Terminal device, base station device, control method, and program for suppressing interference effects on communications in adjacent frequency bands

Abstract

To provide a terminal device, a base station device, and a program that sufficiently suppress an influence of interference on adjacent frequency bands in a cellular communication system that flexibly operates radio resources.SOLUTION: A terminal device 102 acquires, from a first base station device 101 belonging to a first communication system using a first frequency band, setting information indicating a measurement setting in a second frequency band, which is different from the first frequency band and used in a second communication system, S501, measures a predetermined signal transmitted from a second base station device 111 belonging to the second communication system on the basis of the setting information S504, notifies the first base station device 101 of a measurement result S506, and communicates with the first base station device 101 according to scheduling performed by the first base station device 101 on the basis of, the measurement result S509.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a technique for suppressing the effects of interference on communications in adjacent frequency bands. [Background technology]

[0002] In a cellular communication system, a downlink signal in a direction from a base station device to a terminal device and an uplink signal in a direction from the terminal device to a base station device are generally separated in time or frequency band to prevent mutual interference between the signals. Such a method can sufficiently suppress interference in communication by a single telecommunications carrier. Also, in communication by multiple telecommunications carriers, interference can be sufficiently suppressed by separating the uplink and downlink in a similar manner and providing a sufficient guard band between adjacent frequency bands. Summary of the Invention [Problem to be solved by the invention]

[0003] Wireless communication is now used for various purposes, and flexible operation is now required in cellular communication systems. In such a situation, interference that did not occur in the past may occur. For example, a situation may be assumed in which an uplink signal is transmitted in a frequency band adjacent to a frequency band in which a downlink signal is transmitted in a first communication carrier. In such a situation, since the distance between the terminal devices may be very close, even if a guard band is provided, the out-of-band components of the uplink signal of the second communication carrier may be received sufficiently strongly in the terminal device of the first communication carrier, and may interfere with the downlink signal. In particular, since the terminal device may be configured to collectively receive signals of a certain frequency band including the frequency bands of multiple communication carriers, the components of the uplink signal of the second communication carrier may become dominant in terms of power among the signals received in the terminal device of the first communication carrier, and the downlink signal addressed to the terminal device may be buried. [Means for solving the problem]

[0004] The present invention provides a method for sufficiently suppressing the effect of interference on adjacent frequency bands in a cellular communication system that flexibly operates radio resources.

[0005] A terminal device according to one aspect of the present invention includes an acquisition means for acquiring, from a first base station device belonging to a first communication system using a first frequency band, configuration information indicating a measurement configuration in a second frequency band different from the first frequency band and used in a second communication system, a measurement means for measuring a predetermined signal transmitted from a second base station device belonging to the second communication system based on the configuration information, a notification means for notifying the first base station device of a result of the measurement, and a communication means for communicating with the first base station device in accordance with a scheduling performed by the first base station device based on the result of the measurement. The acquisition means further acquires information indicating a condition for notifying the first base station device of the result of the measurement, the condition including that the predetermined signal is detected at a power equal to or less than a predetermined power, and the notification means notifies the first base station device of the result of the measurement when the condition is satisfied. do.

[0006] A base station device according to another aspect of the present invention is a base station device belonging to a first communication system using a first frequency band, and includes: a notification means for notifying a terminal device of setting information indicating a setting of measurement in a second frequency band that is different from the first frequency band and is used in a second communication system; a receiving means for receiving a result of measurement of a predetermined signal transmitted from another base station device belonging to the second communication system, performed in the terminal device based on the setting information; and a scheduling means for determining, based on the result of the measurement, whether or not to allow the terminal device to transmit a signal using a predetermined frequency resource included in the first frequency band in a predetermined time resource, and for scheduling communication with the terminal device based on the determination. The notification means further notifies information indicating a condition for the terminal device to notify the base station device of the result of the measurement, the condition including that the predetermined signal is detected at a power level equal to or lower than a predetermined power level. do. Effect of the Invention

[0007] According to the present invention, in a cellular communication system that flexibly manages radio resources, it is possible to sufficiently suppress the influence of interference on adjacent frequency bands. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram illustrating an example of a communication environment. [Diagram 2] FIG. 2 is a diagram illustrating an example of the hardware configuration of a base station device and a terminal device. [Diagram 3] FIG. 2 is a diagram illustrating an example of a functional configuration of a terminal device. [Figure 4] FIG. 2 is a diagram illustrating an example of a functional configuration of a base station device. [Diagram 5] FIG. 11 is a diagram illustrating an example of the flow of processing to be executed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, the 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 features described in the embodiments are essential to the invention. Two or more features among the multiple features described in the embodiments may be arbitrarily combined. In addition, the same reference numbers are used for the same or similar configurations, and duplicated descriptions are omitted.

