WO2019103550A1

WO2019103550A1 - Method for transmitting or receiving downlink signal between terminal and base station in wireless communication system, and apparatus supporting same

Info

Publication number: WO2019103550A1
Application number: PCT/KR2018/014609
Authority: WO
Inventors: 이길봄
Original assignee: 엘지전자 주식회사
Priority date: 2017-11-24
Filing date: 2018-11-26
Publication date: 2019-05-31

Abstract

Disclosed are a method for transmitting or receiving a downlink signal between a terminal and a base station in a wireless communication system, and an apparatus supporting the same. According to one embodiment applicable to the present invention, a terminal may receive a downlink signal including a phase tracking reference signal (PTRS) transmitted through multiple subcarriers for a demodulation reference signal (DMRS) port index assigned to the terminal. Here, the terminal may receive the PTRS, using an orthogonal cover code (OCC) determined on the basis of the DMRS port index assigned to the terminal.

Description

A method for transmitting and receiving a downlink signal between a terminal and a base station in a wireless communication system and a device supporting the same

The following description relates to a wireless communication system and a method for transmitting and receiving a downlink signal between a terminal and a base station in a wireless communication system and a device supporting the same.

Wireless access systems are widely deployed to provide various types of communication services such as voice and data. In general, a wireless access system is a multiple access system capable of supporting communication with multiple users by sharing available system resources (bandwidth, transmission power, etc.). Examples of multiple access systems include a code division multiple access (CDMA) system, a frequency division multiple access (FDMA) system, a time division multiple access (TDMA) system, an orthogonal frequency division multiple access (OFDMA) system, a single carrier frequency division multiple access) systems.

In addition, as more and more communication devices are required to have larger communication capacity, there is a need for improved mobile broadband communication over existing radio access technology (RAT). Also, massive MTC (Machine Type Communications), which provides various services by connecting multiple devices and objects, is also considered in the next generation communication. In addition, a communication system design considering a service / UE sensitive to reliability and latency is being considered.

The introduction of the next-generation RAT, which takes into account such improved mobile broadband communications, massive MTC, and Ultra-Reliable and Low Latency Communication (URLLC), is being discussed.

Particularly, considering a method of transmitting and receiving signals through various frequency bands, the concept of a phase tracking reference signal (PT-RS) for estimating the phase noise between the UE and the base station in the various frequency bands is various Are being discussed.

An object of the present invention is to provide a method for transmitting and receiving a downlink signal between a terminal and a base station in a wireless communication system and devices supporting the same.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not intended to limit the invention to the particular form disclosed. &Lt; / RTI >

The present invention provides a method for transmitting / receiving a downlink signal between a terminal and a base station in a wireless communication system and apparatuses therefor.

In one aspect of the present invention, there is provided a method of receiving a downlink signal in a wireless communication system, the method comprising: receiving information on a demodulation reference signal (DMRS) port index allocated to the terminal from a base station; And receiving a downlink signal including a phase tracking reference signal (PT-RS) transmitted over a plurality of sub-carriers for the allocated DMRS port index, the PT- (OCC), and the OCC is determined based on the allocated DMRS port index.

In the present invention, the PT-RS may be received through a plurality of second resource blocks spaced apart from each other by a predetermined interval among a plurality of consecutive first resource blocks.

At this time, the location of the second resource blocks among the plurality of consecutive first resource blocks is determined based on at least one of the physical cell identifier, the virtual cell identifier, the terminal identifier, or the information indicated by the upper layer signaling Can be determined.

Alternatively, the location of a plurality of sub-carriers for receiving the PT-RS in one of the second resource blocks may be determined based on a demodulation reference signal port index allocated to the UE from the BS.

Alternatively, the location of a plurality of sub-carriers for which the PT-RS is received in one of the second resource blocks may be determined based on a physical cell identifier, a virtual cell identifier, May be determined based on one or more of the information indicated by the higher layer signaling.

In the present invention, the method may further include receiving information on the number of CDRS (Code Division Multiplexing) groups from the base station. The MS determines whether there is a PT-RS transmitted to another MS based on at least one of the number of the DMRS CDM groups and the DMRS port index assigned to the MS, and whether the PT-RS transmitted to the MS is power-boosted , And can receive the downlink signal including the PT-RS based on the determination.

For example, the MS receiving the information indicating that the number of the DMRS CDM group is 1 from the BS can receive the downlink signal on the assumption that there is no PT-RS transmitted from the BS to another MS.

More specifically, assuming that there is no PT-RS transmitted from the BS to another MS, the MS receiving the downlink signal transmits data in the resource area for the PT-RS of the DMRS CDM group not associated with the MS It is possible to receive the downlink signal.

At this time, upon receiving the information indicating that the number of the DMRS CDM group is 1 from the BS, the terminal determines whether the PT-RS is in a state of being connected to the DMRS CDM group RS, the PT-RS, and the PT-RS.

As another example, when receiving information indicating that a plurality of DMRS CDM groups are received from the BS and all the DMRS port indices allocated to the MS are included in one CDM group, the MS transmits PT-RS The downlink signal can be received.

More specifically, the terminal receiving the downlink signal on the assumption that there is a PT-RS transmitted from the base station to another terminal transmits one or more PT-RSs having an association with one or more DMRS CDM groups not associated with the terminal, It is possible to receive the downlink signal on the assumption that data is not transmitted in the resource region for RS.

At this time, when receiving the information indicating that the number of the DMRS CDM group is N from the BS and all the DMRS port indexes allocated to the UE are included in one DMRS CDM group, the UE transmits one or more PTs RS and receive the downlink signal including the PT-RS under the assumption that the power boosting level of the PT-RS based on the RS ports is 10 * log10N (dB).

As another example, if it is determined that all the DMRS port indices allocated to the UE are included in different DMRS CDM groups and the QCLs of the DMRS ports included in the different DMRS CDM groups are received, (Qausi-co-Located) sources are all the same, there is no PT-RS transmitted from the base station to another terminal, and the number of PT-RS ports assigned to the terminal is one, Lt; / RTI >

In this case, when receiving the information indicating that the number of the DMRS CDM groups is plural, the DMRS port index allocated to the UE is included in the different DMRS CDM group, and the QCL sources of the DMRS ports included in the different DMRS CDM groups are all The same terminal can receive the downlink signal including the PT-RS on the assumption that the PT-RS is transmitted without power boosting based on one or more PT-RS ports associated with another DMRS CDM group. In this case, the terminal borrows power from another PT-RS port and does not expect the power of the PT-RS allocated to the terminal to be boosted.

As another example, when receiving information indicating that a plurality of DMRS CDM group numbers are received from the BS, the DMRS port index allocated to the MS is included in different DMRS CDM groups, and the QCLs of the DMRS ports included in the different DMRS CDM groups The UE having a different Qausi-co-Located source does not have a PT-RS port transmitted from the base station to another terminal, and the number of PT-RS ports allocated to the terminal is two, can do. In this case, the terminal borrows power from another PT-RS port and expects the power of the PT-RS to be boosted. In this case, it is valid only when the number of DL PT-RS ports is indicated by 2 or more in the TCI state to the terminal. If the number of DL PT-RS ports is 1 through the TCI state, the UE does not expect the power boosting.

In the present invention, the length of the OCC may be set equal to the number of PT-RS ports sharing a resource region for the PT-RS.

For example, the number of PT-RS ports sharing a resource region for the PT-RS may be the same as the number of sub-carriers for which the PT-RS is received in one resource block.

According to another aspect of the present invention, there is provided a communication apparatus for receiving a downlink signal in a wireless communication system, the apparatus comprising: a memory; And a processor connected to the memory, wherein the processor receives information on a demodulation reference signal (DMRS) port index allocated to the terminal from the base station; And a phase tracking reference signal (PT-RS) transmitted over a plurality of sub-carriers for the allocated DMRS port index, the PT-RS being configured to receive an orthogonal cover code (OCC), and the OCC is determined based on the assigned DMRS port index.

According to still another aspect of the present invention, there is provided a communication apparatus for transmitting a downlink signal in a wireless communication system, comprising: a memory; And a processor operatively connected to the memory, wherein the processor transmits information on a demodulation reference signal (DMRS) port index assigned to one or more terminals to the one or more terminals; And transmitting the downlink signal including the at least one terminal's phase tracking reference signal (PT-RS) to the at least one terminal, wherein the one or more terminal-specific PT- (OCC) associated with a plurality of subcarriers for an allocated DMRS port index, the OCC associated with each of the one or more UEs is based on a DMRS port index allocated to the one or more UEs And a communication device.

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed and will become apparent to those skilled in the art from the following detailed description, Can be derived and understood based on the description.

According to the embodiments of the present invention, the following effects are obtained.

According to the present invention, the UE can receive a PT-RS from a Node B via a plurality of sub-carriers per resource block. Accordingly, the UE can more reliably measure the phase error (or phase noise) with respect to the base station.

In addition, the PT-RS is transmitted based on the OCC (or OCC is applied), so that the PT-RS collision between the terminals can be minimized.

Also, according to the present invention, the UE can recognize whether there is a PT-RS transmitted from a base station to another UE based on information on the number of DMRS CDM groups, and can receive a downlink signal have. That is, even if the transmission of the PT-RS for the other terminal is not informed through separate signaling, the terminal can indirectly know this. For example, when the DMRS ports # 0 and # 2 are allocated to the terminal based on the DMRS configuration 1, the terminal may not assume that it is multiplexed with the same time and frequency resources as the other terminals. Here, the DMRS ports # 0, # 1, # 2, # 3, and # 11 may mean DMRS ports # 1000, # 1001, # 1002, #, # 1011 of the 3GPP NR standard.

The effects obtainable in the embodiments of the present invention are not limited to the effects mentioned above, and other effects not mentioned can be obtained from the description of the embodiments of the present invention described below by those skilled in the art Can be clearly understood and understood. In other words, undesirable effects of implementing the present invention can also be obtained by those skilled in the art from the embodiments of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. It is to be understood, however, that the technical features of the present invention are not limited to the specific drawings, and the features disclosed in the drawings may be combined with each other to constitute a new embodiment. Reference numerals in the drawings refer to structural elements.

1 is a diagram for explaining a physical channel and a signal transmission method using the same.

