Method and apparatus for transmitting and receiving sounding reference signal

Abstract

A method according to an embodiment of the present specification comprises the steps of: receiving configuration information including a configuration for an SRS resource from a base station; and transmitting an SRS to the base station on the basis of the SRS resource. The number of ports configured for the SRS resource is 4. On the basis of i) the configuration information, ii) DCI related to the SRS, and / or iii) a MAC CE related to the SRS, the SRS is transmitted on the basis of three ports among four ports.

Description

Method for transmitting and receiving sounding reference signals and device therefor

[0001] This specification relates to a method for transmitting and receiving a sounding reference signal and a device therefor.

[0002] Mobile communication systems were developed to provide voice services while ensuring user activity. However, they have expanded beyond voice to include data services. Currently, explosive growth in traffic is leading to resource shortages and users are demanding faster services, necessitating a more advanced mobile communication system.

[0003] Next-generation mobile communication systems must support explosive data traffic growth, dramatically increasing data rates per user, a vastly increased number of connected devices, ultra-low end-to-end latency, and high energy efficiency. To achieve these goals, various technologies are being studied, including dual connectivity, massive multiple input multiple output (MIMO), in-band full duplex, non-orthogonal multiple access (NOMA), super wideband support, and device networking.

[0004] According to the current standard, the number of ports configured for SRS resources is 1, 2, 4, or 8. Therefore, UL transmissions based on 1, 2, 4, or 8 antenna ports (e.g., 1, 2, 4, or 8 Tx UL transmissions) are supported.

[0005] Rel-19 is expected to introduce 3Tx UL transmission, requiring SRS transmission based on three ports to support uplink transmission of 3Tx UEs. As previously explained, existing SRS resources are defined to configure only the number of ports 1, 2, 4, or 8. Therefore, SRS transmission based on three ports is not supported according to the existing method.

[0006] The purpose of this specification is to propose a method to support SRS transmission based on three ports.

[0007] The technical problems to be achieved in this specification are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art to which the present invention pertains from the description below.

[0008] A method according to one embodiment of the present disclosure includes the steps of receiving configuration information including configuration for a Sounding Reference Signal (SRS) resource from a base station and transmitting an SRS to the base station based on the SRS resource.

[0009] The number of ports set in the above SRS resource is 4. Based on i) the setting information, ii) downlink control information (DCI) related to the SRS, and / or iii) MAC CE (Medium Access Control Control Element) related to the SRS, the SRS is characterized in that it is transmitted based on 3 ports out of 4 ports.

[0010] Frequency domain resources associated with the four ports may be determined based on the transmission comb number associated with the SRS resource. The SRS may be transmitted based on the frequency domain resources associated with the three ports.

[0011] The above three ports can be determined in ascending order of port index.

[0012] The above three ports can be determined based on the above configuration information, the DCI or the MAC CE.

[0013] Based on the above setting information, the DCI or the MAC CE, three of the four ports may be enabled.

[0014] Based on the above setting information, the DCI or the MAC CE, the remaining ports among the four ports other than the three ports may be disabled.

[0015] The cyclic shifts associated with each of the four ports can be determined based on the maximum number of cyclic shifts.

[0016] The sequence associated with the above SRS resource can be generated based on the cyclic shifts associated with the above three ports.

[0017] The above three ports can be determined in ascending order of port index.

[0018] The above three ports can be determined based on the above configuration information, the DCI or the MAC CE.

[0019] Based on the above maximum number being a multiple of 3, the value for determining the cyclic shift for each port can be determined based on the product of the above maximum number and the index of each port.

[0020] Based on the fact that the above maximum number is a value other than a multiple of 3, the value for determining the cyclic shift for each port can be determined based on the product of the number of ports and the index of each port.

[0021] The above SRS may be transmitted based on a first frequency domain resource and a second frequency domain resource. The first frequency domain resource may be associated with two first ports among the three ports. The second frequency domain resource may be associated with a second port among the three ports.

[0022] The first transmit power associated with each of the two first ports and the second transmit power associated with the second port may be the same.

[0023] The power boosting factor associated with the second port may be different from the power boosting factor associated with each of the two first ports.

[0024] The above two first ports and the above second port can be determined based on rules.

[0025] The two first ports and the second port may be determined based on the configuration information, the DCI or the MAC CE.

[0026] The above three ports can be ports 1000, 1001, and 1002.

[0027] The above DCI may include an SRS request field related to the trigger of the SRS.

[0028] The above MAC CE may be related to the activation of the above SRS.

[0029] A terminal according to another embodiment of the present disclosure includes one or more transceivers, one or more processors, and one or more memories connected to the one or more processors and storing instructions.

[0030] The above instructions are characterized in that they cause the terminal to perform all steps of any one of the above methods based on being executed by the one or more processors.

[0031] According to another embodiment of the present disclosure, a device comprises one or more memories and one or more processors connected to the one or more memories. The one or more memories are characterized in that they store instructions that cause the device to perform all steps of any one of the above methods based on instructions executed by the one or more processors.

[0032] In another embodiment of the present disclosure, one or more non-transitory computer-readable storage media store instructions, executable by one or more processors, characterized in that the instructions cause a terminal to perform all steps of any one of the above methods.

[0033] A method according to another embodiment of the present disclosure includes the steps of transmitting configuration information including configuration for a Sounding Reference Signal (SRS) resource to a terminal and receiving an SRS from the terminal based on the SRS resource.

[0034] The number of ports set in the above SRS resource is 4. Based on i) the setting information, ii) downlink control information (DCI) related to the SRS, and / or iii) MAC CE (Medium Access Control Control Element) related to the SRS, the SRS is characterized in that it is transmitted based on 3 ports out of 4 ports.

[0035] A base station according to another embodiment of the present disclosure includes one or more transceivers, one or more processors, and one or more memories coupled to the one or more processors and storing instructions.

[0036] The above instructions are characterized in that they cause the base station to perform all steps of the method based on being executed by the one or more processors.

[0037] According to an embodiment of the present specification, SRS transmission based on 3 ports is supported by reusing existing SRS resources configured for 4 ports. Implementation complexity can be reduced by minimizing enhancements to SRS resources required to support 3Tx UL transmission.

[0038] The effects that can be obtained from this specification are not limited to the effects mentioned above, and other effects that are not mentioned can be clearly understood by a person having ordinary skill in the technical field to which this specification belongs from the description below.

[0039] Figure 1 is a flowchart showing an example of a UL BM procedure using SRS.

[0040] Figure 2 illustrates a port-specific comb according to an embodiment of the present specification.

[0041] FIG. 3 is a flowchart illustrating a method according to one embodiment of the present specification.

[0042] FIG. 4 is a flowchart illustrating a method according to another embodiment of the present specification.

[0043] FIG. 5 is a drawing showing the configuration of a first device and a second device according to an embodiment of the present specification.

[0044] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The detailed description set forth below, together with the accompanying drawings, is intended to illustrate exemplary embodiments of the present invention and is not intended to represent the only embodiments in which the present invention may be practiced. The following detailed description includes specific details to provide a thorough understanding of the present invention.

[0045] In some cases, to avoid obscuring the concept of the present invention, well-known structures and devices may be omitted or illustrated in block diagram form focusing on the core functions of each structure and device.

