JPWO2018158925A1 - User terminal and wireless communication method - Google Patents

Abstract

Even when the uplink data and the demodulation reference signal are transmitted using the short TTI, in order to appropriately control the UL transmission, in a plurality of cells, the UL signal and the UL reference used for demodulation of the UL signal are used. A transmission unit that transmits a signal using the same transmission time interval or a different transmission time interval, and a control unit that controls generation and / or transmission power of the UL signal and the UL reference signal, is provided in a user terminal, The control unit applies a predetermined modulation scheme to the UL signal and / or the same transmission power to the UL signal and the UL reference signal.

Description

  The present invention relates to a user terminal and a wireless communication method in a next-generation mobile communication system.

  In a UMTS (Universal Mobile Telecommunications System) network, Long Term Evolution (LTE: Long Term Evolution) has been specified for the purpose of higher data rate, lower delay, and the like (Non-Patent Document 1). For the purpose of further increasing the bandwidth and speed from LTE, successor systems to LTE (for example, LTE-A (LTE-Advanced), FRA (Future Radio Access), 4G, 5G, 5G + (plus), NR ( New RAT), LTE Rel. 14, 15-, etc.) are also being studied.

  In an existing LTE system (for example, LTE Rel. 10 or later), a carrier aggregation (CA: Carrier Aggregation) that integrates a plurality of carriers (component carriers (CC: Component Carrier) and cells) is introduced to widen the bandwidth. Have been. Each carrier is LTE Rel. Eight system bands are configured as one unit. In CA, a plurality of CCs of the same radio base station (eNB: eNodeB) are set in a user terminal (UE: User Equipment).

  In addition, in existing LTE systems (for example, LTE Rel. 12 or later), dual connectivity (DC: Dual Connectivity) in which a plurality of cell groups (CG: Cell Groups) of different radio base stations are set in a user terminal is also introduced. ing. Each cell group includes at least one carrier (CC, cell). Since a plurality of carriers of different radio base stations are integrated, DC is also called inter-base station CA (Inter-eNB CA) or the like.

  In an existing LTE system (for example, LTE Rel. 13 or earlier), downlink (DL) and / or uplink (UL) communication is performed using a transmission time interval (TTI) of 1 ms. Is performed. The 1 ms TTI is a transmission time unit of one channel-encoded data packet, and is a processing unit such as scheduling, link adaptation, and retransmission control (HARQ-ACK: Hybrid Automatic Repeat reQuest-Acknowledge). The 1 ms TTI is also called a subframe, a subframe length, or the like.

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

  Future wireless communication systems (eg, 5G, NR, etc.) are expected to implement various wireless communication services to satisfy different requirements (eg, ultra-high speed, large capacity, ultra-low delay, etc.). ing. For example, provision of wireless communication services called eMBB (enhanced Mobile Broad Band), mMTC (massive Machine Type Communication), and URLLC (Ultra Reliable and Low Latency Communications) has been studied.

  By the way, in a future wireless communication system, a TTI (for example, a short TTI (short TTI, sTTI, and the like) shorter than the TTI of 1 ms in the existing LTE (for example, LTE Rel. )) Is being considered.

  When the UE transmits a UL shared channel (eg, UL data) in a short TTI (sTTI), a demodulation reference signal (DMRS: DMRS :) used for demodulating data symbols at least one before, during, and after the sTTI. It is preferable to adopt a configuration for transmitting a DeModulation Reference Signal).

  Also, when transmitting UL data using sTTI, depending on the configuration of sTTI, it is assumed that UL data and DMRS are transmitted discontinuously in the time direction (for example, different sTTIs). However, in existing LTE, there is no regulation regarding sTTI, and thus there is a problem how to control transmission of UL data and DMRS corresponding to the UL data.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has a user terminal and a radio communication method capable of appropriately controlling UL transmission even when transmitting uplink data and a demodulation reference signal using a short TTI. One of the purposes is to provide.

  One aspect of the user terminal of the present invention, in a plurality of cells, a UL signal and a UL reference signal used for demodulation of the UL signal, a transmission unit that transmits using the same transmission time interval or different transmission time intervals, A control unit that controls generation and / or transmission power of the UL signal and the UL reference signal, wherein the control unit performs a predetermined modulation scheme on the UL signal and / or the UL signal and The same transmission power is applied to UL reference signals.

  According to the present invention, it is possible to appropriately control UL transmission even when transmitting uplink data and a demodulation reference signal using the short TTI.

1A and 1B are diagrams illustrating an example of the configuration of the sTTI. FIG. 9 is a diagram illustrating an example of UL transmission using a plurality of CCs to which sTTI is applied. FIG. 3A and FIG. 3B are diagrams illustrating an example of allocation of DMRS and UL data in sTTI. 4A and 4B are diagrams illustrating an example of setting of transmission power of DMRS and UL data. 5A and 5B are diagrams illustrating another example of the setting of the transmission power of the DMRS and the UL data. 6A and 6B are diagrams illustrating an example of a PHR report in UL transmission using sTTI. 7A and 7B are diagrams illustrating another example of setting the transmission power of the DMRS and the UL data. FIG. 11 is a diagram illustrating another example of UL transmission using a plurality of CCs to which sTTI is applied. 1 is a schematic configuration diagram illustrating an example of a schematic configuration of a wireless communication system according to the present embodiment. FIG. 3 is a diagram illustrating an example of an overall configuration of a wireless base station according to the present embodiment. FIG. 3 is a diagram illustrating an example of a functional configuration of a wireless base station according to the present embodiment. FIG. 3 is a diagram illustrating an example of an overall configuration of a user terminal according to the present embodiment. FIG. 3 is a diagram illustrating an example of a functional configuration of a user terminal according to the present embodiment. FIG. 2 is a diagram illustrating an example of a hardware configuration of a radio base station and a user terminal according to an embodiment of the present invention.

  In LTE, as a method of reducing communication delay, signal transmission and reception is performed by introducing a shortened TTI (sTTI: shortened TTI) having a shorter period than an existing transmission time interval (TTI: Transmission Time Interval) (for example, subframe (1 ms)). Controlling is being considered. Also, in 5G / NR, it is considered that UEs use different services at the same time. In this case, it is considered to change the TTI length depending on the service.

  Note that the TTI may represent a time unit for transmitting and receiving a transport block, a code block, and / or a code word of transmission / reception data. When a TTI is given, a time interval (the number of symbols) in which a transport block, a code block, and / or a code word of data are actually mapped may be shorter than the TTI.

  For example, when the TTI is composed of a predetermined number of symbols (for example, 14 symbols), a transport block, a code block, and / or a codeword of transmission / reception data may be one to a predetermined number of symbol intervals. Can be transmitted and received. When the number of symbols for transmitting and receiving transport blocks, code blocks, and / or codewords of transmitted / received data is smaller than the number of symbols constituting the TTI, a symbol to which data is not mapped in the TTI includes a reference signal, a control signal, and the like. Can be mapped.

  As described above, in both LTE and NR, the UE may transmit and / or receive using both the long TTI and the short TTI.

  The long TTI is a TTI having a longer time length than the short TTI (for example, a TTI having the same 1 ms time length as an existing subframe (TTI in LTE Rel. 8-13)), and is usually a TTI (nTTI: normal). TTI), 1 ms TTI, normal subframe, long subframe, subframe, slot, long slot, etc. Also, in NR, a long TTI may be referred to as a lower (smaller) subcarrier spacing (eg, 15 kHz) TTI.

  The long TTI has a time length of 1 ms, for example, and is configured to include 14 symbols (in the case of a normal cyclic prefix (CP)) or 12 symbols (in the case of an extended CP). It is considered that long TTI is suitable for services such as eMBB and mMTC in which delay reduction is not strictly required.

  In existing LTE (for example, LTE Rel. 8-13), as channels transmitted and / or received in a TTI (subframe), a downlink control channel (PDCCH: Physical Downlink Control Channel) and a downlink data channel (PDSCH: Physical) A Downlink Shared Channel, an Uplink Control Channel (PUCCH: Physical Uplink Control Channel), a Downlink Data Channel (PUSCH: Physical Uplink Shared Channel), and the like are used.

  The short TTI is a TTI having a shorter time length than the long TTI, and may be called a shortened TTI, a partial TTI (partial or fractional TTI), a shortened subframe, a partial subframe, a minislot, a subslot, and the like. Also, in NR, a short TTI may be referred to as a higher (larger) subcarrier spacing (eg, 60 kHz) TTI.

