Base station, wireless communication method, and wireless communication system

Abstract

To provide a base station capable of improving the communication quality between a terminal and a base station, a wireless communication method, and a wireless communication system.SOLUTION: The base station includes: a control unit that performs cooperative control based on regulations on cooperative control between multiple base stations that is preset using spatial information about radio wave propagation in a space around the installation position of the base station; and a communication unit sends and receives signals to a terminal under the control of the control unit.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to a base station, a wireless communication method, and a wireless communication system. [Background technology]

[0002] Interference control techniques are considered in wireless communication systems such as cellular networks.

[0003] For example, a technology is being considered in which a terminal reports the results of measuring the quality of a received signal to a base station, and base stations coordinate control based on the reported reception quality to suppress interference between cells. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-34053 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in cooperative control based on quality measurement results, the communication quality between a terminal and a base station may deteriorate due to, for example, spatial conditions between the terminal and the base station that are not necessarily reflected in the quality measurement results. Therefore, there is room for investigation into communication control that improves the communication quality between the terminal and the base station.

[0006] Non-limiting embodiments of the present disclosure contribute to providing a base station, a wireless communication method, and a wireless communication system that can improve the quality of communication between a terminal and a base station. [Means for solving the problem]

[0007] A base station according to one embodiment of the present disclosure includes a control unit that controls communication with a terminal in cooperation with other base stations based on information regarding communication quality between the base station and the terminal and information regarding spatial conditions that may cause fluctuations in radio wave propagation of a signal transmitted to the terminal, and a communication unit that communicates with the terminal in accordance with the control of the control unit.

[0008] In a wireless communication method according to one embodiment of the present disclosure, a base station controls communication with a terminal in cooperation with other base stations based on information regarding communication quality between the base station and the terminal and information regarding spatial conditions that may cause fluctuations in radio wave propagation of a signal transmitted to the terminal, and communicates with the terminal in accordance with the control of the control unit.

[0009] A wireless communication system according to one embodiment of the present disclosure includes a first base station, a second base station, and a terminal, wherein the first base station includes a control unit that controls communication with the terminal in cooperation with the second base station based on information regarding communication quality between the first base station and the terminal and information regarding spatial conditions that may cause fluctuations in radio wave propagation of a signal transmitted to the terminal, and a communication unit that communicates with the terminal in accordance with the control of the control unit.

[0010] These comprehensive or specific aspects may be realized as a system, an apparatus, a method, an integrated circuit, a computer program, or a recording medium, or may be realized as any combination of a system, an apparatus, a method, an integrated circuit, a computer program, and a recording medium. [Effects of the Invention]

[0011] According to non-limiting examples of the present disclosure, the quality of communication between a terminal and a base station can be improved.

[0012] Further advantages and benefits of an embodiment of the present disclosure will become apparent from the specification and drawings. Such advantages and / or benefits may be provided by some of the embodiments and features described in the specification and drawings, respectively, but not necessarily all of them may be provided to obtain one or more identical features. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 shows a first example of areas covered by two base stations. [Figure 2A] A diagram showing a second example of areas covered by two base stations. [Figure 2B] A diagram showing a third example of an area covered by two base stations. [Figure 3A] FIG. 10 is a diagram showing a first example of cooperative control in one embodiment. [Figure 3B] FIG. 10 is a diagram showing a second example of cooperative control in one embodiment. [Figure 4] FIG. 1 is a diagram illustrating a first configuration example of a wireless communication system according to an embodiment. [Figure 5] FIG. 10 is a diagram illustrating a second configuration example of a wireless communication system according to an embodiment. [Figure 6] FIG. 10 is a diagram illustrating a third configuration example of a wireless communication system according to an embodiment. [Figure 7] Diagram showing an example of base station placement [Figure 8] Figure showing an example of arbitration area design without using spatial information [Figure 9] FIG. 1 is a diagram showing a first example of area design when spatial information is used. [Figure 10] FIG. 2 shows a second example of area design using spatial information. [Figure 11] FIG. 10 is a diagram showing an example of arbitration decision in one embodiment. [Figure 12] A sequence diagram showing the flow of arbitration decisions in one embodiment. [Figure 13] Flowchart showing an example of determining arbitration conditions [Figure 14] FIG. 1 shows an example of the configuration of a base station that uses spatial information for position estimation. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In this specification and drawings, components having substantially the same functions are designated by the same reference numerals, and redundant description will be omitted.

[0015] (One embodiment) <Knowledge that led to this disclosure> For example, in a wireless communication system, a base station forms a wireless communication area (e.g., a cell), and terminals located in that area communicate with the base station by radio. In a wireless communication system, the areas formed by multiple base stations may partially overlap. Signals from multiple base stations may reach the overlapping area. In such an area, cooperation between the base stations to control communication between the base station and the terminal is considered.

[0016] For example, when a base station forms a directional beam in a specific area within a cell and communicates with a terminal located in that area, the areas covered by the beams formed by multiple base stations may overlap. In communication with a terminal located in such an area, the base station that will communicate with the terminal and the beam that the base station will use are determined between the base stations. Hereinafter, the process of determining between the base stations the base station that will communicate with the terminal and the beam that the base station will use may be referred to as "arbitration." The area that can be reached by signals transmitted using the beams of multiple base stations may be referred to as the "arbitration target area."

[0017] 1 is a diagram showing a first example of areas covered by two base stations, base station #1 and base station #2.

[0018] In FIG. 1, area #1 covered by base station #1 and area #2 covered by base station #2 partially overlap. When base station #1 and base station #2 each transmit a signal to a terminal located in this overlapping area (e.g., an arbitration target area), interference may occur at the terminal. Furthermore, when base station #1 and base station #2 receive a signal from a terminal located in the overlapping area, interference may occur at at least one of base stations #1 and #2. Alternatively, when one of base station #1 and base station #2 transmits a signal to a terminal located in the overlapping area and the other of base station #1 and base station #2 receives a signal from a terminal located in the overlapping area, interference may occur at the base stations and / or the terminal.

[0019] In cooperative control between base stations, techniques for avoiding interference when multiple base stations (or cells) transmit and receive signals can be applied.

[0020] For example, in the 3rd generation partnership project (3GPP), inter-cell interference avoidance technologies such as Inter-Cell Interference Coordination (ICIC), coordinated multipoint transmission (CoMP), eICIC, and eCoMP are being considered.

[0021] CoMP includes technologies such as Coordinated Scheduling (CS), which performs scheduling in cooperation between base stations; Coordinated Beamforming (CB), which performs beamforming in cooperation between base stations; Dynamic Point Selection (DPS), which switches base stations (or base station beams) so that the base station with the best conditions among multiple base stations communicates with the terminal; and Joint Transmission (JT), which transmits to a single terminal from multiple base stations in a way that does not interfere with each other and increases gain.

