Base station equipment, distributed unit and wireless unit, scheduling method

Abstract

To provide a method, a base station apparatus, a distributed unit (DU) and a radio unit (RU) which are able to avoid inter-cell interference, and a scheduling method practiced in each of the base station apparatus and the DU.SOLUTION: A base station schedules traffic (downlink / uplink) in units of groups in each cell, and determines and schedules the allocation order of resources (sub-frames, slots, RBs) in a group to be different for each cell, so that inter-cell scheduling occupancy is distributed.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a technique for avoiding inter-cell interference.

[0002] This application claims the priority of Korean Application No. 10-2023-0075633, filed on June 13, 2023, and the entire contents of such application are incorporated herein by reference for all purposes.

Background Art

[0003] 5G has a Lean-carrier Design, and thus, the impact of interference on downlink / uplink performance appears more significantly compared to LTE where CRS (Cell-specific Reference Signal) is always transmitted.

[0004] The biggest cause of interference is when the downlink signal transmitted by an adjacent cell affects the reception of the downlink signal of a terminal (UE) located in the serving cell, and when the uplink signal transmitted by a terminal (UE) located in an adjacent cell affects the UL reception of the serving cell, that is, the situation of inter-cell interference.

[0005] Therefore, research and development of techniques for minimizing inter-cell interference is one of the important issues.

[0006] The existing scheduling method of a base station is a method of sequentially allocating resources from the earliest available slot or sub-frame where downlink or uplink scheduling is possible when data transmitted from an upper layer arrives or when an uplink scheduling request is received from a terminal (UE).

[0007] While existing scheduling methods may appear efficient, they are not efficient in terms of inter-cell interference when adjacent cells are present.

[0008] In particular, in TDD systems, when following existing scheduling methods, the scheduling occupancy rate for the first downlink slot (or subframe) or the first uplink slot (or subframe) will be higher than that of other slots (or subframes).

[0009] As a result, when following the existing scheduling method, there is a problem where inter-cell interference frequently / significantly occurs in the first downlink slot (or subframe) or the first uplink slot (or subframe), where the scheduling occupancy rate is higher than that of other slots (or subframes).

[0010] This invention proposes a new technical solution that enables the distribution of scheduling occupancy, moving away from existing scheduling methods that have the characteristic of high scheduling occupancy at the same location (e.g., the first downlink / uplink slot) across cells. [Overview of the project] [Problems that the invention aims to solve]

[0011] The problem that this invention aims to solve is to move away from existing scheduling methods, which have the characteristic of high scheduling occupancy rates at the same location (e.g., the first downlink / uplink slot) across cells, and to realize a new technical solution that enables the distribution of scheduling occupancy rates. [Means for solving the problem]

[0012] A base station device according to one embodiment of the present invention includes: a memory containing instruction words; and a processor that, by executing the instruction words, allocates traffic to cells according to pre-configured groups of unit resources, and when allocating traffic according to the groups, determines that the allocation order of unit resources within each group is different in order to avoid inter-cell interference in the cells.

[0013] A distributed unit (DU) according to one embodiment of the present invention includes: a memory containing instruction words; and a processor that, by executing the instruction words, allocates traffic to cells according to pre-configured groups of unit resources, and when allocating traffic according to the groups, determines the allocation order of unit resources within the groups by inter-cell interference in the cells.

[0014] Specifically, when the processor allocates traffic by group, it can use the unit resource interference level measured for the cell to determine the allocation order of unit resources within the group.

[0015] Specifically, the processor can determine the interference level for each unit resource within a group, which is derived based on the interference level for each unit resource measured from the RU (Radio Unit) of the cell, and when allocating traffic to each group, it can determine the allocation order of the unit resources within the group based on the interference level for each unit resource within the group.

[0016] Specifically, the above processor can sequentially determine the allocation order based on the interference level of each unit resource within the above group, in order from the unit resource with the lowest interference level to the unit resource with the highest interference level.

[0017] Specifically, the above-mentioned unit resources may be a subframe, or each slot within a subframe, or each RB (Resource Block) within a slot.

[0018] A wireless unit (RU) that interacts with a distributed unit (DU) according to one embodiment of the present invention includes: a memory containing instruction words; and a processor that, by executing the instruction words, measures the interference level for each unit resource and transmits the information related to the measurement to the DU, so that when the DU allocates traffic to the cells of the RU according to pre-configured groups of unit resources, it can use the transmitted information to determine the allocation order of the unit resources within the group.

[0019] Specifically, the information transmitted by the processor to the DU may be information measuring the interference level for each individual resource, or information calculating the interference level for each individual resource within the group using the measured interference level for each individual resource.