  The short TTI includes, for example, a smaller number of symbols (for example, two symbols, seven symbols, and the like) than the long TTI, and the time length (symbol length) of each symbol is the same as the long TTI (for example, 66.7 μs). You may. Alternatively, the short TTI may be composed of the same number of symbols as the long TTI, and the symbol length of each symbol may be shorter than the long TTI.

  FIG. 1 shows an example of the configuration of the short TTI. FIG. 1 shows a case in which one subframe (14 OFDM symbols) is divided into predetermined sections and a plurality of short TTIs are set. In FIG. 1A, one subframe is divided into 3, 2, 2, 2, 2, and 3 symbols, and short TTIs (sTTI # 0 to # 5) are set. sTTI # 0 and # 5 are composed of 3 symbols, and sTTI # 1 to # 4 are composed of 2 symbols. Such a configuration is also referred to as a two-symbol sTTI (2-OS sTTI, 2OS (OFDM Symbol)). Alternatively, they may be called sTTI configuration 1, sTTI format 1, sTTI configuration 1, and so on.

  In FIG. 1B, one subframe is divided into 7, 7 symbols, and a short TTI (sTTI # 0- # 1) is set. sTTI # 0 and # 1 are composed of 7 symbols. Such a configuration is also referred to as a 7-symbol sTTI (7-OS sTTI, 7OS). Alternatively, it may be called sTTI configuration 2, sTTI format 2, sTTI configuration 2, and so on.

  When the short TTI is used, a time margin for processing (eg, encoding, decoding, and the like) in the UE and / or the base station increases, and processing delay can be reduced. When the short TTI is used, the number of UEs that can be accommodated per unit time (for example, 1 ms) can be increased. The short TTI is considered to be suitable for services that require strict delay reduction, such as URLLC.

  The UE for which the short TTI is set uses a channel in a time unit shorter than the existing data and control channels. In LTE, NR, and the like, shortened downlink control channels (sPDCCH: shortened PDCCH), shortened downlink data channels (sPDSCH: shortened PDSCH), and shortened uplink control channels (sPUCCH: shortened) are transmitted and / or received in a short TTI. PUCCH), a shortened downlink data channel (sPUSCH: shortened PUSCH), and the like are being studied.

  By the way, it is considered that the data symbol of the sPUSCH is mapped only within one short TTI. It is preferable that a demodulation reference signal (DMRS: DeModulation Reference Signal) used for demodulating data symbols is transmitted before, during, and / or after the short TTI. That is, the data symbols and the DMRS may be arranged by time division multiplexing (TDM). Further, the data symbol and the DMRS may be mapped to radio resources that are continuous in time and / or frequency, or may be mapped to radio resources that are not continuous (non-adjacent).

  As a multiplexing method of DMRS when using the short TTI, it is conceivable to use interleaved frequency division multiplexing (IFDMA). IFDMA is a radio access scheme having both the characteristics of multicarrier and single carrier.

  Specifically, in IFDMA, multiplexing of DMRS can be performed by applying unequal frequency resources and target reception power among a plurality of UEs. The unequal frequency resources among a plurality of UEs include, for example, partially overlapping frequency resources, and frequency resources in which at least one of the lower end and the upper end of the allocated frequency resources is different.

  In addition, application of a cyclic shift (CS) as a multiplexing method of DMRS when using the short TTI is being studied. In this case, orthogonality between UEs can be ensured by applying the same frequency resource and the same target reception power to a plurality of UEs. Note that multiplexing of DMRS may be controlled by combining IFDMA and cyclic shift.

  When performing UL transmission (for example, HARQ-ACK transmission for DL data and / or UL data transmission for UL grant) using the short TTI, the UE transmits the UL transmission at a predetermined timing. For example, when the short TTI is a two-symbol TTI (2OS) (see FIG. 1A), UL transmission is performed after a first timing from the DL signal reception timing (for example, sTTI # n). The first timing may be, for example, k × sTTI (2OS). In this case, the UE performs UL transmission after n + ksTTI. As the value of k, for example, 4, 6, 8, 10, 12, and the like can be considered. Different k values may be set according to the processing capability of the user terminal. In this case, it is desirable that the user terminal reports to the wireless communication base station in advance the terminal capability information that allows the value of k that can be set based on its own processing capability to be recognized.

  When the short TTI is a 7-symbol TTI (7OS) (see FIG. 1B), UL transmission is performed after a second timing from the DL signal reception timing (for example, sTTI # n). The second timing may be, for example, 4 × sTTI (7OS). In this case, the UE performs UL transmission after n + 4s TTI (two subframes). As described above, the UL transmission timing for the DL signal may be set according to the number of symbols constituting the sTTI. Note that the UL transmission timing is not limited to the value described above.

  In a future wireless communication system, it is assumed that UL transmission is performed using a plurality of cells including at least a cell to which the short TTI is applied. As a form of performing UL transmission using a plurality of cells (CC), carrier aggregation (CA) and / or dual connectivity (DC) are assumed.

  In this case, it is assumed that the TTI length of the UL CC used in CA and / or DC is set differently. For example, in CA, when a group for controlling PUCCH transmission (PUCCH group) is set, the same TTI length is set for CCs in the same group, and different TTI lengths are set for CCs in different groups. Conceivable. In DC, different TTI lengths may be set for each of the master cell group (MCG) and the secondary cell group (SCG).

  For example, in the first UL CC # 1, a first TTI length (for example, 1 ms) is applied, and in the second UL CC # 2, a second TTI length (for example, 2OS sTTI) is applied. Alternatively, a first TTI length (for example, 7OS sTTI) is applied to the first UL CC # 1, and a second TTI length (for example, 2OS sTTI) is applied to the second UL CC # 2.

  Also, in DMRS multiplexing based on IFDMA, amplifying (power boosting) the DMRS power (EPRE: Energy Per Resource Element) in order to make the transmission power of the DMRS symbol equal to the transmission power of the data symbol is being studied. As described above, it is conceivable to set the same transmission power for the UL data and the DMRS for demodulating the UL data.

  However, when performing UL transmission using a short TTI, depending on the configuration of the short TTI, it is assumed that the UL data and the DMRS are allocated discontinuously (for example, different sTTIs) in the time direction. When performing UL transmission using a plurality of cells, in a certain transmission period (for example, a predetermined symbol or a predetermined sTTI), the total value of the UL transmission power of the UE requested from the radio base station exceeds a predetermined value, and It is conceivable that transmission power is limited (power limited). In this case, it may be difficult to apply the same transmission power to UL data and DMRS transmitted in discontinuous or different sTTIs.

  In FIG. 2, two CCs (CC # 1 and CC # 2) are set for DL transmission and UL transmission, respectively, and UL transmission (HARQ-ACK or UL) for a DL signal (DL data or UL grant) is set in each CC. Data) is performed at a predetermined timing. FIG. 2 shows a case where sTTI having the same TTI length is applied to each of the DL and UL CCs. Here, a configuration (2OS sTTI) in which one subframe (14 OFDM symbols) is divided into 3, 2, 2, 2, 2, and 3 symbols is shown.

  FIG. 2 shows a case where a UL signal corresponding to the DL signal transmitted by sTTI # N is transmitted after N + k × sTTI (2OS) (here, k = 6). For example, with respect to a DL signal (for example, UL grant) of sTTI # 2 of CC # 1, UL transmission using UL sTTI # 8 of CC # 1 after 6 × sTTI (2OS) (for example, UL data Transmission). Here, a case is shown in which a DL signal is allocated to two symbols constituting sTTI # 8, and a DMRS corresponding to the DL signal is transmitted using the symbol of the immediately preceding sTTI # 7. Although FIG. 2 shows a case where k = 6, the value of k is not limited to this.

  In addition, with respect to the DL signal (for example, UL grant) of sTTI # 1 of CC # 2, UL transmission (for example, UL data) using the sTTI # 7 of UL of CC # 2 after 6 × sTTI (2OS) Transmission). Here, a case is shown where a DMRS is assigned to one of two symbols constituting sTTI # 7 and a DL signal is assigned to the other. That is, the case where the DMRS corresponding to the DL signal is transmitted in the same sTTI is shown.

  In FIG. 2, UL data is transmitted in different symbols (or different sTTIs) in different CCs, but DMRS is transmitted in the same symbol (or the same sTTI). In this case, since the UL data is transmitted by one CC, the UE can transmit each UL data with the required power set from the radio base station. On the other hand, since the DMRS is transmitted from different CCs in duplicate, the UE may not be able to transmit the DMRS using the required power set from the base station (power limited). Control of transmission power (setting of transmission power and / or determination of power limited, etc.) may be performed on a symbol basis or on an sTTI basis.

