Terminal, base station, communication system, and communication method

Abstract

To enable effective and reliable transmission of a synchronization signal / a broadcast channel block (SSB) at a high frequency band which is a frequency band for FR2(Frequency Range 2) of NR(New Radio) or higher, with minimum specification change.SOLUTION: A terminal for performing communication at a first frequency band and at a second frequency band whose frequency is higher than the first frequency band includes: a reception unit for receiving first setting information including a QCL (Quasi co-location) parameter selected from the number of candidates less than the number of candidates used at the first frequency band and receiving second setting information capable of setting a discovery burst transmission window which has the maximum value and the minimum value shorter than the length of a discovery burst transmission window at the first frequency band; and a control unit for setting the QCL parameter based on the first setting information and for setting the length of the discovery burst transmission window based on the second setting information.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a terminal and a base station in a wireless communication system.

Background Art

[0002] In Release 15 of NR (New Radio) and Release 16 of 3GPP (Third Generation Partnership Project), the frequency band up to 52.6 GHz is targeted. Regarding the extension of NR to a frequency band of 52.6 GHz or higher, in Release 16, there is a study item at the TSG RAN (Technical Specification Group Radio Access Network) level to consider various regulations, use cases, requirements, etc. The study of this study item was completed in December 2019, and in Release 17, a study item and a work item for actually extending the specification to 52.6 GHz or higher have been agreed upon.

[0003] In the study items in Release 16, it was assumed that the NR frequency band would be extended from 52.6 GHz to 114.25 GHz. However, in Release 17, due to limited study time, it is assumed that the frequency band to be studied will be limited to from 52.6 GHz to 71 GHz. Furthermore, when extending the NR frequency band from 52.6 GHz to 71 GHz, it is assumed that the extension will be performed based on the current NR FR2 (Frequency Range 2) design.

Prior Art Documents

Non-Patent Documents

[0004]

Non-Patent Document 1

[0005] Since the frequency band from 52.6 GHz to 71 GHz includes the 60 GHz unlicensed band, as a function extension corresponding to the frequency band from 52.6 GHz to 71 GHz, a function extension for the licensed frequency band and a function extension for the unlicensed frequency may be required.

[0006] In the high frequency band above the frequency band of FR2 of NR, a technology that enables efficient and reliable SSB transmission with a minimum change from the FR2 specification is required.

Means for Solving the Problem

[0007] According to one aspect of the present invention, there is provided a terminal in a wireless communication system that communicates in a first frequency band and a second frequency band having a frequency higher than the first frequency band, the terminal including first setting information including QCL (Quasi co-location) parameters selected from a smaller number of candidates than the number of candidates used in the first frequency band, regarding reception of a synchronization signal block in the second frequency band, and second setting information capable of setting a discovery reverse transmission window length having a maximum value and a minimum value smaller than the length of the discovery reverse transmission window in the first frequency band and having a fine granularity, a receiving unit that receives the second setting information, and a control unit that sets the QCL parameters based on the first setting information and sets the length of the discovery reverse transmission window based on the second setting information, wherein the receiving unit is assumed to receive the synchronization signal blocks in the discovery reverse transmission window whose number is equal to or less than the value of the QCL parameters set by the control unit.

Advantages of the Invention

[0008] According to an embodiment, a technique is provided that enables efficient and reliable SSB transmission with a minimum change from the specifications of FR2 in a high frequency band above the frequency band of FR2 of NR.

Brief Description of the Drawings

[0009]

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Modes for Carrying Out the Invention

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the embodiments described below are merely examples, and the embodiments to which the present invention is applied are not limited to the following embodiments.

[0011] The wireless communication system in the following embodiments is basically assumed to comply with NR, but this is just an example. The wireless communication system in this embodiment may comply with a wireless communication system other than NR (e.g., LTE) in part or in whole.

[0012] (Overall System Configuration) FIG. 1 shows a configuration diagram of the wireless communication system according to this embodiment. As shown in FIG. 1, the wireless communication system according to this embodiment includes a terminal 10 and a base station 20. In FIG. 1, one terminal 10 and one base station 20 are shown, but this is an example, and there may be a plurality of each.

[0013] The terminal 10 is a communication device equipped with a wireless communication function such as a smartphone, a mobile phone, a tablet, a wearable terminal, and a communication module for M2M (Machine-to-Machine). The terminal 10 receives a control signal or data from the base station 20 in DL and transmits a control signal or data to the base station 20 in UL, thereby using various communication services provided by the wireless communication system. For example, the channels transmitted from the terminal 10 include a PUCCH (Physical Uplink Control Channel) and a PUSCH (Physical Uplink Shared Channel). Also, the terminal 10 may be referred to as a UE, and the base station 20 may be referred to as a gNB.

[0014] In this embodiment, the duplex mode may be a TDD (Time Division Duplex) mode or an FDD (Frequency Division Duplex) mode.

[0015] In addition, in the embodiments, the phrase "configured" for wireless parameters or the like may mean that predetermined values are pre-configured, or may mean that they are configured based on wireless parameters notified from the base station 20 or the terminal 10.

[0016] The base station 20 is a communication device that provides one or more cells and performs wireless communication with the terminal 10. The physical resources of the wireless signal are defined in the time domain and the frequency domain. The time domain may be defined by the number of OFDM symbols, and the frequency domain may be defined by the number of sub-carriers or the number of resource blocks. The base station 20 transmits synchronization signals and system information to the terminal 10. The synchronization signals are, for example, NR-PSS and NR-SSS. A part of the system information is transmitted, for example, by NR-PBCH, and is also referred to as broadcast information. The synchronization signals and the broadcast information may be periodically transmitted as an SS block (SS / PBCH block) composed of a predetermined number of OFDM symbols. For example, the base station 20 transmits control signals or data to the terminal 10 in the DL (Downlink) and receives control signals or data from the terminal 10 in the UL (Uplink). Both the base station 20 and the terminal 10 are capable of performing beamforming for signal transmission and reception. For example, the reference signal transmitted from the base station 20 includes CSI-RS (Channel State Information Reference Signal), and the channels transmitted from the base station 20 include PDCCH (Physical Downlink Control Channel) and PDSCH (Physical Downlink Shared Channel).

[0017] (Extension of NR to frequency bands above 52.6 GHz) In Releases 15 and 16 of 3GPP (Third Generation Partnership Project)'s NR (New Radio), the frequency bands up to 52.6 GHz are targeted. Regarding the extension of NR to frequency bands above 52.6 GHz, in Release 16, there is a study item at the TSG RAN (Technical Specification Group Radio Access Network) level to consider various regulations, use cases, requirements, etc. The consideration of this study item was completed in December 2019, and in Release 17, study items and work items for actually extending the specifications to above 52.6 GHz have been agreed upon.

[0018] In the study items in Release 16, it was assumed that the NR frequency band would be extended from 52.6 GHz to 114.25 GHz. However, in Release 17, due to limited study time, as shown in Figure 2, it is assumed that the frequency band to be studied will be limited to from 52.6 GHz to 71 GHz. Furthermore, when extending the NR frequency band from 52.6 GHz to 71 GHz, it is assumed that the extension will be carried out based on the current NR's FR2 (Frequency Range 2) design. This is because it is assumed that it would take a considerable amount of time to study a new waveform.

[0019] Also, as a reason for limiting the frequency band under consideration to 52.6 GHz to 71 GHz, for example, below 71 GHz, there already exist frequency bands such as 54 GHz to 71 GHz as unlicensed frequency bands that can be used in various countries, and at the World Radiocommunication Conference 2019 (WRC-2019), 66 GHz to 71 GHz is the highest frequency band among the candidates for new frequency bands for IMT (International Mobile Telecommunications). Above 71 GHz, there is no frequency band that can be immediately used as a licensed band.

[0020] The current frequency bands for NR are composed of FR1 (Frequency Range 1) corresponding to the frequency band from 410 MHz to 7.125 GHz and FR2 corresponding to the frequency band from 24.25 GHz to 52.6 GHz.

[0021] Regarding the frequency band from 52.6 GHz to 71 GHz, the definition of the current FR2 (frequency band from 24.25 GHz to 52.6 GHz) can be changed and it can be included in the changed FR2. Alternatively, it can be separated from FR2 and used as a new Frequency Range (FR).

[0022] (Work Item's Objectives) (RAN1: Physical Layer Characteristics) For the new one or more numerologies for the operation of the terminal 10 and the base station 20 in the frequency band from 52.6 GHz to 71 GHz. If there is an impact on the physical signals / channels specified in the Study Item (SI), address that impact.