[0020] A scheduling method performed by a base station device according to one embodiment of the present invention includes the step of allocating traffic to a cell in groups of pre-configured unit resources; in the step of allocating traffic in groups, the allocation order of unit resources within each group can be determined to be different in order to avoid inter-cell interference in the cell.

[0021] A scheduling method performed in a distributed unit (DU) according to a fifth aspect of the present invention to achieve the above objectives includes the step of allocating traffic to a cell in groups of pre-configured unit resources; the step of allocating traffic in groups determines the allocation order of unit resources within a group by inter-cell interference in the cell.

[0022] Specifically, when allocating traffic to the above groups, the above steps can determine the allocation order of unit resources within a group by utilizing the unit resource interference level measured for the above cells. [Effects of the Invention]

[0023] According to an embodiment of the present invention, traffic (downlink / uplink) is scheduled in each cell in group units, and a specific technical configuration is realized in which the allocation order of resources (subframes, slots, RBs) within a group is determined and scheduled differently for each cell.

[0024] Thereby, according to the present invention, it is possible to deviate from the existing scheduling method in which the scheduling occupancy rate is high at the same position (e.g., the first downlink / uplink slot) among cells, and it is possible to disperse the scheduling occupancy rate among cells, thus avoiding inter-cell interference and deriving an effect of improving downlink / uplink transmission performance.

Brief Description of Drawings

[0025] [Figure 1] It is an exemplary diagram showing the situation of inter-cell interference. [Figure 2] It is a drawing showing the configurations of DU and RU according to an embodiment of the present invention. [Figure 3] It is an exemplary diagram showing a configuration example of a group of unit resources (e.g., slots) presented in the present invention. [Figure 4A] It is a drawing showing an embodiment in which scheduling is performed using the interference level for each unit resource (e.g., slot) within a group in the present invention. [Figure 4B] It is a drawing showing an embodiment in which scheduling is performed using the interference level for each unit resource (e.g., slot) within a group in the present invention. [Figure 5] It is a drawing showing an example of determining the allocation order using the interference level for each unit resource (e.g., slot) within a group in the present invention. [Figure 6] It is an exemplary diagram showing the effect of avoiding inter-cell interference obtained by applying the present invention. [Figure 7] It is a drawing showing an embodiment in which the unit resource is applied as an RB in the present invention. [Figure 8] It is a drawing showing an embodiment in which cell information (e.g., PCI) or a third external device is used in the present invention. [Figure 9A] This drawing shows an embodiment in which cell information (e.g., PCI) or a third external device is used in the present invention. [Figure 9B] This drawing shows an embodiment in which cell information (e.g., PCI) or a third external device is used in the present invention. [Modes for carrying out the invention]

[0026] Various embodiments of the present invention will be described below with reference to the attached drawings.

[0027] This invention relates to a technique for avoiding inter-cell interference.

[0028] 5G utilizes a Lean-carrier design, which means that, compared to LTE where the CRS (Cell-specific Reference Signal) is always transmitted, interference has a greater impact on downlink / uplink performance.

[0029] The primary cause of interference is inter-cell interference, which occurs when downlink signals transmitted by adjacent cells affect the reception of downlink signals by terminals (UEs) located in a serving cell, or when uplink signals transmitted by adjacent cells affect the reception of uplink signals by the serving cell.

[0030] Figure 1 illustrates this inter-cell interference situation.

[0031] As can be seen from Figure 1, in the case of downlink, a downlink interference situation can occur where the DL signal to UE#2 acts as interference to UE#1.

[0032] In the case of uplinks, uplink interference can occur where the UL signal of UE#1 interferes with the reception of the UL signal of UE#2.

[0033] Therefore, one of the important challenges is the research and development of techniques to minimize such inter-cell interference.

[0034] On the other hand, the base station scheduling method is to allocate resources sequentially from the earliest available slot or subframe for downlink or uplink scheduling when data is received from a higher layer or when an uplink scheduling request is received from a terminal (UE).

[0035] While existing scheduling methods may appear efficient, they are not efficient in terms of inter-cell interference when adjacent cells are present.

[0036] In particular, in TDD systems, when following existing scheduling methods, the scheduling occupancy rate for the first downlink slot (or subframe) or the first uplink slot (or subframe) will be higher than that of other slots (or subframes).

[0037] This is because downlink data cannot be transmitted while uplink transmission is in progress. Therefore, data transmitted from higher layers is buffered before being transmitted from the first approaching DL scheduling location (i.e., the first downlink slot (or subframe)) (the same applies to UL scheduling).

