg3) to the base station according to the scheduling information included in the RAR. The terminal may transmit msg3 including its unique ID value. The base station may attempt to receive msg3 according to the scheduling information transmitted by the base station in step 4.

- Step 6: The base station receives msg3, checks the ID information of the terminal, generates message 4 (msg4) including the ID information of the terminal, and transmits it to the terminal. After transmitting msg3 in step 5, the terminal can attempt to receive msg4 to be transmitted in step 6 thereafter. After receiving Msg4, the terminal can compare the ID value included in msg4 with the ID value transmitted by itself in step 5 after decoding to determine whether msg3 transmitted by itself has been received by the base station. There may be a restriction on the time from when the terminal transmits msg3 in step 5 to receiving msg4 in this step, and this maximum time can also be set from the SIB in step 2.

When the initial access procedure using the above steps is applied to satellite communication, propagation delay time required in satellite communication may become a problem. For example, in step 3, the terminal transmits a random access preamble (or PRACH preamble), and in step 4, the period during which the RAR can be received (random access window), that is, the maximum time required for reception is ra-ResponseWindow It can be set through, and in a conventional LTE or 5G NR system, this maximum time can be set up to about 10 ms.

24 is a diagram showing an example of the relationship between PRACH preamble configuration resources of an LTE system and RAR reception time, and FIG. 25 is a diagram showing an example of the relationship between PRACH preamble configuration resources and RAR reception time of a 5G NR system. Referring to FIG. 24, in the case of LTE, a random access window 2410 starts 3 ms after PRACH (random access preamble) is transmitted (2400), and the terminal receives (2420) RAR within the random access window. In this case, it may be determined that transmission of the PRACH preamble is successful. Referring to FIG. 25 , in the case of NR, a random access window 2510 starts from a control information area for RAR scheduling that appears first after PRACH (Random Access Preamble) is transmitted (2500). When the UE receives the RAR within the random access window (2520), it may be determined that the transmission of the PRACH preamble is successful.

로 정해지며, 여기에서

Hz 와

이다. 또한,

로,

,

,

로 각각 정의될 수 있다. As an example, a TA for uplink transmission timing in a 5G NR system may be determined as follows. first

is determined, where

Hz and

to be. In addition,

as,

,

,

can be defined respectively.

만큼 앞당겨서 상향링크 전송을 수행할 수 있다. 상기에서

의 값은 RAR을 통해 전달되거나 또는 MAC CE에 기반하여 결정될 수 있으며,

는 단말에게 설정되거나, 미리 정해진 값에 기반하여 결정되는 값일 수 있다. 26 is a diagram showing an example of downlink frame and uplink frame timing in a terminal. The terminal selects an uplink frame based on the time of the downlink frame.

It is possible to perform uplink transmission by advancing by as much as . from above

The value of may be transmitted through RAR or determined based on MAC CE,

may be a value set in the terminal or determined based on a predetermined value.

값을 지시해줄 수 있으며, 이 때,

는 0, 1, 2, ..., 3846 중 하나의 값을 지시해주는 것일 수 있다. 이 경우, RAR의 부반송파 간격(subcarrier spacing; SCS)가

kHz이면,

는

로 결정된다. 단말이 랜덤 엑세스 과정을 완료한 이후에는 기지국으로부터 TA의 변화값을 지시받을 수 있으며, 이는 MAC CE 등을 통해 지시될 수 있다. MAC CE를 통해 지시되는

정보는 0, 1, 2, ..., 63 중 하나의 값을 지시해줄 수 있으며, 이는 기존 TA 값에 가감되어 새로운 TA 값을 계산하는데 사용되며, 이 결과 TA 값은

와 같이 새롭게 계산될 수 있다. 이렇게 지시된 TA 값은 일정 시간 이후부터 단말이 상향링크 전송에 적용할 수 있다. In RAR of 5G NR system,

You can indicate a value, and at this time,

may indicate one of 0, 1, 2, ..., 3846. In this case, the subcarrier spacing (SCS) of RAR is

If kHz,

Is

is determined by After the UE completes the random access process, it may receive an indication of a change value of TA from the base station, which may be indicated through a MAC CE or the like. Directed via MAC CE

The information may indicate a value of 0, 1, 2, ..., 63, which is added to or subtracted from the existing TA value and used to calculate a new TA value, and the resulting TA value is

can be newly calculated as The TA value indicated in this way can be applied to uplink transmission by the UE after a certain time.

FIG. 27A is a diagram illustrating an example of continuous motion of a satellite on the ground of the earth or in a terminal located on the earth as the satellite revolves around the earth along a satellite orbit. Since the distance between the terminal and the satellite varies according to the elevation angle at which the terminal views the satellite, a propagation delay between the terminal, the satellite, and the base station varies.

27B is a diagram showing an example of the structure of an artificial satellite. A satellite includes a solar panel or solar array (2700) for photovoltaic or solar power generation, a main mission antenna (2710) for communication with a terminal, and a feeder link antenna (2720) for communication with a ground station. ), a transmission/reception antenna (inter-satellite link) 2730 for inter-satellite communication, and a processor for controlling transmission/reception and performing signal processing. In the above case where inter-satellite communication is not supported depending on the satellite, an antenna for inter-satellite signal transmission/reception may not be disposed. In FIG. 27B, it is shown that the L band of 1 to 2 GHz is used for communication with the terminal, but the high-frequency bands K band (18 to 26.5 GHz), Ka band (26.5 to 40 GHz), and Ku band (12 to 18 GHz) ) may also be used.

In addition, in various embodiments of the present disclosure, the term “base station (BS)” refers to a transmit point (TP), a transmit-receive point (TRP), Radio, such as an enhanced node B (eNodeB or eNB), 5G base station (gNB), macrocell, femtocell, WiFi access point (AP), or other wirelessly enabled devices Can represent any component (or set of components) that is configured to provide access. The base stations are one or more radio protocols, for example, 5G 3GPP new air interface / access (NR), long term evolution (LTE), LTE advanced (LTE-A), high-speed packet access (high speed packet access: HSPA), wireless access according to Wi-Fi 802.11a/b/g/n/ac, etc. may be provided.

In addition, in various embodiments of the present disclosure, the term “terminal” includes “user equipment (UE),” “mobile station,” “subscriber station,” “remote terminal,” It can refer to any component such as “wireless terminal”, “receive point”, or “user device”. For convenience, the term “terminal” means that the terminal is a mobile device ( Used in various embodiments of the present disclosure to indicate a device that accesses a base station, whether it is a mobile phone or smart phone) or whether it should be considered a stationary device (eg a desktop computer or vending machine) do.

Also, in various embodiments of the present disclosure, the term "TA" may be used interchangeably with "TA information", "TA value", or "TA index".

In various embodiments of the present disclosure, data or control information transmitted from a base station to a terminal may be referred to as a first signal, and an uplink signal related to the first signal may be referred to as a second signal. For example, the first signal may include DCI, UL grant, PDCCH, PDSCH, RAR, and the like, and the second signal associated with the first signal may include PUCCH, PUSCH, msg 3, and the like.

Also, there may be an association between the first signal and the second signal. For example, when the first signal is a PDCCH including a UL grant for scheduling uplink data, the second signal corresponding to the first signal may be a PUSCH including uplink data. Meanwhile, a gap between transmission and reception times of the first signal and the second signal may be a predetermined value between the terminal and the base station. Unlike this, the difference between the transmission and reception time of the first signal and the second signal may be determined by an instruction from the base station or a value transmitted through upper signaling.

In direct terminal-satellite communication, since the distance between the terminal and the satellite and the satellite-base station is long and the satellite continuously moves, when the signal transmitted by the base station or terminal is received by the terminal or base station, time offset occurs due to delay time, etc. will do Accordingly, the present invention provides a method and apparatus in which a base station instructs time offset information and a terminal corrects the time offset information so that the time offset can be corrected. The following embodiments have been described assuming communication between a terminal and a satellite and a ground station, but communication between a satellite base station and a terminal is not excluded. In the present invention, time offset may be used interchangeably with timing advance. Methods and apparatuses provided by various embodiments of the present disclosure may be applied to a terrestrial communication system as well as a satellite communication system.

[First Embodiment]

In the first embodiment of the present disclosure, when a UE transmits an uplink signal to a satellite or a base station, the UE directly determines (eg, calculates) a TA value and applies the determined TA value to a method and apparatus. describe about In addition, in the first embodiment of the present disclosure, the base station or satellite instructs the terminal to a TA value to be applied when the terminal transmits an uplink signal to the satellite or base station, and accordingly, the terminal applies the indicated TA value A method and apparatus for transmitting an uplink signal will be described. In addition, the first embodiment of the present disclosure describes a method and apparatus for adaptively determining a TA value to be applied when a terminal transmits an uplink signal to a satellite or a base station. More specifically, in the first embodiment of the present disclosure, as described in the method for the terminal to determine the TA value by itself and in the present disclosure, the base station or satellite instructs the terminal for the TA value, and the terminal applies the indicated TA value. A method and apparatus for determining a TA value by adaptively selecting one of the following methods are described.

