Patent Description:
In the UMTS (Universal Mobile Telecommunications System) network, the specifications of long-term evolution (LTE) have been drafted for the purpose of further increasing high speed data rates, providing lower latency and so on (see non-patent literature <NUM>). Also, the specifications of LTE-A (also referred to as "LTE-advanced," "LTE Rel. <NUM>," "LTE Rel. <NUM>," or "LTE Rel. <NUM>") have been drafted to provide widebands and increased speed beyond LTE (also referred to as "LTE Rel. <NUM>" or "LTE Rel. <NUM>"), and successor systems of LTE (also referred to as, for example, "FRA (Future Radio Access)," "<NUM> (5th generation mobile communication system)," "NR (New Radio)," "NX (New radio access)," "FX (Future generation radio access)," "LTE Rel. <NUM>," "LTE Rel. <NUM>," "LTE Rel. <NUM>" or later versions) are under study.

In LTE Rel. <NUM>/<NUM>, carrier aggregation (CA) to integrate multiple component carriers (CC) is introduced in order to achieve broadbandization. Each CC is configured with the system bandwidth of LTE Rel. <NUM> as <NUM> unit. Furthermore, in CA, a number of CCs under the same radio base station (referred to as, for example, "eNB (evolved Node B)," "BS (Base Station)," and so on) are configured in a user terminal (UE (User Equipment)).

Meanwhile, in LTE Rel. <NUM>, dual connectivity (DC), in which multiple cell groups (CGs) formed with different radio base stations are configured in UE, is also introduced. Each cell group is comprised of at least <NUM> cell (CC). Given that multiple CCs of varying radio base stations are integrated in DC, DC is also referred to as "inter-eNB CA.

Also, in LTE Rel. <NUM> to <NUM>, frequency division duplexing (FDD), in which downlink (DL) transmission and uplink (UL) transmission take place in different frequency bands, and time division duplexing (TDD), in which downlink transmission and uplink transmission switch over time and take place in the same frequency band, are introduced.

Non-Patent Literature <NUM> relates to synchronization signal bandwidth and multiplexing consideration.

Non-Patent Literature <NUM> relates to Physical Broadcast Channel design and to high-level synchronization design for NR.

Non-Patent Literature <NUM> relates to wide bandwidths operations for NR.

Non-Patent Literature <NUM> relates a synchronization signal raster for NR and to details on the sync raster and numerology for synchronization signals in NR.

Future radio communication systems (for example, <NUM>, NR, etc.) are expected to realize various radio communication services so as to fulfill mutually varying requirements (for example, ultra high speed, large capacity, ultra-low latency, etc.).

For example, <NUM>/NR is under study to provide radio communication services, referred to as "eMBB (enhanced Mobile Broad Band)," "mMTC (massive Machine Type Communication)," "URLLC (Ultra Reliable and Low Latency Communications)," and so on.

Also, <NUM>/NR is expected to support different frequencies and different bandwidths. Given these frequencies, the problem then lies in how to efficiently operate user terminals with various capabilities.

The present invention has been made in view of the above, and it is there an object of the present invention to provide a user terminal and a radio communication method, whereby frequency bands can be used efficiently depending on what capabilities a user terminal has.

According to the present invention, frequency bands can be used efficiently depending on what capabilities a user terminal has.

Envisaging NR, studies are in progress to support bandwidth up to <NUM> in frequency bands higher than <NUM> and support bandwidth up to <NUM> in frequency bands lower than <NUM>, for the purpose of expanding bandwidth.

Even if the NW (for example, a base station, a gNB, etc.) supports such bandwidths, UE may have a limited bandwidth in CC depending on its RF (Radio Frequency) and/or baseband-related capabilities.

<FIG> is a diagram to show examples of RF chains. A frequency band that can be used for a channel in NR is referred to as a "channel band. " The NW processes a channel band using <NUM> RF chain (for example, transmitting/receiving sections, an RF processing section, etc.). UE #<NUM> can process a channel band using <NUM> RF chain. UE #<NUM> can process a channel band using <NUM> RF chains. Each <NUM> RF chain can process half the bandwidth of the channel band. The baseband signal processing section of UE #<NUM> may process each RF chain's band as a CC and process <NUM> CCs, or the baseband signal processing section of UE #<NUM> may process the bands of the <NUM> RF chains together as <NUM> CC.

The RF chain-related capabilities of each UE may be represented by UE capabilities.

<FIG> are diagrams to show examples of frequency bands for use for UEs having different UE capabilities. A UE that can process a channel band by using <NUM> RF chain is referred to as a "wideband UE," and a UE that can process a channel band by using <NUM> RF chain due to RF-related capability limitations and the like is referred to as a "narrowband UE.

As shown in <FIG>, wideband UE #<NUM> runs CA to use a CC having a <NUM>-MHz bandwidth and a CC having a <NUM>-MHz bandwidth in a channel band having a <NUM>-MHz bandwidth. In this case, a guard band may be provided between the <NUM> CCs. The narrowband UE processes <NUM> CC having a bandwidth narrower than <NUM>.

As shown in <FIG>, wideband UE #<NUM> processes a channel band as <NUM> CC.

The NW may operate using a wideband CC for some UEs, and, at the same time, for other UEs, the NW may run CA by using a set of multiple contiguous CCs (intra-band contiguous CCs) in the band of the wideband CC. Each CC in the set of multiple CCs may be referred to as a "narrowband CC. " A wideband CC may be a CC to span a channel band, or may be a CC to span a wider band than a narrowband CC.

<FIG> is a diagram to show examples of UE capabilities. The channel band is, for example, <NUM>. The NW can process the whole channel band. A band that can be processed by the NW is referred to as a "NW channel band.

In this example, UEs #<NUM>, #<NUM> and #<NUM>, having different UE capabilities, co-exist.

UE #<NUM> is a wideband-CC UE that can use a NW channel band as <NUM> CC. UE #<NUM> is an intra-band CA UE that can run CA using <NUM> bands obtained by dividing an NW channel band. UE #<NUM> is a non-CA narrowband UE that uses only one of the <NUM> bands and does not run CA.

A wideband-CC UE may be referred to as a "wideband UE," which has been mentioned earlier, and an intra-band CA UE and a non-CA narrowband UE may be each referred to as a "narrowband UE," which has also been mentioned earlier. A NW channel band may be referred to as a "wideband CC. " The <NUM> bands may be each referred to as a "narrowband CC.

The intra-band CA UE may perform baseband signal processing on the assumption that <NUM> RF chains constitute <NUM> wideband CC, or perform baseband signal processing for each of the <NUM> RF chains. Also, the intra-band CA UE may use <NUM> or more narrowband CCs. For example, the intra-band CA UE may process a <NUM>-MHz channel band by using <NUM> RF chains that can each process a <NUM>-MHz band.

In this drawing, a guard band is provided between <NUM> CCs used by the intra-band CA UE, but the guard band does not have to be provided.

When UEs having different UE capabilities co-exist like this, the following problems might arise:.

So, the present inventors have come up with the idea of allowing a wideband-CC UE to receive multiple SS blocks that are transmitted in each of a number of frequency bands in a NW channel band. By this means, even when a wideband-CC UE and an intra-band CA UE co-exist, it is possible to use a wideband efficiently depending on what capabilities user terminals have.

Now, embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Note that the radio communication methods according to the herein-contained embodiments may be used individually or may be used in combination.

