KR20190031125A - Method for controlling transmit power of DMRS in new radio and Apparatuses thereof - Google Patents

Abstract

The present embodiments relate to a method for controlling the transmission power of a demodulation reference signal (DMRS) in a next generation/5G wireless access network. According to an embodiment of the present invention, the method is to transmit a DMRS to a terminal via a base station, comprising the steps of: determining a ratio of a DMRS resource element to a blank resource element within a DMRS symbol; determining a DMRS power increase amount based on the ratio value of the DMRS resource element to the blank resource element as described above; and transmitting the DMRS to the terminal with the power determined based on the DMRS power increase amount as described above.

Description

[0001] The present invention relates to a method and apparatus for controlling transmission power of a DMRS in a next-generation wireless network,

The present embodiments describe a method of controlling the transmission power of the DMRS in the next generation / 5G radio access network (hereinafter referred to as NR (New Radio) in the present invention).

3GPP recently approved a study item "Study on New Radio Access Technology" for studying next generation / 5G radio access technology, and based on this, RAN WG1 provides frame structure, channel coding and modulation for NR (New Radio) , Waveforms and multiple access methods. NR is required not only to improve data transmission rate in comparison with LTE / LTE-Advanced, but also to design various requirements that are required according to detailed and specific usage scenarios.

In order to meet the requirements of each scenario, LTE / LTE-Advanced has been proposed as a representative use scenario of NR. In this case, enhancement Mobile BroadBand (MMB), massive Machine Type Communication (MMTC) and Ultra Reliable and Low Latency Communications A flexible frame structure design is required.

In particular, when a base station transmits a DMRS to a mobile station in the NR, it is necessary to determine a specific method for increasing the transmission power of the DMRS considering a DMRS resource element (RE) and a data resource element multiplexed on the DMRS symbol It is being raised.

It is an object of the present embodiments to provide a concrete method of increasing a transmission power of a DMRS when a base station transmits a DMRS to a terminal in a next generation / 5G radio access network.

According to an embodiment of the present invention, there is provided a method of transmitting a Demodulation Reference Signal (DMRS) to a mobile station, the method comprising: determining a ratio of a blank resource element to a DMRS resource element in a DMRS symbol; Determining a DMRS power increase based on a ratio value of a blank resource element to a DMRS resource element, and transmitting the DMRS to the terminal using the determined power based on the DMRS power increase amount. to provide.

According to an embodiment of the present invention, there is provided a method of receiving a Demodulation Reference Signal (DMRS) from a base station, the method comprising: receiving information on a ratio of a blank resource element to a DMRS resource element in a DMRS symbol; And receiving from the base station a power-increased DMRS according to a DMRS power increase determined based on a ratio value of the contrast blank resource element.

In an exemplary embodiment of the present invention, a base station for transmitting a Demodulation Reference Signal (DMRS) to a mobile station determines a ratio of a blank resource element to a DMRS resource element in a DMRS symbol, And a transmitter for transmitting the DMRS to the mobile station based on the power determined based on the DMRS power increase amount.

In an exemplary embodiment of the present invention, a terminal that receives a Demodulation Reference Signal (DMRS) from a base station receives information on a ratio of a blank resource element to a DMRS resource element in a DMRS symbol, And a receiver for receiving from the base station a DMRS whose power is increased according to the increase amount of the DMRS power determined based on the ratio value of the elements.

According to the present embodiments, when a base station transmits a DMRS to a terminal in a next generation / 5G radio access network, a concrete method of increasing the transmission power of the DMRS can be provided.

FIG. 1 illustrates the alignment of OFDM symbols in the case of using different subcarrier spacings according to the present embodiments. Referring to FIG.
2 is a diagram illustrating a downlink (DL) DMRS structure in LTE-A.
FIG. 3 is a diagram illustrating a 1-symbol DMRS structure configured by a Comb2 + CS scheme.
FIG. 4 is a diagram illustrating a 2-symbol DMRS structure configured by the Comb2 + CS scheme.
FIG. 5 is a diagram illustrating a 1-symbol DMRS structure configured by a 2-FD-OCC scheme.
FIG. 6 is a diagram illustrating a 2-symbol DMRS structure configured by a 2-FD-OCC scheme.
7 is a diagram illustrating an example of increasing the transmission power of the DMRS using rate matching information between the PDSCH and the DMRS in the first DMRS setting type.
8 is a diagram illustrating an example of increasing the transmission power of the DMRS using rate matching information between the PDSCH and the DMRS in the second DMRS setting type.
9 is a diagram illustrating an example of increasing the transmission power of the DMRS using rate matching information between the PDSCH and the DMRS and density information of the DMRS in the first DMRS setting type.
10 is a diagram illustrating an example of increasing the transmission power of the DMRS using rate matching information between the PDSCH and the DMRS and the density information of the DMRS in the second DMRS setting type.
11 is a diagram illustrating a specific procedure by which a base station transmits a DMRS to a mobile station in this embodiment.
FIG. 12 is a diagram illustrating a specific procedure in which a terminal receives a DMRS from a base station in this embodiment.
FIG. 13 is a diagram illustrating a configuration of a base station according to the present embodiments.
FIG. 14 is a diagram illustrating a configuration of a terminal according to the present embodiments.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. It should be noted that, in adding reference numerals to the constituent elements of the drawings, the same constituent elements are denoted by the same reference symbols as possible even if they are shown in different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

As used herein, a wireless communication system refers to a system for providing various communication services such as voice, packet data, and the like. A wireless communication system includes a user equipment (UE) and a base station (BS).

The user terminal is a comprehensive concept that means a terminal in a wireless communication, and it is a comprehensive concept which means a mobile station (MS) in GSM, a mobile station (MS) in UT (User Terminal), a Subscriber Station (SS), a wireless device, and the like.

A base station or a cell generally refers to a station that communicates with a user terminal and includes a Node-B, an evolved Node-B, a gNode-B, a Low Power Node A sector, a site, various types of antennas, a base transceiver system (BTS), an access point, a point (for example, a transmission point, a reception point, a transmission / reception point) (RRH), a radio unit (RU), and a small cell, as well as a relay cell, a relay node, a megacell, a macrocell, a microcell, a picocell, a femtocell, an RRH,

Since the various cells listed above exist in the base station controlling each cell, the base station can be interpreted into two meanings. Macro cell, micro cell, picocell, femtocell, small cell, or 2) the wireless region itself in connection with the wireless region. 1), all of the devices that interact to configure the wireless area to be cooperatively controlled by the same entity are all pointed to the base station. A point, a transmission / reception point, a transmission point, a reception point, and the like are examples of the base station according to the configuration method of the radio area. 2 may direct the base station to the wireless region itself to receive or transmit signals at the point of view of the user terminal or in the vicinity of the neighboring base station.

