KR20230059733A - Enhancements to support hst-sfn deployment scenario - Google Patents

Abstract

A method for determining a default transmission configuration indicator (TCI) state for a user equipment (UE) in a wireless communication network includes, by the UE, determining that wireless communication is performed in frequency range 2 (FR2), by the UE, DCI Receiving one or more control resource sets (CORESETs) carrying a physical downlink control channel (PDCCH) having downlink control information (PDCCH), by the UE, DCI and receptions by the UE of the corresponding physical downlink shared channel (PDSCH) Determining, by the UE, that the PDSCH is configured in a single frequency network (SFN) manner; Determining, by the UE, that the option to activate the two default TCI states for the UE is not configured determining, by the UE, whether the PDCCH is configured in the SFN scheme; determining, by the UE, a default TCI state for PDSCH reception based on whether the PDCCH is configured in the SFN scheme; and receiving the PDSCH using the determined default TCI state.

Description

ENHANCEMENTS TO SUPPORT HST-SFN DEPLOYMENT SCENARIO}

The technical idea of the present disclosure relates to a wireless communication system, and more specifically, to a system and method for high-speed trains (HST)-single-frequency network (SFN) transmission.

This disclosure is based on U.S. Provisional Application No. 63/090,175, filed on October 9, 2020, U.S. Provisional Application No. 63/130,405, filed on December 23, 2020, and U.S. Provisional Application No. 63/159,443, filed on March 10, 2021. , US Provisional Application No. 63/164,807, filed March 23, 2021, incorporated by reference in its entirety.

In current high-speed train (HST) scenarios with a single-frequency network (SFN), dynamic switching between transmit and receive points (TRPs) is the only way for SFN transmission to derive quasi co-located (QCL) properties. Additional tracking reference signal (TRS) and channel state information-reference signal (CSI-RS) resources may be required, and high overhead of resource configuration may be used. In addition, in HST scenarios with current SFN transmission, the TRS and corresponding demodulation reference signal (DMRS) ports are used for the major path from each TRP, which may require very high user equipment (UE) complexity. You can experience a composite channel. Furthermore, the high mobility of the UE in the HST environment may cause a negative Doppler offset moving away from one TRP and a positive Doppler offset moving towards the other TRP, and each TRP uses independent local oscillators so that the Doppler offsets are different. may be based on base frequencies. Thus, in the HST-FSN scenario, the UE may require very high complexity to accurately estimate the significantly difficult and different Doppler shifts based on the complex TRS, resulting in estimated Doppler to improve the channel estimation performance. You can use a Wiener filter for shifts.

The technical idea of the present disclosure may provide improvements for support of HST-SFN deployment scenarios.

According to one aspect of the technical idea of the present disclosure, a method for determining a default transmission configuration indicator (TCI) state for a user equipment (UE) in a wireless communication network, by the UE, wireless communication is performed in frequency range 2 (FR2) determining that it is performed, receiving, by the UE, one or more control resource sets (CORESETs) carrying a physical downlink control channel (PDCCH) having downlink control information (DCI); and, by the UE, DCI and the corresponding PDSCH ( determining, by the UE, the PDSCH is configured in a single frequency network (SFN) fashion; Determining that the option to activate states is not configured, determining, by the UE, whether the PDCCH is configured in SFN mode, and determining, by the UE, whether the PDCCH is configured in SFN mode for PDSCH reception. Determining a default TCI state, and receiving, by a UE, a PDSCH using the determined default TCI state.

According to an exemplary embodiment of the present disclosure, when the UE determines that the PDCCH is configured in the SFN scheme, the default TCI state for PDSCH reception may be determined based on one or more CORESETs with a single TCI state.

According to an exemplary embodiment of the present disclosure, when the UE determines that the PDCCH is not configured in an SFN manner, a default TCI state for PDSCH reception may be determined based on a reference TCI state selected from TCI states of one or more CORESETs. can

According to an exemplary embodiment of the present disclosure, when the UE determines that the PDCCH is not configured in an SFN manner, the default TCI state for PDSCH reception may be determined based on the TCI state of the CORESET with the lowest CORESET indicator.

According to an exemplary embodiment of the present disclosure, the time offset between receptions by the UE of the DCI and the corresponding PDSCH is the spatial quasi-colocation (QCL) received at the DCI for the UE to perform PDCCH reception and for PDSCH processing. It may be shorter than the time duration for the minimum number of orthogonal frequency-division multiplexed (OFDM) symbols for applying the information.

According to one aspect of the technical idea of the present disclosure, a method for determining a default transmission configuration indicator (TCI) state for a user equipment (UE) in a wireless communication network, by the UE, wireless communication is performed in frequency range 2 (FR2) determining that it is performed, receiving, by the UE, one or more CORESETs comprising a scheduling control resource set (CORESET) carrying a physical downlink control channel (PDCCH) having downlink control information (DCI); Determining that the time offset between receptions by the UE of the DCI and the corresponding physical downlink shared channel (PDSCH) is greater than or equal to a predetermined time threshold; Determining, by the UE, that the TCI state does not exist in the DCI; determining whether the PDSCH is configured in a single frequency network (SFN) scheme by the UE, determining whether the PDCCH is configured in the SFN scheme by the UE, whether the PDSCH is configured in the SFN scheme by the UE, and Based on whether the PDCCH is configured in the SFN scheme, determining a default TCI state for PDSCH reception, and receiving, by the UE, the PDSCH using the determined default TCI state.

According to an exemplary embodiment of the present disclosure, the method may further include determining, by the UE, that two default TCI states are configurable for the UE, wherein the PDSCH is configured in an SFN scheme and the PDCCH is If it is determined that it is configured in the SFN scheme, it may be determined that the default TCI state for PDSCH reception includes two TCI states of scheduling CORESET.

