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>). In addition, the specifications of LTE-A (LTE advanced and LTE Rel. <NUM>, <NUM>, <NUM> and <NUM>) have also been drafted for the purpose of achieving increased capacity and enhancement beyond LTE (LTE Rel. <NUM> and <NUM>).

Successor systems of LTE are also under study (for example, referred to as "FRA (Future Radio Access)," "<NUM> (5th Generation mobile communication system)," "<NUM>+ (plus)," "NR (New Radio)," "NX (New radio access)," "FX (Future generation radio access)," "LTE Rel. <NUM> or <NUM> and later versions," etc.).

In existing LTE systems (for example, LTE Rels. <NUM> to <NUM>), a user terminal (UE (User Equipment)) detects synchronization signals ("SS," including, for example, PSS (Primary Synchronization Signal), SSS (Secondary Synchronization Signal), etc.), following initial access procedures (also referred to as "cell search"), synchronizes with the network (for example, a base station (eNB (eNode B))), and identifies the cell to connect with (based on, for example, cell IDs (IDentifiers)).

Also, after the cell search, the user terminal receives broadcast information (MIB (Master Information Block)), which is transmitted in a broadcast channel (PBCH (Physical Broadcast CHannel)), system information (SIB (System Information Block)), which is transmitted in a downlink (DL) shared channel (PDSCH (Physical Downlink Shared CHannel)), and so on, and acquires configuration information (which may be referred to as "broadcast information," "system information," etc.) for communicating with the network.

Non-Patent Literature <NUM>: <NPL>
<NPL> discloses to introduce <NUM> measurement gap configuration IE in NR RRC Signaling. One mandatory IE for identical gap configuration. Another optional IE for independent gap configuration.

For future radio communication systems (for example, NR, <NUM>, etc.), studies are underway to define signal blocks (also referred to as "SS/PBCH blocks," "SS blocks," etc.) that contain synchronization signals (also referred to as "SS," "PSS" and/or "SSS," "NR-PSS" and/or "NR-SSS," etc.), and broadcast channels (also referred to as "broadcast signals," "PBCHs," "NR-PBCHs," etc.). A set of one or more signal blocks is also referred to as a "signal burst (SS/PBCH burst or SS burst). " In this signal burst, multiple signal blocks are transmitted in different beams at different times (also referred to as "beam sweep," etc.).

In addition, future radio communication systems are under study to conduct measurements using these signal blocks. Here, "measurements" means measuring at least one of the received power (for example, RSRP (Reference Signal Received Power)), the received quality (for example, RSRQ (Reference Signal Received Quality) or SINR (Signal to Interference plus Noise Ratio)) and the received strength (for example, RSSI (Reference Signal Strength Indicator)), and is also referred to as "RRM (Radio Resource Management) measurements" and the like.

The base station configures the timings for measurements in the UE. However, if proper measurement timings are not configured, the performance of the radio communication system may deteriorate due to, for example, the inability to measure the signal to be measured.

The present invention has been made in view of the above, and it is therefore an object of the present invention to provide a terminal, a radio communication method, a base station and a system, whereby measurement timings can be configured properly.

As defined by claim <NUM>, the invention provides a terminal comprising: a receiving section configured to receive, via higher layer signaling, first information indicating a gap offset in subframe units related to a measurement gap, MG, and second information indicating a shift time shorter than one subframe and related to the MG; and a control section configured to determine a timing of the MG based on the gap offset and the shift time.

Preferred embodiments of the terminal of claim <NUM> are defined by claims <NUM> to <NUM>.

As defined by claim <NUM>, the invention provides a radio communication method for a terminal, the method comprising: receiving, via higher layer signaling, first information indicating a gap offset in subframe units related to a measurement gap, MG, and second information indicating a shift time shorter than one subframe and related to the MG; and determining a timing of the MG based on the gap offset and the shift time.

As defined by claim <NUM>, the invention provides a base station comprising: a transmitting section configured to transmit, via higher layer signaling, first information indicating a gap offset in subframe units related to a measurement gap, MG, and second information indicating a shift time shorter than one subframe and related to the MG; and a control section configured to indicate, by the first information and the second information, a timing of the MG.

A preferred embodiment of the base station of claim <NUM> is defined by claim <NUM>.

