Terminal and communication method

Abstract

The terminal has: a receiving unit that receives system information; and a control unit that responds to a situation where it is detected that the channel bandwidth included in the system information received by the receiving unit is not supported, and during the period from when the receiving unit receives the system information until the setting information of the supported receiving channel bandwidth is received, sets the default channel bandwidth as the frequency bandwidth used for communication.

Description

Technical Field

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

[0002] In the 3rd Generation Partnership Project, in order to achieve a larger system capacity, a higher data transmission speed, a lower latency in a wireless section, etc., research on a wireless communication method called NR (New Radio) or 5G is being promoted. In NR, in order to meet the requirement conditions of achieving a throughput of 10 Gbps or more and setting the latency in the wireless section to 1 ms or less, various wireless technologies are being studied.

[0003] Currently, in meetings of 3GPP, discussions are being held on how a terminal (user equipment) uses the bandwidth of a channel broadcast in SIB1.

[0004] Prior Art Documents

[0005] Non-Patent Documents

[0006] Non-Patent Document 1: 3GPP TSG-RAN WG2 Meeting#106, R2-1908301, Reno, USA, 13-17 May 2019

[0007] Non-Patent Document 2: 3GPP TS38.101-1 V15.5.0 (2019-03)

[0008] Non-Patent Document 3: 3GPP TS38.331 V15.5.1 (2019-04) Summary of the Invention

[0009] Problems to be Solved by the Invention

[0010] When a terminal does not support the carrier bandwidth notified in SIB1, it is necessary to clearly define the frequency bandwidth used by the terminal for communication during the period until the channel bandwidth supported by the terminal is set.

[0011] Means for Solving the Problems

[0012] According to one aspect of the present invention, there is provided a terminal having: a receiving unit that receives system information; and a control unit that responds to a case where it is detected that the terminal does not support the channel bandwidth included in the system information received by the receiving unit, and sets a default channel bandwidth as the frequency bandwidth used for communication during the period from when the receiving unit receives the system information until the setting information of the channel bandwidth supported by the terminal is received.

[0013] Effect of the Invention

[0014] According to the embodiment, the following method is provided. That is, in the case where the terminal does not support the carrier bandwidth notified in SIB1, during the period until the actually supported channel bandwidth is set, the frequency bandwidth used by the terminal for communication is clearly defined. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural diagram of the communication system in this embodiment.

[0016] Figure 2 It is a diagram showing an example of a Master Information Block.

[0017] Figure 3 It is a diagram showing an example of information that can be set for the terminal through controlResourceSetZero.

[0018] Figure 4 It is a diagram showing a modified example of the specification of the SCS-SpecificCarrier information element.

[0019] Figure 5 It is a diagram showing an example of the functional structure of the terminal.

[0020] Figure 6 It is a diagram showing an example of the functional structure of the base station.

[0021] Figure 7 It is a diagram showing an example of the hardware structure of the terminal and the base station. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the embodiments described below are merely examples, and the embodiments applying the present invention are not limited to the following embodiments.

[0023] In addition, in the embodiments described below, terms such as SS (Synchronization signal), PSS (Primary SS), SSS (Secondary SS), PBCH (Physical broadcast channel), and PRACH (Physical random access channel) used in existing LTE are adopted. This is for convenience of description, and the same signals, functions, etc. may also be referred to by other names. In addition, the above terms in NR correspond to NR-SS, NR-PSS, NR-SSS, NR-PBCH, NR-PRACH, etc. However, even for the signals used in NR, they are not necessarily clearly marked as "NR-".

[0024] In addition, in the embodiments of the present invention, the duplex mode may be a TDD (Time Division Duplex) mode, an FDD (Frequency Division Duplex) mode, or may also be other modes (such as Flexible Duplex, etc.).

[0025] In addition, in the embodiments of the present invention, "being configured" for radio parameters, etc. may mean that specific values are pre-configured, or may also mean that radio parameters notified from the base station 10 or the terminal 20 are configured.

[0026] Figure 1 It is a diagram for explaining the wireless communication system in the embodiments of the present invention. As Figure 1 shown, the wireless communication system in the embodiments of the present invention includes a base station 10 and a terminal 20. In Figure 1 the figure, one base station 10 and one terminal 20 are shown respectively, but this is only an example, and there may be multiple of each.

[0027] The base station 10 is a communication device that provides more than one cell and performs wireless communication with the terminal 20. The physical resources of the wireless signal are defined in the time domain and the frequency domain. The time domain can be defined by the number of OFDM symbols, and the frequency domain can be defined by the number of subcarriers or resource blocks. The base station 10 transmits the synchronization signal and the system information to the terminal 20. The synchronization signal is, for example, NR-PSS and NR-SSS. A part of the system information is transmitted through NR-PBCH, which is also called broadcast information. The synchronization signal and the broadcast information can also be periodically transmitted as an SS block (SS / PBCH block) composed of a specific number of OFDM symbols. For example, the base station 10 transmits the control signal or data to the terminal 20 in the DL (Downlink), and receives the control signal or data from the terminal 20 in the UL (Uplink). Both the base station 10 and the terminal 20 can perform beamforming to transmit and receive signals. For example, as Figure 1 shown, the reference signal transmitted from the base station 10 includes CSI-RS (Channel State Information Reference Signal), and the channels transmitted from the base station 10 include PDCCH (Physical Downlink Control Channel) and PDSCH (Physical Downlink Shared Channel).

[0028] The terminal 20 is a communication device with a wireless communication function, such as a smart phone, a mobile phone, a tablet computer, a wearable terminal, and a communication module for M2M (Machine-to-Machine). The terminal 20 can also be called the user equipment (UE) 20. The terminal 20 receives the control signal or data from the base station 10 through the DL, and transmits the control signal or data to the base station 10 through the UL, so as to utilize various communication services provided by the wireless communication system. For example, as Figure 1 shown, in the channels transmitted from the terminal 20, there are PUCCH (Physical Uplink Control Channel) and PUSCH (Physical Uplink Shared Channel).

[0029] (PDCCH-ConfigSIB1 in NR of release 15 (version 15))

[0030] PDCCH-ConfigSIB1 in NR of release15 is an information element (IE) included in the Master Information Block (MIB).