[0046] Hereinafter, downlink (DL) refers to communication from a base station to a terminal, and uplink (UL) refers to communication from a terminal to a base station. In downlink, a transmitter may be part of a base station, and a receiver may be part of a terminal. In uplink, a transmitter may be part of a terminal, and a receiver may be part of a base station. A base station may be expressed as a first communication device, and a terminal may be expressed as a second communication device. A base station (BS) may be replaced by terms such as a fixed station, Node B, eNB (evolved-NodeB), gNB (Next Generation NodeB), BTS (base transceiver system), access point (AP: Access Point), network (5G network), AI system, RSU (road side unit), vehicle, robot, drone (Unmanned Aerial Vehicle, UAV), AR (Augmented Reality) device, VR (Virtual Reality) device, etc. In addition, the terminal may be fixed or mobile, and may be replaced with terms such as UE (User Equipment), MS (Mobile Station), UT (user terminal), MSS (Mobile Subscriber Station), SS (Subscriber Station), AMS (Advanced Mobile Station), WT (Wireless terminal), MTC (Machine-Type Communication) device, M2M (Machine-to-Machine) device, D2D (Device-to-Device) device, vehicle, robot, AI module, drone (Unmanned Aerial Vehicle, UAV), AR (Augmented Reality) device, VR (Virtual Reality) device, etc.

[0047] <SRS related actions>

[0048] A UE can be configured with one or more Sounding Reference Symbol (SRS) resource sets (via higher layer signaling, RRC signaling, etc.) configured by (higher layer parameter) SRS-ResourceSet. For each SRS resource set, the UE can be configured with K≥1 SRS resources (higher layer parameter SRS-resource). Here, K is a natural number, and the maximum value of K is indicated by SRS_capability.

[0049] Figure 1 is a flowchart showing an example of a UL BM procedure using SRS.

[0050] - The terminal receives RRC signaling (e.g., SRS-Config IE) containing usage parameters from the base station (S110). For example, the upper layer parameter usage of each SRS resource set can be set to 'beam management', 'codebook', 'nonCodebook', or 'antennaSwitching'.

[0051] Table 1 shows an example of an SRS-Config IE (Information Element), which is used to configure SRS transmission. The SRS-Config IE includes a list of SRS-Resources and a list of SRS-ResourceSets. Each SRS resource set represents a set of SRS-resources.

[0052] The network can trigger the transmission of an SRS resource set using the configured aperiodicSRS-ResourceTrigger (L1 DCI).

[0053]

[0054] In Table 1, 'spatialRelationInfo' is a parameter that indicates the establishment of a spatial relation between a reference RS and a target SRS. Here, the reference RS can be an SSB, CSI-RS, or SRS corresponding to the L1 parameter 'SRS-SpatialRelationInfo'.

[0055] - The terminal determines the Tx beam for the SRS resource to be transmitted based on the SRS-SpatialRelation Info included in the SRS-Config IE (S120). Here, the SRS-SpatialRelation Info is set for each SRS resource and indicates whether to apply the same beam as the beam used in SSB, CSI-RS, or SRS for each SRS resource. In addition, the SRS-SpatialRelationInfo may or may not be set for each SRS resource.

[0056] - If SRS-SpatialRelationInfo is set in the SRS resource, the same beam used in SSB, CSI-RS, or SRS is applied for transmission. However, if SRS-SpatialRelationInfo is not set in the SRS resource, the terminal randomly determines a Tx beam and transmits SRS through the determined Tx beam (S130).

[0057] - Additionally, the terminal may or may not receive feedback on SRS from the base station (S140).

[0058] At least one of the operations of the terminal / base station based on S110 to S140 described above can be applied in combination with an embodiment related to SRS resource to support 3 Tx uplink transmission described below (e.g., an embodiment based on at least one of Proposals 1 to 5).

[0059] Below, we will look at the contents related to uplink power control.

[0060] < Power control of sounding reference signal >

[0061] Below, we will examine power control methods for the Sounding Reference Signal (SRS). A transmission occasion (i.e., a transmission time unit) (i) for the SRS can be defined by a slot index (n_s) within a frame of a system frame number (SFN), the first symbol (S) within the slot, and the number of consecutive symbols (L).

[0062] In relation to the transmission of a sounding reference signal (SRS) in an activated UL BWP of a carrier (f) of a serving cell (c), a terminal can calculate a linear power value of the transmission power determined by the following mathematical expression 1. Thereafter, the terminal can control the transmission power by equally dividing the calculated linear power value for the antenna port(s) configured for SRS.

[0063] Specifically, when the terminal performs SRS transmission in the activated UL BWP (b) of the carrier (f) of the serving cell (c) using the SRS power control adjustment state based on the index l, the terminal determines the SRS transmission power at the SRS transmission opportunity (i) based on the following mathematical expression 1. (dBm) can be determined.

[0064]

[0065] In mathematical equation 1, is the open-loop power control parameter (e.g., Po, alpha, ), path loss (PL) measurement (e.g. ) represents an index for DL ​​RS resources, etc., and can be set for each SRS resource set. Index l represents an index for a closed-loop power control process, and the index can be set independently of the PUSCH or can be set in association with it. If the SRS power control is not associated with the PUSCH, the maximum number of closed-loop power control processes for the SRS can be 1.

[0066] Specifically, Po (e.g., ) is a parameter broadcast as part of the system information and can indicate the target reception power at the receiving end. The Po value can be set by considering the terminal's throughput, cell capacity, noise, and / or interference. In addition, alpha (e.g., ) can represent the rate at which compensation for path loss is performed. Alpha can be set to a value from 0 to 1, and depending on the set value, full path loss compensation or fractional path loss compensation can be performed. In this case, the alpha value can be set in consideration of interference between terminals and / or data rate, etc.

[0067] also, may represent the configured terminal transmission power. For example, the configured terminal transmission power may be interpreted as the 'configured maximum UE output power' defined in 3GPP TS 38.101-1 and / or TS38.101-2. In addition, can represent the bandwidth of SRS resource allocation expressed as the number of resource blocks (RBs) for SRS transmission opportunities based on the subcarrier spacing (μ). In addition, related to the SRS power control adjustment state may be set or indicated based on the TPC command field and / or RRC parameter (e.g., srs-PowerControlAdjustmentStates, etc.) of DCI (e.g., DCI format 2_3, etc.) received or detected by the terminal.

[0068] Resources for SRS transmission may be applied as a reference for a base station and / or a terminal to determine beams, panels, and / or spatial domain transmission filters, and considering this, SRS transmission power control may be performed on a beam, panel, and / or spatial domain transmission filter basis.

[0069] The parameters and / or information for the above-described SRS power control can be individually (i.e., independently) set for each BWP. In this case, the parameters and / or information can be set or indicated via higher layer signaling (e.g., RRC signaling, MAC-CE, etc.) and / or DCI, etc. For example, the parameters and / or information for SRS power control can be conveyed via RRC signaling SRS-Config, SRS-TPC-CommandConfig, etc.

[0070] Through the method described above, the terminal can determine or calculate SRS transmission power, and transmit SRS using the determined or calculated SRS transmission power.

[0071] The previously discussed topics (e.g., SRS-related operations, power control of sounding reference signals) can be applied in conjunction with the methods proposed in this specification, which will be described later, or can be supplemented to clarify the technical characteristics of the methods proposed in this specification. The methods described below are distinguished merely for convenience of explanation, and it is obvious that some components of one method can be substituted for some components of another method, or they can be applied in combination with each other.

[0072] Existing NR (New Radio) supports Sounding Reference Signal (SRS) for 1 / 2 / 4 / 8 Tx uplink transmission. Specifically, the number of ports configured for SRS resources is 1, 2, 4, or 8.

[0073] As shown below, discussions are underway in Rel 19 to introduce 3 Tx uplink transmission (e.g. 3 port codebook based UL transmission).

[0074] Specify non-coherent UL codebook to facilitate 3-antenna-port codebook-based transmissions, without enhancement on UL full power transmission and without enhancement on SRS resource

[0075] Note: UL full power transmission mode 1 and 2 are not supported.

[0076] This specification proposes methods for configuring SRS resources to support 3 Tx uplink transmission. In this specification, the term "port" related to SRS may be interpreted / replaced with "port," "antenna port," "SRS port," or "SRS antenna port."