In this specification, a cell refers to a component carrier having a coverage of a signal transmitted from a transmission point or a transmission point or a transmission point or a transmission / reception point of a signal transmitted from a transmission / reception point, and a transmission / reception point itself .

Herein, the user terminal and the base station are used in a broad sense as two (uplink or downlink) transmitting and receiving subjects used to implement the technology or technical idea described in the present invention, and are not limited by a specific term or word Do not.

Here, an uplink (UL, or uplink) means a method of transmitting / receiving data to / from a base station by a user terminal, and a downlink (DL or downlink) .

The time division duplex (TDD) scheme, which is transmitted using different time periods, can be used for the uplink and downlink transmission, and a frequency division duplex (FDD) scheme in which different frequencies are used, a TDD scheme and an FDD scheme A hybrid method can be used.

In the wireless communication system, the uplink and the downlink are configured with reference to one carrier or carrier pair to form a standard.

The uplink and the downlink transmit control information through a control channel such as a physical downlink control channel (PDCCH), a physical uplink control channel (PUCCH), and the like. The physical downlink shared channel (PDSCH), the physical uplink shared channel (PUSCH) It is composed of the same data channel and transmits data.

A downlink may refer to a communication or communication path from a multipoint transmission / reception point to a terminal, and an uplink may refer to a communication or communication path from a terminal to a multiple transmission / reception point. At this time, in the downlink, the transmitter may be a part of the multiple transmission / reception points, and the receiver may be a part of the terminal. Also, in the uplink, the transmitter may be a part of the terminal, and the receiver may be a part of multiple transmission / reception points.

Hereinafter, a situation in which a signal is transmitted / received through a channel such as PUCCH, PUSCH, PDCCH, and PDSCH is expressed as 'PUCCH, PUSCH, PDCCH and PDSCH are transmitted and received'.

Meanwhile, the High Layer Signaling described below includes RRC signaling for transmitting RRC information including RRC parameters.

The base station performs downlink transmission to the UEs. The base station includes downlink control information, such as scheduling, required for reception of a downlink data channel, which is a primary physical channel for unicast transmission, and physical downlink control information for transmitting scheduling grant information for transmission in an uplink data channel. A control channel can be transmitted. Hereinafter, the transmission / reception of a signal through each channel will be described in a form in which the corresponding channel is transmitted / received.

There are no restrictions on multiple access schemes applied in wireless communication systems. (TDMA), Frequency Division Multiple Access (FDMA), Code Division Multiple Access (CDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Non-Orthogonal Multiple Access (NOMA) Various multiple access schemes such as OFDM-CDMA can be used. Here, the NOMA includes Sparse Code Multiple Access (SCMA) and Low Density Spreading (LDS).

One embodiment of the present invention relates to asynchronous wireless communications that evolve into LTE / LTE-Advanced, IMT-2020 over GSM, WCDMA, HSPA, and synchronous wireless communications such as CDMA, CDMA- Can be applied.

In this specification, a MTC (Machine Type Communication) terminal may mean a terminal supporting low cost (or low complexity) or a terminal supporting coverage enhancement. Alternatively, the MTC terminal may refer to a terminal defined in a specific category for supporting low cost (or low complexity) and / or coverage enhancement.

In other words, the MTC terminal in this specification may mean a newly defined 3GPP Release-13 low cost (or low complexity) UE category / type for performing LTE-based MTC-related operations. Alternatively, the MTC terminal may support enhanced coverage over the existing LTE coverage or a UE category / type defined in the existing 3GPP Release-12 or lower that supports low power consumption, or a newly defined Release-13 low cost low complexity UE category / type. Or a further Enhanced MTC terminal defined in Release-14.

In this specification, NarrowBand Internet of Things (NB-IoT) terminal means a terminal supporting wireless access for cellular IoT. The objectives of NB-IoT technology include improved indoor coverage, support for large-scale low-rate terminals, low latency sensitivity, ultra-low cost, low power consumption, and optimized network architecture.

Enhanced Mobile Broadband (eMBB), massive Machine Type Communication (mMTC), and Ultra Reliable and Low Latency Communication (URLLC) have been proposed as typical usage scenarios in NR (New Radio), which is under discussion in 3GPP.

In this specification, a frequency, a frame, a subframe, a resource, a resource block, a region, a band, a subband, a control channel, a data channel, a synchronization signal, various reference signals, various signals, May be interpreted as past or presently used meanings or various meanings used in the future.

[5G NR ]

Enhanced Mobile Broadband (eMBB), massive Machine Type Communication (mMTC), and Ultra Reliable and Low Latency Communication (URLLC) have been proposed as typical usage scenarios in NR (New Radio), which is under discussion in 3GPP.

In this specification, a frequency, a frame, a subframe, a resource, a resource block, a region, a band, a subband, a control channel, a data channel, a synchronization signal, various reference signals, various signals, May be interpreted as past or presently used meanings or various meanings used in the future.

3GPP recently approved a study item "Study on New Radio Access Technology" for studying next generation / 5G radio access technology. Based on this, 3GPP has developed frame structure, channel coding and modulation, waveform, The discussion on frame structure, channel coding & modulation, waveform & multiple access scheme, etc. has begun.

NR is required to be designed to satisfy not only the improved data transmission rate as compared to LTE / LTE-Advanced, but also various requirements that are required according to granular and specific usage scenarios. In particular, enhancement Mobile BroadBand (eMBB), massive MTC (MMTC) and Ultra Reliable and Low Latency Communications (URLLC) have been proposed as typical usage scenarios of NR, and requirements for each usage scenario have been proposed. It is required to design a flexible frame structure as compared with LTE / LTE-Advanced.

Since each usage scenario has different requirements for data rates, latency, coverage, etc., it is possible to use each frequency band constituting any NR system A radio resource unit based on different numerology (e.g., subcarrier spacing, subframe, TTI, etc.) is efficiently multiplexed as a method for efficiently satisfying requirements according to usage scenarios there is a need for a multiplexing method.

