Method and apparatus for controlling interference in wireless communication system

Abstract

The present disclosure relates to a 5G or 6G communication system for supporting higher data transmission rates. In a wireless communication system, a fixed wireless access (FWA) apparatus comprises a transceiver and a controller coupled to the transceiver, and the controller may be configured to: receive, from a first base station, configuration information about interference management associated with a second base station; when reception of a physical downlink shared channel (PDSCH) from the first base station fails, identify, on the basis of the configuration information, whether the failure of the reception of the PDSCH is based on interference associated with the second base station; and transmit, to the first base station, uplink control information (UCI) including information indicating whether the failure of the reception of the PDSCH is based on the interference.

Description

Method and device for controlling interference in a wireless communication system

[0001] The present disclosure relates to a wireless communication system (or, mobile communication system). Specifically, the present disclosure relates to a method and apparatus for controlling interference in a wireless communication system.

[0002] Looking back at the evolution of wireless communication through successive generations, technologies have been developed primarily for human-oriented services, such as voice, multimedia, and data. Following the commercialization of 5G (5th Generation) communication systems, connected devices, which have been increasing explosively, are expected to be connected to communication networks. Examples of networked objects include vehicles, robots, drones, home appliances, displays, smart sensors installed in various infrastructures, construction machinery, and factory equipment. Mobile devices are expected to evolve into various form factors, such as augmented reality glasses, virtual reality headsets, and holographic devices. In the 6G (6th Generation) era, efforts are underway to develop improved 6G communication systems to connect hundreds of billions of devices and objects to provide diverse services. For this reason, 6G communication systems are being referred to as "beyond 5G" systems.

[0003] In the 6G communication system predicted to be realized around 2030, the maximum transmission speed is tera (i.e., 1,000 gigabit) bps (bit per second), and the wireless latency is 100 microseconds (μsec). In other words, compared to the 5G communication system, the transmission speed in the 6G communication system is 50 times faster, and the wireless latency is reduced to one-tenth.

[0004] To achieve such high data transmission speeds and ultra-low latency, 6G communication systems are being considered for implementation in the terahertz (THz) band (e.g., the 95 gigahertz (GHz) to 3 terahertz (3THz) band). Due to more severe path loss and atmospheric absorption phenomena compared to the millimeter wave (mmWave) band introduced in 5G, the importance of technologies capable of guaranteeing signal reach, or coverage, is expected to increase in the terahertz band. As key technologies to ensure coverage, new waveforms, beamforming, and multi-antenna transmission technologies such as massive Multiple-Input and Multiple-Output (MIMO), Full Dimensional MIMO (FD-MIMO), array antennas, and large-scale antennas, which are superior in terms of coverage compared to RF (Radio Frequency) devices, antennas, and OFDM (Orthogonal Frequency Division Multiplexing), must be developed. In addition, new technologies such as metamaterial-based lenses and antennas, high-dimensional spatial multiplexing technology using Orbital Angular Momentum (OAM), and Reconfigurable Intelligent Surface (RIS) are being discussed to improve the coverage of terahertz band signals.

[0005] In addition, to improve frequency efficiency and system network, development is underway in 6G communication systems for full duplex technology, in which uplink and downlink simultaneously utilize the same frequency resources at the same time; network technology that integrates satellites and HAPS (High-Altitude Platform Stations); network structure innovation technology that supports mobile base stations and enables network operation optimization and automation; dynamic spectrum sharing technology through collision avoidance based on spectrum usage prediction; AI-based communication technology that utilizes AI (Artificial Intelligence) from the design stage and internalizes end-to-end AI support functions to realize system optimization; and next-generation distributed computing technology that realizes services of complexity exceeding the limits of terminal computing capabilities by utilizing ultra-high performance communication and computing resources (Mobile Edge Computing (MEC), cloud, etc.). In addition, attempts are continuing to further strengthen connectivity between devices, further optimize networks, promote the softwareization of network entities, and increase the openness of wireless communication through the design of new protocols to be used in 6G communication systems, the implementation of hardware-based security environments, the development of mechanisms for the safe utilization of data, and the development of technologies regarding privacy maintenance methods.

[0006] Due to the research and development of such 6G communication systems, it is expected that a new dimension of hyper-connected experience will become possible through the hyper-connectivity of 6G communication systems, which encompasses not only connections between objects but also connections between people and objects. Specifically, it is projected that 6G communication systems will enable the provision of services such as truly immersive eXtended Reality (XR), high-fidelity mobile holograms, and digital replicas. Furthermore, services such as remote surgery, industrial automation, and emergency response, which are provided through 6G communication systems with enhanced security and reliability, will be applied in various fields including industry, healthcare, automotive, and home appliances.

[0007] When an FWA device communicates with a first base station, interference (e.g., instantaneous interference (IIF)) may occur due to the scheduling of an adjacent second base station. If no information exchange occurs between the first and second base stations, it may be difficult to prevent interference (e.g., IIF) associated with the second base station.

[0008] Furthermore, there may be a problem where data throughput is unnecessarily reduced when the MCS level is lowered due to interference associated with the second base station (e.g., IIF). For instance, if the actual SINR value of the first base station is lower than the expected SINR value, the MCS level may continuously decrease, leading to reduced data throughput. However, if the cause of the lowered actual SINR value is interference associated with the second base station (e.g., IIF), the interference may be temporary, and there may be no need to lower the MCS level at the expense of reducing data throughput. Nevertheless, since it is impossible to identify whether the reason for the lowered actual SINR value is due to interference associated with the second base station (e.g., IIF), there may be a problem where the MCS level and data throughput are unnecessarily reduced.

[0009] According to one embodiment, a fixed wireless access (FWA) device in a wireless communication system includes a transceiver and a controller coupled to the transceiver, and the controller may be configured to receive configuration information regarding interference management associated with a second base station from a first base station, and, if reception of a physical downlink shared channel (PDSCH) from the first base station fails, identify whether the failure of reception of the PDSCH is based on interference associated with the second base station based on the configuration information, and transmit uplink control information (UCI) to the first base station, the UCI including information indicating whether the failure of reception of the PDSCH is based on the interference.

[0010] According to one embodiment, a method performed by a fixed wireless access (FWA) device in a wireless communication system may include: receiving configuration information for interference management associated with a second base station from a first base station; identifying, based on the configuration information, whether the failure to receive a physical downlink shared channel (PDSCH) from the first base station is due to interference associated with the second base station when the reception of the PDSCH fails; and transmitting uplink control information (UCI) to the first base station, the UCI including information indicating whether the failure to receive the PDSCH is due to interference.

[0011] According to one embodiment, in a wireless communication system, a first base station includes a transceiver and a controller coupled to the transceiver, and the controller may be configured to transmit configuration information regarding interference management associated with a second base station to a fixed wireless access (FWA) device, and to receive uplink control information (UCI) from the FWA device, which includes information indicating whether the failure of the transmission of the physical downlink shared channel (PDSCH) to the FWA device is based on interference associated with the second base station, when the transmission of the physical downlink shared channel (PDSCH) to the FWA device fails.

[0012] According to one embodiment, a method performed by a first base station in a wireless communication system may include the steps of transmitting configuration information for interference management associated with a second base station to a fixed wireless access (FWA) device, and receiving uplink control information (UCI) from the FWA device, which includes information indicating whether the failure of the transmission of the physical downlink shared channel (PDSCH) to the FWA device is based on interference associated with the second base station, when the transmission of the physical downlink shared channel (PDSCH) to the FWA device fails.

[0013] According to one embodiment, the reduction in throughput between the FWA device and the first base station due to the IIF can be prevented.

[0014] According to one embodiment, by identifying an interference source (e.g., a transmission beam of a second base station) that causes IIF and replacing it with another transmission beam or changing the reception beam, future interference occurrences can be reduced or prevented.

[0015] In addition, various effects identified directly or indirectly through the present disclosure may be provided.

[0016] FIG. 1 illustrates a wireless communication system according to one embodiment.

[0017] FIG. 2 illustrates exemplary configurations of a base station according to one embodiment.

[0018] FIG. 3a is a drawing illustrating an exemplary configuration of an FWA device according to one embodiment.

[0019] FIG. 3b is a diagram illustrating interference associated with a second base station according to one embodiment.

[0020] FIG. 4 is a diagram illustrating a method in which an FWA device according to one embodiment transmits capability information to a first base station.

[0021] FIG. 5 is a diagram illustrating a method for a first base station and an FWA device according to one embodiment to identify interference associated with a second base station and adjust the MCS level.

[0022] FIG. 6 illustrates a method for an FWA device according to one embodiment to determine whether the failure of reception of PDSCH is based on interference associated with a second base station.

[0023] FIG. 7 illustrates a method for an FWA device according to one embodiment to determine whether the failure of reception of PDSCH is based on interference associated with a second base station using a minimum SINR value.

[0024] FIG. 8 illustrates a method for enabling or disabling reporting for interference management using DCI according to one embodiment.

[0025] FIG. 9 is a diagram illustrating a method for retransmitting PDSCH according to one embodiment.

[0026] FIG. 10a illustrates a method for performing a handover for interference management according to one embodiment.

[0027] FIG. 10b illustrates a general handover according to one embodiment.

[0028] FIG. 11 illustrates a method for eliminating interference by stopping the use of a transmission beam of a second base station that causes interference according to one embodiment.

[0029] FIG. 12 illustrates a method for determining whether a target base station can change a transmission beam according to one embodiment.

[0030] FIG. 13 illustrates a method for changing the receiving beam of an FWA device according to one embodiment.

[0031] FIG. 14 illustrates a method for eliminating interference associated with a second base station through cooperative scheduling between base stations according to one embodiment.

[0032] In relation to the description of the drawings, the same or similar reference numerals may be used for identical or similar components.

[0033] Hereinafter, various embodiments of the present invention are described with reference to the accompanying drawings. However, this is not intended to limit the present invention to specific embodiments and should be understood to include various modifications, equivalents, and / or alternatives of the embodiments of the present invention.

[0034] When downlink data to be transmitted to a UE (user equipment) (e.g., FWA device) is generated, a base station (e.g., gNB (next generation node B)) can allocate downlink data to a wireless resource. For example, downlink data (e.g., PDSCH (Physical Downlink Shared Channel)) can be transmitted from the base station to the terminal based on downlink control information (e.g., DCI (Downlink Control Information)). At this time, the DCI can be transmitted through the downlink physical control channel, PDCCH (Physical Downlink Control Channel). The terminal (e.g., FWA device) can decode the PDSCH data based on the information in the DCI and transmit a HARQ (hybrid automatic repeat request) ACK (Acknowledgement) to the base station regarding the success or failure of the decoding. For example, if the decoding is successful, the terminal (e.g., FWA device (120)) can transmit an ACK to the base station, and if it fails, it can transmit a NACK.

[0035] According to one embodiment, when determining the MCS, which is one of the pieces of information transmitted to the DCI, the base station may determine the MCS by estimating the SINR through the CQI (channel quality indicator) fed back by the terminal and its own algorithm. If the predicted SINR, which serves as the basis for the scheduled MCS, differs significantly from the actual SINR at the time of decoding by the terminal, the probability of data transmission failure may increase. When the base station estimates the terminal's SINR, HARQ ACK / NACK information may be used because the CQI feedback information is not updated every slot but is updated periodically. For example, upon receiving a HARQ ACK, the base station may allocate the MCS by increasing the predicted SINR by x. As another example, upon receiving a HARQ NACK, the base station may allocate the MCS by decreasing the predicted SINR by y. The MCS adjustment process described above may be referred to as link adaptation.

[0036] 5G NR mm-wave wireless interfaces may include bandwidth that provides higher data throughput compared to 4G (generation) LTE (long term evolution) wireless interfaces. To utilize the high bandwidth of these 5G NR wireless interfaces, telecommunications service providers may deploy fixed wireless access (FWA) devices to provide internet services including VoIP, video streaming, real-time gaming, and / or internet browsing. Thus, instead of wired electrical connections (e.g., coaxial cable connections) or optical connections (e.g., optical network terminals connected to fiber optics), FWA devices (e.g., FWA device (120) of FIG. 1) may be connected to a network via one or more base stations through wireless OTA signals. FWA devices may operate as UE devices in relation to one or more base stations. Thus, FWA devices may be installed at fixed locations within customer premises, such as homes, apartments, or offices associated with the customer.

[0037] The signal strength experienced by an FWA device at a specific location can be increased by placing a repeater device between the FWA device and a 5G NR base station. The repeater device can extend the transmission range of the wireless signal. The repeater device can receive a wireless signal from the base station, amplify the received wireless signal, and then rebroadcast the amplified wireless signal toward the FWA device. Similarly, the repeater device can receive a wireless signal from the FWA device, amplify the received wireless signal, and then rebroadcast it toward the base station.

[0038] As described above, a 5G NR radio interface can be implemented as an antenna array having multiple controllable antenna elements. The antenna array of a 5G NR base station can generate multiple antenna beams directed simultaneously toward multiple user devices using spatial multiplexing and / or beamforming. Antenna beams may correspond to radiation patterns focused in a specific direction. The optimal antenna array configuration for a specific UE device can form antenna beams directed toward the location of that specific UE device so that the specific UE device receives the signal at maximum available signal power and / or quality, while minimizing interference to other UE devices served by the base station sector associated with the antenna array radio transceiver. For example, if a base station sector serves M UE devices, the antenna array can form up to M simultaneous antenna beams. Specific antenna beams can be generated by logically grouping multiple antenna array elements and applying phase shifts to the antenna array elements to create an antenna beam pattern.

[0039] The repeater device may need to select the optimal available antenna beam to enable communication between the FWA device and the 5G NR base station. For example, the repeater device may not be able to determine the antenna beam that the FWA device can use to communicate with the 5G NR base station. As another example, the FWA device may be associated with signal strength and / or quality requirements measured by one or more key performance indicators (KPIs), and the repeater device may need to select an antenna beam that meets these requirements.

