Terminal, communication method, base station, and communication system

Abstract

Provided is a terminal comprising: a reception unit that detects a paging advance notification signal; and a control unit that, on the basis of the paging advance notification signal, determines the advisability of using a reference signal for synchronization at each intermittent reception cycle of one or more intermittent reception cycles.

Description

Terminal

[0001] The present invention relates to a terminal in a wireless communication system.

[0002] In the 3GPP (3rd Generation Partnership Project), a wireless communication method called 5G or NR (New Radio) (hereinafter, this wireless communication method will be referred to as "NR") is being studied in order to realize a larger system capacity, a higher data transmission speed, a lower latency in wireless sections, etc. In NR, various wireless technologies and network architectures are being studied in order to meet the requirement of achieving a throughput of 10 Gbps or more while reducing the latency in wireless sections to 1 ms or less.

[0003] In NR, as in LTE, paging is performed to call a terminal in standby mode when a call is received. In NR, a terminal in an RRC_IDLE state or an RRC_INACTIVE state performs discontinuous reception operation for power saving in order to monitor paging DCI (for example, Non-Patent Document 1). In discontinuous reception operation, the period in which a terminal wakes up from a sleep state and performs paging monitoring is called a PO (paging occasion). Hereinafter, a terminal in an RRC_IDLE state or an RRC_INACTIVE state may be referred to as an idle / inactive mode UE.

[0004] 3GPP TS 38.304 V16.1.0 (2020-07)

[0005] When an idle / inactive mode UE in an existing NR performs paging monitoring at a PO (paging occasion), it is necessary to perform synchronization processing such as time / frequency tracking and AGC (auto gain control) in advance. It is necessary to perform reception processing of multiple SSBs (synchronization signal blocks).

[0006] However, because SSB is transmitted at a relatively long interval, the terminal must wake up earlier than the timing of PO reception to receive multiple SSBs in order to process the SSBs. This makes it impossible to maintain a long sleep period, which leads to increased terminal power consumption.

[0007] It is conceivable that terminal power consumption can be reduced by using TRS / CSI-RS as a synchronization signal, but TRS / CSI-RS cannot always be used as a synchronization signal.

[0008] Therefore, it is being considered to notify an idle / inactive mode UE whether TRS / CSI-RS can be used as a synchronization reference signal. As a signal for notification, Paging early indication (hereinafter referred to as PEI), Paging DCI, SIB, etc. can be considered. However, since the terminal operation for PEI is not clear, there is a problem that it may not be possible to appropriately reduce the power consumption of the terminal.

[0009] The present invention has been made in view of the above points, and has an object to provide a technique that enables appropriate reduction in power consumption of a terminal during paging monitoring.

[0010] According to the disclosed technology, a terminal is provided that includes: a receiving unit that detects a paging advance notification signal; and a control unit that determines whether a synchronization reference signal is available in each of one or more discontinuous reception cycles based on the paging advance notification signal.

[0011] The disclosed technology provides a technology that enables appropriate reduction of power consumption of a terminal during paging monitoring.

[0012] FIG. 1 is a diagram for explaining a wireless communication system in an embodiment of the present invention. FIG. 1 is a diagram for explaining a wireless communication system in an embodiment of the present invention. FIG. 2 is a diagram for explaining an operation example for paging monitoring. FIG. 3 is a diagram for explaining PEI. FIG. 4 is a diagram for explaining an overview of an embodiment. FIG. 5 is a sequence diagram showing a basic operation example. FIG. 6 is a diagram for explaining Example 1-1. FIG. 7 is a diagram for explaining Example 1-2. FIG. 8 is a diagram for explaining Example 1-2. FIG. 9 is a diagram for explaining Example 1-3. FIG. 10 is a diagram for explaining Example 1-3. FIG. 11 is a diagram for explaining Example 1-4. FIG. 12 is a diagram for explaining Example 1-5. FIG. 13 is a diagram for explaining Example 1-6. FIG. 14 is a diagram for explaining Example 1-7.

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the embodiment described below is an example, and the embodiment to which the present invention is applied is not limited to the following embodiment.

[0014] In the operation of the wireless communication system according to the embodiment of the present invention, existing technology is used as appropriate. The existing technology is, for example, existing NR, but is not limited to existing NR.

[0015] Furthermore, this specification uses terms used in existing NR or LTE specifications, such as PDCCH, RRC, MAC, and DCI, but the channel names, protocol names, signal names, function names, etc. used in this specification may be called by other names. Furthermore, although the terminal operation in this embodiment is assumed to be the operation of a terminal in idle / inactive mode, this is an example, and the technology according to the present invention may be applied to a terminal in connected mode.

[0016] (System Configuration) Fig. 1 is a diagram for explaining a wireless communication system according to an embodiment of the present invention. As shown in Fig. 1, the wireless communication system according to the embodiment of the present invention includes a base station 10 and a terminal 20. Although Fig. 1 shows one base station 10 and one terminal 20, this is an example, and there may be a plurality of each.

[0017] The base station 10 is a communication device that provides one or more cells and performs wireless communication with the terminal 20. The physical resources of a wireless signal are defined in the time domain and the frequency domain, and the time domain may be defined by the number of OFDM symbols, and the frequency domain may be defined by the number of subcarriers or the number of resource blocks. Furthermore, a TTI (Transmission Time Interval) in the time domain may be a slot, or a TTI may be a subframe.

[0018] The base station 10 transmits a synchronization signal, system information, and the like to the terminal 20. The synchronization signal is, for example, NR-PSS and NR-SSS. The synchronization signal may also be SSB. The system information is transmitted, for example, via NR-PBCH or PDSCH, and is also referred to as broadcast information. As shown in FIG. 1, the base station 10 transmits control signals or data to the terminal 20 via DL (Downlink) and receives control signals or data from the terminal 20 via UL (Uplink). Note that, here, signals transmitted via control channels such as PUCCH and PDCCH are referred to as control signals, and signals transmitted via shared channels such as PUSCH and PDSCH are referred to as data, but these terms are merely examples.

[0019] The terminal 20 is a communication device equipped with a wireless communication function, such as a smartphone, a mobile phone, a tablet, a wearable terminal, or an M2M (Machine-to-Machine) communication module. As shown in FIG. 1, the terminal 20 receives control signals or data from the base station 10 via DL and transmits control signals or data to the base station 10 via UL, thereby utilizing various communication services provided by the wireless communication system. The terminal 20 may be referred to as a UE, and the base station 10 may be referred to as a gNB.

[0020] Fig. 2 shows an example of the configuration of a wireless communication system when DC (Dual Connectivity) is implemented. As shown in Fig. 2, a base station 10A serving as a Master Node (MN) and a base station 10B serving as a Secondary Node (SN) are provided. The base station 10A and the base station 10B are each connected to a core network. The terminal 20 can communicate with both the base station 10A and the base station 10B.

[0021] A cell group provided by the base station 10A, which is an MN, is called an MCG (Master Cell Group), and a cell group provided by the base station 10B, which is an SN, is called an SCG (Secondary Cell Group).

[0022] The processing operations in this embodiment may be executed in the system configuration shown in FIG. 1, in the system configuration shown in FIG. 2, or in any other system configuration.

[0023] (Example of paging monitoring operation and issues) An example of paging monitoring operation in the terminal 20 will be described below. In NR, as in LTE, paging is performed to call a terminal in standby mode when a call arrives. In NR, the terminal 20 performs discontinuous reception operation for power saving in order to monitor paging DCI. In discontinuous reception operation, the period in which the terminal 20 wakes up from a sleep state and performs paging monitoring is called a PO (paging occasion).

[0024] The terminal 20 monitors, for example, one PO per DRX cycle. A PO consists of, for example, multiple slots.

[0025] As described above, when the terminal 20 performs paging monitoring at a paging occasion (PO), it is necessary to receive a plurality of synchronization signal blocks (SSBs) in order to perform synchronization processes such as time / frequency tracking and AGC (auto gain control) in advance. The number of SSBs received in advance varies depending on the reception quality.

[0026] An example of the operation of the terminal 20 when SSB reception is performed before PO will be described with reference to Fig. 3. The upper part of Fig. 3 shows the SSB reception operation, and the lower part shows the power consumption of the terminal 20.

[0027] 3 shows an example in which the SSB period is 20 ms and three SSBs are received before PO. The terminal 20 sleeps for a long time until the timing of the SSB indicated by A, and wakes up at the timing of the SSB indicated by A. After receiving the SSB indicated by A, the terminal goes to sleep, but because it sleeps for a short time, some circuits must be kept running, which consumes power. SSB reception is similarly performed at timings B and C, and paging monitoring is performed at PO.