[0010] (Communication environment) FIG. 1 shows an example of a communication environment considered in this embodiment. In the environment of FIG. 1, for example, there are a plurality of wireless communication systems conforming to the fifth generation (5G) cellular wireless communication standard defined by the 3rd Generation Partnership Project (3GPP). In this environment, for example, a first base station device 101 and a first terminal device 102 belonging to a first wireless communication system provided by a first telecommunications carrier, and a second base station device 111 and a second terminal device 112 belonging to a second wireless communication system provided by a second telecommunications carrier different from the first telecommunications carrier are assumed to exist. Note that this is only an example, and a wireless communication system operating according to another standard may be used, and three or more wireless communication systems may exist. Also, in FIG. 1, only one base station device and one terminal device belonging to each wireless communication system are shown, but naturally there may be more base station devices and terminal devices than this. Note that here, an example is shown in which there are two wireless communication systems provided by two telecommunications carriers, respectively, but for example, at least one wireless communication system may be a local 5G system provided by an operating entity different from the telecommunications carrier. In other words, as long as the operating entities are different, the wireless communication system does not need to be provided by a communications carrier.

[0011] In this embodiment, a first frequency band is used in the first wireless communication system, and a second frequency band different from the first frequency band is used in the second wireless communication system. In one example, the first frequency band and the second frequency band are adjacent frequency bands, but they may be frequency bands that are not adjacent to each other. For example, the first terminal device 102 and the second terminal device 112 both receive signals of a frequency band including both the first frequency band and the second frequency band at once, and perform processing such as Fourier transform on the received signals to extract signals addressed to the own devices. At this time, for example, the second terminal device 112 may perform Fourier transform based on the reception timing of the signal from the second base station device 111.

[0012] Here, it is assumed that frame synchronization is established in the first wireless communication system and the second wireless communication system, and that the timing of the uplink and the downlink coincides. In this case, even if the second terminal device 112 receives a signal from the first base station device 101, the signal is synchronized with the signal from the second base station device 111, and therefore the orthogonality of the signal is guaranteed, so that the interference from the first base station device 101 can be ignored. On the other hand, there is a demand for improving the degree of freedom of the wireless communication system in order to meet various wireless communication needs. For this reason, for example, it is assumed that the timing of the uplink and the downlink is independently determined in each wireless communication system. In this case, the signal from the first terminal device 102 arrives in parallel with the signal from the second base station device 101 in the second terminal device 112. In this case, for example, the first terminal device 102 transmits a signal earlier than the reference timing of the frame so that the signal arrives at the first base station device 101 at a predetermined timing, so that the frame timing of the signal does not match that of the signal from the second base station device 111, and orthogonality is not guaranteed at the time of Fourier transform in the second terminal device 112, which may result in a non-negligible level of interference. In particular, when the first terminal device 102 and the second terminal device 112 are located close to each other, the signal from the first terminal device 102 may be received at the second terminal device 112 with very large power. However, when the second terminal device 112 can receive the signal from the second base station device 111 with sufficient power, the influence of the signal from the first terminal device 102 can be relatively reduced.

[0013] In this embodiment, in consideration of such circumstances, the first terminal device 102 is enabled to detect a signal of the second wireless communication system. Then, when the signal of the second wireless communication system is detected with a sufficiently large power in the first terminal device 102, it is assumed that the signal of the second wireless communication system can be received with sufficient strength in a terminal device of the second wireless communication system (for example, the second terminal device 112) existing around the first terminal device 102. Therefore, in such a situation, even if the first terminal device 102 transmits a signal, it is assumed that the influence of the signal on the second wireless communication system is sufficiently small. Therefore, when the first terminal device 102 transmits a signal, it may be determined that there is no need to perform control to reduce the influence of interference. On the other hand, when the signal of the second wireless communication system is detected with a power equal to or less than a predetermined power in the first terminal device 102, it is expected that the reception strength of the signal of the second wireless communication system is relatively low in a terminal device of the second wireless communication system (for example, the second terminal device 112) existing around the first terminal device 102. For this reason, when the first terminal device 102 transmits a signal, it is expected that the signal will have a large effect on the second wireless communication system. For this reason, it may be determined that control is required to reduce the effect of interference when the first terminal device 102 transmits a signal. Note that, when a signal of the second wireless communication system is not detected, it may be treated in the same way as when the received power of the signal is equal to or lower than a predetermined power, but it may also be treated as if the second wireless communication system does not exist, and it may be determined that there is no effect of the signal transmitted by the first terminal device 102.

