Method and apparatus for controlling inter-cell interference in wireless communication system

Abstract

The present disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate. According to various embodiments disclosed herein, a method performed by a serving base station in a wireless communication system may comprise the steps of: receiving information on an aggregated slot from an aggregated slot management device; aggregating and scheduling traffic to be transmitted during a specific interval into the aggregation slot based on the information on the aggregation slot; determining adaptive modulation and coding (AMC) parameters for the aggregated time slot and the non-aggregated time slot, respectively; and transmitting the traffic of the aggregated time slot using the determined AMC parameter. Various other embodiments identified by the present specification are possible.

Description

Technical Field

[0001] The present disclosure relates to a wireless communication system, and more particularly, to a method and apparatus for controlling inter-cell interference in a wireless communication system. Background Art

[0002] 5G mobile communication technology defines a wide frequency band, making high transmission rates and new services possible, and can be implemented not only in frequency bands "below 6 GHz" such as 3.5 GHz, but also in frequency bands "above 6 GHz" called millimeter waves including 28 GHz and 39 GHz. In addition, in order to achieve a transmission rate 50 times that of 5G mobile communication technology and an ultra-low latency of one-tenth of 5G mobile communication technology, it has been considered to implement 6G mobile communication technology (called a super 5G system) in the terahertz (THz) frequency band (e.g., 95 GHz to 3 THz frequency band).

[0003] At the beginning of the development of 5G mobile communication technology, in order to support services and meet the performance requirements related to enhanced mobile broadband (eMBB), ultra-reliable low-latency communication (URLLC) and massive machine-type communication (mMTC), standardization of the following items has been ongoing: beamforming and massive MIMO for alleviating radio wave path loss and increasing the radio wave transmission distance in millimeter waves, dynamic operation of supporting parameter sets (e.g., operating multiple subcarrier intervals) to effectively utilize millimeter wave resources and time slot formats, initial access technology for supporting multi-beam transmission and broadband, definition and operation of BWP (bandwidth part), new channel coding methods for large data volume transmission such as LDPC (low-density parity check) codes and polar codes for high-reliability transmission of control information, L2 preprocessing, and network slicing for providing dedicated networks dedicated to specific services.

[0004] The development of 5G mobile communication systems will lay the foundation not only for the development of new waveforms for providing terahertz band coverage for 6G mobile communication technology, such as multi-antenna transmission technology of full-dimensional MIMO (FD-MIMO), array antennas and large antennas, metamaterial-based lenses and antennas for improving terahertz band signal coverage, and high-dimensional spatial multiplexing technology using OAM (orbital angular momentum) and RIS (reconfigurable smart surface), but also for the development of full-duplex technology for increasing the frequency efficiency of 6G mobile communication technology and improving system networks, AI-based communication technology for achieving system optimization from the design stage by utilizing satellites and AI (artificial intelligence) and internalizing end-to-end AI support functions, and next-generation distributed computing technology for realizing services with a complexity that exceeds the operating capability limits of UE by utilizing ultra-high performance communication and computing resources.

[0005] In communication / broadcasting systems, link performance may be significantly degraded due to various types of noise, fading phenomena, and inter-symbol interference (ISI) of the channel. Therefore, in order to realize high-speed digital communication / broadcasting systems requiring high data throughput and reliability such as next-generation mobile communications, digital broadcasting, and portable Internet, it is necessary to develop technologies to overcome noise, fading, and inter-symbol interference. Summary of the invention

[0006] Technical issues

[0007] Various embodiments of the present disclosure provide an apparatus and method, performed by a serving cell, for controlling inter-cell interference in a wireless communication system.

[0008] Solution

[0009] According to various embodiments of the present disclosure, a method performed by a serving base station in a wireless communication system may include: receiving information about an aggregated time slot from an aggregated time slot management device, aggregating traffic to be sent during a predetermined interval into the aggregated time slot based on the information about the aggregated time slot, and scheduling the aggregated traffic, determining separate adaptive modulation and coding (AMC) for the aggregated time slot and the non-aggregated time slot, and sending the traffic to the terminal within the aggregated time slot by using the determined AMC.

[0010] According to various embodiments of the present disclosure, a device of a serving base station in a wireless communication system may include a transceiver and at least one processor, wherein the at least one processor is configured to receive information about aggregated time slots from an aggregated time slot management device, aggregate traffic to be sent during a predetermined interval into aggregated time slots and schedule aggregated traffic based on the information about the aggregated time slots, determine separate adaptive modulation and coding (AMC) for aggregated time slots and non-aggregated time slots, and send the traffic of the aggregated time slots to the terminal by using the determined AMC.

[0011] According to various embodiments of the present disclosure, a method performed by a neighboring base station in a wireless communication system may include: receiving information about an aggregate time slot from an aggregate time slot management device, aggregating traffic to be sent during a predetermined interval into an aggregate time slot based on the information about the aggregate time slot, scheduling the aggregate traffic, and sending the traffic to a terminal within the aggregate time slot.

[0012] According to various embodiments of the present disclosure, a device of a neighboring base station in a wireless communication system may include a transceiver and at least one processor, wherein the at least one processor is configured to receive information about an aggregated time slot from an aggregated time slot management device, aggregate traffic to be sent during a predetermined interval into the aggregated time slot based on the information about the aggregated time slot and schedule the aggregated traffic, and send the traffic to a terminal within the aggregated time slot. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 An example of a wireless resource area in a wireless communication system according to various embodiments of the present disclosure is shown;

[0014] Figure 2 An example of radio resource allocation when aggregated time slots are configured according to various embodiments of the present disclosure is shown;

[0015] Figure 3 An example of radio resource allocation when aggregated time slots are configured according to various embodiments of the present disclosure is shown;

[0016] Figure 4 An example of radio resource allocation when aggregated time slots are configured according to various embodiments of the present disclosure is shown;

[0017] Figure 5 An example of radio resource allocation when aggregated time slots are configured according to various embodiments of the present disclosure is shown;

[0018] Figure 6 shows the buffer occupancy (BO) state of a base station when an aggregated time slot is configured according to various embodiments of the present disclosure;

[0019] Figure 7 A block diagram illustrating resource allocation according to various embodiments of the present disclosure is shown;

[0020] Figure 8 An example of the number of code blocks (CBs) and RBs per CB according to a modulation coding schedule (MCS) level according to various embodiments of the present disclosure is shown;

[0021] Fig. 9 A flowchart illustrating operations for inter-cell interference control between a cell and an aggregated time slot management device according to various embodiments of the present disclosure is shown;

[0022] Fig.10 The operation of a serving base station according to various embodiments of the present disclosure is shown;

[0023] Fig.11 The operation of an interfering base station according to various embodiments of the present disclosure is shown;

[0024] Fig.12 A graph showing time slot usage versus period of aggregated time slots according to various embodiments of the present disclosure;

[0025] Fig.13 A graph showing time slot usage versus period of aggregated time slots according to various embodiments of the present disclosure; and

[0026] Fig.14 A graph of data throughput versus signal-to-noise ratio (SNR) is shown according to various embodiments of the present disclosure.

[0027] Fig.15 The structure of a base station in a wireless communication system according to various embodiments of the present disclosure is shown.

[0028] With regard to the description of the drawings, the same or similar reference symbols may be used to refer to the same or similar elements. DETAILED DESCRIPTION

[0029] Various aspects of the claimed subject matter are now described with reference to the accompanying drawings, wherein like reference numerals are generally used to refer to like elements throughout. In the following description, for the purpose of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more aspects. However, it is apparent that these aspects can be practiced without these specific details.

[0030] The terms used in the present disclosure are only used to describe specific embodiments, and may not be intended to limit the scope of other embodiments. Singular expressions may include plural expressions unless they are clearly different in context. The terms used herein, including technical and scientific terms, may have the same meaning as the meanings generally understood by those skilled in the art to which the present disclosure belongs. The terms defined in a general dictionary may be interpreted as having the same meaning as the contextual meanings in the relevant technical field, and unless clearly defined in the disclosure, should not be interpreted as having an ideal or overly formal meaning. In some cases, even the terms defined in the present disclosure should not be interpreted as excluding embodiments of the present disclosure.

