Terminal device, network node, control method, and program for communication control with antenna placement considered

Abstract

To perform appropriate communication control according to the arrangement of antennas in a terminal device.SOLUTION: A terminal device having a plurality of antennas notifies a network to which the terminal device belongs of information that allows identification of at least one of a second antenna that has a predetermined characteristic in common with a first antenna included in the plurality of antennas and a third antenna that does not have the predetermined characteristic in common with the first antenna, among the plurality of antennas.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a communication control technology according to the arrangement of antennas in a terminal device.

Background Art

[0002] In accordance with the standards of the 3rd Generation Partnership Project (3GPP), a wireless communication system in which a plurality of base station devices distributed geographically each provide a wireless communication service to a terminal device within the range where the radio waves they transmit reach is widely used. In such a wireless communication system, various communication controls are executed according to the state of the transmission path between the antenna of the base station device and the antenna of the terminal device.

[0003] In response to the fact that wireless communication is used in various situations, the configuration of terminal devices has also become diversified. For example, not only small terminal devices such as conventional mobile phones, but also terminal devices mounted on large objects such as vehicles can be used. Also, in fixed wireless access (FWA) using a cellular communication system, a wireless device on the user side can be used as a terminal device of the cellular communication system.

Summary of the Invention

Problems to be Solved by the Invention

[0004] Conventionally, when a terminal device has a plurality of antennas, since it is assumed that all of those antennas are arranged inside a small terminal device, the characteristics of the transmission paths between the plurality of antennas and the antenna of the base station device have been treated as being generally common. On the other hand, with the diversification of terminal devices, it is assumed that a plurality of antennas of a terminal device are arranged at positions separated from each other, and the characteristics of the transmission paths between the plurality of antennas and the antenna of the base station device are greatly different. In such a case, it becomes difficult to obtain sufficient communication quality if the characteristics of the transmission paths in the plurality of antennas of the terminal device are treated as being generally common.

Means for Solving the Problems

[0005] The present invention provides a method capable of performing appropriate communication control according to the arrangement of antennas in a terminal device.

[0006] A terminal device according to an aspect of the present invention includes a plurality of antennas, and notification means for notifying a network to which the terminal device belongs of information capable of identifying at least any one of a first antenna included in the plurality of antennas, a second antenna having a predetermined characteristic in common with the first antenna, and a third antenna having a predetermined characteristic not in common with the first antenna.

[0007] A network node according to an aspect of the present invention includes acquisition means for acquiring information capable of identifying at least any one of a first antenna included in a plurality of antennas of a terminal device, a second antenna having a predetermined characteristic in common with the first antenna, and a third antenna having a predetermined characteristic not in common with the first antenna, from the terminal device belonging to a network including the network node; and control means for performing control of communication of the terminal device based on the information, the control being common to the first antenna and the second antenna and different for the first antenna and the third antenna, respectively.

Advantages of the Invention

[0008] According to the present invention, it becomes possible to perform appropriate communication control according to the arrangement of antennas in a terminal device.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Embodiments for Carrying Out the Invention

[0010] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims, and not all combinations of the features described in the embodiments are essential for the invention. Two or more of the features described in the embodiments may be arbitrarily combined. Also, the same or similar configurations are given the same reference numerals, and redundant descriptions are omitted.

[0011] (System Configuration) FIG. 1 shows a configuration example of a wireless communication system according to this embodiment. This wireless communication system can be, for example, a cellular communication system compliant with the 5th generation (5G) standard standardized in the 3rd Generation Partnership Project (3GPP). However, this is just an example, and for example, the following discussions may be applicable to wireless communication systems compliant with conventional standards such as Long Term Evolution (LTE) or standards after the 6th generation, and may also be applicable to wireless communication systems other than cellular communication systems.

