Terminal and communication method

Abstract

This terminal includes: a reception unit whereby a notification from a base station constituting a non-terrestrial network (NTN) is received when a first condition is satisfied; and a transmission unit that transmits a signal to the base station when a second condition is satisfied. After the transmission unit transmits the signal to the base station, the reception unit receives information addressed to the terminal from the base station.

Description

Terminal and communication method

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

[0002] For NR (New Radio) (also known as "5G"), the successor system to LTE (Long Term Evolution), technologies are being considered that satisfy the requirements of a large-capacity system, high-speed data transmission speed, low latency, simultaneous connection of a large number of terminals, low cost, and low power consumption (for example, Non-Patent Document 1).

[0003] Currently, non-terrestrial networks (NTNs) are being considered, which use non-terrestrial networks such as satellites to provide services to areas that cannot be covered by terrestrial 5G networks, mainly due to cost considerations (e.g., Non-Patent Documents 2 and 3).

[0004] 3GPP TS 38.300 V17.6.0 (2023-09) 3GPP TR 38.821 V16.2.0 (2023-03) Konishi et al., "A Study on Downlink Spectrum Sharing in HAPS Mobile Communication Systems," IEICE General Conference, B-17-1, 2020

[0005] In NTN, the distance between the base station and the terminal in the sky is very large, and signal strength is significantly lower in a non-line-of-sight (NLOS) environment than in a line-of-sight (LOS) environment, which means that important paging information may not be received.

[0006] The present invention has been made in view of the above-mentioned points, and has as its object to improve reception performance in a wireless communication system when the communication environment is not good.

[0007] According to the disclosed technology, a terminal is provided which has a receiving unit that receives a notification from a base station that constitutes an NTN (Non-Terrestrial Network) when a first condition is satisfied, and a transmitting unit that transmits a signal to the base station when a second condition is satisfied, and after the transmitting unit transmits the signal to the base station, the receiving unit receives information addressed to the terminal from the base station.

[0008] According to the disclosed technology, it is possible to improve reception performance in a wireless communication system when the communication environment is not good.

[0009] FIG. 1 is a diagram showing an example (1) of NTN. FIG. 2 is a diagram showing an example (2) of NTN. FIG. 3 is a diagram showing an example (3) of NTN. FIG. 4 is a diagram showing an example (4) of NTN. FIG. 5 is a sequence diagram showing an example (1) of notification in NTN. FIG. 6 is a sequence diagram showing an example (2) of notification in NTN. FIG. 7 is a sequence diagram showing an example (3) of notification in NTN. FIG. 8 is a diagram showing an example of the functional configuration of a base station 10 in an embodiment of the present invention. FIG. 9 is a diagram showing an example of the functional configuration of a terminal 20 in an embodiment of the present invention. FIG. 10 is a diagram showing an example of the hardware configuration of a base station 10 or a terminal 20 in an embodiment of the present invention. FIG. 11 is a diagram showing an example of the configuration of a vehicle 2001 in an embodiment of the present invention.

[0010] 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.

[0011] In the operation of the wireless communication system according to the embodiment of the present invention, existing technology is used as appropriate. However, the existing technology is, for example, the existing LTE, but is not limited to the existing LTE. Furthermore, the term "LTE" used in this specification has a broad meaning including LTE-Advanced and systems subsequent to LTE-Advanced (e.g., NR), unless otherwise specified.

[0012] In addition, in the embodiments of the present invention described below, terms such as SS (Synchronization signal), PSS (Primary SS), SSS (Secondary SS), PBCH (Physical broadcast channel), PRACH (Physical random access channel), PDCCH (Physical Downlink Control Channel), PDSCH (Physical Downlink Shared Channel), PUCCH (Physical Uplink Control Channel), and PUSCH (Physical Uplink Shared Channel) used in existing LTE are used. This is for convenience of description, and similar signals, functions, etc. may be called by other names. In addition, the above-mentioned terms in NR correspond to NR-SS, NR-PSS, NR-SSS, NR-PBCH, NR-PRACH, NR-PDCCH, NR-PDSCH, NR-PUCCH, NR-PUSCH, etc. However, even if a signal is used in NR, it is not necessarily stated as "NR-".

[0013] Furthermore, in the embodiment of the present invention, the duplex method may be a time division duplex (TDD) method, a frequency division duplex (FDD) method, or another method (for example, flexible duplex, etc.).

[0014] Furthermore, in the embodiments of the present invention, "configuring" radio parameters etc. may mean that predetermined values ​​are pre-configured, or that radio parameters notified from the base station 10 or the terminal 20 are set.

[0015] FIG. 1 shows an example of an NTN (1). A Non-Terrestrial Network (NTN) uses non-terrestrial devices, such as satellites, to provide services to areas that cannot be covered by terrestrial 5G networks, primarily due to cost considerations. NTN can also provide more reliable services. For example, it is expected to be applied to IoT (Internet of Things), ships, buses, trains, and critical communications. NTN also has scalability through efficient multicast or broadcast.

[0016] As an example of an NTN, as shown in FIG. 1, a satellite 10A can retransmit signals transmitted from a terrestrial base station 10B to provide service to areas where terrestrial base stations are not located, such as mountainous regions.

[0017] The terrestrial 5G network may have the following configuration. The terrestrial 5G network includes one or more base stations 10 and terminals 20. The base station 10 is a communication device that provides one or more cells and performs wireless communication with the terminals 20. The physical resources of the 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. The base station 10 transmits a synchronization signal and system information to the terminals 20. The synchronization signal is, for example, NR-PSS and NR-SSS. The system information is transmitted, for example, via NR-PBCH, and is also called broadcast information.

[0018] 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). Both the base station 10 and the terminal 20 are capable of transmitting and receiving signals by performing beamforming. Furthermore, both the base station 10 and the terminal 20 are capable of applying MIMO (Multiple Input Multiple Output) communication to DL or UL. Furthermore, both the base station 10 and the terminal 20 may communicate via an SCell (Secondary Cell) and a PCell (Primary Cell) using CA (Carrier Aggregation).

