WO2019244217A1 - User terminal and wireless base station - Google Patents

Abstract

In order to communicate using an downlink control channel configuration suitable for communication requirements, this user terminal comprises: a receiver for receiving a demodulation reference signal having a single carrier waveform or a waveform to which transform precoding has been applied, and downlink control information comprising the single carrier waveform or the waveform to which transform precoding has been applied; and a controller for demodulating the downlink control information obtained by performing time-division multiplexing on the demodulation reference signal on the basis of the demodulation reference signal.

Description

User terminal and wireless base station

The present disclosure relates to a user terminal and a radio base station in a next-generation mobile communication system.

In a UMTS (Universal Mobile Telecommunications System) network, long term evolution (LTE: Long Term Evolution) has been specified for the purpose of higher data rates and lower delays (Non-Patent Document 1). Also, LTE-A (LTE Advanced, LTE @ Rel. 10, 11, 12, 13) has been specified for the purpose of further increasing the capacity and sophistication of LTE (LTE @ Rel. 8, 9).

Succession system of LTE (for example, FRA (Future Radio Access), 5G (5th generation mobile communication system), 5G + (plus), NR (New Radio), NX (New radio access), FX (Future generation radio access), LTE Rel. 14 or 15).

The base station controls data allocation (scheduling) to user terminals (UE: User Equipment). The base station notifies the UE of downlink control information (DCI: Downlink Control Information) indicating a data scheduling instruction using a downlink control channel (for example, PDCCH (Physical Downlink Control Channel)).

3GPP TS 36.300 V8.12.0 “Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 (Release 8), April 2010

In future wireless communication systems (for example, NR), support for various frequency bands and communication requirements is being studied.

場合 When using the existing downlink control channel configuration, the downlink control channel configuration may not be suitable for the communication requirements. In this case, there is a possibility that a decrease in system performance may occur.

Therefore, an object of the present disclosure is to provide a user terminal and a radio base station that perform communication using a downlink control channel configuration suitable for communication requirements.

The user terminal according to an aspect of the present disclosure, a demodulation reference signal having a waveform or a single carrier waveform to which conversion precoding is applied, and downlink control information having a waveform or a single carrier waveform to which conversion precoding is applied. And a control unit for demodulating the downlink control information time-division multiplexed with the demodulation reference signal based on the demodulation reference signal.

According to an embodiment of the present disclosure, communication can be performed using a configuration of a downlink control channel suitable for communication requirements.

1A to 1D are diagrams illustrating an example of DMRS and DCI mapping according to example 1. FIG. FIG. 2 is a diagram illustrating an example of mapping of PDCCH candidates according to example 2. 3A to 3C are diagrams illustrating an example of mapping of a PDCCH candidate having a higher AL according to example 3. FIG. FIG. 1 is a diagram illustrating an example of a schematic configuration of a wireless communication system according to an embodiment. It is a figure showing an example of the whole radio base station composition concerning one embodiment. FIG. 2 is a diagram illustrating an example of a functional configuration of a wireless base station according to one embodiment. It is a figure showing an example of the whole user terminal composition concerning one embodiment. It is a figure showing an example of functional composition of a user terminal concerning one embodiment. FIG. 2 is a diagram illustrating an example of a hardware configuration of a wireless base station and a user terminal according to an embodiment.

In a future wireless communication system (for example, at least one of NR, 5G, and 5G +; hereinafter, also simply referred to as NR), a downlink control channel for transmitting downlink control information (DCI: Downlink Control Information) has been studied. I have.

The UE monitors one or a plurality of control resource sets (CORESET: control resource set) set in its own terminal (may be referred to as blind decoding or blind detection) and detects downlink control information.

The DCI that schedules the reception of DL data (eg, a physical downlink (PDSCH)) and / or the measurement of a DL reference signal may be referred to as a DL assignment, a DL grant, a DL DCI, or the like. A DCI that schedules transmission of UL data (eg, PUSCH (Physical Uplink Shared Channel)) and / or transmission of an UL sounding (for measurement) signal may be referred to as UL grant, UL @ DCI, or the like.

セ ッ ト The set of PDCCH candidates to be monitored is also called a search space. The radio base station allocates DCI to a predetermined PDCCH candidate included in the search space. The UE performs blind decoding on one or more candidate resources in the search space and detects DCI for the UE. The search space may be set by upper layer signaling common to users, or may be set by upper layer signaling specific to each user. Further, two or more search spaces may be set for the user terminal on the same carrier.

In the existing LTE, a plurality of types of aggregation levels (AL: Aggregation Level) are defined in the search space for the purpose of link adaptation. The AL corresponds to the number of resource units (radio resources having a predetermined time length and a predetermined bandwidth, for example, a control channel element (CCE) or an extended control channel element (ECCE)) constituting DCI. Also, the search space has a plurality of PDCCH candidates for a certain AL. The maximum number of PDCCH candidates may be defined for each AL.

The DCI is attached with a cyclic redundancy check (CRC) bit. The CRC is masked (scrambled) by a UE-specific identifier (eg, a cell-radio network temporary identifier (C-RNTI: Cell-Radio Network Temporary Identifier)) or a system-wide identifier. The UE can detect the DCI in which the CRC is scrambled by the C-RNTI corresponding to the own terminal and the DCI in which the CRC is scrambled by the system common identifier.

A parameter indicating a monitoring configuration (configuration, monitoring opportunity) of the PDCCH candidate may be set in the UE. The monitoring configuration includes at least a monitoring period. A parameter indicating the coreset configuration may be set in the UE. A parameter indicating one or more partial bands (bandwidth part, BWP: Bandwidth @ part) configuration for each component carrier (CC: Component @ Carrier) may be set in the UE.

Hereinafter, upper layer signaling includes, for example, RRC (Radio Resource Control) signaling, MAC (Medium Access Control) signaling (eg, MAC control element (MAC CE (Control Element)), MAC PDU (Protocol Data Unit)), and broadcast information (Master information block (MIB: Master @ Information @ Block), system information block (SIB: System @ Information @ Block)), or a combination thereof. Further, the physical layer signaling may be, for example, DCI.

A sub-carrier interval (Sub-Carrier @ Spacing: SCS, for example, SCS for CORRESET) used for the $ PDCCH may be set in the UE. The parameter for determining the SCS may be notified to the UE by higher layer signaling, or may be implicitly notified to the UE by another parameter. The SCS associated with the frequency may be configured on the UE.

In NR, the UE uses at least one frequency band (carrier frequency, frequency band, operation band) of a first frequency band (FR1: Frequency @ Range @ 1) and a second frequency band (FR2: Frequency @ Range @ 2). Communication (transmission and reception of signals, measurement, etc.) is being studied.

{For example, FR1 may be a frequency band of 6 GHz or less (sub-6 GHz (sub-6 GHz)), and FR2 may be a frequency band higher than 24 GHz (above-24 GHz). The frequency bands and definitions of FR1 and FR2 are not limited to these, and for example, FR1 may be a higher frequency band than FR2.

FR2 may be used only for a time division duplex (TDD) band. FR2 may be referred to as an mmW band because it corresponds to a millimeter wave (mmW: millimeter @ Wave) having a wavelength of about 1 mm to 10 mm. The mmW band may be called EHF (Extremely High Frequency).

Note that FR1 and FR2 of the present disclosure are replaced with a first frequency range (first frequency range) and a second frequency range (second frequency range), which are more general expressions that are not limited to specific frequency bands, respectively. You may be. Further, FR1 and FR2 of the present disclosure may be read in a frequency range lower than a predetermined frequency (low frequency range) and a frequency range higher than the predetermined frequency (high frequency range), respectively. The predetermined frequency may be 30 GHz, 40 GHz, 50 GHz, 60 GHz, or the like.

ＳＣThe SCS required in FR2 may be higher (wider) than the SCS required in FR1. FR1 may be defined as a frequency range in which at least one of 15, 30, and 60 kHz is used as SCS. FR2 may be defined as a frequency range in which at least one of 60 and 120 kHz is used as SCS.

It is considered that the peak-to-average power ratio (PAeak to average power ratio) required in FR2 is lower than the PAPR required in FR1.

The electric wave of FR2 has less diffraction than the electric wave of FR1. Thus, the radio wave of FR2 may be more easily blocked (shielded) than the radio wave of FR1.

The coverage when using FR2 is smaller than the coverage when using FR1. Thus, it is conceivable that the number of UEs in the coverage of FR2 becomes smaller than the number of UEs in the coverage of FR1.

ＦＲ In FR2, analog beamforming (BF) may be used in order to cope with radio wave blocking and reduction of coverage.

As described above, since the communication requirements and characteristics in the second frequency range higher than the predetermined frequency are different from the communication requirements and characteristics in the first frequency range lower than the predetermined frequency, the downlink control channel (PDCCH) for the first frequency range is different. It is possible that the configuration (structure) is not suitable for the second frequency range. If a PDCCH configuration suitable for a frequency is not used, system performance may be degraded. Therefore, the present inventors studied a PDCCH configuration suitable for a frequency, and reached the present invention.