2 is a view showing a self-contained slot structure applicable to the present invention.

FIGS. 3 and 4 are views showing typical connection methods of the TXRU and the antenna element.

5 is a simplified view of a hybrid beamforming structure in terms of TXRU and physical antennas according to an example of the present invention.

6 is a diagram briefly illustrating a beam sweeping operation for a synchronization signal and system information in a downlink (DL) transmission process according to an exemplary embodiment of the present invention.

7 is a diagram illustrating a time domain pattern of a PT-RS applicable to the present invention.

Figure 8 is a simplified representation of two types of DMRS settings applicable to the present invention.

FIG. 9 is a diagram simply showing an example of a front loaded DMRS of the first DMRS setting type applicable to the present invention.

10 to 13 are views showing various examples of Localized PT-RS according to the present invention.

14 is a diagram illustrating an example of a distributed PT-RS according to an exemplary embodiment of the present invention.

FIG. 15 is a view for simply transmitting and receiving a downlink signal between a terminal and a base station according to an embodiment of the present invention. FIG. 16 is a flowchart briefly illustrating an operation for receiving a downlink signal according to the present invention, 17 is a flowchart briefly illustrating an operation of transmitting a downlink signal by a base station according to the present invention.

18 is a diagram showing a configuration of a terminal and a base station in which the proposed embodiments can be implemented.

The following embodiments are a combination of elements and features of the present invention in a predetermined form. Each component or characteristic may be considered optional unless otherwise expressly stated. Each component or feature may be implemented in a form that is not combined with other components or features. In addition, some of the elements and / or features may be combined to form an embodiment of the present invention. The order of the operations described in the embodiments of the present invention may be changed. Some configurations or features of certain embodiments may be included in other embodiments, or may be replaced with corresponding configurations or features of other embodiments.

In the description of the drawings, there is no description of procedures or steps that may obscure the gist of the present invention, nor is any description of steps or steps that can be understood by those skilled in the art.

Throughout the specification, when an element is referred to as " comprising " or " including ", it is meant that the element does not exclude other elements, do. Also, the terms " part, " " module, " and " module " in the specification mean units for processing at least one function or operation, Lt; / RTI > Also, the terms " a or ", " one ", " the ", and the like are synonyms in the context of describing the invention (particularly in the context of the following claims) May be used in a sense including both singular and plural, unless the context clearly dictates otherwise.

The embodiments of the present invention have been described herein with reference to a data transmission / reception relationship between a base station and a mobile station. Here, the base station is meaningful as a terminal node of a network that directly communicates with a mobile station. The specific operation described herein as performed by the base station may be performed by an upper node of the base station, as the case may be.

That is, various operations performed for communication with a mobile station in a network consisting of a plurality of network nodes including a base station may be performed by a base station or other network nodes other than the base station. The 'base station' may be replaced by a term such as a fixed station, a Node B, an eNode B, a gNode B, an Advanced Base Station (ABS), or an access point .

Also, in the embodiments of the present invention, a terminal may be a user equipment (UE), a mobile station (MS), a subscriber station (SS), a mobile subscriber station (MSS) , A mobile terminal, or an advanced mobile station (AMS).

Also, the transmitting end refers to a fixed and / or mobile node providing data service or voice service, and the receiving end means a fixed and / or mobile node receiving data service or voice service. Therefore, in the uplink, the mobile station may be the transmitting end and the base station may be the receiving end. Similarly, in a downlink, a mobile station may be a receiving end and a base station may be a transmitting end.

Embodiments of the present invention may be supported by standard documents disclosed in at least one of the following IEEE 802.xx systems, 3rd Generation Partnership Project (3GPP) systems, 3GPP LTE systems, 3GPP 5G NR systems, and 3GPP2 systems: In particular, embodiments of the present invention may be supported by documents 3GPP TS 38.211, 3GPP TS 38.212, 3GPP TS 38.213, 3GPP TS 38.321 and 3GPP TS 38.331. That is, self-explaining steps or parts not described in the embodiments of the present invention can be described with reference to the documents. In addition, all terms disclosed in this document may be described by the standard document.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following detailed description, together with the accompanying drawings, is intended to illustrate exemplary embodiments of the invention and is not intended to represent the only embodiments in which the invention may be practiced.

In addition, the specific terms used in the embodiments of the present invention are provided to facilitate understanding of the present invention, and the use of such specific terms can be changed to other forms without departing from the technical idea of the present invention .

Hereinafter, a 3GPP NR system will be described as an example of a radio access system in which embodiments of the present invention can be used.

The following description is to be understood as illustrative and non-limiting, such as code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), orthogonal frequency division multiple access (OFDMA), single carrier frequency division multiple access And can be applied to various wireless connection systems.

In order to clarify the technical features of the present invention, embodiments of the present invention will be described mainly in 3GPP NR system. However, the embodiment proposed in the present invention can be similarly applied to other wireless systems (e.g., 3GPP LTE, IEEE 802.16, IEEE 802.11, etc.).

1. NR 1. NR 시스템system

1.1 물리 채널들 및 이를 이용한 신호 송수신 방법1.1 Physical Channels and Signal Transmission and Reception Method Using It

In a wireless access system, a terminal receives information from a base station through a downlink (DL) and transmits information to a base station through an uplink (UL). The information transmitted and received between the base station and the terminal includes general data information and various control information, and there are various physical channels depending on the type / use of the information transmitted / received.

FIG. 1 is a view for explaining physical channels that can be used in embodiments of the present invention and a signal transmission method using the same.

The terminal that is powered on again after power is turned off or a terminal that has entered a new cell performs an initial cell search operation such as synchronizing with the base station in step S11. To this end, a mobile station receives a primary synchronization channel (P-SCH) and a secondary synchronization channel (S-SCH) from a base station, synchronizes with the base station, and acquires information such as a cell ID.

Then, the terminal can receive the physical broadcast channel (PBCH) signal from the base station and acquire the in-cell broadcast information.

Meanwhile, the UE can receive the downlink reference signal (DL RS) in the initial cell search step to check the downlink channel state.

Upon completion of the initial cell search, the UE receives a physical downlink control channel (PDCCH) and a physical downlink control channel (PDSCH) according to physical downlink control channel information in step S12, Specific system information can be obtained.

Thereafter, the terminal may perform a random access procedure such as steps S13 to S16 to complete the connection to the base station. To this end, the UE transmits a preamble through a Physical Random Access Channel (PRACH) (S13), and transmits a RAR (preamble) to the preamble through the physical downlink control channel and the corresponding physical downlink shared channel Random Access Response) (S14). The MS transmits a Physical Uplink Shared Channel (PUSCH) using the scheduling information in the RAR (S15), and receives a Physical Downlink Control Channel (PDCCH) signal and a corresponding Physical Downlink Shared Channel ) (S16).

The UE having performed the procedure described above transmits a physical downlink control channel signal and / or physical downlink shared channel signal (S17) and a physical uplink shared channel (PUSCH: physical (S18) of an uplink shared channel (PUCCH) signal and / or a physical uplink control channel (PUCCH) signal.

Control information transmitted from the UE to the Node B is collectively referred to as uplink control information (UCI). The UCI includes HARQ-ACK / NACK (Hybrid Automatic Repeat and Acknowledgment / Negative ACK), SR (Scheduling Request), CQI (Channel Quality Indication), PMI (Precoding Matrix Indication), RI ) Information.

In the NR system, the UCI is generally transmitted periodically via the PUCCH, but may be transmitted over the PUSCH according to an embodiment (e.g., when control information and traffic data are to be transmitted simultaneously). Also, according to a request / instruction of the network, the UE can periodically transmit the UCI through the PUSCH.

1.2.1.2. 뉴머롤로지들Nemer Rollers ( ( NumerologiesNumerologies ))

In the NR system to which the present invention is applicable, various OFDM (Orthogonal Frequency Division Multiplexing) neighbors are supported as shown in the following table. At this time, the ringing parameter and the cyclic prefix information for each carrier bandwidth part can be signaled for the downlink (DL) or uplink (UL), respectively. In one example, the neighbors of the downlink carrier bandwidth part and cyclic prefix information may be signaled via higher layer signaling DL-BWP-mu and DL-MWP-cp . In another example, the neighbors of the uplink carrier bandwidth part and the cyclic prefix information may be signaled via higher layer signaling UL-BWP-mu and UL-MWP-cp .

1.3. 프레임 구조1.3. Frame structure

The downlink and uplink transmissions are composed of 10 ms long frames. The frame may be composed of 10 sub-frames each having a length of 1 ms. At this time, the number of consecutive OFDM symbols for each subframe is

to be.

Each frame may be composed of two half frames having the same size. At this time, each half-frame may be composed of sub-frames 0 - 4 and 5 - 9, respectively.

For the sub-carrier spacing [mu] or the resulting sub-carrier spacing [mu], the slots are arranged in ascending order within one sub-frame

Are numbered in ascending order within one frame

As shown in FIG. At this time, the number of consecutive OFDM symbols in one slot (

) Can be determined according to the cyclic prefix as shown in the following table. A starting slot in one subframe (

) Is the starting OFDM symbol (

) And the time dimension. Table 2 shows the number of OFDM symbols per slot / per frame / subframe for a normal cyclic prefix, and Table 3 shows the number of OFDM symbols per slot / frame / subframe for an extended cyclic prefix. Represents the number of OFDM symbols per subframe.

In the NR system to which the present invention can be applied, a self-contained slot structure can be applied with the slot structure as described above.

In FIG. 2, a hatched region (for example, symbol index = 0) represents a downlink control region, and a black region (for example, symbol index = 13) represents an uplink control region. Other areas (eg, symbol index = 1 to 12) may be used for downlink data transmission or for uplink data transmission.

According to this structure, the base station and the UE can sequentially perform DL transmission and UL transmission in one slot, and can transmit and receive DL data in the one slot and transmit / receive UL ACK / NACK thereto. As a result, this structure reduces the time it takes to retransmit data when a data transmission error occurs, thereby minimizing the delay in final data transmission.

In such an autonomous slot structure, a time gap of a certain time length is required for the base station and the UE to switch from the transmission mode to the reception mode or to switch from the reception mode to the transmission mode. For this, some OFDM symbols at the time of switching from DL to UL in the self-supporting slot structure may be set as a guard period (GP).