[0077] Proposal 1

[0078] For 3-port Tx SRS, a method of transmitting 3 SRS ports based on 3 comb values ​​out of 4 comb values ​​may be considered. The 4 comb values ​​may be based on a specific SRS resource in which 4 SRS ports are set. For example, the number of ports of the specific SRS resource ( ) may be 4. As a more specific example, the specific SRS resource may be an SRS resource with the upper layer parameter 'nrofSRS-Ports' set to ports4 (see Table 1). Here, comb (or comb value) may mean a transmission comb associated with the SRS. The number of combs (e.g., ) can be determined as 2, 4 or 8 based on the upper layer parameter transmissionComb.

[0079] According to this embodiment, the existing legacy SRS resource configuration / transmission method can be reused. The existing 4 port SRS resource (e.g., =4) 4 combs determined / set (e.g. =4) Only 3 combs can be utilized / used.

[0080] This embodiment has the advantage of being able to multiplex legacy UEs (e.g., 1 / 2 / 4 / 8 Tx UEs) and 3Tx UEs because it reuses existing legacy settings. For example, a 4-port UE (4Tx UE) can be configured to transmit using the same comb as a 3Tx UE by differentiating the CS (Cyclic Shift) value. For example, when multiplexing a 1-port UE (1Tx UE) and a 3Tx UE, the 1-port UE (1Tx UE) can be configured to transmit using the remaining comb among the 4 combs.

[0081] At this time, in order to facilitate 1-port SRS and multiplexing, the setting / instruction method for the comb used for 3-port Tx SRS is described in detail below.

[0082] Proposal 1-1

[0083] The comb used for a specific 3-port Tx SRS resource can be configured / determined in a specific rule-based manner. Four combs ( =4) Three combs can be determined based on the rules.

[0084] For example, the three combs may be three combs related to ports 1000, 1001, and 1002. Specifically, the three combs related to ports 1000, 1001, and 1002 may refer to three combs determined in ascending order of port index among the four combs related to ports 1000 to 1003 of a 4-port SRS.

[0085] For example, the three combs may be three combs related to ports 1001, 1002, and 1003. Specifically, the 'three combs related to ports 1001, 1002, and 1003' may mean three combs determined in descending order of port index among the four combs related to ports 1000 to 1003 of the existing 4-port SRS.

[0086] At this time, if another 1-port SRS is multiplexed, the last comb can be used. According to this embodiment, the signaling overhead required to indicate SRS transmission based on 3 ports can be reduced. Specifically, according to this embodiment, signaling overhead is reduced because signaling is not required to indicate 3 of the 4 comb values.

[0087] Proposal 1-2

[0088] The comb used for a specific 3-port Tx SRS resource of the above proposal 1 can be explicitly set / indicated. Four combs ( =4) Three combs can be set / directed based on signaling.

[0089] For example, a base station can signal to a terminal which comb(s) to use for a given SRS resource. For example, a base station can signal to a terminal which comb(s) not to use for a given SRS resource.

[0090] In one embodiment, three comb value combinations can be predefined based on the port index of the SRS. The base station can indicate one of the defined combinations to the terminal via 1-bit signaling (e.g., Table 2) or / and 2-bit signaling (e.g., Table 3). In this case, information based on the signaling can be transmitted based on RRC (e.g., SRS-config), MAC CE, or DCI.

[0091] For example, a configuration related to SRS (e.g., SRS-config) may include upper layer parameters (RRC parameters) related to determining three of four ports. As a specific example, three of the four ports may be indicated based on the upper layer parameters (RRC parameters) (e.g., only ports 1000, 1001, and 1002 are enabled). As a specific example, one of the four ports may be indicated based on the upper layer parameters (RRC parameters) (e.g., port 1003 is disabled).

[0092]

[0093] Table 2 is an example of the 1-bit signaling described above.

[0094]

[0095] In one embodiment, a full bitmap (e.g., a 4-bit bitmap) can be used to indicate which comb value to use or not to use.

[0096] For example, a bitmap indicating the comb value to be used may be indicated. A value of "1110" in the bitmap may indicate that ports 1000, 1001, and 1002 (corresponding comb values) are to be utilized for 3 Tx SRS transmission.

[0097] For example, a bitmap may be indicated indicating comb values ​​that are not to be used. A value of "0001" in that bitmap may indicate that port 1003 (corresponding comb value) is not to be utilized for 3 Tx SRS transmission.

[0098] In one embodiment, a method may be considered for indicating which comb value to use and / or not to use using 2-bit or full bitmap signaling. This will be described in detail below.

[0099] For example, if the 3rd comb is not used, the base station indicates "10" to the terminal through a 2-bit bitmap. In this case, ports 1000, 1001, and 1002 can be sequentially set to the 1st, 2nd, and 4th combs. In this case, if a 1-port SRS is multiplexed, the 3rd comb can be used for the 1-port SRS. In this embodiment, the number of bits can be reduced because 2 bits are used instead of the full bitmap (4 bits).

[0100] The resource type (resourceType) associated with the above-described SRS resource may be periodic, aperiodic, or semi-persistent. For example, the SRS may be a P SRS, an AP SRS, or an SP SRS.

[0101] Below, specific examples related to the signaling of the above proposals 1-2 are described.

[0102] For example, one of the comb value combinations of the above proposals 1-2 can be indicated by an RRC setting (RRC parameter).

[0103] For example, one of the combination candidates may be indicated via triggering DCI (Downlink Control Information) / MAC CE (Medium Access Control Element). As a specific example, the DCI may include DCI that triggers AP SRS.

[0104] For example, information (e.g., a 1 / 2 bit codepoint or bitmap) according to the above-described embodiments may be transmitted based on the MAC CE message format. As a specific example, the MAC CE message may include a MAC CE message format that activates transmission of the SP SRS.

[0105] For example, a bit field may exist in the payload of the DCI to indicate information according to the embodiments described above. The DCI may include a DCI that triggers an AP SRS.

[0106] For example, the combination candidates may be set via RRC and one of the combination candidates may be indicated via DCI / MAC CE.

[0107] The following specifically explains the meaning of setting / instruction of a specific comb value combination for 3-port SRS resource transmission in the embodiments of Proposals 1-1 and 1-2.

[0108] For example, the above-described settings / instructions of the above-described proposals 1-1 and 1-2 may mean to transmit the corresponding 3-port SRS resource by utilizing the combination of the corresponding comb value and the combination of the port index (e.g., 3 port indexes among 1000 to 1003) corresponding to the corresponding comb value combination in the 4-port SRS resource.

[0109] For example, the above setting / instruction of the above suggestions 1-1 to 1-2 may mean to transmit the corresponding 3-port SRS resource by utilizing the SRS port index 1000, 1001, 1002 ports (in ascending order) for the corresponding comb value combination.

[0110] Proposal 2

[0111] According to the existing method, the number of transmission combs (e.g., ) are supported as 1, 2, 4 or 8. For example, values ​​(n2, n4 or n8) based on the upper layer parameter transmissionComb are Indicates that the number of bits is 2, 4 or 8. As a concrete example, by the upper layer parameter transmissionComb can be determined as 2 or 4, by the upper layer parameter transmissionComb-n8. It can be decided as 8.

[0112] In one embodiment, to support 3-port Tx SRS, as shown in FIG. 2, Setting it to =3 may be considered.

[0113] Figure 2 illustrates a port-specific comb according to an embodiment of the present specification.

[0114] Referring to Figure 2, for 3-port Tx SRS =3 can be set. For example, based on the upper layer parameter transmissionComb. can be determined as 3. As a concrete example, by the upper layer parameter transmissionComb can be determined as 2, 3 or 4. As another example, by the upper layer parameter transmissionComb-n3 It can be determined as 3.