As defined by claim <NUM>, the invention provides a system comprising a terminal and a base station, wherein: the terminal comprises: a receiving section configured to receive, via higher layer signaling, first information indicating a gap offset in subframe units related to a measurement gap, MG, and second information indicating a shift time shorter than one subframe and related to the MG; and a control section configured to determine a timing of the MG based on the gap offset and the shift time; and the base station comprises: a transmitting section configured to transmit, via higher layer signaling, the first information and the second information.

According to the present invention, measurement timings can be configured properly.

In existing LTE, UE supports inter-frequency measurements, in which measurements are conducted in non-serving carriers apart from the connecting serving carriers. In inter-frequency measurements, at least one of the reference signal received power (RSRP), the received signal strength (RSSI (Received Signal Strength Indicator)) and the reference signal received quality (for example, RSRQ) in non-serving carriers is measured.

Here, RSRP is the received power of desired signals, and is measured based on, for example, cell-specific reference signals (CRSs) and the like. Also, RSSI is the total received power of the received power of desired signals, plus the power of interference and noise. RSRQ is the ratio of RSRP to RSSI.

In a measurement gap (MG), UE switches the receiving frequency from the serving carrier to a non-serving carrier, and, by measuring at least one of RSRP, RSSI and RSRQ by using, for example, CRS, switches the receiving frequency from the non-serving carrier to the serving carrier. Here, a measurement gap is an interval for making inter-frequency measurements, and, while in this interval, the UE stops transmission and receipt in the communicating carrier and conducts measurements in another frequency carrier.

<FIG> is a diagram to show an example of an MG pattern. As shown in <FIG>, UE uses a given duration (also referred to as a "measurement gap length (MGL)"), repeated every given repetition periodicity (also referred to as "measurement gap repetition period (MGRP)"), as an MG. An MG pattern is determined by the MGL and the MGRP. When the UE receives a gap pattern indicator (gap pattern ID) through higher layer signaling (for example, RRC signaling), the UE can identify the MG pattern based on the indicator.

Also, in inter-frequency measurements, gap offsets may be reported by higher layer signaling (for example, RRC signaling). Here, as shown in <FIG>, a gap offset is the starting offset from the top of a given radio frame to the beginning of an MG, indicating the timing of the MG. Note that the UE may identify the MG pattern from a gap offset that is reported. In this case, the MG pattern is implicitly reported.

As shown in <FIG>, existing LTE systems use <NUM> patterns -- namely a gap pattern <NUM>, in which the MGL is <NUM> and the MGRP is <NUM>, and a gap pattern <NUM>, in which the MGL is <NUM> and the MGRP is <NUM>. If the MGRP is <NUM>, the gap offset [ms] is reported using an integer between <NUM> and <NUM>, and, if the MGRP is <NUM>, the gap offset [ms] is reported using an integer between <NUM> and <NUM>.

The MGL is fixed at <NUM>. The MGL is configured on the assumption that the PSS/SSS transmission periodicity is <NUM>, and that it takes <NUM> to switch the frequency from the connecting carrier to the carrier to be measured, and <NUM> to switch back the frequency.

In existing LTE systems, <NUM> pattern is configured for <NUM> UE. If the UE has only <NUM> RF chain (transmitting/receiving section), the UE conducts measurements by switching between multiple carriers. During the MG, the UE cannot communicate with the connecting carrier.

If the UE is configured to perform inter-frequency measurements for multiple carriers, the measurement periodicity for each carrier is the same. For example, each carrier's measurement periodicity is determined by (MGRP) × (the number of carriers subject to inter-frequency measurements).

<FIG> is a diagram to show examples of inter-frequency measurements. In this example, <NUM> non-serving carriers are to be measured and the MGRP is <NUM>, so that the measurement periodicity is <NUM> in each carrier. Thus, an existing MG pattern is configured for a number of carriers to be measured, in common, and <NUM> is used for inter-frequency measurement for <NUM> of a number of carriers.

For future radio communication systems (for example, NR, <NUM>, etc.), studies are underway to define signal blocks (also referred to as "SS/PBCH blocks," "SS/PBCH blocks and the like," etc.) that contain synchronization signals (also referred to as "SS," "PSS" and/or "SSS," "NR-PSS" and/or "NR-SSS," etc.), and a broadcast channel (also referred to as "broadcast signal," "PBCH," "NR-PBCH," etc.). A set of one or more signal blocks is also referred to as a "signal burst (SS/PBCH burst or SS burst). " In this signal burst, multiple signal blocks are transmitted in different beams at different times (also referred to as "beam sweep," etc.).