[0022] For example, interference avoidance technology is a technology that performs control to avoid interference based on information (communication quality information) related to the communication quality between a base station and a terminal. The communication quality information may be measured by the terminal, and the measurement result may be fed back (or reported) from the terminal to the base station as the communication quality information.

[0023] For example, in CB, one base station is selected from among multiple base stations based on communication quality information, and the selected base station selects a beam to be used for communication with a terminal. In DPS, a base station is selected from among multiple base stations to communicate with a terminal based on communication quality information.

[0024] However, in control based on communication quality information, if the accuracy of the communication quality information deteriorates, appropriate control cannot be performed, and it may become difficult to avoid interference.

[0025] Furthermore, in control based on communication quality information, the determination result (for example, the selection result of a base station) fluctuates stochastically in accordance with stochastic fluctuations in the channel, which can make it difficult to avoid interference.

[0026] Figure 2A is a diagram showing a second example of areas covered by two base stations. Figure 2B is a diagram showing a third example of areas covered by two base stations. Similar to Figure 1, Figures 2A and 2B show area #1 covered by base station #1 and area #2 covered by base station #2.

[0027] For example, in the case of Figure 2A, the influence of an obstacle x such as a building degrades the propagation characteristics in an area that is non-line of sight (NLOS) from base station #1, and the influence of an obstacle y degrades the propagation characteristics in an area that is non-line of sight (NLOS) from base station #2. Also, in the case of Figure 2B, the influence of an obstacle such as a wall degrades the propagation characteristics in an area that is NLOS from base stations #1 and #2.

[0028] In such a case, there is room for further investigation into the arbitration method that determines how to perform coordinated control between two base stations.

[0029] In this embodiment, appropriate cooperative control is realized by using arbitration based on information (spatial information) about the space around the location where the base station is installed.

[0030] The spatial information is an example of information about spatial conditions that may cause fluctuations in radio wave propagation of a signal transmitted from a base station to a terminal (or a signal transmitted from a terminal to a base station). The spatial information includes spatial information related to radio wave propagation. For example, the spatial information includes location information about the installation location of the base station, obstacle information about obstacles that exist around the installation location of the base station and that obstruct radio wave propagation, and information about the arbitration area.

[0031] The spatial information may include the positional relationship between the installation location where the base station is installed and objects existing around the installation location. Here, the objects may include structures whose positions are fixed (e.g., buildings, terrain) and moving objects whose positions change (e.g., cars, people). The spatial information may include fixed physical conditions of the structures (e.g., relative permittivity, transmittance, and reflectance) and physical conditions of the moving objects (e.g., cars, people). The spatial information may also include physical conditions of the space that is the propagation medium around the installation location of the base station. For example, the physical conditions of the space that is the propagation medium may be information about the weather (e.g., whether there is rain or snow, information about fog, thunder, temperature, and information about the amount of rain or snow).

[0032] The obstacle information may include information about the position, size, shape, and material of the obstacle, as well as parameter information about radio wave propagation, such as the relative dielectric constant of the material that constitutes the obstacle.

[0033] The method of acquiring spatial information is not particularly limited. For example, information about structures with fixed positions may be acquired from map information, topographical information, etc. provided by an external server. Information about moving objects may be extracted by image processing from video (images) taken by a camera capturing the area around the base station, or may be acquired from traffic information and global positioning system (GPS) information provided by an external server. For example, information about vehicle congestion may be acquired from traffic information, or the amount of moving objects may be estimated from image information from a camera, etc. Information about weather may be acquired from weather information (e.g., a weather forecast) provided by an external server, or may be extracted by image processing from video (images) taken by a camera capturing the area around the base station.

[0034] Fig. 3A is a diagram showing a first example of cooperative control in this embodiment, and Fig. 3B is a diagram showing a second example of cooperative control in this embodiment.

[0035] FIG. 3A shows an example of areas covered by two base stations when appropriate cooperative control is performed in the example shown in FIG. 2A. FIG. 3A shows area #1a covered by base station 1-1 and area #2a covered by base station 1-2. FIG. 3B shows an example of areas covered by two base stations when appropriate cooperative control is performed in the example shown in FIG. 2B. FIG. 3A shows area #1b covered by base station 1-1 and area #2b covered by base station 1-2.

[0036] 2A and 2B, the area that is NLOS from the perspective of base station #1 has changed to the area covered by base station 1-2 in Figures 3A and 3B. Also, the area that is NLOS from the perspective of base station #2 in Figures 2A and 2B has changed to the area covered by base station 1-1 in Figures 3A and 3B.

[0037] For example, in Fig. 2A, a terminal located in a position that is NLOS from the viewpoint of base station #1 may establish a wireless connection with base station #1, which may result in a deterioration in the communication quality of the terminal. On the other hand, in Fig. 3A, by using arbitration based on spatial information, a terminal located in a position that is NLOS from the viewpoint of base station 1-1 establishes a wireless connection with base station 1-2 instead of base station 1-1, thereby avoiding a deterioration in the communication quality of the terminal.

[0038] According to this embodiment, it is possible to design an appropriate base station coverage area based on spatial information, and to realize cooperative control through arbitration between base stations.

[0039] For example, arbitration data is generated based on spatial information. The arbitration data is data indicating an arbitration method between base stations or between beams formed by the base stations. The arbitration data will be described later.

[0040] The arbitration data may be generated by the information processing device before the base station is installed. Alternatively, the arbitration data may be generated by the information processing device after the base station is installed and in operation. The function of generating the arbitration data may be incorporated into the base station.

[0041] Below, we will explain a configuration example in which arbitration data is generated by an information processing device and stored in the base station before the base station is installed (hereinafter referred to as the first configuration example), a configuration example in which arbitration data is generated by an information processing device while the base station is installed and operating (hereinafter referred to as the second configuration example), and a configuration example in which a function to generate arbitration data is incorporated into the base station (hereinafter referred to as the third configuration example).

[0042] Fig. 4 is a diagram showing a first configuration example of a wireless communication system according to this embodiment. Fig. 4 shows two base stations, 1-1 and 1-2. Note that the base stations 1-1 and 1-2 may have the same configuration. The following describes a configuration example of the base station 1-1.

[0043] The base station 1-1 includes a wireless communication unit 11, an inter-base station communication unit 12, and a control unit 13.

[0044] The wireless communication unit 11 performs wireless communication with the terminal under the control of the control unit 13. For example, under the control of the control unit 13, the wireless communication unit 11 forms a beam having directivity in the direction in which the terminal is located, and transmits a signal to the terminal using the formed beam and receives a signal from the terminal.

