JP7438245B2 - Terminal and communication method - Google Patents

Description

The present invention relates to a terminal 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 simultaneous support for a large number of terminals. Techniques that satisfy connectivity, low cost, power saving, etc. are being considered (for example, Non-Patent Document 1).

Dynamic spectrum sharing (DSS) technology that allows LTE and NR to coexist within the same band is being considered (for example, Non-Patent Document 2). By allowing different RATs (Radio Access Technologies) to coexist on a single carrier, it becomes possible to flexibly respond to traffic demands at the time of system generation switching.

3GPP TS 38.300 V15.8.0 (2019-12) 3GPP TSG RAN Meeting #86 RP-192678 (2019-12)

In the current DSS specifications, signals for synchronization are transmitted to LTE terminals and NR terminals, respectively. That is, since signals having similar functions are sent to each RAT (Radio Access Technology), the overhead in the entire system increases.

The present invention has been made in view of the above points, and an object of the present invention is to reduce the overhead when a plurality of RATs (Radio Access Technologies) coexist on a single carrier in a wireless communication system.

According to the disclosed technology, a receiver receives a first signal of a first RAT (Radio Access Technology), and performs QCL (Quasi-CLI) between the first signal and a second signal of a second RAT. a control unit that synchronizes with a cell of the second RAT using a co-location relationship , and the receiving unit is configured to transmit a third signal of a third RAT to data decoding in the second RAT. You will be provided with a device to use .

According to the disclosed technology, it is possible to reduce overhead when a plurality of RATs (Radio Access Technologies) coexist on a single carrier in a wireless communication system.

1 is a diagram showing a configuration example of a wireless communication system according to an embodiment of the present invention. FIG. 2 is a diagram illustrating an example of downlink channel arrangement using DSS. FIG. 2 is a diagram illustrating an example of uplink channel arrangement using DSS. FIG. 3 is a diagram showing an example (1) of frequency allocation in DSS. It is a figure showing example (2) of frequency allocation in DSS. FIG. 2 is a diagram illustrating an example of LTE downlink channel arrangement. FIG. 3 is a diagram illustrating an example of NR downlink channel arrangement. FIG. 3 is a diagram illustrating an example of LTE and NR downlink channel arrangement using DSS. FIG. 3 is a diagram illustrating an example of QCL relationships between reference signals. It is a flowchart for explaining the example of operation concerning synchronization in an embodiment of the present invention. It is a flowchart for explaining the example of operation concerning QCL setting in an embodiment of the present invention. 1 is a diagram showing an example of a functional configuration of a base station 10 in an embodiment of the present invention. It is a diagram showing an example of a functional configuration of a terminal 20 in an embodiment of the present invention. FIG. 2 is a diagram showing an example of the hardware configuration of a base station 10 or a terminal 20 in an embodiment of the present invention.

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 techniques 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.

FIG. 1 is a diagram showing a configuration example of a wireless communication system according to an embodiment of the present invention. A wireless communication system according to an 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. Base station 10 transmits a synchronization signal and system information to 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 secondary 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.

An example of a DSS (Dynamic Spectrum Sharing) technology that allows LTE and NR to coexist in the same band will be described below. DSS technology allows different RATs (Radio Access Technologies) to coexist on a single carrier, making it possible to flexibly respond to traffic demands at the time of system generation switching.

FIG. 2 is a diagram illustrating an example of downlink channel arrangement using DSS. The time domain shown in FIG. 2 corresponds to one subframe of LTE. As shown in FIG. 2, "LTE-CRS (Cell specific reference signal)", "LTE-PDCCH", and "LTE-PDSCH" are transmitted as LTE signals or channels in the downlink. Furthermore, as shown in FIG. 2, "NR-PDCCH" and "NR-PDSCH" are transmitted as NR channels in the downlink. For example, although not shown, physical channels and signals other than these may be arranged. For example, "NR-PDSCH" may include resources where a DM-RS (Demodulation reference signal) is allocated. For example, as shown in FIG. 2, "LTE-CRS" may be arranged within the "NR-PDSCH" region.

FIG. 3 is a diagram illustrating an example of uplink channel arrangement using DSS. As shown in FIG. 3, LTE and NR uplink channels or signals are arranged to share a frequency band. As shown in FIG. 3, for example, from low frequency to high frequency, "NR-PUCCH", "LTE-PUCCH", "LTE-PRACH", "LTE-PUSCH", "NR-PUSCH", "NR- PRACH," "LTE-PUSCH," "LTE-PUCCH," and "NR-PUCCH." Further, "LTE-SRS (Sounding Reference Signal)" or "NR-SRS" may be arranged in the frequency region where "LTE-PUSCH", "NR-PUSCH", and "NR-PRACH" are arranged.

