阅读说明：本技术 无线通信系统中分配发送功率的方法和装置 (Method and apparatus for allocating transmission power in wireless communication system ) 是由 柳贤锡 吕贞镐 吴振荣 朴成珍 方钟弦 申哲圭 于 2020-01-07 设计创作，主要内容包括：本公开涉及一种用于将IoT技术与支持比4G系统更高的数据传输速率的5G通信系统相融合的通信技术及其系统。本公开可应用于基于5G通信技术和IoT相关技术的智能服务,例如智能家居、智能建筑、智能城市、智能汽车、车联网、医疗保健、数字教育、智能零售、安保和安全服务。本公开提供了一种在无线通信系统中分配发送功率的方法和装置。(The present disclosure relates to a communication technology for merging an IoT technology with a 5G communication system supporting a higher data transmission rate than a 4G system, and a system thereof. The present disclosure is applicable to smart services based on 5G communication technologies and IoT related technologies, such as smart homes, smart buildings, smart cities, smart cars, car networking, healthcare, digital education, smart retail, security, and security services. The present disclosure provides a method and apparatus for allocating transmission power in a wireless communication system.)

1. A method of a User Equipment (UE) in a wireless communication system, the method comprising:

detecting a first side link transmission using a first Radio Access Technology (RAT) and a second side link transmission using a second RAT;

determining whether the first sidelink transmission and the second sidelink transmission overlap;

determining a sidelink to transmit if the first sidelink transmission and the second sidelink transmission overlap; and

and transmitting side link information in the determined side link.

2. The method of claim 1, wherein determining the side link comprises: determining the sidelink based on priority information included in Sidelink Control Information (SCI).

3. The method of claim 2, wherein transmitting the sidelink information comprises: and sending the side link information with high priority included in the priority information.

4. The method of claim 1, wherein the first RAT is fourth generation (4G) and the second RAT is fifth generation (5G).

5. The method of claim 1, wherein determining the side link comprises: determining the sidelink based on priority information indicated by a higher layer if the first sidelink transmission and the second sidelink transmission overlap.

6. The method of claim 5, wherein transmitting the sidelink information comprises: and transmitting the sidelink synchronization signal with high priority included in the priority information.

7. The method of claim 1, wherein transmitting the sidelink information comprises:

the sidelink is determined based on priority information predetermined according to the type of the physical layer channel, and a high-priority sidelink is transmitted.

8. The method of claim 1, wherein the first sidelink transmission using the first RAT and the second sidelink transmission using the second RAT are determined based on a capability of the UE.

9. A UE, the UE comprising:

a transceiver capable of transmitting and receiving at least one signal; and

a controller coupled to the transceiver and configured to control the transceiver,

wherein the controller is configured to:

detecting a first side link transmission using a first Radio Access Technology (RAT) and a second side link transmission using a second RAT;

determining whether the first sidelink transmission and the second sidelink transmission overlap;

determining a sidelink to transmit if the first sidelink transmission and the second sidelink transmission overlap; and

and transmitting side link information in the determined side link.

10. The UE of claim 9, wherein the controller is configured to: determining the sidelink based on priority information included in Sidelink Control Information (SCI).

11. The UE of claim 10, wherein the controller is configured to: and sending the side link information with high priority included in the priority information.

12. The UE of claim 9, wherein the first RAT is fourth generation (4G) and the second RAT is fifth generation (5G).

13. The UE of claim 9, wherein, in the case that the first sidelink transmission and the second sidelink transmission overlap, the controller is configured to: and determining the sidelink based on priority information indicated by a high layer, and transmitting a sidelink synchronization signal with high priority included in the priority information.

14. The UE of claim 9, wherein the controller is configured to: the sidelink is determined based on priority information predetermined according to a type of a physical layer channel, and a high-priority sidelink is transmitted.

15. The UE of claim 9, wherein the first sidelink transmission using the first RAT and the second sidelink transmission using the second RAT are determined based on a capability of the UE.

Technical Field

The present disclosure relates to a method of distributing and allocating transmission power in a wireless communication system, and more particularly, to a method and apparatus for a new air interface (NR) vehicle-to-outside (V2X) UE, which can communicate through one or more of an NR uplink, a Long Term Evolution (LTE) uplink, an NR side link, and an LTE side link to distribute and allocate transmission power.

Background

Since the deployment of 4G communication systems, there has been an effort to develop an improved 5G or pre-5G communication system in order to meet the demand for wireless data traffic. Accordingly, the 5G or pre-5G communication system is also referred to as an "beyond 4G network" or a "post-LTE system".

5G communication systems are known to be implemented in the higher frequency (mmWave) band, e.g., the 60GHz band, in order to achieve higher data rates. In order to reduce propagation loss of radio waves and increase transmission distance, beamforming, massive Multiple Input Multiple Output (MIMO), full-dimensional MIMO (FD-MIMO), array antenna, analog beamforming, massive antenna techniques are discussed in the 5G communication system.

In addition, in the 5G communication system, development of system network improvement is being performed based on advanced small cells, cloud Radio Access Networks (RANs), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, mobile networks, cooperative communication, coordinated multipoint (CoMP), receiver interference cancellation, and the like.

In 5G systems, hybrid FSK and QAM modulation (FQAM) and Sliding Window Superposition Coding (SWSC) have been developed as Advanced Coding Modulation (ACM), and filter bank multi-carrier (FBMC), non-orthogonal multiple access (NOMA), and Sparse Code Multiple Access (SCMA) have been developed as advanced access techniques.

The internet is a human-centric connection network in which humans produce and consume information, and is now evolving towards the internet of things (IoT), where distributed entities (e.g., things) exchange and process information without human intervention. Internet of everything (IoE) has emerged, which is formed by IoT technology and big data processing technology through connection with a cloud server. With the demand of technical elements such as "sensing technology", "wired/wireless communication and network infrastructure", "service interface technology", and "security technology" in IoT implementation, sensor networks, machine-to-machine (M2M) communication, Machine Type Communication (MTC), and the like have been recently researched. Such an IoT environment can provide intelligent internet technology services, creating new value for human life by collecting and analyzing data generated between connected things. IoT can be applied in various fields including smart homes, smart buildings, smart cities, smart cars or networked cars, smart grids, healthcare, smart homes, and advanced medical services through fusion and combination between existing Information Technology (IT) and various industrial applications.

In response to this, various attempts have been made to apply the 5G communication system to the IoT network. For example, techniques such as sensor networks, Machine Type Communication (MTC), and machine-to-machine (M2M) communication may be implemented through beamforming, MIMO, and array antennas. The application of cloud Radio Access Network (RAN) as the big data processing technology described above can also be considered as an example of the convergence between 5G technology and IoT technology.

Since various services can be provided with the progress of the above-mentioned mobile communication system, a method for effectively providing the services is required.

Disclosure of Invention

Technical problem

The present disclosure relates to a method of allocating and distributing transmission power by an NR V2X UE when the UE performs communication over one or more links.

Technical scheme

The technical objects to be achieved in the embodiments of the present disclosure are not limited to the above-mentioned technical objects, and other technical objects not mentioned will be clearly understood from the following description by a person of ordinary skill in the art to which the present disclosure pertains.

In the disclosure for solving the above-mentioned problems, a method of a User Equipment (UE) in a wireless communication system includes: detecting a first side link transmission using a first Radio Access Technology (RAT) and a second side link transmission using a second RAT; determining whether the first sidelink transmission and the second sidelink transmission overlap; determining a sidelink to transmit if the first sidelink transmission and the second sidelink transmission overlap; and transmitting the side link information in the determined side link.

In some examples, determining the sidelink to transmit is determined based on priority information included in Sidelink Control Information (SCI).

In some examples, the transmission side link information is side link information whose priority included in the transmission priority information is high.

In some examples, the first RAT is fourth generation (4G) and the second RAT is fifth generation (5G).

In some examples, where the first sidelink transmission and the second sidelink transmission overlap, determining the sidelink to transmit is determined based on priority information indicated by a higher layer.

In some examples, the transmission side link information is a side link synchronization signal whose priority included in the transmission priority information is high.

In some examples, the transmission-side link information is determined based on priority information predetermined according to a type of a physical layer channel, and transmits a high-priority side link.

In some examples, the first side link transmission using the first RAT and the second side link transmission using the second RAT are determined based on a capability of the UE.

In another example of the present disclosure, a UE includes: a transceiver capable of transmitting and receiving at least one signal; and a controller coupled to the transceiver, wherein the controller is configured to: detecting a first side link transmission using a first Radio Access Technology (RAT) and a second side link transmission using a second RAT; determining whether the first sidelink transmission and the second sidelink transmission overlap; determining a sidelink to transmit if the first sidelink transmission and the second sidelink transmission overlap; and transmitting the side link information in the determined side link.

Technical effects

According to the proposed embodiments, when a V2X UE performs communication through one or more links, the transmission power of the UE is efficiently allocated and distributed, thereby enabling smooth communication.

Drawings

FIG. 1a is one example of a system for describing embodiments of the present disclosure.

Fig. 1b is another example of a system for describing embodiments of the present disclosure.

Fig. 1c is another example of a system for describing embodiments of the present disclosure.

Fig. 1d is another example of a system for describing embodiments of the present disclosure.

Fig. 2a is an example of a V2X communication method performed through a sidelink.

Fig. 2b is another example of a V2X communication method performed through a sidelink.

Fig. 3 is an example of a framework structure for V2X communication according to an embodiment of the present disclosure.

Fig. 4 is a diagram showing an example of a link through which an NR V2X UE can perform V2X communication.

Fig. 5a is one example of transmission power allocation for a V2X UE according to an embodiment of the present disclosure.

Fig. 5b is another example of transmission power allocation for a V2X UE according to an embodiment of the present disclosure.

Fig. 6a is another example of transmission power allocation for a V2X UE according to an embodiment of the present disclosure.

Fig. 6b is another example of transmission power allocation for a V2X UE according to an embodiment of the present disclosure.