[0028] However, since SSB is transmitted at a relatively long interval, the terminal 20 must wake up early relative to the timing of receiving the PO in order to receive multiple SSBs. This makes it impossible to ensure a long sleep period, which leads to increased power consumption for the terminal. In the example of Figure 3, the long sleep period must end 60 ms before the PO.

[0029] For paging monitoring, in addition to or instead of SSB, TRS / CSI-RS (TRS or CSI-RS, or both), which is a reference signal transmitted at a shorter period than SSB, can be used to perform synchronization processing such as time / frequency tracking and AGC (auto gain control). Since TRS / CSI-RS can establish time and frequency synchronization with a single reception, the terminal does not need to wake up multiple times, and power consumption can be reduced.

[0030] However, the TRS / CSI-RS is a reference signal used by the terminal 20 (connected mode UE) in the RRC connection state, and is not necessarily transmitted in the cell (and beam) in which the terminal 20 is located. For example, if there is no connected mode UE connected to the beam in the cell, the base station 10 may determine that there is no need to transmit the TRS / CSI-RS and may perform control not to transmit the TRS / CSI-RS.

[0031] If it is unclear whether TRS / CSI-RS is being transmitted, the terminal 20 cannot determine in advance when it is sufficient to wake up. Therefore, as in the case of using SSB shown in Figure 3, it is necessary to wake up a longer time before PO, which increases power consumption.

[0032] In order to avoid the increase in power consumption as described above, in this embodiment, the base station 10 notifies the terminal 20 whether the TRS / CSI-RS can be used as a synchronization reference signal. Examples of signals (information) used for notification include Paging DCI, PEI (Paging Early Indication), SIB (System Information Block), etc.

[0033] Here, the basic function of the PEI will be explained. The PEI is a signal for notifying in advance whether or not the terminal 20 needs to wake up in a PO. Specifically, DCI-based PEI (DCI-based PEI) that performs notification using a DCI and RS / sequence-based PEI (RS / sequence-based PEI) that performs notification using a reference signal (or sequence) have been proposed. Note that "wake up" may be rephrased as "activation." Furthermore, "PEI" may be rephrased as "paging advance notification signal."

[0034] 4 is a diagram illustrating an example of terminal operation using a PEI. At the time point indicated by A in FIG. 4, when terminal 20 receives a PEI indicating that it is not necessary to wake up in a PO, it does not monitor the PDCCH in the PO indicated by B. At the time point indicated by C, when it receives a PEI instructing it to wake up in a PO, it monitors the PDCCH in the PO indicated by D. The PEI makes it possible to avoid unnecessary monitoring of POs.

[0035] In this embodiment, the PEI can also be used to notify whether or not the terminal 20 can use the TRS / CSI-RS as a synchronization reference signal for paging monitoring in the PO.

[0036] However, in the conventional technology, since the terminal operation in response to PEI in particular is not clear, there is a problem that the power consumption of the terminal 20 may not be reduced appropriately.

[0037] (Outline of the embodiment) In the present embodiment, the terminal operation in response to the PEI is clarified to improve the effect of reducing power consumption of the terminal 20. For example, in an example in which signals are transmitted from the base station 10 to the terminal 20 on the timeline (a diagram showing signals in chronological order) shown in Fig. 5, the terminal operation in response to the PEI is clarified.

[0038] More specifically, an example of operation of the terminal 20 when PEI is detected will be described as Example 1, and an example of operation of the terminal 20 when PEI cannot be detected will be described as Example 2. Note that, although TRS is shown below as an example of a synchronization reference signal, TRS is only an example, and a reference signal other than TRS may be used as a synchronization reference signal. The reference signal other than TRS may be CSI-RS or a reference signal other than CSI-RS. Furthermore, "detection" may be replaced with "reception".

[0039] An example of a sequence will now be described with reference to Fig. 6. In S101, the base station 10 transmits a PEI, and the terminal 20 receives the PEI. If the PEI notifies the terminal 20 that a TRS is available, the terminal 20 receives the TRS in S102 to establish synchronization, and receives paging in S103. Examples 1 and 2 will be described below. The contents described in Examples 1 and 2 can be implemented in any combination.

[0040] In the following embodiment, a case where one PO exists in one DRX cycle (discontinuous reception cycle) will be described. However, this is an example, and a setting may be made such that one DRX cycle includes multiple POs. Also, a setting may be made such that a DRX cycle does not include a PO.

[0041] Example 1 In Example 1, an example of the operation of the terminal 20 when a PEI is detected will be described. Example 1 is divided into Examples 1-1 to 1-3, and each will be described below.

[0042] In Example 1-1, the availability of a TRS is notified to the terminal 20 by a PEI transmitted from the base station 10. Regarding the time range of the TRS for which the availability is notified by the PEI, there are the following options 1 and 2.

[0043] <Option 1 of Example 1-1> In option 1, the PEI notifies the terminal 20 whether or not it is possible to use only the TRS immediately before the PO in the DRX cycle in which the PEI is received. That is, the base station 20 transmits a PEI including information indicating whether or not it is possible to use only the TRS immediately before the PO in the DRX cycle in which the PEI is transmitted.

[0044] An example of operation will be described with reference to the upper diagram of Fig. 7. In DRX cycle #0, which is the current cycle in which the terminal 20 detects the PEI, the terminal 20 receives the PEI. The PEI notifies the availability of only the TRS immediately before the PO in DRX cycle #0. Note that the TRS that the PEI notifies the availability of may be any TRS between the PEI and the PO in DRX cycle #0.

[0045] If the PEI notifies that the TRS is available and there is a wake-up instruction in the PEI, the terminal 20 receives the TRS and performs monitoring with the PO. If the PEI notifies that the TRS is unavailable, the terminal 20 does not receive the TRS (does not perform a TRS detection operation).

[0046] <Option 2 of Example 1-1> In option 2, the PEI notifies the terminal 20 whether TRX is available for use from the DRX cycle in which the PEI is received until xx DRX cycles later. That is, the base station 20 transmits a PEI including information indicating whether TRX is available for use from the DRX cycle in which the PEI is transmitted until xx DRX cycles later.

[0047] The above value of xx may be preset in the terminal 20, or may be notified from the base station 10 to the terminal 20 by, for example, SIB, DCI, MAC CE, RRC signaling, or the like.

[0048] An example of the operation of the terminal 20 when, for example, xx=2 will now be described with reference to Fig. 7. The terminal 20 receives the PEI in DRX cycle #0. The PEI notifies the terminal 20 of whether or not the TRS is available in DRX cycle #0, whether or not the TRS is available in DRX cycle #1, and whether or not the TRS is available in DRX cycle #2. The terminal 20 then performs an operation according to whether or not the TRS is available for each of these TRSs.

[0049] An example of operation when TRS is available in DRX cycle #1 and TRS is available in DRX cycle #2 will be described with reference to the middle diagram of Fig. 7. In this case, terminal 20 receives TRS in both DRX cycle #1 and DRX cycle #2.

[0050] An example of operation when TRS is unavailable in DRX cycle #1 and when TRS is unavailable in DRX cycle #2 will be described with reference to the lower diagram of Fig. 7. In this case, terminal 20 receives TRS in neither DRX cycle #1 nor DRX cycle #2. In this case, terminal 20 receives SSB and performs monitoring at PO, for example.

[0051] In the present embodiment (Examples 1 and 2), the PEI may notify whether the TRS is available and may also notify a wake-up instruction in the PO. Alternatively, there may be a PEI that notifies only whether the TRS is available and a PEI that notifies only a wake-up instruction in the PO separately.

[0052] Example 1-2 In Example 1-2, a method of notifying terminal 20 of the availability of TRS in the next DRX cycle (or the next DRX cycle or later) when a wake-up instruction in the PO of a certain DRX cycle is notified from base station 10 to terminal 20 based on the PEI in that DRX cycle will be described. The notification method includes the following options 1 to 3, and each will be described with reference to FIG. 8 as appropriate. In FIG. 8, terminal 20 in Opt (option 1) 1 and 3 receives a notification signal in the PO indicated by Opt 1 and 3, and terminal 20 in Opt 2 receives the PEI indicated by Opt 2.

[0053] The terminal 20 assumes any one or more of options 1 to 3 and performs terminal operation.

[0054] <Option 1 of Example 1-2> In option 1, it is assumed that the terminal 20 is notified of whether or not TRS will be available in the next DRX cycle (or the next DRX cycle or later) by the Paging DCI received in the PO during the current DRX cycle in which the PEI was received. In other words, in option 1, the base station 10 can notify the terminal 20 of whether or not TRS will be available in the next DRX cycle (or the next DRX cycle or later) by the Paging DCI during the current DRX cycle in which the PEI was transmitted.