Also, the present inventors have conceived of a PDCCH configuration for the second frequency range. For example, in the PDCCH configuration for the second frequency range, the DMRS (Demodulation Reference Signal) and DCI have a DFT (Discrete Fourier Transform) -s (spread) -OFDM (Orthogonal Frequency Division Multiplexing) waveform or a single carrier waveform. You may. In the PDCCH configuration for the second frequency range, DCI may be time division multiplexed (TDM) to DMRS.

Hereinafter, embodiments according to the present disclosure will be described in detail with reference to the drawings. The wireless communication method according to each embodiment may be applied alone or in combination.

In the following description, a DMRS mapped to a resource allocated to the PDCCH (PDCCH @ DMRS, DMRS for DCI demodulation) may be simply referred to as DMRS.

態 様 The following aspects 1 to 3 describe the PDCCH configuration. Aspects 4 and 5 describe a method of setting a PDCCH configuration.

(Aspect 1)
In aspect 1, the PDCCH may be based on a DFT-s-OFDM waveform or a single carrier waveform.

In the DFT-s-OFDM waveform, DFT precoding (transform precoding, transform 、 precoding) is applied to modulation symbols (complex value modulation symbols, sequences), IFFT (Inverse Fast Fourier Transform) is applied to the result, and the result is May be a waveform obtained by adding a cyclic prefix (Cyclic @ Prefix: CP) to the data.

The single carrier waveform may be a waveform obtained by applying DFT and IFFT to modulation symbols (complex value modulation symbols and sequences) and adding CP or Guard {period} (GP).

DMRS may have a DFT-s-OFDM waveform or a single carrier waveform. DCI (signal obtained by modulation and mapping of DCI) in PDCCH may have a DFT-s-OFDM waveform or a single carrier waveform.

DFT-s-OFDM waveform or single carrier waveform can suppress PAPR as compared with CP (Cyclic Prefix) -OFDM waveform (multicarrier waveform).

The DMRS may use a low PAPR sequence (low-PAPR sequence) such as a Zadoff-Chu (ZC) sequence or a computer-generated (CG) sequence. When the DMRS sequence length is equal to or greater than a predetermined value (for example, 36), the ZC sequence is used as the DMRS, and when the DMRS sequence length is shorter than the predetermined sequence length, a predefined CG sequence is used as the DMRS. You may.

DMRS may be a wideband RS or a narrowband RS. The wideband RS may be a sequence mapped to all consecutive frequency resources in a band (for example, CORESET) that can be allocated to a PDCCH candidate. The narrowband RS may be a sequence mapped to at least one part in a band that can be allocated to a PDCCH candidate. At least one part may be set as a unit (granularity) using a resource element (RE), a resource element group (REG), a REG bundle, a resource block (RB), and the like. The parameter indicating whether the DMRS is a wideband RS or a narrowband RS may be referred to as a DMRS mapping type, a DMRS type, or the like. The UE may determine whether the broadband RS or the narrowband RS is based on precoderGranularity included in RRC @ IE (Information @ Element) of RESET being sameAsREG-bundle or allContiguousRBs. In this case, precoderGranularity = sameAsREG-bundle (REG bundle) corresponds to a narrowband RS, and precoderGranularity = allContiguousRBs (all consecutive RBs in CORESET) corresponds to a wideband RS.

The DCI transmitted on the PDCCH may be time division multiplexed (Time Division Multiplexing (TDM)) with the PDCCH DMRS. By performing DCI with DMRS and TDM, PAPR can be suppressed as compared with a case where DCI is frequency-division multiplexed with DMRS.

DCI may be mapped to continuous frequency resources (eg, resource elements (REs), subcarriers) (consecutive or contiguous mapping, local mapping). DCI may be mapped to equally spaced frequency resources (eg, resource elements (REs), subcarriers) (equally spaced mapping, non-continuous mapping, distributed mapping).

Consecutive mapping may be similar to frequency domain resource allocation in UL (PDSCH) (eg, UL resource allocation type 1). For example, the UE may set a start frequency resource (for example, start RB) and a bandwidth (for example, the number of RBs) for a frequency resource to be allocated to DCI.

The continuous mapping of DCI may follow one of the following aspects 1-1 and 1-2.

<Aspect 1-1>
As shown in FIG. 1A, the DMRS is a narrowband RS, and continuous mapping may be applied to DCI. DMRS may be mapped to the same frequency resource as DCI. DMRS may be mapped to an OFDM symbol before DCI.

<Aspect 1-2>
As shown in FIG. 1B, the DMRS is a wideband RS, and continuous mapping may be applied to DCI. DCI may be mapped to part of the DMRS band. The bandwidth to which DCI is mapped may be smaller than the bandwidth to which DMRS is mapped.

Equidistant mapping of DCI may follow one of the following aspects 1-3 and 1-4.

<Aspect 1-3>
As shown in FIG. 1C, the equally-spaced mapping may be applied to the DMRS, and the equally-spaced mapping may be applied to the DCI. Both DMRS and DCI may be mapped to distributed frequency resources. The DMRS in each of the plurality of frequency resources may be a narrowband RS. The DCI may be mapped to some or all of the DMRS band.

<Aspect 1-4>
As shown in FIG. 1D, the DMRS may be a wideband RS, and the DCI may be applied with equal-space mapping. DCI may be mapped to a plurality of distributed frequency resources within the band of DMRS.

Any of the above aspects 1-1 to 1-4 may be referred to as a type (mapping type, allocation type).

The DMRS may be mapped to a time resource before DCI (eg, a symbol) or may be mapped to a time resource after DCI. The DMRS time resource and the DCI time resource may be continuous or discontinuous.

According to mode 1, since the PDCCH has a single carrier waveform, PAPR of the PDCCH can be suppressed. Further, the DCI on the PDCCH is subjected to TDM by the DMRS, so that the PAPR of the PDCCH can be suppressed.

(Aspect 2)
In aspect 2, in PDCCH monitoring, the UE may monitor nested (nested) PDCCH candidates.

A PDCCH candidate having a lower aggregation level (AL, CCE (control channel element) aggregation level) may overlap a PDCCH candidate having a higher AL (AL higher than the lower AL). The frequency resource of the PDCCH candidate having the lower AL may be included in the frequency resource of the PDCCH candidate having the higher AL.

The UE may perform channel estimation by regarding a plurality of PDCCH candidates having a lower AL as one PDCCH candidate having a higher AL than the PDCCH candidates. Further, the UE may perform channel estimation by regarding one PDCCH candidate having a higher AL as a plurality of PDCCH candidates having a lower AL than the PDCCH candidate.

同 様 Similarly to example 1, DCI and DMRS may be TDM-executed in each PDCCH candidate. The UE may reuse the channel estimation result based on the DMRS in a plurality of overlapping PDCCH candidates.

よ う As shown in FIG. 2, two PDCCH candidates with AL = 1 may overlap with one PDCCH candidate with AL = 2. The UE performs blind decoding of each of the three set PDCCH candidates. On the other hand, the UE can reduce the number of times of channel estimation by reusing channel estimation results of overlapping bands between PDCCH candidates having different ALs. For example, the UE may reuse the channel estimation result based on the DMRS for two PDCCH candidates with an AL of 1 for demodulation of one PDCCH candidate with an AL of 2. For example, the UE may reuse the channel estimation result based on the DMRS for one PDCCH candidate with AL = 2 for demodulation of two PDCCH candidates with AL = 1.

According to the above aspect 2, the UE can reduce the load of channel estimation in monitoring PDCCH candidates.

(Aspect 3)
In aspect 3, PDCCH candidates with an AL higher than the predetermined AL may be mapped to time / frequency resources according to a particular mapping method. The upper AL may be realized according to one of the following aspects 3-1 to 3-2.

<Aspect 3-1>
In the frequency domain, more resources may be allocated to PDCCH candidates with higher ALs than resources allocated to PDCCH candidates with lower ALs. In other words, as the AL of the PDCCH candidate increases, the resources allocated to the PDCCH candidate in the frequency domain increase. For example, the size of the frequency resource (for example, the number of REs) allocated to the PDCCH candidate may be proportional to the AL of the PDCCH candidate.

For example, if a PDCCH candidate with an AL of 2 is mapped over 2 CCEs, a PDCCH candidate with an AL of 4 may be mapped over 4 CCEs as shown in FIG. 3A. In this PDCCH candidate, DMRS may be mapped over 4 CCEs and 1 OFDM symbol, and DCI may be mapped over 4 CCEs and 1 OFDM symbol.

{Circle around (3)} According to aspect 3-1, it is possible to increase the size of DCI while maintaining the accuracy of channel estimation.

