Method and apparatus for enabling multiple systems to share frequency resources in next generation mobile communication

Abstract

The present disclosure relates to a 5G or 6G communication system capable of increasing the data transmission rate and maximizing the frequency efficiency. More specifically, the present disclosure provides a method performed by a first base station associated with a first RAT in a wireless communication system. The method comprises the steps of: receiving, from a second base station associated with a second RAT, information regarding a first radio resource used for frequency spectrum sharing with the first RAT and the second RAT, the information regarding the first radio resource including information regarding a second radio resource to be used by the second base station among the first radio resource, and information regarding an SCS applied to the second radio resource; transmitting, to a terminal, configuration information including the information regarding the first radio resource; and receiving, from the terminal, data on the basis of a valid radio resource from which the second radio resource is excluded from radio resources scheduled on the basis of the SCS.

Description

Method and device for sharing frequency resources by multiple systems in next-generation mobile communications

[0001] The present disclosure relates to the operation of a terminal and a base station in a wireless communication system (or mobile communication system). Specifically, the present disclosure relates to a method for sharing frequency resources between heterogeneous wireless communication systems.

[0002] 5G mobile communication technology defines a wide frequency band to enable fast transmission speeds and new services, and can be implemented not only in the sub-6GHz band ('Sub 6GHz'), such as 3.5 gigahertz (3.5GHz), but also in the ultra-high frequency band ('Above 6GHz'), also known as millimeter wave (mmWave), such as 28GHz and 39GHz. Furthermore, for 6G mobile communication technology, which is called the system after 5G communication (Beyond 5G), it is expected that it will be very important to secure new frequency resources, such as the sub-6GHz band, ultra-high frequency bands, and the upper mid band (7-24GHz), to handle the rapidly increasing data traffic due to the spread of artificial intelligence (AI) technology and the increase in streaming services and to improve user experience. It is expected that it will become very important to secure new frequency resources, such as the mid-frequency band (7-24GHz), also called the upper mid band, and to utilize all available frequency resources efficiently as needed. To this end, reallocating, reusing, or sharing existing frequency bands from 2G to 5G for 6G may be considered. Separately, since the introduction of 5G, the communications market has seen a growing focus on system operational efficiency, sustainability, and improved user experience. Consequently, in addition to improving traditional communication performance, such as data transmission speed and latency, the adoption of new innovative technologies like AI, operational cost reduction, energy efficiency improvements, expanded service coverage, and the introduction of new services are becoming increasingly important.

[0003] In the early stages of 5G mobile communication technology, the goal is to support services and meet performance requirements for enhanced mobile broadband (eMBB), ultra-reliable low-latency communications (URLLC), and massive machine-type communications (mMTC). These include beamforming and massive MIMO to mitigate path loss of radio waves in ultra-high frequency bands and increase radio transmission distances, support for various numerologies (such as operation of multiple subcarrier intervals) and dynamic operation of slot formats for efficient use of ultra-high frequency resources, initial access technology to support multi-beam transmission and wideband, definition and operation of BWP (band-width part), new channel coding methods such as LDPC (low density parity check) codes for large-capacity data transmission and polar codes for reliable transmission of control information, L2 pre-processing, and networks that provide dedicated networks specialized for specific services. Standardization of slicing (network slicing) etc. has been progressing.

[0004] Since the early days of 5G mobile communication technology, discussions have been held on improving and enhancing the initial 5G mobile communication technology in consideration of the services that 5G mobile communication technology was intended to support, including V2X (vehicle-to-everything) to help autonomous vehicles make driving decisions based on their own location and status information transmitted by the vehicle and to increase user convenience, NR-U (new radio unlicensed) for the purpose of system operation that meets various regulatory requirements in unlicensed bands, NR terminal low power consumption technology (UE power saving), non-terrestrial network (NTN), which is direct terminal-satellite communication to secure coverage in areas where communication with terrestrial networks is impossible, positioning, NR support up to 77 Hz (supporting NR operation to 71 GHz), support of reduced capability NR devices for lower cost and complexity compared to general terminals, UE power saving enhancement for improved power management in preparation for the use of various terminal types, and sidelink. Evolution of duplexing technology (duplex enhancements) that researches a new type of duplexing called subband non-overlapping full duplex (SBFD), sidelink enhancement, network energy saving that secures the idle period in which the base station operates in maximum power saving mode and reduces power consumption.Physical layer standardization has been carried out for technologies such as network controlled repeaters, which have improved performance compared to existing repeaters by having the ability to receive and process side control information from the network.

[0005] In addition, it supports new services through linkage and convergence with other industries, including the Industrial Internet of Things (IIoT), an intelligent factory, IAB (Integrated Access and Backhaul) that provides nodes for expanding network service areas by integrating wireless backhaul links and access links, Mobility Enhancement technology including Conditional Handover and Dual Active Protocol Stack (DAPS) handover, 2-step RACH for NR that simplifies random access procedures, multicast and broadcast, standardization of support for multi USIM devices that provide services to users using information from two or more subscriber identity modules (SIMs), sidelink relay that provides relay-related functions to support connections between terminals in long distances and between terminals and networks, small data transmission (SDT) that transmits small data or signaling in an inactive state without transitioning to a connected state, and lower layer triggered mobility (L1 / L2 triggered mobility, LTM) / continuous Standardization of the radio interface architecture / protocol layer for technologies such as mobility enhancements including subsequent conditional PScell ​​addition / change (SCPAC) / conditional handover with candidate SCGs, and extended reality support (XR enhancement) to support XR services in NR systems has also been progressing.5G baseline architecture for integrating network functions virtualization (NFV) and software-defined networking (SDN) technologies (e.g., service-based architecture, service-based interface), mobile edge computing (MEC) that provides services based on the location of the terminal, non-public networks (NPN) that can be used only by some permitted terminals for non-public purposes, disaster roaming that supports the use of communication services through other carrier networks in the event of a communication disaster, proximity-based service via 5G system, support of UAS to support remote identification, tracking, and authorization of uncrewed aerial vehicles (UAVs), structural enhancements to support XR and interactive media services, 5GS to support AI / ML (artificial intelligence / machine learning) services, and advanced mobile edge computing that provides edge computing services in a roaming network. Standardization of system architecture / service fields for the back has also been carried out.

[0006] Currently, at the physical layer, standardization is in progress for technologies such as beam prediction using AI / ML technology, CSI (channel state information) prediction to improve positioning accuracy, ultra-low power terminal technology using low-power wake-up receivers, technology for transmitting LTE (long term evolution) broadcasts to 5G networks, MIMO transmission technology using multiple base stations, and ultra-low power terminals (ambient IoT) that transmit data by obtaining power from an external source without a battery. At the radio interface architecture / protocol layer, standardization is in progress for technologies such as support for LTM scenarios and conditional LTM between Central Units (CUs), support for the same XR service simultaneously between multiple devices, NTN coverage enhancement and evolution, AI / ML-based mobility support, and terminal-to-terminal connection relay across multiple hops between terminals and the network. Furthermore, standardization is underway for satellite communication optimization, energy management and efficiency improvement of 5G systems, SBI-based user plane evolution, Ambient IoT technology, data service provision methods over the IP multimedia subsystem (IMS), and system architecture / service standardization for avatar communication services. Once these 5G mobile communication systems are commercialized, an explosive increase in connected devices will be connected to the communication network, necessitating enhanced functionality and performance of 5G mobile communication systems and integrated operation of these connected devices.To this end, additional new research will be conducted on eXtended Reality (XR), AI / ML-based 5G performance improvement and complexity reduction, AI service support, metaverse service support, drone communications, etc. to efficiently support augmented reality (AR), virtual reality (VR), and mixed reality (MR).

[0007] Furthermore, the advancement of 5G mobile communication systems is expected to enhance 5G performance and ultimately serve as the foundation for its evolution to 6G. In the 6G era, the three major 5G services mentioned above—eMBB, URLLC, and mMTC—are expected to evolve and expand into immersive communication (IC), hyper-reliable and low-latency communication (HRLLC), and massive communication (MC) services, respectively. In addition, new services such as artificial intelligence (AI) and communication, integrated sensing and communication, and ubiquitous connectivity will be additionally supported. To meet these diverse 6G services, improved performance requirements compared to 5G are essential, and standardization to define these requirements is currently underway.

[0008] In this way, to meet the expanded services and enhanced performance requirements of 6G, it is expected that not only will it be essential to improve existing communication performance, but also to optimize and streamline system operation through the introduction of AI technology, improved energy efficiency, expanded coverage, and application of next-generation security technologies, as well as the development of sustainable communication technologies.