In the above description, the case where the self-supporting slot structure includes both the DL control region and the UL control region has been described, but the control regions may be selectively included in the self-supporting slot structure. In other words, the self-supporting slot structure according to the present invention may include not only the DL control area and the UL control area but also the DL control area or the UL control area as shown in FIG.

As an example, a slot may have various slot formats. At this time, the OFDM symbol of each slot can be classified into a downlink (denoted by 'D'), a flexible (denoted by 'X'), and an uplink (denoted by 'U').

Therefore, it can be assumed that in the downlink slot, the UE generates downlink transmission only in 'D' and 'X' symbols. Similarly, in the uplink slot, the UE can assume that the uplink transmission occurs only in the 'U' and 'X' symbols.

1.4. 아날로그 1.4. analog 빔포밍Beam forming (Analog (Analog beamforming보형링 ))

In the millimeter wave (mmW), the wavelength is short, and it is possible to install a plurality of antenna elements in the same area. That is, since the wavelength is 1 cm in the 30 GHz band, a total of 100 antenna elements can be provided when a 2-dimensional array is arranged at intervals of 0.5 lambda (wavelength) on a panel of 5 * 5 cm. Accordingly, in a millimeter wave (mmW), a plurality of antenna elements can be used to increase the beamforming (BF) gain to increase the coverage or increase the throughput.

At this time, each antenna element may include TXRU (Transceiver Unit) so that transmission power and phase can be adjusted for each antenna element. Thus, each antenna element can perform independent beamforming for each frequency resource.

However, installing a TXRU in all 100 antenna elements has a problem in terms of cost effectiveness. Therefore, a scheme of mapping a plurality of antenna elements to one TXRU and adjusting the direction of a beam with an analog phase shifter is considered. Such an analog beamforming method has a disadvantage in that frequency selective beamforming is difficult because only one beam direction can be generated in all bands.

As a solution to this, a hybrid beamforming (hybrid BF) having B TXRUs that are fewer than Q antenna elements as an intermediate form of digital beamforming and analog beamforming can be considered. In this case, although there is a difference depending on a connection method of B TXRU and Q antenna elements, the direction of a beam that can be transmitted at the same time may be limited to B or less.

FIGS. 3 and 4 are views showing typical connection methods of the TXRU and the antenna element. Here, the TXRU virtualization model shows the relationship between the output signal of the TXRU and the output signal of the antenna element.

3 is a diagram illustrating a manner in which a TXRU is connected to a sub-array. In the case of FIG. 3, the antenna element is connected to only one TXRU.

4 is a diagram illustrating a manner in which a TXRU is connected to all antenna elements. In the case of Figure 4, the antenna element is connected to all TXRUs. At this time, the antenna element requires a separate adder as shown in FIG. 4 to be connected to all TXRUs.

In Figures 3 and 4, W represents a phase vector multiplied by an analog phase shifter. That is, W is a main parameter for determining the direction of the analog beamforming. Here, the mapping between the CSI-RS antenna port and the TXRUs may be 1: 1 or 1: to-many.

According to the configuration of FIG. 3, there is a disadvantage in that beam focusing is difficult to focus, but the entire antenna configuration can be configured at a low cost.

According to the configuration of FIG. 4, there is an advantage that focusing of beam forming is easy. However, since TXRU is connected to all antenna elements, there is a disadvantage that the total cost increases.

When a plurality of antennas are used in the NR system to which the present invention is applicable, a hybrid beamforming technique combining digital beamforming and analog beamforming can be applied. At this time, the analog beamforming (or RF (Radio Frequency) beamforming) means an operation of performing precoding (or combining) in the RF stage. In the hybrid beamforming, the baseband stage and the RF stage perform precoding (or combining), respectively. This has the advantage of achieving performance close to digital beamforming while reducing the number of RF chains and the number of digital-to-analog (or analog-to-digital) converters.

For convenience of explanation, the hybrid beamforming structure may be represented by N transceiver units (TXRU) and M physical antennas. At this time, the digital beamforming for the L data layers to be transmitted by the transmitting end may be represented by an N * L (N by L) matrix. The converted N digital signals are then converted to an analog signal through a TXRU, and an analog beamforming represented by an M * N (M by N) matrix is applied to the converted signal.

5 is a simplified view of a hybrid beamforming structure in terms of TXRU and physical antennas according to an example of the present invention. In this case, the number of digital beams is L and the number of analog beams is N in FIG.

In addition, in the NR system to which the present invention is applicable, a base station is designed to change the analog beamforming in units of symbols, and a method of supporting more efficient beamforming to a terminal located in a specific area is considered. As shown in FIG. 9, when defining N TXRU and M RF antennas as one antenna panel, the NR system according to the present invention includes a plurality of antenna panels to which independent hybrid beamforming is applicable To be introduced.

As described above, when the base station utilizes a plurality of analog beams, an analog beam advantageous for signal reception may be different for each terminal. Accordingly, in the NR system to which the present invention is applicable, the base station applies a different analog beam for each symbol within a specific slot (at least a synchronous signal, system information, paging, etc.) Beam sweeping operation is being considered to enable the beam sweeping.

6, a physical resource (or a physical channel) through which system information of an NR system applicable to the present invention is transmitted in a broadcasting mode is referred to as an xPBCH (physical broadcast channel). At this time, analog beams belonging to different antenna panels within one symbol can be transmitted simultaneously.

6, in the NR system to which the present invention is applicable, a reference signal (reference signal) transmitted by applying a single analog beam (corresponding to a specific antenna panel) (Beam RS, BRS), which is an RS, is being discussed. The BRS may be defined for a plurality of antenna ports, and each antenna port of the BRS may correspond to a single analog beam. At this time, unlike the BRS, the synchronization signal or the xPBCH can be transmitted by applying all the analog beams in the analog beam group so that an arbitrary terminal can receive it well.

1.5. PT-1.5. PT- RSRS (Phase Tracking Reference Signal) (Phase Tracking Reference Signal)

The phase noise associated with the present invention will be described. The jitter on the time axis appears as phase noise on the frequency axis. This phase noise randomly changes the phase of the received signal on the time axis as shown in the following equation.

In Equation (1)

The parameters represent the phase rotation due to the received signal, the time base signal, the frequency axis signal, and the phase noise, respectively. When the received signal in Equation (1) undergoes a DFT (Discrete Fourier Transform) process, the following Equation (2) is derived.

In Equation (2)

The parameters represent Common Phase Error (CPE) and Inter Cell Interference (ICI), respectively. At this time, the larger the correlation between the phase noise is, the larger the CPE of Equation (2) becomes. This CPE is a type of CFO (Carrier Frequency Offset) in the wireless LAN system, but CPE and CFO can be similarly analyzed in terms of phase noise in the terminal.

The UE estimates the CPE / CFO and removes the phase noise CPE / CFO on the frequency axis. The process of estimating the CPE / CFO for the received signal by the UE must be performed in order to precisely decode the received signal. Accordingly, the base station can transmit a predetermined signal to the terminal so that the terminal can accurately estimate the CPE / CFO. This signal is a signal for estimating the phase noise, and may be a pilot signal shared in advance between the terminal and the base station And the data signal may be a changed or duplicated signal. Hereinafter, a series of signals for estimating phase noise are collectively referred to as a phase compensation reference signal (PCRS), a phase noise reference signal (PNRS), or a phase tracking reference signal (PT-RS). Hereinafter, for convenience of explanation, all of the configurations are collectively referred to as PT-RS.

1.5.1. The time domain pattern (or time density)

As shown in FIG. 7, the PT-RS may have a different pattern according to an applied modulation and coding scheme (MCS) level.

As shown in FIG. 7 and Table 4, the PT-RS can be mapped and transmitted in different patterns according to the applied MCS level.

If the above configuration is more generalized, the time domain pattern (or time density) of the PT-RS can be defined as shown in the following table.

At this time, time density 1 corresponds to Pattern # 1 in FIG. 7, time density 2 corresponds to Pattern # 2 in FIG. 7, and time density 4 corresponds to Pattern # 3 in FIG.

The parameters ptrs-MCS1, ptrs-MCS2, ptrs-MCS3, ptrs-MCS4 constituting Table 5 can be defined by higher layer signaling.

1.5.2. The frequency domain pattern (or frequency density)

The PT-RS according to the present invention can be mapped to one subcarrier per one RB (Resource Block), one subcarrier per two RBs, or one subcarrier per four RBs. At this time, the frequency domain pattern (or frequency density) of the PT-RS may be set according to the size of the scheduled bandwidth.

For example, it may have frequency densities as shown in Table 6 depending on the scheduled bandwidth.

Here, the frequency density 1 corresponds to a frequency domain pattern in which the PT-RS is mapped to one subcarrier per 1 RB and transmitted, and the frequency density is 1/2, and the PT-RS is mapped to one subcarrier every two RBs, And a frequency density of 1/4 corresponds to a frequency domain pattern in which the PT-RS is mapped to one subcarrier every four RBs and transmitted.

The frequency domain pattern (or frequency density) of the PT-RS can be defined as shown in the following table.

At this time, the frequency density 2 corresponds to a frequency domain pattern in which the PT-RS is mapped to one subcarrier every two RBs, and the frequency density 4 corresponds to a frequency at which the PT-RS is mapped to one subcarrier every four RBs, It can correspond to the area pattern.

In the above configuration, N _RB0 and N _{RB1, which} are reference values of the scheduled bandwidth for determining the frequency density, can be defined by higher layer signaling.

1.6. DMRS (Demodulation Reference Signal)1.6. DMRS (Demodulation Reference Signal)

In the NR system to which the present invention is applicable, the DMRS can be transmitted and received in a frond load structure. Alternatively, an additional DMRS (additional DMRS) other than the DMRS to be transmitted may be additionally transmitted / received.

Front loaded DMRS can support fast decoding. The first OFDM symbol carrying the front loaded DMRS may be determined as a third (eg l = 2) or a fourth OFDM symbol (eg l = 3). The first FODM symbol location may be indicated by a PBCH (Physical Broadcast Channel).

The number of OFDM symbols occupied by the front loaded DMRS can be indicated by a combination of DCI (Downlink Control Information) and RRC (Radio Resource Control) signaling.