As a method for this, a numerator with different subcarrier spacing (SCS) values is multiplexed on a TDM, FDM or TDM / FDM basis via one NR carrier to support Methods and methods for supporting one or more time units in constructing scheduling units in the time domain have been discussed. In this regard, in the NR, a subframe has been defined as one type of time domain structure, and a reference numerology for defining a corresponding subframe duration has been described. We decided to define a single subframe duration consisting of 14 OFDM symbols of 15 kHz sub-carrier spacing (SCS) based normal CP overhead as LTE. Accordingly, the subframe in the NR has a time duration of 1 ms.

However, unlike LTE, the subframe of the NR is an absolute reference duration, which is the time unit on which the actual uplink data scheduling is based, as a slot and a mini-slot ) Can be defined. In this case, the number of OFDM symbols constituting the corresponding slot and the y-value are determined to have a value of y = 14 irrespective of the numerator.

Accordingly, an arbitrary slot may be composed of 14 symbols, and all symbols may be used for DL transmission according to a transmission direction of the slot, or all symbols may be used for uplink transmission UL transmission, or in the form of a DL portion + a gap + an UL portion.

Also, a minislot consisting of fewer symbols than a corresponding slot is defined in an arbitrary numerology (or SCS), and based on this, a time-domain scheduling interval with a short length for transmitting / receiving data upstream / scheduling interval may be set or a long-time time-domain scheduling interval for uplink / downlink data transmission / reception through slot aggregation may be configured.

In particular, for transmission and reception of latency-critical data such as URLLC, a slot of 0.5 ms (7 symbols) or 1 ms (14 symbols) defined in a transmitter-based frame structure having a small SCS value such as 15 kHz It is difficult to satisfy the latency requirement. Therefore, a mini-slot composed of a smaller number of OFDM symbols than the corresponding slot is defined, and a corresponding URLLC And scheduling for latency critical data such as < RTI ID = 0.0 > a < / RTI >

Alternatively, as described above, multiplexers supporting different SCS values in one NR carrier are multiplexed and supported by the TDM scheme or the FDM scheme, so that the number of slots (or mini- Scheduling of data in accordance with latency requirements is also considered. For example, as shown in FIG. 1, when the SCS is 60 kHz, the symbol length is reduced to about 1/4 of that of the SCS 15 kHz. Therefore, when one slot is composed of 7 OFDM symbols, While the slot length based on 60 kHz is reduced to about 0.125 ms.

As such, NR is discussing how to satisfy the requirements of URLLC and eMBB by defining different SCSs or different TTI lengths.

[ NR DMRS ]

In order to support 8-layer transmission, the existing DMRS (DL DMRS) of the existing LTE-A has a total of 8 antenna ports defined from ports 7 to 14. Thus, , And may be referred to as a DMRS port.)

2 shows a DMRS structure in which an orthogonal cover code (OCC) is applied for PDSCH transmission in an LTE downlink. Referring to FIG. 2, the antenna ports 7, 8, 11, and 13 use a DMRS resource element (RE) indicated by a pattern 1 in FIG. 2, and antenna ports 9, 10, 12, The indicated DMRS RE can be used.

In this case, an orthogonal cover code (OCC) is used to maintain the orthogonality between the antenna ports assigned to the same DMRS REs. The values are shown in Table 1 below.

The definition of NRRS downlink DMRS is as follows.

The terminal may be set to one of the front-loaded DMRS setting type 1 or the front-loaded DMRS setting type 2 via the upper layer for the DMRS pattern. front-loaded DMRS Configuration type 1 or from the front-loaded DMRS Configuration type 2 for DL / UL):

● Configuration type 1:

- One symbol:

  Com 2 + 2 CS, up to 4 ports (Comb 2 + 2 CS, up to 4 ports)

- Two symbols:

  CS + TD-OCC ({1 1} and {1 -1}), up to 8 ports (Comb 2 + 2 CS + 8 ports)

  It should be able to schedule up to 4 ports without using both {1,1} and {1, -1} (Note: It should be possible to schedule up to 4 ports without using both {1,1} and { 1, -1}.

● Configuration type 2:

- One symbol:

 (2-FD-OCC) adjacent adjacent REs in the frequency domain of up to 6 ports.

- Two symbols:

 2-FD-OCC + TD-OCC ({1,1} and {1, -1}) (2-FD-OCC adjacent adjacent REs in the frequency domain + TD- OCC (both {1,1} and {1, -1}) up to 12 ports)

It should be able to schedule up to 6 ports without using both {1,1} and {1, -1} (Note: It should be possible to schedule up to 6 ports without using both {1,1} and { 1, -1}.

From the point of view of the terminal, the CDM DMRS ports in the frequency domain can be quasi-colocated (from the UE perspective, frequency domain CDMed DMRS ports are QCLed).

● FFS: Whether the front-loaded DMRS setup type in the uplink and the downlink in the UE are different (FFS: Whether the front-load DMRS configuration type for a UE for UL and DL can be different or not.)

If there is a significant complexity / performance issue in the above discussion, a down-selection may be discussed (Note: If there are significant complexity / performance issues involved in the above agreements,

For NR DMRS, two types of DMRS can be supported. The type of DMRS used can be determined through configuration according to the maximum number of DMRS ports.

● Front-loaded DMRS configuration 1: Comb + CS structure + TD-OCC

● Front-loaded DMRS configuration 2: FD-OCC + TDM / TD-OCC

Hereinafter, the front-loaded DMRS setting 1 described above may be referred to as a first DMRS setting type, and the front-loaded DMRS setting 2 may be referred to as a second DMRS setting type.

Comb + Cycle shift (Comb + CS) based DMRS structure (Up to 8 DMRS  Port support)

In the above-mentioned front-loaded DMRS setting 1, two structures can be defined according to the number of symbols to which the DMRS is transmitted. This can be divided into a 1-symbol DMRS structure as shown in FIG. 3 and a 2-symbol DMRS structure as shown in FIG.

The 1-symbol DMRS means a DMRS composed of one symbol, and the 2-symbol DMRS means a DMRS composed of 2 symbols. Thus, a particular DMRS may be located in one or two symbol intervals on a resource block.