According to an exemplary embodiment of the present disclosure, the method may further include determining, by the UE, that only one default TCI state is configurable for the UE, wherein the PDSCH is configured in an SFN manner and the PDCCH If it is determined that is configured in the SFN scheme, the default TCI state for PDSCH reception may be determined based on one TCI state of scheduling CORESET.

According to an exemplary embodiment of the present disclosure, one TCI state of scheduling CORESET may be predetermined or semi-statically indicated to the UE as a reference TCI state to be used to determine a default TCI state for PDSCH reception. there is.

According to an exemplary embodiment of the present disclosure, when the UE determines that the PDSCH is configured in the SFN scheme and the PDCCH is not configured in the SFN scheme, the default TCI state for PDSCH reception determines the default TCI state for PDSCH reception. It may be determined based on the TCI state of the scheduling CORESET, which is predetermined or semi-statically indicated to the UE as the reference TCI state to be used.

According to an exemplary embodiment of the present disclosure, when the UE determines that the PDSCH is not configured in the SFN scheme and the PDCCH is configured in the SFN scheme, the default TCI state for PDSCH reception determines the default TCI state for PDSCH reception. It can be determined based on the TCI state of the scheduling CORESET that is predetermined or semi-statically indicated to the UE as the reference TCI state to be used.

According to an exemplary embodiment of the present disclosure, when the UE determines that the PDSCH is not configured in the SFN scheme and the PDCCH is not configured in the SFN scheme, the default TCI state for PDSCH reception has the lowest controlResourceSetId in the latest slot. It can be determined that the active TCI state of CORESET.

According to one aspect of the technical idea of the present disclosure, a method for determining a default transmission configuration indicator (TCI) state for a user equipment (UE) in a wireless communication network, by the UE, wireless communication is performed in a frequency range 1 (FR1) determining, by the UE, one or more CORESETs comprising scheduling CORESETs carrying a physical downlink control channel (PDCCH) having downlink control information (DCI); receiving, by the UE, TCI status in the DCI; Determining non-existence, determining, by the UE, whether a physical downlink shared channel (PDSCH) is configured in a single frequency network (SFN) scheme; determining, by the UE, whether the PDCCH is configured in the SFN scheme determining, by the UE, a default TCI state for PDSCH reception based on whether the PDSCH is configured in the SFN scheme and based on whether the PDCCH is configured in the SFN scheme, and by the UE, the determined default TCI state It may include receiving the PDSCH using.

According to an exemplary embodiment of the present disclosure, when the UE determines that the PDSCH is configured in the SFN scheme and the PDCCH is configured in the SFN scheme, the default TCI state for PDSCH reception is to include two TCI states of scheduling CORESET. can be judged.

According to an exemplary embodiment of the present disclosure, when the UE determines that the PDSCH is not configured in the SFN scheme and the PDCCH is configured in the SFN scheme, the default TCI state for PDSCH reception is based on one TCI state of the scheduling CORESET can be judged.

According to an exemplary embodiment of the present disclosure, one TCI state of the scheduling CORESET may be predetermined or semi-statically indicated to the UE as a reference TCI state to be used to determine a default TCI state for PDSCH reception.

According to an exemplary embodiment of the present disclosure, when the UE determines that the PDSCH is not configured in the SFN scheme and the PDCCH is not configured in the SFN scheme, the default TCI state for PDSCH reception has the lowest controlResourceSetId in the latest slot. It can be determined that the active TCI state of CORESET.