An SS/PBCH block is comprised of one or more symbols (for example, OFDM symbols). To be more specific, an SS/PBCH block may be comprised of a number of symbols that are consecutive. In this SS/PBCH block, PSS, SSS and NR-PBCH may be allocated within one or more different symbols. For example, research is underway to constitute an SS/PBCH block with <NUM> or <NUM> symbolsincluding a PSS of <NUM> symbol, an SSS of <NUM> symbol and a PBCH of <NUM> or <NUM> symbols.

A set of one or more SS/PBCH blocks may be referred to as an "SS/PBCH burst. " For example, an SS/PBCH burst may be formed with SS/PBCH blocks of contiguous frequency and/or time resources, or may be formed with SS/PBCH blocks of non-contiguous frequency and/or time resources. The SS/PBCH burst may be configured based on a given periodicity (may be referred to as "SS/PBCH burst periodicity") or may be configured non-periodically.

A set of one or more SS/PBCH bursts may be referred to as an "SS/PBCH burst set (SS/PBCH burst series). " SS/PBCH burst sets are configured periodically. The user terminal may control receiving processes on the assumption that SS/PBCH burst sets are transmitted periodically (following an SS/PBCH burst set periodicity).

Each SS/PBCH block in an SS/PBCH burst set is identified by a given index (SS/PBCH index). This SS/PBCH index may be any information that uniquely identifies an SS/PBCH block in an SS burst set, and may correspond to a time index.

The user terminal may assume that SS/PBCH blocks having the same SS/PBCH indices are quasi-co-located (QCL (Quai-Co-Location)), between SS/PBCH burst sets, in terms of at least one of space, average gain, delay and Doppler parameters.

Here, quasi-collocation (QCL) means that it can be assumed that at least one of the space (beams) to use to transmit multiple different SS/PBCH blocks, and the average gain, the delay and the Doppler parameters of the multiple SS/PBCH blocks is the same.

Meanwhile, the user terminal does not have to assume quasi-co-location, in terms of at least one of space, average gain, delay and Doppler parameters, among SS/PBCH blocks having different SS/PBCH indices within SS/PBCH burst sets and/or between SS/PBCH burst sets.

Studies are in progress to support capability signaling to configure MGs for different frequency measurements. The UE may use at least <NUM> frequency band (carrier frequency) of FR <NUM> (frequency lower than <NUM> (sub-<NUM>)) or FR <NUM> (frequency higher than <NUM> (above <NUM>)). Capability signaling can configure different frequency measurement MGs for FR <NUM> and FR <NUM>, separately.

For example, capability signaling reports the MG length for FR <NUM>-specific gaps and gaps per UE (the length or the duration, including, for example, {<NUM>, <NUM>, <NUM>} ms), the MG length for FR <NUM>-specific gaps (for example, {<NUM>, <NUM>, <NUM>} ms), and the MG repetition period (for example, {<NUM>, <NUM>, <NUM>} ms).

Also, studies are in progress to configure measurement timing configuration using the SS/PBCH blocks (SS/PBCH block-based measurement timing configuration (SMTC)) in the UE. The SMTC window's duration, periodicity, and timing offset and the like are reported as SMTC. In the SMTC window, SS/PBCH blocks to be measured are transmitted.

For example, candidate values for the SMTC window time length (duration or length) for both intra-frequency measurements and inter-frequency measurements are {<NUM>, <NUM>, <NUM>, <NUM>, <NUM>} ms.

For example, the SMTC window timing reference for SMTC window timing offsets is the serving cell's SFN (System Frame Number) #<NUM>. In IDLE mode, the serving cell may refer to the cell in which UE is located. For example, for intra-frequency measurements, candidate values for SMTC window timing offsets are {<NUM>, <NUM>,. , SMTC periodicity-<NUM>} ms. For example, for inter-frequency measurements, candidate values for SMTC window timing offsets are {<NUM>, <NUM>,. , SMTC periodicity-<NUM>} ms.

For example, for both intra-frequency measurements and inter-frequency measurements, candidate values for the SMTC periodicity are {<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>} ms.

FR <NUM> is under study to be used only in TDD bands, and operated synchronously between base stations. In addition, FR <NUM> is planned to be operated synchronously between carriers.

An SMTC window and MGs are configured in UE for inter-frequency measurements of FR <NUM>. As mentioned earlier, for example, the SMTC window timing offset is specified in units of <NUM>, and the SMTC window duration is specified as {<NUM>, <NUM>, <NUM>, <NUM>, <NUM>} in units of <NUM>. On the other hand, the method for specifying MG timing offsets has not been decided yet.

