KR102326158B1 - Base station and operating method thereof and terminal - Google Patents

Abstract

A method of operating a base station is disclosed. An embodiment performs each of a plurality of processes, each of which includes transmitting a pilot signal to the terminal in one or more slots allocated by the base station; channel state for each process performed from the terminal Receive information, calculate a radio capacity for each performed process based on at least one of the performed channel state information for each process, and perform the operation based on at least one of the calculated radio capacities and an error rate Selects one of the selected processes, and transmits data to the terminal based on the channel state information for the selected process.

Description

BASE STATION AND OPERATING METHOD THEREOF AND TERMINAL

The following embodiments relate to a base station and a terminal.

In the current 5G system, a serving cell performs scheduling on a terminal accessing it, and a neighboring cell performs scheduling on a terminal accessing it. Accordingly, the serving cell and the neighboring cell may use the same frequency resource, and inter-cell interference may occur in the overlapping region of the serving cell and the neighboring cell. Such inter-cell interference makes it difficult for a UE to have an optimal downlink speed.

As a related prior art, there is Korean Patent Laid-Open Publication No. 10-2015-0135210 (Title of the invention: an externally attached RF communication module that allows a smartphone to be used as a walkie-talkie, Applicant: LG Electronics Co., Ltd.). The method for supporting interference signal cancellation disclosed in this publication includes receiving scheduling information of the neighboring base station from at least one neighboring base station, and removing the interference signal of a target terminal based on the scheduling information of the at least one neighboring base station. Comprising the steps of configuring a set of auxiliary information, and transmitting the set of auxiliary information for canceling the interference signal of the target terminal to the target terminal.

A method of operating a base station according to an aspect includes: performing each of a plurality of processes, each of which includes transmitting a pilot signal to a terminal in one or more slots allocated to the base station; receiving channel state information for each process performed from the terminal; calculating a radio capacity for each performed process based on at least one of the performed channel state information for each process; selecting one of the performed processes based on at least one of the calculated radio capacities and an error rate; and transmitting data to the terminal based on the channel state information for the selected process.

The performed channel state information for each process may include a rank index, a channel quality index, and a precoding matrix index.

The calculating may include calculating a radio capacity for each performed process based on the performed rank index and channel quality index for each process.

The selecting may include selecting a process having a maximum value among the calculated radio capacities.

The selecting may include: when the calculated radio capacities are equal to each other, performing data transmission corresponding to each of the performed processes; and selecting a process corresponding to data transmission having the lowest error rate among the error rates for each of the performed data transmissions.

The performing may include: transmitting a first pilot signal to the terminal every first period according to a first process among the processes; transmitting a portion of a second pilot signal to the terminal every second period according to a second process among the processes; and transmitting a third pilot signal to the terminal every third period according to a third process among the processes.

The remainder of the second pilot signal may be transmitted to the terminal every second period by a neighboring base station.

The same pilot signal as the third pilot signal may be transmitted to the terminal by the neighboring base station.

The transmission timing of the pilot signal according to each of the above processes may be different from each other without overlapping.

In the transmitting step, when a process set for the single transmission of the base station is selected from among the performed processes, the single transmission is performed, and when a process set for joint transmission is selected from among the performed processes, the neighboring base station and the joint It may include the step of performing the transmission.

The method of operating the base station may further include selecting a neighboring base station based on the measurement report received from the terminal.

The measurement report may be transmitted by the terminal when a difference between the reception strength of the base station and the reception strength of the neighboring base station is within a threshold value.

The base station according to one side includes a communication unit; and a plurality of processes, each of which includes transmitting a pilot signal to a terminal in one or more slots allocated by the base station; Receives the performed channel state information for each process from the terminal through the communication unit, calculates a radio capacity for each performed process based on at least one of the performed channel state information for each process, and and a controller that selects one of the performed processes based on at least one of the calculated radio capacities and the error rate, and transmits data to the terminal through the communication unit based on channel state information for the selected process. .

The performed channel state information for each process may include a rank index, a channel quality index, and a precoding matrix index.

The controller may calculate the radio capacity for each process performed based on the rank index and the channel quality index for each process performed.

The controller may select a process having a maximum value among the calculated radio capacities.