[0012] This wireless communication system is configured to include, for example, a base station device 101 and a terminal device 111. Note that the base station device 101 is a radio access network node connected to a core network, and the network may naturally include other network nodes. However, for simplicity of explanation, such a configuration is omitted in FIG. 1. Here, the terminal device 111 has a plurality (at least two) of antennas, and it is assumed that among the plurality of antennas, antenna 121 and antenna 122 are arranged at positions far from antenna 123 and antenna 124. In this case, it is assumed that antenna 121 and antenna 122 generally have the same characteristics with respect to the radio waves reaching from the base station device 101. For example, the reception timing of the radio waves received by antenna 121 and antenna 122 is generally the same timing, and for example, the same settings can be used for the downlink reception timing control such as the timing control for Fourier transform, and the same settings can also be used for the uplink transmission timing control such as timing advance. That is, in the communication via antenna 121 and antenna 122, common communication timing control (timing control in at least one of the uplink and the downlink) can be used. Similarly, it is assumed that antenna 123 and antenna 124 generally have the same characteristics with respect to the radio waves reaching from the base station device 101, and for example, common communication timing control can be applied. On the other hand, it can be assumed that antenna 121 or antenna 122 and antenna 123 or antenna 124 have different characteristics from each other. Therefore, if common communication timing control is applied to antenna 121 and antenna 123, it may become impossible to perform communication appropriately. For example, in the downlink, the appropriate window setting for Fourier transform at antenna 121 may not be appropriate at antenna 123, and it may become impossible to ensure orthogonality.

[0013] Also, for example, the terminal device 111 can communicate with different transmission / reception points in the network using a plurality of panels. In this case, since it is assumed that the characteristics of each panel are significantly different, it may not be appropriate to use common settings for communication using a plurality of panels. Although separate settings can be applied to each of the plurality of antennas, the processing can become more complicated as the number of antennas increases.

[0014] Therefore, in the present embodiment, depending on whether or not the respective predetermined characteristics are common when radio waves arriving from the base station device 101 are detected via a plurality of antennas, it is possible to determine whether to apply the same setting control or different setting controls. For this purpose, the terminal device 111 notifies the base station device 101 (network node in the network), for example, of information that can identify at least one of a second antenna having common predetermined characteristics and a third antenna not having common predetermined characteristics with respect to a first antenna among the plurality of antennas that the own device has. For example, the terminal device 111 can notify the base station device 101 that the antenna 121 has common predetermined characteristics with the antenna 122. Also, the terminal device 111 may notify the base station device 101 that the antenna 121 does not have common predetermined characteristics with the antenna 123 or the antenna 124. Further, the terminal device 111 may notify the base station device 101, for example, that the antenna 121 and the antenna 122 belong to a first group and that the antenna 123 and the antenna 124 belong to a second group. In this case, it can be shown that two antennas belonging to the same group have common predetermined characteristics with each other, and two antennas belonging to different groups do not have common predetermined characteristics with each other. The network node (for example, the base station device 101) performs common communication setting and control for the antenna group having common predetermined characteristics and performs independent communication setting and control for the antenna group not having common predetermined characteristics based on this notification.

[0015] The predetermined characteristic relates to, in one example, the magnitude of the delay observed with respect to the radio waves arriving from the base station device 101 or the base station device 102. Further, the predetermined characteristic may be related to the magnitude of the delay until the radio waves transmitted from each of the antennas 121 to 124 of the terminal device 111 reach the base station device 101 or the base station device 102. Hereinafter, for example, with respect to a predetermined antenna of the terminal device 111, it includes the magnitude of the delay observed by the terminal device 111 in the downlink and the magnitude of the delay observed by the base station device 101 or the base station device 102 in the uplink, and is expressed as the magnitude of the delay in the predetermined antenna. In this case, based on the difference between the magnitude of the delay in the antenna 121 and the magnitude of the delay in other antennas, an antenna whose difference does not exceed a predetermined value is treated as an antenna having the same predetermined characteristic as the antenna 121. Further, an antenna whose difference exceeds the predetermined value may be treated as an antenna having a different predetermined characteristic from the antenna 121. Here, the magnitude of the delay may be the average value of the time difference until the radio waves transmitted from the base station device 101 or the base station device 102 reach the terminal device 111 for each antenna. Also, the magnitude of the delay in each antenna may be specified based on the timing at which the radio wave arrives at any one of the antennas.