[0038] As a result, when following the existing scheduling method, there is a problem where inter-cell interference frequently / significantly occurs in the first downlink slot (or subframe) or the first uplink slot (or subframe), where the scheduling occupancy rate is higher than that of other slots (or subframes).

[0039] This invention aims to break away from existing scheduling methods, which are characterized by high scheduling occupancy rates at the same location (e.g., the first downlink / uplink slot) across cells, and to realize a new technical solution that enables the distribution of scheduling occupancy rates.

[0040] More specifically, this aims to realize a new technical approach (scheduling technique) that enables the distribution of scheduling occupancy by scheduling traffic (downlink / uplink) in groups within each cell, and determining and scheduling the allocation order of resources (subframes, slots, RBs) within each group differently for each cell.

[0041] In the following, with reference to Figure 2, we will specifically describe the configuration of the DU (Distributed Unit) and RU (Radio Unit) that realize the technical solution proposed in the present invention, namely, a new scheduling technique.

[0042] Before going into specifics, the present invention can be applied to existing 4G (LTE), 5G (NR), and future 6G technologies, and can be applied to all TDD (Time Division Duplex) and FDD (Frequency Division Duplex) systems, as well as to all existing RAN (Radio Access Network) and Open RAN (O-RAN) systems.

[0043] The core feature of this invention lies in realizing a technique that can minimize inter-cell interference by differentiating the order in which slots (or subframes) and / or RBs are assigned to each cell. It is also characterized by proposing an operation of the RU to effectively determine the assignment order.

[0044] For the sake of clarity, the following description will explain the features and various embodiments of the present invention based on the 5G(NR) standard.

[0045] Figure 2 shows the configurations of the distributed unit 10 (hereinafter referred to as DU10) and the wireless unit 20 (hereinafter referred to as RU20) according to an embodiment of the present invention.

[0046] The base station equipment may be configured to include such DU10 and RU20.

[0047] Therefore, a base station device to which the present invention is applied may be configured to include a memory (not shown) containing instruction words, and a processor (corresponding to DU10 and / or RU20 in Figure 2) that, by executing the instruction words, allocates traffic to a cell in groups of unit resources set for that cell, and when allocating traffic to the groups, determines that the allocation order of the unit resources within the groups is different in order to avoid inter-cell interference in the cell.

[0048] The following describes in detail the configurations of DU10 and RU20 according to embodiments of the present invention.

[0049] First, with reference to Figure 2, an embodiment of the present invention, DU10, will be described.

[0050] An embodiment of the present invention may include a memory (not shown) containing instruction words, and a processor (hereinafter described as an allocation order determination unit 11 and a scheduling unit 12) that, by executing the instruction words, allocates traffic to cells in groups of pre-configured unit resources, and determines the allocation order of unit resources within a group based on inter-cell interference in the cell when allocating traffic to the groups.

[0051] More specifically, DU10 can allocate traffic to each cell (e.g., Cell1, 2, ...) of each RU20 (e.g., RU1, 2, ...) that it interacts with, according to pre-configured groups of unit resources.

[0052] Here, a unit resource can be a subframe, or each slot within a subframe, or each RB (Resource Block) within a slot.

[0053] In other words, the scheduling unit 12 configured in the DU10 of the present invention can allocate traffic to each cell (e.g., Cell1, 2, ...) that is linked with the DU10, according to groups of subframes, slots, or RBs.

[0054] However, for the sake of clarity, the following explanation will assume that a unit resource is a slot, and will describe an example in which traffic is allocated to groups of slots.

[0055] In other words, the scheduling unit 12 configured in DU10 can allocate DL / UL traffic to each cell (e.g., Cell1, 2, ...) that is linked to DU10 in units of slot groups.

[0056] Therefore, according to the present invention, during traffic transmission to the Nth group, traffic that will be transmitted from the N+1th group can be collected and buffered.

[0057] The group of slots presented in this invention can be configured as follows: • FDD system: Grouping based on the number of consecutive slots set in advance (DL / UL can be set individually). • TDD system: 1) Group consecutive slots of the same type. 2) Grouping based on the number of consecutive slots set in advance (DL / UL can be set individually)

[0058] In this regard, Figure 3 shows an example configuration related to the group presented in the present invention.

[0059] Referring to Figure 3, the diagram illustrates an example where, in the case of an FDD system, four DL slots and three UL slots are configured as a single group (Set#1,#2,#3,...).

[0060] In the case of a TDD system, the diagram illustrates examples related to the above-mentioned methods 1) and 2) for group formation.