[0031] As Figure 2 shown, in PDCCH-ConfigSIB1, there are two IEs, namely controlResourceSetZero and searchSpaceZero. controlResourceSetZero and searchSpaceZero are 4-bit parameters respectively used to notify an integer value included in the range from 0 to 15.

[0032] During cell search, if the terminal 20 determines, based on the MIB, that there is a control resource set (CORESET) of the Type0-PDCCH Common Search Space (CSS) (Type0-PDCCH Common Search Space (CSS)), it derives the number of resource blocks and the number of symbols of this CORESET from the 4 most significant bits (MSB) of PDCCH-ConfigSIB1. Here, the 4 MSB of PDCCH-ConfigSIB1 correspond to controlResourceSetZero. Further, the terminal 20 derives the PDCCH monitoring occasions from the 4 least significant bits (LSB) of PDCCH-ConfigSIB1. Here, the 4 LSB of PDCCH-ConfigSIB1 correspond to searchSpaceZero.

[0033] (controlResourceSetZero, CORESET#0)

[0034] Figure 3 is a figure (Non-Patent Document 3) showing an example of the content of the information that can be set for the terminal 20 by controlResourceSetZero. For example, when applying a subcarrier spacing of 30 kHz and the minimum channel bandwidth is 40 MHz, the terminal 20 interprets the 4 bits of controlResourceSetZero according to the Figure 3 table shown. The value of the 4 bits corresponds to the Figure 3corresponds to the index of the table, and the index takes any integer value in the range from 0 to 15. The terminal 20 sets the multiplexing pattern of the SS / PBCH block (which may also be referred to as the SS / PBCH block, SS block, or SSB) and the control resource set (Control-resource set (CORESET)), the number of resource blocks (RBs) of the CORESET, the number of symbols of the CORESET, and the resource block level offset between the SS / PBCH block and the CORESET according to the notified index value as shown in the table of Figure 3 .

[0035] Currently, in the 3GPP meeting, discussions are being held on how the terminal 20 (user equipment) uses the channel bandwidth notified in the System Information Block 1 (SIB1).

[0036] In the case where the terminal 20 does not support the channel bandwidth notified in the SIB1, in the current mechanism, it is assumed that after the establishment of the RRC connection between the terminal 20 and the base station 10, the base station 10 detects the UE capability (UE Capability) sent from the terminal 20, and according to this UE capability, signals the channel bandwidth actually supported by the terminal 20 to the terminal 20 individually via the RRC reconfiguration message (Radio Resource Control (RRC) Reconfiguration message).

[0037] However, it is not clear how to set the channel bandwidth used for the uplink signal transmission from the terminal 20 during the establishment of the RRC connection between the terminal 20 and the base station 10, the downlink signal reception in the terminal 20, and the channel bandwidth used when the terminal 20 sends the UE capability before the base station 10 detects the UE capability of the terminal 20 and sends the RRC reconfiguration message.

[0038] In SIB1, there is an information element such as SCS-SpecificCarrier. SCS-SpecificCarrier becomes a parameter for determining the carrier information for a specific numerology (subcarrier spacing (SCS)) for the initial bandwidth part. In SCS-SpecificCarrier, there is an information element such as carrierBandwidth. This information element of carrierBandwidth specifies the channel bandwidth commonly used by the terminal 20.

[0039] Here, when the terminal 20 does not support the carrier bandwidth notified in SIB1, after the carrier bandwidth is notified in this SIB1, until the base station 10 sets the channel bandwidth actually supported by the terminal 20 for the terminal 20 with dedicated signaling according to the UE capabilities received from the terminal 20, in order to clearly define the uplink bandwidth and the downlink bandwidth used by the terminal 20 for communication, it is proposed to change the carrierBandwidth information element to, for example, Figure 4 the content shown.

[0040] Figure 4 is a diagram showing a change example of the specification of the SCS-SpecificCarrier information element. In Figure 4 the example, the definition of the carrierBandwidth information element included in the SCS-SpecificCarrier information element is changed.

[0041] According to Figure 4Regarding the definition of the carrierBandwidth information element as shown in the example, for the frequency band within the cell and the subcarrier spacing, in the case where the terminal 20 does not support the DL channel bandwidth specified by the carrierBandwidth field in DownlinkConfigCommon / DownlinkConfigCommonSIB, the terminal 20 can also apply the DL channel bandwidth derived through condition X during the period until receiving RRCSetup / RRCResume / RRCReestablishment. Additionally, regarding the frequency band within the cell and the subcarrier spacing, in the case where the terminal 20 does not support the UL channel bandwidth specified by the carrierBandwidth field in UplinkConfigCommon / UplinkConfigCommonSIB, the terminal 20 can also apply the UL channel bandwidth derived through condition X during the period until receiving RRCSetup / RRCResume / RRCReestablishment.

[0042] As condition X, specifically, at least consider the following 12 conditions of Alt.1 to Alt.12.

[0043] (Alt.1)

[0044] In the case where the terminal 20 cannot support the carrier bandwidth notified in SIB1, the terminal 20 can also set the uplink frequency bandwidth and / or the downlink frequency bandwidth used for communication to the bandwidth (BW: Bandwidth) of CORESET#0.

[0045] (Alt.2)

[0046] In the case where the terminal 20 cannot support the carrier bandwidth notified in SIB1, the terminal 20 can also set the uplink bandwidth and / or the downlink bandwidth used for communication to the maximum channel bandwidth supported by the terminal 20. For example, the maximum channel bandwidth supported by the terminal 20 can also be specified by the specification.

[0047] (Alt.3)

[0048] In the case where the terminal 20 cannot support the carrier bandwidth notified in SIB1, the terminal 20 can also set the uplink frequency bandwidth and / or the downlink frequency bandwidth used for communication to the minimum channel bandwidth supported by the terminal 20. For example, the minimum channel bandwidth supported by the terminal 20 can also be specified by the specification.

[0049] (Alt.4)

[0050] When the terminal 20 cannot support the carrier bandwidth notified in SIB1, it can also set the uplink frequency bandwidth and / or the downlink frequency bandwidth used by the terminal 20 for communication to the minimum of the frequency bandwidth of CORESET#0 and the minimum frequency bandwidth supported by the terminal 20 (i.e., MIN{CORESET#0BW, the minimum channel BW supported by the UE}). For example, the minimum channel frequency bandwidth supported by the terminal 20 can also be specified by the specification.