[0115] Three combs based on =3 can be associated with ports 1000, 1001, 1002.

[0116] According to the existing method =4 is set so that the given frequency resources cannot be fully utilized when transmitting 3-port SRS. As in the above proposal 2. Setting it to =3 and transmitting 3 port SRS has the advantage of being able to fully utilize the given frequency resources.

[0117] Proposal 3

[0118] For 3-port Tx SRS, a method of transmitting SRS using 3 CS (cyclic shift) values ​​among 4 CS values ​​can be considered.

[0119] According to this embodiment, the existing legacy SRS resource configuration / transmission method can be reused. The existing 4 port SRS resource (e.g., =4) Only 3 CS values ​​out of the 4 CS values ​​determined / set for can be utilized / used.

[0120] This embodiment has the advantage of being able to multiplex legacy UEs (e.g., 1 / 2 / 4 / 8 Tx UEs) and 3Tx UEs because it reuses existing legacy settings. For example, a 4-port UE (4Tx UE) can be configured to transmit using the same CS value as a 3Tx UE by differentiating the comb offset. For example, when a 1-port UE (1Tx UE) is multiplexed with a 3Tx UE, the 1-port UE (1Tx UE) can be configured to transmit using the unused CS value.

[0121] At this time, in order to facilitate multiplexing with 1-port SRS, the setting / instruction method for the CS value used in 3-port Tx SRS is described in detail below.

[0122] Proposal 3-1

[0123] The CS value used for a specific 3-port Tx SRS resource can be set / determined in a specific rule-based manner. Three of the four CS values ​​can be determined based on the rules.

[0124] For example, the three CS values ​​above are It can be. Specifically, the above three CS values ​​can mean three CS values ​​determined in ascending order of port index (e.g., port 1000, 1001, 1002) among four CS values.

[0125] For example, the three CS values ​​above are It can be. Specifically, the three CS values ​​above can mean three CS values ​​determined in descending order of port index (e.g., port 1003, 1002, 1001) among the four CS values.

[0126] As above, rule-based 3 CS values ​​can be utilized for 3 ports.

[0127] 4 port SRS resource (e.g. 4 CS values ​​determined for =4) middle Ports 1000, 1001, and 1002 can be allocated respectively. In this case, if another 1-port SRS is multiplexed, the last CS value can be used for the corresponding 1-port SRS. According to this embodiment, the signaling overhead required to indicate SRS transmission based on 3 ports can be reduced. Specifically, according to this embodiment, signaling overhead is reduced because signaling for indicating 3 out of 4 CS values ​​is not required.

[0128] Proposal 3-2

[0129] The CS value used for a specific 3-port Tx SRS of the above proposal 3 can be explicitly set / indicated.

[0130] For example, a base station can signal to a terminal which CS value(s) to use for a given SRS resource. For example, a base station can signal to a terminal which CS value(s) not to use for a given SRS resource.

[0131] In one embodiment, combinations of three CS values ​​may be predefined. The base station may indicate one of the defined combinations to the terminal using 1-bit signaling (e.g., Table 4 or Table 5) or / and 2-bit signaling (e.g., Table 6).

[0132]

[0133]

[0134]

[0135] In one embodiment, a full bitmap (e.g., a 4-bit bitmap) can be used to indicate which CS value to use or not to use.

[0136] For example, a bitmap indicating the comb value to use can be indicated. The value of that bitmap, "1110", is the CS value. This may mean that 3 Tx SRS is used for transmission.

[0137] For example, a bitmap indicating comb values ​​that will not be used can be indicated. The value "0001" in that bitmap is the CS value This may mean that 3 Tx is not utilized for SRS transmission.

[0138] In one embodiment, a method may be considered for indicating which CS value to use and / or not to use using 2-bit or full bitmap signaling. This will be described in detail below.

[0139] For example, if the second CS value is not used, the base station indicates "01" to the terminal through a 2-bit bitmap. In this case, ports 1000, 1001, and 1002 correspond to the 1st, 3rd, and 4th CS values. can be set in order. At this time, if 1-port SRS is multiplexed, the second CS value for 1-port SRS can be used. In this embodiment, the number of bits can be reduced because 2 bits are used instead of the full bitmap (4 bits).

[0140] The resource type (resourceType) associated with the above-described SRS resource may be periodic, aperiodic, or semi-persistent. For example, the SRS may be a P SRS, an AP SRS, or an SP SRS.

[0141] Below, specific examples related to the signaling of the above proposal 3-2 are described.

[0142] For example, one of the CS value combinations of the above proposal 3-2 can be indicated by an RRC setting (RRC parameter).

[0143] For example, one of the combination candidates may be indicated via triggering DCI (Downlink Control Information) / MAC CE (Medium Access Control Element). As a specific example, the DCI may include DCI that triggers AP SRS.

[0144] For example, information (e.g., a 1 / 2 bit codepoint or bitmap) according to the above-described embodiments may be transmitted based on the MAC CE message format. As a specific example, the MAC CE message may include a MAC CE message format that activates transmission of the SP SRS.

[0145] For example, a bit field may exist in the payload of the DCI to indicate information according to the embodiments described above. The DCI may include a DCI that triggers an AP SRS.

[0146] For example, the combination candidates may be set via RRC and one of the combination candidates may be indicated via DCI / MAC CE.

[0147] In the embodiments of the following proposals 3-1 and 3-2, the meaning of the specific CS value combinations set / instructed for 3-port SRS resource transmission is specifically explained.

[0148] For example, the above-described settings / instructions of the above-described proposals 3-1 and 3-2 may mean to transmit the 3-port SRS resource by utilizing the combination of the CS value and the port index (e.g., 3 port indexes among 1000 to 1003) corresponding to the CS value combination in the 4-port SRS resource.

[0149] For example, the above-described settings / instructions of proposals 3-1 and 3-2 may mean to transmit the corresponding 3-port SRS resource by utilizing ports with SRS port indexes 1000, 1001, and 1002 (in ascending order) for a specific CS value combination.

[0150] Proposal 4

[0151] A method to set / determine a new CS value for a specific 3-port Tx SRS may be considered.

[0152] =4, 8 cases (maximum number of cyclic shifts) is a multiple of 3. In this case, there is no problem with 3-port Tx SRS transmission even if the CS value determined according to the existing method is used. Specifically, If the number is 4 is 12, If it is 8 is 6.

[0153] But in 3-port Tx SRS If set to =2, =8. In this case, the maximum number of CSs is not divisible by 3. Considering this, we propose a new CS value setting / determination method for 3-port Tx SRS.

[0154] Proposal 4-1

[0155] Used for the specific 3-port Tx SRS of the above proposal 4. = In case of 4,8, the existing legacy SRS resource method can be reused.

[0156] Specifically, the CS value is an index related to the number of ports based on the following mathematical expression 2. It can be set / determined by the stars.

[0157]

[0158] Here, is the number of ports, is the port index am. And, is the value indicated by the cyclicShift parameter in the upper layer parameter transmissionComb. am.

[0159] For example, If =4 =12. =3, Assuming =0, 1000, 1001, 1002 port( There are three CS values ​​for =0, 1, 2) can be decided by =4, Assuming =0, 1000, 1001, 1002 port( There are three CS values ​​for =0, 1, 2) can be decided by

[0160] Proposal 4-2

[0161] For the specific 3-port Tx SRS of the above proposal 4 If set to =2, the CS values ​​may be set / determined so that the distance between CS values ​​is not the same.

[0162] In the existing legacy SRS resource transmission method, Since the CS value is divided by the number of ports, each CS value set to a port can be set to be as far apart as possible based on the same distance. In other words, two consecutive ports (e.g., =0, 1) The interval / distance of the CS values ​​set / determined for is the same.