[0061] The method described in 1) above is a method of bundling / composing consecutive slots of the same type into a single group (Set) (Case #1).

[0062] On the other hand, method 2) described above is a method in which consecutive slots are configured as a group (Set) based on a predetermined number of consecutive slots, similar to an FDD system (Case #2). Figure 3 illustrates an example in which 8 DLs and 6 ULs of consecutive slots are bundled / configured as a group (Set).

[0063] As can be seen from Figure 3, the difference between a TDD system and an FDD system is that a TDD system has a mixture of DL and UL, and there can be spacing between slots within the bundle.

[0064] Therefore, a base station device to which the present invention is applied, in particular a DU10 within the base station device, can allocate / schedule DL / UL traffic to each cell (e.g., Cell1, 2, ...) that it interacts with, in the group units presented by the present invention.

[0065] Specifically, when DU10 allocates / schedules DL or UL traffic for the Nth group, it can buffer the data transmitted from the N+1th group.

[0066] Furthermore, once the transmission of the Nth group is complete, DU10 can allocate / schedule the previously buffered data, i.e., the DL or UL traffic of the N+1th group.

[0067] In particular, the present invention presents a method for allocating / scheduling DL / UL traffic on a slot (or subframe, or RB) group basis, as described above, in which the allocation order of slots (or subframes, or RBs) within a group is determined to be different in order to avoid inter-cell interference.

[0068] For this purpose, the allocation order determination unit 11 configured in the DU10 of the present invention performs the function of determining the allocation order of unit resources within a group, i.e., slots (or subframes, or RBs), by inter-cell interference in the cell, when allocating traffic by slot (or subframe, or RB) group as described above.

[0069] In the following explanation, as with the above-described embodiment, for the sake of explanation, we will refer to the unit resource as a slot and describe an embodiment in which the allocation order of slots within a group is determined.

[0070] To illustrate a specific embodiment, when the allocation order determination unit 11 allocates traffic to each cell (e.g., Cell1, 2, ...) that is linked with the DU10 in groups, it can determine the allocation order of slots within a group by utilizing the slot-specific interference level measured for each cell (e.g., Cell1, 2, ...).

[0071] Referring to Cell1, which is formed by RU1(20) among the cells (e.g., Cell1, 2, ...) shown in Figure 2, when the allocation order determination unit 11 allocates traffic to Cell1 in groups, it can determine the allocation order of slots within a group by utilizing the slot-specific interference level measured in Cell1.

[0072] More specifically, the allocation order determination unit 11 checks the slot-specific interference level within a group, which is derived based on the slot-specific interference level measured from the RU (hereinafter, RU1(20)) of the cell (hereinafter, Cell1). When allocating traffic by group, it can determine the allocation order of each slot within a group based on the confirmed slot-specific interference level within the group.

[0073] The following describes an example of a method for determining the allocation order of slots within a group.

[0074] In such embodiments, the method basically uses the slot-specific interference level measured / transmitted by the RU to determine the assignment order of each slot within the group.

[0075] More specifically, in the first embodiment, the RU (hereinafter, RU1(20)) can measure the interference level for each unit resource (e.g., slot) and transmit the measurement information to the DU10.

[0076] The "information" transmitted to DU10 at this time may be the information obtained by RU1(20) from measuring the interference level for each slot.

[0077] In other words, for example, RU1(20) can measure the slot-specific interference level in its own Cell1 and transmit such measurement information to DU10 periodically, when it senses a change in the surrounding environment, or at the request of DU10.

[0078] In this configuration, DU10 can use the slot-specific interference level measurement information transmitted from RU1(20) to calculate / derive the slot-specific interference level within a group by averaging the interference levels for each slot index within the group, based on the group configuration information for Cell1 of the corresponding RU1(20).

[0079] Therefore, the DU10 (allocation order determination unit 11) can sequentially determine the allocation order of slots within a group, starting from the unit resource (i.e., slot) with the lowest interference level, based on the slot-specific interference level within the group derived through the average calculation described above, and proceeding in order of increasing interference level.

[0080] On the other hand, to describe another second embodiment, in the present invention, the RU (hereinafter, RU1(20)) can measure the interference level for each unit resource (e.g., slot) and transmit the information related to the measurement to the DU10.

[0081] The "information" transmitted to DU10 at this time may be information obtained by RU1(20) after measuring the interference level for each slot, and then averaging the interference levels for each slot index within its own Cell1.

[0082] In other words, for example, RU1(20) may obtain and know the group configuration information related to its own Cell1 from DU10.