[0051] (Alt.5)

[0052] When the terminal 20 cannot support the carrier bandwidth notified in SIB1, it can also set the uplink frequency bandwidth and / or the downlink frequency bandwidth used by the terminal 20 for communication to the minimum of the frequency bandwidth of CORESET#0 and the maximum frequency bandwidth supported by the terminal 20 (i.e., MIN{CORESET#0BW, the maximum channel BW supported by the UE}). For example, the maximum channel bandwidth supported by the terminal 20 can also be specified by the specification.

[0053] (Alt.6)

[0054] When the terminal 20 cannot support the carrier bandwidth notified in SIB1, it can also set the uplink frequency bandwidth and / or the downlink frequency bandwidth used by the terminal 20 for communication to the maximum of the frequency bandwidth of CORESET#0 and the maximum frequency bandwidth supported by the terminal 20 (i.e., MAX{CORESET#0BW, the maximum channel BW supported by the UE}). For example, the maximum channel bandwidth supported by the terminal 20 can also be specified by the specification.

[0055] (Alt.7)

[0056] When the terminal 20 cannot support the carrier bandwidth notified in SIB1, it can also set the uplink frequency bandwidth and / or the downlink frequency bandwidth used by the terminal 20 for communication to the maximum of the frequency bandwidth of CORESET#0 and the minimum frequency bandwidth supported by the terminal 20 (i.e., MAX{CORESET#0BW, the maximum channel BW supported by the UE}). For example, the maximum channel bandwidth supported by the terminal 20 can also be specified by the specification.

[0057] (Alt.8)

[0058] In the case where the terminal 20 cannot support the carrier bandwidth notified in SIB1, for each frequency band, the frequency bandwidth envisaged by the terminal 20 can also be uniquely specified in the specification.

[0059] (Alt.9)

[0060] In the case where the terminal 20 cannot support the carrier bandwidth notified in SIB1, the frequency bandwidth of the uplink and / or downlink used by the terminal 20 for communication can also be set to the minimum of the frequency bandwidth of CORESET#0, the maximum frequency bandwidth supported by the terminal 20, and the frequency bandwidth envisaged by the terminal 20 uniquely specified in the specification for the frequency band (i.e., MIN{CORESET#0BW, the maximum channel BW supported by the UE, the frequency bandwidth envisaged by the terminal 20 uniquely specified in the specification for the frequency band}).

[0061] (Alt.10)

[0062] In the case where the terminal 20 cannot support the carrier bandwidth notified in SIB1, the frequency bandwidth of the uplink and / or downlink used by the terminal 20 for communication can also be set to the minimum of the frequency bandwidth of CORESET#0, the minimum frequency bandwidth supported by the terminal 20, and the frequency bandwidth envisaged by the terminal 20 uniquely specified in the specification for the frequency band (i.e., MIN{CORESET#0BW, the minimum channel BW supported by the UE, the frequency bandwidth envisaged by the terminal 20 uniquely specified in the specification for the frequency band}).

[0063] (Alt.11)

[0064] In the case where the terminal 20 cannot support the carrier bandwidth notified in SIB1, the frequency bandwidth of the uplink and / or downlink used by the terminal 20 for communication can also be set to the maximum of the frequency bandwidth of CORESET#0, the maximum frequency bandwidth supported by the terminal 20, and the frequency bandwidth envisaged by the terminal 20 uniquely specified in the specification for the frequency band (i.e., MAX{CORESET#0BW, the maximum channel BW supported by the UE, the frequency bandwidth envisaged by the terminal 20 uniquely specified in the specification for the frequency band}).

[0065] (Alt.12)

[0066] In the case where the terminal 20 cannot support the carrier bandwidth notified in SIB1, the uplink frequency bandwidth and / or the downlink frequency bandwidth used by the terminal 20 for communication can also be set to the maximum of the frequency bandwidth of CORESET#0, the minimum frequency bandwidth supported by the terminal 20, and the frequency bandwidth envisioned for the terminal 20 uniquely specified in the specification for the frequency band (i.e., MAX{CORESET#0 BW, the minimum channel BW supported by the UE, the frequency bandwidth envisioned for the terminal 20 uniquely specified in the specification for the frequency band}).

[0067] According to the above Alt.1 to Alt.12, in the case where the terminal 20 cannot support the carrier bandwidth broadcast in SIB1, it is possible to clearly specify the uplink frequency bandwidth and the downlink frequency bandwidth used by the terminal 20 during the period from when the carrier bandwidth is notified in the SIB1 until the base station 10 sets the channel bandwidth actually supported by the terminal 20 for the terminal 20 with dedicated signaling based on the UE capabilities received from the terminal 20.

[0068] (Variant example)

[0069] In the case where the terminal 20 cannot support the carrier bandwidth notified in SIB1, the uplink frequency bandwidth used by the terminal 20 for communication can be set to one of the frequency bandwidths in the above Alt.1 to Alt.12, and the downlink frequency bandwidth used by the terminal 20 for communication can also be set to one of the frequency bandwidths other than the frequency bandwidth set as the uplink frequency bandwidth in the above Alt.1 to Alt.12.

[0070] For example, in the case where the terminal 20 cannot support the carrier bandwidth notified in SIB1, the uplink frequency bandwidth used by the terminal 20 for communication can be set to the minimum of the frequency bandwidth of CORESET#0 and the minimum frequency bandwidth supported by the terminal 20 (i.e., MIN{CORESET#0 BW, the minimum channel BW supported by the UE}), and the downlink frequency bandwidth used by the terminal 20 for communication can also be set to the maximum of the frequency bandwidth of CORESET#0 and the maximum frequency bandwidth supported by the terminal 20 (i.e., MAX{CORESET#0 BW, the maximum channel BW supported by the UE}).

[0071] (Device structure)

[0072] Next, an example of the functional configurations of the base station 10 and the terminal 20 that perform the processing operations described so far will be described. The base station 10 and the terminal 20 have all the functions described in the present embodiment. However, the base station 10 and the terminal 20 may also have only a part of all the functions described in the present embodiment.

