Base station device, terminal device, and wireless communication system

Abstract

Provided is a base station device that transmits a plurality of reference signals to a terminal device and receives measurement results of the plurality of reference signals from the terminal device, the base station device comprising: a control unit that notifies the terminal device of transmission information pertaining to transmission of the plurality of reference signals; and a communication unit that receives, from the terminal device, some or all of measurement results of the plurality of reference signals, the measurement results being transmitted in accordance with a priority order determined by the terminal device on the basis of the transmission information.

Description

Technical Field

[0001] The present invention relates to a base station device, a terminal device, and a wireless communication system. Background Art

[0002] In recent years, various studies on technologies related to energy conservation of base station devices in wireless communication systems have been conducted at international standardization conferences and other events (Non-Patent Document 28). As technologies related to energy conservation of base station devices, technologies for adapting spatial elements and transmission power have been proposed (Non-Patent Document 29). Spatial elements include, for example, components related to the transmission and reception of radio waves, such as wireless transceiver circuits or antennas. The base station device includes multiple wireless transceiver circuits and multiple antennas. The base station device can change the number of spatial elements (e.g., wireless transceiver circuits or antennas) or the transmission output based on, for example, the communication load. Specifically, when the communication load between the base station device and the terminal device decreases, the base station device controls one or more wireless transceiver circuits to a disconnected state, reduces the number of multiple antennas used, and reduces the transmission output of the wireless signal sent to the terminal device. In other words, dynamic adaptation of spatial elements or adaptation of transmission power based on the communication load is achieved. As a result, the power consumption of the base station device is saved while preventing throughput loss. Hereinafter, adaptation of spatial elements and adaptation of transmission output may be referred to as adaptation of transmission parameters.

[0003] The base station device obtains, for example, a channel state information (CSI) report from the terminal device and determines the adaptation of transmission parameters such as spatial elements and transmission output based on the state of the communication load. The base station device then appropriately adapts the transmission parameters and transmits a wireless signal to the terminal device using the adapted number of wireless transceiver circuits or the adapted transmission output. CSI reports are periodically or aperiodically transmitted from the terminal device and include measurement results when receiving the reference signal (CSI-RS) transmitted from the base station device.

[0004] In order to achieve adaptation of spatial elements without delay, the base station device can send multiple types of CSI-RS and obtain multiple types of CSI reports. For example, the base station device sends CSI-RS corresponding to different numbers of antenna ports (for example, 32 antenna ports and 16 antenna ports), and obtains CSI reports corresponding to each of the different numbers of antenna ports. The base station device determines the adaptation of spatial elements based on the content of the CSI report. In addition, for example, the base station device sends CSI-RS corresponding to different transmission outputs and obtains CSI reports corresponding to each of the different transmission outputs. The base station device determines the adaptation of the transmit power based on the content of the CSI report.

[0005] For example, in the case of transmitting multiple types of CSI reports, the terminal device may include multiple types of measurement results in one message and transmit the message to the base station device.

[0006] Citation List

[0007] Non-patent literature

[0008] Non-Patent Document 2: 3GPP TS 36.211 V17.2.0

[0009] Non-Patent Document 3: 3GPP TS 36.212 V17.1.0

[0010] Non-Patent Document 4: 3GPP TS 36.213 V17.3.0

[0011] Non-Patent Document 5: 3GPP TS 36.214 V17.0.0

[0012] Non-Patent Document 6: 3GPP TS 36.300 V17.2.0

[0013] Non-Patent Document 7: 3GPP TS 36.321 V17.2.0

[0014] Non-Patent Document 8: 3GPP TS 36.322 V17.0.0

[0015] Non-Patent Document 9: 3GPP TS 36.323 V17.1.0

[0016] Non-Patent Document 10: 3GPP TS 36.331 V17.2.0

[0017] Non-Patent Document 11: 3GPP TS 37.324 V17.0.0

[0018] Non-Patent Document 12: 3GPP TS 37.340 V17.2.0

[0019] Non-Patent Document 13: 3GPP TS 38.133 V17.7.0

[0020] Non-Patent Document 14: 3GPP TS 38.201 V17.0.0

[0021] Non-Patent Document 15: 3GPP TS 38.202 V17.2.0

[0022] Non-Patent Document 16: 3GPP TS 38.211 V17.3.0

[0023] Non-Patent Document 17: 3GPP TS 38.212 V17.3.0

[0024] Non-Patent Document 18: 3GPP TS 38.213 V17.3.0

[0025] Non-Patent Document 19: 3GPP TS 38.214 V17.3.0

[0026] Non-Patent Document 20: 3GPP TS 38.215 V17.2.0

[0027] Non-Patent Document 21: 3GPP TS 38.300 V17.2.0

[0028] Non-Patent Document 22: 3GPP TS 38.321 V17.2.0

[0029] Non-Patent Document 23: 3GPP TS 38.322 V17.1.0

[0030] Non-Patent Document 24: 3GPP TS 38.323 V17.2.0

[0031] Non-Patent Document 25: 3GPP TS 38.331 V17.2.0

[0032] Non-Patent Document 26: 3GPP TS 38.420 V17.2.0

[0033] Non-Patent Document 27: 3GPP TS 38.423 V17.2.0

[0034] Non-Patent Document 28: RP-223540

[0035] Non-Patent Document 29: 3GPP TR 38.864 V18.0.0 Summary of the Invention

[0036] Problems to be solved by the present invention

[0037] In a CSI report, if multiple types of measurement results are sent in a single message, the message size increases. For example, if radio resources for sending a CSI report are insufficient, the terminal device omits part or all of the CSI report and sends the omitted CSI report to the base station.

