WO2023199393A1

WO2023199393A1 - Terminal, base station, and communication method

Info

Publication number: WO2023199393A1
Application number: PCT/JP2022/017545
Authority: WO
Inventors: 知也小原; 拓真中村; 浩樹原田
Original assignee: 株式会社Ｎｔｔドコモ
Priority date: 2022-04-11
Filing date: 2022-04-11
Publication date: 2023-10-19

Abstract

Provided is a terminal comprising: a receiving unit that receives a band switching instruction on a downlink, in a transmission switching scheme in which at least one antenna port among a plurality of antenna ports can switch bands; and a control unit that performs random access in another band belonging to the same group as a switching destination band, when switching to a band belonging to a group with a different uplink timing advance.

Description

Terminal, base station and communication method

The present invention relates to a terminal, a base station, and a communication method in a wireless communication system.

The requirements for NR (New Radio) (also referred to as "5G"), which is the successor system to LTE (Long Term Evolution), are a large capacity system, high data transmission speed, low latency, and the simultaneous use of a large number of terminals. Techniques that satisfy connectivity, low cost, power saving, etc. are being considered (for example, Non-Patent Document 1).

Furthermore, studies have begun on 6G as the next generation wireless communication system for 5G, and it is expected that wireless quality will exceed that of 5G. For example, 6G will further increase capacity, use new frequency bands, lower latency, higher reliability, further reduce power consumption, and expand into new areas (high altitude, sea, etc.) with non-terrestrial networks. Studies are underway to expand coverage in space (space).

Studies are being conducted to strengthen uplink transmission in multicarriers. For example, an operation is being considered in which a terminal that supports up to two transmissions at the same time dynamically switches over three or four bands for uplink transmission. Here, when considering TAG (Timing Advance Group), it is assumed that switching of bands for transmitting uplink is limited.

The present invention has been made in view of the above points, and an object of the present invention is to suitably switch the band for transmitting uplink in a wireless communication system.

According to the disclosed technology, in a transmission switching method in which at least one antenna port among a plurality of antenna ports can switch bands, a receiving unit that receives a band switching instruction on a downlink, and an uplink timing A terminal is provided that includes a control unit that performs random access in another band that belongs to the same group as the band to which the advance is to be switched when switching to a band that belongs to a different group.

According to the disclosed technology, a technology is provided that allows a wireless communication system to suitably switch the band for transmitting uplink.

1 is a diagram for explaining a wireless communication system according to an embodiment of the present invention. FIG. 2 is a diagram for explaining power allocation in conventional downlink transmission. FIG. 2 is a diagram for explaining Example 1 of the embodiment of the present invention. It is a figure for explaining Example 2 of an embodiment of the present invention. It is a figure for explaining Example 3 of an embodiment of the present invention. It is a figure for explaining Example 4 of an embodiment of the present invention. 1 is a diagram showing an example of a functional configuration of a base station according to an embodiment of the present invention. 1 is a diagram illustrating an example of a functional configuration of a terminal according to an embodiment of the present invention. FIG. 1 is a diagram showing an example of the hardware configuration of a base station or a terminal according to an embodiment of the present invention. 1 is a diagram showing an example of the configuration of a vehicle according to an embodiment of the present invention.

Embodiments of the present invention will be described below 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.

Existing technologies are used as appropriate for the operation of the wireless communication system according to the embodiment of the present invention. However, the existing technology is, for example, existing LTE, but is not limited to existing LTE. Further, the term "LTE" used in this specification has a broad meaning including LTE-Advanced and a system after LTE-Advanced (eg, NR) unless otherwise specified.

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

Further, in the embodiment of the present invention, the duplex method may be a TDD (Time Division Duplex) method, an FDD (Frequency Division Duplex) method, or another method (for example, Flexible Duplex, etc.). This method may also be used.

Furthermore, in the embodiment of the present invention, "configure" the wireless parameters etc. may mean pre-configuring a predetermined value, or may mean that the base station 10 or Wireless parameters notified from the terminal 20 may also be set.

(System configuration)
FIG. 1 is a diagram for explaining a wireless communication system according to an embodiment of the present invention.
The wireless communication system according to the embodiment of the present invention includes a base station 10 and a terminal 20, as shown in FIG. Although one base station 10 and one terminal 20 are shown in FIG. 1, this is just an example, and there may be a plurality of each.

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

The base station 10 transmits a synchronization signal and system information to the terminal 20. The synchronization signals are, for example, NR-PSS and NR-SSS. System information is transmitted, for example, on NR-PBCH, and is also referred to as broadcast information. The synchronization signal and system information may be called SSB (SS/PBCH block). As shown in FIG. 1, the base station 10 transmits a control signal or data to the terminal 20 on the DL (Downlink), and receives the control signal or data from the terminal 20 on the UL (Uplink). Both the base station 10 and the terminal 20 can perform beamforming to transmit and receive signals. Further, both the base station 10 and the terminal 20 can apply MIMO (Multiple Input Multiple Output) communication to DL or UL. Further, both the base station 10 and the terminal 20 may communicate via a secondary cell (SCell) and a primary cell (PCell) using CA (Carrier Aggregation). Furthermore, the terminal 20 may communicate via a primary cell of the base station 10 and a primary SCG cell (PSCell) of another base station 10 using DC (Dual Connectivity).