[0031] In the following description, terms referring to signals (e.g., messages, signals, signaling, sequences, and streams), terms referring to resources (e.g., symbols, time slots, subframes, radio frames, subcarriers, resource elements (REs), resource blocks (RBs), bandwidth parts (BWPs), and opportunities), terms referring to operations (e.g., steps, methods, processes, and procedures), terms referring to data (e.g., information, parameters, variables, values, bits, symbols, and codewords), terms referring to channels, terms referring to control information (e.g., downlink control information (DCI), media access control control elements (MAC CEs), and radio resource control (RRC) signaling), terms referring to network entities, terms referring to device elements, and the like are all used illustratively for the convenience of description. Therefore, the present disclosure is not limited to the terms used below, and other terms with equivalent technical meanings may be used.

[0032] Various aspects associated with wireless terminals and / or base stations are described herein. A wireless terminal may refer to a device that provides voice and / or data connections to a user. A wireless terminal may be connected to a computing device such as a laptop or desktop computer, or may be a self-contained device such as a personal digital assistant (PDA). A wireless terminal may also be referred to as a system, a subscriber unit, a subscriber station, a mobile station, a mobile phone, a mobile device, a remote station, a remote terminal, an access terminal, a user terminal, a terminal, a wireless communication device, a user agent, a user device, or a user device. A wireless terminal may be a subscriber station, a wireless device, a cellular phone, a PCS phone, a cordless phone, a session initiation protocol (SIP) phone, a wireless local loop (WLL) station, a personal digital assistant (PDA), a handheld device with wireless connection capability, or other processing devices connected to a wireless modem. A base station (e.g., an access point) may refer to a device in an access network that communicates with a wireless terminal through an air interface through one or more sectors. A base station may act as a router between a wireless terminal and the rest of the access network by converting received air interface frames into IP packets, and the access network may include an Internet Protocol (IP) network. The base station also coordinates attribute management of the air interface.

[0033] The terms used in the present disclosure are only used to describe specific embodiments and may not be intended to limit the scope of other embodiments. Singular expressions may include plural expressions unless they are clearly different in context. All terms used herein, including technical and scientific terms, may have the same meaning as the meanings commonly understood by those skilled in the art to which the present disclosure belongs. Terms defined in general dictionaries may be interpreted as having the same meanings as the contextual meanings of the relevant technical field, and unless clearly defined in the disclosure, should not be interpreted as having ideal or overly formal meanings. In some cases, even the terms defined in the present disclosure should not be interpreted as excluding embodiments of the present disclosure.

[0034] When two base stations are set adjacent to each other and the coverage of the two base stations partially overlaps, a strong downlink (DL) signal from one base station can cause interference to a terminal served by another base station. That is, inter-cell interference (ICI) can occur between a serving cell formed by a base station and an interfering cell adjacent to the serving cell, causing interference.

[0035] Unlike the LTE system, the NR system is designed based on the Ultra Lean principle to minimize always-on transmission, and therefore, if there is no actual data to be sent, there is no interference with neighboring cells. Therefore, the control of ICI in the 5G NR system is attracting attention as one of the representative technologies for improving network performance.

[0036] Figure 1 An example of a wireless resource area in a wireless communication system according to various embodiments of the present disclosure is shown.

[0037] In various embodiments of the present disclosure, the wireless resource region may include a structure in the time-frequency domain. According to an embodiment, the wireless communication system may include an NR communication system.

[0038] Reference Figure 1 , in the wireless resource region, the horizontal axis represents the time domain, and the vertical axis represents the frequency domain. The length of the wireless frame 104 is 10 ms. The wireless frame 104 may be a time domain interval configured by 10 subframes. The length of the subframe 203 is 1 ms. The configuration unit in the time domain may be an orthogonal frequency division multiplexing (OFDM) and / or DFT-s-OFDM (Discrete Fourier Transform (DFT)-Spread-OFDM) symbol, and N symb OFDM symbols and / or DFT-s-OFDM symbols 101 may be aggregated to configure one time slot 102. In various embodiments, the OFDM symbol may include a symbol for the case of transmitting and receiving a signal by using an OFDM multiplexing scheme, and the DFT-s-OFDM symbol may include a symbol for the case of transmitting and receiving a signal by using a DFT-s-OFDM or a single carrier frequency division multiple access (SC-FDMA) multiplexing scheme. The minimum transmission unit in the frequency domain is a subcarrier, and the carrier bandwidth configuring the resource grid may be composed of a total of N sc BW The subcarriers 105 are configured. In addition, in the present disclosure, for the convenience of description, the embodiments regarding downlink signal transmission and reception are described, but this is also applicable to the embodiments regarding uplink signal transmission and reception.

[0039] In some embodiments, the number of time slots 102 configuring one subframe 103 and the length of the time slot 102 may vary depending on the subcarrier spacing. Such a subcarrier spacing may be referred to as a parameter set (μ). That is, the subcarrier spacing, the number of time slots included in a subframe, the time slot length, and the subframe length may be variably configured. For example, in an NR communication system, when the subcarrier spacing (SCS) is 15kHz, one time slot 102 may configure one subframe 103, and each length of the time slot 102 and the subframe 103 may be 1ms. In addition, for example, if the subcarrier spacing is 30kHz, two time slots may configure one subframe 103. In this case, the length of the time slot is 0.5ms, and the length of the subframe is 1ms.

[0040] In some embodiments, the subcarrier spacing, the number of time slots included in a subframe, the time slot length, and the subframe length may be variably applied depending on the communication system. For example, in the case of an LTE system, the subcarrier spacing is 15kHz, two time slots configure one subframe, and in this case, the length of the time slot may be 0.5ms, and the length of the subframe may be 1ms. As another example, in the case of an NR system, the subcarrier spacing (μ) may be one of 15kHz, 30kHz, 60kHz, 120kHz, and 240kHz, and according to the subcarrier spacing (μ), the number of time slots included in one subframe may be 1, 2, 4, 8, and 16.

[0041] The basic unit of resources in the time-frequency domain may be a resource element (RE) 106, and the resource element 106 may be represented as an OFDM symbol index and a subcarrier index. A resource block may include a plurality of resource elements. In an NR system, a resource block (RB) (or physical resource block (PRB)) 107 may be defined as N in the frequency domain. SCRB The number of subcarriers can be N SCRB =12. The frequency domain may include common resource blocks (CRBs). Physical resource blocks (PRBs) may be defined in bandwidth parts (BWPs) on the frequency domain. The number of CRBs and PRBs may be determined differently depending on the subcarrier spacing. In the LTE system, an RB may be defined as N in the time domain. symb consecutive OFDM symbols and N in the frequency domain SCRB consecutive subcarriers.

[0042] In NR and / or LTE systems, scheduling information for downlink data or uplink data may be sent from a base station to a UE via downlink control information (DCI). In various embodiments, DCI may be defined according to various formats, and each format may indicate whether the DCI includes scheduling information (e.g., UL authorization) for uplink data, whether the DCI includes scheduling messages (DL resource allocation) for downlink data, whether the DCI is a compact DCI with small-size control information, whether the DCI is a fallback DCI, whether spatial multiplexing using multiple antennas is applied, and / or whether the DCI is a DCI for power control. For example, NR DCI format 1_0 or NR DCI format 1_1 may include scheduling for downlink data. In addition, for example, NR DCI format 0_0 or NR DCI format 0_1 ​​may include scheduling for uplink data.