According to a first embodiment of the present invention, a number of SS blocks are transmitted (multi-SS block operation) at different frequency locations (frequency resources) within a NW channel band.

A wideband-CC UE may receive a number of SS blocks, transmitted respectively in a plurality of narrowband CCs in a wideband CC, and perform transmission and/or receipt using the wideband CC, based on at least one of the plurality of SS blocks.

For example, by performing measurements using a number of SS blocks, the accuracy of measurements can be improved when a number of narrowband CCs all have varying channel characteristics.

Now, a number of examples of multi-SS block operations to use multiple SS blocks in a wideband CC will be described below.

Here, a UE to use multiple narrowband CCs detects multiple SS blocks. This enables the UE to perform initial access procedures at multiple frequency locations.

<FIG> is a diagram to show an example of first multi-SS block operation. In this drawing, the NW channel band is <NUM>. A wideband-CC UE can use a channel band as <NUM> wideband CC. An intra-band CA UE and a non-CA narrowband UE use a narrowband CC having a bandwidth half the channel bandwidth. In this drawing, the bandwidth of a narrowband CC is <NUM>. The intra-band CA UE runs CA using <NUM> narrowband CCs in the NW channel band. The non-CA narrowband UE uses one of the <NUM> narrowband CCs in the NW channel band. There may be <NUM> or more narrowband CCs in the NW channel band.

The NW transmits SS blocks in each of the multiple narrowband CCs. The number of synchronization signals in the wideband CC and their frequency locations are selected by the NW. Here, assume that <NUM> narrowband CCs are used by the same base station. The UEs may run inter-base station CA (DC) using contiguous CCs belonging to multiple different base stations.

The wideband-CC UE and the intra-band CA UE detect a number of SS blocks. The non-CA narrowband UE detects <NUM> SS block. After detecting SS blocks, the UEs perform initial access procedures.

In initial access procedures, the UEs may use any of the narrowband CCs.

The wideband-CC UE may perform RRM measurements with respect to multiple narrowband CCs (multiple SS blocks) during initial access procedures. By this means, even when every narrowband CC shows varying channel characteristics, accurate channel estimation can be performed over a wideband from an early stage. Also, the intra-band CA UE performing RRM measurements with respect to multiple narrowband CCs (multiple SS blocks) during initial access procedures, so that the intra-band CA UE can run CA immediately after entering RRC-connected mode.

The UEs may perform RRM measurements using an anchor SS block specified by the NW among multiple SS blocks. Also, different types of RRM measurements may be applied to the anchor SS block and non-anchor SS blocks.

In addition, when the NW designates an anchor SS block to the UE, part of the processes including transmission of system information (for example, RMSI (Remaining Minimum System Information)), monitoring of the common search space, RACH procedures, paging and radio link monitoring (RLM) may be performed using the CC including the anchor SS block, and some of the rest of the processes may be performed using CCs including non-anchor SS blocks. That is, the anchor SS block and non-anchor SS blocks may have different roles. The RMSI is the minimum system information that is necessary for communication, such as SIBs (System Information Blocks).

The system information may indicate the presence of other SS blocks, or represent parameters related to these SS blocks. After having read <NUM> SS block, the wideband-CC UE and/or the intra-band CA UE may read system information based on the contents of this SS block. Also, each UE may perform rate matching and/or puncturing based on detected SS blocks and/or SS blocks indicated in the system information.

Here, a UE to use multiple narrowband CCs detects at least one of multiple SS blocks, and has additional SS blocks configured.

<FIG> is a diagram to show an example of second multi-SS block operation. An anchor SS block is transmitted within a specific narrowband CC in the NW channel band, and non-anchor SS blocks are transmitted in other narrowbands in the NW channel band.

The wideband-CC UE, the intra-band CA UE, and the non-CA narrowband UE all monitor <NUM> anchor SS block. After an anchor SS block is detected, non-anchor SS blocks are configured for the wideband-CC UE and the intra-band CA UE based on system information.

Parameters that are different from those of the anchor SS block may be configured for non-anchor SS blocks. The parameter may be, for example, the cycle of SS blocks, the contents of SS block, and so on. The cycle of anchor SS blocks does not have to be the cycle of transmitting anchor SS blocks, and may be, for example, the cycle of monitoring anchor SS blocks. In this drawing, the cycle of transmitting anchor SS blocks and non-anchor SS blocks, and the cycle of monitoring anchor SS blocks is configured to be <NUM>, and the cycle of monitoring non-anchor SS blocks is configured to be <NUM>.

Non-anchor SS blocks may be used during initial access procedures. In this case, non-anchor SS blocks may be configured by means of system information. Also, even during initial access procedures, RRM measurements for multiple different CCs are made possible. For example, a UE reads an SS block and reads the system information, and non-anchor SS blocks, RRM measurement parameters, including an indication of RRM measurements are conducted or not, and RACH resources are configured. Following this, the UE performs initial access procedures and RRM measurements. Message <NUM> may be used to send a report of measurement results, and the report may include measurement results of multiple narrowband CCs.

According to the second configuration described above, it is possible to configure additional SS blocks in a flexible manner.

According to the first embodiment described above, SS blocks are transmitted in each narrowband CC in a wideband CC, so that it is possible to off-load the traffic over multiple narrowband CCs even during initial access procedures and prevent the concentration of traffic in specific narrowband CCs.

Also, even when wideband UEs and narrowband UEs co-exist, a wideband can be used efficiently.

According to a second embodiment of the present invention, <NUM> SS block is transmitted (single-SS block operation) at <NUM> frequency location in a NW channel band.

Following SS block-based random access procedures, an intra-band CA UE may perform transmission and/or receipt in multiple narrowband CCs, based on multiple specific signals (for example, synchronization/tracking signals or SS blocks) that are transmitted respectively in multiple narrowband CCs in the band of a wideband CC.

In most cases, using <NUM> SS block is sufficient for the intra-band CA UE. Also, using <NUM> SS block is effective when there are no significant differences in channel characteristics among multiple narrowband CCs. Since the UE only needs to detect <NUM> SS block, the load of detection can be reduced.

Now, a number of examples of single-SS block operations to use <NUM> SS block in a wideband CC will be described below.

Here, the frequency locations and synchronization/tracking signals are configured after the intra-band CA UE detects an SS block (during or after initial access procedures).

<FIG> is a diagram to show an example of first single-SS block operation. <NUM> common SS block is transmitted in a wideband CC and narrowband CCs that overlap each other. Each UE may detect <NUM> SS block as in existing methods. To prevent concentration of traffic in narrowband CCs, after the intra-band CA UE detects the SS block, a number of narrowband CCs are allocated to that UE, and the intra-band CA UE runs CA by using multiple narrowband CCs. This makes it possible to off-load the traffic over multiple narrowband CCs.

After a non-CA narrowband UE detects the SS block in a given narrowband CC, narrowband CCs of different frequencies may be allocated to the UE.

When UEs use narrowband CCs of varying frequencies, the problems have to do with synchronization. Then, synchronization and/or tracking signals for synchronization and/or tracking are configured in each narrowband CC that is allocated to the intra-band CA UE or the non-CA narrowband UE. For example, the synchronization/tracking signal may be one of the PSS, the SSS, the CSI (Channel State Information)-RS for L1/L3, the DM (Demodulation)-RS, the PT (Phase Noise)-RS, and the tracking RS. The PT-RS is used to correct phase noise. The tracking RS is used to maintain synchronization, and may be one of the DM-RS, the CSI-RS and the PT-RS, or may be yet another RS.