[0040] The present disclosure relates to Fixed Wireless Access (FWA) technology. In particular, the present disclosure relates to a field of technology that enables fixed broadband access using radio frequencies by utilizing 5G or 4G LTE technology. FWA technology is effective for providing internet services in areas where building wired networks is difficult or expensive, and can also be used to complement or replace existing wired networks.

[0041] In the FR2 mmWave band, FWA devices can have the following characteristics. FWA devices are primarily CPE (Customer Premises Equipment) type terminals installed externally, and because they exist in fixed locations, channel fluctuations may be minimal. Additionally, since FWA devices consume a large amount of data compared to conventional mobile terminals, interference—whether giving or receiving—can cause problems in data processing. Because FWA devices generally use analog beamforming technology, they have a narrow beamwidth and do not experience significant interference. However, FWA devices may still experience significant interference depending on the allocation results of adjacent cells.

[0042] FIG. 1 illustrates a wireless communication system according to one embodiment.

[0043] Referring to FIG. 1, the wireless communication system (100) may include a carrier network (170), a wireless access network (140), a repeater device (125) and / or a CPE (customer premises equipment) network (110).

[0044] According to one embodiment, a carrier network (170) within a wireless communication system (100) may be connected to a wireless access network (140). For example, the carrier network (170) may be connected to the wireless access network (140) to provide various services to mobile terminals (e.g., UE (user equipment)).

[0045] According to one embodiment, a wireless access network (140) may be connected to a CPE network (110) through a plurality of base stations. For example, the plurality of base stations may include a 4G base station (150) supporting 4G (generation) and / or a first base station (160) supporting 5G. For example, the 4G base station (150) may include an eNodeB (EUTRAN (evolved UMTS Terrestrial Radio Access Network) node B), and the first base station (160) may include a gNB (next generation node B).

[0046] According to one embodiment, the CPE network (110) may include a Layer 2 and / or Layer 3 LAN (local area network) associated with a customer's home. For example, the CPE network (110) may be located in a house, apartment, school, commercial office building, shopping mall, connected public transportation vehicle (e.g., bus, train, airplane, ship, etc.) and / or other types of locations associated with a customer of a telecommunications service provider.

[0047] According to one embodiment, the CPE network (110) can receive one or more services, such as TV services, internet services, and / or voice communication (e.g., telephone) services, through a wireless connection between the FWA device (120) and the operator network (170). For example, the CPE network (110) may be implemented as a gigabit network that enables a gigabit speed connection. For example, the CPE network (110) may include an FWA device (120), a CPE controller (130), a first Wi-Fi AP (access point) (132-A), ..., a second Wi-Fi AP (132-M), and / or a first mobile terminal (134-A), ..., a third mobile terminal (134-N).

[0048] According to one embodiment, the FWA device (120) may be installed at a specific location inside or outside the customer's home (e.g., outside the building, on the roof, on an exterior wall, attached to a window, etc.) or inside the building (e.g., next to a window or at a location associated with good wireless signal reception). For example, the FWA device (120) may be configured to be connected to and communicate with a wireless access network (140) and may be identified as a UE (user equipment) by the wireless access network (140). For example, the FWA device (120) may be configured to communicate via an LTE (long term evolution) wireless interface and a 5G NR (new radio) wireless interface. For example, the FWA device (120) may establish a communication connection with a 4G base station (150) via the LTE wireless interface and establish a communication connection with a first base station (160) via the 5G NR wireless interface.

[0049] According to one embodiment, the CPE controller (130) may include a network device configured to operate as a switch and / or router of a device within the CPE network (110). For example, the CPE controller (130) may connect devices of the CPE network (110) (e.g., a first Wi-Fi AP (132-A), ..., a second Wi-Fi AP (132-M)) to an FWA device 120. For example, the CPE controller (130) may include a Layer 2 and / or Layer 3 network device such as a switch, router, firewall and / or gateway, and may support an Ethernet interface, a Wi-Fi interface, a MOCA interface and / or other types of interfaces. For example, the CPE controller (130) can manage mobile terminals (134) (e.g., first mobile terminal (134-A), ..., Nth mobile terminal (134-N)) connected to the first Wi-Fi AP (132-A), ..., and the Mth Wi-Fi AP (132-M).

[0050] According to one embodiment, the Wi-Fi AP (132) may include a transceiver configured to communicate with mobile terminals (134) using a wireless LAN network based on the IEEE 802.11 standard. For example, the Wi-Fi AP (132) may enable the mobile terminals (134) to communicate with each other or the mobile terminals (134) to communicate with the FWA device (120) through the CPE controller (130). For example, the Wi-Fi AP (132) may be connected to the CPE controller (130) via a wired connection (e.g., an Ethernet cable). Additionally, the Wi-Fi AP (132) may include one or more Ethernet ports for connecting the mobile terminals (134) via a wired Ethernet connection.

[0051] In the present disclosure, the FWA device (120), CPE controller (130), and Wi-Fi AP (132) are described separately, but this is merely an example, and the FWA device (120) can perform at least some of the functions of the CPE controller (130) and / or the Wi-Fi AP (132).

[0052] According to one embodiment, mobile terminals (134) may include devices connected to a Wi-Fi AP (132) via a Wi-Fi communication method. For example, mobile terminals (134) may include portable wireless communication devices (e.g., mobile phones, smartphones, etc.), wearable computer devices, GPS (global positioning system) devices, laptop computers, tablet computers, desktop computers, set-top boxes, smart TVs, home appliances, and / or other computer devices with wireless communication capabilities.

[0053] In FIG. 1 of the present disclosure, mobile terminals (134) are described as being connected to a Wi-Fi AP (132), but this is merely an example. For example, a CPE network (110) may include fixed terminals, and the fixed terminals may be connected to a Wi-Fi AP (132).

[0054] FIG. 2 illustrates exemplary configurations of a base station according to one embodiment.

[0055] Referring to FIG. 2, an exemplary functional configuration of a first base station (160) that communicates with an FWA device (120) according to one embodiment is illustrated. The first base station (160) may include an antenna (211), a filter (212), an RF (radio frequency) processing unit (213), and / or a processor (or controller) (214).

[0056] According to one embodiment, the antenna (211) may include a plurality of antennas (or antenna elements). The antenna may perform functions for transmitting and receiving signals over a wireless channel. The antenna may include a radiator made of a conductor or a conductive pattern formed on a substrate (e.g., PCB). The antenna may radiate an upconverted signal over a wireless channel or acquire a signal radiated by another device. Each antenna may be referred to as an antenna element. In some embodiments, the antenna (211) may include an antenna array (e.g., a sub-array) in which a plurality of antenna elements form an array. The antenna (211) may be electrically connected to a filter (212) via RF signal lines. The antenna (211) may be mounted on a PCB containing a plurality of antenna elements. The PCB may include a plurality of RF signal lines connecting each antenna element to the filter of the filter (212). These RF signal lines may be referred to as a feeding network. The antenna (211) can provide a received signal to a filter (212) or radiate a signal provided from the filter (212) into the air. An antenna of the structure according to one embodiment of the present disclosure may be included in the antenna (211).

[0057] According to one embodiment, the antenna (211) may include at least one antenna module having a dual-polarized antenna. The dual-polarized antenna may be, for example, a cross-pole (x-pol) antenna. The dual-polarized antenna may include two antenna elements corresponding to different polarizations. For example, the dual-polarized antenna may include a first antenna element having a polarization of +45° and a second antenna element having a polarization of -45°. Of course, the polarization may be formed with other orthogonal polarizations (e.g., +90°, -90°) in addition to +45° and -45°. Each antenna element may be connected to a feeding line and electrically connected to a filter (212), an RF processing unit (213), and a processor (214) described later.

[0058] According to one embodiment, the dual-polarized antenna may be a patch antenna (or a microstrip antenna). Since the dual-polarized antenna has the form of a patch antenna, it can be easily implemented and integrated into an array antenna. Two signals having different polarizations may be input to each antenna port. Each antenna port corresponds to an antenna element. For high efficiency, it is required to optimize the relationship between the co-pol and cross-pol characteristics between two signals having different polarizations. In the dual-polarized antenna, the co-pol characteristic represents the characteristics for a specific polarization component, and the cross-pol characteristic represents the characteristics for a polarization component different from the specific polarization component.

[0059] An antenna (e.g., antenna element, sub array, antenna array) of an antenna device including a separable PCB according to one embodiment of the present disclosure may be included in the antenna (211). For example, a first conductive member or a first conductive member and a second conductive member of an antenna device according to one embodiment of the present disclosure may mean an antenna element and may be included in the antenna (211) of FIG. 2.

[0060] According to one embodiment, the filter (212) may perform filtering to transmit a signal of a desired frequency. The filter (212) may perform the function of selectively identifying a frequency by forming resonance. In one embodiment, the filter (212) may form resonance through a cavity that structurally contains a dielectric. Additionally, in some embodiments, the filter (212) may form resonance through elements that form inductance or capacitance. Additionally, in some embodiments, the filter (212) may include an elastic filter such as a bulk acoustic wave (BAW) filter or a surface acoustic wave (SAW) filter. The filter (212) may include at least one of a band pass filter, a low pass filter, a high pass filter, or a band reject filter. That is, the filter (212) may include RF circuits for obtaining a signal in a frequency band for transmission or a frequency band for reception. A filter (212) according to various embodiments can electrically connect the antenna (211) and the RF processing unit (213).

[0061] According to one embodiment, the RF processing unit (213) may include a plurality of RF paths. An RF path may be a unit of a path through which a signal received through an antenna or a signal radiated through an antenna passes. At least one RF path may be referred to as an RF chain. An RF chain may include a plurality of RF elements. RF elements may include an amplifier, a mixer, an oscillator, a digital-analog converter (DAC), an analog-digital converter (ADC), etc. For example, the RF processing unit (213) may include an up converter that up-converts a baseband digital transmission signal to a transmission frequency, and a DAC that converts the up-converted digital transmission signal into an analog RF transmission signal. The up converter and the DAC form part of a transmission path. The transmission path may further include a power amplifier (PA) or a coupler (or combiner). Additionally, for example, the RF processing unit (213) may include an analog-to-digital converter (ADC) that converts an analog RF reception signal into a digital reception signal and a down converter that converts the digital reception signal into a baseband digital reception signal. The ADC and the down converter form part of the reception path. The reception path may further include a low-noise amplifier (LNA) or a coupler (or divider). The RF components of the RF processing unit may be implemented on a PCB. The antennas and the RF components of the RF processing unit may be implemented on a PCB, and filters may be repeatedly connected between the PCBs to form multiple layers.

[0062] The RFIC (radio frequency integrated circuit) and package board (PKG) of an antenna device including a separable PCB according to one embodiment of the present disclosure may be included in the RF processing unit (213) of FIG. 2. That is, the RF processing unit (213) may include an RFIC (radio frequency integrated circuit) as an RF device for mmWave. As described above in the present disclosure, the RFIC may be formed as an RFIC chip combined with a package board and coupled to the first PCB, or the RFIC may be directly coupled to the first PCB.

[0063] The processor (214) can control the overall operations of the base station (160). The processor (214) may include various modules for performing communication. The processor (214) may include at least one processor, such as a modem. The processor (214) may include modules for digital signal processing. For example, the processor (214) may include a modem. When transmitting data, the processor (214) generates complex symbols by encoding and modulating the transmitted bit sequence. Also, for example, when receiving data, the processor (214) restores the received bit sequence by demodulating and decoding the baseband signal. The processor (214) can perform the functions of a protocol stack required by the communication standard.

[0064] FIG. 3a is a drawing illustrating an exemplary configuration of an FWA device according to one embodiment.

[0065] Referring to FIG. 3a, an FWA device (120) according to one embodiment may include at least one processor (310) (e.g., processor (214) of FIG. 2), at least one transceiver (320), and / or at least one antenna (330).

[0066] According to one embodiment, at least one processor (310) may include at least one communication processor (e.g., a baseband processor). For example, at least one processor (310) may be electrically connected to at least one transceiver (320) and may generate or process a signal (e.g., a baseband signal).

[0067] For example, at least one processor (310) can transmit a signal (e.g., BB signal) to at least one transceiver (320) or receive a signal (e.g., BB signal) from at least one transceiver (320).

[0068] According to one embodiment, at least one transceiver (320) can be electrically connected to at least one antenna (330).

[0069] According to one embodiment, at least one transceiver (320) can upconvert a BB signal transmitted from at least one processor (310) into an IF (intermediate frequency) signal, upconvert the IF signal into a RF (radio frequency) signal, and transmit the RF signal to at least one antenna (330). As another example, at least one transceiver (320) can receive an RF signal from at least one antenna (330), downconvert the RF signal into an IF signal or a BB signal, and transmit the IF signal or the BB signal to at least one processor (310).

[0070] According to one embodiment, at least one transceiver (320) may include at least one transmitter and / or at least one receiver. For example, at least one transceiver (320) may include a first transceiver including a first transmitter and a first receiver, and at least one transceiver (320) may include a second transceiver including a first transmitter.

[0071] According to one embodiment, at least one transceiver (320) can process, transmit, and / or receive RF signals of various frequency bands. For example, a first transceiver and a second transceiver included in at least one transceiver (320) can each process RF signals of a first frequency band. For example, the first transceiver included in at least one transceiver (320) can process RF signals of a first frequency band, and the second transceiver can process RF signals of a second frequency band. For example, the second frequency band may partially overlap with the first frequency band.

[0072] According to one embodiment, at least one antenna (330) may include various types of antennas. For example, at least one antenna (330) may include a patch antenna, a dipole antenna, a monopole antenna, a slit antenna, an LDS (laser direct structuring) antenna, and / or an IFA (inverted-F antenna).