[0023] Features related to the timeline adapted to each new numerology. For example, the time required and calculated for each of BWP (Bandwidth Part) and beam switching time, HARQ (Hybrid Automatic Repeat Request) scheduling, UE (User Equipment) processing, PDSCH (Physical Downlink Shared Channel), PUSCH (Physical Uplink Shared Channel) / SRS (Sounding Reference Signal), and CSI (Channel State Information).

[0024] Up to 64 SSB (Synchronization Signal Block) beams for operation in licensed frequency bands and operation in unlicensed frequency bands in the frequency band from 52.6 GHz to 71 GHz.

[0025] (RAN1: Physical layer procedures) A channel access mechanism assuming beam-based operation to comply with the regulatory requirements applied to the unlicensed frequency band between 52.6 GHz and 71 GHz.

[0026] (RAN4: Core specifications regarding UE, gNB, and RRM (Radio Resource Management) requirements) Specification of the RF core requirements for gNB and UE in the frequency band from 52.6 GHz to 71 GHz. Includes a limited set of band combinations.

[0027] (Overview of SSB) An SSB is a synchronization signal / notification channel block composed of a synchronization signal (SS) and a notification channel (PBCH). It is periodically transmitted from the base station 20 for the terminal 10 to detect the cell ID and reception timing at the start of communication. In NR, the SSB is also diverted for reception quality measurement of each cell.

[0028] In NR of Release 15, for the SSB for the serving cell, it is possible to select the transmission period for transmitting the SSB. Specifically, it is possible to select the transmission period of the SSB from among 5 ms, 10 ms, 20 ms, 40 ms, 80 ms, and 160 ms. At the time of initial access, since the terminal 10 cannot receive information such as RRC (Radio Resource Control) information, 20 ms is assumed as the transmission period of the SSB. Therefore, it is assumed that in a cell that operates stand-alone corresponding to initial access, the SSB is often transmitted with a transmission period of 20 ms or less.

[0029] Also, for SSB, it is possible to notify the index of the beam (SS / PBCH block index) actually used to transmit the SSB. Regarding the index of the beam actually used to transmit the SSB, it can be notified by the information element (IE) SSB-PositionsInBurst in SIB1 or RRC signaling. In FR1, since it is possible to transmit up to 8 SSBs with 8 corresponding beams, the index of the beam actually used to transmit the SSB is notified by an 8-bit bitmap. In FR2, since it is possible to transmit up to 64 SSBs with 64 corresponding beams, in RRC signaling, the index of the beam actually used to transmit the SSB is notified by a 64-bit bitmap. However, including a 64-bit bitmap in SIB1 increases the overhead. Therefore, when notifying the index of the beam actually transmitted in SIB1, the index of the beam is notified by a total of 16 bits, which is the sum of an 8-bit bitmap and an 8-bit group bitmap. That is, the 64 beams corresponding to 64 SSBs are divided into a total of 8 groups, each group containing 8 SSB beams. An 8-bit bitmap indicating which SSB beam is transmitted within each group, and an 8-bit bitmap for the entire group indicating which group among the 8 groups transmits the SSB beam are used to notify the index of the beam of the SSB actually transmitted. Also, in FR1 and FR2 excluding unlicensed frequencies, since the position where SSB transmission is possible for each beam is one in each half-frame as described later, the notification of the beam index (SS / PBCH block index) actually used to transmit the SSB can also be interpreted as the notification of at which time resource within the half-frame the SSB is transmitted, and it is used for rate matching during PDSCH reception.

[0030] As an index related to the SSB, in addition to the index of the beam (SS / PBCH block index) actually used to transmit the SSB described above, a candidate SS / PBCH block index is defined. The candidate SS / PBCH block index is an index that specifies positions within a half-frame where the SSB can be transmitted by a beam. In FR1 excluding unlicensed frequencies, it is possible to transmit up to 8 SSBs with 8 beams corresponding to them. Since there only needs to be one position within the half-frame where SSB transmission is possible for each beam, if the indices from 0 to 7 are associated with the SSB, it is possible to identify the candidate SS / PBCH block index. Therefore, 3 bits are required to identify the candidate SS / PBCH block index. Since it is possible to generate 8 patterns with the sequence pattern of the DMRS (Demodulation Reference Signal) of the PBCH (Physical Broadcast Channel) within the same cell, it is possible to recognize the 3 bits for identifying the candidate SS / PBCH block index based on this sequence pattern.

[0031] In FR2, it is possible to transmit with up to 64 beams corresponding to 64 SSBs. Since there only needs to be one position where SSB transmission is possible for each beam within a half-frame, if the indexes from 0 to 63 are associated with the SSBs, it is possible to identify the candidate SSB position indexes. Therefore, 6 bits are required to identify the candidate SSB position indexes. Increasing the number of patterns of the DMRS sequence of the PBCH may reduce the detection performance of the DMRS. For this reason, the DMRS sequence of the PBCH has 8 patterns within the same cell. The remaining 3 bits for identifying 64 candidate SSB position indexes are transmitted within the payload of the PBCH. That is, in FR2, the 3 LSBs (Least Significant Bits) of the candidate SSB position index are recognized by the DMRS sequence of the PBCH, and the 3 MSBs (Most Significant Bits) of the candidate SSB position index are recognized by the information transmitted within the payload of the PBCH.

[0032] Regarding the measurement based on SSB in Release 15 NR, a function for the base station 20 to notify the terminal 10 of the measurement period and timing of the SSB used by the terminal 10 for measurement (SMTC window (SSB based RRM Measurement Timing Configuration window) set by the information element SSB-MTC) has been introduced. The SMTC window is a measurement window set by the base station 20 for the terminal 10 to notify the terminal 10 of the measurement start timing, measurement period, and measurement period for each cell to be measured when the terminal 10 performs reception quality measurement using the SSB. The period of the SMTC window can be selected from 5 ms, 10 ms, 20 ms, 40 ms, 80 ms, and 160 ms. Also, the granularity of the offset of the SMTC window is 1 ms. Also, the duration of the SMTC window can be selected from 1 ms, 2 ms, 3 ms, 4 ms, and 5 ms. The base station 20 can notify the beam index of the SSB to be measured using the information element SSB-ToMeasure. For FR1, it is possible to notify the beam index of the SSB to be measured with an 8-bit bitmap, and for FR2, it is possible to notify the beam index of the SSB to be measured with a 64-bit bitmap.

[0033] (Function Extensions Related to SSB in New Radio Unlicensed (NR-U) of Release 16) Since NR-U is an unlicensed band, it is assumed to coexist with other communication systems such as Wi-Fi and other NR-U systems. Therefore, when the NR-U terminal 10 and / or base station 20 starts transmission in the unlicensed frequency band, the NR-U terminal 10 and / or base station 20 is assumed to perform Listen Before Talk (LBT) in order to confirm that there are no other terminals (e.g., terminals compatible with the Wi-Fi 802.11ac standard) or base stations (e.g., access points compatible with the Wi-Fi 802.11ac standard) transmitting in the vicinity. LBT is a communication method that performs carrier sensing before starting transmission and enables transmission within a predetermined time length only when it is confirmed that the channel is not being used by other nearby systems.

[0034] It is not preferable that reference signals such as SSB, which are used to maintain cell connection and measure signal quality, are not transmitted for LBT. However, it is also not preferable to transmit SSB when other systems are transmitting signals. Therefore, the transmission candidate positions of SSB have been extended. If SSB cannot be transmitted at the transmission candidate position where SSB was originally scheduled to be transmitted, such as when other systems are transmitting signals, SSB may be transmitted at the subsequent transmission candidate position. In the unlicensed band of FR1, subcarrier spacings (SCS) of 15 kHz and 30 kHz can be used for SSB. In the unlicensed band of FR1, when using an SCS of 15 kHz, the transmission candidate positions of SSB are extended to 10. Also, in the unlicensed band of FR1, when using an SCS of 30 kHz, the transmission candidate positions of SSB are extended to 20. That is, there is at least one position where SSB can be transmitted in each beam within a half frame.

[0035] For example, as shown in FIG. 2, when the SCS is 30 kHz, two transmission candidate positions of the SSB may be set for each slot within a 5 ms half-frame. The upper limit of the number of SSBs that can actually be transmitted is eight. Among the 20 transmission candidate positions of the SSB shown in FIG. 2, the required number of SSBs may be transmitted in order from the transmission candidate position of the SSB that succeeded in LBT.

[0036] As described above, as the index of the SSB, an index indicating the position where the SSB is transmitted (which may be a position in the time domain, a position in the frequency domain, or a position in the time and frequency domains) (for example, Candidate SS / PBCH block index), and an index indicating which beam the SSB is transmitted in (SS / PBCH block index) may be defined.