The synchronization/tracking signals used by the intra-band CA UE may be shared with the wideband-CC UE.

The transmission of the synchronization/tracking signals may be configured to be periodic, aperiodic or semi-persistent. Aperiodic synchronization/tracking signal transmission may be configured by DCI (Downlink Control Information). When synchronization/tracking signals are transmitted aperiodically, <NUM> DCI may trigger synchronization/tracking signals for multiple narrowband CCs (cross-carrier scheduling). Semi-persistent synchronization/tracking signal transmission may be configured by the MAC CE (Medium Access Control Control Element) and/or DCI. When synchronization/tracking signals are transmitted semi-persistently, synchronization/tracking signals are transmitted periodically during the period from activation by the NW to deactivation.

Synchronization/tracking signals are used for RRM measurements. The SS block is used for RRM measurements even when synchronization/tracking signals are configured. If the frequency location of the SS block is at the boundary of <NUM> neighbor narrowband CCs allocated to the intra-band CA UE, and the intra-band CA UE measures that SS block, an MG (Measurement Gap) is required for retuning. Alternatively, an MG may be configured if a narrowband CC allocated to the intra-band CA UE includes no SS block or includes only a part of the SS block.

The frequency location of the SS block does not have to be at the center of a wideband CC, and does not have to be at the center of a narrowband CC. For measurements between cells (between sites), the frequency location of the SS block is preferably aligned with the frequency location of the SS block in other cells. If RRM measurements using synchronization/tracking signals are not possible, an RS for measurement may be transmitted at a frequency location apart from the synchronization/tracking signals. Also, an MG may be configured at the timing of the SS block, and the intra-band CA UE may detect the SS block in the MG.

Here, instead of synchronization/tracking signals, an SS block is configured.

<FIG> is a diagram to show an example of second single-SS block operation. Similar to the first single-SS block operation, each UE detects <NUM> SS block. Similar to the first single-SS block operation, after the intra-band CA UE detects the SS block, a number of narrowband CCs are allocated to that UE, and the intra-band CA UE runs CA by using multiple narrowband CCs.

An SS block is configured in each narrowband CC that is allocated to the intra-band CA UE or the non-CA narrowband UE. The transmission of the SS block may be configured to be periodic, aperiodic or semi-persistent.

This allows each UE to read the PBCH in the SS block.

Here, an SS block is transmitted in a specific narrowband CC that overlaps a wideband CC.

<FIG> is a diagram to show an example of third single-SS block operation. The frequency location of the SS block is always aligned between the intra-band CA UE and the wideband-CC UE. In this drawing, the SS block is transmitted at the center frequency in <NUM> narrowband CC of <NUM> narrowband CCs.

After the intra-band CA UE detects an SS block in a given narrowband CC, another narrowband CC is configured, and synchronization/tracking signals or an SS block is configured in the configured narrowband CC. The transmission of the synchronization/tracking signals or the SS block may be configured to be periodic, aperiodic or semi-persistent.

In the first single-SS block operation and the second single-SS block operation, the intra-band CA UE needs retuning and MGs when measuring SS blocks outside the narrowband CC. According to the third single-SS block operation, retuning and MGs are not necessary because the frequency location of the SS block does not change before and after initial access procedures. Consequently, the procedures of the third single-SS block operation are simplified compared to the first single-SS block operation and the second single-SS block operation.

When a wideband CC overlaps with an odd number of narrowband CCs and the intra-band CA UE runs CA using an odd number of narrowband CCs, the SS block is transmitted at the center frequency of the center narrowband CC, so that the frequency location of the SS block can be aligned with the center frequency of the wideband CC. By measuring the SS block at the center frequency of a wideband CC, it is possible to improve the accuracy of measurements of channel characteristics.

When a wideband CC overlaps with an even number of narrowband CCs and the intra-band CA UE runs CA using an even number of narrowband CCs, the frequency location of the SS block is not at the center frequency of the wideband CC, and is likely to be inclined to either side.

Now, with a third embodiment of the present invention, the method of generating an RS for use for wideband-CC UEs and intra-band CA UEs will be described below. The present embodiment may be combined with the first embodiment and/or the second embodiment.

The reference signal here may be any of the DM-RS, the tracking RS, the CSI-RS, the PT-RS and the SRS. The following <NUM> approaches may be possible to generate the reference signal. Here, the RS may be an RS for DL or an RS for UL.

<FIG> is a diagram to show approach <NUM> to generate RSs.

Approach <NUM>: Common RS #<NUM> is used for a wideband-CC UE and an intra-band CA UE. In this case, the UEs need to know the NW channel bandwidth (the bandwidth of a wideband CC).

Because the RS sequence that is generated extends over a wideband CC, when a guard band is provided, the part of the RS sequence on the guard band is punctured. If no guard band is provided, the RS extends over multiple CCs.

Approach <NUM>: RS #<NUM> and RS #<NUM> are generated on a per block basis. The NW channel band is comprised of multiple blocks. The size of a block may be the minimum channel bandwidth, the UE channel bandwidth (for example, the bandwidth of a narrowband CC), and so forth. The size of a block in this drawing matches the bandwidth of a narrowband CC. The RS for a wideband-CC UE is generated by connecting a number of blocks of RSs. If a guard band is provided, the RS sequence is generated taking the guard band into account.

When the number of narrowband CCs included in a wideband CC increases, RSs for an increased number of narrowband CCs can be generated. Also, MU-MIMO for the wideband-CC UE and the intra-band CA UE becomes simple. Also, the UE to use narrowband CCs does not need to know the NW channel bandwidth.

In both approach <NUM> and approach <NUM>, when guard bands are provided, the RS sequence is punctured.

According to approach <NUM> or approach <NUM>, the wideband-CC UE and the intra-band CA UE use the same RS, so that cell operation and planning become simple.

Also, the wideband-CC UE may use the RS of approach <NUM>, and the intra-band CA UE may use the RS of approach <NUM>.

With a fourth embodiment of the present invention, initial access procedures will be described. The present embodiment may be combined with the first embodiment and/or the second embodiment.

It is preferable, in order to reduce the overhead of reporting system information, to use a common RMSI for an intra-band CA UE and a wideband-CC UE.

The NW has no way of knowing whether a UE before initial access procedures has the capability to use a band that is wider than the minimum channel band, and therefore the RMSI is preferably transmitted in the SS block band or in the smallest channel band that all UEs can support. This allows all of a wideband-CC UE, an intra-band CA UE and a non-CA narrowband UE to read the RMSI. For example, assuming a carrier frequency lower than <NUM>, the minimum channel bandwidth is <NUM>. Also, for example, at a carrier frequency higher than <NUM>, the minimum channel bandwidth is <NUM>. For example, the SS block bandwidth is <NUM>.

A wideband can be used for configurations related to the RACH (Random Access CHannel). However, a wideband is not used until the NW learns what bandwidth-related capabilities a UE has. Therefore, it is necessary to configure the RACH using bands equal to or less than the minimum channel bandwidth.