For example, in FIG. 3, a DMRS may be located on a symbol indicated by a symbol index 2, and a symbol indicated by a symbol index 2 may be a DMRS symbol, that is, a symbol to which a DMRS can be allocated on a resource block .

In another example, in FIG. 4, a DMRS may be located on a symbol indicated by symbol index 2 or 3. In this case, a symbol indicated by symbol index 2 or 3 may be a DMRS symbol, .

A resource block (RB) is a unit used for scheduling a data channel or a control channel with a terminal in a base station, and is configured in the form of a two-dimensional block on the frequency axis and the time axis. Each resource block may be composed of a plurality of resource elements (REs), and each resource element may be indicated by a specific symbol index and a subcarrier index. Hereinafter, a case where one resource block is composed of 14 OFDM symbols on the time axis and 12 subcarriers are arranged on the frequency axis will be described as an example.

In this case, a comb refers to a method in which a DMRS is mapped on a resource block, which means that a DMRS set to the same DMRS port is mapped to a subcarrier having a predetermined interval. For example, Comb2 is set so that the difference between subcarriers indexes between DMRSs set to the same DMRS port is 2 (for example, the DMRS set to DMRS port 0 is located at subcarrier index 0,2,4,6,8,10 Comb4 means that the difference of the subcarrier index set to the same DMRS port is set to 4 (DMRS set to eg DMRS port 0 is located at subcarrier index 0,4,8).

FIG. 3 is a diagram illustrating a 1-symbol DMRS structure configured by a Comb2 + CS scheme.

First, as shown in FIG. 3, a Comb 2 + 2 CS structure will be described. In total, two areas may exist for each subcarrier. Here, the area indicated by the pattern of (1) and the area indicated by the pattern of (2) are distinguished, and two cyclic shift values are applied to each area, so that a total of four orthogonal ports can be generated.

FIG. 4 is a diagram illustrating a 2-symbol DMRS structure configured by the Comb2 + CS scheme.

Referring to FIG. 4, a 2-symbol DMRS structure is shown in FIG. 4, and a basic structure can use a pattern that repeats the case of a 1-symbol DMRS structure. However, the difference from the 1-symbol DMRS structure is how to spread by applying the method in the time domain.

For example, in the case of TD-OCC = {(1,1)}, the number of supported DMRS ports does not increase as a simple repetition structure. However, since TD-OCC = {(1,1), (1, -1)} uses two orthogonal codes, the maximum number of DMRS ports that can be supported can be doubled.

FD - OCC  Pattern-based DMRS structure (Up to 12 DMRS  Port support)

In the above-described front-loaded DMRS setting 2, two modes can be defined according to the number of symbols to which the DMRS is transmitted. This can be divided into a 1-symbol DMRS as shown in FIG. 5 and a 2-symbol DMRS structure as shown in FIG.

FIG. 5 is a diagram illustrating a 1-symbol DMRS structure configured by a 2-FD-OCC scheme.

First, as shown in FIG. 5, a 2-FD-OCC up to 6 ports (2-FD-OCC) structure having a maximum of 6 ports is first described. Two consecutive subcarriers in the frequency domain are allocated to one DMRS . That is, as shown in FIG. 3 and FIG. 4, the DMRS may be located in two subcarrier intervals instead of being located in one subcarrier interval.

In this case, 2-FD-OCC basically uses OCC (= {(1,1), (1, -1)} of length-2) It can support two DMRS ports. Therefore, in FIG. 5, there are three areas denoted by the patterns of (1), (2) and (3) in total, so that a total of six DMRS ports can be supported.

FIG. 6 is a diagram illustrating a 2-symbol DMRS structure configured by a 2-FD-OCC scheme.

FIG. 6 shows a 2-symbol DMRS structure. The basic structure is based on a 1-symbol DMRS pattern, but TD-OCC is applied to support a maximum of 12 ports.

For example, since two orthogonal codes are additionally used in TD-OCC = {(1,1), (1, -1)}, 6 symbols = 6 * 2 = 12 symbols Port can be supported.

Hereinafter, various embodiments of a method for controlling the transmission power of the DMRS when the base station transmits the DMRS to the mobile station based on the two types of DMRS setting types will be described in detail.

In the NR DMRS structure, unlike LTE, if all of the REs in the DMRS symbol are not assigned all of the DMRS ports, that is, if all DMRS ports are not allocated to all REs present on the symbol in which the DMRS exists, The remaining resource elements (REs) are empty REs.

There may be two options in which no data is allocated for such blank resource elements, or data is assigned through specific signaling.

If data is allocated to the blank resource element, as an example, data may be transmitted from the base station to the terminal via the downlink data channel (PDSCH). Therefore, the multiplexing and rate matching between the DMRS and the PDSCH, which will be described below, is an example of multiplexing and rate matching between the DMRS and the data.

In the present embodiments, a method of controlling the transmission power of the DMRS considering the rate matching between the NRDMRS symbols will be described. In this embodiment, since the method of increasing the transmission power of the DMRS mainly is disclosed, the method of controlling the transmission power of the DMRS can also be referred to as a power-boosting method of the DMRS.

Embodiments described below may be applied to both front-loaded DMRS symbol regions and additional DMRS symbol regions.

The embodiments described below may be applied individually or in any combination.

Example  One. DMRS  Power- Boosting (power-boosting) The setting value is  RRC Signaling  Or MAC Signaling  To the terminal and performs on / off through dynamic signaling, which is explicit or implicit.

In order to multiplex between the DMRS and the data on the DMRS symbol, information related to the setting of the DMRS port must be signaled to the UE. The specific signaling method currently under consideration is as follows.

 ● Signaling the maximum number of DMRS ports to the terminal

 ● Signaling to the terminal the number of DMRS patterns assigned / unassigned to the terminal

 ● Signaling to the terminal the number of DMRS groups assigned / unassigned to the terminal

However, the present embodiment can be applied equally to the case in which the information on the multiplexing between the DMRS and data for the UE is determined by any one of the above-mentioned signaling methods.

Basically, the present embodiment describes the dynamic power allocation of the NR DMRS.

In the existing LTE, power control for PDSCH and CRS is performed in a semi-static manner through RRC signaling. However, in the DMRS symbol of the NR, since the DMRS is allocated UE-specific and the DMRS and data are multiplexed on the DMRS symbol, it is impossible to apply the existing LTE scheme to the same.