만큼 앞당길 수 있다. 위성 통신을 위한 TA를 위해 계산되는

는 하기 수학식 5와 같이 표현될 수 있다.First, the terminal compares the uplink transmission time with the downlink reception time for uplink synchronization, and based on the comparison result, the uplink transmission time is less than the downlink reception time.

can be advanced as much as Calculated for TA for satellite communications

Can be expressed as in Equation 5 below.

[Equation 5]

는

과 같이 주어질 수 있으며,

Hz 이고,

이다. 상기 수학식 5에서

는 기지국으로부터 수신되는 RAR이나 MAC CE에 포함되는 TA 값 등에 기반하여 결정되는 값이며,

는 미리 고정되거나 약속된 값일 수 있다. 상기 수학식 5에서

는 단말이 단말 자신과 위성의 위치(또는 기준 위치)에 기반하여 측정한 TA 보정값이며,

는 기지국이 상위 시그널링 또는 물리계층 신호를 이용하여 설정하거나 지시한 TA 보정값일 수 있다. In Equation 5 above

Is

can be given as

is Hz,

to be. In Equation 5 above

Is a value determined based on the TA value included in the RAR or MAC CE received from the base station,

may be a pre-fixed or promised value. In Equation 5 above

is a TA correction value measured by the terminal based on the positions (or reference positions) of the terminal itself and the satellite,

may be a TA correction value set or indicated by the base station using higher signaling or a physical layer signal.

와

의 파라미터가 추가된 수식일 수 있다. Equation 5 is compared with Equation 6 below, which is a conventional TA application method.

Wow

It may be an equation in which the parameter of is added.

[Equation 6]

를 정하는 과정의 일례를 도시한 도면이다. 도 27d는 본 발명에서 제공하는 방법으로, 초기접속에서부터 단말이

,

및

를 정하는 과정의 일례를 도시한 도면이다.27c, the terminal from the initial access

It is a diagram showing an example of the process of determining. 27d is a method provided by the present invention, in which a terminal from initial access

,

and

It is a diagram showing an example of the process of determining.

는 RAR이나 msg B에서 전송되는

= 0, 1, 2, ..., 3846에 기반하여,

로 결정될 수 있다. 또한, MAC CE로

= 0, 1, 2,..., 63가 전달되고,

로 업데이트 될 수 있다. 또한,

, RAR이나 msg B에서 전송되는

또는 MAC CE로부터 전송되는

값 등은 통신 시스템에 따라 변경될 수도 있다. 그리고 MAC CE로부터 전송되는

에 기반하여

과 같이 단말이 TA 업데이트를 수행할 경우에, 만일

에 대한 최댓값이 63 보다 큰 경우에

값은 31 보다 크거나 같은 값일 수도 있으며,

에 대한 최댓값이 63 보다 작은 경우에는

값은 31 보다 작거나 같은 값에 기반하여 단말은 상기 업데이트 된

값

를 결정할 수도 있다.

is transmitted in rar or msg b

= 0, 1, 2, ..., based on 3846,

can be determined by Also, with MAC CE

= 0, 1, 2,..., 63 are passed,

can be updated with In addition,

, transmitted in RAR or msg B

or transmitted from MAC CE

Values and the like may be changed depending on the communication system. And transmitted from MAC CE

based on

When the UE performs TA update as in

If the maximum value for is greater than 63

The value may be greater than or equal to 31,

If the maximum value for is less than 63

Based on the value less than or equal to 31, the terminal performs the updated

value

can also decide

Another example of an operation process of a terminal in a communication system according to various embodiments of the present disclosure will be described with reference to FIG. 28 .

28 is a diagram schematically illustrating another example of an operation process of a terminal in a communication system according to various embodiments of the present disclosure.

Referring to FIG. 28, the terminal may perform an initial access procedure according to the process described in FIG. 28 and determine a TA after performing the initial access procedure, which will be described in detail as follows.

First, in operation 2811, the terminal detects a synchronization signal and PBCH block (SSB) received from the base station. In operation 2813, the UE decodes system information blocks (SIBs) based on the detected SSB. Here, the UE can detect information about random access channel (RACH) resources by decoding SIBs.

를 획득할 수 있다. 동작 2817에서 단말은 SIB들을 디코딩함으로써 공통 TA 오프셋, 예를 들어

를 획득한다(또는 디코딩한다). In operation 2815, the terminal acquires (or decodes) satellite information by decoding SIBs. Here, the satellite information may include at least one of various parameters such as location information of the satellite. In operation 2815, the terminal determines a UE-specific TA correction value based on the positions (or reference positions) of the terminal itself and the satellite based on the acquired satellite information, for example.

can be obtained. In operation 2817, the UE decodes the SIBs to obtain a common TA offset, e.g.

Obtain (or decode)

와

에 기반하는 TA들을 계산할 수 있고, 계산된 TA들을 적용하여 기지국으로 PRACH를 송신한다. 동작 2821에서 단말은 PRACH 송신에 대한 응답으로, TA 값을 포함하는 RAR을 수신한다. 동작 2823에서 단말은 수신된 RAR에 기반하여 TA를 조정한다.In operation 2819, the terminal

Wow

TAs based on can be calculated, and the PRACH is transmitted to the base station by applying the calculated TAs. In operation 2821, the UE receives an RAR including a TA value in response to the PRACH transmission. In operation 2823, the UE adjusts the TA based on the received RAR.

In operation 2825, the terminal transmits msg3 to the base station by applying the TA. Here, msg3 represents a message transmitted in UL-SCH, including a C-RNTI MAC CE or CCCH SDU as part of a random access procedure, and may be the first scheduled transmission of the random access procedure. In operation 2827, the terminal receives a MAC CE including a TA adjustment value from the base station. In operation 2829, the UE transmits the PUSCH/PUCCH by applying the TA based on the TA adjustment value included in the MAC CE. In various embodiments of the present disclosure, transmitting the PUSCH/PUCCH may mean transmitting at least one of the PUSCH and the PUCCH.

The operation process of the terminal as described in FIG. 28, that is, the process of performing the initial access procedure and determining the TA after performing the initial access procedure, is compared with the operation process of the terminal in another embodiment of the present disclosure as shown in Table 21 below. can be arranged as

Operation process of terminal Operating process of the terminal based on FIG. 28 1. SSB detection
2. SIBs decoding (RACH resource information detection)
3. PRACH Transmission
4. Receive RAR with TA value
5. Adjust TA based on RAR
6. Send msg3 by applying TA
7. Receive MAC CE containing TA adjustment values
8. PUSCH/PUCCH transmission by applying TA based on TA adjustment value

획득
4. 공통 TA 오프셋 디코딩,

획득
5. TA들을 적용하여 PRACH 송신
6. TA 값을 포함하는 RAR 수신
7. RAR에 기반하여 TA 조정
8. TA를 적용하여 msg3 송신
9. TA 조정 값을 포함하는 MAC CE 수신
10. TA를 적용하여 PUSCH/PUCCH 송신1. SSB detection
2. SIBs decoding (RACH resource information detection)
3. Satellite information (location information, etc.) decoding;

acheive
4. common TA offset decoding;

acheive
5. PRACH transmission by applying TAs
6. Receive RAR with TA value
7. Adjust TA based on RAR
8. Send msg3 by applying TA
9. Receive MAC CE containing TA adjustment values
10. PUSCH/PUCCH transmission by applying TA

In addition, in the operation process of the terminal described in FIG. 28, the order of some operations may be changed. For example, the order of decoding satellite information and decoding a common TA offset may be changed.

Meanwhile, although an operation process of a terminal in a communication system according to various embodiments of the present disclosure has been illustrated with reference to FIG. 28 , various modifications may be made to FIG. 28 , of course. As an example, while successive steps are shown in FIG. 28 , it is understood that the steps described in FIG. 28 may overlap, may occur in parallel, may occur in a different order, or one or more of the steps may occur multiple times. Of course.

Next, with reference to FIG. 29, another example of an operation process of a terminal in a communication system according to various embodiments of the present disclosure will be described.

29 is a diagram schematically illustrating another example of an operation process of a terminal in a communication system according to various embodiments of the present disclosure.

Referring to FIG. 29 , the terminal may perform an initial access procedure according to the process described in FIG. 29 and determine a TA after performing the initial access procedure, which will be described in detail as follows. In particular, the operation process of the terminal described in FIG. 29 is a 2-step operation process of the terminal based on the random access procedure for the 4-step (4-step) random access (RA) type described in FIG. 28 It may be an operation process of a terminal based on a random access procedure for an RA type.