[0073] For example, at least one antenna (330) may include an antenna for transmitting and / or receiving a signal in the mmWave frequency band. For example, at least one antenna (330) may include a plurality of antenna elements (e.g., patch antennas), and the plurality of antenna elements may form an array. The plurality of antenna elements forming the array may transmit and / or receive a signal in the mmWave frequency band.

[0074] In the present disclosure, the term "at least one processor" (310) may be replaced with other terms referring to a configuration for data processing. For example, the term "at least one processor" may be replaced with a controller or a computing device.

[0075] In the present disclosure, at least one transceiver (320) may include a radio frequency integrated circuit (RFIC), a front-end module (RF-FEM), and / or an intermediate frequency integrated circuit (IFIC). For example, in FIG. 3, at least one transceiver (320) is described as including an RFIC and an IFIC, but this is merely an example and at least one transceiver (320) may correspond to an RFIC. As another example, at least one transceiver (320) may correspond to an IFIC.

[0076] FIG. 3b is a diagram illustrating interference associated with a second base station according to one embodiment.

[0077] Referring to FIG. 3b, a first graph (351) according to one embodiment represents the signal-to-interference-plus-noise ratio (SINR) value of a signal expected by the first base station (160). For example, the first base station (160) can establish a communication connection with the FWA device (120) and transmit first signals. In this case, the first base station (160) can expect the SINR value of the first signals as a value indicating the communication status between the first base station (160) and the FWA device (120). For example, the first base station (160) can estimate the expected SINR value based on feedback information received from the FWA device (120).

[0078] According to one embodiment, the second graph (352) represents the SINR value of the signal actually received by the FWA device (120). There may be a difference between the expected SINR value (hereinafter, expected SINR value) based on the communication status between the first base station (160) and the FWA device (120) and the SINR value of the signal actually received by the FWA device (120) (hereinafter, actual SINR value).

[0079] According to one embodiment, SINR values ​​predicted by the first base station (160) may be changed based on SINR values ​​of the signal actually received by the FWA device (120). For example, the first base station (160) may identify that the actual SINR values ​​(370) are lower than the predicted SINR values ​​(360) within the first interval (381). In this case, the first base station (160) may lower the predicted SINR values ​​(360) based on the decrease in the actual SINR values ​​(370).

[0080] For example, the first base station (160) can confirm that the first actual SINR value (371) (e.g., about 4 dB) is lower than the first expected SINR value (361) (e.g., about 9 dB) in the first section (381), and the first base station (160) can lower the expected SINR value to the second expected SINR value (362) (e.g., about 8.5 dB). Lowering the expected SINR value by the first base station (160) can be substantially referred to as lowering the modulation coding scheme (MCS) level, and when the MCS level is lowered, the data throughput between the first base station (160) and the FWA device (120) may be lowered.

[0081] For example, the first base station (160) can confirm that the second actual SINR value (372) (e.g., about 4 dB) is lower than the second expected SINR value (362) (e.g., about 8.5 dB) in the first interval (381), and the first base station (160) can lower the expected SINR value to the third expected SINR value (363) (e.g., about 8 dB) in the next slot. Lowering the expected SINR value by the first base station (160) can be substantially referenced as lowering the MCS level, and when the MCS level is lowered, the data throughput between the first base station (160) and the FWA device (120) can be lowered.

[0082] For example, the first base station (160) can identify that the third actual SINR value (373) (e.g., about 4 dB) is lower than the third expected SINR value (363) (e.g., about 8 dB) in the first section (381), and can lower the expected SINR value and MCS level of the next slot. For example, the first base station (160) can identify that the fourth actual SINR value (374) (e.g., about 4 dB) is lower than the fourth expected SINR value (364) (e.g., about 7.5 dB) in the first section (381), and can lower the expected SINR value and MCS level of the next slot.

[0083] As a result, due to the difference between the expected SINR values ​​(360) and the actual SINR values ​​(370), the MCS level applied to communication between the first base station (160) and the FWA device (120) may be lowered, and the data throughput may also be reduced.

[0084] According to one embodiment, the cause of the actual SINR values ​​(370) being lower than the expected SINR values ​​(360) may include a change in the communication state between the first base station (160) and the FWA device (120) (e.g., presence of an obstacle) or instantaneous interference caused by another base station (e.g., second base station).

[0085] If the cause of the actual SINR values ​​(370) being lower than the expected SINR values ​​(360) is instantaneous interference caused by another base station, the degradation of communication performance (e.g., SINR value) due to interference may be relatively temporary compared to other causes. For example, instantaneous interference may refer to a case where another base station (e.g., a second base station) performs communication using a cell adjacent to the cell for communication between the first base station (160) and the FWA device (120). Since interference caused by another base station (e.g., a second base station) performing communication using an adjacent cell may be temporary or irregular, the instantaneous interference caused by this may also be relatively temporary compared to other interferences.

[0086] Accordingly, the first base station (160) may not lower the expected SINR values ​​(360) even if there is a difference between the expected SINR values ​​(360) and the actual SINR values ​​(370) when the cause of the decrease in the expected SINR values ​​(360) is instantaneous interference (e.g., interference associated with the second base station). Through this, the first base station (160) can reduce or minimize the unnecessary decrease in data throughput between the first base station (160) and the FWA device (120) caused by the MCS level being lowered due to temporary interference.

[0087] Consequently, the first base station (160) and / or the FWA device (120) need to identify whether the cause of the decrease is interference (e.g., instantaneous interference) associated with the second base station when the actual SINR values ​​(370) are lower than the expected SINR values ​​(360) in order to prevent a situation where the data throughput is unnecessarily lowered.

[0088] In FIGS. 4 through 14 below, a method is described in which a first base station (160) and / or an FWA device (120) identifies interference (e.g., instantaneous interference) associated with a second base station and performs communication or eliminates interference using the identified interference. For example, a method is described in which a first base station (160) and / or an FWA device (120) identifies transmission failures caused by interference (e.g., instantaneous interference) associated with a second base station and improves throughput performance. For example, a method is described in which a first base station (160) and / or an FWA device (120) identifies transmission failures caused by interference (e.g., instantaneous interference) associated with a second base station and avoids or controls so that interference associated with the second base station does not occur in a subsequent time domain (e.g., slot).

[0089] The instantaneous interference of the present disclosure may be referred to as interference that occurs as a second base station uses resource blocks (RBs) adjacent to or at least partially overlapping RBs for communication between the first base station (160) and the FWA device (120). As another example, the instantaneous interference may be referred to as interference that occurs as a cell adjacent to a cell used for data transmission and / or reception between the first base station (160) and the FWA device (120).

[0090] FIG. 4 is a diagram illustrating a method in which an FWA device according to one embodiment transmits capability information to a first base station.

[0091] Referring to FIG. 4, an FWA device (120) according to one embodiment can transmit capability information to a first base station (160). For example, the UE (user equipment) can be distinguished as a mobile terminal and / or a fixed FWA device (120). The FWA device (120) can transmit capability information to the first base station (160) indicating that the FWA device (120) is a device (e.g., an FWA device) that is distinguished from a mobile terminal.

[0092] For example, the first base station (160) needs to identify whether the device with which the communication connection has been established (e.g., FWA device (120)) is a mobile terminal or an FWA device (120) in order to determine whether to manage or identify (or detect) interference (e.g., instantaneous interference) associated with the second base station. Accordingly, the FWA device (120) can transmit capability information indicating the UE type (e.g., FWA type) to the first base station (160).

[0093] According to one embodiment, in step 401, the first base station (160) may transmit a message for capability inquiry to the FWA device (120) to receive capability information. For example, the first base station (160) may transmit a message requesting information about the capability of the FWA device (120) when the FWA device (120) is camped on to the cell of the first base station (160) by performing a random access procedure. For example, the first base station (160) may transmit a message requesting information about the capability randomly when the FWA device (120) is in a radio resource control (RRC) connection state.

[0094] According to one embodiment, the FWA device (120) may transmit a message (e.g., capability information) containing information about the UE type in response to a message for capability inquiry in step 403. For example, the FWA device (120) may transmit information to the first base station (160) indicating whether it is a general UE (e.g., mobile terminal) or an FWA terminal (e.g., fixed UE). For example, the FWA device (120) may transmit an indicator to the first base station (160) indicating the type of the FWA device (120).

[0095] [Table 1] may be an example of a UE type report that the FWA device (120) transmits to the first base station (160).

[0096]

[0097] According to one embodiment, the first base station (160) can identify the FWA device (120) as an FWA device that is distinguished from a mobile terminal based on receiving a message containing information about the UE type (e.g., UE type report).

[0098] According to one embodiment, in step 405, the first base station (160) may transmit an RRC message to the FWA device (120) containing configuration information for the FWA device (120) based on information about the UE type. For example, the RRC message may include information about the type of the FWA device (120). For example, the RRC message may include configuration information for the FWA device (120) (e.g., information for interference management associated with the second base station). For example, the information for interference management associated with the second base station may include an indicator indicating whether to perform interference management and / or information about a threshold value for interference management.

[0099] In the present disclosure, it is described that the first base station (160) transmits a message for a capability inquiry to receive capability information, but this is merely an example. For example, even if the first base station (160) does not transmit a message for a capability inquiry, the FWA device (120) can transmit capability information for a UE type report to the first base station (160).

[0100] The FWA device (120) of the present disclosure has been described using the term FWA device for convenience of explanation, but may be replaced with the term UE (user equipment). As another example, the FWA device (120) may be replaced with the terms UE, fixed UE, device, apparatus, and / or relay device.

[0101] FIG. 5 is a diagram illustrating a method for a first base station and an FWA device according to one embodiment to identify interference associated with a second base station and adjust the MCS level.

[0102] Figure 5 below describes a method in which a first base station (160) and / or an FWA device (120) identifies interference (e.g., instantaneous interference) associated with a second base station and performs link adaptation for adjusting the MCS level.

[0103] Referring to FIG. 5, in one embodiment, the first base station (160) may transmit configuration information for reporting for interference management to the FWA device (120) via RRC signaling in step 501. For example, the configuration information may include information about the type of the FWA device (120). For example, the configuration information may include an indicator indicating whether to perform a report (or UCI report) for the management of interference (e.g., instantaneous interference) associated with the second base station. For example, the configuration information may include information about a threshold value (e.g., SINR gap) for identifying interference (e.g., instantaneous interference) associated with the second base station.

[0104] [Table 2] is an example of configuration information included in an RRC message.

[0105]

[0106] For example, in [Table 2], InterferenceManagementInformation may be referenced as information for interference management associated with the second base station. For example, in [Table 2], Indicator may be referenced as an indicator indicating whether to perform reporting for interference management. For example, if Indicator is true, the FWA device (120) may perform collection and reporting of information for interference management (e.g., UCI reporting). For example, if Indicator is false, the FWA device (120) may not perform collection and reporting of information for interference management.

[0107] For example, in [Table 2], Threshold may be a threshold value for identifying whether the cause (or interference) of the difference between the expected SINR value and the actual SINR value is based on interference (e.g., instantaneous interference) associated with the second base station.

[0108] According to one embodiment, the FWA device (120) may determine whether to perform a report for interference management associated with the second base station based on configuration information. For example, if an indicator included in the received configuration information indicates a report for interference management (e.g., UCI report), the FWA device (120) may perform a report for interference management as described in steps 509 and 513 below, and may collect (or identify) information for reporting (e.g., average SINR value, real-time SINR value, minimum SINR value, maximum SINR value) to perform the report for interference management.

[0109] For example, the FWA device (120) can determine whether to perform a report for interference management based on configuration information and a MAC (medium access control) CE (control element). For example, the FWA device (120) may be configured to perform a report for interference management when an indicator included in the received configuration information indicates a report for interference management (e.g., when the indicator is true). However, the FWA device (120) may collect information for reporting (e.g., average SINR value, real-time SINR value, minimum SINR value, maximum SINR value) and perform a report only when it receives a MAC CE from the first base station (160) that additionally enables reporting, even when an RRC setting for interference management is set. In this case, if the FWA device (120) receives a MAC CE from the first base station (160) that disables the interference management report while performing the interference management report, it may stop (or disable) the collection and reporting of information for the report (e.g., average SINR value, real-time SINR value, minimum SINR value, maximum SINR value).

[0110] As another example, the FWA device (120) may perform a report for interference management when an indicator included in the received configuration information directs a report for interference management (e.g., when the indicator is set to true). However, the FWA device (120) may stop the report for interference management if it receives a MAC CE that disables the report while performing the report for interference management. In this case, the FWA device (120) may subsequently receive a MAC CE that enables the report and perform the report for interference management. That is, the first base station (160) can turn on / off the report for interference management and information collection using the MAC CE.

[0111] According to one embodiment, the first base station (160) may transmit a first physical downlink shared channel (PDSCH) to the FWA device (120) in step 503. For example, the first base station (160) may transmit downlink control information (DCI) scheduling the first PDSCH to the FWA device (120) on a physical downlink control channel (PDCCH). The first base station (160) may transmit data on the PDSCH to the FWA device (120) based on the DCI.

[0112] According to one embodiment, the FWA device (120) may transmit a first uplink control information (UCI) containing HARQ information for the PDSCH in step 505. For example, if the FWA device (120) succeeds in receiving the PDSCH, it may transmit a first UCI containing an acknowledgment (ACK) indicating to the first base station (160) that the PDSCH has been successfully received. In this case, the first base station (160) that receives the ACK may increase the MCS level. For example, the first base station (160) may increase the MCS level from 10 to 11. (Perform link adaptation)

[0113] According to one embodiment, the first base station (160) may transmit the second PDSCH in step 507. For example, the first base station (160) may transmit a DCI for scheduling the second PDSCH to the FWA device (120) and transmit the second PDSCH to the FWA device (120) based on the DCI. For example, unlike the first PDSCH, the second PDSCH may be transmitted with the MCS level at 11.