[0014] In this way, the first terminal device 102 is enabled to measure radio signals transmitted and received in a wireless communication system different from the wireless communication system to which the first terminal device belongs, and whether or not to reduce interference caused by a signal transmitted from the first terminal device 102 is controlled based on the measurement result. The control to reduce interference may include, for example, control to prevent the first terminal device 102 from transmitting an uplink signal during a period in which downlink communication is performed in the second wireless communication system. Furthermore, the control to reduce interference may, for example, be configured to transmit an uplink signal by the first terminal device 102 using a frequency resource that is sufficiently separated in the frequency domain from the second frequency band of the second wireless communication system during a period in which downlink communication is performed in the second wireless communication system. That is, when the received power of a signal of the second wireless communication system is insufficient around the first terminal device 102, scheduling may be performed such that the power leaking into the frequency resource from which the downlink signal can be transmitted in the second wireless communication system is eliminated or sufficiently reduced. Scheduling may be performed, for example, by adjusting time resources and frequency resources so that the power of signal components leaking into frequency resources in the second wireless communication system, from which downlink signals may be transmitted, is kept below a predetermined value. Scheduling may be performed in the second wireless communication system, rather than in the first wireless communication system. For example, scheduling may be performed in the second wireless communication system so that wireless resources that cause interference at a power level above a certain level when the first terminal device 102 transmits a signal are not used for downlink communication in the second wireless communication system.

[0015] In this embodiment, in order to perform the above-mentioned control, for example, the first base station device 101 notifies the first terminal device 102 of the setting information related to the measurement of the second wireless communication system by a radio resource control (RRC) message when the first terminal device 102 connects to the first base station device 101. That is, the first base station device 101 notifies the first terminal device 102 of the setting information for the measurement of the frequency band used in the second wireless communication system by using an information element (IE) in the RRC message. The first terminal device 102 analyzes the RRC message and obtains the measurement setting information from the IE including the information for the measurement of the other wireless communication system. Note that the notification of the setting information using the RRC message is one example, and the setting information may be notified not only to the terminal device in the connected state but also to the terminal device in the unconnected state by using a broadcast signal, for example.

[0016] When the configuration information is notified using an RRC message, for example, the configuration information may be notified by at least one of MeasObjectNR, MeasObjectCLI, and MeasReport of the RRC message. In addition, a new IE may be defined that is included in the RRC message to notify the configuration information of the measurement of another wireless communication system (for example, a wireless communication system provided by another communication carrier).

[0017] Here, the setting information may include, for example, information indicating a frequency band in which the measurement is to be performed. Here, the information on the frequency band may include, for example, information on a second frequency band used in the second wireless communication system. The information indicating the frequency band in which the measurement is to be performed may be any information capable of identifying the frequency band, such as information indicating the upper and lower end frequencies of the frequency band, or an index previously assigned to the frequency band. The setting information may also include, for example, information indicating a specific frequency to be measured in particular among the frequency band in which the measurement is to be performed, such as the second frequency band. The information indicating the specific frequency may include, for example, an Absolute Radio-Frequency Channel Number (ARFCN). In one example, the NR-ARFCN in the second wireless communication system may be notified as information indicating the specific frequency. The setting information may also include a bandwidth of a frequency band (for example, the second frequency band) in which the measurement is to be performed. The setting information may also include information indicating a signal to be measured. In one example, the information indicating a signal to be measured may be information indicating the positions of a time resource and a frequency resource in which the signal is transmitted. The position of the time resource may be information that directly specifies the time resource, such as a frame number or time information, or may be information that indirectly specifies the time resource, such as an offset value from a reference frame or time. The position of the time resource may include periodic information. The position of the frequency resource may be information that directly specifies the frequency resource, such as a frequency value or a resource block index, or may be information that indirectly specifies the frequency resource, such as an offset value from a reference frequency (for example, a frequency at the lower end or upper end of a frequency band). When the signal to be observed is frequency hopping, information such as a hopping pattern may be used as information indicating the position of the frequency resource. The setting information may be any one of the above-mentioned information, or may include a combination of two or more of these pieces of information. The setting information may include information other than the above-mentioned information.