First, in operation 2911, the terminal detects the SSB received from the base station. In operation 2913, the UE decodes SIBs based on the detected SSB. Here, the UE can obtain information on RACH resources by decoding SIBs.

를 획득할 수 있다. 동작 2917에서 단말은 SIB들을 디코딩함으로써 공통 TA 오프셋, 예를 들어

를 획득한다(또는 디코딩한다). In operation 2915, the terminal obtains (or decodes) satellite information by decoding SIBs. Here, the satellite information may include at least one of various parameters such as location information of the satellite. In operation 2915, the terminal determines a UE-specific TA correction value based on the position (or reference position) of the terminal itself and the satellite based on the decoded satellite information, for example.

can be obtained. In operation 2917, the UE decodes the SIBs to obtain a common TA offset, e.g.

Obtain (or decode)

와

에 기반하여 TA들을 계산하고, 계산된 TA들을 적용하여 기지국으로 msgA를 송신한다. 여기서, msgA는 2-단계(2-step) 랜덤 억세스(random access: RA) 타입을 위한 랜덤 억세스 절차의 프리앰블 및 페이로드 송신들일 수 있다. 동작 2921에서 단말은 기지국으로부터 TA 값을 포함하는 msgB를 수신한다. 여기서, msgB는 2-단계 RA 타입을 위한 랜덤 억세스 절차에서 msgA에 대한 응답으로서, contention resolution, fallback indication(들), 및 backoff indication에 대한 응답(들)을 포함할 수 있다. 동작 2923에서 단말은 msgB에 포함된 TA 조정값에 기반하여 TA를 조정한다. 동작 2925에서 단말은 조정된 TA를 적용하여 PUSCH/PUCCH를 송신한다.In operation 2919, the terminal

Wow

TAs are calculated based on , and msgA is transmitted to the base station by applying the calculated TAs. Here, msgA may be preamble and payload transmissions of a random access procedure for a 2-step random access (RA) type. In operation 2921, the terminal receives msgB including a TA value from the base station. Here, msgB is a response to msgA in the random access procedure for the 2-step RA type, and may include contention resolution, fallback indication (s), and response (s) to backoff indication. In operation 2923, the UE adjusts the TA based on the TA adjustment value included in msgB. In operation 2925, the UE transmits the PUSCH/PUCCH by applying the adjusted TA.

The operation process of the terminal as described in FIG. 29, that is, the process of performing the initial access procedure and determining the TA after performing the initial access procedure, is compared with the operation process of the terminal in another embodiment of the present disclosure as shown in Table 22 below. can be arranged as

Operation process of terminal Operating process of the terminal based on FIG. 29 1. SSB detection
2. SIBs decoding (RACH resource information detection)
3. Send MsgA (PRACH + Msg3)
4. Receive MsgB with TA value
5. Adjust TA based on MsgB
6. PUCCH/PUSCH transmission by applying TA

획득
4. 공통 TA 오프셋 디코딩,

획득
5. TA들을 적용하여 MsgA 송신
6. TA 값을 포함하는 MsgB 수신
7. MsgB에 기반하여 TA 조정
8. TA를 적용하여 PUCCH/PUSCH 송신1. SSB detection
2. SIBs decoding (RACH resource information detection)
3. Satellite information (location information, etc.) decoding;

acheive
4. common TA offset decoding;

acheive
5. MsgA transmission by applying TAs
6. Receive MsgB with TA value
7. Adjust TA based on MsgB
8. PUCCH/PUSCH transmission by applying TA

Also, in the operation process of the terminal described in FIG. 29 , the order of some operations may be changed. For example, the order of decoding satellite information and decoding a common TA offset may be changed.

Meanwhile, although an operation process of a terminal in a communication system according to various embodiments of the present disclosure has been disclosed with reference to FIG. 29 , various modifications may be made to FIG. 29 , of course. As an example, although successive steps are shown in FIG. 29 , the steps described in FIG. 29 may overlap, may occur in parallel, may occur in a different order, or one or more of the steps may occur multiple times. to be.

는 단말이 계산하여 적용하는 값이다. 따라서, 기지국은 단말이 계산하는

값을 알지 못할 수 있다. 또한, 이렇게 단말에 의해 계산되는

값은 위성이나 단말의 움직임으로 인해 시간에 따라 바뀔 수 있다. On the other hand, used in the embodiments of the present disclosure

is a value calculated and applied by the terminal. Therefore, the base station calculates

You may not know the value. In addition, calculated by the terminal in this way

The value may change over time due to movement of satellites or terminals.

값을 고려하여 단말의 TA를 제어해야할 필요가 있을 수 있고, 따라서 단말이

값을 업데이트하는 시점을 설정할 필요가 있을 수 있다. 따라서, 단말은 하기와 같은 방법들, 예를 들어 방법T1 내지 방법T6 중 어느 한 방법, 또는 방법T1 내지 방법T6 중 적어도 두 개를 조합하는 방법에 기반하여

값을 업데이트할 수 있다. Thus, in embodiments of the present disclosure, a base station may change over time.

It may be necessary to control the TA of the UE in consideration of the value, so that the UE

You may need to set when to update the value. Therefore, the terminal is based on the following methods, for example, any one of methods T1 to T6, or a method of combining at least two of methods T1 to T6

Values can be updated.

를 업데이트 한다. 방법T1은 단말이 기지국으로부터 SIB가 수신된다고 판단하는 경우에 적용될 수 있거나, 또는 기지국으로부터 SIB 업데이트를 지시하는 페이징(paging) 신호가 수신되는 경우에 적용될 수 있다. -Method T1: The terminal always receives the SIB including satellite information (eg, including satellite information)

update the Method T1 may be applied when the terminal determines that the SIB is received from the base station, or may be applied when a paging signal indicating SIB update is received from the base station.

의 변화율을 별도로 지시할 수 있으며, 또한 TA의 변화율에 따라 TA 값을 다시 계산하는, 일 예로 업데이트하는 주기 및 오프셋을 설정할 수 있다. 이 경우 단말은 상기 주기 및 오프셋에 따라 결정되는 시점에 TA, 예를 들어

를 업데이트하게 되며, 단말이 업데이트하는 TA의 양은 TA의 변화율에 따라 결정될 수 있다. 본 개시의 다양한 실시 예들에서, 기지국은 명시적인(explicit) 방법 또는 암시적인(implicit) 방법에 기반하여 TA의 변화율을 지시할 수 있다. - Method T2: the base station is TA, as an example

The rate of change of may be separately indicated, and a cycle and offset for recalculating the TA value according to the rate of change of TA may be set, for example, updating. In this case, the terminal is a TA at a time determined according to the period and offset, for example

is updated, and the amount of TA updated by the UE may be determined according to the change rate of the TA. In various embodiments of the present disclosure, a base station may indicate a change rate of a TA based on an explicit method or an implicit method.

를 업데이트하는 업데이트 주기 및 오프셋을 설정할 수 있다. 이 경우 단말은 상기 기지국에 의해 설정되는 업데이트 주기 및 오프셋에 따라 결정되는 해당 시점에 TA를 업데이트할 수 있다. 본 개시의 다양한 실시 예들에서, 기지국은 명시적인 방법 또는 암시적인 방법에 기반하여 상기 업데이트 주기 및 오프셋을 지시할 수 있다.-Method T3: The base station determines that the terminal is based on the position of the satellite and the position of the terminal

It is possible to set the update cycle and offset for updating the . In this case, the terminal may update the TA at a point in time determined according to an update period and an offset set by the base station. In various embodiments of the present disclosure, the base station may indicate the update period and offset based on an explicit method or an implicit method.

를 항상 업데이트하여 적용할 수 있다. - Method T4: The UE performs uplink transmission (for example, PUCCH / PUSCH, PRACH, SRS transmission, etc.) at least in some cases at a corresponding time (every time, according to a regular period, or irregularly performed time) all possible), e.g. at the time of the slot

can always be updated and applied.

를 업데이트한다. 일 예로, 단말은 TA 가 만료되는 시점에서,

를 업데이트한다. 상기에서 만료라고 함은 TA 명령에 대한 타이머(timer)에 기반하여 타이머 값이 특정 시점에 도달했음을 의미할 수 있다. 상기 타이머는 timeAlignmentTimer로 설정될 수 있으며, 얼마나 오랜 시간 동안 상향링크 시간 동기가 맞아 있는지에 관한 파라미터일 수 있다. 새로운 TA 명령을 수신하면 단말은 timeAlignmentTimer를 시작하거나 재시작할 수 있다. timeAlignmentTimer가 만료되면 단말은 HARQ 버퍼를 비우고, RRC 설정 등을 새로 할 수 있다. -Method T5: The terminal is based on the expiration time of the TA command transmitted by the base station through the MAC CE

update For example, when the TA expires, the UE

update In the above, expiration may mean that a timer value has reached a specific point in time based on a timer for a TA command. The timer may be set as timeAlignmentTimer and may be a parameter for how long uplink time synchronization is correct. Upon receiving a new TA command, the UE may start or restart timeAlignmentTimer. When the timeAlignmentTimer expires, the UE can empty the HARQ buffer and renew RRC settings.