[0073] <Base Station 10>

[0074] Figure 5 This is a diagram showing an example of the functional configuration of the base station 10. As Figure 5 shown, the base station 10 includes a transmission unit 110, a reception unit 120, and a control unit 130. Figure 5 The functional configuration shown is merely an example. As long as the operations according to the present embodiment can be performed, the functional division and the names of the functional units can be arbitrary.

[0075] The transmission unit 110 creates a transmission signal from the transmission data and transmits the transmission signal wirelessly. The reception unit 120 wirelessly receives various signals and obtains a higher-layer signal from the received physical-layer signal. In addition, the reception unit 120 includes a measurement unit that measures the received signal to obtain the received power and the like.

[0076] The control unit 130 controls the base station 10. In addition, the function of the control unit 130 related to transmission may be included in the transmission unit 110, and the function of the control unit 130 related to reception may be included in the reception unit 120.

[0077] In the base station 10, the control unit 130 sets controlResourceSetZero in PDCCH-ConfigSIB1, which is an information element included in the MIB, and the transmission unit 110 transmits the MIB to the terminal 20. In addition, in the base station 10, the control unit 130 sets the channel bandwidth commonly used by the terminal 20 in the carrierBandwidth information element in the SCS-SpecificCarrier information element included in SIB1, and the transmission unit 110 transmits SIB1 including the carrierBandwidth information element to the terminal 20.

[0078] In addition, in base station 10, control unit 130 sets the following in the carrierBandwidth information element within the SCS-SpecificCarrier information element included in SIB1: Regarding the frequency band and subcarrier spacing within the cell, in the case where terminal 20 does not support the DL channel bandwidth specified by the carrierBandwidth field in DownlinkConfigCommon / DownlinkConfigCommonSIB, terminal 20 applies the DL channel bandwidth derived through condition X during the period until receiving RRCSetup / RRCResume / RRCReestablishment; and regarding the frequency band and subcarrier spacing within the cell, in the case where terminal 20 does not support the UL channel bandwidth specified by the carrierBandwidth field in UplinkConfigCommon / UplinkConfigCommonSIB, terminal 20 applies the UL channel bandwidth derived through condition X during the period until receiving RRCSetup / RRCResume / RRCReestablishment. Transmission unit 110 may also transmit SIB1 containing this carrierBandwidth information element to terminal 20.

[0079] <Terminal 20>

[0080] Figure 6 is a diagram showing an example of the functional structure of terminal 20. As Figure 6 shown, terminal 20 includes a transmission unit 210, a reception unit 220, and a control unit 230. Figure 6 The functional structure shown is merely an example. As long as the operations related to this embodiment can be performed, the functional division and the names of the functional units can be arbitrary.

[0081] Transmission unit 210 includes the function of generating a signal to be transmitted to base station 10 side and wirelessly transmitting this signal. Reception unit 220 includes the function of receiving various signals transmitted from base station 10 and obtaining, for example, higher layer information from the received signals. In addition, reception unit 220 includes a measurement unit that measures the received signals to obtain measurement results such as received power.

[0082] Control unit 230 controls terminal 20. In addition, the function of control unit 230 related to transmission may also be included in transmission unit 210, and the function of control unit 230 related to reception may also be included in reception unit 220.

[0083] For example, in the terminal 20, the receiving unit 220 receives the MIB by receiving the SS / PBCH block, and the control unit 230 sets the controlResourceSetZero and searchSpaceZero according to the PDCCH-ConfigSIB1 included in the MIB.

[0084] In addition, in the terminal 20, the receiving unit 220 monitors the PDCCH according to the settings of the controlResourceSetZero and searchSpaceZero set by the control unit 230 and receives the SIB1. In addition, in the terminal 20, when the control unit 230 detects that the channel bandwidth notified in the SIB1 is not supported, during the period until receiving RRCSetup / RRCResume / RRCReestablishment, the DL channel bandwidth derived by the above condition X can be applied, and / or the UL channel bandwidth derived by the above condition X can also be applied.

[0085] <Hardware Structure>

[0086] The block diagram for explaining the above embodiment ( Figures 5 - 6 ) shows the blocks of functional units. These functional blocks (structural units) are implemented by any combination of at least one of hardware and software. In addition, the implementation method of each functional block is not particularly limited. That is, each functional block can be implemented by using one physically or logically combined device, or two or more physically or logically separated devices can be directly or indirectly (for example, using wired, wireless, etc.) connected and these multiple devices can be used to implement. The functional block can also be implemented by combining software on the above one device or the above multiple devices. Among the functions, there are judgment, decision, determination, calculation, calculation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, solution, selection, selection, establishment, comparison, assumption, expectation, regarded as, broadcasting, notifying, communicating, forwarding, configuring (configuring), reconfiguring (reconfiguring), allocating (allocating, mapping), assigning (assigning), etc., but not limited to this. For example, the functional block (structural unit) that plays the transmission function can also be called a transmitting unit or a transmitter. Each is the same as above, and the implementation method is not particularly limited.

[0087] In addition, for example, in one embodiment of the present invention, both the base station 10 and the terminal 20 can have the functions of a computer that performs the processing involved in this embodiment. Figure 7 A diagram showing an example of the hardware structure of the base station 10 and the terminal 20 involved in this embodiment. The above base station 10 and terminal 20 can also be physically configured as computer devices 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 addition, in the following description, the term "device" can be replaced with a circuit, equipment, unit, etc. The hardware structure of the base station 10 and the terminal 20 can be configured to include one or more of the devices represented by 1001 to 1006 shown in the figure, or can be configured not to include some of the devices.

[0089] Each function in the base station 10 and the terminal 20 is realized by reading a specific software (program) into hardware such as the processor 1001 and the storage device 1002, so that the processor 1001 performs operations, controls communication based on the communication device 1004, or controls either the reading or writing of data in the storage device 1002 and the auxiliary storage device 1003.

[0090] The processor 1001, for example, operates an operating system to control the entire computer. The processor 1001 can also be composed of a central processing unit (CPU: Central Processing Unit) including an interface with peripheral devices, a control device, an arithmetic device, registers, etc.