[0083] Furthermore, RU1(20) can measure the slot-specific interference level in its own Cell1 and calculate / derive the slot-specific interference level within the group by averaging the interference levels by slot index within the group based on the group configuration information related to its own Cell1.

[0084] Next, RU1(20) can periodically transmit to DU10 the slot-specific interference level information for Cell1, derived through measurement and averaging calculation as described above, either when sensing a change in the surrounding environment or at the request of DU10.

[0085] The DU10 (allocation order determination unit 11) can then sequentially determine the allocation order of slots within a group, starting from the lowest interference level (i.e., the slot) and proceeding in order of increasing interference level, based on the slot-specific interference levels within the group transmitted from the RU1 (20).

[0086] Therefore, when DU10 (scheduling unit 12) allocates / schedules DL / UL traffic to Cell1 in groups, it can allocate / schedule the DL / UL traffic in accordance with the allocation order of slots within the group determined by the allocation order determination unit 11.

[0087] On the other hand, in the second embodiment described above, more specifically, RU1(20) may directly determine the allocation order of slots within a group based on the slot-specific interference level related to Cell1 derived through measurement and averaging calculation, and transmit the determined allocation order to DU10 periodically, when a change in the surrounding environment is detected, or at the request of DU10.

[0088] In this case, when DU10 (scheduling unit 12) allocates / schedules DL / UL traffic to Cell1 in groups, it can allocate / schedule the DL / UL traffic according to the slot allocation order within the group transmitted from RU1 (20).

[0089] Therefore, in the present invention, when DU10 allocates / schedules DL or UL traffic of the Nth group to each cell (e.g., Cell1, 2, ...), it buffers the data to be transmitted from the N+1th group, and once the transmission of the Nth group is complete, it can allocate / schedule the previously buffered data, i.e., the DL or UL traffic of the N+1th group, to the cell in accordance with the allocation order of slots within the group determined.

[0090] Next, an embodiment of the present invention, RU20, will be described with reference to Figure 2.

[0091] An embodiment of the present invention may include a memory (not shown) containing instruction words, and a processor (hereinafter described as interference level measurement unit 21 and information transmission unit 22) that, by executing the instruction words, measures the interference level for each unit resource, transmits the information related to the measurement to the DU10, and causes the DU10 to allocate traffic to the cells of the RU20 according to pre-set groups of unit resources, and when allocating traffic according to the groups, uses the information to determine the allocation order of unit resources within the group.

[0092] In the following explanation, for the sake of clarity, we will refer to the unit resource as a slot and assume an example in which traffic is allocated to groups of slots.

[0093] The interference level measurement unit 21 can measure the interference level for each slot in the cells of RU20.

[0094] The information transmission unit 22 can transmit relevant information regarding the slot-specific interference level measured by the interference level measurement unit 21 to the DU 10 periodically, when it detects a change in the surrounding environment, or at the request of the DU 10.

[0095] In this case, as in the first embodiment described above, the "information" transmitted to DU10 may be information obtained by RU20 (interference level measurement unit 21) from measuring the interference level for each slot.

[0096] In this first embodiment, DU10 can use the slot-specific interference level measurement information transmitted from RU20 to calculate / derive the slot-specific interference level within a group by averaging the interference levels for each slot index within the group based on the group configuration information for the cell of the RU20 in question.

[0097] Therefore, DU10 can sequentially determine the allocation order of slots within a group for the cells of RU20, based on the slot-specific interference levels within the group derived through the average calculation described above, in order from the lowest interference level (i.e., the lowest interference level) to the highest interference level.

[0098] On the other hand, as in the second embodiment described above, the "information" transmitted to DU10 may be information obtained by RU20 measuring the interference level for each slot index within its own cell and then averaging those interference levels for each slot index within the group.

[0099] In this second embodiment, DU10 can sequentially determine the allocation order of slots within a group to the cells of RU20, based on the slot-by-slot interference levels within the group transmitted from RU20, in order from the lowest interference level (i.e., the lowest) to the highest interference level.

[0100] Therefore, in the present invention, when DU10 allocates / schedules DL or UL traffic of the Nth group to each cell (e.g., Cell1, 2, ...), it buffers the data to be transmitted from the N+1th group, and once the transmission of the Nth group is complete, it can allocate / schedule the previously buffered data, i.e., the DL or UL traffic of the N+1th group, to the cell in accordance with the allocation order of slots within the group determined.

[0101] Figures 4A and 4B are diagrams illustrating an embodiment of the present invention in which scheduling is performed using the interference level of individual unit resources (e.g., slots) within a group.