[0037] For example, as shown in FIG. 2, assume that when the SCS is 30 kHz, 20 transmission candidate positions (positions in the time domain) of the SSB are set. In the example of FIG. 2, these 20 transmission candidate positions are indicated by the Candidate SS / PBCH block index. The Candidate SS / PBCH block index is information necessary for the terminal 10 to determine at what timing within 5 ms it detected the SSB, that is, to determine the frame timing.

[0038] Also, in the example of FIG. 2, for each transmission candidate position, information necessary to derive an index (SS / PBCH block index) indicating which beam among a maximum of eight beams the SSB is transmitted in, that is, QCL (Quasi co-location) information is provided. For example, when the terminal 10 reports the quality for each beam to the base station 20, the QCL information may be used.

[0039] In the example of Fig. 2, when the SCS is 30 kHz, 10 slots are included in 5 ms, and each slot contains two transmission candidate positions for SSB. For these 20 transmission candidate positions of SSB, Candidate SS / PBCH block indices from 0 to 19 are assigned in order from the beginning.

[0040] In this case, since it is possible to use 8 patterns as the DMRS sequence of PBCH, it is possible to assign indices from 0 to 7 to the transmission candidate positions of SSB according to the pattern of the DMRS sequence of PBCH. In the example of Fig. 2, DMRS sequence 0 to 7 are respectively associated with the transmission candidate positions of SSB where the Candidate SS / PBCH block index is from 0 to 7, DMRS sequence 0 to 7 are respectively associated with the transmission candidate positions of SSB where the Candidate SS / PBCH block index is from 8 to 15, and DMRS sequence 0 to 3 are respectively associated with the transmission candidate positions of SSB where the Candidate SS / PBCH block index is from 16 to 19. That is, a correspondence relationship is defined such that when the transmission candidate position of SSB is specified, the DMRS sequence of PBCH to be used is uniquely determined.

[0041] Furthermore, as shown in the example of FIG. 2, if information on the bits corresponding to the MSB of the Candidate SS / PBCH block index transmitted by the PBCH payload is obtained, the Candidate SS / PBCH block index can be uniquely determined by the MSB and the DMRS sequence. In the example of FIG. 2, the base station 20 may directly notify the terminal 10 of the Candidate SS / PBCH block index. For example, the base station 20 transmits to the terminal 10 the information on the bits corresponding to the MSB of the Candidate SS / PBCH block index and the DMRS of the PBCH, and the terminal 10 may derive the Candidate SS / PBCH block index based on the information on the bits corresponding to the MSB of the Candidate SS / PBCH block index and the DMRS sequence of the PBCH.

[0042] Also, in the example of FIG. 2, when the number of beams transmitted by the base station 20 is 8, the beams are repeated every 8 transmission candidate positions of the SSB. In the example of FIG. 2, for the transmission candidate positions of the SSB where the Candidate SS / PBCH block index ranges from 0 to 7, the SS / PBCH block indices from 0 to 7 are respectively associated, for the transmission candidate positions of the SSB where the Candidate SS / PBCH block index ranges from 8 to 15, the SS / PBCH block indices from 0 to 7 are respectively associated, and for the transmission candidate positions of the SSB where the Candidate SS / PBCH block index ranges from 16 to 19, the SS / PBCH block indices from 0 to 3 are respectively associated.

[0043] For example, every 20 ms of the SSB transmission period, a 5-ms window shown in FIG. 2 is set, and there are 20 SSB transmission candidate positions therein. Regarding which transmission candidate position the SSB is transmitted from, it may change every 20 ms of the SSB transmission period. For example, in the 20-ms SSB transmission period, for the purpose of knowing whether the beam used for the transmission of the SSB detected at the position where the Candidate SS / PBCH block index is 0 is the same beam as the beam used for the transmission of the SSB detected at the position where the Candidate SS / PBCH block index is 4 in the next 20-ms SSB transmission period, the QCL information is required. When QCL is 8, since 8 beams are repeated, the beam used for the transmission of the SSB detected at the position where the Candidate SS / PBCH block index is 0 and the beam used for the transmission of the SSB detected at the position where the Candidate SS / PBCH block index is 4 in the next 20-ms SSB transmission period are different beams (i.e., different SS / PBCH block indices). Also, the beams used for the transmission of the SSB at the positions where the Candidate SS / PBCH block indices are 0, 8, and 16 are the same beam (i.e., the same SS / PBCH block index).

[0044] Also, in the example of FIG. 2, when the base station 20 notifies the terminal 10 of 4 as the QCL parameter, four beams are used. In this case, the Candidate SS / PBCH block index is at positions from 0 to 3, and the beams with beam indices 0, 1, 2, and 3 are respectively used for transmitting the SSB in a corresponding relationship. In this case, the beams used for transmitting the SSB at the positions where the Candidate SS / PBCH block index is 0 and 4 are the same beam (i.e., the same SS / PBCH block index). For example, within the transmission period of a certain SSB, the beam used for transmitting the SSB detected at the position where the Candidate SS / PBCH block index is 0 and the beam used for transmitting the SSB detected at the position where the Candidate SS / PBCH block index is 4 in another SSB transmission period are recognized as the same beam. For example, the quality of the beam can be measured by averaging them.

[0045] Note that the QCL parameter may be notified in the payload of the PBCH.

[0046] Also, in the case of NR-U, since there are 20 candidate transmission positions for the SSB and the actual transmission position of the SSB may be different for each SSB transmission period depending on the LBT result, it is not possible to indicate at which candidate transmission position the SSB beam is being transmitted by ssb-PositionsInBurst. However, it is possible to indicate how many SSBs are being transmitted and in what pattern the SSBs are being transmitted by ssb-PositionsInBurst.

[0047] FIG. 3 is a diagram showing an example of the resource mapping structure of the SSB introduced in Release 15 of NR. This resource mapping structure of the SSB is also adopted in NR-U of Release 16, and it is assumed that the resource mapping of the SSB as shown in FIG. 3 will be adopted for the frequency band from 52.6 GHz to 71 GHz being considered in NR of Release 17.

[0048] In the following, an example is shown in which four symbols of the SSB in the time domain are mapped to the symbols in a slot, and the slot including the SSB transmission candidate position is mapped to the slot in a time unit such as 5 ms. In Release 15, five cases of Case A, B, C, D, and E are defined as such mapping.

[0049] FIG. 4 is a diagram showing an example of the SSB burst structure Case D in FR2 of NR in Release 15. In the example of FIG. 4, the SCS is 120 kHz. In the example of FIG. 4, two SSBs are mapped to be adjacent in a 120 kHz slot. Between two consecutive slots, a pattern in which the SSB is not mapped to the first four symbols and the last two symbols and a pattern in which the SSB is not mapped to the first two symbols and the last four symbols are alternately repeated. After repeating such a pattern for eight slots, two slots not including the SSB are placed. By repeating such a pattern, 64 SSB transmission candidate positions are set.

[0050] FIG. 5 is a diagram showing an example of the SSB burst structure Case E in FR2 of NR in Release 15. In the example of FIG. 5, the SCS is 240 kHz. In this case, the SCS of the SSB is 240 kHz, but the 240 kHz SCS cannot be used for data and control channels, and for data and control channels, the 60 kHz SCS or 120 kHz SCS will be used. In the example of FIG. 5, four SSBs are mapped to be adjacent in a 120 kHz slot (for data). Between two consecutive 120 kHz slots, a pattern in which the SSB is not mapped to the first eight symbols and the last four symbols and a pattern in which the SSB is not mapped to the first four symbols and the last eight symbols are alternately repeated. After repeating such a pattern for eight 120 kHz slots, two 120 kHz slots not including the SSB are placed. By repeating such a pattern, 64 SSB transmission candidate positions are set.

[0051] Figure 6 is a diagram showing an example of the SSB burst structure Case A in FR1 of NR in Release 15. In the example of Figure 6, the SCS is 15 kHz. In the example of Figure 6, within one slot, the first 2 symbols do not map the SSB, the first SSB is mapped to the subsequent 4 symbols, the subsequent 2 symbols do not map the SSB, the second SSB is mapped to the subsequent 4 symbols, and the subsequent 2 symbols do not map the SSB. In the licensed band of NR in FR1 of Release 15, by arranging 4 such slot patterns continuously, 8 SSB transmission candidate positions are set. Also, in the unlicensed band of NR in FR1 of Release 15, by arranging 5 such slot patterns continuously, 10 SSB transmission candidate positions are set.