The terminal 20 is a communication device equipped with a wireless communication function, such as a smartphone, a mobile phone, a tablet, a wearable terminal, or a communication module for M2M (Machine-to-Machine). As shown in FIG. 1, the terminal 20 receives control signals or data from the base station 10 via DL, and transmits control signals or data to the base station 10 via UL, thereby receiving various types of information provided by the wireless communication system. Use communication services. Furthermore, the terminal 20 receives various reference signals transmitted from the base station 10, and measures the channel quality based on the reception results of the reference signals. Note that the terminal 20 may be called a UE, and the base station 10 may be called a gNB.

Next, the status of discussions regarding base station power saving in NR Release 18 will be explained. Base station and terminal techniques to improve network energy savings from both base station transmission and reception perspectives are discussed. For example, the base station uses the potential support/feedback from the terminals and the potential assistance information to transmit and Methods are being considered to more efficiently realize dynamic and/or semi-static and/or finer-grained adaptation of reception.

(Band switching in conventional uplink transmission)
Next, band switching in conventional uplink transmission will be described.

FIG. 2 is a diagram for explaining band switching in conventional uplink transmission. Considerations are being made to enhance uplink transmission in multi-carriers. As shown in FIG. 3, an operation is being considered in which a terminal that supports up to two transmissions at the same time in Frequency Range 1 (FR1) dynamically switches the uplink transmission band over three or four bands. In the example of FIG. 3, each of the two ports can switch which of band A, band B, band C, and band D to use.

Additionally, band switching operations in dynamic uplink transmission between bands in single TAG (Timing Advance Group) and multiple TAG environments are also being considered. For example, when communicating with cells located in different locations (non-collocated cells), it is assumed that different TAGs are set for each cell. Note that a TAG is a group of bands having the same uplink timing advance.

However, conventionally, there is a problem in that instructions for band switching operations in uplink transmission are not clear when different TAGs are set for each cell.

Furthermore, when considering band switching operations in uplink transmission, there is a possibility that switching will be performed for uplink carriers that do not have a paired downlink carrier. For example, when two downlink carriers are configured and four uplink carriers that can be switched by band switching operation in uplink transmission are configured, two of the uplink carriers will be paired with the downlink carrier. Possibly not having a career.

(Summary of this embodiment)
In this embodiment, an example will be described in which instructions for band switching operations in uplink transmission are clarified when different TAGs are set for each cell. Examples 1 to 5 will be described below as examples for implementing this embodiment.

(Example 1)
In this embodiment, an example in which the terminal 20 performs band switching in uplink transmission when performing random access based on an instruction from the base station 10 will be described.

In order to perform random access, the terminal 20 may assume that a switching delay is specified when performing band switching in uplink transmission.

The terminal 20 may notify the base station 10 of the terminal capability regarding band switching in uplink transmission for performing random access. For example, the terminal 20 may notify the base station 10 of the terminal capability indicating whether to support band switching in uplink transmission for performing random access, or The base station 10 may be notified of the terminal capability indicating whether or not to support a switching delay related to band switching in transmission or the length of the switching delay.

The case where random access is executed based on an instruction from the base station 10 may be any of the following plans.

<Plan 1-1>
The terminal 20 may determine whether it is necessary to perform random access based on the uplink band scheduled by the base station 10. For example, if the terminal 20 needs to perform band switching in uplink transmission across TAGs due to uplink scheduling or the like from the base station 10, it may perform random access in the switching destination TAG.

<Plan 1-2>
It may be assumed that the terminal 20 receives an explicit instruction from the base station 10 to perform random access. For example, it may be assumed that the terminal 20 is explicitly instructed by the base station 10 to perform random access in the TAG before the base station 10 performs uplink scheduling or the like.

FIG. 3 is a diagram for explaining Example 1 of the embodiment of the present invention. FIG. 3 shows an example in which the switching destination of port 1 is band C belonging to TAG 2 which is not in use.

In case 1-1, in the case shown in FIG. 3, the terminal 20 needs to switch to band C across TAGs by scheduling uplink transmission in band C, so Random access is performed using TAG2.

Furthermore, in the case of plan 1-2, in the case shown in FIG. 3, the terminal 20 is instructed to perform random access in band C, and performs random access in TAG2, which is the switching destination.

The terminal 20 performs band switching in uplink transmission, and selects a band/carrier that performs PRACH transmission and a band/carrier in which a switching delay (switching period, etc.) occurs when performing random access (PRACH transmission). It may be assumed that a switching delay (switching period, etc.) always occurs in different bands/carriers.

That is, the terminal 20 may assume that no switching delay (switching period, etc.) occurs on the band/carrier in which PRACH transmission is performed.

Note that the terminal 20 may assume that a switching delay (switching period, etc.) always occurs in a band/carrier that performs PRACH transmission, regarding a band/carrier in which a switching delay (switching period, etc.) occurs.

In addition, unlike in the case of other channels (PUSCH, etc.), the terminal 20 can configure settings indicating in which band/carrier the switching delay (switching period, etc.) occurs in the case of the band/carrier in which PRACH transmission is performed. It may be assumed that this is not set.

(Example 2)
In this embodiment, an example will be described in which the original band combination is returned to after the random access procedure in the first embodiment is completed.

FIG. 4 is a diagram for explaining Example 2 of the embodiment of the present invention. After the random access procedure ends, the terminal 20 may switch back to the original band combination. For example, as shown in FIG. 3, the terminal 20 switches the band of port 1 from band A to band C based on an instruction to perform random access in band C, and then, after completing the random access procedure, 1 band may be cut back from band C to band A.