[0009] To this end, the latest AI technology is applied to all areas from the communication system design stage to development, management, and operation to improve communication performance and realize network automation and efficiency; AI-embedded technology to improve user-perceived performance and network operation efficiency by improving power consumption of networks and terminals; technology to reduce power consumption in core base station components such as RF (radio frequency) and modems and in the process of channel coding and signal modulation and demodulation transmission and reception; multi-antenna transmission technology (eXtreme MIMO, X-MIMO) that utilizes large-scale antennas to overcome propagation path loss due to high frequency compared to the 3.5 GHz band of 5G communication and provide equivalent coverage; multiple base station-based transmission and reception technology (distributed MIMO, D-MIMO) to improve quality in cell edge areas; full-duplex communication (sub-band non-overlapping full duplex, SBFD) technology to improve frequency efficiency and system network; next-generation encryption technology (post quantum cryptography, PQC) and zero trust architecture (ZTA) technology to strengthen 6G communication security; initial access delay and mobility Research will be focused on technologies to minimize delay, designing a hardware-friendly protocol structure for ultra-high-speed data processing, and expanding the application of integrity protection technologies.

[0010] In addition, research will be conducted on the structure of mobile communication systems (preventing redundant functions, simplifying functions, etc.), introducing new planes for providing service providers, protecting user privacy, realistic services, enhancing network resiliency, network sharing technologies, improved security technologies (false base stations, lower layer protection, etc.), and intent-based network operation and management.

[0011] Next-generation mobile communication system 6G (6 th 6G (New Generation) systems are expected to provide data services to users by exclusively utilizing some frequency bands used by existing mobile communication systems, such as NR and LTE. However, this will reduce the frequency resources available to existing mobile communication systems, potentially leading to a shortage of radio resources in existing systems. To address this, discussions are underway on Multi-RAT Spectrum Sharing (MRSS), which would allow frequencies used by existing mobile communication systems to be shared with 6G systems.

[0012] Accordingly, one purpose of the present disclosure is to provide a method and device for sharing frequency resources in a plurality of heterogeneous communication systems.

[0013] In addition, one purpose of the present disclosure is to propose a method for sharing radio resources of a frequency band (multi-rat spectrum sharing, MRSS) when a 6G system shares the same frequency band with an NR (or LTE) system.

[0014] In addition, one purpose of the present disclosure is to provide a specific method for utilizing a reference signal (RS) of an NR (or LTE) system for 6G operation (e.g., communication operation with a 6G base station) as the 6G system shares radio resources with the NR (or LTE) system.

[0015] The technical problems to be achieved in various embodiments of the present disclosure are not limited to those mentioned above, and other technical problems not mentioned can be considered by a person having ordinary skill in the art from the various embodiments of the present disclosure described below.

[0016] In order to solve the above problem, one embodiment of the present disclosure discloses a method performed by a first base station associated with a first radio access technology (RAT) in a wireless communication system. The method includes the steps of: receiving, from a second base station associated with a second RAT, information about a first radio resource used for sharing a frequency spectrum with the first RAT and the second RAT, wherein the information about the first radio resource includes information about a second radio resource to be used by the second base station among the first radio resources and information about a subcarrier spacing (SCS) applied to the second radio resource; transmitting, to a terminal, configuration information including the information about the first radio resource; and receiving, from the terminal, data based on valid radio resources from which the second radio resource is excluded among radio resources scheduled based on the SCS.

[0017] One embodiment of the present disclosure discloses a method performed by a terminal in a wireless communication system. The method comprises the steps of: receiving, from a first base station associated with a first RAT, configuration information including information on a first radio resource used for frequency spectrum sharing between the first RAT and a second RAT, wherein the information on the first radio resource includes information on a second radio resource to be used by a second base station associated with the second RAT among the first radio resources and information on a subcarrier spacing (SCS) applied to the second radio resource; and transmitting data to the first base station based on valid radio resources from which the second radio resource is excluded among radio resources scheduled based on the SCS; wherein the information on the first radio resource is transmitted from the second base station to the first base station.

[0018] One embodiment of the present disclosure discloses a first base station associated with a first radio access technology (RAT) in a wireless communication system. The first base station comprises: at least one transceiver; at least one processor communicatively connected to the at least one transceiver; And a memory communicatively connected to the at least one processor and executable by the at least one processor, the memory storing instructions that cause the first base station to receive, from a second base station associated with a second RAT, information about a first radio resource used for frequency spectrum sharing with the first RAT and the second RAT, wherein the information about the first radio resource includes information about a second radio resource to be used by the second base station among the first radio resources and information about a subcarrier spacing (SCS) applied to the second radio resource, transmit configuration information including the information about the first radio resource to a terminal, and receive data from the terminal based on valid radio resources from which the second radio resource is excluded among radio resources scheduled based on the SCS.

[0019] One embodiment of the present disclosure discloses a terminal in a wireless communication system. The terminal comprises: at least one transceiver; at least one processor communicatively connected to the at least one transceiver; And a memory communicatively connected to the at least one processor and executable by the at least one processor, wherein the terminal receives, from a first base station associated with a first RAT, configuration information including information on a first radio resource used for frequency spectrum sharing with the first RAT and a second RAT, wherein the information on the first radio resource includes information on a second radio resource to be used by a second base station associated with the second RAT among the first radio resources and information on a subcarrier spacing (SCS) applied to the second radio resource, and stores an instruction that causes the first base station to transmit data based on a valid radio resource from which the second radio resource is excluded among radio resources scheduled based on the SCS; wherein the information on the first radio resource is transmitted from the second base station to the first base station.

[0020] The various embodiments of the present disclosure described above are only some of the preferred embodiments of the present disclosure, and various embodiments reflecting the technical features of the various embodiments of the present disclosure can be derived and understood by a person having ordinary skill in the art based on the detailed description to be described below.

[0021] According to one example of the present disclosure, the 6G system uses wireless resources not used by the existing NR (or LTE) system for communication between the terminal and the 6G system, thereby increasing the efficiency of resource use and improving the throughput of the 6G service.

[0022] In addition, according to one example of the present disclosure, by using the reference signal (RS) of the existing NR (or LTE) system for the 6G operation of the 6G system, there is an effect of saving power consumed by the 6G base station for transmitting the RS of a separate 6G system.

[0023] The effects that can be obtained from various embodiments of the present disclosure are not limited to the effects mentioned above, and other effects not mentioned can be clearly derived and understood by a person having ordinary skill in the art based on the detailed description below.

[0024] FIG. 1 is a diagram illustrating the structure of a next-generation mobile communication system according to an embodiment of the present disclosure.

[0025] Figure 2 illustrates an embodiment of NR (New Radio) and 6G (6 th This diagram illustrates a case where the generation) system shares the frequency spectrum.

[0026] FIG. 3 is a flowchart of a procedure for sharing a frequency spectrum between NR and 6G systems according to one embodiment of the present disclosure.

[0027] FIG. 4 is a diagram illustrating how NR and 6G systems share a frequency spectrum according to one embodiment of the present disclosure.

[0028] FIG. 5 is a flowchart illustrating terminal operation when NR and 6G systems share a frequency spectrum according to an embodiment of the present disclosure.

[0029] FIG. 6 is a flowchart illustrating the operation of a 6G base station when NR and a 6G system share a frequency spectrum according to an embodiment of the present disclosure.

[0030] FIG. 7 is a diagram illustrating a case where a 6G system according to one embodiment of the present disclosure shares an LTE or NR frequency spectrum.

[0031] FIG. 8 is a diagram illustrating the proportion of wireless resources occupied by NR reference signals according to one embodiment of the present disclosure.

[0032] FIG. 9 is a diagram illustrating a co-located 6G-NR or co-located 6G-LTE scenario according to one embodiment of the present disclosure.

[0033] FIG. 10 is a flowchart of a procedure for using an NR reference signal for 6G operation in a co-located 6G-NR or co-located 6G-LTE scenario according to one embodiment of the present disclosure.

[0034] FIG. 11 is a flowchart of a terminal operation using an NR reference signal for 6G operation in a co-located 6G-NR or co-located 6G-LTE scenario according to an embodiment of the present disclosure.

[0035] FIG. 12 is a flowchart of a 6G base station operation using an NR reference signal for 6G operation in a co-located 6G-NR or co-located 6G-LTE scenario according to an embodiment of the present disclosure.

[0036] FIG. 13 is a block diagram illustrating the internal structure of a terminal according to an embodiment of the present disclosure.

[0037] FIG. 14 is a block diagram illustrating the structure of a base station according to one embodiment of the present disclosure.

[0038] In describing embodiments of the present disclosure, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the gist of the present disclosure, the detailed description will be omitted.

[0039] For the same reason, some components in the attached drawings are exaggerated, omitted, or schematically depicted. Furthermore, the dimensions of each component do not entirely reflect its actual size. Identical or corresponding components in each drawing are assigned the same reference numbers.