Fig. 7 is a diagram illustrating a structure of a UE according to an embodiment of the present disclosure.

Fig. 8 is a diagram illustrating a structure of a base station according to an embodiment of the present disclosure.

Detailed Description

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

In the description of the embodiments of the present disclosure, a description of technical details that are well known in the art and have no direct relation to the present disclosure may be omitted. This is to more clearly convey the gist of the present disclosure by omitting unnecessary descriptions without causing ambiguity.

Also, in the drawings, some elements may be exaggerated, omitted, or summarized only briefly. In addition, the size of each element does not necessarily reflect the actual size. The same reference numbers will be used throughout the drawings to refer to the same or corresponding parts.

Advantages and features of the present disclosure and methods of accomplishing the same may be seen in the following detailed description of the embodiments when read in conjunction with the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed below, but may be implemented in various different ways, and the embodiments are provided only to complete the present disclosure and fully inform a person having ordinary skill in the art of the scope of the present disclosure, which is defined only by the scope of the claims. Like reference numerals are used to refer to like parts throughout the specification.

Also, it will be understood that blocks of the flowchart illustrations, and combinations of blocks in the flowchart illustrations, can be implemented by computer program instructions. These computer program instructions may be loaded onto a processor of a general purpose computer, special purpose computer, or programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or programmable data processing apparatus, create means for implementing the functions specified in the flowchart block or blocks. To implement the functions in some manner, the computer program instructions may also be stored in a computer usable or readable memory that is suitable for use by a special purpose computer or a programmable data processing apparatus, and the computer program instructions stored in the computer usable or readable memory may produce an article of manufacture including means for implementing the functions specified in the flowchart block or blocks. Since the computer program instructions may be loaded onto a computer or a programmable data processing apparatus, they may provide steps for performing the functions described in the blocks of the flowchart when the computer program instructions are executed as a process having a series of operations on the computer or the programmable data processing apparatus.

Further, each block of the flowchart illustrations may correspond to, or a portion of, a module, segment, or code containing one or more executable instructions for performing one or more logical functions. It should also be noted that, in some alternative implementations, the functions noted in the block may be performed in an order different than that listed. For example, two blocks listed in sequence may be executed substantially simultaneously or in reverse order according to the corresponding functions.

Here, the "unit", "module", and the like used in the present embodiment may refer to a software component or a hardware component, such as an FPGA or an ASIC capable of performing a certain function or operation. However, "unit" and the like are not limited to hardware or software. A unit or the like may be configured to reside in the addressable storage medium or to drive one or more processors. For example, a unit or the like may refer to a component such as a software component, an object-oriented software component, a class component or task component, a process, a function, an attribute, a program, a subroutine, a section of program code, a driver, firmware, microcode, circuitry, data, a database, a data structure, a table, an array, or a variable. The functionality provided by the components and units may be a combination of smaller components and units which may be combined with other components and units to form larger components and units. Further, the components and units may implement one or more processors in a drive device or a secure multimedia card. Further, in one embodiment, a unit or the like may include one or more processors.

In describing embodiments of the present disclosure in detail, a focus is mainly on a radio access network (new ran (nr)) and a packet core (5G system, 5G core network, or next generation core (NG core)), which is a core network according to the 5G mobile communication standard specified by 3GPP (mobile communication standardization organization), but those skilled in the art will appreciate that the subject matter of the present disclosure is applicable to other communication systems having similar technical backgrounds without significant modifications departing from the scope of the present disclosure.

In 5G systems, to support network automation, a network data collection and analysis function (NWDAF) may be defined, which is a network function that provides the functionality to analyze and provide data collected from the 5G network. The NWDAF may collect/store/analyze information from the 5G network and provide the results to unspecified Network Functions (NFs), and the analysis results may be used independently by each NF.

In the following, for convenience of description, some terms and names defined in the third generation partnership project long term evolution (3GPP) standards (standards of 5G, NR, LTE, or similar systems) may be used. However, the present disclosure is not limited by these terms and names, and may be equally applicable to systems conforming to other standards.

Also, in the following description, for convenience of description, terms identifying an access node, terms referring to network entities, terms referring to messages, terms referring to interfaces between network entities, and terms referring to various kinds of identification information are cited. Therefore, the present disclosure is not limited to the terms used, and other terms referring to entities having equivalent technical meanings may be used.

Since the commercialization of 4G communication systems, efforts have been made to develop improved 5G communication systems (NR, new air interface) in order to meet the ever-increasing demand for wireless data traffic. To achieve higher data rates, 5G communication systems have been designed to support extremely high frequency (mmWave) bands (e.g., 28GHz bands). In order to reduce the path loss of radio waves and increase the transmission distance of radio waves in the millimeter wave band, various techniques including beamforming, massive multiple input multiple output (massive MIMO), full-dimensional MIMO (FD-MIMO), array antenna, analog beamforming, and massive antenna are considered for the 5G communication system. Further, unlike LTE, the 5G communication system supports various subcarrier spacings, e.g., 15kHz, 30kHz, 60kHz, and 120kHz, the physical control channel uses polar coding, and the physical data channel uses Low Density Parity Check (LDPC). In addition, not only DFT-S-OFDM, but also CP-OFDM is used as a waveform for uplink transmission. Although LTE supports HARQ (hybrid ARQ) retransmission in units of Transport Blocks (TBs), 5G may additionally support HARQ retransmission based on Code Block Groups (CBGs) in which several Code Blocks (CBs) are bundled.

Further, in order to improve a system network in the 5G communication system, technical development is being performed regarding evolved small cells, advanced small cells, cloud radio access networks (cloud RANs), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, vehicle communication networks (vehicle-to-outside (V2X) networks), cooperative communication, coordinated multipoint (CoMP) communication, interference cancellation, and the like.

Meanwhile, the internet is evolving from a human-centric network in which humans create and consume information, such as the internet of things (IoT), in which distributed elements of things exchange and process information. Internet of everything (IoE) technology has also emerged, combining IoT technology with big data processing technology through connectivity to cloud servers. In order to implement IoT, technical elements related to sensing, wired/wireless communication, and network infrastructure, service interface, and security are required, and in recent years, technologies of internet of things such as sensor networks, machine-to-machine (M2M), or Machine Type Communication (MTC) are being researched. Under the IoT environment, intelligent Internet technology services can be provided, data generated by interconnection things can be collected and analyzed, and new value is added to human life. Through the fusion and combination of existing information technologies and various industries, the IoT technology can be applied to various fields, such as smart homes, smart buildings, smart cities, smart cars or networked cars, smart grids, healthcare, smart consumer electronics, and advanced medical services.

Therefore, various attempts are being made to apply the 5G communication system to the IoT network. For example, technologies such as sensor networks and machine-to-machine (M2M) or Machine Type Communication (MTC) are being implemented using 5G communication technologies, including beamforming, MIMO, and array antennas. The application of cloud RAN as the big data processing technology described above may be one example of the convergence of 3eG technology and IoT technology. Thus, in order to provide a plurality of services to a user in a communication system, a method capable of providing a single service according to its characteristics at the same time interval and an apparatus using the same are required. Various services provided in a 5G communication system are currently being studied, one of which is a service that satisfies low delay and high reliability requirements.

In terms of vehicle communications, LTE-based V2X standardization using device-to-device (D2D) communication structures has been done in 3GPP Rel-14 and Rel-15, and efforts are currently underway to develop 5G New Radio (NR) -based V2X. NR V2X is intended to support unicast, multicast (or multicast) and broadcast communications between UEs. Further, unlike LTE V2X, which is intended to transmit and receive basic safety information required for a vehicle to travel on a road, NR V2X is intended to provide more advanced services, such as queuing, advanced driving, extended sensors, and remote driving.

The NR V2X UE may perform uplink transmission to the NR base station or the LTE base station and may perform V2X communication with another NR V2X UE or LTE V2X UE. As an example, the NR V2X UE may perform a single transmission or simultaneous transmissions, as shown below.

-case of performing single transmission using one of NR uplink, LTE uplink, NR side link, and LTE side link

Case of performing synchronous transmission using two links

Simultaneous transmission of NR uplink and NR side link

Simultaneous transmission of NR uplink and LTE sidelink

Simultaneous transmission of NR uplink and LTE uplink

Simultaneous transmission of NR side link and LTE uplink

Simultaneous transmission of NR sidelink and LTE sidelink

Simultaneous transmission of LTE sidelink and LTE Uu

Case of performing synchronous transmission using three links

Simultaneous transmission of NR side link, LTE side link and NR uplink

Simultaneous transmission of NR sidelink, LTE sidelink and LTE uplink

Simultaneous transmission of NR side link, NR uplink and LTE uplink

Simultaneous transmission of NR uplink, LTE sidelink and LTE uplink

Case of performing synchronous transmission using four links

Simultaneous transmission of NR uplink, NR side link, LTE uplink and LTE side link

Which of the above scenarios can be supported can be determined according to the capabilities of the NR V2X UE.

An NR V2X UE that can only transmit over a single link may require a rule as to which of the four links described above should be used for transmission. Furthermore, since the NR V2X UE capable of transmitting simultaneously over two or more links limits its transmit power, it may have to distribute and allocate the transmit power appropriately so that it does not exceed its maximum transmit power.

Embodiments of the present specification are proposed to support the above-described scenarios, and are intended to provide a method and apparatus for NR V2X UE allocation and distribution of transmission power.

Fig. 1a, 1b, 1c, and 1d are examples of systems used to describe embodiments of the present disclosure.

Fig. 1a shows the case where all V2X UEs (UE-1 and UE-2) are located within the coverage of the base station.

All V2X UEs may receive data and control information from base station 103 through a Downlink (DL) or transmit data and control information to base station 103 through an Uplink (UL). Here, the data and control information may be data and control information of the V2X communication. Alternatively, the data and control information may be data and control information of conventional cellular communications. Further, V2X UEs may send and receive data and control information for V2X communications over Sidelink (SL).