[0016] For an antenna group in which the timing when radio waves transmitted from base station device 101 or base station device 102 reach terminal device 111 is sufficiently close, that is, an antenna group having common characteristics regarding the magnitude of delay, common communication timing control can be applied. On the other hand, if the network node applies common communication timing control to antenna groups having non-common characteristics regarding the magnitude of delay, it may be difficult to ensure orthogonality. Therefore, independent communication timing control can be applied to these. The communication timing control may include, for example, setting the timing advance used when transmitting an uplink signal. Also, the network node can notify the terminal device 111 of setting information such that different reception controls can be performed, such as setting Fourier transform windows corresponding to different timings for antenna 121 and antenna 122 and for antenna 123 and antenna 124. Also, for an antenna group having common characteristics regarding the magnitude of delay, the network node can commonly perform the setting and control of uplink transmission power control, and for antenna groups having different characteristics regarding the magnitude of delay, the network node can perform the setting and control of uplink transmission power control independently. It is assumed that antennas with significantly different average delays have different propagation loss magnitudes corresponding to the difference in the magnitude of their average delays. Therefore, common setting and control of transmission power control can be performed for antenna groups having generally common average delays, and setting and control of transmission power control can be performed independently for antenna groups having non-common average delays.

[0017] Also, in one example, a predetermined characteristic relates to the magnitude of the delay spread observed for the radio waves reaching the base station apparatus 101 or the base station apparatus 102 from each of the antennas 121 to 124 of the terminal device 111. In this case, based on the difference between the magnitude of the delay spread for the antenna 121 and the magnitude of the delay spread for other antennas, antennas whose difference does not exceed a predetermined value are treated as antennas having the same predetermined characteristic as the antenna 121. Also, an antenna whose difference exceeds the predetermined value can be treated as an antenna that does not have the same predetermined characteristic as the antenna 121. Further, when calculating the correlation value of the shape of the delay spread for the antenna 121 and the shape of the delay spread, an antenna whose correlation value exceeds a predetermined value may be treated as an antenna having the same predetermined characteristic as the antenna 121. Also, an antenna whose correlation value does not exceed the predetermined value can be treated as an antenna that does not have the same predetermined characteristic as the antenna 121.

[0018] For example, the network node may make the setting of the sounding reference signal (SRS) common for antenna groups having the same delay spread characteristic. On the other hand, for antenna groups having different delay spread characteristics, the SRS setting can be applied independently. Here, the SRS setting may include, for example, the setting of the density of the frequency resources on which the SRS should be transmitted. That is, the number of subcarriers on which the SRS is transmitted can be set to be different for each of the plurality of antennas of the terminal device 111. In this way, by applying a common SRS setting to antenna groups having the same delay spread characteristic and applying independent and separate settings to antenna groups having different delay spread characteristics, it is possible to use an SRS setting suitable for each transmission path for each of a plurality of antennas with significantly different transmission path conditions.

[0019] Also, in one example, a predetermined characteristic relates to the direction in which radio waves transmitted from the base station device 101 or the base station device 102 reach the terminal device 111. In this case, based on the difference between the arrival direction of radio waves at the antenna 121 and the arrival direction of radio waves at other antennas, an antenna whose difference does not exceed a predetermined value is treated as an antenna having the same predetermined characteristic as the antenna 121. Also, an antenna whose difference exceeds the predetermined value can be treated as an antenna having a different predetermined characteristic from the antenna 121. The network node can, for example, make the settings and controls for beam control common for antenna groups having the same characteristic of the arrival direction of radio waves. On the other hand, for antenna groups having different characteristics of the arrival direction of radio waves, the settings and controls for beam control can be applied independently. Here, the settings for beam control can include, for example, the settings of channel state information-reference signal (CSI-RS).

[0020] Note that the above-described predetermined characteristics can be fixedly specified according to the installation positions of antennas 121 to 124 in the terminal device 111. For example, as shown in FIG. 1, when antennas 121 and 122 are arranged at positions close enough to each other and at positions different from antennas 123 and 124, predetermined characteristics can be treated as common between antennas 121 and 122. Similarly, antennas 123 and 124 can also be treated as having common predetermined characteristics. On the other hand, antennas 121 and antennas 123 and 124 are treated as not having common predetermined characteristics, and antennas 122 and antennas 123 and 124 can also be treated as not having common predetermined characteristics. Note that the terminal device 111 may notify the network, together with the above-described information, of information indicating which of the above-described predetermined characteristics are common or not common. Note that this notification can be made, for example, as UE Capability (UE Capability). In this case, the terminal device 111 can perform the above-described notification of capabilities by, for example, transmitting a message (UECapabilityInformation) for notifying the capability information to the base station device 101 in response to an inquiry message (UECapabilityEnquiry) for the capability information from the base station device 101. Further, the base station device 101 can perform, for example, setting of the Radio Resource Control (RRC) layer based on the acquired information, and can execute setting and control for the terminal device 111 using, for example, Downlink Control Information (DCI) or the like.