[0055] For example, in FIG. 8, the terminal 20 monitors the PO during the current DRX cycle and receives a paging DCI to determine whether or not the TRS can be used in the next DRX cycle (or the next DRX cycle or later).

[0056] Furthermore, when notifying whether or not TRS is available by Paging DCI as in Option 1, it may also be possible to indicate whether or not TRS is available for the DRX cycles specified by xx as in Example 1-1. An example is shown in Fig. 9. In the example of Fig. 9, the Paging DCI received in the PO of DRX cycle #0 notifies whether or not TRS is available in DRX cycle #1 and DRX cycle #2.

[0057] The above-mentioned designation using xx is one example. The terminal 20 may use a timer to determine whether or not TRS is available for one or more DRX cycles. For example, the timer may be started at a certain point (e.g., the start of a DRX cycle), and the terminal 20 may determine the DRX cycle for which the availability of TRS is notified (how many DRX cycles the availability of TRS is notified for) based on the timer time (e.g., the time until the timer expires) at the time when the paging DCI is received.

[0058] For example, the timer time may be associated with a bit value (ID), and it may be determined that the availability of TRS for the number of DRX cycles corresponding to the bit value is being notified. Combinations of the timer time and the bit value may be organized in a table, and the terminal 20 may hold the table and determine the bit value based on the table. Furthermore, the timer time (initial value) may be notified from the base station 10 to the terminal 20.

[0059] Note that the method of using a timer as described above to determine the number of DRX cycles for notifying whether or not TRS is available may be applied to option 2 of embodiment 1-1.

[0060] <Option 2 of Example 1-2> In option 2, it is assumed that the terminal 20 is notified of whether or not TRS will be available in the next DRX cycle (or the next DRX cycle or later) by the PEI in the DRX cycle next to the current DRX cycle in which the PEI was received (or the next DRX cycle or later). In other words, in option 2, the base station 10 can notify of whether or not TRS will be available in the next DRX cycle (or the next DRX cycle or later) by the PEI in the DRX cycle next to the current DRX cycle in which the PEI was transmitted (or the next DRX cycle or later).

[0061] For example, in FIG. 8, the terminal 20 receives the PEI of the DRX Cycle next to the current DRX Cycle in which the PEI was received, and thereby determines whether or not the TRS can be used in the next DRX Cycle (or the DRX Cycle after the next DRX Cycle).

[0062] <Option 3 in Example 1-2> In option 3, it is assumed that the terminal 20 is notified of whether or not TRS will be available in the next DRX cycle (or the next DRX cycle or later) by a system information block (SIB) received in a PO during the current DRX cycle in which the PEI was received. In other words, in option 3, the base station 10 can notify the terminal 20 of whether or not TRS will be available in the next DRX cycle (or the next DRX cycle or later) by a SIB during the current DRX cycle in which the PEI was transmitted.

[0063] For example, in FIG. 8, the terminal 20 monitors the PO during the current DRX cycle and receives the SIB to determine whether or not the TRS can be used in the next DRX cycle (or the next DRX cycle or later).

[0064] Furthermore, even when notifying by SIB, it is also possible to indicate whether or not the DRX cycle specified by xx can be used, as shown in Fig. 9. Furthermore, the method using a timer described in Option 1 of Example 1-2 may also be applied when notifying by SIB.

[0065] The SIB to be used is not limited to a specific SIB. The SIB to be used may be SIB1, SIB2, or an SIB not specified in the existing regulations. Furthermore, an MIB may be used instead of an SIB.

[0066] <Example 1-2: Regarding operation switching> Regarding switching from an operation of determining whether or not TRS is available based on PEI to an operation of determining whether or not TRS is available based on Paging DCI, SIB, etc. received in PO, as in Options 1 and 3 above, the terminal 20 may decide to use notification in PO when it detects that either or both of the following operation selection criteria (1) and (2) are satisfied.

[0067] (1) The number of consecutive wake-up instructions issued by the PEI exceeds a threshold value.

[0068] (2) The Group Paging Rate in the PO exceeds (or falls below) a threshold value.

[0069] Regarding (1), if the condition (1) is satisfied, wake-up via PO is frequently performed, so it is effective to use a signal received via PO rather than PEI. Regarding (2), if the condition (2) is satisfied, there is a high possibility of receiving paging via PO, so it is effective to use paging DCI received via PO rather than PEI.

[0070] Any one of the above options 1 to 3 may be implemented, or any two or more (or all) of them may be implemented. Furthermore, any one or more terminal operations of options 1 to 3 and the above thresholds may be set in advance in the terminal 20, or may be set or changed from the base station 10 to the terminal 20. As a notification method from the base station 10, for example, SIB, DCI, MAC CE, RRC Signaling, etc. may be used.

[0071] <Example 1-3> Example 1-3 is a detailed example of the case of Option 1 in Example 1-2. As described above, in Option 1 in Example 1-2, the terminal 20 determines whether or not TRS is available in the next DRX cycle (or the next DRX cycle or later) based on the Paging DCI during the current DRX cycle in which the PEI is received. The terminal 20 performs the following Alt1 operation or Alt2 operation depending on the result of the determination of whether or not TRS is available based on the Paging DCI. Note that Example 1-3 may be applied to the case of Option 3 in Example 1-2 (the case in which an SIB is used).

[0072] Furthermore, when the availability of TRS for multiple DRX cycles is notified in the Paging DCI, the following Alt1 and Alt2 may be implemented in each DRX cycle for which the availability of TRS is notified.

[0073] <Alt1 of Example 1-3> Alt1 is an operation performed when the terminal 20 determines that the TRS is not available based on the Paging DCI. In this case, the terminal 20 monitors the PEI in the DRX Cycle following the current DRX Cycle in which the Paging DCI was received (for example, monitors the PEI shown in FIG. 10 ).

[0074] If the availability of TRS in the Paging DCI differs from the availability of TRS in the next or subsequent DRX cycle according to the PEI, this can be detected by monitoring the PEI as described above.

[0075] <Alt2 in Example 1-3> Alt2 is an operation performed when the terminal 20 determines that the TRS is available. In this case, the terminal 20 performs one of the following operations, Alt2-1 and Alt2-2.

[0076] <Alt2-1> In Alt2-1, the terminal 20 monitors the PEI in the DRX Cycle following the current DRX Cycle in which the paging DCI was received. This PEI is shown as the PEI in the timeline of Alt2-1 in FIG.

[0077] In this case, the resource location of the PEI may be set in advance in the terminal 20, or may be notified or changed from the base station 10 to the terminal 20.

[0078] For example, when it is determined that a TRS is available based on the Paging DCI, the time position of the PEI resource may be preset to immediately after SSB #3. Here, SSB #3 is the SSB immediately before (closest in time to) the PO in the DRX cycle. The reason for this is that since it is known that a TRS can be received, sufficient synchronization can be established by receiving one SSB plus the TRS. This allows the second and third SSBs to be skipped, reducing unnecessary activations and power consumption.

[0079] Furthermore, the base station 10 may notify the terminal 20 by using the Paging DCI in option 1 in embodiment 1-2 whether a PEI resource is set immediately after SSB#3.

[0080] By receiving the PEI as in Alt2-1, the terminal 20 can determine whether or not to wake up at the PO based on the PEI.

[0081] <Alt2-2> In Alt2-2, the terminal 20 does not monitor the PEI in the DRX Cycle following the current DRX Cycle in which the Paging DCI was received. This situation is indicated by the absence of a PEI in the timeline of Alt2-2 in Fig. 11. In this case, for example, the terminal 20 receives a TRS and wakes up at a PO.

[0082] <Regarding Operation Selection> Which operation of Alt2-1 or 2-2 the terminal 20 will perform may be preset in the terminal 20, or may be notified to or changed by the base station 10 to the terminal 20. Furthermore, which operation the terminal 20 will perform may depend on the implementation of each individual terminal 20.

[0083] As a notification method when the base station 10 notifies (or changes) the operation to the terminal 20, for example, SIB, DCI, MAC CE, or RRC Signaling can be used.

[0084] The terminal 20 may also select which of Alt2-1 and 2-2 to execute by comparing a parameter that serves as a criterion for judgment with a threshold value.

[0085] As the reference parameter, any one or more of {Group Paging Rate in PO, mobility of terminal 20, location information of terminal 20, UE category of terminal 20, UE type of terminal 20} may be used.