When the calculated radio capacities are the same, the controller performs data transmission corresponding to each of the performed processes, and selects a process corresponding to data transmission with the lowest error rate among the error rates for each of the performed data transmissions. can

The controller may transmit a first pilot signal to the terminal in a first period according to a first process among the processes through the communication unit, and transmit a portion of a second pilot signal to the second terminal according to a second process among the processes. Each period may be transmitted to the terminal through the communication unit, and according to a third process among the processes, a third pilot signal may be transmitted to the terminal through the communication unit at every third period.

The remainder of the second pilot signal may be transmitted to the terminal every second period by a neighboring base station.

The same pilot signal as the third pilot signal may be transmitted to the terminal by the neighboring base station.

The transmission timing of the pilot signal according to each of the above processes may be different from each other without overlapping.

The controller performs the single transmission when a process configured for the exclusive transmission of the base station is selected from among the performed processes, and performs the joint transmission with a neighboring base station when a process configured for joint transmission is selected from among the performed processes can be done

The controller may select a neighboring base station based on the measurement report received from the terminal.

The measurement report may be transmitted by the terminal when a difference between the reception strength of the base station and the reception strength of the neighboring base station is within a threshold value.

The terminal according to one side includes a communication unit; and a controller for receiving a pilot signal for each of the processes from the base station through the communication unit, transmitting channel state information for each of the processes to the base station through the communication unit, and receiving data from the base station through the communication unit. include

The base station calculates a radio capacity for each of the processes based on at least one of the channel state information for each of the processes from the terminal, and calculates a radio capacity for each of the processes based on at least one of the calculated radio capacities and an error rate. It selects one of them, and transmits the data to the terminal based on the channel state information for the selected process.

Embodiments may optimally transmit data to the terminal. Further, embodiments may control inter-cell interference.

1 is a diagram for explaining a mobile communication system according to an embodiment.
2 is a flowchart illustrating a method for optimally transmitting downlink data of a serving base station according to an embodiment.
3 to 4 are diagrams for explaining a CSI-RS transmission time and location of a serving base station and a neighboring base station according to an embodiment.
5 to 6 are diagrams for explaining downlink data transmission for each CSI-RS process according to an embodiment.
7 is a flowchart illustrating an operating method of a base station according to an embodiment.
8 is a block diagram illustrating a base station according to an embodiment.
9 is a block diagram illustrating a terminal according to an embodiment.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. However, since various changes may be made to the embodiments, the scope of the patent application is not limited or limited by these embodiments. It should be understood that all modifications, equivalents and substitutes for the embodiments are included in the scope of the rights.

The terms used in the examples are used for description purposes only, and should not be construed as limiting. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present specification, terms such as “comprise” or “have” are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features It should be understood that this does not preclude the existence or addition of numbers, steps, operations, components, parts, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiment belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

In addition, in the description with reference to the accompanying drawings, the same components are given the same reference numerals regardless of the reference numerals, and the overlapping description thereof will be omitted. In the description of the embodiment, if it is determined that a detailed description of a related known technology may unnecessarily obscure the gist of the embodiment, the detailed description thereof will be omitted.

1 is a diagram for explaining a mobile communication system according to an embodiment.

Referring to FIG. 1 , a mobile communication system 100 includes a plurality of base stations 110 - 1 to 110 - 3 and a terminal 120 . Although FIG. 1 shows three base stations 110-1 to 110-3 and the terminal 120 for convenience of description, the mobile communication system 100 includes three or more base stations and a plurality of terminals.

The mobile communication system 100 may correspond to a 4G system, a 5G system (a stand alone system and/or a non stand alone system), or a higher next-generation mobile communication system.

In FIG. 1 , it is assumed that the base station 110 - 1 is a serving base station of the terminal 120 , and each of the base stations 110 - 2 and 110 - 3 is a neighboring base station. The base station 110-1 may be represented differently as a serving cell, and each of the base stations 110-2 and 110-3 may be represented differently as a neighboring cell.

In FIG. 1 , the terminal 120 is located in a cell overlapping area, so inter-cell interference may occur. The base station 110-1 according to an embodiment may control the inter-cell interference so that the terminal 120 has the maximum speed. More specifically, the base station 110-1 according to an embodiment determines whether the terminal 120 is in an area with inter-cell interference (eg, a cell boundary), and the terminal 120 determines whether there is inter-cell interference. If you are in an area where there is, you can check the channel state by transmitting various combinations of CSI-RS (Channel State Information-Reference Signal) (in other words, a pilot signal) to the terminal 120, and based on the check result, the base station ( 110-1) It is possible to coordinate data of itself and a specific neighboring base station and transmit it to the terminal 120 . Accordingly, inter-cell interference can be controlled and the maximum downlink speed can be secured in the terminal 120 .