[0114] According to one embodiment, the FWA device (120) may transmit a second UCI to the first base station (160) in step 509, which includes HARQ information for the second PDSCH and / or an indicator indicating whether there is interference (e.g., instantaneous interference) associated with the second base station. For example, the FWA device (120) may fail to receive the second PDSCH transmitted by the first base station (160). In this case, the FWA device (120) may transmit a second UCI to the first base station (160), which includes a negative-ACK (NACK) information indicating that there was a failure to receive the second PDSCH, and an indicator (e.g., an instantaneous interference flag (IIF)) indicating whether the failure to receive is based on interference (e.g., instantaneous interference) associated with the second base station.

[0115] For example, the UCI may include a 1-bit indicator (or, a 1-bit field) (e.g., an IIF field) that indicates whether the failure of reception is based on interference associated with a second base station.

[0116] For example, if the failure to receive the second PDSCH is based on interference associated with the second base station (e.g., instantaneous interference), the bit value of the indicator may be 1 (or true). If the failure to receive the second PDSCH is not based on interference associated with the second base station, the bit value of the indicator may be 0 (or false).

[0117] According to one embodiment, the FWA device (120) can identify (or determine) whether the failure to receive the second PDSCH is based on instantaneous interference, based on a threshold value (e.g., SINR gap) included in the setting information and collected information (e.g., average SINR, real-time SINR, minimum SINR value, maximum SINR value). A specific method for the FWA device (120) to identify whether instantaneous interference has occurred is described below in FIGS. 6 and 7.

[0118] According to one embodiment, the first base station (160) can identify that the received NACK and indicator (e.g., IIF indicator) are 0 and that the failure of transmission of the second PDSCH was not based on instantaneous interference. In this case, the first base station (160) can lower the MCS from 11 to 10 for data transmission in step 510.

[0119] For example, if IIF is False, the first base station (160) may determine that the failure of the second PDSCH transmission occurred not due to instantaneous interference but due to an incorrect result of link adaptation, and may lower the MCS level from 11 to 10.

[0120] According to one embodiment, the first base station (160) can transmit the third PDSCH to the FWA device (120) in step 511.

[0121] According to one embodiment, the FWA device (120) can identify a failure in receiving the third PDSCH. The FWA device (120) can transmit a third UCI containing a NACK and / or an indicator (e.g., an IIF indicator) indicating a failure in receiving the third PDSCH to the first base station (160) in step 513. In this case, the FWA device (120) can identify that the failure in receiving the third PDSCH is based on interference (e.g., instantaneous interference) associated with the second base station based on a SINR value and a threshold value before transmitting the indicator. Accordingly, the FWA device (120) can transmit to the first base station (160) the value of the indicator (e.g., an IIF indicator) transmitted along with the NACK to be set to 1 (or true).

[0122] According to one embodiment, the first base station (160) can determine the MCS level based on the NACK and indicator (e.g., IIF indicator) received in step 514. For example, the first base station (160) can maintain the MCS level at 10 based on the indicator even though the NACK has been received. For example, the first base station (160) can identify that the transmission of the third PDSCH failed upon receiving the NACK, but the cause of the transmission failure is interference associated with the second base station (e.g., instantaneous interference). In this case, the first base station (160) can maintain the MCS level without lowering it.

[0123] If the transmission failure of the third PDSCH is based on instantaneous interference rather than other factors (e.g., changes in channel environment), the transmission failure may be temporary, and there may be no need to lower the MCS level to the extent of lowering data throughput. Accordingly, the first base station (160) may maintain the MCS level at 10 to maintain data throughput even if the third PDSCH is not delivered to the FWA device (120).

[0124] For example, if IIF is True, the first base station (160) can determine that the failure of the second PDSCH transmission was not caused by an incorrect link adaptation result and can maintain the MCS.

[0125] According to one embodiment, the first base station (160) may transmit a fourth PDSCH to the FWA device (120) at step 515. If the FWA device (120) succeeds in receiving the fourth PDSCH at step 517, it may transmit a fourth UCI containing an ACK to the FWA device (120), and the first base station (160) may raise the MCS level based on the ACK information at step 518. At this time, the ACK information may not include an indicator (e.g., an IIF indicator).

[0126] However, this is merely an example, and even when ACK information is transmitted, an indicator (e.g., IIF indicator) may be included, in which case the IIF indicator may be set to 0.

[0127] In the present disclosure, an indicator (e.g., an IIF indicator) is described as being included in the UCI along with the NACK and transmitted from the FWA device (120) to the first base station (160), but this is merely an example. For example, the indicator (e.g., an IIF indicator) may be transmitted to the first base station (160) as a message separate from the UCI.

[0128] In the present disclosure, it is described that the first PDSCH, the second PDSCH, the third PDSCH, and the fourth PDSCH are transmitted sequentially to the FWA device (120), and the MCS level is adjusted accordingly. However, this is merely for convenience of explanation, and the timing and order of reception of the first to fourth PDSCHs may differ, and the reception of the first to fourth PDSCHs may be independent.

[0129] In the present disclosure, the statement that the failure of reception of PDSCH is based on interference associated with a second base station (e.g., instantaneous interference) may be referred to as substantially the failure of reception of PDSCH being due to interference associated with a second base station.

[0130] In the present disclosure, failure to receive PDSCH can substantially be referred to as the FWA device (120) failing to decode PDSCH.

[0131] Step 501 of the present disclosure may correspond to Step 405 of FIG. 4, and the description of Step 405 may be applied to Step 501 unless contradictory.

[0132] Interference associated with the second base station of the present disclosure may be referred to as instantaneous interference.

[0133] In the present disclosure, it is described that the first base station (160) transmits configuration information to the FWA device (120), but this is merely an example. For example, configuration information may be set to the FWA device (120) from a base station other than the first base station (160) (e.g., a second base station). That is, the object that sets the configuration information for reporting for interference management associated with the second base station to the FWA device (120) and the object that receives the IIF indicator may be different.

[0134] The communication between the FWA device (120) and the first base station (160) described in FIG. 5 of the present disclosure may be based on the FR (frequency range) 2 band of NR (new radio) (e.g., about 24.25 GHz or higher). However, this is merely an example and the present disclosure may also be applied to the FR1 band and / or LTE (long term evolution) band.

[0135] FIG. 6 illustrates a method for an FWA device according to one embodiment to determine whether the failure of reception of PDSCH is based on interference associated with a second base station.

[0136] Referring to FIG. 6, an FWA device (120) according to one embodiment may fail to decode a PDSCH transmitted from a first base station (160) in step 601. For example, the first base station (160) may transmit a PDSCH to the FWA device (120). The FWA device (120) may receive only a portion of the PDSCH or may not receive the PDSCH at all. In this case, the FWA device (120) may fail to decode a scheduled PDSCH.

[0137] According to one embodiment, the FWA device (120) can identify (or determine) whether the failure to receive the PDSCH (or the failure to decode the PDSCH) is based on instantaneous interference, based on identifying the failure to decode the PDSCH in step 603. For example, the FWA device (120) can determine whether the difference between the average SINR value and the current SINR value is greater than a threshold value. For example, the FWA device (120) can receive configuration information (e.g., the configuration information of step 501 of FIG. 5) for managing interference associated with the second base station from the first base station (160). The FWA device (120) can receive a MAC CE that indicates that the indicator included in the received configuration information directs reporting for interference management and enables reporting for interference management. In this case, the FWA device (120) can identify average SINR values ​​over a specified period based on signals received from the first base station (160). For example, when the collection of information for reporting (e.g., average SINR, real-time SINR) is triggered based on MAC CE, the FWA device (120) can measure slot-by-slot SINR values ​​and obtain average SINR, maximum SINR values ​​and / or minimum SINR values ​​based on the SINR values.

[0138] The FWA device (120) can identify the SINR value at the time when the failure of PDSCH reception is identified (e.g., current SINR) and can determine whether the difference between the average SINR value and the SINR value at the time when the failure is identified is greater than a threshold value (e.g., SINR gap). For example, the threshold value can be identified based on information about the threshold value included in the configuration information received in step 501 of FIG. 5.

[0139] Including information regarding a threshold value for identifying whether interference associated with the second base station has occurred in the setting information via RRC signaling is merely an example and is not limited thereto. For example, information regarding the threshold value may be set to the FWA device (120) by the first base station (160) via MAC CE and / or DCI.

[0140] According to one embodiment, the FWA device (120) can identify that the failure of PDSCH reception is not based on interference associated with the second base station (e.g., instantaneous interference) if, in step 605, the difference between the average SINR value and the current SINR value is less than or equal to a threshold value. For example, the FWA device (120) can identify that the failure of PDSCH decoding is not based on interference associated with the second base station (e.g., instantaneous interference) if the difference between the average SINR value and the current SINR value is less than or equal to a threshold value. In this case, the FWA device (120) can transmit an indicator (e.g., an indicator indicating whether the failure is based on interference associated with the second base station) along with NACK information to the first base station (160). For example, the indicator may indicate that the failure of PDSCH reception is not based on interference associated with the second base station (e.g., instantaneous interference). For example, the indicator may have a bit value of 0 (e.g., false). That is, transmitting an indicator having a bit value of 0 along with the NACK of FIG. 7 can correspond to step 509 of FIG. 5.

[0141] According to one embodiment, the FWA device (120) can identify that the failure of PDSCH reception is based on interference associated with the second base station (e.g., instantaneous interference) if, in step 607, the difference between the average SINR value and the current SINR value is greater than a threshold. For example, the FWA device (120) can identify that the failure of PDSCH decoding is due to interference associated with the second base station (e.g., instantaneous interference) if the difference between the average SINR value and the current SINR value is greater than a threshold. In this case, the FWA device (120) can transmit an indicator (e.g., an indicator indicating whether the failure is based on interference associated with the second base station) along with NACK information to the first base station (160). For example, the indicator may indicate that the failure of PDSCH reception is based on interference associated with the second base station (e.g., instantaneous interference). For example, the indicator may have a bit value of 1 (e.g., true). That is, transmitting an indicator having a bit value of 1 along with the NACK of FIG. 7 can correspond to step 513 of FIG. 5.

[0142] In FIG. 5 of the present disclosure, it is described that the FWA device (120) determines whether interference associated with the second base station has occurred and transmits an indicator (e.g., an IIF indicator) indicating whether it has occurred to the first base station (160), but this is merely an example. For example, the FWA device (120) may transmit information (e.g., average SINR value, current SINR value) to the first base station (160) to determine whether interference has occurred. In this case, the first base station (160) may determine whether the failure to receive the PDSCH is due to interference associated with the second base station based on the received information. That is, the subject determining whether interference has occurred may be the first base station (160), not the FWA device (120).

[0143] Step 603 of the present disclosure may be a step of determining whether the failure of reception is based on instantaneous interference, and as another example, a step of determining whether instantaneous interference occurred during a specified slot or interval.

[0144] Steps 601 to 603 of the present disclosure may exist between the step of receiving PDSCH and the step of transmitting an indicator (e.g., an IIF indicator) along with NACK information. For example, steps 601 to 603 may be performed between steps 507 and 509 of FIG. 5. For example, steps 601 to 603 may be performed between steps 511 and 513 of FIG. 5. However, this is merely an example, and steps 601 to 603 may exist in various orders.

[0145] In FIG. 6 of the present disclosure, it is assumed that the average SINR is the average SINR over a specified period of time, but this is merely an example. For example, the average SINR value may be the average SINR value of the RBs allocated to the FWA device (120) from the first base station (160). For example, the average SINR value may be the average SINR value of the RBs allocated to the FWA device (120) for receiving PDSCHs.

[0146] In FIG. 6 of the present disclosure, the FWA device (120) is described as identifying whether interference (e.g., instantaneous interference) associated with the second base station has occurred using SINR, but this is merely an example. For example, the FWA device (120) may identify whether interference associated with the second base station has occurred using other parameters indicating channel conditions (e.g., RSRP (reference signals received power), RSRQ (reference signal received quality), RSSI (received signal strength indicator)).

[0147] FIG. 7 illustrates a method for an FWA device according to one embodiment to determine whether the failure of reception of PDSCH is based on interference associated with a second base station using a minimum SINR value.

[0148] In FIG. 7, compared with FIG. 6, the FWA device (120) can compare the average SINR value with the minimum SINR value of the RBs associated with the second base station. For example, in the embodiment of FIG. 6, the FWA device (120) can compare the average SINR value with the current SINR value to determine whether instantaneous interference has occurred. On the other hand, in the embodiment of FIG. 7, the FWA device (120) can compare the average SINR value with the minimum SINR value of the RBs associated with the second base station to determine whether instantaneous interference has occurred.

[0149] For example, the RBs associated with the second base station may include RBs that overlap at least partially with the RBs used by the second base station among the RBs allocated by the first base station (160) for the FWA device (120). For example, the RBs associated with the second base station may include RBs adjacent to the RBs used by the second base station among the RBs allocated by the first base station (160) for the FWA device (120). For example, the RBs associated with the second base station may include RBs that overlap at least partially with the frequency band used by the second base station among the RBs allocated by the first base station (160) for the FWA device (120).

[0150] Referring to FIG. 7, an FWA device (120) according to one embodiment may fail to decode a PDSCH transmitted from a first base station (160) in step 701. For example, the first base station (160) may transmit a PDSCH to the FWA device (120). The FWA device (120) may receive only a portion of the PDSCH or may not receive the PDSCH at all. In this case, the FWA device (120) may fail to decode the scheduled PDSCH.

[0151] According to one embodiment, the FWA device (120) can identify (or determine) whether the failure to receive the PDSCH (or the failure to decode the PDSCH) is based on the failure to decode the PDSCH in step 703. For example, the FWA device (120) can determine whether the difference between the average SINR value and the minimum SINR value is greater than a threshold value. For example, the FWA device (120) can receive configuration information (e.g., the configuration information of step 501 of FIG. 5) from the first base station (160) for managing interference (e.g., instantaneous interference) associated with the second base station. The FWA device (120) can receive a MAC CE that directs a report for interference management and enables a report for interference management, which is included in the received configuration information. In this case, the FWA device (120) can identify average SINR values ​​for all assigned RBs based on signals received from the first base station (160). For example, when the collection of information for reporting (e.g., average SINR, real-time SINR) is triggered based on MAC CE, the FWA device (120) can measure SINR values ​​for each of all assigned RBs and obtain an average SINR based on the SINR values.