Additional DMRS can be configured for high speed terminals. The additional DMRS may be located in the middle / last symbol (s) in the slot. If one Front loaded DMRS symbol is set, the Additional DMRS can be assigned to 0 to 3 OFDM symbols. If two Front loaded DMRS symbols are set, the additional DMRS can be assigned to zero or two OFDM symbols.

A front loaded DMRS is composed of two types, one of which can be indicated via higher layer signaling (eg RRC signaling).

In Fig. 8, P0 to P11 correspond to port numbers 1000 to 1011, respectively. Among the two types of DMRS setting types, the DMRS setting type that is substantially set for the UE can be indicated by an upper layer signaling (e.g., RRC).

In case of the first DMRS configuration type 1, the front loaded DMRS can be classified according to the number of OFDM symbols allocated as follows.

The number of OFDM symbols to which the first DMRS configuration type (DMRS configuration type 1) and the front loaded DMRS are allocated = 1

Up to four ports (e.g., P0 to P3) may be multiplexed based on the length-2 F-Frequency-Code Division Multiplexing (CDM) and Frequency Division Multiplexing (FDM) methods. The RS density can be set to 6 REs per port in the RB (Resource Block).

The number of OFDM symbols to which the first DMRS configuration type (DMRS configuration type 1) and the front loaded DMRS are allocated = 2

Up to eight ports (e.g., P0 to P7) may be multiplexed based on length-2 F-CDM, length-2 T-Time-Code Division Multiplexing (CDM) and FDM methods. Here, when the existence of the PT-RS is set by the upper layer signaling, the T-CDM can be fixed to [1 1]. The RS density can be set to 12 REs per port in RB.

In the case of the second DMRS configuration type (DMRS configuration type 2), the front loaded DMRS can be classified according to the number of OFDM symbols allocated as follows.

The number of OFDM symbols to which the second DMRS configuration type (DMRS configuration type 2) and the front loaded DMRS are allocated = 1

Up to six ports (e.g., P0 to P5) may be multiplexed based on the length-2 F-CDM and FDM method. The RS density can be set to 4 REs per port in the RB (Resource Block).

The number of OFDM symbols to which the second DMRS configuration type (DMRS configuration type 2) and the front loaded DMRS are allocated = 2

Up to twelve ports (e.g., P0 to P11) may be multiplexed based on length-2 F-CDM, length-2 T-CDM and FDM methods. Here, when the existence of the PT-RS is set by the upper layer signaling, the T-CDM can be fixed to [1 1]. The RS density can be set to 8 REs per port in RB.

FIG. 9 is a diagram simply showing an example of a front loaded DMRS of the first DM 0RS setting type applicable to the present invention.

More specifically, in FIG. 9 (a), DMRS denotes a structure with a front loaded DMRS with one symbol, and FIG. 9 (b) shows a structure in which the DMRS is preceded by two symbols DMRS with two symbols.

In Fig. 9,? Represents the DMRS offset value in the frequency axis. At this time, the DMRS ports having the same DELTA can be mutually divided into a code division multiplexing in the frequency domain (CDM-F) or a time division multiplexing in the time domain (CDM-T) . Also, DMRS ports with different delta can be CDM-F to each other.

The terminal can acquire the DMRS port setting information set by the base station through the DCI.

1.7. DMRS 포트 그룹 (DMRS port group)1.7. DMRS port group

In the present invention, the DMRS port group may mean a set of DMRSs that are in a quasi co-located (QCL) or partial QCL (quasi co-located) relationship with each other. Here, the QCL relationship refers to a case where the long-term channel parameters such as Doppler spread and / or Doppler shift, average delay, and delay spread are the same , And a partial QCL relationship may mean that only some of the long-term channel parameters may be assumed to be the same.

FIG. 10 is a diagram simply showing an operation of a terminal transmitting and receiving signals to and from one base station as two groups of DMRS ports.

As shown in FIG. 10, the terminal may include two panels. At this time, one base station (e.g., TRP (Transmission Reception Point), etc.) may be connected to the terminal through two beams. At this time, each beam may correspond to one DMRS port group. This is because the DMRS ports defined for the different panels may not be QCLed from each other in terms of Doppler spread and / or Doppler shift.

Alternatively, in another embodiment, the plurality of panels of the terminal may form one DMRS port group.

In this case, when DCI is defined for each DMRS port group, the UE can transmit different CWs (Codewords) for each DMRS port group. In this case, one DMRS port group can transmit one or two CWs. More specifically, if the number of corresponding layers is 4 or less, one DMRS port group can transmit one CW, and if the number of corresponding layers is 5 or more, one DMRS port group can transmit two CWs. Also, different DMRS port groups may have different scheduled BWs.

Alternatively, if one DCI is defined for every DMRS port group participating in a UL transmission, all DMRS port groups may transmit one or two CWs. For example, if the total number of layers transmitted in two DMRS port groups is 4 or less, one CW is transmitted. If the total number of layers is 5 or more, two CWs can be transmitted.

In the present invention, the number of UL DMRS port groups can be set to the UE through SRS Resource Indication (SRI). For example, when the SRI sets two beams to the UE, the UE and the BS can consider that two DMRS port groups are set for the UE. According to an embodiment of the present invention, the above configuration can be applied only to a codebook-based UL transmission.

Alternatively, in the present invention, the number of UL DMRS port groups may be set to the UE through the number of SRS resource sets. For example, when a plurality of SRIs belonging to two different SRS resource sets are set in the UE, the UE and the BS can consider that two DMRS port groups are set for the UE. According to an example of the present invention, the above configuration can be applied only to the case of non-codebook based UL transmission.

1.8. DCI format in NR system1.8. DCI format in NR system

In the NR system to which the present invention is applicable, the following DCI formats can be supported. First, the NR system supports DCI format 0_0 and DCI format 0_1 in the DCI format for PUSCH scheduling, and DCI format 1_0 and DCI format 1_1 in the DCI format for PDSCH scheduling. In addition, as a DCI format that can be used for other purposes, the NR system can additionally support DCI format 2_0, DCI format 2_1, DCI format 2_2, and DCI format 2_3.

DCI format 0_0 is used for scheduling TB (Transmission Block) based (or TB-level) PUSCH, DCI format 0_1 is used for TB (Transmission Block) (Or CBG-level) PUSCH if the base signal transmission / reception is set up.

DCI format 1_0 is used for scheduling TB-based (or TB-level) PDSCH, and DCI format 1_1 is used for TB-based (or TB-level) PDSCH or CBG- based (or CBG- level PDSCH. < / RTI >

Also, the DCI format 2 _ 0 is used for notifying the slot format, and the DCI format 2 _ 1 is used for notifying the PRB and the OFDM symbol that a specific UE assumes that there is no intended signal transmission ( the DCI format 2_2 is used for transmission of the TPC (Transmission Power Control) command of the PUCCH and the PUSCH, and the DCI format 2_2 is used for transmission of the TPC (Transmission Power Control) command of the PUCCH and the PUSCH , The DCI format 2_3 may be used for the transmission of a TPC command group for SRS transmission by one or more UEs (used for the transmission of a group of TPC commands for SRS transmissions by one or more UEs).

Specific features of the DCI format can be supported by the 3GPP TS 38.212 document. That is, self-describing steps or parts not described in the DCI format related features may be described with reference to the document. In addition, all terms disclosed in this document may be described by the standard document.

1.9. 전송 스킴 (Transmission schemes)1.9. Transmission schemes

In the NR system to which the present invention is applicable, the following two transmission schemes are supported for PUSCH: codebook based transmission and non-codebook based transmission.

In an embodiment in which the present invention is applicable, if txConfig in the upper layer parameter PUSCH-Config transmitted via higher layer signaling (e.g., RRC signaling) is set to 'codebook', codebook-based transmission may be established for the UE. Alternatively, the rain for the UE, if the higher layer parameters PUSCH-Config within txConfig is set to 'noncodebook' - can be codebook-based transmission setting. If the upper layer parameter txConfig is not set, the PUSH transmission triggered by a particular DCI format (e.g., DCI format 0_0 as defined in 3GPP TS 38.211) may be based on one PUSCH antenna port.

In the following description, the rank represents the same meaning as the number of layers. For convenience of explanation, the related technical features will be collectively referred to as the " number of layers " in the following description.

1.9.1. Codebook based UL transmission

When the UE performs coherent transmission through different panels, the beamforming accuracy may be impaired by phase noise. Thus, preferably, in the presence of phase noise, the UE may perform non-coherent transmission through different panels.

Before describing the coherent transmission and the non-coherent transmission in detail in the present invention, a basic signal operation configuration will be described as follows.

At this time, as described above, the row (horizontal) direction of each precoding matrix corresponds to a specific (physical) antenna, and the column (vertical) of each precoding matrix can correspond to a specific layer.

At this time, every antenna can be mapped to a radio frequency (RF) chain by 1: 1 for each antenna. At this time, the RF chain may refer to a processing block in which a single digital signal is converted into an analog signal.

Here, coherent transmission may refer to an operation in which each layer (or data of each layer) transmits through all antennas based on a codebook.

More specifically, when transmitting a signal based on a full-coherent precoding matrix, a signal transmitted through each antenna may be generated in a baseband as follows.

For example, for the first antenna, 1/4 (X ₁ + X ₂ + X ₃ + X ₄ ) signals are generated and for the second antenna, 1/4 (X ₁ - X ₂ + X ₃ - X ₄ ) may be generated.

On the other hand, non-coherent transmission may mean an operation in which each layer (or data of each layer) transmits through a specific one of the antennas corresponding to the layer.

More specifically, when transmitting a signal based on a non-coherent precoding matrix, a signal transmitted through each antenna may be generated in a baseband as follows.

Here, the reason why the signal is generated in the baseband as described above is as follows.

In the above-described antenna-RF chain configuration, the RF chain connected to each antenna is a combination of several RF devices, each of which can generate inherent distortion (eg, phase shifting, amplitude attenuation).

Therefore, there is no problem if the distortion is small, but if it is large, beamforming may be affected.

For example, in the following equation, a specific matrix (Corrupted Codebook) is added to express the contamination of the transmission signal through the RF chain. At this time, if there is no distortion, the matrix becomes the identity matrix.

