Terminal and communication method
By incorporating a receiving unit and control unit to prioritize reception, RedCap and eRedCap terminals can efficiently connect to NTNs, addressing the challenge of simultaneous UL and DL limitations in system information acquisition.
Patent Information
- Application Number
- PCT/JP2024/014871
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-04-12
- Publication Date
- 2025-10-16
AI Technical Summary
Existing terminals with reduced functionality, such as RedCap and eRedCap devices, face challenges in connecting to Non-Terrestrial Networks (NTNs) due to limitations in simultaneous UL transmission and DL reception, necessitating a method to prioritize reception during system information acquisition.
A terminal with reduced functionality is equipped with a receiving unit for acquiring necessary system information and a control unit that determines whether to prioritize transmission or reception, optimizing the connection process to NTNs.
Enables RedCap and eRedCap terminals to effectively connect to NTNs by prioritizing reception during specific opportunities, ensuring reliable system information acquisition and network connectivity.
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Figure JP2024014871_16102025_PF_FP_ABST
Abstract
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] In addition, in LTE or NR, UE categories or UE capabilities for IoT (Internet of Things) are defined that reduce functions that are mandatory for normal terminals, such as functions related to transmission and reception bandwidth and the number of antennas. For example, in LTE, eMTC (enhanced Machine Type Communication) and NB-IoT (Narrow Band IoT) are defined, and in NR, RedCap (Reduced Capability) and the like are defined.
[0005] 3GPP TS 38.300 V18.0.0 (2023-12) 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 3GPP TS 38.331 V18.0.0 (2023-12)
[0006] In future systems (e.g., NR Release 18 and 6G, the successor system to NR), eRedCap (enhanced Reduced Capability), which has even fewer functions than RedCap considered in NR Release 17, is being considered. For example, a RedCap terminal or eRedCap terminal may not support simultaneous UL transmission and DL reception. On the other hand, in order to connect to an NTN, it is necessary to acquire specific system information, and therefore it is necessary to determine whether UL transmission or DL reception should be prioritized.
[0007] The present invention has been made in view of the above points, and has as its object to enable a terminal with reduced functionality to connect to an NTN (Non-Terrestrial Network) in a wireless communication system.
[0008] According to the disclosed technology, in an NTN (Non-Terrestrial Network), a terminal is provided which has a receiving unit that receives system information necessary to connect to the NTN, and a control unit that determines whether to prioritize transmission or reception, and the control unit prioritizes reception during some of the opportunities to receive the system information.
[0009] According to the disclosed technology, in a wireless communication system, a terminal with reduced functionality can connect to an NTN (Non-Terrestrial Network).
[0010] 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 diagram showing an example of RedCap. FIG. 6 is a diagram showing an example of SIB acquisition in an embodiment of the present invention. FIG. 7 is a flowchart for explaining an example of SIB acquisition in an embodiment of the present invention. 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.
[0011] 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.
[0012] 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.
[0013] 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-".
[0014] 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.).
[0015] 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.
[0016] 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.
[0017] 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.
[0018] 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.
[0019] 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).
[0020] 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.
[0021] 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.
[0022] 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.
[0023] 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.
[0024] 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.
[0025] 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.
[0026] 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.
[0027] 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.
[0028] 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.
[0029] Figure 5 is a diagram showing an example of RedCap. As shown in Figure 5, RedCapUE is defined in NR Release 17, and eRedCapUE is defined in NR Release 18. RedCapUE has performance and complexity intermediate between that of a regular NR device and an LTE IoT device. RedCapUE may support bandwidths up to 20 MHz and communication speeds up to 150 Mbps. eRedCapUE may support bandwidths up to 5 MHz and communication speeds up to 10 Mbps.
[0030] First, we will explain the RedCap of the conventional NR Release 17. The maximum bandwidth supported by the RedCapUE considered in NR Release 17 is 20 MHz in FR1 (Frequency Range 1) and 100 MHz in FR2 (Frequency Range 2). In addition, RedCapUE is required to coexist with non-RedCapUE (hereinafter also referred to as "non-RedCapUE") within the system.