[0018] The signal to be measured may be, for example, a predetermined signal that is specified to be periodically transmitted in a predetermined frequency and time resource in the second wireless communication system. The predetermined signal may include, for example, a synchronization signal and a physical broadcast channel block (SSB), or a Non Cell-Defined (NCD)-SSB. The SSB (or Cell-Defined (CD)-SSB) is a signal required for the system. The SSB is periodically transmitted in a specific frequency and time resource to establish downlink time synchronization and provide system information such as a Master Information Block (MIB). The NCD-SSB is not required for the system, but is a signal that can be configured to be periodically transmitted in a specific frequency and time resource like the SSB. In addition, the predetermined signal may be, for example, a predetermined reference signal. As this reference signal, an existing reference signal may be used, or a new reference signal for measurement by a terminal device of another wireless communication system may be defined. In addition, when a predetermined signal to be measured is determined in advance, the first base station device 101 does not need to notify the first terminal device 102 of information indicating the signal to be measured.

[0019] The first base station device 101 may notify the first terminal device 102 of information that enables identification of the frequency and time resource at which the predetermined signal is transmitted. The first base station device 101 may acquire the information on the frequency and time resource at which the predetermined signal is transmitted from the second base station device 111, or may hold the information in advance through, for example, a pre-setting by a communication carrier that provides the first wireless communication system. As information that enables identification of the frequency and time resource at which the predetermined signal is transmitted, the above-mentioned frequency band information, frequency bandwidth information, and frequency information related to the predetermined signal such as ARFCN may be used. That is, the frequency and time resource at which the predetermined signal is transmitted may be determined in advance so as to be identifiable by the frequency band information, frequency bandwidth information, and frequency information such as ARFCN. For example, when the predetermined signal is an SSB and the first terminal device 102 does not acquire the ARFCN information, the first terminal device 102 may perform a search for each frequency band to be measured and detect the SSB.

[0020] The first terminal device 102 measures a predetermined signal (for example, SSB or NCD-SSB) transmitted from the second base station device 111 based on the setting information acquired as described above, and notifies the first base station device 101 of the measurement result. The measurement result may include, for example, information indicating the received power of the predetermined signal. In one example, when the predetermined signal to be measured is a reference signal, the reference signal received power (RSRP) may be used as the measurement result. Also, the SS-RSRP based on the synchronization signal may be used as the measurement result. Also, a difference value between the RSRP and a predetermined value (for example, a measurement value of RSRP previously reported or a measurement value of another RSRP reported together) may be notified. Also, as the measurement result, for example, information on a frequency such as ARFCN in a frequency band in which a predetermined signal is detected at or below a predetermined power (or above a predetermined power) may be notified. Also, other information capable of identifying a frequency band in which a predetermined signal is detected at or below a predetermined power (or above a predetermined power) may be notified as the measurement result.

[0021] A condition (event) for this notification may be set. When the condition for notification is satisfied, the first terminal device 102 may notify the first base station device 101 of the measurement result. The first terminal device 102 may, for example, periodically notify. The condition for notification may include, for example, that a predetermined signal of the second wireless communication system is detected at a predetermined power or less. That is, the first terminal device 102 may notify the first base station device 101 of the measurement result under the condition that the situation is such that interference of a predetermined level or more may be caused when the first terminal device 102 transmits a signal. The condition for notification may also include, for example, that a predetermined signal of the second wireless communication system is detected at a power exceeding a predetermined power. That is, the first terminal device 102 may notify the first base station device 101 of the measurement result under the condition that the interference level caused by the signal transmitted by the first terminal device 102 is sufficiently lower than the received power of the signal from the second base station device 111. The condition for notification may include expiration of a predetermined timer that is started by notification of the setting information for measurement. That is, the first terminal device 102 may notify the first base station device 101 of the result of the measurement in response to the passage of a certain time after the acquisition of the setting information. The condition for notification may be notified from the first base station device 101 to the first terminal device 102 together with the setting information, for example, or may be set in advance, for example, when the first terminal device 102 is manufactured. The condition for notification may be one or more of the above-mentioned conditions, or may include conditions other than the above-mentioned conditions.