  As described above, when the DMRS and the UL data are transmitted in different sTTIs, there is a possibility that one of the UL signal and the DMRS used for demodulating the UL signal is power-limited in a predetermined CC. In such a case, even if the same required power is set for the DMRS and the UL data (for example, the DMRS and the UL data of CC # 1), the UE cannot apply the same transmission power to the DMRS and the UL data. As a result, the radio base station cannot properly perform the UL data reception process (for example, the demodulation process based on the DMRS), and the communication quality may be degraded.

  When the UL signal and the UL reference signal used for demodulation of the UL signal are transmitted discontinuously (for example, in different sTTIs), the present inventors transmit only one transmission due to the occurrence of power limited or the like. Focusing on the point that power may be limited, applying a predetermined modulation scheme to the UL signal and / or controlling to apply the same transmission power to the UL signal and the UL reference signal. Inspired.

  As one aspect of the present embodiment, the transmission is controlled without allowing only one of the transmission of the UL signal and the transmission of the UL reference signal corresponding to the UL signal between a plurality of cells. Alternatively, as another aspect of the present embodiment, transmission is controlled by allowing only one of transmission of a UL signal and transmission of a UL reference signal corresponding to the UL signal to be overlapped between a plurality of cells.

  Further, as another aspect of the present embodiment, demodulation using a UL reference signal across subframes (corss-subframe DMRS demodulation) and / or demodulation using a UL reference signal across slots (cross-slot DMRS demodulation). ) To control the transmission without allowing. Alternatively, as another aspect of the present embodiment, transmission is controlled by allowing demodulation using a UL reference signal that crosses a subframe and / or demodulation using a UL reference signal that crosses a slot.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the present embodiment, the short TTI (sTTI) may have any configuration as long as the time length is shorter than the long TTI (1 ms). In the following, as an example, an example will be described in which the short TTI is configured with a smaller number of symbols than the long TTI, and each symbol has the same symbol length as the long TTI. Can be applied as appropriate. Further, each of the following embodiments may be applied alone or in combination.

  Further, in the following description, a case will be described as an example in which a UL signal is a UL grant (DCI) instructing transmission of sPUSCH (for example, UL data) and a UL signal for the DL signal is sPUSCH (UL data). However, the present embodiment is not limited to this. For example, the same applies to a case where the DL signal is sPDSCH (for example, DL data) and the UL signal is HARQ-ACK (for example, sPUCCH) for the DL data. Alternatively, the present invention can be similarly applied to any signal that performs demodulation using a reference signal.

  Further, in the following description, CA and / or DC are assumed as communication using a plurality of UL CCs, but the communication mode to which the present embodiment can be applied is not limited to this. Any communication that uses a plurality of CCs can be applied. In the following description, a case where two cells (CCs) are used is shown, but the number of available CCs is not limited to two, and may be three or more. Further, the present invention can be applied to a case where a single CC is used.

(First aspect)
In the first aspect, a case where only one of UL data and a UL reference signal (DMRS) used for demodulation of the UL data among a plurality of UL CCs is not allowed to overlap (overlap) with a UL signal of another CC. Will be described.

  When a DMRS used for demodulation of UL data in a predetermined cell (CC) overlaps with a UL signal of another cell, the user terminal assumes that the UL data (allocation symbol of UL data) also overlaps with a UL signal of another cell. (See FIG. 3A). Alternatively, when the DMRS used for demodulating UL data in a predetermined cell does not overlap with the UL signal of another cell, it is assumed that the UL data (allocation symbol of UL data) also does not overlap with the UL signal of another cell (see FIG. 3B). ).

  The user terminal can acquire, from the radio base station, information on the position where the DMRS is arranged (allocation symbol of the DMRS). For example, when sTTI is used in UL, the radio base station uses downlink control information and / or higher layer signaling (for example, RRC signaling, broadcast information, etc.) with information on the DMRS allocation pattern in each sTTI. To notify the user terminal.

  FIG. 3 shows a case in which one subframe is divided into 3, 2, 2, 2, 2, and 3 symbols in CC # 1 and CC # 2 to form an sTTI (2OS sTTI). FIG. 3A shows a case where DMRS is allocated to some symbols (here, the first half symbol) of sTTI # 1 and UL data is allocated to two symbols of sTTI # 2 in CC # 1. In this case, the radio base station demodulates sTTI # 2 UL data using the sTTI # 1 DMRS.

  In CC # 2, DMRS is allocated to some symbols (here, the first half symbols) of sTTI # 1. In this case, the DMRS overlaps with the DMRS of sTTI # 1 of CC # 1. Therefore, allocation is controlled so that the UL data of CC # 1 also overlaps with the UL signal of CC # 2 (here, UL data). When one of the UL data and DMRS transmitted by CC # 1 overlaps with the UL signal of another cell, the user terminal can assume that the other of the UL data and DMRS also overlaps with the UL signal of another cell.

  As shown in FIG. 3A, when the UL data and the DMRS overlap with the transmission of the UL signal of another cell, one or both of the UL data and the DMRS may be power limited. Power limited means that UL transmissions overlap in a plurality of cells in a predetermined period, and the required power of each UL signal exceeds an allowable maximum power (Pcmax) set in the user terminal.

  When power limited occurs, the user terminal performs power scaling (reduction in transmission power) on transmission power of a predetermined UL signal or drops a predetermined UL signal. In FIG. 3A, when at least one of UL data and DMRS becomes power limited, the user terminal may perform power scaling based on a predetermined criterion. For example, the user terminal applies power scaling to the UL data and the DMRS corresponding to the UL data under the same condition (rule). Thus, even when only one of the UL data and the DMRS is power limited, the UL data and the DMRS can be transmitted with the same transmission power.

  In FIG. 3B, DMRS and UL data are allocated to sTTI # 2 in CC # 1. The radio base station demodulates the same sTTI # 2 UL data using the sTTI # 2 DMRS. In CC # 2, DMRS and UL data are allocated to sTTI # 1. In this case, since the DMRS of CC # 1 does not overlap with the UL signal of CC # 2, allocation is controlled so that the UL data of CC # 1 does not overlap with the UL signal of CC # 2. When one of the UL data and DMRS transmitted by CC # 1 does not overlap with the UL signal of another cell, the user terminal can assume that the other of the UL data and DMRS does not overlap with the UL signal of another cell.

  As described above, when performing UL transmission using a plurality of cells, control is performed so that only one of the UL data and the DMRS that demodulates the UL data does not overlap with the UL transmission of another cell. As a result, even when DMRS and UL data are transmitted non-continuously (for example, in different sTTIs), it is possible to suppress that only one of them overlaps and becomes power limited. As a result, the user terminal can appropriately set the transmission power of the DMRS and the UL data (for example, the same), and thus can appropriately perform the demodulation of the UL data in the wireless base station.

(Second aspect)
In the second mode, a case will be described in which only one of UL data and a DMRS used for demodulation of the UL data is allowed to overlap (overlap) with a UL signal of another CC among a plurality of UL CCs.

  When a DMRS used for demodulation of UL data in a predetermined cell overlaps with a UL signal of another cell, the user terminal assumes that the UL data may or may not overlap with a UL signal of another cell. When the DMRS used for demodulating UL data in a predetermined cell does not overlap with the UL signal of another cell, it is assumed that the UL data may or may not overlap with the UL signal of another cell.

  In this way, flexible allocation can be performed by controlling the allocation of UL data and DMRS of a predetermined cell without considering the allocation of UL signals of other cells. On the other hand, when only one transmission of the UL data and the DMRS overlaps with the UL transmission of another cell, there is a possibility that only one of the transmissions becomes power limited.

  Therefore, in the second aspect, the user terminal applies a predetermined modulation scheme to UL data (sPUSCH) and / or applies the same transmission power to UL data and DMRS. One transmission power (eg, the lower transmission power) is also applied to the other transmission.

<Application of predetermined modulation method>
The user terminal applies transport shift keying (eg, QPSK) to UL data (sPUSCH). In the existing LTE system, QPSK, 16QAM, and 64QAM are supported as modulation schemes applied to UL data (PUSCH). 16QAM and 64QAM are systems that perform modulation using amplitude and phase, and QPSK is a system that performs modulation using phase. Therefore, by restricting the modulation scheme applied to UL data to phase shift keying, even when different transmission powers are applied to UL data and DMRS, the radio base station can appropriately perform demodulation of UL data. .