2 is a flowchart illustrating a method for optimally transmitting downlink data of a serving cell according to an embodiment.

The optimal downlink data transmission method of the serving cell to be described with reference to FIG. 2 may be expressed differently as the optimal downlink data transmission method of the serving base station.

Referring to FIG. 2 , the serving cell determines whether to receive an A3 measurement report from the terminal 120 ( 210 ). Accordingly, the serving cell may determine whether the terminal 120 is in an area with inter-cell interference. For example, the serving cell sets the A3 measurement to the terminal 120 (eg, A3 offset 6dB), and transmits the A3 measurement report when the reception strength of the serving cell and the neighboring cell is within 6dB. Accordingly, if the difference between the reception strength for the serving cell and the reception strength for the neighboring cell is within 6 dB, the terminal 120 may transmit the A3 measurement report to the serving cell.

The A3 measurement report includes information of one or more neighboring cells. As an example, the A3 measurement report may include a Physical Cell Identifier (PCI) and/or Reference Signal Received Power (RSRP) of one or more neighboring cells (eg, one or more neighboring base stations 110-1 and 110-2). can, but is not limited thereto.

If the serving cell does not receive the A3 measurement report from the terminal 120, the serving cell performs data transmission based on a first CSI-RS process to be described later (211).

When the serving cell receives the A3 measurement report from the terminal 120 , it selects a neighboring cell based on the A3 measurement report ( 212 ). For example, upon receiving the A3 measurement report from the terminal 120 , the serving cell may select a neighboring cell by using PCI and/or RSRP in the A3 measurement report. In other words, the A3 measurement report may include the PCI and/or RSRP of each of the neighboring base stations 110-1 and 110-2, and the serving base station 110-1 may include the PCI and/or RSRP in the A3 measurement report. can be used to select one of the neighboring base stations 110-1 and 110-2.

The serving cell performs a plurality of CSI-RS processes (213). Table 1 below shows an example of each CSI-RS process.

First CSI-RS process Second CSI-RS process Third CSI-RS process Transmission Slot Period (P) P1=10 × N1 P2=10 × N2 P3=10 × N3 Transmission Slot t1, t1+P1, t1+2P1, … t2, t2+P2, t2+2P2, … t3, t3+P3, t3+2P3, … Transmission Slot (Example) 1, 11, 21, 31, .. 6, 26, .. 16, 36, .. serving cell CSI-RS 8 port transmission CSI-RS 4 port transmission CSI-RS 8 port transmission selected neighboring cells CSI-RS not transmitted CSI-RS 4 port transmission CSI-RS 8 port transmission

The CSI-RS transmission time for each CSI-RS process may be set or changed by an operator or an administrator. In other words, N1, N2, N3, t1, t2, and t3 may be set or changed. In addition, CSI-RSs transmitted between CSI-RS processes do not overlap and may be transmitted in a downlink (DL) allocation slot.

According to an embodiment, the scrambling ID used by the serving cell and the selected neighboring cell in the second CSI-RS process and the third CSI-RS process may be the same.

As an example, the serving cell may transmit the first CSI-RS to the UE 120 in each of slots 1, 11, 21, and 31 according to the first CSI-RS process. In addition, the serving cell may transmit a portion of the second CSI-RS to the terminal 120 in each of slots 6 and 26 according to the second CSI-RS process. In this case, the selected neighboring cell may transmit the remainder of the second CSI-RS to the UE 120 in each of slots 6 and 26 according to the second CSI-RS process. In addition, the serving cell may transmit the third CSI-RS to the terminal 120 in each of slots 16 and 36 according to the third CSI-RS process. In this case, the selected neighboring cell may transmit the third CSI-RS to the terminal 120 in each of slots 16 and 36 according to the third CSI-RS process.

The CSI-RS transmission time and location of the serving cell and the selected neighboring cell will be described in detail with reference to FIGS. 3 to 4 .