[0045] The inter-base station communication unit 12 is connected to the inter-base station communication unit 12 of another base station 1-2 via the Xn interface. The base station communication unit 12 acquires inter-base station arbitration information from, for example, the control unit 13, and transmits the acquired inter-base station arbitration information to the inter-base station communication unit 12 of the base station 1-2. Alternatively, the base station communication unit 12 receives inter-base station arbitration information from, for example, the inter-base station communication unit 12 of the base station 1-2, and outputs the received inter-base station arbitration information to the control unit 13.

[0046] Although an example has been shown in which the inter-base station communication unit 12 is connected via an Xn interface, the present disclosure is not limited to this. The inter-base station communication unit 12 may be connected to another inter-base station communication unit 12 via an interface different from the Xn interface. The connection between the inter-base station communication units 12 may be a wired connection or a wireless connection. Furthermore, the inter-base station communication unit 12 may be connected to two or more other inter-base station communication units 12. In this case, the connection between the inter-base station communication units 12 may be a mixture of wired and wireless connections.

[0047] The control unit 13 controls wireless communication with the terminal. For example, when cooperative control is performed with other base stations in wireless communication with the terminal, the control unit 13 generates, transmits, and receives information for inter-base station cooperative control.

[0048] The control unit 13 includes a reception quality management unit 131 , an arbitration data storage unit 132 , a first arbitration unit 133 , a second arbitration unit 134 , and a beam management unit 135 .

[0049] The reception quality management unit 131 manages the reception quality of a signal transmitted by a terminal and received by a base station (hereinafter referred to as BS (Base Station) reception quality) and the reception quality of a signal transmitted by a base station and received by a terminal (hereinafter referred to as MS (Mobile Station) reception quality). For example, the reception quality management unit 131 acquires a signal received by base station 1-1 via wireless communication unit 11 and calculates the BS reception quality. The reception quality management unit 131 also transmits a reception quality measurement signal (reference signal) from base station 1-1 to the terminal via wireless communication unit 11. The reception quality management unit 131 then receives a feedback signal including information on the MS reception quality from the terminal via wireless communication unit 11 and acquires the MS reception quality reported from the terminal. The reception quality management unit 131 stores the calculated BS reception quality and the acquired MS reception quality.

[0050] The MS reception quality and / or the BS reception quality may be calculated for each beam formed by the base station 1-1.

[0051] The arbitration data storage unit 132 stores arbitration data (spatial information arbitration data) determined based on spatial information. The arbitration data may be data calculated in advance by an external information processing device or the like. The arbitration data may also be referred to as spatial information arbitration data or arbitration plan data.

[0052] The first arbitration unit 133 performs a first arbitration decision based on the BS reception quality and / or the MS reception quality. The first arbitration unit 133 outputs the result of the first arbitration decision to the second arbitration unit .

[0053] The second arbitration unit 134 executes a second arbitration decision based on the arbitration data and the result of the first arbitration decision. The second arbitration unit 134 outputs the result of the second arbitration decision to the beam management unit 135.

[0054] The beam management unit 135 controls the beams used by the wireless communication unit 11 based on the result of the second arbitration decision obtained from the second arbitration unit 134.

[0055] Fig. 5 is a diagram showing a second configuration example of a wireless communication system according to this embodiment. In Fig. 5, the same components as those in Fig. 4 are denoted by the same reference numerals and their description will be omitted. Fig. 5 shows two base stations, 1-1 and 1-2. Note that the base stations 1-1 and 1-2 may have the same configuration.

[0056] The difference between Figures 4 and 5 is that the arbitration data storage unit 132 in Figure 4 stores arbitration data generated in advance, whereas the arbitration data storage unit 132 in Figure 5 stores arbitration data generated in the core network 2, and the arbitration data is successively updated by the core network 2.

[0057] The core network 2 includes a CU (centralized unit) 21 and a DU (distributed unit) 22 .

[0058] The CU21 acquires spatial information from an external device and generates arbitration data. The spatial information includes, for example, information about obstacles present around the base station 1-1 and / or the base station 1-2. The spatial information may also include information about radio wave propagation around the base station 1-1 and / or the base station 1-2.

[0059] The DU 22 transmits the arbitration data to the arbitration data storage units 132 of the base stations 1-1 and 1-2.

[0060] According to the second configuration example shown in FIG. 5, the arbitration data can be updated in accordance with the temporal fluctuations of information that affect radio wave propagation.

[0061] Fig. 6 is a diagram showing a third example configuration of a wireless communication system according to this embodiment. In Fig. 6, the same components as those in Fig. 4 are denoted by the same reference numerals and will not be described. Fig. 6 shows two base stations, 1-1 and 1-2. The base stations 1-1 and 1-2 may have the same configuration. An example configuration of the base station 1-1 will be described below.

[0062] Fig. 6 differs from Fig. 4 in that it adds arbitration data generation unit 331. While arbitration data generated in advance is stored in arbitration data storage unit 132 in Fig. 4, arbitration data generated in arbitration data generation unit 331 is stored in arbitration data storage unit 132 in Fig. 6, and the arbitration data is successively updated by arbitration data generation unit 331.

[0063] The arbitration data generation unit 331 acquires spatial information from an external device and generates arbitration data. The arbitration data generation unit 331 outputs the arbitration data to the arbitration data storage unit 132.

[0064] According to the third configuration example shown in FIG. 6, the arbitration data can be updated in accordance with the time fluctuations of information that affect radio wave propagation.

[0065] Next, an example of arbitration based on spatial information in this embodiment will be described. Fig. 7 is a diagram showing an example of base station arrangement.

[0066] The installation location of base station 1-1 is described as Location 1, and the installation location of base station 1-2 is described as Location 2. Note that if the arbitration data is generated before the base stations are installed, the installation locations may be the locations where the base stations are planned to be installed.

[0067] Base station 1-1 uses beam 1(n) to communicate with terminals present in area 1(n). Note that n is an identifier that identifies the beam, and beam 1(n) indicates the beam corresponding to identifier n among the beams formed by base station 1-1. For example, if base station 1-1 can form N beams (N is an integer greater than or equal to 1), n ​​is an integer greater than or equal to 1 and less than or equal to N, and base station 1-1 can form beams 1(1) to (N).

[0068] Base station 1-2 uses beam 2(m) to communicate with terminals located in area 2(m). Note that m represents an identifier that identifies the beam, and beam 2(m) represents the beam corresponding to identifier m among the beams formed by base station 1-2. For example, if base station 1-2 can form M beams (M is an integer greater than or equal to 1), m is an integer greater than or equal to 1 and less than or equal to M, and base station 1-2 can form beams 2(1) to 2(M). Note that N and M may be the same or different.

