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

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 technique 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 respectively provide wireless communication services 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 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, if the characteristics of the transmission paths in the plurality of antennas of the terminal device are treated as being generally common, it becomes difficult to obtain sufficient communication quality.

Means for Solving the Problems

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

[0006] A terminal device according to one aspect of the present invention includes a plurality of antennas, a notification means for notifying the network to which the terminal device belongs of information that can identify at least one of the following: a second antenna which shares predetermined characteristics with a first antenna included in the plurality of antennas, and a third antenna which does not share predetermined characteristics with the first antenna. The system includes a receiving means for receiving communication settings to be set for each of the plurality of antennas, wherein the receiving means receives the same communication settings as the first antenna as the communication settings to be set for the second antenna, and receives the communication settings that are at least partially different from those of the first antenna as the communication settings to be set for the third antenna, and the receiving means receives the communication settings to be set for each of the plurality of antennas as settings for the Radio Resource Control (RRC) layer. do.

[0007] A network node according to one aspect of the present invention includes an acquisition means for acquiring information from a terminal device belonging to a network including the network node that can identify at least one of the following: a second antenna having predetermined characteristics in common with a first antenna among the plurality of antennas, and a third antenna having predetermined characteristics in common with the first antenna; and a means for controlling the communication of the terminal device based on the information. The communication settings to be set for each of the aforementioned multiple antennas Control means for performing control, The control means controls the second antenna to be configured with the same communication settings as the first antenna, and controls the third antenna to be configured with communication settings that are at least partially different from those of the first antenna, and transmits the communication settings to be set for each of the plurality of antennas to the terminal device as settings for the Radio Resource Control (RRC) layer. . [Effects 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 explanation of the drawing]

[0009] [Figure 1] This diagram shows an example of the system configuration. [Figure 2] This figure shows an example of the device's hardware configuration. [Figure 3] This figure shows an example of the functional configuration of a terminal device. [Figure 4] This figure shows an example of the functional configuration of a base station device. [Figure 5] This diagram shows an example of the processing flow executed within the system. [Figure 6] This diagram shows an example of the processing flow executed within the system. [Figure 7] This diagram shows an example of the processing flow executed within the system. [Modes for carrying out the invention]

[0010] The embodiments will be described in detail below with reference to the attached drawings. Note that the following embodiments do not limit the invention as defined in the claims, and not all combinations of features described in the embodiments are essential to the invention. Two or more of the features described in the embodiments may be combined in any way. Furthermore, identical or similar configurations will be given the same reference numeral, and redundant descriptions will be omitted.

[0011] (System Configuration) Figure 1 shows an example configuration of the wireless communication system according to this embodiment. This wireless communication system may be, for example, a cellular communication system compliant with the fifth-generation (5G) standard standardized by the Third Generation Partnership Project (3GPP). However, this is just one example, and the following discussion may also apply to wireless communication systems compliant with conventional standards such as Long-Term Evolution (LTE) or sixth-generation and later standards, and may also apply to wireless communication systems other than cellular communication systems.

[0012] This wireless communication system is composed of, for example, a base station device 101 and a terminal device 111. The base station device 101 is a wireless access network node connected to the core network, and the network may naturally include other network nodes, but for the sake of simplicity, such configurations are omitted in Figure 1. Here, the terminal device 111 has multiple (at least two) antennas, and it is assumed that antennas 121 and 122 are located at a distance from antennas 123 and 124. In this case, it is assumed that antennas 121 and 122 have generally similar characteristics with respect to radio waves arriving from the base station device 101. For example, the reception timing of radio waves received by antennas 121 and 122 is generally the same, and the same settings can be used for downlink reception timing control, such as timing control for Fourier transform, and the same settings can also be used for uplink transmission timing control, such as timing advance. In other words, in communication via antennas 121 and 122, a common communication timing control (timing control in at least one of the uplink and downlink) can be used. Similarly, antennas 123 and 124 are assumed to have generally similar characteristics with respect to radio waves arriving from the base station equipment 101, and for example, a common communication timing control can be applied to them. On the other hand, it is possible that antennas 121 or 122 and antennas 123 or 124 have different characteristics from each other. For this reason, if a common communication timing control is applied to antennas 121 and 123, proper communication may not be possible. For example, an appropriate Fourier transform window setting for antenna 121 in the downlink may not be appropriate for antenna 123, making it impossible to guarantee orthogonality.