[0043] As mentioned above, Figure 1 An example of a downlink and uplink time slot structure in a wireless communication system is shown. In particular, Figure 1 The structure of the resource grid of the 3GPP NR system is shown. Figure 1 , a time slot may include multiple orthogonal frequency division multiplexing (OFDM) symbols in the time domain and multiple resource blocks (RBs) in the frequency domain. A signal may be configured by a portion or all of a resource grid. In addition, the number of OFDM symbols contained in a time slot may generally vary depending on the length of a cyclic prefix (CP). Figure 1 In the example, for ease of description, a case where one time slot is configured by 14 OFDM symbols is shown, but in the case of the signal mentioned in the present disclosure, the configuration of the symbols is not specified. In addition, the modulation scheme of the generated signal is not limited to a specific value of quadrature amplitude modulation (QAM), and can follow the modulation schemes of various communication standards such as binary phase shift keying (BPSK) and quadrature phase shift keying (QPSK).

[0044] Although various embodiments of the present disclosure are described based on an LTE communication system or an NR communication system, the content of the present disclosure is not limited thereto and can be applied in various wireless communication systems for transmitting downlink or uplink control information. In addition, it is obvious that in addition to the licensed frequency band, the content of the present disclosure can be applied to the unlicensed frequency band as needed.

[0045] In the following description of the present disclosure, higher layer signaling may be performed, or a higher layer signal may be sent by a signal sending method in which a base station sends a signal to a user equipment (UE) by using a downlink data channel of a physical layer, or a UE sends a signal to a base station by using an uplink data channel of a physical layer. According to an embodiment, the higher layer signaling may include at least one of a method of sending a signal by a radio resource control (RRC) signaling, a signaling according to an F1 interface between a centralized unit (CU) and a distributed unit (DU), or a medium access control (MAC) control element (MAC CE). In addition, according to an embodiment, the higher layer signaling or the higher layer signal may include system information commonly sent to multiple UEs, such as a system information block (SIB).

[0046] In a 5G wireless communication system, a synchronization signal block (SSB) (or referred to as an SS block, SS / PBCH block, etc.) may be sent for initial access, and the synchronization signal block may be configured by a primary synchronization signal (PSS), a secondary synchronization signal (SSS), and a physical broadcast channel (PBCH). In the initial access step when the UE first accesses the system, the UE may obtain downlink time domain and frequency domain synchronization from the synchronization signal through a cell search process, and obtain a cell ID. The synchronization signal may include a PSS and an SSS. The UE may receive a PBCH including a master information block (MIB) from a base station to obtain basic parameter values ​​and system information related to transmission and reception, such as system bandwidth or related control information. The UE may obtain a system information block (SIB) by performing decoding on a physical downlink control channel (PDCCH) and a physical downlink shared channel (PDSCH) based on the received PBCH. Thereafter, the UE may exchange identities with the base station through a random access step, and may initially access the network through steps such as registration and authentication.

[0047] As described above, one time slot may include 14 symbols, and in the 5G communication system, the uplink-downlink configuration of symbols and / or time slots may be configured in three steps.

[0048] In the first method, the uplink-downlink of symbols and / or time slots can be semi-statically configured through cell-specific configuration information through system information in units of symbols. More specifically, the cell-specific uplink-downlink configuration information through system information may include uplink-downlink mode information and reference subcarrier information. The uplink-downlink mode information may indicate the pattern periodicity, the number of consecutive downlink time slots from the start of each pattern, the number of symbols in the next time slot, the number of consecutive uplink time slots from the end of the pattern, and the number of symbols in the next time slot. Time slots and symbols that are not indicated as uplink and downlink may be determined as flexible time slots / symbols.

[0049] In the second method, through user-specific configuration information via dedicated higher layer signaling, a flexible time slot or a time slot including flexible symbols can be indicated by the number of consecutive downlink symbols from the start symbol of each time slot and the number of consecutive uplink symbols from the end of the time slot, or indicated as the downlink or uplink of the entire time slot.

[0050] In the third method, in order to dynamically change the downlink signal transmission interval and the uplink signal transmission interval, the symbols indicated as flexible symbols in each time slot (e.g., symbols not indicated as downlink and uplink) can be indicated as downlink symbols, uplink symbols, or flexible symbols respectively through a time slot format indicator (SFI) included in the downlink control channel. The time slot format indicator can select an index from a table (e.g., 3GPP TS 38.213 Table 11.1.1-1) in which uplink-downlink configurations of 14 symbols in one time slot are preconfigured.

[0051] Figure 2 An example of radio resource allocation when aggregated time slots are configured according to various embodiments of the present disclosure is shown.

[0052] Reference Figure 2 , the horizontal axis represents the time domain, and the vertical axis represents the frequency domain. The division unit in the time domain may be a time slot, and the division unit in the frequency domain may be a subcarrier.

[0053] Among the wireless resources allocated in the serving cell, there are wireless resources (interfered resources) that are interfered by the traffic of the neighboring cells. The interference traffic of the neighboring cells (i.e., the traffic of the neighboring cells that acts as interference to the serving cell) may be dispersed and may exist in multiple time slots. Figure 2 , in the conventional case 210, the wireless resources interfered by the traffic of the neighboring cells may be distributed over a total of 7 time slots with reference to the time axis.

[0054] According to an embodiment of the present disclosure, in order to control inter-cell interference, a specific time slot into which the traffic of the neighboring cells will be aggregated and allocated can be configured in the time domain. The specific time slot in the time domain can be called an aggregated time slot or an interference aggregated time slot. When an aggregated time slot is configured, the traffic sent within a predetermined interval can be aggregated and allocated to the aggregated time slot.

[0055] The aggregation time slot management device can pre-configure the aggregation time slot and send information about the aggregation time slot to the entire cell. Therefore, the positions of the aggregation time slots of the cells managed by the aggregation time slot management device can be aligned identically. Specifically, the aggregation time slot for each cell can include the same operating interval and offset configuration.

[0056] According to an embodiment of the present disclosure, the radio resources to which the cell traffic is allocated may be aggregated into a preconfigured aggregation time slot and scheduled. Figure 2 In the case 220 where the aggregated time slot is configured, the radio resources to which the cell traffic is allocated may be distributed over a total of two time slots 201 and 202 with reference to the time axis. In this case, the frequency of time slots to which nothing is allocated (ie, time slots to which no traffic is allocated) may be increased.

[0057] According to an embodiment of the present disclosure, when aggregated time slots are configured, time slots acting as interference can form a larger RB than before. However, in the NR system, even when decoding of only one code block (CB) fails, the entire transport block (TB) including the CB may be regarded as a transmission failure, so the size of the RB may have a smaller impact on the throughput of data transmission. Therefore, even when the size of the RB acting as interference is increased by configuring aggregated time slots, the adverse effect on the data transmission throughput is small. On the contrary, the number of time slots acting as interference is reduced, so the total amount of interference is reduced, thereby improving the performance of data transmission.

[0058] According to an embodiment of the present disclosure, when aggregated time slots are configured, the probability of inter-cell interference among neighboring cells in the aggregated time slots increases, but the probability of inter-cell interference among neighboring cells in other time slots (hereinafter referred to as non-aggregated time slots) decreases, and thus time zones with a high probability of inter-cell interference and time zones with a low probability of inter-cell interference can be distinguished.

[0059] Figure 3 An example of radio resource allocation when aggregated time slots are configured according to various embodiments of the present disclosure is shown.

[0060] Reference Figure 3 , the horizontal axis in the figure represents the time domain, and the vertical axis represents the frequency domain. The division unit in the time domain may be a time slot, and the division unit in the frequency domain may be a subcarrier.

[0061] According to an embodiment of the present disclosure, an aggregated time slot management device may aggregate the traffic of a cell and configure the traffic to be allocated to a specific time slot in the time domain. In this case, the specific time slot in the time domain may be referred to as an aggregated time slot. A cell managed by an aggregated time slot management device may aggregate the traffic of a cell based on information about such an aggregated time slot and allocate it to an aggregated time slot. The operation of configuring an aggregated time slot by an aggregated time slot management device to control inter-cell interference in the time domain may be referred to as time domain interference time slot alignment (TDIA).