Note that although the above example shows an example in which LTE and NR are frequency multiplexed, other multiplexing methods may be used, such as time multiplexing or spatial multiplexing.

FIG. 4 is a diagram showing an example (1) of frequency allocation in DSS. As shown in FIG. 4, a BS (Base station) provides LTE on carrier #1, LTE and NR on carrier #2, NR on carrier #3, and NR on carrier #4.

For example, for an NR UE (User Equipment), as shown in pattern 1 shown in FIG. An SCell (Secondary Cell) may be placed in #3, and an SCell may be placed in carrier #4. Furthermore, for example, for an NR UE, as in pattern 2 shown in FIG. good. Further, for example, for an NR UE, an NR PCell may be placed on carrier #2, an SCell on carrier #3, and an SCell on carrier #4, as in pattern 3 shown in FIG. 4.

For example, for an LTE UE, an LTE PCell may be placed on carrier #1, as in pattern 1 shown in FIG. 4. Further, for example, for an LTE UE, an LTE PCell may be placed on carrier #2 as in pattern 2 shown in FIG. 4 . Further, for example, for an LTE UE, an LTE PCell may be placed on carrier #1 and an LTE SCell may be placed on carrier #2, as in pattern 3 shown in FIG. Furthermore, for example, for an LTE UE, an LTE SCell may be placed on carrier #1 and an LTE PCell may be placed on carrier #2, as in pattern 4 shown in FIG.

FIG. 5 is a diagram showing an example (2) of frequency allocation in DSS. As shown in FIG. 5, the BS provides LTE and NR on carrier #1, NR on carrier #2, and NR on carrier #3.

For example, for an NR UE, as in pattern 1 shown in FIG. 5, an LTE PCell and an NR SCell are placed on carrier #1, an NR PSCell is placed on carrier #2, and an NR SCell is placed on carrier #3. You can. Also, for example, for an NR UE, as shown in pattern 2 shown in FIG. may be placed. Furthermore, for example, for an NR UE, as in pattern 3 shown in FIG. good.

For example, for an LTE UE, an LTE PCell may be placed on carrier #1, as in pattern 1 shown in FIG. 5.

Table 1 is an example showing LTE and NR synchronization signals or reference signals for each purpose.

As shown in Table 1, LTE and NR each define signals for the same or similar purposes. Purpose may also mean use. For coarse synchronization, LTE-PSS/SSS is used in LTE, and NR-PSS/SSS is used in NR. For highly accurate synchronization, CRS is used in LTE, and NR-TRS is used in NR. NR-TRS may also be called NR-CSI (Channel State Information)-RS for tracking. For downlink channel estimation, LTE-CRS/CSI-RS is used in LTE, and NR-CSI-RS is used in NR. For uplink channel estimation, LTE-SRS is used in LTE, and NR-SRS is used in NR. For phase noise estimation, a signal for this purpose is not set in LTE, and NR-PT (Phase tracking)-RS is used in NR. For data decoding, LTE-CRS/DM-RS is used in LTE, and NR-DM-RS is used in NR. For broadcast signal decoding, CRS is used in LTE, and NR-PBCH-DM-RS is used in NR.

Note that even if the names are the same, the configurations of the physical signals may be different. For example, LTE CSI-RS and NR CSI-RS have different physical signal configurations.

FIG. 6 is a diagram illustrating an example of LTE downlink channel arrangement. The time domain shown in FIG. 6 corresponds to one LTE subframe, and the frequency domain corresponds to one resource block. As shown in FIG. 6, LTE-CRS is transmitted as a reference signal and LTE-PDCCH is transmitted as a control signal.

FIG. 7 is a diagram illustrating an example of NR downlink channel arrangement. The time domain shown in FIG. 7 corresponds to one NR slot, the frequency domain corresponds to one resource block, and the subcarrier interval is 15 kHz. As shown in FIG. 7, NR-DM-RS is transmitted as a reference signal and NR-PDCCH is transmitted as a control signal.

FIG. 8 is a diagram illustrating an example of LTE and NR downlink channel arrangement using DSS. In the current DSS specifications, signals for the same purpose are transmitted to LTE terminals and NR terminals, respectively. As shown in FIG. 8, when LTE signals and NR signals are transmitted respectively, overhead increases and resources for transmitting data decrease.