The times at the top and the end of the MG period are used for RF (Radio Frequency) retuning. The UE performs RF retuning to switch the carrier frequency in RF processes (transmitting/receiving processes, frequency conversion process, etc.), from the connecting frequency to the frequency to be measured, during the RF retuning time at the top of the MG, and performs RF retuning to switch from the measurement-target frequency to the connecting frequency during the RF retuning time at the end of the MG. The RF retuning time is, for example, <NUM>. The RF retuning time may be defined in the specification.

When the UE measures FR <NUM> in the MG for FR <NUM>, if the starting timing of the MG is configured to be aligned with the starting timing of the SMTC window, the UE cannot conduct measurements during the RF retuning time at the top and the end of the SMTC window.

In the example of <FIG>, FR <NUM> is the measurement target, the subcarrier spacing (SCS) of the serving cell is <NUM>, the SMTC window duration is <NUM>, the MG length is <NUM>, and the RF retuning time is <NUM>. Also, the slot duration is <NUM> when the SCS is <NUM>. Furthermore, for the SCS of <NUM>, the time locations for SSBs (SS/PBCH blocks) #<NUM> to #<NUM> are configured in the SMTC window. Also, each of the first slot and the second slot in the SMTC window includes SS/PBCH blocks.

In this example, when the starting timing of the MG is configured to be aligned with the starting timing of the SMTC window, RF retuning is in progress in the first and second slots in the SMTC window, and therefore measurements are not possible.

Moreover, in existing LTE systems, the timing offset of the MG is specified in <NUM>-ms units. In the example of <FIG>, when existing MG timing offset specifying methods are used, the starting timing of measurements in the MG cannot be aligned with the starting timing of the SMTC window.

So, the present inventors have come up with a method for specifying the timing offset for an MG, whereby the time after RF retuning in the MG can be aligned with the starting time of the measurement target (for example, SMTC window).

Now, embodiments 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.

A base station (for example, gNB, network, transmitting/receiving point, etc.) may signal MG configurations to UE via higher layer signaling. The UE conducts measurements using the MG indicated by the MG configurations. The UE conducts measurements after the RF retuning time from the top of the MG. The MG configurations may include at least one of the MG length, the MG repetition period and the MG timing offset.

The base station may signal the SMTC to the UE via higher layer signaling. The UE measures SS/PBCH blocks in the SMTC window indicated by the SMTC in the period in the MG where measurements can be performed (the period apart from the RF retuning periods in the MG). The SMTC may include at least one of the SMTC window duration, the SMTC window periodicity, and the SMTC window timing offset.

The UE may control the offset at a granularity finer than <NUM>, based on configuration information related to the MG timing offset.

Similar to <FIG>, in the example of <FIG>, FR <NUM> is the measurement target, the SCS of the serving cell is <NUM>, the SMTC window duration is <NUM>, the MG length is <NUM>, and the RF retuning time is <NUM>. Also, the slot duration is <NUM> when the SCS is <NUM>. Furthermore, for the SCS of <NUM>, the time locations for SSBs #<NUM> to #<NUM> are configured in the SMTC window. Also, the first slot and the second slot in the SMTC window each include SS/PBCH blocks.

In this example, the granularity of control for the MG starting timing is <NUM>. By using this granularity, it is possible to align the ending timing of RF retuning at the top of an MG with the starting timing of the SMTC window.

The period in the MG where measurements can be performed may be coordinated with the SMTC window duration. For example, the MG length may be the time given by adding twice the RF retuning time to the SMTC window duration. In the example of <FIG>, since the SMTC window duration is <NUM> and the RF retuning time is <NUM>, the MG length is <NUM>.

Since the granularity of control for the starting timing of the MG is finer than <NUM>, the time of the difference between the measurement starting timing in the MG (the end of RF retuning at the top of the MG) and the starting timing of the SMTC window can be shortened. By shortening this time, the MG length can be shortened. By shortening the MG length, it is possible to shorten the time DL/UL transmission is interrupted in the connecting frequency. By shortening the time to interrupt DL/UL transmission, the decline in throughput can be reduced.

The MG timing offset may be configured in the UE via higher layer signaling. This higher layer signaling may be, for example, one of RRC (Radio Resource Control) signaling, MAC (Medium Access Control) signaling, broadcast information and so on, or a combination of these.