[0031] In addition, RedCap UE and non-RedCap UE may be able to share the same initial DL-BWP (Downlink Bandwidth part) (including subcarrier spacing, bandwidth, and location) set by the MIB (Master Information Block), while an initial DL-BWP with separate or additional subcarrier spacing, bandwidth, and location may be set for the RedCap UE.
[0032] RedCapUEs can share the initial DL-BWP (hereinafter also referred to as "DL-BWP#0") for non-RedCapUEs if the maximum bandwidth supported by the RedCapUE is not exceeded.
[0033] In addition, in the NR Release 17 specifications, in order to avoid RF retuning, in the case of TDD, the DL-BWP and UL-BWP of the same index must have the same center frequency.
[0034] Also, after establishing or re-establishing a dedicated RRC connection, the RedCapUE assumes that the initial DL-BWP and active DL-BWP are less than or equal to the maximum DL bandwidth supported by the RedCapUE. The RedCapUE is provided with a DL-BWP by "initialDownlinkBWP" in "DownlinkConfigCommonRedCapSIB" and a UL-BWP by "initialUplinkBWP" in "UplinkConfigCommonRedCapSIB". If the "initialUplinkBWP" in "UplinkConfigCommonSIB" indicates a UL-BWP greater than the maximum UL-BWP supported by the RedCapUE, the RedCapUE assumes that the UL-BWP is provided by "initialUplinkBWP" in "UplinkConfigCommonRedCapSIB".
[0035] A RedCapUE may be provided with a DL-BWP by "BWP-DownlinkDedicated" in addition to the initial DL-BWP. A RedCapUE may be provided with a UL-BWP by "BWP-UplinkDedicated" in addition to the initial UL-BWP, which is less than the maximum UL bandwidth supported by the RedCapUE.
[0036] If the RedCapUE is provided with "RACH-ConfigCommon-RedCap" or "RACH-ConfigCommonTwoStepRA-RedCap", the RedCapUE uses the corresponding parameters to perform the initial access and random access procedures. Otherwise, the RedCapUE uses the corresponding parameters provided by "RACH-ConfigCommon" or "RACH-ConfigCommonTwoStepRA".
[0037] If a RedCapUE is provided with "initialUplinkBWP" in "UplinkConfigCommonRedCapSIB" and has no dedicated PUCCH resource configuration, it will use the PUCCH resource set provided by "pucch-ResourceCommonRedCap" to transmit PUCCH using HARQ-ACK information. Note that if "disable-FH-PUCCH" is provided in "PUCCH-ConfigCommonRedCap", PUCCH transmission will be disabled.
[0038] For the initial DL-BWP provided by "initialDownlinkBWP" in "DownlinkConfigCommonRedCapSIB", if the RedCapUE monitors the PDCCH according to the CSS (Common search space) set of Type1-PDCCH and does not monitor the PDCCH according to the CSS set of Type2-PDCCH, it recognizes that the initial DL-BWP does not contain an SS / PBCH block or a CORESET (Control resource set) with index 0.
[0039] When a RedCapUE monitors the PDCCH according to the CSS set of Type2-PDCCH, it is assumed that the initial DL-BWP includes the SS / PBCH block and a CORESET with index 0 if the RedCapUE used the SS / PBCH block to acquire SIB1, and includes the SS / PBCH block, and does not include a CORESET with index 0 if the initial DL-BWP does not include the SS / PBCH block used by the RedCapUE to acquire SIB1.
[0040] For an active DL-BWP provided by "BWP-DownlinkDedicated", the RedCapUE shall assume that the active DL-BWP contains SS / PBCH blocks and does not contain a CORESET with index 0, unless the RedCapUE indicates the capability to operate in DL-BWP without receiving SS / PBCH blocks.