1 illustrates a wireless communication network according to an exemplary embodiment of the present disclosure.
2 illustrates a base station according to an exemplary embodiment of the present disclosure.
Fig. 3 shows a user equipment according to an exemplary embodiment of the present disclosure.
4A shows an example of a downlink slot structure.
4B shows an example of an uplink slot structure for PUSCH transmission or PUCCH transmission.
5A is a block diagram illustrating a transmitter structure using OFDM according to an exemplary embodiment of the present disclosure.
5B is a block diagram illustrating an OFDM receiver structure according to an exemplary embodiment of the present disclosure.
6 shows an example of an HST-SFN environment in which coherent joint transmission can occur.
7 shows an example of RS overhead in an example bandwidth for configuration of a QCL reference RS in an SFN transmission for three TRPs.
Figure 8 shows separate QCL RSs for three TRPs sufficient for dynamic switching among the three TRPs.
9A-9C show three dynamic switching scenarios respectively in an exemplary HST-SFN environment including a first TRP, a second TRP and a UE.
10A to 10C are first embodiment of a first embodiment in which a predetermined TRP known to the UE is a constant reference for frequency-offset pre-compensation at the gNB side for all dynamic-switching transmission cases according to exemplary embodiments of the present disclosure; represents the side.
11A to 11C are second embodiments of the first embodiment in which a predetermined TRP known to the UE is a constant reference for frequency-offset pre-compensation at the gNB side for all dynamic-switching transmission cases according to exemplary embodiments of the present disclosure; represents the side.
12A-12C respectively show frequency-offset compensation schemes for three dynamic-switching cases in which each TRP is responsible for its corresponding frequency-offset precompensation according to an exemplary embodiment of the present disclosure.
13 illustrates a fourth aspect of the first embodiment for network frequency-offset precompensation using a three-step method with implicit UE indication according to an exemplary embodiment of the present disclosure.
14 illustrates a fifth aspect of the first embodiment for network frequency-offset precompensation using a two-step method starting with UL RS transmission according to an exemplary embodiment of the present disclosure.
15A and 15B are exemplary embodiments of a three-step method and a two-step method for network-offset precompensation that provide TRP-specific frequency offset precompensation independently for each TRP according to an exemplary embodiment of the present disclosure. represent each.
16A and 16B show a second series example of a three-step method and a two-step method for network frequency-offset precompensation using SFN-mode TRS transmission with implicit UE indication according to exemplary embodiments of the present disclosure. represent each.
17A and 17B illustrate example embodiments of a three-step method and a two-step method using SFN-style TRS transmission with independently provided network precompensation for each TRP according to an example embodiment of the present disclosure. represent each.
18 illustrates another aspect of a second embodiment combining SFN and TRP-specific TRS transmission for a three-phase method according to an exemplary embodiment of the present disclosure.
19 illustrates another aspect of a second embodiment combining SFN and TRP-specific TRS transmissions with network precompensation of Doppler shift provided independently for each TRP according to an exemplary embodiment of the present disclosure.
20 illustrates a QCL relationship of a TRS reference signal for semi-persistent resources that may be configured through a medium access control (MAC) control element (CE) triggering process according to an exemplary embodiment of the present disclosure.
21 shows reuse of the Rel-17 Advanced TCI States Activation/Deactivation MAC CE structure.
22 is a block diagram illustrating an example of a UE receiver for demodulating and decoding received data.
23 is a block diagram illustrating a UE receiver according to an exemplary embodiment of the present disclosure.
24 is a block diagram illustrating a UE receiver with split receiver chains according to an exemplary embodiment of the present disclosure.
25 and 26 respectively illustrate single-DCI and multi-DCI M-TRP transmission schemes according to exemplary embodiments of the present disclosure.
27A illustrates how one PDCCH candidate (in a given set of SSs) can be associated with both TCI states of a CORESET according to an exemplary embodiment of the present disclosure.
27B shows how two sets of PDCCH candidates (in a given SS set) are associated with two TCI states of CORESET, respectively, according to an exemplary embodiment of the present disclosure.
27C shows that two sets of PDCCH candidates (in a given SS set) are associated with CORESET, and each SS set is associated with only one TCI state of CORESET, according to an exemplary embodiment of the present disclosure. Indicates how to associate with two corresponding SS sets, which can be
28A-28D show repetition schemes according to an exemplary embodiment of the present disclosure.
29 shows an example of PDSCH scheduling and UE operation according to method 10.
30 illustrates method 11 according to an exemplary embodiment of the present disclosure.
31 illustrates method 12 according to an exemplary embodiment of the present disclosure.
32 illustrates method 13 according to an exemplary embodiment of the present disclosure.
33 illustrates intra-slot TDM according to an exemplary embodiment of the present disclosure.
34 illustrates multiple contiguous chunks with alternating TCI states with L=2 according to an exemplary embodiment of the present disclosure.
35 illustrates multiple consecutive slots with alternating TCI states based on inter-slot TDM case 2 according to an exemplary embodiment of the present disclosure.
36 illustrates an FDM PDSCH scheme according to an exemplary embodiment of the present disclosure.
37 is a flow chart illustrating a method for determining a default TCI state for a UE in a wireless communication network according to an exemplary embodiment of the present disclosure.
38 is a flow chart illustrating a method for determining a default TCI state for a UE in a wireless communication network according to an exemplary embodiment of the present disclosure.
39 is a flow chart illustrating a method for determining a default state for a UE in a wireless communication network according to an exemplary embodiment of the present disclosure.

In the following, numerous specific details are set forth to provide a thorough understanding of the present disclosure. However, it will be understood by those skilled in the art that the disclosed aspects may be practiced without these specific details. In other instances, known methods, procedures, components and circuits have not been described in detail in order not to obscure the subject matter disclosed herein.

Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment disclosed herein. do. Thus, the appearances of the terms “in one embodiment” or “according to an embodiment” (or other phrases having a similar meaning) in various places throughout this specification are not necessarily all referring to the same embodiment. In addition, certain features, structures or characteristics may be combined in any suitable way in one or more embodiments. In this regard, as used herein, the word "exemplary" means "serving as an example, instance, or illustration." Any embodiment described herein as "exemplary" should not be construed as necessarily preferred or advantageous over other embodiments. Additionally, certain features, structures, or characteristics may be combined in any suitable way in one or more embodiments. Also, according to the subject matter discussed herein, a singular term may include a corresponding plural form, and a plural term may include a corresponding singular form. Similarly, a hyphenated term (e.g. "two-dimensional", "predetermined", "pixel-specific", etc.) may have its non-hyphenated version (e.g. "two-dimensional", "predetermined", "pixel-specific", etc.) "specific", etc.), and capitalized items can sometimes be used interchangeably with their non-capitalized versions. These intermittent compatible uses are not to be regarded as inconsistent.

Also, according to the context of the description herein, a singular term may include a corresponding plural form, and a plural term may include a corresponding singular form. It is noted that the various drawings (including block diagrams) shown and discussed herein are for illustrative purposes only and are not drawn to scale. For example, the dimensions of some components may be exaggerated relative to others for clarity. Also, where deemed appropriate, reference numbers are repeated between the drawings to indicate corresponding and/or like elements.

The terminology used herein is merely for describing some exemplary embodiments and is not intended to limit the claimed technical idea. As used herein, the singular forms are intended to include the plural forms as well, unless the context clearly dictates otherwise. As used herein, the terms "comprise" and/or "comprising" specify the presence of specified features, integers, steps, operations, elements and/or components, but not one or more other features, integers, steps, operations. However, it will also be understood that does not exclude the presence or addition of elements, components and/or groups thereof.

When an element or layer is referred to as "connected" or "coupled" to another element or layer, it may be directly, connected or coupled to the other element or layer, or to an intermediate element or layer. may exist. In contrast, when an element is referred to as “directly,” “directly connected to,” or “directly coupled to” another element or layer, intermediate elements or layers may not be present. Like numbers indicate like elements throughout. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

As used herein, the terms "first", "second", etc. are used as labels for the preceding noun and do not imply any type of order (eg, spatial, temporal, logical, etc.) unless explicitly defined. No. Also, the same reference number may be used in more than one drawing to refer to parts, components, blocks, circuits, units or modules having the same or similar function. However, this use is for simplicity of explanation and convenience of explanation. It is not meant that configurations or architectural details of such components or units are the same across all embodiments, or that such commonly referenced parts/modules are the only methods of implementing some of the exemplary embodiments disclosed herein.