[0022] When the first base station device 101 receives a report of the result of the measurement from the first terminal device 102, the first base station device 101 executes scheduling of communication with the first terminal device 102 based on the result of the measurement. For example, the first base station device 101 determines whether or not to allow the first terminal device 102 to transmit a signal using a predetermined frequency resource included in the first frequency band used in the first wireless communication system in a predetermined time resource in which the second base station device 111 transmits a signal. That is, the first base station device 101 may determine whether or not to allocate to the first terminal device 102 a predetermined frequency resource that may cause interference with communication in the second frequency band when the first terminal device 102 transmits a signal, based on the result of the measurement. For example, when the first terminal device 102 detects a predetermined signal in the second frequency band with a power equal to or lower than a predetermined power, the first base station device 101 may determine that the predetermined frequency resource should not be allocated to the first terminal device 102 in the above-mentioned predetermined time resource. In this case, the first base station device 101 may, for example, allocate a frequency resource different from the predetermined frequency resource to the signal transmission of the first terminal device 102 in a predetermined time resource, or may not allow the signal transmission of the first terminal device 102 during the predetermined time resource. Also, the first base station device 101 may transmit a downlink signal to the first terminal device 102 in the predetermined time resource. In this way, the first base station device 101 performs scheduling so that the influence of interference on the second wireless communication system caused by the signal transmission of the first terminal device 102 is sufficiently small, and communicates with the first terminal device 102 according to the scheduling. Note that this is just one example, and the first base station device 101 may, for example, notify the second base station device 111 of the measurement result and not allow the second base station device 102 to transmit a signal in the predetermined time resource.

[0023] As described above, in this embodiment, the first terminal device 102 is enabled to measure downlink signals in the second wireless communication system, and the first terminal device 102 is scheduled based on the measurement results. This makes it possible to suppress the influence of signal transmission from the first terminal device 102 on communication (especially downlink communication) in the second wireless communication system.

[0024] (Device configuration) A hardware configuration example of the first base station device 101 and the first terminal device 102 will be described with reference to FIG. 2. In one example, the first base station device 101 and the first terminal device 102 are configured to 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 configured to include one or more processing circuits such as a general-purpose CPU (Central Processing Unit) or an ASIC (Application Specific Integrated Circuit), and executes the overall processing of the device and each of the above-mentioned processes by reading and executing a program stored in the ROM 202 or the storage device 204. The ROM 202 is a read-only memory that stores information such as programs and various parameters related to the processing executed by the first base station device 101 and the first terminal device 102. 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, for example, configured by a removable external storage device. The communication circuit 205 is configured by, for example, a circuit for wireless communication of LTE or 5G. Although one communication circuit 305 is illustrated in FIG. 2, the first base station device 101 and the first terminal device 102 may have a plurality of communication circuits. For example, the first base station device 101 and the first terminal device 102 may have a common antenna for wireless communication circuits for LTE and 5G. The first base station device 101 and the first terminal device 102 may have an antenna for LTE and an antenna for 5G separately. The first base station device 101 may have a communication circuit for wired communication for communication with, for example, other base station devices or network nodes, and the first terminal device 102 may have a communication circuit for other wireless communication systems such as wireless LAN. The first base station device 101 and the first terminal device 102 may have separate communication circuits 205 for each of a plurality of available frequency bands, or may have a common communication circuit 205 for at least a part of those frequency bands.

[0025] 3 is a diagram showing an example of a functional configuration of the first terminal device 102. The first terminal device 102 includes, as its functions, a setting information acquisition unit 301, a measurement unit 302, a measurement result notification unit 303, and a communication control unit 304. These functional units can be realized, for example, by the processor 201 executing a program stored in the ROM 202 or the storage device 204. Since the processing to be executed by the first terminal device 102 has been described above, the functional configuration of the first terminal device 102 will be roughly outlined here and the details will not be repeated.