<FIG> is a diagram to show an example of initial random access procedures. A UE detects an SS block of an SS block bandwidth. The SS block contains the configuration of the RMSI. The UE receives an RMSI of the minimum channel bandwidth based on the contents of the SS block. The UE transmits a RACH (also referred to as a "PRACH (Physical Random Access CHannel)," "random access preamble," "message <NUM>," etc.), thereby performing initial access procedures. A wideband (for example, the NW channel band) can be used during initial access procedures or after initial access procedures. The NW channel bandwidth may be referred to as the "maximum channel bandwidth.

The information for which a wideband may be used can be any of the RACH, messages <NUM>, <NUM> and <NUM>, and on-demand SIBs. An on-demand SIB is a SIB that is transmitted upon request from the UE.

Several options such as listed below may be possible for using a wideband:.

According to Options <NUM> to <NUM>, a wideband-CC UE and an intra-band CA UE can use a band wider than the minimum channel band during initial access procedures.

If such initial access procedures are possible, the bandwidth to be used can be changed flexibly depending on UE capabilities during initial access procedures, so that a wideband can be used efficiently.

To change the band to be used, it may be necessary to report the frequency location of the information to be transmitted and received. For example, a UE first detects the frequency location of the SS block, but has no information regarding the frequency location of the information to be transmitted and received following that. Therefore, frequency location information to show the frequency location (for example, the PRB, other frequency units, etc.) and the bandwidth (for example, the number of PRBs, the number of other frequency units, etc.) of specific information such as one of system information, the RACH, message <NUM> and message <NUM> may be reported. The frequency location information may be reported from the NW to the UE, or may be reported from the UE to the NW.

For the frequency location information, the following concerns need to be taken into consideration:.

For example, when UEs having different UE capabilities co-exist, the center frequency of a narrowband CC does not necessarily match the center frequency of a wideband CC.

If a frequency band that is allocated to specific information (specific information band) includes the SS block band, the frequency location information may show, among the PRBs included in the specific information band, the number of PRBs located at lower frequencies than the frequency location of the SS block and the number of PRBs located at higher frequencies than the frequency location of the SS block. By this means, the frequency location information can show the band of specific information (the frequency location and the bandwidth) based on the frequency location of the SS block.

The NW channel band may be split into multiple blocks. The frequency location information may show the band of specific information in units of blocks having a given bandwidth. The size of a block may be any of the SS block bandwidth, the minimum channel bandwidth and the bandwidth of an RBG (Resource Block Group).

The frequency location information may use the number of blocks instead of the number of PRBs described above.

Furthermore, the frequency location information may indicate the relative frequency location of specific information with respect to the SS block. The frequency location may represent the resource unit corresponding to the center frequency of the specific information's band, or represent the resource unit corresponding to the lowest frequency and/or the highest frequency of the specific information band. The frequency location information may include information to show the bandwidth of specific information's band (for example, the number of unit resources). The unit resource is, for example, a block and/or a PRB.

The frequency location information may further show the frequency location of specific information using the PRB index in each block.

<FIG> is a diagram to show an example of frequency location information. The frequency location information in this drawing indicates the frequency location of the RMSI. This frequency location information indicates that the frequency location of the RMSI is in the seventh PRB in the second block in the lower frequency direction (the left direction in the drawing) from the block where the SS block is located.

The frequency location information may define the frequency location of specific information based on the frequency location of <NUM> SS block detected by the UE among the multiple SS blocks in the first embodiment. Also, the frequency location information may indicate which SS block's frequency location is used as a reference among the multiple SS blocks in the first embodiment.

Note that the frequency location information may indicate the frequency location of specific information to be transmitted or received following that, based on the frequency location of specific information such as one of system information, the RACH, and messages <NUM> to <NUM>, instead of an SS block. The frequency location information may be included in one of an SS block, system information, the RACH, and messages <NUM> to <NUM>.

By using such frequency location information, it is possible to show the frequency location of subsequent information based on the frequency location of information that is received earlier. By this means, even when UEs having different UE capabilities co-exist, it is possible to properly report the band to be used.

Now, the structure of a radio communication system according to one embodiment of the present invention will be described below. In this radio communication system, communication is performed using one of the radio communication methods according to the herein-contained embodiments of the present invention, or a combination of these.

<FIG> is a diagram to show an exemplary schematic structure of a radio communication system according to one embodiment of the present invention. A radio communication system <NUM> can adopt carrier aggregation (CA) and/or dual connectivity (DC) to group a plurality of fundamental frequency blocks (component carriers) into one, where the LTE system bandwidth (for example, <NUM>) constitutes <NUM> unit.

Note that the radio communication system <NUM> may be referred to as "LTE (Long Term Evolution)," "LTE-A (LTE-Advanced)," "LTE-B (LTE-Beyond)," "SUPER <NUM>," "IMT-Advanced," "<NUM> (4th generation mobile communication system)," "<NUM> (5th generation mobile communication system)," "NR (New Radio)," "FRA (Future Radio Access)," "New-RAT (Radio Access Technology)," and so on, or may be seen as a system to implement these.

The radio communication system <NUM> includes a radio base station <NUM> that forms a macro cell C1, with a relatively wide coverage, and radio base stations 12a to 12c that are placed within the macro cell C1 and that form small cells C2, which are narrower than the macro cell C1. Also, user terminals <NUM> are placed in the macro cell C1 and in each small cell C2. The arrangement, number and so on of cells and user terminals are not limited to those illustrated in the drawings.

The user terminals <NUM> can connect with both the radio base station <NUM> and the radio base stations <NUM>. The user terminals <NUM> may use the macro cell C1 and the small cells C2 at the same time by means of CA or DC. Furthermore, the user terminals <NUM> may apply CA or DC using a plurality of cells (CCs) (for example, <NUM> or fewer CCs or <NUM> or more CCs).

A structure may be employed here in which wire connection (for example, means in compliance with the CPRI (Common Public Radio Interface) such as optical fiber, the X2 interface and so on) or wireless connection is established between the radio base station <NUM> and the radio base station <NUM> (or between <NUM> radio base stations <NUM>).

OFDMA is a multi-carrier communication scheme to perform communication by dividing a frequency bandwidth into a plurality of narrow frequency bandwidths (subcarriers) and mapping data to each subcarrier. SC-FDMA is a single-carrier communication scheme to mitigate interference between terminals by dividing the system bandwidth into bands formed with one or continuous resource blocks per terminal, and allowing a number of terminals to use mutually different bands. Note that, uplink and downlink radio access schemes are not limited to these combinations, and other radio access schemes may be used.

In the radio communication system <NUM>, a downlink shared channel (PDSCH (Physical Downlink Shared CHannel)), which is used by each user terminal <NUM> on a shared basis, a broadcast channel (PBCH (Physical Broadcast CHannel)), downlink L1/L2 control channels and so on are used as downlink channels. User data, higher layer control information and SIBs (System Information Blocks) are communicated in the PDSCH. Also, the MIB (Master Information Block) is communicated in the PBCH.

The downlink L1/L2 control channels include a PDCCH (Physical Downlink Control CHannel), an EPDCCH (Enhanced Physical Downlink Control CHannel), a PCFICH (Physical Control Format Indicator CHannel), a PHICH (Physical Hybrid-ARQ Indicator CHannel) and so on. Downlink control information (DCI), including PDSCH and/or PUSCH scheduling information, is communicated by the PDCCH.

Note that scheduling information may be reported in DCI. For example, DCI to schedule receipt of DL data may be referred to as a "DL assignment," and DCI to schedule UL data transmission may also be referred to as a "UL grant.