[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, an M2M (Machine-to-Machine) communication module, etc. 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.

[0020] Figure 2 shows an example of an NTN (2). The area of ​​each cell or beam in an NTN is much larger than that of a terrestrial network (TN). Figure 2 shows an example of an NTN configured with retransmission by satellite. The connection between the satellite 10A and the NTN gateway 10B is called a feeder link, and the connection between the satellite 10A and the UE 20 is called a service link.

[0021] 2, the difference in delay between UE 20A on the near side and UE 20B on the far side is, for example, 10.3 ms in the case of GEO (Geosynchronous Orbit) and 3.2 ms in the case of LEO (Low Earth Orbit). Also, the beam size in NTN is, for example, 3500 km in the case of GEO and 1000 km in the case of LEO.

[0022] FIG. 3 is a diagram showing an example (3) of an NTN. As shown in FIG. 3, an NTN is realized by a satellite in space or a flying object in the air. For example, a GEO satellite may be a satellite located at an altitude of 35,786 km and having a geostationary orbit. For example, a LEO satellite may be a satellite located at an altitude of 500-2000 km and orbiting every 88-127 minutes. For example, a HAPS (High Altitude Platform Station) may be a flying object located at an altitude of 8-50 km and performing circular flight.

[0023] As shown in Figure 3, GEO satellites, LEO satellites, and HAPS aircraft may be connected to ground stations (gNBs) via gateways. The service areas may be larger in the order of HAPS, LEO, and GEO.

[0024] For example, NTN can extend the coverage of 5G networks to unserved or served areas. Furthermore, for example, NTN can improve the continuity, availability, and reliability of services on ships, buses, trains, or other critical communications. The NTN may be signaled by transmitting dedicated parameters to the terminal 20, and the dedicated parameters may be, for example, parameters related to determining a timing advance (TA) based on information related to satellites or aircraft.

[0025] Figure 4 is a diagram showing an example of an NTN (4). Figure 4 shows an example of an NTN network architecture assumed in the case of transparent payload. As shown in Figure 4, a CN (Core Network) 10D, a gNB 10C, and a gateway 10B are connected. The gateway 10B is connected to a satellite 10A via a feeder link. The satellite 10A is connected to a terminal 20A or a VSAT (Very Small Aperture Terminal) 20B via a service link. An NR Uu is established between the gNB 10C and the terminal 20A or the VSAT 20B.

[0026] Furthermore, the assumed network architecture of the NTN may employ FDD or may be capable of TDD. Terrestrial cells may be fixed or mobile. The terminal 20 may have the capability to support the Global Navigation Satellite System (GNSS). For example, a power class 3 handheld device may be assumed in FR1. At least in FR2, a VSAT device may be assumed.

[0027] The NTN network architecture may also assume regenerative payloads. For example, gNB functionality may be mounted on a satellite or air vehicle. Alternatively, a gNB-DU may be mounted on a satellite or air vehicle, and a gNB-CU may be deployed as a ground station.

[0028] In a non-terrestrial network (NTN), signal strength can be reduced by about 18 dB in a non-line-of-sight (NLOS) environment compared to a line-of-sight (LOS) environment. The probability of NLOS is estimated to be about 10% in suburban and rural environments and about 50% in urban environments.

[0029] Therefore, there is a risk that paging associated with the transmission of important information, such as ETWS (Earthquake and Tsunami Warning System) and VoIP (Voice over Internet Protocol), may not be received in an NLOS environment. Note that paging may refer to a signal that calls a terminal when a need arises on the network side to communicate with the terminal.

[0030] Therefore, a notification channel or a notification signal may be used as a signal to request a user to change location to a LOS environment so that paging can be received. For example, when a user cannot receive ETWS or VoIP-related paging in a NLOS environment, the user may receive the notification and then move to a new location to receive ETWS or VoIP-related paging. The configuration of the notification channel or the notification signal and the notification procedure may be determined.

[0031] The following describes the procedure or flow related to the notification, the configuration of the notification channel or the notification signal, and the information transmitted by the notification. Note that the embodiment of the present invention is not limited to application to NTN, and may be applied to a normal network, etc.

[0032] 5 is a sequence diagram showing an example (1) of notification in an NTN. In step S101, BS 10 transmits a cell-common notification to UE 20. In step S102, UE 20 executes reception of the cell-common notification if the conditions are met. The monitoring resources related to the reception may be cell-common between UEs. The monitoring resources may be set for each cell. Note that cell-common may mean common between UEs in the same cell. The same applies hereinafter.

[0033] In step S103, the UE 20 transmits a specific channel or signal to the BS 10. In step S104, the BS 10 transmits to the UE 20 information corresponding to the UE or information indicating that there is no data to transmit.

[0034] The condition in step S102 may be one or more of the following 1) to 4).

[0035] 1) Conditions related to RSRP (Reference signal received power). For example, if the RSRP of SSB and / or CSI-RS is lower than a defined, configured, or notified RSRP threshold, UE 20 may receive a notification common to the cell. Note that RSRP measurement may be performed based on signals other than SSB and / or CSI-RS. The same applies hereinafter.

[0036] 2) Conditions related to setting or notification: For example, when the BS 10 sets or notifies the UE 20 to perform reception, the UE 20 may receive the notification common to the cell.

[0037] 3) Conditions related to the timer. For example, if the timer expires, the UE 20 may perform reception of a cell-wide notification. When some signal (e.g., notification, paging, SIB, PDCCH, etc.) is received, the timer may be initialized and started or restarted.

[0038] 4) Conditions related to reception. For example, if UE 20 fails to receive any signal (e.g., paging, SIB, PDCCH, etc.) X times in succession, UE 20 may execute reception of a notification common to the cell. When any signal (e.g., notification, paging, SIB, PDCCH, etc.) is received, the counter indicating the number of receptions may be initialized and start counting again.