[0038] When receiving the omitted CSI report, the base station apparatus may not be able to obtain information for determining the adaptation of transmission parameters (e.g., spatial elements, transmission output, etc.). In this case, since the base station apparatus cannot receive a CSI report of a type required for determination, the base station apparatus cannot perform appropriate adaptation of the transmission parameters.

[0039] That is, when adaptation of transmission parameters is performed, there is no appropriate control method that allows the terminal apparatus to transmit a CSI report corresponding to the transmission parameters desired by the base station apparatus.

[0040] One disclosure provides a base station apparatus, a terminal apparatus, and a wireless communication system that prevents interference in adaptation of transmission parameters due to omission of part of a CSI report.

[0041] Solutions to the Problem

[0042] A base station device that transmits multiple reference signals to a terminal device and receives measurement results of the multiple reference signals from the terminal device, the base station device comprising: a control unit that notifies the terminal device of transmission information related to the transmission of the multiple reference signals; and a communication unit that receives part or all of the measurement results of the multiple reference signals from the terminal device, the measurement results being transmitted according to a priority order determined by the terminal device based on the transmission information.

[0043] Beneficial effects of the present invention

[0044] In one disclosure, interference with adaptation of transmission parameters due to omitted portions of a CSI report may be prevented. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 is a diagram showing a configuration example of the wireless communication system 10 .

[0046] Figure 2 2 is a diagram showing a configuration example of the base station apparatus 200 .

[0047] Figure 3 is a diagram showing a configuration example of the terminal device 100 .

[0048] Figure 4 is a diagram showing an example of a sequence of CSI reports.

[0049] Figure 5 is a diagram showing an example of a sequence of CSI reporting in a periodic method.

[0050] Figure 6 is a diagram showing an example of a sequence of CSI reports in a semi-periodic method.

[0051] Figure 7 is a diagram showing an example of a sequence of CSI reporting in an aperiodic method.

[0052] Figure 8 is a diagram illustrating an example of a priority order determination method according to the first method.

[0053] Figure 9is a diagram illustrating an example of a priority order determination method according to the second method.

[0054] Figure 10 is a diagram showing an example of a parameter z other than the number of antenna ports.

[0055] Figure 11 is a diagram showing examples of other expressions.

[0056] Figure 12 is a diagram showing an example of a table related to parameter z.

[0057] Figure 13 is a diagram illustrating an example of a sequence specifying a method of priority order determination processing.

[0058] Figure 14 1 is a diagram illustrating an example of a sequence specifying a method of performing a preset priority order determination process.

[0059] Figure 15 : is a diagram showing an example of the definition related to the priority order determination processing method.

[0060] Figure 16 is a diagram showing an example of the definition of parameters z and AlfaList.

[0061] Figure 17 is a diagram illustrating an example of definitions related to the configuration of a CSI report.

[0062] Figure 18 is a diagram showing an example of a table related to the order of priority.

[0063] Figure 19 is a diagram showing an example of the definition of the priority order and BetaList.

[0064] Figure 20 is a diagram illustrating an example of definitions related to the configuration of a CSI report.

[0065] Figure 21 is a diagram showing an example of the definition of associatedReportConfigInfoList.

[0066] Figure 22 It is a diagram showing an explanation example of the specification. DETAILED DESCRIPTION

[0067] [First embodiment]

[0068] A first embodiment will be described.

[0069] <Wireless Communication System 10>

[0070] Figure 11 is a diagram showing a configuration example of a wireless communication system 10. The wireless communication system 10 includes a base station device 200 and terminal devices 100-1 to 100-m. The wireless communication system 10 is, for example, a communication system that supports adaptation of space elements.

[0071] Base station apparatus 200 is a device that wirelessly connects to and communicates with terminal apparatuses 100-1 to 100-m, and is, for example, an eNodeB or gNodeB. Base station apparatus 200 may be composed of a single device or multiple devices such as a central unit (CU) and distributed units (DU).

[0072] The terminal devices 100 - 1 to 100 - m (hereinafter sometimes also referred to as the terminal device 100 ) are communication devices that are wirelessly connected to the base station device 200 and transmit and receive data, and are, for example, smartphones or tablet terminals.

[0073] In wireless communication system 10, base station apparatus 200 adapts data transmission parameters (e.g., spatial elements, transmit power, etc.) based on received CSI reports. Base station apparatus 200 controls CSI reports transmitted by terminal apparatus 100. Base station apparatus 200 transmits the CSI-RS measured by terminal apparatus 100. Terminal apparatus 100 receives the CSI-RS, measures the radio signal, includes the measurement results in a CSI report, and transmits the report to base station apparatus 200.

[0074] Upon receiving the CSI report, the base station apparatus 200 determines adaptation of transmission parameters, for example, turning on / off a wireless transceiver circuit or changing a transmission output.