[0026] The setting information acquisition unit 301 acquires, from the first base station device 101, setting information for measuring a signal transmitted from a second base station device 111 of a second wireless communication system different from the first wireless communication system to which the first terminal device 102 belongs. As described above, this setting information is information for enabling the first terminal device 102 to measure a predetermined signal periodically transmitted from the second base station device 111 at a predetermined frequency and time resource. In addition, in the case where the first terminal device 102 holds information of the predetermined signal transmitted from the second base station device 111 in advance or where the predetermined signal can be detected without specific information, for example, only information indicating that a signal of another system should be measured may be acquired as the setting information. The setting information acquisition unit 301 may acquire information indicating a condition for notifying a measurement result together with the setting information. In addition, the information indicating the condition may be notified as one element of the setting information. The measurement unit 302 measures a predetermined signal (for example, SSB or NCD-SSB) transmitted from the second base station device 111 based on the setting information acquired by the setting information acquisition unit 301. The measurement unit 302 measures, for example, the received power level of a predetermined signal. The measurement result notifying unit 303 notifies the first base station device 101 of the result of the measurement by the measurement unit 302. If a condition for notifying the result of the measurement is set, the measurement result notifying unit 303 notifies the first base station device 101 of the result of the measurement when the condition is satisfied. The communication control unit 304 controls communication with the first base station device 101 in accordance with the scheduling performed by the first base station device 101 based on the result of the measurement.

[0027] 4 is a diagram showing an example of a functional configuration of the first base station device 101. The first base station device 101 includes, as its functions, a setting information notification unit 401, a measurement result receiving unit 402, and a scheduling unit 403. These functional units can be realized, for example, by the processor 201 executing a program stored in the ROM 202 or the storage device 204. Since the processing to be executed by the first base station device 101 has been described above, the functional configuration of the first base station device 101 will be roughly outlined here, and the details will not be repeated.

[0028] The setting information notification unit 401 notifies the first terminal device 102 of setting information for the first terminal device 102 to measure a signal transmitted from a second base station device 111 of a second wireless communication system different from the first wireless communication system to which the first base station device 101 belongs. As described above, this setting information is information for enabling the first terminal device 102 to measure a predetermined signal periodically transmitted from the second base station device 111 at a predetermined frequency and time resource. In addition, in the case where the first terminal device 102 holds information of the predetermined signal transmitted from the second base station device 111 in advance or where the predetermined signal can be detected without specific information, for example, only information indicating that a signal of another system should be measured may be notified as the setting information. In addition, the setting information notification unit 401 may acquire information indicating a condition for notifying the measurement result together with the setting information. In addition, the information indicating the condition may be notified as one element of the setting information. The measurement result receiving unit 402 receives from the first terminal device 102 the result of the measurement of the signal from the second base station device 111 performed by the first terminal device 102 based on the notified setting information. The scheduling unit 403 estimates the influence of the signal transmitted from the first terminal device 102 on the communication of the second wireless communication system based on the measurement result. Then, the scheduling unit 403 determines whether or not it is permissible to allocate to the signal transmission of the first terminal device 101 a radio resource that may cause a predetermined level of interference to the second frequency band when the first terminal device 102 transmits a signal in a predetermined time resource in which the second base station device 111 transmits a signal. The scheduling unit 403 performs scheduling for the communication of the first terminal device 102 based on the determination result. Note that these are merely examples, and the first base station device 101 may negotiate with the second base station device 111 so that, during a period in which the first terminal device 102 transmits a signal, the second base station device 111 does not transmit a signal in a frequency resource that is affected to a predetermined level by the transmission signal of the first terminal device 102. That is, there are various variations in the method of using the measurement result, and the scheduling unit 403 may schedule the communication of the first terminal device 102 in the same manner as in the normal procedure.

[0029] (Processing flow) Next, an example of the flow of processing executed in the first base station device 101 and the first terminal device 102 belonging to the first wireless communication system will be described with reference to Fig. 5. Note that the processing executed by the first base station device 101 and the first terminal device 102 is as described above, so only the flow of processing will be outlined here, and the details will not be repeated.