Therefore, overhead can be reduced by sharing some signals and/or channels between RATs. For example, the terminal 20 may receive an NR signal/channel using LTE-CRS. Further, for example, the terminal 20 may establish synchronization with the NR cell using LTE-SS.

QCL (Quasi-co-location) that defines the relationship between reference signals will be explained below. Multiple types of QCL are defined. QCL type A relates to Doppler shift, Doppler spread, average delay, and delay rate. QCL type B relates to Doppler shift and Doppler spread. QCL type C concerns Doppler shift, average delay. QCL type D relates to spatial reception parameters (Spatial Rx parameters). Therefore, QCL type A, B or C is QCL information related to time or frequency synchronization processing, and QCL type D is QCL information related to beam control.

Here, for example, if a certain SS block and a certain CSI-RS are of QCL type D, the terminal 20 assumes that the SS block and the CSI-RS are transmitted from the base station 10 using the same DL beam. can be received by applying the same receive beamforming. In the following description, "QCL type D" will be mainly explained, but it may be replaced with QCL type A, B, or C as appropriate. Note that hereinafter, time synchronization, frequency synchronization, and beam control may be referred to as "synchronization" or "synchronization processing" without distinction.

FIG. 9 is a diagram illustrating an example of QCL relationships between reference signals. As described above, QCL is defined between two signals, and QCL is defined when the radio parameters between the signals can be considered to be the same. FIG. 9 shows an example of QCL association. The QCL relationship has a parent-child relationship of source and destination. For example, as shown in FIG. 9, the source of QCL types C and D is SSB, and the destination is TRS (Tracking Reference Signal or CSI-RS for tracking). Further, the source of QCL types A and D is TRS, and the destination is CSI-RS, PDCCH DM-RS (Demodulation reference signal), and PDSCH DM-RS.

In the existing technology, information indicating a QCL source signal is notified for a certain signal. For example, the base station 10 notifies the terminal 20 that the TRS, which is the destination, is QCL type C and D with SSB as the source. Signaling to notify information regarding QCL may be performed by a TCI (Transmission configuration indicator).

FIG. 10 is a flowchart for explaining an operation example related to synchronization in the embodiment of the present invention. In step S11, the terminal 20 starts an NR cell addition operation. In step S12, the terminal 20 performs synchronization with the NR cell using the LTE signal. As shown in FIG. 11, in step S12, the terminal 20 may use a QCL setting in which the LTE signal is the source and the NR signal is the destination.

FIG. 11 is a flowchart for explaining an example of operation related to QCL setting in the embodiment of the present invention. In step S21, QCL settings are performed in which the LTE signal is the QCL source and the NR signal is the QCL destination. The QCL settings may be notified from the base station 10 to the terminal 20. Subsequently, the terminal 20 performs synchronization with the NR cell using the QCL settings (S22).

For example, the following LTE signals A) to D) may be used as the QCL source.
A) SS (part or all of PSS and SSS)
B) PBCH reference signal C) CRS
D) CSI-RS
E) DM-RS

For example, the following NR signals a) to d) may be used as the QCL source.
a) SSB (Part or all of PSS, SSS, PBCH-DM-RS)
b) DM-RS (part or all of PDSCH DM-RS, PDCCH DM-RS)
c) CSI-RS
d) TRS (CSI-RS for tracking)

For example, the definition of the QCL relationship described above may be as shown in 1) to 3) below.
1) The QCL relationship may include some or all of QCL type A, type B, type C, and type D defined in NR.
2) The QCL relationship may be defined as QCL defined in LTE. Parameters related to QCL may include some or all of delay spread, Doppler spread, Doppler shift, average gain, average delay, spatial Rx parameters. good.
3) Parameters related to QCL may be newly defined parameters other than those described above.

The terminal 20 may assume that the same type of reference signal is QCL by default. For example, LTE-PSS/SSS may be assumed to be NR-PSS/SSS and QCL. For example, LTE-CRS may be assumed to be NR-TRS and QCL. For example, it may be assumed that the LTE signal and the NR signal shown in Table 1, which have the same purpose or use, are QCL.

Although the embodiments of the present invention have been described using the case where the first RAT and the second RAT are DSS as a main example, they do not necessarily need to be DSS. For example, when DSS is not applied, the second RAT may establish QCL based on the first RAT's signal.

Embodiments of the present invention can be applied regardless of uplink, downlink, transmission, or reception. Uplink signals and channels and downlink signals and channels can be read interchangeably. Uplink feedback information and downlink control signaling can be read interchangeably.

The signaling from the base station 10 to the terminal 20 or from the terminal 20 to the base station 10 in the above embodiments is not limited to an explicit method, and may be notified by an implicit method. good. Alternatively, no signaling may be performed and it may be uniquely defined in the specifications.