[0039] The conditions are not limited to 1)-4) above, but may be conditions related to communication conditions (e.g., conditions or notifications related to LOS / NLOS, conditions or notifications related to Doppler), or conditions related to NTN (e.g., conditions related to timing advance errors, conditions related to the UE position within the cell).

[0040] Furthermore, in step S103, when any one or more of the following conditions 1) to 4) are satisfied, the UE 20 may transmit a specific channel or signal to the BS 10. When the condition is satisfied, the channel condition may be improved from before.

[0041] 1) Condition related to RSRP. For example, if the RSRP of the SSB and / or CSI-RS exceeds a defined, configured, or notified RSRP threshold, the UE 20 may transmit the specific channel or signal to the BS 10. The RSRP threshold may be the same as or different from the RSRP threshold of the condition in step S102.

[0042] 2) Conditions related to setting or notification: For example, when the BS 10 sets or notifies the UE 20 to perform reception, i.e., when the UE 20 receives the setting or notification, the UE 20 may transmit the specific channel or signal to the BS 10.

[0043] 3) Conditions related to a timer: For example, a timer may be initialized and started when the notification is received in step S102, and when the timer expires, the UE 20 may transmit the particular channel or signal to the BS 10.

[0044] 4) Reception conditions: For example, if some signal is successfully received (e.g., notification, paging, SIB, PDCCH, etc., are successfully received X times in a row), the UE 20 may transmit the particular channel or signal to the BS 10.

[0045] The transmission of the particular channel or signal may be performed as shown in 1) or 2) below.

[0046] 1) For example, UE 20 may transmit one bit of information indicating improvement in channel conditions for data reception via periodic transmission opportunities (e.g., PRACH, configured PUCCH such as SR, configured SRS, configured PUSCH such as CG, etc.).

[0047] 2) For example, via PUCCH or PUSCH resources configured or dynamically notified by BS 10, UE 20 may transmit multi-bit information indicating channel conditions, UE speed, UE-ID (C-RNTI) and / or UE location, etc.

[0048] Note that any of the steps may not be executed, for example, step S103 may not be executed. Also, any of the steps may be replaced with a different operation, for example, step S103 may be replaced with the following operation: When the cell-wide notification is transmitted or received, a timer may be initialized and started in the BS 10 and the UE 20. After the timer expires, the UE 20 may attempt to receive corresponding information transmitted from the BS 10. The BS 10 may periodically transmit the information, such as ETWS or VoIP paging, regardless of whether the UE 20 receives the information.

[0049] Furthermore, the DRX ON period and / or sleep state of the UE 20 may be changed based on the reception of the notification and the corresponding transmission and reception. Note that DRX may mean discontinuous reception, and the sleep state may mean that the UE 20 does not receive a specific signal (e.g., a PDCCH for data scheduling).

[0050] The information indicating the absence of transmission data in step S104 may be 1-bit information via the DCI field or MAC-CE.

[0051] 6 is a sequence diagram showing an example (2) of notification in an NTN. In step S201, BS 10 transmits a group-wide notification to UE 20. In step S202, UE 20 executes reception of the group-wide notification if the conditions are met. The monitoring resources related to the reception may be cell-wide or group-wide between UEs. The monitoring resources may be set for each cell or for each UE group. Note that group-wide may mean that the resources are common between UEs in the same UE group in the same cell. The same applies hereinafter.

[0052] In step S203, the UE 20 transmits a specific channel or signal to the BS 10. In step S204, the BS 10 transmits to the UE 20 information corresponding to the UE or information indicating that there is no data to transmit.

[0053] The condition in step S202 may be one or more of the following 1) to 4).

[0054] 1) Conditions related to RSRP: For example, if the RSRP of the SSB and / or CSI-RS is lower than a defined, configured, or notified RSRP threshold, the UE 20 may receive a notification common to the group.

[0055] 2) Conditions related to setting or notification: For example, when the BS 10 sets or notifies the UE 20 to perform reception, the UE 20 may receive a notification common to the group.

[0056] 3) Conditions related to the timer. For example, when the timer expires, the UE 20 may perform reception of a group-wide notification. When some signal (e.g., notification, paging, SIB, PDCCH, etc.) is received, the timer may be initialized and started or restarted.

[0057] 4) Conditions related to reception. For example, if UE 20 fails to receive any signal (e.g., paging, SIB, PDCCH, etc.) X times in a row, UE 20 may execute reception of a notification common to the group. When any signal (e.g., notification, paging, SIB, PDCCH, etc.) is received, the counter indicating the number of receptions may be initialized and start counting again.

[0058] The conditions are not limited to 1)-4) above, but may be conditions related to communication conditions (e.g., conditions or notifications related to LOS / NLOS, conditions or notifications related to Doppler), or conditions related to NTN (e.g., conditions related to timing advance errors, conditions related to the UE position within the cell).

[0059] Furthermore, in step S203, when any one or more of the following conditions 1) to 4) are satisfied, the UE 20 may transmit a specific channel or signal to the BS 10. When the condition is satisfied, the channel condition may be improved from before.

[0060] 1) Condition related to RSRP. For example, if the RSRP of the SSB and / or CSI-RS exceeds a defined, configured, or notified RSRP threshold, the UE 20 may transmit the specific channel or signal to the BS 10. The RSRP threshold may be the same as or different from the RSRP threshold of the condition in step S202.

[0061] 2) Conditions related to setting or notification: For example, when the BS 10 sets or notifies the UE 20 to perform reception, i.e., when the UE 20 receives the setting or notification, the UE 20 may transmit the specific channel or signal to the BS 10.

[0062] 3) Conditions related to a timer: For example, a timer may be initialized and started when the notification is received in step S202, and when the timer expires, the UE 20 may transmit the particular channel or signal to the BS 10.