[0075] <Configuration Example of Base Station Apparatus 200>

[0076] Figure 2 2 is a diagram showing a configuration example of the base station apparatus 200. The base station apparatus 200 includes a central processing unit (CPU) 210, a storage section 220, a memory 230, and wireless communication circuits 250-1 to 250-n.

[0077] The storage unit 220 is an auxiliary storage device that stores programs and data, such as a flash memory, a hard disk drive (HDD), or a solid state drive (SSD). The storage unit 220 stores a wireless communication control program 221 and a CSI report control program 222.

[0078] The memory 230 is an area for loading programs stored in the storage unit 220. The memory 230 can also be used as an area for storing data of the program.

[0079] Wireless communication circuits 250-1 to 250-n (hereinafter referred to as wireless communication circuits 250) are devices that perform wireless communication with terminal devices 100. Base station device 200 transmits and receives signals (messages) to and from terminal devices 100 via wireless communication circuits 250. Wireless communication circuits 250 are, for example, wireless transceiver circuits and have antenna ports. Base station device 200 controls the number of antenna ports used for communication by turning wireless communication circuits 250 on and off.

[0080] The CPU 210 is a processing unit that loads a program stored in the storage unit 220 into the memory 230 , executes the loaded program, constructs each unit, and executes each process.

[0081] The CPU 210 executes wireless communication control processing to implement a communication unit by executing the wireless communication control program 221. The wireless communication control processing is processing for controlling transmission output and wireless communication with the terminal device 100. In the wireless communication control processing, the base station device 200 establishes a wireless connection with the terminal device 100 and transmits and receives signals (messages).

[0082] The CPU 210 executes the CSI report control program 222 to construct a control unit and perform CSI report control processing. The CSI report control processing instructs the terminal apparatus 100 to transmit a CSI report, transmit a CSI-RS, and receive a CSI report. Furthermore, during the CSI report control processing, the base station apparatus 200 instructs the method for determining a priority order or transmits parameters for determining a priority order when the amount of CSI report data exceeds the amount of radio resources.

[0083] <Configuration Example of Terminal Device 100>

[0084] Figure 3 is a diagram showing a configuration example of the terminal device 100. The terminal device 100 includes a CPU 110, a storage section 120, a memory 130, and a wireless communication circuit 150.

[0085] The storage unit 120 is an auxiliary storage device that stores programs and data, such as a flash memory, an HDD, or an SSD. The storage unit 120 stores a wireless communication program 121 and a CSI reporting program 122 .

[0086] The memory 130 is an area for loading programs stored in the storage unit 120. The memory 130 can also be used as an area for storing data of the program.

[0087] The wireless communication circuit 150 is a device that performs wireless communication with the base station device 200. The terminal device 100 transmits and receives signals (messages) to and from the base station device 200 via the wireless communication circuit 150.

[0088] The CPU 110 is a processing unit that loads the programs stored in the storage unit 120 into the memory 130, executes the loaded programs, constructs each unit, and implements each process.

[0089] The CPU 110 executes wireless communication processing to construct the terminal communication unit by executing the wireless communication program 121. The wireless communication processing is a process of performing wireless communication with the base station device 200. In the wireless communication processing, the terminal device 100 makes a wireless connection with the base station device 200 and transmits and receives signals (messages).

[0090] The CPU 110 executes the CSI report program 122 to construct a processing unit and execute CSI report processing. The CSI report processing is a process of receiving CSI-RS according to an instruction from the base station device 200, measuring the CSI-RS, and transmitting a CSI report. In addition, when the data volume of the CSI report exceeds the radio resources in the CSI report processing, the terminal device 100 determines the priority order and transmits a CSI report in which part or all of the data is omitted.

[0091] <Summary of CSI Report>

[0092] The CSI report is a report including the measurement results when the terminal device 100 receives CSI-RS. The base station device 200 requests the terminal device 100 to transmit a CSI report to determine the optimal parameters for transmitting wireless signals (sometimes referred to as downlink transmission hereinafter) to the terminal device. The CSI report includes, for example, the following measurement results (information elements) related to downlink transmission.

[0093] - RI (Rank Indicator)

[0094] - PMI (Precoding Matrix Indicator)

[0095] - CQI (Channel Quality Indicator)

[0096] - LI (Layer Indicator) [[ID=2�]]

[0097] - CRI (CSI-RS Resource Indicator)

[0098] - L1-RSRP (Layer 1 Reference Signal Receiving Power) <00002,27>- L, - SINR (Layer Signal Interference Noise Ratio)

[0100] In the CSI report, the measurement results may change if the number of spatial elements or the transmission output changes. For example, when the number of antenna ports changes, the PMI, RI, CQI, CRI, etc. may change. In addition, when the transmission output changes, the RI, CQI, LI, L1-RSRP, L1-SINE, etc. may also change.

[0101] Figure 4 This is a diagram showing an example of the sequence of CSI reports. For example, Figure 4 the CSI report is sent periodically. The base station device 200 sends a setting message (S1) (e.g., RRC for periodic CSI) to the terminal device 100, which includes the setting (Config) of the CSI report. The terminal device 100 receives the setting message (S1) and stores the setting of the CSI report.