[0086] For example, if the Group Paging Rate exceeds a threshold and there is a high possibility of receiving paging, paging monitoring may be performed at the PO without monitoring the PEI.

[0087] The parameter threshold may be set in advance in the terminal 20, or may be notified or changed from the base station 10 to the terminal 20. As a notification method when the base station 10 notifies (or changes) the threshold to the terminal 20, for example, SIB, DCI, MAC CE, or RRC Signaling can be used.

[0088] <Example 1-3: Regarding application designation by PEI> In the above-mentioned Att1 and Alt2, when the terminal 20 receives a PEI at a DRX cycle designated by a Paging DCI, the terminal 20 may perform an operation for a different application based on bits (multiple bits) used to determine whether or not TRS is available in the PEI.

[0089] For example, when the base station 10 notifies the terminal 20 of 12 bits by PEI, it is assumed that one bit of the PEI notifies whether the first DRX cycle is available and another bit notifies whether the second DRX cycle is available.

[0090] In this case, in a DRX cycle after the availability of TRS has been notified to the terminal 20, the above two bits are used for notification of another purpose during that cycle. For example, the terminal 20 may determine that one bit is for notification of ETWS and the other bit is for notification of Sib Update or the like.

[0091] An example is shown in Figure 12. In the example of Figure 12, the Paging DCI received in DRX cycle #0 notifies the availability of TRS in each of DRX cycle #1 and DRX cycle #2. At this time, terminal 20 receives PEI in DRX cycle #1 and #2, interprets the bit in the PEI for notifying the availability of TRS as a bit for notifying a different purpose, and performs a decision or operation according to the value of that bit. For example, if the bit interpreted as the bit for ETWS is ON, the operation to be performed when an emergency alert is received is performed.

[0092] According to the first embodiment described above, the terminal operation when the PEI is detected becomes clear, and the power consumption reduction effect of the terminal 20 can be improved.

[0093] (Example 2) In Example 2, an example of the operation of the terminal 20 when the PEI cannot be detected will be described. Example 2 is divided into Examples 2-1 to 2-3, and each will be described separately. When the PEI cannot be detected, it means that the PEI cannot be detected when an operation to monitor the PEI is performed. The case where the operation to monitor the PEI is performed includes not only the case where the operation to monitor the PEI is performed in Example 1, but also other cases.

[0094] Fig. 13 is a diagram for explaining an example of a case where the PEI cannot be detected. In the example shown in the upper part of Fig. 13, the PEI is transmitted from the base station 10. In this case, for example, if the wireless state deteriorates, the terminal 20 may not be able to detect the PEI.

[0095] In the example shown in the lower part of Fig. 13, the terminal 20 monitors the PEI for each DRX cycle, for example, in accordance with the DRX cycle setting information, but the PEI is not necessarily transmitted for each DRX cycle. For example, if there are no resources for transmitting the PEI, the base station 10 does not transmit the PEI. In this case, the terminal 20 cannot detect the PEI at the expected timing.

[0096] <Example 2-1> If the terminal 20 cannot detect the PEI, it performs one of the operations described in Options 1 to 3 below.

[0097] Which of options 1 to 3 to perform may be preset in the terminal 20, may be notified or changed by the base station 10 to the terminal 20, or may depend on the implementation of each individual terminal 20.

[0098] As a notification method when the base station 10 notifies (or changes) the terminal 20, for example, SIB, DCI, MAC CE, and RC Signaling can be used.

[0099] <Example 2-1: Option 1> If the terminal 20 cannot detect the PEI of a certain DRX cycle, it assumes that the TRS of that DRX cycle is available, skips receiving the subsequent SSB, completes synchronization establishment using the TRS, and wakes up at the PO of that DRX cycle. This example is assumed to be an example in which the base station 10 transmits the TRS when the base station 10 does not transmit the PEI.

[0100] <Example 2-1: Option 2> If the terminal 20 cannot detect the PEI of a certain DRX cycle, it assumes that the TRS of that DRX cycle is unavailable and establishes synchronization by receiving the subsequent SSB. In other words, it completes synchronization establishment using only the SSB and wakes up with the PO of that DRX cycle.

[0101] <Example 2-1: Option 3> If the terminal 20 cannot detect the PEI of a certain DRX cycle, the terminal 20 does not wake up at the PO of that DRX cycle. In other words, the terminal 20 does not receive the subsequent SSB and TRS and skips them.

[0102] Example 2-2 In Example 2-2, a method for notifying the terminal 20 of the availability of TRS in the next DRX cycle (or the next DRX cycle or later) when the terminal 20 is unable to detect the PEI in a certain DRX cycle will be described. The notification method includes the following options 1 to 3, and each will be described with reference to FIG. 14 as appropriate. In FIG. 14, the terminal 20 in Opt (option 1) 1 and 3 receives a notification signal at the PO indicated by Opt 1 and 3, and the terminal 20 in Opt 2 receives the PEI indicated by Opt 2.

[0103] The terminal 20 assumes any one or more of options 1 to 3 and performs terminal operation.

[0104] <Option 1 of Example 2-2> In option 1, it is assumed that the terminal 20 is notified of whether or not TRS will be available in the next DRX cycle (or the next DRX cycle or later) by the Paging DCI during the current DRX cycle in which the PEI was not detected. In other words, in option 1, the base station 10 can notify the terminal 20 of whether or not TRS will be available in the next DRX cycle (or the next DRX cycle or later) by the Paging DCI during the current DRX cycle.

[0105] For example, in FIG. 14, the terminal 20 monitors the PO during the current DRX cycle and receives a Paging DCI to determine whether or not the TRS can be used in the next DRX cycle (or the next DRX cycle or later).

[0106] Also, similarly to option 1 in embodiment 1-2, as shown in FIG. 9, it is possible to instruct whether or not a specified DRX cycle is available.

[0107] <Option 2 of Example 2-2> In option 2, it is assumed that the terminal 20 is notified of whether or not TRS will be available in the next DRX cycle (or the next DRX cycle or later) based on the PEI in the DRX cycle next to the current DRX cycle in which the PEI could not be detected. In other words, in option 2, the base station 10 can notify whether or not TRS will be available in the next DRX cycle (or the next DRX cycle or later) based on the PEI in the DRX cycle next to the current DRX cycle (or the next DRX cycle or later).

[0108] For example, in FIG. 14, the terminal 20 receives the PEI of the DRX cycle next to the current DRX cycle in which the PEI has not been detected, and thereby determines whether or not the TRS of the next DRX cycle is available.

[0109] <Option 3 of Example 2-2> In option 3, it is assumed that the terminal 20 is notified of whether or not TRS will be available in the next DRX cycle (or the next DRX cycle or later) by an SIB received in a PO during the current DRX cycle in which the PEI was not detected. In other words, in option 3, the base station 10 can notify the terminal 20 of whether or not TRS will be available in the next DRX cycle (or the next DRX cycle or later) by an SIB during the current DRX cycle.

[0110] For example, in FIG. 14, the terminal 20 monitors the PO during the current DRX cycle and receives the SIB to determine whether or not the TRS can be used in the next DRX cycle (or the next DRX cycle or later).

[0111] Also, even when notifying by SIB, as shown in FIG. 9, it is possible to indicate whether or not the DRX cycle specified by xx can be used.

[0112] The SIB to be used is not limited to a specific SIB. The SIB to be used may be SIB1, SIB2, or an SIB not specified in the existing regulations. Furthermore, an MIB may be used instead of an SIB.

[0113] <Example 2-3> When the notification of TRS availability is performed by PEI, the method of notifying TRS availability may be switched from PEI to Paging DCI or SIB. This "switching" may be switching from a state in which the above-mentioned option 2 is implemented to a state in which the above-mentioned options 1 and 3 are implemented.

[0114] For example, the terminal 20 may decide to switch and transmit a switching instruction to the base station 10 , or the base station 10 may transmit a switching instruction to the terminal 20 .

[0115] An example of a switching criterion will be described. For example, when the terminal 20 cannot detect the PEI consecutively for a threshold number of times or more, the TRS availability notification method is switched from the PEI to the Paging DCI or the SIB. For example, when switching from the PEI to the Paging DCI, the terminal 20 determines whether the TRS is available by monitoring the Paging DCI without monitoring the PEI.

[0116] The above criteria, thresholds, etc. may be set in advance in the terminal 20, or may be notified to the terminal 20 by the base station 10 or may be changed.

[0117] As a notification method when the base station 10 notifies the terminal 20, for example, SIB, DCI, MAC CE, or RRC Signaling can be used.

[0118] According to the second embodiment described above, the terminal operation when the PEI cannot be detected becomes clear, and the power consumption reduction effect of the terminal 20 can be improved.