[0062] The aggregation time slot management device can preconfigure and send information about the aggregation time slot to the entire cell. Therefore, the positions of the aggregation time slots of the cells managed by the aggregation time slot management device can be aligned identically. Specifically, the aggregation time slot for each cell can include the same operating interval and offset configuration.

[0063] refer to Figure 3, when the aggregation time slot is not configured, randomly distributed traffic from neighboring cells that are adjacent to the serving cell to cause inter-cell interference may affect the serving cell. The serving cell may be affected by interference according to the time slots in which the traffic within the neighboring cells is distributed. On the other hand, when the aggregation time slot is configured, the traffic of the cell may be aggregated and allocated to the aggregation time slot of the cell. When the traffic of the neighboring cells that acts as interference to the aggregation time slot is aggregated and allocated, the interval of the non-aggregation time slot to which the traffic that acts as interference to the cell is allocated may be longer. The non-aggregation time slot may refer to a time slot other than the configured aggregation time slot, and may be a time slot where the possibility of inter-cell interference occurring is low.

[0064] That is, when TDIA is in operation, the serving cell can send traffic to the UE in more time slots in which it does not act as interference, compared to when TDIA is not in operation, and thus the serving cell can obtain the effect of being less affected by inter-cell interference of the interfered cell.

[0065] According to an embodiment of the present disclosure, when an aggregated time slot is configured, the probability of inter-cell interference of neighboring cells in the aggregated time slot increases, but the probability of inter-cell interference of neighboring cells in other time slots (hereinafter referred to as non-aggregated time slots) can be reduced. On the other hand, when an aggregated time slot is not configured, the probability of inter-cell interference of neighboring cells can occur randomly in each time slot.

[0066] Figure 4 An example of radio resource allocation when aggregated time slots are configured according to various embodiments of the present disclosure is shown.

[0067] According to an embodiment of the present disclosure, when an aggregation timeslot is configured, the cell may schedule traffic to be sent within a predetermined interval to the configured aggregation timeslot. More specifically, when traffic occurs, the cell may wait without sending traffic until the configured aggregation timeslot is reached. Since such traffic may act as interference to neighboring cells, the traffic may be aggregated and allocated to the aggregation timeslot and sent to the UE. That is, the traffic may be delayed until it reaches the aggregation timeslot and may not be sent to the UE.

[0068] In addition, when no more traffic can be allocated to the aggregated timeslot, the traffic can be allocated to the next timeslot of the aggregated timeslot. In this case, the next timeslot of the aggregated timeslot can be a non-aggregated timeslot.

[0069] Reference Figure 4, when the aggregation time slot is not configured and traffic is transmitted, the traffic of the cell is transmitted to UE 1 to UE 3, and the number of aggregation time slots to which the cell traffic is allocated may be 12 (401 to 403, 406, 407, 409, 410, 413, 414, and 416 to 418). On the other hand, when the aggregation time slot is configured and traffic is aggregated into the aggregation time slot and transmitted, the number of aggregation time slots may be reduced to 7 (404, 405, 408, 411, 412, 415, and 419) compared to the number of aggregation time slots when the aggregation time slot is not configured.

[0070] According to an embodiment of the present disclosure, when a heavy traffic UE exists in a serving cell and a light traffic UE exists in an interfering cell, the traffic of both the serving cell and the interfering cell can be aggregated and allocated to an aggregated time slot. In this case, the traffic exceeding the traffic of the interfering cell's aggregated time slot allocated to the serving cell can be less affected by inter-cell interference due to the traffic of the interfering cell. For example, referring to Figure 4 , when UE 3 is present in the serving cell and UE 1 or UE 2 is present in the interfering cell, the traffic of both the serving cell and the interfering cell can be aggregated into the aggregated time slots 404 and 405. In this case, the traffic of UE 3 allocated to the time slot 405 exceeds the traffic of UE 1 or UE 2 allocated to the aggregated time slot 404, which may not be affected by the interference. Therefore, UE 3 located in the serving cell can obtain as much performance gain as the traffic of the time slot 405 which is not affected by the interference.

[0071] refer to Figure 4 , when the aggregated time slot is not configured and traffic is sent, the probability of inter-cell interference occurring in each time slot exists randomly for each time slot, but when traffic is aggregated into the aggregated time slot and sent, the probability of inter-cell interference occurring in the neighboring cells in the aggregated time slot is higher, while the probability of inter-cell interference occurring in the neighboring cells in the non-aggregated time slot is lower, so that the time zone with a high probability of inter-cell interference and the time zone with a low probability of inter-cell interference can be distinguished. In addition, even when the size of the interfering RB is large, the decoding performance of the CB may not be significantly affected. That is, even when the size of the RB acting as interference is increased by configuring the aggregated time slot, the adverse effect on the data transmission throughput is small. On the contrary, the number of time slots acting as interference is reduced, so the total amount of interference is reduced, thereby improving the performance of data transmission.

[0072] According to an embodiment of the present disclosure, since the probability of inter-cell interference occurring in an aggregated timeslot is high, a separate adaptive modulation and coding (AMC) may be determined for each aggregated timeslot and a timeslot other than the aggregated timeslot (hereinafter referred to as a non-aggregated timeslot).

[0073] The maximum expected value of the downlink data throughput from the cell to the UE is expressed as in the following <Equation 1>.

[0074] [Formula 1]

[0075]

[0076] stap 1 (r 1 )+(1-a)p 2 (r 2 )≥p t

[0077] p 1 and p 2 It can refer to the probability of data transmission in the absence of inter-cell interference, and r 1 and r 2 It can refer to the TBS determined by applying AMC in the absence of inter-cell interference. a can refer to the probability of inter-cell interference occurring. p t can refer to the target probability of successful delivery and can be defined as p t =1-target block error rate (BLER).

[0078] Generally speaking, it may be difficult to know whether there is inter-cell interference in each time zone in a wireless communication system. Therefore, the same AMC determination is applied regardless of whether there is inter-cell interference. In this case, <Formula 1> can be expressed as the following <Formula 2>.

[0079] [Formula 2]

[0080]

[0081] stp(r)≥p t

[0082] r can refer to replace r n The value of p can be expressed as p = ap 1 +(1-a)p 2 In order to determine the maximum data throughput, information about the probability of successful transmission p may be required. However, due to inter-cell interference and mobility of wireless resources, it may be difficult to determine the information about p. Therefore, the maximum data throughput may be determined by reducing the probability a of the occurrence of inter-cell interference.

[0083] According to an embodiment of the present disclosure, when a separate AMC determines an aggregated time slot and a non-aggregated time slot to which traffic applied to a neighboring cell serving as interference is aggregated and allocated, the occurrence probability of inter-cell interference may be indirectly reduced.

[0084] If the past transmission in the aggregated time slot is an ACK, the base station can increase the signal to interference and noise ratio (SINR) of the aggregated time slot, and if the past transmission in the aggregated time slot is a NACK, the SINR can be reduced. If the past transmission in the non-aggregated time slot is an ACK, the base station can increase the SINR of the non-aggregated time slot, and if the past transmission in the non-aggregated time slot is a NACK, the base station can reduce the SINR. By increasing the strength of the received signal of the uplink, the SINR can be increased.

[0085] An adaptive modulation and coding selection (MCS) level is selected based on the signal SINR ratio of the channel for transmitting and receiving data. A low MCS level is applied to aggregated time slots and a high MCS level is applied to non-aggregated time slots, so that a low data transmission rate can be applied to aggregated time slots where the frequency of inter-cell interference is expected to be high.

[0086] The detailed operation of configuring an aggregated time slot to aggregate and distribute traffic of a neighboring cell acting as interference, and applying separate AMC determination to the aggregated time slot and the non-aggregated time slot can be represented by the algorithm in below.