The signaling from the base station 10 to the terminal 20 or from the terminal 20 to the base station 10 in the above embodiments may be different layer signaling such as RRC signaling, MAC-CE signaling, or DCI signaling. , signaling using broadcast information (MIB (Master Information Block), SIB (System Information Block)). Further, for example, RRC signaling and DCI signaling may be combined, RRC signaling and MAC-CE signaling may be combined, or RRC signaling, MAC-CE signaling, and DCI signaling may be combined.

Although the above-mentioned embodiment has been described as LTE and NR, it may also be applied to a future communication system (for example, called "6G") than NR. For example, the embodiments described above may be applied to NR and 6G coexistence technologies.

Similarly, next generation systems may generally receive signals and/or channels of previous generation systems. For example, a system may span multiple generations. For example, a certain system may apply a reference signal from a system two generations ago. Reference signals of multiple generations may be applied. For example, in a certain system, a reference signal from a system two generations ago may be used for synchronization, and a reference signal from a system one generation ago may be used for data decoding. Similarly, the present technology does not need to be applied to differences in RAT between previous and previous generations. That is, it may generally be applied with different RATs.

Although it has been described above that the future system applies the signals and/or channels of the past system, conversely, the past system may apply the signals and/or channels of the future system.

"Data" in the above embodiments may indicate PDSCH, PDCCH, or PBCH. Additionally, "data" may indicate uplink signals and/or channels.

The embodiments described above can be combined with each other. The features shown in the embodiments described above can be combined with each other in various combinations. Such combinations are not limited to the particular combinations disclosed.

According to the above embodiment, the terminal 20 can reduce the amount of signals related to NR synchronization by performing NR synchronization using LTE signals.

That is, in a wireless communication system, it is possible to reduce overhead when a plurality of RATs (Radio Access Technologies) coexist on a single carrier.

(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 and terminal 20 include functionality to implement the embodiments described above. However, the base station 10 and the terminal 20 may each have only some of the functions in the embodiment.

<Base station 10>
FIG. 12 is a diagram showing an example of the functional configuration of base station 10 in the embodiment of the present invention. As shown in FIG. 12, 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. 12 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 unit 110 includes a function of generating a signal to be transmitted to the terminal 20 side and transmitting the signal wirelessly. The transmitting unit 110 also transmits network node-to-network messages to other network nodes. 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. Furthermore, the transmitter 110 has a function of transmitting NR-PSS, NR-SSS, NR-PBCH, DL/UL control signals, etc. to the terminal 20. Further, the receiving unit 120 receives messages between network nodes from other network nodes.

The setting unit 130 stores setting information set in advance and various setting information to be sent to the terminal 20. The content of the setting information is, for example, information related to DSS settings.

The control unit 140 performs control related to DSS settings, as described in the embodiment. Further, the control unit 140 controls communication using DSS. 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.

<Terminal 20>
FIG. 13 is a diagram showing an example of the functional configuration of the terminal 20 in the embodiment of the present invention. As shown in FIG. 13, 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. 13 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 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, etc. transmitted from the base station 10. For example, the transmitting unit 210 transmits a message to another terminal 20 using a PSCCH (Physical Sidelink Control Channel), a PSSCH (Physical Sidelink Shared Channel), a PSDCH (Physical Sidelink Discovery Channel), or a PSBCH (Physical Sidelink Broadcast Channel) as D2D communication. The receiving unit 220 receives PSCCH, PSSCH, PSDCH, PSBCH, etc. from other terminals 20 .

The setting unit 230 stores various types of setting information received from the base station 10 by the receiving unit 220. The setting unit 230 also stores setting information that is set in advance. The content of the setting information is, for example, information related to DSS settings.

The control unit 240 performs control related to DSS settings, as described in the embodiment. Further, the control unit 240 controls communication using DSS. A functional unit related to signal transmission in the control unit 240 may be included in the transmitting unit 210, and a functional unit related to signal reception in the control unit 240 may be included in the receiving unit 220.

(Hardware configuration)
The block diagrams (FIGS. 12 and 13) 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. 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. 14 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.

In addition, 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.

Further, 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 the programs. 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. 12 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. 13 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, for example, a network device, a network controller, a network card, a communication module, or the like. The communication device 1004 includes, for example, a high frequency switch, a duplexer, a filter, a frequency synthesizer, etc. to realize at least one of frequency division duplex (FDD) and time division duplex (TDD). It may be composed of. For example, a transmitting/receiving antenna, an amplifier section, a transmitting/receiving section, a transmission path 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.