  The user terminal can apply different transmission power to DMRS and UL data assigned to non-consecutive cells (for example, different sTTIs) in a predetermined cell (see FIG. 4). The radio base station may instruct the user terminal to apply a predetermined modulation scheme (for example, QPSK) to UL data that is discontinuously assigned to the DMRS. For example, the radio base station notifies the user terminal of downlink control information (UL grant) for instructing UL data transmission, including information for instructing a predetermined modulation scheme. Alternatively, when the DMRS and the UL data are non-consecutively allocated, the user terminal may perform control such that a predetermined modulation scheme is applied to the UL data.

  FIG. 4A shows a case where DMRS is assigned to a part of sTTI # 1 of CC # 1 and UL data is assigned to sTTI # 3, and DMRS and UL data are assigned to different symbols of sTTI # 1 of CC # 2. . In this case, transmission of DMRS of sTTI # 1 is duplicated between CC # 1 and CC # 2. Therefore, there is a possibility that the total value of the required power of each DMRS exceeds the maximum power (Pcmax) allowed for the user terminal and becomes power limited.

  In this case, the user terminal can apply power scaling (reduction in transmission power) only to the DMRS, and transmit UL data transmission by applying the required power (without performing power scaling). Further, the user terminal applies a predetermined modulation scheme (for example, QPSK) to UL data.

  FIG. 4B shows a case where DMRS is assigned to a part of sTTI # 1 of CC # 1 and UL data is assigned to sTTI # 2, and DMRS and UL data are assigned to different symbols of sTTI # 2 of CC # 2. . In this case, sTTI # 2 UL transmission (here, DMRS, UL data, and UL data) overlaps between CC # 1 and CC # 2. Therefore, in sTTI # 2, the total value of the required power of the UL signal may exceed the maximum power (Pcmax) allowed for the user terminal and become power limited.

  In this case, the user terminal applies power scaling (reduction in transmission power) to DMRS and UL data that overlap between CCs, and applies power scaling to DMRS of non-overlapping DMRS (sTTI # 1 of CC # 1). You can send without. Further, the user terminal applies a predetermined modulation scheme (for example, QPSK) to UL data.

  As described above, a predetermined modulation scheme is applied to UL data, and different transmission powers are applied to DMRS and UL data. This makes it possible to flexibly set the transmission timing of the UL signal in each cell when performing UL transmission in a plurality of cells. Further, even when different transmission powers are set for the DMRS and the UL data, the radio base station can appropriately demodulate the UL data.

  Also, when power limited occurs due to simultaneous transmission (overlap) of UL signals between a plurality of cells, the user terminal independently applies power scaling to UL data and the DMRS corresponding to the UL data. Is also good. In this case, the user terminal can control power scaling by setting the same priority to DMRS and UL data (sPUSCH).

  For example, when transmission of DMRS and UL data is overlapped between different cells and becomes power limited, the user terminal adjusts transmission power by applying power scaling to the DMRS and UL data at the same rate (FIG. 5A). reference). FIG. 5A shows a case where power scaling is applied to DMRS and UL data transmitted in sTTI # 2 of each cell at the same rate. On the other hand, power scaling is not applied to DMRS (here, sTTI # 2 of CC # 1) transmitted only in one cell.

  The radio base station demodulates UL data to which power scaling is applied by using the DMRS to which power scaling is not applied in CC # 1. In this case, since a predetermined modulation method is applied to the UL data, the radio base station can appropriately demodulate the UL data even when the transmission power of the DMRS is different from that of the UL data. Further, the radio base station uses the DMRS to which power scaling is applied in CC # 2, and demodulates UL data to which power scaling is applied in the same manner as the DMRS.

  Alternatively, the user terminal may control power scaling by setting different priorities for DMRS and UL data. For example, power scaling is performed by setting a higher priority for one transmission of DMRS and UL data than for the other transmission. In this case, it is possible to adopt a configuration in which the power reduced by the power scaling is reduced or the power scaling is not applied to the transmission with the higher priority set. This makes it possible to selectively set the transmission power of a signal whose priority is set high to be high.

  FIG. 5B shows a case where the DMRS and the UL data transmitted in sTTI # 2 of each cell are set to a higher priority than the UL data for the DMRS to control power scaling. In a symbol in which the DMRS and the UL data transmission overlap, power scaling is applied so that the transmission power of UL data becomes smaller (or power scaling is not applied to the DMRS). For symbols in which transmission of UL data overlaps, power scaling may be applied in the same manner. When transmission is performed by a modulation and coding scheme with a low operating SNR, improvement of channel estimation accuracy is more likely to contribute to performance improvement than securing of data power. Demodulation performance can be improved.

  The radio base station demodulates UL data to which power scaling is applied by using the DMRS to which power scaling is not applied in CC # 1. Further, the radio base station demodulates UL data to which power scaling is applied by using a DMRS to which power scaling is not applied (or a decrease in power is smaller than UL data) in CC # 2.

  When the priority is set for the power scaling, the priority may be set in consideration of the cell index and the like in addition to the signal type.

  Also, the user terminal can calculate a Power Headroom Report (PHR) using DMRS and / or UL data (sPUSCH).

  The PHR is a report that a user terminal feeds back to a device on the network side (for example, a radio base station), and includes information on an uplink power margin (PH: Power Headroom) for each serving cell. The radio base station can dynamically control the uplink transmission power of the user terminal based on the PHR reported from the user terminal.

  In existing LTE (eg, LTE Rel. 13), a user terminal transmits a PHR by MAC signaling using a PUSCH. Specifically, the PHR is configured by a PHR MAC CE (Control Element) included in a MAC PDU (Protocol Data Unit). At present, two types of PH (type 1 PH, type 2 PH) are defined. The type 1 PH is a PH when only the power of the PUSCH is considered, and the type 2 PH is a PH when both the power of the PUSCH and the PUCCH are considered. The PH information may be a PH value or an index associated with a PH value (or level).

  The user terminal may calculate the PHR based on one of the DMRS and the UL data. When performing power scaling, it is preferable to calculate PHR using DMRS or UL data before power scaling. This is because if the required transmission power exceeds the maximum transmission power (it is power limited), the value of PHR indicates a negative (dB) value, so it is determined whether the user terminal is power limited or not. This is because the base station can be determined.

  For example, when performing power scaling as illustrated in FIG. 5A, the user terminal calculates a PHR based on the DMRS to which power scaling is not applied (sTTI # 1 DMRS) and reports the PHR to the radio base station (see FIG. 6A, See FIG. 6B). Alternatively, the user terminal calculates a PHR based on UL data (sTTI # 2 UL data) before applying power scaling and reports the PHR to the radio base station (see FIGS. 6A and 6B). When different transmission powers are set for a plurality of data, the PHR may be calculated based on one of them, or the PHR may be calculated and reported based on a plurality of UL data.

<Transmission power control>
The user terminal may apply the power set to one of the UL data and the DMRS to the other transmission. For example, of the transmission power set for the UL data and the DMRS, the smaller transmission power is applied as the actual transmission power of the UL data and the DMRS. When power P # 1 is set for DMRS and power P # 2 is set for UL data, the user terminal uses one of the powers # 1 and # 2 (for example, the smaller power). Is selected and applied to both UL data and DMRS to perform transmission.

  The powers P # 1 and P # 2 may be values that reflect (reflect) scheduling information, TPC commands, power scaling factors, and the like notified from the radio base station. For example, the powers P # 1 and P # 2 may be required powers required by the radio base station for DMRS and UL data, or may be powers obtained by applying a TPC command to the required powers. However, the power may be power in consideration of power scaling.

  In FIG. 7A, DMRS is assigned to a part of sTTI # 1 in CC # 1, and UL data is assigned to sTTI # 2. In CC # 2, DMRS and UL data are allocated to sTTI # 1. In this case, DMRS overlaps in sTTI # 1. Therefore, the transmission power of the DMRS of each CC is set to a value in consideration of the power limited (or power reduced from required power by power scaling). On the other hand, since the UL data does not overlap between CCs, a high transmission power is set. In this case, the user terminal controls transmission by applying the power P # 1 set in the DMRS to the power P # 2 of UL data.