[0102] Case #1, shown in Figure 4A, is an embodiment in which DU10 determines the allocation order of slots within a group, and corresponds to the first embodiment described above.

[0103] To explain, 1. RU20 measures the interference level for each slot and 2. transmits it to DU10. 3. DU10 processes the transmitted slot interference levels (e.g., average calculation) according to the group configuration information for the cells of RU20, and 4. determines the assignment order of slots within the group.

[0104] On the other hand, Case #2, shown in Figure 4B, is an embodiment in which RU20 determines the allocation order of slots within a group, and corresponds to the second embodiment described above.

[0105] To explain, 1. DU10 transmits group configuration information to RU20 in advance, 2. RU20 measures the interference level for each slot, 3. RU20 processes the measured interference levels for each slot (e.g., by averaging) to determine the allocation order of slots within the group, and 4. RU20 can then transmit the determined allocation order of slots within the group to DU10.

[0106] Figure 5 shows an example of allocation order determination using the interference level of individual resources (e.g., slots) within a group, according to the present invention.

[0107] In other words, the first and second embodiments described above illustrate, as an example, how the slot assignment order is determined by the interference level of the slots within the group.

[0108] Figure 5 shows an example where five slots are configured as a single group for the DL.

[0109] Therefore, as shown in Figure 5, based on the slot-specific interference levels within a group derived through processing of slot-specific interference levels (e.g., average calculation), assignment order 1 can be determined for the slot with the lowest interference level (index 2), and assignment orders 2, 3, 4, and 5 can be determined for each slot (index 0 → 1 → 4 → 3) in order of increasing interference levels.

[0110] A low interference level means that the data transmission frequency of adjacent cells in that slot is low. These slot-specific interference levels are measured, processed, and derived differently for each cell (e.g., Cell 1, 2, ...).

[0111] In other words, the present invention uses a method to schedule data to the slot with the lowest interference level, based on the slot-specific interference level within a group derived through processing (e.g., average calculation) of slot-specific interference levels for each cell (e.g., Cell1, 2, ...). This allows the scheduling occupancy rate to be distributed among cells rather than concentrated in the same location (e.g., the first downlink / uplink slot), thereby reducing the probability of inter-cell interference occurring.

[0112] Figure 6 is an illustrative diagram showing the effect of avoiding inter-cell interference obtained by applying the present invention.

[0113] Figure 6 shows the existing situation where the proposed technology of the present invention is "not applied". As can be seen, in Cells 1 and 2, in the case of DL, data transmitted from the upper layer of uplink transmission is buffered before data is scheduled and transmitted from the first slot position where DL transmission is possible.

[0114] This shows that, because the scheduling occupancy rate is high at the same location (e.g., the first DL slot) in both adjacent Cells 1 and 2, interference is highly likely to occur in 8 DL slots between Cells 1 and 2.

[0115] On the other hand, Figure 6 shows the "application of the proposed technology" of the present invention (e.g., four DL slots are configured as one group).

[0116] As you can see, in Cells 1 and 2, the interference levels for each slot are measured, processed, and derived in a way that they are different. This is then used to determine and schedule the allocation order of the slots within the group, which is also different.

[0117] Therefore, when applying the present invention, as with existing systems, in Cell 1 and 2, in the case of DL, data transmitted from the upper layer of uplink transmission is buffered before scheduling and transmitting the data from the first slot position where DL transmission is possible. However, since the allocation order of slots within the group differs for each cell, the scheduling occupancy rate is not concentrated in the same position (e.g., the first DL slot) but is distributed among the cells, which reduces the probability of inter-cell interference (8 DL slots → 4 DL slots).

[0118] Furthermore, the present invention can be extended to techniques for determining not only the allocation order of slots within a group, but also the allocation order of RBs within each slot.

[0119] For example, Figure 7 shows an embodiment in which the present invention can be applied to determine that the allocation order of slots within a group is the same, but the allocation order of RBs within each slot is different.

[0120] As can be seen from Figure 7, by applying this method to determine the allocation order of RBs within a slot, the probability of inter-cell interference can be reduced even when the amount of data to be transmitted is less than one slot, thus effectively eliminating the effects of inter-cell interference.

[0121] As described above, according to the present invention, by scheduling traffic (downlink / uplink) in groups within each cell and determining and scheduling the allocation order of resources (subframes, slots, RBs) within each group differently for each cell, it is possible to distribute the scheduling occupancy among cells so that it is not concentrated in the same location (e.g., the first downlink / uplink slot).