[0152] The FWA device (120) can obtain a minimum SINR value for RBs associated with the second base station among the RBs allocated from the first base station (160). For example, the FWA device (120) can identify RBs that are adjacent to or overlap with the RBs used by the second base station among the RBs allocated from the first base station (160). In this case, the FWA device (120) can measure a SINR value for each of the adjacent or overlapping RBs and identify a minimum SINR value among the measured SINR values.

[0153] According to one embodiment, the FWA device (120) can determine whether the difference between the average SINR value and the minimum SINR value for the RBs is greater than a threshold value (e.g., SINR gap). For example, the threshold value may be identified based on information about the threshold value included in the configuration information received in step 501 of FIG. 5.

[0154] Including information regarding a threshold value for identifying whether interference associated with the second base station has occurred in the setting information via RRC signaling is merely an example and is not limited thereto. For example, information regarding the threshold value may be set to the FWA device (120) by the first base station (160) via MAC CE and / or DCI.

[0155] According to one embodiment, the FWA device (120) can identify that the failure of PDSCH reception is not based on interference associated with the second base station (e.g., instantaneous interference) if, in step 705, the difference between the average SINR value and the minimum SINR value is less than or equal to a threshold value. For example, the FWA device (120) can identify that the failure of PDSCH decoding is not based on interference associated with the second base station (e.g., instantaneous interference) if the difference between the average SINR value and the minimum SINR value is less than or equal to a threshold value. In this case, the FWA device (120) can transmit an indicator (e.g., an indicator indicating whether the failure is based on interference associated with the second base station) along with NACK information to the first base station (160). For example, the indicator may indicate that the failure of PDSCH reception is not based on interference associated with the second base station (e.g., instantaneous interference). For example, the indicator may have a bit value of 0 (e.g., false). That is, transmitting an indicator having a bit value of 0 along with the NACK of FIG. 7 can correspond to step 509 of FIG. 5.

[0156] According to one embodiment, the FWA device (120) can identify that the failure of PDSCH reception is based on interference associated with the second base station (e.g., instantaneous interference) if the difference between the average SINR value and the minimum SINR value in step 707 is greater than a threshold value. For example, the FWA device (120) can identify that the failure of PDSCH decoding is due to interference associated with the second base station (e.g., instantaneous interference) if the difference between the average SINR value and the minimum SINR value is greater than a threshold value. In this case, the FWA device (120) can transmit an indicator (e.g., an indicator indicating whether the failure is based on interference associated with the second base station) along with NACK information to the first base station (160). For example, the indicator may indicate that the failure of PDSCH reception is based on interference associated with the second base station (e.g., instantaneous interference). For example, the indicator may have a bit value of 1 (e.g., true). That is, transmitting an indicator having a bit value of 1 along with the NACK of FIG. 7 can correspond to step 513 of FIG. 5.

[0157] FIG. 8 illustrates a method for enabling or disabling reporting for interference management using DCI according to one embodiment.

[0158] Referring to FIG. 8, a first base station (160) according to one embodiment may transmit a DCI that triggers a report for interference management to the FWA device (120) after transmitting configuration information for managing interference associated with the second base station to the FWA device (120) via RRC signaling. For example, the first base station (160) may transmit configuration information for interference management (e.g., threshold value, and / or IIF indicator) to the FWA device (120) in step 501. In this case, the IIF indicator may instruct the FWA device (120) to perform a report for interference management (e.g., UCI report).

[0159] However, even if the FWA device (120) is configured to perform reporting for interference management, it can only collect and / or store information for reporting (e.g., average SINR, real-time SINR) and perform reporting when it receives DCI from the first base station (160). For example, an FWA device (120) configured to report interference management via RRC settings can collect information for reporting and perform reporting when DCI triggers reporting. For example, an FWA device (120) configured to report interference management via RRC settings may not collect information for reporting and / or perform reporting when DCI does not trigger reporting, even if it is configured to report via RRC settings.

[0160] Comparing FIG. 5 and FIG. 8, in the embodiment of FIG. 5, the FWA device (120) can collect information for reporting based on RRC messages and MAC CE and perform reporting (e.g., UCI reporting including indicators). On the other hand, in the embodiment of FIG. 8, the FWA device (120) can collect information for reporting based on RRC messages and DCI and perform reporting (e.g., UCI reporting).

[0161] According to one embodiment, the DCI transmitted in step 802 may include a field that triggers a UCI report containing information for scheduling the first PDSCH and / or an IIF indicator.

[0162] For example, [Table 3] is an example of fields and / or thresholds for triggering UCI reporting that includes IIF indicators included in DCI.

[0163]

[0164] According to one embodiment, when the instantaneous interference triggering flag is 0 (e.g., true), the FWA device (120) may begin collecting information (e.g., average SINR) to report an IIF indicator and transmit it to the first base station (160) by including the IIF indicator in the UCI. For example, when the instantaneous interference triggering flag is 1 (e.g., false), the FWA device (120) may not perform the report even though it is set to report the IIF indicator via an RRC message.

[0165] According to one embodiment, the threshold value included in the DCI may be a value transmitted in place of the threshold value included in the setting information of step 501, or a value for updating the threshold value. For example, the setting information of step 501 may not include a threshold value for identifying whether interference (e.g., instantaneous interference) associated with the second base station has occurred. In this case, the first base station (160) may transmit information regarding the threshold value for identifying whether interference has occurred within the DCI, and the FWA device (120) may identify whether instantaneous interference has occurred based on the threshold value of the DCI, the average SINR value, the current SINR value, and / or the minimum SINR value.

[0166] For example, the configuration information of step 501 may include a first threshold value for identifying whether interference (e.g., instantaneous interference) associated with the second base station has occurred. If a second threshold value of N bits within the DCI of step 802 is newly transmitted to the FWA device (120), the first threshold value may be updated to the second threshold value. In this case, the FWA device (120) may identify whether instantaneous interference has occurred based on the second threshold value of the DCI, the average SINR value, the current SINR value, and / or the minimum SINR value.

[0167] Steps 501 to 518 of FIG. 8 of the present disclosure may correspond to steps 501 to 518 of FIG. 5. For example, the first base station (160) may transmit configuration information to the FWA device (120) via RRC signaling in step 501. For example, the first base station (160) may transmit a first PDSCH (physical downlink shared channel) to the FWA device (120) in step 503. For example, the FWA device (120) may transmit a first UCI (uplink control information) containing HARQ information for the PDSCH in step 505. For example, the first base station (160) may transmit a second PDSCH in step 507. For example, the FWA device (120) may transmit a second UCI to the first base station (160) at step 509, which includes HARQ information for the second PDSCH and / or an indicator indicating whether there is interference (e.g., instantaneous interference) associated with the second base station. The first base station (160) may lower the MCS from 11 to 10 for data transmission at step 510. The first base station (160) may transmit a third PDSCH to the FWA device (120) at step 511. The FWA device (120) may transmit a third UCI to the first base station (160) at step 513, which includes a NACK and / or an indicator (e.g., an IIF indicator) indicating a failure to receive the third PDSCH. The first base station (160) may determine the MCS level based on the received NACK and indicator (e.g., an IIF indicator) at step 514. The first base station (160) may transmit a fourth PDSCH to the FWA device (120) in step 515. If the FWA device (120) succeeds in receiving the fourth PDSCH in step 517, it may transmit a fourth UCI including an ACK to the first base station (160), and the first base station (160) may raise the MCS level based on the ACK information in step 518.

[0168] In FIG. 8 of the present disclosure, the FWA device (120) is described as performing the collection and reporting of information for reporting based on RRC messages and DCI, but this is merely an example. For example, the FWA device (120) may perform the collection of information for reporting and UCI reporting including indicators based on RRC messages, MAC CE, and DCI. For example, the FWA device (120) may be configured to perform UCI reporting through RRC messages. The FWA device (120) may be triggered to perform UCI reporting including IIF indicators through MAC CE and / or DCI.

[0169] FIG. 9 is a diagram illustrating a method for retransmitting PDSCH according to one embodiment.

[0170] Referring to FIG. 9, a first base station (160) according to one embodiment may transmit configuration information for reporting for interference management to an FWA device (120) in step 501. For example, the configuration information may include an indicator indicating whether to perform a report (or UCI report) for the management of interference (e.g., instantaneous interference) associated with the second base station. For example, the configuration information may include information on a threshold value (e.g., SINR gap) for identifying interference (e.g., instantaneous interference) associated with the second base station. For example, the configuration information may include a HARQ flush indicator indicating whether the FWA device (120) should save the original TB (transport block) in the event of a failure to receive the PDSCH. For example, the configuration information may include information for a redundancy version (RV) (e.g., repK-RV-IIF) that may include all codewords corresponding to the PDSCH when the PDSCH is retransmitted.

[0171] [Table 4] is an example of configuration information for reporting for interference management.

[0172]

[0173] The indicator in [Table 4] may be an indicator indicating whether to perform reporting for interference management. The Threshold may be a threshold value for identifying instantaneous interference. The HarqFlushindicator may be an indicator indicating whether to save the original TB in the event of a PDSCH reception failure or decoding failure. In other words, it may be an indicator of whether to empty the data rather than save it to the HARQ buffer in the event of a transmission failure caused by instantaneous interference. Additionally, since retransmitted data must contain all of the original data, the repK-RV-IIF may be information for setting a different order of the RV (redundancy version) in the event of instantaneous interference.

[0174] According to one embodiment, the FWA device (120) is instructed to perform a report for interference management based on received configuration information, and can collect and / or manage information (e.g., average SINR, real-time SINR) to determine whether there is instantaneous interference when the HARQ flush indicator is set to true.

[0175] According to one embodiment, the HARQ flush indicator may be determined based on an indicator that indicates whether to perform a report for interference management. For example, if the indicator indicating whether to perform a report within the configuration information of step 501 is set to 1 (or true), the HARQ flush indicator may also be set to 1 (or true). In this case, the FWA device (120) may identify whether interference (e.g., instantaneous interference) associated with the second base station has occurred, and if interference has occurred, it may flush the data corresponding to the failed-received PDSCH without storing it in the buffer. For example, if the indicator indicating whether to perform a report within the configuration information of step 501 is set to 0 (or false), the HARQ flush indicator may also be set to 0 (or false). In this case, the FWA device (120) may not determine whether interference (e.g., instantaneous interference) associated with the second base station has occurred, and may store the data corresponding to the failed-received PDSCH in the buffer.

[0176] However, the relationship between the indicator indicating whether to perform a report and the HARQ flush indicator is merely an example and can be set independently as needed. For example, if the indicator indicating whether to perform a report is 1 (or true), the HARQ flush indicator may be 0 (or false). In this case, the FWA device (120) can store the original TB in the buffer even if it fails to receive the PDSCH due to instantaneous interference.

[0177] According to one embodiment, the first base station (160) may transmit a first physical downlink shared channel (PDSCH) to the FWA device (120) in step 503. For example, the first base station (160) may transmit downlink control information (DCI) scheduling the first PDSCH to the FWA device (120) on a physical downlink control channel (PDCCH). The first base station (160) may transmit data on the PDSCH to the FWA device (120) based on the DCI.

[0178] According to one embodiment, the FWA device (120) may transmit a first UCI (uplink control information) containing HARQ information for the PDSCH in step 505. For example, if the FWA device (120) succeeds in receiving the PDSCH, it may transmit a first UCI containing an ACK (acknowledge) indicating to the first base station (160) that the PDSCH has been successfully received.

[0179] According to one embodiment, the first base station (160) can transmit the third PDSCH to the FWA device (120) in step 511.

[0180] According to one embodiment, the FWA device (120) can identify a failure in receiving the third PDSCH. The FWA device (120) can transmit a third UCI containing a NACK and / or an indicator (e.g., an IIF indicator) indicating a failure in receiving the third PDSCH to the first base station (160) in step 513. In this case, the FWA device (120) can identify that the failure in receiving the third PDSCH is based on interference (e.g., instantaneous interference) associated with the second base station based on a SINR value and a threshold value before transmitting the indicator. Accordingly, the FWA device (120) can transmit to the first base station (160) the value of the indicator (e.g., an IIF indicator) transmitted along with the NACK to be set to 1 (or true).

[0181] According to one embodiment, the first base station (160) may retransmit the third PDSCH to the FWA device (120) in step 915. When the first base station (160) performs the retransmission of the third PDSCH, the first base station (160) may toggle the new data indicator (NDI) or may not toggle the NDI.

[0182] For example, the first base station (160) may perform retransmission for the TB corresponding to the PDSCH that received the NACK, in which case it may toggle the NDI and select an RV (e.g., 2) among the RVs (e.g., 0, 1, 2) that can contain all of the original codeword. The FWA device (120) may identify the RV selected by the first base station (160) based on information about the RV (e.g., repK-RV-IIF) in the configuration information of step 510. For example, the first base station (160) may not toggle the NDI, but may set the RV to 0 based on substantially the same HARQ processor ID (identifier) ​​and perform retransmission of the third PDSCH.

[0183] In FIG. 9 of the present disclosure, information about the RV (e.g., repK-RV-IIF) is described as being included in the configuration information through RRC signaling, but this is merely an example. For example, information about the RV (e.g., repK-RV-IIF) may be included in the DCI.

[0184] FIG. 10a illustrates a method for performing a handover for interference management according to one embodiment.