[0119] (Other Examples) In the first and second embodiments described above, the number of SSBs used for reception may be three or more. In the descriptions of the first and second embodiments, a timeline using a maximum of three SSBs is used as an example.

[0120] Furthermore, in the first and second embodiments described so far, when the base station 10 notifies the terminal 20 of availability information for a certain TRS by both the PEI and the Paging DCI, and the availability information differs, the terminal 20 may implement any one of the following (1) to (3).

[0121] (1) PEI (or paging DCI) information takes precedence.

[0122] (2) The most recent information on whether TRS is available or not is given priority.

[0123] (3) If the notification of availability differs, it is always recognized as available (or always recognized as unavailable).

[0124] Which of the operations (1) to (3) to perform may be preset in the terminal 20, or may be notified or changed by the base station 10 to the terminal 20. Also, which operation the terminal 20 performs may depend on the implementation of each individual terminal 20.

[0125] For example, SIB, DCI, MAC CE, and RRC Signaling can be used as a notification method when the base station 10 notifies (or changes) an operation to the terminal 20. Furthermore, the "Paging DCI" above (and below) may be replaced with "SIB."

[0126] Here, the above operation (2) will be explained in more detail using examples 1 to 3.

[0127] Example 1: Assume that the PO for DRX cycle #0 notifies that "TRS can be used from DRX cycle #1 to #3." If the PEI for DRX cycle #1 notifies that "TRS cannot be used from #2 to #3," the PEI for DRX cycle #1 has priority because it is the most up-to-date information.

[0128] Example 2: Assume that the PEI for DRX cycle #0 notifies that "TRS can be used from DRX cycle #1 to #3." If the immediately following PO (PO #0) notifies that "TRS cannot be used from #1 to #3," the PO has priority because it is the most up-to-date information.

[0129] Example 3: If the PEI for DRX cycle #0 notifies that "TRS can be used from #1 to #3" and the PO (paging DCI) for DRX cycle #1 notifies that "TRS cannot be used from #2 to #3," the information in the paging DCI received later takes priority and it is determined that TRS cannot be used.

[0130] (Device Configuration) Next, a functional configuration example of the base station 10 and the terminal 20 that execute the processes and operations described above will be described. The base station 10 and the terminal 20 include functions for implementing the above-described Examples 1 and 2. However, the base station 10 and the terminal 20 may each be equipped with only the functions of any one of Examples 1 and 2.

[0131] <Base Station 10> Fig. 15 is a diagram showing an example of the functional configuration of the base station 10. As shown in Fig. 15, the base station 10 has a transmitting unit 110, a receiving unit 120, a setting unit 130, and a control unit 140. The functional configuration shown in Fig. 15 is merely an example. The names of the functional divisions and functional units may be any as long as they can perform the operations related to the embodiment of the present invention. The transmitting unit 110 and the receiving unit 120 may be called a communication unit.

[0132] The transmitter 110 has a function of generating a signal to be transmitted to the terminal 20 and transmitting the signal wirelessly. The receiver 120 has a function of receiving various signals transmitted from the terminal 20 and acquiring, for example, information of a higher layer from the received signal. The transmitter 110 also has a function of transmitting NR-PSS, NR-SSS, NR-PBCH, DL / UL control signals, DL data, etc. to the terminal 20. The transmitter 110 also transmits the notifications (instructions) described in Examples 1 to 5 to the terminal 20.

[0133] The setting unit 130 stores preset setting information and various setting information to be transmitted to the terminal 20 in a storage device, and reads out the information from the storage device as needed.

[0134] The control unit 140 performs, for example, resource allocation and overall control of the base station 10. Note that the functional unit in the control unit 140 related to signal transmission may be included in the transmitting unit 110, and the functional unit in the control unit 140 related to signal reception may be included in the receiving unit 120. Furthermore, the transmitting unit 110 and the receiving unit 120 may be called a transmitter and a receiver, respectively.

[0135] <Terminal 20> Fig. 16 is a diagram showing an example of the functional configuration of the terminal 20. As shown in Fig. 16, the terminal 20 has a transmitting unit 210, a receiving unit 220, a setting unit 230, and a control unit 240. The functional configuration shown in Fig. 16 is merely an example. The names of the functional divisions and functional units may be any as long as they can execute the operations related to the embodiment of the present invention. The transmitting unit 210 and the receiving unit 220 may be called a communication unit.

[0136] The transmitter 210 generates a transmission signal from transmission data and transmits the transmission signal wirelessly. The receiver 220 receives various signals wirelessly and acquires higher layer signals from the received physical layer signals.

[0137] The setting unit 230 stores various setting information received from the base station 10 by the receiving unit 220 in a storage device and reads it from the storage device as needed. The setting unit 230 also stores setting information that is set in advance. The content of the setting information is, for example, information necessary for the operations described in Examples 1 and 2.

[0138] The control unit 240 performs control related to paging monitoring based on information received from the base station 10. Note that the functional unit related to signal transmission in the control unit 240 may be included in the transmitting unit 210, and the functional unit related to signal reception in the control unit 240 may be included in the receiving unit 220. Furthermore, the transmitting unit 210 and the receiving unit 220 may be called a transmitter and a receiver, respectively.

[0139] This embodiment provides at least a terminal as described in the following paragraphs: (Clause 1) A terminal comprising: a receiving unit that detects a paging advance notification signal; and a control unit that determines, based on the paging advance notification signal, whether a synchronization reference signal is available in each of one or more discontinuous reception cycles. (Clause 2) A terminal comprising: a receiving unit that detects a paging advance notification signal that instructs activation at a paging opportunity in a first discontinuous reception cycle; and a control unit that determines, based on the signal received at the paging opportunity, whether a synchronization reference signal is available in a second discontinuous reception cycle that is subsequent to the first discontinuous reception cycle. (Clause 3) The terminal described in paragraph 2, wherein the receiving unit monitors the paging advance notification signal in the second discontinuous reception cycle when the control unit determines, based on the signal received at the paging opportunity, that a synchronization reference signal is unavailable in the second discontinuous reception cycle. (Clause 4) The terminal according to Clause 2, wherein, when the control unit determines, based on the signal received at the paging opportunity, that a synchronization reference signal in the second discontinuous reception cycle is available, the receiving unit monitors a paging advance notification signal that is located at a time position after the synchronization signal in the second discontinuous reception cycle. (Clause 5) A terminal comprising: a receiving unit that monitors paging advance notification signals, and a control unit that, when the receiving unit is unable to detect the paging advance notification signal, determines, based on settings, that a synchronization reference signal is available or that a synchronization reference signal is unavailable. (Clause 6) A terminal comprising: a receiving unit that monitors paging advance notification signals in a first discontinuous reception cycle, and a control unit that, when the receiving unit is unable to detect the paging advance notification signal, determines, based on signals received at paging opportunities in the first discontinuous reception cycle, that a synchronization reference signal is available in a second discontinuous reception cycle that is after the first discontinuous reception cycle.

[0140] Any of the first to sixth paragraphs makes it possible to appropriately reduce the power consumption of the terminal during paging monitoring. The third and fourth paragraphs make it possible to respond to changes in the availability of synchronization reference signals.

[0141] (Hardware Configuration) The block diagrams (FIGS. 15 and 16) used to explain the above embodiments show functional blocks. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method for realizing each functional block is not particularly limited. That is, each functional block may be realized using a single device that is physically or logically coupled, or may be realized using two or more physically or logically separated devices that are directly or indirectly connected (for example, using wires, wirelessly, etc.) and these multiple devices. The functional block may be realized by combining software with the single device or the multiple devices.

[0142] Functions include, but are not limited to, judgment, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, election, establishment, comparison, assumption, expectation, consideration, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs transmission is called a transmitting unit or transmitter. As described above, the implementation method of each is not particularly limited.

[0143] For example, the base station 10, the terminal 20, etc. according to an embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method of the present disclosure. Fig. 17 is a diagram illustrating an example of the hardware configuration of the base station 10 and the terminal 20 according to an embodiment of the present disclosure. The base station 10 and the terminal 20 described above may be physically configured as a computer device including a processor 1001, a storage device 1002, an auxiliary storage device 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

[0144] In the following description, the term "apparatus" can be interpreted as a circuit, a device, a unit, etc. The hardware configuration of the base station 10 and the terminal 20 may be configured to include one or more of the apparatuses shown in the drawings, or may be configured to exclude some of the apparatuses.