The serving cell receives a plurality of channel state information for each CSI-RS process from the terminal 120 (214). For example, when the serving cell transmits the first CSI-RS to the terminal 120 in the first CSI-RS process, a Rank Index (RI), a Channel Quality Index (CQI), and a Precoding (PMI) from the terminal 120 Matrix Index) can be received. RI, CQI, and PMI received through the first CSI-RS process are expressed as RI_1, CQI_1, and PMI_1 for convenience. In addition, when a portion of the second CSI-RS is transmitted to the UE 120 in the second CSI-RS process, the serving cell may receive RI, CQI, and PMI from the UE 120 . RI, CQI, and PMI received through the second CSI-RS process are expressed as RI_2, CQI_2, and PMI_2 for convenience. In addition, when the serving cell transmits the third CSI-RS to the terminal 120 in the third CSI-RS process, the serving cell may receive the RI, CQI, and PMI from the terminal 120 . RI, CQI, and PMI received through the third CSI-RS process are expressed as RI_3, CQI_3, and PMI_3 for convenience. In summary, the plurality of channel state information for the first CSI-RS process may correspond to RI_1, CQI_1, and PMI_1, and the plurality of channel state information for the second CSI-RS process is RI_2, CQI_2, and PMI_2. may correspond, and the plurality of channel state information for the third CSI-RS process may correspond to RI_3, CQI_3, and PMI_3.

The serving cell calculates the radio capacity for each CSI-RS process (215). As an example, the serving cell may calculate the radio capacity C for each CSI-RS process according to Equation 1 below.

For example, the serving cell may calculate the radio capacity C1 for the first CSI-RS process based on RI_1 and CQI_1 according to Equation 1 above, and calculate the radio capacity C2 for the second CSI-RS process in the above equation 1 may be calculated based on RI_2 and CQI_2, and the radio capacity C3 for the third CSI-RS process may be calculated based on RI_3 and CQI_3 according to Equation 1 above.

The serving cell checks whether the radio capacity for each CSI-RS process is equal to each other (216).

If the serving cell has different radio capacities for each CSI-RS process, it selects the CSI-RS process for which the maximum radio capacity is calculated (217), and transmits data based on the channel state information received through the selected CSI-RS process to the terminal ( 120) (218). For example, when the radio capacity is calculated as shown in Table 2 below, the serving cell may select the second CSI-RS process.

First CSI-RS process Second CSI-RS process Third CSI-RS process CQI 12 14 10 RI 2 3 3 C 42 75 51

When the second CSI-RS process is selected, the serving cell may perform downlink data transmission based on RI_2, CQI_2, and PMI_2 received from the UE 120 through the second CSI-RS process. As will be described later with reference to FIGS. 5 to 6 , since the serving cell has selected the second CSI-RS process, it performs joint transmission with the selected neighboring cell to transmit downlink data to the terminal 120 . Unlike the example of Table 2 above, the serving cell transmits downlink data to the terminal 120 by performing joint transmission with the selected neighbor cell even when the third CSI-RS is selected because the radio capacity C3 is the maximum. However, when the serving cell selects the first CSI-RS process because the radio capacity C1 is the maximum, it transmits the downlink data to the terminal 120 alone.

Downlink data transmission for each CSI-RS process will be described later with reference to FIGS. 5 to 6 .

When the radio capacity for each CSI-RS process is the same, the serving cell performs data transmission corresponding to each CSI-RS process (219), and selects a CSI-RS process corresponding to data transmission with a minimum error rate (220) ), transmits data to the terminal 120 based on the channel state information received through the selected CSI-RS process (218). As an example, the serving cell may perform data transmission in slot 0 based on the first CSI-RS process. The serving cell may perform data transmission in slot 1 based on the second CSI-RS process. At this time, the serving cell may perform joint transmission with the selected neighbor cell as described above. The serving cell may perform data transmission in slot 2 based on the third CSI-RS process. At this time, the serving cell may perform joint transmission with the selected neighbor cell as described above. The serving cell may compare block error rates (BLERs) of slots 0 to 2, and may select a CSI-RS process corresponding to data transmission having the lowest BLER. When BLER in Slot 0 is the lowest, the serving cell may select the first first CSI-RS process, and downlink data transmission based on RI_1, CQI_1, and PMI_1 received through the first CSI-RS process. can be done

Depending on the implementation, C1 and C2 may be the same and greater than C3. In other words, C1=C2>C3. In this case, the serving cell may perform data transmission based on the first CSI-RS process in slot 0, and may perform joint data transmission based on the second CSI-RS process in slot 1. The serving cell may compare BLERs of slots 0 to 1, select a CSI-RS process corresponding to data transmission having the lowest BLER, and perform downlink data transmission based on the selected CSI-RS process.