Note that, after switching the band of port 1 from band A to band C based on the instruction to perform random access in band C, terminal 20 switches the band of port 1 from band A to band C, and then switches the port 1 band may be cut back from band C to band A. In the terminal 20, the period may be defined in the specifications, or may be set in RRC or specified in MAC-CE, DCI, etc. Further, the period may or may not include the time required for switching back.

(Example 3)
In this embodiment, an example will be described in which synchronization of uplink transmission is executed and maintained in a TAG that may become a switching destination.

The terminal 20 may perform and maintain uplink transmission synchronization in a TAG that may be a band switching destination in uplink transmission from the TAG that it is maintaining.

The terminal 20 synchronizes the uplink transmission, and when a TAG that is a possible switching destination from the TAG that is being maintained is set, the terminal 20 synchronizes the uplink transmission by performing random access or the like. May be implemented and maintained.

FIG. 5 is a diagram for explaining Example 3 of the embodiment of the present invention. In the example shown in Fig. 5, the combination of transmission bands before switching is only TAG1, but since there is a possibility of switching to TAG2, uplink transmission synchronization is performed and maintained on TAG2 as well (i.e., random access is performed). ) may be done.

(Example 4)
In this embodiment, an example will be described in which random access is performed using another uplink carrier belonging to the same TAG as the switching destination uplink carrier.

It may be assumed that the terminal 20 determines the carrier on which to perform random access depending on whether the uplink carrier to which the switching destination is to be switched has a downlink carrier as a pair. For example, when it is necessary to perform uplink transmission synchronization on an uplink carrier that does not have a paired downlink carrier, the terminal 20 performs random access on another uplink carrier that belongs to the same TAG as the uplink carrier. May be executed.

The terminal 20 may assume that among the same TAGs, which carrier is used to perform random access is notified or specified. Furthermore, the terminal 20 may assume that other carriers of the same TAG that perform random access are limited to uplink carriers that have a paired downlink carrier. The terminal 20 may assume that RACH configuration etc. cannot be performed on an uplink carrier that does not have a paired downlink carrier.

FIG. 6 is a diagram for explaining Example 4 of the embodiment of the present invention. For example, as shown in FIG. 6, if an instruction to switch port 1 from band A to band D is notified (and uplink transmission of TAG 2 is not synchronized), terminal 20 performs random access in band C. May be executed.

In that case, the terminal 20 may first switch port 1 from band A to band C to perform random access, and then switch port 1 from band C to band D after completing the random access procedure.

(Example 5)
In this embodiment, uplink communication using a random access procedure is performed on the switching destination uplink carrier, and random access procedure is performed using a downlink carrier corresponding to another uplink carrier belonging to the same TAG as the switching destination uplink carrier. An example of performing downlink communication will be described.

It is assumed that the terminal 20 determines carriers to be used for uplink communication and downlink communication in the random access procedure, depending on whether the uplink carrier to be switched has a paired downlink carrier. It's okay. For example, when switching to an uplink carrier that does not have a paired downlink carrier, the terminal 20 transmits uplink signals related to random access using the uplink carrier, and transmits downlink signals related to random access (SSB, SIB etc.), reception and synchronization of downlink channels (PDCCH, PDSCH, etc.) by performing random access using signals/information on a downlink carrier paired with another uplink carrier belonging to the same TAG. Good too.

The terminal 20 may assume that among the same TAGs, which carrier is used to perform downlink operations related to random access is notified or specified. Furthermore, the terminal 20 may assume that RACH configuration or the like is performed on an uplink carrier that does not have a paired downlink carrier.

For example, as shown in FIG. 6, when an instruction to switch port 1 from band A to band D is notified as in the example on the previous page (and when uplink transmission of TAG 2 is not synchronized), Band D may perform uplink operations related to random access, and Band C may perform downlink operations related to random access.

The band and carrier in this embodiment may be read interchangeably. Further, the present embodiment may be applied to any of SUL (Supplementary Uplink), non-SUL, and combinations of SUL and non-SUL.

In this embodiment, an example of 2-port transmission (total of 2 bands of uplink transmission) is described, but the scope of application of this embodiment is not limited thereto. For example, 1-port transmission (total of 1 band of uplink transmission) , 3-port transmission (total of 3 bands of uplink transmission), 4-port transmission (total of 4 bands of uplink transmission), or more port transmission (total of 5 or more bands of uplink transmission).

In this embodiment, the case in which there are two TAG1 and two TAG2 is mainly illustrated, but this embodiment also includes other patterns such as TAG1:TAG2=1:3, TAG1:TAG2=3: It is also applicable to 1TAG1:TAG2:TAG3=1:1:2.

In this embodiment, regarding the ratio of the number of UL carriers (with DL carriers) to the number of UL carriers (without DL carriers), in addition to those illustrated in the above figures, other patterns (for example, in the case of 4 carriers) are used. 2:2, 1:3, 3:1, etc.).

(Device configuration)
Next, an example of the functional configuration of the base station 10 and terminal 20 that execute the processes and operations described above will be described.

<Base station 10>
FIG. 7 is a diagram showing an example of the functional configuration of the base station 10. As shown in FIG. As shown in FIG. 7, base station 10 includes a transmitting section 110, a receiving section 120, a setting section 130, and a control section 140. The functional configuration shown in FIG. 7 is only an example. As long as the operations according to the embodiments of the present invention can be executed, the functional divisions and functional parts may have any names. Furthermore, the transmitting section 110 and the receiving section 120 may be collectively referred to as a communication section.