와 관련된 새로운 타이머 timeAlignmentTimer_UEspecific가 도입되어 단말은 새로운 타이머 timeAlignmentTimer_UEspecific에 기반하여

를 업데이트 할 수 있다. timeAlignmentTimer_UEspecific는 단말이

를 새로 계산하거나, 또는

에 관한 정보를 기지국으로 전송하는 경우 시작 또는 재시작할 수 있다. timeAlignmentTimer_UEspecific가 만료되면 단말은

를 새로 계산하여 업데이트 하거나

를 0으로 설정하거나, 또는 PRACH 송신을 수행할 수 있다. - Method T6:

A new timer related to timeAlignmentTimer_UEspecific is introduced, and the terminal is based on the new timer timeAlignmentTimer_UEspecific

can be updated. timeAlignmentTimer_UEspecific is

is calculated anew, or

When transmitting information about to the base station, it can be started or restarted. When timeAlignmentTimer_UEspecific expires, the UE

update by calculating a new

may be set to 0, or PRACH transmission may be performed.

[Second Embodiment]

A second embodiment provides a method and apparatus for a terminal to deliver (report) a timing advance (TA) value applied or applied by the terminal to a base station or a satellite. In the present invention, a satellite may be an object located high on the ground, and may be a concept including an airplane, an airship, and the like.

The terminal may perform an operation of transmitting the TA value applied by the terminal to the base station. This may be to inform the base station of the applied TA value when the terminal applies the TA value without a separate instruction from the base station, or to check or determine how the terminal applies the TA value indicated by the base station. For example, this operation may be performed so that a satellite newly connected to the terminal checks the TA value of the terminal when the satellite to which the terminal is connected is changed. For example, the terminal may apply the TA calculated based on the positions of the terminal and satellites by itself.

In order for the UE to report the TA value to the BS, one or a combination of at least two of the following methods may be used.

- Method 1: The base station may trigger reporting of the TA value of the terminal through the DCI. The base station may trigger a TA value report through a value of some bitfields of DCI or a combination of values of bitfields. If a field indicating a TA value reporting trigger is included in the DCI, and in this case, when the field of the received DCI is set to a specific value, the UE can understand that the TA value reporting has been triggered. Alternatively, when the value of one or more (for example, other purposes) fields included in the DCI is set to a predetermined value, the UE may understand that the TA value report has been triggered. The UE may transmit the TA value at a specific time point based on the time point at which the DCI is received to the base station.

- Method 2: The base station may trigger reporting of the TA value of the terminal through the MAC CE. The base station may trigger a TA value report by using some bit values or bit field values of the MAC CE, and the terminal transmits the TA value at the time of receiving the MAC CE or at a certain time after receiving the MAC CE to the base station. can be conveyed

- Method 3: The base station may indicate which TA value the terminal should report through RRC configuration. For example, the base station may set a period and offset value for TA reporting or/and a specific condition for the terminal to report the TA value through higher signaling to determine at what point the terminal will report the TA value. In this case, the criterion is The TA value application time (ie, the time when the TA value to be reported is applied, which may be referred to as the TA value reference time point) may also be specified. In the above, the specific condition in which the terminal reports the TA value may be, for example, when the TA value exceeds a certain value or when the distance between the terminal and the satellite exceeds a certain value, and the certain values are set as higher level signaling. It may be information transmitted from the SIB or the like, or may be a fixed value.

- Method 4: The UE may report a TA value without a separate trigger from the BS. For example, method 4 may be that the terminal transmits information indicating a TA value to the base station according to a specific condition, and the specific condition is (without signaling such as DCI, MAC CE, RRC, etc. for a trigger from the base station) A time to report a TA value or a condition for a comparison result between a TA value applied by the UE and a specific threshold may be predetermined.

In the case of transmitting a TA value as described above, the terminal may transmit the TA value using a physical channel such as PUCCH or PUSCH, or transmit the TA value information to the base station through upper signaling. When the UE transmits TA value information using a physical channel, resources to be used for reporting the TA value information may be configured through higher level signaling.

값 또는

값을 보고한다는 것일 수 있다. 또는,

와

중에서 어떤 것을 보고할 지 기지국이 단말에게 SIB 또는 상위 시그널링을 통해 설정할 수 있다. Reporting the TA value above means that in the above equation

value or

It could be reporting a value. or,

Wow

The base station can set which one to report from among them to the terminal through SIB or upper signaling.

The reference time point for determining the TA value reported by the UE and the time point for reporting the TA value may be determined based on a time point at which the UE reports a TA value, a time point when a TA value report is triggered, and the like. For example, when TA value reporting is triggered by DCI in slot n, the terminal may report the TA value applied or calculated in slot n-K, and the terminal reports the TA value to the base station in slot n+N. It is possible. In the above, K and N may be values determined according to subcarrier spacing, UE capability, DL/UL configuration of slots, and PUCCH resource configuration, respectively.

In the above, K may be 0. K = 0 may mean that the UE reports the TA value based on the time point when the TA value reporting triggering signal is received. Also, in the above, K may be a value smaller than 0. In this case, for example, the TA value at the time when the UE reports the TA value may be pre-calculated, and report information may be generated and reported. Also, K can be an integer value greater than zero. This may be that the UE reports the TA value at a time point earlier than the time point at which the UE reports the TA value (for example, slot n+N), which requires time for the UE to encode the information to be reported and prepare for transmission. Therefore, it may be to report the TA value at an early point in time.

30A and 30B are diagrams illustrating an example of an operation of a base station and a terminal for reporting a TA value of a terminal. When reporting the TA value of the present invention, the TA value applied by the terminal may be indicated in units of ms, units of slots, or units of symbols, or may be provided as information including decimal values rather than integers. The report of the TA value of the present invention may include the absolute value of the TA, but the relative TA value excluding the TA value indicated by the previous base station or the predetermined TA value or the amount of change in the TA value (this is, for example, the amount of TA change for a certain period of time) may) and the like.

30A is a diagram illustrating an operation of a base station. The base station transmits configuration information related to TA reporting through upper signaling (3000). This setting information is, for example, information for configuring TA reporting, such as a period and offset for TA reporting, trigger conditions for TA reporting, TA value reference time point information, types of TA information to be reported, and resource setting information for TA reporting to be performed. may include at least one of them. The base station triggers a TA report to the terminal (3010). Such a trigger may be performed, for example, by upper signaling or DCI of the specific content described above, but may also be omitted. The base station receives the TA report transmitted by the terminal according to the transmitted configuration information (3020).

30B is a diagram illustrating an operation of a terminal. The terminal receives configuration information related to the TA report transmitted by the base station through upper signaling (3030). This setting information is, for example, information for configuring TA reporting, such as a period and offset for TA reporting, trigger conditions for TA reporting, TA value reference time point information, types of TA information to be reported, and resource setting information for TA reporting to be performed. may include at least one of them. The terminal receives a signal for triggering a TA report transmitted by the base station (3040). Such a trigger may be performed, for example, by upper signaling or DCI of the specific content described above, but may also be omitted. The UE transmits a TA report according to the received configuration information (3020). For example, when the UE receives TA report resource information, it transmits the TA report in the set resource. Each step disclosed in FIGS. 30A and 30B may be applied in a changed order, and other steps may be added or omitted.

[Third Embodiment]

를 단말이 계산하고 결정하고 보고하는 방법을 제공한다. 상기

값은 단말이 자신 및 NTN(non-terrestrial network) 위성까지의 거리에 기반하여 계산할 수 있을 것이다. 단말이 자신의 위치를 계산하는 것은, 위성 네비게이션 시스템에서 네비게이션 위성들로부터 신호를 전달받아 계산할 수 있으며, 상기 네비게이션 위성은 NTN위성과 다를 수 있다. In the third embodiment, the first and second embodiments have been described.

Provides a method for the terminal to calculate, determine, and report remind

The value may be calculated based on the distance of the terminal to itself and a non-terrestrial network (NTN) satellite. The UE calculates its position by receiving signals from navigation satellites in a satellite navigation system, and the navigation satellites may be different from NTN satellites.

The terminal can estimate a delay time between the satellite and the terminal based on its own location and the position of the satellite, and can perform uplink transmission by correcting the estimated delay time value by itself. For example, a satellite transmits information about the location of the satellite through broadcast information, and a terminal can receive the information about the location of the satellite transmitted by the satellite and compare it with its own location. The location of the terminal itself can be found by utilizing one of several types of Global Positioning System (GPS) systems or information from a base station independently or in a combined manner. The terminal can calculate the uplink transmission time by estimating the time it takes for radio waves to be transmitted to the satellite through the comparison.