[0102] The base station device 200 sends CSI-RS (S2) to the terminal device 100. The CSI-RS is sent according to the number of types of measurement objects of the CSI report. For example, in the case where 16 antenna ports and 32 antenna ports are measurement objects, the base station device 200 sends two CSI-RS for each measurement. Note that the base station device 200 may also include multiple CSI-RS into one CSI-RS and send the CSI-RS.

[0103] When receiving the CSI-RS (S2), in response to signal reception, the terminal device 100 performs measurement and sends a CSI report (S3) to the base station device 200. The CSI report includes multiple types of CSI reports, such as CSI reports for 16 antenna ports and 32 antenna ports. As Figure 4 shown, the terminal device 100 may include multiple types of CSI reports into one message or one signal and send the message or signal to the base station device 200.

[0104] <Method for Sending and Receiving CSI Reports>

[0105] For example, there are the following three methods for sending and receiving CSI reports. Each method will be described below.

[0106] <1. Periodic CSI Report>

[0107] The periodic CSI report is a method in which the terminal device 100 sends the CSI report periodically. In the following description, this method may sometimes be referred to as the periodic method.

[0108] Figure 5 This is a diagram showing an example of the sequence of CSI reports in the periodic method. The base station device 200 (gNB) sends RRC establishment, RRC configuration, RRC reconfiguration, or RRC resume (S10) including the setting (config) related to the CSI report to the terminal device 100 (UE). The terminal device 100 receives and stores the setting (CSI setting) related to the CSI report. The CSI setting includes, for example, information related to the CSI-RS to be measured and information related to the content of the CSI report to be reported.

[0109] In the CSI reporting of the periodic method, a trigger for triggering transmission in the MAC layer or the PHY layer is not sent (no low layer trigger).

[0110] The base station apparatus 200 transmits a CSI-RS to the terminal apparatus 100 (S11). The base station apparatus 200 transmits one or more types of CSI-RS according to the CSI-RS-related information included in the CSI configuration.

[0111] When receiving the CSI-RS and performing measurements, the terminal apparatus 100 transmits a CSI report to the base station apparatus 200 (S12). The CSI report is transmitted using, for example, the PUCCH. Furthermore, even when multiple measurement results are requested, the CSI report is transmitted in a single message.

[0112] Thereafter, the base station apparatus 200 repeats the transmission of the CSI-RS and the reception of the CSI report at predetermined time intervals (periodically) ( S13 and S14 ).

[0113] <2. Semi-persistent CSI reporting>

[0114] Semi-persistent CSI reporting is a method in which the terminal apparatus 100 periodically transmits a CSI report until receiving an end trigger in response to receiving a start trigger from the base station apparatus 200. In the following description, this method may be referred to as a semi-periodic method.

[0115] Figure 6 This figure shows an example of a sequence for CSI reporting in a semi-periodic method. The base station apparatus 200 transmits an RRC setup, RRC configuration, RRC reconfiguration, or RRC recovery message including settings related to CSI reporting to the terminal apparatus 100 (S20). The terminal apparatus 100 receives and stores the settings related to CSI reporting (CSI settings).

[0116] The base station apparatus 200 transmits a MAC-CE including, for example, an activation indicator as a trigger for starting to transmit CSI reports to the terminal apparatus 100 (S21). Upon receiving this MAC-CE, the terminal apparatus 100 waits for the CSI-RS and begins processing the CSI report. Furthermore, instead of transmitting a MAC-CE, the base station apparatus 200 may transmit DCI scrambled with the SP_CSI_RNTI.

[0117] Note that when using DCI as a trigger to start the semi-periodic method, there are cases where one DCI can support only one CSI report. For example, when triggering the transmission of CSI reports for both 16 antenna ports and 32 antenna ports, base station apparatus 200 may transmit two DCIs: one corresponding to 16 antenna ports and one corresponding to 32 antenna ports.

[0118] The base station apparatus 200 transmits a CSI-RS to the terminal apparatus 100 (S22). The base station apparatus 200 transmits one or more types of CSI-RS according to the CSI-RS related information included in the CSI configuration.

[0119] When the terminal apparatus 100 receives the CSI-RS and performs measurement, it transmits a CSI report to the base station apparatus 200 ( S23 ). For example, the CSI report is transmitted using the PUCCH or the PUSCH.

[0120] Thereafter, the base station apparatus 200 repeats the transmission of the CSI-RS and the reception of the CSI report at predetermined time intervals ( S24 and S25 ).

[0121] Then, the base station apparatus 200 transmits a MAC-CE including a deactivation indicator to the terminal apparatus 100. This deactivation indicator serves as a termination trigger for terminating the periodic transmission of CSI reports (S26). Furthermore, instead of transmitting a MAC-CE, the base station apparatus 200 may transmit DCI scrambled with the SP_CSI_RNTI. Upon receiving the termination trigger, the terminal apparatus 100 terminates its waiting for the CSI-RS and terminates the processing of the CSI report.

[0122] <3. Non-periodic CSI reporting>

[0123] Aperiodic CSI reporting is a method in which the terminal apparatus 100 transmits a CSI report non-periodically (for example, once) in response to receiving an instruction to transmit a CSI report from the base station apparatus 200. In the following description, this method may be referred to as an aperiodic method.