<Aspect 3-2>
The time resources allocated to the PDCCH candidate having the higher AL may be more than the time domain resources allocated to the PDCCH candidates having the lower AL than the PDCCH candidate. In other words, the time resources allocated to the PDCCH candidates increase with the increase in the AL of the PDCCH candidates.

Especially, as the AL of the PDCCH candidate increases, the time resource allocated to DCI may increase. For example, the size (for example, the number of symbols) of the time resources allocated to DCI may be proportional to the AL of the PDCCH candidate.

The DMRS for a PDCCH candidate having a higher AL may be the same as the DMRS for a PDCCH candidate having a lower AL than the PDCCH candidate. The bandwidth of the DMRS may be the same as the bandwidth of the PDCCH candidate.

The precoder granularity may be the size of a PDCCH candidate. The precoder granularity indicates the size of consecutive resources to which the same precoding is applied. The continuous resources may be only in the frequency direction or may include the time direction. The precoder granularity may be included in an upper layer parameter (for example, a ControlResourceSet information element) for setting the CORESET. The precoder granularity may indicate a REG bundle size, a CORESET size in a frequency domain, and the like.

For example, as shown in FIG. 3B, in a PDCCH candidate with AL of 4, DMRS may be mapped over 2 CCEs and 1 OFDM symbol, and DCI may be mapped over 2 CCEs and 2 OFDM symbols.

According to aspect 3-2, PAPR can be reduced by narrowing the band of PDCCH candidates as compared to aspect 3-1.

<Aspect 3-3>
The time resources allocated to the PDCCH candidate having the higher AL may be more than the time domain resources allocated to the PDCCH candidates having the lower AL than the PDCCH candidate. In other words, the time resources allocated to the PDCCH candidates increase with the increase in the AL of the PDCCH candidates.

In particular, as the AL of the PDCCH candidate increases, both the time resources (eg, the number of symbols) assigned to the DMRS and the time resources (eg, the number of symbols) assigned to the DCI in the time domain increase. Is also good. For example, both the size of the time resource allocated to the DMRS and the size of the time resource allocated to the DCI may be proportional to the AL of the PDCCH candidate.

The precoder granularity may be the size of a PDCCH candidate or the size of a set of DMRS and DCI over two or more consecutive OFDM symbols.

For example, as shown in FIG. 3C, in a PDCCH candidate with AL of 4, the first DMRS is mapped over one OFDM symbol and two CCEs, the first half of DCI is mapped to the same two CCEs of the next one OFDM symbol, and The second DMRS may be mapped to the same 2CCE of one OFDM symbol, and the latter half of DCI may be mapped to the same 2CCE of the next 1OFDM symbol.

The UE may demodulate the first half of DCI using the channel estimation result based on the first DMRS, and may demodulate the second half of DCI using the channel estimation result based on the second DMRS. Alternatively, the UE may average channel estimation results based on the first DMRS and the second DMRS, assuming that the same precoding is applied to all of the first to fourth OFDM symbols. Further, the UE demodulates the first half of DCI using the channel estimation result based on the first DMRS and performs the operation of demodulating the second half of DCI using the channel estimation result based on the second DMRS, or performs the first operation. Whether to perform an operation of averaging the channel estimation result based on the DMRS and the second DMRS may be set by higher layer signaling such as RRC.

{Circle around (3)} According to the aspect 3-3, it is possible to reduce the PAPR and to improve the demodulation performance in an environment where channel fluctuations are faster than the aspect 3-2.

(Aspect 4)
In aspect 4, the UE may be configured with a PDCCH configuration by higher layer signaling.

The UE may be configured with at least one of a plurality of PDCCH configurations by explicit notification in an upper layer. The plurality of PDCCH configurations may include a first PDCCH configuration to which at least one of aspects 1 to 3 is applied, and a second PDCCH configuration according to an existing specification (for example, Rel. 15).

Between the first PDCCH configuration and the second PDCCH configuration, a waveform (for example, whether or not a multi-carrier (CP-OFDM) waveform), a precoding granularity (precoder granularity), a coding scheme, a CRC length, a monitoring period, a frequency At least one of the resource granularity, the range of the time length, the range of the aggregation level, and the multiplexing method of DMRS and DCI may be different.

に お い て In the second PDCCH configuration, DMRS and DCI may have a CP-OFDM waveform. In the second PDCCH configuration, DCI may be frequency division multiplexed (FDM) with DMRS. In the second PDCCH configuration, the time length of the PDCCH candidate may be set to 1 to 3 OFDM symbols. In the second PDCCH configuration, the granularity of frequency resource allocation may be 6 RBs.

The UE may be configured with a PDCCH configuration for each search space configuration. The UE may be configured with a PDCCH configuration for each CORESET configuration. The UE may be configured with a PDCCH configuration for each BWP configuration. The UE may be configured with a PDCCH configuration for each CC (Component @ Carrier) configuration.

The UE may assume that the first PDCCH configuration and the second PDCCH configuration are not configured at the same time in a given serving cell or in a given DL BWP of one serving cell (the first PDCCH configuration and the second PDCCH configuration are configured at the same time). You don't have to expect that).

According to the above-described aspect 4, an appropriate PDCCH configuration for a given frequency can be set in the UE.

(Aspect 5)
In aspect 5, the UE may be configured with a PDCCH configuration without using explicit notification in an upper layer.

The UE may be configured with one of a plurality of PDCCH configurations by implicit notification or explicit notification in a lower layer. The plurality of PDCCH configurations may include the above-described first PDCCH configuration and second PDCCH configuration.

The UE may determine the PDCCH configuration based on at least one of the following aspects 5-1, 5-2, and 5-3.

<Aspect 5-1>
The UE may determine the PDCCH configuration based on the frequency band. The UE may assume that the PDCCH candidates in the first frequency band follow the first PDCCH configuration. A UE connected in the first frequency band may monitor a PDCCH candidate according to the first PDCCH configuration. The first frequency band may be a frequency band higher than a predetermined frequency (for example, 24 GHz, 6 GHz, or the like).

A plurality of PDCCH configurations may be respectively associated with a plurality of frequency bands. The UE may assume that PDCCH candidates in the second frequency band follow the second PDCCH configuration. The second frequency band may be a frequency band lower than the predetermined frequency.

<Aspect 5-2>
The UE may determine the PDCCH configuration based on a synchronization signal (Synchronization Signal).

A plurality of PDCCH configurations may be associated with a plurality of synchronization signal configurations, respectively. A plurality of synchronization signal configurations may be associated with a plurality of frequency bands, respectively. The UE may blind detect a plurality of synchronization signal configurations and recognize a PDCCH configuration associated with the detected synchronization signal configurations. The UE that has detected the synchronization signal having the first synchronization signal configuration may monitor the PDCCH candidates according to the first PDCCH configuration associated with the first synchronization signal configuration.

<Aspect 5-3>
The UE may determine a PDCCH configuration based on a physical broadcast channel (PBCH).

PBCH may include information (field) indicating PDCCH configuration. The UE may receive the PBCH and recognize the PDCCH configuration of a given carrier based on the field.

A plurality of PDCCH configurations may be associated with a plurality of PBCH configurations (PBCH configuration, SS (Synchronization Signal) / PBCH block configuration). Multiple PBCH configurations may be associated with multiple frequency bands, respectively. The UE may blindly detect the PBCH configuration and recognize a PDCCH configuration corresponding to the detected PBCH configuration. The UE that has detected the synchronization signal having the first PBCH configuration may monitor PDCCH candidates according to the first PDCCH configuration associated with the first PBCH configuration.

According to the above-described aspect 5, it is possible to set an appropriate PDCCH configuration for a given frequency in the UE while suppressing overhead of higher layer signaling.

(Wireless communication system)
Hereinafter, the configuration of the wireless communication system according to an embodiment of the present disclosure will be described. In this wireless communication system, communication is performed using any of the wireless communication methods according to the above embodiments of the present disclosure or a combination thereof.

FIG. 4 is a diagram illustrating an example of a schematic configuration of a wireless communication system according to an embodiment. In the wireless communication system 1, carrier aggregation (CA) and / or dual connectivity (DC) in which a plurality of basic frequency blocks (component carriers) each having a system bandwidth (for example, 20 MHz) of the LTE system as one unit are applied. can do.

The wireless communication system 1 includes LTE (Long Term Evolution), LTE-A (LTE-Advanced), LTE-B (LTE-Beyond), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication system), and 5G. (5th generation mobile communication system), NR (New Radio), FRA (Future Radio Access), New-RAT (Radio Access Technology), etc., or a system for realizing these.

The radio communication system 1 includes a radio base station 11 forming a macro cell C1 having a relatively wide coverage, and a radio base station 12 (12a-12c) arranged in the macro cell C1 and forming a small cell C2 smaller than the macro cell C1. , Is provided. Further, user terminals 20 are arranged in the macro cell C1 and each small cell C2. The arrangement, number, and the like of each cell and the user terminals 20 are not limited to the modes shown in the figure.