[0041] Next, the status of study on RedCap for NR Release 18 will be described. In NR Release 18, eRedCap is being studied to further reduce the complexity of RedCapUE for NR Release 17. Hereinafter, the reduced-function terminal for NR Release 17 will be referred to as RedCapUE, and the extended reduced-function terminal for NR Release 18 will be referred to as eRedCapUE, to distinguish between the two. RedCapUE is an example of a first reduced-function terminal. eRedCapUE is an example of a second reduced-function terminal. In other words, the first reduced-function terminal is a terminal in which a first function has been reduced, and the second reduced-function terminal is a terminal in which a second function different from the first function (including cases where some of the functions overlap) has been reduced.
[0042] Issues being considered include the impact on the network, coexistence of RedCap or eRedCap UEs with non-RedCap UEs in a cell, the impact on the UE, the impact on specifications, etc. Potential solutions to reduce device complexity, which may be complementary, focus on:
[0043] A first solution being considered is a reduction of the UE bandwidth to 5 MHz in FR1, which may be specified in combination with relaxed UE processing timelines for PDSCH and / or PUSCH and / or CSI.
[0044] A second solution being considered is to reduce the UE peak data rate for FR1, which may involve limited bandwidth for PDSCH and / or PUSCH, possibly specified in combination with relaxed UE processing timelines for PDSCH and / or PUSCH and / or CSI.
[0045] It is considered necessary to pay attention to the following points for eRedCapUE: It is necessary to reuse the SSB specified in NR Release 15 and minimize changes to L1. It is also necessary to consider BWP operation with / without SSB and with / without RF retuning. It is also considered that some FR1 solutions may be applicable to FR2. Finally, it is considered that a type of reduced-function terminal for a single Release 18 will be defined to further reduce the complexity of the UE.
[0046] eRedCapUE may be defined as follows:
[0047] For example, in the random access procedure, a terminal 20 that notifies that it is an eRedCapUE in at least one of Msg1, Msg3, and MsgA may be defined as an eRedCapUE. For example, an eRedCapUE may transmit Msg1 or MsgA using resources defined or configured for the eRedCapUE, or may notify that it is an eRedCapUE in a notification field in Msg3 defined for the eRedCapUE.
[0048] For example, a terminal 20 that supports specific UE capabilities may be defined as an eRedCapUE. The specific UE capabilities may be, for example, 1) to 7) shown below.
[0049] 1) Supports up to 5 MHz bandwidth for PDSCH and PUSCH in FR1. 2) Supports relaxed UE processing time for PDSCH, PUSCH, and / or CSI. 3) Supports reduced UE peak data rates in FR1. 4) Supports one or two receive branches and the corresponding maximum number of DL-MIMO layers. 5) Supports FD (Full Duplex)-FDD or Type A HD (Half Duplex)-FDD in the FR1 FDD band. 6) Supports up to 64QAM (Quadrature amplitude modulation) or 256QAM in FR1 DL. 7) Does not support carrier aggregation or dual connectivity.
[0050] Furthermore, the terminal 20 that reports to the base station 10 that it supports the specific UE capability through a UE capability report may be defined as an eRedCapUE. Note that the existing terminal may be a terminal other than an eRedCapUE.
[0051] In addition, eRedCap terminals may support the operations shown in 1)-5) below to reduce the complexity associated with UE-BB.
[0052] 1) It may be possible to receive a DL allocation contained in a DCI that allocates unicast PDSCH resources with a bandwidth exceeding 5 MHz. 2) For a broadcast PDSCH carrying SIB1, the scheduling of SIB1 may exceed 5 MHz as in legacy operation. 3) For a broadcast PDSCH carrying Other System Information (OSI), the scheduling of OSI may exceed 5 MHz as in legacy operation. 4) For a broadcast PDSCH carrying Random Access Response (RAR), the scheduling of the RAR-PDSCH may exceed the maximum number of unicast PRBs that an eRedCap terminal can process per slot. 5) For a broadcast PDSCH carrying paging, the scheduling of the paging channel may exceed 5 MHz as in legacy operation.