Unless otherwise defined, all terms (including technical and scientific terms) used in this specification have the same meaning as commonly understood by a person of ordinary skill in the art to which this technical idea belongs. Terms such as those defined in commonly used dictionaries are to be construed to have a meaning consistent with the meaning in the context of the relevant art and, unless interpreted in an idealized or overly formal sense, are as expressly defined herein.

As used herein, the term "module" refers to any combination of software, firmware, and/or hardware configured to provide the functionality described herein with respect to a module. For example, software may be implemented as a software package, code and/or set of instructions or instructions, and the term "hardware" used in any implementation described herein includes, for example, assembly, hardwired circuitry, programmable circuitry, state machine circuitry, and/or firmware that stores instructions executed by programmable circuitry. Modules, either collectively or individually, may be embedded as circuits that form part of a larger system, such as an integrated circuit (IC), system on a chip (SoC), assembly, or the like.

1 to 39 described below and various embodiments used to illustrate the technical idea disclosed herein are only examples, and should not be construed as limiting the scope of the technical idea disclosed herein in any way. do. It should be understood that the technical ideas disclosed herein may be implemented in any appropriately arranged system or device.

At least the following documents are incorporated by reference into this disclosure as if fully set forth herein: 3GPP TS 38.211 v15.6.0, “NR; Physical channels and modulation”, 3GPP TS 38.212 v15.6.0, “NR; /multiplexing and Channel coding ", 3GPP TS 38.213 v15.6.0, "NR; Physical Layer Procedures for Control", 3GPP TS 38.214 v15.6.0, "NR; Physical Layer Procedures for Data", 3GPP TS 38.321 v15.6.0, "NR; Medium Access Control ( MAC) protocol specification", and 3GPP TS 38.331 v15.6.0, "NR; Radio Resource Control (RRC) Protocol Specification".

1-5 illustrate various exemplary embodiments implemented in wireless communication systems using orthogonal frequency division multiplexing (OFDM) or orthogonal frequency division multiple access (OFDMA) communication techniques. The descriptions of FIGS. 1-5 do not imply physical or structural limitations on the manner in which different embodiments may be implemented. Different embodiments of the technical concepts disclosed herein may be implemented in any suitably arranged communication system.

1 illustrates a wireless communications network 100 according to an exemplary embodiment of the present disclosure. The wireless network shown in FIG. 1 is exemplary only. Other examples of wireless network 100 may be used without departing from the scope of the present disclosure.

As shown in FIG. 1 , a wireless network 100 may include a gNB 101 (eg, a base station (BS)), a gNB 102 and a gNB 103 . gNB 101 can communicate with gNB 102 and gNB 103 . The gNB 101 may communicate with at least one network 130 , such as the Internet, a proprietary internet protocol (IP) network, or another network.

The gNB 102 may provide wireless wide area access to the network 130 for a first plurality of UEs within coverage of the gNB 102 . The plurality of first UEs include a UE 111 that can be located in a small business (SB), a UE 112 that can be located in an enterprise, a UE 113 that can be located in a WiFi hotspot (HS), and a first residence UE 114, which may be located in a second residence, UE 115, which may be located in a second residence, and UE 116, which may be a mobile device (M) such as, but not limited to, a cell phone, wireless laptop, wireless PDA, etc. ) may be included. The gNB 103 may provide wireless wide area access to the network 130 for a plurality of secondary UEs within the coverage area 125 of the gNB 103 . The plurality of second UEs may include UE 115 and UE 116 . In some embodiments, one or more of the gNBs 101 - 103 communicate with each other using 5G/NR, LTE, LTE-A, WiMAX, WiFi and/or other wireless communication technologies, and/or UEs. Can communicate with (111 to 116).

Depending on the network type, a “base station” or “BS” can be a transmit point (TP), transmit-receive point (TPR), eNodeB or enhanced base station (eNB), 5g/NR base station (gNB), micro It may refer to any component configured to provide wireless access to a network, such as a cell, femtocell, WiFi access point (AP), or other wirelessly enabled devices. Base stations, for example, 5G / NR 3GPP new radio interface / access (NR), long term evolution (LTE), LTE-advanced (LTE-A), high speed packet access (HSPA), WiFi 802.11a / b / g / Wireless access may be provided according to one or more wireless communication protocols, such as n/ac. For convenience, “BS” and “TRP” are used interchangeably herein to refer to network infrastructure components that provide wireless access to remote terminals. Also, depending on the type of network, "user equipment" or "UE" may mean "mobile station", "subscriber station", "remote terminal", "wireless terminal", "receiving point" or "receive point". user device". For convenience, “user equipment” and “UE” refer to whether a UE is generally considered a mobile device (as a non-limiting example, a mobile phone or smartphone) or a fixed device (as a non-limiting example, a desktop computer or vending machine). Regardless, may be used herein to refer to a remote wireless device wirelessly accessing a BS.

Dotted lines indicate approximate extents of coverage areas 120 and 125 and are drawn circular for purposes of illustration and explanation. Coverage areas associated with gNBs, such as coverage areas 120 and 125, may have different shapes, including irregular shapes, depending on the configuration of the gNBs and variations in the wireless environment associated with natural and man-made obstacles.

As discussed below, one or more of the UEs 111 - 116 may include circuitry, programming or a combination thereof for efficient control signaling designed for improved resource utilization. In present embodiments, one or more of the gNBs 101 - 103 may include circuitry, programming, or a combination thereof for efficient control signaling designed for improved resource utilization.