[0145] Each function in the base station 10 and the terminal 20 is realized by loading specified software (programs) onto hardware such as the processor 1001, the memory device 1002, etc., so that the processor 1001 performs calculations, controls communication by the communication device 1004, and controls at least one of reading and writing data in the memory device 1002 and the auxiliary memory device 1003.

[0146] The processor 1001 controls the entire computer by running, for example, an operating system. The processor 1001 may be configured as a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic unit, a register, etc. For example, the above-mentioned control unit 140, control unit 240, etc. may be realized by the processor 1001.

[0147] Furthermore, the processor 1001 reads programs (program codes), software modules, data, etc. from at least one of the auxiliary storage device 1003 and the communication device 1004 into the storage device 1002 and executes various processes in accordance with the programs. The programs used are those that cause a computer to execute at least some of the operations described in the above-described embodiments. For example, the control unit 140 of the base station 10 shown in FIG. 15 may be implemented by a control program stored in the storage device 1002 and running on the processor 1001. Furthermore, for example, the control unit 240 of the terminal 20 shown in FIG. 16 may be implemented by a control program stored in the storage device 1002 and running on the processor 1001. While the above-described various processes have been described as being executed by one processor 1001, they may also be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 may be implemented by one or more chips. The programs may also be transmitted from a network via a telecommunications line.

[0148] The storage device 1002 is a computer-readable recording medium and may be configured, for example, by at least one of a ROM (Read Only Memory), an EPROM (Erasable Programmable ROM), an EEPROM (Electrically Erasable Programmable ROM), a RAM (Random Access Memory), etc. The storage device 1002 may also be called a register, a cache, a main memory, etc. The storage device 1002 can store executable programs (program codes), software modules, etc. for implementing a communication method according to an embodiment of the present disclosure.

[0149] The secondary storage device 1003 is a computer-readable recording medium, and may be composed of, for example, at least one of an optical disk such as a CD-ROM (Compact Disc ROM), a hard disk drive, a flexible disk, a magneto-optical disk (e.g., a compact disk, a digital versatile disk, a Blu-ray (registered trademark) disk), a smart card, a flash memory (e.g., a card, a stick, a key drive), a floppy (registered trademark) disk, a magnetic strip, etc. The secondary storage device 1003 may also be referred to as an auxiliary storage device. The above-mentioned storage medium may be, for example, a database, a server, or other appropriate medium including at least one of the storage device 1002 and the secondary storage device 1003.

[0150] The communication device 1004 is hardware (transmission / reception device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as, for example, a network device, a network controller, a network card, or a communication module. The communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. to realize at least one of frequency division duplex (FDD) and time division duplex (TDD). For example, a transmission / reception antenna, an amplifier unit, a transmission / reception unit, a transmission path interface, etc. may be realized by the communication device 1004. The transmission / reception unit may be implemented as a transmission unit and a reception unit that are physically or logically separated.

[0151] The input device 1005 is an input device (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that receives input from the outside. The output device 1006 is an output device (e.g., a display, a speaker, an LED lamp, etc.) that outputs to the outside. Note that the input device 1005 and the output device 1006 may be integrated into one device (e.g., a touch panel).

[0152] Furthermore, each device such as the processor 1001 and the storage device 1002 is connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using different buses between each device.

[0153] Furthermore, the base station 10 and the terminal 20 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA), and some or all of the functional blocks may be realized by the hardware. For example, the processor 1001 may be implemented using at least one of these pieces of hardware.

[0154] Furthermore, the terminal 20 or the base station 10 may be provided in the vehicle 1. An example of the configuration of the vehicle 1 is shown in FIG.

[0155] As shown in Figure 18, the vehicle 1 comprises a drive unit 2, a steering unit 3, an accelerator pedal 4, a brake pedal 5, a shift lever 6, left and right front wheels 7, left and right rear wheels 8, an axle 9, an electronic control unit 11, various sensors 21 to 29, an information service unit 12 and a communication module 13.

[0156] The drive unit 2 is configured, for example, by an engine, a motor, or a hybrid of an engine and a motor. The steering unit 3 includes at least a steering wheel (also called a handle) and is configured to steer at least one of the front wheels and the rear wheels based on the operation of the steering wheel operated by a user.

[0157] The electronic control unit 11 is composed of a microprocessor 31, memory (ROM, RAM) 32, and a communication port (IO port) 33. Signals are input to the electronic control unit 11 from various sensors 21 to 27 provided in the vehicle. The electronic control unit 11 may also be called an ECU (Electronic Control Unit).

[0158] The signals from the various sensors 21 to 28 include a current signal from a current sensor 21 that senses the current of the motor, a rotation speed signal of the front and rear wheels obtained by a rotation speed sensor 22, an air pressure signal of the front and rear wheels obtained by an air pressure sensor 23, a vehicle speed signal obtained by a vehicle speed sensor 24, an acceleration signal obtained by an acceleration sensor 25, an accelerator pedal depression amount signal obtained by an accelerator pedal sensor 29, a brake pedal depression amount signal obtained by a brake pedal sensor 26, a shift lever operation signal obtained by a shift lever sensor 27, and a detection signal for detecting obstacles, vehicles, pedestrians, etc. obtained by an object detection sensor 28.

[0159] The information service unit 12 is composed of various devices, such as a car navigation system, an audio system, speakers, a television, and a radio, for providing various types of information such as driving information, traffic information, and entertainment information, and one or more ECUs for controlling these devices. The information service unit 12 provides various types of multimedia information and multimedia services to the occupants of the vehicle 1 by using information acquired from external devices via the communication module 13, etc.

[0160] The driving assistance system unit 30 is composed of various devices that provide functions for preventing accidents and reducing the driver's driving burden, such as millimeter-wave radar, LiDAR (Light Detection and Ranging), cameras, positioning locators (e.g., GNSS, etc.), map information (e.g., high-definition (HD) maps, autonomous vehicle (AV) maps, etc.), gyro systems (e.g., IMU (Inertial Measurement Unit), INS (Inertial Navigation System), etc.), AI (Artificial Intelligence) chips, and AI processors, as well as one or more ECUs that control these devices. In addition, the driving assistance system unit 30 transmits and receives various information via the communication module 13 to realize the driving assistance function or the autonomous driving function.

[0161] The communication module 13 can communicate with the microprocessor 31 and components of the vehicle 1 via the communication port. For example, the communication module 13 transmits and receives data via the communication port 33 to and from the drive unit 2, steering unit 3, accelerator pedal 4, brake pedal 5, shift lever 6, left and right front wheels 7, left and right rear wheels 8, axles 9, microprocessor 31 and memory (ROM, RAM) 32 in the electronic control unit 11, and sensors 21 to 28, which are provided in the vehicle 1.

[0162] The communication module 13 is a communication device that can be controlled by the microprocessor 31 of the electronic control unit 11 and can communicate with an external device. For example, it transmits and receives various information to and from the external device via wireless communication. The communication module 13 may be located either inside or outside the electronic control unit 11. The external device may be, for example, a base station, a mobile station, or the like.

[0163] The communication module 13 transmits, via wireless communication, to an external device a current signal from the current sensor that is input to the electronic control unit 11. The communication module 13 also transmits, via wireless communication, to an external device, the rotation speed signals of the front and rear wheels acquired by the rotation speed sensor 22, the air pressure signals of the front and rear wheels acquired by the air pressure sensor 23, the vehicle speed signal acquired by the vehicle speed sensor 24, the acceleration signal acquired by the acceleration sensor 25, the accelerator pedal depression amount signal acquired by the accelerator pedal sensor 29, the brake pedal depression amount signal acquired by the brake pedal sensor 26, the shift lever operation signal acquired by the shift lever sensor 27, and the detection signals for detecting obstacles, vehicles, pedestrians, etc. acquired by the object detection sensor 28, all of which are input to the electronic control unit 11.

[0164] The communication module 13 receives various information (traffic information, traffic signal information, vehicle distance information, etc.) transmitted from external devices and displays it on the information service unit 12 provided in the vehicle. The communication module 13 also stores the various information received from external devices in a memory 32 that can be used by the microprocessor 31. Based on the information stored in the memory 32, the microprocessor 31 may control the drive unit 2, steering unit 3, accelerator pedal 4, brake pedal 5, shift lever 6, left and right front wheels 7, left and right rear wheels 8, axles 9, sensors 21 to 28, and the like provided in the vehicle 1.

[0165] The communication module 13 may be the terminal 20 or the base station 10 described in the present embodiment.