The user terminal 20 can be connected to both the radio base station 11 and the radio base station 12. It is assumed that the user terminal 20 uses the macro cell C1 and the small cell C2 simultaneously using CA or DC. In addition, the user terminal 20 may apply CA or DC using a plurality of cells (CCs) (for example, five or less CCs, six or more CCs).

Communication between the user terminal 20 and the radio base station 11 can be performed using a carrier having a relatively low frequency band (for example, 2 GHz) and a narrow bandwidth (also referred to as an existing carrier or a legacy carrier). On the other hand, a carrier having a relatively high frequency band (for example, 3.5 GHz, 5 GHz or the like) and a wide bandwidth may be used between the user terminal 20 and the radio base station 12, The same carrier as that between may be used. The configuration of the frequency band used by each wireless base station is not limited to this.

The user terminal 20 can perform communication using time division duplex (TDD: Time Division Duplex) and / or frequency division duplex (FDD: Frequency Division Duplex) in each cell. In each cell (carrier), a single numerology may be applied, or a plurality of different numerologies may be applied.

Numerology may be a communication parameter applied to transmission and / or reception of a certain signal and / or channel, for example, subcarrier interval, bandwidth, symbol length, cyclic prefix length, subframe length. , TTI length, number of symbols per TTI, radio frame configuration, specific filtering processing performed by the transceiver in the frequency domain, specific windowing processing performed by the transceiver in the time domain, and the like. For example, for a certain physical channel, if the subcarrier intervals of the constituent OFDM symbols are different and / or if the number of OFDM symbols is different, the numerology may be referred to as different.

The wireless base station 11 and the wireless base station 12 (or between the two wireless base stations 12) are connected by wire (for example, an optical fiber compliant with CPRI (Common Public Radio Interface), an X2 interface, or the like) or wirelessly. May be done.

The wireless base station 11 and each wireless base station 12 are connected to the upper station device 30 and connected to the core network 40 via the upper station device 30. Note that the higher station apparatus 30 includes, for example, an access gateway apparatus, a radio network controller (RNC), and a mobility management entity (MME), but is not limited thereto. Further, each wireless base station 12 may be connected to the higher station apparatus 30 via the wireless base station 11.

The radio base station 11 is a radio base station having relatively wide coverage, and may be called a macro base station, an aggregation node, an eNB (eNodeB), a transmission / reception point, or the like. The wireless base station 12 is a wireless base station having local coverage, and includes a small base station, a micro base station, a pico base station, a femto base station, a HeNB (Home eNodeB), an RRH (Remote Radio Head), and transmission / reception. It may be called a point or the like. Hereinafter, when the wireless base stations 11 and 12 are not distinguished, they are collectively referred to as a wireless base station 10.

Each user terminal 20 is a terminal corresponding to various communication systems such as LTE and LTE-A, and may include not only mobile communication terminals (mobile stations) but also fixed communication terminals (fixed stations).

In the wireless communication system 1, Orthogonal Frequency Division Multiple Access (OFDMA) is applied to the downlink as a wireless access method, and Single Carrier-Frequency Division Multiple Access (SC-FDMA: Single Carrier) is applied to the uplink. Frequency Division Multiple Access) and / or OFDMA is applied.

OFDMA is a multicarrier transmission scheme in which a frequency band is divided into a plurality of narrow frequency bands (subcarriers), and data is mapped to each subcarrier to perform communication. The SC-FDMA divides a system bandwidth into bands constituted by one or continuous resource blocks for each terminal, and a single carrier transmission that reduces interference between terminals by using different bands for a plurality of terminals. It is a method. The uplink and downlink radio access schemes are not limited to these combinations, and other radio access schemes may be used.

In the wireless communication system 1, as downlink channels, a downlink shared channel (PDSCH: Physical Downlink Shared Channel), a broadcast channel (PBCH: Physical Broadcast Channel), a downlink L1 / L2 control channel, and the like shared by each user terminal 20 are used. Used. The PDSCH transmits user data, upper layer control information, SIB (System Information Block), and the like. Also, MIB (Master \ Information \ Block) is transmitted by PBCH.

Downlink L1 / L2 control channels include PDCCH (Physical Downlink Control Channel), EPDCCH (Enhanced Physical Downlink Control Channel), PCFICH (Physical Control Format Indicator Channel), PHICH (Physical Hybrid-ARQ Indicator Channel), and the like. Downlink control information (DCI: Downlink Control Information) including PDSCH and / or PUSCH scheduling information is transmitted by the PDCCH.

ス ケ ジ ュ ー リ ン グ The scheduling information may be notified by DCI. For example, a DCI that schedules DL data reception may be called a DL assignment, and a DCI that schedules UL data transmission may be called an UL grant.

PCFICH transmits the number of OFDM symbols used for PDCCH. The PHICH transmits acknowledgment information (eg, retransmission control information, HARQ-ACK, ACK / NACK, etc.) of HARQ (Hybrid Automatic Repeat Repeat reQuest) to the PUSCH. The EPDCCH is frequency-division multiplexed with a PDSCH (Downlink Shared Data Channel) and used for transmission of DCI and the like like the PDCCH.

In the wireless communication system 1, as an uplink channel, an uplink shared channel (PUSCH: Physical Uplink Shared Channel), an uplink control channel (PUCCH: Physical Uplink Control Channel), a random access channel (PRACH: Physical Random Access Channel) or the like is used. By PUSCH, user data, higher layer control information, etc. are transmitted. Also, downlink radio quality information (CQI: Channel Quality Indicator), delivery confirmation information, scheduling request (SR: Scheduling Request), and the like are transmitted by PUCCH. The PRACH transmits a random access preamble for establishing a connection with a cell.

In the wireless communication system 1, as a downlink reference signal, a cell-specific reference signal (CRS: Cell-specific Reference Signal), a channel state information reference signal (CSI-RS: Channel State Information-Reference Signal), and a demodulation reference signal (DMRS: DeModulation Reference Signal, a position determination reference signal (PRS: Positioning Reference Signal), and the like are transmitted. In the wireless communication system 1, a measurement reference signal (SRS: Sounding Reference Signal), a demodulation reference signal (DMRS), and the like are transmitted as uplink reference signals. The DMRS may be called a user terminal specific reference signal (UE-specific Reference Signal). The transmitted reference signal is not limited to these.

(Wireless base station)
FIG. 5 is a diagram illustrating an example of the entire configuration of the wireless base station according to the embodiment. The wireless base station 10 includes a plurality of transmitting / receiving antennas 101, an amplifier unit 102, a transmitting / receiving unit 103, a baseband signal processing unit 104, a call processing unit 105, and a transmission path interface 106. The transmitting / receiving antenna 101, the amplifier unit 102, and the transmitting / receiving unit 103 may be configured to include at least one each.

(4) User data transmitted from the radio base station 10 to the user terminal 20 via downlink is input from the higher station apparatus 30 to the baseband signal processing unit 104 via the transmission path interface 106.

In the baseband signal processing unit 104, regarding user data, processing of a PDCP (Packet Data Convergence Protocol) layer, division / combination of user data, transmission processing of an RLC layer such as RLC (Radio Link Control) retransmission control, and MAC (Medium Access) Control) The transmission / reception unit performs retransmission control (for example, HARQ transmission processing), scheduling, transmission format selection, channel coding, inverse fast Fourier transform (IFFT) processing, precoding processing, and so on. 103. The downlink control signal is also subjected to transmission processing such as channel coding and inverse fast Fourier transform, and transferred to the transmission / reception unit 103.

The transmission / reception section 103 converts the baseband signal precoded and output from the baseband signal processing section 104 for each antenna into a radio frequency band, and transmits the radio frequency band. The radio frequency signal frequency-converted by the transmitting / receiving section 103 is amplified by the amplifier section 102 and transmitted from the transmitting / receiving antenna 101. The transmission / reception unit 103 can be configured from a transmitter / receiver, a transmission / reception circuit, or a transmission / reception device described based on common recognition in the technical field according to the present disclosure. Note that the transmission / reception unit 103 may be configured as an integrated transmission / reception unit, or may be configured from a transmission unit and a reception unit.

On the other hand, as for an uplink signal, a radio frequency signal received by the transmission / reception antenna 101 is amplified by the amplifier unit 102. The transmitting / receiving section 103 receives the upstream signal amplified by the amplifier section 102. Transmitting / receiving section 103 frequency-converts the received signal into a baseband signal and outputs the baseband signal to baseband signal processing section 104.

The baseband signal processing unit 104 performs fast Fourier transform (FFT: Fast Fourier Transform), inverse discrete Fourier transform (IDFT), and error correction on user data included in the input uplink signal. Decoding, reception processing of MAC retransmission control, reception processing of the RLC layer and PDCP layer are performed, and the data is transferred to the upper station apparatus 30 via the transmission path interface 106. The call processing unit 105 performs call processing (setting, release, etc.) of a communication channel, state management of the wireless base station 10, management of wireless resources, and the like.