[0052] Figure 7 is a diagram showing an example of the SSB burst structure Case C in FR1 of NR in Release 15. In the example of Figure 7, the SCS is 30 kHz. In the example of Figure 7, within one slot, the first 2 symbols do not map the SSB, the first SSB is mapped to the subsequent 4 symbols, the subsequent 2 symbols do not map the SSB, the second SSB is mapped to the subsequent 4 symbols, and the subsequent 2 symbols do not map the SSB. In the licensed band of NR in FR1 of Release 15, by arranging 4 such slot patterns continuously, 8 SSB transmission candidate positions are set. Also, in the unlicensed band of NR in FR1 of Release 15, by arranging 10 such slot patterns continuously, 20 SSB transmission candidate positions are set.

[0053] (Regarding the problem) Since the frequency band from 52.6 GHz to 71 GHz includes the 60 GHz unlicensed band, the NR system may share the 60 GHz unlicensed band with other systems (e.g., WiGig (IEEE802.11ad / ay)). Therefore, it is assumed that the terminal 10 and / or the base station 20 perform carrier sensing before starting transmission and perform Listen Before Talk (LBT) to transmit within a predetermined time length only when it is confirmed that the channel is not being used by other nearby systems. In this case, it may be impossible to transmit the SSB.

[0054] It is not preferable that reference signals such as SSB, which are used to maintain cell connection and measure signal quality, are not transmitted for LBT. However, it is also not preferable to transmit SSB when other systems are transmitting signals. Therefore, it is conceivable to expand the transmission candidate positions of SSB in the frequency band from 52.6 GHz to 71 GHz. If it is not possible to transmit SSB at the transmission candidate position where SSB was originally scheduled to be transmitted, such as when other systems are transmitting signals, SSB may be transmitted at the subsequent transmission candidate position.

[0055] Currently, it is assumed that up to 64 SSB beams are supported in the frequency band from 52.6 GHz to 71 GHz. However, it is unclear whether it is possible to transmit SSB at the subsequent transmission candidate position if it is not possible to transmit SSB at the transmission candidate position where SSB was originally scheduled to be transmitted.

[0056] Also, in the frequency band from 52.6 GHz to 71 GHz, it is assumed that a new numerology is introduced, but it is unclear how many SCSs are supported as the SSB SCS, and it is also unclear whether the new SCS is the same as or different from the current FR2 SCS (120 / 240 kHz SCS).

[0057] If it is not possible to transmit the SSB at a transmission candidate position where SSB transmission was planned in the frequency band from 52.6 GHz to 71 GHz, and it is possible to transmit the SSB at a subsequent transmission candidate position, it may be necessary to introduce an operation to detect the index of the SSB transmission candidate position for synchronizing the frame timing, and / or an operation to derive the QCL to recognize the beam index. For example, it may be necessary to change the interpretation of the bits of the PBCH payload and / or the assumptions of the terminal 10.

[0058] Also, the frequency band from 52.6 GHz to 71 GHz may include a licensed frequency band. In such a licensed frequency band, since collisions with transmissions by other systems are not assumed, functional enhancements such as in the case of NR-U may not be necessary.

[0059] Therefore, as functional enhancements corresponding to the frequency band from 52.6 GHz to 71 GHz, functional enhancements for the licensed frequency band and functional enhancements for the unlicensed frequency may be required.

[0060] (Proposal) Enable efficient and reliable SSB transmission with minimal changes from the FR2 specification in the frequency band from 52.6 GHz to 71 GHz.

[0061] In the case of operating a licensed frequency band included in the frequency band from 52.6 GHz to 71 GHz, the transmission candidate positions of the SSB within a slot may be defined based on the possible combinations of the SCS of the SSB and the SCS of the PDCCH / PDSCH.

[0062] In the case of operating an unlicensed frequency band included in the frequency band from 52.6 GHz to 71 GHz, multiple SSB transmission candidate positions may be set for each SSB beam.

[0063] In the case of operating an unlicensed frequency band included in the frequency band from 52.6 GHz to 71 GHz, the index of the SSB transmission candidate position may be from 0 to 63, and the index of the SSB transmission candidate position may be derivable from the PBCH DMRS sequence and the payload of the PBCH, similar to the case of FR2 of NR in Release 15. Note that the index of the SSB transmission candidate position may be derived from a combination of the PBCH sequence, the DMRS sequence, and the payload of the PBCH (for example, a combination of the PBCH sequence and the payload of the PBCH).

[0064] In the case of operating an unlicensed frequency band included in the frequency band from 52.6 GHz to 71 GHz, the SSB index may be from 0 to 63, and may be derived from the index of the SSB transmission candidate position and the QCL parameters in the PBCH payload. Also, the number of candidate values of the QCL parameters that can be notified in this frequency band may be different from other frequency bands (for example, it may be less than or more than the number of candidate values 4 in the frequency band of NR-U). Note that the terminal 10 may receive information from the base station 20 indicating in which slot within the window the SSB transmission candidate position is included.

[0065] In the case of operating an unlicensed frequency band included in the frequency band from 52.6 GHz to 71 GHz, the maximum length of the discovery burst transmission window may be 5 ms (for example, 2 ms when the SCS is 240 kHz), and each slot within the window may include SSB transmission candidate positions. Note that in the case of operating an unlicensed frequency band, the terminal 10 may assume that the transmission of the SSB within the half-frame is within the discovery burst transmission window. The discovery burst transmission window starts from the first symbol of the first slot within the half-frame. The base station 20 can set the time length of the discovery burst transmission window for each serving cell for the terminal 10 by means of the information element DiscoveryBurst-WindowLength-r16. If the information element DiscoveryBurst-WindowLength-r16 is not provided, the terminal 10 may assume that the time length of the discovery burst transmission window is the half-frame. The discovery burst is a downlink transmission burst that is limited to a window and includes a set of signals and / or channels associated with a duty cycle. Also, the discovery burst may be, for example, a transmission from the base station 10 including an SSB, which is composed of a primary synchronization signal (PSS), a secondary synchronization signal (SSS), a Physical broadcast channel (PBCH), and a demodulation reference signal (DM-RS) associated with the PBCH.

[0066] In the case of operating a licensed frequency band included in the frequency band from 52.6 GHz to 71 GHz, the terminal 10 may assume that the SCS of the SSB is the same as that of the SIB1 PDCCH / PDSCH (alternatively, the SCS of the SSB may be assumed to be twice that of the SIB1 PDCCH / PDSCH).

[0067] (Regarding the licensed frequency band included in the frequency band from 52.6 GHz to 71 GHz) For the licensed frequency band included in the frequency band from 52.6 GHz to 71 GHz, the transmission candidate positions of the SSB within the slot may be determined based on the possible combinations of the SCS of the SSB and the PDCCH / PDSCH SCS.

[0068] (Option 1) The combination of the SCS of the SSB and the PDCCH / PDSCH SCS may be limited to the case where the SCS of the SSB and the SCS of the PDCCH / PDSCH are the same.

[0069] FIG. 8 is a diagram showing Example 1-1 of the SSB transmission candidate position within the slot. In the example of FIG. 8, the configuration of Case D shown in FIG. 4 is reused. The number of symbols per slot may be 14. For example, 240 kHz, 480 kHz, and 960 kHz may be supported as the SCS of the SSB and the SCS of the PDCCH / PDSCH. In the example of FIG. 8, even when 240 kHz, 480 kHz, and 960 kHz are supported as the SCS of the SSB and the SCS of the PDCCH / PDSCH, the configuration of Case D shown in FIG. 4 is applied. In the example of FIG. 8, when the SCS is 240 kHz, the slot length is 0.0625 ms, when the SCS is 480 kHz, the slot length is 0.03125 ms, and when the SCS is 960 kHz, the slot length is 0.01526 ms.

[0070] In the example of FIG. 8, two SSBs are mapped to be adjacent in the slot. Between two consecutive slots, a pattern in which the SSB is not mapped to the first 4 symbols and the last 2 symbols and a pattern in which the SSB is not mapped to the first 2 symbols and the last 4 symbols are alternately repeated. After repeating such a pattern for 8 slots, two slots without SSB are placed. By repeating such a pattern, 64 transmission candidate positions of the SSB are set.