[0069] 7, area 1(n) and area 2(m) overlap. For example, this area corresponds to an arbitration target area. Arbitration may be performed for this area.

[0070] FIG. 8 is a diagram showing an example of an arbitration area design when spatial information is not used.

[0071] The horizontal axis in Fig. 8 represents distance. "Location 1" on the left side of the horizontal axis corresponds to the location of base station 1-1, and "Location 2" on the right side of the horizontal axis corresponds to the location of base station 1-2. The vertical axis in Fig. 8 represents signal power.

[0072] Line 1 in Fig. 8 shows the relationship between the distance from base station 1-1 to the receiving point (e.g., the position of a terminal) and the received power of a signal transmitted by base station 1-1 using beam 1(n). Line 2 in Fig. 8 shows the relationship between the distance from base station 1-2 to the receiving point (e.g., the position of a terminal) and the received power of a signal transmitted by base station 1-2 using beam 2(m). Note that the relationship between distance and received power shown in Fig. 8 is calculated assuming a line of sight (LOS) environment.

[0073] An interference arbitration level is also shown in Fig. 8. Areas where the calculated received power is equal to or lower than the interference arbitration level correspond to interference arbitration areas (area 1(n) and area 2(m) in Fig. 7).

[0074] FIG. 9 is a diagram showing a first example of area design when spatial information is used.

[0075] The horizontal axis in Fig. 9 represents distance. "Location 1" on the left side of the horizontal axis corresponds to the location of base station 1-1, and "Location 2" on the right side of the horizontal axis corresponds to the location of base station 1-2. The vertical axis in Fig. 9 represents signal power.

[0076] Line 3 in Figure 9 shows the relationship between the distance from base station 1-1 to the receiving point (e.g., the location of a terminal) and the received power of a signal transmitted by base station 1-1 using beam 1(n). Line 2 in Figure 9 shows the relationship between the distance from base station 1-2 to the receiving point (e.g., the location of a terminal) and the received power of a signal transmitted by base station 1-2 using beam 2(m). Note that the relationship between distance and received power shown by the solid line in Figure 9 is calculated assuming an NLOS environment as seen from base station 1-1. Also, as in Figure 8, Line 1 in Figure 9 is shown by a dashed line, calculated assuming an LOS environment.

[0077] Line 3 in FIG. 9 shows the relationship between the distance from the base station 1-1 to the reception point and the received power, including the power attenuation that occurs at an obstacle x present at the position "Location x."

[0078] Furthermore, because an NLOS environment is assumed, the received power value is more unstable than in an LOS environment, and the delay spread is larger. Therefore, the solid line in Fig. 9 shows that there is a range in the received power in the range of distance from the position of base station 1-1 to a position farther than "Location x."

[0079] 9, an interference arbitration level (B) lower than the interference arbitration level (A) is set, and an area where the calculated received power is equal to or lower than the interference arbitration level (B) corresponds to the interference arbitration area.

[0080] The range of the interference arbitration area differs between FIG. 8, which assumes an LOS environment without considering obstacle x, and FIG. 9, which assumes an NLOS environment with obstacle x taken into consideration.

[0081] Specifically, the range that belonged to the interference arbitration area in Fig. 8 is included in the area where base station 1-2 has priority in Fig. 9. Also, in Fig. 9, the interference arbitration area has shifted to a range farther away from base station 1-2 than in Fig. 8.

[0082] FIG. 10 is a diagram showing a second example of area design when spatial information is used.

[0083] The horizontal axis in Fig. 10 represents distance. "Location 1" on the left side of the horizontal axis corresponds to the location of base station 1-1, and "Location 2" on the right side of the horizontal axis corresponds to the location of base station 1-2. The vertical axis in Fig. 10 represents signal power.

[0084] Line 4 in Figure 10 shows the relationship between the distance from base station 1-1 to the receiving point (e.g., the location of a terminal) and the received power of a signal transmitted by base station 1-1 using beam 1α(n). Line 2 in Figure 10 shows the relationship between the distance from base station 1-2 to the receiving point (e.g., the location of a terminal) and the received power of a signal transmitted by base station 1-2 using beam 2(m). Note that the relationship between distance and received power shown in Figure 10 is calculated assuming an NLOS environment. Also, in Figure 10, Line 1, which is calculated assuming an LOS environment, is shown as a dashed line, as in Figure 8.

[0085] In Fig. 9, base station 1-1 uses beam 1(n), whereas in Fig. 10, base station 1-1 uses beam 1α(n). Beam 1α(n) has directivity in the same direction as beam 1(n) and is formed with less power than beam 1(n).

[0086] Line 4 in FIG. 10 shows the relationship between distance and received power, including the power attenuation that occurs at an obstacle x present at the position "Location x."

[0087] 10, an interference arbitration level (C) lower than the interference arbitration level (A) is set, and an area where the calculated received power is equal to or lower than the interference arbitration level (C) corresponds to the interference arbitration area.

[0088] 10, beam 1α(n) with lower power than beam 1(n) is used, and therefore the range of distance from the position of base station 1-1 to a position farther than "Location x" corresponds to the priority area of ​​base station 1-2 as indicated by the solid line in Fig. 10. In other words, no interference arbitration area is set in the range of distance from the position of base station 1-1 to a position farther than "Location x."

[0089] In this way, by adjusting the interference arbitration level and / or beam power so that it corresponds to the priority area of ​​base station 1-2, in an area that is an NLOS environment as seen from base station 1-1 and an LOS environment as seen from other base station 1-2, it is possible to set the area as the priority area of ​​base station 1-2, which is an LOS environment, rather than an interference arbitration area.

[0090] 9 and 10 show curves representing the relationship between the distance from a base station to a receiving point (e.g., the position of a terminal) and the received power of a signal transmitted by the base station using a certain beam, but in arbitration decisions using spatial information, numerical values ​​representing predicted values ​​of the propagation characteristics for the beam of the base station corresponding to the arbitration target area may be used. Below, we will explain an example of arbitration decisions based on the relationship between path loss, which represents propagation characteristics, NLOS, and communication quality.

[0091] Fig. 11 is a diagram showing an example of arbitration judgment in this embodiment. Fig. 11 shows an example of arbitration judgment in the case where an area 1(n) covered by beam 1(n) of base station 1-1 and an area 2(m) covered by beam 2(m) of base station 1-2 overlap each other as an arbitration target area.

[0092] The path loss in FIG. 11 indicates the path loss calculated based on the spatial information.