[0040] The advantages and features of the present disclosure, and methods for achieving them, will become clearer with reference to the embodiments described below in detail together with the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed below and may be implemented in various different forms. These embodiments are provided only to ensure that the disclosure of the present disclosure is complete and to fully inform those skilled in the art of the scope of the disclosure, and the present disclosure is defined only by the scope of the claims. Like reference numerals designate like elements throughout the specification. In addition, when describing the present disclosure, if a specific description of a related function or configuration is determined to unnecessarily obscure the gist of the present disclosure, the detailed description thereof will be omitted. In addition, the terms described below are terms defined in consideration of the functions of the present disclosure, and these may vary depending on the intention or custom of the user or operator. Therefore, their definitions should be made based on the contents throughout the specification.

[0041] The terms used in the following description to identify connection nodes, terms referring to network entities, terms referring to messages, terms referring to interfaces between network entities, and terms referring to various identification information are provided for convenience of explanation. Therefore, the present invention is not limited to the terms described below, and other terms referring to objects with equivalent technical meanings may be used.

[0042] Hereinafter, the base station is an entity that performs resource allocation of the terminal, and may be at least one of a gNode B, an eNode B, a Node B, a BS (Base Station), a wireless access unit, a base station controller, or a node on a network. The terminal may include a UE (User Equipment), an MS (Mobile Station), a cellular phone, a smartphone, a computer, or a multimedia system capable of performing a communication function. In the present disclosure, downlink (DL) refers to a wireless transmission path of a signal transmitted from a base station to a terminal, and uplink (UL) refers to a wireless transmission path of a signal transmitted from a terminal to a base station. In addition, although the LTE or LTE-A system may be described below as an example, the embodiments of the present disclosure may also be applied to other communication systems having similar technical backgrounds or channel types. For example, the 5th generation mobile communication technology (5G, new radio, NR) developed after LTE-A may be included in a system to which the embodiments of the present disclosure may be applied, and 5G below may also be a concept that includes existing LTE, LTE-A, and other similar services. Furthermore, the present disclosure may be applied to other communication systems with some modifications, as determined by a person skilled in the art, without significantly departing from the scope of the present disclosure. It will be appreciated that each block of the flowchart diagrams and combinations of the flowchart diagrams can be implemented by computer program instructions.

[0043] These computer program instructions may be installed in a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus, so that the instructions executed by the processor of the computer or other programmable data processing apparatus create means for performing the functions described in the flowchart block(s). These computer program instructions may also be stored in a computer-available or computer-readable memory that can be directed to a computer or other programmable data processing apparatus to implement functions in a particular manner, so that the instructions stored in the computer-available or computer-readable memory can produce an article of manufacture that includes instruction means for performing the functions described in the flowchart block(s). The computer program instructions may also be installed on a computer or other programmable data processing apparatus, so that a series of operational steps are performed on the computer or other programmable data processing apparatus to create a computer-implemented process, so that the instructions executing on the computer or other programmable data processing apparatus can provide steps for performing the functions described in the flowchart block(s).

[0044] Additionally, each block may represent a module, segment, or portion of code that contains one or more executable instructions for executing a specific logical function(s). It should also be noted that in some alternative implementation examples, the functions mentioned in the blocks may occur out of order. For example, two blocks shown in succession may in fact be executed substantially simultaneously, or the blocks may sometimes be executed in reverse order depending on the corresponding function. In this case, the term '~unit' used in the present embodiment means software or a hardware component such as an FPGA (Field Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit), and the '~unit' may perform certain roles. However, the '~unit' is not limited to software or hardware. The '~unit' may be configured to be on an addressable storage medium and may be configured to execute one or more processors. Thus, as an example, the '~ unit' includes components such as software components, object-oriented software components, class components, and task components, processes, functions, attributes, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functionality provided within the components and '~ units' may be combined into a smaller number of components and '~ units' or further separated into additional components and '~ units'. In addition, the components and '~ units' may be implemented to reproduce one or more CPUs within a device or a secure multimedia card. Also, in an embodiment, the '~ unit' may include one or more processors.

[0045] For convenience of explanation, the present invention uses terms and names defined in the 3rd Generation Partnership Project Long Term Evolution (3GPP) LTE standard. However, the present invention is not limited to these terms and names and can be equally applied to systems conforming to other standards. In the present invention, the term "eNB" may be used interchangeably with "gNB" for convenience of explanation. In other words, a base station described as an eNB may also represent a gNB.

[0046] Hereinafter, an embodiment of the present disclosure will be described with reference to the attached drawings.

[0047] Figure 1 is a diagram illustrating the structure of a next-generation mobile communication system.

[0048] Referring to FIG. 1, as illustrated, a wireless access network of a next-generation mobile communication system (New Radio, NR) is composed of a next-generation base station (New Radio Node B, hereinafter referred to as gNB) (1-10) and an access and mobility management function (AMF) (1-05, New Radio Core Network). A user terminal (New Radio User Equipment, hereinafter referred to as NR UE or terminal) (1-15) accesses an external network through the gNB (1-10) and the AMF (1-05).

[0049] In Figure 1, the gNB corresponds to the eNB (Evolved Node B) of the existing LTE (long term evolution) system. The gNB is connected to the NR UE via a wireless channel and can provide superior services than the existing Node B (1-20). In the next-generation mobile communication system, all user traffic is serviced through a shared channel, so a device that collects status information such as the buffer status of the UEs, available transmission power status, and channel status and performs scheduling is required, and this is handled by the gNB (1-10). A single gNB typically controls multiple cells. In NR, in order to implement ultra-high-speed data transmission compared to the existing LTE, it can have a bandwidth higher than the existing maximum, and beamforming technology can be additionally grafted using the orthogonal frequency division multiplexing (OFDM) method as a wireless access technology. In addition, an adaptive modulation and coding (AMC) method is applied, which determines the modulation scheme and channel coding rate according to the channel status of the terminal.

[0050] AMF (1-05) performs functions such as mobility support, bearer setup, and QoS (quality of service) setup. AMF (1-05) is a device that handles various control functions as well as mobility management functions for terminals and is connected to multiple base stations. In addition, the next-generation mobile communication system can be interoperable with the existing LTE system, and AMF is connected to the mobility management entity (MME) (1-25) through a network interface. MME (1-25) is connected to the existing base station, eNB (1-30). Terminals that support LTE (E-UTRA)-NR Dual Connectivity (EN-DC) can transmit and receive data while maintaining connection to both gNB and eNB (1-35).

[0051] FIG. 2 is a diagram illustrating a case where NR and 6G systems share a frequency spectrum according to one embodiment of the present disclosure.

[0052] The NR system can provide data services to users by using the frequency band 410 to 7125 MHz, referred to as FR1 (Frequency Range 1), and the frequency bands 24250 to 52600 MHz and 52600 to 71000 MHz, referred to as FR2-1 and FR2-2, respectively. The next-generation mobile communication system 6G (6 thThe 6G (Remote Access Generation) system is expected to provide data services to users by exclusively using some frequency bands used by existing mobile communication systems, such as NR and LTE, along with the 7125 to 24250 MHz frequency band, referred to as FR3. Since the frequency band range in FR3 that can be used for 6G systems may not be sufficient until around 2030, using the frequency bands occupied by existing mobile communication systems for 6G systems can be one solution to the frequency shortage problem. However, the frequency exclusive use may conversely cause a shortage of radio resources in existing mobile communication systems. Therefore, an alternative that can efficiently solve this is to use the frequencies used by existing mobile communication systems together with 6G. In this disclosure, this is referred to as Multi-RAT (radio access technology) Spectrum Sharing (MRSS). For example, as in (a) of FIG. 2, among the NR frequency carriers (2-05, 2-10), some NR carriers (2-10) may be shared and used with a 6G carrier (2-15). The 6G carrier (2-15) shared with the NR frequency carrier may be used as a PCell (primary cell) or an SCell (secondary cell) in a CA (carrier aggregation) scenario. In the CA scenario, the 6G carrier (2-15) shared with the NR frequency carrier may be aggregated with a predetermined 6G frequency carrier (2-20). As another example, as in (b) of FIG. 2, a plurality of NR frequency carriers (2-25, 2-30) may be shared and used with one 6G carrier (2-35). The 6G carrier (2-35) shared with the NR frequency carrier may be used as a PCell or an SCell in a CA scenario.In the CA scenario illustrated in (b) of FIG. 2, the 6G carrier (2-35) shared with the NR frequency carriers (2-25, 2-30) can be aggregated with a predetermined 6G frequency carrier (2-40).

[0053] The present disclosure proposes a method for two heterogeneous mobile communication systems to share radio resources of a frequency when the NR frequency carrier and the 6G carrier share a frequency allocated to the NR. The NR base station is characterized in that it provides the 6G base station with information about a predetermined radio resource to be protected or used by itself. In the present disclosure, the radio resource to be protected or used by itself is a radio resource used or allocated to be used by a first base station of a first communication system, and may mean a radio resource included in a frequency domain shared between a second base station of a second communication system and the first base station, but the use of which by the second base station is restricted or needs to be restricted.