Although FIG. 1 illustrates an example of a wireless network, various changes may be made to FIG. 1 . For example, wireless network 100 may include any number of gNBs and any number of UEs, arbitrarily and suitably placed. In addition, gNB 101 may communicate directly with any number of UEs and may provide wireless wide area access to network 130 to those UEs. Similarly, each of gNBs 102 and 103 may communicate directly with network 130 and provide direct wireless wide area access to network 130 to UEs. Additionally, gNBs 101 , 102 and/or 103 may provide access to other or additional external networks, such as external telephone networks or other types of data networks, as a non-limiting example.

2 shows an example of a gNB 102 according to an exemplary embodiment of the present disclosure. The gNB 102 shown in FIG. 2 is just an example, and the gNBs 101 and 103 in FIG. 1 may have the same or similar configuration. However, it should be understood that gNBs can be provided in a wide variety of configurations, and FIG. 2 is not intended to limit the scope of the ideas disclosed herein to any particular implementation of a gNB.

As shown in FIG. 2, the gNB 102 includes multiple antennas 201a to 201n, multiple radio frequency (RF) transceivers 202a to 202n, receive (RX) processing circuitry 203 and transmit ( TX) processing circuitry 204 . The gNB 102 may also include a controller/processor 205 , memory 206 and/or a backhaul or network interface 207 . The TX processing circuitry 204 may include a controller/processor, not shown, that controls the TX processing circuitry 204 to perform functions related to transmission as described herein. Alternatively, the controller/processor 205 may be configured to control the TX processing circuitry 204 to perform functions related to transmission as disclosed herein.

RF transceivers 202a through 202n may receive incoming RF signals from antennas 201a through 201n. Received RF signals may be signals transmitted by UEs in network 100 . The RF transceivers 202a through 202n may down-convert incoming RF signals to generate intermediate frequency (IF) or baseband signals. The IF or baseband signals may be sent to RX processing circuitry 203 which generates processed baseband signals by filtering, decoding and/or digitizing the baseband or IF signals.

TX processing circuitry 204 may receive analog or digital data (as non-limiting examples of voice data, web data, e-mail or interactive video game data) from controller/processor 225 . TX processing circuitry 204 may encode, multiplex, and/or digitize outgoing baseband data to generate processed baseband or IF signals. The RF transceivers 202a to 202n may receive the outgoing processed baseband or IF signals from the TX processing circuitry 204, and transmit the baseband or IF signals to the RF signal to be transmitted through the antennas 201a to 201n. can be up-converted to . TX processing circuitry 204 may be configured to transmit one or more beams to be transmitted via antennas 201a through 201n.

The controller/processor 205 may include one or more processors or other processing devices capable of controlling the overall operation of the gNB 102 . For example, the controller/processor 205 may perform reception of forward channel signals by RF transceivers 202a to 202n, RX processing circuitry 203 and TX processing circuitry 204, according to known principles. and control transmission of reverse channel signals. The controller/processor 205 may support additional functions, such as more advanced wireless communication functions, for example. For example, the controller/processor 205 may allow outgoing/incoming signals via multiple antennas 201a to 201n to be weighted differently to effectively steer the outgoing signals in a desired direction. Beamforming or directional-routing operations may be supported. Any of a variety of other functions may be supported in the gNB 102 by the controller/processor 205 .

Controller/processor 205, like an operating system (OS), may execute programs and other processes stored in memory 206. Controller/processor 205 may move data to or from memory 206 , which may be coupled to controller/processor 205 , depending on the needs of the running process. Part of memory 206 may include random access memory (RAM), and another part of memory 206 may include flash memory or other read only memory (ROM).

The controller/processor 205 may also be coupled to a backhaul or network interface 207 . The backhaul or network interface 207 may allow the gNB 102 to communicate with other devices or systems over a backhaul connection or network. Backhaul or network interface 207 may support communications over any suitable wired or wireless connection(s). For example, gNB 102 can be implemented as part of a cellular communication system (eg, a gNB supporting 5G/NR, LTE or LTE-A), and backhaul or network interface 207 to gNB 102. to communicate with other gNBs via a wired or wireless backhaul connection. When the gNB 102 is implemented as an access point, the backhaul or network interface 207 allows the gNB 102 to connect via a wired or local area network (LAN) or to a larger network (e.g., the Internet). You can communicate through a connection. Backhaul or network interface 207 may include any suitable structure that supports communications over a wired or wireless connection, such as an Ethernet or RF transceiver.

Although FIG. 2 shows an example of gNB 102 , various changes may be made to FIG. 2 . For example, gNB 102 may include any number of each of the components shown in FIG. 2 . As an example, an access point may include multiple backhaul or network interfaces, and the controller/processor 205 may support routing functions to route data between different network addresses. As another example, although shown as including one TX processing circuit 204 and one RX processing circuit 203, the gNB 102 may include multiples of each of the foregoing (e.g., per RF transceiver). there is. Also, various components of FIG. 2 may be combined, further divided, or omitted, and additional components may be added according to particular needs. The exemplary gNB 102 shown in FIG. 2 may be configured to provide some or all of the functions of a base station device and/or gNB described herein.

3 illustrates a UE 116 according to an exemplary embodiment of the present disclosure. The UE 116 shown in FIG. 3 is just an example, and the UEs 111 to 115 in FIG. 1 may have the same or similar configuration. However, UEs may be provided in a variety of configurations, and FIG. 3 does not limit the UE to any particular implementation of the UE.

As shown in FIG. 3 , UE 116 may include one or more antenna 301 , RF transceiver 302 , TX processing circuitry 303 , microphone 304 and RX processing circuitry 305 . UE 116 also includes a speaker 360, processor 307, input/output (I/O) interface 308, touchscreen 309 (or other input device), display 310, and memory 311. can include The memory 311 may include an OS 312 and one or more applications 313 . TX processing circuitry 303 may include a controller/processor, not shown, that may be configured to control TX processing circuitry 303 to perform functions related to transmission as disclosed herein. Alternatively, processor 307 may be configured to control TX processing circuitry 303 to perform functions related to transmission as described herein.