In the above equation, the data X ₁ should be transmitted in the vector direction [1 1 jj], but due to the distortion generated by the RF chain

Direction. Therefore, the larger the value of? ₁ ? ₂ ,? ₃ ,? ₄ , the greater the signal transmission direction can be largely different from the originally desired direction.

At this time, even if the distortion generated by the four RF chains is large, it may not be a problem if the distortion magnitudes are all the same. because,

This is because the beam direction does not change irrespective of the magnitude of? 1.

Therefore, when the distortion of the RF chain is large, a non-coherent transmission scheme that does not perform beamforming may be preferable as in Equation (6).

From the data X ₁ perspective, the codebook contaminated with distortion and the codebook not so distorted are simply e ^{jθ 1} _, e ^{jθ 2} _, e ^{jθ 3} _{, and} e ^{jθ 4} . As a result, this distortion can be corrected in the channel estimation.

Therefore, if the distortion of the RF chain is not large or the distortions caused by all RF chains are the same, it may be desirable to transmit the signal using a full-coherent codebook capable of digital beamforming. Alternatively, it may be desirable to transmit a signal using a non-coherent codebook where digital beamforming is not possible if the distortions are different for each RF chain and their size is large enough to affect beamforming.

In addition, for partial coherent codebook with rank 4 (or partial coherent codebook for four layers), the RF chain characteristics connected to

antennas

1 and 3 are similar, so that the distortion they produce is the same . This relationship can be similarly applied to antennas # 2 and # 4.

Thus, for a partial coherent codebook with rank 4 (or a partial coherent codebook for four layers) (eg,

TPMI index

1 or 2 in Table 14), the transmitter (eg, 2 antennas & 4 antennas), it is possible to transmit signals in a coherent transmission scheme, but in a non-coherent manner between

antennas

1 and 2. These characteristics can be confirmed through TPMI indices 4 to 11 in Table 10, TPMI indices 6 to 13 in Table 12, and TPMI indices 1 to 2 in Table 13.

On the other hand, if the Modulation and Coding Scheme (MCS) is low, the effect of phase noise may not be significant (ie, it may be marginal). Thus, the impairment to the beamforming accuracy may also be small (i. E., Marginal). In such a case, preferably, the UE may perform coherent combining.

On the other hand, the influence due to the phase noise is relatively dependent on the RF (Radio Frequency), and in the case of an expensive RF element, the phase noise may be very small.

Therefore, the NR system applicable to the present invention can support both non-coherent / coherent transmission.

For codebook-based transmission, the UE determines a codebook subset based on the reception of a Transmitted Precoding Matrix Indicator (TPMI) and a codebookSubset in an upper layer signaling PUSCH-Config . Here, the codebookSubset may be set to one of 'fullAndPartialAndNonCoherent', 'partialAndNonCoherent', and 'nonCoherent' depending on the UE capability indicating the UE capable of supporting the codebook. Here, 'fullAndPartialAndNonCoherent' means that the UE can support both a full coherent codebook, a partial coherent codebook, and a non-coherent codebook, and 'partialAndNonCoherent' coherent codebook and non-coherent codebook, and 'nonCoherent' may mean that the UE can only support non-coherent codebook.

Here, the maximum transmission rank (or the number of layers) applied to the codebook may be set by maxRank in the upper layer parameter PUSCH-Config .

At this time, the UE reporting the 'partialAndNonCoherent' transmission as its UE capability does not expect the codebook subset to be set to 'fullAndPartialAndNonCoherent'. Because reporting the 'partialAndNonCoherent' transmission as UE capability means that the UE does not support signaling based on a full coherent codebook, as described above, It may not expect a setting for signal transmission based on a coherent codebook (i.e., a codebook subset set to 'fullAndPartialAndNonCoherent').

Similarly, the UE reporting its 'nonCoherent' transmission with its UE capability does not expect the codebook Subset to be set to 'fullAndPartialAndNonCoherent' or 'partialAndNonCoherent'.

In the NR system to which the present invention is applicable, two options are supported for UL waveforms: one is CP-OFDM (Cyclic Prefix-Orthogonal Frequency Division Multiplexing) and the other is DFT-s-OFDM (Discrete Fourier Transform- Orthogonal Frequency Division Multiplexing). At this time, it is necessary to apply transform precoding in order to generate the DFT-s-OFDM waveform.

Therefore, when the UE does not perform the conversion precoding for the UE according to the present invention, the UE uses the CP-OFDM waveform as the uplink waveform. On the other hand, if the transform precoding is enabled for the UE or if the UE can apply transform precoding, the UE uses the DFT-s-OFDM waveform as the uplink waveform.

In the following description, it is collectively referred to as a case where the transform precoding is disabled for a specific UE or the transformed precoding is disabled when the specific UE is unable to apply the transform precoding.

At this time, the precoder W determined for the codebook-based transmission may be determined according to the following table based on the coefficients of the transport layer, the number of antenna ports, and the TPMI included in the DCI scheduling UL transmission.

Table 9 shows a precoding matrix W for single layer transmission using two antenna ports and Table 10 shows a precoding matrix W for single layer transmission using four antenna ports with transform precoding disabled .

Table 11 shows a precoding matrix W for two-layer transmission using two antenna ports with transform precoding disabled, and Table 12 shows four precoding matrices W with four antenna ports with transform precoding disabled Table 13 shows a precoding matrix W for three-layer transmission using four antenna ports with transform precoding disabled, and Table 14 shows a precoding matrix W for three-layer transmission using transform And a precoding matrix W for four-layer transmission using four antenna ports with precoding disabled (with transform precoding disabled).

1.9.2. Non-codebook based UL transmission

For non-codebook based transmission, if multiple SRS resources are configured, the UE may determine the PUSCH precoder and the transmission rank (or the number of layers) based on (wideband) SRI (sounding reference signal resource indicator). Here, the SRI may be provided through DCI or higher layer signaling.

Here, the determined precoder may be an identity matrix.

2. 제안하는 실시예2. Proposed embodiment

Hereinafter, the present invention will be described in more detail based on the above technical ideas.

In the present invention, a configuration in which a PT-RS is transmitted and received in a CDM (Code Division Multiplexing) manner on a frequency axis and a PT-RS transmitting and receiving method of the transmitting apparatus and the receiving apparatus for the same will be described in detail. In the following description, the configuration in which the PT-RS is CDM-transmitted / received is referred to as Localized PT-RS for convenience. Also, the configuration in which the PT-RS is transmitted and received without being CDM is referred to as a distributed PT-RS for the sake of convenience.

Accordingly, a Localized PT-RS is mapped to at least two subcarriers to which a corresponding (or associated) DMRS port per resource block (RB) is mapped, and the Distributed PT- Is mapped only to one subcarrier to which a corresponding (or associated with) DMRS port per RB is mapped.

Therefore, the localized PT-RS frequency axis position in the RB can be determined based on the DMRS port position associated with the corresponding PT-RS. Alternatively, the Localized PT-RS frequency axis position in the RB may be determined based on the CDM group including the DMRS port associated with the PT-RS.

FIG. 10 shows an example of a localized PT-RS according to an exemplary embodiment of the present invention.

In FIG. 10, it is assumed that PT-RS ports # 0 and # 1 are associated with DMRS ports # 0 and # 1. At this time, as shown in FIG. 10, the PT-RS port may be mapped to some frequency resources (for example, two sub-carrier resources) to which the associated DMRS port is mapped. In the following description, as shown in FIG. 10, a configuration in which two PT-RS ports are associated with one CDM is referred to as a first type (or Type A) localized PT-RS.

11 is a diagram illustrating an example of Localized PT-RS according to another example of the present invention.

In the case of FIG. 11, unlike FIG. 10, four PT-RS ports are bundled into one CDM (or associated with one CDM). In the following description, a configuration in which four PT-RS ports (or more than two PT-RS ports) are associated with one CDM is referred to as a second type (or Type B) localized PT- RS.

In the following description, a localized PT-RS may mean any type of localized PT-RS described above, unless otherwise specified.

In the present invention, a plurality of Localized PT-RSs can be set for the base station or the terminal. For example, when a plurality of localized PT-RSs are set for a base station, the plurality of localized PT-RSs may be set for each of a plurality of terminals that transmit and receive signals to or from the base station, or may be set for a specific terminal. At this time, the location (in the RB) to which the plurality of localized PT-RSs are mapped can be set / determined the same for all RBs including the PT-RS.

12 is a diagram illustrating an example of a Localized PT-RS according to another example of the present invention. As shown in FIG. 12, localized PT-RSs in RBs # 1 and # 3 may be mapped on the same frequency position (or subcarrier index).

In the present invention, the RB position (i.e., the RB to which the PT-RS is mapped) or the position in the RB (i.e., the sub-carrier to which the PT-RS in the specific RB is mapped) of the Localized PT- / RTI > can be determined / set on the basis of

More specifically, the localized PT-RSs set in the same cell can be set / defined orthogonally for each UE. On the other hand, localized PT-RSs between different cells can cause collisions. Thus, when determining the frequency position of the localized PT-RS based on the cell ID or the virtual cell ID, such collision can be minimized.

In addition, the frequency location of the localized PT-RS can be defined / set for each BWP (Bandwidth Part).

The time density of the localized PT-RS according to the present invention can be set / applied similarly to the distributed PT-RS. That is, as shown in Table 5 and Fig. 7 and the like, the localized PT-RS can be determined based on the scheduled MCS.

Alternatively, localized PT-RS time densities can be indicated via higher layer signaling (eg RRC, MAC-CE). For example, if two different TRPs serve one terminal, the TRPs may each drop an independent DCI to the terminal. At this time, different PDSCHs scheduled by the two DCIs are transmitted to the same resource, and a unique PT-RS can be transmitted for each PDSCH. If the UE misses one of the two DCIs, the UE can not know the indicated MCS from the missing DCI and consequently can not know the PT-RS time density. Therefore, in this case, the PT-RS time density according to the MCS may be inappropriate. To solve this problem, fix the time density to a specific value (eg 1 or 2) with a specific value through higher layer signaling (eg RRC, MAC-CE). In this case, ambiguity to the PT-RS time density disappears even if a specific DCI is missing.