According to this embodiment, instead of directly adding the field for additional power allocation to the DCI, a method of indirectly controlling the power of the DMRS using the multiplexing information between the DMRS and the data will be described.

First, the base station gNB can lower the RRC setting value to the UE.

 ● Whether DMRS power control application

 ● Power control cycle of DMRS

 ● Number of power control applied ports of DMRS

 ● Power control according to DMRS configuration type (DMRS configuration type)

 ● Whether power control is applied according to the number of DMRS symbols (1-symbol DMRS or 2-symbol DMRS)

 ● Power control according to SU / MU-MIMO mode

Through the above-described upper layer signaling, the UE can receive all semi-static setting values for performing power control of the DMRS.

The terminal may then perform dynamic power allocation for the DMRS. Basically, since the DMRS symbol interval can be set as a 1-symbol interval or a 2-symbol interval, the power allocation method can be performed differently according to the length of the symbol interval.

Basically, there are two methods of performing dynamic on / off in the power-boosting or transmission power control process of the DMRS.

Controlling (explicitly signaling ) the transmit power of the DMRS using an additional 1 bit field in the DCI

● Controlling the transmission power of DMRS using existing information (implicit method)

In the present embodiment, it is assumed that power control / boosting of the DMRS is set semi-static first through the RRC signal. Therefore, additional power control / boosting of the DMRS is possible at any time during the interval in which the DMRS power-boosting is set.

It is possible to add a field indicating on / off of the power boosting of the DMRS in the DCI, but it is also possible to instruct the power boosting on / off in an implicit manner without the additional information.

In this case, rate matching information for multiplexing data and DMRS in the DMRS symbol interval can be used as information for indicating on / off of power boosting in an implicit manner.

At this time, the procedures for applying the power boosting message of the DMRS according to the manner in which the rate matching information between the data and the DMRS is transmitted are as follows.

1. DMRS-PDSCH rate matching information signaling using an RRC-based semi-static signaling scheme

Case 1: Transmission power control (explicit signaling) of DMRS using 1 bit of additional field in DCI

   ◆  It is possible to acquire the DMRS power control based on the rate matching information between the DMRS and the PDSCH through a field in the DCI.

That is, the rate matching information between the DMRS and the PDSCH and the DMRS power control information are both set through the RRC signaling, and the DMRS power boosting information for each slot is set in a separate field in the DCI Lt; / RTI > may be signaled to the terminal.

■ Case 2: Performing power control using existing information (implicit method)

   ◆  Performs DMRS power boosting without specifying any extra fields in the DCI. That is, the rate matching information between the DMRS and the PDSCH and the DMRS power control information are all set through the RRC signaling. In a range where both conditions are satisfied, the DMRS power control is necessarily performed You can use a predefined way to do that.

2. Rate matching information between the DMRS and the PDSCH through dynamic signaling via DCI is signaled

Case 1: Transmission power control (explicit signaling) of DMRS using 1 bit of additional field in DCI

   ◆  It is possible to acquire the DMRS power control based on the rate matching information between the DMRS and the PDSCH through a field in the DCI.

That is, the rate matching information between the DMRS and the PDSCH and the DMRS power control information are both set through the RRC signaling, and the DMRS power boosting information for each slot is set in a separate field in the DCI Lt; / RTI > may be signaled to the terminal.

■ Case 2: Performing power control using existing information (implicit method)

   ◆  Performs DMRS power boosting without specifying any extra fields in the DCI. The rate matching information between the PDSCH and the DMRS is utilized as signaling for indirectly applying power control since the power control of the DMRS is set to the RRC.

That is, since the UE can know the number of empty resource elements (empty REs) on the DMRS symbol through the rate matching information between the PDSCH and the DMRS, in this case, the number of DMRS resource elements (REs) May be preset to perform power boosting for the DMRS by the ratio of the number of resource elements (empty REs). The base station can transmit a power boosted DMRS to the UE.

Example  1-1. 1st DMRS  In the setting type (Comb + CS) DMRS and PDSCH  Liver Rate  Power allocation can be performed up to 2 times in an implicit manner using rate-matching information.

This embodiment proposes details of DMRS power boosting specific to the first DMRS set type. In this embodiment, the DMRS power boosting can be performed up to twice (expressed in 3 dB) in conjunction with rate matching information between the DMRS and the PDSCH. The basic operation method is shown in FIG. 7 below.

In this embodiment, the process of interpreting the rate matching information between the DMRS and the PDSCH into the DMRS power control information is as follows.

1) If no data is allocated to a blank resource element (empty RE) based on rate matching information between the DMRS and the PDSCH

A. The base station (gNB) does not perform PDSCH allocation on empty REs in the DMRS symbol

B. The base station gNB performs power boosting for the DMRS by the ratio of the number of empty resource elements (empty RE) to the number of DMRS resource elements (RE)

C. The UE assumes that the DMRS is power boosted by the ratio of the number of empty resource elements (empty RE) to the number of DMRS resource elements (RE) and performs channel estimation and recovery

2) Data is allocated to empty REs based on rate matching information between DMRS and PDSCH: DMRS power-boosting is not performed.

Example  1-2. Second DMRS  Setting type (2- FD - OCC ) DMRS and PDSCH  Liver Rate  Using the rate-matching information, the maximum Three times Power allocation can be performed.

This embodiment proposes details of DMRS power boosting specific to the second DMRS set type. In this embodiment, DMRS power boosting of up to 3 times (expressed as 4.8 dB or 4.77 dB in dB) can be performed in conjunction with rate matching information between the DMRS and the PDSCH. The basic operation method is shown in FIG. 8 below.

In this embodiment, the process of interpreting the rate matching information between the DMRS and the PDSCH into the DMRS power control information is as follows.

1) When data is not allocated to only one CDM group among two CDM groups through rate matching between the DMRS and PDSCH (only for CDM group 1 or CDM group 2 in FIG. 8) PDSCH is allocated)

A. The base station (gNB) does not perform PDSCH allocation only for a specific CDM group in a DMRS symbol

B. The base station (gNB) performs DMRS power boosting up to 2 times (3 dB) by the ratio of the number of empty resource elements (empty RE) to the number of DMRS resource elements (RE)

C. The UE assumes that only one CDM group is allocated a PDSCH and assumes that the DMRS is power boosted up to 3 dB irrespective of the position of the empty resource element (empty RE) Perform recovery

2) If no data is allocated to all of the two CDM groups through rate matching between the DMRS and the PDSCH (no PDSCH is assigned to both CDM group 1 or CDM group 2 in FIG. 8)

A. The base station (gNB) does not perform PDSCH allocation for all CDM groups in the DMRS symbol

B. The base station (gNB) performs DMRS power boosting up to 3 times (4.8dB) by the ratio of the number of empty REs to the number of DMRS resource elements (RE)

C. The UE assumes that all two CDM groups are composed of empty resource elements and performs channel estimation and recovery considering that DMRS is power boosting up to 4.8 dB.