The RF transceiver 302 may receive an incoming RF signal transmitted by the gNB of the network 100 from the antenna. The RF transceiver 302 may downconvert an incoming RF signal to generate an IF or baseband signal. The IF or baseband signal may be sent to RX processing circuitry 305, which may filter, decode, and/or digitize the baseband or IF signal to generate a processed baseband signal. RX processing circuitry 305 may transmit the processed baseband signal to speaker 306 (e.g., for voice data) or to processor 307 (e.g., for web browsing data) for further processing.

TX processing circuitry 303 may receive analog or digital voice data from microphone 304 and other outgoing baseband data from processor 307 (e.g. web data, e-mail or interactive video game data). ) can be received. TX processing circuitry 303 may encode, multiplex, and/or digitize outgoing baseband data to generate a processed baseband or IF signal. The RF transceiver 302 may receive the outgoing processed baseband or IF signal from the TX processing circuit 303 and upconvert the baseband or IF signal to an RF signal to be transmitted via one or more antennas 301. can TX processing circuitry 303 may be configured to transmit one or more beams from one or more antennas 301 .

The processor 307 may include one or more processors or other processing devices and may execute the OS 312 stored in the memory 311 to control the overall operation of the UE 116 . For example, processor 307 may control the reception of forward channel signals and the transmission of reverse channel signals by RF transceiver 302, TX processing circuitry 303 and RX processing circuitry 305, according to known principles. can In some embodiments, processor 307 may include at least one microprocessor or microcontroller.

Processor 307 may also execute other processes and programs stored in memory 311, such as processes for beam management. Processor 307 may move data to or from memory 311 as required by an executing process. In some embodiments, processor 307 may be configured to execute applications 313 based on OS 312 in response to signals received from gNBs or an operator. The processor 307 may be coupled to an I/O interface 308 that provides the UE 116 with the ability to connect to other devices, such as laptop computers and portable computers, as non-limiting examples. I/O interface 308 may be a communication path between these accessories and processor 307 .

Processor 307 may also be coupled to touchscreen 309 and display 310 . An operator of UE 116 may use touchscreen 309 to enter data into UE 116 . Display 310 may be a liquid crystal display (LCD), light emitting diode (LED) display, or other display capable of rendering text and/or at least limited graphics, such as from web sites.

Memory 311 may be coupled to processor 307 . Part of memory 311 may include RAM, and another part of memory 311 may include flash memory or other ROM.

Although FIG. 3 shows one example of UE 116 , various changes may be made to FIG. 3 . For example, various components of FIG. 3 could be combined, further divided, or omitted, and additional components could be added as needed. As one example, processor 307 may be divided into multiple processors, such as one or more central processing units (CPUs) and one or more graphics processing units (GPUs). 3 also shows UE 116 configured as a cell phone or smartphone, the UE may be configured to operate with any kind of portable or stationary devices. It should be appreciated that the exemplary UE 116 shown in FIG. 3 is configured to provide any and all of the functionality of the UE described herein.

In order to meet the demand for increased wireless data traffic since the deployment of 4G communication systems, efforts have been made to deploy an improved 5G/NR or pre-5G/NR communication system. Accordingly, the 5G/NR or pre-5G/NR communication system may be referred to as "beyond 4G network" or "post LTE system". 5G/NR communication systems are implemented in high frequency (mmWave) bands, typically above 6 GHz, such as 28 GHz or 60 GHz, achieve high data rates in low frequency bands, such as less than 6 GHz, or support robust coverage and mobility It can be considered to enable. Beamforming, massive MIMO (multiple-input multiple-output), FD (full dimensional)-MIMO, array antenna, analog beamforming, Large-scale antenna technologies may be used in 5G/NR. In addition, in the 5G / NR communication system, distribution for system network improvement is advanced small cells, cloud radio access networks (RANs), ultra-dense networks, device-to-device (D2D) communication , wireless backhaul, mobile networks, cooperative communications, coordinated multi-points (CoMP), reception-end interference cancellation, etc. are in progress.

A communication system may include downlink (DL), which refers to transmissions from a base station or one or more transmission points towards a UE, and uplink (UL), which refers to transmissions from UEs towards a base station or one or more reception points. .

A unit for DL signaling or UL signaling in a cell may be referred to as a slot and may include one or more symbols. A symbol can also function as an additional time unit. A frequency (or bandwidth (BW)) unit may be referred to as a resource block (RB). One RB may include a plurality of sub-carriers (SCs). For example, one slot may have a length of 0.5 ms or 1 ms and may include 14 symbols. An RB may include 12 subcarriers with an inter-SC spacing of 30 kHz or 15 kHz, respectively. A unit of one RB in frequency and one symbol in time may be referred to as a physical resource block (PRB).

DL signals may include data signals carrying information content, control signals carrying downlink control information (DCI), and a reference signal (RS), which may also be referred to as pilot signals. The gNB may transmit data information or DCI through respective physical downlink shared channels (PDSCHs) or physical downlink control channels (PDCCHs). The PDSCH or PDCCH may be transmitted with a variable number of slot symbols including one slot symbol. Briefly, a DCI format for scheduling PDSCH reception by a UE may be referred to as a DL DCI format, and a DCI format for scheduling transmission of a physical uplink shared channel (PUSCH) from the UE may be referred to as a UL DCI format.

A gNB may transmit one or more of several types of reference signals (RS), including a channel state information reference signal (CSI-RS) and a demodulation reference signal (DM-RS). CSI-RS may be mainly used for UEs to perform measurements and provide channel state information (CSI) to the gNB. For channel measurement, non-zero power (NZP) CSI-RS resources may be used. For interference measurement reports (IMRs), channel state information interference measurement (CSI-IM) resources may be used. The CSI process may include NZP CSI-RS and CSI-IM resources.