For MAC signaling, for example, a MAC control element (MAC CE (Control Element)), a MAC PDU (Protocol Data Unit), and the like may be used. The broadcast information may be, for example, the master information block (MIB), system information blocks (SIBs), minimum system information (RMSI (Remaining Minimum System Information)), other system information (OSI) and the like.

In example <NUM>, the MG timing offset in FR <NUM> may be configured in UE at a granularity finer than <NUM>. In other words, in FR <NUM>, the unit (configuration unit, step, etc.) for specifying MG timing offsets may be smaller than <NUM>. For example, the MG timing offset may be reported to the UE via higher layer signaling (for example, RRC signaling). The MG timing offset may be aligned with the time the RF retuning time before the starting timing of the SMTC window.

The unit (step) of MG timing offsets may be <NUM> slot. Also, the SCS of the serving cell may be greater than <NUM>. For example, if the serving cell uses a <NUM>-kHz SCS, the slot duration is <NUM>.

If there are multiple serving cells, the slot duration corresponding to the largest SCS among the SCSs of multiple serving cells may be used as the unit of MG timing offsets.

The unit of MG timing offsets may be a given time smaller than <NUM>, regardless of SCS. The given time may be the RF retuning time or a time greater than the RF retuning time. Furthermore, the given time may be the slot duration of a given SCS.

According to example <NUM>, the RF tuning ending timing at the top of an MG and the SMTC window starting timing can be brought close to each other, so that the period in the SMTC window and in the MG where measurements cannot be performed can be reduced.

The unit for specifying MG timing offsets in FR <NUM> is <NUM>, and the MG timing offset to be actually configured may be the value given by adding an additional offset to an MG timing offset that is specified. The UE configures the value of the reported MG timing offset, shifted by an additional offset, as an actual MG timing offset.

The additional offset is, for example, "-RF retuning time <NUM>. " In this case, the UE sets the value given by shifting the reported MG timing offset backward by the RF retuning time, as an actual MG timing offset.

The sign of the additional offset may be negative or positive. The magnitude of the additional offset may be the RF retuning time, or the time given by adding a given value to the RF retuning time. Also, the magnitude of the additional offset may be the slot duration of a given SCS. Also, the magnitude of the additional offset may vary depending on the SCS.

The unit of MG timing offsets may be smaller than <NUM> and greater than the RF retuning time.

Whether or not to add an additional offset may be reported by signaling (for example, higher layer signaling), or may be fixed by the specification.

According to example <NUM>, even when the unit of MG timing offsets is greater than the RF retuning time, the RF tuning ending timing at the top of an MG and the SMTC window starting timing can be brought close to each other, so that the period in the SMTC window and in the MG where measurements cannot be performed can be reduced. Also, by making the unit of MG timing offsets coarser than example <NUM>, it is possible to suppress the overhead of reporting of the MG timing offset.

Also in FR <NUM>, as in example <NUM>, the unit of MG timing offsets is <NUM>, and the actual MG timing offset may be the value given by adding an additional offset to an MG timing offset that is specified.

The magnitude of the additional offset in FR <NUM> may be different than the magnitude of the additional offset in FR <NUM>. For example, the additional offset in FR <NUM> may be -<NUM>.

The magnitude of the additional offset may vary depending on frequency bands. The RF retuning time may vary depending on frequency bands. Depending on frequency bands, different SCSs may be available for use.

As in examples <NUM> to <NUM>, when the granularity of control for the starting timing of MGs is finer than <NUM>, cases might occur where an MG overlaps with only part of the subframe or the slot of the serving cell. In existing LTE systems, the starting timing and the ending timing of MGs both always coincide with subframe boundaries.

The UE may be assumed not to receive DL signals (for example, PDCCH and/or PDSCH) and/or transmit UL signals (for example, PUCCH and/or PUSCH) in slots or subframes that at least partially overlaps with MGs. Based on this assumption, even when the starting timing and/or the ending timing of an MG do not coincide with slot or subframe boundaries, the UE can transmit and receive properly.

Alternatively, when transmitting and receiving based on NR, the UE may assume that channels that fulfill specific conditions can be transmitted and received even in slots that partially overlap with MGs. A channel to fulfill specific conditions is a channel that does not overlap with an MG, and that can be processed within that channel. Channels that can be processed within these channels may be, for example, the PDCCH at the top of a slot, the PUCCH at the end of a slot (for example, a short PUCCH), and so on. Based on this assumption, even if part of NR slots overlap with MGs, the UE may be able to transmit and receive part of the channels, so that the throughput can be improved.

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

<FIG> is a diagram to show an exemplary schematic structure of a radio communication system. 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).