3) Data is allocated to all two CDM groups through rate matching between DMRS and PDSCH: DMRS power boosting is not performed (CDM group 1 or CDM group 2 in FIG. 8) Lt; / RTI >

Considering Embodiments 1-1 and 1-2, the maximum value of the ratio of the number of empty resource elements (empty RE) to the number of DMRS resource elements (REs) on the DMRS symbol can be determined differently according to the DMRS setting type .

Example  1-3. DMRS  Depending on the configuration, additional power allocation is performed according to the density reduction ratio.

Here, additional power boosting can be performed according to the additional density reduction of the DMRS. For example, if the density of the front-loaded DMRS is set to 1/2, then the embodiment for the first DMRS setting type will be as in FIG. 9, and for the second DMRS setting type The embodiment is as shown in Fig.

At this time, in the embodiment of the first DMRS setting type of FIG. 9, a maximum of 2 * 2 = 4 times (6dB) is required if no PDSCH rate matching is performed on the remaining empty REs. To perform DMRS power boosting.

In the same manner, in the embodiment of the second DMRS setting type of FIG. 10, up to 2 * 3 = 6 times (7.8 dB) is achieved without performing PDSCH rate matching on the remaining empty REs. The DMRS power boosting is performed.

Therefore, when the DMRS density related information is signaled to the UE in addition to the PDSCH rate matching information, the gNB performs DMRS power-boosting using both of the above two information can do.

If the UE also receives both signals from the base station, it can combine them to derive the power-boosting value of the DMRS.

Example  1-4. DMRS  Power Boosting when a power boosting constraint value is set, a specific power 'irrespective of an available power' Px Quot; power boosting " value.

In this embodiment, the DMRS power boosting value is set to a specific value 'Px' irrespective of the maximum power-boosting value applied to the DMRS power-boosting embodiments 1, 1-1, 1-2, .

At this time, the value of 'Px' may be a preset value or the base station may set a specific 'Px' value to the terminal through upper layer signaling.

Example  1-5. MU- In the MIMO system  follow DMRS  Power Boosting (power boosting).

Currently, non-transparent multi-user pairing (MU pairing) is being discussed in NR MIMO.

The MU-MIMO of the existing LTE / LTE-A is transparent MU-MIMO and it can not know whether or not the terminal is currently paired with another terminal for a specific resource. In such a situation, DMRS power boosting can not be performed using only rate matching information.

For example, if it is assumed that the UE # 1 recognizes a blank resource element (empty RE) based on rate-matching information between the current PDSCH and the DMRS, then the DMRS port of the UE # And can be assigned to the corresponding empty resource element (empty RE).

At this time, in the case of using the transparent MU-MIMO scheme, the UE # 1 can not know whether or not the UE # 2 has assigned the DMRS port to the empty RE, Therefore, DMRS power boosting can not be used.

Therefore, in such a case, it is effective to directly add a field for indicating power-boosting of the DMRS in the DCI to instruct the terminal, as in the first embodiment.

However, in non-transparent multi-user pairing (MU pairing), the base station transmits the maximum number of DMRS ports to the UE or PDSCH rate matching information considering multi-user pairing (MU pairing) To the terminal. Based on the number of DMRS ports of the UE, the UE can know whether there is a multi-user pairing (MU pairing) with respect to the current DMRS symbol area. Therefore, the DMRS power boosting of the UE can be applied to the above-described embodiments 1-1 to 1-4.

That is, the base station gNB may not perform DMRS power-boosting considering a transparent / non-transparent MU-MIMO scheme, or may transmit at least the maximum number of DMRS ports to the target terminal DMRS power-boosting can be performed only when there is a power supply.

11 is a diagram illustrating a specific procedure by which a base station transmits a DMRS to a mobile station in this embodiment.

Referring to FIG. 11, the BS may determine the ratio of the empty resource element (empty RE) to the DMRS resource element within the DMRS symbol, that is, the symbol to which the DMRS can be allocated in the resource block (S1100). The base station transmits the DMRS to the terminal through the DMRS resource element, and transmits / receives data to / from the terminal through the blank resource element, that is, receives uplink data from the terminal or transmits downlink data to the terminal.

At this time, the ratio value of the blank resource element to the DMRS resource element may be determined through the information indicating the available resource element pattern available to the UE among the one or more effective resource element patterns configured by the base station.

The available resource element (available RE) basically means resource elements in which the DMRS is not allocated in the DMRS symbol. And the pattern for the effective resource element means bundle information for the corresponding effective resource element. At this time, depending on the DMRS setting type, the patterns of the effective resource elements may be different from each other.

This effective resource element pattern can also be referred to as a CDM (Code Division Multiplexing) group, and is not limited by terms or words. That is, the CDM group in the above-described embodiment can be interpreted to have the same meaning as the effective resource element pattern.

The effective resource element pattern may be composed of resource elements not allocated to the DMRS among the resource elements located on the DMRS symbol, that is, on the symbol to which the DMRS can be allocated in the resource block. The base station may configure one or more effective resource element patterns, and may transmit information indicating a valid resource element pattern available to the terminal to the terminal. At this time, information indicating a usable effective resource element pattern can be transmitted to the terminal through the downlink control information (DCI).

When the base station transmits information indicating the available resource element pattern that can be used by the terminal to the terminal, instead of using a separate independent field in the above-described downlink control information, And can be transmitted to the terminal.

The information indicating the available resource element pattern that can be used by the terminal may include information indicating the number of available resource element patterns available to the terminal. For example, the number of valid resource element patterns that can be used by the terminal may be one, two, or three, and the terminal may determine which effective resource element pattern is available based on the corresponding number information (eg, The first effective resource element pattern, the second effective resource element pattern, and the third effective resource element pattern), the first effective resource element pattern, the second effective resource element pattern, and the third effective resource element pattern).