FIG. 1b shows the case where the UE-1101 in the V2X UE is located within the coverage of the base station 103 and the UE-2102 is located outside the coverage of the base station 103. The illustration of FIG. 1b may be referred to as an example of partial coverage.

A UE-1101 located within the coverage of the base station 103 may receive data and control information from the base station 103 through a Downlink (DL) or may transmit data and control information to the base station 103 through an Uplink (UL).

A UE-2102 located outside the coverage of the base station 103 cannot receive data and control information of the base station 103 through a downlink, and cannot transmit data and control information to the base station 103 through an uplink.

The UE-2102 may send and receive data and control information for V2X communications to the UE-1101 over a sidelink.

Fig. 1c shows the case where all V2X UEs are located outside the coverage of the base station.

Therefore, the UE-1101 and the UE-2102 cannot receive data and control information from the base station through a downlink and cannot transmit data and control information to the base station through an uplink.

The UE-1101 and the UE-2102 can send and receive data and control information of V2X communication through a sidelink.

Fig. 1d shows a scenario where UEs located in different cells perform V2X communication. Specifically, fig. 1d shows the case where the V2X transmitting UE and the V2X receiving UE are connected to or camped on different base stations (RRC connected state) or (RRC connection released state, i.e., RRC idle state). Here, the UE-1101 may be a V2X transmitting UE, and the UE-2102 may be a V2X receiving UE. Alternatively, the UE-1101 may be the V2X receiving UE, and the UE-2102 may be the V2X transmitting UE. The UE-1101 may receive a V2X-specific System Information Block (SIB) from the base station 103 to which it is connected (or on which it resides), and the UE-2102 may receive a V2X-specific SIB from another base station 104 to which it is connected (or on which it resides). Here, the information of the V2X-specific SIB received by the UE-1101 and the information of the V2X-specific SIB received by the UE-2102 may be different from each other. Therefore, in order for UEs located in different cells to perform V2X communication, it is necessary to standardize the information.

For ease of description, fig. 1a, 1b, 1c, and 1d illustrate, but are not limited to, a V2X system consisting of two UEs (UE-1 and UE-2). Further, the uplink and downlink between the base station and the V2X UE may be referred to as the Uu interface, and the sidelink between the V2X UE may be referred to as the PC5 interface. Accordingly, these may be used interchangeably in this disclosure.

Meanwhile, in the present disclosure, the UE 101 or 102 may refer to a vehicle supporting vehicle-to-vehicle (V2V) communication, a vehicle or pedestrian phone (i.e., a smartphone) supporting vehicle-to-pedestrian (V2P) communication, a vehicle supporting vehicle-to-network (V2N) communication, or a vehicle supporting vehicle-to-infrastructure (V2I) communication. In addition, in the present disclosure, a UE may refer to a Road Side Unit (RSU) equipped with a UE function, an RSU equipped with a base station function, or an RSU equipped with a part of a base station function and a part of a UE function.

Further, the present disclosure predefines that the base station 103 may be a base station supporting both V2X communications and conventional cellular communications, or a base station supporting only V2X communications. Also, in this case, the base station may refer to a 5G base station (gNB), a 4G base station (eNB), or a Road Site Unit (RSU). Thus, unless otherwise specified in the disclosure, a base station and an RSU may be used interchangeably as they are used as the same concept.

Fig. 2a and 2b are examples of the V2X communication method performed through a side link.

As shown in fig. 2a, the TX UE and the RX UE may perform communication in a one-to-one manner, which may be referred to as unicast communication.

As shown in fig. 2b, the TX UE and the RX UE may perform communication in a one-to-many manner, which may be referred to as multicast or multicast.

FIG. 2B depicts a case where UE-1201, UE-2202, and UE-3203 form one group (group A) to perform multicast communication and UE-4204, UE-5205, UE-6206, and UE-7207 form another group (group B) to perform multicast communication. Each UE performs multicast communication only within the group to which it belongs, and does not perform communication between different groups. Fig. 2b illustrates the formation of two groups, but is not limited thereto.

Meanwhile, although not shown in fig. 2a and 2b, the V2X UE may perform broadcast communication. Broadcast communication refers to a case where all V2X UEs receive data and control information transmitted by the V2X transmitting UEs through a sidelink. For example, assuming that UE-1 is the transmitting UE for broadcasting in FIG. 2b, all UEs (UE-2, UE-3, UE-4, UE-5, UE-6, UE-7) can receive data and control information transmitted by UE-1201.

Fig. 3 is an example of a framework structure for V2X communication according to an embodiment of the present disclosure.

Fig. 3 shows, but is not limited to, the system operating 1024 radio frames. For example, a particular system may operate less than or more than 1024 radio frames, and the number of radio frames operated by the system may be configured to the UE by the base station with a Master Information Block (MIB) transmitted through a Physical Broadcast Channel (PBCH), or may be a fixed value previously agreed with the UE. In fig. 3, the radio frame number and the system frame number may be considered the same. That is, the radio frame number '0' may correspond to the system frame number '0', and the radio frame number '1' may correspond to the system frame number '1'. One radio frame is 10 msec long on the time axis and may be composed of 10 subframes. That is, the length of one subframe on the time axis may be 1 millisecond. The subcarrier spacing available for NR V2X communication may be expressed as 15kHz x²ⁿWherein n is an integer having a value of 0, 1, 2, 3. As shown in fig. 3, in NR V2X, a slot constituting one subframe is 2ⁿIt may vary according to subcarrier spacing. For example, when a subcarrier spacing of 15kHz is used, one subframe may consist of one slot (n ═ 0). In addition, when subcarrier intervals of 30kHz, 60kHz, and 120kHz are used, one subframe may be composed of 2 slots (n ═ 1), 4 slots (n ═ 2), and 8 slots (n ═ 3), respectively. Although not shown in fig. 3, one slot may be composed of 14 Orthogonal Frequency Division Multiplexing (OFDM) symbols or discrete fourier transform spread OFDM (DFT-S-OFDM) symbols regardless of the sub-carrier spacing. The above can be summarized as the following table 1 (physical layer parameters according to subcarrier spacing).

[ Table 1]

Fig. 4 shows an example of a link through which an NR V2X UE can perform V2X communication.

Specifically, the V2X communication may be performed through at least one of the following links.

The link between an-NR V2X UE401 and another NR V2X UE 405 may be referred to as an NR side link. The NR V2X UE401 may send sidelink control information and data information for NR V2X communications to another NR V2X UE 405 over an NR sidelink. Further, the NR V2X UE401 may receive side link control information and data information of the NR V2X communication from another NR V2X UE 405 through an NR side link.

The link between the-NR V2X UE401 and the LTE V2X UE 404 may be referred to as LTE sidelink. Here, the NR V2X UE401 may be assumed to have the capability to support LTE V2X communication. The NR V2X UE401 may transmit and receive control information and data information for LTE V2X communications over LTE sidelinks.

The downlink or uplink between the-NR V2X UE401 and NR base station 403(gNB) may be named NR Uu.

NR V2X UE401 may receive control information and data information related to NR side link transmission and reception from NR base station 403(gNB) through NR Uu. Further, the NR V2X UE401 may transmit NR side link control information and data information received from another NR V2X UE 405 to the gNB 403 through NR Uu.

NR V2X UE401 may receive control information and data information related to LTE sidelink transmission and reception from NR base station 403(gNB) through NR Uu. Further, the NR V2X UE401 may transmit LTE sidelink control information and data information received from the LTE V2X UE 404 to the gNB 403 through NR Uu. Here, the NR V2X UE401 may be assumed to have the capability to support LTE V2X communication.

The downlink or uplink between the NR V2X UE401 and the LTE base station 402(eNB) may be named LTE Uu.

NR V2X UE401 may receive control information and data information related to NR side link transmission and reception from an LTE base station 402(eNB) through LTE Uu. Further, the NR V2X UE401 may transmit NR side link control information and data information received from another NR V2X UE 405 to the eNB 402 through the LTE Uu. Here, it can be assumed that the NR V2X UE401 has the capability of supporting LTE Uu.

NR V2X UE401 may receive control information and data information related to LTE sidelink transmission and reception from eNB 402 over LTE Uu. Further, the NR V2X UE401 may transmit LTE sidelink control information and data information received from the LTE V2X UE 404 to the eNB 402 through the LTE Uu. Here, it may be assumed that the NR V2X UE401 has the capability of supporting LTE V2X communication, and also has the capability of supporting LTE Uu.

A particular NR V2X UE401 may perform V2X communications and cellular communications by using one or more links shown in fig. 3 at the same time. In particular, when the NR V2X UE performs communication using two or more links at the same time, there may be the following scenarios.

Scenario 1) case of simultaneous transmission using two links

NR Uu + NR side chain: the NR V2X UE401 may send NR V2X control information and data information to the gNB 403 (or may send uplink control information and data information for NR cellular communications to the gNB 403) over the NR Uu, while control information and data information for NR V2X communications may be sent to another NR V2X UE 405 over the NR side chain.

NR Uu + LTE side chain: the NR V2X UE401 may transmit NR V2X control information and data information to the gNB 403 through NR Uu (or may transmit uplink control information and data information for NR cellular communications to the gNB 403), and, at the same time, may transmit control information and data information for LTE V2X communications to the LTE V2X UE 404 through an LTE sidelink.

NR Uu + LTE Uu: the NR V2X UE401 may transmit NR V2X control information and data information (or may transmit uplink control information and data information of NR cellular communication) to the gNB 403 through the NR Uu, and at the same time, may transmit LTE V2X control information and data information to the eNB 402 through the LTE Uu (or may transmit uplink control information and data information of LTE cellular communication to the eNB 402). In this scenario, since NR V2X control information and data information are not transmitted through the NR side link, it cannot be regarded as an operation of the NR V2X UE. Since the present disclosure is directed to identifying the operation of NR V2X UEs, such scenarios may be excluded from the present disclosure.

NR sidelink + LTE Uu: the NR V2X UE401 may send control information and data information for NR V2X communications to another NR V2X UE 405 through an NR side chain, while NR V2X control information and data information may be sent to the gNB 403 through an NR Uu (or uplink control information and data information for NR cellular communications may be sent to the gNB 403).