[0053] As described above, for RedCapUE or eRedCapUE, the following are being considered: reduction in maximum bandwidth, reduction in the number of RX branches and DL MIMO layers, maximum modulation method, half-duplex FDD operation, relaxation of processing time, and relaxation of RRM measurements for UEs near the cell center.
[0054] In addition, NTN-related characteristics may affect RedCapUE. For example, these characteristics may include performance common to DL and UL. Furthermore, these characteristics may include NTN-specific TA adjustments such as simultaneous processing of GNSS and Uu, common TA parameters, and TA updates during UL reception. Furthermore, these characteristics may include two-step RACH.
[0055] In this embodiment, the RedCapUE may include an eRedCapUE.
[0056] A RedCapUE may not be capable of simultaneous DL and UL operation in FDD, i.e., a RedCapUE is assumed to support half-duplex FDD.
[0057] Here, the case where SIB19 reception and UL transmission collide is considered.
[0058] SIB19 includes important settings for NTN. Information necessary for establishing and maintaining a connection by NTN is included in SIB19. SIB19 is also updated over time. After connecting to a base station, a UE monitors SIB19 based on a predetermined parameter (e.g., ntn-UlSyncValidityDuration, which sets the validity period of assistance information for connecting to NTN) (see Non-Patent Document 4), but does not need to monitor it constantly. Below, a method for a RedCap UE or a normal UE to prioritize reception of SIB19 will be described.
[0059] Reception of SIB19 may be prioritized in some SIB19 opportunities, and UL transmission may be prioritized in other SIB19 opportunities. The opportunities for prioritizing reception of SIB19 may be determined based on at least one of operations 1) to 6) described below. Note that at least two of operations 1) to 6) may be applied in combination, and for example, at least one of operations 3) to 6) may be applied to a reception opportunity identified in operation 1) or operation 2).
[0060] This embodiment may be applied to SIBs other than SIB19, such as SIB1, SIB25, SIB2, and SIB6. In this embodiment, UL transmission may be replaced with SL transmission. For operations 1) to 6), different operations may be applied between SIBs, different operations may be applied between UL types, or different operations may be applied depending on the UE state (IDLE, INACTIVE, CONNECTED).
[0061] Operation 1) Prioritize reception of SIB19 at a specific opportunity before timer T430, which operates based on upper layer parameters ntn-UlSyncValidityDuration and epochTime, expires, and prioritize UL transmission at other opportunities. The specific opportunity may be defined in the specification, configured by the network, or signaled. The specific opportunity may be some or all of the opportunities within the SI window. Note that the opportunity may be a reception opportunity.
[0062] The specific opportunity may be an opportunity within the SI window before the period notified by ntn-UlSyncValidityDuration and epochTime ends. Alternatively, the specific opportunity may be an opportunity within the SI window immediately before the period notified by ntn-UlSyncValidityDuration and epochTime ends. The period notified by ntn-UlSyncValidityDuration and epochTime may be a period starting from epochTime and having a length of ntn-UlSyncValidityDuration. In this embodiment, the period may refer to a validity duration.
[0063] UL transmission may be prioritized from the time when SIB19 is successfully received until the time when T430 starts or restarts, and from the time when SIB19 is successfully received until the end of the SI window.
[0064] Note that reception of SIB19 may always be given priority.
[0065] FIG. 6 is a diagram showing an example of SIB acquisition in an embodiment of the present invention. As shown in FIG. 6, timer T430, starting from epochTime, expires at the period ntn-UlSyncValidityDuration. As shown in FIG. 6, reception of SIB19 may be prioritized at, for example, the last SIB19 reception opportunity in the SI window before timer T430 expires. Transmission may be prioritized at reception opportunities other than this reception opportunity or at reception opportunities other than this reception opportunity. Reception of SIB19 at SIB19 reception opportunities other than this reception opportunity may be skipped.