[0124] Figure 7 This figure shows an example of a sequence for CSI reporting in an aperiodic method. The base station apparatus 200 transmits an RRC setup, RRC configuration, RRC reconfiguration, or RRC recovery message including CSI reporting-related settings to the terminal apparatus 100 (S30). The terminal apparatus 100 receives and stores the CSI reporting-related settings (CSI settings).

[0125] The base station apparatus 200 transmits, for example, DCI including a CSI transmission request (CSI request) as a CSI report transmission trigger ( S31 ) to the terminal apparatus 100. Upon receiving the DCI, the terminal apparatus 100 waits for the CSI-RS and performs processing for the CSI report.

[0126] For example, after X (X is an integer) time slots have passed, the base station apparatus 200 transmits CSI-RS to the terminal apparatus 100 (S32). The base station apparatus 200 transmits one or more types of CSI-RS according to CSI-RS related information included in the CSI setting.

[0127] For example, after Y (Y is an integer) time slots have passed, the terminal apparatus 100 receives and measures the CSI-RS and transmits a CSI report to the base station apparatus 200 ( S33 ). The CSI report is transmitted using, for example, the PUSCH.

[0128] When transmission and reception of the CSI report are completed, the base station apparatus 200 and the terminal apparatus 100 end the processing for the CSI report in a series of aperiodic methods.

[0129] <Priority Order Determination Processing>

[0130] As described above, regardless of the method used for CSI reporting, there are cases where multiple types of CSI reports can be sent in a single message. However, depending on the amount of radio resources allocated to terminal device 100, there are cases where it is not possible to send all CSI reports. Therefore, terminal device 100 can determine the priority order of each CSI report during the priority order determination process, and can omit some or all data based on the priority order. The following description explains the priority order determination process.

[0131] <1. First Method>

[0132] The first method is a priority order determination method that does not consider spatial elements. Figure 8 is a diagram illustrating an example of a priority order determination method according to the first method.

[0133] For example, when CSI reports for 16 antenna ports and 32 antenna ports are requested and transmission of CSI reports for both 16 antenna ports and 32 antenna ports is not permitted due to insufficient radio resources, the terminal device 100 uses Expression (1) to determine the priority order. The terminal device 100 then omits transmission of CSI reports for either 16 antenna ports or 32 antenna ports according to the priority order and transmits the CSI report.

[0134] The parameter y indicates the method used for CSI reporting. The aperiodic method using PUSCH is set to 0. The semi-periodic method using PUSCH is set to 1. The semi-periodic method using PUCCH is set to 2. The periodic method using PUSCCH is set to 3.

[0135] The parameter k is an element related to the transmission of the CSI report. For CSI reports that transmit L1-RSRP or L1-SINR, it is set to 0. For CSI reports that do not transmit L1-RSRP or L1-SINR, it is set to 1.

[0136] Parameter c indicates the index of the serving cell.

[0137] Ncells indicates the value of maxNrofServingCells of the RRC parameter. Note that the RRC parameter can be described as an upper layer parameter.

[0138] The parameter s indicates reportConfigID.

[0139] The parameter Ms indicates the value of the maxNrofCSI-ReportConfigurations RRC parameter.

[0140] In Expression 1, the priority order is calculated by multiplying each parameter by a coefficient and then adding the product values. For example, the larger the value, the higher the priority order.

[0141] <2. Second Method>

[0142] The second method is to determine the priority order of spatial elements. Figure 9 : is a diagram showing an example of a priority order determination method according to the second method. In Expression 2 in the second method, a parameter z related to transmission parameters (eg, space elements, transmission output, etc.) is added to the parameters used in Expression 1.

[0143] The parameter z is a parameter related to the number of antenna ports or the transmission output in the CSI-RS transmitted by the base station apparatus 200. In Expression 2, the parameter z is, for example, the number of antenna ports or a value related to the number of antenna ports (the number of CSI-RS antenna ports).

[0144] Figure 10This figure shows examples of parameter z in addition to the number of antenna ports. Parameter z may include, for example, a value related to transmit output (CSI-RS Tx power), an offset between the transmit output of the CSI-RS and the transmit output of the Physical Downlink Shared Channel (PDSCH), an offset between the transmit output of the CSI-RS and the transmit output of the Secondary Synchronization Signal (SSS), and the total value of the number of antenna ports and transmit output (the number of CSI-RS antenna ports and the CSI-RS Tx power).

[0145] In Expression 2, the priority order is calculated by multiplying each parameter by a coefficient and adding the product values. For example, as in Expression 1, the larger the value, the higher the priority order.

[0146] Note that expression 2 is not limited to Figure 9 The expression shown in . Figure 11 is a diagram showing examples of other expressions. Expression 2 can be Figure 11 Any one of Expression 3 to Expression 6 shown. Expression 2 to Expression 6 differ in how the parameter z is used.

[0147] For example, the base station apparatus 200 selects the first method or the second method according to the degree of consideration of the transmission parameters (the degree of consideration of the transmission parameters when determining the priority) and then notifies the terminal apparatus 100 of the selected method.