  In FIG. 7B, DMRS is allocated to a part of sTTI # 1 in CC # 1, and UL data is allocated to sTTI # 2. In CC # 2, DMRS and UL data are allocated to sTTI # 2. In this case, in sTTI # 2, the DMRS, UL data, and UL data overlap. Therefore, the transmission power of the DMRS and UL data of each CC is set to a value in consideration of power limited (or power reduced from required power by power scaling). On the other hand, since the DMRS of sTTI # 1 does not overlap between CCs, a high transmission power is set. In this case, the user terminal controls transmission by applying the power P # 2 set in the UL data of sTTI # 2 also to the power P # 1 of the DMRS of sTTI # 1.

  As described above, one of the powers of the UL data and the DMRS is selected and used as the actual transmission power of the UL data and the DMRS. The same transmission power is applied even when any of the transmissions is power limited. Can be. Further, the modulation method of UL data can be used without being limited to a predetermined modulation method (for example, QPSK).

(Third aspect)
In the first and second aspects, the case where the same TTI length (two symbols sTTI) is applied to a plurality of CCs has been described. However, the case where different TTI lengths are applied to a plurality of CCs may be considered.

  FIG. 8 shows a case where signals are transmitted and received using 2CCs to which different TTI lengths are applied. In CC # 1, 2OS sTTI is applied in UL and DL, and in CC # 2, 7OS sTTI is applied in UL and DL. In CC # 1, one subframe (14 OFDM symbols) is divided into 3, 2, 2, 2, 2, and 3 symbols, and a section in which the sTTI is 3 symbols (2OS is composed of 3 symbols) is included. It is.

  FIG. 8 illustrates a case where the transmission timing of the UL signal (for example, UL data) with respect to the DL signal (for example, UL grant) in CC # 1 is N + 6s TTI (2OS). Also, a case is shown where the transmission timing of the UL signal with respect to the DL signal in CC # 2 is n + 4s TTI (7OS). Thus, the transmission timing of the UL signal with respect to the DL signal can be set according to the TTI length. Note that the transmission timing of the UL signal with respect to the DL signal is not limited to this.

  When transmitting UL data using an sTTI (for example, 2OS sTTI), the UL data and the DMRS for demodulating the UL data may be arranged non-contiguously (for example, in different sTTIs). For example, when transmitting UL data using the sTTI at the head of the slot (for example, sTTI # 15 (2OS) in FIG. 8), the sTTI prior to the sTTI (for example, sTTI # 14 (2OS) in FIG. 8). It is conceivable to demodulate UL data using the DMRS transmitted to the UE. In this case, DMRS and UL data are arranged across slots.

  In FIG. 8, in CC # 2, allocation of UL data is controlled in units of 7 symbols (slots). Therefore, as shown in FIG. 8, UL transmission may not be performed in a certain slot (for example, sTTI # 4 (7OS)), and UL transmission may be performed in the next slot (for example, sTTI # 5 (7OS)). Here, sTTI # 14 (2OS) of CC # 1 overlaps with sTTI # 4 (7OS) of CC # 2, and sTTI # 15 (2OS) of CC # 1 and sTTI # 5 (7OS) of CC # 2. Duplicate.

  In this case, in CC # 1, UL data (sTTI # 15 (2OS)) overlapping with the UL signal of CC # 2 is power limited, but DMRS (sTTI # 14 (2OS)) used for demodulation of the UL data. ) May not be power limited. In this case, there is a possibility that transmission cannot be performed with the same transmission power between the UL data and the DMRS. As a result, demodulation of UL data using DMRS cannot be performed properly in the wireless base station, and communication quality may be degraded.

  When transmitting UL data using sTTI (for example, 2OS sTTI), DMRS and UL data may be arranged across subframes. Therefore, when UL transmission is performed using CC # 1 to which a predetermined TTI length (for example, 2OS) is applied and CC # 2 to which a subframe (1 ms) is applied, UL data is transmitted in the same manner as in FIG. One of the DMRSs may be power limited.

  Therefore, in the third mode, transmission is controlled without allowing demodulation using DMRS across subframes and / or slots. That is, control is performed so that UL data and DMRS used for demodulation of the UL data are not arranged in different subframes and / or different slots. The user terminal assumes that the UL data and the DMRS used for demodulation of the UL data are not arranged in different subframes and / or different slots, and controls transmission power control of the DMRS used for demodulation of the UL data and the UL data. Perform room calculations, etc.

  In this case, the transmission power of the UL data and / or the DMRS may be set without changing in at least one period of the subframe and sTTI (for example, slot (7OS sTTI) and 2OS sTTI). For example, by using a configuration in which power is not changed during a subframe and sTTI, the same transmission power is set for discontinuous DMRS and UL data.

  Also, by allocating DMRS and UL data so as not to span subframes and / or slots, and by not changing the transmission power within the subframe and / or sTTI, the presence or absence of power limited can be determined by the DMRS and UL data. Can be common to both. When power limited occurs in DMRS and UL data, power scaling under the same condition may be applied to the DMRS and UL data.

(Fourth aspect)
In the fourth mode, transmission is controlled by allowing demodulation using DMRS across subframes and / or slots. That is, it is allowed to arrange UL data and DMRS used for demodulation of the UL data in different subframes and / or different slots.

  As described above, flexible allocation can be performed by controlling the allocation of UL data and DMRS while permitting demodulation using DMRS across subframes and / or slots. On the other hand, when only one transmission of the UL data and the DMRS overlaps with the UL transmission of another cell, there is a possibility that only one of the transmissions becomes power limited.

  Therefore, in the fourth aspect, the user terminal applies a predetermined modulation scheme to UL data (sPUSCH) and / or applies the same transmission power to UL data and DMRS. One transmission power (eg, the lower transmission power) is also applied to the other transmission. The application of the predetermined modulation scheme to the UL data and / or the application of the same transmission power to the UL data and the DMRS can use the method described in the second aspect.

(Wireless communication system)
Hereinafter, the configuration of the wireless communication system according to the present embodiment will be described. In this wireless communication system, the wireless communication methods according to the above aspects are applied. Note that the wireless communication methods according to the above aspects may be applied alone or in combination.

  FIG. 9 is a diagram illustrating an example of a schematic configuration of the wireless communication system according to the present embodiment. In the wireless communication system 1, carrier aggregation (CA) and / or dual connectivity (DC) in which a plurality of basic frequency blocks (component carriers) each having a unit of a system bandwidth (for example, 20 MHz) of an LTE system are applied. can do. The wireless communication system 1 may be referred to as SUPER 3G, LTE-A (LTE-Advanced), IMT-Advanced, 4G, 5G, FRA (Future Radio Access), NR (New Rat), or the like.

  The radio communication system 1 illustrated in FIG. 9 includes a radio base station 11 forming a macro cell C1, and radio base stations 12a to 12c arranged in the macro cell C1 and forming a small cell C2 smaller than the macro cell C1. . Further, user terminals 20 are arranged in the macro cell C1 and each small cell C2. A configuration in which different numerology (for example, different TTI length and / or processing time) is applied between cells may be adopted. The new melology refers to a signal design in a certain RAT and a set of communication parameters characterizing the RAT design.

  The user terminal 20 can be connected to both the radio base station 11 and the radio base station 12. It is assumed that the user terminal 20 simultaneously uses the macro cell C1 and the small cell C2 using different frequencies by CA or DC. Also, the user terminal 20 can apply CA or DC using a plurality of cells (CCs) (for example, two or more CCs). Also, the user terminal can use the licensed band CC and the unlicensed band CC as a plurality of cells. Note that a configuration may be employed in which an FDD carrier and / or a TDD carrier to which the shortened TTI is applied is included in any of a plurality of cells.

  Communication between the user terminal 20 and the radio base station 11 can be performed using a carrier having a relatively low frequency band (for example, 2 GHz) and a narrow bandwidth (called an existing carrier or a legacy carrier). On the other hand, between the user terminal 20 and the radio base station 12, a carrier having a relatively high frequency band (for example, 3.5 GHz, 5 GHz, 30 to 70 GHz, etc.) and a wide bandwidth may be used, The same carrier as that between base station 11 may be used. Note that the configuration of the frequency band used by each wireless base station is not limited to this.

  A wired connection (for example, an optical fiber compliant with CPRI (Common Public Radio Interface), an X2 interface, or the like) or a wireless connection between the wireless base station 11 and the wireless base station 12 (or between the two wireless base stations 12). Configuration.