[0013] Furthermore, for example, terminal device 111 can communicate with different transmitting and receiving points within the network using multiple panels. In this case, since the characteristics of each panel are expected to differ significantly, it may not be appropriate to use common settings for communication using multiple panels. Although separate settings can be applied to each of the multiple antennas, the processing can become more complex as the number of antennas increases.

[0014] Therefore, in this embodiment, when radio waves arriving from the base station device 101 via multiple antennas are detected, it is possible to decide whether to apply the same setting control or different setting control depending on whether the predetermined characteristics of each antenna are common. To this end, the terminal device 111 notifies the base station device 101 (a network node in the network) of information that allows it to identify at least one of the following: a second antenna that shares the predetermined characteristics with a first antenna among the multiple antennas owned by the terminal device, and a third antenna that does not share the predetermined characteristics. For example, the terminal device 111 may notify the base station device 101 that antenna 121 shares the predetermined characteristics with antenna 122. Alternatively, the terminal device 111 may notify the base station device 101 that antenna 121 does not share the predetermined characteristics with antennas 123 or 124. Furthermore, the terminal device 111 may notify the base station device 101 that, for example, antennas 121 and 122 belong to a first group, and antennas 123 and 124 belong to a second group. In this case, it may be indicated that two antennas belonging to the same group share a predetermined characteristic, while two antennas belonging to different groups do not share a predetermined characteristic. Based on this notification, the network node (e.g., the base station device 101) sets up and controls common communication for the group of antennas that share the predetermined characteristic, and independently sets up and controls communication for the group of antennas that do not share the predetermined characteristic.

[0015] The predetermined characteristic, in one example, relates to the magnitude of delay observed for radio waves arriving from base station equipment 101 or base station equipment 102. Alternatively, the predetermined characteristic may relate to the magnitude of delay between the radio waves transmitted from each of the antennas 121-124 of terminal equipment 111 and their arrival at base station equipment 101 or base station equipment 102. In the following, for example, for a predetermined antenna of terminal equipment 111, the magnitude of delay observed by terminal equipment 111 in the downlink and the magnitude of delay observed by base station equipment 101 or base station equipment 102 in the uplink are collectively referred to as the magnitude of delay at that predetermined antenna. In this case, based on the difference between the magnitude of delay at antenna 121 and the magnitude of delay at other antennas, antennas whose difference does not exceed a predetermined value are treated as antennas that share the predetermined characteristic with antenna 121. Conversely, antennas whose difference exceeds a predetermined value may be treated as antennas that do not share the predetermined characteristic with antenna 121. The magnitude of the delay here may be the average time difference between the time it takes for the radio waves transmitted from base station equipment 101 or base station equipment 102 to reach terminal equipment 111 for each antenna. Alternatively, the magnitude of the delay at each antenna may be determined based on the timing at which the radio waves arrive at any one of the antennas.

[0016] Network nodes can apply common communication timing control to groups of antennas where the timing of radio waves transmitted from base station equipment 101 and base station equipment 102 reaching terminal equipment 111 is sufficiently close, i.e., groups of antennas with common delay characteristics. On the other hand, if network nodes apply common communication timing control to groups of antennas with different delay characteristics, it may be difficult to ensure orthogonality, so they can apply independent communication timing control to these groups. Communication timing control may include, for example, setting the timing advance used when transmitting uplink signals. Furthermore, network nodes can notify terminal equipment 111 of setting information that allows for different reception control, such as setting different Fourier transform windows corresponding to different timings for antennas 121 and 122 and antennas 123 and 124. In addition, network nodes can set and control uplink transmission power control commonly for groups of antennas with common delay characteristics, and independently set and control uplink transmission power control for groups of antennas with different delay characteristics. Antennas with significantly different average delays are expected to have different propagation losses, corresponding to the differences in their average delays. Therefore, a common transmit power control setting and control can be applied to groups of antennas with roughly the same average delay, while the transmit power control setting and control can be applied independently to groups of antennas with different 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 device 101 or the base station device 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, 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. 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 having a different predetermined characteristic from the antenna 121.