3 to 4 are diagrams for explaining a CSI-RS transmission time and location of a serving cell and a neighboring cell according to an embodiment.

Referring to FIG. 3, slots 0 to 39 are shown.

In FIG. 3, an example of a slot in which each CSI-RS process is used is marked.

For the example shown in FIG. 3 , slots 1, 11, 21, and 31 are used in the first CSI-RS process, slots 6 and 26 are used in the second CSI-RS process, and slots 16 and 36 are It is used in the third CSI-RS process. In other words, the serving cell may transmit the first CSI-RS to the terminal 120 in slots 1, 11, 21, and 31 through the first CSI-RS process, and the slots through the second CSI-RS process. A part of the second CSI-RS may be transmitted to the UE 120 in steps 6 and 26, and the third CSI-RS may be transmitted to the UE 120 in slots 16 and 36 through the third CSI-RS process.

An example of the location of the CSI-RS is shown in FIG. 4 .

Referring to FIG. 4 , in slots 1 , 11 , 21 , and 31 , the serving cell may transmit the first CSI-RS to the UE 120 through marked resource elements.

In slots 6 and 26, the serving cell may transmit a portion of the second CSI-RS to the UE 120 through the marked resource elements, and the selected neighboring cell may transmit the remainder of the second CSI-RS through the marked resource elements. may be transmitted to the terminal 120 .

In slots 16 and 36, the serving cell may transmit the third CSI-RS to the terminal 120 through the marked resource elements, and the selected neighboring cell transmits the third CSI-RS to the terminal 120 through the marked resource elements. can be sent to In other words, in slots 16 and 36, the serving cell and the selected neighboring cell may transmit the same CSI-RS to the UE.

According to an embodiment, the serving cell may configure a CSI-RS pattern and location to the UE in accordance with Table 3 below by RRC (Radio Resource Control) signaling.

Since Table 3 above refers to 3GPP TS 38.211, a detailed description thereof will be omitted.

Also, according to an embodiment, the serving cell may generate a CSI-RS sequence according to 7.4.1.5.2 Sequence generation of 3GPP TS 38.211.

5 to 6 are diagrams for explaining downlink data transmission for each CSI-RS process according to an embodiment.

5 shows the downlink data transmission when the first CSI-RS process is selected.

When the serving cell selects the first CSI-RS process, it transmits downlink data to the terminal 120 alone.

6 shows downlink data transmission when the second CSI-RS process or the third CSI-RS process is selected.

When the serving cell selects the second CSI-RS process or the third CSI-RS process, the serving cell jointly transmits downlink data between the serving cell and the selected neighboring cell.

Table 4 below is an example of downlink data transmission for each CSI-RS process.

When selecting the first CSI-RS process When selecting the second CSI-RS process When selecting the third CSI-RS process Whether the serving cell performs downlink transmission O O O Whether the downlink transmission of the selected neighboring cell is performed X O O

7 is a flowchart illustrating an operating method of a base station according to an embodiment.

Referring to FIG. 7 , the base station 110 - 1 performs each of a plurality of processes ( 710 ). In this case, each of the processes includes transmitting a pilot signal to the terminal in one or more slots allocated to the base station 110 - 1 .

As an example, the base station 110 - 1 may transmit a first pilot signal to the terminal 120 in a first period according to a first process among processes. Here, the first process may correspond to the above-described first CSI-RS process, and the first period may correspond to N1 of Table 1 described above.

The base station 110 - 1 may transmit a portion of the second pilot signal to the terminal 120 every second period according to a second process among the processes. Here, the second process may correspond to the above-described second CSI-RS process, and the second period may correspond to N2 of Table 1 described above. The remainder of the second pilot signal may be transmitted to the terminal 120 every second period by a neighboring base station selected by the base station 110 - 1 .

The base station 110 - 1 may transmit a third pilot signal to the terminal 120 every third period according to a third process among the processes. Here, the third process may correspond to the third CSI-RS process described above, and the third period may correspond to N3 of Table 1 described above. The same pilot signal as the third pilot signal may be transmitted to the terminal 120 by a neighboring base station selected by the base station 110 - 1 .