The frequency density of the localized PT-RS according to the present invention can be set / applied similarly to the distributed PT-RS. That is, as shown in Table 7 and the like, the localized PT-RS can be set / defined as 1 / Q based on the scheduled bandwidth. In this case, 1 / Q may mean that one localized PT-RS is set / defined per Q RB.

In the present invention, in case of a first type (or Type A) localized PT-RS port, a transmitting apparatus (e.g., a base station or a terminal) transmits a power boosting level based on the number of FDM (Frequency Division Multiplexed) To the PT-RS. Here, the DL / UL power boosting refers to transmission power of one layer (belonging to PDSCH / PUSCH) transmitted using a DMRS port having a relation with a PT-RS port by a transmitting apparatus Means increasing the transmission power of one DL / UL PT-RS port group. That is, the DL / UL PT-RS power boosting level is set to a value that indicates that the transmission power of one DL / UL PT-RS port group is transmitted (belonging to the PDSCH / PUSCH) using a DMRS port associated with the PT- It can indicate how high the transmission power of one layer is.

13 is a diagram illustrating an example of a Localized PT-RS according to another example of the present invention.

It is assumed in FIG. 13 that PT-RS ports # 0 and # 1 constitute a localized PT-RS group # 0 and PT-RS ports # 2 and # 3 constitute a localized PT-RS group # 1. At this time, since the localized PT-RS groups # 0 and # 1 are orthogonal to each other, the transmitting apparatuses transmitting the corresponding PT-RS through the localized PT-RS group # 0 (or localized PT-RS group # 1) The PT-RS can be transmitted by boosting the power by 3 dB. However, the power boosting operation can be applied only when two (localized) PT-RS groups are defined as shown in FIG. In other words, PT-RS group # 0 (or PT-RS group # 1) is set for a specific transmitting apparatus and PT-RS group # 1 (or PT- 0) is not set, the total number of PT-RS groups set is 1, and the transmitting apparatus can transmit the PT-RS set (or scheduled) without power boosting.

In case of the DMRS port setting type 2, unlike FIG. 13, three PT-RS port groups can be set / defined. In this case, the transmitting apparatus (e.g., the base station or the terminal) can perform power boosting by 4.77 dB through each PT-RS port group to transmit the corresponding PT-RS. However, the power boosting operation can be applied only when three localized PT-RS groups are defined. In other words, when only two (or one) PT-RS port group among three PT-RS port groups are set based on the DMRS port setting type 2, the transmitting apparatus transmits 3 dB (or 0 dB ) To the power-boosted PT-RS.

In this case, the power boosting level described above may mean a maximum power boosting level through power borrowing from another PT-RS port group.

In this case, the power boosting level and / or the power boosting level may be separately signaled (e.g., higher layer signaling (e.g., Radio Resource Control (RRC), Medium Access Control- Downlink Control Information).

Meanwhile, the terminal can indirectly determine whether the DL / UL PT-RS power is boosted and / or the power boosting level through signaling related to the DMRS port. In the following description, a description will be made in detail of a technique configuration applicable to the present invention based on the DMRS setting type 1.

For example, if the UE recognizes that the number of CDM groups is one through the DMRS port information indicated to the UE, the UE only activates one localized PT-RS port group and deactivates another localized PT-RS port group Can be assumed. In this case, the terminal does not apply (or assume that it does not apply) power boosting to PT-RS port group # 0.

In another example, if the UE recognizes that the number of CDM groups is two through the DMRS port information indicated to the UE and the DMRS ports assigned to the UE belong to a specific CDM group (e.g., DMRS ports # 0 and # 1) , The terminal may also assume that a localized PT-RS port group other than the localized PT-RS port group connected to the allocated DMRS port is also activated. In other words, the terminal may assume that a localized PT-RS port group other than the localized PT-RS port group connected to the DMRS port allocated to the terminal is allocated to another terminal. In this case, the terminal can apply (or assume applicable) 3 dB power boosting to the assigned PT-RS port group.

As another example, when the UE recognizes that the number of CDM groups is two through the DMRS port information indicated to the UE, the DMRS ports allocated to the UE belong to different CDM groups (e.g., DMRS ports # 0 and # 2) If the QCL sources of the DMRS ports are all the same, it is assumed that only the localized PT-RS port group connected to the allocated DMRS port is activated. In this case, the terminal does not apply (or assume that it does not apply) 3 dB power boosting to PT-RS port group # 0.

As another example, when the UE recognizes that the number of CDM groups is two through the DMRS port information indicated to the UE, the DMRS ports allocated to the UE belong to different CDM groups (e.g., DMRS ports # 0 and # 2) If the QCL sources of the DMRS ports are not all the same, the UE may assume that only all localized PT-RS port groups are activated. In this case, the terminal can apply (or assume applicable) 3 dB power boosting for PT-RS port group # 0 / # 1.

The above-described technical constructions can be similarly applied to the distributed PT-RS.

In the present invention, a terminal can be configured with a specific type of DL / UL PT-RS via higher layer signaling or DCI received from a base station. More specifically, the terminal receives either one of a first type (or type A) localized PT-RS, a second type (or type B) localized PT-RS, and a distributed PT-RS via higher layer signaling or DCI received from the base station Can be set.

Alternatively, the terminal may establish one of a localized PT-RS or a distributed PT-RS via higher layer signaling or DCI from the base station and additionally transmit the higher layer signaling or DCI from the base station (when a localized PT- 1 type (or type A) localized PT-RS or a second type (or type B) localized PT-RS.

In the present invention, the OCC (Orthogonal Cover Code) applied to Localized PT-RS can be determined by the DMRS port index.

More specifically, one localized PT-RS may comprise a plurality of PT-RS ports that are CDMs. In this case, the base station needs to inform the terminal which OCC is used.

Meanwhile, the DMRS port index can be allocated exclusively to the UE. Therefore, when mapping between the DMRS port index and the OCC, the OCCs set / assigned to the UEs may be different from each other.

At this time, the association (or mapping relationship) between the DMRS port index and the OCC can be set by upper layer signaling (eg, RRC, MAC-CE) or DCI. For example, the association between the DMRS port index and OCC can be established as shown in the following table.

DMRS port indexDMRS port index	PT-RS port indexPT-RS port index	OCCOCC

#0#0	#0#0	[ 1 1 ][1 1]
#1#One	#1#One	[ 1 -1 ][1 -1]
#2#2	#2#2	[ 1 1 ][1 1]
#3# 3	#3# 3	[ 1 -1 ][1 -1]

In addition, the frequency position in the RB of the localized PT-RS port can be set by higher layer signaling or DCI. In the case of the first type (or type A) localized PT-RS, the frequency position in the RB of the PT-RS is defined in association with the PT-RS port index and / or the DMRS port index and the CDM group associated therewith . For example, when the frequency position of the PT-RS in the RB is determined in association with the DMRS port index, the base station transmits one of the subcarrier sets in the corresponding RB (e.g., {0, 2}, ..., May be set to the terminal through higher layer signaling or DCI.

DMRS port indexDMRS port index	PT-RS port indexPT-RS port index	OCCOCC	Subcarrier within RBSubcarrier within RB

#0#0	#0#0	[ 1 1 ][1 1]	{0,2}, {2,4}, {4,6}, {6,8}, {8,10}{0,2}, {2,4}, {4,6}, {6,8}, {8,10}
#1#One	#1#One	[ 1 -1 ][1 -1]	{0,2}, {2,4}, {4,6}, {6,8}, {8,10}{0,2}, {2,4}, {4,6}, {6,8}, {8,10}
#2#2	#2#2	[ 1 1 ][1 1]	{1,3}, {3,5}, {5,7}, {7,9}, {9,11}{1,3}, {3,5}, {5,7}, {7,9}, {9,11}
#3# 3	#3# 3	[ 1 -1 ][1 -1]	{1,3}, {3,5}, {5,7}, {7,9}, {9,11}{1,3}, {3,5}, {5,7}, {7,9}, {9,11}

In the present invention, a terminal uses a DMRS table index and / or a DMRS port group and / or a DL / UL PT-RS number to determine a PT-RS port group other than the PT- Rate matching (or signal transmission / reception considering the different PT-RS port group).

More specifically, the DMRS table can implicitly indicate not only one or more DMRS ports to be used by a specific terminal but also whether or not the DMRS ports not set by the specific terminal are occupied by other terminals. Accordingly, the UE can recognize the above information using the set DMRS table index. The UE determines whether rate matching (or transmission / reception of signals considering the different PT-RS port group) is performed for another PT-RS port group other than the PT-RS port group allocated to the UE based on the set DMRS table index And determine whether to power-up the PT-RS port group allocated to the UE.

If the non-established DMRS ports are occupied by other terminals, it may mean that the other terminal can transmit / receive PT-RSs. Accordingly, in order to consider (or protect) the PT-RS for the other terminal, the terminal may perform rate matching on the resource area in which the other terminal transmits / receives the PT-RS.

As a more specific example, the DMRS table applicable to the invention of the present invention can be composed of a table showing the number of CDM groups and the associated DMRS ports as shown in one of the following Tables 17 to 20. At this time, value values of the following DMRS table can be provided through DCI.

In this case, if the number of CDM groups indicated through the DMRS table is 1, the UE can determine that a DMRS port is defined only in the CDM group (e.g., CDM group # 0) allocated to the UE, For example, CDM group # 1). That is, the UE can indirectly confirm that the DMRS ports # 2 and # 3 are not used by the other UE through the DMRS table. In this case, the UE does not need to perform rate matching on resources defined / assigned to PT-RS port groups other than the PT-RS port group set for the UE. In other words, the terminal can assume that the other terminal does not use the localized PT_RS port # 1.

On the other hand, when the number of CDM groups indicated by the DMRS table is 2, the UE not only has a CDM group (e.g., CDM group # 0) allocated to the UE but also a CDM group # 1), it can be assumed that a DMRS port is defined. In other words, the terminal may assume that data is not transmitted from a CDM group (e.g., CDM group # 1) not allocated to the UE. Accordingly, the UE can indirectly confirm that the DMRS ports # 2 (and # 3) are used by another UE through the DMRS table. In this case, the terminal can perform rate matching on resources defined / allocated to a PT-RS port group other than the PT-RS port group set for the terminal. In other words, the terminal can assume that the other terminal uses the localized PT_RS port # 1.