[0091] In addition, the processor 1001 reads a program (program code), a software module, 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 according to these. As the program, a program that causes the computer to execute at least a part of the operations described in the above embodiment can be used. For example, the control unit 130 of the base station 10 can be realized by a control program stored in the storage device 1002 and operating in the processor 1001, and the same can be applied to other functional blocks. The gist that the above various processes are executed by one processor 1001 can also be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 can be installed in one or more chips. In addition, the program can also be sent from a network via a telecommunications line.

[0092] The storage device 1002 can also be a computer-readable recording medium, for example, composed of at least one of ROM (Read Only Memory), EPROM (Erasable Programmable ROM), EEPROM (Electrically Erasable Programmable ROM), RAM (Random Access Memory), etc. The storage device 1002 can also be referred to as a register, cache, main memory (main storage device), etc. The storage device 1002 can store programs (program codes), software modules, etc. that can be executed to implement the communication method according to an embodiment of the present disclosure.

[0093] The auxiliary storage device 1003 can also be a computer-readable recording medium, for example, composed of at least one of optical discs such as CD-ROM (Compact Disc ROM), hard disk drives, flexible discs, magneto-optical discs (e.g., compact discs, digital versatile discs, Blu-ray (registered trademark) discs), smart cards, flash memories (e.g., cards, sticks, key drives), Floppy (registered trademark) discs, magnetic stripes, etc. The above storage media can also be, for example, a database, a server, or other suitable media that includes at least one of the storage device 1002 and the auxiliary storage device 1003.

[0094] The communication device 1004 is hardware (transmitting and receiving device) for performing communication between computers via at least one of a wired network and a wireless network, and is also referred to as a network device, network controller, network card, communication module, etc., for example. The communication device 1004 can be configured to include, for example, a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. to implement at least one of frequency division duplex (FDD: Frequency Division Duplex) and time division duplex (TDD: Time Division Duplex).

[0095] The input device 1005 is an input device that accepts input from the outside (e.g., keyboard, mouse, microphone, switch, button, sensor, etc.). The output device 1006 is an output device that performs output to the outside (e.g., display, speaker, LED light, etc.). In addition, the input device 1005 and the output device 1006 can also be of an integrated structure (e.g., a touch panel).

[0096] In addition, devices such as the processor 1001 and the storage device 1002 are connected via a bus 1007 for communicating information. The bus 1007 can be configured with a single bus or with different buses between each device.

[0097] In addition, the base station 10 and the terminal 20 can each be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), and an FPGA (Field Programmable Gate Array), and a part or all of each functional block can also be implemented by this hardware. For example, the processor 1001 can also be installed using at least one of these hardware components.

[0098] (Summary of the Embodiment)

[0099] In this specification, at least the following terminal and communication method are disclosed.

[0100] A terminal includes: a receiving unit that receives system information; and a control unit that responds to a situation where it is detected that the channel bandwidth included in the system information received by the receiving unit is not supported, and during the period from when the receiving unit receives the system information until the setting information of the supported channel bandwidth is received, sets the default channel bandwidth setting as the frequency bandwidth for communication.

[0101] According to the above structure, when the terminal does not support the carrier bandwidth notified in SIB1, it is possible to clearly define the frequency bandwidth used by the terminal for communication during the period from when the carrier bandwidth is notified in SIB1 until the base station sets the channel bandwidth actually supported by the terminal for the terminal with dedicated signaling based on the UE capability received from the terminal.

[0102] During the period from when the receiving unit receives the system information until the setting information of the supported channel bandwidth is received, the control unit applies the same default channel bandwidth as the frequency bandwidth for uplink communication and the frequency bandwidth for downlink communication.

[0103] According to the above structure, since the same default channel bandwidth is applied as the frequency bandwidth for uplink communication and the frequency bandwidth for downlink communication, the implementation of the terminal becomes easy.

[0104] The default channel bandwidth may be one of the following bandwidths: the frequency bandwidth set by controlResourceSetZero (CORESET#0) included in the Master Information Block (MIB); the maximum channel bandwidth supported by the terminal; the minimum channel bandwidth supported by the terminal; the minimum of the frequency bandwidth set by the CORESET#0 and the minimum frequency bandwidth supported by the terminal; the minimum of the frequency bandwidth set by the CORESET#0 and the maximum frequency bandwidth supported by the terminal; the maximum of the frequency bandwidth set by the CORESET#0 and the maximum frequency bandwidth supported by the terminal; the maximum of the frequency bandwidth set by the CORESET#0 and the minimum frequency bandwidth supported by the terminal.

[0105] According to the above structure, the default channel bandwidth can be set according to the frequency bandwidth of the assumed supported situation of the terminal.

[0106] The default channel bandwidth may also be the frequency bandwidth uniquely specified in the specification for each frequency band.

[0107] According to the above structure, since the default channel bandwidth is uniquely specified in the specification for each frequency band, in the case where the terminal does not support the carrier bandwidth notified in SIB1, it is possible to more clearly specify the frequency bandwidth used by the terminal for communication during the period from when the carrier bandwidth is notified in the SIB1 until the base station sets the channel bandwidth actually supported by the terminal for the terminal with dedicated signaling based on the UE capability received from the terminal.

[0108] The control unit may also apply different default channel bandwidths to the frequency bandwidth for uplink communication and the frequency bandwidth for downlink communication, respectively, during the period from when the receiving unit receives the system information until the setting information of the supported channel bandwidth is received.

[0109] According to the above structure, different bandwidths can be set for uplink and downlink as the default channel bandwidth.

[0110] A terminal-based communication method includes: a step of receiving system information; and a step of answering to the detected situation of not supporting the channel bandwidth included in the received system information, and setting a default channel bandwidth as the frequency bandwidth for communication during the period from when the system information is received until the setting information of the supported channel bandwidth is received.

[0111] According to the above structure, in the case where the terminal does not support the carrier bandwidth notified in SIB1, it is possible to clearly define the frequency bandwidth used by the terminal for communication during the period from when the carrier bandwidth is notified in the SIB1 until the base station sets the channel bandwidth actually supported by the terminal for the terminal with dedicated signaling according to the UE capability received from the terminal.