[0054] FIG. 3 is a flowchart of a procedure for sharing a frequency spectrum between NR and 6G systems according to one embodiment of the present disclosure.

[0055] The NR base station (3-15) transmits Served Cell Information NR information including radio resource information that must be protected or that it uses to the 6G base station (3-10) (3-20). The Served Cell Information NR may include information on cells supported by the NR base station. In particular, for an NR frequency carrier that can share a frequency spectrum with the 6G base station, radio resource information that must be protected or that it uses may additionally be included in the frequency carrier. The Served Cell Information NR may include at least one of the following information.

[0056] - Basic information of the cell supported by the NR base station: PCI (Physical Cell Id), CGI (Cell Global Id), cell frequency information (e.g., ARFCN (absolute radio frequency channel number), frequency bandwidth), information on whether TDD (time division duplexing) / FDD (frequency division duplexing) is used (in case of TDD, TDD configuration information, i.e., NR slot format information for Uplink-Downlink symbols), etc. may be included.

[0057] - Synchronization information of a cell supported by an NR base station (cell time / frequency synchronization): valid SFN (system frame number) information, SFN timing information (offset, absolute time indicating the start of SFN 0), basic information of a radio frame (length, etc.) and timing information (timing synchronization, absolute time indicating the start of radio frame 0) may be included as the synchronization information.

[0058] - SS (synchronization signal) / PBCH (physical broadcast channel) block information of a cell supported by an NR base station: Radio resource information on which the SS / PBCH is transmitted, for example, the number of SS / PBCH blocks in a half frame and applied SCS (subcarrier spacing) information, SSB-MTC (minimum timing configuration) setting information (i.e., timing occasion location information on which the terminal can measure SSB), etc.

[0059] - A list of NR radio resources (frequency-time domain) information to be protected or used by NR base stations: One element of the list has one resource type information. The resource type is a type of signal / channel that uses the radio resource indicated by the element. For example, the signal / channel may be a synchronization signal block (SSB), a demodulation reference signal (DMRS), a channel state information-reference signal (CSI-RS), a physical downlink control channel (PDCCH), a physical downlink shared channel (PDSCH), etc. Each element in the list may indicate frequency information to be protected, i.e., Physical Resource Block (PRB) information, and Resource Element (RE) information (in bitmap format) to be protected for each PRB. The PRB information may have a periodic pattern. As the frequency information, a frequency band range (Hz) may be used instead of a PRB unit. Each element in the above list may include time position information of the PRB to be protected in the Frame (e.g., indicated by index information of a slot or subframe) and period information of the PRB to be protected (e.g., indicated in units of slots or subframes). As the time information, an absolute time (ms) may be used instead of the slot or subframe unit. Each element in the above list may include SCS (subcarrier spacing) information applied to the radio resource indicated by the element. In NR, various SCSs can be applied depending on the supported frequency band.The above SCS information is required to derive the length of slots and symbols, and can be used for scheduling while maintaining orthogonality with NR signals in a frequency shared by a 6G base station with an NR base station.

[0060] The NR base station and the 6G base station can exchange information about the types of traffic (voice, text, streaming data, delay-sensitive data, control information, etc.) that they need to transmit and receive on the shared frequency, the amount of traffic, and the priority of the traffic. The exchanged information can be used to determine how the base stations allocate and use the shared frequency radio resources. For example, the 6G base station can receive, from the NR base station, information about traffic to be transmitted and received with a terminal through radio resources used for frequency spectrum sharing with the NR base station, and allocate radio resources based on the information about the received traffic and the information about the traffic that the 6G base station will transmit and receive with the terminal. As another example, the 6G base station can transmit, to the NR base station, information about the traffic that the 6G base station will transmit and receive with a terminal, and the NR base station can allocate radio resources based on the information about the received traffic and the information about the traffic that the NR base station will transmit and receive with the terminal, and transmit the result back to the 6G base station. The allocation of frequency resources may be determined through consultation between the two base stations based on the above information, or may be determined by a predetermined network scheduler linked to the two base stations.

[0061] The 6G base station can transmit the Served Cell Information NR information provided by the NR base station or predetermined information processed based on the information to the idle mode or inactive mode terminal through system information (3-25). The processed predetermined information may include, for example, information indicating any one of a field corresponding to the Served Cell Information NR information received by the 6G base station, a container including the Served Cell Information NR information received by the 6G base station, or a list of radio resource information to be protected or used by the NR base station included in the Served Cell Information NR information received by the 6G base station. However, the processed predetermined information is not limited to the examples described above, and may also include information on frequency radio resources allocated based on information exchanged between the NR base station and the 6G base station, and information related to radio resources to be protected or used by the NR base station may be transmitted to the terminal in various types.

[0062] This can be used to exclude the terminal from performing 6G operations (e.g., communication operations with a 6G base station) using the radio resources indicated by the information. Thereafter, the terminal (3-05) switched to the connected mode can report its capability information to the 6G base station (3-30). The capability information can include an indicator indicating that the terminal can support MRSS. The 6G base station can transmit to the terminal Served Cell Information NR information provided by the NR or predetermined information processed based on the information using a predetermined RRC message (e.g., an RRC reconfiguration message) (3-35). The terminal can receive scheduling information from the 6G base station (3-40). The terminal can configure a packet to be transmitted to the 6G base station based on the radio resource information used by the NR and the scheduling information, and check the radio resource to transmit the packet (3-45). For example, the terminal may exclude radio resources used by NR from the radio resources scheduled to the terminal, and transmit rate-matched data to the 6G base station according to the available radio resources.

[0063] FIG. 4 is a diagram illustrating how NR and 6G systems share a frequency spectrum according to one embodiment of the present disclosure.

[0064] In the drawing below, information on wireless resources to be protected or used by the NR base station may refer to information on wireless resources among the wireless resources used or allocated to be used by the NR base station, the use of which must be restricted or need to be restricted by the 6G base station, and may refer to information transmitted from the NR base station to the 6G base station.

[0065] A 6G base station can transmit to a terminal information on radio resources that need to be protected or that it uses, received from an NR base station. At this time, the 6G base station can transmit the information to the terminal as is or in a predetermined RRC signaling format. In the present embodiment, a method is proposed in which a 6G base station, considering the radio resources that need to be protected or that it uses, informs the terminal of radio resources that can be used in NR or radio resources that can be used in an NR 6G system, based on TDM (time division multiplexing) or scheduling.

[0066] FIG. 4 (a) is a diagram illustrating a method for a 6G base station to indicate to a terminal information on radio resources that should be protected or that it uses, based on TDM. According to FIG. 4 (a), in an NR frequency carrier shared with 6G, radio resources (4-05) that can be used in NR or radio resources (4-10) that can be used in an NR 6G system are indicated based on TDM. That is, radio resources used in NR and radio resources used in 6G are temporally separated. The above information can be provided for each configured 6G serving cell. In the above method, the 6G base station can provide at least one of the following information to the terminal.

[0067] - Center frequency information and bandwidth information of the NR frequency carrier shared with 6G: The center frequency may be indicated by ARFCN. The frequency bandwidth may be indicated in units of RB (resource blocks) applied in 6G. Since multiple NR frequency carriers may correspond to one 6G carrier, the information may also be provided in multiple pieces so as to indicate the multiple carriers.

[0068] - Pattern information of a symbol, slot, subframe, or radio frame that can be occupied and used by an NR or 6G system. The pattern information includes offset information and pattern period information that can identify the start time. Alternatively, a bitmap-type indication method can be utilized. For example, the position of a symbol that can be occupied by a 6G system in a slot that has radio resources that can be occupied and used by a 6G system can be indicated using a bitmap. Since there are a total of 14 symbols in one slot in NR, a bitmap with 14 bits can be defined. The unit length, start time, and period of the symbol, slot, subframe, or radio frame mentioned above can be derived based on the SFN applied in 6G.

[0069] FIG. 4 (b) is a diagram for explaining a method for a 6G base station to indicate to a terminal information on radio resources that must be protected or that it uses, based on scheduling. According to FIG. 4 (b), in an NR frequency carrier shared with 6G, radio resources (4-15) that can be used in NR, or radio resources (4-20) that can be used in an NR 6G system, are indicated based on scheduling. That is, radio resources used in NR and radio resources used in 6G may overlap in time. However, although the radio resources used in the two systems overlap in time, they must not overlap in frequency. Information on radio resources that can be used by 6G based on scheduling is composed of information based on the TDM basis described above, and may include information on radio resources that cannot be used due to certain NR signaling (e.g., NR SSB, DMRS, etc.) in a symbol, slot, subframe, or radio frame section that can be used by 6G. The information may be provided for each configured 6G serving cell. In the above method, the 6G base station can provide at least one of the following information to the terminal.

[0070] - Information proposed in the above TDM-based instruction method

[0071] - SSB (4-30) configuration information applied in NR. That is, carrier frequency information on which SSB is transmitted (e.g., ARFCN-ValueNR), subcarrier spacing information applied to SSB, SSB-MTC configuration information (i.e., timing occasion location information when the terminal can measure SSB).