(Summary of embodiments)
As described above, according to the embodiment of the present invention, there is provided a receiving section that receives a first signal of a first RAT (Radio Access Technology), a receiver that receives the first signal of the first RAT, and a receiver that receives the first signal of the first RAT (Radio Access Technology). A terminal is provided that includes a control unit that synchronizes with a cell of the second RAT using a QCL (Quasi-co-location) relationship with a second signal.

With the above configuration, the terminal 20 can reduce the amount of signals related to NR synchronization by performing NR synchronization using LTE signals. That is, in a wireless communication system, it is possible to reduce overhead when a plurality of RATs (Radio Access Technologies) coexist on a single carrier.

The second RAT may be transmitted on the same carrier as the first RAT. The terminal 20 can reduce the amount of signals related to NR synchronization by synchronizing NRs of the same carrier using LTE signals.

The QCL relationship may be such that the first signal is a QCL source and the second signal is a QCL destination. With this configuration, the terminal 20 can reduce the amount of signals related to NR synchronization by performing NR synchronization using LTE signals.

The control unit may assume that the first signal and the second signal, which have similar uses, are QCL. With this configuration, the terminal 20 can reduce the amount of signals related to NR synchronization by performing NR synchronization using LTE signals.

Further, according to an embodiment of the present invention, a reception procedure for receiving a first signal of a first RAT (Radio Access Technology), and a reception procedure for receiving a first signal of a first RAT (Radio Access Technology); A communication method is provided in which a terminal executes a control procedure for synchronizing with a cell of the second RAT using a QCL (Quasi-co-location) relationship.

With the above configuration, the terminal 20 can reduce the amount of signals related to NR synchronization by performing NR synchronization using LTE signals. That is, in a wireless communication system, it is possible to reduce overhead when a plurality of RATs (Radio Access Technologies) coexist on a single carrier.

(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.

Further, 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 include 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, It may be implemented by broadcast information (MIB (Master Information Block), SIB (System Information Block)), other signals, or a combination thereof. RRC signaling may also be called an RRC message, for example, RRC It may be a connection setup (RRC Connection Setup) message, an RRC connection reconfiguration (RRC Connection Reconfiguration) message, or the like.

Each aspect/embodiment described in this disclosure applies to LTE (Long Term Evolution), LTE-A (LTE-Advanced), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication system), and 5G (5th generation mobile communication system). 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), and systems that utilize and are extended based on these. It may be applied to at least one next generation system. 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 may 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 (eg, 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 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 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 described 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 device," "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)). The term "cell" or "sector" refers to a part or all of the coverage area of a base station and/or base station subsystem that provides communication services in this coverage. refers to

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, or the like. 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.

Furthermore, 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 by 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 read as "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 also 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.

Numerology may be a communication parameter applied to the transmission and/or reception of a 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 minislots. 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 for 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 minislot may be called a TTI. You can. 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 a normal TTI may be referred to as an abbreviated TTI, short TTI, partial or fractional TTI, shortened subframe, short subframe, minislot, subslot, slot, or the like.

Note that long TTI (for example, normal TTI, subframe, etc.) may be read as TTI with a time length exceeding 1 ms, and short TTI (for example, short TTI, etc.) It may also be read as a TTI having the above TTI length.

A resource block (RB) is a resource allocation unit in a time domain and a 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 long. 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.

Further, 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 within one carrier for a UE.

At least one of the configured BWPs may be active and the UE may not expect to transmit or receive a given signal/channel outside of 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 within 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 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, may be used 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 to 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

Claims (5)

a receiving unit that receives a first signal of a first RAT (Radio Access Technology);
a control unit that synchronizes with a cell of the second RAT using a QCL (Quasi-co-location) relationship between the first signal and a second signal of the second RAT ;
The receiving unit is a terminal that uses a third signal of a third RAT for data decoding in the second RAT . The terminal according to claim 1, wherein the second RAT is transmitted on the same carrier as the first RAT. The terminal according to claim 1, wherein the QCL relationship is such that the first signal is a QCL source and the second signal is a QCL destination. The terminal according to claim 1, wherein the control unit assumes that the first signal and the second signal, which have similar uses, are QCL. a reception procedure for receiving a first signal of a first RAT (Radio Access Technology);
A control procedure for synchronizing with a cell of the second RAT using a QCL (Quasi-co-location) relationship between the first signal and a second signal of the second RAT ;
A communication method in which a terminal executes a procedure of using a third signal of a third RAT for data decoding in the second RAT .

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