The transmission path interface 106 transmits and receives signals to and from the higher-level station device 30 via a predetermined interface. The transmission path interface 106 transmits and receives signals (backhaul signaling) to and from another wireless base station 10 via an interface between base stations (for example, an optical fiber compliant with CPRI (Common Public Radio Interface), an X2 interface). You may.

Further, the transmitting and receiving unit 103 transmits the demodulation reference signal having the waveform or the single carrier waveform to which the conversion precoding is applied, and the downlink control information having the waveform or the single carrier waveform to which the conversion precoding is applied. Is also good.

FIG. 6 is a diagram illustrating an example of a functional configuration of the wireless base station according to an embodiment of the present disclosure. In this example, functional blocks of characteristic portions in the present embodiment are mainly shown, and it may be assumed that the wireless base station 10 also has other functional blocks necessary for wireless communication.

The baseband signal processing unit 104 includes at least a control unit (scheduler) 301, a transmission signal generation unit 302, a mapping unit 303, a reception signal processing unit 304, and a measurement unit 305. Note that these configurations may be included in the radio base station 10, and some or all of the configurations need not be included in the baseband signal processing unit 104.

The control unit (scheduler) 301 controls the entire wireless base station 10. The control unit 301 can be configured from a controller, a control circuit, or a control device described based on common recognition in the technical field according to the present disclosure.

The control unit 301 controls, for example, signal generation in the transmission signal generation unit 302, signal assignment in the mapping unit 303, and the like. Further, the control unit 301 controls a signal reception process in the reception signal processing unit 304, a signal measurement in the measurement unit 305, and the like.

The control unit 301 performs scheduling (for example, resources) of system information, a downlink data signal (for example, a signal transmitted on the PDSCH), and a downlink control signal (for example, a signal transmitted on the PDCCH and / or the EPDCCH; acknowledgment information and the like). Allocation). Further, control section 301 controls generation of a downlink control signal, a downlink data signal, and the like based on a result of determining whether or not retransmission control is required for an uplink data signal.

The control unit 301 controls scheduling of a synchronization signal (for example, PSS (Primary Synchronization Signal) / SSS (Secondary Synchronization Signal)) and a downlink reference signal (for example, CRS, CSI-RS, DMRS).

The control unit 301 transmits an uplink data signal (for example, a signal transmitted on the PUSCH), an uplink control signal (for example, a signal transmitted on the PUCCH and / or PUSCH, acknowledgment information, etc.), a random access preamble (for example, a PRACH). (Transmission signal), scheduling of uplink reference signals and the like.

The control unit 301 may map the time-division multiplexed downlink control information to the demodulation reference signal used for demodulation of the downlink control information.

Transmission signal generation section 302 generates a downlink signal (downlink control signal, downlink data signal, downlink reference signal, etc.) based on an instruction from control section 301, and outputs the generated downlink signal to mapping section 303. The transmission signal generation unit 302 can be configured from a signal generator, a signal generation circuit, or a signal generation device described based on common recognition in the technical field according to the present disclosure.

The transmission signal generation unit 302 generates a DL assignment for notifying downlink data allocation information and / or a UL grant for notifying uplink data allocation information, based on an instruction from the control unit 301, for example. The DL assignment and the UL grant are both DCI and follow the DCI format. In addition, the downlink data signal is subjected to an encoding process and a modulation process according to an encoding rate, a modulation scheme, and the like determined based on channel state information (CSI: Channel \ State \ Information) from each user terminal 20 and the like.

Mapping section 303 maps the downlink signal generated by transmission signal generating section 302 to a predetermined radio resource based on an instruction from control section 301, and outputs it to transmitting / receiving section 103. The mapping unit 303 can be configured from a mapper, a mapping circuit, or a mapping device described based on common recognition in the technical field according to the present disclosure.

(4) The reception signal processing unit 304 performs reception processing (for example, demapping, demodulation, decoding, and the like) on the reception signal input from the transmission / reception unit 103. Here, the received signal is, for example, an uplink signal (uplink control signal, uplink data signal, uplink reference signal, etc.) transmitted from the user terminal 20. The reception signal processing unit 304 can be configured from a signal processor, a signal processing circuit, or a signal processing device described based on common recognition in the technical field according to the present disclosure.

(4) The reception signal processing unit 304 outputs the information decoded by the reception processing to the control unit 301. For example, when a PUCCH including HARQ-ACK is received, HARQ-ACK is output to control section 301. Further, the reception signal processing unit 304 outputs the reception signal and / or the signal after the reception processing to the measurement unit 305.

(4) The measurement unit 305 performs measurement on the received signal. The measurement unit 305 can be configured from a measurement device, a measurement circuit, or a measurement device described based on common recognition in the technical field according to the present disclosure.

For example, the measurement unit 305 may perform RRM (Radio Resource Management) measurement, CSI (Channel State Information) measurement, or the like based on the received signal. The measurement unit 305 receives the reception power (for example, RSRP (Reference Signal Received Power)), the reception quality (for example, RSRQ (Reference Signal Received Quality), SINR (Signal to Interference plus Noise Ratio), SNR (Signal to Noise Ratio)). , Signal strength (for example, RSSI (Received @ Signal @ Strength @ Indicator)), channel information (for example, CSI), and the like. The measurement result may be output to the control unit 301.

(User terminal)
FIG. 7 is a diagram illustrating an example of the overall configuration of the user terminal according to the embodiment. The user terminal 20 includes a plurality of transmitting / receiving antennas 201, an amplifier unit 202, a transmitting / receiving unit 203, a baseband signal processing unit 204, and an application unit 205. Note that the transmitting / receiving antenna 201, the amplifier unit 202, and the transmitting / receiving unit 203 may be configured to include at least one each.

(4) The radio frequency signal received by the transmitting / receiving antenna 201 is amplified by the amplifier unit 202. The transmission / reception unit 203 receives the downlink signal amplified by the amplifier unit 202. The transmitting / receiving section 203 converts the frequency of the received signal into a baseband signal and outputs the baseband signal to the baseband signal processing section 204. The transmission / reception unit 203 can be configured from a transmitter / receiver, a transmission / reception circuit, or a transmission / reception device described based on common recognition in the technical field according to the present disclosure. Note that the transmission / reception unit 203 may be configured as an integrated transmission / reception unit, or may be configured from a transmission unit and a reception unit.

The baseband signal processing unit 204 performs FFT processing, error correction decoding, reception processing for retransmission control, and the like on the input baseband signal. The downlink user data is transferred to the application unit 205. The application unit 205 performs processing related to layers higher than the physical layer and the MAC layer. Also, of the downlink data, broadcast information may be transferred to the application unit 205.

On the other hand, uplink user data is input from the application unit 205 to the baseband signal processing unit 204. The baseband signal processing unit 204 performs retransmission control transmission processing (eg, HARQ transmission processing), channel coding, precoding, discrete Fourier transform (DFT) processing, IFFT processing, and the like, and performs transmission / reception processing. Transferred to 203.

(4) The transmission / reception unit 203 converts the baseband signal output from the baseband signal processing unit 204 into a radio frequency band and transmits the radio frequency band. The radio frequency signal frequency-converted by the transmitting / receiving section 203 is amplified by the amplifier section 202 and transmitted from the transmitting / receiving antenna 201.

Further, the transmitting / receiving section 203 converts a demodulation reference signal (DMRS) having a waveform (DFT-s-OFDM) or a single carrier waveform to which conversion precoding is applied, and a waveform or single carrier waveform to which conversion precoding is applied. The received downlink control information (DCI, signal obtained by DCI modulation and mapping) may be received. The demodulation reference signal (PDCCH @ DMRS) may be associated with DCI. The PDCCH @ DMRS may be mapped to a RE in the CORESET. For example, if the upper layer parameter CORESET-precoder-granularity is equal to the REG bundle size of CORESET, the PDCCH @ DMRS may be mapped to the REs in the RE group that make up the PDCCH that the UE attempts to decode. For example, if the upper layer parameter CORESET-precoder-granularity is equal to the size of CORESET in the frequency domain, PDCCH @ DMRS may be mapped to all RE groups in the set of consecutive RBs where UEs in CORESET attempt to decode PDCCH. Good. Complex value symbols based on downlink control information may be mapped to REs used for the monitored PDCCH and not used for the associated PDCCH @ DMRS.

The transmission / reception unit 203 includes information on a PDCCH monitoring configuration (for example, a monitoring cycle, a slot offset, a symbol offset, and a monitoring time length), information on a correspondence between a new melology (for example, SCS) and the monitoring configuration, information on a RESET configuration, Information about the SCS or the like may be received from the wireless base station 10.