[0066] 7 is a flowchart illustrating an example of SIB acquisition according to an embodiment of the present invention. In step S101, the UE starts timer T430 based on ntn-UlSyncValidityDuration and epochTime. In step S102, the UE prioritizes reception and receives SIB19 at a specific opportunity before T430 expires. The UE prioritizes transmission at opportunities other than the specific opportunity.
[0067] Operation 2) UL transmission may be prioritized within a specific period from the time when SIB19 was last successfully received and / or from the time determined based on epochTime. When the specific period has elapsed, reception of SIB19 may be prioritized. The specific period may be defined in a specification, configured by the network, or notified.
[0068] Action 3) When UL transmission and reception of SIB19 overlap in the time domain, UL transmission may be prioritized if the priority of UL transmission is 1, higher than a threshold, or associated with a high priority. Otherwise, i.e., the priority of UL transmission is 0, lower than a threshold, or associated with a low priority, reception of SIB19 may be prioritized. The threshold may be defined in the specification, configured by the network, or signaled by the network.
[0069] Operation 4) When UL transmission and reception of SIB19 overlap in the time domain, if the type of UL transmission is A, priority may be given to UL transmission, and if the type of UL transmission is B, priority may be given to reception of SIB19.
[0070] Whether the type of UL transmission is A or B may be determined based on, for example, a channel or a signal type. The channel or the signal type may be, for example, a PUCCH, a PUSCH, message 3 and / or message A (which may mean a PUSCH transmitted in random access or initial access), a PRACH (which may include message 1), an SRS, or the like.
[0071] Whether the UL transmission type is A or B may be a configuration or notification type, such as configured TX, dynamically scheduled TX, periodic TX, semi-persistent TX, aperiodic TX, etc.
[0072] Operation 5) Whether to prioritize UL transmission or SIB19 reception may be configured or signaled by the network. The configuration or signaling may be performed for each cell, for each UE, for each channel or signal type, for each channel or signal resource configuration, or for each channel or signal resource notification.
[0073] Action 6) When the UE decides to perform acquisition or reacquisition of SIB19, reception of SIB19 may be prioritized, and at other times, UL transmission may be prioritized or performed.
[0074] The above embodiment allows RedCapUE to properly acquire SIB19 and establish and maintain a connection to the NTN.
[0075] That is, in a wireless communication system, a terminal with reduced functionality can connect to an NTN (Non-Terrestrial Network).
[0076] (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.
[0077] <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.
[0078] 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.
[0079] The setting unit 130 stores preset setting information and various setting information to be transmitted to the terminal 20. The content of the setting information is, for example, information related to communication in the NTN.
[0080] 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.
[0081] <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.
[0082] 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.
[0083] 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.
[0084] 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.
[0085] (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.
[0086] 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.
[0087] 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.
[0088] 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.
[0089] 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.
[0090] 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.
[0091] 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.
[0092] 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.
[0093] 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.
[0094] 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.
[0095] 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).
[0096] 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.
[0097] 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.
[0098] 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.
[0099] 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.
[0100] 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).
[0101] 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.
[0102] 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.
[0103] 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.
[0104] 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.
[0105] 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.
[0106] 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.
[0107] 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.
[0108] (Summary of the embodiment) As described above, according to the embodiment of the present invention, in an NTN (Non-Terrestrial Network), a terminal is provided which has a receiving unit that receives system information necessary to connect to the NTN, and a control unit that determines whether to prioritize transmission or reception, and the control unit prioritizes reception during some of the opportunities to receive the system information.
[0109] With the above configuration, the RedCapUE can properly acquire the SIB19 and establish and maintain a connection to the NTN. That is, in the wireless communication system, a terminal with reduced functionality can connect to the NTN (Non-Terrestrial Network).
[0110] The control unit may prioritize transmission during all but a portion of the system information reception opportunities. This configuration allows the RedCapUE to properly acquire SIB19 and establish and maintain a connection to the NTN.