[0185] Referring to FIG. 10a, a wireless communication system according to one embodiment may include an FWA device (120), a source base station (1021), a target base station (1022), an access and mobility management function (AMF) entity (1023), and / or a user plane function (UPF) entity (1024). For example, the source base station (1021) may correspond to the first base station (160) of FIGS. 1 to 9, and the target base station (1022) may correspond to the second base station of FIGS. 1 to 9.

[0186] Hereinafter, in FIG. 10a, a method is described in which a first base station (160) corresponding to a source base station (1021) recognizes the occurrence of instantaneous interference and identifies the transmission beam of a second base station that causes instantaneous interference in order to avoid further occurrence of instantaneous interference. In order to identify the transmission beam of a second base station that causes instantaneous interference, an FWA device (120) needs to hand over to the second base station. For example, when the second base station operates a non-periodic CSI (channel state information)-RS (reference signal), it is not known at what time the second base station will transmit the CSI-RS, and accordingly, without a handover of the FWA device (120), the transmission beam of the second base station that causes instantaneous interference cannot be identified. Accordingly, in order to eliminate interference associated with the second base station (e.g., instantaneous interference), a handover of the FWA device (120) to the second base station (e.g., target base station (1022)) may be required, and the handover of the FWA device (120) for interference elimination is described below.

[0187] According to one embodiment, in step 1010, the access and mobility management function (AMF) entity (1023) may provide mobility control information to the source base station (1021) and / or the target base station (1022).

[0188] According to one embodiment, in step 1011, the FWA device (120) can perform measurement control and reporting to the source base station (1021). For example, the source base station (1021) can set up a measurement procedure for the FWA device (120), and the FWA device (120) can transmit measurements to the source base station (1021) based on the set measurement information.

[0189] For example, the FWA device (120) can receive data on the PDSCH from the source base station (1021) and transmit UCI information corresponding to the data to the source base station (1021). That is, if the reception of the PDSCH from the source base station (1021) fails, the FWA device (120) can transmit a UCI to the source base station (1021) that includes a NACK indicating that the reception of the PDSCH failed and an indicator indicating whether the reception failure is based on interference associated with the target base station (1022).

[0190] The UCI transmitted by the FWA device (120) to the source base station (1021) may include an indicator (e.g., “1”, or true) indicating that the failure of reception is based on interference associated with the target base station (1022) (e.g., the second base station).

[0191] According to one embodiment, if the source base station (1021) includes an indicator indicating that the reception failure is based on interference associated with the target base station (1022), the source base station (1021) may determine a handover for interference management in step 1012. For example, the source base station (1021) may determine a handover for interference management based on a UCI received from the FWA device (120). For example, the source base station (1021) may determine a handover for interference management when an indicator indicating that instantaneous interference has occurred is received from the FWA device (120) more than a specified number of times. For example, the source base station (1021) may determine a handover for interference management when indicators indicating that instantaneous interference has occurred from the FWA device (120) are repeatedly received within a specified interval. In this case, the target base station (1022) may instruct the FWA device (120) to perform a handover for interference management.

[0192] According to one embodiment, the handover for interference management may be a handover for removing interference associated with the target base station (1022). For example, when interference associated with the target base station (1022) occurs, the FWA device (120) and / or the source base station (1021) need to remove the interference (e.g., instantaneous interference). To remove the interference, the transmission beam of the target base station (1022) may be changed or the reception beam of the FWA device (120) may be changed. To change the transmission beam of the target base station (1022), the FWA device (120) may directly hand over to the target base station (1022) and identify the transmission beam of the target base station (1022) that is causing the interference. Accordingly, the handover for interference management (e.g., semi-handover, handover with some procedures omitted, handover for interference control, transient handover, temporary handover, handover for beam management) may correspond to a handover for removing instantaneous interference, unlike a general handover.

[0193] For example, a semi-handover may be referred to as a handover in which the FWA device (120) undergoes a handover process to the target base station (1022), but the source base station (1021) and the target base station (1022) are not performing the handover due to causes associated with the FWA device (120), such as signal quality degradation, but rather a handover performed temporarily to measure the source of interference.

[0194] In this disclosure, the term "semi-handover" (or "handover for interference management") is not limited to the term itself and may be replaced by various terms designated by the definitions set forth above. That is, the term "semi-handover" may be replaced by other terms that are consistent with the definition and context.

[0195] According to one embodiment, a handover for interference management (e.g., semi-handover, handover in which some procedures are omitted, handover for interference control, temporary handover, temporary handover, handover for beam management) may be predicated on the return (or re-handover) of the FWA device (120) to the source base station (1021), unlike a general handover. For example, in the case of a general handover, it may be advantageous for communication to connect to the target base station (1022) as a result of measurement, and accordingly, it may not be predicated on the return (or re-handover) of the FWA device (120) to the source base station (1021) after the handover. On the other hand, a handover for interference management (e.g., semi-handover) may be predicated on the FWA device (120) being reconnected to the source base station (1021) after the FWA device (120) has connected to the target base station (1022) and identified the transmission beam that induces interference.

[0196] For example, a handover for interference management (e.g., semi-handover) may not be a general handover performed as signal quality deteriorates, but rather a temporary procedure to identify the source of interference (e.g., a beam of the target base station (1022)) causing instantaneous interference. For example, unlike a general handover, in a handover for interference management (e.g., semi-handover), the data path of the FWA device (120) may not be changed, and path changes between base stations and upper-layer signal transmission and reception procedures may be omitted.

[0197] According to one embodiment, the source base station (1021) may transmit a handover request to the target base station (1022) in step 1013 based on the handover determined for interference management. For example, the handover request may include a target cell ID, a KgNB, and / or a cell-radio network temporary identifier (C-RNTI) assigned to the FWA device (120) of the source base station (1021).

[0198] According to one embodiment, the target base station (1022) can perform admission control based on the handover request being performed in step 1014.

[0199] According to one embodiment, the target base station (1022) may transmit a handover request ACK to the source base station (1021) in step 1015. For example, the target base station (1022) may transmit a message to the source base station (1021) indicating that the handover request has been accepted.

[0200] According to one embodiment, the source base station (1021) may transmit a message instructing the FWA device (120) in step 1016 to perform a handover (e.g., a semi-handover) for interference management. In this case, a handover for interference management to the target base station (1022) of the FWA device (120) may be initiated.

[0201] According to one embodiment, the FWA device (120) may perform a random access procedure with the target base station (1022) based on receiving a message directing a handover. For example, the FWA device (120) may transmit a random access preamble to the target base station (1022). The target base station (1022) may transmit a random access response to the FWA device (120) in response to the random access preamble.

[0202] According to one embodiment, a handover for interference management can be completed in step 1017 based on the completion of the random access procedure between the FWA device (120) and the target base station (1022).

[0203] According to one embodiment, the random access preamble transmitted to the target base station (1022) during the handover for interference management may be configured separately. For example, the random access preamble transmitted in step 1017 may be a random access preamble dedicated to the handover for interference management.

[0204] [Table 5] is an example of configuration information (e.g., RACH-configCommon) associated with a random access preamble that is set to the FWA device (120) via RRC signaling for interference management handover.

[0205]

[0206] The FWA device (120) can receive a preamble set (e.g., restrictedSetTypeC) included in the configuration information (e.g., RACH-configCommon) of [Table 5]. The preamble set (e.g., restrictedSetTypeC) can be dedicated to a handover for interference management.

[0207] As another example, the random access preamble transmitted in step 1017 may be a random access preamble agreed upon in advance by the source base station (1021) and the target base station (1022).

[0208] According to one embodiment, the FWA device (120) can identify the transmission beam with the highest RSRP value among the transmission beams of the target base station (1022) after performing synchronization with the target base station (1022) through a random access procedure. The identified transmission beam can be utilized for interference cancellation as described in FIG. 11.

[0209] According to one embodiment, the FWA device (120) can identify the transmission beam with the highest RSRP value among the transmission beams of the source base station (1021) and the reception beam of the FWA device (120). For example, the FWA device (120) can identify the optimal transmission beam of the source base station (1021) and the optimal reception beam corresponding to the optimal transmission beam (e.g., the transmission beam with the highest RSRP) for interference management during or prior to performing a random access procedure.

[0210] In FIGS. 10a to 11 below, a method for eliminating interference (e.g., instantaneous interference) associated with a target base station (1022) using a transmitting beam with the highest RSRP value and a receiving beam corresponding to the highest transmitting beam is described.

[0211] In FIG. 10a of the present disclosure, it is described that a source base station (1021) transmits a handover request to a target base station (1022) to trigger a handover for interference management, but this is merely an example. For example, the name of the message requesting the target base station (1022) from the source base station (1021) may vary.

[0212] FIG. 10b illustrates a general handover according to one embodiment.

[0213] Referring to Fig. 10b, a general handover is described that is distinct from the handover for interference management of Fig. 10a.

[0214] According to one embodiment, in step 1010, the access and mobility management function (AMF) entity (1023) may provide mobility control information to the source base station (1021) and / or the target base station (1022).

[0215] According to one embodiment, in step 1011, the FWA device (120) can perform measurement control and reporting to the source base station (1021).

[0216] According to one embodiment, if the failure of reception includes an indicator that indicates that the failure is based on interference associated with the target base station (1022), the source base station (1021) may determine a handover for interference management in step 1012.

[0217] According to one embodiment, the source base station (1021) may transmit a handover request to the target base station (1022) in step 1013 based on the handover determined for interference management.

[0218] According to one embodiment, the target base station (1022) can transmit a handover request ACK to the source base station (1021) in step 1015.

[0219] According to one embodiment, the source base station (1021) may transmit a message to the FWA device (120) in step 1016 instructing a handover (e.g., semi-handover) for interference management.

[0220] According to one embodiment, a handover for interference management can be completed in step 1017 based on the completion of the random access procedure between the FWA device (120) and the target base station (1022).

[0221] According to one embodiment, the source base station (1021) may transmit an early status transfer message to the target base station (1022) in step 1020, and the source base station (1021) may transmit an SN status to the target base station (1022) in step 1021. The target base station (1022) may buffer user data from the source base station (1021) in step 1022.

[0222] According to one embodiment, the target base station (1022) may transmit a handover success to the source base station (1021) in step 1023a. The source base station (1021) may transmit an SN status to the target base station (1022) in step 1023b. The target base station (1022) may request a path switch from the UPF (1024) in step 1024.

[0223] According to one embodiment, the AMF (1023) and the UPF (1024) can switch paths in step 1024. The target base station (1022) can send an ACK of the path switch request to the UPF (1024). The target base station (1022) can send a UE context release to the source base station (1021).

[0224] In the handover for interference management of the present disclosure (e.g., semi-handover), steps 1011 through 1017 may be performed as described in FIG. 10a. On the other hand, in a general handover, steps 1011 through 1027 may all be performed. Consequently, in a handover for interference management, some steps may be omitted compared to a general handover.

[0225] FIG. 11 illustrates a method for eliminating interference by stopping the use of a transmission beam of a second base station that causes interference according to one embodiment.

[0226] Referring to FIG. 11, an FWA device (120) according to one embodiment can identify the optimal beam of the target base station (1022) after handing over to the target base station (1022). For example, the FWA device (120) can identify the transmission beam with the largest RSRP value among the transmission beams of the target base station (1022) as the optimal beam.

[0227] According to one embodiment, the FWA device (120) can identify a first transmission beam of a source base station (1021) having a maximum RSRP value and a second transmission beam of a target base station (1022) having a maximum RSRP value. For example, while connected to the target base station (1022) via handover, the FWA device (120) can identify and store the second transmission beam having the highest RSRP value (e.g., CRI-RSRP) among the transmission beams of the target base station (1022). In this case, the FWA device (120) can identify a threshold value set to eliminate interference.

[0228] According to one embodiment, when the FWA device (120) searches for a second transmission beam of a target base station (1022), the optimal reception beam with the source base station (1021) can be fixed. That is, the FWA device (120) can search for the second transmission beam with the highest RSRP value among the transmission beams of the target base station (1022) while keeping the reception beam of the FWA device (120) corresponding to the first transmission beam with the highest RSRP fixed.

[0229] In the present disclosure, the FWA device (120) can identify a second transmission beam using the SSB (synchronization signal block) RI (resource index) and / or CRI-RSRP.

[0230] According to one embodiment, the FWA device (120) can determine in step 1101 whether the difference between the maximum RSRP value corresponding to the first transmission beam and the maximum RSRP value corresponding to the second transmission beam is less than a threshold value. For example, the threshold value for removing interference may be set to the FWA device (120) based on RRC signaling, MAC CE and / or DCI. For example, the threshold value for removing interference may be substantially the same as the threshold value included in the setting information of step 501 of FIG. 5. For example, the threshold value for removing interference may be different from the threshold value included in the setting information of step 501 of FIG. 5.

[0231] If the difference between the maximum RSRP values ​​is smaller than the threshold value, it may practically mean that the second transmission beam is an interference source for the first transmission beam. For example, a difference between the maximum RSRP values ​​being smaller than the threshold value may mean that there is a high correlation between the first transmission beam and the second transmission beam, and that they may cause mutual interference.

[0232] According to one embodiment, the FWA device (120) may hand over to another target base station in step 1103 if the difference between the maximum RSRP value of the source base station (1021) and the maximum RSRP value of the target base station (1022) is greater than or equal to a threshold value. For example, the difference between the maximum RSRP values ​​being greater than or equal to a threshold value may mean that the correlation between the first transmission beam of the source base station (1021) and the second transmission beam of the target base station (1022) is low, and the likelihood of mutual interference is low. Accordingly, the FWA device (120) may hand over to another target base station to identify the source of instantaneous interference (e.g., the optimal transmission beam of another base station).

[0233] The FWA device (120) that has handed over to another target base station may repeat steps 1101, 1105, and 1107 to search for an interference source (e.g., the optimal transmission beam of another base station).