[0166] (Supplementary Notes on the Embodiments) Although the embodiments of the present invention have been described above, the disclosed invention is not limited to such embodiments, and those skilled in the art will understand various modifications, alterations, alternatives, and substitutions. While specific numerical examples have been used to facilitate understanding of the invention, unless otherwise specified, these numerical values ​​are merely examples, and any appropriate values ​​may be used. The division of items in the above description is not essential to the present invention; matters described in two or more items may be used in combination as needed, and matters described in one item may apply to matters described in another item (as long as there is no contradiction). Boundaries between functional units or processing units in functional block diagrams do not necessarily correspond to boundaries between physical components. The operations of multiple functional units may be performed by a single physical component, or the operations of a single functional unit may be performed by multiple physical components. The order of processing steps described in the embodiments may be reversed as long as there is no contradiction. For convenience of processing description, the base station 10 and terminal 20 have been described using functional block diagrams, but such devices may be realized by hardware, software, or a combination thereof. The software operated by the processor of the base station 10 in accordance with an embodiment of the present invention and the software operated by the processor of the terminal 20 in accordance with an embodiment of the present invention may each be stored in random access memory (RAM), flash memory, read-only memory (ROM), EPROM, EEPROM, register, hard disk (HDD), removable disk, CD-ROM, database, server, or any other suitable storage medium.

[0167] Furthermore, notification of information is not limited to the aspects / embodiments described in this disclosure, and may be performed using other methods. For example, the notification of information may be performed by physical layer signaling (e.g., Downlink Control Information (DCI) and Uplink Control Information (UCI)), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information (Master Information Block (MIB) and System Information Block (SIB)), other signals, or a combination thereof. Furthermore, the RRC signaling may be referred to as an RRC message, and may be, for example, an RRC connection setup message. The message may be an RRC Setup message, an RRC Connection Reconfiguration message, or the like.

[0168] Each aspect / embodiment described in the present disclosure may be implemented using any of the following standards: LTE (Long Term Evolution), LTE-Advanced (LTE-A), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication system), 5G (5th generation mobile communication system), 6th generation mobile communication system (6G), xth generation mobile communication system (xG) (xG (x is, for example, an integer or a decimal number)), FRA (Future Radio Access), NR (new Radio), New radio access (NX), Future generation radio access (FX), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.17 (WiMAX (registered trademark)), IEEE 802.19 (WiMAX (registered trademark)), IEEE 802.20 (WiMAX (registered trademark)), IEEE 802.21 (Wi-Fi (registered trademark)), IEEE 802.22 (WiMAX (registered trademark)), IEEE 802.23 (WiMAX (registered trademark)), IEEE 802.24 (WiMAX (registered trademark)), IEEE 802.25 (WiMAX (registered trademark)), IEEE 802.26 (WiMAX (registered trademark)), IEEE 802.27 (WiMAX (registered trademark)), IEEE 802.28 (WiMAX (registered trademark)), IEEE 802.29 (WiMAX (registered trademark)), IEEE 802.30 (WiMAX (registered trademark)), IEEE 802.31 (Wi-Fi (registered trademark)), IEEE 802.32 (WiMAX (registered trademark)), IEEE 802.33 (WiMAX (registered trademark)), IEEE 802.34 ( The present invention may be applied to at least one of systems using 802.20, UWB (Ultra-Wide Band), Bluetooth (registered trademark), or other suitable systems, and next-generation systems that are extended, modified, created, or defined based on these systems. The present invention may also be applied to a combination of multiple systems (e.g., a combination of LTE and / or LTE-A with 5G).

[0169] The order of the procedures, sequences, flowcharts, etc. of each aspect / embodiment described herein may be rearranged unless it is consistent. For example, the methods described in this disclosure present elements of various steps using an example order and are not limited to the particular order presented.

[0170] In this specification, a specific operation described as being performed by the base station 10 may be performed by its upper node in some cases. In a network consisting of one or more network nodes having the base station 10, it is clear that various operations performed for communication with the terminal 20 may be performed by at least one of the base station 10 and another network node other than the base station 10 (such as, but not limited to, an MME or an S-GW). Although the above example illustrates a case where there is one other network node other than the base station 10, the other network node may be a combination of multiple other network nodes (such as an MME and an S-GW).

[0171] The information, signals, etc. described in the present disclosure may be output from a higher layer (or a lower layer) to a lower layer (or a higher layer), or may be input / output via multiple network nodes.

[0172] Input and output information may be stored in a specific location (for example, memory) or may be managed using a management table. Input and output information may be overwritten, updated, or added to. Output information may be deleted. Input information may be sent to another device.

[0173] In the present disclosure, the determination may be made by a value represented by one bit (0 or 1), by a Boolean value (true or false), or by a comparison of numerical values ​​(e.g., comparison with a predetermined value).

[0174] Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

[0175] Software, instructions, information, etc. may also be transmitted or received over a transmission medium. For example, if software is transmitted from a website, server, or other remote source using wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and / or wireless technologies (such as infrared, microwave), then these wired and / or wireless technologies are included within the definition of transmission media.

[0176] The information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0177] Note that terms described in this disclosure and terms necessary for understanding this disclosure may be replaced with terms having the same or similar meanings. For example, at least one of a channel and a symbol may be a signal (signaling). Furthermore, a signal may be a message. Furthermore, a component carrier (CC) may be called a carrier frequency, a cell, a frequency carrier, etc.

[0178] As used in this disclosure, the terms "system" and "network" are used interchangeably.

[0179] Furthermore, the information, parameters, etc. described in the present disclosure may be expressed using absolute values, may be expressed using relative values ​​from a predetermined value, or may be expressed using other corresponding information. For example, a radio resource may be indicated by an index.

[0180] The names used for the above-described parameters are not intended to be limiting in any way. Furthermore, the mathematical expressions using these parameters may differ from those explicitly disclosed in this disclosure. The various channels (e.g., PUSCH, PUCCH, PDCCH, etc.) and information elements may be identified by any suitable names, and therefore the various names assigned to these various channels and information elements are not intended to be limiting in any way.

[0181] In the present disclosure, terms such as "base station (BS)," "radio base station," "base station," "fixed station," "NodeB," "eNodeB (eNB)," "gNodeB (gNB)," "access point," "transmission point," "reception point," "transmission / reception point," "cell," "sector," "cell group," "carrier," and "component carrier" may be used interchangeably. A base station may also be referred to by terms such as a macrocell, a small cell, a femtocell, and a picocell.

[0182] A base station can accommodate one or more (e.g., three) cells. When a base station accommodates multiple cells, the overall coverage area of ​​the base station can be partitioned into multiple smaller areas, and each smaller area can also be provided with communication services by a base station subsystem (e.g., a remote radio head (RRH)). The terms "cell" or "sector" refer to part or the entire coverage area of ​​a base station and / or base station subsystem that provides communication services within that coverage area.

[0183] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," etc. may be used interchangeably.

[0184] A mobile station may also be referred to by those skilled in the art as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable terminology.

[0185] At least one of the base station and the mobile station may be referred to as a transmitting device, a receiving device, a communication device, etc. At least one of the base station and the mobile station may be a device mounted on a mobile body, the mobile body itself, etc. The mobile body may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile body (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). At least one of the base station and the mobile station may also include devices that do not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an IoT (Internet of Things) device such as a sensor.

[0186] Furthermore, the base station in the present disclosure may be read as a terminal. For example, each aspect / embodiment of the present disclosure may be applied to a configuration in which communication between a base station and a terminal is replaced with communication between a plurality of terminals 20 (which may be called, for example, D2D (Device-to-Device) or V2X (Vehicle-to-Everything)). In this case, the terminal 20 may be configured to have the functions of the base station 10 described above. Furthermore, terms such as "uplink" and "downlink" may be read as terms corresponding to communication between terminals (for example, "side"). For example, terms such as an uplink channel and a downlink channel may be read as a side channel.

[0187] Similarly, the term "terminal" in the present disclosure may be read as "base station." In this case, the base station may be configured to have the functions of the terminal described above.

[0188] As used in this disclosure, the terms "determining" and "determining" may encompass a wide variety of actions. "Determining" and "determining" may include, for example, judging, calculating, computing, processing, deriving, investigating, looking up, searching, inquiring (e.g., searching in a table, database, or other data structure), ascertaining something as a "determination," and the like. Furthermore, "judgment" and "decision" may include regarding receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, and accessing (e.g., accessing data in memory) as having been "judgment" or "decision." Furthermore, "judgment" and "decision" may include regarding resolving, selecting, choosing, establishing, comparing, etc. as having been "judgment" or "decision." In other words, "judgment" and "decision" may include regarding some action as having been "judgment" or "decision." Furthermore, "judgment (decision)" may be interpreted as "assuming," "expecting," "considering," etc.