[0018] For example, the network node can use a common setting for, for example, the sounding reference signal (SRS) for antenna groups having the same delay spread characteristic. On the other hand, for antenna groups having different delay spread characteristics, independent SRS settings can be applied. Here, the SRS setting can include, for example, setting 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 differently 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] Furthermore, the predetermined characteristics relate, in one example, to the direction in which radio waves transmitted from base station equipment 101 or base station equipment 102 reach terminal equipment 111. In this case, based on the difference between the direction of arrival of radio waves at antenna 121 and the direction of arrival of radio waves at other antennas, antennas whose difference does not exceed a predetermined value are treated as antennas that share the predetermined characteristics with antenna 121. Antennas whose difference exceeds a predetermined value may be treated as antennas that do not share the predetermined characteristics with antenna 121. Network nodes may, for example, share the settings and controls for beam control for groups of antennas that share the characteristics of the direction of arrival of radio waves. On the other hand, settings and controls for beam control may be applied independently to groups of antennas that do not share the characteristics of the direction of arrival of radio waves. Here, the settings for beam control may include, for example, the setting of channel status information-reference signal (CSI-RS).

[0020] Note that the above-mentioned 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 those of antennas 123 and 124, the predetermined characteristics of antennas 121 and 122 can be treated as common. 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 of information indicating which of the above-mentioned predetermined characteristics are common or not, together with the above-mentioned information. This notification can be, for example, notified as capability information (UE Capability). In this case, the terminal device 111 can perform the above-mentioned capability notification by, for example, responding to an inquiry message (UECapabilityEnquiry) of capability information from the base station device 101 and transmitting a message (UECapabilityInformation) for notifying the capability information to the base station device 101. Further, based on the acquired information, the base station device 101 can perform, for example, setting of the radio resource control (RRC) layer, and can execute setting and control for the terminal device 111 by using, for example, downlink control information (DCI), etc.

[0021] (Device Configuration) Next, the configuration of the base station device 101 and terminal device 111 that perform the above-described processing will be explained. Figure 2 is a diagram showing an example of the hardware configuration of the base station device 101 and terminal device 111. In one example, the base station device 101 and terminal device 111 are configured to include a processor 201, ROM 202, RAM 203, storage device 204, and communication circuit 205. The processor 201 is a computer configured to include one or more processing circuits, such as a general-purpose CPU (Central Processing Unit) or ASIC (Application-Specific Integrated Circuit), and performs the overall processing of the device and the above-described processing by reading and executing programs stored in the ROM 202 and storage device 204. The ROM 202 is a read-only memory that stores information such as programs and various parameters related to the processing performed by the base station device 101 and terminal device 111. The RAM 203 functions as a workspace when the processor 201 executes programs and is a random access memory that stores temporary information. The storage device 204 is configured, for example, by a removable external storage device. The communication circuit 205 is configured to include, for example, a circuit for communicating with other devices. Although one communication circuit 205 is shown in Figure 2, the base station device 101 and the terminal device 111 may have multiple communication circuits. In this embodiment, the terminal device 111 is configured to include multiple antennas, and these multiple antennas may be connected to one communication circuit 205, or one or more of these multiple antennas may be connected to one communication circuit 205 while the other antennas are connected to another communication circuit 205.