The transmitting unit 110 includes a function of generating a signal to be transmitted to the terminal 20 side and transmitting the signal wirelessly. The receiving unit 120 includes a function of receiving various signals transmitted from the terminal 20 and acquiring, for example, information on a higher layer from the received signals. Further, the transmitter 110 has a function of transmitting NR-PSS, NR-SSS, NR-PBCH, DL/UL control signals, DCI using PDCCH, data using PDSCH, etc. to the terminal 20.

The setting unit 130 stores preset setting information and various setting information to be sent to the terminal 20 in a storage device included in the setting unit 130, and reads them from the storage device as necessary.

The control unit 140 schedules DL reception or UL transmission of the terminal 20 via the transmission unit 110. Further, the control unit 140 includes a function to perform LBT. 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. Further, the transmitting section 110 may be called a transmitter, and the receiving section 120 may be called a receiver.

<Terminal 20>
FIG. 8 is a diagram showing an example of the functional configuration of the terminal 20. As shown in FIG. 8, the terminal 20 includes a transmitting section 210, a receiving section 220, a setting section 230, and a control section 240. The functional configuration shown in FIG. 8 is only an example. As long as the operations according to the embodiments of the present invention can be executed, the functional divisions and functional parts may have any names. The transmitting section 210 and the receiving section 220 may be collectively referred to as a communication section.

The transmitter 210 creates a transmission signal from the transmission data and wirelessly transmits the transmission signal. The receiving unit 220 wirelessly receives various signals and obtains higher layer signals from the received physical layer signals. Further, the receiving unit 220 has a function of receiving NR-PSS, NR-SSS, NR-PBCH, DL/UL/SL control signals, DCI by PDCCH, data by PDSCH, etc. transmitted from the base station 10. For example, the transmitting unit 210 transmits a PSCCH (Physical Sidelink Control Channel), a PSSCH (Physical Sidelink Shared Channel), a PSDCH to another terminal 20 as D2D communication. (Physical Sidelink Discovery Channel), PSBCH (Physical Sidelink Broadcast Channel) etc., and the receiving unit 120 may receive the PSCCH, PSSCH, PSDCH, PSBCH, etc. from the other terminal 20.

The setting unit 230 stores various types of setting information received from the base station 10 or other terminals by the receiving unit 220 in a storage device included in the setting unit 230, and reads the information from the storage device as necessary. The setting unit 230 also stores setting information that is set in advance. The control unit 240 controls the terminal 20. Further, the control unit 240 includes a function to perform LBT.

The terminal of this embodiment may be configured as a terminal shown in each section below. Additionally, the following communication method may be implemented.

<Configuration related to this embodiment>
(Section 1)
In a transmission switching method in which at least one antenna port among the plurality of antenna ports can switch bands, a receiving unit that receives a band switching instruction on a downlink;
a control unit that performs random access on another band belonging to the same group as the switching destination band when switching to a band belonging to a group with a different uplink timing advance;
terminal.
(Section 2)
The control unit performs uplink communication in the random access procedure in the switching destination band, and performs downlink communication in the random access procedure in the other band.
The terminal described in paragraph 1.
(Section 3)
The control unit performs random access on the other band when a downlink band to be paired with the switching destination band is not set.
The terminal according to

item

1 or 2.
(Section 4)
In a transmission switching method in which at least one antenna port among the plurality of antenna ports can switch bands, a transmitter that transmits a band switching instruction to a terminal;
A control unit that assumes that when switching to a band belonging to a group with a different uplink timing advance, the terminal performs random access on another band belonging to the same group as the switching destination band. ,
base station.
(Section 5)
In a transmission switching scheme in which at least one antenna port of the plurality of antenna ports is capable of switching bands, receiving an instruction to switch bands on the downlink;
When switching to a band belonging to a group with a different uplink timing advance, performing random access on another band belonging to the same group as the switching destination band,
The communication method that the terminal performs.

Any of the above configurations provides a technology that enables suitable switching of the band for transmitting uplink in a wireless communication system. According to the first item, random access can be performed in another band belonging to the same group as the switching destination band. According to the second clause, it is possible to perform uplink communication in a random access procedure in a switching destination band, and to perform downlink communication in a random access procedure in another band. According to item 3, when the switching destination band has no paired downlink band set, random access can be performed in another band.

(Hardware configuration)
The block diagrams (FIGS. 7 and 8) used to explain the above embodiments show blocks in functional units. 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 one physically or logically coupled device, or may be realized using two or more physically or logically separated devices directly or indirectly (e.g. , wired, wireless, etc.) and may be realized using a plurality of these devices. The functional block may be realized by combining software with the one device or the plurality of devices.

Functions include judgment, decision, judgment, calculation, calculation, processing, derivation, investigation, exploration, confirmation, reception, transmission, output, access, resolution, selection, selection, establishment, comparison, assumption, expectation, consideration, These include, but are not limited to, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assigning. I can't do it. For example, a functional block (configuration unit) that performs transmission is called a transmitting unit or a transmitter. In either case, as described above, the implementation method is not particularly limited.

For example, the base station 10, terminal 20, etc. in an embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method of the present disclosure. FIG. 9 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 terminal 20 described above are 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. Good too.

Note that in the following description, the word "apparatus" can be read 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 each device shown in the figure, or may be configured not to include some of the devices.

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

The processor 1001, for example, operates an operating system to control the entire computer. The processor 1001 may be configured with a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic unit, registers, and the like. For example, the above-described control unit 140, control unit 240, etc. may be implemented by the processor 1001.