In this case, for example, the ratio value of the blank resource element to the DMRS resource element may be determined as one of 1, 2, and 3. And the maximum value that the ratio value of the blank resource element to the DMRS resource element can have can be determined differently according to the DMRS setting type.

Further, the base station can determine the DMRS power increase based on the ratio value of the blank resource element to the DMRS resource element (S1110).

In this case, for example, when the DMRS setting type is the first DMRS setting type (Comb + CS), the maximum value of the ratio value of the blank resource element to the DMRS resource element is determined to be 2, and the maximum value of the DMRS power increase amount is 3 dB Can be determined.

As another example, when the DMRS setting type is the second DMRS setting type (2-FD-OCC), the maximum value of the ratio value of the blank resource element to the DMRS resource element is determined to be 3, and the maximum value of the DMRS power increase amount is 4.77 dB Can be determined.

Further, the base station can transmit the DMRS to the mobile station with power determined based on the DMRS power increase amount (S1120).

FIG. 12 is a diagram illustrating a specific procedure in which a terminal receives a DMRS from a base station in this embodiment.

Referring to FIG. 12, the UE can receive information on the ratio value of the empty resource element (empty RE) to the DMRS resource element in the DMRS symbol, i.e., a symbol to which the DMRS can be allocated in the resource block (S1200) . The terminal receives the DMRS from the base station through the DMRS resource element, and can transmit and receive data with the base station through the empty resource element, that is, receive downlink data from the base station or transmit uplink data to the base station.

At this time, the ratio value of the blank resource element to the DMRS resource element may be determined through the information indicating the available resource element pattern available to the UE among the one or more effective resource element patterns configured by the base station.

The effective resource element pattern may be composed of resource elements not allocated to the DMRS among the resource elements located on the DMRS symbol, that is, on the symbol to which the DMRS can be allocated in the resource block. The base station may configure one or more effective resource element patterns, and may transmit information indicating a valid resource element pattern available to the terminal to the terminal. At this time, information indicating a usable effective resource element pattern can be transmitted to the terminal through the downlink control information (DCI).

When receiving information indicating a usable available resource element pattern from the base station, the corresponding instruction information is transmitted to a field indicating antenna port information instead of using a separate independent field in the downlink control information May be included and received from the base station.

The information indicating the available resource element pattern that can be used by the terminal may include information indicating the number of available resource element patterns available to the terminal. For example, the number of valid resource element patterns that can be used by the terminal may be one, two, or three, and the terminal may determine which effective resource element pattern is available based on the corresponding number information (eg, The first effective resource element pattern, the second effective resource element pattern, and the third effective resource element pattern), the first effective resource element pattern, the second effective resource element pattern, and the third effective resource element pattern).

In this case, for example, the ratio value of the blank resource element to the DMRS resource element may be determined as one of 1, 2, and 3. And the maximum value that the ratio value of the blank resource element to the DMRS resource element can have can be determined differently according to the DMRS setting type.

In step S1210, the UE may receive the increased DMRS from the BS according to the DMRS power increase determined based on the ratio of the empty RE to the DMRS resource element.

In this case, for example, when the DMRS setting type is the first DMRS setting type, the maximum value of the ratio value of the blank resource element to the DMRS resource element is determined to be 2, and the maximum value of the DMRS power increase amount may be determined to be 3 dB.

As another example, when the DMRS setting type is the second DMRS setting type, the maximum value of the ratio value of the blank resource element to the DMRS resource element is determined to be 3, and the maximum value of the DMRS power increase amount may be determined to be 4.77 dB.

FIG. 13 is a diagram illustrating a configuration of a base station according to the present embodiments.

13, the base station 1300 includes a control unit 1310, a transmission unit 1320, and a reception unit 1330.

The controller 1310 determines the ratio of the blank resource element to the DMRS resource element in the DMRS symbol and determines the DMRS power increase amount based on the ratio value of the blank resource element to the DMRS resource element.

The base station transmits the DMRS to the terminal through the DMRS resource element, and transmits / receives data to / from the terminal through the blank resource element, that is, receives uplink data from the terminal or transmits downlink data to the terminal.

At this time, the ratio value of the blank resource element to the DMRS resource element may be determined through the information indicating the available resource element pattern available to the UE among the one or more effective resource element patterns configured by the base station.

The effective resource element pattern may be composed of resource elements not allocated to the DMRS among the resource elements located on the DMRS symbol, that is, on the symbol to which the DMRS can be allocated in the resource block. The base station may configure one or more effective resource element patterns, and may transmit information indicating a valid resource element pattern available to the terminal to the terminal. At this time, information indicating a usable effective resource element pattern can be transmitted to the terminal through the downlink control information (DCI).

When the base station transmits information indicating the available resource element pattern that can be used by the terminal to the terminal, instead of using a separate independent field in the above-described downlink control information, And can be transmitted to the terminal.

The information indicating the available resource element pattern that can be used by the terminal may include information indicating the number of available resource element patterns available to the terminal. For example, the number of valid resource element patterns that can be used by the terminal may be one, two, or three, and the terminal may determine which effective resource element pattern is available based on the corresponding number information (eg, The first effective resource element pattern, the second effective resource element pattern, and the third effective resource element pattern), the first effective resource element pattern, the second effective resource element pattern, and the third effective resource element pattern).

In this case, for example, the ratio value of the blank resource element to the DMRS resource element may be determined as one of 1, 2, and 3. And the maximum value that the ratio value of the blank resource element to the DMRS resource element can have can be determined differently according to the DMRS setting type.

For example, when the DMRS setting type is the first DMRS setting type, the maximum value of the ratio value of the blank resource element to the DMRS resource element is determined to be 2, and the maximum value of the DMRS power increase amount may be determined to be 3 dB.

As another example, when the DMRS setting type is the second DMRS setting type, the maximum value of the ratio value of the blank resource element to the DMRS resource element is determined to be 3, and the maximum value of the DMRS power increase amount may be determined to be 4.77 dB.

The transmitting unit 1320 and the receiving unit 1330 are used to transmit and receive signals, messages, and data necessary for carrying out the present invention to and from the terminal.

Specifically, the transmitter 1320 can transmit the DMRS to the terminal using the power determined based on the DMRS power increase determined by the controller 1310. [

FIG. 14 is a diagram illustrating a configuration of a terminal according to the present embodiments.