[0087]

Table 1

[0088]

[0089]

[0090] Figure 5 An example of radio resource allocation when aggregated time slots are configured according to various embodiments of the present disclosure is shown.

[0091] Reference Figure 5 , showing traffic allocation in time slot indexes 0 to 11. Traffic may occur in the buffer occupancy (BO) of the base station in time slot index 2 510. When the aggregated time slot is not configured, the base station may allocate traffic acting as interference to time slot indexes 2, 3, 5 to 8, 10, and 11 by combining short BO and heavy BO, and send the traffic to the UE. That is, when the aggregated time slot is not configured, traffic acting as interference is randomly allocated, and a total of 8 time slots (time slot indexes 2, 3, 5 to 8, 10, and 11) may be affected by interference.

[0092] On the other hand, when the aggregation time slot is configured, the traffic acting as interference can be aggregated and allocated to the aggregation time slot. Figure 5, the aggregated time slot is configured as time slot index 5 520. In the case of short BO, the base station can allocate and send traffic in time slot index 5 520 without sending traffic to the UE in time slot index 2 510 where the traffic has reached BO. In addition, in the case of heavy BO, the base station can allocate traffic in time slot index 5 520 without sending traffic to the UE in time slot index 2 510 where the traffic has reached BO, and when the traffic exceeds the allocated radio resources, the excess traffic can be allocated to the time slot for excess traffic after time slot index 5 520. That is, when the aggregated time slot is configured, the traffic acting as interference is aggregated and allocated to the aggregated time slot, and a total of 6 time slots (time slot indexes 5 to 8, 10 and 11) can be affected by interference.

[0093] That is, when the aggregated time slot is configured and the traffic is aggregated, sorted and allocated to the aggregated time slot, the number of time slots to which the traffic causing interference is allocated can be reduced compared to when the aggregated time slot is not configured. Therefore, the probability of interference occurring is reduced, and the data communication performance of the network can be improved.

[0094] Figure 6 1 shows the BO state of the base station when the aggregated time slot is configured according to various embodiments of the present disclosure. Specifically, Figure 6 The BO state of the base station when performing TDIA operation is shown.

[0095] Reference Figure 6 , when the buffer occupancy (BO) of the base station is empty, this may be referred to as an empty state. If traffic occurs in the BO of the base station in the empty state, the state of the BO of the base station may indicate that the BO of the base station is filled with traffic that has occurred (non-zero BO). In this case, the BO state of the base station may be referred to as a waiting state. In this case, the BO of the base station may remain in a waiting state without sending traffic to the UE until the traffic arrives at the aggregated timeslot.

[0096] When the traffic that has occurred in the BO of the base station arrives at the aggregated timeslot, the state of the BO can be changed to the ready state. In this case, the traffic that has arrived at the aggregated timeslot can be sent to the UE. Even if additional traffic occurs thereafter, the traffic can be allocated to the aggregated timeslot and sent to the UE, and thus the ready state can be maintained. The detailed operation of the TDIA operation can be represented by the algorithm in below.

[0097]

Table 2

[0098]

[0099]

[0100] Figure 7 A block diagram of allocating resources according to various embodiments of the present disclosure is shown.

[0101] Reference Figure 7 , the horizontal axis represents the frequency domain and the vertical axis represents the time domain.

[0102] In the NR system, one transport block (hereinafter referred to as TB) may include multiple code blocks (hereinafter referred to as CBs). A cyclic redundancy check (CRC) (not shown) may be added to the back end or front end of a TB that is desired to be transmitted in the uplink or downlink. The CRC may have 16 bits or 24 bits or a fixed number of bits, or a variable number of bits according to channel conditions, and may be used to determine whether channel coding is successful. In the NR system, a TB may be configured by multiple CBs without the need for a separate partitioning process. Even when a CRC failure occurs only in one CB, a NACK determination of transmission failure of the entire TB may be made.

[0103] The larger the size of a transport block (TB size, TBS), the greater the number of CBs may be. Therefore, the number of resource blocks that each transport block may occupy may be reduced. As the TBS increases, it may be susceptible to interference from a small number of RBs. That is, as the TBS increases, even when a CRC failure occurs in one of a plurality of CBs included in a TB due to interference, the entire TB may be affected by interference. For example, Figure 7 As shown, when a CRC failure occurs in at least one CB among CB#3 to CB#5 configuring one TB, a NACK determination of transmission failure of the corresponding TB may be made.

[0104] According to an embodiment of the present disclosure, as the TBS increases, it is susceptible to interference from the RB, and therefore, compared with when the traffic of the neighboring cell acting as interference is distributed in multiple time slots, the traffic of the neighboring cell acting as interference is aggregated in a specific aggregation time slot within a predetermined time period and can be less affected by the interference. That is, even when the size of the RB acting as interference increases, if the traffic of the neighboring cell acting as interference is aggregated and allocated to the aggregation time slot, the size of the RB acting as interference increases, but the performance difference may not be significant because regardless of the size of the RB, the entire TB to which the corresponding CB belongs will be affected by the interference.

[0105] Figure 8 Examples of the number of code blocks (CBs) and RBs per CB according to a modulation coding schedule (MCS) level according to various embodiments of the present disclosure are shown.

[0106] according to Figure 8 , the number of CBs that can exist can be determined according to the level of the rank indicating the number of transmission layers and the MCS level. For example, in the case of MCS27 and rank 4, the number of CBs can be 129. In addition, according to Figure 8, the RBs occupied by each CB can be determined. For example, in the case of MCS27 and rank 4, each CB can occupy 23 RBs. According to an embodiment of the present disclosure, Figure 8 In the case of MCS27 and rank 4 in , when the traffic size of the neighboring cell acting as interference exceeds 23 RBs, as long as interference exceeding one CB of the configured TB occurs, a NACK decision can be made for the entire TB including the corresponding CB, just as if interference occurs. That is, when interference exceeding the size of the RB occupied by each CB occurs, the decoding performance of the CB may not be significantly affected even if the size of the interfering RB is large. That is, even if the size of the RB acting as interference is increased by configuring aggregated time slots, the adverse effect on the data transmission throughput is small. On the contrary, the number of time slots acting as interference is reduced, and therefore the total amount of interference is reduced, thereby improving the performance of data transmission.

[0107] Fig. 9 A flow chart 900 between a cell and an aggregated time slot management device according to various embodiments of the present disclosure is shown.

[0108] Reference Fig. 9 , the aggregation timeslot management device 920 may configure a specific timeslot in the time domain for aggregating traffic of the cell to control inter-cell interference (935). The specific timeslot in the time domain may be referred to as an interference aggregation timeslot or an aggregation timeslot. When an aggregation timeslot is configured, traffic sent within a predetermined interval may be aggregated and allocated to the aggregation timeslot.

[0109] The aggregated time slot management device 920 may be an entity on the network, may be an independent device, or may correspond to a part of the function of another network entity.

[0110] The aggregation time slot management device may pre-configure the aggregation time slot. Specifically, the positions of the aggregation time slots of the cells managed by the aggregation time slot management device may be aligned identically. In addition, the aggregation time slots for each cell may include the same operation interval and offset configuration.

[0111] According to an embodiment of the present disclosure, the radio resources to which the cell traffic is allocated may be aggregated into a preconfigured aggregation time slot and scheduled.

[0112] The aggregated time slot management device 920 may transmit information (940) about the aggregated time slots configured for the serving cell 910 and the interfering cell 930 connected to the aggregated time slot management device 920. The serving cell 910 may refer to a serving base station that transmits data to the UE, and the interfering cell 930 may refer to a cell of an interfering base station that is adjacent to the serving base station and may cause inter-cell interference in data transmission from the serving cell to the UE.

[0113] According to an embodiment of the present disclosure, the aggregation time slot management device may transmit information on the aggregation time slot having the same position for each of the plurality of cells managed by the aggregation time slot management device.