[0093] L1 indicates the magnitude of path loss in area 1(n) when base station 1-1 transmits a signal using beam 1(n), and L2 indicates the magnitude of path loss in area 2(m) when base station 1-2 transmits a signal using beam 2(m). For example, a case where L1≧L2 occurs means that the path loss for a signal transmitted by base station 1-1 using beam 1(n) is equal to or greater than the path loss for a signal transmitted by base station 1-2 using beam 2(m). The greater the path loss, the worse the communication quality, so when L1≧L2 occurs, communication with base station 1-2 may be prioritized.

[0094] 11 indicates the magnitude of NLOS calculated based on spatial information. For example, NLOS may be included as part of the path loss. NLOS may also be factors that increase uncertainty in communication quality, such as fading, multipath, delay spread, and various clutter factors.

[0095] NL1 indicates the magnitude of NLOS in area 1(n) when base station 1-1 transmits a signal using beam 1(n), and NL2 indicates the magnitude of NLOS in area 2(m) when base station 1-2 transmits a signal using beam 2(m). For example, a case where NL1 ≥ NL2 occurs when the NLOS for a signal transmitted by base station 1-1 using beam 1(n) is equal to or greater than the NLOS for a signal transmitted by base station 1-2 using beam 2(m). The larger the NLOS, the worse the communication quality, so when NL1 ≥ NL2, communication with base station 1-2 may be prioritized.

[0096] The path loss and NLOS are calculated based on spatial information. Figure 11 shows four cases classified according to the magnitude relationship between the path loss and the NLOS.

[0097] RSRQ (Reference Signal Received Quality) indicates the received quality. For example, Q1 indicates the received quality measured by a terminal existing in area 1(n) when receiving the signal transmitted by base station 1-1 using beam 1(n), and Q2 indicates the received quality measured by a terminal existing in area 2(m) when receiving the signal transmitted by base station 1-2 using beam 2(m).

[0098] Hereinafter, in each of the four cases according to the difference between the magnitude relationship of the path loss and the magnitude relationship of NLOS, an example of arbitration determination using RSRQ will be described.

[0099] For example, in the case of L1≧L2 and NL1≧NL2, when Q1≧Q2, the communication with the terminal is executed by base station 1-2, and when Q1<Q2, the communication with the terminal is executed by base station 1-2. That is, in the case of L1≧L2 and NL1≧NL2, in both conditions of path loss and NLOS, the communication between base station 1-1 and the terminal is likely to be of worse quality than the communication between base station 1-2 and the terminal. Therefore, in the report of the received quality from the terminal, even if Q1≧Q2, the arbitration based on the reported received quality is not adopted, and the arbitration based on the spatial information is executed.

[0100] For example, in the case where L1 ≥ L2 and NL1 < NL2, when Q1 ≥ Q2, communication with the terminal is executed by base station 1-1, and when Q1 < Q2, communication with the terminal is executed by base station 1-1 or base station 1-2. In this case, even if L1 ≥ L2, since NL1 < NL2 and Q1 ≥ Q2, communication with the terminal is executed by base station 1-1. Also, for example, when Q1 < Q2, the base station for executing communication with the terminal is selected based on at least one of the magnitudes of L1 - L2, NL1 - NL2, and Q1 - Q2. For example, when the magnitude of L1 - L2 is greater than or equal to a threshold value and the magnitude of NL1 - NL2 is less than the threshold value, base station 1-2 is selected; when the magnitude of L1 - L2 is less than the threshold value and the magnitude of NL1 - NL2 is greater than or equal to the threshold value, base station 1-1 is selected; when neither condition is satisfied, the base station may be randomly selected.

[0101] For example, in the case where L1 < L2 and NL1 < NL2, when Q1 < Q2, communication with the terminal is executed by base station 1-1, and when Q1 ≥ Q2, communication with the terminal is executed by base station 1-1. That is, in the case where L1 < L2 and NL1 < NL2, in both the path loss and NLOS conditions, the communication quality between base station 1-2 and the terminal is likely to be worse than the communication quality between base station 1-1 and the terminal. Therefore, in the report of the received quality from the terminal, even if Q1 < Q2, arbitration based on the spatial information is executed without adopting the arbitration based on the reported received quality.

[0102] For example, in the case where L1 < L2 and NL1 ≥ NL2, when Q1 < Q2, communication with the terminal is executed by base station 1-2, and when Q1 ≥ Q2, communication with the terminal is executed by base station 1-1 or base station 1-2. In this case, even though L1 < L2, since NL1 ≥ NL2 and Q1 < Q2, communication with the terminal is executed by base station 1-2. Also, for example, when Q1 ≥ Q2, a base station for executing communication with the terminal is selected based on at least one of the magnitudes of L1 - L2, NL1 - NL2, and Q1 - Q2. For example, when the magnitude of L1 - L2 is greater than or equal to a threshold and the magnitude of NL1 - NL2 is less than the threshold, base station 1-2 is selected; when the magnitude of L1 - L2 is less than the threshold and the magnitude of NL1 - NL2 is greater than or equal to the threshold, base station 1-1 is selected; and when neither condition is satisfied, the base station may be randomly selected.

[0103] Note that in FIG. 11, an example is shown where there are four ways of handling information regarding reception quality according to the magnitude relationship between two path losses and the magnitude relationship between two NLOSs in the mediation between two base stations, but the present disclosure is not limited thereto. For example, the difference between the two path losses may be divided into three or more levels, and the difference between the two NLOSs may be divided into three or more levels. In this case, there may be nine ways of handling information regarding reception quality, or quality information other than RSRQ may be added to the selection of the mediation determination condition.

[0104] Also, in FIG. 11, an example of mediation between the beams of two base stations (beam 1(n) of base station 1-1 and beam 2(m) of base station 1-2) is shown, but the number of beams of the base stations to be mediated may be three or more. In this case, based on the spatial information, mediation is performed among a total of three beams, so there may be three path loss values and three NLOS values.

[0105] 11 illustrates an example in which the areas covered by one beam from each of two base stations are the subject of arbitration, but the present disclosure is not limited to this. For example, when an area covered by two beams, beam 1(n) and beam 1(p), formed by base station 1-1 overlaps with an area covered by two beams, beam 2(m) and beam 2(q), formed by base station 1-2, the overlapping area may also be the subject of arbitration. In this case, arbitration is performed between a total of four beams, so there may be four values ​​of path loss and four values ​​of NLOS.

[0106] Next, the flow of arbitration judgment in this embodiment will be described. Fig. 12 is a sequence diagram showing the flow of arbitration judgment in this embodiment. The processing shown in the sequence diagram of Fig. 12 may be executed, for example, before installing base stations 1-1 and 1-2, or may be executed after installing base stations 1-1 and 1-2.

[0107] The installation location of the base station 1-1 is set (S101). The location of the base station 1-1 is written as Location1.