NR side link + LTE side link: the NR V2X UE401 may send control information and data information for NR V2X communications to another NR V2X UE 405 through an NR sidechain, while control information and data information for LTE V2X communications may be sent to an LTE V2X UE 404 through an LTE sidechain.

LTE sidelink + LTE Uu: the NR V2X UE401 may transmit control information and data information for LTE V2X communications to the LTE V2X UE 404 over an LTE sidechain, while LTE V2X control information and data information may be transmitted to the eNB 402 over an LTE Uu (or uplink control information and data information for LTE cellular communications may be transmitted to the eNB 402). In this scenario, since control information and data information are not transmitted through the NR Uu or NR side link, it cannot be regarded as an operation of the NR V2X UE (i.e., can be regarded as an operation of the LTE V2X UE). Since the present disclosure is directed to identifying the operation of NR V2X UEs, such scenarios may be excluded from the present disclosure.

Scenario 2) case of simultaneous transmission using three links

NR sidelink + LTE sidelink + NR Uu: the NR V2X UE401 may transmit control information and data information of NR V2X communication and LTE V2X communication, respectively, through NR side link and LTE side link, and at the same time, may transmit NR V2X control information or data information to the gNB 403 through NR Uu (or may transmit uplink control information and data information of NR cellular communication to the gNB 403).

NR Uu + NR sidelink + LTE Uu: the NR V2X UE401 may send NR V2X control information and data information to the gNB 403 (or uplink control information and data information for NR cellular communications to the gNB 403) through the NR Uu, and may send control information and data information for NR V2X communications to another NR V2X UE 405 through the NR side chain. Meanwhile, the NR V2X UE401 may transmit LTE V2X control information and data information to the eNB 402 through LTE Uu (or may transmit uplink control information and data information of LTE cellular communication to the eNB 402).

NR Uu + LTE sidelink + LTE Uu: the NR V2X UE401 may transmit NR V2X control information or data information to the gNB 403 (or transmit uplink control information and data information for NR cellular communications to the gNB 403) through the NR Uu and may transmit control information and data information for LTE V2X communications to the LTE V2X UE 404 through the LTE sidechain. Meanwhile, the NR V2X UE401 may transmit LTE V2X control information or data information to the eNB 402 through LTE Uu (or may transmit uplink control information and data information of LTE cellular communication to the eNB 402).

NR sidelink + LTE Uu: the NR V2X UE401 may transmit control information and data information of NR V2X communication and LTE V2X communication, respectively, through NR side link and LTE side link, and may simultaneously transmit LTE V2X control information or data information to the eNB 402 through LTE Uu (or may transmit uplink control information and data information of LTE cellular communication to the eNB 402).

Scenario 3) case of simultaneous transmission using four links

NR Uu + NR side link + LTE Uu + LTE side link: the NR V2X UE401 may send NR V2X control information or data information to the gNB 403 (or uplink control information and data information for NR cellular communications to the gNB 403) through the NR Uu and may send control information and data information for NR V2X communications to another NR V2X UE 405 through the NR side chain. Meanwhile, the NR V2X UE401 may transmit LTE V2X control information or data information to the eNB 402 (or transmit uplink control information and data information of LTE cellular communication to the eNB 402) over LTE Uu and may transmit LTE V2X control information or data information to the LTE V2X UE 404 over LTE sidelink.

Although not mentioned in the above examples, a Carrier Aggregation (CA) technique may be combined with each of the scenarios described above. For example, the NR V2X UE401 may transmit NR control information and data information using one or more NR Uu links by using NR Uu CA. Further, the NR V2X UE401 can transmit control information and data information of NR V2X by using NR side links CA with one or more NR side links. Likewise, the NR V2X UE401 may utilize one or more LTE Uu links to transmit LTE control information and data information by using LTE Uu CA. Also, the NR V2X UE may transmit control information and data information of LTE V2X with one or more LTE sidelinks by using LTE sidelinks CA.

The NR V2X UE401 may need to perform transmission on a single link or support at least one scenario of the above example according to its capabilities. Thus, a NR V2X UE401 capable of only single link transmission may need to allocate transmit power only to a particular link. Further, an NR V2X UE capable of simultaneous transmission using two or more links may need to allocate and distribute transmission power to the respective links. There may be various methods of allocating and distributing transmission power, and one of the methods mentioned in fig. 5a, 5b, 6a, and 6b may be applied.

Fig. 5a and 5b are examples of allocating transmit power of a V2X UE according to an embodiment of the present disclosure.

In fig. 5a and 5b, P _ NR may represent a maximum transmission power available for NR transmission, and P _ LTE may represent a maximum transmission power available for LTE transmission. In addition, P1 may represent a transmission power actually used for NR transmission, and P2 may represent a transmission power actually used for LTE transmission. Here, since the actually used transmission power cannot be greater than the allowed maximum transmission power P1 ≦ P _ NR and P2 ≦ P _ LTE, P1 ≦ P _ NR and P2 ≦ P _ LTE in FIGS. 5a and 5b should be satisfied. Further, P _ Total shown in fig. 5a and 5b is a maximum transmission power value allowed when the NR link and the LTE link are simultaneously transmitted. Here, P _ NR, P _ LTE, P1, P2, and P _ Total have linear values not in units of dB or dBm.

Fig. 5a shows a case where the sum of P _ NR and P _ LTE is less than P _ Total, and fig. 5b shows a case where the sum of P _ NR and P _ LTE is greater than P _ Total. The case where the sum of P _ NR and P _ LTE is equal to P _ Total is not shown in fig. 5a and 5b, but it may be included in the category of fig. 5 a. Furthermore, fig. 5a shows P _ NR ═ P _ LTE, and fig. 5b shows P _ NR > P _ LTE. However, this is only one example, and the method described in the present disclosure can be applied even in the scenario of P _ NR < P _ LTE.

In fig. 5a and 5b, NR transmission may refer to simultaneous transmission of NR Uu and NR side links, or transmission through one link of NR Uu and NR side links. In addition, LTE transmission may refer to simultaneous transmission of LTE Uu and LTE side link, or transmission through one link of LTE Uu and LTE side link.

After completing RRC connection with a base station (RRC connected mode), the NR V2X UE may configure information on P _ NR _ dBm, P _ LTE _ dBm, and P _ Total _ dBm through UE-specific RRC parameters (here, P _ NR _ dBm is 10log10(P _ NR), P _ LTE _ dBm is 10log10(P _ LTE), and P _ Total _ dBm is 10log10(P _ Total)). For example, when a V2X UE establishes an RRC connection with an NR base station (gNB), the V2X UE may receive corresponding information from the gNB. When the V2X UE establishes an RRC connection with an LTE base station (eNB), the V2X UE may receive information about P _ NR _ dBm, P _ LTE _ dBm, and P _ Total _ dBm from the eNB. As another example, when the V2X UE establishes an RRC connection with both the gNB and the eNB, it may receive information from the primary node regarding P _ NR _ dBm, P _ LTE _ dBm, and P _ Total _ dBm. More specifically, the above case may be considered as a Dual Connectivity (DC) scenario, and in an LTE-NR DC environment in which the eNB serves as a primary node, the eNB may configure corresponding information as RRC parameters to the NR V2X UE. In addition, in an NR-LTE DC environment where the gNB serves as a primary node, the gNB may configure corresponding information as an RRC parameter to the NR V2X UE.

On the other hand, P _ NR _ dBm, P _ LTE _ dBm, and P _ Total _ dBm may be configured from a base station (gNB or eNB) where the V2X UE is located through system information (system information block, SIB) instead of UE-specific RRC configuration. Here, the V2X UE may be in a state in which RRC connection establishment is not performed with the base station in which it is located (i.e., RRC idle state).

From the perspective of the base station, when there is an interface between the gNB and the eNB, the gNB and the eNB may negotiate to set the P _ NR and P _ LTE values through the interface. In this case, the sum of P _ NR and P _ LTE may be set to be less than or equal to P _ Total. However, when there is no interface between the gNB and eNB, the gNB and eNB can set the P _ NR and P _ LTE values independently without negotiating the P _ NR, P _ LTE, and P _ Total values. Therefore, a case may occur at a certain time in which the sum of P _ NR and P _ LTE is greater than P _ Total (P _ NR + P _ LTE > P _ Total).

On the other hand, from the viewpoint of the NR V2X UE, when there is an interface between the NR modem and the LTE modem, the NR modem and the LTE modem can exchange information about P1 and P2. In this case, even if the base station performs the configuration to make P _ NR + P _ LTE > P _ Total in the above example, the NR V2X UE can adjust the transmission power value so that the sum of P1 and P2 is less than or equal to P _ Total (P1+ P2 ≦ P _ Total) by exchange of information on the transmission power value between the NR modem and the LTE modem. UEs with this capability may be identified as UEs capable of dynamic power allocation between NR and LTE. On the contrary, when there is no interface between the NR modem and the LTE modem, information on P1 and P2 cannot be exchanged. In this case, if the base station is configured such that P _ NR + P _ LTE > P _ Total in the above example is established, transmission may have to be performed using only one of the NR link and the LTE link. A UE with such capability may be identified as a UE capable of Single Uplink Operation (SUO) between NR and LTE.

Next, a detailed description will be made of a transmission power allocation operation according to the capability of the UE in various scenario environments exemplified above.

NR V2X UEs that do not have the capability to perform synchronous transmission over NR and LTE links are unable to perform synchronous transmission over NR and LTE links. Therefore, such a UE can transmit (SUO) using only one of the NR link and the LTE link. In this case, one of the following methods can be applied to which link should be used for transmission.