[0021] (Device Configuration) Next, the configurations of the base station apparatus 101 and the terminal apparatus 111 that execute the above-described processing will be described. FIG. 2 is a diagram showing a hardware configuration example of the base station apparatus 101 and the terminal apparatus 111. In one example, the base station apparatus 101 and the terminal apparatus 111 include a processor 201, a ROM 202, a RAM 203, a storage device 204, and a communication circuit 205. The processor 201 is a computer including one or more processing circuits such as a general-purpose CPU (Central Processing Unit) or an ASIC (Application Specific Integrated Circuit), and reads and executes programs stored in the ROM 202 and the storage device 204 to execute the overall processing of the apparatus and each of the above-described processes. The ROM 202 is a read-only memory that stores information such as programs and various parameters related to the processing executed by the base station apparatus 101 and the terminal apparatus 111. The RAM 203 functions as a workspace when the processor 201 executes a program, and is a random access memory that stores temporary information. The storage device 204 is configured by, for example, a detachable external storage device or the like. The communication circuit 205 includes, for example, a circuit for communicating with other devices. Note that in FIG. 2, one communication circuit 205 is illustrated, but the base station apparatus 101 and the terminal apparatus 111 may have a plurality of communication circuits. Note that the terminal apparatus 111 of the present embodiment includes a plurality of antennas, and the plurality of antennas may be connected to one communication circuit 205, or one or more of the plurality of antennas may be connected to one communication circuit 205 while the other antennas are connected to another communication circuit 205.

[0022] FIG. 3 is a diagram showing a functional configuration example of the terminal device 111. The terminal device 111 includes, for example, an information notification unit 301 and a processing unit 302. The functions shown in FIG. 3 can be realized, for example, when the processor 201 executes programs stored in the ROM 202 and the storage device 204. Note that this is just an example, and some or all of the functions shown in FIG. 3 may be realized by dedicated hardware. Also, FIG. 3 shows only the functions related to this embodiment among the functions of the terminal device 111, and the terminal device 111 may naturally have functions other than those shown in FIG. 3, such as functions that a terminal device in a cellular communication system naturally has.

[0023] The information notification unit 301 notifies the base station device 101 (network) of information that can identify at least one of a combination of antennas having common predetermined characteristics and a combination of antennas not having common predetermined characteristics among the plurality of antennas of the terminal device 111 as described above. In addition to the information, the information notification unit 301 may notify the base station device 101 of information specifying the predetermined characteristics. For example, the information notification unit 301 can notify the base station device 101 of information specifying, as the predetermined characteristics, information such as average delay, delay spread, and arrival direction of radio waves, and information that can identify at least one of a combination of antennas having common predetermined characteristics and a combination of antennas not having common predetermined characteristics. Note that when it is determined in advance which information regarding which of a plurality of types of predetermined characteristics should be notified, the information notification unit 301 may not notify the base station device 101 of the information indicating the predetermined characteristics. The processing unit 302 receives control and setting instruction information from the base station device 101 and executes setting processing and control processing based on the instruction information.

[0024] FIG. 4 is a diagram showing an example of the functional configuration of the base station apparatus 101. The base station apparatus 101 includes, for example, an information acquisition unit 401 and a setting control unit 402. The functions shown in FIG. 4 can be realized, for example, when the processor 201 executes programs stored in the ROM 202 and the storage device 204. Note that this is just an example, and some or all of the functions shown in FIG. 4 may be realized by dedicated hardware. Also, FIG. 4 shows only the functions related to the present embodiment among the functions of the base station apparatus 101, and the base station apparatus 101 may naturally have functions other than those shown in FIG. 4, such as functions that a base station apparatus in a cellular communication system naturally has.