[0030] First, the first base station device 101 transmits an instruction to the first terminal device 102 to observe a predetermined downlink signal to be transmitted in a second wireless communication system to which the first base station device 101 and the first terminal device 102 do not belong (and to which the first terminal device 102 is assumed not to be connected). At this time, the first base station device 101 transmits setting information enabling measurement to the first terminal device 102 (S501). Note that the first base station device 101 may transmit this instruction and setting information by an RRC message when the first terminal device 102 executes a connection process, so that the measurement is performed by the first terminal device 102 in a connected state. However, this is only one example, and the first terminal device 102 may be configured to observe a downlink signal of the second wireless communication system in a terminal device in an RRC_Idle state, store it as a log, and notify the log when the first terminal device 102 becomes connected. In this case, the first base station device 101 may notify the first terminal device 102 of the setting information for acquiring a log while the first terminal device 102 is in a connected state, or may notify the setting information by system information so that the first terminal device 102 in an RRC_Idle state can acquire the setting information. The terminal device 102 holds the setting information notified in S501, and makes it possible to perform measurements based on the setting information (S502).

[0031] After that, a predetermined signal is transmitted from the second base station device 111 belonging to the second wireless communication system (S503), and the first terminal device 102 measures the predetermined signal using the setting information (S504). Note that the predetermined signal here is assumed to be SSB or NCD-SSB, but a signal other than these may be used as the predetermined signal. The first terminal device 102 reports the result of the measurement in S504 to the first base station device 101 (S506). Note that, for example, if the first terminal device 102 acquires a condition for notifying the result of the measurement in S501, or if such a condition is set in advance by, for example, a standard, etc., the first terminal device 102 can report the measurement result after confirming that the condition is satisfied (S505) (S506).

[0032] Upon receiving the measurement result, the first base station device 101 performs scheduling for the communication of the first terminal device 102 based on the measurement result, and determines resources to be allocated to the communication of the first terminal device 102 (S507). Note that, when a notification condition of the measurement result is set, for example, if the measurement result is not notified, the first base station device 101 may determine that the condition is not satisfied (for example, a predetermined signal of the second wireless communication system with a predetermined power or less was not detected in the first terminal device 102), and perform scheduling based on the determination result. The first base station device 101 allocates resources for downlink signal transmission and uplink signal reception to the first terminal device 102 according to the determined scheduling (S508), and performs communication according to the resource allocation (S509).

[0033] In this manner, in this embodiment, the first terminal device 102 is capable of measuring a downlink signal in a second wireless communication system to which the first terminal device does not belong (is not expected to be connected) and notifying the first base station device 101 (network of the first wireless communication system) of the measurement result. Then, the first wireless communication network determines resource allocation for the communication (particularly the uplink) of the first terminal device 102, taking into consideration the influence of interference caused by the signal transmitted by the first terminal device 102 on the signal received by the second terminal device 112 in the second wireless communication system. This makes it possible to flexibly operate the cellular communication system while suppressing the influence on the communication in other wireless communication systems using adjacent frequency bands, for example, and thus contribute to Goal 9 of the United Nations-led Sustainable Development Goals (SDGs) "Build resilient infrastructure, promote sustainable industrialization and foster innovation."

[0034] The invention is not limited to the above-described embodiment, and various modifications and variations are possible within the scope of the gist of the invention.

Claims

1. an acquisition means for acquiring, from a first base station device belonging to a first communication system using a first frequency band, setting information indicating a measurement setting in a second frequency band different from the first frequency band and used in a second communication system; a measurement means for measuring a predetermined signal transmitted from a second base station device belonging to the second communication system based on the setting information; a notification means for notifying the first base station device of a result of the measurement; a communication means for communicating with the first base station device according to a scheduling performed by the first base station device based on a result of the measurement; having the acquiring means further acquires information indicating a condition for notifying the first base station device of the result of the measurement, the condition including that the predetermined signal is detected at a power level equal to or lower than a predetermined power level; The terminal device, characterized in that the notification means notifies the first base station device of a result of the measurement when the condition is satisfied.

2. The terminal device according to claim 1 , wherein the acquisition means acquires the setting information from an information element in a Radio Resource Control (RRC) message when connecting to the first base station device.

3. The terminal device according to claim 2 , wherein the information elements include at least one of MeasObjectNR, MeasObjectCLI, and MeasReport.

4. The terminal device according to any one of claims 1 to 3, characterized in that the setting information includes at least one of information indicating the second frequency band, information indicating a predetermined frequency to be measured in the second frequency band, a bandwidth of the second frequency band, and information identifying the predetermined signal.