[0148] For example, when it is desired to measure the influence of transmission parameter changes, base station apparatus 200 selects the second method in consideration of the transmission parameters. Note that base station apparatus 200 may determine the expression for determining priority from part or all of Expressions 1 to 6, for example.

[0149] Figure 12 is a diagram showing an example of a table related to parameter z.

[0150] Figure 12 (A) is a diagram showing the relationship between the number of antenna ports and the parameter z. For example, the larger the number of antenna ports, the smaller the value of the parameter z.

[0151] Figure 12 (B) is a diagram showing the relationship between the transmission output and the parameter z. Figure 12 The transmission output in (B) is, for example, an offset value of the transmission output in CSI-RS compared to SSS. The larger the offset value, the smaller the value of parameter z.

[0152] Figure 12 (C) is a diagram showing the relationship between the transmission output and the parameter z. Figure 12The transmission output in (C) is, for example, an offset value of the transmission output in the CSI-RS compared to the PDSCH. The larger the offset value, the smaller the value of the parameter z.

[0153] Figure 12 (D) is a diagram showing the relationship between the CSI report identifier and parameter z. The CSI report identifier is an ID assigned to each CSI report type. The value of parameter z is set according to the type of CSI report.

[0154] <Method for Designating Priority Determination Processing>

[0155] Base station apparatus 200 instructs terminal apparatus 100 to perform a priority determination process. The instruction content includes, for example, information related to priority determination (hereinafter sometimes referred to as priority order information), such as information related to which priority determination process to use or information related to parameters in the priority determination process.

[0156] Figure 13 : is a diagram illustrating an example of the flow of a method of specifying priority determination processing.

[0157] Step 1 is to set a rule (priority rule) for determining the priority order of CSI reports in terminal device 100. The priority rule includes, for example, part or all of the priority order information. Base station device 200 transmits the priority rule to terminal device 100 using, for example, RRC, DCI, MAC-CE, etc. (S101).

[0158] Step II is a step of indicating the rule (applicable rule) to be applied to the terminal device 100. The applicable rule includes, for example, information indicating which of the plurality of priority order rules is to be effective, such as information indicating which method of the priority order rules is to be used to determine the priority order. The base station device 200 transmits the applicable rule to the terminal device 100 using, for example, RRC, DCI, MAC-CE, etc. (S102). It should be noted that if the applicable rule is specified in step I (when the priority order determination process is uniquely determined by the priority order rule), step II can be omitted.

[0159] Step III is a step in which the terminal device 100 measures the CSI-RS ( S103 ), performs a priority order determination process according to the priority order rule and the applicable rule ( S104 ), and transmits a CSI report ( S105 ).

[0160] Figure 14 : is a diagram showing an example of a sequence of a method for specifying a preset priority order determination process. Figure 14In the sequence, the priority order rule in step I is pre-set in the terminal device 100 (S201). Step II, step III and each message (S202 to S205) are Figure 13 The same as in .

[0161] <Definition of Information Elements>

[0162] Figure 15 This figure shows an example of definitions related to priority determination methods. Priority-rule-r18 indicates which of the first and second methods is selected. Furthermore, for example, if there are three or more priority determination methods, Priority-rule-r18 may also indicate which method is selected.

[0163] Figure 16 This figure shows an example of the definition of the parameter z and AlfaList. Alfa can be, for example, the number of antenna ports in the CSI-RS, the offset of the transmit output in the CSI-RS compared to the SSS, the offset of the transmit output in the CSI-RS compared to the PDSCH, or the ID of the CSI report.

[0164] Figure 17 : is a diagram showing an example of definitions related to the configuration of a CSI report. The definition of parameter z is added to CSI-ReportConfig.

[0165] <Example of Sequence for Specifying Method of Priority Order Determination Processing>

[0166] In the following description, a case where the presetting is performed and a case where the presetting is not performed are described.

[0167] <1. Pre-set situations>

[0168] For example, using Figure 5 A sequence of periodic methods is used to illustrate a pre-set situation.

[0169] The terminal device 100 has a preset priority order rule ( Figure 14 Step I).

[0170] The base station apparatus 200 transmits an RRC establishment, RRC configuration, RRC reconfiguration, or RRC recovery (S10, Figure 14 Step II).

[0171] The applicable rules include, for example, a priority order determination processing method and a parameter z. For example, the base station apparatus 200 uses Figure 15 The definition of notifies the terminal device 100 of the priority order determination method. In addition, the base station device 200 uses, for example, Figure 16 or Figure 17 The definition of notifies the terminal device 100 of the parameter z.

[0172] The terminal device 100 receives the application rule (S10) and stores the application rule. The base station device 200 transmits the CSI-RS to the terminal device 100 (S11, Figure 14 In step III), the base station apparatus 200 transmits, for example, CSI-RS for 16 antenna ports and 32 antenna ports. Furthermore, the base station apparatus 200 transmits, for example, CSI-RS for -6 dB output offset and 0 dB output offset relative to the PDSCH.

[0173] When receiving a CSI-RS and performing measurement, the terminal device 100 creates a CSI report. If all items of the created CSI report cannot be transmitted due to insufficient radio resources, the terminal device 100 performs a priority order determination process. Which priority order determination process is performed depends on the applicable rules.