[0072] - DMRS (4-25) configuration information applied in NR. DMRS frequency domain location information (type 1 or type 2 indication), DMRS time domain location information (type A or type B indication), number of DMRS symbols (1 or 2 symbols indication), whether additional DMRS is set in case of type B, and subcarrier spacing information applied to DMRS.

[0073] The above information may be indicated based on the SFN-based reference timing applied in 6G, and may also be indicated based on the reference timing applied in NR, depending on certain conditions or settings. The above-mentioned TDM-based and scheduling-based radio resource indication methods may be used together by the base station.

[0074] Indicating SSB or DMRS-related configuration information applied in the NR requires many fields and a large amount of information. However, MRSS implementations do not require as much detailed information as the SSB or DMRS-related configuration information. That is, only enough information is needed for a 6G terminal to recognize that it cannot use the corresponding radio resource in communication with a 6G base station due to NR signaling. Therefore, the present disclosure proposes a novel method for indicating radio resources that cannot be used by NR. For example, a 6G base station may provide the terminal with one or more frequency-time domain information related to the radio resources in the form of a list. The information may be provided for each 6G serving cell configured for the terminal. The frequency-time domain indicated in the information refers to the location of the radio resource allocated to NR. The frequency information in the frequency-time domain may be indicated in units of RBs applied in 6G, and the time information in the frequency-time domain may be indicated in units of symbol, slot, subframe, or radio frame applied in 6G. The above-described frequency-time domain may be periodic or aperiodic, and if periodic, offset and period information corresponding to the domain are provided to the terminal together. In addition, subcarrier spacing information applied to each frequency-time domain and information on the type of NR signaling or channel transmitted in the domain (e.g., types of reference signals such as SSB and DMRS, types of NR channels such as PDCCH and PDSCH, etc.) may also be provided to the terminal.

[0075] FIG. 5 is a flowchart illustrating terminal operation when NR and 6G systems share a frequency spectrum according to an embodiment of the present disclosure.

[0076] In step 5-05, the terminal reports its capability information to the 6G base station. The capability information includes an indicator indicating that the terminal supports MRSS.

[0077] In steps 5-10, the terminal receives configuration information required for MRSS from the 6G base station. The configuration information includes information indicating radio resources allocated to the NR base station on the NR frequency carrier or usable by the 6G base station.

[0078] In steps 5-15, the terminal transmits a rate-matched packet to the 6G base station, considering only the radio resources that the 6G can actually use, from the radio resources scheduled for the terminal.

[0079] FIG. 6 is a flowchart of a 6G base station operation when NR and a 6G system share a frequency spectrum according to an embodiment of the present disclosure.

[0080] In step 6-05, the 6G base station receives from the NR base station information about the cell being used by the NR base station and information about the radio resources occupied and used on each frequency carrier. Some of the frequency carriers may be used for MRSS purposes, and information indicating this may be transmitted to the 6G base station.

[0081] In steps 6-10, the 6G base station receives capability information from the terminal. This capability information includes an indicator indicating that the terminal supports MRSS. Based on this capability information, the 6G base station determines to provide service to the terminal using an NR frequency carrier capable of MRSS.

[0082] In steps 6-15, the 6G base station sets the NR frequency carrier for the terminal. At this time, the radio resource information received from the NR base station is converted into a predetermined information format and then transmitted to the terminal.

[0083] FIG. 7 is a diagram illustrating a case where a 6G system according to one embodiment of the present disclosure shares an LTE or NR frequency spectrum.

[0084] As mentioned above, the next-generation mobile communication system 6G is expected to provide 6G data services to users by sharing some frequency bands used in existing mobile communication systems, such as NR and LTE, with 7125 ~ 24250 MHz, referred to as FR3, as an alternative to addressing the insufficient radio resources. At this time, the existing LTE frequency carrier (7-05) and NR frequency carrier (7-10) can be shared with 6G, and 6G services can be enabled on the corresponding 6G frequency carriers (7-15, 7-20). The 6G frequency carriers shared with the frequencies of the above heterogeneous systems can be used to provide 6G services standalone, or can be configured in the form of CA (Carrier Aggregation) or DC (Dual Connectivity) with another 6G-dedicated frequency carrier (7-25) to provide 6G services. For example, as illustrated in FIG. 7, an LTE frequency carrier (7-05) can be shared and used with a 6G carrier (7-15), and an NR frequency carrier (7-10) can be shared and used with a 6G carrier (7-20). The 6G carriers (7-15, 7-20) shared with the LTE frequency carrier and the NR frequency carrier can be used as a PCell or an SCell in a CA scenario. In the CA scenario, the 6G carriers (7-15, 7-20) shared with the LTE frequency carrier and the NR frequency carrier can be aggregated and used with a predetermined 6G frequency carrier (7-25).

[0085] In LTE, cell-specific reference signals (CRSs) and in NR, reference signals (RSs), such as SSBs, are periodically transmitted by occupying certain radio resources. These RS signals are essential because they are primarily used for downlink synchronization or channel condition measurement. In MRSS, multiple systems share a single frequency carrier, necessitating efficient use of radio resources. This disclosure proposes a method for utilizing the RSs of heterogeneous systems for specific 6G operations (downlink synchronization, channel measurement, etc.) in a shared frequency spectrum.

[0086] The physical layer of the 6G system is expected to inherit the OFDM(A)-based framework of the NR system. Therefore, if RSs from other systems are available in the 6G system, the 6G base station can save radio resources required for 6G RS transmission in the shared frequency spectrum by not transmitting 6G-specific RSs or transmitting them at a longer period than the existing RS transmission period. The saved radio resources can be utilized to transmit user data, which can contribute to improving the throughput of 6G services and can also save power consumed by the 6G base station when transmitting its own RS.

[0087] FIG. 8 is a diagram illustrating the proportion of wireless resources occupied by NR reference signals according to one embodiment of the present disclosure.

[0088] The NR reference signal, SSB, is broadcast at a predetermined cycle determined by the system settings (SCS, number of SSBs in a half frame, etc.). If 4 SSBs are configured in a half frame (8-05) at a 15 kHz SCS, two SSB blocks (8-15, 8-25) are located in the first two subframes, respectively. The ratio of radio resources occupied by the two SSB blocks in one subframe (8-10) exceeds approximately 45%. This means that the radio resources available for transmitting user data are reduced. If another RS, DMRS (8-20), is also considered, the throughput performance is further reduced. If the radio resources are shared with 6G and 6G RSs are also transmitted, the throughput performance will deteriorate further. On the other hand, if NR RSs transmitted in the radio resources are utilized instead of transmitting 6G RSs for 6G operation, some of the throughput performance degradation can be suppressed.

[0089] FIG. 9 is a diagram illustrating a co-located 6G-NR or co-located 6G-LTE scenario according to one embodiment of the present disclosure.

[0090] For 6G terminals to utilize NR RS in a shared frequency spectrum, the 6G base station and NR base station must be co-located. Otherwise, NR RS cannot represent the channel changes experienced by 6G signals in the corresponding frequency spectrum. Therefore, this disclosure proposes a method for utilizing RS of heterogeneous systems during a given 6G operation in a co-located 6G-NR or co-located 6G-LTE scenario.

[0091] FIG. 9 (a) is a diagram illustrating a co-located 6G-NR scenario (9-05). In the shared NR frequency spectrum (9-20), either a 6G PCell or a 6G SCell can be configured. If a 6G PCell is configured in a 6G dedicated frequency (9-10) and a 6G SCell (9-15) is configured in the shared frequency spectrum, the 6G base station can provide predetermined configuration information required to utilize SSB, which is an NR RS, in the 6G SCell through the 6G PCell. In the present disclosure, the 6G SCell and the NR cell (PCell or SCell) configured in the shared frequency spectrum have downlink timing synchronization. That is, the boundaries of (sub)frames or slots are synchronized. When the downlink synchronization is synchronized and the applied SCS is the same, the terminal can orthogonally decode the 6G signal and the NR signal received at the same time. Accordingly, the terminal can obtain the downlink synchronization of the 6G SCell through the NR SS / PBCH and MIB (master information block) received in the shared frequency spectrum. The terminal can recognize the (sub)frame / slot boundary through the NR SSB, and can derive the 6 MSB (most significant bit) value of the SFN using the 4 LSB (least significant bit) of the SFN in the PBCH transport block and the systemFrameNumber field value stored in the MIB. The terminal can derive the SFN applied to the 6G SCell based on the derived NR SFN.