For example, when it is assumed that the terminal receives a signal in slot n through downlink at a specific time point and performs uplink transmission corresponding to the signal in slot n+k, the uplink transmission is performed at time slot n+k It can be transmitted earlier by 2*Td. In the above, Td may be a delay time from a terminal to a satellite calculated with location information of satellites and terminals or a value corresponding thereto. The delay time Td may be a value obtained by dividing a distance from a terminal to a satellite or a value corresponding thereto by the speed of light, or a value corresponding thereto. In the above, the position of the satellite may be, for example, a value calculated based on slot n+k in which the terminal performs uplink transmission. This is because the position of the satellite in slot n and the position of the satellite in slot n+k may vary according to the movement of the satellite.

In a terrestrial network, a propagation delay of less than 1 ms occurs considering the distance to a base station of up to about 100 km, but in a satellite network, the distance to a satellite may be thousands of km, and the distance from the satellite to the base station may also be thousands of km. Because of this, the delay time can occur much larger than that of the terrestrial network. 31 is a diagram showing an example of a difference in propagation delay time between a terrestrial network and a satellite network. In satellite network communication, the delay time varies according to the altitude and altitude angle of the satellite. In FIG. 31, the terminal-satellite distance according to the altitude angle when the satellite altitude is 700 km and the time required for radio waves to travel back and forth are shown. In the case of the satellite network, a low-orbit satellite is assumed, and when the elevation angle is 0 to 180 °, the radio round trip time (radio RTT, which includes the round-trip time required for the signal to be transmitted between the transmitter and receiver and the processing time at the counterpart node) It is shown that) can occur from 40.9 ms to 9.3 ms. The delay time is just an example and may vary depending on the altitude and orbit of the satellite, and for example, when the altitude is high, the delay time may increase on average.

Since the maximum delay time is within 1 or 2 ms in the terrestrial network, the timing advance provided by the LTE and 5G NR systems allows the base station to match the slot timing for transmitting the downlink with the slot timing for receiving the uplink. (That is, indexes of DL slots and UL slots may match). That is, if the terminal performs uplink transmission ahead of the downlink timing by the timing advance value indicated by the base station, when the uplink signal transmitted by the terminal is received by the base station, it coincides with the downlink timing of the base station. On the other hand, in a satellite network, it is impossible to match slot timing for transmitting downlink and slot timing for receiving uplink from the station's point of view through timing advance provided by conventional LTE and 5G NR systems. This is because the propagation delay time generated in the satellite network is as large as several tens of ms, and this propagation delay time is greater than the maximum value of timing advance provided by the conventional LTE and 5G NR systems.

The satellite navigation system may also be referred to as a Global Navigation Satellite System (GNSS), and the GNSS may include, for example, GPS of the United States, GLONASS of Russia, Galileo of the EU, Beidou of China, and the like. The GNSS may include a Regional Navigation Satellite System (RNSS), and the RNSS may include, for example, India's IRNSS, Japan's QZSS, and Korea's KPS. Meanwhile, the signal transmitted from the GNSS may include at least one of auxiliary navigation information, satellite normal operation state, satellite time, satellite ephemeris, satellite altitude, reference time, and information on various correction data.

Meanwhile, in various embodiments of the present disclosure, an NTN satellite may be a communication satellite serving to transmit a signal for a terminal to connect to a base station. Also, in various embodiments of the present disclosure, a GNSS satellite may be a satellite that transmits a signal of a satellite navigation system. Meanwhile, the terminal may receive a signal from each of one or more GNSS satellites, calculate the position of the terminal itself based on the signal received from each of the one or more GNSS satellites, and furthermore, the one or more GNSS satellites A reference time at each of the GNSS satellites may be identified. If the terminal can calculate a plurality of positions of the terminal based on signals received from a plurality of GNSS satellites, the terminal has the average of the plurality of positions or the strongest intensity among the plurality of positions Based on the position corresponding to the received signal or the average value of the plurality of positions based on the signal strength (for example, a method of applying a weight to a position corresponding to a signal having a high signal strength), the actual position of the terminal itself is determined. can be calculated Here, a method for calculating the location of the terminal itself based on signals received by the terminal from the plurality of GNSS satellites may be implemented in various forms, and a detailed description thereof will be omitted.

In various embodiments of the present disclosure, the time obtained from GNSS or the time of the base station transmitted by the base station may be based on coordinated universal time (UTC) time, which is based on the Gregorian calendar. It may be based on the time from January 1, 1900 00:00:00 of the calendar). This may vary depending on the type of GNSS system, and a reference time zone as shown in Table 23 below may be used.

[Table 23]

In Table 23, NavIC means NAVigation with Indian Constellation, QZS is Quasi Zenith Satellite, QZSS is Quasi-Zenith Satellite System, QZST is Quasi-Zenith System Time, SBAS is Space Based Augmentation System, and BDS is BeiDou Navigation Satellite System. it could mean

In addition, the base station may indicate the type of a GNSS system that is used as a reference for position or time information used by the base station itself through a satellite, and an indicator shown in Table 24 below may be used.

[Table 24]

As described above, the terminal can calculate the time required for a signal to be transmitted from the NTN satellite to the terminal based on the position of the terminal itself calculated by the terminal itself and the position of the NTN satellite received from the NTN satellite, Based on this, a TA value can be determined. When the terminal determines the TA value, the distance from the NTN satellite to the terrestrial base station or, when the corresponding signal is transmitted to the terrestrial base station via another NTN satellite, the distance from the NTN satellite to another NTN satellite can be considered

Alternatively, the terminal may obtain reference time information from information transmitted by GNSS satellites, compare the time information transmitted by NTN satellites with the reference time information obtained from the GNSS satellites, and compare the result It is possible to calculate the time (propagation delay) required from the NTN satellite to the terminal based on .

Location and time information of the NTN satellite may be transmitted from the base station to the terminal through the SIB. This may be directly transmitted by the NTN satellite.

(단위 km)라하고, 빛의 속도를

(단위 km/sec)라 할 때,

는

(단위 sec)에 기반하여 결정될 수 있다. 예를 들어,

로 결정되어 적용될 수 있으며, 이는

값을 정수화 하여

로 결정할 수 있는 방법이다. 또는/및 추가적으로는 하기와 같은 방법으로 결정하고

의 정보를 기지국으로 보고할 수 있을 것이다. The distance between the terminal and the satellite or a value corresponding to it

(unit km), and the speed of light

(unit km/sec)

Is

(unit sec). for example,

can be determined and applied as

by purifying the value

way that can be determined. or/and additionally determined in the following manner

Information of may be reported to the base station.

로 정하고, D는 정수이며, a는 0보다 크거나 같고 1보다 작은 소수이다. 여기서

이고,

이다. 즉 이 방법은 단말과 위성 사이의 propagation delay를 정수와 소수 부분으로 나누어, 상기 정수 또는 그에 대응되는 값만 보고 하거나, 상기 정수 및 소수 또는 그에 대응되는 값들을 각각 보고하는 방법일 수 있다. 이를 이용하여 propagation delay를 보고하기 위해 보고해야하는 비트 수를 줄일 수 있다. 여기에서 소수부분은 상기에서는

의 정수배가 되도록 설명하였지만,

의 배수가 되도록 결정될 수 있을 것이다. 상기에서

는 현재 캐리어 또는 BWP, 또는 관련된 CORESET의 부반송파간격을 의미할 수 있다. 또는 송수신하는 PDSCH나 PUSCH 등 송수신 신호에 사용되는 값일 수 있다. 여기에서

는 각각 부반송파 간격 15 kHz, 30 kHz, 60 kHz, 120 kHz, 240 kHz, 480 kHz에 대응되는 값일 수 있다. 또는

는

의 결정을 위해 기지국으로부터 상위 시그널링을 통해 설정될 수 있다. 또는

는 고정된 값으로 사용될 수 있으며, 일례로

처럼

값 중에 하나로 고정되어 사용될 수 있다. - Method A1:

, D is an integer, and a is a prime number greater than or equal to 0 and less than 1. here

ego,

to be. That is, this method may be a method of dividing the propagation delay between the terminal and the satellite into integer and fractional parts and reporting only the integer or values corresponding thereto, or reporting the integers and decimals or values corresponding thereto, respectively. By using this, it is possible to reduce the number of bits to be reported in order to report the propagation delay. Here, the fractional part is

It was explained to be an integer multiple of

It can be determined to be a multiple of from above

may mean the current carrier or BWP, or the subcarrier spacing of the related CORESET. Alternatively, it may be a value used for a transmission/reception signal such as a PDSCH or a PUSCH to be transmitted/received. From here

may be values corresponding to subcarrier spacings of 15 kHz, 30 kHz, 60 kHz, 120 kHz, 240 kHz, and 480 kHz, respectively. or

Is

It may be set through upper signaling from the base station for the determination of. or

can be used as a fixed value, for example

like

It can be fixed and used as one of the values.