The UE may determine CSI-RS transmission parameters from the gNB through higher layer signaling such as DL control signaling or radio resource control (RRC) signaling. Transmission instances of CSI-RS may be indicated by DL control signaling or configured by higher layer signaling. The DM-RS can be transmitted normally only within the bandwidth of each PDCCH or PDSCH, and the UE can use the DM-RS to demodulate data or control information.

4A shows a DL slot structure 400 according to an exemplary embodiment of the present disclosure. The DL slot structure 400 shown in FIG. 4A is exemplary only, and FIG. 4A does not limit the scope of the spirit of the present disclosure to any particular implementation. It is noted that in the DL slot structure 400 to be described later, the DCI information may not be located as shown in FIG. 4A and may be located in any appropriate position.

개의 심볼들(402)을 포함할 수 있다. DL 시스템 대역폭은

개의 RB들을 포함할 수 있다. 각 RB는

개의 SC들을 포함할 수 있다. UE는 PDSCH 전송 대역폭의 경우 총

개의 SC들에 대하여

개의 RB들에 배정될 수 있다. DCI를 운반하는 PDCCH는, DL 시스템 대역폭에 걸쳐서 실질적으로 퍼져있는 CCE(control channel element)들로 송신될 수 있다. 제1 슬롯 심볼(404)은 PDCCH를 송신하기 위해 gNB에 의해 사용될 수 있다. 제2 슬롯 심볼(405)은 PDCCH 또는 PDSCH를 송신하기 위해 gNB에 의해 사용될 수 있다. 남은 슬롯 심볼들(406)은 PDSCH 및 CSI-RS를 송신하기 위해 gNB에 의해 사용될 수 있다. 일부 슬롯들에서, gNB는 SS/PBCH(synchronization signals and primary broadcast channel) 블록들과 같이 동기화 신호들 및 시스템 정보를 운반하는 채널들을 송신할 수도 있다.As shown in Figure 4a, DL slot 401 is a gNB can transmit data information, DCI or DM-RS, for example.

number of symbols 402. DL system bandwidth is

RBs may be included. Each RB is

SCs may be included. In the case of the PDSCH transmission bandwidth, the UE

About Dog SCs

may be assigned to RBs. A PDCCH carrying DCI may be transmitted in control channel elements (CCEs) that are substantially spread across the DL system bandwidth. The first slot symbol 404 may be used by the gNB to transmit PDCCH. The second slot symbol 405 may be used by the gNB to transmit PDCCH or PDSCH. The remaining slot symbols 406 may be used by the gNB to transmit PDSCH and CSI-RS. In some slots, the gNB may transmit synchronization signals and channels carrying system information, such as synchronization signals and primary broadcast channel (SS/PBCH) blocks.

UL signals include data signals carrying information content, control signals carrying uplink control information (UCI), DM-RS associated with data or UCI demodulation, and SRS (sounding reference signal) and a random access (RA) preamble enabling the UE to perform random access. The UE may transmit data information or UCI through a physical uplink shared channel (PUSCH) or a physical uplink control channel (PUCCH), respectively. PUSCH or PUCCH may be transmitted through a variable number of symbols including one symbol in a slot. When the UE simultaneously transmits data information and UCI, the UE can multiplex both on PUSCH.

UCI is hybrid automatic repeat request (HARQ)-acknowledge (ACK) information indicating correct or incorrect detection of data transport blocks (TBs) or code block groups (CBGs) in a PDSCH. It may include a scheduling request (SR) indicating whether it has data and CSI reports that enable the gNB to select appropriate parameters for PDSCH or PDCCH transmissions to the UE.

The CSI report from the UE is a channel quality indicator (CQI) that informs the gNB of the maximum modulation and coding scheme (MCS) that allows the UE to detect TB with a predetermined BLER, such as 10% block error rate (BLER), MIMO transmission According to the principle, a precoding matrix indicator (PMI) that tells the gNB how to combine signals from multiple transmit antennas, a CSI-RS resource indicator (CRI) that indicates a CSI-RS resource associated with a CSI report, and a PDSCH for A rank indicator (RI) indicating a transmission rank may be included.

UL RS may include DM-RS and SRS. A DM-RS can normally only be transmitted within the bandwidth of a PUSCH or PUCCH transmission, respectively. gNB may use DM-RS to demodulate information on PUSCH or PUCCH, respectively. SRS may be transmitted by the UE to provide UL CSI to the gNB, and in the case of a TDD system, SRS transmission may provide PMI for DL transmission. In addition, to establish synchronization or initial higher layer connection with the gNB, the UE may transmit a physical random access channel (PRACH).

4B shows a UL slot structure 410 for PUSCH transmission or PUCCH transmission according to an exemplary embodiment of the present disclosure. The UL slot structure 410 of FIG. 4B is exemplary only, and FIG. 4B does not limit the scope of the present disclosure to any particular implementation. It is noted that in the UE slot structure 410 described below, the UCI information may not be located as shown in FIG. 4B, and may be in any suitable position.

개의 심볼들(412)을 포함할 수 있다, UE 시스템 대역폭은 N개의 RB들을 포함할 수 있다. 각 RB는

개의 SC들을 포함할 수 있다. UE는 PUSCH 전송 대역폭(X=S) 또는 PUCCH 전송 대역폭(X=C)의 경우 총

개의 SC들에 대하여

개의 RB들에 배정될 수 있다. 슬롯의 하나 이상의 심볼은, 예컨대 SRS 전송들(414)이나 하나 이상의 UE들로부터의 짧은 PUCCH 전송들을 다중화하는데 사용될 수 있다.As shown in FIG. 4B, a slot 411 is used by the UE to transmit data information, UCI or DM-RS, for example.

symbols 412, the UE system bandwidth may include N RBs. Each RB is

SCs may be included. For the PUSCH transmission bandwidth (X=S) or PUCCH transmission bandwidth (X=C), the UE

About Dog SCs

may be assigned to RBs. One or more symbols of a slot may be used to multiplex SRS transmissions 414 or short PUCCH transmissions from one or more UEs, for example.