[0022] Figure 3 shows an example of the functional configuration of the terminal device 111. The terminal device 111 is composed of, for example, an information notification unit 301 and a processing unit 302. The functions shown in Figure 3 can be realized, for example, by the processor 201 executing a program stored in the ROM 202 or the storage device 204. Note that this is just an example, and some or all of the functions shown in Figure 3 may be realized by dedicated hardware. Also, Figure 3 shows only the functions of the terminal device 111 that are relevant to this embodiment, and the terminal device 111 may naturally have functions other than those shown in Figure 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 allows it to identify at least one of the combinations of antennas that share a predetermined characteristic and the combinations of antennas that do not share a predetermined characteristic, as described above. In addition to this information, the information notification unit 301 may also notify the base station device 101 of information that identifies the predetermined characteristics. For example, the information notification unit 301 may notify the base station device 101 of information that specifies the predetermined characteristics as average delay, delay spread, radio wave arrival direction, etc., and information that allows it to identify at least one of the combinations of antennas that share the predetermined characteristics and the combinations of antennas that do not share the predetermined characteristics. In addition, if it is predetermined which of the multiple types of predetermined characteristics the information notification unit 301 should notify, it does not need to notify the base station device 101 of information indicating the predetermined characteristics. The processing unit 302 receives control and setting instruction information from the base station device 101 and executes setting and control processing based on that instruction information.

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

[0025] The information acquisition unit 401 acquires information from the terminal device 111 that allows it to identify at least one of the combinations of antennas that share a predetermined characteristic and a combination of antennas that do not share a predetermined characteristic, among the multiple antennas that the terminal device 111 has. In addition, if it is not predetermined which of the multiple types of predetermined characteristics the information pertains to, the information acquisition unit 401 may acquire information that specifies which predetermined characteristic the information pertains to, and at least one of the combinations of antennas that share a predetermined characteristic and a combination of antennas that do not share a predetermined characteristic. The setting control unit 402 performs setting and control of the terminal device 111 based on the information acquired by the information acquisition unit 401.

[0026] (Process flow) Next, we will explain an example of the processing flow performed between the base station device 101 and the terminal device 111.

[0027] Figure 5 shows an example of the processing flow for uplink transmit power control when the predetermined characteristic relates to average delay. In this process, first, for example when terminal device 111 becomes connected, base station device 101 sends a message to terminal device 111 to inquire about its capability information (S501). Then, terminal device 111 responds to the message and notifies base station device 101 of its own capability information (S502). At this time, terminal device 111 may notify base station device 101 that the average delay characteristics when radio waves arrive from base station device 101 are common for antennas 121 and 122, and similarly, that the average delay characteristics are common for antennas 123 and 124. If it is predetermined that antennas will be classified based on the average delay characteristics, the notification that the predetermined characteristic relates 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 antenna 121 and antenna 122 are an antenna group that shares predetermined characteristics, and that antenna 123 and antenna 124 are an antenna group that shares predetermined characteristics. Alternatively, the terminal device 111 may notify the base station device 101 that antenna 121 (or antenna 122) and antennas 123 and 124 do not share predetermined characteristics.

[0028] Based on the information received in S502, the base station device 101 performs settings and controls for communication of the terminal device 111. For example, the base station device 101 separately sets the transmit power control for antennas 121 and 122 and for antennas 123 and 124. The base station device 101 sends an RRC reconfiguration message to the terminal device 111, which includes the transmit power settings for each antenna group (S503). In response, the terminal device 111 sends an RRC reconfiguration complete message to the base station device 101 (S504) to complete the settings. Conventional terminal devices cannot notify information that identifies at least one of the antenna groups that share a predetermined characteristic and the antenna groups that do not share a predetermined characteristic, as in S502. For this reason, the base station device 101 applies a single common setting to multiple antennas for such conventional terminal devices, regardless of their arrangement. In contrast, in this embodiment, the base station device 101 can determine, based on information acquired from the terminal device 111, whether a common setting can be used for each of the antennas of the terminal device 111, and perform setting control based on the result of that determination.