For example, in FIG. 13, if it is determined that a specific terminal has been allocated DMRS ports # 0 and # 1 and that DMRS ports # 2 and / or # 3 are occupied by other terminals (through a DMRS table) Can perform rate matching on the defined resource of PT-RS port group # 1.

On the other hand, when the specific terminal has been allocated the

DMRS ports #

0, 1, 2, 3 and the DMRS ports constitute one DMRS port group (for example, the DMRS ports have the same QCL source, port group), or if the number of DL / UL PT-RS ports is one, the specific terminal may not perform rate matching on a resource defined by the PT-RS port group # 1. This is because resources defined in other PT-RS port group # 1 are not used by other terminals. On the other hand, when the DMRS ports constitute two DMRS port groups (for example, DMRS ports # 0 and # 1 have the same QCL source and DMRS ports # 2 and # 3 have the same QCL source, # 0 and # 2 have different QCL sources. Therefore, when DMRS ports # 0 and # 2 are set to the UE, two DMRS port groups can be defined), (localized) PT-RS group # 0 / # 1 can be activated, so that the specific terminal can perform rate matching on the resource defined by the PT-RS port group # 1.

The operation of the terminal based on the DMRS table described above can be similarly applied not only to the localized PT-RS but also to the distributed PT-RS.

14, if the terminal has been allocated DMRS ports # 0 and # 1 and recognizes that the DMRS ports # 2 and / or # 3 are occupied by other terminals (via the DMRS table) port # 2, and port # 3 may perform rate matching on the defined resource.

In the above-described configuration, the rate matching of the terminal can be set by the upper layer signaling of the base station. If the rate matching of the terminal is set to 'OFF' by the base station, the terminal does not always perform rate matching with respect to resources defined in another PT-RS port group, unlike the above-described operation. On the other hand, when the rate matching of the terminal is set to 'ON' by the base station, the terminal determines whether the other PT-RS port group is used by the other terminal as in the above- group can selectively perform rate matching for the defined resource.

소결Sintering

A terminal according to the present invention receives information on a demodulation reference signal (DMRS) port index allocated to the terminal (or related to the terminal) from the base station (S1510, S1610). In response to this, the base station transmits information on the DMRS port index allocated to one or more terminals (or related to one or more terminals) to each terminal (S1510, S1710). Hereinafter, for convenience of description, features of the present invention will be described in detail based on operations of transmitting and receiving signals between one terminal and one base station.

As a further embodiment applicable to the present invention, the terminal may receive information on the number of DMRS code division multiplexing (CDM) groups associated with the terminal from the base station (S1520, S1620). In response, the base station may transmit information on the number of associated DMRS CDM groups for each of at least one terminal (S1520, S1720). Then, the terminal can confirm / determine various information for receiving the downlink signal based on the information received through S1510 (or S1610) or the information received through S1510 (or S1610) and S1520 (or S1620). For example, the UE may determine, based on the information, a resource region in which the PT-RS is received, an Orthogonal Cover Code (OCC) for the PT-RS, a power boosting level of the PT- Whether or not the PT-RS is transmitted to another terminal, and the like. The operation will be described in detail below.

A terminal according to the present invention receives the downlink signal including a phase tracking reference signal (PT-RS) transmitted through a plurality of sub-carriers for a DMRS port index allocated to the terminal (S1540, S1640 ). In response to this, the base station transmits the downlink signal including the at least one terminal-specific PT-RS to the one or more terminals (S1540 and S1740).

In the present invention, the terminal receives the PT-RS based on the OCC for the PT-RS. At this time, the OCC can be determined based on the DMRS port index allocated to the UE.

As described above, the UE can receive the PT-RS through one resource block for two or four consecutive resource blocks. In general, the UE can receive a PT-RS through a plurality of second resource blocks spaced at a predetermined interval from among a plurality of consecutive first resource blocks.

At this time, a resource block in which the PT-RS is transmitted for each of the two (or four) consecutive resource blocks of the second resource blocks among the plurality of consecutive first resource blocks, May be determined based on at least one of a physical cell identifier, a virtual cell identifier, or information indicated by upper layer signaling set to the terminal.

At this time, the position of a plurality of sub-carriers in which the PT-RS is received in one of the second resource blocks may be determined based on a demodulation reference signal port index allocated to the UE from the BS.

Alternatively, the location of a plurality of sub-carriers in which the PT-RS is received in one of the second resource blocks may be determined based on a demodulation reference signal port index allocated to the UE from the BS, a physical cell identifier, Terminal identifiers, or information indicated by higher layer signaling.

As described above, the UE according to the present invention determines whether there is a PT-RS transmitted to another UE based on at least one of the number of DMRS CDM groups associated with the UE and the DMRS port index allocated to the UE, RS of the transmitted PT-RS, and receive the downlink signal including the PT-RS based on the determination.

For example, the MS receiving the information indicating that the number of the DMRS CDM group is 1 from the BS can receive the downlink signal on the assumption that there is no PT-RS transmitted from the BS to another MS. More specifically, assuming that there is no PT-RS transmitted from the BS to another MS, the MS receiving the downlink signal transmits data in the resource area for the PT-RS of the DMRS CDM group not associated with the MS It is possible to receive the downlink signal.

At this time, upon receiving the information indicating that the number of the DMRS CDM group is 1 from the BS, the terminal determines whether the PT-RS is in a state of being connected to the DMRS CDM group RS, the PT-RS, and the PT-RS. Herein, one or more PT-RS ports associated with a DMRS CDM group not associated with the MS may include a DMRS CDM group including a DMRS port having a PT-RS assigned to the MS, And may be one or more PT-RS ports associated with DMRS ports included in different DMRS CDM groups. Here, the association (or connection relationship) may mean that the frequency location for the corresponding PT-RS port and the precoding matrix are determined by the frequency position and the precoding matrix for the associated DMRS port.

As another example, when receiving information indicating that a plurality of DMRS CDM groups are received from the BS and all the DMRS port indices allocated to the MS are included in one CDM group, the MS transmits PT-RS The downlink signal can be received. More specifically, the terminal receiving the downlink signal on the assumption that there is a PT-RS transmitted from the base station to another terminal transmits one or more PT-RSs having an association with one or more DMRS CDM groups not associated with the terminal, It is possible to receive the downlink signal on the assumption that data is not transmitted in the resource region for RS.

As another example, if it is determined that all the DMRS port indices allocated to the UE are included in different DMRS CDM groups and the QCLs of the DMRS ports included in the different DMRS CDM groups are received, (Qausi-co-Located) sources are all the same, there is no PT-RS transmitted from the base station to another terminal, and the number of PT-RS ports assigned to the terminal is one, Lt; / RTI > More specifically, in the above case, the MS may receive the downlink signal on the assumption that data is transmitted in a resource region for a PT-RS associated with one or more DMRS CDM groups not associated with the MS.

In addition, when receiving information indicating that a plurality of DMRS CDM group numbers are received from the base station, the DMRS port index allocated to the UE is included in different DMRS CDM groups, and the QCL sources of the DMRS ports included in the different DMRS CDM groups are all The same terminal can receive the downlink signal including the PT-RS on the assumption that the PT-RS is transmitted without power boosting based on one or more PT-RS ports associated with another DMRS CDM group.

As another example, when receiving information indicating that the number of DMRS CDM groups is plural, the DMRS port index assigned to the UE is included in a different DMRS CDM group and the QCL source of the DMRS ports included in the different DMRS CDM group The UE can receive the downlink signal on the assumption that there is no PT-RS transmitted from the BS to another UE.

Receiving a plurality of DMRS CDM group numbers from the BS, receiving a plurality of DMRS CDM groups from the BS, assigning the DMRS port indexes to the DMRS CDM groups different from each other, and transmitting the QCL sources of the DMRS ports included in the different DMRS CDM groups, And if the total number of PT-RSs indicated from the BS is 2 or more, the MS can receive the downlink signal including the PT-RS on the assumption that the PT-RS is power-boosted and transmitted. If the total number of PT-RSs indicated from the BS is one, the MS expects the PT-RS to be transmitted without power boosting based on one or more PT-RS ports associated with another DMRS CDM group.

In the present invention, the length of the OCC may be set equal to the number of PT-RS ports sharing a resource region for the PT-RS. For example, the number of PT-RS ports sharing a resource region for the PT-RS may be the same as the number of sub-carriers for which the PT-RS is received in one resource block.

It is obvious that examples of the proposed method described above can also be included as one of the implementing methods of the present invention, and thus can be considered as a kind of proposed methods. In addition, the proposed schemes described above may be implemented independently, but may be implemented in a combination (or merging) of some of the proposed schemes. A rule may be defined such that the base station informs the terminal of the information on whether or not to apply the proposed methods (or information on the rules of the proposed methods) through a predefined signal (e.g., a physical layer signal or an upper layer signal) have.

3. 장치 구성3. Device Configuration

18 is a diagram showing a configuration of a terminal and a base station in which the proposed embodiment can be implemented. The terminal and the base station shown in FIG. 18 operate to implement the above-described embodiments of the downlink signal transmission / reception method between the terminal and the base station.

A user equipment (UE) 1 can operate as a transmitter in an uplink and as a receiver in a downlink. Also, the base station (eNB or gNB, 100) can operate as a receiving end in the uplink and as a transmitting end in the downlink.

That is, the terminal and the base station may each include a transmitter (Transmitter 10, 110) and a receiver (Receiver 20, 120) for controlling transmission and reception of information, data and /

Or antennas

30 and 130 for transmitting and receiving messages, and the like.

The terminal and the base station each include a processor (Processor) 40, 140 for performing the above-described embodiments of the present invention. The

processor

40, 140 may be configured to control the

memory

50, 150 and / or the

transmitter

10, 110 and / or the

receiver

20, 120 to implement the procedures / methods and / .

In one example, the

processor

40, 140 includes a communication modem designed to implement wireless communication technology (e.g., LTE, NR). The

memories

50 and 150 are connected to the

processors

40 and 140 and store various information related to the operation of the

processors

40 and 140. [ For example, the

memory

50, 150 may be implemented with software code (e.g., code) that includes instructions for performing some or all of the processes controlled by the

processor

40, 140 or for performing the procedures and / Can be stored.