[0071] FIG. 9 is a diagram showing Example 1-2 of the SSB transmission candidate positions in a slot. In the example of FIG. 9, the configuration of Case E shown in FIG. 5 is reused. The number of symbols per slot may be 28. For example, 240 kHz, 480 kHz, and 960 kHz may be supported as the SCS of the SSB and the SCS of the PDCCH / PDSCH. In the example of FIG. 9, even when 240 kHz, 480 kHz, and 960 kHz are supported as the SCS of the SSB and the SCS of the PDCCH / PDSCH, the configuration of Case E shown in FIG. 5 is applied. In the example of FIG. 9, when the SCS is 240 kHz, the slot length is 0.125 ms; when the SCS is 480 kHz, the slot length is 0.0625 ms; and when the SCS is 960 kHz, the slot length is 0.03125 ms. In the example of FIG. 9, four SSBs are mapped to be adjacent in a slot. Between two consecutive slots, a pattern in which SSBs are not mapped to the first 8 symbols and the last 4 symbols and a pattern in which SSBs are not mapped to the first 4 symbols and the last 8 symbols are alternately repeated. After repeating such a pattern for eight slots, two slots without SSBs are placed. By repeating such a pattern, 64 transmission candidate positions of SSBs are set.

[0072] FIG. 10 is a diagram showing Examples 1-3 of SSB transmission candidate positions in a slot. In the example of FIG. 10, it is an example in which the configuration of Case D shown in FIG. 4 is applied when the number of symbols per slot is 28. For example, 240 kHz, 480 kHz, and 960 kHz may be supported as the SCS of the SSB and the SCS of the PDCCH / PDSCH. In the example of FIG. 10, when the SCS is 240 kHz, the slot length is 0.125 ms, when the SCS is 480 kHz, the slot length is 0.0625 ms, and when the SCS is 960 kHz, the slot length is 0.03125 ms. In the example of FIG. 10, within one slot, SSB is not mapped to the first 4 symbols, the first SSB is mapped to the subsequent 4 symbols, the second SSB is mapped to the subsequent 4 symbols, SSB is not mapped to the subsequent 4 symbols, the third SSB is mapped to the subsequent 4 symbols, the fourth SSB is mapped to the subsequent 4 symbols, and SSB is not mapped to the subsequent 4 symbols.

[0073] In Example 1-3-1 shown in FIG. 10, after 4 consecutive slots in which the SSB transmission candidate positions are mapped as described above, a pattern in which 1 slot where the SSB transmission candidate position is not mapped is placed is repeated, and 64 SSB transmission candidate positions are set.

[0074] In Example 1-3-2 shown in FIG. 10, after 8 consecutive slots in which the SSB transmission candidate positions are mapped as described above, a pattern in which 2 slots where the SSB transmission candidate position is not mapped are placed is repeated, and 64 SSB transmission candidate positions are set.

[0075] Also, as Example 1-4, the configuration of Case C shown in FIG. 7 may be applied when the number of symbols per slot is 14.

[0076] Also, as Example 1-5, the configuration of Case C shown in FIG. 7 may be applied when the number of symbols per slot is 28.

[0077] Also, as Example 1-6, any of the configurations of Example 1-1 to Example 1-5 above may be applied for each SCS. For example, when the SCS is 240 kHz, Example 1-1 or Example 1-4 (when the number of symbols per slot is 14) may be applied. Also, for example, when the SCS is 480 kHz or 960 kHz, Example 1-2, Example 1-3, or Example 1-4 (when the number of symbols per slot is 28) may be applied.

[0078] (Option 2) The combination of the SCS of the SSB and the SCS of the PDCCH / PDSCH may be limited to 1) the case where the SCS of the SSB and the SCS of the PDCCH / PDSCH are the same, and / or 2) the case where the SCS of the SSB is twice the SCS of the PDCCH / PDSCH. Note that this embodiment is not limited to the case where the SCS of the SSB is twice the SCS of the PDCCH / PDSCH. For example, the SCS of the SSB may be 1 / 2 times, 3 / 2 times, or 3 times the SCS of the PDCCH / PDSCH.

[0079] FIG. 11 is a diagram showing Example 2-1 of the SSB transmission candidate positions in a slot. In the example of FIG. 11, the configuration of Case D shown in FIG. 4 is reused. The number of symbols per slot may be 14. For example, as the SCS of PDCCH / PDSCH, 120 kHz, 240 kHz, and 480 kHz may be supported, and as the corresponding SCS of SSB, 240 kHz, 480 kHz, and 960 kHz may be supported. In the example of FIG. 11, when the SCS is 240 kHz, the slot length is 0.0625 ms, when the SCS is 480 kHz, the slot length is 0.03125 ms, and when the SCS is 960 kHz, the slot length is 0.01526 ms. In the example of FIG. 11, two SSBs are mapped to be adjacent in the slot. Between two consecutive slots, a pattern in which SSBs are not mapped to the first 4 symbols and the last 2 symbols and a pattern in which SSBs are not mapped to the first 2 symbols and the last 4 symbols are alternately repeated. After repeating such a pattern for 8 slots, two slots without SSBs are placed. By repeating such a pattern, 64 SSB transmission candidate positions are set.

[0080] Figure 12 is a diagram showing Example 2-2 of the SSB transmission candidate positions within a slot. In the example of Figure 12, the configuration of Case E shown in Figure 5 is reused. The number of symbols per slot may be 14. For example, as the SCS of PDCCH / PDSCH, 120 kHz, 240 kHz, and 480 kHz may be supported, and as the corresponding SCS of the SSB, 240 kHz, 480 kHz, and 960 kHz may be supported. In the example of Figure 12, when the SCS of the SSB is 240 kHz, the slot length is 0.125 ms; when the SCS of the SSB is 480 kHz, the slot length is 0.0625 ms; and when the SCS of the SSB is 960 kHz, the slot length is 0.03125 ms. In the example of Figure 12, four SSBs are mapped to be adjacent within the slot. Between two consecutive slots, a pattern where SSBs are not mapped to the first 8 symbols and the last 4 symbols, and a pattern where SSBs are not mapped to the first 4 symbols and the last 8 symbols are alternately repeated. After repeating such a pattern for 8 slots, two slots without SSBs are placed. By repeating such a pattern, 64 SSB transmission candidate positions are set.

[0081] Also, as Example 2-3, the configuration of Case D shown in Figure 4 may be applied when the number of symbols per slot is 28.

[0082] Also, as Example 2-4, the configuration of Case E shown in Figure 5 may be applied when the number of symbols per slot is 28.

[0083] Also, as Example 2-5, the configuration of Case C shown in Figure 7 may be applied when the number of symbols per slot is 14.

[0084] Also, as Example 2-5, the configuration of Case C shown in Figure 7 may be applied when the number of symbols per slot is 28.

[0085] Also, as Example 2-7, any of the configurations from Example 2-1 to Example 2-6 described above may be applied for each SCS. For example, when the SCS of the SSB is 240 kHz, Example 2-1, Example 2-2, or Example 2-5 (when the number of symbols per slot is 14) may be applied. Also, for example, when the SCS of the SSB is 480 kHz or 960 kHz, Example 2-3, Example 2-4, or Example 2-6 (when the number of symbols per slot is 28) may be applied.

[0086] (Option 3) For different SCSs, different options among the above Option 1 and Option 2 may be applied. For example, when the SCS of the SSB is 240 kHz, Option 1 (when the SCS of the SSB and the SCS of the PDCCH / PDSCH are the same) may be applied, and when the SCS of the SSB is 480 kHz or 960 kHz, Option 2 (when the SCS of the SSB is twice that of the PDCCH / PDSCH) may be applied.

[0087] (Regarding the unlicensed frequency band included in the frequency band from 52.6 GHz to 71 GHz) In the unlicensed frequency band included in the frequency band from 52.6 GHz to 71 GHz, the terminal 10 and / or the base station 20 may perform Listen Before Talk (LBT), that is, perform carrier sense before starting transmission and perform transmission within a predetermined time length only when it is confirmed that the channel is not being used by other nearby systems.

[0088] In the operation of the unlicensed frequency band included in the frequency band from 52.6 GHz to 71 GHz, the index of the transmission candidate position of the SSB may be from 0 to 63, and the index of the transmission candidate position of the SSB may also be derivable from the PBCH DMRS sequence and the payload of the PBCH, similar to the case of FR2 of NR in Release 15.

[0089] In the case of operating an unlicensed frequency band included in the frequency band from 52.6 GHz to 71 GHz, the transmission candidate positions of SSBs in a slot may be based on the configuration of Case C shown in FIG. 7, the configuration of Case D shown in FIG. 4, or the configuration of Case E shown in FIG. 5 (it may be the same as or different from the configuration in the case of a licensed frequency band included in the frequency band from 52.6 GHz to 71 GHz).

[0090] In the case of operating an unlicensed frequency band included in the frequency band from 52.6 GHz to 71 GHz, the mapping of a slot including the transmission candidate position of an SSB may be different from the mapping of a slot including the transmission candidate position of an SSB in the case of operating a licensed frequency band included in the frequency band from 52.6 GHz to 71 GHz.