[0112] (Supplement of the Embodiment)

[0113] The embodiments of the present invention have been described above. However, the disclosed invention is not limited to such embodiments, and those skilled in the art will understand various variations, modifications, substitution examples, replacement examples, etc. For the purpose of facilitating the understanding of the invention, specific numerical examples have been used for illustration. However, unless otherwise specified, these numerical values are merely examples, and any appropriate values can also be used. The classification of items in the above description is not essential in the present invention, and the matters described in two or more items can be combined and used as needed, and the matters described in one item can be applied to the matters described in other items (as long as there is no contradiction). The boundaries of functional units or processing units in the functional block diagram do not necessarily correspond to the boundaries of physical components. The operations of multiple functional units can also be physically performed by one component, or the operation of one functional unit can also be physically performed by multiple components. Regarding the processing procedures described in the embodiments, the order of processing can also be swapped as long as there is no contradiction. For the convenience of processing description, the base station 10 and the terminal 20 are illustrated using functional block diagrams. However, such devices can also be implemented by hardware, by software, or by a combination thereof. The software operating according to the embodiments of the present invention by the processor of the base station 10 and the software operating according to the embodiments of the present invention by the processor of the terminal 20 can also be stored in a random access memory (RAM), a flash memory, a read-only memory (ROM), an EPROM, an EEPROM, a register, a hard disk drive (HDD), a removable disk, a CD-ROM, a database, a server, or any other suitable storage medium.

[0114] In addition, the notification of information is not limited to the methods / embodiments described in the present disclosure, and other methods can also be used. For example, the notification of information can also be implemented through physical layer signaling (e.g., DCI (Downlink Control Information), UCI (Uplink Control Information)), high layer signaling (e.g., RRC (Radio Resource Control) signaling, MAC (Medium Access Control) signaling, broadcast information (MIB (Master Information Block), SIB (System Information Block))), other signals, or a combination thereof. In addition, the RRC signaling can also be referred to as an RRC message. For example, it can also be an RRC Connection Setup message, an RRC Connection Reconfiguration message, etc.

[0115] Each method / embodiment described in the present disclosure can also be applied to at least one of LTE (Long Term Evolution), LTE-A (LTE-Advanced), 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-WideBand), Bluetooth (registered trademark), a system using other appropriate systems, and a next-generation system extended based on them. In addition, multiple systems can also be combined (e.g., a combination of at least one of LTE and LTE-A and 5G, etc.) and applied.

[0116] The processing procedures, timings, flows, etc. of each mode / embodiment described in this specification can be changed in order as long as there is no contradiction. For example, regarding the methods described in this disclosure, the elements of various steps are presented in an illustrative order and are not limited to the specific order presented.

[0117] Specific operations assumed to be performed by the base station 10 in this disclosure may sometimes be performed by its upper node according to circumstances. Obviously, in a network composed of one or more network nodes having the base station 10, various operations for communication with the terminal 20 can be performed by at least one of the base station 10 and other network nodes other than the base station 10 (for example, MME or S-GW etc. can be considered, but not limited thereto). In the above, the case where there is one other network node other than the base station 10 is illustrated, however, the other network nodes can also be a combination of multiple other network nodes (for example, MME and S-GW).

[0118] Information etc. can also be output from a higher layer (or a lower layer) to a lower layer (or a higher layer). It can also be input and output via multiple network nodes.

[0119] The information etc. that is input and output can also be saved to a specific part (for example, a memory), and can also be managed using a management table. The information etc. that is input and output can be overwritten, updated or appended. The information etc. that is output can also be deleted. The information etc. that is input can also be sent to other devices.

[0120] The determination can also be made by a value represented by 1 bit (0 or 1), can also be made by a true / false value (boolean: true or false), and can also be made by a numerical comparison (for example, comparison with a specific value).

[0121] Each mode / embodiment described in this disclosure can be used alone, can be used in combination, or can be switched and used along with execution. In addition, the notification of specific information (for example, the notification of "is X") is not limited to being explicitly performed, and can also be performed implicitly (for example, by not notifying the specified information).

[0122] Regardless of whether software is called software, firmware, middleware, microcode, hardware description language, or is called by other names, it should be broadly interpreted as meaning instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, execution threads, processes, functions, etc.

[0123] In addition, software, instructions, information, etc. can also be sent and received via a transmission medium. For example, when software is sent from a website, server, or other remote source using at least one of wired technologies (such as coaxial cables, fiber optic cables, twisted pairs, digital subscriber line (DSL), etc.) and wireless technologies (such as infrared rays, microwaves, etc.), at least one of these wired technologies and wireless technologies is included in the definition of the transmission medium.

[0124] The information, signals, etc. described in this disclosure can also be represented using one of various different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that can be mentioned throughout the above description can also be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0125] In addition, for the terms described in this disclosure and the terms required for the understanding of this disclosure, they can also be replaced with terms having the same or similar meanings. For example, at least one of a channel and a symbol can also be a signal (signaling). In addition, a signal can also be a message. In addition, a component carrier (CC) can also be referred to as a carrier frequency, a cell, a frequency carrier, etc.

[0126] Terms such as "system" and "network" used in this disclosure can be used interchangeably. In addition, the information, parameters, etc. described in this disclosure can be represented using absolute values, can also be represented using relative values from a specific value, and can also be represented using corresponding other information. For example, a radio resource can also be indicated by an index.

[0127] The names used for the above parameters are not restrictive names at any point. Further, there are also cases where mathematical formulas, etc. using these parameters are different from the mathematical formulas explicitly disclosed in this disclosure. Various channels (such as PUCCH, PDCCH, etc.) and information elements can be identified by all suitable names, so the various names assigned to these various channels and information elements are not restrictive names at any point.

[0128] 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", "component carrier" can be used interchangeably. A base station is sometimes referred to by terms such as macro cell, small cell, femto cell, pico cell, etc.

[0129] A base station can accommodate one or more (e.g., three) cells. In the case where a base station accommodates multiple cells, the overall coverage area of the base station can be divided into multiple smaller areas, and each of the smaller areas can also provide communication services through a base station subsystem (e.g., a small indoor base station (Remote Radio Head (RRH))). Terms such as "cell" or "sector" refer to a part or the whole of the coverage area of at least one of the base station and the base station subsystem that provides communication services within that coverage range.

[0130] In the present disclosure, terms such as "Mobile Station (MS)", "user terminal", "user device (User Equipment (UE))", and "terminal" can be used interchangeably.