[0163] In case of =2 (8) Since it is not divisible by 3, the CS values ​​cannot be set to have the same distance. Therefore, the CS values ​​can be set based on the following mathematical expression 3 so that the deviation of each CS value distance is the smallest.

[0164]

[0165] =2, Assuming =3, the CS values ​​for ports 1000, 1001, and 1002 are can be decided by =2, Assuming =4, the CS values ​​for ports 1000, 1001, and 1002 are According to this embodiment, in an environment where it is difficult to have CS values ​​of the same distance, the deviation of each CS value distance can be transmitted with the smallest possible difference.

[0166] Proposal 4-3

[0167] For the specific 3-port Tx SRS of the above proposal 4 If set to =2 can be redefined.

[0168] In the existing legacy SRS resource transmission method To solve the problem that the number of ports was not divisible by is defined as 12. In this case, the existing method for determining the CS value can be reused. The CS value can be determined based on the mathematical expression 2 described above.

[0169] For example, ports 1000, 1001, 1002 port( There are three CS values ​​for =0, 1, 2) can be decided by

[0170] Proposal 5

[0171] In 3-port Tx SRS ( =4) A method of dividing 3 ports into 2 ports + 1 port and transmitting them to 2 combs among 2 combs and 2 CS values ​​can be considered.

[0172] Previously defined According to is as shown in Table 7 below.

[0173]

[0174] 3-port Tx SRS can be transmitted by dividing 3 ports into 2 ports + 1 port to 2 configured combs.

[0175] The CS value for each port is in the mathematical formula 4 below. =4 and =Can be set in the same way as when 6.

[0176]

[0177] For example, For ports 1000, 1001, the CS value can be set to 0, and for port 1002, the CS value can be set to 0. can be set to . Ports 1000 and 1002 can be independently set to the 1st comb and port 1001 to the 2nd comb. In this case, 1 port SRS has the CS value set to the same comb as port 1001. It has the advantage of being able to multiplex by setting it to .

[0178] Based on the above suggestion 4, mathematical expression 4 can be modified as in mathematical expression 5 below.

[0179]

[0180] Proposal 5-1

[0181] If transmission is performed as in the above proposal 4, three ports can be transmitted through two combs. However, since the number of ports in the two combs is not identical, the power for each port varies. If the power for each port varies, the channel estimation quality may vary for each port. To compensate for this, the following embodiment can be considered. Different power boosting factors can be applied to different combs. For example, a different power boosting factor can be applied to port 1001 (the second comb) than to ports 1000 and 1002 (the first comb). This allows the power for port 1001 to be matched to the power of each of the other two ports (ports 1000 and 1002).

[0182] Proposal 5-2

[0183] ( =6) The comb set for 3-port Tx SRS can be set / determined based on a specific rule. The comb for each port can be set / determined based on a rule.

[0184] For example, the comb for ports 1000 and 1002 may be determined as the 1st comb, and the comb for port 1001 may be determined as the 2nd comb. For example, the comb for ports 1000 and 1002 may be determined as the 1st comb, and the comb for port 1003 may be determined as the 2nd comb. In this case, the 2nd comb may be used when another 1-port SRS is multiplexed.

[0185] For example, the comb for port 1000 may be determined as the 1st comb, and the combs for ports 1001 and 1003 may be determined as the 2nd comb. For example, the comb for port 1002 may be determined as the 1st comb, and the combs for ports 1001 and 1003 may be determined as the 2nd comb. In this case, the 1st comb may be used when another 1-port SRS is multiplexed.

[0186] According to this embodiment, overhead can be reduced and resources can be used efficiently without signaling indicating the comb value.

[0187] Proposal 5-3

[0188] ( =6) A method of explicitly indicating the comb to be configured for 3-port Tx SRS may be considered. Two combs may be configured / indicated based on signaling.

[0189] For example, a base station can signal to a terminal which comb(s) to use for a given SRS resource. For example, a base station can signal to a terminal which comb(s) not to use for a given SRS resource.

[0190] In one embodiment, the base station may configure / instruct the terminal which port is to be configured for which comb by utilizing 1 bit signaling (Tables 8 to 11) or / and 2 bit signaling (Table 12).

[0191] Tables 8 to 12 below illustrate comb / CS value (port) combinations for 3 Tx SRS resources.

[0192]

[0193]

[0194]

[0195]

[0196]

[0197] In one embodiment, the base station can use 2 bit signaling to set / instruct the terminal which comb value to use for the two ports.

[0198] In one embodiment, the base station can use a 1-bit field to set / instruct the terminal to use a comb value for 1 port. For example, "0" can indicate that ports 1000 and 1002 are used for the 1st comb for 3Tx SRS transmission. For example, "1" can indicate that ports 1000 and 1002 are used for the 2nd comb for 3Tx SRS transmission. In this embodiment, the number of bits can be reduced because 1 bit is used instead of a full bitmap for 4 ports.

[0199] The resource type (resourceType) associated with the above-described SRS resource may be periodic, aperiodic, or semi-persistent. For example, the SRS may be a P SRS, an AP SRS, or an SP SRS.

[0200] Below, specific examples related to the signaling of the above proposal 5-3 are described.

[0201] For example, one of the comb / CS value combinations of the above proposal 3-2 may be indicated by an RRC setting (RRC parameter).

[0202] For example, one of the combination candidates may be indicated via triggering DCI (Downlink Control Information) / MAC CE (Medium Access Control Element). As a specific example, the DCI may include DCI that triggers AP SRS.

[0203] For example, information (e.g., 1 / 2 bit codepoint) according to the above-described embodiments may be transmitted based on the MAC CE message format. As a specific example, the MAC CE message may include a MAC CE message format that activates transmission of the SP SRS.

[0204] For example, a bit field may exist in the payload of the DCI to indicate information according to the embodiments described above. The DCI may include a DCI that triggers an AP SRS.

[0205] For example, the combination candidates may be set via RRC and one of the combination candidates may be indicated via DCI / MAC CE.

[0206] The following specifically explains the meaning of setting / instruction of a specific comb / CS value combination for 3-port SRS resource transmission in the embodiments of Proposals 5-2 to 5-3.

[0207] For example, the above setting / instruction of proposals 5-2 to 5-3 may mean to transmit the corresponding 3-port SRS resource by utilizing the combination of the corresponding comb / CS value combination and the port index (e.g., 3 port indexes among 1000 to 1003) corresponding to the corresponding comb / CS value combination in the 4-port SRS resource.

[0208] For example, the above settings / instructions of proposals 5-2 to 5-3 may mean to transmit the corresponding 3-port SRS resource by utilizing ports with SRS port indexes 1000, 1001, and 1002 (in ascending order) for the corresponding comb / CS value combination.

[0209] For example, the above-described proposals 1 through 5 may be individually applied to terminal / base station operations. For example, two or more embodiments of the above-described proposals 1 through 5 may be combined and applied to terminal / base station operations.

[0210] An example of a terminal (or base station) operation based on at least one of the embodiments described above (e.g., at least one of proposals 1 to 5) is as follows.

[0211] 1) The terminal (base station) receives (transmits) SRS-related setting information.

[0212] For example, the configuration information may include information based on the proposed method (e.g. at least one of proposals 1 / 2 / 3 / 4 / 5).

[0213] For example, based on the above configuration information, multiple spatialRelationInfo / TCIs ​​may be configured / indicated for SRS resources within a specific SRS resource set. Different sequence initialization factors, sequence (group) hopping patterns, frequency hopping patterns, RPFS patterns, comb offsets, comb offset hopping patterns, cyclic shifts, and cyclic shift hopping patterns may be configured / indicated for SRS resources (sets) having different desired / target TRPs.

[0214] 2) The terminal (base station) transmits (receives) SRS according to P / SP / AP-SRS transmission settings / activation / instructions.