[0091] FIG. 13 is a diagram showing an example of the mapping of a slot including the transmission candidate position of an SSB in an unlicensed frequency band included in the frequency band from 52.6 GHz to 71 GHz. As shown in FIG. 13, slots including the transmission candidate position of an SSB may be arranged continuously. That is, slots not including the transmission candidate position of an SSB may not be included. As shown in FIG. 13, the number of symbols per slot may be 14. In this way, by arranging slots including the transmission candidate position of an SSB continuously, it is possible to prevent the need to perform Listen Before Talk (LBT) again due to the presence of slots not including the transmission candidate position of an SSB.

[0092] FIG. 14 is a diagram showing another example of the mapping of a slot including the transmission candidate position of an SSB in an unlicensed frequency band included in the frequency band from 52.6 GHz to 71 GHz. As shown in FIG. 14, slots including the transmission candidate position of an SSB may be arranged continuously. That is, slots not including the transmission candidate position of an SSB may not be included. As shown in FIG. 14, the number of symbols per slot may be 28.

[0093] The 3 LSBs of the index of the SSB transmission candidate positions may be indicated by the PBCH DMRS sequence.

[0094] The 3 MSBs of the index of the SSB transmission candidate positions may be indicated by the PBCH payload.

[0095] In NR-U, the slot containing the SSB transmission candidate position is defined within 5 ms. Separately, a discovery burst transmission window is included as a serving cell setting. The length of the discovery burst transmission window is selected from 0.5 ms, 1 ms, 2 ms, 3 ms, 4 ms, 5 ms. For example, when the number of beams is small, by setting a shorter discovery burst transmission window instead of 5 ms as the length of the discovery burst transmission window, it is possible to reduce the load on the terminal 10. This discovery burst transmission window is also assumed to be required in the unlicensed frequency band included in the frequency band from 52.6 GHz to 71 GHz. For example, the maximum time length that can be set as the discovery burst transmission window in the unlicensed frequency band included in the frequency band from 52.6 GHz to 71 GHz may be shorter than 5 ms. For example, when the SCS is 240 kHz, the maximum time length that can be set as the discovery burst transmission window may be 2 ms. Also, a discovery burst transmission window with a length shorter than 0.5 ms (for example, 0.25 ms) may be introduced for a larger SCS. Also, a granularity of the length of the discovery burst transmission window smaller than 1 ms (for example, 1.5 ms) may be introduced.

[0096] As described above, in the unlicensed frequency band included in the frequency band from 52.6 GHz to 71 GHz, a plurality of SSB transmission candidate positions may be set for each SSB beam.

[0097] In the case of operating in the unlicensed frequency band included in the frequency band from 52.6 GHz to 71 GHz, the index of the SSB may be from 0 to 63, and the index of the SSB may be derivable from the index of the SSB transmission candidate position and the QCL parameter in the PBCH payload.

[0098] FIG. 15 is a diagram showing an example of deriving the SSB index based on the SSB candidate position and the QCL parameter. For example, when the value of the QCL parameter is 64, the SSB index and the SSB candidate position may coincide.

[0099] The QCL parameter may be selected from a set of candidate values such as {8, 16, 32, 64}, for example. In terms of reusing the NR-U design, it is preferable to use 2 bits (up to 4 candidate values). Alternatively, the number of candidate values of the QCL parameter may be different from other frequency bands (for example, it may be less than or more than 4, the number of candidate values in the NR-U frequency band). For example, when the number of candidate values is small, the number of bits required for notification can be reduced.

[0100] The QCL parameter may be transmitted by the MIB, SIB1, or both the MIB and SIB1. When the QCL parameter is transmitted by SIB1, the terminal 10 may assume a default QCL parameter (for example, 64) before receiving SIB1.

[0101] The terminal 10 may assume that the number of SSBs actually transmitted in the discovery burst transmission window is less than or equal to the QCL parameter value (it may be assumed that the number of SSBs is the same as the QCL parameter value, or it may be assumed that the number of SSBs is less than the QCL parameter value).

[0102] The terminal 10 may assume that the SCS of the SSB is the same as that of the SIB1 PDCCH / PDSCH (or it may assume that the SCS of the SSB is twice that of the SCS of the SIB1 PDCCH / PDSCH). The value range of k_SSB, which is a parameter for notifying the deviation value between the PRB of the SSB and the common PRB where data and the like are transmitted, may be from 0 to 11, and may be notified by ssb-SubcarrierOffset of the MIB.

[0103] The PBCH payload may be, for example, 8 bits in total, including the 4 LSBs of the SFN, the Half-frame bit, and the 3 MSBs of the index of the SSB transmission candidate position, outside the MIB.

[0104] The PBCH payload may be, for example, inside the MIB, the 6 MSBs of the SFN, SSB-SubcarrierOffset (4 bits), dmrs-TypeA-Position (1 bit), pdcch-ConfigSIB1 (8 bits), cellBarred (1 bit), intraFreqReselection (1 bit), subCarrierSpacingCommon (1 bit), and spare (1 bit).

[0105] The QCL parameter (for example, 2 bits) may be transmitted by any of the following.

[0106] (Alt.1) subCarrierSpacingCommon (when the SCS is the same) + spare bit

[0107] (Alt.2) dmrs-TypeA-Position (when one DMRS type A position is supported) + spare bit

[0108] (Alt.3) Part of pdcch-ConfigAIB1 (+ spare bit)

[0109] (Alt.4) cellBarred + intraFreqReselection (when only access other than stand-alone is supported)

[0110] Any combination of Alt.1 to Alt.4 above.

[0111] Regarding ssb-PositionsInBurst in SIB1 / RRC, it may be a 64-bit bitmap, and the number of "1"s included in ssb-PositionsInBurst may be less than or equal to the value of the QCL parameter.

[0112] (Device configuration) Next, a functional configuration example of the terminal 10 and the base station 20 that execute the processing operations described so far will be described. The terminal 10 and the base station 20 have all the functions described in this embodiment. However, the terminal 10 and the base station 20 may have only some of the functions described in this embodiment. Note that the terminal 10 and the base station 20 may be collectively referred to as a communication device.

[0113] <Terminal> FIG. 16 is a diagram showing an example of the functional configuration of the terminal 10. As shown in FIG. 16, the terminal 10 includes a transmission unit 110, a reception unit 120, and a control unit 130. The functional configuration shown in FIG. 16 is merely an example. As long as the operations according to this embodiment can be executed, the functional division and the names of the functional units may be any. Note that the transmission unit 110 may be referred to as a transmitter, and the reception unit 120 may be referred to as a receiver.

[0114] The transmission unit 110 creates a transmission from the transmission data and wirelessly transmits the transmission signal. In addition, the transmission unit 110 can form one or more beams. The reception unit 120 wirelessly receives various signals and acquires signals of higher layers from the received physical layer signals. In addition, the reception unit 120 includes a measurement unit that measures the received signals to acquire received power and the like.

[0115] The control unit 130 controls the terminal 10. Note that the function of the control unit 130 related to transmission may be included in the transmission unit 110, and the function of the control unit 130 related to reception may be included in the reception unit 120.

[0116] For example, the reception unit 120 receives a synchronization signal block (SSB) transmitted from the base station 20 in an unlicensed frequency band included in the frequency band from 52.6 GHz to 71 GHz, and the control unit 130 may derive a transmission candidate position of the SSB based on a sequence of demodulation reference signals (DMRS) of the physical broadcast channel (PBCH) and the payload of the PBCH. Further, the control unit 130 may assume that the index of the SSB takes any value from 0 to 63, and derive it from the transmission candidate position of the SSB and the Quasi co-location (QCL) parameters in the PBCH payload.

[0117] For example, the control unit 130 may assume that slots including the transmission candidate position of the SSB are arranged continuously in an unlicensed frequency band included in the frequency band from 52.6 GHz to 71 GHz.

[0118] <Base station 20> FIG. 17 is a diagram showing an example of the functional configuration of the base station 20. As shown in FIG. 17, the base station 20 includes a transmission unit 210, a reception unit 220, and a control unit 230. The functional configuration shown in FIG. 17 is merely an example. As long as the operations according to the present embodiment can be executed, the function division and the names of the functional units may be any. Note that the transmission unit 210 may be referred to as a transmitter, and the reception unit 220 may be referred to as a receiver.