FIG. 8 is a diagram illustrating an example of a functional configuration of the user terminal according to the embodiment. Note that, in this example, functional blocks of characteristic portions in the present embodiment are mainly shown, and it may be assumed that the user terminal 20 also has other functional blocks necessary for wireless communication.

The baseband signal processing unit 204 of the user terminal 20 includes at least a control unit 401, a transmission signal generation unit 402, a mapping unit 403, a reception signal processing unit 404, and a measurement unit 405. Note that these configurations need only be included in the user terminal 20, and some or all of the configurations need not be included in the baseband signal processing unit 204.

The control unit 401 controls the entire user terminal 20. The control unit 401 can be configured by a controller, a control circuit, or a control device described based on common recognition in the technical field according to the present disclosure.

The control unit 401 controls, for example, signal generation in the transmission signal generation unit 402, signal assignment in the mapping unit 403, and the like. Further, the control unit 401 controls signal reception processing in the reception signal processing unit 404, signal measurement in the measurement unit 405, and the like.

The control unit 401 acquires the downlink control signal and the downlink data signal transmitted from the radio base station 10 from the reception signal processing unit 404. The control unit 401 controls generation of an uplink control signal and / or an uplink data signal based on a result of determining whether or not retransmission control is required for a downlink control signal and / or a downlink data signal.

The control unit 401 may demodulate the downlink control information time-division multiplexed with the demodulation reference signal based on the demodulation reference signal.

The demodulation reference signal may be mapped to one continuous frequency resource or a plurality of equally spaced frequency resources. The downlink control information may be mapped to one continuous frequency resource or a plurality of frequency resources having equal intervals.

In addition, the time resources allocated to the downlink control channel candidates having the first aggregation level (for example, 2, 4, 8, 16) have a second aggregation level (for example, 1, 2, or 4) lower than the first aggregation level. 4, 8) may be more than the time resources allocated to the downlink control channel candidates.

Further, the control unit 401 performs downlink control based on at least one of a frequency band of a downlink control channel, a received synchronization signal, a received broadcast channel (for example, PBCH), and higher layer signaling (for example, RRC signaling). The configuration of the channel candidates may be determined.

{Also, the resources allocated to the downlink control information candidates having the first aggregation level may include the resources allocated to the downlink control information candidates having the second aggregation level lower than the first aggregation level.

Transmission signal generating section 402 generates an uplink signal (uplink control signal, uplink data signal, uplink reference signal, etc.) based on an instruction from control section 401 and outputs the generated signal to mapping section 403. The transmission signal generation unit 402 can be configured from a signal generator, a signal generation circuit, or a signal generation device described based on common recognition in the technical field according to the present disclosure.

(4) The transmission signal generation unit 402 generates an uplink control signal related to acknowledgment information, channel state information (CSI), and the like based on an instruction from the control unit 401, for example. Further, transmission signal generating section 402 generates an uplink data signal based on an instruction from control section 401. For example, the transmission signal generation unit 402 is instructed by the control unit 401 to generate an uplink data signal when the downlink control signal notified from the radio base station 10 includes an UL grant.

Mapping section 403 maps the uplink signal generated by transmission signal generation section 402 to a radio resource based on an instruction from control section 401, and outputs the result to transmission / reception section 203. The mapping unit 403 can be configured from a mapper, a mapping circuit, or a mapping device described based on common recognition in the technical field according to the present disclosure.

(4) The reception signal processing unit 404 performs reception processing (for example, demapping, demodulation, and decoding) on the reception signal input from the transmission / reception unit 203. Here, the received signal is, for example, a downlink signal (a downlink control signal, a downlink data signal, a downlink reference signal, etc.) transmitted from the radio base station 10. The reception signal processing unit 404 can be configured from a signal processor, a signal processing circuit, or a signal processing device described based on common recognition in the technical field according to the present disclosure. In addition, the reception signal processing unit 404 can configure a reception unit according to the present disclosure.

(4) The reception signal processing unit 404 outputs the information decoded by the reception processing to the control unit 401. The reception signal processing unit 404 outputs, for example, broadcast information, system information, RRC signaling, DCI, and the like to the control unit 401. Further, the reception signal processing unit 404 outputs the reception signal and / or the signal after the reception processing to the measurement unit 405.

The measurement unit 405 performs measurement on the received signal. The measurement unit 405 can be configured from a measurement device, a measurement circuit, or a measurement device described based on common recognition in the technical field according to the present disclosure.

For example, the measurement unit 405 may perform RRM measurement, CSI measurement, and the like based on the received signal. The measurement unit 405 may measure reception power (for example, RSRP), reception quality (for example, RSRQ, SINR, SNR), signal strength (for example, RSSI), channel information (for example, CSI), and the like. The measurement result may be output to the control unit 401.

(Hardware configuration)
Note that the block diagram used in the description of the above-described embodiment shows blocks in functional units. These functional blocks (components) are realized by an arbitrary combination of at least one of hardware and software. In addition, a method for implementing each functional block is not particularly limited. That is, each functional block may be realized using one device physically or logically combined, or directly or indirectly (for example, two or more devices physically or logically separated). , Wired, wireless, etc.) and using these multiple devices.

For example, a wireless base station, a user terminal, or the like according to an embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method according to the present disclosure. FIG. 9 is a diagram illustrating an example of a hardware configuration of the radio base station and the user terminal according to the embodiment. The above-described wireless base station 10 and user terminal 20 may be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, and the like. Good.

In the following description, the term “apparatus” can be read as a circuit, a device, a unit, or the like. The hardware configuration of the radio base station 10 and the user terminal 20 may be configured to include one or more devices shown in the drawing, or may be configured without including some devices.

For example, although only one processor 1001 is illustrated, there may be multiple processors. Further, the processing may be executed by one processor, or the processing may be executed by two or more processors simultaneously, sequentially, or by using another method. Note that the processor 1001 may be implemented by one or more chips.

The functions of the radio base station 10 and the user terminal 20 are performed by, for example, reading predetermined software (program) on hardware, such as the processor 1001 and the memory 1002, so that the processor 1001 performs an arithmetic operation and the communication device 1004 via the communication device 1004. It is realized by controlling communication and controlling at least one of reading and writing of data in the memory 1002 and the storage 1003.

The processor 1001 controls the entire computer by operating an operating system, for example. The processor 1001 may be configured by a central processing unit (CPU: Central Processing Unit) including an interface with a peripheral device, a control device, an arithmetic device, a register, and the like. For example, the above-described baseband signal processing unit 104 (204), call processing unit 105, and the like may be realized by the processor 1001.

The processor 1001 reads out a program (program code), a software module, data, and the like from at least one of the storage 1003 and the communication device 1004 to the memory 1002, and executes various processes according to these. As the program, a program that causes a computer to execute at least a part of the operation described in the above embodiment is used. For example, the control unit 401 of the user terminal 20 may be implemented by a control program stored in the memory 1002 and operated by the processor 1001, and other functional blocks may be similarly implemented.

The memory 1002 is a computer-readable recording medium, and includes, for example, at least one of a ROM (Read Only Memory), an EPROM (Erasable Programmable ROM), an EEPROM (Electrically EPROM), a RAM (Random Access Memory), and other appropriate storage media. It may be constituted by one. The memory 1002 may be called a register, a cache, a main memory (main storage device), or the like. The memory 1002 can store a program (program code), a software module, and the like that can be executed to implement the wireless communication method according to an embodiment of the present disclosure.

The storage 1003 is a computer-readable recording medium such as a flexible disk, a floppy (registered trademark) disk, a magneto-optical disk (for example, a compact disk (CD-ROM (Compact Disc) ROM, etc.)), a digital versatile disc, At least one of a Blu-ray (registered trademark) disk, a removable disk, a hard disk drive, a smart card, a flash memory device (eg, a card, a stick, a key drive), a magnetic stripe, a database, a server, and other suitable storage media. May be configured. The storage 1003 may be called an auxiliary storage device.

The communication device 1004 is hardware (transmission / reception device) for performing communication 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 a high-frequency switch, a duplexer, a filter, a frequency synthesizer, and the like, for example, in order to realize at least one of frequency division duplex (FDD: Frequency Division Duplex) and time division duplex (TDD: Time Division Duplex). May be configured. For example, the transmission / reception antenna 101 (201), the amplifier unit 102 (202), the transmission / reception unit 103 (203), the transmission line interface 106, and the like may be realized by the communication device 1004.

The input device 1005 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, and the like) that receives an external input. The output device 1006 is an output device that performs output to the outside (for example, a display, a speaker, an LED (Light Emitting Diode) lamp, and the like). Note that the input device 1005 and the output device 1006 may have an integrated configuration (for example, a touch panel).

The devices such as the processor 1001 and the memory 1002 are connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using a different bus for each device.