[0114] The serving cell 910 may aggregate and allocate traffic to be transmitted within a predetermined interval to the aggregated time slot based on the information about the aggregated time slot received from the aggregated time slot management device 920 (945). When the traffic allocated to the aggregated time slot exceeds the allocated wireless resources, the serving cell may allocate the excess traffic to the next time slot of the aggregated time slot. According to an embodiment of the present disclosure, even when the next time slot of the aggregated time slot is a non-aggregated time slot, because most of the traffic acting as interference to the wireless resources of the serving cell may have been transmitted in the aggregated time slot, the influence of the excess traffic allocated to the non-aggregated time slot on the serving cell can be minimized.

[0115] According to an embodiment of the present disclosure, the serving cell may receive information about the aggregated time slots of multiple neighboring cells from the aggregated time slot management device. The serving cell may schedule traffic in the same aggregated time slot as the aggregated time slot of the multiple neighboring cells based on the information about the aggregated time slots of the multiple neighboring cells. In this case, the aggregated time slots of the multiple neighboring cells may be aggregated time slots having the same position for each neighboring cell.

[0116] Thereafter, the serving cell 910 may determine separate AMCs for the aggregated time slots and the non-aggregated time slots based on the information about the aggregated time slots (950). According to an embodiment of the present disclosure, if the past transmission in the aggregated time slot is ACK, the SINR of the aggregated time slot may be increased, and if the past transmission in the aggregated time slot is NACK, the SINR may be decreased. If the past transmission in the non-aggregated time slot is ACK, the SINR of the non-aggregated time slot may be increased, and if the past transmission in the non-aggregated time slot is NACK, the SINR may be decreased. By increasing the strength of the received signal of the uplink, the SINR may be increased.

[0117] An adaptive modulation and coding selection (MCS) level is selected based on the signal SINR ratio of the channel for transmitting and receiving data. A low MCS level is applied to aggregated time slots and a high MCS level is applied to non-aggregated time slots, so that a low data transmission rate can be applied to aggregated time slots where the frequency of inter-cell interference is expected to be high.

[0118] Finally, the serving cell 910 may transmit traffic of the aggregated time slot to the UE using the separately determined AMC (955). In this case, the probability of occurrence of inter-cell interference of traffic transmitted to the UE may be lower than the probability of occurrence of inter-cell interference of traffic when the aggregated time slot is not configured.

[0119] According to an embodiment of the present disclosure, the serving cell may send traffic of the same aggregated time slot as the aggregated time slots of multiple neighboring cells to the UE. In this case, the aggregated time slots of multiple neighboring cells may be aggregated time slots having the same position for each neighboring cell.

[0120] The interfering cell 930 can aggregate and allocate the traffic to be sent within a predetermined interval to the aggregated time slot (960) based on the information about the aggregated time slot received from the aggregated time slot management device 920. The transmission can be delayed (delayed) until the traffic of the cell that can act as interference arrives at the aggregated time slot. Therefore, the traffic of the cell that can act as interference can be aggregated in the aggregated time slot, and the number of time slots occupied by the traffic of the cell can be reduced compared to the number of time slots occupied by the traffic of the cell before configuring the aggregated time slot. In other words, the number of time slots that act as interference is reduced, and therefore the total amount of interference is reduced, thereby improving the performance of data transmission.

[0121] The interfering cell 930 may transmit the traffic of the neighboring cells to the UE, which is aggregated in the aggregation time slot and acts as interference (965).

[0122] Fig.10 Operations 1000 of a serving base station according to various embodiments of the present disclosure are shown. A serving cell 910 may refer to a serving base station that transmits data to a UE.

[0123] refer to Fig.10 In operation 1010, the serving cell may receive information about the aggregated time slot from an aggregated time slot management device connected to the serving cell. The information about the aggregated time slot may include information that specific time slots at predetermined intervals are configured as time slots for aggregating and allocating cell traffic.

[0124] In operation 1020, the serving cell may aggregate traffic to be transmitted within a predetermined interval into the aggregation timeslot based on the information about the aggregation timeslot, and schedule the aggregated traffic.

[0125] According to an embodiment of the present disclosure, when the traffic allocated to the aggregated time slot exceeds the allocated wireless resources, the serving cell may allocate the excess traffic to the next time slot of the aggregated time slot. In this case, the excess traffic may be allocated even when the next time slot of the aggregated time slot is a non-aggregated time slot.

[0126] In operation 1030, the serving cell may determine separate AMCs for the aggregated time slots and the non-aggregated time slots. According to an embodiment of the present disclosure, if the past transmission in the aggregated time slot is ACK, the SINR of the aggregated time slot may be increased, and if the past transmission in the aggregated time slot is NACK, the SINR may be reduced. If the past transmission in the non-aggregated time slot is ACK, the SINR of the non-aggregated time slot may be increased, and if the past transmission in the non-aggregated time slot is NACK, the SINR may be reduced. By increasing the strength of the received signal of the uplink, the SINR may be increased.

[0127] That is, a low MCS level is applied to aggregated timeslots and a high MCS level is applied to non-aggregated timeslots, so that a lower data transmission rate can be applied to aggregated timeslots in which the frequency of occurrence of inter-cell interference is expected to be high.

[0128] In operation 1040, the serving cell may transmit traffic of the aggregated timeslot to the UE by using the separately determined AMC. In this case, the probability of occurrence of inter-cell interference of traffic transmitted to the UE may be lower than the probability of occurrence of inter-cell interference of traffic when the aggregated timeslot is not configured.

[0129] Fig.11 1100 shows the operation of a neighboring base station according to various embodiments of the present disclosure. A neighboring cell may refer to a cell of a neighboring base station that is adjacent to a serving base station and may cause inter-cell interference in data transmission from the serving cell to a UE. A neighboring cell may be referred to as an interfering cell (e.g., Fig. 9 of 930).

[0130] refer to Fig.11 In operation 1110, the neighboring cell may receive information about the aggregated time slot from an aggregated time slot management device connected to the neighboring cell. The information about the aggregated time slot may include information that specific time slots at predetermined intervals are configured as time slots for aggregating and allocating cell traffic.

[0131] In operation 1120, the neighboring cell may aggregate the traffic that acts as interference to be transmitted at a predetermined interval into the aggregated time slot based on the information about the aggregated time slot received from the aggregated time slot management device, and schedule the aggregated traffic. The transmission may be delayed (delayed) until the traffic that acts as interference arrives at the aggregated time slot. Therefore, the traffic of the neighboring cell that acts as interference may be aggregated into the aggregated time slot, and the number of time slots occupied by the traffic of the neighboring cell that acts as interference may be reduced compared to the number of time slots occupied by the traffic of the neighboring cell that acts as interference when the aggregated time slot is not configured.

[0132] In operation 1130, the neighboring cell may transmit traffic of the aggregated time slot to the UE.

[0133] Fig.12A graph of time slot usage versus period of aggregated time slots according to various embodiments of the present disclosure is shown. Specifically, simulation results based on traffic patterns collected from a commercial network are shown.

[0134] refer to Fig.12 , the horizontal axis may represent the time domain, and specifically, represent the period of the aggregated time slot configured by the TDIA operation, which is an operation of configuring the aggregated time slot to control the inter-cell interference in the time domain. The vertical axis may represent the time slot utilization rate, and the time slot utilization rate may refer to the ratio of the time slots used to send traffic among all time slots. When the time slot utilization rate is high, in addition to the traffic expected to be sent by the serving cell, there is a high probability that there is also a time slot allocated with the traffic of the neighboring cell acting as interference. That is, the time slot utilization rate may indicate the possibility of potential inter-cell interference.