[0063] 4) Reception conditions: For example, if some signal is successfully received (e.g., notification, paging, SIB, PDCCH, etc., are successfully received X times in a row), the UE 20 may transmit the particular channel or signal to the BS 10.

[0064] The transmission of the particular channel or signal may be performed as shown in 1) or 2) below.

[0065] 1) For example, UE 20 may transmit one bit of information indicating improvement in channel conditions for data reception via periodic transmission opportunities (e.g., PRACH, configured PUCCH such as SR, configured SRS, configured PUSCH such as CG, etc.).

[0066] 2) For example, via PUCCH or PUSCH resources configured or dynamically notified by BS 10, UE 20 may transmit multi-bit information indicating channel conditions, UE speed, UE-ID (C-RNTI) and / or UE location, etc.

[0067] Note that any of the steps may not be executed, for example, step S203 may not be executed. Also, any of the steps may be replaced with a different operation, for example, step S203 may be replaced with the following operation: When the group-wide notification is transmitted or received, a timer may be initialized and started in the BS 10 and the UE 20. After the timer expires, the UE 20 may attempt to receive corresponding information transmitted from the BS 10. The BS 10 may periodically transmit the information, such as ETWS or VoIP paging, regardless of whether the UE 20 receives the information.

[0068] Additionally, the DRX ON period and / or sleep state of the UE 20 may be changed based on the receipt of the notification and the corresponding transmission and reception.

[0069] The information indicating the absence of transmission data in step S204 may be 1-bit information via the DCI field or MAC-CE.

[0070] 7 is a sequence diagram showing an example (3) of notification in an NTN. In step S301, the BS 10 transmits a UE-specific notification to the UE 20. In step S302, the UE 20 receives the UE-specific notification if a condition is met. The monitoring resources related to the reception may be common to all UEs, common to all groups, or individual to all UEs. The monitoring resources may be set for each cell, each UE group, or each UE.

[0071] In step S303, the UE 20 transmits a specific channel or signal to the BS 10. In step S304, the BS 10 transmits information corresponding to the UE to the UE 20.

[0072] The condition in step S302 may be one or more of the following 1) to 4).

[0073] 1) Conditions related to RSRP: For example, if the RSRP of the SSB and / or CSI-RS is lower than a defined, configured, or notified RSRP threshold, the UE 20 may receive a notification specific to that UE.

[0074] 2) Conditions related to setting or notification: For example, when the BS 10 sets or notifies the UE 20 to perform reception, the UE 20 may receive a notification specific to that UE.

[0075] 3) Conditions related to the timer. For example, when the timer expires, the UE 20 may receive a notification specific to the UE. When some signal (e.g., notification, paging, SIB, PDCCH, etc.) is received, the timer may be initialized and started or restarted.

[0076] 4) Conditions related to reception. For example, if UE 20 fails to receive any signal (e.g., paging, SIB, PDCCH, etc.) X times in a row, UE 20 may receive a notification dedicated to that UE. When any signal (e.g., notification, paging, SIB, PDCCH, etc.) is received, the counter indicating the number of times reception has occurred may be initialized and may start counting again.

[0077] The conditions are not limited to 1)-4) above, but may be conditions related to communication conditions (e.g., conditions or notifications related to LOS / NLOS, conditions or notifications related to Doppler), or conditions related to NTN (e.g., conditions related to timing advance errors, conditions related to the UE position within the cell).

[0078] Also, in step S303, when any one or more of the following conditions 1) to 4) are satisfied, the UE 20 may transmit a specific channel or signal to the BS 10. When the condition is satisfied, the channel condition may be improved from before.

[0079] 1) Condition related to RSRP. For example, if the RSRP of the SSB and / or CSI-RS exceeds a defined, configured, or notified RSRP threshold, the UE 20 may transmit the specific channel or signal to the BS 10. The RSRP threshold may be the same as or different from the RSRP threshold of the condition in step S302.

[0080] 2) Conditions related to setting or notification: For example, when the BS 10 sets or notifies the UE 20 to perform reception, i.e., when the UE 20 receives the setting or notification, the UE 20 may transmit the specific channel or signal to the BS 10.

[0081] 3) Conditions related to a timer: For example, a timer may be initialized and started when the notification is received in step S302, and when the timer expires, the UE 20 may transmit the particular channel or signal to the BS 10.

[0082] 4) Reception conditions: For example, if some signal is successfully received (e.g., notification, paging, SIB, PDCCH, etc., are successfully received X times in a row), the UE 20 may transmit the particular channel or signal to the BS 10.

[0083] The transmission of the particular channel or signal may be performed as shown in 1) or 2) below.

[0084] 1) For example, UE 20 may transmit one bit of information indicating improvement in channel conditions for data reception via periodic transmission opportunities (e.g., PRACH, configured PUCCH such as SR, configured SRS, configured PUSCH such as CG, etc.).

[0085] 2) For example, via PUCCH or PUSCH resources configured or dynamically notified by BS 10, UE 20 may transmit multi-bit information indicating channel conditions, UE speed, UE-ID (C-RNTI) and / or UE location, etc.

[0086] Note that any of the steps may not be executed, for example, step S303 may not be executed. Also, any of the steps may be replaced with a different operation, for example, step S303 may be replaced with the following operation: When the UE-specific notification is transmitted or received, a timer may be initialized and started in the BS 10 and the UE 20. After the timer expires, the UE 20 may attempt to receive corresponding information transmitted from the BS 10. The BS 10 may periodically transmit the information, such as ETWS or VoIP paging, regardless of whether the UE 20 receives the information.

[0087] Additionally, the DRX ON period and / or sleep state of the UE 20 may be changed based on the receipt of the notification and the corresponding transmission and reception.

[0088] The notification or notification information transmitted from BS 10 to UE 20 in step S101, step S201, or step S301 may be a channel and / or signal having the configuration shown in 1)-4) below. Note that the channel and / or signal having such a configuration may be a signal that is easier to receive in UE 20 than a normal downlink signal.