The radio base station 10 and the user terminal 20 include a microprocessor, a digital signal processor (DSP), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), and an FPGA (Field Programmable Gate Array). It may be configured to include hardware, and some or all of the functional blocks may be realized using the hardware. For example, the processor 1001 may be implemented using at least one of these hardware.

(Modification)
Note that terms described in the present disclosure and terms necessary for understanding the present disclosure may be replaced with terms having the same or similar meaning. For example, at least one of the channel and the symbol may be a signal (signaling). Also, the signal may be a message. The reference signal may be abbreviated as RS (Reference Signal), and may be referred to as a pilot, a pilot signal, or the like according to an applied standard. A component carrier (CC: Component Carrier) may be called a cell, a frequency carrier, a carrier frequency, or the like.

The radio frame may be configured by one or a plurality of periods (frames) in the time domain. The one or more respective periods (frames) forming the radio frame may be referred to as a subframe. Furthermore, a subframe may be configured by one or more slots in the time domain. The subframe may be of a fixed length of time (eg, 1 ms) that does not depend on numerology.

Here, the new melology may be a communication parameter applied to at least one of transmission and reception of a certain signal or channel. Numerology includes, for example, subcarrier interval (SCS: SubCarrier @ Spacing), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI: Transmission @ Time @ Interval), number of symbols per TTI, radio frame configuration, transmission and reception. At least one of a specific filtering process performed by the transceiver in the frequency domain and a specific windowing process performed by the transceiver in the time domain may be indicated.

The slot may be configured by one or more symbols (OFDM (Orthogonal Frequency Division Multiplexing) symbol, SC-FDMA (Single Carrier Frequency Division Multiple Access) symbol, etc.) in the time domain. Further, the slot may be a time unit based on numerology.

The slot may include a plurality of mini slots. Each minislot may be constituted by one or more symbols in the time domain. Also, minislots may be called subslots. A minislot may be made up of a smaller number of symbols than slots. A PDSCH (or PUSCH) transmitted in time units larger than minislots may be referred to as PDSCH (PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using minislots may be referred to as PDSCH (PUSCH) mapping type B.

Radio frames, subframes, slots, minislots, and symbols all represent time units when transmitting signals. The radio frame, the subframe, the slot, the minislot, and the symbol may have different names corresponding thereto. Note that time units such as frames, subframes, slots, minislots, and symbols in the present disclosure may be interchanged with each other.

For example, one subframe may be called a transmission time interval (TTI: Transmission @ Time @ Interval), a plurality of consecutive subframes may be called a TTI, and one slot or one minislot is called a TTI. You may. That is, at least one of the subframe and the TTI may be a subframe (1 ms) in the existing LTE, a period shorter than 1 ms (for example, 1 to 13 symbols), or a period longer than 1 ms. It may be. Note that the unit representing the TTI may be called a slot, a minislot, or the like instead of a subframe.

Here, TTI means, for example, a minimum time unit of scheduling in wireless communication. For example, in the LTE system, a radio base station performs scheduling for allocating radio resources (frequency bandwidth, transmission power, and the like that can be used in each user terminal) to each user terminal in TTI units. Note that the definition of TTI is not limited to this.

The TTI may be a transmission time unit such as a channel-encoded data packet (transport block), a code block, a code word, or a processing unit such as scheduling and link adaptation. Note that when a TTI is given, a time section (for example, the number of symbols) in which a transport block, a code block, a codeword, and the like are actually mapped may be shorter than the TTI.

If one slot or one minislot is called a TTI, one or more TTIs (ie, one or more slots or one or more minislots) may be the minimum time unit for scheduling. Further, the number of slots (mini-slot number) constituting 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), a normal TTI, a long TTI, a normal subframe, a normal subframe, a long subframe, a slot, and the like. A TTI shorter than the normal TTI may be called a shortened TTI, a short TTI, a partial TTI (partial or fractional TTI), a shortened subframe, a short subframe, a minislot, a subslot, a slot, and the like.

Note that a long TTI (for example, a normal TTI, a subframe, etc.) may be read as a TTI having a time length exceeding 1 ms, and a short TTI (for example, a shortened TTI, etc.) may be replaced with a TTI shorter than the long TTI and 1 ms. The TTI having the TTI length described above may be replaced with the TTI.

The resource block (RB: Resource Block) is a resource allocation unit in the time domain and the frequency domain, and may include one or a plurality of continuous subcarriers (subcarriers) in the frequency domain. The number of subcarriers included in the RB may be the same irrespective of the numerology, and may be, for example, 12. The number of subcarriers included in the RB may be determined based on numerology.

Ｒ Also, the RB may include one or more symbols in the time domain, and may have a length of one slot, one minislot, one subframe, or one TTI. One TTI, one subframe, and the like may each be configured by one or a plurality of resource blocks.

Note that one or a plurality of RBs include a physical resource block (PRB: Physical @ RB), a subcarrier group (SCG: Sub-Carrier @ Group), a resource element group (REG: Resource @ Element @ Group), a PRB pair, an RB pair, and the like. May be called.

{Also, a resource block may be composed of one or more resource elements (RE: Resource @ Element). For example, one RE may be a radio resource area of one subcarrier and one symbol.

A bandwidth part (BWP: Bandwidth @ Part) (which may also be referred to as a partial bandwidth or the like) may represent a subset of contiguous common RBs (common @ resource @ blocks) for a certain numerology in a certain carrier. Good. Here, the common RB may be specified by an index of the RB based on the common reference point of the carrier. A PRB may be defined in a BWP and numbered within the BWP.

$ BWP may include a BWP for UL (UL @ BWP) and a BWP for DL (DL @ BWP). For a UE, one or more BWPs may be configured in one carrier.

少 な く と も At least one of the configured BWPs may be active, and the UE may not have to assume transmitting and receiving a given signal / channel outside the active BWP. Note that “cell”, “carrier”, and the like in the present disclosure may be replaced with “BWP”.

The structures of the above-described radio frame, subframe, slot, minislot, and symbol 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, included in an RB The number of subcarriers, the number of symbols in a TTI, the symbol length, the configuration such as the cyclic prefix (CP) length can be variously changed.

Further, the information, parameters, and the like described in the present disclosure may be represented using an absolute value, may be represented using a relative value from a predetermined value, or may be represented using another corresponding information. May be represented. For example, a radio resource may be indicated by a predetermined index.

名称 Names used for parameters and the like in the present disclosure are not limited in any way. Further, the formulas and the like using these parameters may be different from those explicitly disclosed in the present disclosure. The various channels (PUCCH (Physical Uplink Control Channel), PDCCH (Physical Downlink Control Channel), etc.) and information elements can be identified by any suitable name, so the various names assigned to these various channels and information elements Is not a limiting name in any way.

The information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc., that can be referred to throughout the above description are not limited to voltages, currents, electromagnetic waves, magnetic or magnetic particles, optical or photons, or any of these. May be represented by a combination of

情報 In addition, information, signals, and the like can be output from the upper layer to at least one of the lower layer and the lower layer to at least one of the upper layer. Information, signals, and the like may be input and output via a plurality of network nodes.

(4) Information and signals input and output may be stored in a specific location (for example, a memory) or may be managed using a management table. Information and signals that are input and output can be overwritten, updated, or added. The output information, signal, and the like may be deleted. The input information, signal, and the like may be transmitted to another device.

Notification of information is not limited to the aspect / embodiment described in the present disclosure, and may be performed using another method. For example, the information is notified by physical layer signaling (for example, downlink control information (DCI: Downlink Control Information), uplink control information (UCI: Uplink Control Information)), upper layer signaling (for example, RRC (Radio Resource Control) signaling, It may be implemented by broadcast information (master information block (MIB: Master Information Block), system information block (SIB: System Information Block), etc.), MAC (Medium Access Control) signaling), other signals, or a combination thereof.

{Note that the physical layer signaling may be called L1 / L2 (Layer 1 / Layer 2) control information (L1 / L2 control signal), L1 control information (L1 control signal), or the like. The RRC signaling may be called an RRC message, and may be, for example, an RRC connection setup (RRCConnectionSetup) message, an RRC connection reconfiguration (RRCConnectionReconfiguration) message, or the like. Also, the MAC signaling may be notified using, for example, a MAC control element (MAC @ CE (Control @ Element)).

In addition, the notification of the predetermined information (for example, the notification of “X”) is not limited to an explicit notification, and is implicit (for example, by not performing the notification of the predetermined information or by another information). May be performed).

The determination may be made by a value represented by 1 bit (0 or 1) or by a boolean value represented by true or false. , May be performed by comparing numerical values (for example, comparison with a predetermined value).

Software, regardless of whether it is called software, firmware, middleware, microcode, a hardware description language, or any other name, instructions, instruction sets, codes, code segments, program codes, programs, subprograms, software modules , Applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, and the like.