[0122] As a result, according to the present invention, it is possible to move away from existing scheduling methods, which are characterized by high scheduling occupancy rates at the same location (e.g., the first downlink / uplink slot) among cells, and distribute scheduling occupancy rates among cells, thereby avoiding inter-cell interference and improving downlink / uplink transmission performance.

[0123] On the other hand, as described above, the interference level for each unit resource (subframe, slot, RB) measured in the relevant cell is used as a criterion for determining the allocation order of unit resources (subframe, slot, RB) within a group.

[0124] In addition, the present invention can be extended to a method for determining the allocation order of unit resources (subframes, slots, RBs) within a group by utilizing a variety of criteria.

[0125] As an example, the present invention can also use cell information (e.g., PCI, Physical CellIdentifier) ​​to determine the allocation order of unit resources (subframes, slots, RBs) within a group.

[0126] As another example, the present invention also allows for the determination of the allocation order of unit resources (subframes, slots, RBs) within a group using a third external device such as the RIC (RAN Intelligent Controller) of an O-RAN system.

[0127] First, referring to Figure 8, we will explain an example of determining the assignment order using cell information (e.g., PCI).

[0128] In this invention, N distinct assignment sequences are defined in advance, and the assignment sequence can be determined from among the defined N assignment sequences based on the result of a MOD N calculation applied to the PCI (or cell ID) of the cell.

[0129] For example, Figure 8 shows an embodiment of an FDD system in which six slots form a group, with three slots having a predetermined allocation order that differs from one another.

[0130] In this case, assuming a cell with PCI=103, the result of the MOD N (N=3) calculation on PCI=103 is 1. Therefore, in this invention, traffic (downlink / uplink) is assigned / scheduled to the cell in units of groups (6 DL / UL slots), and when assigning / scheduling traffic by group, it is possible to assign / schedule according to the assignment order (5, 6, 1, 2, 3, 4) defined for PCI MOD3=1 among the three assignment orders (PCI MOD3=0, 1, 2).

[0131] As can be seen from Figure 8, the predefined assignment order can be configured in a way that minimizes overlap between them. Therefore, the probability of interference occurring between cells with different PCI MOD values ​​is lower than when the proposed invention is not applied.

[0132] Therefore, in the case of Figure 8, if the amount of data transmitted from a cell with PCI=103 is within 2 slots, it should not interfere with the first two slots of adjacent cells whose MOD N (N=3) calculation result is 0 or 2.

[0133] Next, with reference to Figure 9, we will explain an example of determining the assignment order using a third external device (RIC).

[0134] As shown in Figure 9A, in the present invention, an external device (RIC) can determine the allocation order of unit resources (subframes, slots, RBs) within a group to each cell based on the geographical location information of the cell (Case #1).

[0135] In other words, as can be seen from Case #1 in Figure 9, the external device (RIC) knows the location information for each RU / cell of each base station device, and in the present invention, based on this, the external device (RIC) can determine the assignment order for each RU / cell so that the assignment order between adjacent cells does not overlap as much as possible.

[0136] Case #1 in Figure 9A shows an example of determining the assignment order of slots within two types of groups (bundles) based on the cell's position information.

[0137] For convenience, let's assume the cells are located in one dimension. In Case #1 of Figure 9A, inter-cell interference can be avoided by adjacent cells crossing / determining and communicating that they have different slot allocation orders within different groups.

[0138] On the other hand, as shown in Figure 9B, in the present invention, an external device (RIC) can determine the allocation order of unit resources (subframes, slots, RBs) within a group to each cell based on slot-specific transmission success rate information collected from each base station device (or DU) (Case #2).

[0139] In other words, as can be seen from Case #2 in Figure 9B, the external device (RIC) can collect transmission success rate information for each slot from each base station device (or DU), predict inter-cell interference based on this, and determine the allocation order of slots within the group to each cell in a manner that mitigates it.

[0140] Specifically, the external device (RIC) can determine the allocation order of slots within a group for each cell by updating the allocation order of slots already assigned to the cell based on the collected slot-by-slot transmission success rate information.

[0141] For example, as shown in the table in Case #2 of Figure 9B, if the transmission success rate of slot index 3 has dropped significantly, but it has been assigned the highest existing / current allocation order, 1, the external device (RIC) can use an update method to reset the allocation order of slots within the group by mutually swapping the allocation orders of the last slot index 2 and slot index 3, even though the transmission success rate is the highest.