The NR V2X UE may perform transmission using only one link according to a preset rule. For example, the NR V2X UE may perform transmission only over the link of the base station for which the RRC connection has been established. That is, if the NR V2X UE has established an RRC connection with the gNB, it may set the transmission power to P1 and transmit through the NR link. If the NR V2X UE has established an RRC connection with the eNB, it may set the transmission power to P2 and transmit over the LTE link. The NR V2X UE can only transmit over the link connected to the primary node if it has established an RRC connection with the gNB and eNB. For example, when the gNB is the primary node, the NR V2X UE may set the transmission power to P1 and transmit over the NR link. When the eNB is the primary node, the NR V2X UE may set the transmission power to P2 and transmit over the LTE link.

As another example, unlike the above example, according to the priority of the physical channel transmitted through each link, transmission of the link through which the channel having the low priority is transmitted may be abandoned, and transmission may be performed only on the link through which the channel having the high priority is transmitted. For example, a control channel may have a higher priority than a data channel. That is, when the control channel is transmitted through the NR link and the data channel is transmitted through the LTE link, the transmission can be performed only at the NR link through which the control channel is transmitted. On the other hand, there may be a case where the control channel is transmitted on the NR link and the LTE link. In this case, the priority set in advance for each channel may be followed. Specific examples of this aspect will be described in detail later.

As another example, the NR V2X UE may perform transmission over only one link according to the priority provided by the base station through RRC configuration. More specifically, the gNB or eNB may configure priority values for NR V2X UEs based on the type of data transmitted over the NR link and the LTE link via RRC parameters. Based on the configured priority values, the NR V2X UE may abandon transmission on the link over which low priority data is transmitted and may perform transmission only on the link over which high priority data should be transmitted.

The NR V2X UE capable of performing simultaneous transmission on the NR link and the LTE link may perform the following operations according to the setting of the base station.

-when P _ NR + P _ LTE ≦ P _ Total is set by the base station

The NR V2X UE may perform synchronous transmission on the NR link and the LTE link by setting transmission power of the NR link and the LTE link to P1 and P2, respectively. Here, the base station may perform configuration such that P1P _ NR ≦ and P2 ≦ P _ LTE hold.

-when P _ NR + P _ LTE > P _ Total is set by the base station

NR V2X UE with dynamic power allocation capability may adjust the transmit power value such that P _ NR + P _ LTE ≦ P _ Total holds, and one of the following methods may be applied.

NR V2X UE may adjust the transmit power values of the NR link and the LTE link at the same time. More specifically, the transmission power value of the NR link may be decreased by w1 × P _ NR, and the transmission power value of the LTE link may be decreased by w2 × P _ LTE. Here, w1 × P _ NR + w2 × P _ LTE ≦ P _ Total should be true. w1 and w2 refer to scaling factors for NR and LTE links, respectively, and may have values between 0 and 1. The NR V2XUE can adjust the transmission power value by determining w1 and w2 values satisfying the conditions of 0. ltoreq. w 1. ltoreq.1 and 0. ltoreq. w 2. ltoreq.1. As another example, the NR V2X UE may adjust the transmit power value by determining w1 and w2 values that satisfy the condition 0 ≦ w1+ w2 ≦ 1, where w1+ w2 has a value between 0 and 1.

NR V2X UEs may reduce the transmit power value of the NR link without changing the transmit power value of the LTE link. This may mean a variation of the above example where w2 is always set to 1. Here, w1 may have a value between 0 and 1. Such a scenario may apply, but is not limited to, when the NR V2X UE has established an RRC connection with the eNB (no RRC connection with the gNB) or when the eNB is configured as a primary node (RRC connection is established with both the gNB and the eNB).

As another variation of the above example, w1 is always set to 1, and w2 may have a value between 0 and 1. Such a scenario may apply, but is not limited to, when the NR V2X UE has established an RRC connection with the gNB (no RRC connection with the eNB) or when the gNB is configured as a primary node (RRC connection is established with both the gNB and the eNB).

As another example, according to the priority of the physical channel transmitted through each link, a case where a channel of low priority has a lower transmission power value than a channel of high priority may be considered. For example, assuming that the control channel has a higher priority than the data channel, the scale factor for the control channel may be defined as α and the scale factor for the data channel may be defined as β. Here, α and β may each have a value between 0 and 1, and the α value may always be smaller than the β value. Therefore, when the control channel is transmitted through the NR link and the data channel is transmitted through the LTE link, the transmission power value may be adjusted so that α × P _ NR + β × P _ LTE ≦ P _ Total is established. Conversely, when the control channel is transmitted through the LTE link and the data channel is transmitted through the NR link, the transmission power value may be adjusted so that β × P _ NR + α × P _ LTEP _ Total is equal to or less than unity. On the other hand, there may be a case where both the NR link and the LTE link transmit a control channel or both transmit a data channel. In this case, the priority set in advance for each channel may be followed. Detailed examples of this will be described later.

Meanwhile, for an NR V2X UE without dynamic power allocation capability, since information on transmission power allocation cannot be exchanged between the NR modem and the LTE modem of the UE, the transmission power value cannot be adjusted so that P _ NR + P _ LTE ≦ P _ Total holds. Therefore, one of the above-described SUO methods may be applied to set the transmission power value.

In the above examples, the method of allocating transmission power to the NR link and the LTE link has been described. However, the NR link may be composed of NR Uu and NR side links, and the LTE link may be composed of LTE Uu and LTE side links. Therefore, it may be necessary to reallocate the transmission power that has been allocated to the NR link and the LTE link to each Uu and sidelink of the NR link and the LTE link. One of the following methods can be regarded as a method of transmission power reallocation.

[ method of allocating Transmission Power to LTE Uu and LTE sidelink ]

The transmission power allocated to the LTE link may be reallocated to the LTE Uu and LTE side links by employing at least one of the following methods.

-method 1: allocating transmission power according to predetermined priority

The transmit power may be assigned to the LTE Uu and LTE sidelink according to a predetermined priority. In this case, the priority may be determined according to the type of physical layer channel transmitted through Uu and the sidelink. In addition, it can be assumed that transmission via Uu and the sidelink is performed in the same cell or the same Component Carrier (CC) at this time. For example, when the physical layer random access channel is transmitted through Uu and at the same time the sidelink control information and the data information are transmitted through the sidelink, the UE may abandon the sidelink transmission and perform Uu link transmission (i.e., the transmission power allocated to the LTE link is allocated such that the transmission power of the sidelink is set to 0 and the remaining transmission power is used for Uu transmission). Conversely, when a physical layer channel other than the random access channel (e.g., a physical layer uplink data channel or a physical layer uplink control channel) is transmitted through Uu and at the same time, the UE may give up Uu transmission and perform sidelink transmission (i.e., transmission power allocated to the LTE link is allocated such that transmission power of Uu is set to 0 and the remaining transmission power is used for sidelink transmission).

As another example, a case where CA is applied to the sidelink may be considered. That is, it may refer to a case in which sidelink control information and data are transmitted through two or more carriers and Uu transmission is simultaneously performed. In this case, the sidelink transmission may not be performed on the bearer on which the Uu transmission is performed. For example, it may refer to a case where Uu transmission is performed on component carrier 1(CC #1) and side-link transmission is performed on component carrier 2(CC #2) and component carrier 3(CC # 3). In this case, while maintaining the transmission power for Uu transmission, the sidelink transmission power may be reduced such that the sum of the transmission power for sidelink transmission and the transmission power for Uu transmission is less than or equal to the maximum transmission power (Pcmax) of the UE. On the other hand, when the sidelink transmission is performed on the carrier on which the Uu transmission is performed, as in the case where the simultaneous transmission of the Uu and the sidelink is performed in the same cell as described above, the transmission power may be allocated to the Uu or the sidelink based on the preset priority according to the physical layer.

-method 2: allocating transmit power according to configured priority

eNB may configure the threshold of priority to the UE through System Information (SIB) or UE-specific RRC configuration. Also, the UE may receive a priority value of a side link to be transmitted by the UE from a higher layer (e.g., an application layer) of the UE. Here, it can be assumed that Uu and sidelink transmission are performed in the same cell or the same component carrier. The UE may compare the threshold for priority configured by the eNB to a priority value for a sidelink to be transmitted by the UE. When the priority value of the sidelink is less than the threshold configured by the eNB (smaller value takes precedence), the UE may give up Uu transmission and perform sidelink transmission (i.e., the transmission power allocated to the LTE link is allocated such that the transmission power of Uu is set to 0, and the remaining transmission power is used for sidelink transmission). Conversely, when the priority value of the sidelink is greater than the threshold configured by the eNB, the UE may abandon sidelink transmission and perform Uu transmission (i.e., the transmission power allocated to the LTE link is allocated such that the transmission power of the sidelink is set to 0 and the remaining transmission power is used for Uu transmission).

As another example, a case where CA is applied to the sidelink may be considered. That is, it may refer to a case where sidelink transmission is performed through two or more carriers and Uu transmission is performed at the same time. In this case, the sidelink transmission may not be performed on the bearer on which the Uu transmission is performed. For example, it may refer to a case where Uu transmission is performed on component carrier 1(CC #1), and side-link transmission is performed on component carrier 2(CC #2) and component carrier 3(CC # 3). In this case, when the priority value of the sidelink is smaller than the threshold configured by the eNB (smaller value takes precedence), the UE may adjust the transmission power for Uu transmission while maintaining the transmission power for sidelink transmission. Here, the Uu transmission power may be reduced such that the sum of the transmission power for the sidelink transmission and the transmission power for the Uu transmission is less than or equal to the maximum transmission power (Pcmax) of the UE. Conversely, when the priority value of the sidelink is greater than the threshold configured by the eNB, the UE may adjust the transmit power for sidelink transmissions while maintaining the transmit power for Uu transmissions. Here, the sidelink transmission power may be reduced such that the sum of the transmission power for Uu transmission and the transmission power for sidelink transmission is less than or equal to the maximum transmission power (Pcmax) of the UE. On the other hand, when the sidelink transmission is performed on the carrier through which the Uu transmission is performed, the transmission power allocation method can be applied as in the case where the Uu and sidelink transmission are performed in the same cell or the same component carrier as described above.