가

의 배수가 되도록 결정될 수 있을 것이다. 이는

와 같이 결정될 수 있다. 본 발명에서

는 x보다 크지 않은 최대 정수를 의미할 수 있으며, 이는 숫자를 정수단위에서 내림 하는 즉 소수 값을 버리는 것일 수 있다. 본 방법에서

를 사용한 내림 대신에, 소수자리에서 올림이나 반올림을 대신 사용할 수 있을 것이다. 상기에서

는 현재 캐리어 또는 BWP, SIB, 또는 관련된 CORESET의 부반송파간격을 의미할 수 있다. 또는 송수신하는 PDSCH나 PUSCH 등 송수신 신호에 사용되는 값일 수 있다. 여기에서

는 각각 부반송파 간격 15 kHz, 30 kHz, 60 kHz, 120 kHz, 240 kHz, 480 kHz에 대응되는 값일 수 있다. 또는

는

의 결정을 위해 기지국으로부터 상위 시그널링을 통해 설정될 수 있다. 또는

는 고정된 값으로 사용될 수 있으며, 일례로

로 고정되어 사용될 수 있다. 또는 상기

계산에 사용될

는 기지국이 별도로 SIB나 상위 시그널링을 통해 설정해줄 수 있을 것이다. - Method A2:

go

It can be determined to be a multiple of this is

can be determined as in the present invention

may mean the largest integer not greater than x, which may be rounding the number down from an integer unit, that is, discarding a decimal value. in this method

Instead of rounding down using , rounding up or rounding to decimal places could be used instead. from above

may mean the subcarrier spacing of the current carrier or BWP, SIB, or related CORESET. Alternatively, it may be a value used for a transmission/reception signal such as a PDSCH or a PUSCH to be transmitted/received. From here

may be values corresponding to subcarrier spacings of 15 kHz, 30 kHz, 60 kHz, 120 kHz, 240 kHz, and 480 kHz, respectively. or

Is

It may be set through upper signaling from the base station for the determination of. or

can be used as a fixed value, for example

can be fixed and used. or above

to be used in the calculation

may be separately set by the base station through SIB or higher signaling.

으로 정하고, 상기에서

는

가

와 가장 가까워지도록 하는 정수로 정할 수 있다. 혹은,

를 만족하도록 하는 최소 정수로 정할 수 있거나,

를 만족하도록 하는 최대 정수로 정할 수 있다. - Method A3:

, and in the above

Is

go

It can be set as an integer that is closest to . or,

It can be set to the minimum integer that satisfies

It can be set as the largest integer that satisfies .

으로 정할 수 있다. 이것은 단말과 위성 사이의 링크(서비스 링크라 부를 수 있다)에서 발생하는 propagation delay가 상기 위성의 특정 빔내의 커버리지 안의 단말들이 거의 차이가 없으므로, 종래의 TA 메커니즘과

으로 상향링크 시간 동기화를 이룰 수 있기 때문일 수 있다. 단말이

값을

으로 설정할지, 또는 GNSS 신호에 따라 위성과 단말의 위치 및 빛의 속도에 기반하여 계산한

값을 사용할지를 기지국은 SIB를 통해 설정할 수 있다. 또 다른 일례로는, 단말이 GNSS 신호에 따라 위성과 단말의 위치 및 빛의 속도에 기반하여 PRACH preamble을 전송하는 시점을 기준으로 계산한

값을 별도의 지시나 설정이 있을 때까지 계속 사용할지, 또는 상향링크 전송시점마다 새로이 계산한

값을 사용할지를 기지국이 SIB나 별도의 RRC 시그널링으로 설정할 수 있다. 즉, 이는 상기 수학식 5에서, 하기와 같이

값을 정하는 것일 수 있다. - Method A4: according to base station settings

can be set as This is different from the conventional TA mechanism because the propagation delay occurring in the link between the terminal and the satellite (which can be called a service link) is almost the same between terminals within coverage within a specific beam of the satellite.

This may be because uplink time synchronization can be achieved with . Terminal

value

, or calculated based on the location of satellites and terminals and the speed of light according to GNSS signals.

The base station can set whether to use the value through the SIB. In another example, based on the time point at which the UE transmits the PRACH preamble based on the location of the satellite and the UE and the speed of light according to the GNSS signal,

Whether to continue using the value until there is a separate instruction or setting, or a newly calculated value at each uplink transmission

The base station can set whether to use the value through SIB or separate RRC signaling. That is, in Equation 5 above, as follows

It may be to set a value.

is UE self-estimated TA to pre-compensate for the service link delay if configured, and

is 0 otherwise.

is UE self-estimated TA to pre-compensate for the service link delay if configured, and

is 0 otherwise.

를 결정하는 방법들은 일례일 뿐이며 보다 다양한 방법이 존재할 수 있다. 예를 들어, 일반적으로

값을 정수로 정의하거나 정수 값에 기반한 표현을 정의할 경우에 특정 정수(integer) 또는 유리수(rational number) 값

의 배수로 나타내기 위해서

또는

등과 같이 표현할 수도 있다. 여기서

는 사전에 결정된 값일 수도 있으며, 시그널링 파라미터들의 의해 결정되는 값일 수도 있다. 방법2는

인 경우를 의미하며 이와 같이,

는

또는

같은 시스템 파라미터 중 적어도 하나에 따라 결정될 수도 있다. 이와 같은 방식은

값들에 대한 입도(granularity, 粒度)가 다소 성긴(sparse) 특징을 갖는 대신에 동일한 비트의 시그널링을 보다 다양한 값들을 표현할 수 있는 장점이 있다. 또한, 상기 각 방법에서

와 같은 사용한 내림 연산 대신에, 소수자리에서 올림(

)이나 반올림

연산 등에 기반하여 그 값들을 결정할 수도 있다.In methods A1 to A4, based on the distance between the terminal and the satellite (or a value corresponding thereto) and the speed of light

The methods for determining are only one example, and more diverse methods may exist. For example, usually

A specific integer or rational number value when defining a value as an integer or defining an expression based on an integer value.

to express as a multiple of

or

It can also be expressed as here

may be a predetermined value or may be a value determined by signaling parameters. Method 2 is

, and as such,

Is

or

It may be determined according to at least one of the same system parameters. A method like this

Instead of having somewhat sparse granularity of values, there is an advantage in that signaling of the same bit can express more diverse values. In addition, in each of the above methods

Instead of using a rounding operation like

) or round

The values may be determined based on calculations or the like.

[Fourth Embodiment]

를 기지국이 단말에게 전달하고, 단말이 계산 및 적용하는 방법을 제공한다. In the fourth embodiment, the first and second embodiments have been described.

The base station delivers to the terminal, and the terminal provides a method for calculating and applying.

정보를 기지국이 단말에게 전달하는 방법이며, 이 중 적어도 하나 또는 하나 이상의 방법이 결합되어 적용될 수 있다. In the following, the base station sets and instructs the terminal to

This is a method of transmitting information from a base station to a terminal, and at least one of these methods or a combination of one or more methods may be applied.

라고 하고, 이를 기반하여

가 결정될 수 있다.- Method B1: The base station may set one offset value to the terminal through RRC signaling. This set value is

and, based on this

can be determined.

라고 하고, 이를 기반하여

가 결정될 수 있다. 이 방법은 상기 방법 B1을 사용하는 경우에 비해 기지국과 단말이 N_TA,common을 적용하는 시점을 기지국과 단말 서로가 명확히 할 수 있는 장점이 있다. 일례로 상기 MAC CE 의 수신 시점 또는 상기 MAC CE의 수신에 대한 ACK을 송신한 시점을 기준으로 일정 시간 후부터 N_TA,common이 적용될 수 있다. 일례로, 기지국은 MAC CE 8비트를 통해 msec 단위로

를 전달하여 0ms 부터 255ms 까지 전달할 수 있을 것이다. 이 때

는

와 같이 결정된다. - Method B2: The base station may indicate one offset value to the terminal through the MAC CE. This set value is

and, based on this

can be determined. Compared to the case of using the method B1, this method has an advantage in that the base station and the user equipment can clarify when the base station and the user equipment apply N _TA,common . For example, N _TA,common may be applied after a certain time based on the MAC CE reception time or the time when the ACK for the MAC CE reception is transmitted. As an example, the base station in msec units through MAC CE 8 bits

You can pass it from 0ms to 255ms. At this time

Is

is determined as

의 후보값들이 되고, 기지국은 이 중 하나를 MAC CE를 통해 지시해줄 수 있다. - Method B3: The base station may set one or more offset values to the terminal through higher layer signaling. Alternatively, these values may be preset. This set value is

Become candidate values of , and the base station can indicate one of them through the MAC CE.