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

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

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

  In the wireless communication system 1, OFDMA (orthogonal frequency division multiple access) can be applied to the downlink (DL) and SC-FDMA (single carrier-frequency division multiple access) can be applied to the uplink (UL) as a wireless access method. it can. OFDMA is a multicarrier transmission scheme in which a frequency band is divided into a plurality of narrow frequency bands (subcarriers), and data is mapped to each subcarrier to perform communication. SC-FDMA is a single-carrier transmission scheme that divides a system bandwidth into one or a band composed of continuous resource blocks for each terminal, and reduces interference between terminals by using different bands for a plurality of terminals. is there. The uplink and downlink radio access schemes are not limited to these combinations, and UL may use OFDMA.

  In the wireless communication system 1, as a DL channel, a DL data channel (also referred to as a PDSCH: Physical Downlink Shared Channel, a DL shared channel, etc.) shared by the user terminals 20, a broadcast channel (PBCH: Physical Broadcast Channel), L1 / L2 A control channel or the like is used. The PDSCH transmits user data, higher layer control information, SIB (System Information Block), and the like. An MIB (Master Information Block) is transmitted by the PBCH.

  The L1 / L2 control channel includes a DL control channel (PDCCH (Physical Downlink Control Channel), EPDCCH (Enhanced Physical Downlink Control Channel)), PCFICH (Physical Control Format Indicator Channel), PHICH (Physical Hybrid-ARQ Indicator Channel), and the like. . Downlink control information (DCI: Downlink Control Information) including scheduling information of PDSCH and PUSCH is transmitted by PDCCH. The number of OFDM symbols used for PDCCH is transmitted by PCFICH. HARQ transmission acknowledgment information (ACK / NACK) for PUSCH is transmitted by PHICH. The EPDCCH is frequency-division multiplexed with the PDSCH (Downlink Shared Data Channel), and is used for transmission of DCI and the like like the PDCCH.

  In the wireless communication system 1, as the UL channel, a UL data channel (also referred to as a PUSCH: Physical Uplink Shared Channel, a UL shared channel, etc.) shared by each user terminal 20, a UL control channel (PUCCH: Physical Uplink Control Channel), a random An access channel (PRACH: Physical Random Access Channel) or the like is used. User data and higher layer control information are transmitted by PUSCH. Uplink control information (UCI) including at least one of acknowledgment information (ACK / NACK) and radio quality information (CQI) is transmitted by PUSCH or PUCCH. The PRACH transmits a random access preamble for establishing a connection with a cell.

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

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

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

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

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

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

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

  Note that the transmission / reception unit 103 includes a DL signal (for example, a DL control signal (DL control channel), a DL data signal (DL data channel, DL shared channel), a DL reference signal (DM-RS, CSI-RS, etc.), a discovery signal , A synchronization signal, a broadcast signal, etc.) and receive an UL signal (eg, a UL control signal (UL control channel), a UL data signal (UL data channel, UL shared channel), a UL reference signal, etc.).

  Specifically, the transmitting / receiving section 103 receives the UL signal transmitted from the user terminal and the UL reference signal used for demodulating the UL signal using the same transmission time interval or different transmission time intervals. In addition, the transmitting / receiving section 103 notifies the user terminal of information on the allocation position (DMRS pattern) of the UL reference signal (DMRS) in the predetermined short TTI. In addition, the transmission / reception unit 103 may notify information on a modulation scheme applied to the UL signal (for example, sPUSCH) by the user terminal. The transmission unit and the reception unit of the present invention are configured by the transmission / reception unit 103 and / or the transmission path interface 106.

  FIG. 11 is a diagram illustrating an example of a functional configuration of the radio base station according to the present embodiment. Note that FIG. 11 mainly illustrates functional blocks of characteristic portions in the present embodiment, and it is assumed that the wireless base station 10 also has other functional blocks necessary for wireless communication. As shown in FIG. 11, the baseband signal processing unit 104 includes at least a control unit 301, a transmission signal generation unit 302, a mapping unit 303, a reception signal processing unit 304, and a measurement unit 305.

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

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

  The control unit 301 controls scheduling of DL signals and / or UL signals (for example, resource allocation). More specifically, the control unit 301 generates and transmits a DCI (DL assignment) including the scheduling information of the DL data channel and a DCI (UL grant) including the scheduling information of the UL data channel. 302, the mapping unit 303, and the transmission / reception unit 103.

  The control unit 301 controls the assignment of the UL signal so that only one of the transmission of the UL signal and the transmission of the UL reference signal corresponding to the UL signal does not overlap between a plurality of cells (first mode). Alternatively, the control unit 301 controls the assignment by allowing only one of the transmission of the UL signal and the transmission of the UL reference signal corresponding to the UL signal to be overlapped between a plurality of cells (second mode).

  Also, the control unit 301 does not allow demodulation using a UL reference signal that crosses subframes (corss-subframe DMRS demodulation) and / or demodulation using a UL reference signal that crosses slots (cross-slot DMRS demodulation). Is controlled (third mode). Alternatively, the control unit 301 controls the allocation by allowing demodulation using a UL reference signal that crosses subframes and / or demodulation using a UL reference signal that crosses slots (fourth aspect).

  The control unit 301 controls the UL signal and the UL reference signal for demodulating the UL signal so as to be arranged continuously or discontinuously. For example, the control unit 301 performs control such that the UL signal and the UL reference signal are arranged in the same sTTI or different sTTIs. Further, control section 301 may limit the modulation scheme applied to the UL signal (for example, sPUSCH) to transport shift keying (for example, QPSK) and notify the user terminal.

  Transmission signal generation section 302 generates a DL signal (DL control channel, DL data channel, DL reference signal such as DM-RS, etc.) based on an instruction from control section 301, and outputs it to mapping section 303. The transmission signal generation unit 302 can be configured from a signal generator, a signal generation circuit, or a signal generation device described based on common recognition in the technical field according to the present invention.

  Mapping section 303 maps the DL signal generated by transmission signal generation section 302 to a predetermined radio resource based on an instruction from control section 301, and outputs the result to transmission / reception section 103. The mapping unit 303 can be composed of a mapper, a mapping circuit, or a mapping device described based on common recognition in the technical field according to the present invention.

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

  The reception signal processing unit 304 outputs the information decoded by the reception processing to the control unit 301. For example, the reception processing unit 304 outputs at least one of a preamble, control information, and UL data to the control unit 301. Further, the reception signal processing unit 304 outputs the reception signal and the signal after the reception processing to the measurement unit 305.

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

  The measurement unit 305 may measure, for example, the reception power (for example, RSRP (Reference Signal Received Power)), the reception quality (for example, RSRQ (Reference Signal Received Quality)) of the received signal, the channel state, and the like. The measurement result may be output to the control unit 301.

<User terminal>
FIG. 12 is a diagram showing an example of the overall configuration of the user terminal according to the present embodiment. The user terminal 20 includes a plurality of transmitting / receiving antennas 201, an amplifier unit 202, a transmitting / receiving unit 203, a baseband signal processing unit 204, and an application unit 205. The transmitting / receiving antenna 201, the amplifier unit 202, and the transmitting / receiving unit 203 may be configured to include at least one each.

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

  The baseband signal processing unit 204 performs FFT processing, error correction decoding, reception processing for retransmission control, and the like on the input baseband signal. The DL data is transferred to the application unit 205. The application unit 205 performs processing related to a layer higher than the physical layer and the MAC layer. Further, of the DL data, system information and higher layer control information are also transferred to the application unit 205.

  On the other hand, UL data is input from the application unit 205 to the baseband signal processing unit 204. The baseband signal processing section 204 performs retransmission control transmission processing (eg, HARQ transmission processing), channel coding, precoding, discrete Fourier transform (DFT) processing, IFFT processing, and the like, and performs transmission and reception. The data is transferred to the unit 203. The transmission / reception unit 203 converts the baseband signal output from the baseband signal processing unit 204 into a radio frequency band and transmits the radio frequency band. The radio frequency signal frequency-converted by the transmission / reception unit 203 is amplified by the amplifier unit 202 and transmitted from the transmission / reception antenna 201.

  Note that the transmission / reception unit 203 includes a DL signal (for example, a DL control signal (DL control channel), a DL data signal (DL data channel, DL shared channel), a DL reference signal (DM-RS, CSI-RS, etc.), a discovery signal , A synchronization signal, a broadcast signal, etc.) and transmit an UL signal (eg, a UL control signal (UL control channel), a UL data signal (UL data channel, UL shared channel), a UL reference signal, etc.).