[0119] The transmission unit 210 includes a function of generating a signal to be transmitted to the terminal 10 side and wirelessly transmitting the signal. The reception unit 220 includes a function of receiving various signals transmitted from the terminal 10 and obtaining information of a higher layer, for example, from the received signals. Further, the reception unit 220 includes a measurement unit that measures the received signal to obtain the received power and the like.

[0120] The control unit 230 controls the base station 20. Note that the functions of the control unit 230 related to transmission may be included in the transmission unit 210, and the functions of the control unit 230 related to reception may be included in the reception unit 220.

[0121] In the unlicensed frequency band included in the frequency band from 52.6 GHz to 71 GHz, the control unit 230 sets a sequence of demodulation reference signals (DMRS) for a physical broadcast channel (PBCH) corresponding to the transmission candidate position of the SSB and the payload of the PBCH, and the transmission unit 210 may transmit a synchronization signal block (SSB) including the set DMRS sequence of the PBCH and the payload of the PBCH. Also, the control unit 230 may select an SSB index of any value from 0 to 63 and transmit the SSB at the transmission position and beam corresponding to the SSB index.

[0122] For example, in the unlicensed frequency band included in the frequency band from 52.6 GHz to 71 GHz, the control unit 230 may continuously arrange slots including the transmission candidate position of the SSB.

[0123] <Hardware Configuration> The block diagrams (Figs. 16 to 17) used in the description of the above embodiments show blocks in terms of functions. These functional blocks (components) are realized by any combination of hardware and / or software. Also, the means for realizing each functional block is not particularly limited. That is, each functional block may be realized by one device in which a plurality of elements are physically and / or logically combined, or may be realized by two or more physically and / or logically separated devices directly and / or indirectly (e.g., wired and / or wirelessly) connected.

[0124] Further, for example, both the terminal 10 and the base station 20 in one embodiment of the present invention may function as a computer that performs the processing according to this embodiment. FIG. 18 is a diagram showing an example of the hardware configuration of the terminal 10 and the base station 20 according to this embodiment. Physically, the above-described terminal 10 and base station 20 may each be 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.

[0125] In the following description, the term "device" can be read as a circuit, a device, a unit, etc. The hardware configuration of the terminal 10 and the base station 20 may be configured to include one or more of each device indicated by 1001 to 1006 shown in the figure, or may be configured without including some devices.

[0126] Each function in the terminal 10 and the base station 20 is realized by causing the processor 1001 to load a predetermined software (program) onto hardware such as the processor 1001 and the memory 1002, so that the processor 1001 performs calculations and controls communication by the communication device 1004 and reading and / or writing of data in the memory 1002 and the storage 1003.

[0127] The processor 1001 controls the entire computer by operating an operating system, for example. The processor 1001 may be composed of a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic device, a register, and the like.

[0128] Also, the processor 1001 reads a program (program code), software module, or data from the storage 1003 and / or the communication device 1004 into 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 operations described in the above embodiments is used. For example, the transmission unit 110, reception unit 120, and control unit 130 of the terminal 10 shown in FIG. 16 may be stored in the memory 1002 and realized by a control program operating on the processor 1001. Also, for example, the transmission unit 210, reception unit 220, and control unit 230 of the base station 20 shown in FIG. 17 may be stored in the memory 1002 and realized by a control program operating on the processor 1001. Although it has been described that the above various processes are executed by one processor 1001, they may be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 may be implemented with one or more chips. Note that the program may be transmitted from a network via a telecommunication line.

[0129] The memory 1002 is a computer-readable recording medium and may be composed of at least one of, for example, ROM (Read Only Memory), EPROM (Erasable Programmable ROM), EEPROM (Electrically Erasable Programmable ROM), RAM (Random Access Memory), etc. The memory 1002 may be referred to as a register, cache, main memory (main storage device), etc. The memory 1002 can store a program (program code), software module, etc. that is executable to perform the processes according to an embodiment of the present invention.

[0130] Storage 1003 is a computer-readable recording medium and may be composed of, for example, at least one of an optical disc such as a CD-ROM (Compact Disc ROM), a hard disk drive, a flexible disk, a magneto-optical disk (e.g., a compact disc, a digital versatile disc, a Blu-ray (registered trademark) disc), a smart card, a flash memory (e.g., a card, a stick, a key drive), a floppy (registered trademark) disk, a magnetic strip, etc. Storage 1003 may be referred to as an auxiliary storage device. The above-described storage medium may be, for example, a database including memory 1002 and / or storage 1003, a server, or other appropriate media.

[0131] Communication device 1004 is hardware (a transmission / reception device) for performing communication between computers via a wired and / or wireless network and is also referred to as, for example, a network device, a network controller, a network card, a communication module, etc. For example, the transmission unit 110 and the reception unit 120 of terminal 10 may be realized by communication device 1004. Also, the transmission unit 210 and the reception unit 220 of base station 20 may be realized by communication device 1004.

[0132] Input device 1005 is an input device (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) for receiving an external input. Output device 1006 is an output device (e.g., a display, a speaker, an LED lamp, etc.) for performing an output to the outside. Note that input device 1005 and output device 1006 may have an integrated configuration (e.g., a touch panel).

[0133] Also, each device such as processor 1001 and memory 1002 is connected by a bus 1007 for communicating information. Bus 1007 may be composed of a single bus or may be composed of different buses between devices.

[0134] Further, the terminal 10 and the base station 20 may each be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA), and some or all of the functional blocks may be realized by the hardware. For example, the processor 1001 may be implemented by at least one of these hardware components.

[0135] (Summary of Embodiment) This specification discloses at least the following terminal and base station.

[0136] A terminal comprising: a receiving unit that receives a synchronization signal block in an unlicensed band of a high frequency band equal to or higher than the frequency band of Frequency Range 2 (FR2) among the low frequency band of Frequency Range 1 (FR1) and the high frequency band of Frequency Range 2 (FR2) of a New Radio (NR) system; and a control unit that specifies an index of a transmission candidate position of the synchronization signal block based on a sequence of demodulation reference signals of a notification channel included in the synchronization signal block and a payload of the notification channel.

[0137] According to the above configuration, the terminal can specify the index of the transmission candidate position of the synchronization signal block in the unlicensed band of the high frequency band equal to or higher than Frequency Range 2, which is the second frequency band of the NR system.

[0138] The control unit may assume that the number of continuously arranged slots including the transmission candidate position of the synchronization signal block is greater than 8.

[0139] According to the above configuration, in the unlicensed band of a frequency band higher than Frequency Range2, which is the second frequency band of the New Radio (NR) system, it is possible to apply LBT and continuously transmit a plurality of synchronization signal blocks.

[0140] The control unit may specify the index of the synchronization signal block based on the transmission candidate position of the synchronization signal block and the Quasi co-location (QCL) parameters included in the notification channel.

[0141] According to the above configuration, the terminal can specify the index of the synchronization signal block by receiving the synchronization signal block.

[0142] The control unit may assume that the time length of the discovery burst transmission window set in the unlicensed band is shorter than the time length of the discovery burst transmission window set in the FR1.

[0143] According to the above configuration, the burden on the terminal when specifying the transmission candidate position of the SSB is reduced.

[0144] A base station comprising: a control unit that sets a sequence of demodulation reference signals for a notification channel and a payload of the notification channel, which are associated with the transmission candidate position of a synchronization signal block transmitted in an unlicensed band of a high frequency band equal to or higher than the frequency band of the FR2, among the Frequency Range1 (FR1), which is the low frequency band of the New Radio (NR) system, and the Frequency Range2 (FR2), which is the high frequency band; and a transmission unit that transmits the synchronization signal block including the set sequence of demodulation reference signals for the notification channel and the payload of the notification channel.

[0145] According to the above configuration, the base station can notify the terminal of the transmission candidate positions of the synchronization signal blocks in the unlicensed band of a high-frequency band of Frequency Range 2 or higher, which is the second frequency band of the NR system.

[0146] (Supplement to the embodiment) As described above, the embodiments of the present invention have been described. However, the disclosed invention is not limited to such embodiments, and those skilled in the art will understand various variations, modifications, alternatives, substitutions, etc. Although specific numerical examples have been used for explanation to facilitate understanding of the invention, unless otherwise specified, those numerical values are merely examples, and any appropriate values may be used. The classification of items in the above description is not essential to the present invention, and the matters described in two or more items may be used in combination as needed, or the matters described in one item may be applied to the matters described in another item (as long as there is no contradiction). The boundaries of the 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 units may be physically performed by one component, or the operation of one functional unit 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. For the convenience of explaining the processing, the terminal 10 and the base station 20 have been described using a functional block diagram, but such devices may be realized by hardware, software, or a combination thereof. The software operated by the processor included in the terminal 10 according to the embodiment of the present invention and the software operated by the processor included in the base station 20 according to the embodiment of the present invention may be stored in any appropriate storage media such as random access memory (RAM), flash memory, read-only memory (ROM), EPROM, EEPROM, register, hard disk drive (HDD), removable disk, CD-ROM, database, server, and others.