라고 하고, 이를 기반으로

가 결정될 수 있다. 이 값을 이용하여 단말은 초기 접속 과정에서 PRACH preamble을 전송할 때 TA를 계산해 적용된다. 이후에는, MAC CE를 통해

가 단말에게 지시되고, 단말은 이를 이용해

의 변화량을 계산할 수 있으며,

와 같이 계산될 수 있다. 상기에서 x와 y는

의 전달을 위한 비트 수 및 단위에 따라 결정될 수 있다. 예를 들어,

와 같이 결정될 수 있다. 여기서

값은 31일 수도 있으며, MAC CE를 통해 지시될 수 있는

값의 최댓값이 63 보다 큰 경우에는 31 보다 크거나 같은 값일 수도 있으며,

값의 최댓값이 63 보다 작은 경우에는 31 보다 작거나 같은 값일 수도 있다.- Method B4: The base station may set one offset value to the terminal through the SIB. This set value is

and, based on this

can be determined. Using this value, the UE calculates and applies the TA when transmitting the PRACH preamble in the initial access process. Afterwards, via MAC CE

is instructed to the terminal, and the terminal uses it

The change in can be calculated,

can be calculated as In the above, x and y are

It may be determined according to the number of bits and units for transmission of . for example,

can be determined as here

The value may be 31, which may be indicated through the MAC CE.

If the maximum value of the value is greater than 63, it may be greater than or equal to 31,

If the maximum value is less than 63, it may be less than or equal to 31.

라고 하고, 이를 기반하여

가 결정될 수 있다. 이 방법은 상기 방법B1보다 기지국과 단말 사이의 N_TA,common의 적용 시점을 명확히 할 수 있는 장점이 있다. 일례로 상기 MAC CE 의 수신 시점 또는 상기 MAC CE의 수신에 대한 ACK을 송신한 시점을 기준으로 일정 시간 후부터 N_TA,common이 적용될 수 있다. 일례로, 기지국은 MAC CE 약 19비트 또는 24비트를 통해

sec 단위의

를 전달할 수 있을 것이다. 이 때

는

와 같이 결정된다. MAC CE의 비트 수는 상기 일례 뿐만이 아니라 다른 수가 적용될 수도 있다. - Method B5: The base station may indicate one offset value to the terminal through the MAC CE. This set value is

and, based on this

can be determined. This method has the advantage of being able to clarify the application time point of N _TA,common between the base station and the terminal compared to the above method B1. For example, N _TA,common may be applied after a certain time based on the MAC CE reception time or the time when the ACK for the MAC CE reception is transmitted. As an example, the base station via the MAC CE about 19 bits or 24 bits

in sec units

will be able to deliver At this time

Is

is determined as The number of bits of the MAC CE may be applied in addition to the above example.

라고 하고, 이와 함께 위성의 고도에 기반하여

가 결정될 수 있다. 이 방법은 상기 방법 B5를 이용하는 경우에 비해 전달되어야 하는 비트 수를 줄일 수 있는 장점이 있다. 일례로, 기지국은 MAC CE 약 16비트를 통해

sec 단위의

를 전달할 수 있을 것이다. 이 때

는

와 같이 결정된다. 상기에서

는 위성의 고도이다. 이는 위성이 특정 고도에 있는 경우, 단말과 위성 사이의 최소 거리는 상기 특정 고도가 되므로, 기지국이 나머지 추가 거리만

를 통해 시그널링하는 의미일 수 있다. MAC CE의 비트 수는 상기 일례 뿐만이 아니라 다른 수가 적용될 수도 있다. 상기 수식에서

값은 실시예 3과 비슷한 방법을 통해 정수화 또는 유리수화 하여 정의될 수도 있다. 예를 들어,

또는

또는

등과 같이 내림 연산을 이용한 정수화 또는 유리수화 뿐만 아니라 실시예 3에서

값 대신

값을 기반으로 다양한 정수화 또는 유리수화 방식이 적용 가능하다. 물론

값 전체에 대해 상기 설명과 비슷한 정수화 또는 유리수화를 적용할 수도 있다. 예를 들어,

와 같이 정의할 수도 있으며, 이 경우는

에서

로 간주한 것고 동일한 방식이다. 또한 상기 정수화 또는 유리수화를 위해 사용된 연산은 내림 뿐만 아니라 올림, 반올림 등 다양한 다른 연산을 적용할 수도 있다. - Method B6: The base station may indicate one offset value to the terminal through the MAC CE. This set value is

and based on the altitude of the satellite

can be determined. This method has the advantage of reducing the number of bits to be transmitted compared to the case of using method B5. As an example, the base station via the MAC CE about 16 bits

in sec units

will be able to deliver At this time

Is

is determined as from above

is the altitude of the satellite. This is because when the satellite is at a specific altitude, the minimum distance between the terminal and the satellite is the specific altitude, so the base station is only the remaining additional distance.

It may mean signaling through. The number of bits of the MAC CE may be applied in addition to the above example. in the above formula

The value may be defined by integerization or rationalization through a method similar to Example 3. for example,

or

or

In Example 3, as well as integerization or rationalization using rounding operations, such as

instead of value

Based on the value, various integer or rational hydration methods can be applied. of course

It is also possible to apply integerization or rationalization similar to the above description to the entire value. for example,

It can also be defined as, in this case

at

is regarded as the same method. In addition, various other operations such as rounding up and rounding in addition to rounding down may be applied to the operation used for integerization or rationalization.

값과

의 변화율 정보를 전달할 수 있다. 상기 정보들은 SIB가 아니라 특정 단말에게 RRC 시그널링을 통해 전달될 수 있을 것이며, 단말의 상태(RRC_idle, RRC_inactive, RRC_connected)에 따라 전달방법이 달라질 수 있다.

의 변화율 정보는 하나 또는 두개 또는 3개의 파라미터를 통해 SIB를 통해 전달될 수 있을 것이다. 일례로, 하나의 파라미터

로 변화율 정보가 전달된다면, SIB로

가 전달된 시점을 t1이라 하고, t2가 상향링크 전송이 수행되는 시점이라고 할 때, t2에서 단말이 적용할

인

는

와 같이 계산될 수 있다. 이 때, t1와 t2의 단위는 msec이고 A의 단위는 Tc/msec 일 수 있다. 즉, A가 의미하는 것은, 1 msec당 몇 개의 Tc만큼

값이 변화했는지를 가리킬 수 있다. 또 다른 일례로, 두개의 파라미터

와

로 변화율 정보가 전달된다면, SIB로

가 전달된 시점을 t1이라 하고, t2가 상향링크 전송이 수행되는 시점이라고 할 때, t2에서 단말이 적용할

인

는

와 같이 계산될 수 있다. (n개의 파라미터를 통해 변화율 정보가 전달된 경우에는 두 시점의 차이

에 대한 n차 다항식 형태로 표현하는 것도 가능하다.) 이 때, t1와 t2의 단위는 msec이고 A의 단위는 Tc/msec이며, B의 단위는 Tc/msec^2 일 수 있다. 즉, A가 의미하는 것은, 1 msec당 몇 개의 Tc만큼

값이 변화했는지, B이 의미하는 것은, 1 msec당 몇 개의 Tc만큼

값의 변화율이 변화했는지를 가리킬 수 있다.-Method B7: The base station receives the information through the SIB

value and

of change rate information can be transmitted. The above information may be delivered to a specific terminal through RRC signaling rather than to the SIB, and the delivery method may vary depending on the status of the terminal (RRC_idle, RRC_inactive, RRC_connected).

The change rate information of may be transmitted through the SIB through one, two, or three parameters. As an example, one parameter

If rate-of-change information is transmitted to SIB,

Assuming that the transmitted time is t1 and t2 is the time at which uplink transmission is performed, the UE applies at t2.

sign

Is

can be calculated as At this time, the units of t1 and t2 may be msec, and the unit of A may be Tc/msec. That is, what A means is how many Tc per 1 msec.

It can indicate whether the value has changed. As another example, two parameters

Wow

If rate-of-change information is transmitted to SIB,

Assuming that the transmitted time is t1 and t2 is the time at which uplink transmission is performed, the UE applies at t2.

sign

Is

can be calculated as (The difference between two points in time when change rate information is transmitted through n parameters

It is also possible to express it in the form of an nth-order polynomial for .) At this time, the units of t1 and t2 may be msec, the unit of A may be Tc/msec, and the unit of B may be Tc/msec^2. That is, what A means is how many Tc per 1 msec.

Whether the value has changed, what B means, by how many Tc per 1 msec

It can indicate whether the rate of change of the value has changed.

[Fifth Embodiment]

A fifth embodiment provides a method and apparatus for a base station to transmit K_offset (K _offset ), a parameter for determining timing at which a terminal transmits a second signal with respect to a first signal transmitted by a base station, to a terminal.