[0089] 1) A signal with a configuration similar to that of the PUCCH. For example, periodic opportunities may be set, and the notification signal may be transmitted at any of the opportunities. The UE may monitor the opportunities in step S102, step S202, or step S302. Information specifying resources within a slot and a period may be set. Also, for example, the signal format may be the same as or similar to PUCCH format 0, 1, or 3.

[0090] For example, if a signal format is the same as or similar to PUCCH format 0, a base sequence and cyclic shift may be used, and a specific cyclic shift may be used for the signaling. The format may signal one or two bits. No channel coding may be applied.

[0091] For example, in the case of a signal format identical or similar to PUCCH format 1, a base sequence, a signal modulated by BPSK (Binary Phase Shift Keying) or QPSK (Quadrature Phase Shift Keying), and a DMRS may be used. The notification may be carried by multiple symbols that are copies of a symbol modulated by BPSK or QPSK using the base sequence. The DMRS and the notification information may be mapped alternately in the time domain. The format may signal one or two bits. Channel coding may not be applied.

[0092] For example, when a signal format is the same as or similar to PUCCH format 3, a BPSK, QPSK, or 16QAM (Quadrature amplitude modulation) modulated signal and DMRS may be used. The format may carry three or more bits. Channel coding may be applied.

[0093] 2) Sequence-based signaling. For example, periodic opportunities may be set, and the notification signal may be transmitted at any of the opportunities. The UE may monitor the opportunities in step S102, step S202, or step S302. Information specifying resources within a slot and the period may be set.

[0094] For example, a sequence may be transmitted from the BS 10, and the sequence detected by the UE 20 may be mapped to the signaling information received. This mapping may be configured via a common signal or a UE-specific signal. For example, an RS may be defined, configured, or signaled for the signaling information. For example, one or more bits may be carried by the sequence-based signal. The sequence length may be N (e.g., N=12), where N may be defined or configured. Channel coding may not be applied.

[0095] 3) PDCCH and DCI with fewer bits may be used. For example, a new DCI format may be defined or configured for the notification information. The new DCI format may or may not accompany other information. For example, a UE specific search space (USS) may be used in step S301, and a common search space (CSS) may be used in step S101.

[0096] For example, when a PDCCH and a DCI are monitored, other specific PDCCHs and DCIs may not be monitored, such as DCIs with CRCs scrambled with a P-RNTI.

[0097] A separate RNTI may be defined or configured for the signaling information. Configurations for monitoring search space, CORESET, etc. may be provided by the network. Channel coding (e.g., Reed-Muller code) with a small payload size, e.g., up to 11 bits, may be applied, and CRC bits may not be added. DCI size adjustment may not be applied to the new DCI format. The DCI size budget (up to four (3 for C-RNTI + 1 for non-C-RNTI)) restriction may not be applied to the new DCI format.

[0098] 4) The notification information may be notified in one bit using a spare bit included in the MIB.

[0099] The notification or notification information transmitted from the BS 10 to the UE 20 in step S101, step S201 or step S301 may include the information shown in 1)-4) below.

[0100] 1) A single-bit notification may be used. For example, in step S101, the same notification may be received by all UEs in a certain cell. For example, in step S201, transmission resources may be divided among UE groups. For example, in step S301, transmission resources may be divided among UEs.

[0101] 2) The notification may include target identification information. For example, in step S201, information indicating which UE group the notification targets may be included in the notification. For example, in step S301, information indicating which UE the notification targets may be included in the notification. To identify the UE group, a UE group ID may be set in each UE and notified via the notification. Also, to identify the UE group, a part of the C-RNTI may be notified via the notification. Also, to identify the UE, a UE-ID may be set and notified via the notification. Also, to identify the UE, a C-RNTI may be notified via the notification.

[0102] 3) Information indicating which channels and / or signals are to be received may be transmitted, e.g., specific SIBs for reception may be explicitly signaled, or specific SIBs for reception may be associated with signaling resources, for example.

[0103] 4) Information related to subsequent reception operations may be transmitted. For example, information indicating when corresponding information is to be transmitted, such as timing, period, etc., may be transmitted. For example, information indicating when the UE has completed the improvement of the channel condition and should transmit information indicating the completion of the improvement of the channel condition and / or receive corresponding information (ETWS, VoIP paging, etc.) may be transmitted, and a timer for performing the operations may be notified.

[0104] The following UE capabilities may be defined and reported from the UE 20 to the BS 10: Whether or not the reception of the notification is supported; Whether or not one or more specific conditions in step S102, S202 or S302 are supported; Whether or not one or more specific conditions in step S103, S203 or S303 are supported; Whether or not the reporting in step S103, S203 or S303 is supported; Which types of channels and / or signals are supported for receiving the notification.

[0105] The above-described embodiment allows the terminal 20 to receive important messages based on the notification message. The sequence shown in Fig. 5 allows performance to be improved by using a simple notification message. The sequence shown in Fig. 7 allows the notification message to be sent only to the target UE, thereby avoiding unnecessary or undesired reception. The sequence shown in Fig. 6 allows a balance to be set regarding the performance of the sequences shown in Figs. 5 and 7. Subsequent actions can be triggered based on improvement in channel conditions. The base station 10 can decide whether to perform the subsequent actions. Using existing channels and / or signals for the notification can facilitate implementation.

[0106] Furthermore, according to the above-described embodiment, the base station 10 can urge the terminal 20 to improve the reception environment and transmit important data to the terminal 20 by transmitting a notification signal that has a high probability of successful reception even in an NLOS environment to the terminal 20.

[0107] That is, in a wireless communication system, it is possible to improve reception performance when the communication environment is not good.

[0108] (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 embodiments. However, the base station 10 and the terminal 20 may each include only a part of the functions of the embodiments.

[0109] <Base Station 10> Figure 8 is a diagram showing an example of the functional configuration of the base station 10 according to the embodiment of the present invention. As shown in Figure 8, 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 Figure 8 is merely an example. The names of the functional divisions and functional units may be any as long as they can perform the operations according to the embodiment of the present invention.