In an embodiment, the transmission timing of the pilot signal according to each of the processes may be different from each other without overlapping. Since this has been described with reference to FIGS. 3 to 4 , a detailed description thereof will be omitted.

The base station 110-1 receives channel state information for each process performed from the terminal 120 (720). For example, the base station 110 - 1 may receive the RI, CQI, and PMI for each of the first CSI-RS process to the third CSI-RS process from the terminal 120 . In other words, the base station 110-1 may receive RI_1, CQI_1, and PMI_1 from the terminal 120 through the first CSI-RS process, and RI_2, CQI_2, and PMI_2 through the second CSI-RS process It may be received from the terminal 120 , and RI_3 , CQI_3 , and PMI_3 may be received from the terminal 120 through the third CSI-RS process.

The base station 110 - 1 calculates a radio capacity for each process performed based on at least one of the performed channel state information for each process ( 730 ). As an example, the base station 110-1 may calculate the radio capacity C1 for the first CSI-RS process based on RI_1 and CQI_1 received through the first CSI-RS process, and through the second CSI-RS process The radio capacity C2 for the second CSI-RS process may be calculated based on the received RI_2 and CQI_2, and the radio capacity for the third CSI-RS process based on the RI_3 and CQI_3 received through the third CSI-RS process C3 can be calculated.

The base station 110 - 1 selects one of the performed processes based on at least one of the calculated radio capacities and the error rate ( 740 ).

As an example, the base station 110 - 1 may select a process having a maximum value among the calculated radio capacities. For example, the base station 110 - 1 may select the first CSI-RS process having C1 when C1 is the largest among the calculated radio capacities C1 to C3 .

As another example, when the calculated radio capacities are the same, the base station 110 - 1 may perform data transmission corresponding to each performed process, and data having the lowest error rate among the error rates for each of the performed data transmissions. A process corresponding to the transmission can be selected. For example, when the calculated radio capacities C1 to C3 are equal to each other, the base station 110 - 1 may sequentially perform data transmission corresponding to each of the first to third CSI-RS processes, and the performed data If the BLER of the data transmission corresponding to the third CSI-RS process among the BLERs for each of the transmissions is the smallest, the third CSI-RS process may be selected.

As another example, when two or more of the calculated radio capacities are the same and the maximum is the same, the base station 110 - 1 may perform data transmission corresponding to each process of the corresponding radio capacities, and each of the performed data transmissions It is possible to select a process corresponding to data transmission with the lowest error rate among the error rates for . For example, when C1 = C2 > C3, the base station 110 - 1 may sequentially perform data transmission corresponding to each of the first to second CSI-RS processes, and If the BLER of data transmission corresponding to the second CSI-RS process among BLERs is the smallest, the second CSI-RS process may be selected.

The base station 110 - 1 transmits data to the terminal 120 based on the channel state information for the selected process ( 750 ). As an example, the base station 110-1 may perform a single transmission when a process (eg, the first CSI-RS process) set as a single transmission of the base station 110-1 is selected from among the performed processes, and , when a process configured for joint transmission (eg, the second or third CSI-RS process) is selected from among the performed processes, joint transmission with the selected neighboring base station may be performed.

Since the details of the serving cell and the selected neighboring cell described with reference to FIGS. 1 to 6 may be applied to the base station 110 - 1 and the selected neighboring base station described with reference to FIG. 7 , a detailed description thereof will be omitted.

8 is a block diagram illustrating a base station according to an embodiment.

Referring to FIG. 8 , the base station 110 - 1 includes a communication unit 810 and a controller 820 .

The communication unit 810 performs 4G communication, 5G communication, or more next-generation mobile communication.

The controller 820 performs each of a plurality of processes.

The controller 820 receives channel state information for each process performed from the terminal 120 through the communication unit 810 .

The controller 820 calculates a radio capacity for each performed process based on at least one of the performed channel state information for each process.

The controller 820 selects one of the performed processes based on at least one of the calculated radio capacities and the error rate.

The controller 820 transmits data to the terminal 120 through the communication unit 810 based on the channel state information for the selected process.

Since the details of the serving cell described with reference to FIGS. 1 to 7 may be applied to the base station 110 - 1 of FIG. 8 , a detailed description thereof will be omitted.