While transmitting the first signal, the base station indicates a time point when the terminal transmits the second signal corresponding to the first signal using upper signaling and DCI. For example, while transmitting the PDSCH, HARQ-ACK feedback for this may be indicated by an HARQ-ACK timing related indicator of a bit field of a DCI that schedules the PDSCH. However, in satellite communication, since the delay time between the terminal and the base station is very large, correct timing may not be indicated with the offset value indicated by the conventional DCI. Therefore, the base station transmits the K_offset value, which is an additional timing offset, to the terminal through the SIB, and the terminal can determine the transmission timing of the second signal (uplink transmission) by adding the offset K_offset. In the RRC_connected state after the terminal accesses the terminal, the base station may update the K_offset value to the terminal through RRC signaling. However, when updating is performed only through RRC signaling, the base station and the terminal may have different K_offsets during the time interval in which RRC reconfiguration is performed. In this case, correct transmission and reception of the second signal may not be performed. In order to eliminate this ambiguity time interval, the base station may set a plurality of K_offset values to the terminal and indicate one of the set K_offset values to the MAC CE. Accordingly, the terminal may apply the updated K_offset value from a predetermined point in time after receiving the MAC CE.

For example, candidate values of the K_offset value may be set according to the index as shown in Table 25 through RRC signaling.

[Table 25]

와 같이

(M은 2, 3, 4, … 와 같은 정수)개로 이루어져 있으며, 인덱스 i인 경우의 K_offset 값을 K_offset(i)라 할 때, i > 0에 대해 K_offset(i) = K_offset(0) + (i - 1)*A (A는 양수인 상수)와 같이 균일한 간격의 값들을 갖도록 정의될 수도 있다. 물론 시스템 설정에 따라 M 값은 가변일 수도 있으며, M 값에 따라 A 값 또한 가변적으로 설정될 수 있다. 또한 인덱스 중의 일부는 reserved field로 정의될 수도 있다. reserved field를 제외한 K_offset의 최댓값이 K_offset(i_max)라 할 때, A = (K_offset(i_max) - K_offset(0))/i_max의 관계가 있을 수 있다. [Table 25] is an example of setting K_offset at regular intervals through 8 indices, and various other settings are possible. If the values of index i are 0, 1, 2, ... ,

together with

(M is an integer such as 2, 3, 4, …), and when the K_offset value in case of index i is K_offset(i), for i > 0 K_offset(i) = K_offset(0) + ( It can also be defined to have uniformly spaced values, such as i - 1)*A (where A is a positive constant). Of course, the M value may be variable according to system settings, and the A value may also be variably set according to the M value. Also, some of the indexes may be defined as reserved fields. When the maximum value of K_offset excluding the reserved field is K_offset(i_max), there may be a relationship of A = (K_offset(i_max) - K_offset(0))/i_max.

로 설정될 수도 있으며, 일반적으로 다른 정수 값으로 설정될 수도 있다.)Of course, this is only an example of setting values of uniform difference, and generally may not consist of values of uniform difference as a whole. For example, it may be set to different difference values according to the range of the index as follows. (i_m value is simply

It can also be set to , and generally can be set to other integer values.)

1 ≤ i < i_m,

K_offset(i) = K_offset(0) + (i - 1)*A1

i_m ≤ i ≤ i_max,

K_offset(i) = K_offset(i_m) + (i - i_m)*A2

A1, A2 are different constants that are positive, A1 = (K_offset(i_m-1) - K_offset(0))/(i_m-1), A2 = (K_offset(i_max) - K_offset(i_m))/(i_max - i_m) ),

Thereafter, the base station transmits the index to the terminal through the MAC CE in slot n, and the terminal may transmit the second signal by applying the indicated K_offset in slot n+k. In the above, the k value may be set or may be determined according to the subcarrier interval.

Although the first to fifth embodiments of the present invention have been described above for convenience of explanation, since each embodiment includes operations related to each other, it is also possible to configure a configuration by combining at least two or more embodiments. In addition, the methods of each embodiment are not mutually exclusive, and it is possible to perform a combination of one or more methods.

A method for transmitting and receiving a base station, a satellite, and a terminal or a transmitting end and a receiving end for performing the above embodiments of the present invention is shown, and in order to perform this, the base station, satellite, and receiving unit, processing unit, and transmitting unit of the terminal respectively operate according to the embodiment. shall.

Specifically, FIG. 32 is a block diagram showing the internal structure of a terminal according to an embodiment of the present invention. As shown in FIG. 32 , the terminal of the present invention may include a terminal receiving unit 3200, a terminal transmitting unit 3220, and a terminal processing unit 3210. The terminal receiver 3200 and the terminal transmitter 3220 may collectively be referred to as transceivers in an embodiment of the present invention. The transmitting/receiving unit may transmit/receive signals with the base station. The signal may include control information and data. To this end, the transceiver may include an RF transmitter for up-converting and amplifying the frequency of a transmitted signal, and an RF receiver for low-noise amplifying a received signal and down-converting its frequency. In addition, the transmitting/receiving unit may receive a signal through a wireless channel, output the signal to the terminal processing unit 3210, and transmit the signal output from the terminal processing unit 3210 through the wireless channel. The terminal processing unit 3210 may control a series of processes so that the terminal can operate according to the above-described embodiment of the present invention. For example, the terminal receiving unit 3200 may receive a signal from a satellite or terrestrial base station and a signal from a GNSS, and the terminal processing unit 3210 may transmit and receive signals to and from the base station according to the method described in the present invention. Thereafter, the terminal transmitter 3220 may transmit a signal using the determined time point.

33 is a block diagram showing the internal structure of a satellite according to an embodiment of the present invention. As shown in FIG. 33, the satellite of the present invention may include a satellite receiving unit 3300, a satellite transmitting unit 3320, and a satellite processing unit 3310. In the above, the receiving unit, the transmitting unit, and the processing unit may be configured in plurality. That is, it may be composed of a receiver and transmitter for transmitting and receiving signals from the terminal, and a receiver and transmitter for transmitting and receiving signals from the base station (and a receiver and transmitter for transmitting and receiving signals to and from other satellites). The satellite receiving unit 3300 and the satellite transmitting unit 3320 may collectively be referred to as satellite transceivers in an embodiment of the present invention. The transmitting/receiving unit may transmit/receive signals between the terminal and the base station. The signal may include control information and data. To this end, the transceiver may include an RF transmitter for up-converting and amplifying the frequency of a transmitted signal, and an RF receiver for low-noise amplifying a received signal and down-converting its frequency. In addition, the transmitting/receiving unit may receive a signal through a wireless channel, output the signal to the satellite processing unit 3310, and transmit the signal output from the satellite processing unit 3310 through a wireless channel. The satellite processing unit 3310 may include a compensator (pre-compensator) for correcting a frequency offset or a Doppler shift, and may include a device capable of tracking a position from a GPS or the like. In addition, the satellite processing unit 3310 may include a frequency shift function capable of shifting the center frequency of the received signal. The satellite processing unit 3310 may control a series of processes so that the satellite, the base station, and the terminal may operate according to the above-described embodiment of the present invention. For example, the satellite receiving unit 3300 may receive a PRACH preamble from the terminal and transmit TA information to the base station while transmitting RAR according to the PRACH preamble to the terminal again. Thereafter, the satellite transmission unit 3320 may transmit corresponding signals at the determined time point.

34 is a block diagram showing the internal structure of a base station according to an embodiment of the present invention. As shown in FIG. 34, the base station of the present invention may include a base station receiving unit 3400, a base station transmitting unit 3420, and a base station processing unit 3410. The base station may be a terrestrial base station or may be part of a satellite. The base station receiving unit 3400 and the base station transmitting unit 3420 may collectively be referred to as transceivers in an embodiment of the present invention. The transmission/reception unit may transmit/receive signals with the terminal. The signal may include control information and data. To this end, the transceiver may include an RF transmitter for up-converting and amplifying the frequency of a transmitted signal, and an RF receiver for low-noise amplifying a received signal and down-converting its frequency. In addition, the transceiver may receive a signal through a radio channel, output the signal to the base station processor 3410, and transmit the signal output from the base station processor 3410 through a radio channel. The base station processing unit 3410 may control a series of processes so that the base station operates according to the above-described embodiment of the present invention. For example, the base station processing unit 3410 may transmit RAR including TA information.

On the other hand, the embodiments of the present invention disclosed in the present specification and drawings are only presented as specific examples to easily explain the technical content of the present invention and help understanding of the present invention, and are not intended to limit the scope of the present invention. That is, it is obvious to those skilled in the art that other modifications based on the technical idea of the present invention can be implemented. In addition, each of the above embodiments can be operated in combination with each other as needed. In addition, the above embodiments will be able to implement other modifications based on the technical idea of the above embodiments, such as an LTE system and a 5G system.

Claims (1)

In the method of processing a control signal of a terminal in a wireless communication system,
Receiving a first control signal transmitted from a base station; processing the received first control signal; and transmitting a second control signal generated based on the processing to the base station.

Images