[0110] The transmitter 110 has a function of generating a signal to be transmitted to the terminal 20 side and transmitting the signal wirelessly. The transmitter 110 also transmits inter-network node messages to other network nodes. The receiver 120 has a function of receiving various signals transmitted from the terminal 20 and acquiring, for example, information of higher layers from the received signals. The transmitter 110 also has a function of transmitting NR-PSS, NR-SSS, NR-PBCH, DL / UL control signals, etc. to the terminal 20. The receiver 120 also receives inter-network node messages from other network nodes.

[0111] The setting unit 130 stores preset setting information and various setting information to be transmitted to the terminal 20. The setting information includes, for example, information related to communication in the NTN.

[0112] As described in the embodiments, the control unit 140 controls communication in the NTN. The control unit 140 also controls communication with the terminal 20 based on a UE capability report regarding radio parameters received from the terminal 20. A functional unit related to signal transmission in the control unit 140 may be included in the transmitting unit 110, and a functional unit related to signal reception in the control unit 140 may be included in the receiving unit 120.

[0113] <Terminal 20> Fig. 9 is a diagram showing an example of the functional configuration of terminal 20 in an embodiment of the present invention. As shown in Fig. 9, 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. 9 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.

[0114] The transmitter 210 creates a transmission signal from transmission data and transmits the transmission signal wirelessly. The receiver 220 wirelessly receives various signals and acquires higher layer signals from the received physical layer signals. The receiver 220 also has a function of receiving NR-PSS, NR-SSS, NR-PBCH, DL / UL / SL control signals, and the like transmitted from the base station 10. For example, the transmitter 210 transmits a PSCCH (Physical Sidelink Control Channel), a PSSCH (Physical Sidelink Shared Channel), a PSDCH (Physical Sidelink Discovery Channel), a PSBCH (Physical Sidelink Broadcast Channel), and the like to another terminal 20 as D2D communication, and the receiver 120 receives the PSCCH, PSSCH, PSDCH, or PSBCH, and the like, from the other terminal 20.

[0115] The setting unit 230 stores various setting information received from the base station 10 by the receiving unit 220. The setting unit 230 also stores setting information that is set in advance. The content of the setting information is, for example, information related to communication in the NTN.

[0116] As described in the embodiments, the control unit 240 controls communications in the NTN. The signal transmission functional unit in the control unit 240 may be included in the transmitting unit 210, and the signal reception functional unit in the control unit 240 may be included in the receiving unit 220.

[0117] (Hardware Configuration) The block diagrams (FIGS. 8 and 9) 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.

[0118] Functions include, but are not limited to, judgment, determination, assessment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, selection, 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 mentioned above, there are no particular limitations on how these functions are implemented.

[0119] 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. 10 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.

[0120] 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.

[0121] 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.

[0122] 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.

[0123] The processor 1001 also 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. 8 may be implemented by a control program stored in the storage device 1002 and running on the processor 1001. For example, the control unit 240 of the terminal 20 shown in FIG. 9 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.

[0124] The storage device 1002 is a computer-readable recording medium and may be configured, for example, by at least one of a read-only memory (ROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a random access memory (RAM), 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.

[0125] The secondary storage device 1003 is a computer-readable recording medium, and may be, 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 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.

[0126] 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, a communication module, etc. 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.

[0127] 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).

[0128] 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.

[0129] 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.

[0130] Fig. 11 shows an example configuration of a vehicle 2001. As shown in Fig. 11, the vehicle 2001 includes a drive unit 2002, a steering unit 2003, an accelerator pedal 2004, a brake pedal 2005, a shift lever 2006, front wheels 2007, rear wheels 2008, an axle 2009, an electronic control unit 2010, various sensors 2021 to 2029, an information service unit 2012, and a communication module 2013. Each aspect / embodiment described in the present disclosure may be applied to a communication device mounted on the vehicle 2001, and may be applied to the communication module 2013, for example.

[0131] The drive unit 2002 is configured, for example, by an engine, a motor, or a hybrid of an engine and a motor. The steering unit 2003 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 the user.

[0132] The electronic control unit 2010 is composed of a microprocessor 2031, a memory (ROM, RAM) 2032, and a communication port (IO port) 2033. Signals are input to the electronic control unit 2010 from various sensors 2021 to 2029 provided in the vehicle 2001. The electronic control unit 2010 may also be called an ECU (Electronic Control Unit).

[0133] The signals from the various sensors 2021 to 2029 include a current signal from a current sensor 2021 that senses the current of the motor, a front or rear wheel rotation speed signal obtained by a rotation speed sensor 2022, a front or rear wheel air pressure signal obtained by an air pressure sensor 2023, a vehicle speed signal obtained by a vehicle speed sensor 2024, an acceleration signal obtained by an acceleration sensor 2025, an accelerator pedal depression amount signal obtained by an accelerator pedal sensor 2029, a brake pedal depression amount signal obtained by a brake pedal sensor 2026, a shift lever operation signal obtained by a shift lever sensor 2027, and a detection signal for detecting obstacles, vehicles, pedestrians, etc. obtained by an object detection sensor 2028.

[0134] The information service unit 2012 is composed of various devices, such as a car navigation system, an audio system, speakers, a television, and a radio, for providing (outputting) 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 2012 uses information acquired from external devices via the communication module 2013 or the like to provide various types of multimedia information and multimedia services to the occupants of the vehicle 2001. The information service unit 2012 may include input devices (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, a touch panel, etc.) that accept input from the outside, and may also include output devices (e.g., a display, a speaker, an LED lamp, a touch panel, etc.) that output information to the outside.

[0135] The driving assistance system unit 2030 is composed of various devices that provide functions for preventing accidents and reducing the driving burden on the driver, 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 2030 transmits and receives various information via the communication module 2013 to realize the driving assistance function or the autonomous driving function.