The number of OFDM symbols to use for the PDCCH is communicated by the PCFICH. HARQ (Hybrid Automatic Repeat reQuest) delivery acknowledgment information (also referred to as, for example, "retransmission control information," "HARQ-ACKs," "ACK/NACKs," etc.) in response to the PUSCH is transmitted by the PHICH. The EPDCCH is frequency-division-multiplexed with the PDSCH (downlink shared data channel) and used to communicate DCI and so on, like the PDCCH.

In the radio communication system <NUM>, an uplink shared channel (PUSCH (Physical Uplink Shared CHannel)), which is used by each user terminal <NUM> on a shared basis, an uplink control channel (PUCCH (Physical Uplink Control CHannel)), a random access channel (PRACH (Physical Random Access CHannel)) and so on are used as uplink channels. User data, higher layer control information and so on are communicated by the PUSCH. Also, in the PUCCH, downlink radio quality information (CQI (Channel Quality Indicator)), delivery acknowledgment information, scheduling requests (SRs) and so on are communicated. By means of the PRACH, random access preambles for establishing connections with cells are communicated.

In the radio communication system <NUM>, cell-specific reference signals (CRSs), channel state information reference signals (CSI-RSs), demodulation reference signals (DMRSs), positioning reference signals (PRSs) and so on are communicated as downlink reference signals. Also, in the radio communication system <NUM>, measurement reference signals (SRSs (Sounding Reference Signals)), demodulation reference signals (DMRSs) and so on are communicated as uplink reference signals. Note that the DMRSs may be referred to as "user terminal-specific reference signals (UE-specific reference signals). " Also, the reference signals to be communicated are by no means limited to these.

<FIG> is a diagram to show an exemplary overall structure of a radio base station according to one embodiment of the present invention. A radio base station <NUM> has a plurality of transmitting/receiving antennas <NUM>, amplifying sections <NUM>, transmitting/receiving sections <NUM>, a baseband signal processing section <NUM>, a call processing section <NUM> and a communication path interface <NUM>. Note that one or more transmitting/receiving antennas <NUM>, amplifying sections <NUM> and transmitting/receiving sections <NUM> may be provided.

In the baseband signal processing section <NUM>, the user data is subjected to transmission processes, including a PDCP (Packet Data Convergence Protocol) layer process, user data division and coupling, RLC (Radio Link Control) layer transmission processes such as RLC retransmission control, MAC (Medium Access Control) retransmission control (for example, an HARQ (Hybrid Automatic Repeat reQuest) transmission process), scheduling, transport format selection, channel coding, an inverse fast Fourier transform (IFFT) process and a precoding process, and the result is forwarded to each transmitting/receiving section <NUM>. Furthermore, downlink control signals are also subjected to transmission processes such as channel coding and an inverse fast Fourier transform, and forwarded to each transmitting/receiving section <NUM>.

Baseband signals that are pre-coded and output from the baseband signal processing section <NUM> on a per antenna basis are converted into a radio frequency band in the transmitting/receiving sections <NUM>, and then transmitted. The radio frequency signals having been subjected to frequency conversion in the transmitting/receiving sections <NUM> are amplified in the amplifying sections <NUM>, and transmitted from the transmitting/receiving antennas <NUM>. The transmitting/receiving sections <NUM> can be constituted by transmitters/receivers, transmitting/receiving circuits or transmitting/receiving apparatus that can be described based on general understanding of the technical field to which the present invention pertains. Note that a transmitting/receiving section <NUM> may be structured as a transmitting/receiving section in one entity, or may be constituted by a transmitting section and a receiving section.

In the baseband signal processing section <NUM>, user data that is included in the uplink signals that are input is subjected to a fast Fourier transform (FFT) process, an inverse discrete Fourier transform (IDFT) process, error correction decoding, a MAC retransmission control receiving process, and RLC layer and PDCP layer receiving processes, and forwarded to the higher station apparatus <NUM> via the communication path interface <NUM>. The call processing section <NUM> performs call processing (such as setting up and releasing communication channels), manages the state of the radio base stations <NUM> and manages the radio resources.

The communication path interface section <NUM> transmits and receives signals to and from the higher station apparatus <NUM> via a given interface. Also, the communication path interface <NUM> may transmit and receive signals (backhaul signaling) with other radio base stations <NUM> via an inter-base station interface (which is, for example, optical fiber that is in compliance with the CPRI (Common Public Radio Interface), the X2 interface, etc.).

Also, the transmitting/receiving sections <NUM> may respectively transmit, a number of synchronization signal blocks (for example, SS blocks) in a number of frequency bands (for example, multiple narrowband CCs) in a specific frequency band (for example, a wideband CC, a NW channel band, etc.). Also, after <NUM> synchronization signal block (for example, an anchor SS block) among the synchronization signal blocks is received at the user terminal <NUM>, the transmitting/receiving sections <NUM> may transmit a parameter to indicate other synchronization signal blocks (for example, non-anchor SS blocks) among the synchronization signal blocks.

Furthermore, the transmitting/receiving sections <NUM> may transmit a synchronization signal block (for example, an SS block) in part of frequency band (for example, a narrowband) in a specific frequency band (for example, a wideband CC, a NW channel band, etc.). Also, after random access procedures based on the synchronization signal block, the transmitting/receiving sections <NUM> may transmit a number of specific signals (for example, synchronization/tracking signals, SS blocks, etc.) in a number of frequency bands in a specific frequency band, respectively.

<FIG> is a diagram to show an exemplary functional structure of a radio base station according to one embodiment of the present invention. Note that, although this example primarily shows functional blocks that pertain to characteristic parts of the present embodiment, the radio base station <NUM> has other functional blocks that are necessary for radio communication as well.

The baseband signal processing section <NUM> at least has a control section (scheduler) <NUM>, a transmission signal generation section <NUM>, a mapping section <NUM>, a received signal processing section <NUM> and a measurement section <NUM>. Note that these configurations have only to be included in the radio base station <NUM>, and some or all of these configurations may not be included in the baseband signal processing section <NUM>.

The control section <NUM>, for example, controls the generation of signals in the transmission signal generation section <NUM>, the allocation of signals by the mapping section <NUM>, and so on. Furthermore, the control section <NUM> controls the signal receiving processes in the received signal processing section <NUM>, the measurements of signals in the measurement section <NUM>, and so on.

The control section <NUM> controls the scheduling (for example, resource allocation) of system information, downlink data signals (for example, signals transmitted in the PDSCH) and downlink control signals (for example, signals communicated in the PDSCH and/or the EPDCCH). Also, the control section <NUM> controls the generation of downlink control signals, downlink data signals and so on, based on the results of deciding whether or not retransmission control is necessary for uplink data signals, and so on. Also, the control section <NUM> controls the scheduling of synchronization signals (for example, the PSS (Primary Synchronization Signal)/SSS (Secondary Synchronization Signal)), downlink reference signals (for example, the CRS, the CSI-RS, the DMRS, etc.) and so on.

The control section <NUM> controls scheduling such as uplink data signal (for example, signal transmitted on PUSCH), uplink control signals (for example, signals transmitted on PUCCH and/or PUSCH, including delivery acknowledgment information of delivery dependency, etc.), random access preamble (for example, a signal transmitted on PRACH) and uplink reference signal.