[0215] The terminal transmits the SRS resource set(s) configured / activated / indicated by RRC / MAC CE / DCI based on the above proposed method (e.g., Proposal 1 / 2 / 3 / 4 / 5).

[0216] The above-described terminal / base station operations are only examples, and each operation (or step) is not necessarily essential, and operations related to SRS transmission of the terminal according to the above-described embodiments may be omitted or added depending on the terminal / base station implementation method.

[0217] In terms of implementation, the operations of the base station / terminal according to the embodiments described above (e.g., operations based on at least one of the embodiments of Proposals 1 to 5) can be processed by the device of FIG. 5 described below (e.g., processor (110, 210) of FIG. 5).

[0218] In addition, the operations of the base station / terminal according to the above-described embodiments (e.g., operations based on at least one of the embodiments of Proposals 1 to 5) may be stored in a memory (e.g., 140, 240 of FIG. 5) in the form of commands / programs (e.g., instructions, executable codes) for driving at least one processor (e.g., processor (110, 210) of FIG. 5).

[0219] The embodiments described below are specifically described with reference to FIGS. 3 and 4 in terms of the operation of the terminal and base station. The methods described below are distinguished for convenience of explanation, and it is understood that some components of one method may be substituted for or combined with some components of another method.

[0220] FIG. 3 is a flowchart illustrating a method according to one embodiment of the present specification.

[0221] Referring to FIG. 3, a method according to one embodiment of the present specification includes a step of receiving settings related to SRS (S310) and a step of transmitting SRS based on SRS resources (S320).

[0222] In S310, the terminal receives configuration information including configuration for Sounding Reference Signal (SRS) resources from the base station.

[0223] For example, the configuration information may include information related to an operation / configuration based on at least one of the above-described suggestions 1 to 5.

[0224] For example, the above configuration information may be based on the upper layer parameter SRS-Config of Table 1.

[0225] For example, the configuration for the SRS resource may be based on the upper layer parameter SRS-Resource within the upper layer parameter SRS-Config.

[0226] For example, the configuration information may include i) a list of one or more SRS resource sets (e.g., srs-ResourceSetToAddModList) and ii) a list of one or more SRS resources (e.g., srs-ResourceToAddModList). An SRS resource set may include at least one SRS resource. A configuration for an SRS resource set may include a list of SRS resource ID(s) representing the at least one SRS resource (e.g., srs-ResourceIdList).

[0227] For example, the number of ports set in the above SRS resource (e.g., ) is 4. As a specific example, nrofSRS-Ports in the upper layer parameter SRS-Resource can be set to "ports4". Port index Is It can be decided as +1000. is the number of the above ports (e.g. ) is an index related to ( ) The four ports set in the above SRS resource can be expressed as ports 1000, 1001, 1002, and 1003.

[0228] In S320, the terminal transmits an SRS to the base station based on the SRS resource.

[0229] In one embodiment, based on i) the configuration information, ii) downlink control information (DCI) related to the SRS, and / or iii) a medium access control element (MAC CE) related to the SRS, the SRS may be transmitted based on three of the four ports. The present embodiment may be based on at least one of proposal 1, proposal 3, and / or proposal 5.

[0230] For example, the DCI may include an SRS request field related to the triggering of the SRS. The SRS may be an aperiodic SRS.

[0231] For example, the MAC CE may be associated with the activation of the SRS. The SRS may be a semi-persistent SRS.

[0232] For example, information (e.g., information related to port, comb and / or CS) based on at least one of Proposal 1, Proposal 3 and / or Proposal 5 may be configured / indicated based on the configuration information, the DCI and / or the MAC CE. As a specific example, information related to port (e.g., information indicating disablement of one of four ports) may be configured based on the configuration information (or DCI / MAC CE), and information related to comb and / or CS (cyclic shift) may be indicated based on the DCI / MAC CE (or configuration information).

[0233] For example, the configuration information may include parameters related to transmission of the SRS based on three of the four ports. The parameters may include upper layer parameters (RRC parameters) based on at least one of Proposal 1, Proposal 3, and / or Proposal 5. The RRC parameters may be configured for each SRS resource or each SRS resource set.

[0234] For example, the DCI or the MAC CE may include a field related to transmission of the SRS based on three of the four ports. The field may indicate information based on at least one of Proposal 1, Proposal 3, and / or Proposal 5.

[0235] For example, the SRS resource may be based on an SRS resource(s) within an SRS resource set in which the upper layer parameter usage is set to 'codebook'. The parameter may be based on an RRC parameter set in the SRS resource set.

[0236] For example, the SRS resource may be based on an SRS resource(s) within an SRS resource set in which the upper layer parameter usage is set to 'antennaSwitching'. The parameter may be based on an RRC parameter set in the SRS resource set.

[0237] For example, the SRS may be transmitted based on three ports out of four ports set in the SRS resource.

[0238] In one embodiment, frequency domain resources associated with the four ports may be determined based on the transmission comb number associated with the SRS resource. The SRS may be transmitted based on the frequency domain resources associated with the three ports. This embodiment may be based on Proposal 1.

[0239] For example, the frequency domain resources associated with the four ports may be based on different frequency domain locations. The frequency domain starting location associated with each port may be determined based on the transmission comb number.

[0240] In one embodiment, the three ports are port indexed (e.g., ) can be determined in ascending (or descending) order. This embodiment can be based on Proposal 1-1. For example, the three ports can be ports 1000, 1001, and 1002. For example, the three ports can be ports 1001, 1002, and 1003.

[0241] In one embodiment, the three ports may be determined based on the configuration information, the DCI, or the MAC CE. This embodiment may be based on Proposal 1-2.

[0242] In one embodiment, three of the four ports may be enabled based on the configuration information, the DCI, or the MAC CE. As a specific example, ports 1000, 1001, and 1002 may be enabled based on i) a parameter in the configuration information, or ii) a field of the DCI or the MAC CE. This embodiment may be based on Proposal 1-2.

[0243] In one embodiment, the remaining ports, except for the three ports, among the four ports may be disabled based on the configuration information, the DCI, or the MAC CE. For example, one port among the four ports may be disabled based on i) a parameter in the configuration information or ii) a field of the DCI or the MAC CE. As a specific example, port 1003 may be disabled based on the parameter. This embodiment may be based on Proposal 1-2.

[0244] In one embodiment, the maximum number of cyclic shifts (e.g., ) and the cyclic shifts associated with each of the four ports (e.g., , ) can be determined. The sequence associated with the SRS resource can be generated based on the cyclic shifts associated with the three ports. The present embodiment can be based on at least one of Proposal 3, Proposal 4 and / or Proposal 5.

[0245] For example, the three ports may be determined in ascending order of port index. This embodiment may be based on Proposal 3-1. As a specific example, the sequence associated with the SRS resource may be generated based on cyclic shifts associated with ports 1000, 1001, and 1002.

[0246] For example, the three ports may be determined based on the configuration information, the DCI, or the MAC CE. This embodiment may be based on Proposal 3-2. As a specific example, cyclic shifts associated with the three ports may be determined / instructed based on i) parameters in the configuration information, or ii) fields of the DCI or the MAC CE (see Tables 4 to 6).

[0247] For example, based on the fact that the maximum number is a multiple of 3 (e.g., 6, 12), a value for determining the cyclic shift for each port (e.g., ) can be determined based on the product of the maximum number and the index of each port. This embodiment can be based on Proposal 4-1. More specifically, the value for determining the cyclic shift for each port (e.g., )silver can be determined based on. Here, is the maximum number above, is the port index, is the number of the above ports.