14, the terminal 1400 includes a receiving unit 1410, a control unit 1420, and a transmitting unit 1430.

The receiving unit 1410 receives information on the ratio value of the blank resource element with respect to the DMRS resource element in the DMRS symbol and increases the power according to the DMRS power increase amount determined on the basis of the ratio value of the blank resource element to the DMRS resource element Lt; RTI ID = 0.0 > DMRS < / RTI >

The terminal receives the DMRS from the base station through the DMRS resource element, and can transmit and receive data with the base station through the empty resource element, that is, receive downlink data from the base station or transmit uplink data to the base station.

At this time, the ratio value of the blank resource element to the DMRS resource element may be determined through the information indicating the available resource element pattern available to the UE among the one or more effective resource element patterns configured by the base station.

The effective resource element pattern may be composed of resource elements not allocated to the DMRS among the resource elements located on the DMRS symbol, that is, on the symbol to which the DMRS can be allocated in the resource block. The base station may configure one or more effective resource element patterns, and may transmit information indicating a valid resource element pattern available to the terminal to the terminal. At this time, information indicating a usable effective resource element pattern can be transmitted to the terminal through the downlink control information (DCI).

When the base station transmits information indicating the available resource element pattern that can be used by the terminal to the terminal, instead of using a separate independent field in the above-described downlink control information, And can be transmitted to the terminal.

The information indicating the available resource element pattern that can be used by the terminal may include information indicating the number of available resource element patterns available to the terminal. For example, the number of valid resource element patterns that can be used by the terminal may be one, two, or three, and the terminal may determine which effective resource element pattern is available based on the corresponding number information (eg, The first effective resource element pattern, the second effective resource element pattern, and the third effective resource element pattern), the first effective resource element pattern, the second effective resource element pattern, and the third effective resource element pattern).

In this case, for example, the ratio value of the blank resource element to the DMRS resource element may be determined as one of 1, 2, and 3. And the maximum value that the ratio value of the blank resource element to the DMRS resource element can have can be determined differently according to the DMRS setting type.

For example, when the DMRS setting type is the first DMRS setting type, the maximum value of the ratio value of the blank resource element to the DMRS resource element is determined to be 2, and the maximum value of the DMRS power increase amount may be determined to be 3 dB.

As another example, when the DMRS setting type is the second DMRS setting type, the maximum value of the ratio value of the blank resource element to the DMRS resource element is determined to be 3, and the maximum value of the DMRS power increase amount may be determined to be 4.77 dB.

The standard content or standard documents referred to in the above-mentioned embodiments constitute a part of this specification, for the sake of simplicity of description of the specification. Therefore, it is to be understood that the content of the above standard content and portions of the standard documents are added to or contained in the scope of the present invention.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

Claims (20)

A method for transmitting a demodulation reference signal (DMRS) to a terminal by a base station,
Determining a ratio of a blank resource element to a DMRS resource element within a DMRS symbol;
Determining a DMRS power increase based on the ratio value; And
And transmitting the DMRS to the terminal with power determined based on the DMRS power increase.
The method according to claim 1,
The ratio value may be,
1, 2 and 3, respectively.
The method according to claim 1,
The maximum value of the ratio value
DMRS setting type. ≪ Desc / Clms Page number 13 >
The method of claim 3,
If the DMRS setting type is the first DMRS setting type,
The maximum value of the ratio value is determined to be 2,
Wherein the maximum value of the DMRS power increase amount is determined to be 3 dB.
The method of claim 3,
If the DMRS setting type is the second DMRS setting type,
The maximum value of the ratio value is determined as 3,
And the maximum value of the DMRS power increase amount is determined to be 4.77 dB.
A method for receiving a demodulation reference signal (DMRS) from a base station,
Receiving information on a ratio value of a blank resource element to a DMRS resource element in a DMRS symbol; And
And receiving from the base station a power increased DMRS according to the determined increase in DMRS power based on the ratio value.
The method according to claim 6,
The ratio value may be,
1, 2 and 3, respectively.
The method according to claim 6,
The maximum value of the ratio value
DMRS setting type. ≪ Desc / Clms Page number 13 >
9. The method of claim 8,
If the DMRS setting type is the first DMRS setting type,
The maximum value of the ratio value is determined to be 2,
Wherein the maximum value of the DMRS power increase amount is determined to be 3 dB.
9. The method of claim 8,
If the DMRS setting type is the second DMRS setting type,
The maximum value of the ratio value is determined as 3,
And the maximum value of the DMRS power increase amount is determined to be 4.77 dB.
A base station for transmitting a Demodulation Reference Signal (DMRS) to a terminal,
A controller for determining a ratio of a blank resource element to a DMRS resource element in the DMRS symbol and determining an increase amount of the DMRS power based on the ratio value; And
And a transmitter for transmitting the DMRS to the terminal using the power determined based on the DMRS power increase amount.
12. The method of claim 11,
The ratio value may be,
1, 2 and 3, respectively.
12. The method of claim 11,
The maximum value of the ratio value
And is determined differently depending on the DMRS setting type.
14. The method of claim 13,
If the DMRS setting type is the first DMRS setting type,
The maximum value of the ratio value is determined to be 2,
Wherein the maximum value of the DMRS power increase amount is determined to be 3 dB.
14. The method of claim 13,
If the DMRS setting type is the second DMRS setting type,
The maximum value of the ratio value is determined as 3,
And the maximum value of the DMRS power increase amount is determined to be 4.77 dB.
A terminal for receiving a demodulation reference signal (DMRS) from a base station,
And a receiving unit for receiving information on the ratio value of the empty resource element to the DMRS resource element in the DMRS symbol and receiving the DMRS having the increased power according to the determined increase amount of the DMRS power based on the ratio value .
17. The method of claim 16,
The ratio value may be,
1, 2 and 3, respectively.
17. The method of claim 16,
The maximum value of the ratio value
And is determined differently according to the DMRS setting type.
19. The method of claim 18,
If the DMRS setting type is the first DMRS setting type,
The maximum value of the ratio value is determined to be 2,
Wherein the maximum value of the DMRS power increase amount is determined to be 3 dB.
19. The method of claim 18,
If the DMRS setting type is the second DMRS setting type,
The maximum value of the ratio value is determined as 3,
And the maximum value of the DMRS power increase amount is determined to be 4.77 dB.

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