[0025] The information acquisition unit 401 acquires, from the terminal device 111, information that can identify at least one of a combination of antennas having common predetermined characteristics and a combination of antennas having non-common predetermined characteristics among a plurality of antennas of the terminal device 111. Also, when it is not predetermined which of a plurality of types of predetermined characteristics the information is related to, the information acquisition unit 401 can acquire information specifying which of the predetermined characteristics the information that can identify at least one of a combination of antennas having common predetermined characteristics and a combination of antennas having non-common predetermined characteristics is related to. The setting control unit 402 executes setting and control of the terminal device 111 based on the information acquired by the information acquisition unit 401.

[0026] (Flow of processing) Next, an example of the flow of processing executed between the base station apparatus 101 and the terminal device 111 will be described.

[0027] FIG. 5 shows an example of the flow of processing related to uplink transmission power control when a predetermined characteristic relates to the average delay. In this processing, first, for example, when the terminal device 111 enters a connected state, the base station device 101 transmits a message for inquiring about the capability information of the terminal device 111 to the terminal device 111 (S501). Then, in response to the message, the terminal device 111 notifies the base station device 101 of the information on its own capabilities (S502). At this time, the terminal device 111 can notify the base station device 101 that the characteristics of the average delay when radio waves arrive from the base station device 101 are common in the antennas 121 and 122, and similarly, the characteristics of the average delay are common in the antennas 123 and 124. When it is predetermined in advance that antenna classification based on the characteristics of the average delay is to be performed, the notification regarding that the predetermined characteristic is a characteristic related to the average delay may be omitted. In this case, the terminal device 111 may notify the base station device 101 only of information indicating that the antennas 121 and 122 are an antenna group with common predetermined characteristics, and the antennas 123 and 124 are an antenna group with common predetermined characteristics. Also, the terminal device 111 may notify the base station device 101 that the predetermined characteristics are not common between the antenna 121 (or the antenna 122) and the antennas 123 and 124.

[0028] The base station device 101 executes settings and controls for the communication of the terminal device 111 based on the information received in S502. For example, the base station device 101 separately performs the setting of transmission power control for the antennas 121 and 122 and the setting of transmission power control for the antennas 123 and 124. The base station device 101 transmits, for example, an RRC reconfiguration message including the setting of transmission power for each antenna group to the terminal device 111 (S503). In response to this, the terminal device 111 transmits an RRC reconfiguration complete message to the base station device 101 (S504) and finishes the setting. Note that a conventional terminal device cannot notify information capable of specifying at least either an antenna group with common predetermined characteristics or an antenna group without common predetermined characteristics such as in S502. For this reason, the base station device 101 performs one common setting for a plurality of antennas regardless of their arrangement or the like for such a conventional terminal device. In contrast, in this embodiment, the base station device 101 can specify whether a common setting can be used for each of the antennas of the terminal device 111 based on the information acquired from the terminal device 111, and can execute setting control based on the result of the specification.

[0029] Thereafter, the base station device 101 allocates, for example, the frequency and time resources for uplink signal transmission to the terminal device (S505). The terminal device 111 transmits uplink data (physical uplink shared channel PUSCH) using each antenna based on the allocation (S506). The base station device 101 determines, for example, whether transmission power control for each antenna of the terminal device 111 is necessary by measuring a predetermined signal such as a demodulation reference signal (DM-RS) among the signals transmitted from each of the antennas 121 to 124. Here, it is assumed that the base station device 101 determines that the received power of the DM-RS transmitted from the antennas 121 and 122 is low and the transmission power should be increased (S507). In this case, the base station device 101 transmits an instruction to the terminal device 111 to increase the transmission power of the antennas 121 and 122 while not changing the transmission power of the antennas 123 and 124. For example, the base station device 101 can include such an instruction in the downlink control information (DCI) that allocates resources for uplink data transmission to the terminal device 111 and transmit it (S508). Note that, for example, information associating the identification information (such as "A" or "B" in FIG. 5) allocated to each setting in S503 with the transmission power control command can be transmitted to the terminal device 111. When receiving this instruction, the terminal device 111 increases the transmission power of the antennas 121 and 122 and transmits uplink data in the allocated resources using each antenna (S509).