Furthermore, the processor 1001 reads programs (program codes), software modules, data, etc. from at least one of the auxiliary storage device 1003 and the communication device 1004 to the storage device 1002, and executes various processes in accordance with these. As the program, a program that causes a computer to execute at least part of the operations described in the above embodiments is used. For example, the control unit 140 of the base station 10 shown in FIG. 7 may be realized by a control program stored in the storage device 1002 and operated on the processor 1001. Further, for example, the control unit 240 of the terminal 20 shown in FIG. 8 may be realized by a control program stored in the storage device 1002 and operated on the processor 1001. Although the various processes described above have been described as being executed by one processor 1001, they may be executed by two or more processors 1001 simultaneously or sequentially. Processor 1001 may be implemented by one or more chips. Note that the program may be transmitted from a network via a telecommunications line.

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

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

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 a network device, network controller, network card, communication module, etc., for example. The communication device 1004 includes, for example, a high frequency switch, a duplexer, a filter, a frequency synthesizer, etc. in order to realize at least one of frequency division duplex (FDD) and time division duplex (TDD). It may be composed of. For example, a transmitting/receiving antenna, an amplifier section, a transmitting/receiving section, a transmission line interface, etc. may be realized by the communication device 1004. The transmitting and receiving unit may be physically or logically separated into a transmitting unit and a receiving unit.

The input device 1005 is an input device (eg, keyboard, mouse, microphone, switch, button, sensor, etc.) that accepts input from the outside. The output device 1006 is an output device (for example, a display, a speaker, an LED lamp, etc.) that performs output to the outside. Note that the input device 1005 and the output device 1006 may have an integrated configuration (for example, a touch panel).

Further, 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 for each device.

The base station 10 and the terminal 20 also include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), and a field programmable gate array (FPGA). A part or all of each functional block may be realized by the hardware. For example, processor 1001 may be implemented using at least one of these hardwares.

FIG. 10 shows an example of the configuration of the vehicle 2001. As shown in FIG. 10, the vehicle 2001 includes a drive unit 2002, a steering unit 2003, an accelerator pedal 2004, a brake pedal 2005, a shift lever 2006, a front wheel 2007, a rear wheel 2008, an axle 2009, an electronic control unit 2010, and various sensors 2021 to 2029. , an information service section 2012 and a communication module 2013. Each aspect/embodiment described in this disclosure may be applied to a communication device mounted on vehicle 2001, for example, may be applied to communication module 2013.

The drive unit 2002 is composed of, for example, an engine, a motor, or a hybrid of an engine and a motor. The steering unit 2003 includes at least a steering wheel (also referred to as a steering wheel), 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.

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

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

The information service department 2012 controls various devices such as car navigation systems, audio systems, speakers, televisions, and radios that provide (output) various information such as driving information, traffic information, and entertainment information, and these devices. It is composed of one or more ECUs. The information service unit 2012 provides various multimedia information and multimedia services to the occupants of the vehicle 2001 using information acquired from an external device via the communication module 2013 and the like.

The information service department 2012 may include an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, a touch panel, etc.) that accepts input from the outside, and an output device that performs output to the outside (for example, display, speaker, LED lamp, touch panel, etc.).

The driving support system unit 2030 includes a millimeter wave radar, LiDAR (Light Detection and Ranging), a camera, a positioning locator (for example, GNSS, etc.), map information (for example, a high-definition (HD) map, an autonomous vehicle (AV) map, etc.) ), gyro systems (e.g., IMU (Inertial Measurement Unit), INS (Inertial Navigation System), etc.), AI (Artificial Intelligence) chips, and AI processors that prevent accidents and reduce the driver's driving burden. The system is comprised of various devices that provide functions for the purpose and one or more ECUs that control these devices. Further, the driving support system unit 2030 transmits and receives various information via the communication module 2013, and realizes a driving support function or an automatic driving function.

Communication module 2013 can communicate with microprocessor 2031 and components of vehicle 2001 via a communication port. For example, the communication module 2013 communicates with the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, front wheels 2007, rear wheels 2008, axle 2009, electronic Data is transmitted and received between the microprocessor 2031, memory (ROM, RAM) 2032, and sensors 2021 to 29 in the control unit 2010.

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 external devices. For example, various information is transmitted and received with an 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.

The communication module 2013 receives signals from the various sensors 2021 to 2029 described above that are input to the electronic control unit 2010, information obtained based on the signals, and input from the outside (user) obtained via the information service unit 2012. At least one of the information based on the information may be transmitted to an external device via wireless communication. The electronic control unit 2010, various sensors 2021-2029, information service unit 2012, etc. may be called an input unit that receives input. For example, the PUSCH transmitted by the communication module 2013 may include information based on the above input.

The communication module 2013 receives various information (traffic information, signal information, inter-vehicle information, etc.) transmitted from an external device, and displays it on the information service section 2012 provided in the vehicle 2001. The information service unit 2012 is an output unit that outputs information (for example, outputs information to devices such as a display and a speaker based on the PDSCH (or data/information decoded from the PDSCH) received by the communication module 2013). may be called.

The communication module 2013 also stores various information received from external devices into a memory 2032 that can be used by the microprocessor 2031. Based on the information stored in the memory 2032, the microprocessor 2031 controls the drive section 2002, steering section 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, front wheel 2007, rear wheel 2008, and axle 2009 provided in the vehicle 2001. , sensors 2021 to 2029, etc. may be controlled.