[0189] The terms "connected," "coupled," or any variation thereof, refer to any direct or indirect connection or coupling between two or more elements, and may include the presence of one or more intermediate elements between two elements that are "connected" or "coupled" to each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, "connected" may be read as "access." As used in this disclosure, two elements may be considered to be "connected" or "coupled" to each other using one or more wires, cables, and / or printed electrical connections, as well as electromagnetic energy having wavelengths in the radio frequency range, microwave range, and optical (both visible and invisible) range, as some non-limiting and non-exhaustive examples.

[0190] The reference signal may be abbreviated as RS (Reference Signal) or may be called a pilot depending on the applicable standard.

[0191] As used in this disclosure, the phrase "based on" does not mean "based only on," unless expressly stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

[0192] As used in this disclosure, any reference to an element using a designation such as "first," "second," etc. does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements. Thus, a reference to a first and a second element does not imply that only two elements may be employed or that the first element must in some way precede the second element.

[0193] The "means" in the configuration of each of the above devices may be replaced with "part," "circuit," "device," etc.

[0194] Where the terms "include," "including," and variations thereof are used in this disclosure, these terms are intended to be inclusive, similar to the term "comprising." Furthermore, the term "or," as used in this disclosure, is not intended to be an exclusive or.

[0195] A radio frame may be composed of one or more frames in the time domain. Each of the one or more frames in the time domain may be called a subframe. A subframe may further be composed of one or more slots in the time domain. A subframe may have a fixed time length (e.g., 1 ms) that is independent of numerology.

[0196] Numerology may be communication parameters that apply to the transmission and / or reception of a signal or channel, such as subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, radio frame structure, specific filtering operations performed by the transceiver in the frequency domain, specific windowing operations performed by the transceiver in the time domain, etc.

[0197] A slot may be composed of one or more symbols (such as an Orthogonal Frequency Division Multiplexing (OFDM) symbol or a Single Carrier Frequency Division Multiple Access (SC-FDMA) symbol) in the time domain. A slot may be a time unit based on numerology.

[0198] A slot may include multiple minislots. Each minislot may consist of one or multiple symbols in the time domain. A minislot may also be called a subslot. A minislot may consist of fewer symbols than a slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a minislot may be called PDSCH (or PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be called PDSCH (or PUSCH) mapping type B.

[0199] The radio frame, subframe, slot, minislot, and symbol all represent time units for transmitting signals, and may be referred to by other names corresponding to the radio frame, subframe, slot, minislot, and symbol.

[0200] For example, one subframe may be called a transmission time interval (TTI), a plurality of consecutive subframes may be called a TTI, or one slot or one minislot may be called a TTI. That is, at least one of the subframe and the TTI may be a subframe (1 ms) in existing LTE, a period shorter than 1 ms (for example, 1-13 symbols), or a period longer than 1 ms. Note that the unit representing the TTI may be called a slot, minislot, or the like instead of a subframe.

[0201] Here, TTI refers to, for example, the smallest time unit for scheduling in wireless communication. For example, in an LTE system, a base station performs scheduling to allocate wireless resources (such as frequency bandwidth and transmission power that can be used by each terminal 20) to each terminal 20 in TTI units. Note that the definition of TTI is not limited to this.

[0202] The TTI may be a transmission time unit for a channel-encoded data packet (transport block), a code block, a code word, etc., or may be a processing unit for scheduling, link adaptation, etc. When a TTI is given, the time interval (e.g., the number of symbols) to which a transport block, a code block, a code word, etc. is actually mapped may be shorter than the TTI.

[0203] When one slot or one minislot is called a TTI, one or more TTIs (i.e., one or more slots or one or more minislots) may be the minimum time unit for scheduling. Also, the number of slots (minislots) constituting the minimum time unit for scheduling may be controlled.

[0204] A TTI having a time length of 1 ms may be referred to as a regular TTI (TTI in LTE Rel. 8-12), normal TTI, long TTI, regular subframe, normal subframe, long subframe, slot, etc. A TTI shorter than a regular TTI may be referred to as a shortened TTI, short TTI, partial TTI (partial or fractional TTI), shortened subframe, short subframe, minislot, subslot, slot, etc.

[0205] In addition, a long TTI (e.g., a normal TTI, a subframe, etc.) may be interpreted as a TTI having a time length of more than 1 ms, and a short TTI (e.g., a shortened TTI, etc.) may be interpreted as a TTI having a TTI length shorter than the TTI length of a long TTI and greater than or equal to 1 ms.

[0206] A resource block (RB) is a resource allocation unit in the time domain and the frequency domain, and may include one or more consecutive subcarriers in the frequency domain. The number of subcarriers included in an RB may be the same regardless of the numerology, for example, 12. The number of subcarriers included in an RB may be determined based on the numerology.

[0207] The time domain of an RB may include one or more symbols and may have a length of one slot, one minislot, one subframe, or one TTI. One TTI, one subframe, etc. may each be composed of one or more resource blocks.

[0208] Note that one or more RBs may be referred to as a physical resource block (PRB), a subcarrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, or the like.

[0209] Furthermore, a resource block may be composed of one or more resource elements (REs). For example, one RE may be a radio resource region of one subcarrier and one symbol.

[0210] A Bandwidth Part (BWP) (which may also be referred to as a partial bandwidth) may represent a subset of contiguous common resource blocks (RBs) for a given numerology on a given carrier, where the common RBs may be identified by their index relative to a Common Reference Point of the carrier. PRBs may be defined in a BWP and numbered within the BWP.

[0211] The BWP may include a BWP for UL (UL BWP) and a BWP for DL ​​(DL BWP). One or more BWPs may be configured for a UE within one carrier.

[0212] At least one of the configured BWPs may be active, and the UE may not expect to transmit or receive a given signal / channel outside the active BWP. Note that the terms "cell," "carrier," etc. in this disclosure may be read as "BWP."

[0213] The above-described structures of radio frames, subframes, slots, minislots, symbols, etc. are merely examples, and various configurations may be used, such as the number of subframes included in a radio frame, the number of slots per subframe or radio frame, the number of minislots included in a slot, the number of symbols and RBs included in a slot or minislot, the number of subcarriers included in an RB, the number of symbols in a TTI, the symbol length, and the cyclic prefix (CP) length.

[0214] In this disclosure, where articles are added by translation, such as a, an, and the in English, the disclosure may include that the nouns following these articles are in the plural form.

[0215] In the present disclosure, the term "A and B are different" may mean "A and B are different from each other." The term may also mean "A and B are each different from C." Terms such as "separate" and "coupled" may also be interpreted in the same way as "different."

[0216] The aspects / embodiments described in this disclosure may be used alone, in combination, or switched depending on the implementation. Notification of predetermined information (e.g., notification that "X is true") is not limited to explicit notification, but may be implicit (e.g., not notifying the predetermined information).

[0217] In the present disclosure, an SS block or a CSI-RS is an example of a synchronization signal or a reference signal.

[0218] Although the present disclosure has been described in detail above, it is clear to those skilled in the art that the present disclosure is not limited to the embodiments described herein. The present disclosure can be implemented in modified and altered forms without departing from the spirit and scope of the present disclosure as defined by the claims. Therefore, the description of the present disclosure is intended to be illustrative and does not have any limiting meaning on the present disclosure.

[0219] REFERENCE SIGNS LIST 10 Base station 110 Transmitter 120 Receiver 130 Setting unit 140 Controller 20 Terminal 210 Transmitter 220 Receiver 230 Setting unit 240 Controller 1001 Processor 1002 Storage device 1003 Auxiliary storage device 1004 Communication device 1005 Input device 1006 Output device

Claims

1. a receiver for detecting a paging pre-notification signal; A control unit that performs paging monitoring based on the paging advance notification signal, The terminal, wherein the control unit skips monitoring at a paging occasion if the paging advance notification signal cannot be detected.

2. detecting a paging pre-notification signal; performing paging monitoring based on the paging advance notification signal; and skipping monitoring at the paging occasion if the paging pre-notification signal is not detected.

3. a transmitter for transmitting a paging advance notification signal; A control unit that assumes that a terminal performs paging monitoring based on the paging advance notification signal, If the terminal fails to detect the paging advance notification signal, monitoring at the paging occasion is skipped.

4. A communication system including a terminal and a base station, The terminal includes: a receiver for detecting a paging pre-notification signal; A control unit that performs paging monitoring based on the paging advance notification signal, The control unit skips monitoring at a paging occasion when the paging advance notification signal is not detected, The base station a transmitting unit for transmitting the paging advance notification signal to the terminal; A control unit that assumes that the terminal performs paging monitoring based on the paging advance notification signal.