[ method of allocating Transmission Power to NR Uu and NR side links ]

The transmission power allocated to the NR link may be reallocated to the NR Uu and NR side links by employing at least one of the following methods.

-method 1: the transmission power is allocated according to a predetermined priority-the transmission power can be allocated to the NR Uu and NR side links according to a predetermined priority. More specifically, the transmission power of the channel having the low priority can be adjusted while maintaining the transmission power of the channel having the high priority. Here, the transmission power of the low priority channel may be reduced such that the sum of the transmission power for Uu transmission and the transmission power for sidelink transmission is less than or equal to the maximum transmission power (Pcmax) of the UE. There are various methods to define the priority, and at least one of the following methods may be used.

When Uu and sidelink transmissions are performed in the same cell or same component carrier, the Uu transmission may always have a higher priority than sidelink transmissions. In this case, the V2X UE may set the sidelink transmission power to 0 (drop or discard sidelink transmission) and perform Uu transmission (i.e., the transmission power allocated to the NR link is allocated such that the transmission power of the sidelink is set to 0 and the remaining transmission power is used for Uu transmission). The above example may be equally applicable to the case where Uu and sidelink transmissions are performed in different cells or different component carriers.

Priority may be determined according to the type of physical layer channel transmitted through Uu and sidelink. For example, when a Physical Random Access Channel (PRACH) transmits over Uu while performing sidelink transmissions, the UE may abandon sidelink transmissions and perform Uu link transmissions. This may mean that the PRACH of Uu always has a high priority regardless of the physical layer channel transmitted over the sidelink. The above example may be applicable to a case where Uu and sidelink transmission are performed in different cells (or different component carriers) and a case where Uu and sidelink transmission are performed in the same cell.

As another example of determining the priority according to the type of physical layer channel transmitted through Uu and sidelink, the following case may be considered. Physical layer channels and signals transmitted over Uu may include a random access channel (PRACH), an uplink control channel (physical uplink control channel, PUCCH), an uplink data channel (physical uplink shared channel, PUSCH), and a sounding signal (sounding reference signal, SRS). The physical layer channels and signals transmitted through the sidelink may include a sidelink synchronization channel (sidelink synchronization signal block, S-SSB), a sidelink control channel (physical sidelink control channel, PSCCH), a sidelink data channel (physical sidelink shared channel, PSCCH), a sidelink feedback channel (physical sidelink feedback channel, PSFCH), and a sidelink reference signal (sidelink channel state information reference signal, S-CSI-RS). The priority may be defined using one of the following methods according to various combinations of the above channels.

Example 1: uu channels may have higher priority than sidelink channels, and Uu or control channels in sidelink may have higher priority than data channels. For example, PRACH > PUCCH with HARQ-ACK and/or SR (scheduling request) or PUSCH with HARQ-ACK > PSFCH with HARQ-ACK or PSCCH with HARQ-ACK > PUCCH with CSI or PUSCH with CSI > PSFCH with CSI or PSCCH with CSI > PUSCH > PSCCH > SRs > S-CSI-RS. In the above example, the PSCCH and PSCCH may have the same priority. In addition, in the above example, the SRS and the S-CSI-RS may have the same priority. The above example may be applicable to a case where Uu and sidelink transmission are performed in different cells (or different CCs), and a case where Uu and sidelink transmission are performed in the same cell (or the same CC).

Example 2: the sidelink channel may be prioritized over the Uu channel, and the control channel in the sidelink or Uu may be prioritized over the data channel. For example, PSFCH with HARQ-ACK or psch with HARQ-ACK > PRACH > PUCCH with HARQ-ACK and/or SR (scheduling request) or PUSCH with HARQ-ACK > PSFCH with CSI or psch with CSI > PUCCH with CSI or PUSCH with CSI > PSCCH > PUSCH > S-CSI-RS > SRs. As another example, in the above example, the PRACH may have the highest priority. Namely, PRACH > PSFCH with HARQ-ACK or SSCH with HARQ-ACK > PUCCH with HARQ-ACK and/or SR (scheduling request) or PUSCH with HARQ-ACK > PSFCH with CSI or PSCCH with CSI > PUCCH with CSI or PUSCH with CSI > PSCCH > PUSCH > S-CSI-RS > SRs. In the above example, the PSCCH and PSCCH may have the same priority. In addition, in the above example, the SRS and the S-CSI-RS may have the same priority. The above example may be applicable to a case where Uu and sidelink transmission are performed in different cells (or different CCs), and a case where Uu and sidelink transmission are performed in the same cell (or the same CC).

-method 2: allocating transmit power according to configured priority

The NR V2X UE may transmit Sidelink Control Information (SCI) to control its transmission over the PSCCH, PSFCH, or S-CSI-RS transmitted by the PSCCH. Here, the NR V2X UE may receive priority information of a psch, PSFCH, or S-CSI-RS transmission to be transmitted by it from a higher layer (e.g., an application layer). The priority information may be composed of N bits and may be included in the SCI. For example, if the priority information is composed of 3 bits, 000 indicates a priority "0", and 111 indicates a priority "7", so it can be seen that there is a total of 8 priorities. Here, a smaller value may be prioritized. The gNB may configure the priority thresholds of the NR Uu and NR side links to the UE through System Information (SIB) or UE-specific RRC configuration. The NR V2XUE may compare the priority threshold configured by the gNB with the priority value included in the SCI field described above. When the priority value of the sidelink is less than the threshold configured by the gNB, the NR V2X UE may give up Uu transmission and perform sidelink transmission (i.e., the transmission power allocated to the NR link is allocated such that the transmission power of Uu is set to 0 and the remaining transmission power is used for sidelink transmission). Conversely, when the priority value of the sidelink is greater than the threshold configured by the eNB, the UE may abandon sidelink transmission and perform Uu transmission (i.e., the transmission power allocated to the NR link is allocated such that the transmission power of the sidelink is set to 0 and the remaining transmission power is used for Uu transmission). This operation may be applied when CA is not applied to a sidelink, or when CA is applied to a sidelink but a cell (or CC) in which NR Uu is transmitted and a cell in which a sidelink is transmitted are the same.

As another example, there may be a case where CA is applied to the sidelink (i.e., sidelink transmission is over two or more carriers) and sidelink transmission is not over the carrier over which Uu is transmitted. For example, it may refer to a case where Uu transmission is performed on component carrier 1(CC #1) and side-link transmission is performed on component carrier 2(CC #2) and component carrier 3(CC # 3). In this case, when the priority value of the sidelink included in the SCI is less than the threshold configured by the gNB, the UE may adjust the transmission power for Uu transmission while maintaining the transmission power for sidelink transmission. Here, the Uu transmission power may be reduced such that the sum of the transmission power for the sidelink transmission and the transmission power for the Uu transmission is less than or equal to the maximum transmission power (Pcmax) of the UE. Conversely, when the priority value of the sidelink is greater than the threshold configured by the gNB, the UE may adjust the transmit power for sidelink transmissions while maintaining the transmit power for Uu transmissions. Here, the sidelink transmission power may be reduced such that the sum of the transmission power for Uu transmission and the transmission power for sidelink transmission is less than or equal to the maximum transmission power (Pcmax) of the UE. On the other hand, when the sidelink transmission is performed on the carrier through which the Uu is transmitted, a transmission power allocation method may be applied, such as the case where the Uu and the sidelink transmission are performed in the same cell or the same component carrier as described above.

Fig. 5a and 5b may be applied to the case where "scenario 3) mentioned in fig. 4 is transmitted using four links simultaneously (NR Uu + NR side link + LTE Uu + LTE side link)". However, since the scene 3) includes the scene 1) and the scene 2), the above description is not limited to the scene 3), and can be extended to the scene 1) and the scene 2). For example, to explain how the transmission power allocation method of scenario 3) is applied to scenario 2), the transmission power allocation method of simultaneously transmitting "NR-side link + LTE Uu" in scenario 2) may be described as follows, for example.

As illustrated in fig. 5a and 5b, even in scenario 2), the available power in the NR link and the LTE link may be allocated first. The transmission power allocated to the NR link may be reallocated to the NR Uu and the NR side link, and in this case, the transmission power of the NR Uu may be regarded as zero. Therefore, the transmission power allocated to the NR link can be allocated entirely to the NR-side link. Meanwhile, the transmission power allocated to the LTE link may be reallocated to the LTE Uu and LTE sidelink by using one of the methods described in fig. 5a and 5 b.

Fig. 6a and 6b are other examples of allocating transmit power of a V2X UE according to embodiments of the present disclosure.

In fig. 6a and 6b, P _ Uu may represent the maximum transmission power available for Uu transmission, and P _ Side may represent the maximum transmission power available for sidelink transmission. In addition, P3 may indicate the transmission power actually used for Uu transmission, and P4 may indicate the transmission power actually used for sidelink transmission. Since the actually used transmission power cannot be greater than the maximum transmission power allowed, P3 ≦ P _ Uu and P4 ≦ P _ Side should be true in FIG. 6a and FIG. 6 b. Further, P _ Total shown in fig. 6a and 6b is a maximum transmission power value that allows simultaneous transmission of Uu and sidelink. Here, P _ Uu, P _ Side, P3, P4, and P _ Total have linear values not in dB or dBm.

Fig. 6a shows the case where the sum of P _ Uu and P _ Side is less than P _ Total, and fig. 6b shows the case where the sum of P _ Uu and P _ Side is greater than P _ Total. The case where the sum of P _ Uu and P _ Side is equal to P _ Total is not shown in fig. 6a and 6b, but it may be included in the category of fig. 6 a. Further, fig. 6a shows P _ Uu __ P _ Side, while fig. 6b shows P _ Uu > P _ Side. However, this is only an example, and the method described in the present disclosure can be applied even in the case of P _ Uu < P _ Side. In fig. 6a and 6b, Uu transmission may refer to simultaneous transmission of NR Uu and LTE Uu, or transmission by one of NR Uu and LTE Uu. Further, the sidelink transmission may refer to simultaneous transmission of the NR-side link and the LTE-side link, or transmission through one of the NR-side link and the LTE-side link.