[0136] The communication module 2013 can communicate with the microprocessor 2031 and components of the vehicle 2001 via the communication port. For example, the communication module 2013 transmits and receives data via the communication port 2033 to and from the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, front wheels 2007, rear wheels 2008, axle 2009, microprocessor 2031 and memory (ROM, RAM) 2032 in the electronic control unit 2010, and sensors 2021 to 29, which are provided in the vehicle 2001.

[0137] The communication module 2013 is a communication device that can be controlled by the microprocessor 2031 of the electronic control unit 2010 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 2013 may be located either inside or outside the electronic control unit 2010. The external device may be, for example, a base station, a mobile station, or the like.

[0138] The communication module 2013 may transmit at least one of signals from the above-mentioned various sensors 2021-2028 input to the electronic control unit 2010, information obtained based on the signals, and information based on input from the outside (user) obtained via the information service unit 2012 to an external device via wireless communication. The electronic control unit 2010, the various sensors 2021-2028, the information service unit 2012, etc. may be referred to as input units that accept input. For example, the PUSCH transmitted by the communication module 2013 may include information based on the above-mentioned input.

[0139] The communication module 2013 receives various information (traffic information, traffic signal information, vehicle-to-vehicle information, etc.) transmitted from external devices and displays it on an information service unit 2012 provided in the vehicle 2001. The information service unit 2012 may be called an output unit that outputs information (for example, outputs information to a device such as a display or speaker based on the PDSCH (or data / information decoded from the PDSCH) received by the communication module 2013). The communication module 2013 also stores the various information received from external devices in a memory 2032 that can be used by the microprocessor 2031. Based on the information stored in the memory 2032, the microprocessor 2031 may control the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, front wheels 2007, rear wheels 2008, axles 2009, sensors 2021 to 2029, etc. provided in the vehicle 2001.

[0140] (Summary of the embodiment) As described above, according to the embodiment of the present invention, a terminal is provided which has a receiving unit that receives a notification from a base station that constitutes an NTN (Non-Terrestrial Network) when a first condition is satisfied, and a transmitting unit that transmits a signal to the base station when a second condition is satisfied, and after the transmitting unit transmits the signal to the base station, the receiving unit receives information addressed to the terminal from the base station.

[0141] With the above configuration, the base station 10 can transmit to the terminal 20 a notification signal that has a high probability of successful reception even in an NLOS environment, thereby urging the terminal 20 to improve the reception environment and transmitting important data to the terminal 20. That is, in a wireless communication system, it is possible to improve reception performance when the communication environment is not good.

[0142] 2. The terminal according to claim 1, wherein the first condition is that RSRP (Reference signal received power) of a synchronization signal or a reference signal transmitted from the base station is below a threshold, and the second condition is that RSRP of the synchronization signal or the reference signal transmitted from the base station is above a threshold. With this configuration, the base station 10 can urge the terminal 20 to improve the reception environment and transmit important data to the terminal 20 by transmitting a notification signal with a high probability of successful reception even in a non-linear out-of-band (NLOS) environment.

[0143] The first condition may be that a timer that is initialized and started upon receiving some signal has expired, and the second condition may be that a timer that is initialized and started upon receiving the notification has expired. With this configuration, the base station 10 can urge the terminal 20 to improve the reception environment and transmit important data to the terminal 20 by transmitting a notification signal that has a high probability of successful reception even in an NLOS environment to the terminal 20.

[0144] The notification may be transmitted to a cell in general, a UE (User Equipment) group in general, or to an individual UE. With this configuration, the base station 10 can urge the terminal 20 to improve the reception environment and transmit important data to the terminal 20 by transmitting a notification signal with a high probability of successful reception even in a non-linear outage environment.

[0145] After the transmitting unit transmits the signal to the base station, the receiving unit may receive information from the base station indicating that there is no information addressed to the base station. With this configuration, the base station 10 can urge the terminal 20 to improve the reception environment and transmit important data to the terminal 20 by transmitting a notification signal with a high probability of successful reception even in a non-linear out-of-band (NLOS) environment to the terminal 20.

[0146] Furthermore, according to an embodiment of the present invention, there is provided a communication method in which a terminal executes the following procedures: when a first condition is satisfied, receiving a notification from a base station that constitutes an NTN (Non-Terrestrial Network); when a second condition is satisfied, transmitting a signal to the base station; and, after transmitting the signal to the base station, receiving information addressed to the terminal from the base station.

[0147] With the above configuration, the base station 10 can transmit to the terminal 20 a notification signal that has a high probability of successful reception even in an NLOS environment, thereby urging the terminal 20 to improve the reception environment and transmitting important data to the terminal 20. That is, in a wireless communication system, it is possible to improve reception performance when the communication environment is not good.

[0148] (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.

[0149] Furthermore, the notification of information is not limited to the aspects / embodiments described in the present 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), 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), 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, an RRC Connection Reconfiguration message, or the like.

[0150] Each aspect / embodiment described in the present disclosure may be applied to at least one of systems using LTE (Long Term Evolution), LTE-Advanced (LTE-A), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication system), 5G (5th generation mobile communication system), FRA (Future Radio Access), NR (New Radio), 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 802.20, UWB (Ultra-Wide Band), Bluetooth (registered trademark), or other suitable systems, and next-generation systems enhanced based on these. Furthermore, a combination of multiple systems (e.g., a combination of at least one of LTE and LTE-A with 5G, etc.) may also be applied.

[0151] 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.

[0152] 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).

[0153] 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.

[0154] 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 transmitted to another device.

[0155] 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).

[0156] 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.

[0157] 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.

[0158] 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.

[0159] 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.

[0160] As used in this disclosure, the terms "system" and "network" are used interchangeably.

[0161] Furthermore, the information, parameters, etc. described in the present disclosure may be expressed using absolute values, relative values ​​from a predetermined value, or other corresponding information. For example, a radio resource may be indicated by an index.