The transmission signal generation section <NUM> generates downlink signals (downlink control signals, downlink data signals, downlink reference signals and so on) based on commands from the control section <NUM>, and outputs these signals to the mapping section <NUM>. The transmission signal generation section <NUM> can be constituted by a signal generator, a signal generating circuit or signal generating apparatus that can be described based on general understanding of the technical field to which the present invention pertains.

For example, the transmission signal generation section <NUM> generates DL assignments, which report downlink data allocation information, and/or UL grants, which report uplink data allocation information, based on commands from the control section <NUM>. DL assignments and UL grants are both DCI, in compliance with DCI format. Also, the downlink data signals are subjected to the coding process, the modulation process and so on, by using coding rates and modulation schemes that are determined based on, for example, channel state information (CSI) from each user terminal <NUM>.

The mapping section <NUM> maps the downlink signals generated in the transmission signal generation section <NUM> to given radio resources based on commands from the control section <NUM>, and outputs these to the transmitting/receiving sections <NUM>. The mapping section <NUM> can be constituted by a mapper, a mapping circuit or mapping apparatus that can be described based on general understanding of the technical field to which the present invention pertains.

The received signal processing section <NUM> performs receiving processes (for example, demapping, demodulation, decoding and so on) of received signals that are input from the transmitting/receiving sections <NUM>. Here, the received signals include, for example, uplink signals transmitted from the user terminal <NUM> (uplink control signals, uplink data signals, uplink reference signals, etc.). For the received signal processing section <NUM>, a signal processor, a signal processing circuit or signal processing apparatus that can be described based on general understanding of the technical field to which the present invention pertains can be used.

The received signal processing section <NUM> outputs the decoded information acquired through the receiving processes to the control section <NUM>. For example, when a PUCCH to contain an HARQ-ACK is received, the received signal processing section <NUM> outputs this HARQ-ACK to the control section <NUM>. Also, the received signal processing section <NUM> outputs the received signals and/or the signals after the receiving processes to the measurement section <NUM>.

For example, the measurement section <NUM> may perform RRM (Radio Resource Management) measurements, CSI (Channel State Information) measurements and so on, based on the received signals. The measurement section <NUM> may measure the received power (for example, RSRP (Reference Signal Received Power)), the received quality (for example, RSRQ (Reference Signal Received Quality), SINR (Signal to Interference plus Noise Ratio), etc.), the signal strength (for example, RSSI (Received Signal Strength Indicator)), transmission path information (for example, CSI), and so on. The measurement results may be output to the control section <NUM>.

Also, the control section <NUM> may control transmission and/or receipt using a specific frequency band during random access procedures. Furthermore, the control section <NUM> may control the transmission and/or receipt of frequency location information, which indicates the frequency location of specific information with respect to at least one of the frequency locations of multiple synchronization signal blocks.

Furthermore, the control section <NUM> may control the transmission and/or receipt of a reference signal in multiple frequency bands. Also, the control section <NUM> may control the transmission/receipt of frequency location information, which indicates the location of specific information with respect to the location of a synchronization signal block.

<FIG> is a diagram to show an exemplary overall structure of a user terminal according to one embodiment of the present invention. A user terminal <NUM> has a plurality of transmitting/receiving antennas <NUM>, amplifying sections <NUM>, transmitting/receiving sections <NUM>, a baseband signal processing section <NUM> and an application section <NUM>. Note that one or more transmitting/receiving antennas <NUM>, amplifying sections <NUM> and transmitting/receiving sections <NUM> may be provided.

Radio frequency signals that are received in the transmitting/receiving antennas <NUM> are amplified in the amplifying sections <NUM>. The transmitting/receiving sections <NUM> receive the downlink signals amplified in the amplifying sections <NUM>. The received signals are subjected to frequency conversion and converted into the baseband signal in the transmitting/receiving sections <NUM>, and output to the baseband signal processing section <NUM>. A transmitting/receiving section <NUM> can be constituted by a transmitters/receiver, a transmitting/receiving circuit or transmitting/receiving apparatus that can be described based on general understanding of the technical field to which the present invention pertains. Note that a transmitting/receiving section <NUM> may be structured as a transmitting/receiving section in one entity, or may be constituted by a transmitting section and a receiving section.

The baseband signal processing section <NUM> performs, for the baseband signal that is input, an FFT process, error correction decoding, a retransmission control receiving process and so on. Downlink user data is forwarded to the application section <NUM>. The application section <NUM> performs processes related to higher layers above the physical layer and the MAC layer, and so on. Also, in the downlink data, the broadcast information can be also forwarded to the application section <NUM>.

Meanwhile, uplink user data is input from the application section <NUM> to the baseband signal processing section <NUM>. The baseband signal processing section <NUM> performs a retransmission control transmission process (for example, an HARQ transmission process), channel coding, precoding, a discrete Fourier transform (DFT) process, an IFFT process and so on, and the result is forwarded to the transmitting/receiving sections <NUM>. The baseband signal that is output from the baseband signal processing section <NUM> is converted into a radio frequency band in the transmitting/receiving sections <NUM>. The radio frequency signals that are subjected to frequency conversion in the transmitting/receiving sections <NUM> are amplified in the amplifying sections <NUM>, and transmitted from the transmitting/receiving antennas <NUM>.

Also, the transmitting/receiving sections <NUM> may receive a number of synchronization signal blocks, which are transmitted, respectively, in a number of frequency bands in a specific frequency band. Also, after <NUM> synchronization signal block among the synchronization signal blocks is received, the transmitting/receiving sections <NUM> may transmit a parameter to indicate other synchronization signal blocks among the synchronization signal blocks.

Also, the transmitting/receiving sections <NUM> may receive synchronization signal blocks transmitted in some frequency bands in a specific frequency band.

<FIG> is a diagram to show an exemplary functional structure of a user terminal according to one embodiment of the present invention. Note that, although this example primarily shows functional blocks that pertain to characteristic parts of the present embodiment, the user terminal <NUM> has other functional blocks that are necessary for radio communication as well.

The control section <NUM>, for example, controls the generation of signals in the transmission signal generation section <NUM>, the allocation of signals in the mapping section <NUM>, and so on. Furthermore, the control section <NUM> controls the signal receiving processes in the received signal processing section <NUM>, the measurements of signals in the measurement section <NUM>, and so on.

Furthermore, when various kinds of information reported from the radio base station <NUM> are acquired via the received signal processing section <NUM>, the control section <NUM> may update the parameters to use in control based on these pieces of information.

The transmission signal generation section <NUM> generates uplink signals (uplink control signals, uplink data signals, uplink reference signals, etc.) based on commands from the control section <NUM>, and outputs these signals to the mapping section <NUM>. The transmission signal generation section <NUM> can be constituted by a signal generator, a signal generating circuit or signal generation apparatus that can be described based on general understanding of the technical field to which the present invention pertains.

For example, the transmission information generation section <NUM> generates uplink control signals such as delivery acknowledgement information, channel state information (CSI) and so on, based on commands from the control section <NUM>. Also, the transmission signal generation section <NUM> generates uplink data signals based on commands from the control section <NUM>. For example, when a UL grant is included in a downlink control signal that is reported from the radio base station <NUM>, the control section <NUM> commands the transmission signal generation section <NUM> to generate an uplink data signal.

The mapping section <NUM> maps the uplink signals generated in the transmission signal generation section <NUM> to radio resources based on commands from the control section <NUM>, and output the result to the transmitting/receiving sections <NUM>. The mapping section <NUM> can be constituted by a mapper, a mapping circuit or mapping apparatus that can be described based on general understanding of the technical field to which the present invention pertains.