[0030] When receiving the uplink data, the base station device 101 also monitors the DM-RS and continuously executes the transmission power according to the received power. Here, assume that the base station device 101 determines that, for example, the received power of the DM-RS transmitted from the antennas 123 and 124 is high and the transmission power should be reduced (S510). In this case, the base station device 101 reduces the transmission power of the antennas 123 and 124, and on the other hand, transmits an instruction to the terminal device 111 not to change the transmission power of the antennas 121 and 122. For example, the base station device 101 can include such an instruction in the downlink control information (DCI) that allocates resources for uplink data transmission to the terminal device 111 (S511). Then, when receiving this instruction, the terminal device 111 reduces the transmission power of the antennas 123 and 124 and transmits uplink data in the allocated resources using each antenna (S512).

[0031] Note that in FIG. 5, an example is shown where the increase in the transmission power of the antennas 121 and 122 and the decrease in the transmission power of the antennas 123 and 124 are performed at different timings, but these controls may be performed simultaneously. For example, the base station device 101 can include an instruction in the DCI to increase the transmission power of the antennas 121 and 122 and decrease the transmission power of the antennas 123 and 124 and transmit it to the terminal device 111. Note that it is sufficient if the controls of the antennas 121 and 122 and the antennas 123 and 124 are performed independently, and an instruction to increase or decrease the transmission power in all of these antennas may be given. However, also in this case, the instruction can be transmitted for each antenna group having common predetermined characteristics.

[0032] Through the above processing, appropriate transmission power control can be performed for each antenna, and the communication efficiency can be improved.

[0033] FIG. 6 shows an example of the flow of setting control processing related to beam reporting when a predetermined characteristic relates to the direction when radio waves from the base station apparatus 101 reach the terminal apparatus 111. In this processing, as in the case of FIG. 5, first, the base station apparatus 101 transmits a message for inquiring about the capability information to the terminal apparatus 111 (S601). Then, in response to the message, the terminal apparatus 111 notifies the base station apparatus 101 of the information on its own capabilities (S602). At this time, the terminal apparatus 111 can notify the base station apparatus 101 that the characteristics of the direction of arrival (Angle of Arrival, AoA) of radio waves from the base station apparatus 101 are common in the antennas 121 and 122, and similarly, the characteristics of AoA are common in the antennas 123 and 124. When it is previously determined that antenna classification based on the AoA characteristics is performed, the notification regarding the fact that the predetermined characteristic is a characteristic related to AoA may be omitted.

[0034] Based on the information received in S602, the base station apparatus 101 executes setting and control for the communication of the terminal apparatus 111. For example, the base station apparatus 101 transmits an RRC reconfiguration message including settings for beam control and management for each antenna group to the terminal apparatus 111 (S603). In response to this, the terminal apparatus 111 transmits an RRC reconfiguration complete message to the base station apparatus 101 (S604) and finishes the setting. For example, as settings necessary for beam control and management, the base station apparatus 101 notifies the terminal apparatus 111 of the settings of the channel state information-reference signal (CSI-RS) and the settings of its reporting for each antenna group having common predetermined characteristics. Also in this processing, for a conventional terminal apparatus, a single common setting is performed for a plurality of antennas regardless of their arrangement or the like. In contrast, in the present embodiment, based on the information acquired from the terminal apparatus 111, the base station apparatus 101 can specify whether a common setting can be used for each of the antennas of the terminal apparatus 111, and can execute setting control based on the result of the specification.

[0035] Thereafter, the base station apparatus 101 transmits CSI-RS corresponding to the settings for the antennas 121 and 122, for example (S605), and the terminal apparatus 111 measures the CSI-RS using the antennas 121 and 122 (S606). Note that the terminal apparatus 111 may refrain from performing measurements using the antennas 123 and 124 for this CSI-RS. Further, the base station apparatus 101 transmits CSI-RS corresponding to the settings for the antennas 123 and 124, for example (S607), and the terminal apparatus 111 measures the CSI-RS using the antennas 123 and 124 (S608). Note that the terminal apparatus 111 may refrain from performing measurements using the antennas 121 and 122 for this CSI-RS. The terminal apparatus 111 continuously performs measurements of CSI-RS based on the first settings regarding the antennas 121 and 122 using the antennas 121 and 122 (S609). Then, when the measurement results satisfy the conditions specified by the reporting settings regarding the antennas 121 and 122 (S610), the terminal apparatus 111 notifies the base station apparatus 101 of the measurement results (S611). Similarly, the terminal apparatus 111 continuously performs measurements of CSI-RS based on the second settings regarding the antennas 123 and 124 using the antennas 123 and 124 (S612). Then, when the measurement results satisfy the conditions specified by the reporting settings regarding the antennas 123 and 124 (S613), the terminal apparatus 111 notifies the base station apparatus 101 of the measurement results (S614).