[0108] The installation location of the base station 1-2 is set (S102). The location of the base station 1-2 is written as Location2.

[0109] The propagation area of ​​beam 1(n) is determined (S103). The propagation area of ​​beam 1(n) corresponds to area 1(n), where n is between 1 and N, and a propagation area is determined for each of the N beams.

[0110] The propagation area of ​​beam 2(m) is determined (S104). The propagation area of ​​beam 2(m) corresponds to area 2(m), where m is between 1 and M, and a propagation area is determined for each of the M beams.

[0111] Information on the set base station locations (Location 1 and Location 2) and beam propagation areas is shared between base station 1-1 and base station 1-2 (S105). Here, the shared information may be referred to as arbitration area shared information. For example, when the propagation area information of each base station (e.g., Area 1(1) to Area 2(N) and Area 2(1) to Area 2(M)) is compared, if Area 1(n) and Area 2(m) overlap, these overlapping areas may be referred to as an arbitration area. Note that the number of arbitration areas is not limited to one (one set).

[0112] Next, the base station 1-1 acquires spatial information in area 1 (S106). The base station 1-2 acquires spatial information in area 2 (S107).

[0113] Next, the base station 1-1 calculates the propagation characteristics of beam 1(n) based on the acquired spatial information (S108). The propagation characteristics may be calculated for each of the N beams. Alternatively, the propagation characteristics of beam 1(n), which forms the arbitration area among the N beams, may be calculated.

[0114] The base station 1-2 calculates the propagation characteristics of beam 2(m) based on the acquired spatial information (S109). The propagation characteristics may be calculated for each of the M beams. Alternatively, the propagation characteristics of beam 2(m), which forms the arbitration area among the M beams, may be calculated.

[0115] The calculated propagation characteristics are shared between the base station 1-1 and the base station 1-2 (S110). Here, the shared information may be referred to as arbitration area propagation characteristic shared information.

[0116] Based on the arbitration area propagation characteristic shared information, arbitration conditions are determined (S111). This process may be executed and shared by either base station 1-1 or base station 1-2. The arbitration conditions may correspond to rules for arbitration decision based on reception quality. An example of the process of S111 will be described later.

[0117] The setting information related to arbitration for each base station is determined and notified (S112). For example, the setting information related to arbitration may include a setting related to rules for arbitration decision based on reception quality. Note that this process may be executed by either base station 1-1 or base station 1-2.

[0118] The base station 1-1 sets arbitration conditions for beam 1(n) (S113), and the base station 1-2 sets arbitration conditions for beam 2(m) (S114).

[0119] The above-described one set of processing from S101 to S114 may be executed once or multiple times after the base stations 1-1 and 1-2 are installed and before the base stations 1-1 and 1-2 start communication with terminals. For example, when the one set of processing from S101 to S114 is executed multiple times, it may be executed periodically or each time there is a change in the spatial information.

[0120] Furthermore, the above-described processes of S101 to S114 may be executed by a device different from base station 1-1 and base station #. For example, in the example of Fig. 5, they may be executed in advance by an external device, and in the example of Fig. 6, they may be executed by CN2.

[0121] The processes of S201 to S204 described below are executed, for example, when communicating with a terminal located in an arbitration area. In the following, an example is shown in which arbitration of cooperative control is performed for a terminal located in an arbitration area corresponding to beam 1(n) of base station 1-1 and beam 2(m) of base station 1-2.

[0122] The base station 1-1 receives communication quality information from the terminal (S201). The base station 1-2 receives communication quality information from the terminal (S202). The received communication quality information, such as a measurement report, may be referred to as an MS measurement report or a US measurement report. The communication quality information may include information on the reception quality of a signal received by the terminal from the base station 1-1. For example, the reception quality information may be at least one of standard specifications such as RSRP (Reference Signal Received Power), RSRQ (Reference Signal Received Quality), RSSI (Received Signal Strength Indicator), and CSI (Channel State Information).

[0123] A first arbitration is performed (S203). The first arbitration is based on information about reception quality. The first arbitration may be performed by the base station 1-1, and the base station 1-2 may obtain the result from the base station 1-1.

[0124] Second arbitration is performed (S204). The second arbitration is based on the result of the first arbitration and spatial information. The second arbitration is performed by the base station 1-1, and the base station 1-2 may obtain the result from the base station 1-1. Based on the result of the second arbitration, the base stations 1-1 and 1-2 perform cooperative control. For example, if one of the base stations 1-1 and 1-2 is selected as a result of the second arbitration, the selected base station communicates with terminals present in the arbitration target area using the beam that is the target of arbitration.

[0125] In the above description, an example of determining the arbitration judgment rule (arbitration condition) will be described with reference to FIG. 13. FIG. 13 is a flowchart showing an example of determining the arbitration condition. For example, the flow shown in FIG. 13 may be executed by S111. Moreover, the flow shown in FIG. 13 corresponds to the example shown in FIG. 11.

[0126] It is determined whether L1 is greater than or equal to L2 (S301). As in the example shown in Fig. 11, L1 indicates the magnitude of path loss in area 1(n) when base station 1-1 transmits a signal using beam 1(n), and L2 indicates the magnitude of path loss in area 2(m) when base station 1-2 transmits a signal using beam 2(m).

[0127] If L1 is equal to or greater than L2 (YES in S301), it is determined whether NL1 is equal to or greater than NL2 (S302). Note that, similar to the example shown in Fig. 11, NL1 indicates the magnitude of NLOS in area 1(n) when base station 1-1 transmits a signal using beam 1(n), and NL2 indicates the magnitude of NLOS in area 2(m) when base station 1-2 transmits a signal using beam 2(m).

[0128] If NL1 is equal to or greater than NL2 (YES in S302), it is determined that base station 1-2 ("BS2" in FIG. 13) will use beam 2(m) to communicate between beam 1(n) of base station 1-1 and beam 2(m) of base station 1-2 (S303). Then, the flow shown in FIG. 13 ends.

[0129] If NL1 is not equal to or greater than NL2 (NO in S302), the base stations (and beams) communicating between beam 1(n) of base station 1-1 and beam 2(m) of base station 1-2 determine to adopt the decision based on communication quality (i.e., the first arbitration decision) (S304).Then, the flow shown in FIG. 13 ends.

[0130] If L1 is not equal to or greater than L2 (NO in S301), it is determined whether NL1 is equal to or greater than NL2 (S305).

[0131] If NL1 is equal to or greater than NL2 (YES in S305), the base stations (and beams) communicating between beam 1(n) of base station 1-1 and beam 2(m) of base station 1-2 determine to adopt the decision based on communication quality (i.e., the first arbitration decision) (S306).Then, the flow shown in FIG. 13 ends.