Between the user terminals <NUM> and the radio base station <NUM>, communication can be carried out using a carrier of a relatively low frequency bandwidth (for example, <NUM>) and a narrow bandwidth (referred to as, for example, an "existing carrier," a "legacy carrier" and so on).

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 <NUM> 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 systems <NUM>, the cell-specific reference signal (CRS (Cell-specific Reference Signal)), the channel state information reference signal (CSI-RS (Channel State Information-Reference Signal)), the demodulation reference signal (DMRS (DeModulation Reference Signal)), the positioning reference signal (PRS (Positioning Reference Signal)) and so on are communicated as downlink reference signals. Also, in the radio communication system <NUM>, the measurement reference signal (SRS (Sounding Reference Signal)), the demodulation reference signal (DMRS) and so on are communicated as uplink reference signals. Note that the DMRS may be referred to as a "user terminal-specific reference signal (UE-specific Reference Signal). " 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. 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.).

In addition, the transmitting/receiving sections <NUM> may transmit, to the user terminal <NUM>, information about the measurement gap pattern (for example, single-MG pattern or non-contiguous MG pattern) to use when measuring a plurality of synchronization signal blocks (for example, SS blocks in an SS burst set). Also, the transmitting/receiving sections <NUM> may transmit synchronization signal blocks (for example, SS blocks) based on a synchronization signal block pattern that is comprised of a plurality of synchronization signal blocks (for example, SS burst set, localized SS block, distributed SS block etc.).

The transmitting/receiving sections <NUM> of each of a plurality of cells (for example, an asynchronous network) may transmit synchronization signal blocks asynchronously with respect to each other.

Also, the transmitting/receiving sections <NUM> may transmit the synchronization signal blocks (for example, SS/PBCH blocks) during periods that are the configured (for example, in the SMTC window).

Also, the transmitting/receiving sections <NUM> may transmit information about the configurations of measurement of synchronization signal blocks (for example, SMTC). Also, the transmitting/receiving sections <NUM> may transmit information about the configurations of measurement gaps (for example, MG configurations).

<FIG> is a diagram to show an exemplary functional structure of a radio base station. 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 transmitted in the PDCCH and/or the EPDCCH, such as delivery acknowledgment information). 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 signal downlink data allocation information, and/or UL grants, which signal 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 transmitting/receiving sections <NUM> may transmit information about the configurations of measurements of synchronization signal blocks (for example, SMTC). Also, the transmitting/receiving sections <NUM> may transmit information about the configurations of measurement gaps (for example, MG configurations).

<FIG> is a diagram to show an exemplary overall structure of a user terminal. 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 synchronization signal blocks (for example, SS/PBCH blocks) in measurement gaps.

<FIG> is a diagram to show an exemplary functional structure of a user terminal. 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.

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 measurement section <NUM> may measure synchronization signal blocks in measurement gaps.

The control section <NUM> may also control the timing at a granularity finer than <NUM> millisecond, based on configuration information (for example, MG configurations) about the timing offsets of measurement gaps (for example, MG timing offsets).

Also, the control section <NUM> may determine the timing for measurements based on information (for example, SMTC) about the timing for measuring synchronization signal blocks (for example, the SMTC window). Also, the start of measurement timings may be after retuning (for example, RF retuning) in the receiving section at the top of a measurement gap (for example, transmitting/receiving sections <NUM>).

Also, the granularity may be based on the slot duration of the serving cell.

Also, the control section <NUM> may use, as an offset, a value given by adding a given additional offset (for example, RF retuning time, slot duration) to the value indicated in the configuration information.

Also, in the configuration information, an additional offset for the measurement gap timing for a frequency (for example, FR <NUM>) lower than a given frequency may be different from an additional offset for the measurement gap timing for a frequency (for example, FR <NUM>) higher than the given frequency.

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 two 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 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. 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.

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 convey 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 contiguous 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 contiguous 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 region 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 (for example, RRC (Radio Resource Control) signaling, broadcast information (the master information block (MIB), system information blocks (SIBs) and so on), MAC (Medium Access Control) signaling and so on), 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.

Claim 1:
A terminal (<NUM>) comprising:
a receiving section (<NUM>) configured to receive, via higher layer signaling,
first information indicating a gap offset in subframe units related to a measurement gap, MG, and
second information indicating a shift time shorter than one subframe and related to the MG; and
a control section (<NUM>) configured to determine a timing of the MG based on the gap offset and the shift time.