[0234] According to one embodiment, the FWA device (120) may transmit a CRI (CSI-RS resource indicator) RSRP to the target base station (1022) in step 1105 if the difference between the maximum RSRP value of the source base station (1021) and the maximum RSRP value of the target base station (1022) is less than a threshold value. For example, a difference between the maximum RSRP values ​​being less than a threshold value may mean that the first transmission beam and the second transmission beam have a high correlation and that the second transmission beam acts as an interference source for the first transmission beam. In this case, the FWA device (120) may transmit a CRI RSRP corresponding to the second transmission beam to the target base station (1022) to eliminate interference. According to one embodiment, the FWA device (120) may hand over (e.g., return) to the source base station (1021) in step 1107.

[0235] According to one embodiment, a target base station (1022) that receives a CRI RSRP may decide whether to stop using the second transmission beam to eliminate interference. For example, the target base station (1022) may receive a CRI RSRP corresponding to the second transmission beam from an FWA device (120) and may decide whether to stop using the second transmission beam.

[0236] For example, if the target base station (1022) can stop using the second transmission beam to eliminate interference, it may send a message (e.g., confirmation message, allow message) to the source base station (1021) and / or FWA device (120) indicating that the use of the second transmission beam is stopped. For example, if the target base station (1022) cannot stop using the second transmission beam, it may send a message (e.g., reject message) to the source base station (1021) and / or FWA device (120) indicating that the use of the second transmission beam cannot be stopped.

[0237] FIG. 12 illustrates a method for determining whether a target base station can change a transmission beam according to one embodiment.

[0238] Referring to FIG. 12, an FWA device (120) according to one embodiment may report a maximum CRI RSRP to a target base station (1022). For example, the procedure for reporting the maximum CRI RSRP of the FWA device (120) may substantially refer to a procedure for requesting the target base station (1022) to replace the second transmission beam corresponding to the maximum CRI RSRP with another beam to eliminate interference. For example, the procedure for reporting the maximum CRI RSRP of the FWA device (120) may substantially refer to a procedure for requesting the target base station (1022) to stop using the second transmission beam corresponding to the maximum CRI RSRP to eliminate interference.

[0239] According to one embodiment, the target base station (1022) may determine in step 1203 whether the second transmission beam corresponding to the maximum CRI RSRP can be changed to the third transmission beam. For example, the target base station (1022) may determine that the second transmission beam can be replaced with the third transmission beam if there is no data being transmitted through the second transmission beam or if it can be replaced with another beam. For example, the target base station (1022) may determine that the second transmission beam cannot be replaced and the use of the second transmission beam cannot be stopped if there is data being transmitted through the second transmission beam or if there is no other replaceable beam. For example, the target base station (1022) may determine whether to stop the use of the second transmission beam based on the quality of service (QoS) corresponding to the data being transmitted through the second transmission beam. The target base station (1022) may determine that the use of the second transmission beam cannot be stopped if the QoS corresponding to the data is greater than or equal to the threshold QoS. The target base station (1022) may determine that it can stop using the second transmission beam if the QoS corresponding to the data is less than the threshold QoS.

[0240] According to one embodiment, the target base station (1022) may transmit a response message to the FWA device (120) in step 1205. For example, if the use of the second transmission beam can be stopped, the target base station (1022) may transmit a message to the FWA device (120) indicating that the use of the second transmission beam has been stopped. For example, if the use of the second transmission beam cannot be stopped, the target base station (1022) may transmit a message to the FWA device (120) indicating that the use of the second transmission beam cannot be stopped.

[0241] According to one embodiment, the FWA device (120) can hand over to the source base station (1021) in step 1207. For example, the FWA device (120) can hand over to the source base station (1021) regardless of whether the use of the second transmission beam can be stopped. For example, if the FWA device (120) receives a message (e.g., confirmation message, permission message) from the target base station (1022) indicating that the use of the second transmission beam has been stopped, the FWA device (120) can hand over to the source base station (1021) again and perform communication using the first transmission beam and the receiving beam corresponding to the first transmission beam. In this case, instantaneous interference caused by the second transmission beam can be eliminated because the use of the second transmission beam has been stopped. For example, if the FWA device (120) receives a message (e.g., a reject message) from the target base station (1022) indicating that the use of the second transmission beam has not been stopped, the FWA device (120) can re-handover to the source base station (1021) and identify whether the reception beam can be changed.

[0242] According to one embodiment, the FWA device (120) that has handed over to the source base station (1021) can transmit the result of the handover (e.g., whether to stop using the second transmission beam (or whether to remove the interference source)) to the source base station (1021).

[0243] Figure 13 below describes a method in which an FWA device (120) changes the receiving beam to eliminate interference.

[0244] Step 1201 of Fig. 12 may correspond to Step 1105 of Fig. 11, and unless there is a contradiction, the description of Step 1105 may be applied to Step 1201.

[0245] FIG. 13 illustrates a method for changing the receiving beam of an FWA device according to one embodiment.

[0246] Referring to FIG. 13, an FWA device (120) according to one embodiment can identify a receiving beam in step 1301 in which the difference between the RSRP value for the source base station (1021) and the RSRP value for the target base station (1022) is greater than a threshold value. For example, the FWA device (120) may use (or form) a plurality of receiving beams (e.g., N receiving beams) to perform communication with the source base station (1021) and the target base station (1022). For example, the FWA device (120) may use N receiving beams, and a beam index may be assigned to each of the N receiving beams.

[0247] The FWA device (120) can identify and store RSRP values ​​for the source base station (1021) and the target base station (1022) when using each of the N receiving beams. For example, the FWA device (120) can identify RSRP values ​​for the N receiving beams while RRC connected to the source base station (1021) and can store the identified RSRP values. For example, the FWA device (120) can identify RSRP values ​​for the N receiving beams while RRC connected to the target base station (1022) after performing a handover to the target base station (1022) and can store the identified RSRP values. Consequently, the FWA device (120) can identify RSRP values ​​for the source base station (1021) and RSRP values ​​for the target base station (1022) for each of the N receiving beams.

[0248] The FWA device (120) can determine whether the difference between the RSRP value for the source base station (1021) and the RSRP value for the target base station (1022) is greater than a threshold value for each receiving beam assigned a beam index. For example, for a first receiving beam assigned a beam index i, the FWA device (120) can determine whether the difference between the RSRP value for the source base station (1021) and the RSRP value for the target base station (1022) is greater than a threshold value. For example, for a second receiving beam assigned a beam index i+1, the FWA device (120) can determine whether the difference between the RSRP value for the source base station (1021) and the RSRP value for the target base station (1022) is greater than a threshold value. Likewise, for each of N receiving beams (e.g., multiple receiving beams), the FWA device (120) can determine whether the difference between the RSRP values ​​is greater than a threshold value.

[0249] The FWA device (120) can identify a first receiving beam among N beams in which the difference between the RSRP value for the source base station (1021) and the RSRP value for the target base station (1022) is greater than a threshold value. For example, the first receiving beam may correspond to beam index i. For example, the first receiving beam may be a receiving beam associated with interference associated with the target base station (1022). That is, a large difference between the RSRP values ​​for the source base station (1021) and the target base station (1022), respectively, may substantially imply a low probability of interference, and consequently, may imply that the first receiving beam is a receiving beam for interference cancellation.

[0250] According to one embodiment, among a plurality of receiving beams, there may be multiple receiving beams in which the difference between the RSRP value for the source base station (1021) and the RSRP value for the target base station (1022) is greater than a threshold value. In this case, the FWA device (120) can identify the beam with the largest difference in RSRP values ​​among the receiving beams as the receiving beam for interference cancellation.

[0251] According to one embodiment, information regarding beam indices corresponding to a plurality of received beams (e.g., N received beams) may be assigned to an FWA device (120) from a source base station (1021) and / or a target base station (1022). For example, the source base station (1021) may transmit information regarding beam indices to the FWA device (120) via RRC signaling and may transmit information regarding beam indices to the target base station (1022) during a handover for interference management.

[0252] For example, the threshold value for removing interference may be substantially the same as the threshold value included in the setting information of step 501 of FIG. 5. For example, the threshold value for removing interference may be different from the threshold value included in the setting information of step 501 of FIG. 5. For example, the threshold value for removing interference may be set separately for the FWA device (120) via RRC settings, MAC CE, and / or DCI.

[0253] According to one embodiment, the FWA device (120) can perform a handover to the source base station (1021) in step 1303. For example, the FWA device (120) can identify the RSRP values ​​that a plurality of receiving beams have for the target base station (1022) by performing a handover to the target base station (1022), and can identify a first receiving beam (e.g., a receiving beam for interference cancellation) based on the RSRP values. Since the identification of the first receiving beam is complete, the FWA device (120) can perform a handover to the source base station (1021) again.

[0254] According to one embodiment, prior to step 1303, the FWA device (120) may receive a response message from the target base station (1022) in step 1205 indicating whether to stop using the second transmission beam associated with interference. For example, if the FWA device (120) receives a message (e.g., a reject message) from the target base station (1022) indicating that stopping the use of the second transmission beam is not possible, it may identify the first reception beam where the difference between the RSRP values ​​is greater than a threshold value for interference management.

[0255] However, this is merely an example and the present disclosure is not limited thereto. For example, in FIG. 13 of the present disclosure, it is described that step 1301 is performed after step 1205, but this is merely an example. For example, the FWA device (120) may perform the operation of identifying a first receiving beam in which the difference between RSRP values ​​is greater than a threshold value regardless of the reception of a response message. For example, the FWA device (120) may perform step 1301 before performing step 1205. For example, the FWA device (120) may perform step 1301 even if it receives a message (e.g., a confirm message) from the target base station (1022) indicating that the use of the second transmitting beam has been stopped.

[0256] According to one embodiment, the FWA device (120) may transmit a non-periodic CSI request to the source base station (1021) in step 1305. For example, the FWA device (120) may identify a first receiving beam as a receiving beam to eliminate interference associated with the target base station (1022). In this case, the transmitting beam of the source base station (1021) corresponding to the first receiving beam may have changed when the FWA device (120) handovers to the source base station (1021). For example, before the FWA device (120) handovers to the target base station (1022), the transmitting beam having the maximum RSRP value for the first receiving beam may be the first transmitting beam. In this case, after the FWA device (120) handovers again from the target base station (1022) to the source base station (1021), the transmitting beam having the maximum RSRP value for the first receiving beam may be the second transmitting beam. That is, after handover to the source base station (1021), the FWA device (120) can transmit a non-periodic CSI request to the source base station (1021) to identify whether the transmission beam corresponding to the first receiving beam has changed, and if so, which transmission beam it is.

[0257] According to one embodiment, the FWA device (120) can receive CSI for beam management (BM) in step 1307. For example, the source base station (1021) can allocate CSI resources to the FWA device (120) in response to receiving the CSI request and identify a transmission beam corresponding to the first received beam.

[0258] FIG. 14 illustrates a method for eliminating interference associated with a second base station through cooperative scheduling between base stations according to one embodiment.

[0259] Referring to FIG. 14, a wireless communication system according to one embodiment (e.g., the wireless access network (140) of FIG. 1) may include a first base station (160) and a second base station (1412). For example, the first base station (160) may correspond to the source base station (1021) of FIG. 10a. For example, the second base station (1412) may correspond to the second base station of FIG. 1 through FIG. 13 and may correspond to the target base station (1022) of FIG. 10a. For example, the second base station (1412) may correspond to a base station that causes interference (e.g., instantaneous interference) in communication between the first base station (160) and the FWA device (120).

[0260] According to one embodiment, in step 1401, the first base station (160) may transmit a request for information regarding a scheduled beam to the second base station (1412). For example, the first base station (160) may need to identify information regarding the transmission beam of the second base station (1412) in order to reduce or minimize interference (e.g., instantaneous interference) associated with the second base station (1412). For example, interference (e.g., instantaneous interference) associated with the second base station (1412) may occur as the second transmission beam used by the second base station (1412) for communication overlaps with or interferes with the first transmission beam of the first base station (160). Therefore, the first base station (160) may need to identify information regarding the second transmission beam of the second base station (1412) that is the source of interference in order to reduce interference (e.g., instantaneous interference) associated with the second base station (1412). Consequently, the first base station (160) can send a request for information about the scheduled beam to the second base station (1412) to identify the source of interference (e.g., the second transmission beam).

[0261] According to one embodiment, a request for information regarding a scheduled beam may include a request for information regarding a beam index used by the second base station (1412) in a slot where the FWA device (120) transmitted an indicator (e.g., an IIF indicator). For example, the first base station (160) may receive a UCI from the FWA device (120) within a designated slot that includes an indicator (e.g., an IIF indicator) indicating that interference is based on interference associated with the second base station (1412). In this case, the first base station (160) may request information (e.g., beam index i) from the second base station (1412) regarding a beam index corresponding to the second transmitted beam used in the designated slot based on the indicator.

[0262] According to one embodiment, the first base station (160) may receive information about a scheduled beam from the second base station (1412) in step 1403. For example, the second base station (1412) may receive a request for information about a scheduled beam from the first base station (160) and transmit information about a scheduled beam to the first base station (160) based on the information request. For example, the information about the scheduled beam may include information about a beam index for a second transmission beam and / or information indicating the angle of the second transmission beam (e.g., a precoding matrix indication (PMI)).

[0263] According to one embodiment, the first base station (160) may transmit a request to the second base station (1412) for interference reduction. For example, the first base station (160) may receive information about a scheduled beam from the second base station (1412) and, based on the information about the beam, identify that the transmission beam causing interference is the second transmission beam. In this case, the first base station (160) may transmit a request to the second base station (1412) instructing it to stop using the second transmission beam.

[0264] For example, the first base station (160) may request the second base station (1412) not to use the second transmission beam in a specific time domain. For example, the first base station (160) may request the second base station (1412) not to use it during a specified slot, symbol, subframe, and / or frame.