[0135] exist Fig.12 In , when traffic is sent without configuring aggregated time slots (in the case of TDIA being off), the time slot usage rate may indicate a value of 22.7%. This may indicate that the probability of occurrence of potential inter-cell interference is 22.7%. Fig.12 In the example, when traffic is sent by configuring aggregated time slots (with TDIA turned on), the time slot utilization rate may be lower than the value of 22.7% as the operation interval of the aggregated time slot increases. For example, when the operation interval of the aggregated time slot is configured as 10 time slots, the time slot utilization rate can be reduced to 15.2%. This can indicate that the probability of occurrence of potential inter-cell interference has been reduced to 15.2%. That is, if the sending of traffic is delayed by up to 10 time slots and the traffic is aggregated and distributed, the probability of occurrence of inter-cell interference can be reduced from 22.7% to 15.2%, a total reduction of 33%.

[0136] In addition, as the number of time slots constituting the operation interval of the aggregated time slot increases, the time slot usage rate may gradually decrease and then converge to a predetermined value. Fig.12 In the example, when the operation interval of the aggregated slot is configured as 10 slots, the slot utilization rate is 15.2%, and when the operation interval of the aggregated slot is configured as 30 slots, the slot utilization rate is 12.0%. As the operation interval of the aggregated slot increases, the slot utilization rate can gradually decrease and then converge to a value of 10.4%.

[0137] Fig.13 A graph showing time slot usage versus period of aggregated time slots according to various embodiments of the present disclosure is shown.

[0138] Reference Fig.13, the horizontal axis represents the time domain, specifically, represents the time slot index when the operation interval of the aggregated time slot is configured as 10 time slots. The vertical axis may represent the time slot utilization rate, and the time slot utilization rate may refer to the ratio of the time slots used to send traffic in all time slots. When the time slot utilization rate is high, in addition to the traffic expected to be sent by the serving cell, there is a high probability that there is also a time slot allocated with the traffic of the neighboring cell acting as interference. That is, the time slot utilization rate may indicate the possibility of potential inter-cell interference.

[0139] exist Fig.13 In the example, when traffic is sent without configuring aggregated time slots in the downlink (DL) (when TDIA is turned off), the average value of the time slot utilization rate can indicate a value of 22.7%. When aggregated time slots are configured and traffic is sent (when TDIA is turned on), the average value of the time slot utilization rate can indicate a value of 15.2%. That is, it can be seen that when aggregated time slots are configured and traffic from neighboring cells acting as interference is aggregated and distributed, the average value of the time slot utilization rate is reduced from 22.7% to 15.2%, compared to when aggregated time slots are not configured. This can indicate that the probability of occurrence of potential inter-cell interference has been reduced from 22.7% to 15.2%.

[0140] In addition, when checking the pattern of the figure, in the case of sending traffic without configuring the aggregate time slot, the traffic causing interference is evenly distributed in each time slot, and thus the time slot usage rate can be evenly distributed in all time slots. On the other hand, in the case of sending traffic by configuring the aggregate time slot, the traffic causing interference is aggregated in and around the aggregate time slot, and thus the time slot usage rate in the aggregate time slot can be high.

[0141] Fig.14 A graph of data throughput versus signal-to-noise ratio (SNR) is shown according to various embodiments of the present disclosure.

[0142] Reference Fig.14 , the horizontal axis of the graph represents SNR, and the vertical axis represents throughput of DL data. When data is processed without configuring a regular aggregated time slot, the data throughput relative to the signal-to-noise ratio may be lower than when an aggregated time slot is configured and data is processed.

[0143] Furthermore, even in the case where traffic is sent by configuring an aggregated timeslot, data throughput may be higher in the case where traffic is aggregated and allocated to the aggregated timeslot and separate AMCs are determined for the aggregated timeslot and non-aggregated timeslots other than the aggregated timeslot, rather than aggregating and allocating traffic to the aggregated timeslot.

[0144] That is, it can be appreciated that the case of processing data by aggregating and allocating traffic of neighboring cells acting as interference to the aggregated time slot shows higher data throughput than the case of not configuring the aggregated time slot to process data. This can indicate that the case of configuring the aggregated time slot can improve the performance of data processing. For example, in Fig.14 In the study, when aggregated timeslots are configured and separate AMCs are determined for aggregated timeslots and non-aggregated timeslots (with TDIA turned on), the data throughput is improved by 5% to 36% compared to the data throughput when aggregated timeslots are not configured (with TDIA turned off). On average, the data throughput can be improved by 17%.

[0145] Fig.15 The structure of a base station according to various embodiments of the present disclosure is shown.

[0146] Reference Fig.15 , the base station 1500 includes a communication unit 1510 , a storage device 1520 and a controller 1530 .

[0147] The communication unit 1510 performs the function of sending / receiving signals through a wireless channel. For example, the communication unit 1510 performs the conversion function between the baseband signal and the bit string according to the physical layer specification of the system. For example, during data transmission, the communication unit 1510 encodes and modulates the transmitted bit string to generate a composite symbol. In addition, during data reception, the communication unit 1510 demodulates and decodes the baseband signal to recover the received bit string. In addition, the wireless communication unit 1510 up-converts the baseband signal to an RF band signal, transmits it through an antenna, and down-converts the RF band signal received through the antenna to a baseband signal.

[0148] To this end, the wireless communication unit 1510 may include a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a digital-to-analog converter (DAC), an analog-to-digital converter (ADC), etc. In addition, the communication unit 1510 may include multiple transmission / reception paths. In addition, the wireless communication unit 1510 may include at least one antenna array including multiple antenna elements. In terms of hardware, the wireless communication unit 1510 may include a digital unit and an analog unit, and the analog unit may include multiple subunits according to operating power, frequency, etc.

[0149] The communication unit 1510 may transmit / receive signals. To this end, the communication unit 1510 may include at least one transceiver. For example, the communication unit 1510 may transmit synchronization signals, reference signals, system information, messages, control information, data, etc. In addition, the communication unit 1510 may perform beamforming.

[0150] The communication unit 1510 transmits and receives signals as described above. Therefore, all or part of the communication unit 1510 may be referred to as a "transmitter," "receiver," or "transceiver." In addition, as used in the following description, the meaning of "transmission and reception performed through a wireless channel" includes the meaning of the communication unit 1510 performing the above-mentioned processing.

[0151] The storage device 1520 stores data such as basic programs, application programs, and configuration information for base station operation. The storage device 1520 may include a memory. The storage device 1520 may include a volatile memory, a nonvolatile memory, or a combination of a volatile memory and a nonvolatile memory. In addition, the storage unit 1520 provides the stored data at the request of the controller 1530.

[0152] The controller 1530 controls the overall operation of the base station 1500. For example, the controller 1530 sends / receives a signal through the communication unit 1510. In addition, the controller 1530 records data in the memory 1520 and reads data from the storage device 1520. In addition, the controller 1530 may perform the functions of the protocol stack required by the communication specification. To this end, the controller 1530 may include at least one processor.

[0153] Fig.15 The structure of the base station 1500 shown in FIG. 1 is merely an example of a base station, and examples of base stations for performing various embodiments of the present disclosure are not limited to Fig.15 That is, according to various embodiments, some elements may be added, omitted or changed.

[0154] exist Fig.15 In the present disclosure, the base station 1500 is described as a single entity, but the present disclosure is not limited thereto. In addition to the integrated deployment, the base station 1500 according to various embodiments of the present disclosure may be implemented to build an access network with a distributed deployment. According to an embodiment, the base station may be divided into a central unit (CU) and a digital unit (DU), the CU may be implemented to perform upper layer functions (e.g., packet data convergence protocol (PDCP) and RRC), and the DU may be implemented to perform lower layer functions (e.g., media access control (MAC) and physical (PHY)). The DU of the base station may form beam coverage on a wireless channel.

[0155] The embodiments of the present disclosure are only specific examples proposed to easily explain the technical content of the embodiments of the present disclosure and help understand the various embodiments of the present disclosure, and are not intended to limit the scope of the embodiments of the present disclosure. That is, it will be understood by those skilled in the art that other variations based on the technical ideas of the present disclosure can be realized. In addition, the above-mentioned various embodiments can be used in combination as needed.