[0036] Based on the notified measurement results, the base station apparatus 101 performs beam control and management in the conventional manner. By such processing, it is possible to appropriately perform beam control and management for each antenna, and improve the communication efficiency.

[0037] FIG. 7 shows an example of the flow of sounding reference signal setting control processing when a predetermined characteristic relates to delay spread. Also in this processing, as in the cases of FIGS. 5 and 6, first, the base station apparatus 101 transmits a message for inquiring the terminal apparatus 111 about its capability information (S701). Then, in response to the message, the terminal apparatus 111 notifies the base station apparatus 101 of information on its own capability (S702). At this time, the terminal apparatus 111 can notify the base station apparatus 101 that the delay spread characteristics are common when the radio waves transmitted from the antennas 121 and 122 reach the base station apparatus 101, and that the delay spread characteristics are common in the antennas 123 and 124. Note that when it is predetermined that antenna classification based on the delay spread characteristics is to be performed, the notification regarding that the predetermined characteristic is a characteristic related to AoA may be omitted.

[0038] The base station device 101 executes settings and control for the communication of the terminal device 111 based on the information received in S702. The base station device 101 transmits, for example, an RRC reconfiguration message including settings of sounding reference signals (SRS) for each antenna group to the terminal device 111 (S703). In response to this, the terminal device 111 transmits an RRC reconfiguration complete message to the base station device 101 (S704) and finishes the settings. The base station device 101 can, for example, separately set the subcarrier spacing for transmitting SRS (the density on the frequency axis of SRS) for each of the antennas 121 and 122 and the antennas 123 and 124. Thereafter, the terminal device 111 transmits SRS using the antennas 121 and 122 based on the first setting of SRS for those antennas, and also transmits SRS using the antennas 123 and 124 based on the second setting of SRS for those antennas. Thereby, it is possible to suppress the deterioration of efficiency due to using a common setting between antennas where a large difference in the state of the transmission path is assumed. Note that also in this process, for a conventional terminal device, a single common setting is performed for a plurality of antennas regardless of their arrangement or the like. In contrast, in the present embodiment, the base station device 101 can identify whether a common setting can be used for each of the antennas of the terminal device 111 based on the information acquired from the terminal device 111, and execute setting control based on the result of the identification.

[0039] Note that the processes shown in FIGS. 5 to 7 are merely examples, and processes other than the shown settings and control processes may be executed. In FIGS. 5 to 7, the antennas are described as being classified according to the average delay, AoA, and delay spread. However, in reality, these can be determined only by the antenna arrangement. That is, antennas with an inter-antenna distance within a predetermined range can be treated as having common characteristics as a group, and antennas with an inter-antenna distance exceeding the predetermined range can be treated as having different characteristics. Further, the relationship between the distance and position of the antenna arrangement and the presence or absence of commonality of predetermined characteristics are associated in advance, and at least either the antenna group for which common setting control should be performed or the antenna group for which independent setting control should be performed based on the characteristics used for setting control can be notified from the terminal device to the network. For example, in the above example, regardless of what the predetermined characteristics are, antenna 121 and antenna 122 have common characteristics, and antenna 123 and antenna 124 have characteristics different from those of antenna 121 and antenna 122. However, antenna 123 and antenna 124 are assumed to have common characteristics, but this is not limiting. For example, with respect to the average delay, the characteristics are common between antenna 121 and antenna 122, and also between antenna 123 and antenna 124. However, with respect to the delay spread, the characteristics are common between antenna 121 and antenna 124, and also between antenna 122 and antenna 123, and so on. In this way, a plurality of antennas are classified into antenna groups each including one or more antennas, but the classification may vary depending on predetermined characteristics.

[0040] As described above, it becomes possible to perform appropriate communication control in response to diversification of the antenna arrangement in the terminal device. Therefore, it becomes possible to contribute to Goal 9 of the Sustainable Development Goals (SDGs) led by the United Nations, which is to "build resilient infrastructure, promote sustainable industrialization, and foster innovation."