9 is a block diagram illustrating a terminal according to an embodiment.

Referring to FIG. 9 , the terminal 120 includes a communication unit 910 and a controller 920 .

The communication unit 910 performs 4G communication, 5G communication, or more next-generation mobile communication.

The controller 920 transmits the measurement report to the base station 110-1 through the communication unit 910 when the difference between the reception strength of the base station 110-1 and the reception strength of the neighboring base station is within a threshold value. For example, the controller 920 may transmit the above-described A3 measurement report to the base station 110 - 1 through the communication unit 910 .

The controller 920 receives pilot signals for each process from the base station 110 - 1 through the communication unit 910 .

The controller 920 transmits channel state information for each process to the base station 110 - 1 through the communication unit 910 .

The controller 920 receives data from the base station 110 - 1 through the communication unit 910 . According to the implementation, the controller 920 may receive data from the base station 110-1 and the corresponding neighboring base station by joint transmission between the base station 110-1 and the neighbor base station selected by the base station 110-1.

Since the matters described with reference to FIGS. 1 to 8 may be applied to the matters described with reference to FIG. 9 , a detailed description thereof will be omitted.

The device described above may be implemented as a hardware component, a software component, and/or a combination of the hardware component and the software component. For example, devices and components described in the embodiments may include, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable gate array (FPGA). , a programmable logic unit (PLU), microprocessor, or any other device capable of executing and responding to instructions, may be implemented using one or more general purpose or special purpose computers. The processing device may execute an operating system (OS) and one or more software applications running on the operating system. The processing device may also access, store, manipulate, process, and generate data in response to execution of the software. For convenience of understanding, although one processing device is sometimes described as being used, one of ordinary skill in the art will recognize that the processing device includes a plurality of processing elements and/or a plurality of types of processing elements. It can be seen that can include For example, the processing device may include a plurality of processors or one processor and one controller. Other processing configurations are also possible, such as parallel processors.

Software may comprise a computer program, code, instructions, or a combination of one or more thereof, which configures a processing device to operate as desired or is independently or collectively processed You can command the device. The software and/or data may be any kind of machine, component, physical device, virtual equipment, computer storage medium or device, to be interpreted by or to provide instructions or data to the processing device. , or may be permanently or temporarily embody in a transmitted signal wave. The software may be distributed over networked computer systems, and stored or executed in a distributed manner. Software and data may be stored in one or more computer-readable recording media.

The method according to the embodiment may be implemented in the form of program instructions that can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, etc. alone or in combination. The program instructions recorded on the medium may be specially designed and configured for the embodiment, or may be known and available to those skilled in the art of computer software. Examples of the computer-readable recording medium include magnetic media such as hard disks, floppy disks and magnetic tapes, optical media such as CD-ROMs and DVDs, and magnetic such as floppy disks. - includes magneto-optical media, and hardware devices specially configured to store and carry out program instructions, such as ROM, RAM, flash memory, and the like. Examples of program instructions include not only machine language codes such as those generated by a compiler, but also high-level language codes that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the embodiments, and vice versa.

As described above, although the embodiments have been described with reference to the limited embodiments and drawings, various modifications and variations are possible by those skilled in the art from the above description. For example, the described techniques are performed in a different order than the described method, and/or the described components of the system, structure, apparatus, circuit, etc. are combined or combined in a different form than the described method, or other components Or substituted or substituted by equivalents may achieve an appropriate result.

Therefore, other implementations, other embodiments, and equivalents to the claims are also within the scope of the following claims.

Claims (21)