  Specifically, the transmission / reception unit 203 transmits the UL signal and the UL reference signal used for demodulating the UL signal using the same transmission time interval or different transmission time intervals. In addition, the transmission / reception unit 203 receives information on the allocation position (DMRS pattern) of the UL reference signal (DMRS) in a predetermined short TTI. Further, the transmission / reception unit 203 may receive information on a modulation scheme applied to a UL signal (for example, sPUSCH). In addition, the transmission / reception unit 203 performs transmission without permitting only one of the transmission of the UL signal and the transmission of the UL reference signal between a plurality of cells (first mode), or performs transmission while permitting it (first mode). Second aspect).

  FIG. 13 is a diagram illustrating an example of a functional configuration of the user terminal according to the present embodiment. Note that FIG. 13 mainly shows functional blocks of characteristic portions in the present embodiment, and it is assumed that the user terminal 20 also has other functional blocks necessary for wireless communication. As illustrated in FIG. 13, the baseband signal processing unit 204 of the user terminal 20 includes a control unit 401, a transmission signal generation unit 402, a mapping unit 403, a reception signal processing unit 404, and a measurement unit 405. I have at least.

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

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

  The control unit 401 controls the transmission of the UL signal so that only one of the transmission of the UL signal and the transmission of the UL reference signal corresponding to the UL signal does not overlap between a plurality of cells (first mode). Alternatively, the control unit 401 controls the transmission by allowing only one of the transmission of the UL signal and the transmission of the UL reference signal corresponding to the UL signal to overlap between a plurality of cells (second aspect).

  In addition, the control unit 401 does not allow demodulation using a UL reference signal across subframes (corss-subframe DMRS demodulation) and / or demodulation using a UL reference signal across slots (cross-slot DMRS demodulation). Is controlled (third mode). Alternatively, the control unit 401 controls transmission by permitting demodulation using a UL reference signal that crosses subframes and / or demodulation using a UL reference signal that crosses slots (fourth mode).

  The control unit 401 applies a predetermined modulation scheme to the UL signal and / or the same transmission power to the UL signal and the UL reference signal. Further, control section 401 applies transport shift keying to the UL signal, and applies different transmission power to the UL signal and the UL reference signal that are arranged discontinuously in the time direction in a predetermined cell. Further, when the transmission power exceeds a predetermined value when transmitting the UL signal and / or the UL reference signal, the control unit 401 applies power scaling independently to the UL signal and the UL reference signal (see FIGS. 4 and 5). ).

  Further, control section 401 may set the lower transmission power of the transmission power required for the UL signal and the transmission power required for the UL reference signal as the transmission power of the UL signal and the UL reference signal (FIG. 7). reference).

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

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

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

  The received signal processing unit 404 performs blind decoding on the DL control channel for scheduling transmission and / or reception of the DL data channel based on the instruction of the control unit 401, and performs reception processing of the DL data channel based on the DCI. Further, received signal processing section 404 estimates a channel gain based on DM-RS or CRS, and demodulates a DL data channel based on the estimated channel gain.

  The reception signal processing unit 404 outputs the information decoded by the reception processing to the control unit 401. The reception signal processing unit 404 outputs, for example, broadcast information, system information, RRC signaling, DCI, and the like to the control unit 401. The reception signal processing unit 404 may output the data decoding result to the control unit 401. Further, the reception signal processing unit 404 outputs the reception signal and the signal after the reception processing to the measurement unit 405.

  The measurement unit 405 performs measurement on the received signal. For example, the measurement unit 405 measures a channel state based on a channel state measurement reference signal (CSI-RS) transmitted from the radio base station. Further, measuring section 405 may measure the received power (eg, RSRP), DL reception quality (eg, RSRQ) of the received signal, and the like. The measurement result may be output to the control unit 401. The measurement unit 405 can be configured from a measurement device, a measurement circuit, or a measurement device described based on common recognition in the technical field according to the present invention.

<Hardware configuration>
Note that the block diagram used in the description of the above-described embodiment shows blocks in functional units. These functional blocks (components) are realized by an arbitrary combination of hardware and / or software. The means for implementing each functional block is not particularly limited. That is, each functional block may be realized by one device physically and / or logically coupled, or two or more devices physically and / or logically separated from each other directly and / or indirectly. (For example, wired and / or wireless), and may be realized by the plurality of devices.

  For example, a wireless base station, a user terminal, and the like according to an embodiment of the present invention may function as a computer that performs processing of the wireless communication method of the present invention. FIG. 14 is a diagram illustrating an example of a hardware configuration of a radio base station and a user terminal according to an embodiment of the present invention. The above-described wireless base station 10 and user terminal 20 may be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, and the like. Good.

  In the following description, the term “apparatus” can be read as a circuit, a device, a unit, or the like. The hardware configuration of the radio base station 10 and the user terminal 20 may be configured to include one or more of the devices illustrated in the drawing, or may be configured to exclude some of the devices.

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

  Each function of the radio base station 10 and the user terminal 20 is performed by, for example, reading predetermined software (program) on hardware such as the processor 1001 and the memory 1002 so that the processor 1001 performs an arithmetic operation and the communication by the communication device 1004. Alternatively, it is realized by controlling reading and / or writing of data in the memory 1002 and the storage 1003.

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

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

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

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

  The communication device 1004 is hardware (transmission / reception device) for performing communication between computers via a wired and / or wireless network, and is also referred to as, for example, a network device, a network controller, a network card, a communication module, or the like. The communication device 1004 includes, for example, a high-frequency switch, a duplexer, a filter, a frequency synthesizer, and the like in order to realize, for example, frequency division duplex (FDD) and / or time division duplex (TDD). It may be configured. For example, the transmission / reception antenna 101 (201), the amplifier unit 102 (202), the transmission / reception unit 103 (203), the transmission line interface 106, and the like described above may be realized by the communication device 1004.

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

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

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

(Modification)
Note that terms described in this specification and / or terms necessary for understanding this specification may be replaced with terms having the same or similar meanings. For example, channels and / or symbols may be signaling. Also, the signal may be a message. The reference signal may be abbreviated as RS (Reference Signal), and may be referred to as a pilot, a pilot signal, or the like according to an applied standard. Further, a component carrier (CC) may be called a cell, a frequency carrier, a carrier frequency, or the like.

  Further, the radio frame may be configured with one or a plurality of periods (frames) in the time domain. The one or more respective periods (frames) forming the radio frame may be referred to as a subframe. Furthermore, a subframe may be configured with one or more slots in the time domain. Furthermore, a slot may be configured with one or more symbols (such as OFDM (Orthogonal Frequency Division Multiplexing) symbols and SC-FDMA (Single Carrier Frequency Division Multiple Access) symbols) in the time domain.

  Each of the radio frame, the subframe, the slot, and the symbol represents a time unit when transmitting a signal. The radio frame, the subframe, the slot, and the symbol may use different names corresponding to each. For example, one subframe may be called a transmission time interval (TTI), a plurality of consecutive subframes may be called a TTI, and one slot may be called a TTI. That is, the subframe or TTI may be a subframe (1 ms) in the existing LTE, a period shorter than 1 ms (for example, 1 to 13 symbols), or a period longer than 1 ms. Is also good.

  Here, the TTI refers to, for example, a minimum time unit of scheduling in wireless communication. For example, in the LTE system, a radio base station performs scheduling for allocating radio resources (such as a frequency bandwidth and transmission power that can be used in each user terminal) to each user terminal in TTI units. Note that the definition of TTI is not limited to this. The TTI may be a unit of transmission time of a channel-encoded data packet (transport block) or a unit of processing such as scheduling and link adaptation.

  A TTI having a time length of 1 ms may be referred to as a normal TTI (TTI in LTE Rel. 8-12), a normal TTI, a long TTI, a normal subframe, a normal subframe, a long subframe, or the like. A TTI shorter than the normal TTI may be called a shortened TTI, a short TTI, a shortened subframe, a short subframe, or the like.

  A resource block (RB) is a resource allocation unit in the time domain and the frequency domain, and may include one or a plurality of continuous subcarriers (subcarriers) in the frequency domain. Further, the RB may include one or a plurality of symbols in the time domain, and may have a length of one slot, one subframe, or one TTI. One TTI and one subframe may each be configured with one or a plurality of resource blocks. The RB may be called a physical resource block (PRB: Physical RB), a PRB pair, an RB pair, or the like.

  Further, the resource block may be composed of one or more resource elements (REs). For example, one RE may be a radio resource area of one subcarrier and one symbol.