[0132] If NL1 is not equal to or greater than NL2 (NO in S305), it is determined that base station 1-2 ("BS1" in FIG. 13) will use beam 1(n) to communicate between beam 1(n) of base station 1-1 and beam 2(m) of base station 1-2 (S307). Then, the flow shown in FIG. 13 ends.

[0133] In addition, if there are multiple pairs of beams that form an arbitration target area between the beams formed by base station 1-1 and the beams formed by base station 1-2, the arbitration decision rules (arbitration conditions) may be determined for each pair based on the flow shown in Figure 13.

[0134] As described above, in this embodiment, base station 1 includes control unit 13 that controls communication with terminals in cooperation with other base stations based on information on communication quality between the base station and terminals and information on spatial conditions that may cause fluctuations in radio wave propagation of signals transmitted to the terminals, and wireless communication unit 11 that communicates with the terminals in accordance with the control of control unit 13. With this configuration, even if the reliability of a communication quality report (which may be referred to as an MS communication quality report) reported from a terminal is low, appropriate cooperative control can be performed, thereby realizing cooperative control that improves communication quality.

[0135] In this embodiment, settings (arbitration data) relating to cooperative control of communications between a plurality of base stations for terminals may be set in advance, thereby making it possible to suppress an increase in the processing load on the base station.

[0136] In this embodiment, the arbitration data is dynamically or statically set by the core network, so that even if the spatial information fluctuates or is changed, the arbitration data can be changed, thereby realizing cooperative control that improves communication quality.

[0137] Here, the case where spatial information has changed may correspond to a case where spatial information has changed unintentionally. For example, the case where spatial information has changed includes at least one of a case where structures (e.g., buildings) increase or decrease, a case where the weather changes, and a case where traffic volume increases or decreases. Furthermore, the case where spatial information has been changed may correspond to a case where spatial information is intentionally changed by a user of the wireless communication system (e.g., an administrator who designs station placement). For example, the case where spatial information has been changed includes a case where information regarding the location of a base station is changed. Note that the case where spatial information has changed or been changed may correspond to a case where spatial information changes. Furthermore, the case where spatial information has changed or been changed may correspond to a case where a difference (difference) occurs between two pieces of spatial information (e.g., spatial information at two different points in time).

[0138] In this embodiment, the arbitration data is dynamically or statically set by the base station, so that even if the spatial information fluctuates or is changed, the arbitration data can be changed, thereby realizing cooperative control that improves communication quality.

[0139] Furthermore, according to this embodiment, by using spatial information, it is possible to realize operations, specifications, and implementations that cannot be covered by control based on communication quality. Furthermore, by using spatial information, it is possible to omit processing related to quality measurement in the arbitration algorithm based on communication quality, thereby reducing the time required for initial convergence. Furthermore, when arbitration is learned and optimization is performed using both the arbitration algorithm based on communication quality and spatial information, it is possible to improve the accuracy of convergence to an optimal solution.

[0140] Although the above example shows an example in which spatial information is used for arbitration for cooperative control, the present disclosure is not limited to this.

[0141] For example, the spatial information may be used for estimating the location of the terminal, for example, to improve the estimation accuracy of the location of the terminal by time of arrival (TOA) or time difference of arrival using a position reference signal (PRS) and / or a reference signal time difference (RSTD).

[0142] Fig. 14 is a diagram showing an example of the configuration of a base station that uses spatial information for position estimation. Fig. 14 shows the configuration related to position estimation, and configurations related to processes different from position estimation are omitted. In Fig. 14, the same configurations as in Fig. 4 are assigned the same numbers, and descriptions thereof will be omitted.

[0143] The control unit 13 in FIG. 14 includes a location information management unit 431, a delay data storage unit 432, a TDOA calculation unit 433, and a location estimation unit 434.

[0144] The location information management unit 431 stores and manages the location information of the terminals. For example, the location information management unit 431 stores the location information of the terminals wirelessly connected to the base station 1-1 in association with the identification information of the terminals.

[0145] The delay data storage unit 432 stores information relating to predicted propagation characteristics, such as delay spreads determined based on spatial information.

[0146] The TDOA calculation unit 433 calculates the TDOA based on the reference signal received from the terminal.

[0147] The location estimation unit 434 corrects the TDOA by correcting the time of arrival (TOA) of the reference signal received from the terminal using the delay spread. The location estimation unit 434 estimates the location of the terminal based on the corrected TDOA.

[0148] In this way, by performing correction based on the delay spread calculated from the spatial information, it is possible to improve the estimation accuracy of the position estimation using the corrected arrival time.

[0149] In addition, the notation "··· part" in the above-mentioned embodiments may be replaced with other notations such as "··· circuitry," "··· assembly," "··· device," "··· unit," or "··· module."

[0150] The present disclosure can be realized in software, hardware, or software in conjunction with hardware.

[0151] Each functional block used in the description of the above embodiments may be partially or entirely realized as an LSI, which is an integrated circuit, and each process described in the above embodiments may be partially or entirely controlled by a single LSI or a combination of LSIs. The LSI may be composed of individual chips, or may be composed of a single chip that includes some or all of the functional blocks. The LSI may have data input and output. Depending on the degree of integration, the LSI may be called an IC, system LSI, super LSI, or ultra LSI.

[0152] The integrated circuit method is not limited to LSI, but may be realized by a dedicated circuit, a general-purpose processor, or a dedicated processor. Also, a field programmable gate array (FPGA) that can be programmed after LSI manufacturing, or a reconfigurable processor that can reconfigure the connections and settings of circuit cells within the LSI, may be used. The present disclosure may be realized as digital processing or analog processing.

[0153] Furthermore, if an integrated circuit technology that can replace LSI emerges due to advances in semiconductor technology or other derivative technologies, it is natural that such technology may be used to integrate functional blocks. The application of biotechnology, etc. is also a possibility.

[0154] The present disclosure may be implemented in any type of apparatus, device, or system (collectively referred to as a communications apparatus) that has a communications function. The communications apparatus may include a wireless transceiver and processing / control circuitry. The wireless transceiver may include a receiver and a transmitter, or both functions. The wireless transceiver (transmitter and receiver) may include a radio frequency (RF) module and one or more antennas. The RF module may include an amplifier, an RF modulator / demodulator, or the like. Non-limiting examples of communication devices include telephones (e.g., cell phones, smartphones), tablets, personal computers (PCs) (e.g., laptops, desktops, notebooks), cameras (e.g., digital still / video cameras), digital players (e.g., digital audio / video players), wearable devices (e.g., wearable cameras, smartwatches, tracking devices), game consoles, digital book readers, telehealth / telemedicine devices, communication-enabled vehicles or mobile transportation (e.g., cars, airplanes, ships), and combinations of the above devices.