[0156] As described above, according to various embodiments of the present disclosure, a method performed by a service cell in a wireless communication system may include receiving information about aggregated time slots from an aggregated time slot management device, aggregating traffic to be sent during a predetermined interval into aggregated time slots based on the information about the aggregated time slots and scheduling the aggregated traffic, determining separate adaptive modulation and coding (AMC) for aggregated time slots and non-aggregated time slots, and sending the traffic of the aggregated time slots to the terminal by using the determined AMC.

[0157] According to various embodiments of the present disclosure, the method may include allocating excess traffic to a next time slot of the aggregated time slot when the traffic allocated to the aggregated time slot exceeds the allocated radio resources.

[0158] According to various embodiments of the present disclosure, the aggregated time slots may be aligned to the same position in all cells of a base station managed by an aggregated time slot management device.

[0159] According to various embodiments of the present disclosure, the aggregated time slot may be repeatedly configured according to a preconfigured period.

[0160] According to various embodiments of the present disclosure, determining the AMC may further include applying a low modulation coding schedule (MCS) level to the aggregated time slots and applying a high MCS level to the non-aggregated time slots.

[0161] As described above, according to various embodiments of the present disclosure, a device of a serving cell in a wireless communication system may include a transceiver and at least one processor, wherein the at least one processor is configured to receive information about aggregated time slots from an aggregated time slot management device, aggregate traffic to be sent during a predetermined interval into aggregated time slots based on the information about the aggregated time slots, schedule the aggregated traffic, determine separate adaptive modulation and coding (AMC) for aggregated time slots and non-aggregated time slots, and send the traffic of the aggregated time slots by using the determined AMC.

[0162] According to various embodiments of the present disclosure, the at least one processor may be configured to allocate excess traffic to a next time slot of the aggregated time slot when the traffic allocated to the aggregated time slot exceeds the allocated radio resources.

[0163] According to various embodiments of the present disclosure, the aggregated time slots may be aligned to the same position in all cells of a base station managed by an aggregated time slot management device.

[0164] According to various embodiments of the present disclosure, the aggregated time slot may be repeatedly configured according to a preconfigured period.

[0165] According to various embodiments of the present disclosure, at least one processor may be configured to apply a low modulation coding schedule (MCS) level to aggregated time slots and a high MCS level to non-aggregated time slots.

[0166] As described above, according to various embodiments of the present disclosure, the method performed by an interfering cell in a wireless communication system may include receiving information about an aggregated time slot from an aggregated time slot management device, aggregating traffic to be sent during a predetermined interval into an aggregated time slot based on the information on the aggregated time slot, scheduling the aggregated traffic, and sending traffic in the aggregated time slot.

[0167] According to various embodiments of the present disclosure, aggregating traffic into an aggregated time slot and allocating the aggregated traffic may include waiting until the traffic is allocated to a most adjacent aggregated time slot after a time slot in which the traffic has occurred among the time slots.

[0168] According to various embodiments of the present disclosure, the aggregated time slots may be aligned to the same position in all cells of a base station managed by an aggregated time slot management device.

[0169] According to various embodiments of the present disclosure, the aggregated time slot may be repeatedly configured according to a preconfigured period.

[0170] As described above, according to various embodiments of the present disclosure, a device of an interfering cell in a wireless communication system may include a transceiver and at least one processor, wherein the at least one processor is configured to receive information about an aggregated time slot from an aggregated time slot management device, aggregate traffic to be sent during a predetermined interval into an aggregated time slot based on the information about the aggregated time slot, schedule the aggregated traffic, and send the traffic in the aggregated time slot.

[0171] According to various embodiments of the present disclosure, the at least one processor may be configured to aggregate traffic and allocate it to aggregated time slots, and wait until the traffic is allocated to the most adjacent aggregated time slot after the time slot at which the traffic has arrived in the time slots.

[0172] According to various embodiments of the present disclosure, the aggregated time slots may be aligned to the same position in all cells of a base station managed by an aggregated time slot management device.

[0173] According to various embodiments of the present disclosure, the aggregated time slot may be repeatedly configured according to a preconfigured period.

Claims

1. A method performed by a serving base station in a wireless communication system, the method include: receiving information about aggregated time slots from an aggregated time slot management device; scheduling traffic by aggregating traffic to be sent during a predetermined interval into the aggregated time slot based on the information about the aggregated time slot; Determine separate adaptive modulation and coding (AMC) for the aggregated time slots and the non-aggregated time slots; as well as The traffic of the aggregated timeslot is sent to the terminal using the determined AMC.

2. The method according to claim 1, in, The method includes allocating excess traffic to a next time slot of the aggregated time slot when the traffic allocated to the aggregated time slot exceeds the allocated radio resources.

3. The method according to claim 1, in, The aggregated time slot is aligned to the same position in all cells of the base station managed by the aggregated time slot management device, and is repeatedly configured according to a preconfigured period.

4. The method according to claim 1, in, Determining the AMC further comprises: Applying a low modulation coding schedule (MCS) level to the aggregated time slot; and A high MCS level is applied to the non-aggregated timeslots.

5. A device for a serving base station in a wireless communication system, the device include: Transceiver; as well as at least one processor, Wherein, the at least one processor is configured to: receiving information about aggregated time slots from an aggregated time slot management device; Based on the information about the aggregated time slot, aggregating the traffic to be sent during the predetermined interval into the aggregated time slot and scheduling the aggregated traffic; Determining separate adaptive modulation and coding (AMC) for the aggregated time slots and the non-aggregated time slots; and The traffic of the aggregated timeslot is sent to the terminal using the determined AMC.

6. The device according to claim 5, in, The at least one processor is configured to allocate excess traffic to a next time slot of the aggregated time slot when the traffic allocated to the aggregated time slot exceeds the allocated radio resources.

7. The device according to claim 5, in, The aggregated time slot is aligned to the same position in all cells of the base station managed by the aggregated time slot management device, and is repeatedly configured according to a preconfigured period.

8. The device according to claim 5, in, The at least one processor is configured to: Applying a low modulation coding schedule (MCS) level to the aggregated time slot; and A high MCS level is applied to the non-aggregated timeslots.

9. A method performed by a neighboring base station in a wireless communication system, the method include: receiving information about aggregated time slots from an aggregated time slot management device; Based on the information about the aggregated time slot, aggregating the traffic to be sent during the predetermined interval into the aggregated time slot and scheduling the aggregated traffic; as well as The traffic of the aggregated timeslot is sent to the terminal.

10. The method according to claim 9, in, Aggregating the traffic into the aggregated time slot and scheduling the aggregated traffic includes waiting until the traffic is scheduled into the most adjacent aggregated time slot after the time slot in which the traffic has occurred.

11. The method according to claim 9, in, The aggregated timeslot is aligned to the same position in all cells of the base station managed by the aggregated timeslot management device.

12. The method according to claim 9, in, The aggregated time slot is repeatedly configured according to a preconfigured period.

13. A device adjacent to a base station in a wireless communication system, the device include: Transceiver; as well as at least one processor, Wherein, the at least one processor is configured to: receiving information about aggregated time slots from an aggregated time slot management device; Based on the information about the aggregated time slot, aggregating the traffic to be sent during the predetermined interval into the aggregated time slot and scheduling the aggregated traffic; as well as The traffic of the aggregated timeslot is sent to the terminal.

14. The device according to claim 13, in, The at least one processor is configured to: aggregating the traffic into the aggregated time slot and scheduling the aggregated traffic; as well as Wait until the flow is scheduled to the nearest aggregate time slot after the time slot in which the flow has occurred.

15. The device according to claim 13, in, The aggregated time slot is aligned to the same position in all cells of the base station managed by the aggregated time slot management device, and is repeatedly configured according to a preconfigured period.

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