(Supplementary information on the embodiment)
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, modifications, alternatives, replacements, etc. Probably. Although the invention has been explained using specific numerical examples to facilitate understanding of the invention, unless otherwise specified, these numerical values are merely examples, and any appropriate values may be used. The classification of items in the above explanation is not essential to the present invention, and matters described in two or more items may be used in combination as necessary, and matters described in one item may be used in another item. may be applied to the matters described in (unless inconsistent). 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 a plurality of functional sections may be physically performed by one component, or the operations of one functional section may be physically performed by a plurality of components. Regarding the processing procedures described in the embodiments, the order of processing may be changed as long as there is no contradiction. Although the base station 10 and the terminal 20 have been described using functional block diagrams for convenience of process description, such devices may be implemented in hardware, software, or a combination thereof. Software operated by the processor included in the base station 10 according to the embodiment of the present invention and software operated by the processor included in the terminal 20 according to the embodiment of the present invention are respectively random access memory (RAM), flash memory, and read-only memory. (ROM), EPROM, EEPROM, register, hard disk (HDD), removable disk, CD-ROM, database, server, or any other suitable storage medium.

Furthermore, the notification of information is not limited to the aspects/embodiments described in this disclosure, and may be performed using other methods. For example, the notification of information may be physical layer signaling (e.g., DCI (Downlink Control Information), UCI (Uplink Control Information)), upper 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. Further, RRC signaling may be called an RRC message, and may be, for example, an RRC Connection Setup message, an RRC Connection Reconfiguration message, or the like.

Each aspect/embodiment described in this disclosure is LTE (Long Term Evolution), LTE-A (LTE-Advanced), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication system), 5G (5th generation mobile communication system). system), 6th generation mobile communication system (6G), xth generation mobile communication system (xG) (xG (x is an integer or decimal number, for example)), FRA (Future Radio Access), NR (new Radio), New radio access ( NX), Future generation radio access (FX), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802 Systems that utilize .16 (WiMAX (registered trademark)), IEEE 802.20, UWB (Ultra-WideBand), Bluetooth (registered trademark), and other appropriate systems, and that are extended, modified, created, and defined based on these. The present invention may be applied to at least one of the next generation systems. Furthermore, a combination of a plurality of systems may be applied (for example, a combination of at least one of LTE and LTE-A and 5G).

The order of the processing procedures, sequences, flowcharts, etc. of each aspect/embodiment described in this specification may be changed as long as there is no contradiction. For example, the methods described in this disclosure use an example order to present elements of the various steps and are not limited to the particular order presented.

In this specification, specific operations performed by the base station 10 may be performed by its upper node in some cases. In a network consisting of one or more network nodes including a base station 10, various operations performed for communication with a terminal 20 are performed by the base station 10 and other network nodes other than the base station 10. It is clear that this can be done by at least one of the following: for example, MME or S-GW (possible, but not limited to). Although the case where there is one network node other than the base station 10 is illustrated above, the other network node may be a combination of multiple other network nodes (for example, MME and S-GW). .

The information, signals, etc. described in this disclosure can be output from an upper layer (or lower layer) to a lower layer (or upper layer). It may be input/output via multiple network nodes.

The input/output information may be stored in a specific location (for example, memory) or may be managed using a management table. Information etc. to be input/output may be overwritten, updated, or additionally written. The output information etc. may be deleted. The input information etc. may be transmitted to other devices.

The determination in the present disclosure may be performed based on a value represented by 1 bit (0 or 1), a truth value (Boolean: true or false), or a comparison of numerical values (e.g. , comparison with a predetermined value).

Software includes instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, whether referred to as software, firmware, middleware, microcode, hardware description language, or by any other name. , should be broadly construed to mean an application, software application, software package, routine, subroutine, object, executable, thread of execution, procedure, function, etc.

Additionally, software, instructions, information, etc. may be sent and received via a transmission medium. For example, if the software uses wired technology (coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), etc.) and/or wireless technology (infrared, microwave, etc.) to create a website, When transmitted from a server or other remote source, these wired and/or wireless technologies are included within the definition of transmission medium.

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., which may be referred to throughout the above description, may refer to voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, light fields or photons, or any of these. It may also be represented by a combination of

Note that terms explained 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 the channel and the symbol may be a signal. Also, the signal may be a message. Further, a component carrier (CC) may also be called a carrier frequency, a cell, a frequency carrier, or the like.

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

In addition, the information, parameters, etc. described in this disclosure may be expressed using absolute values, relative values from a predetermined value, or using other corresponding information. may be expressed. For example, radio resources may be indicated by an index.

The names used for the parameters mentioned above are not restrictive in any respect. Furthermore, the mathematical formulas etc. using these parameters may differ from those explicitly disclosed in this disclosure. Since the various channels (e.g. PUCCH, PDCCH, etc.) and information elements may be identified by any suitable designation, the various names assigned to these various channels and information elements are in no way exclusive designations. isn't it.

In this disclosure, "Base Station (BS)," "wireless base station," "base station," "fixed station," "NodeB," "eNodeB (eNB)," and "gNodeB ( gNB)”, “access point”, “transmission point”, “reception point”, “transmission/reception point”, “cell”, “sector”, Terms such as "cell group," "carrier," "component carrier," and the like may be used interchangeably. A base station is sometimes referred to by terms such as macrocell, small cell, femtocell, and picocell.

A base station can accommodate one or more (eg, three) cells. If 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 is divided into multiple subsystems (e.g., small indoor base stations (RRHs)). Communication services can also be provided by Remote Radio Head). The term "cell" or "sector" refers to part or all of the coverage area of a base station and/or base station subsystem that provides communication services in this coverage.

In the present disclosure, the base station transmitting information to the terminal may be read as the base station instructing the terminal to control/operate based on the information.