The received signal processing section <NUM> performs receiving processes (for example, demapping, demodulation, decoding and so on) of received signals that are input from the transmitting/receiving sections <NUM>. Here, the received signals include, for example, downlink signals (downlink control signals, downlink data signals, downlink reference signals and so on) that are transmitted from the radio base station <NUM>. The received signal processing section <NUM> can be constituted by a signal processor, a signal processing circuit or signal processing apparatus that can be described based on general understanding of the technical field to which the present invention pertains. Also, the received signal processing section <NUM> can constitute the receiving section according to the present invention.

The received signal processing section <NUM> outputs the decoded information, acquired through the receiving processes, to the control section <NUM>. The received signal processing section <NUM> outputs, for example, broadcast information, system information, RRC signaling, DCI and so on, to the control section <NUM>. Also, the received signal processing section <NUM> outputs the received signals and/or the signals after the receiving processes to the measurement section <NUM>.

For example, the measurement section <NUM> may perform RRM measurements, CSI measurements, and so on, based on the received signals. The measurement section <NUM> may measure the received power (for example, RSRP), the received quality (for example, RSRQ, SINR, etc.), the signal strength (for example, RSSI), transmission path information (for example, CSI), and so on. The measurement results may be output to the control section <NUM>.

Also, the control section <NUM> may control the transmission and/or receipt using a specific frequency band based on at least one of a number of synchronization signal blocks. Also, the control section <NUM> may control transmission and/or receipt using a specific frequency band during random access procedures. Furthermore, the control section <NUM> may control the transmission and/or receipt of a reference signal in multiple frequency bands. The reference signal may be common with the reference signal for other user terminal in a specific frequency band in multiple frequency bands. Furthermore, the control section <NUM> may control the transmission and/or receipt of frequency location information, which indicates the frequency location of specific information with respect to at least one of the frequency locations of multiple synchronization signal blocks.

Also, the control section <NUM> may control transmission and/or receipt in multiple frequency bands (for example, multiple narrowband CCs) based on multiple specific signals transmitted respectively in multiple frequency bands in a specific frequency band after a random access procedure based on synchronization signal blocks. The plurality of frequency bands may be different from some frequency bands. One of the plurality of frequency bands may be the same as some frequency bands. Furthermore, the control section <NUM> may control the transmission and/or receipt of a reference signal in multiple frequency bands. The reference signal may be common with the reference signal for other user terminal (for example, a wideband CC UE) in a specific frequency band in multiple frequency bands. Also, the control section <NUM> may control the transmission/receipt of frequency location information, which indicates the location of specific information with respect to the location of a synchronization signal block.

Note that the block diagrams that have been used to describe the above embodiments show blocks in functional units. These functional blocks (components) may be implemented in arbitrary combinations of hardware and/or software. Also, the method for implementing each functional block is not particularly limited. That is, each functional block may be realized by one piece of apparatus that is physically and/or logically aggregated, or may be realized by directly and/or indirectly connecting <NUM> or more physically and/or logically separate pieces of apparatus (via wire or wireless, for example) and using these multiple pieces of apparatus.

For example, the radio base station, user terminals and so on according to one embodiment of the present invention may function as a computer that executes the processes of the radio communication method of the present invention. <FIG> is a diagram to show an exemplary hardware structure of a radio base station and a user terminal according to one embodiment of the present invention. Physically, the above-described radio base stations <NUM> and user terminals <NUM> may be formed as a computer apparatus that includes a processor <NUM>, a memory <NUM>, a storage <NUM>, communication apparatus <NUM>, input apparatus <NUM>, output apparatus <NUM> and a bus <NUM>.

For example, although only <NUM> processor <NUM> is shown, a plurality of processors may be provided. Furthermore, processes may be implemented with <NUM> processor, or processes may be implemented in sequence, or in different manners, on one or more processors.

The functions of the radio base station <NUM> and the user terminal <NUM> are implemented by allowing hardware such as the processor <NUM> and the memory <NUM> to read given software (programs), thereby allowing the processor <NUM> to do calculations, the communication apparatus <NUM> to communicate, and the memory <NUM> and the storage <NUM> to read and/or write data.

The processor <NUM> may control the whole computer by, for example, running an operating system. The processor <NUM> may be configured with a central processing unit (CPU), which includes interfaces with peripheral apparatus, control apparatus, computing apparatus, a register and so on. For example, the above-described baseband signal processing section <NUM> (<NUM>), call processing section <NUM> and so on may be implemented by the processor <NUM>.

The memory <NUM> is a computer-readable recording medium, and may be constituted by, 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/or other appropriate storage media. The memory <NUM> may be referred to as a "register," a "cache," a "main memory" (primary storage apparatus) and so on. The memory <NUM> can store executable programs (program codes), software modules and so on for implementing the radio communication methods according to embodiments of the present invention.

The communication apparatus <NUM> is hardware (transmitting/receiving apparatus) for allowing inter-computer communication by using wired and/or wireless networks, and may be referred to as, for example, a "network device," a "network controller," a "network card," a "communication module" and so on. The communication apparatus <NUM> may be configured to include a high frequency switch, a duplexer, a filter, a frequency synthesizer and so on in order to realize, for example, frequency division duplex (FDD) and/or time division duplex (TDD). For example, the above-described transmitting/receiving antennas <NUM> (<NUM>), amplifying sections <NUM> (<NUM>), transmitting/receiving sections <NUM> (<NUM>), communication path interface <NUM> and so on may be implemented by the communication apparatus <NUM>.

Note that the terminology used in this specification and the terminology that is needed to understand this specification may be replaced by other terms that communicate the same or similar meanings. For example, "channels" and/or "symbols" may be replaced by "signals" (or "signaling"). Also, "signals" may be "messages. " A reference signal may be abbreviated as an "RS," and may be referred to as a "pilot," a "pilot signal" and so on, depending on which standard applies. Furthermore, a "component carrier (CC)" may be referred to as a "cell," a "frequency carrier," a "carrier frequency" and so on.

Furthermore, a radio frame may be comprised of one or more periods (frames) in the time domain. Each of one or more periods (frames) constituting a radio frame may be referred to as a "subframe. " Furthermore, a subframe may be comprised of one or multiple slots in the time domain. A subframe may be a fixed time duration (for example, <NUM>) not dependent on the numerology.

Furthermore, a slot may be comprised of one or more symbols in the time domain (OFDM (Orthogonal Frequency Division Multiplexing) symbols, SC-FDMA (Single Carrier Frequency Division Multiple Access) symbols, and so on). Also, a slot may be a time unit based on numerology. Also, a slot may include a plurality of minislots. Each minislot may be comprised of one or more symbols in the time domain. Also, a minislot may be referred to as a "subslot.

A radio frame, a subframe, a slot, a minislot and a symbol all represent the time unit in signal communication. A radio frame, a subframe, a slot, a minislot and a symbol may be each called by other applicable names. For example, <NUM> subframe may be referred to as a "transmission time interval (TTI)," or a plurality of consecutive subframes may be referred to as a "TTI," or <NUM> slot or mini-slot may be referred to as a "TTI. " That is, a subframe and/or a TTI may be a subframe (<NUM>) in existing LTE, may be a shorter period than <NUM> (for example, <NUM> to <NUM> symbols), or may be a longer period of time than <NUM>. Note that the unit to represent the TTI may be referred to as a "slot," a "mini slot" and so on, instead of a "subframe.