[0155] Communications equipment is not limited to portable or mobile equipment, but also includes non-portable or fixed equipment, devices, and systems of any kind, such as smart home devices (such as appliances, lighting equipment, smart meters or metering devices, control panels, etc.), vending machines, and any other "things" that may exist on an IoT (Internet of Things) network.

[0156] Furthermore, in recent years, in the field of IoT (Internet of Things) technology, CPS (Cyber ​​Physical Systems) has been attracting attention as a new concept that creates new added value by linking information between physical space and cyberspace. This CPS concept can also be adopted in the above-mentioned embodiments.

[0157] That is, as a basic configuration of a CPS, for example, an edge server located in physical space and a cloud server located in cyberspace can be connected via a network, and processing can be distributed and performed by processors installed on both servers. Here, it is preferable that each piece of processing data generated on the edge server or cloud server is generated on a standardized platform, and the use of such a standardized platform can improve the efficiency of building a system that includes a variety of sensor groups and IoT application software.

[0158] Communications include data communications via cellular systems, wireless LAN systems, communications satellite systems, etc., as well as data communications via combinations of these.

[0159] A communications apparatus also includes devices such as controllers and sensors connected or coupled to a communications device that performs the communications functions described in this disclosure, such as controllers and sensors that generate control and data signals used by the communications device to perform the communications functions of the communications apparatus.

[0160] The communication apparatus also includes infrastructure facilities, such as base stations, access points, and any other apparatus, device, or system that communicates with or controls the various apparatuses listed above, but are not limited to these.

[0161] Although various embodiments have been described above with reference to the drawings, it goes without saying that the present disclosure is not limited to such examples. It is clear that a person skilled in the art can conceive of various modifications or alterations within the scope of the claims, and it is understood that these also naturally fall within the technical scope of the present disclosure. Furthermore, the components of the above-described embodiments may be combined in any manner without departing from the spirit of the disclosure.

[0162] Although specific examples of the present disclosure have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and alterations of the specific examples exemplified above. [Industrial Applicability]

[0163] An embodiment of the present disclosure is suitable for a wireless communication system. [Explanation of symbols]

[0164] 1 base station 2 Core Network 11. Wireless Communication Section 12 Base station communication unit 13 Control Unit 21 CU 22 DU 131 Reception Quality Control Department 132 Arbitration data storage unit 133 1st Mediation Department 134 Second Mediation Department 135 Beam Control Department 331 Arbitration Data Generation Unit

Claims

1. a control unit that controls communication with the terminal in cooperation with other base stations based on information regarding communication quality between the base station and the terminal and information regarding spatial conditions that may cause fluctuations in radio wave propagation of a signal transmitted to the terminal; a communication unit that communicates with the terminal under control of the control unit; Equipped with The control unit When an arbitration area occurs in which the propagation area of ​​the base station overlaps with the propagation area of ​​the other base station, a first propagation characteristic of the beam of the base station that forms the arbitration area and a second propagation characteristic of the beam of the other base station that forms the arbitration area are acquired, the first propagation characteristic being calculated based on information about the spatial conditions; determining an arbitration condition based on the first propagation characteristic and the second propagation characteristic; setting the arbitration conditions to the base station and the other base station; Base station.

2. the control unit predicts radio wave propagation between the base station and the terminal using the information on the spatial conditions, and controls communication with the terminal based on the prediction result. The base station of claim 1 .

3. The control unit controls communication with the terminal based on a change in the information regarding the spatial condition. The base station of claim 2.

4. the control unit acquires setting information regarding communication with the terminal from an information processing device that predicts radio wave propagation between the base station and the terminal using information regarding the spatial conditions; The base station of claim 1 .

5. Setting information regarding communication with the terminal is stored in a storage unit before the base station is installed. The base station of claim 1 .

6. The control unit making an arbitration decision on communication for the terminal based on the communication quality; correcting the result of the arbitration decision based on information about the spatial condition; The base station of claim 1 .

7. the communication unit forms a directional beam through directivity control by the control unit, The control unit controls communication with the terminal based on information regarding the beam coordinated with the other base station. The base station of claim 1 .

8. The information on the beams cooperated with the other base stations indicates beams formed by the base station and the other base stations that overlap in geographical areas. The base station of claim 7.

9. the control unit adjusts the power of the beam coordinated with the other base station based on the information on the spatial condition. The base station of claim 8.

10. the control unit adjusts a threshold used to determine whether to cooperate with the other base station based on the information regarding the spatial condition. The base station of claim 1 .

11. the control unit corrects information about the distance from the base station to the terminal based on the information about the spatial conditions, and estimates the position of the terminal using the corrected information about the distance. The base station of claim 1 .

12. The control unit: determining the arbitration conditions based on an index related to communication quality, a path loss representing propagation characteristics, and a non-linear loss of service (NLOS) indicating factors that increase uncertainty in communication quality, the path loss being calculated based on information related to the spatial conditions; When the trends of the path loss and the NLOS match, arbitration conditions are determined by prioritizing information related to the spatial conditions over the index related to the communication quality. The base station of claim 1 .

13. The base station Controlling communication with the terminal in cooperation with other base stations based on information on communication quality between the base station and the terminal and information on spatial conditions that may cause fluctuations in radio wave propagation of signals transmitted to the terminal; Communicating with the terminal in accordance with the control; When an arbitration area occurs in which the propagation area of ​​the base station overlaps with the propagation area of ​​the other base station, a first propagation characteristic of the beam of the base station that forms the arbitration area and a second propagation characteristic of the beam of the other base station that forms the arbitration area are acquired, the first propagation characteristic being calculated based on information about the spatial conditions; determining an arbitration condition based on the first propagation characteristic and the second propagation characteristic; setting the arbitration conditions to the base station and the other base station; Wireless communication method.

14. a first base station; a second base station; and a terminal; The first base station a control unit that controls communication with the terminal in cooperation with the second base station based on information on communication quality between the first base station and the terminal and information on spatial conditions that may cause fluctuations in radio wave propagation of a signal to be transmitted to the terminal; a communication unit that communicates with the terminal under control of the control unit; Equipped with The control unit When an arbitration area occurs in which the propagation area of ​​the first base station and the propagation area of ​​the second base station overlap, first propagation characteristics of a beam of the first base station that forms the arbitration area and second propagation characteristics of a beam of the second base station that form the arbitration area are acquired, the first propagation characteristics being calculated based on information about the spatial conditions; determining an arbitration condition based on the first propagation characteristic and the second propagation characteristic; setting the arbitration conditions in the first base station and the second base station; Wireless communication system.

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