After the RRC connection (RRC connected mode) with the base station is completed, the NR V2X UE may configure information on P _ Uu _ dBm, P _ Side _ dBm, and P _ Total _ dBm (here, P _ Uu _ dBm is 10log10(P _ NR), P _ Side _ dBm is 10log10(P _ LTE), and P _ Total _ dBm is 10log10(P _ Total)) through UE-specific RRC parameters. For example, when a V2X UE establishes an RRC connection with an NR base station (gNB), the V2X UE may receive corresponding information from the gNB. When the V2X UE establishes an RRC connection with an LTE base station (eNB), the V2X UE may receive information about P _ Uu _ dBm, P _ Side _ dBm, and P _ Total _ dBm from the eNB. As another example, when the V2X UE establishes an RRC connection with both the gNB and the eNB, it may receive information about P _ Uu _ dBm, P _ Side _ dBm, and P _ Total _ dBm from the primary node. More specifically, the above case may be considered as a Dual Connectivity (DC) scenario, and in an LTE-NR DC environment in which the eNB serves as a primary node, the eNB may configure corresponding information as RRC parameters to the NR V2X UE. In addition, in an NR-LTE DC environment where the gNB serves as a primary node, the gNB may configure corresponding information as an RRC parameter to the NR V2X UE.

On the other hand, P _ Uu _ dBm, P _ Side _ dBm, and P _ Total _ dBm may be configured from a base station (gNB or eNB) where the V2X UE is located through system information (system information block, SIB) instead of UE-specific RRC configuration. Here, the V2X UE may be in a state of not having RRC connection establishment with the base station with which it is camped (i.e., RRC idle state).

From the perspective of the base station, when there is an interface between the gNB and the eNB, the gNB and the eNB may negotiate to set P _ Uu and P _ Side values through the interface. In this case, the sum of P _ Uu and P _ Side may be set to be less than or equal to P _ Total. However, when there is no interface between the gNB and eNB, the gNB and eNB may set the P _ Uu and P _ Side values independently without negotiating the P _ Uu, P _ Side P _ NR, and P _ Total values. Therefore, it may happen that the sum of P _ Uu and P _ Side is greater than P _ Total (P _ Uu + P _ Side > P _ Total) at a particular time.

On the other hand, from the viewpoint of the NR V2X UE, when there is an interface between the Uu support modem and the sidelink support modem, the Uu support modem and the sidelink support modem can exchange information about P1 and P2. In this case, even if the base station performs the configuration so that P _ Uu + P _ Side > P _ Total in the above example is established, by the exchange of the transmission power value information between the Uu support modem and the Side link support modem, the NR V2X UE can adjust the transmission power value so that the sum of P3 and P4 is less than or equal to P _ Total (P3+ P4 ≦ P _ Total). UEs with this capability may be identified as UEs capable of dynamic power allocation between NR and LTE. On the contrary, when there is no interface between the Uu-supported modem and the sidelink-supported modem, information about P3 and P4 cannot be exchanged. In this case, if the base station performs configuration such that P _ Uu + P _ Side > P _ Total in the above example is established, it may be necessary to transmit using only one of the Uu link and the sidelink.

Next, a detailed description will be made of a transmission power allocation operation according to the capability of the UE in various scenario environments exemplified above.

NR V2X UEs that do not have the capability to perform synchronous transmission over Uu and sidelink cannot perform synchronous transmission over Uu and sidelink. Therefore, such a UE can transmit using only one of Uu and sidelink. In this case, as to which link should be used for transmission, one of the following methods may be used.

The NR V2X UE may perform transmission using only one link according to a preset rule. For example, according to the priority of a physical channel transmitted through each link, transmission on a link through which a channel with a low priority is transmitted may be abandoned, and transmission may be performed only on a link through which a channel with a high priority is transmitted. For example, a control channel may have a higher priority than a data channel. That is, when the control channel is transmitted through Uu and the data channel is transmitted through the sidelink, the transmission may be performed only through Uu through which the control channel is transmitted. On the other hand, there may be a case in which the control channel is transmitted through Uu and a sidelink. In this case, the priority set in advance for each channel may be followed. Specific examples of this aspect will be described in detail later.

As another example, the NR V2X UE may perform transmission over only one link according to the priority provided by the base station through RRC configuration. More specifically, the gNB or eNB may configure the priority value for the NR V2X UE through RRC parameters according to the type of data transmitted through Uu and sidelink. Based on the configured priority values, the NR V2X UE may abandon transmissions on the link that is transmitting low priority data and may only perform transmissions on the link that should be transmitting high priority data.

The NR V2X UE capable of performing synchronous transmission on Uu and the side link may perform the following operations according to the setting of the base station.

-when P _ Uu + P _ Side ≦ P _ Total is set by the base station

The NR V2X UE may perform simultaneous transmission of the Uu link and the sidelink by setting the transmission power of the Uu link and the sidelink to P3 and P4, respectively. Here, the base station may perform configuration such that P3 ≦ P _ Uu and P4P _ Side ≦ hold.

-when P _ Uu + P _ Side > P _ Tota is set by the base station

NR V2X UE with dynamic power allocation capability may adjust the transmit power value such that P _ Uu + P _ Side ≦ P _ Total is true, and one of the following methods may be applied.

NR V2X UEs may adjust the transmit power values of Uu and sidelink. More specifically, the transmission power value of Uu may be decreased by w3 × P _ Uu, and the transmission power value of sidelink may be decreased by w4 × P _ Side. Here, w3 × P _ Uu + w4 × P _ Side ≦ P _ Total should be satisfied. w3 and w4 represent the scale factors of Uu and sidelink, respectively, and may have values between 0 and 1. The NR V2X UE can adjust the transmission power value by determining w3 and w4 values satisfying the conditions 0. ltoreq. w 3. ltoreq.1 and 0. ltoreq. w 4. ltoreq.1. As another example, the NR V2X UE may adjust the transmit power value by determining w3 and w4 values that satisfy the condition 0 ≦ w3+ w4 ≦ 1, where w3+ w4 has a value between 0 and 1.

NR V2X UE may reduce the transmit power value of the sidelink without changing the transmit power value of Uu. This may mean a variation of the above example where w4 is always set to 1. Here, w3 may have a value between 0 and 1. As another variation of the above example, a scenario may be considered in which w3 is always set to 1 and the value of w4 is between 0 and 1.

As another example, according to the priority of the physical channel transmitted through each link, a case where a channel of low priority has a lower transmission power value than a channel of high priority may be considered. For example, assuming that the control channel has a higher priority than the data channel, the scale factor for the control channel may be defined as α and the scale factor for the data channel may be defined as β. Here, the α value may always be larger than the β value. Therefore, when the control channel is transmitted through Uu and the data channel is transmitted through sidelink, the transmission power value may be adjusted so that α × P _ Uu + β × P _ Side ≦ P _ Total is established. Conversely, when the control channel is transmitted through the sidelink and the data channel is transmitted through the Uu, the transmission power value may be adjusted so that β × P _ Uu + α × P _ Side ≦ P _ Total is established. On the other hand, there may be a case where both Uu and sidelink transmit a control channel or both transmit a data channel. In this case, the priority set in advance for each channel may be followed. Detailed examples of this will be described later.

Meanwhile, for the NR V2X UE without dynamic power allocation capability, since information on transmission power allocation cannot be exchanged between the Uu supporting modem and the sidelink supporting modem of the UE, the transmission power value cannot be adjusted so that P _ Uu + P _ Side ≦ P _ Total holds. Therefore, the transmission power value can be set by applying at least one of the above-described methods of transmitting using only one link.

In the above example, the method of allocating the transmission power to Uu and the side link has been described. However, Uu may be composed of NR Uu and LTE Uu, and the side link may be composed of NR side link and LTE side link. Therefore, it may be necessary to reallocate the transmission power that has been allocated to the Uu and the sidelink to the NR link and the LTE link. One of the following methods can be regarded as a method of transmission power reallocation.

[ method of allocating transmission power to NR Uu and LTE Uu ].

The transmission power allocated to Uu may be reallocated to NR Uu and LTE Uu by employing at least one of the following methods.

-method 1: allocating transmission power according to predetermined priority

The transmit power may be assigned to the NR Uu and the LTE Uu according to a predetermined priority. Here, it may be defined in advance such that all physical layer channels transmitted through the NR Uu have higher priority than all physical layer channels transmitted through the LTE Uu. Conversely, it may be defined in advance such that all physical layer channels transmitted through the LTE Uu have higher priority than all physical layer channels transmitted through the NR Uu.

As another illustration, the priority may be determined according to the type of physical layer channel transmitted through the NR Uu and the LTE Uu. That is, according to the priority of the physical channel transmitted through each Uu, transmission of Uu through which a channel having a low priority is transmitted may be abandoned, and transmission may be performed only on Uu through which a channel having a high priority is transmitted. For example, when the PRACH is transmitted through the NR Uu and at the same time a physical channel other than the PRACH (e.g., PUCCH or PUSCH) is transmitted through the LTE Uu, the UE may abandon the LTE Uu transmission and perform the NR Uu transmission (i.e., transmission power allocated to Uu is allocated such that the transmission power of the LTE Uu is set to 0 and the remaining transmission power is used for the NR Uu transmission). On the contrary, when a physical channel other than the PRACH is transmitted through the NR Uu and at the same time the PRACH is transmitted through the LTE Uu, the UE may abandon the NR Uu transmission and perform the LTE Uu transmission (i.e., transmission power allocated to Uu is allocated such that the transmission power of the NR Uu is set to 0 and the remaining transmission power is used for the LTE Uu transmission). For the case where physical layer channels other than PRACH are transmitted by NR Uu and LTE Uu, the following method may be adopted as the priority.

Control channels may have higher priority than data channels. For example, PRACH > PUCCH with HARQ-ACK and/or SR (scheduling request) > PUCCH with CSI or PUSCH with CSI > PUSCH > SRs.