In this disclosure, terms such as "Mobile Station (MS)," "user terminal," "User Equipment (UE)," and "terminal" may be used interchangeably. .

A mobile station is defined by a person 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 It may also be referred to as a terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable terminology.

At least one of a base station and a mobile station may be called a transmitting device, a receiving device, a communication device, etc. Note that at least one of the base station and the mobile station may be a device mounted on a mobile body, the mobile body itself, or the like. The moving object may be a vehicle (for example, a car, an airplane, etc.), an unmanned moving object (for example, a drone, a self-driving car, etc.), or a robot (manned or unmanned). ). Note that at least one of the base station and the mobile station includes devices that do not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an IoT (Internet of Things) device such as a sensor.

Additionally, the base station in the present disclosure may be replaced by a user terminal. For example, communication between a base station and a user terminal is replaced with communication between a plurality of terminals 20 (for example, it may be called D2D (Device-to-Device), V2X (Vehicle-to-Everything), etc.). Regarding the configuration, each aspect/embodiment of the present disclosure may be applied. In this case, the terminal 20 may have the functions that the base station 10 described above has. Further, words such as "up" and "down" may be replaced with words corresponding to inter-terminal communication (for example, "side"). For example, uplink channels, downlink channels, etc. may be replaced with side channels.

Similarly, the user terminal in the present disclosure may be replaced with a base station. In this case, the base station may have the functions that the user terminal described above has.

As used in this disclosure, the terms "determining" and "determining" may encompass a wide variety of operations. "Judgment" and "decision" include, for example, judging, calculating, computing, processing, deriving, investigating, looking up, search, and inquiry. (e.g., searching in a table, database, or other data structure), and regarding an ascertaining as a "judgment" or "decision." In addition, "judgment" and "decision" refer to receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, and access. (accessing) (e.g., accessing data in memory) may include considering something as a "judgment" or "decision." In addition, "judgment" and "decision" refer to resolving, selecting, choosing, establishing, comparing, etc. as "judgment" and "decision". may be included. In other words, "judgment" and "decision" may include regarding some action as having been "judged" or "determined." Further, "judgment (decision)" may be read as "assuming", "expecting", "considering", etc.

The terms "connected", "coupled", or any variations thereof, refer to any connection or coupling, direct or indirect, between two or more elements and to each other. It may include the presence of one or more intermediate elements between two elements that are "connected" or "coupled." The bonds or connections between elements may be physical, logical, or a combination thereof. For example, "connection" may be replaced with "access." As used in this disclosure, two elements may include one or more electrical wires, cables, and/or printed electrical connections, as well as in the radio frequency domain, as some non-limiting and non-inclusive examples. , electromagnetic energy having wavelengths in the microwave and optical (both visible and non-visible) ranges.

The reference signal can also be abbreviated as RS (Reference Signal), and may be called a pilot depending on the applied standard.

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

As used in this disclosure, any reference to elements using the designations "first," "second," etc. does not generally limit the amount or order of those elements. These designations may be used in this disclosure as a convenient way to distinguish between two or more elements. Thus, reference to a first and second element does not imply that only two elements may be employed or that the first element must precede the second element in any way.

"Means" in the configurations of each of the above devices may be replaced with "unit", "circuit", "device", etc.

Where "include", "including" and variations thereof are used in this disclosure, these terms, like the term "comprising," are inclusive. It is intended that Furthermore, the term "or" as used in this disclosure is not intended to be exclusive or.

A radio frame may be composed of one or more frames in the time domain. Each frame or frames in the time domain may be called a subframe. A subframe may also be composed of one or more slots in the time domain. A subframe may have a fixed time length (eg, 1 ms) that does not depend on numerology.

The numerology may be a communication parameter applied to the transmission and/or reception of a certain signal or channel. Numerology includes, for example, subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, radio frame configuration, and transmitter/receiver. It may also indicate at least one of a specific filtering process performed in the frequency domain, a specific windowing process performed by the transceiver in the time domain, and the like.

A slot may 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 slot may be a unit of time based on numerology.

A slot may include multiple mini-slots. Each minislot may be made up of one or more symbols in the time domain. Furthermore, a mini-slot may also be called a sub-slot. A minislot may be made up of fewer symbols than a slot. PDSCH (or PUSCH) transmitted in time units larger than minislots may be referred to as PDSCH (or PUSCH) mapping type A. PDSCH (or PUSCH) transmitted using minislots may be referred to as PDSCH (or PUSCH) mapping type B.

Radio frames, subframes, slots, minislots, and symbols all represent time units when transmitting signals. Other names may be used for the radio frame, subframe, slot, minislot, and symbol.

For example, one subframe may be called a transmission time interval (TTI), multiple consecutive subframes may be called a TTI, and one slot or one minislot may be called a TTI. It's okay. In other words, at least one of the subframe and TTI may be a subframe (1ms) in existing LTE, a period shorter than 1ms (for example, 1-13 symbols), or a period longer than 1ms. It may be. Note that the unit representing the TTI may be called a slot, minislot, etc. instead of a subframe.

Here, TTI refers to, for example, the minimum time unit for scheduling in wireless communication. For example, in the LTE system, a base station performs scheduling to allocate radio resources (frequency bandwidth, transmission power, etc. that can be used by each terminal 20) to each terminal 20 on a TTI basis. Note that the definition of TTI is not limited to this.

The TTI may be a transmission time unit of a channel-coded data packet (transport block), a code block, a codeword, etc., or may be a processing unit of scheduling, link adaptation, etc. Note that when a TTI is given, the time interval (for example, the number of symbols) to which transport blocks, code blocks, code words, etc. are actually mapped may be shorter than the TTI.