For example, in LTE systems, a radio base station schedules the radio resources (such as the frequency bandwidth and transmission power that can be used in each user terminal) to allocate to each user terminal in TTI units.

The TTI may be the transmission time unit of channel-encoded data packets (transport blocks), code blocks and/or codewords, or may be the unit of processing in scheduling, link adaptation and so on. Note that, when a TTI is given, the period of time (for example, the number of symbols) in which transport blocks, code blocks and/or codewords are actually mapped may be shorter than the TTI.

Note that, when <NUM> slot or <NUM> minislot is referred to as a "TTI," one or more TTIs (that is, one or multiple slots or one or more minislots) may be the minimum time unit of scheduling. Also, the number of slots (the number of minislots) to constitute this minimum time unit of scheduling may be controlled.

A TTI having a time duration of <NUM> may be referred to as a "normal TTI" (TTI in LTE Rel. <NUM> to <NUM>), a "long TTI," a "normal subframe," a "long subframe," and so on. A TTI that is shorter than a normal TTI may be referred to as a "shortened TTI," a "short TTI," a "partial TTI" (or a "fractional TTI"), a "shortened subframe," a "short subframe," a "mini-slot," a "sub-slot" and so on.

A resource block (RB) is the unit of resource allocation in the time domain and the frequency domain, and may include one or a plurality of consecutive subcarriers in the frequency domain. Also, an RB may include one or more symbols in the time domain, and may be <NUM> slot, <NUM> minislot, <NUM> subframe or <NUM> TTI in length. <NUM> TTI and <NUM> subframe each may be comprised of one or more resource blocks. Note that one or more RBs may be referred to as a "physical resource block (PRB (Physical RB))," a "subcarrier group (SCG)," a "resource element group (REG)," a "PRB pair," an "RB pair" and so on.

For example, <NUM> RE may be a radio resource field of <NUM> subcarrier and <NUM> symbol.

Note that the structures of radio frames, subframes, slots, minislots, symbols and so on described above are merely examples. For example, configurations pertaining to the number of subframes included in a radio frame, the number of slots included per subframe or radio frame, the number of mini-slots included in a slot, the number of symbols and RBs included in a slot or a mini-slot, the number of subcarriers included in an RB, the number of symbols in a TTI, the symbol duration, the length of cyclic prefixes (CPs) and so on can be variously changed.

Also, the information and parameters described in this specification may be represented in absolute values or in relative values with respect to given values, or may be represented using other applicable information. For example, a radio resource may be specified by a given index.

The information, signals and so on that are input and/or output may be stored in a specific location (for example, in a memory), or may be managed in a control table. The information, signals and so on to be input and/or output can be overwritten, updated or appended. The information, signals and so on that are output may be deleted. The information, signals and so on that are input may be transmitted to other pieces of apparatus.

Reporting of information is by no means limited to the examples/embodiments described in this specification, and other methods may be used as well. For example, reporting of information may be implemented by using physical layer signaling (for example, downlink control information (DCI), uplink control information (UCI)), higher layer signaling and other signals and/or combinations of these.

Also, reporting of given information (for example, reporting of information to the effect that "X holds") does not necessarily have to be sent explicitly, and can be sent in an implicit way (for example, by not reporting this piece of information, by reporting another piece of information, and so on).

Decisions may be made in values represented by <NUM> bit (<NUM> or <NUM>), may be made in Boolean values that represent true or false, or may be made by comparing numerical values (for example, comparison against a given value).

As used herein, the terms "base station (BS)," "radio base station," "eNB," "gNB," "cell," "sector," "cell group," "carrier," and "component carrier" may be used interchangeably.

A base station can accommodate one or more (for example, <NUM>) cells (also referred to as "sectors"). When a base station accommodates a plurality of cells, the entire coverage area of the base station can be partitioned into multiple smaller areas, and each smaller area can provide communication services through base station subsystems (for example, indoor small base stations (RRHs (Remote Radio Heads))). The term "cell" or "sector" refers to part or all of the coverage area of a base station and/or a base station subsystem that provides communication services within this coverage.

Furthermore, the radio base stations in this specification may be interpreted as user terminals. For example, each aspect/embodiment of the present invention may be applied to a configuration in which communication between a radio base station and a user terminal is replaced with communication among a plurality of user terminals (D2D (Device-to-Device)). In this case, user terminals <NUM> may have the functions of the radio base stations <NUM> described above. In addition, terms such as "uplink" and "downlink" may be interpreted as "side. " For example, an "uplink channel" may be interpreted as a "side channel.

Certain actions which have been described in this specification to be performed by base stations may, in some cases, be performed by their upper nodes. In a network comprised of one or more network nodes with base stations, it is clear that various operations that are performed so as to communicate with terminals can be performed by base stations, one or more network nodes (for example, MMEs (Mobility Management Entities), S-GWs (Serving-Gateways) and so on may be possible, but these are not limiting) other than base stations, or combinations of these.

The aspects/embodiments illustrated in this specification may be applied to LTE (Long Term Evolution), LTE-A (LTE-Advanced), LTE-B (LTE-Beyond), SUPER <NUM>, IMT-Advanced, <NUM> (4th generation mobile communication system), <NUM> (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), CDMA <NUM>, UMB (Ultra Mobile Broadband), IEEE <NUM> (Wi-Fi (registered trademark)), IEEE <NUM> (WiMAX (registered trademark)), IEEE <NUM>, UWB (Ultra-WideBand), Bluetooth (registered trademark), systems that use other adequate radio communication systems and/or next-generation systems that are enhanced based on these.

Reference to elements with designations such as "first," "second" and so on as used herein does not generally limit the number/quantity or order of these elements. These designations are used herein only for convenience, as a method for distinguishing between <NUM> or more elements. In this way, reference to the first and second elements does not imply that only <NUM> elements may be employed, or that the first element must precede the second element in some way.

As used herein, the terms "connected" and "coupled," or any variation of these terms, mean all direct or indirect connections or coupling between <NUM> or more elements, and may include the presence of one or more intermediate elements between <NUM> elements that are "connected" or "coupled" to each other. The coupling or connection between the elements may be physical, logical or a combination of these.

As used herein, when <NUM> elements are connected, these elements may be considered "connected" or "coupled" to each other by using one or more electrical wires, cables and/or printed electrical connections, and, as a number of nonlimiting and non-inclusive examples, by using electromagnetic energy, such as electromagnetic energy having wavelengths in the radio frequency, microwave and optical (both visible and invisible) regions.

In the present specification, the phrase "A and B are different" may mean "A and B are different from each other. " The terms such as "leave" "coupled" and the like may be interpreted as well.

Claim 1:
A terminal (<NUM>) comprising:
a receiving section (<NUM>) configured to detect a first synchronization signal block including a synchronization signal and a physical broadcast channel, and receive, in a random access procedure based on the first synchronization signal block, a configuration information indicating a second synchronization signal block; and
a control section (<NUM>) configured to control reception of the second synchronization signal block based on the configuration information,
wherein when the control section (<NUM>) is configured to perform a radio resource management, RRM, measurement based on the second synchronization signal block and whole or part of the second synchronization signal block is not included in a band assigned to the terminal, the control section (<NUM>) is configured to perform the RRM measurement with a measurement gap.