[0029] Subsequently, the base station device 101 allocates frequency and time resources for uplink signal transmission to the terminal device (S505), and the terminal device 111 transmits uplink data (physical uplink shared channel PUSCH) using each antenna based on that allocation (S506). The base station device 101 determines whether transmission power control is necessary for each antenna of the terminal device 111 by measuring a predetermined signal, such as the demodulation reference signal (DM-RS), from 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 antennas 121 and 122 is low and that the transmission power should be increased (S507). In this case, the base station device 101 sends an instruction to the terminal device 111 to increase the transmission power of antennas 121 and 122, while keeping the transmission power of antennas 123 and 124 unchanged. For example, base station device 101 may include such instructions in the downlink control information (DCI) that allocates resources for uplink data transmission to terminal device 111 (S508). For example, in S503, information associating identification information ("A" or "B" in Figure 5) assigned to each setting with a transmit power control command may be transmitted to terminal device 111. Upon receiving this instruction, terminal device 111 increases the transmit power of antennas 121 and 122 and uses each antenna to transmit uplink data on the allocated resources (S509).

[0030] When receiving data on the uplink, the base station device 101 also monitors the DM-RS and continuously adjusts the transmission power according to the received power. Here, suppose the base station device 101 determines, for example, that the received power of the DM-RS transmitted from antennas 123 and 124 is high and that the transmission power should be reduced (S510). In this case, the base station device 101 sends an instruction to the terminal device 111 to reduce the transmission power of antennas 123 and 124, while keeping the transmission power of antennas 121 and 122 unchanged. For example, the base station device 101 may include such an instruction in the downlink control information (DCI) that allocates resources for transmitting data on the uplink to the terminal device 111 (S511). When the terminal device 111 receives this instruction, it reduces the transmission power of antennas 123 and 124 and uses each antenna to transmit data on the uplink using the allocated resources (S512).

[0031] In Figure 5, an example is shown where the increase in the transmission power of antennas 121 and 122 and the decrease in the transmission power of antennas 123 and 124 occur at different times; however, these controls may be performed simultaneously. For example, the base station device 101 may include instructions in the DCI to increase the transmission power of antennas 121 and 122 and decrease the transmission power of antennas 123 and 124, and transmit these instructions to the terminal device 111. It is sufficient that the control of antennas 121 and 122 and antennas 123 and 124 be performed independently, and instructions may be given to increase or decrease the transmission power of all of these antennas. However, even in this case, the instructions may be transmitted for each group of antennas that share a predetermined characteristic.

[0032] Through the above process, the transmission power can be appropriately controlled for each antenna, thereby improving communication efficiency.

[0033] Figure 6 shows an example of the setting control process flow for beam reporting when the predetermined characteristic relates to the direction in which radio waves from the base station device 101 reach the terminal device 111. In this process, as in the case of Figure 5, first, the base station device 101 sends a message to the terminal device 111 inquiring about its capability information (S601). Then, the terminal device 111 responds to the message and notifies the base station device 101 of the capability information of its own device (S602). At this time, the terminal device 111 may notify the base station device 101 that the characteristic of the direction in which radio waves from the base station device 101 arrive (Angle of Arrival, AoA) is common for antennas 121 and 122, and similarly, that the AoA characteristic is common for antennas 123 and 124. If it is predetermined that antennas will be classified based on the AoA characteristic, the notification that the predetermined characteristic is a characteristic related to AoA may be omitted.

[0034] Based on the information received in S602, the base station device 101 performs settings and control for communication of the terminal device 111. For example, the base station device 101 sends an RRC reconfiguration message to the terminal device 111 that includes settings for beam control and management for each antenna group (S603). In response, the terminal device 111 sends an RRC reconfiguration complete message to the base station device 101 (S604) to complete the settings. For example, the base station device 101 notifies the terminal device 111 of the settings necessary for beam control and management, such as the settings for channel status information-reference signals (CSI-RS) and the settings for reporting them, for each antenna group that shares predetermined characteristics. In this process as well, conventional terminal devices would apply one common setting to multiple antennas regardless of their arrangement. In contrast, in this embodiment, the base station device 101 can determine, based on the information obtained from the terminal device 111, whether a common setting can be used for each of the antennas owned by the terminal device 111, and perform setting control based on the result of that determination.