[0092] FIG. 9 (b) is a diagram illustrating a co-located 6G-LTE scenario (9-25). In the shared LTE frequency spectrum (9-40), either a 6G PCell or a 6G SCell can be configured. If a 6G PCell is configured in a 6G dedicated frequency (9-30) and a 6G SCell (9-35) is configured in the shared frequency spectrum, the 6G base station can provide predetermined configuration information necessary for utilizing CRS, which is an LTE RS, in the 6G SCell through the 6G PCell. In the present disclosure, the 6G SCell and the LTE cell (PCell or SCell) configured in the shared frequency spectrum have matching downlink synchronization. That is, the boundaries of frames or slots are aligned. When the downlink synchronization is matching and the applied SCS is the same, the terminal can orthogonally decode the 6G signal and the LTE signal received at the same time. Accordingly, the terminal can obtain the downlink synchronization of the 6G SCell through the LTE SS (Synchronization Signal), PBCH, and MIB received in the shared frequency spectrum. The terminal can recognize the (sub)frame boundary through the LTE SS, and can derive the 8 MSB value of the LTE SFN by implicitly using the 2 LSB of the LTE SFN and the systemFrameNumber field value stored in the MIB during the PBCH decoding process. The terminal can derive the SFN applied to the 6G SCell based on the derived LTE SFN.

[0093] The 6G PCell can also be configured in the NR or LTE frequency spectrum. Since the 6G PCell must be able to independently service terminals without the assistance of other serving cells, it must broadcast 6G RSs and essential system information in the shared frequency spectrum. Consequently, the utilization of RSs from heterogeneous systems may be reduced. However, utilizing RSs from heterogeneous systems in the shared frequency spectrum for the 6G PCell can further improve performance, such as by enabling more accurate channel condition identification.

[0094] FIG. 10 is a flowchart of a procedure for using an NR reference signal for 6G operation in a co-located 6G-NR or co-located 6G-LTE scenario according to one embodiment of the present disclosure.

[0095] The 6G NB (10-15) and gNB (or eNB, 10-30) are co-located (10-10). That is, the antennas of both base stations are installed in the same location. The 6G NB can support CA or DC scenarios, and can be configured with one PCell (10-20) and one or more SCells (10-25).

[0096] The gNB (or eNB) may provide its serving cell information (e.g., Served Cell Information NR information described in FIGS. 3 and 4 or Served Cell Information EUTRA information including at least one of the information included in the Served Cell Information NR information) to the 6G NB (10-35). The information may be retransmitted to the gNB periodically or when a specific event occurs (e.g., when all or a predetermined part of the serving cell information is updated). Information that may be included in the serving cell information is described above in FIG. 3.

[0097] A 6G terminal (10-05) can report its capability information to the 6G NB (10-40). The capability information may include an indicator indicating that the terminal can support its own MRSS, and an indicator indicating that it can receive a predetermined reference signal (e.g., SSB in NR, CRS in LTE) transmitted from a heterogeneous system (e.g., NR or LTE) and utilize it for 6G operation.

[0098] The 6G NB may transmit to the terminal a predetermined message (e.g., an RRC message) containing predetermined configuration information reflecting the information received from the gNB (10-45). The predetermined configuration information refers to CA or DC-related configuration information, MRSS-related configuration information (all or part of the information disclosed in FIG. 4), and configuration information related to using an NR reference signal. The terminal that has received the configuration information applies the CA or DC configuration information to additionally consider the configured SCell. For each configured SCell, MRSS-related configuration information and configuration information related to using an NR reference signal may be provided.

[0099] The above terminal can receive SSB and MIB transmitted from the gNB recognized according to the above setting information (10-50).

[0100] The terminal can synchronize downlink using the SSB (and MIB) received from the gNB. For example, the terminal can identify the (sub)frame / slot boundary through the received NR SSB. In addition, the NR SFN can be derived using the systemFrameNumber field value stored in the PBCH transport block and MIB (10-55). Based on the NR SFN, the terminal can derive the SFN applied to the 6G SCell using predetermined configuration information. The configuration information is the difference value between the NR SFN value and the SFN value applied to the 6G SCell. The difference value can be indicated in absolute time or in units of predetermined (sub)frame, slot, or symbol. For example, if the current NR SFN value is 3 and the predetermined difference value is 2 through the received NR SSB and MIB, the current 6G SFN value becomes 5. The SFN value applied to the above 6G SCell may be the same as the SFN value of the 6G PCell, in which case there is no need to separately derive the SFN value applied to the 6G SCell as described above. The 6G base station may also provide the terminal with the configuration information of the NR SSB or LTE CRS by including it in the measObject, which is cell measurement information.

[0101] The above terminal can perform random access to the 6G SCell to achieve uplink synchronization (10-60).

[0102] The terminal may transmit a Measurement Report message including the results measured via NR SSB to a 6G base station according to a predetermined setting. The terminal triggers the transmission of the message when a predetermined set event evaluated based on the measured results is satisfied. Since one 6G carrier may share a frequency spectrum with one or more NR carriers, all of the multiple NR SSBs transmitted from multiple NR cells may be considered in the measurement. The measurement values ​​of the multiple NR SSBs transmitted from multiple NR cells may be L3-filtered and used for a predetermined event-triggered measurement operation (10-65).

[0103] In another way, depending on the base station settings, the measurement value of the SSB of a predetermined NR cell among multiple NR cells or a predetermined NR cell set by the base station may be L3-filtered and used for a predetermined event-triggered measurement operation. Generally, the measurement event of intra-RAT is classified as Event A type (e.g., Event A1, Event A2, ...), and the measurement event of other system (inter-RAT) is classified as Event B (e.g., Event B1, B2). Even though it is a measurement result of the SSB of NR, which is another system, if the NR SSB is used for 6G operation, the measurement value of the NR SSB may be applied to the configured Event A as well. To this end, the 6G base station may use a predetermined indicator to set whether to apply the measurement value of the NR SSB to the Event A set for the terminal. In another way, a new Event B having the condition of Event A may be defined. For example, the following new Event B may be defined. The measurement values ​​of the serving cell or neighbor cell below are derived based on NR SSB or LTE CRS, and the measurement values ​​of NR SSB or LTE CRS broadcast from multiple cells can be applied.

[0104] - Event B3: Serving becomes worse than absolute threshold

[0105] - Event B4: Neighbor becomes amount of offset better than PCell / PSCell

[0106] - Event B5: Neighbor becomes better than absolute threshold

[0107] - Event B6: Neighbor becomes amount of offset better than SCell

[0108] Measuring only NR SSB in a shared spectrum to perform certain 6G operations may be insufficient for data transmission and reception and channel state assessment, such as demodulation and channel state information (CSI). For 6G data transmission and reception, a specific UE-specific reference signal specific to 6G signals may be required. Accordingly, the 6G NB may configure a UE-specific 6G reference signal for the UE (10-75). The UE configured with the UE-specific 6G reference signal can receive both NR SSB and the UE-specific 6G reference signal and perform certain 6G operations.

[0109] The above gNB can provide its serving cell information including updated information (10-80).

[0110] The 6G NB that has received the above information can transmit CA or DC related configuration information reflecting the above information, MRSS related configuration information, or configuration information related to using the NR reference signal to the terminal (10-85).

[0111] The above terminal can request a (common) 6G reference signal using the UEAssistanceInformation message, or request the 6G NB to update the previously applied NR SSB if it changes (10-95).

[0112] If the 6G NB determines that the requested 6G reference signal is necessary, it broadcasts it. In addition, the 6G NB can configure the terminal using a predetermined RRC message whether to use only the 6G reference signal or to use both the 6G reference signal and NR SSB. If both are configured to be used, the terminal can use the measurement values ​​of the 6G reference signal and SSB for a predetermined event-triggered measurement operation by L3-filtering them (10-100).

[0113] If a predetermined event condition is satisfied based on the above measurement value, the terminal transmits a measurement report to the 6G NB (10-105).

[0114] In another embodiment, NR SSB or LTE CRS can also be utilized for the following 6G operations.

[0115] - Idle mode measurement

[0116] The above Idle mode measurement (or Early measurement) is a technology in which the base station reports the most recent cell measurement results collected before the terminal switches to connected mode to the base station after switching to connected mode for the purpose of quickly setting up SCells for the terminal that has switched to connected mode. Existing idle mode measurement can also measure and report inter-RAT frequencies. In the present disclosure, for more precise measurement, it is proposed that the 6G base station provide the terminal with information on the inter-RAT frequency and cell SSB configuration to be measured in idle mode measurement through a 6G RRC release message or system information. In addition, since a single 6G carrier may share the frequency spectrum of one or more NR carriers, the terminal can report measurement values ​​that take into account all of the NR SSBs transmitted from multiple NR cells, depending on the configuration of the base station.

[0117] - Cell measurement in standby or inactive mode

[0118] A 6G terminal in standby or inactive mode can camp on the shared frequency spectrum, and at this time, trigger cell reselection operation based on the results of measuring NR SSB or LTE CRS. To this end, the 6G base station can provide the terminal with configuration information for the NR SSB or LTE CRS through predetermined system information broadcast on the shared frequency spectrum.