5. 5. The terminal device according to claim 1, wherein the predetermined signal is a signal that is specified to be periodically transmitted from the second base station device at a predetermined frequency and time resource.

6. The terminal device according to any one of claims 1 to 5, characterized in that the predetermined signal includes a synchronization signal and a physical broadcast channel block (SSB), or a Non Cell-Defined (NCD)-SSB.

7. The terminal device according to any one of claims 1 to 6, characterized in that the notification means notifies the first base station device of at least one of information indicating the received power of the specified signal and information on a frequency related to the specified signal as a result of the measurement.

8. A base station device belonging to a first communication system using a first frequency band, a notification means for notifying a terminal device of setting information indicating a measurement setting in a second frequency band that is different from the first frequency band and is used in a second communication system; a receiving means for receiving a result of a measurement of a predetermined signal transmitted from another base station device belonging to the second communication system, the measurement result being performed by the terminal device based on the setting information; a scheduling means for determining whether or not to permit the terminal device to transmit a signal using a predetermined frequency resource included in the first frequency band in a predetermined time resource based on a result of the measurement, and for scheduling communication with the terminal device based on the determination; having The base station device, characterized in that the notification means further notifies information indicating the conditions for the terminal device to notify the base station device of the results of the measurement, the conditions including that the specified signal was detected at a power equal to or lower than a specified power.

9. 9. The base station device according to claim 8, wherein the notification means notifies the setting information by using an information element in a radio resource control (RRC) message when the terminal device connects to the base station device.

10. The base station apparatus according to claim 9 , wherein the information element includes at least one of MeasObjectNR, MeasObjectCLI, and MeasReport.

11. 11. The base station device according to claim 8, wherein the setting information includes at least any one of information indicating the second frequency band, information indicating a predetermined frequency to be measured in the second frequency band, a bandwidth of the second frequency band, and information identifying the predetermined signal.

12. The base station device according to any one of claims 8 to 11, characterized in that the predetermined signal is a signal that is specified to be periodically transmitted from another base station device belonging to the second communication system at a predetermined frequency and time resource.

13. 13. The base station device according to claim 8, wherein the predetermined signal includes a synchronization signal and a physical broadcast channel block (SSB), or a Non Cell-Defined (NCD)-SSB.

14. 14. The base station device according to claim 8, wherein the result of the measurement includes at least one of information indicating a received power of the predetermined signal and information on a frequency associated with the predetermined signal.

15. A control method executed by a terminal device, comprising: an acquisition step of acquiring, from a first base station device belonging to a first communication system using a first frequency band, configuration information indicating a measurement configuration in a second frequency band different from the first frequency band and used in a second communication system; a measurement step of measuring a predetermined signal transmitted from a second base station device belonging to the second communication system based on the setting information; a notification step of notifying the first base station device of a result of the measurement; a communication step of communicating with the first base station device according to a scheduling performed by the first base station device based on a result of the measurement; Including, In the obtaining step, further obtaining information indicating a condition for notifying the first base station device of the result of the measurement, the condition including that the predetermined signal is detected at a power level equal to or lower than a predetermined power level; A control method, comprising the steps of: notifying said first base station device of said measurement result when said condition is satisfied, in said notification step.

16. A control method executed by a base station device belonging to a first communication system using a first frequency band, comprising: a notification step of notifying a terminal device of setting information indicating a measurement setting in a second frequency band that is different from the first frequency band and is used in a second communication system; a receiving step of receiving a result of a measurement of a predetermined signal transmitted from another base station device belonging to the second communication system, the measurement result being performed by the terminal device based on the setting information; a scheduling step of determining whether or not to allow the terminal device to transmit a signal using a predetermined frequency resource included in the first frequency band in a predetermined time resource based on a result of the measurement, and scheduling communication with the terminal device based on the determination; Including, A control method characterized in that, in the notification step, the terminal device further notifies the base station device of information indicating the conditions for notifying the base station device of the results of the measurement, the information including that the specified signal was detected at a power equal to or lower than a specified power.

17. A program for causing a computer to function as the terminal device according to any one of claims 1 to 7.

18. A program for causing a computer to function as the base station device according to any one of claims 8 to 14.

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