[0035] Subsequently, the base station device 101 transmits, for example, a CSI-RS corresponding to the settings for antennas 121 and 122 (S605), and the terminal device 111 measures the CSI-RS using antennas 121 and 122 (S606). The terminal device 111 may choose not to perform measurements using antennas 123 and 124 for this CSI-RS. Furthermore, the base station device 101 transmits, for example, a CSI-RS corresponding to the settings for antennas 123 and 124 (S607), and the terminal device 111 measures the CSI-RS using antennas 123 and 124 (S608). The terminal device 111 may choose not to perform measurements using antennas 121 and 122 for this CSI-RS. Terminal device 111 continuously performs CSI-RS measurements using antennas 121 and 122 based on a first setting for antennas 121 and 122 (S609). Then, if the measurement results satisfy the conditions specified by the reporting settings for antennas 121 and 122 (S610), terminal device 111 notifies base station device 101 of the measurement results (S611). Similarly, terminal device 111 continuously performs CSI-RS measurements using antennas 123 and 124 based on a second setting for antennas 123 and 124 (S612). Then, if the measurement results satisfy the conditions specified by the reporting settings for antennas 123 and 124 (S613), terminal device 111 notifies base station device 101 of the measurement results (S614).

[0036] Based on the notified measurement results, the base station device 101 performs beam control and management as before. This process allows for appropriate beam control and management for each antenna, thereby improving communication efficiency.

[0037] Figure 7 shows an example of the flow of the setting control process for a sounding reference signal when the predetermined characteristic relates to delay spread. In this process, as in Figures 5 and 6, first, the base station device 101 sends a message to the terminal device 111 to inquire about its capability information (S701). Then, the terminal device 111 responds to the message and notifies the base station device 101 of the capability information of its own device (S702). At this time, the terminal device 111 may notify the base station device 101 that the delay spread characteristics when the radio waves transmitted from antennas 121 and 122 reach the base station device 101 are common, and that the delay spread characteristics of antennas 123 and 124 are common. If it is predetermined that antennas will be classified based on delay spread characteristics, the notification that the predetermined characteristic relates to AoA may be omitted.

[0038] Based on the information received in S702, the base station device 101 performs configuration and control for communication of the terminal device 111. For example, the base station device 101 sends an RRC reconfiguration message to the terminal device 111 that includes the setting of the sounding reference signal (SRS) for each antenna group (S703). In response, the terminal device 111 sends an RRC reconfiguration complete message to the base station device 101 (S704) to complete the configuration. For example, the base station device 101 may set the subcarrier spacing (density on the frequency axis of SRS) for transmitting SRS separately for antennas 121 and 122, and for antennas 123 and 124. Subsequently, the terminal device 111 transmits SRS using antennas 121 and 122 based on a first setting of SRS for those antennas, and transmits SRS using antennas 123 and 124 based on a second setting of SRS for those antennas. This makes it possible to suppress the degradation of efficiency that occurs when using common settings between antennas where the conditions of the transmission path are expected to differ significantly. In this process, however, conventional terminal devices would apply a single common setting to multiple antennas regardless of their arrangement. In contrast, in this embodiment, the base station device 101 can determine whether a common setting can be used for each of the antennas of the terminal device 111 based on information obtained from the terminal device 111, and can perform setting control based on the result of that determination.