Transmitter

10, 110 and / or

receiver

20, 120 are coupled to

processor

40, 140 and transmit and / or receive wireless signals. Here,

processors

40 and 140 and

memories

50 and 150 may be part of a processing chip (e.g., System on a Chip, SoC).

The terminal 1 or the communication device included in the terminal receives the information on the demodulation reference signal (DMRS) port index allocated to the terminal from the base station and transmits the allocated DMRS port index And a phase tracking reference signal (PT-RS) transmitted through a plurality of subcarriers for the downlink signal. At this time, the PT-RS is received based on an Orthogonal Cover Code (OCC), and the OCC can be determined based on the allocated DMRS port index.

Correspondingly, the base station 100 or the communication device included in the base station transmits information on a demodulation reference signal (DMRS) port index allocated to one or more terminals to the one or more terminals, And transmits the downlink signal including the at least one terminal's phase tracking reference signal (PT-RS) to the terminal. Here, the at least one terminal-specific PT-RS is transmitted based on an associated orthogonal cover code (OCC) through a plurality of sub-carriers for a DMRS port index allocated to the associated terminal, The associated OCC may be determined based on the DMRS port index assigned to each of the one or more terminals.

A transmitter and a receiver included in a terminal and a base station can perform a packet modulation and demodulation function for data transmission, a fast packet channel coding function, an orthogonal frequency division multiple access (OFDMA) packet scheduling, a time division duplex (TDD) Packet scheduling and / or channel multiplexing functions. In addition, the terminal and the base station of FIG. 18 may further include a low-power RF (Radio Frequency) / IF (Intermediate Frequency) unit.

In the present invention, a personal digital assistant (PDA), a cellular phone, a personal communication service (PCS) phone, a global system for mobile (GSM) phone, a wideband CDMA A handheld PC, a notebook PC, a smart phone or a multi-mode multi-band (MM) terminal may be used.

Here, the smart phone is a terminal that combines the advantages of a mobile communication terminal and a personal portable terminal, and may mean a terminal that integrates data communication functions such as calendar management, fax transmission / reception, and Internet access, have. In addition, the multimode multiband terminal can operate both in a portable Internet system and other mobile communication systems (for example, Code Division Multiple Access (CDMA) 2000 system, WCDMA (Wideband CDMA) system, etc.) .

Embodiments of the present invention may be implemented by various means. For example, embodiments of the present invention may be implemented by hardware, firmware, software, or a combination thereof.

For a hardware implementation, the method according to embodiments of the present invention may be implemented in one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs) Field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, and the like.

In the case of an implementation by firmware or software, the method according to embodiments of the present invention may be implemented in the form of a module, a procedure, or a function for performing the functions or operations described above. For example, the software code may be stored in the

memory units

50, 150 and driven by the

processor

40, 140. The memory unit may be located inside or outside the processor, and may exchange data with the processor by various means already known.

The present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. Accordingly, the above description should not be construed in a limiting sense in all respects and should be considered illustrative. The scope of the present invention should be determined by rational interpretation of the appended claims, and all changes within the scope of equivalents of the present invention are included in the scope of the present invention. In addition, claims that do not have an explicit citation in the claims may be combined to form an embodiment or be included in a new claim by amendment after the filing.

Embodiments of the present invention can be applied to various radio access systems. Examples of various wireless access systems include 3GPP (3rd Generation Partnership Project) or 3GPP2 system. The embodiments of the present invention can be applied not only to the various wireless access systems described above, but also to all technical fields applying the various wireless access systems. Furthermore, the proposed method can be applied to a mmWave communication system using a very high frequency band.

Claims

A method for a terminal to receive a downlink signal in a wireless communication system,

Receiving information on a demodulation reference signal (DMRS) port index allocated to the UE from the BS; And

And receiving the downlink signal including a phase tracking reference signal (PT-RS) transmitted through a plurality of sub-carriers for the allocated DMRS port index,

The PT-RS is received based on an Orthogonal Cover Code (OCC)

Wherein the OCC is determined based on the allocated DMRS port index.
The method according to claim 1,

Wherein the PT-RS is received through a plurality of second resource blocks spaced apart from each other by a predetermined interval among a plurality of consecutive first resource blocks.
3. The method of claim 2,

Wherein the location of the second resource block among the plurality of consecutive first resource blocks is determined based on at least one of a physical cell identifier, a virtual cell identifier, or information indicated by upper layer signaling, Signal receiving method.
3. The method of claim 2,

Wherein a position of a plurality of sub-carriers for receiving the PT-RS in one of the second resource blocks is determined based on a demodulation reference signal port index allocated to the UE from the BS.
3. The method of claim 2,

The location of a plurality of sub-carriers in which the PT-RS is received in one of the second resource blocks is determined by a demodulation reference signal port index allocated to the UE from the BS, together with a physical cell identifier, a virtual cell identifier, Or information indicated by higher layer signaling. &Lt; Desc / Clms Page number 13 >
The method according to claim 1,

Further comprising: receiving information on the number of Code Division Multiplexing (CDMA) groupings from the base station;

The MS determines whether there is a PT-RS transmitted to another MS based on at least one of the number of the DMRS CDM groups and the DMRS port index assigned to the MS, and whether the PT-RS transmitted to the MS is power-boosted And receiving the downlink signal including the PT-RS based on the determination.
The method according to claim 6,

Receiving the information indicating that the number of the DMRS CDM group is 1 from the BS, the UE receives the downlink signal on the assumption that there is no PT-RS transmitted from the BS to another UE.
8. The method of claim 7,

Assuming that there is no PT-RS transmitted from the BS to another MS, the MS receiving the downlink signal assumes that data is transmitted in the resource region for the PT-RS of the DMRS CDM group not associated with the MS And receiving the downlink signal.
The method according to claim 6,

Upon receiving the information indicating that the number of the DMRS CDM groups is 1 from the BS,

Receiving the downlink signal including the PT-RS on the assumption that the PT-RS is transmitted without power boosting based on one or more PT-RS ports associated with a DMRS CDM group not associated with the terminal, Link signal receiving method.
The method according to claim 6,

The method comprising: receiving, from the BS, information indicating that the number of DMRS CDM groups is plural, and including all the DMRS port indexes allocated to the MS in one CDM group,

And receiving the downlink signal on the assumption that there is a PT-RS transmitted from the base station to another terminal.
11. The method of claim 10,

The terminal receiving the downlink signal on the assumption that there is a PT-RS transmitted from the base station to another terminal,

And receiving the downlink signal on the assumption that data is not transmitted in a resource region for at least one PT-RS having an association with at least one DMRS CDM group not associated with the UE.
The method according to claim 6,

Wherein the UE receives information indicating that the number of DMRS CDM groups is N from the BS and includes all the DMRS port indexes allocated to the UE in one DMRS CDM group,

The downlink signal including the PT-RS is received on the assumption that the power boosting level of the PT-RS based on one or more PT-RS ports having an association with another DMRS CDM group is 10 * log 10 N (dB) Wherein the downlink signal is received by the base station.
The method according to claim 6,

The method comprising: receiving information indicating that a plurality of DMRS CDM group numbers are received from the base station, assigning a DMRS port index to the UEs in different DMRS CDM groups, and performing QCL (Qausi-co- Located sources are all the same,

And receiving the downlink signal on the assumption that there is no PT-RS transmitted from the base station to another terminal and that the number of PT-RS ports allocated to the terminal is one.
The method according to claim 6,

The method comprising: receiving information indicating that a plurality of DMRS CDM group numbers are received from the base station, assigning a DMRS port index to the UEs in different DMRS CDM groups, and performing QCL (Qausi-co- Located sources are all the same,

Receiving the downlink signal including the PT-RS on the assumption that the PT-RS is transmitted without power boosting based on one or more PT-RS ports associated with another DMRS CDM group.
The method according to claim 6,

The method comprising: receiving information indicating that a plurality of DMRS CDM group numbers are received from the base station, assigning a DMRS port index to the UEs in different DMRS CDM groups, and performing QCL (Qausi-co- The terminal having a different source,

Wherein the downlink signal is received under the assumption that there is no PT-RS transmitted from the base station to another terminal.
The method according to claim 6,

Wherein the terminal receives information indicating that the number of DMRS CDM groups is plural from the base station, the DMRS port index allocated to the terminal is included in different DMRS CDM groups, and the QCLs of the DMRS ports included in the different DMRS CDM group (Qausi-co-Located) source is different and the total number of PT-RSs indicated from the base station is 2 or more,

The UE receives the downlink signal including the PT-RS on the assumption that the PT-RS is transmitted with power boosting based on one or more PT-RS ports associated with another DMRS CDM group, Link signal receiving method.
The method according to claim 1,

Wherein the length of the OCC is set equal to the number of PT-RS ports sharing a resource region for the PT-RS.
18. The method of claim 17,

Wherein the number of PT-RS ports sharing a resource region for the PT-RS is equal to the number of sub-carriers for which the PT-RS is received in one resource block.
A communication apparatus for receiving a downlink signal in a wireless communication system,

Memory; And

And a processor coupled to the memory,

The processor comprising:

Receiving information on a demodulation reference signal (DMRS) port index allocated to the UE from the BS; And

And receiving a downlink signal including a phase tracking reference signal (PT-RS) transmitted through a plurality of sub-carriers for the allocated DMRS port index,

The PT-RS is received based on an Orthogonal Cover Code (OCC)

Wherein the OCC is determined based on the assigned DMRS port index.
A communication apparatus for transmitting a downlink signal in a wireless communication system,

Memory; And

And a processor coupled to the memory,

The processor comprising:

Transmitting information on a demodulation reference signal (DMRS) port index assigned to one or more terminals to the one or more terminals; And

And transmit the downlink signal including the at least one terminal's phase tracking reference signal (PT-RS) to the at least one terminal,

The one or more terminal-specific PT-RSs are transmitted based on an associated Orthogonal Cover Code (OCC) through a plurality of sub-carriers for a DMRS port index assigned to the associated terminal,

Wherein the one or more per-terminal related OCCs are determined based on a DMRS port index assigned to the one or more terminals.