[0119] FIG. 11 is a flowchart of a terminal operation using an NR reference signal for 6G operation in a co-located 6G-NR or co-located 6G-LTE scenario according to an embodiment of the present disclosure.

[0120] In step 11-05, the terminal reports its capability information to the 6G NB. The capability information includes an indicator indicating that the terminal can support its own MRSS, as well as an indicator indicating that it can receive a specific reference signal transmitted from a heterogeneous system and utilize it for 6G operation.

[0121] In step 11-10, the terminal receives a predetermined RRC message including predetermined CA or DC related configuration information, MRSS related configuration information, and configuration information related to using an NR reference signal from the 6G NB.

[0122] In steps 11-15, the terminal receives SSB from the NR base station (gNB) according to the above settings.

[0123] In steps 11-20, the terminal synchronizes the downlink using the SSB (and MIB) received from the NR base station.

[0124] In steps 11-25, the terminal performs random access to the 6G NB to synchronize uplink.

[0125] In steps 11-30, the terminal transmits to the 6G NB a predetermined RRC message including the measurement result of the SSB received from the NR base station.

[0126] In steps 11-35, when the terminal determines that transmission of a 6G RS (reference signal) is necessary, the terminal may request (on-demand) transmission of the 6G RS or request update of NR SSB to the 6G NB using a predetermined RRC message (e.g., UE assistance information).

[0127] In steps 11-40, the terminal receives a 6G reference signal broadcasted from the 6G NB based on the request.

[0128] FIG. 12 is a flowchart of base station operations using NR reference signals for 6G operations in a co-located 6G-NR or co-located 6G-LTE scenario according to one embodiment of the present disclosure.

[0129] In step 12-05, the 6G base station receives NR serving cell information from an adjacent NR base station.

[0130] In step 12-10, the 6G base station receives terminal capability information from the terminal.

[0131] In steps 12-15, the 6G base station transmits to the terminal a predetermined RRC message (e.g., RRC reconfiguration) including CA or DC related configuration information, MRSS related configuration information, and configuration information related to using an NR reference signal, based on NR serving cell information provided from the adjacent NR base station.

[0132] In steps 12-20, the 6G base station supports a random access process for the terminal.

[0133] In steps 12-25, the 6G base station receives a predetermined RRC message including the measurement result of SSB received from the NR base station from the terminal.

[0134] In steps 12-30, the 6G base station receives an RRC message (e.g., UE assistance information) requesting transmission of a 6G reference signal or requesting update of NR SSB from the terminal.

[0135] In steps 12-35, the 6G base station broadcasts a 6G reference signal at the request of the base station.

[0136] FIG. 13 is a block diagram illustrating the internal structure of a terminal according to an embodiment of the present disclosure.

[0137] Referring to the above drawing, the terminal includes an RF (Radio Frequency) processing unit (13-10), a baseband processing unit (13-20), a storage unit (13-30), and a control unit (13-40).

[0138] The RF processing unit (13-10) performs functions for transmitting and receiving signals through a wireless channel, such as signal band conversion and amplification. That is, the RF processing unit (13-10) up-converts the baseband signal provided from the baseband processing unit (13-20) into an RF band signal and transmits it through an antenna, and down-converts the RF band signal received through the antenna into a baseband signal. For example, the RF processing unit (13-10) may include a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a digital to analog convertor (DAC), an analog to digital convertor (ADC), etc. In the drawing, only one antenna is shown, but the terminal may be equipped with multiple antennas. In addition, the RF processing unit (13-10) may include multiple RF chains. Furthermore, the RF processing unit (13-10) may perform beamforming. For the above beamforming, the RF processing unit (13-10) can adjust the phase and size of each signal transmitted and received through multiple antennas or antenna elements. In addition, the RF processing unit can perform MIMO and receive multiple layers when performing the MIMO operation.

[0139] The baseband processing unit (13-20) performs a conversion function between a baseband signal and a bit stream according to the physical layer specifications of the system. For example, when transmitting data, the baseband processing unit (13-20) generates complex symbols by encoding and modulating a transmission bit stream. In addition, when receiving data, the baseband processing unit (13-20) restores the reception bit stream by demodulating and decoding the baseband signal provided from the RF processing unit (13-10). For example, in the case of following the OFDM (orthogonal frequency division multiplexing) method, when transmitting data, the baseband processing unit (13-20) generates complex symbols by encoding and modulating a transmission bit stream, maps the complex symbols to subcarriers, and then configures OFDM symbols through an inverse fast Fourier transform (IFFT) operation and a cyclic prefix (CP) insertion. In addition, when receiving data, the baseband processing unit (13-20) divides the baseband signal provided from the RF processing unit (13-10) into OFDM symbol units, restores signals mapped to subcarriers through FFT (fast Fourier transform) operation, and then restores the received bit string through demodulation and decoding.

[0140] The baseband processing unit (13-20) and the RF processing unit (13-10) transmit and receive signals as described above. Accordingly, the baseband processing unit (13-20) and the RF processing unit (13-10) may be referred to as a transmitter, a receiver, a transceiver, or a communication unit. Furthermore, at least one of the baseband processing unit (13-20) and the RF processing unit (13-10) may include a plurality of communication modules to support a plurality of different wireless access technologies. In addition, at least one of the baseband processing unit (13-20) and the RF processing unit (13-10) may include different communication modules to process signals of different frequency bands. For example, the different wireless access technologies may include a wireless LAN (e.g., IEEE 802.11), a cellular network (e.g., LTE), etc. Additionally, the different frequency bands may include a super high frequency (SHF) (e.g., 2.NRHz, NRhz) band and a millimeter wave (mm wave) (e.g., 60GHz) band.

[0141] The storage unit (13-30) stores data such as basic programs, application programs, and setting information for the operation of the terminal. In particular, the storage unit (13-30) can store information related to a second access node that performs wireless communication using a second wireless access technology. In addition, the storage unit (13-30) provides the stored data at the request of the control unit (13-40).

[0142] The control unit (13-40) controls the overall operations of the terminal. For example, the control unit (13-40) transmits and receives signals through the baseband processing unit (13-20) and the RF processing unit (13-10). In addition, the control unit (13-40) records and reads data in the storage unit (13-40). For this purpose, the control unit (13-40) may include at least one processor. For example, the control unit (13-40) may include a communication processor (CP) that performs control for communication and an application processor (AP) that controls upper layers such as application programs.

[0143] FIG. 14 is a block diagram illustrating the structure of a base station according to one embodiment of the present disclosure.

[0144] As shown in the above drawing, the base station is configured to include an RF processing unit (14-10), a baseband processing unit (14-20), a backhaul communication unit (14-30), a storage unit (14-40), and a control unit (14-50).

[0145] The RF processing unit (14-10) performs functions for transmitting and receiving signals through a wireless channel, such as signal band conversion and amplification. That is, the RF processing unit (14-10) up-converts the baseband signal provided from the baseband processing unit (14-20) into an RF band signal and transmits it through an antenna, and down-converts the RF band signal received through the antenna into a baseband signal. For example, the RF processing unit (14-10) may include a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a DAC, an ADC, etc. In the drawing, only one antenna is shown, but the first access node may have multiple antennas. In addition, the RF processing unit (14-10) may include multiple RF chains. Furthermore, the RF processing unit (14-10) may perform beamforming. For the above beamforming, the RF processing unit (14-10) can adjust the phase and size of each signal transmitted and received through multiple antennas or antenna elements. The RF processing unit can perform a downlink MIMO operation by transmitting one or more layers.

[0146] The baseband processing unit (14-20) above performs a conversion function between a baseband signal and a bit stream according to the physical layer specifications of the first wireless access technology. For example, when transmitting data, the baseband processing unit (14-20) generates complex symbols by encoding and modulating a transmission bit stream. In addition, when receiving data, the baseband processing unit (14-20) restores the reception bit stream by demodulating and decoding the baseband signal provided from the RF processing unit (14-10). For example, in the case of OFDM, when transmitting data, the baseband processing unit (14-20) generates complex symbols by encoding and modulating a transmission bit stream, maps the complex symbols to subcarriers, and then configures OFDM symbols through IFFT operation and CP insertion. In addition, when receiving data, the baseband processing unit (14-20) divides the baseband signal provided from the RF processing unit (14-10) into OFDM symbol units, restores the signals mapped to subcarriers through FFT operation, and then restores the received bit string through demodulation and decoding. The baseband processing unit (14-20) and the RF processing unit (14-10) transmit and receive signals as described above. Accordingly, the baseband processing unit (14-20) and the RF processing unit (14-10) may be referred to as a transmitter, a receiver, a transceiver, a communication unit, or a wireless communication unit.

[0147] The above backhaul communication unit (14-30) provides an interface for performing communication with other nodes within the network. That is, the backhaul communication unit (14-30) converts a bit string transmitted from the main base station to other nodes, such as auxiliary base stations and core networks, into a physical signal, and converts a physical signal received from the other nodes into a bit string.