[0039] Note that the processes shown in Figures 5 to 7 are examples, and processes other than the shown setting and control processes may be executed. Also, although Figures 5 to 7 describe antennas as being classified by average delay, AoA, and delay spread, in reality, these can be determined solely by the antenna arrangement. That is, antennas within a predetermined distance range can be treated as a group with common characteristics, and antennas with distances exceeding the predetermined range can be treated as having different characteristics. Furthermore, the relationship between the distance and position of the antenna arrangement and the presence or absence of commonality of predetermined characteristics can be associated in advance, and at least one of the groups of antennas that should undergo common setting control and the group of antennas that should undergo independent setting control can be notified from the terminal device to the network based on the characteristics used for setting control. For example, in the above example, it was assumed that antennas 121 and 122 have common characteristics, and antennas 123 and 124 have different characteristics from antennas 121 and 122, but antennas 123 and 124 have common characteristics, but are not limited to this. For example, with respect to average delay, antennas 121 and 122 may share the same characteristics, and antennas 123 and 124 may share the same characteristics, while with respect to delay spread, antennas 121 and 124 may share the same characteristics, and antennas 122 and 123 may share the same characteristics. In this way, multiple antennas are classified into antenna groups, each containing one or more antennas, but this classification may vary depending on predetermined characteristics.

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

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

Claims

1. A terminal device, Multiple antennas, A notification means for notifying the network to which the terminal device belongs of information that can identify at least one of the following among the plurality of antennas: a second antenna that shares predetermined characteristics with a first antenna included in the plurality of antennas, and a third antenna that does not share predetermined characteristics with the first antenna. The system includes a receiving means for receiving communication settings to be set for each of the aforementioned multiple antennas, The receiving means receives the same communication settings as the first antenna as the communication settings to be set for the second antenna, and receives the same communication settings as the first antenna as the communication settings to be set for the third antenna, The receiving means receives the communication settings to be set for each of the plurality of antennas as settings for the Radio Resource Control (RRC) layer. A terminal device characterized by the following features.

2. The receiving means further receives downlink control information (DCI). The terminal device according to feature 1.

3. The DCI includes instructions indicating that the transmit power of one or more of the multiple antennas should be reduced. The terminal device according to feature 2.

4. Network node, An acquisition means for acquiring information from a terminal device belonging to a network including the network node, which can identify at least one of the following: a second antenna having predetermined characteristics in common with a first antenna among the multiple antennas, and a third antenna having predetermined characteristics in common with the first antenna. Based on the aforementioned information, the terminal device has control means for controlling the communication settings to be set for each of the plurality of antennas, The control means controls the second antenna to be set to the same communication settings as the first antenna, and controls the third antenna to be set to the same communication settings as the first antenna, The control means transmits the communication settings to be set for each of the plurality of antennas to the terminal device as settings for the Radio Resource Control (RRC) layer. A network node characterized by the following features.

5. The control means further transmits downlink control information (DCI) to the terminal device. The network node according to feature 4.

6. The DCI includes instructions indicating that the transmit power of one or more of the multiple antennas should be reduced. The network node according to feature 5.

7. A control method performed by a terminal device having multiple antennas, To notify the network to which the terminal device belongs of information that allows for the identification of at least one of the following among the plurality of antennas: a second antenna that shares predetermined characteristics with a first antenna included in the plurality of antennas, and a third antenna that does not share predetermined characteristics with the first antenna. This includes receiving the communication settings to be set for each of the aforementioned multiple antennas, The aforementioned reception means receiving the same communication settings as the first antenna as the communication settings to be set on the second antenna, and receiving the same communication settings as the first antenna as the communication settings to be set on the third antenna, The communication settings to be configured for each of the aforementioned antennas are received as settings for the Radio Resource Control (RRC) layer. A control method characterized by the following:

8. A control method performed by a network node, From a terminal device belonging to the network including the network node, information is obtained that allows for the identification of at least one of the following: a second antenna having predetermined characteristics in common with a first antenna among the multiple antennas, and a third antenna having predetermined characteristics in common with the first antenna. Based on the aforementioned information, the control of communication of the terminal device includes controlling the communication settings to be set for each of the plurality of antennas, Performing the aforementioned control involves controlling the second antenna to use the same communication settings as the first antenna, and controlling the third antenna to use communication settings that are at least partially different from those of the first antenna. The communication settings to be configured for each of the aforementioned antennas are received as settings for the Radio Resource Control (RRC) layer. A control method characterized by including

9. A program for causing a computer to function as a terminal device according to any one of claims 1 to 3.

10. A program for causing a computer to function as a network node according to any one of claims 4 to 6.

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