[0131] A mobile station is sometimes referred to by those skilled in the art as a subscriber station, mobile unit, subscriber unit, radio unit, remote unit, mobile device, radio device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, hand set, user agent, mobile client, client, or several other appropriate terms.

[0132] At least one of the base station and the mobile station may also be referred to as a transmitting device, a receiving device, a communication device, etc. Additionally, at least one of the base station and the mobile station may also be a device mounted on a moving body, the moving body itself, etc. The moving body may be a vehicle (e.g., a car, an airplane, etc.), a moving body that moves in an unmanned manner (e.g., a drone, a self-driving car, etc.), or a robot (humanoid or non-humanoid). Further, at least one of the base station and the mobile station also includes a device that does not necessarily move during a communication operation. For example, at least one of the base station and the mobile station may also be an IoT (Internet of Things) device such as a sensor.

[0133] In addition, the base station in the present disclosure may also be replaced by a user terminal. For example, for a structure in which communication between the base station and the user terminal is replaced by communication between multiple user terminals (e.g., may also be referred to as Device-to-Device, V2X (Vehicle-to-Everything), etc.), each mode / embodiment of the present disclosure can also be applied. In this case, the user terminal 20 has a structure with the functions of the terminal 20 described above. Further, terms such as "uplink" and "downlink" can also be replaced by terms corresponding to inter-terminal communication (e.g., "side"). For example, an uplink channel, a downlink channel, etc. can also be replaced by a side channel. Similarly, the user terminal in the present disclosure can also be replaced by a base station. In this case, it can be set that the terminal 20 has a structure with the functions of the user terminal 20 described above.

[0134] Terms such as "connected" and "coupled", or all their variations, mean any direct or indirect connection or coupling between two or more elements, and can include one or more intermediate elements existing between the two elements that are "connected" or "coupled" to each other. The coupling or connection between elements can be physical, logical, or a combination of them. For example, "connected" can also be replaced by "accessed". When used in the disclosure, it can be considered that two elements are "connected" or "coupled" to each other using at least one of one or more electric wires, cables, and printed electrical connections, and as several non-limiting and non-exhaustive examples, using electromagnetic energy having wavelengths in the radio frequency domain, microwave region, and optical (both visible and invisible light) region, etc.

[0135] The reference signal can also be abbreviated as RS (Reference Signal), and depending on the applied standard, it can also be referred to as a Pilot, etc.

[0136] In the present disclosure, the description such as "based on" does not mean "only based on" unless otherwise specified. In other words, the description such as "based on" means both "only based on" and "at least based on".

[0137] Any reference to elements using designations such as "first", "second", etc. used in the present disclosure does not globally define the quantity or order of these elements. These designations can be used in the present disclosure as a convenient method for distinguishing between two or more elements. Thus, the reference to the first and second elements does not mean that only two elements can be adopted, or that the first element must precede the second element in some form.

[0138] In the present disclosure, when the terms "include", "including", and their variants are used, these terms, like the term "comprising", have an inclusive meaning. Further, the term "or" used in the present disclosure does not mean the exclusive or meaning.

[0139] A radio frame may also be composed of one or more frames in the time domain.

[0140] In the time domain, each frame in one or more frames may also be referred to as a subframe.

[0141] Further, a subframe may also be composed of one or more time slots in the time domain. A subframe may also be a fixed time length (e.g., 1 ms) independent of the numerology.

[0142] The numerology may also be communication parameters applied to at least one of transmission and reception of a certain signal or channel. The numerology may, for example, also represent at least one of subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, radio frame structure, specific filtering processing performed by a transmitter-receiver in the frequency domain, specific windowing processing performed by a transmitter-receiver in the time domain, etc.

[0143] A time slot may also be composed of one or more symbols (OFDM (Orthogonal Frequency Division Multiplexing) symbols, SC-FDMA (Single Carrier Frequency Division Multiple Access) symbols, etc.) in the time domain. A time slot may also be a time unit based on the numerology.

[0144] A time slot may also include multiple mini time slots. Each mini time slot may also be composed of one or more symbols in the time domain. In addition, a mini time slot may also be referred to as a sub time slot. A mini time slot may also be composed of fewer symbols than the number of symbols in a time slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a mini time slot may also be referred to as PDSCH (or PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a mini time slot may also be referred to as PDSCH (or PUSCH) mapping type B.

[0145] A radio frame, a subframe, a time slot, a mini time slot, and a symbol all represent time units for signal transmission. A radio frame, a subframe, a time slot, a mini time slot, and a symbol may also use other names corresponding to them respectively.

[0146] For example, 1 subframe may also be referred to as a transmission time interval (TTI: Transmission Time Interval), multiple consecutive subframes may also be referred to as a TTI, 1 time slot or 1 mini time slot may also be referred to as a TTI. That is, at least one of a subframe and a TTI may be a subframe (1 ms) in the existing LTE, may be a period shorter than 1 ms (for example, 1 - 13 symbols), or may be a period longer than 1 ms. In addition, the unit representing a TTI may also be referred to as a time slot, a mini time slot, etc., rather than a subframe.

[0147] Here, a TTI refers to, for example, the minimum time unit for scheduling in wireless communication. For example, in an LTE system, a base station performs scheduling to allocate radio resources (such as the frequency bandwidth and transmission power that can be used in each user terminal) to each user terminal in units of TTI. In addition, the definition of a TTI is not limited to this.

[0148] A TTI may also be a transmission time unit for a data packet (transmission block), a code block, a codeword, etc. after channel coding, and may also become a processing unit for scheduling, link adaptation, etc. In addition, when a TTI is given, the actual time interval (for example, the number of symbols) in which a transmission block, a code block, a codeword, etc. are mapped may be shorter than the TTI.

[0149] In addition, when 1 time slot or 1 mini time slot is referred to as a TTI, 1 or more TTIs (that is, 1 or more time slots or 1 or more mini time slots) may also become the minimum time unit for scheduling. In addition, the number of time slots (mini time slots) constituting the minimum time unit of this scheduling may also be controlled.

[0150] A TTI with a time length of 1 ms can also be referred to as a normal TTI (the TTI in LTE Rel. 8-12), a normal TTI, a long TTI, a normal subframe, a long subframe, a time slot, etc. A TTI shorter than the normal TTI can also be referred to as a shortened TTI, a short TTI, a partial TTI (partial or fractional TTI), a shortened subframe, a short subframe, a mini-slot, a sub-slot, a time slot, etc.