[0147] The notification of information is not limited to the aspects / embodiments described in this specification and may be performed in other ways. For example, the notification of information may be implemented by physical layer signaling (e.g., DCI (Downlink Control Information), UCI (Uplink Control Information)), upper layer signaling (e.g., RRC (Radio Resource Control) signaling, MAC (Medium Access Control) signaling, broadcast information (MIB (Master Information Block), SIB (System Information Block)), other signals or combinations thereof. Also, the RRC signaling may be referred to as an RRC message and may be, for example, an RRC Connection Setup message, an RRC Connection Reconfiguration message, etc.

[0148] Each aspect / embodiment described in this specification may be applicable to systems that utilize LTE (Long Term Evolution), LTE-A (LTE-Advanced), SUPER 3G, IMT-Advanced, 4G, 5G, FRA (Future Radio Access), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, UWB (Ultra-WideBand), Bluetooth (registered trademark), other suitable systems and / or next-generation systems extended based thereon.

[0149] The processing procedures, sequences, flowcharts, etc. of each aspect / embodiment described in this specification may be reordered as long as there is no contradiction. For example, for the methods described in this specification, the elements of various steps are presented in an exemplary order and are not limited to the specific order presented.

[0150] The specific operations assumed to be performed by the base station 20 in this specification may, in some cases, be performed by its upper node. In a network consisting of one or more network nodes having the base station 20, various operations performed for communication with the terminal 10 can clearly be performed by the base station 20 and / or other network nodes other than the base station 20 (for example, but not limited to, MME or S-GW, etc.). Although the case where there is one other network node other than the base station 20 was exemplified above, a combination of a plurality of other network nodes (for example, MME and S-GW) may also be possible.

[0151] Each aspect / embodiment described in this specification may be used alone, in combination, or switched and used during execution.

[0152] The terminal 10 may also be referred to by those skilled in the art as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other appropriate term.

[0153] The base station 20 may also be referred to by those skilled in the art as an NB (NodeB), eNB (enhanced NodeB), Base Station, gNB, or some other appropriate term.

[0154] A bandwidth part (BWP, which may also be referred to as a partial bandwidth, etc.) may represent a subset of consecutive common resource blocks (RB) for a certain numerology in a certain carrier. Here, the common RB may be identified by the index of the RB based on the common reference point of the carrier. A PRB may be defined in a certain BWP and numbered within that BWP.

[0155] The BWP may include a BWP for UL (UL BWP) and a BWP for DL (DL BWP). One or more BWPs may be configured for a UE within one carrier.

[0156] At least one of the configured BWPs may be active, and the UE may not be assumed to transmit and receive a predetermined signal / channel outside the active BWP. Note that "cell", "carrier", etc. in the present disclosure may be read as "BWP".

[0157] As used herein, the terms "determining" and "deciding" may encompass a wide variety of operations. "Determining" and "deciding" may include, for example, judging, calculating, computing, processing, deriving, investigating, looking up (e.g., looking up in a table, database, or another data structure), and deeming something as having been "determined" or "decided" based on what has been ascertained. Further, "determining" and "deciding" may include deeming something as having been "determined" or "decided" based on what has been received (e.g., receiving information), transmitted (e.g., transmitting information), input, output, or accessed (e.g., accessing data in a memory). Additionally, "determining" and "deciding" may include deeming something as having been "determined" or "decided" based on what has been resolved, selected, chosen, established, or compared. That is, "determining" and "deciding" may include deeming that some operation has been "determined" or "decided".

[0158] As used herein, the phrase "based on" does not mean "based only on" unless otherwise specified. In other words, the phrase "based on" means both "based only on" and "based at least in part on".

[0159] As long as the terms "include", "including", and their variants are used in this specification or in the claims, these terms are intended to be inclusive in the same manner as the term "comprising". Further, the term "or" as used in this specification or in the claims is not intended to be exclusive disjunction.

[0160] Throughout the present disclosure, for example, when articles are added by translation such as a, an, and the in English, these articles may include plural ones unless the context clearly indicates otherwise.

[0161] As described above in detail with respect to the present invention, it is obvious to those skilled in the art that the present invention is not limited to the embodiments described in this specification. The present invention can be implemented in modified and changed forms without departing from the spirit and scope of the present invention as defined by the claims. Therefore, the description in this specification is for illustrative purposes and has no restrictive meaning for the present invention.

Explanation of Reference Signs

[0162] 10 Terminal 110 Transmitter 120 Receiver 130 Control Unit 20 Base Station 210 Transmitter 220 Receiver 230 Control Unit 1001 Processor 1002 Memory 1003 Storage 1004 Communication Device 1005 Input Device 1006 Output Device

Claims

1. A terminal in a wireless communication system that communicates in a first frequency band and a second frequency band having a frequency higher than the first frequency band, a receiving unit that receives first setting information including QCL (Quasi co-location) parameters selected from a number of candidates less than the number of candidates used in the first frequency band, regarding reception of a synchronization signal block in the second frequency band, and second setting information capable of setting a discovery reverse transmission window length having a maximum value and a minimum value smaller than the discovery reverse transmission window length in the first frequency band and a finer granularity; a control unit that sets the QCL parameters based on the first setting information and sets the discovery reverse transmission window length based on the second setting information; comprising: The receiving unit is a terminal that assumes receiving the synchronization signal blocks within the discovery reverse transmission window whose number is less than or equal to the value of the QCL parameters set by the control unit.

2. The terminal according to claim 1, wherein the receiving unit receives the QCL parameters transmitted by subCarrierSpacingCommon in a MIB (Master Information Block).

3. A base station in a wireless communication system that communicates in a first frequency band and a second frequency band having a frequency higher than the first frequency band, a transmitting unit that transmits first setting information including QCL (Quasi co-location) parameters selected from a number of candidates less than the number of candidates used in the first frequency band, regarding reception of a synchronization signal block in the second frequency band, and second setting information capable of setting a discovery reverse transmission window length having a maximum value and a minimum value smaller than the discovery reverse transmission window length in the first frequency band and a finer granularity; a control unit that sets the QCL parameters based on the first setting information and sets the discovery reverse transmission window based on the second setting information; comprising: The transmitting unit is a base station that transmits the synchronization signal blocks within the discovery reverse transmission window whose number is less than or equal to the value of the QCL parameters set by the control unit.

4. A wireless communication system that communicates in a first frequency band and a second frequency band having a frequency higher than the first frequency band, First configuration information including a QCL (Quasi co-location) parameter selected from a number of candidates less than that used in the first frequency band, regarding reception of a synchronization signal block in the second frequency band, and a transmission unit that transmits to a terminal second configuration information capable of setting a length of a discovery reverse transmission window having a maximum value and a minimum value smaller than that of the discovery reverse transmission window in the first frequency band and having a fine granularity, a control unit that sets the QCL parameter based on the first configuration information and sets the discovery reverse transmission window based on the second configuration information, comprising, the transmission unit is a base station that transmits to the terminal the synchronization signal blocks having a number equal to or less than the value of the QCL parameter set by the control unit within the discovery reverse transmission window, a receiving unit that receives the first configuration information and the second configuration information from the base station, regarding reception of a synchronization signal block in the second frequency band, a control unit that sets the QCL parameter based on the first configuration information and sets the discovery reverse transmission window based on the second configuration information, comprising, the receiving unit is a terminal assuming that it receives the synchronization signal blocks having a number equal to or less than the value of the QCL parameter set by the control unit within the discovery reverse transmission window, a communication system comprising. **Claim 5** A communication method executed by a terminal in a wireless communication system that communicates in a first frequency band and a second frequency band having a frequency higher than the first frequency band, a receiving step of receiving first configuration information including a QCL (Quasi co-location) parameter selected from a number of candidates less than that used in the first frequency band, regarding reception of a synchronization signal block in the second frequency band, and second configuration information capable of setting a length of a discovery reverse transmission window having a maximum value and a minimum value smaller than that of the discovery reverse transmission window in the first frequency band and having a fine granularity, a control step of setting the QCL parameter based on the first configuration information and setting the discovery reverse transmission window based on the second configuration information, comprising. The receiving step is a communication method assuming that, within the discovery reverse transmission window, the synchronization signal blocks in a number equal to or less than the value of the QCL parameter set by the control step are received.

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