[0248] For example, based on the fact that the maximum number is a value other than a multiple of 3 (e.g., 8), a value for determining the cyclic shift for each port (e.g., ) can be determined based on the product of the number of ports and the index of each port. This embodiment can be based on Proposal 4-2. More specifically, the value for determining the cyclic shift for each port (e.g., )silver can be determined based on. Here, is the port index, is the number of the above ports.

[0249] In one embodiment, the SRS may be transmitted based on a first frequency domain resource and a second frequency domain resource. For example, each of the first / second frequency domain resources may be based on a frequency domain start position determined based on a transmission comb number (=2). For example, the first frequency domain resource may be associated with two first ports among the three ports. The second frequency domain resource may be associated with the second port among the three ports. This embodiment may be based on Proposal 5.

[0250] In one embodiment, the first transmission power associated with each of the two first ports and the second transmission power associated with the second port may be the same. This embodiment may be based on Proposal 5-1. For example, the power boosting factor associated with the second port may be different from the power boosting factor associated with each of the two first ports. In this embodiment, the transmission power for each port may be controlled to be identical. Therefore, it is possible to prevent the overall channel estimation quality from deteriorating due to the channel estimation quality varying for each port.

[0251] In one embodiment, the two first ports and the second port may be determined based on a rule. This embodiment may be based on Proposal 5-2.

[0252] In one embodiment, the two first ports and the second port may be determined based on the configuration information, the DCI, or the MAC CE. This embodiment may be based on Proposal 5-3.

[0253] In one embodiment, 3Tx UL transmission (e.g., codebook-based PUSCH transmission using 3 ports) may be performed after SRS transmission based on the 3 ports. Specifically, the method may further include a DCI reception step and a PUSCH transmission step.

[0254] In the DCI reception step, the terminal receives downlink control information (DCI) for scheduling a physical uplink shared channel (PUSCH) from the base station.

[0255] For example, the DCI may be based on DCI format 0_0, DCI format 0_1, DCI format 0_2, or DCI format 0_3.

[0256] For example, the DCI may include at least one of the following fields:

[0257] Identifier for DCI formats, UL / SUL (Supplementary uplink) indicator, Bandwidth part indicator, Frequency domain resource assignment, Time domain resource assignment, Frequency hopping flag, Modulation and coding scheme (MCS), SRS resource indicator (SRI), Precoding information and number of layers, Antenna port(s), SRS request, DMRS sequence initialization, UL-SCH (Uplink Shared Channel) indicator

[0258] In particular, the SRS resource indicator field may indicate the SRS resource(s) set within the SRS resource set associated with the upper layer parameter 'usage'. In addition, 'spatialRelationInfo' may be set for each SRS resource, and its value may be one of {CRI, SSB, SRI}.

[0259] In the PUSCH transmission step, the terminal transmits the PUSCH to the base station based on the DCI.

[0260] For example, the transmission scheme related to the PUSCH may be based on codebook-based transmission or non-codebook-based transmission. For example, the codebook-based transmission may be configured based on the upper layer parameter 'txConfig' being set to 'codebook' in the terminal. For example, the non-codebook-based transmission may be configured based on the upper layer parameter 'txConfig' being set to 'nonCodebook' in the terminal. The upper layer parameter txConfig may be configured based on configuration information related to the PUSCH (e.g., PUSCH-config).

[0261] For example, if the upper layer parameter 'txConfig' is not set, the terminal does not expect to be scheduled by DCI format 0_1. If PUSCH is scheduled by DCI format 0_0, PUSCH transmission is based on a single antenna port.

[0262] For example, for codebook-based transmission, PUSCH can be scheduled in DCI format 0_0, DCI format 0_1, or semi-statically. When this PUSCH is scheduled in DCI format 0_1, the UE determines the PUSCH transmission precoder based on the SRI, the Transmit Precoding Matrix Indicator (TPMI), and the transmission rank from the DCI, as provided by the SRS resource indicator field and the Precoding information and number of layers field. The TPMI is used to indicate the precoder to be applied across antenna ports, and corresponds to the SRS resources selected by the SRI when multiple SRS resources are configured.

[0263] Alternatively, when a single SRS resource is configured, the TPMI is used to indicate a precoder to be applied across antenna ports, corresponding to the single SRS resource. The transmit precoder is selected from an uplink codebook having the same number of antenna ports as the upper layer parameter 'nrofSRS-Ports'. When the upper layer in which the terminal is configured with the parameter 'txConfig' is set to 'codebook', at least one SRS resource is configured for the terminal. The SRI indicated in slot n is associated with the most recent transmission of the SRS resource identified by the SRI, where the SRS resource precedes the PDCCH carrying the SRI (i.e., slot n).

[0264] The operations based on the above-described S310 to S320, DCI reception step, and PUSCH transmission step can be implemented by the device of FIG. 5. For example, the terminal (200) can control one or more transceivers (230) and / or one or more memories (240) to perform operations based on S310 to S320, DCI reception step, and PUSCH transmission step.

[0265] The embodiments described below are specifically described in terms of base station operation.

[0266] The S410 to S420, DCI transmission step and PUSCH reception step described below correspond to the S310 to S320, DCI reception step and PUSCH transmission step described in FIG. 3. Considering the above correspondence relationship, redundant descriptions are omitted. That is, the specific description of the base station operation described below can be replaced with the description / example of FIG. 3 corresponding to the corresponding operation.

[0267] For example, the description / example of S310 to S320 of FIG. 3 may be additionally applied to the base station operations of S410 to S420 described below. For example, the description / example of the DCI reception step and the PUSCH transmission step described above may be additionally applied to the base station operations according to the DCI transmission step and the PUSCH reception step described below.

[0268] FIG. 4 is a flowchart illustrating a method according to another embodiment of the present specification.

[0269] Referring to FIG. 4, a method according to another embodiment of the present specification includes a step of transmitting settings related to SRS (S410) and a step of receiving SRS based on SRS resources (S420).

[0270] In S410, the base station transmits configuration information including configuration for Sounding Reference Signal (SRS) resources to the terminal.

[0271] In S420, the base station receives an SRS from the terminal based on the SRS resource.

[0272] In one embodiment, the method may further include a DCI transmission step and a PUSCH reception step.

[0273] In the DCI transmission phase, the base station transmits downlink control information (DCI) for scheduling the physical uplink shared channel (PUSCH) to the terminal.

[0274] In the PUSCH reception step, the base station receives the PUSCH from the terminal based on the DCI.

[0275] The operations based on the above-described S410 to S420, DCI transmission step and PUSCH reception step can be implemented by the device of FIG. 5. For example, the base station (100) can control one or more transceivers (130) and / or one or more memories (140) to perform the operations based on S410 to S420, DCI transmission step and PUSCH reception step.

[0276] Hereinafter, a device to which an embodiment of the present specification can be applied (a device that implements a method / operation according to an embodiment of the present specification) is described with reference to FIG. 5.

[0277] FIG. 5 is a drawing showing the configuration of a first device and a second device according to an embodiment of the present specification.

[0278] The first device (100) may include a processor (110), an antenna unit (120), a transceiver (130), and a memory (140).

[0279] The processor (110) performs baseband-related signal processing and may include a higher layer processing unit (111) and a physical layer processing unit (115). The higher layer processing unit (111) may process operations of a MAC layer, an RRC layer, or higher layers. The physical layer processing unit (115) may process operations of a PHY layer. For example, when the first device (100) is a base station device in base station-terminal communication, the physical layer processing unit (115) may perform uplink reception signal processing, downlink transmission signal processing, etc. For example, when the first device (100) is a first terminal device in terminal-to-terminal communication, the physical layer processing unit (115) may perform downlink reception signal processing, uplink transmission signal processing, sidelink transmission signal processing, etc. In addition to performing baseband-related signal processing, the processor (110) may also control the overall operation of the first device (100).