[0265] For example, the first base station (160) may request the second base station (1412) not to use the second transmission beam in a specific frequency domain. For example, the first base station (160) may request the second base station (1412) not to use it during a specified frequency band, a specified subband, a specified cell, and / or a specified carrier.

[0266] According to one embodiment, the first base station (160) may receive an ACK for a request for interference reduction from the second base station (1412). For example, the second base station (1412) may decide whether to accept the request in response to receiving the request for interference reduction from the first base station (160). For example, if the second base station (1412) accepts the request, it may stop using the second transmission beam during a specified time domain and / or a specified frequency domain and send a confirm message to the first base station (160). For example, if the second base station (1412) rejects the request, it may continue using the second transmission beam and send a reject message to the first base station (160).

[0267] [Table 6] is an example of a message for information exchange between the first base station (160) and the second base station (1412).

[0268]

[0269] According to one embodiment, when interference (e.g., instantaneous interference) is eliminated through the exchange of scheduling information between the first base station (160) and the second base station (1412), the interference can be eliminated without the need for the FWA device (120) to perform a handover for interference management. Therefore, when interference is eliminated through the exchange of scheduling information between the first base station (160) and the second base station (1412), the interference can be eliminated without interruption of data reception by the FWA device (120). For example, when the FWA device (120) performs a handover for interference management, the FWA device (120) may stop receiving data (e.g., PDSCHs) from the first base station (160). On the other hand, when interference is eliminated through the exchange of scheduling information between the first base station (160) and the second base station (1412), the interference can be eliminated while the FWA device (120) continuously receives data (e.g., PDSCHs).

[0270] According to one embodiment, a fixed wireless access (FWA) device in a wireless communication system includes a transceiver and a controller coupled to the transceiver, and the controller may be configured to receive configuration information regarding interference management associated with a second base station from a first base station, and, if reception of a physical downlink shared channel (PDSCH) from the first base station fails, identify whether the failure of reception of the PDSCH is based on interference associated with the second base station based on the configuration information, and transmit uplink control information (UCI) to the first base station, the UCI including information indicating whether the failure of reception of the PDSCH is based on the interference.

[0271] According to one embodiment, the setting information includes information regarding a threshold value for interference management, and the controller may be configured to identify an average SINR (signal to interference plus noise ratio) value over a specified period and a SINR value at the point in time when the reception of the PDSCH is identified as having failed, and to identify that the failure of the reception of the PDSCH is based on interference when the difference between the average SINR value and the SINR value exceeds the threshold value.

[0272] According to one embodiment, the setting information includes an indicator for indicating whether to report the UCI, and the controller receives a MAC (medium access control) CE (control element) from the first base station that enables the reporting of the UCI, and may be configured to identify information for interference management associated with the second base station based on the indicator and the MAC CE.

[0273] According to one embodiment, the configuration information includes an indicator for indicating whether to report the UCI, and the controller receives downlink control information (DCI) for scheduling the PDSCH, and if the indicator of the configuration information indicates reporting the UCI and the DCI includes a field that triggers reporting the UCI, the information for interference management associated with the second base station may be configured to identify information for interference management.

[0274] According to one embodiment, if the failure of the reception of the PDSCH is based on the interference, the modulation and coding scheme (MCS) level for communication between the first base station and the FWA device is maintained, and if the failure of the reception of the PDSCH is not based on the interference, the MCS level may be adjusted (e.g., lowered).

[0275] According to one embodiment, the UCI includes a negative acknowledgment (NACK) for the PDSCH and information indicating whether the failure of reception of the PDSCH is based on the interference, and if the information indicates that the failure is based on the interference, the transport block (TB) for the PDSCH is flushed, and if the information indicates that the failure is not based on the interference, the TB for the PDSCH can be stored in a buffer of the FWA device.

[0276] According to one embodiment, if the failure of the reception of the PDSCH is based on the interference, the controller transmits a random access preamble for a handover for interference management to the second base station, receives a random access response from the second base station, determines whether the difference between the RSRP (reference signals received power) value of the first transmission beam of the first base station and the RSRP value of the second transmission beam of the second base station is smaller than a threshold value, and if the difference is smaller than the threshold value, is configured to transmit information associated with the second transmission beam to the second base station, and the random access preamble may be configured for interference management.

[0277] According to one embodiment, based on the information associated with the second transmission beam, the transmission beam of the second base station may be changed from the second transmission beam to a third transmission beam.

[0278] According to one embodiment, the controller receives first information from the second base station indicating that the transmission beam of the second base station is not changed from the second transmission beam to the third transmission beam, and may be configured to change the receiving beam of the FWA device based on the first information.

[0279] According to one embodiment, the controller may be configured to transmit capability information to the first base station indicating that the type of the UE (user equipment) is FWA.

[0280] According to one embodiment, a method performed by a fixed wireless access (FWA) device in a wireless communication system may include: receiving configuration information for interference management associated with a second base station from a first base station; identifying, based on the configuration information, whether the failure to receive a physical downlink shared channel (PDSCH) from the first base station is due to interference associated with the second base station when the reception of the PDSCH fails; and transmitting uplink control information (UCI) to the first base station, the UCI including information indicating whether the failure to receive the PDSCH is due to interference.

[0281] According to one embodiment, the setting information includes information regarding a threshold value for interference management, and the method may include the steps of identifying an average SINR (signal to interference plus noise ratio) value over a specified period and a SINR value at a point in time when the reception of the PDSCH is identified as having failed, and identifying that the failure of the reception of the PDSCH is based on the interference when the difference between the average SINR value and the SINR value exceeds the threshold value.

[0282] According to one embodiment, the setting information includes an indicator for indicating whether to report the UCI, and the method may include the steps of receiving a MAC (medium access control) CE (control element) from the first base station that enables the reporting of the UCI, and identifying information for interference management associated with the second base station based on the indicator and the MAC CE.

[0283] According to one embodiment, the configuration information includes an indicator for indicating whether to report the UCI, and the method may include the step of receiving downlink control information (DCI) for scheduling the PDSCH, and the step of identifying information for interference management associated with the second base station when the indicator of the configuration information indicates reporting the UCI and the DCI includes a field that triggers reporting the UCI.

[0284] According to one embodiment, if the failure of the reception of the PDSCH is based on the interference, the modulation and coding scheme (MCS) level for communication between the first base station and the FWA device is maintained, and if the failure of the reception of the PDSCH is not based on the interference, the MCS level may be lowered.

[0285] According to one embodiment, the UCI includes a negative acknowledgment (NACK) for the PDSCH and information indicating whether the failure of reception of the PDSCH is based on the interference, and if the information indicates that the failure is based on the interference, the transport block (TB) for the PDSCH is flushed, and if the information indicates that the failure is not based on the interference, the TB for the PDSCH can be stored in a buffer of the FWA device.

[0286] According to one embodiment, the method comprises the steps of: transmitting a random access preamble for a handover for interference management to the second base station when the failure of the reception of the PDSCH is based on the interference; receiving a random access response from the second base station; determining whether the difference between the RSRP (reference signals received power) value of the first transmission beam of the first base station and the RSRP value of the second transmission beam of the second base station is less than a threshold value; and, if the difference is less than the threshold value, transmitting information associated with the second transmission beam to the second base station, wherein the random access preamble may be set for interference management.

[0287] According to one embodiment, based on the information associated with the second transmission beam, the transmission beam of the second base station may be changed from the second transmission beam to a third transmission beam.

[0288] According to one embodiment, in a wireless communication system, a first base station includes a transceiver and a controller coupled to the transceiver, and the controller may be configured to transmit configuration information regarding interference management associated with a second base station to a fixed wireless access (FWA) device, and to receive uplink control information (UCI) from the FWA device, which includes information indicating whether the failure of the transmission of the physical downlink shared channel (PDSCH) to the FWA device is based on interference associated with the second base station, when the transmission of the physical downlink shared channel (PDSCH) to the FWA device fails.

[0289] According to one embodiment, a method performed by a first base station in a wireless communication system may include the steps of transmitting configuration information for interference management associated with a second base station to a fixed wireless access (FWA) device, and receiving uplink control information (UCI) from the FWA device, which includes information indicating whether the failure of the transmission of the physical downlink shared channel (PDSCH) to the FWA device is based on interference associated with the second base station, when the transmission of the physical downlink shared channel (PDSCH) to the FWA device fails.

[0290] Meanwhile, the present specification and drawings disclose preferred embodiments of the present invention. Although specific terms have been used, they are used merely in a general sense to facilitate the explanation of the technical content of the present invention and to aid in understanding the invention, and are not intended to limit the scope of the present invention. It is obvious to those skilled in the art that, in addition to the embodiments disclosed herein, other variations based on the technical concept of the present invention are possible.

Claims

1. In a fixed wireless access (FWA) device in a wireless communication system, transceiver; and It includes a controller combined with the above-mentioned transceiver, The above controller is: Receive configuration information for interference management associated with the second base station from the first base station, and If reception of the PDSCH (physical downlink shared channel) from the first base station fails, based on the configuration information, it is determined whether the failure of reception of the PDSCH is due to interference associated with the second base station, and An FWA device configured to transmit uplink control information (UCI) to the first base station, the UCI including information indicating whether the failure of reception of the PDSCH is based on the interference.

2. In Claim 1, The above setting information includes information regarding the threshold value for the interference management, and The above controller is: Identifying the average SINR (signal to interference plus noise ratio) value during a specified time and the SINR value at the point in time when it is identified that the reception of the PDSCH has failed, and An FWA device configured to identify that the failure of the reception of the PDSCH is based on the interference when the difference between the above average SINR value and the above SINR value exceeds the above threshold value.

3. In Claim 1, The above setting information includes an indicator for indicating whether to report the above UCI, and The above controller is: From the first base station, receive a MAC (medium access control) CE (control element) that enables reporting of the UCI, and An FWA device configured to identify information for interference management associated with the second base station based on the above indicator and the above MAC CE.

4. In Claim 1, The above setting information includes an indicator for indicating whether to report the above UCI, and The above controller is: Receive DCI (downlink control information) for scheduling the above PDSCH, and An FWA device configured to identify information for interference management associated with the second base station, wherein the indicator of the above-mentioned setting information indicates a report of the UCI and the DCI includes a field that triggers a report of the UCI.

5. In Claim 1, If the failure of the reception of the above PDSCH is based on the interference, the modulation and coding scheme (MCS) level for communication between the first base station and the FWA device is maintained, and An FWA device in which the MCS level is adjusted when the failure of the reception of the above PDSCH is not based on the interference.

6. In Claim 1, The above UCI includes a NACK (negative acknowledgment) for the above PDSCH and information indicating whether the failure of reception of the above PDSCH is based on the interference, and If the above information indicates that the above failure is based on the above interference, the TB (transport block) for the above PDSCH is flushed, and FWA device, wherein if the above information indicates that the above failure is not based on the above interference, the TB for the above PDSCH is stored in the buffer of the FWA device.

7. In Claim 1, The above controller is: If the failure of the reception of the above PDSCH is based on the interference, a random access preamble for a handover for interference management is transmitted to the second base station, and Receive a random access response from the second base station, and Determining whether the difference between the RSRP (reference signals received power) value of the first transmission beam of the first base station and the RSRP value of the second transmission beam of the second base station is smaller than a threshold value. If the above difference is smaller than the above threshold value, the second base station is configured to transmit information associated with the second transmission beam, and The above random access preamble is an FWA device configured for the above interference management.

8. In Claim 7, An FWA device in which the transmission beam of the second base station is changed from the second transmission beam to the third transmission beam based on the information associated with the second transmission beam.

9. In Claim 7, The above controller is: Receive first information from the second base station indicating that the transmission beam of the second base station is not changed from the second transmission beam to the third transmission beam, and An FWA device configured to change the receiving beam of the FWA device based on the above first information.

10. In Claim 1, The above controller is: An FWA device configured to transmit capability information indicating that the type of UE (user equipment) is FWA to the first base station.

11. A method performed by a fixed wireless access (FWA) device in a wireless communication system, A step of receiving configuration information for interference management associated with a second base station from a first base station; When reception of a physical downlink shared channel (PDSCH) from the first base station fails, a step of identifying, based on the configuration information, whether the failure of reception of the PDSCH is due to interference associated with the second base station; and A method comprising the step of transmitting uplink control information (UCI) to the first base station, the UCI including information indicating whether the failure of reception of the PDSCH is based on the interference.

12. In Claim 11, The above setting information includes information regarding the threshold value for the interference management, and The above method is: A step of identifying the average SINR (signal to interference plus noise ratio) value during a specified time and the SINR value at the point in time when the reception of the PDSCH is identified as having failed; and A method comprising the step of identifying that the failure of the reception of the PDSCH is based on the interference when the difference between the above average SINR value and the above SINR value exceeds the above threshold value.

13. In Claim 11, The above setting information includes an indicator for indicating whether to report the above UCI, and The above method is: A step of receiving a MAC (medium access control) CE (control element) from the first base station that enables reporting of the UCI; and A method comprising the step of identifying information for interference management associated with the second base station based on the indicator and the MAC CE.

14. In a first base station of a wireless communication system, transceiver; and It includes a controller combined with the above-mentioned transceiver, The above controller is: Transmit configuration information for interference management associated with the second base station to the FWA (fixed wireless access) device, and A first base station configured to receive uplink control information (UCI) from the FWA device, which includes information indicating whether the failure of the transmission of the physical downlink shared channel (PDSCH) to the FWA device is based on interference associated with the second base station, when the transmission of the physical downlink shared channel (PDSCH) to the FWA device fails.

15. A method performed by a first base station in a wireless communication system, A step of transmitting configuration information for interference management associated with a second base station to a fixed wireless access (FWA) device; and A method comprising the step of receiving uplink control information (UCI) from the FWA device, which includes information indicating whether the failure of the transmission of the physical downlink shared channel (PDSCH) to the FWA device is based on interference associated with the second base station, when the transmission of the physical downlink shared channel (PDSCH) to the FWA device fails.

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