In the operating method of the base station,
performing each of a plurality of processes, each of which includes transmitting a pilot signal to a terminal in one or more slots allocated to the base station;
receiving channel state information for each process performed from the terminal;
calculating a radio capacity for each performed process based on at least one of the performed channel state information for each process;
selecting one of the performed processes based on at least one of the calculated radio capacities and an error rate; and
Data is transmitted to the terminal based on the channel state information for the selected process, and when a process configured for the base station's single transmission is selected from among the performed processes, the single transmission is performed, and among the performed processes When a process set for joint transmission is selected, performing the joint transmission with a neighboring base station
containing,
How the base station works.
According to claim 1,
The performed channel state information for each process is,
including a rank index, a channel quality index, and a precoding matrix index,
The calculating step is
Calculating a radio capacity for each process performed based on a rank index and a channel quality index for each process performed
containing,
How the base station works.
According to claim 1,
The selecting step is
selecting a process having a maximum value among the calculated radio capacities;
containing,
How the base station works.
According to claim 1,
The selecting step is
performing data transmission corresponding to each of the performed processes when the calculated radio capacities are equal to each other; and
selecting a process corresponding to data transmission having the lowest error rate among the error rates for each of the performed data transmissions
containing,
How the base station works.
According to claim 1,
The performing step is,
transmitting a first pilot signal to the terminal every first period according to a first one of the processes;
transmitting a portion of a second pilot signal to the terminal every second period according to a second process among the processes; and
transmitting a third pilot signal to the terminal every third period according to a third process among the processes;
containing,
How the base station works.
6. The method of claim 5,
The remainder of the second pilot signal is transmitted to the terminal every second period by a neighboring base station,
The same pilot signal as the third pilot signal is transmitted to the terminal by the neighboring base station,
How the base station works.
According to claim 1,
The transmission time of the pilot signal according to each of the above processes is different from each other without overlapping,
How the base station works.
delete According to claim 1,
selecting a neighboring base station based on the measurement report received from the terminal
further comprising,
How the base station works.
10. The method of claim 9,
The measurement report is transmitted by the terminal when the difference between the reception strength for the base station and the reception strength for the neighboring base station is within a threshold value,
How the base station works.
In the base station,
communication department; and
performing each of a plurality of processes, each of which includes transmitting a pilot signal to a terminal in one or more slots allocated by the base station; Receives the performed channel state information for each process from the terminal through the communication unit, calculates a radio capacity for each performed process based on at least one of the performed channel state information for each process, and the Selecting one of the performed processes based on at least one of the calculated radio capacities and the error rate, and transmitting data to the terminal through the communication unit based on the channel state information for the selected process, A controller that performs the single transmission when a process configured for exclusive transmission of the base station is selected from among the processes, and performs the joint transmission with a neighboring base station when a process configured for joint transmission is selected from among the performed processes
containing,
base station.
12. The method of claim 11,
The performed channel state information for each process is,
including a rank index, a channel quality index, and a precoding matrix index,
The controller is
Calculating the radio capacity for each process performed based on the rank index and the channel quality index for each process performed,
base station.
12. The method of claim 11,
The controller is
selecting a process with a maximum value among the calculated radio capacities;
base station.
12. The method of claim 11,
The controller is
When the calculated radio capacities are the same, data transmission corresponding to each of the performed processes is performed, and a process corresponding to the data transmission having the lowest error rate among the error rates for each of the performed data transmissions is selected,
base station.
12. The method of claim 11,
The controller is
Transmitting a first pilot signal to the terminal through the communication unit every first period according to a first process among the processes;
Transmitting a portion of a second pilot signal to the terminal through the communication unit every second period according to a second process among the processes;
Transmitting a third pilot signal to the terminal through the communication unit every third period according to a third process among the processes;
base station.
16. The method of claim 15,
The remainder of the second pilot signal is transmitted to the terminal every second period by a neighboring base station,
The same pilot signal as the third pilot signal is transmitted to the terminal by the neighboring base station,
base station.
12. The method of claim 11,
The transmission time of the pilot signal according to each of the above processes is different from each other without overlapping,
base station.
delete 12. The method of claim 11,
The controller is
Selecting a neighboring base station based on the measurement report received from the terminal,
base station.
20. The method of claim 19,
The measurement report is transmitted by the terminal when the difference between the reception strength for the base station and the reception strength for the neighboring base station is within a threshold value,
base station.
In the terminal,
communication department; and
A controller that receives a pilot signal for each process from a base station through the communication unit, transmits channel state information for each of the processes to the base station through the communication unit, and receives data from the base station through the communication unit
including,
The base station is
Calculate a radio capacity for each of the processes based on at least one of the channel state information for each of the processes from the terminal, and one of the processes based on at least one of the calculated radio capacities and an error rate , and transmits the data to the terminal based on the channel state information for the selected process, and when a process set as the exclusive transmission of the base station is selected from among the processes, the exclusive transmission is performed, When a process set for joint transmission is selected from among, performing the joint transmission with a neighboring base station,
terminal.

Images