As another example, unlike the above example where the transmission power is set to 0, the transmission power of NR Uu or LTE Uu may be reduced such that the sum of the transmission power for Uu transmission is less than or equal to the maximum transmission power (Pcmax) of the UE. Here, the transmission power of the LTE Uu may be reduced while maintaining the transmission power of the NR Uu (without reducing the transmission power), or the transmission power of the NR Uu may be reduced while maintaining the transmission power of the LTE Uu.

-method 2: allocating transmit power according to configured priority

The base station (eNB or gNB) may configure priorities of NR Uu and LTE Uu to the UE through System Information (SIB) or UE-specific RRC configuration. The UE may abandon transmission over Uu having a low priority and perform transmission over Uu having a high priority (i.e., transmission power allocated to Uu is allocated such that transmission power of Uu having a low priority is set to 0 and the remaining transmission power is used for transmission over Uu having a high priority).

As another example, the UE may adjust the transmission power for transmission through Uu having a high priority by γ 1, and adjust the transmission power for transmission through Uu having a low priority by δ 1. Here, γ 1 and δ 1 are parameters for adjusting Uu transmission power, and may each have a value between 0 and 1. In addition, γ 1 < δ 1.

As another variation of the above example, the UE may adjust the transmit power for transmission over Uu having a low priority while maintaining the transmit power for transmission over Uu having a high priority. This can be seen as the case where γ 1 is always fixed to 1 and δ 1 is used. That is, the transmission power of Uu having a low priority may be reduced by δ 1 so that the sum of the transmission power for NR Uu transmission and the transmission power for LTE Uu transmission is less than or equal to the maximum transmission power (Pcmax) of the UE.

[ method for allocating transmission power to NR-side link and LTE-side link ].

The transmission power allocated to the sidelink may be reallocated to the NR side link and the LTE side link by employing at least one of the following methods.

-method 1: the transmission power is allocated according to a predetermined priority-the transmission power may be allocated to the NR side link and the LTE side link according to a predetermined priority. More specifically, among channels transmitted through each sidelink, it is possible to adjust the transmission power of a channel having a low priority while maintaining the transmission power of a channel having a high priority. Here, the transmission power of the low priority channel may be reduced such that the sum of the transmission power for NR-side link transmission and the transmission power for LTE-side link transmission is less than or equal to the maximum transmission power (Pcmax) of the UE. There are various methods to define the priority, and at least one of the following methods may be used.

LTE side-link transmission may always have a higher priority than NR side-link transmission. In this case, the V2X UE may set the NR side link transmission power to 0 (drop or discard side link transmission) and perform LTE side link transmission (i.e., the transmission power allocated to the side link is allocated such that the transmission power of the NR side link is set to 0 and the remaining transmission power is used for LTE side link transmission). Conversely, it may be predefined that the priority of NR side link transmission is always higher than that of LTE side link transmission.

Priority may be determined according to the type of physical layer channel transmitted through the NR side link and the LTE side link. For example, when an NR sidelink synchronization channel (sidelink synchronization signal block, S-SSB) is transmitted through an NR sidelink, the UE may abandon LTE sidelink transmission and perform S-SSB transmission through the NR sidelink. In contrast, when an LTE sidelink synchronization signal (sidelink synchronization signal, SLSS) and a physical layer broadcast channel (physical sidelink broadcast channel, PSBCH) are transmitted through an LTE sidelink, the UE may give up the NR sidelink transmission and perform the SLSS and PSBCH transmission through the LTE sidelink. This may mean that the physical layer synchronization channel always has a high priority. For the remaining physical layers, the UE may randomly set the priority.

As another example of determining the priority according to the type of physical layer channel transmitted through Uu and sidelink, the priority may be defined by one of the following methods according to the type of physical layer channel and signal transmitted through sidelink.

Example 1: the control channel may have a higher priority than the data channel. For example, synchronization channel > PSCCH > PSFCH with HARQ-ACK or PSFCH with CSI > psch with HARQ-ACK or PSCCH > psch with CSI > S-CSI-RS.

Example 2: the priority may be determined according to the type of control information transmitted through the physical layer channel (e.g., HARQ-ACK information may have a higher priority than CSI information). More specifically, synchronization channel > PSCCH > PSFCH with HARQ-ACK or PSCCH with HARQ-ACK > PSFCH with CSI or PSCCH > S-CSI-RS with CSI.

In the above example, the PSCCH and S-CSI-RS may have no priority (i.e., may not be considered priority or have the lowest priority), while the case of transmitting HARQ-ACK and the case of transmitting CSI may have the same priority. In addition, the channel through which the feedback information is transmitted may have a higher priority than the synchronization channel.

-method 2: allocating transmit power according to configured priority

The NR V2X UE may transmit Sidelink Control Information (SCI) over the PSCCH for controlling its transmission of the psch, PSFCH or S-CSI-RS transmitted over the NR sidelink. Here, the NR V2X UE may receive priority information for transmission of a PSSCH, a PSFCH, or an S-CSI-RS to be transmitted by it through an NR side link from a higher layer (e.g., an application layer). The priority information may be composed of N bits and may be included in the SCI. For example, if the priority information is composed of 3 bits, 000 indicates a priority "0", and 111 indicates a priority "7", so it can be seen that there is a total of 8 priorities. Here, a smaller value may be prioritized. Likewise, the NR V2X UE may transmit SCI over the PSCCH, which is used to control the transmission of the psch to be transmitted by it over the LTE sidelink. Here, the NR V2X UE may receive priority information of the pschs to be transmitted by it through the LTE sidelink from a higher layer (e.g., an application layer). Accordingly, the NR V2X UE may compare priority information included in SCI for NR side link transmission and priority information included in SCI for LTE side link transmission, and may perform high-priority side link transmission (i.e., transmission power allocated to a sidelink is allocated such that transmission power of a sidelink having a low priority is set to 0 and the remaining transmission power is used for transmission through a side link having a high priority).

As another example, the UE may adjust the transmit power for transmission over the sidelink with low priority while maintaining the transmit power for transmission over the sidelink with high priority. Here, the transmission power for transmission through the low-priority sidelink may be reduced such that the sum of the transmission power for transmission through the high-priority sidelink and the transmission power for transmission through the low-priority sidelink is less than or equal to the maximum transmission power (Pcmax) of the UE.

Fig. 6a and 6b may be applied to the case where "scenario 3) mentioned in fig. 4 is transmitted using four links simultaneously (NR Uu + NR side link + LTE Uu + LTE side link)". However, since the scene 3) includes the scene 1) and the scene 2), the above description is not limited to the scene 3), and can be extended to the scene 1) and the scene 2). For example, to explain how the transmission power allocation method of scenario 3) is applied to scenario 2), the transmission power allocation method of simultaneously transmitting "NR-side link + LTE Uu" in scenario 2) may be described as follows, for example.

As described in fig. 6a and 6b, even in scenario 2), the available power in Uu and sidelink may be allocated first. The transmission power allocated to Uu may be reallocated to NR Uu and LTE Uu, and the transmission power allocated to the sidelink may be reallocated to NR sidelink and LTE sidelink. Here, the transmission power of NR Uu may be regarded as zero in scenario 2). Therefore, the transmission power allocated to Uu may be allocated entirely to LTE Uu. Meanwhile, by using one of the methods described in fig. 6a and 6b, the transmission power allocated to the sidelink can be reallocated to the NR sidelink and the LTE sidelink.

Meanwhile, although not mentioned in the present disclosure, any combination of the methods described in fig. 5a and 5b and fig. 6a and 6b is possible. For example, the transmission power of the NR link and the LTE link may be allocated to P _ NR and P _ LTE as described in fig. 5a and 5B, and in the NR link, the transmission power allocation between the NR Uu and the NR Side link and the transmission power allocation between the LTE Uu and the LTE Side link may be performed by a method using P _ Uu and P _ Side described in fig. 6a and 6B.

As another example, transmission power of Uu and sidelink may be allocated to P _ Uu and P _ Side described in fig. 6a and 6b, and in the Uu link, transmission power allocation between NR Uu and LTE Uu and transmission power allocation between NR sidelink and LTE sidelink may be performed by using the method of P _ NR and P _ LTE described in fig. 5a and 5 b.

Fig. 7 is a diagram illustrating a structure of a UE according to an embodiment of the present disclosure.

Referring to fig. 7, the UE may include a transceiver 701, a UE controller 701, and a memory 701. In the present disclosure, the UE controller 702 may be defined as a circuit, an application-specific integrated circuit, or at least one processor.

Transceiver 701 may send and receive signals to another network entity. The transceiver 701 may perform communication by exchanging signals with, for example, a base station and/or a different UE. The UE controller 702 may control the overall operation of the UE according to embodiments presented in this disclosure. For example, the UE controller 701 may control the signal flow between blocks to perform operations according to the diagrams and flowcharts described above.

The memory 703 may store at least one of information transmitted and received by the transceiver 701 or information generated by the UE controller 702.

Fig. 8 is a diagram illustrating a structure of a base station according to an embodiment of the present disclosure.

Referring to fig. 8, a base station may include a transceiver 801, a base station controller 802, and a memory 803. In the present disclosure, base station controller 802 may be defined as a circuit, an application specific integrated circuit, or at least one processor.

The transceiver 801 may send and receive signals to another network entity. The transceiver 801 may perform communication by exchanging signals with, for example, a UE and/or a different network entity, another base station. The base station controller 802 may control the overall operation of the base station in accordance with embodiments set forth in this disclosure. For example, the base station controller 802 may control the flow of signals between blocks to perform operations in accordance with the above-described diagrams and flowcharts.

The memory 803 may store at least one of information transmitted and received through the transceiver 801 or information generated through the base station controller 802.

The above-described embodiments disclosed in the present specification and drawings are only intended as specific examples to facilitate the understanding of the present disclosure, and are not intended to limit the scope of the present disclosure. Therefore, it is to be understood that all changes and modifications except the embodiments disclosed in the disclosure are to be included within the scope of the disclosure.