[0148] The storage unit (14-40) stores data such as basic programs, application programs, and setting information for the operation of the main base station. In particular, the storage unit (14-40) can store information on bearers assigned to connected terminals, measurement results reported from connected terminals, and the like. In addition, the storage unit (14-40) can store information that serves as a judgment criterion for whether to provide or terminate multiple connections to a terminal. In addition, the storage unit (14-40) provides the stored data at the request of the control unit (14-50).

[0149] The control unit (14-50) controls the overall operations of the base station. For example, the control unit (14-50) transmits and receives signals through the baseband processing unit (14-20) and the RF processing unit (14-10) or through the backhaul communication unit (14-30). In addition, the control unit (14-50) records and reads data in the storage unit (14-40). For this purpose, the control unit (14-50) may include at least one processor.

[0150] While the detailed description of this disclosure has described specific embodiments, it should be understood that various modifications are possible without departing from the scope of this disclosure. Therefore, the scope of this disclosure should not be limited to the described embodiments, but should be defined not only by the scope of the claims described below, but also by equivalents thereof.

Claims

1. A method performed by a first base station associated with a first RAT (radio access technology) in a wireless communication system, A step of receiving, from a second base station associated with a second RAT, information about a first wireless resource used for frequency spectrum sharing with the first RAT and the second RAT, wherein the information about the first wireless resource includes information about a second wireless resource to be used by the second base station among the first wireless resources and information about a subcarrier spacing (SCS) applied to the second wireless resource; A step of transmitting configuration information including the information about the first wireless resource to the terminal; and A method of a first base station, comprising: receiving data from the terminal based on valid radio resources, from which the second radio resource is excluded, among the radio resources scheduled based on the SCS.

2. In paragraph 1, The information about the first wireless resource further includes resource type information indicating the type of signal for which the first wireless resource is used, The above resource type information includes at least one of a demodulation reference signal (DMRS) or a synchronization signal block (SSB), The information about the second wireless resource indicates the location of the second wireless resource within the first wireless resource, The above first RAT is 6G (6 th generation) and the second RAT is NR (new radio), and A method of a first base station, characterized in that the data is transmitted based on rate-matching for the valid wireless resources.

3. In paragraph 1, The first base station and the second base station are co-located, The above configuration information further includes an indicator indicating downlink synchronization based on a reference signal of the second RAT, Based on the reference signal of the second RAT, downlink synchronization of the serving cell of the first base station and the serving cell of the second base station set in the first wireless resource is performed, and A method of a first base station, characterized in that a measurement result based on the reference signal of the second RAT is received from the terminal.

4. In paragraph 1, Further comprising a step of receiving capability information including an indicator indicating that the terminal supports MRSS (multi RAT spectrum sharing) from the terminal; A method of a first base station, characterized in that the above setting information is transmitted based on the above capability information.

5. In paragraph 1, A step of receiving second traffic information about traffic to be transmitted to or received from the terminal by the second base station through the first wireless resource from the second base station; and Further comprising a step of allocating wireless resources based on first traffic information and second traffic information for traffic to be transmitted to or received from the terminal by the first base station through the first wireless resource; A method of a first base station, characterized in that the above setting information further includes information about the allocated wireless resources.

6. In a method performed by a terminal in a wireless communication system, A step of receiving configuration information including information about a first wireless resource used for frequency spectrum sharing with the first RAT and a second RAT from a first base station associated with a first RAT, wherein the information about the first wireless resource includes information about a second wireless resource to be used by a second base station associated with the second RAT among the first wireless resources and information about a subcarrier spacing (SCS) applied to the second wireless resource; and A step of transmitting data based on valid radio resources, excluding the second radio resource among the radio resources scheduled based on the SCS, to the first base station; A method of a terminal, characterized in that the information about the first wireless resource is transmitted from the second base station to the first base station.

7. In paragraph 6, The information about the first wireless resource further includes resource type information indicating the type of signal for which the first wireless resource is used, The above resource type information includes at least one of a demodulation reference signal (DMRS) or a synchronization signal block (SSB), The information about the second wireless resource indicates the location of the second wireless resource within the first wireless resource, The above first RAT is 6G (6 th generation) and the second RAT is NR (new radio), and A method of a terminal, characterized in that the above data is transmitted based on rate-matching for the valid wireless resources.

8. In paragraph 6, Further comprising a step of transmitting capability information including an indicator indicating that the terminal supports MRSS (multi RAT spectrum sharing) to the first base station; The above setting information is received based on the above capability information, The first base station and the second base station are co-located, The above configuration information further includes an indicator indicating downlink synchronization based on a reference signal of the second RAT, Based on the reference signal of the second RAT, downlink synchronization of the serving cell of the first base station and the serving cell of the second base station set in the first wireless resource is performed, and A method of a terminal, characterized in that the measurement result based on the reference signal of the second RAT is transmitted to the first base station.

9. In a first base station associated with a first RAT (radio access technology) in a wireless communication system, At least one transceiver; At least one processor connected to communicate with at least one transceiver; and Communicably connected to at least one processor and executable by the at least one processor, wherein the first base station, Receive information about a first wireless resource used for frequency spectrum sharing with the first RAT and the second RAT from a second base station associated with the second RAT, wherein the information about the first wireless resource includes information about a second wireless resource to be used by the second base station among the first wireless resources and information about a subcarrier spacing (SCS) applied to the second wireless resource. Transmits configuration information including the above information about the first wireless resource to the terminal, and A first base station, comprising: a memory storing a command that causes data to be received from the terminal based on valid radio resources, excluding the second radio resource from among the radio resources scheduled based on the SCS; 10. In paragraph 9, The information about the first wireless resource further includes resource type information indicating the type of signal for which the first wireless resource is used, The above resource type information includes at least one of a demodulation reference signal (DMRS) or a synchronization signal block (SSB), The information about the second wireless resource indicates the location of the second wireless resource within the first wireless resource, The above first RAT is 6G (6 th generation) and the second RAT is NR (new radio), and A first base station, characterized in that the data is transmitted based on rate-matching for the valid wireless resources.

11. In paragraph 10, The above command further causes the first base station to receive capability information from the terminal, including an indicator indicating that the terminal supports MRSS (multi RAT spectrum sharing), The above setting information is transmitted based on the above capability information, The first base station and the second base station are co-located, The above configuration information further includes an indicator indicating downlink synchronization based on a reference signal of the second RAT, Based on the reference signal of the second RAT, downlink synchronization of the serving cell of the first base station and the serving cell of the second base station set in the first wireless resource is performed, and A first base station, characterized in that a measurement result based on the reference signal of the second RAT is received from the terminal.

12. In paragraph 10, The above command causes the first base station to: Receive second traffic information about traffic to be transmitted to or received from the terminal by the second base station through the first wireless resource from the second base station, and Further causing the first base station to allocate radio resources based on first traffic information and second traffic information for traffic to be transmitted to or received from the terminal through the first radio resource, and A first base station, characterized in that the above setting information further includes information on the allocated wireless resources.

13. In a wireless communication system, at a terminal, At least one transceiver; At least one processor connected to communicate with at least one transceiver; and Communicably connected to at least one processor and executable by at least one processor, wherein the terminal, Receiving configuration information including information about a first wireless resource used for frequency spectrum sharing with the first RAT and the second RAT from a first base station associated with the first RAT, wherein the information about the first wireless resource includes information about a second wireless resource to be used by a second base station associated with the second RAT among the first wireless resources and information about a subcarrier spacing (SCS) applied to the second wireless resource, and A memory storing a command that causes the first base station to transmit data based on valid radio resources, excluding the second radio resource among the radio resources scheduled based on the SCS; A terminal, characterized in that the information about the first wireless resource is transmitted from the second base station to the first base station.

14. In paragraph 13, The information about the first wireless resource further includes resource type information indicating the type of signal for which the first wireless resource is used, The above resource type information includes at least one of a demodulation reference signal (DMRS) or a synchronization signal block (SSB), The information about the second wireless resource indicates the location of the second wireless resource within the first wireless resource, The above first RAT is 6G (6 th generation) and the second RAT is NR (new radio), and A terminal characterized in that the above data is transmitted based on rate-matching for the valid wireless resources.

15. In paragraph 13, The above command further causes the terminal to transmit capability information including an indicator indicating that the terminal supports MRSS (multi RAT spectrum sharing) to the first base station, The above setting information is received based on the above capability information, The first base station and the second base station are co-located, The above configuration information further includes an indicator indicating downlink synchronization based on a reference signal of the second RAT, Based on the reference signal of the second RAT, downlink synchronization of the serving cell of the first base station and the serving cell of the second base station set in the first wireless resource is performed, and A terminal characterized in that the measurement result based on the reference signal of the second RAT is transmitted to the first base station.

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