[0162] 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., 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.

[0163] In the present disclosure, terms such as "base station (BS)," "radio base station," "base station device," "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.

[0164] 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 small indoor base station (RRH: Remote Radio Head)). The terms "cell" or "sector" refer to part or all of the coverage area of ​​a base station and / or base station subsystem that provides communication services within that coverage.

[0165] In the present disclosure, the base station transmitting information to a terminal may be interpreted as the base station instructing the terminal to control or operate based on the information.

[0166] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," and the like may be used interchangeably.

[0167] 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, wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable terminology.

[0168] 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 object, the mobile object itself, etc. The mobile object refers to a movable object, and may move at any speed. Naturally, this also includes cases where the mobile object is stationary. Examples of the mobile object include, but are not limited to, vehicles, transport vehicles, automobiles, motorcycles, bicycles, connected cars, excavators, bulldozers, wheel loaders, dump trucks, forklifts, trains, buses, handcars, rickshaws, ships and other watercraft, airplanes, rockets, satellites, drones (registered trademark), multicopters, quadcopters, balloons, and objects mounted thereon. The mobile object may also be a mobile object that moves autonomously based on an operational command. It may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile object (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 be a device that does 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.

[0169] Furthermore, a base station in the present disclosure may be read as a user terminal. For example, the aspects / embodiments of the present disclosure may be applied to a configuration in which communication between a base station and a user terminal is replaced with communication between multiple terminals 20 (which may be called, for example, Device-to-Device (D2D) or Vehicle-to-Everything (V2X)). 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 terminal-to-terminal communication (for example, "side"). For example, terms such as an uplink channel and a downlink channel may be read as a side channel.

[0170] Similarly, the user terminal in the present disclosure may be read as a base station, in which case the base station may be configured to have the functions of the user terminal described above.

[0171] 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, and the like. "Determining" and "determining" may also include receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in memory), and the like. Furthermore, "judgment" and "decision" can include regarding resolving, selecting, choosing, establishing, comparing, etc. as having been "judged" or "decided." In other words, "judgment" and "decision" can include regarding some action as having been "judged" or "decided." Furthermore, "judgment (decision)" can be interpreted as "assuming," "expecting," "considering," etc.

[0172] 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.

[0173] The reference signal may be abbreviated as RS (Reference Signal) or may be called a pilot depending on the applicable standard.

[0174] 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."

[0175] 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.

[0176] The "means" in the configuration of each of the above devices may be replaced with "part," "circuit," "device," etc.

[0177] When 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, when the term "or" is used in this disclosure, it is not intended to be an exclusive or.

[0178] 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.

[0179] 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.

[0180] 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.

[0181] 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.

[0182] 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.

[0183] For example, one subframe may be called a transmission time interval (TTI), multiple 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, etc. instead of a subframe.

[0184] 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.

[0185] 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.

[0186] 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.

[0187] A TTI having a time length of 1 ms may be called 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 called a shortened TTI, short TTI, partial or fractional TTI, shortened subframe, short subframe, minislot, subslot, slot, etc.

[0188] 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.

[0189] 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.

[0190] 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.

[0191] Note that one or more RBs may also be called a physical resource block (PRB), a sub-carrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, etc.

[0192] 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.

[0193] A Bandwidth Part (BWP) (which may also be referred to as a fractional 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.

[0194] 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.

[0195] 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."

[0196] The above-described structures of radio frames, subframes, slots, minislots, symbols, etc. are merely examples, and various changes may be made to 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, the cyclic prefix (CP) length, etc.

[0197] 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.

[0198] 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."

[0199] 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).

[0200] 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.

[0201] 10 Base station 110 Transmitter 120 Receiver 130 Setting unit 140 Control unit 20 Terminal 210 Transmitter 220 Receiver 230 Setting unit 240 Control unit 1001 Processor 1002 Storage device 1003 Auxiliary storage device 1004 Communication device 1005 Input device 1006 Output device 2001 Vehicle 2002 Drive unit 2003 Steering unit 2004 Accelerator pedal 2005 Brake pedal 2006 Shift lever 2007 Front wheels 2008 Rear wheels 2009 Axle 2010 Electronic control unit 2012 Information service unit 2013 Communication module 2021 Current sensor 2022 Rotation speed sensor 2023 Tire pressure sensor 2024 Vehicle speed sensor 2025 Acceleration sensor 2026 Brake pedal sensor 2027 Shift lever sensor 2028 Object detection sensor 2029 Accelerator pedal sensor 2030 Driving assistance system unit 2031 Microprocessor 2032 Memory (ROM, RAM) 2033 Communication port (IO port)

Claims

1. When the first condition is satisfied, it has a receiving unit that receives a notification from a base station constituting an NTN (Non-Terrestrial Network), and when the second condition is satisfied, it has a transmitting unit that transmits a signal to the base station. After the transmitting unit transmits the signal to the base station, the receiving unit receives information addressed to the own device from the base station.

2. The first condition is that the RSRP (Reference signal received power) of a synchronization signal or a reference signal transmitted from the base station is below a threshold value, and the second condition is that the RSRP of a synchronization signal or a reference signal transmitted from the base station is above a threshold value. The terminal according to claim 1.

3. The first condition is that a timer initialized and started when any signal is received expires, and the second condition is that a timer initialized and started when the notification is received expires. The terminal according to claim 1.

4. The notification is transmitted cell-common, UE (User Equipment) group-common, or UE-individually. The terminal according to claim 1.

5. After the transmitting unit transmits the signal to the base station, the receiving unit receives information indicating that there is no information addressed to the own device from the base station. The terminal according to claim 1.

6. A communication method in which a terminal executes a procedure of receiving a notification from a base station constituting an NTN (Non-Terrestrial Network) when the first condition is satisfied, a procedure of transmitting a signal to the base station when the second condition is satisfied, and a procedure of receiving information addressed to the own device from the base station after transmitting the signal to the base station.

Images