[0280] The antenna unit (120) may include one or more physical antennas, and when it includes multiple antennas, it may support MIMO transmission and reception. The transceiver (130) may include an RF (Radio Frequency) transmitter and an RF receiver. The memory (140) may store information processed by the processor (110), and software, an operating system, applications, etc. related to the operation of the first device (100), and may also include components such as a buffer.

[0281] The processor (110) of the first device (100) may be configured to implement the operation of the base station in the base station-to-terminal communication (or the operation of the first terminal device in the terminal-to-terminal communication) in the embodiments described in the present disclosure.

[0282] The second device (200) may include a processor (210), an antenna unit (220), a transceiver (230), and a memory (240).

[0283] The processor (210) performs baseband-related signal processing and may include a higher layer processing unit (211) and a physical layer processing unit (215). The higher layer processing unit (211) may process operations of a MAC layer, an RRC layer, or higher layers. The physical layer processing unit (215) may process operations of a PHY layer. For example, when the second device (200) is a terminal device in base station-terminal communication, the physical layer processing unit (215) may perform downlink reception signal processing, uplink transmission signal processing, etc. For example, when the second device (200) is a second terminal device in terminal-to-terminal communication, the physical layer processing unit (215) may perform downlink reception signal processing, uplink transmission signal processing, sidelink reception signal processing, etc. In addition to performing baseband-related signal processing, the processor (210) may also control the overall operation of the second device (210).

[0284] The antenna unit (220) may include one or more physical antennas, and when it includes multiple antennas, it may support MIMO transmission and reception. The transceiver (230) may include an RF transmitter and an RF receiver. The memory (240) may store information processed by the processor (210), software, an operating system, applications, etc. related to the operation of the second device (200), and may also include components such as a buffer.

[0285] The processor (210) of the second device (200) may be configured to implement operations of the terminal in base station-to-terminal communication (or operations of the second terminal device in terminal-to-terminal communication) in the embodiments described in the present disclosure.

[0286] In the operation of the first device (100) and the second device (200), the same explanations given for the base station and the terminal (or the first terminal and the second terminal in the terminal-to-terminal communication) in the examples of the present disclosure may be applied, and redundant explanations are omitted.

[0287] Here, the wireless communication technology implemented in the device (100, 200) of the present disclosure may include not only LTE, NR, and 6G, but also Narrowband Internet of Things (NB-IoT) for low-power communication. For example, NB-IoT technology may be an example of LPWAN (Low Power Wide Area Network) technology, and may be implemented in standards such as LTE Cat NB1 and / or LTE Cat NB2, and is not limited to the above-described names.

[0288] Additionally or alternatively, the wireless communication technology implemented in the device (100, 200) of the present disclosure may perform communication based on LTE-M technology. For example, LTE-M technology may be an example of LPWAN technology and may be called by various names such as eMTC (enhanced Machine Type Communication). For example, LTE-M technology may be implemented by at least one of various standards such as 1) LTE CAT 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-BL (non-Bandwidth Limited), 5) LTE-MTC, 6) LTE Machine Type Communication, and / or 7) LTE M, and is not limited to the above-described names.

[0289] Additionally or alternatively, the wireless communication technology implemented in the device (100, 200) of the present disclosure may include at least one of ZigBee, Bluetooth, and Low Power Wide Area Network (LPWAN) that take low-power communication into account, and is not limited to the above-described names. For example, ZigBee technology can create personal area networks (PANs) related to small / low-power digital communication based on various standards such as IEEE 802.15.4, and may be called by various names.

Claims

1. In terms of method, A step of receiving configuration information including configuration for a Sounding Reference Signal (SRS) resource from a base station; and A step of transmitting SRS to the base station based on the SRS resource; Including, The number of ports set in the above SRS resource is 4. A method characterized in that the SRS is transmitted based on three of four ports based on i) the configuration information, ii) downlink control information (DCI) related to the SRS, and / or iii) MAC CE (Medium Access Control Control Element) related to the SRS.

2. In paragraph 1, Frequency domain resources associated with the four ports are determined based on the transmission comb number associated with the above SRS resource, A method characterized in that the above SRS is transmitted based on frequency domain resources associated with the three ports.

3. In paragraph 2, A method characterized in that the above three ports are determined in ascending order of port index.

4. In paragraph 2, A method characterized in that the above three ports are determined based on the above setting information, the DCI or the MAC CE.

5. In paragraph 1, A method characterized in that three of the four ports are enabled based on the above setting information, the DCI or the MAC CE.

6. In paragraph 1, A method characterized in that, based on the above setting information, the DCI or the MAC CE, the remaining ports except for the three ports among the four ports are disabled.

7. In paragraph 1, The cyclic shifts associated with each of the four ports are determined based on the maximum number of cyclic shifts, A method characterized in that the sequence associated with the above SRS resource is generated based on cyclic shifts associated with the above three ports.

8. In paragraph 7, A method characterized in that the above three ports are determined in ascending order of port index.

9. In paragraph 7, A method characterized in that the above three ports are determined based on the above setting information, the DCI or the MAC CE.

10. In paragraph 7, A method characterized in that the value for determining the cyclic shift for each port is determined based on the product of the maximum number and the index of each port, based on the above maximum number being a multiple of 3.

11. In paragraph 7, A method characterized in that the value for determining the cyclic shift for each port is determined based on the product of the number of ports and the index of each port, based on the fact that the maximum number is a value other than a multiple of 3.

12. In paragraph 1, The above SRS is transmitted based on the first frequency domain resources and the second frequency domain resources, The above first frequency domain resource is associated with two first ports among the above three ports, A method characterized in that the second frequency domain resource is related to a second port among the three ports.

13. In paragraph 12, A method characterized in that the first transmission power associated with each of the two first ports and the second transmission power associated with the second port are equal.

14. In paragraph 13, A method characterized in that a power boosting factor associated with the second port is different from a power boosting factor associated with each of the two first ports.

15. In paragraph 12, A method characterized in that the two first ports and the second port are determined based on a rule.

16. In paragraph 12, A method characterized in that the two first ports and the second port are determined based on the setting information, the DCI or the MAC CE.

17. In paragraph 1, A method characterized in that the above three ports are ports 1000, 1001, and 1002.

18. In paragraph 1, A method characterized in that the DCI includes an SRS request field related to a trigger of the SRS.

19. In paragraph 1, A method characterized in that the above MAC CE is related to the activation of the SRS.

20. At the terminal, One or more transmitters and receivers; one or more processors; and comprising one or more memories connected to said one or more processors and storing instructions; A terminal characterized in that said instructions, based on being executed by said one or more processors, cause said terminal to perform all steps of a method according to any one of claims 1 to 19.

21. In a device comprising one or more memories and one or more processors connected to the one or more memories, A device characterized in that said one or more memories store instructions that cause said device to perform all steps of a method according to any one of claims 1 to 19, based on execution by said one or more processors.

22. In one or more non-transitory computer-readable storage media storing instructions, One or more non-transitory computer-readable storage media characterized in that the instructions executable by one or more processors cause a terminal to perform all steps of a method according to any one of claims 1 to 19.

23. In the method, A step of transmitting configuration information including configuration for a Sounding Reference Signal (SRS) resource to a terminal; and A step of receiving an SRS from the terminal based on the SRS resource; Including, The number of ports set in the above SRS resource is 4. A method characterized in that the SRS is transmitted based on three of four ports based on i) the configuration information, ii) downlink control information (DCI) related to the SRS, and / or iii) MAC CE (Medium Access Control Control Element) related to the SRS.

24. At the base station, One or more transmitters and receivers; one or more processors; and comprising one or more memories connected to said one or more processors and storing instructions; A base station characterized in that said instructions, based on being executed by said one or more processors, cause said base station to perform all steps of the method according to claim 23.

Images