[0142] As described above, according to various embodiments of the present invention, by scheduling traffic (downlink / uplink) in groups within each cell and determining and scheduling the allocation order of resources (subframes, slots, RBs) within each group differently for each cell, it is possible to distribute the scheduling occupancy among cells so that it is not concentrated in the same location (e.g., the first downlink / uplink slot).

[0143] As a result, according to the present invention, by moving away from existing scheduling methods characterized by high scheduling occupancy rates at the same location (e.g., the first downlink / uplink slot) across cells, and by presenting a new scheduling technique that enables the distribution of scheduling occupancy rates across cells, it is possible to derive the effects of avoiding inter-cell interference and improving downlink / uplink transmission performance.

[0144] The base station equipment, distributed units, and wireless units, and scheduling methods according to embodiments of the present invention can be embodied in a program instruction form that can be executed through various computer means and recorded on a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, etc., individually or in combination. The program instructions recorded on the medium may be specially designed and configured for the present invention, or they may be known and usable by those skilled in the computer software art. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tapes; optical media such as CD-ROMs and DVDs; magneto-optical media such as floptical disks; and hardware devices specially configured to store and execute program instructions, such as ROMs, RAMs, and flash memory. Examples of program instructions include not only machine code, such as that produced by a compiler, but also high-level language code that can be executed by a computer using an interpreter or the like. The hardware devices may be configured to operate as one or more software modules to perform the operations of the present invention, and vice versa.

[0145] Although the present invention has been described in detail above with reference to preferred embodiments, the present invention is not limited to the above embodiments, and the technical idea of ​​the present invention can be modified or altered in various ways by anyone with ordinary skill in the art to which the present invention belongs, without departing from the gist of the present invention as claimed in the following claims.

Claims

1. In base station equipment, Memory containing instruction words; and, A processor that, by executing the above instruction, allocates traffic to cells according to pre-configured groups of unit resources, and when allocating traffic according to the above groups, determines that the allocation order of the unit resources within the above groups is different in order to avoid inter-cell interference in the above cells; The base station device is characterized in that the processor uses an external device (RIC) to determine the allocation order of unit resources within the group to each cell based on the geographical location information of the cell or the transmission success rate information of the unit resource.

2. In a distributed unit (DU), Memory containing instruction words; and, A processor that, by executing the above instruction, allocates traffic to cells according to pre-configured groups of unit resources, and when allocating traffic according to the above groups, determines that the allocation order of the unit resources within the above groups is different in order to avoid inter-cell interference in the above cells; The processor is a distributed unit characterized in that it uses an external device (RIC) to determine the allocation order of unit resources within the group to each cell based on the geographical location information of the cell or the transmission success rate information of the unit resource.

3. The above processor is The distributed unit according to claim 2, characterized in that when allocating traffic to the above-mentioned groups, the allocation order of unit resources within a group is determined by utilizing the unit resource interference level measured for the above-mentioned cell.

4. The above processor is Based on the interference levels per unit resource measured from the RU (Radio Unit) of the above cell, we will confirm the interference levels per unit resource within the above group. The distributed unit according to claim 3, characterized in that when allocating traffic to the above-mentioned groups, the allocation order of unit resources within a group is determined based on the interference level of each unit resource within that group.

5. The above processor is The distributed unit according to claim 4, characterized in that the allocation order is determined sequentially from the unit resource with the lowest interference level to the unit resource with the highest interference level, based on the interference level of each unit resource within the above group.

6. The above unit resources are, The distributed unit according to claim 2, characterized in that it is a subframe, or each slot within a subframe, or each Resource Block (RB) within a slot.

7. In a scheduling method performed by base station equipment, This includes the step of allocating traffic to cells in groups of pre-configured unit resources; The above step is a scheduling method characterized by determining different allocation orders for unit resources within the above groups when allocating traffic to the above groups in order to avoid inter-cell interference in the above cells, and this determination includes using an external device (RIC) to determine the allocation order of unit resources within the above group to each cell based on the geographic location information of the above cells or the transmission success rate information of the above unit resources.

8. In a scheduling method performed by distributed units (DUs), This includes the step of allocating traffic to cells in groups of pre-configured unit resources; The above step is a scheduling method characterized by determining different allocation orders for unit resources within the above groups when allocating traffic to the above groups in order to avoid inter-cell interference in the above cells, and this determination includes using an external device (RIC) to determine the allocation order of unit resources within the above group to each cell based on the geographic location information of the above cells or the transmission success rate information of the above unit resources.

9. The above steps are: The scheduling method according to claim 8, characterized in that when allocating traffic to the above-mentioned groups, the allocation order of unit resources within a group is determined by utilizing the unit resource interference level measured for the above-mentioned cell.

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