Note that when one slot or one minislot is called a TTI, one or more TTIs (that is, one or more slots or one or more minislots) may be the minimum time unit for scheduling. Further, the number of slots (minislot number) that constitutes the minimum time unit of the scheduling may be controlled.

A TTI having a time length of 1 ms may be called a normal TTI (TTI in LTE Rel. 8-12), normal TTI, long TTI, normal subframe, normal subframe, long subframe, slot, etc. A TTI that is shorter than the normal TTI may be referred to as an abbreviated TTI, short TTI, partial or fractional TTI, shortened subframe, short subframe, minislot, subslot, slot, etc.

Note that long TTI (e.g., normal TTI, subframe, etc.) may be read as TTI with a time length exceeding 1 ms, and short TTI (e.g., shortened TTI, etc.) may be replaced with TTI having a time length of less than the long TTI and 1 ms. It may also be read as a TTI having the above TTI length.

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

Additionally, the time domain of an RB may include one or more symbols, and may be one slot, one minislot, one subframe, or one TTI in length. One TTI, one subframe, etc. may each be composed of one or more resource blocks.

Note that one or more RBs include physical resource blocks (PRBs), sub-carrier groups (SCGs), resource element groups (REGs), PRB pairs, RB pairs, etc. May be called.

Additionally, a resource block may be configured by one or more resource elements (REs). For example, 1 RE may be a radio resource region of 1 subcarrier and 1 symbol.

A bandwidth part (BWP) (which may also be called a partial bandwidth or the like) may represent a subset of consecutive common resource blocks (RBs) for a certain numerology in a certain carrier. Here, the common RB may be specified by an RB index based on a common reference point of the carrier. PRBs may be defined in a BWP and numbered within that BWP.

The BWP may include a UL BWP (UL BWP) and a DL BWP (DL BWP). One or more BWPs may be configured for the terminal 20 within one carrier.

At least one of the configured BWPs may be active, and the terminal 20 does not need to assume that it transmits or receives a given signal/channel outside the active BWP. Note that "cell", "carrier", etc. in the present disclosure may be replaced with "BWP".

The structures of radio frames, subframes, slots, minislots, symbols, etc. described above are merely examples. For example, 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 symbols included in an RB, Configurations such as the number of subcarriers, the number of symbols in a TTI, the symbol length, and the cyclic prefix (CP) length can be changed in various ways.

In this disclosure, when articles are added by translation, such as a, an, and the in English, the present disclosure may include that the nouns following these articles are plural.

In the present disclosure, the term "A and B are different" may mean "A and B are different from each other." Note that the term may also mean that "A and B are each different from C". Terms such as "separate" and "coupled" may also be interpreted similarly to "different."

Each aspect/embodiment described in this disclosure may be used alone, in combination, or may be switched and used in accordance with execution. In addition, notification of prescribed information (for example, notification of "X") is not limited to being done explicitly, but may also be done implicitly (for example, not notifying the prescribed information). Good too.

Although the present disclosure has been described in detail above, it is clear for those skilled in the art that the present disclosure is not limited to the embodiments described in the present disclosure. The present disclosure can be implemented as modifications and variations without departing from the spirit and scope of the present disclosure as determined by the claims. Therefore, the description of the present disclosure is for the purpose of illustrative explanation and is not intended to have any limiting meaning on the present disclosure.

10 Base station 110 Transmitting section 120 Receiving section 130 Setting section 140 Control section 20 Terminal 210 Transmitting section 220 Receiving section 230 Setting section 240 Control section 1001 Processor 1002 Storage device 1003 Auxiliary storage device 1004 Communication device 1005 Input device 1006 Output device 2001 Vehicle 2002 Driving part 2003 Restoration Part 2004 Axel Pedal 2005 Brake Pedal 2006 Shift Lever 2007 Front wheels 2008 Bearing 2009 Axis 2010 Electronic Control Division 2012 Electronic Control Division 20133 Communication Modular 2021 Current sensor 2022 Round Sensor 2023 Air pressure sensor 2024 vehicle speed Sensen Sa 2025 acceleration sensor 2026 brake Pedal sensor 2027 Shift lever sensor 2028 Object detection sensor 2029 Accelerator pedal sensor 2030 Driving support system section 2031 Microprocessor 2032 Memory (ROM, RAM)
2033 Communication port (IO port)

Claims

In a transmission switching method in which at least one antenna port among the plurality of antenna ports can switch bands, a receiving unit that receives a band switching instruction on a downlink;
a control unit that performs random access on another band belonging to the same group as the switching destination band when switching to a band belonging to a group with a different uplink timing advance;
terminal.
The control unit performs uplink communication in the random access procedure in the switching destination band, and performs downlink communication in the random access procedure in the other band.
The terminal according to claim 1.
The control unit performs random access on the other band when a downlink band to be paired with the switching destination band is not set.
The terminal according to claim 1.
In a transmission switching method in which at least one antenna port among the plurality of antenna ports can switch bands, a transmitter that transmits a band switching instruction to a terminal;
A control unit that assumes that when switching to a band belonging to a group with a different uplink timing advance, the terminal performs random access on another band belonging to the same group as the switching destination band. ,
base station.
In a transmission switching scheme in which at least one antenna port of the plurality of antenna ports is capable of switching bands, receiving an instruction to switch bands on the downlink;
When switching to a band belonging to a group with a different uplink timing advance, performing random access on another band belonging to the same group as the switching destination band,
The communication method that the terminal performs.