[0111] The control unit may prioritize reception of the specific system information during a period until a timer indicating a valid period for the assistance information for connecting to the NTN expires. With this configuration, the RedCapUE can properly acquire SIB19 and establish and maintain a connection to the NTN.
[0112] The control unit may prioritize reception of the system information immediately before a timer indicating a valid period for the assistance information for connecting to the NTN expires, among the opportunities to receive the system information within the period until the timer indicating a valid period for the assistance information for connecting to the NTN expires. With this configuration, the RedCapUE can appropriately acquire SIB19 and establish and maintain a connection to the NTN.
[0113] The control unit may prioritize transmission for a specific period from the time when the system information is successfully acquired, and prioritize reception after the specific period has elapsed. With this configuration, the RedCapUE can properly acquire SIB19 and establish and maintain a connection to the NTN.
[0114] Furthermore, according to an embodiment of the present invention, a communication method is provided in which a terminal executes the following steps in an NTN (Non-Terrestrial Network): receiving system information required for connecting to the NTN; determining whether to prioritize transmission or reception; and prioritizing reception during some of the opportunities to receive the system information.
[0115] With the above configuration, the RedCapUE can properly acquire the SIB19 and establish and maintain a connection to the NTN. That is, in the wireless communication system, a terminal with reduced functionality can connect to the NTN (Non-Terrestrial Network).
[0116] (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.
[0117] 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.
[0118] 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.
[0119] 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.
[0120] In this specification, a specific operation that is described as being performed by the base station 10 may also 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).
[0121] 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.
[0122] 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.
[0123] 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).
[0124] 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.
[0125] 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.
[0126] 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.
[0127] 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.
[0128] As used in this disclosure, the terms "system" and "network" are used interchangeably.
[0129] 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.
[0130] 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.
[0131] 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.
[0132] 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.
[0133] 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.
[0134] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," and the like may be used interchangeably.
[0135] 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.
[0136] 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.
[0137] 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.
[0138] 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.
[0139] 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.
[0140] 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.
[0141] The reference signal may be abbreviated as RS (Reference Signal) or may be called a pilot depending on the applicable standard.
[0142] 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."
[0143] 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.
[0144] The "means" in the configuration of each of the above devices may be replaced with "part," "circuit," "device," etc.
[0145] 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.
[0146] 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.
[0147] 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.
[0148] 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.
[0149] 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.
[0150] 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.
[0151] 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.
[0152] 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.
[0153] 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.
[0154] 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.
[0155] 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.
[0156] 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.
[0157] 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.
[0158] 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.
[0159] 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.
[0160] 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.
[0161] 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.
[0162] 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.
[0163] 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."
[0164] 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.
[0165] 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.
[0166] 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."
[0167] 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).
[0168] 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.
[0169] 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. A terminal in an NTN (Non-Terrestrial Network) that has a receiving unit that receives system information necessary to connect to the NTN, and a control unit that determines whether to prioritize transmission or reception, and the control unit prioritizes reception during some of the opportunities to receive the system information.
2. The terminal according to claim 1, wherein the control unit prioritizes transmission of the system information except for some of the opportunities to receive the system information.
3. The terminal according to claim 1, wherein the control unit prioritizes reception of the specific system information at an opportunity within a period until a timer indicating a period during which the assistance information for connecting to the NTN is valid expires.
4. The terminal according to claim 1, wherein the control unit prioritizes reception of the system information immediately before the expiration of a timer indicating the period during which assistance information for connecting to the NTN is valid, among the opportunities to receive the system information within the period until the expiration of the timer.
5. The terminal according to claim 1, wherein the control unit prioritizes transmission for a specific period from the time when the system information is successfully acquired, and prioritizes reception after the specific period has elapsed.
6. A communication method in which a terminal executes the following procedures in an NTN (Non-Terrestrial Network): receiving system information required to connect to the NTN; determining whether to prioritize transmission or reception; and prioritizing reception during some of the opportunities to receive the system information.