  Note that the above-described structures of the radio frame, the subframe, the slot, and the symbol are merely examples. For example, the number of subframes included in a radio frame, the number of slots included in a subframe, the number of symbols and RBs included in slots, the number of subcarriers included in RBs, the number of symbols in a TTI, the symbol length, A configuration such as a cyclic prefix (CP) length can be variously changed.

  In addition, the information, parameters, and the like described in this specification may be represented by an absolute value, may be represented by a relative value from a predetermined value, or may be represented by another corresponding information. . For example, the radio resource may be indicated by a predetermined index. Further, the formulas and the like that use these parameters may differ from those explicitly disclosed herein.

  The names used for parameters and the like in this specification are not limiting in any way. For example, various channels (PUCCHs (Physical Uplink Control Channels), PDCCHs (Physical Downlink Control Channels), etc.) and information elements can be identified by any suitable name, so that various channels assigned to these various channels and information elements can be identified. The nomenclature is not limiting in any way.

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

  In addition, information, signals, and the like can be output from an upper layer to a lower layer and / or from a lower layer to an upper layer. Information, signals, etc. may be input / output via a plurality of network nodes.

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

  The notification of information is not limited to the aspects / embodiments described herein, and may be performed in other ways. For example, the notification of information includes physical layer signaling (eg, downlink control information (DCI: Downlink Control Information), uplink control information (UCI: Uplink Control Information)), higher layer signaling (eg, RRC (Radio Resource Control) signaling, Broadcast information (Master Information Block (MIB), System Information Block (SIB), etc.), MAC (Medium Access Control) signaling), other signals, or a combination thereof may be used.

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

  In addition, the notification of the predetermined information (for example, the notification of “X”) is not limited to explicitly performed, and is implicitly performed (for example, by not performing the notification of the predetermined information or by another (By notification of information).

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

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

  In addition, software, instructions, information, and the like may be transmitted and received via a transmission medium. For example, if the software uses wired technology (coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), etc.) and / or wireless technology (infrared, microwave, etc.), the website, server, etc. , Or when transmitted from another remote source, these wired and / or wireless technologies are included within the definition of the transmission medium.

  The terms "system" and "network" as used herein are used interchangeably.

  As used herein, the terms “base station (BS),” “wireless base station,” “eNB,” “cell,” “sector,” “cell group,” “carrier,” and “component carrier” , Can be used interchangeably. A base station may also be referred to as a fixed station, a NodeB, an eNodeB (eNB), an access point, an access point, a transmission point, a reception point, a femtocell, a small cell, and the like.

  A base station can accommodate one or more (eg, three) cells (also referred to as sectors). If the base station accommodates multiple cells, the entire coverage area of the base station can be partitioned into multiple smaller areas, each smaller area being a base station subsystem (eg, a small indoor base station (RRH: The term “cell” or “sector” may refer to a part or the whole of the coverage area of a base station and / or a base station subsystem serving a communication service in this coverage. Point.

  As used herein, the terms “Mobile Station (MS)”, “User Terminal”, “User Equipment (UE)” and “Terminal” may be used interchangeably. A base station may also be referred to as a fixed station, a NodeB, an eNodeB (eNB), an access point, an access point, a transmission point, a reception point, a femtocell, a small cell, and the like.

  A mobile station can be a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, by one of ordinary skill in the art. It may also be called a terminal, a remote terminal, a handset, a user agent, a mobile client, a client or some other suitable term.

  Further, the wireless base station in this specification may be replaced with a user terminal. For example, each aspect / embodiment of the present invention may be applied to a configuration in which communication between a wireless base station and a user terminal is replaced with communication between a plurality of user terminals (D2D: Device-to-Device). In this case, the configuration may be such that the user terminal 20 has the function of the wireless base station 10 described above. Further, words such as “up” and “down” may be read as “side”. For example, an uplink channel may be read as a side channel.

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

  In this specification, a specific operation performed by a base station may be performed by an upper node thereof in some cases. In a network consisting of one or more network nodes having base stations, various operations performed for communication with terminals can be performed by a base station, one or more network nodes other than base stations (eg, Obviously, it can be performed by an MME (Mobility Management Entity), an S-GW (Serving-Gateway) or the like, but not limited thereto, or a combination thereof.

  Each aspect / embodiment described in this specification may be used alone, may be used in combination, or may be switched as the execution goes on. In addition, the processing procedure, sequence, flowchart, and the like of each aspect / embodiment described in this specification may be interchanged as long as there is no inconsistency. For example, the methods described herein present elements of various steps in a sample order, and are not limited to the specific order presented.

  Each of the aspects / embodiments described in this specification is based on Long Term Evolution (LTE), LTE-A (LTE-Advanced), LTE-B (LTE-Beyond), SUPER 3G, IMT-Advanced, 4G (4th generation mobile). communication system), 5G (5th generation mobile communication system), FRA (Future Radio Access), New-RAT (Radio Access Technology), NR (New Radio), NX (New radio access), FX (Future generation radio access), GSM (Global System for Mobile communications), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802 .20, UWB (Ultra-WideBand), Bluetooth (registered trademark), and other appropriate wireless communication methods The present invention may be applied to a system using the method and / or a next-generation system extended based on the method.

  The phrase "based on" as used herein does not mean "based solely on" unless stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

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

  The term "determining" as used herein may encompass a wide variety of actions. For example, “determining” can include calculating, computing, processing, deriving, investigating, looking up (eg, a table, database, or other data). It may be regarded as "determining" such as searching in a structure), ascertaining, and the like. Also, “determining” includes receiving (eg, receiving information), transmitting (eg, transmitting information), input (input), output (output), and access ( accessing) (e.g., accessing data in a memory) or the like. Also, “judgment (decision)” is regarded as “judgment (decision)” of resolving, selecting, selecting, establishing, comparing, etc. Is also good. That is, “judgment (decision)” may be regarded as “judgment (decision)” of any operation.

  As used herein, the terms "connected," "coupled," or any variation thereof, refer to any direct or indirect connection or indirect connection between two or more elements. Coupling is meant and may include the presence of one or more intermediate elements between two elements "connected" or "coupled" to each other. The coupling or connection between the elements may be physical, logical, or a combination thereof. As used herein, two elements are defined by the use of one or more electrical wires, cables and / or printed electrical connections, and, as some non-limiting and non-exhaustive examples, radio frequency By using electromagnetic energy, such as electromagnetic energy having wavelengths in the region, microwave region and light (both visible and invisible) region, it can be considered to be "connected" or "coupled" to each other.

  Where the terms “including”, “comprising”, and variations thereof, are used in the present description or claims, these terms are inclusive, as are the terms “comprising” It is intended to be Further, it is intended that the term "or", as used herein or in the claims, not be the exclusive OR.

  Although the present invention has been described in detail, it will be apparent to those skilled in the art that the present invention is not limited to the embodiments described in this specification. The present invention can be embodied as modified and changed aspects without departing from the spirit and scope of the present invention defined by the description of the claims. Therefore, the description in this specification is for the purpose of illustrative explanation, and has no restrictive meaning to the present invention.

Claims (6)

In a plurality of cells, a transmission unit that transmits a UL signal and a UL reference signal used for demodulation of the UL signal using the same transmission time interval or different transmission time intervals,
A control unit that controls generation of the UL signal and the UL reference signal and / or transmission power,
The user terminal, wherein the control unit applies a predetermined modulation scheme to the UL signal and / or the same transmission power to the UL signal and the UL reference signal.   The user terminal according to claim 1, wherein the transmission unit performs transmission while allowing only one of the transmission of the UL signal and the transmission of the UL reference signal to overlap between the plurality of cells.   The control unit applies a transport shift keying to the UL signal, and applies different transmission power to the UL signal and the UL reference signal arranged discontinuously in a time direction in a predetermined cell. The user terminal according to claim 1 or 2.   The controller may apply power scaling independently to the UL signal and the UL reference signal when transmission power exceeds a predetermined value when transmitting the UL signal and / or the UL reference signal. The user terminal according to claim 1.   The control unit sets a lower transmission power among transmission power required for the UL signal and transmission power required for the UL reference signal, as transmission power of the UL signal and the UL reference signal. The user terminal according to claim 1, wherein A wireless communication method for a user terminal,
In a plurality of cells, transmitting a UL signal and a UL reference signal used for demodulation of the UL signal using the same transmission time interval or different transmission time intervals,
Controlling the generation and / or transmission power of the UL signal and the UL reference signal,
A wireless communication method, wherein a predetermined modulation scheme is applied to the UL signal and / or the same transmission power is applied to the UL signal and the UL reference signal.

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