ソ フ ト ウ ェ ア In addition, software, instructions, information, and the like may be transmitted and received via a transmission medium. For example, if the software uses at least one of wired technology (coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), etc.) and wireless technology (infrared, microwave, etc.), the website, When transmitted from a server or other remote source, at least one of these wired and / or wireless technologies is included within the definition of a transmission medium.

用語 As used in this disclosure, the terms “system” and “network” may be used interchangeably.

In the present disclosure, “precoding”, “precoder”, “weight (precoding weight)”, “transmission power”, “phase rotation”, “antenna port”, “layer”, “number of layers”, “rank”, Terms such as “beam”, “beam width”, “beam angle”, “antenna”, “antenna element”, “panel” and the like may be used interchangeably.

In the present disclosure, “base station (BS: Base @ Station)”, “wireless base station”, “fixed station (fixed @ station)”, “NodeB”, “eNodeB (eNB)”, “gNodeB (gNB)”, “ "Access point (access @ point)", "transmission point (TP: Transmission @ Point)", "reception point (RP: Reception @ Point)", "transmission / reception point (TRP: Transmission / Reception @ Point)", "panel", "cell" Terms such as, "sector", "cell group", "carrier", "component carrier" may be used interchangeably. A base station may be referred to by a term such as a macro cell, a small cell, a femto cell, a pico cell, and the like.

A base station can accommodate one or more (eg, three) cells. If the base station accommodates multiple cells, the entire coverage area of the base station can be partitioned into multiple smaller areas, each smaller area being a base station subsystem (eg, a small indoor base station (RRH: Communication services can also be provided by Remote Radio 通信 Head)). The term “cell” or “sector” refers to part or all of the coverage area of at least one of a base station and a base station subsystem that provide communication services in this coverage.

In the present disclosure, terms such as “mobile station (MS)”, “user terminal”, “user equipment” (UE), and “terminal” may be used interchangeably. .

A mobile station is a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal. , A handset, a user agent, a mobile client, a client or some other suitable terminology.

少 な く と も At least one of the base station and the mobile station may be called a transmitting device, a receiving device, or the like. Note that at least one of the base station and the mobile station may be a device mounted on the mobile unit, the mobile unit 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 (maned or unmanned). ). Note that at least one of the base station and the mobile station includes a device that does not necessarily move during a communication operation.

無線 In addition, the wireless base station in the present disclosure may be replaced with a user terminal. For example, communication between a radio base station and a user terminal is replaced with communication between a plurality of user terminals (for example, may be called D2D (Device-to-Device), V2X (Vehicle-to-Everything), etc.). Each aspect / embodiment of the present disclosure may be applied to the configuration described above. In this case, the configuration may be such that the user terminal 20 has the function of the wireless base station 10 described above. Further, words such as “up” and “down” may be read as words corresponding to communication between terminals (for example, “side”). For example, an uplink channel, a downlink channel, and the like may be replaced with a side channel.

Similarly, the user terminal in the present disclosure may be replaced with a wireless base station. In this case, the configuration may be such that the wireless base station 10 has the functions of the user terminal 20 described above.

In the present disclosure, an operation performed by the base station may be performed by an upper node (upper node) in some cases. In a network including one or more network nodes having a base station (network @ nodes), various operations performed for communication with a terminal include a base station, one or more network nodes other than the base station (eg, Obviously, it can be performed by MME (Mobility @ Management @ Entity), S-GW (Serving-Gateway), etc., but not limited thereto, or a combination thereof.

各 Each aspect / embodiment described in the present disclosure may be used alone, may be used in combination, or may be switched and used in execution. In addition, the order of the processing procedure, sequence, flowchart, and the like of each aspect / embodiment described in the present disclosure may be changed as long as there is no inconsistency. For example, for the methods described in this disclosure, elements of the various steps are presented in an exemplary order, and are not limited to the specific order presented.

Each aspect / embodiment described in the present disclosure is applicable to LTE (Long Term Evolution), LTE-A (LTE-Advanced), LTE-B (LTE-Beyond), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication). system), 5G (5th generation mobile communication system), FRA (Future Radio Access), New-RAT (Radio Access Technology), NR (New Radio), NX (New radio access), FX (Future generation radio access), GSM (Registered trademark) (Global System for Mobile Communications), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802. 20, UWB (Ultra-WideBand), Bluetooth (registered trademark) , A system using other appropriate wireless communication methods, a next-generation system extended based on these systems, and the like. A plurality of systems may be combined (for example, a combination of LTE or LTE-A and 5G) and applied.

記載 The term "based on" as used in the present disclosure does not mean "based solely on" unless stated otherwise. In other words, the description "based on" means both "based only on" and "based at least on."

い か な る Any reference to elements using designations such as "first," "second," etc., as used in the present disclosure, does not generally limit the quantity or order of those elements. These designations may be used in the present disclosure as a convenient way to distinguish between two or more elements. Thus, reference to a first and second element does not mean that only two elements can be employed or that the first element must precede the second element in some way.

用語 The term "determining" as used in this disclosure may encompass a wide variety of actions. For example, “judgment (decision)” means judging, calculating, computing, processing, deriving, investigating, looking up (for example, a table, Searching in a database or another data structure), ascertaining, etc., may be regarded as "deciding".

In addition, “determination” includes receiving (eg, receiving information), transmitting (eg, transmitting information), input (input), output (output), and access ( accessing) (e.g., accessing data in a memory) or the like.

Also, “judgment (decision)” is regarded as “judgment (decision)” of resolving, selecting, selecting, establishing, comparing, and the like. Is also good. That is, “judgment (decision)” may be regarded as “judgment (decision)” of any operation.

判断 Also, “judgment (decision)” may be read as “assuming”, “expecting”, “considering”, or the like.

The “maximum transmission power” described in the present disclosure may mean the maximum value of the transmission power, may mean the nominal maximum transmission power (the nominal UE maximum transmit power), or may refer to the rated maximum transmission power (the rated UE maximum transmit power).

As used in this disclosure, the terms "connected," "coupled," or any variation thereof, refer to any direct or indirect connection or coupling between two or more elements. And may include the presence of one or more intermediate elements between two elements "connected" or "coupled" to each other. The coupling or connection between the elements may be physical, logical, or a combination thereof. For example, “connection” may be read as “access”.

In the present disclosure, where two elements are connected, using one or more wires, cables, printed electrical connections, etc., and as some non-limiting and non-exhaustive examples, the radio frequency domain, microwave It can be considered to be "connected" or "coupled" to each other using electromagnetic energy having a wavelength in the region, the light (both visible and invisible) regions, and the like.

に お い て In the present disclosure, the term “A and B are different” may mean that “A and B are different from each other”. The term may mean that “A and B are different from C”. Terms such as "separate" and "coupled" may be construed similarly to "different."

Where the terms “include”, “including” and variations thereof are used in the present disclosure, these terms are as inclusive as the term “comprising” Is intended. Further, the term "or" as used in the present disclosure is not intended to be an exclusive or.

In the present disclosure, if articles are added by translation, for example, a, an and the in English, the present disclosure may include that the nouns following these articles are plural.

Although the invention according to the present disclosure has been described in detail above, it is obvious to those skilled in the art that the invention according to the present disclosure is not limited to the embodiments described in the present disclosure. The invention according to the present disclosure can be embodied as modifications and changes without departing from the spirit and scope of the invention determined based on the description in the claims. Therefore, the description of the present disclosure is intended to be illustrative and does not bring any restrictive meaning to the invention according to the present disclosure.

Claims (6)

A demodulation reference signal having a waveform or a single-carrier waveform to which conversion precoding has been applied, and a downlink control information having a waveform or a single-carrier waveform to which conversion precoding has been applied, a receiving unit that receives the
A user terminal, comprising: a control unit configured to demodulate the downlink control information time-division multiplexed with the demodulation reference signal based on the demodulation reference signal. The demodulation reference signal is mapped to one continuous frequency resource or a plurality of frequency resources having equal intervals,
The user terminal according to claim 1, wherein the downlink control information is mapped to one continuous frequency resource or a plurality of frequency resources having equal intervals. The time resources allocated to the downlink control channel candidates having the first aggregation level are more than the time resources allocated to the downlink control channel candidates having the second aggregation level lower than the first aggregation level. The user terminal according to claim 1. The control unit determines a configuration of a downlink control channel candidate based on at least one of a frequency band of a downlink control channel, a received synchronization signal, a received broadcast channel, and higher layer signaling. The user terminal according to any one of claims 1 to 3. The resource allocated to the downlink control information candidate having the first aggregation level includes the resource allocated to the downlink control information candidate having the second aggregation level lower than the first aggregation level. The user terminal according to any one of claims 1 to 4. A demodulation reference signal having a waveform or a single-carrier waveform to which conversion precoding has been applied, and a downlink control information having a waveform or a single-carrier waveform to which conversion precoding has been applied,
A radio base station, comprising: a control unit that maps the downlink control information time-division multiplexed to the demodulation reference signal used for demodulation of the downlink control information.

Images