[0174] The terminal apparatus 100 transmits a CSI report to the base station apparatus 200 (S12). For example, the terminal apparatus 100 omits the CSI reports for 16 antenna ports with a low priority order and transmits a CSI report for only 32 antenna ports to the base station apparatus 200. Furthermore, for example, the terminal apparatus 100 omits the CSI reports for a -3 dB output offset with a low priority order and transmits a CSI report for only a 0 dB output offset to the base station apparatus 200.

[0175] Thereafter, base station apparatus 200 repeats CSI-RS transmission and CSI report reception at predetermined time intervals (S13 and S14). If transmission of all CSI reports is not permitted during periodic transmission of CSI reports, terminal apparatus 100 performs priority determination processing, omits some or all CSI reports, and transmits the omitted CSI reports.

[0176] Note that the same designation method is used in both the semi-periodic and aperiodic methods. In the semi-periodic method, for example, Figure 6 The processing of S20 in corresponds to Figure 5 In addition, in the non-periodic method, for example, Figure 7 The processing of S30 corresponds to Figure 5 Processing of S10 in.

[0177] <2. Cases without pre-set settings>

[0178] Use e.g. Figure 5 The sequence of periodic methods in is used to illustrate the case where there is no pre-set condition.

[0179] The base station apparatus 200 transmits an RRC establishment, RRC configuration, RRC reconfiguration, or RRC recovery including a priority order rule to the terminal apparatus 100 (S10, Figure 13 Step I).

[0180] The priority order rule includes, for example, a priority order determination processing method to be used and a parameter z. In addition, in the case where the terminal device 100 supports only one priority order determination processing method, the priority order determination processing method may be omitted. For example, the base station device 200 uses Figure 15 The definition of notifies the terminal device 100 of the priority order determination method. In addition, the base station device 200 uses, for example, Figure 16 or Figure 17 The definition of notifies the terminal device 100 of the parameter z.

[0181] The terminal device 100 receives the priority order rule (S10) and stores the priority order rule. Figure 13 This is because the designation corresponding to the applicable rule is performed in step I.

[0182] The base station apparatus 200 transmits a CSI-RS to the terminal apparatus 100 (S11, Figure 13 Step III). The base station apparatus 200 transmits, for example, CSI-RS for 16 antenna ports and 32 antenna ports. Furthermore, the terminal apparatus 100 transmits, for example, CSI-RS with a -6dB output offset and a 0dB output offset relative to the PDSCH. The same processing as in the pre-set case is then performed.

[0183] Note that the same designation method is used in both the semi-periodic and aperiodic methods. In the semi-periodic method, for example, Figure 6 The processing of S20 in corresponds to Figure 5 In addition, in the non-periodic method, for example, Figure 7 The processing of S30 corresponds to Figure 5 In this case, step II is omitted as in the periodic method.

[0184] Furthermore, in the semi-periodic method and the aperiodic method, for example, Figure 6 The S20's processing and Figure 7 In the process of S30 of the method, the setting corresponding to the preset setting is sent to the terminal device 100. In this case, the process of step II in the semi-periodic method Figure 6 The process of S21 is performed in the non-periodic method, and the process of S31 is performed in the non-periodic method. For example, the applicable rule is similar to the rule in the case where there is a preset rule.

[0185] Note that when using DCI or MAC_CE to notify rules and parameters, a new DCI format or a new MAC_C format can be defined. In addition, a field can be added to the format of the DCI or MAC_CE. In addition, a new RNTI can be defined and used for notification. DCI and MAC_CE can use DCI or MAC_CE that triggers CSI reporting in a semi-periodic or aperiodic manner, or can use DCI or MAC_CE that instructs base station apparatus 200 to enter a power saving state (i.e., a state in which spatial element adaptation or transmission power adaptation is applied).

[0186] [Second embodiment]

[0187] A second embodiment will be described. In the second embodiment, the base station apparatus 200 directly specifies the priority order instead of the parameter z.

[0188] In the second embodiment, the terminal apparatus 100 does not calculate the priority order through the priority order determination process, but directly uses the priority order acquired from the base station apparatus 200 and omits CSI reporting.

[0189] Figure 18 is a diagram showing an example of a table related to the order of priority.

[0190] Figure 18 (A) is a diagram showing the relationship between the number of antenna ports and the priority order. For example, the greater the number of antenna ports, the smaller the priority order value (the higher the priority order).

[0191] Figure 18 (B) is a diagram showing the relationship between the transmission output and the priority order. Figure 12 The transmission output in (B) is, for example, an offset value of the transmission output compared to SSS. The larger the offset value, the smaller the priority value (the higher the priority).

[0192] Figure 18 (C) is a diagram showing the relationship between the transmission output and the priority order. Figure 12 The transmission output in (C) is, for example, an offset value of the transmission output compared to the PDSCH. The larger the offset value, the smaller the priority value (the higher the priority).

[0193] Figure 18 (D) is a diagram showing the relationship between the CSI report identifier and the priority order. The CSI report identifier is an ID assigned to each type of CSI report. The priority order value is set according to the type of CSI report.