[0151] In addition, a long TTI (e.g., a normal TTI, a subframe, etc.) can also be replaced with a TTI having a time length exceeding 1 ms, and a short TTI (e.g., a shortened TTI, etc.) can also be replaced with a TTI having a TTI length less than that of the long TTI and greater than or equal to 1 ms.

[0152] A resource block (RB) is a resource allocation unit in the time domain and the frequency domain, and can also include one or more consecutive subcarriers (subcarriers) in the frequency domain. The number of subcarriers included in an RB can be the same regardless of the parameter set, for example, it can also be 12. The number of subcarriers included in an RB can also be determined based on the parameter set.

[0153] In addition, in the time domain, an RB can include one or more symbols, and can also be the length of 1 time slot, 1 mini-slot, 1 subframe, or 1 TTI. 1 TTI, 1 subframe, etc. can also be composed of one or more resource blocks respectively.

[0154] In addition, one or more RBs can also be referred to as a physical resource block (PRB: Physical RB), a sub-carrier group (SCG: Sub-Carrier Group), a resource element group (REG: Resource Element Group), a PRB pair, an RB pair, etc.

[0155] In addition, a resource block can also be composed of one or more resource elements (RE: Resource Element). For example, 1 RE can also be a radio resource area of 1 subcarrier and 1 symbol.

[0156] A bandwidth part (BWP: Bandwidth Part) (which can also be referred to as a partial bandwidth, etc.) can also represent a subset of consecutive common RBs (common resource blocks) for a certain parameter set in a certain carrier. Here, the common RB can also be determined by the index of the RB based on the common reference point of the carrier. The PRB is defined in a certain BWP and can also be numbered within that BWP.

[0157] In a BWP, a BWP for UL (UL BWP) and a BWP for DL (DL BWP) can also be included. For a UE, one or more BWPs can also be configured within one carrier.

[0158] At least one of the configured BWPs can be active, and the UE may not assume that it transmits and receives specific signals / channels in BWPs other than the active BWP. In addition, in the present disclosure, terms such as "cell" and "carrier" can also be replaced with "BWP".

[0159] The structures of the above-mentioned radio frames, subframes, time slots, mini-slots, and symbols are merely examples. For example, the number of subframes included in a radio frame, the number of time slots per subframe or radio frame, the number of mini-slots included in a time slot, the number of symbols and RBs included in a time slot or mini-slot, the number of subcarriers included in an RB, and the number of symbols, symbol length, cyclic prefix (CP) length, etc. within a TTI can be variously changed.

[0160] In the present disclosure, when articles such as "a", "an", and "the" in English are added through translation, cases where the nouns following these articles are in the plural form can also be included in the present disclosure.

[0161] In the present disclosure, a term such as "A and B are different" can also mean that "A and B are different from each other". In addition, this term also means that "A and B are each different from C". Terms such as "separate" and "combine" can also be interpreted in the same way as "different".

[0162] As described above, the present invention has been described in detail. However, for those skilled in the art, the present invention is obviously not limited to the embodiments described in this specification. The present invention can be implemented in the form of modifications and changes without departing from the gist and scope of the present disclosure determined by the claims. Therefore, the description of the present disclosure is for illustrative purposes and has no limiting meaning for the present disclosure.

[0163] Reference Signs Explanation

[0164] 10 Base Station

[0165] 110 Transmitting Unit

[0166] 120 Receiving Unit

[0167] 130 Control Unit

[0168] 20 Terminal

[0169] 210 Transmitting Unit

[0170] 220 Receiving Unit

[0171] 230 Control Unit

[0172] 1001 Processor

[0173] 1002 Storage Device

[0174] 1003 Auxiliary Storage Device

[0175] 1004 Communication Device

[0176] 1005 Input Device

[0177] 1006 Output Device

Claims

1. A terminal, comprising: A receiving unit, configured to receive system information; A control unit, when the channel bandwidth indicated by the system information received by the receiving unit is not supported, sets the bandwidth specified for an initial bandwidth portion as the frequency bandwidth for communication, The control unit applies the same bandwidth specified for the initial bandwidth portion as the frequency bandwidth for uplink communication and the frequency bandwidth for downlink communication.

2. The terminal according to claim 1, wherein, The bandwidth specified for the initial bandwidth part is a frequency bandwidth set according to the control resource set (controlResourceSetZero (CORESET#0)) indicated by the information included in the master information block (MIB).

3. The terminal according to claim 1, wherein, In the case where the RRC connection with the base station has not been established after the receiving unit receives the system information, the control unit uses the maximum of the bandwidth specified for the initial bandwidth part and the maximum supported bandwidth.

4. A communication method based on a terminal, comprising: A step of receiving system information; and A step of, when the channel bandwidth indicated by the received system information is not supported, setting the bandwidth specified for an initial bandwidth portion as the frequency bandwidth for communication, In the step of making the setting, the same bandwidth specified for the initial bandwidth portion is applied as the frequency bandwidth for uplink communication and the frequency bandwidth for downlink communication.

5. A base station, comprising: A sending unit, configured to send system information; and A receiving unit, for a terminal that does not support the channel bandwidth indicated by the system information sent by the sending unit, receives a signal using the bandwidth specified for an initial bandwidth portion as the frequency bandwidth for communication, Applies the same bandwidth specified for the initial bandwidth portion as the frequency bandwidth for uplink communication and the frequency bandwidth for downlink communication.

6. A wireless communication system comprising a base station and a terminal, The base station comprises: A sending unit, configured to send system information; and A receiving unit, configured to receive a signal, The terminal comprises: A receiving unit, configured to receive the system information; and A control unit, when the channel bandwidth indicated by the system information is not supported, sets the bandwidth specified for an initial bandwidth portion as the frequency bandwidth for communication with the base station, The control unit applies the same bandwidth specified for the initial bandwidth portion as the frequency bandwidth for uplink communication and the frequency bandwidth for downlink communication. The receiving unit of the base station sets the bandwidth specified for the initial bandwidth portion as the frequency bandwidth for communicating with the terminal, and receives a signal from the terminal.

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