[0041] The invention is not limited to the above-described embodiments, and various modifications and changes are possible within the scope of the gist of the invention.

Claims

1. A terminal device, comprising: a plurality of antennas; notification means for notifying a network to which the terminal device belongs of information capable of identifying at least one of a first antenna included in the plurality of antennas, a second antenna having a predetermined characteristic in common with the first antenna, and a third antenna not having the predetermined characteristic in common with the first antenna; The terminal device is characterized by having the above.

2. The terminal device according to claim 1, wherein the notification means notifies the network of the information together with the predetermined characteristic.

3. The terminal device according to claim 1 or 2, wherein the predetermined characteristic relates to a magnitude of a delay observed with respect to radio waves arriving from a base station device belonging to the network or a magnitude of a delay observed with respect to radio waves arriving from the terminal device to the base station device.

4. The terminal device according to claim 1 or 2, wherein the predetermined characteristic relates to a magnitude of a delay spread observed with respect to radio waves transmitted from the terminal device and arriving at a base station device belonging to the network.

5. The terminal device according to claim 1 or 2, wherein the predetermined characteristic relates to a direction in which radio waves from a base station device belonging to the network arrive.

6. The terminal device according to any one of claims 1 to 5, wherein the notification means performs the notification of the information in response to a request for information on the capabilities of the terminal device from the network.

7. A network node, comprising: acquisition means for acquiring from a terminal device belonging to a network including the network node, information capable of identifying at least one of a first antenna included in the plurality of antennas of the terminal device, a second antenna having a predetermined characteristic in common with the first antenna, and a third antenna not having the predetermined characteristic in common with the first antenna; control means for controlling communication of the terminal device based on the information, performing common control on the first antenna and the second antenna, and performing different control on the first antenna and the third antenna; The network node is characterized by having the above.

8. The network node according to claim 7, wherein the acquisition means acquires the information together with the predetermined characteristic from the terminal device.

9. The predetermined characteristic relates to the magnitude of the delay observed with respect to the radio wave reaching from the base station device belonging to the network, or the magnitude of the delay observed with respect to the radio wave reaching from the terminal device to the base station device, The control means performs common transmission power control for the first antenna and the second antenna, and performs independent transmission power control for the first antenna and the third antenna, The network node according to claim 7 or 8, characterized in that.

10. The predetermined characteristic relates to the magnitude of the delay of the radio wave reaching from the base station device belonging to the network to the terminal device, The control means performs common communication timing control for the first antenna and the second antenna, and performs independent communication timing control for the first antenna and the third antenna, The network node according to claim 7 or 8, characterized in that.

11. The predetermined characteristic relates to the delay spread observed with respect to the radio wave transmitted from the terminal device and reaching the base station device belonging to the network, The control means performs common sounding reference signal setting for the first antenna and the second antenna, and performs independent sounding reference signal setting for the first antenna and the third antenna, The network node according to claim 7 or 8, characterized in that.

12. The predetermined characteristic relates to the direction in which the radio wave transmitted from the base station device belonging to the network reaches the terminal device, The control means performs common beam control for the first antenna and the second antenna, and performs independent beam control for the first antenna and the third antenna, The network node according to claim 7 or 8, characterized in that.

13. The acquisition means transmits a request for information on capabilities to the terminal device, and acquires the information as a response to the request. The network node according to any one of claims 7 to 12, characterized in that.

14. A control method executed by a terminal device having a plurality of antennas, A control method, including notifying a network to which the terminal device belongs of information capable of identifying at least any one of a first antenna included in the plurality of antennas, a second antenna having a common predetermined characteristic with the first antenna, and a third antenna not having a common predetermined characteristic with the first antenna among the plurality of antennas.

15. A control method executed by a network node, obtaining, from a terminal device belonging to a network including the network node, information capable of identifying at least any one of a first antenna included in the plurality of antennas of the terminal device, a second antenna having a common predetermined characteristic with the first antenna, and a third antenna not having a common predetermined characteristic with the first antenna; based on the information, controlling communication of the terminal device, including performing common control on the first antenna and the second antenna, and performing different control on the first antenna and the third antenna respectively; characterized by including the above.

16. A program for causing a computer to function as the terminal device according to any one of Claims 1 to 6.

17. A program for causing a computer to function as the network node according to any one of Claims 7 to 13.

Images