[0194] Figure 19 This figure shows an example of the definition of priority order and BetaList. For example, Beta can be the number of antenna ports in CSI-RS, the offset of the transmit output in CSI-RS compared to SSS, the offset of the transmit output in CSI-RS compared to PDSCH, or the ID of the CSI report.

[0195] Base station apparatus 200 uses Figure 19 The definition shown instead of Figure 16 Definition shown.

[0196] Figure 20 : is a diagram showing an example of definition related to the configuration of CSI report. The definition of priority order is added to CSI-ReportConfig.

[0197] Base station apparatus 200 uses Figure 20 The definition shown instead of Figure 17 Definition shown.

[0198] [Third embodiment]

[0199] For example, in the semi-periodic method, there are cases where a single DCI0_1 cannot trigger multiple CSI reports. In this case, multiple DCI0_1s may be transmitted, and a delay may occur in the transmission of the trigger. As a result, base station apparatus 200 may not receive the CSI report at the appropriate timing. Therefore, the following defines an information element used in the semi-periodic method to trigger the start of each of multiple CSI reports using a single DCI0_1.

[0200] Figure 21 : This is a diagram showing an example of the definition of associatedReportConfigInfoList. For example, instead of configuring a single associatedReportConfigInfo in the semi-periodic method shown above, an associatedReportConfigInfoList obtained by executing a list of associatedReportConfigInfo is defined.

[0201] Figure 22 is a diagram showing an exemplary description of the specification. Figure 22 The limitations in the specification are described, excluding NZP-CSI-RS-Resource-r18. That is, CSI-RS resources belonging to a set defined in NZP-CSI-RS-Resource-r18 can be configured with different numbers of antenna ports.

[0202] [Other embodiments]

[0203] The above embodiments may also be used in combination. For example, the base station apparatus 200 and the terminal apparatus 100 may have a common table for the parameter z and the priority order, and may notify the parameter z and the priority order using an index of the table or the like.

[0204] In addition, the setting of the priority order rule and the setting of the applicable rule may partially overlap, or part of one rule may be set by the other rule. For example, all the contents set by the priority order rule and all the contents set by the applicable rule may be set in any message or in the pre-setting, and all the pieces of information used in the priority order processing method or the priority order calculation using the expression may be set in any rule or in the pre-setting.

[0205] In addition, in a method where a priority order processing method is indicated without pre-setting, for example, the content corresponding to the pre-setting may be notified via a message other than an RRC message. Furthermore, applicable rules may be set in messages other than RRC messages, DCI, or MAC CE. The message names in this embodiment are examples, and the message names and attributes (such as the layer to be managed) are not limited to the messages described in the embodiments.

[0206] Reference Signs List

[0207] 10: Wireless communication system

[0208] 100: Terminal device

[0209] 110: CPU

[0210] 120: Storage

[0211] 121: Wireless Communication Program

[0212] 122: CSI Reporting Procedure

[0213] 130: Memory

[0214] 150: Wireless communication circuit

[0215] 200: Base station device

[0216] 210: CPU

[0217] 220: Storage

[0218] 221: Wireless Communication Control Program

[0219] 222: CSI Reporting Control Procedure

[0220] 230: Memory

[0221] 250: Wireless communication circuit

Claims

1. A base station apparatus that transmits multiple reference signals to a terminal apparatus and receives measurement results of the multiple reference signals from the terminal apparatus, the base station apparatus comprising: a control unit configured to notify the terminal device of transmission information related to transmission of the plurality of reference signals; as well as A communication unit receives part or all of measurement results of the plurality of reference signals from the terminal device, the measurement results being transmitted according to a priority order determined by the terminal device based on the transmission information.

2. The base station apparatus according to claim 1, wherein The transmission information includes information corresponding to the number of antenna ports when each of the plurality of reference signals is transmitted.

3. The base station apparatus according to claim 1, wherein: The transmission information includes information corresponding to a transmission output when each of the plurality of reference signals is transmitted. The base station device according to claim 1 , wherein: The transmission information includes information corresponding to a transmission output when each of the plurality of reference signals is transmitted and the number of antenna ports. The base station device according to claim 1 , wherein: The control section selects one priority order determination method from among a plurality of priority order determination methods, and notifies the terminal device of the selected priority order determination method. The base station apparatus according to claim 5 , wherein: The plurality of priority order determination methods include a method that does not consider the transmission information.

7. A terminal device that receives a plurality of reference signals from a base station device and transmits measurement results of the plurality of reference signals to the base station device, the terminal device comprising: a terminal communication unit configured to receive transmission information related to transmission of the plurality of reference signals from the base station apparatus; as well as A processing unit determines a priority order of each measurement result of the plurality of reference signals based on the transmission information, and transmits part or all of the measurement results of the plurality of reference signals to the base station apparatus.

8. A wireless communication system, comprising: a base station apparatus, the base station apparatus transmitting a plurality of reference signals to a terminal apparatus; and a terminal device that transmits measurement results of the plurality of reference signals, wherein The base station device is configured to transmit transmission information related to transmission of the plurality of reference signals to the terminal device, The terminal device is configured to receive the transmission information, determine the priority order of each measurement result of the multiple reference signals according to the transmission information, and transmit part or all of the measurement results of the multiple reference signals to the base station device.

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