5A shows a transmitter architecture 501 using OFDM according to an exemplary embodiment of the present disclosure. The transmitter structure 501 shown in FIG. 5A is only an example, and an actual implementation may have the same or similar structure. 5A does not limit the scope of the present disclosure to any particular implementation.

As shown in FIG. 5A , information bits such as DCI bits or data information bits 502 may be encoded by an encoder module 503 and assigned a time by a rate matcher module 504. /Can be rate matched to frequency resources and can be modulated by the modulator module 505. Subsequently, the modulated and encoded symbols and the DM-RS or CSI-RS module 506 may be mapped to SCs by the SC mapping module 507 controlled by the transmission bandwidth module 508 . An inverse fast Fourier transform (IFFT) may be performed by the filter module 509 . A cyclic prefix (CP) may be added to the output of filter module 509 . The resulting signal may be filtered by a common interface unit (CIU) filter module 510 and transmitted by the RF module 511 as a transmitted signal 512 .

5B shows a receiver architecture 531 using OFDM in accordance with an exemplary embodiment of the present disclosure. The receiver structure 531 shown in FIG. 5B is just an example, and an actual implementation may have the same or similar structure. 5B does not limit the scope of the present disclosure to any particular implementation. As shown in FIG. 5B , received signal 532 may be filtered by filter module 533 . CP removal module 534 can remove cyclic prefix (CP). The filter module 535 may apply fast Fourier transform (FFT). The SC de-mapping module 536 may demap the SCs selected by the bandwidth selector module 537. Received symbols may be demodulated by a channel estimator and demodulation module 538. Rate-matcher module 539 can recover the rate match, and decoder module 540 can decode the resulting bits to provide data information bits 541 . DL transmissions and UL transmissions may be based on an orthogonal frequency division multiplexing (OFDM) waveform including a variant that uses DFT preceding, known as DFT-spread-OFDM.

As described above, in 3GPP Rel-17 study item description (SID) on RedCap NR devices, the purpose may be to support the same set of frequency range 2 (FR2) cases as that of FR1. Beam refinement may be a key feature for FR2 operation in NR. An important issue is related to enabling the beam refinement process for RedCap UEs in RRC_INACTIVE state (which may be referred to herein as RRC inactive state or inactive mode). Accordingly, exemplary embodiments of the present disclosure provide a set of beam refinement procedures that enable RedCap in inactive mode transmission in FR2.

An HST-SFN transmission may be a coherent joint transmission employing only one PDCCH to allocate a set of PDSCH resources. The same PDSCH can be transmitted simultaneously from multiple TRPs. 6 shows an example of an HST-SFN environment 600 where coherent joint transmissions occur. In FIG. 6 , the UE may be moving on a high-speed train, may receive a first PDSCH1 from a first TRP (TRP1), and may receive a second PDSCH1 from a second TRP (TRP2).

From the UE's point of view, the additional DL transmission from TRP2 can be interpreted as an additional DL delay-spread component derived from a single TRP. Due to the fact that each TRP uses independent local oscillators and the UE mobility for each TRP is different, differences in frequency offset may occur in the UE. That is, a UE facing a second TRP (TRP2) away from a first TRP (TRP1) will experience a negative Doppler offset moving away from the first TRP (TRP1) and a positive Doppler offset moving toward the second TRP (TPR2). can In SFN-style transmission, both TRPs can transmit the same TRS and DMRS, so that the UE can perform estimation for the composite propagation channel. In general, coherent joint transmissions may be considered less practical in terms of ideal transport connections and perfect synchronization, as well as accurate channel state information to ensure that DL transmissions at the UE are summed constructively.

[TPR-Specific TRS Transmission]

In SFN transmission, an important factor to consider is the ability to dynamically switch between TRPs. In an SFN-style transmission, this may involve additional SFN TRS/CSI-RS resources allocated to SFN transmissions to derive quasi-colocation (QCL) characteristics. As used herein, quasi co-location (QCL) is when the characteristics of the channel on which the symbol on one antenna port is carried can be inferred from the channel on which the symbol on the other antenna port is carried. can be referred to as being in 7 shows an example of RS overhead in an exemplary bandwidth for configuration of a QCL reference RS in SFN transmission in case of three TRPs. The horizontal axis of FIG. 7 is time t, and the vertical axis is the frequency band f. A total of 7 TRSs are used in FIG. 7, 3 TRSs are used for TRP　A, TRP　B and TRP　C, and an additional 4 TRSs are used for TRP　A+TRP　B, TRP　B+TRP　C, TRP　A+TRP　C and TRP Used for scenarios involving A+TRP　B+TRP　C.

With multiple QCL Reference RSs for the same DMRS port(s), each QCL Reference RS corresponding to a specific TRP (TRP-specific), additional TRS/CSI-RS resources dedicated to SFN transmission need to be configured in the UE. does not exist. This can reduce RS overhead for configuration of the QCL reference RS.

8 shows separate QCL RSs for three TRPs sufficient for dynamic switching between TRP A, TRP B and TPR C. 8, the horizontal axis is time t, and the vertical axis is the frequency band f. Each TRP has an independent QCL reference RS that is frequency-division modulated (FDM) to RSs of other TRPs. Based on this, the three TRPs shown in FIG. 8 can be used in the dynamic switching cases of TRP A, TRP B and TRP C, as well as TRP　A+TRP　B, TRP　B+TRP　C, TRP　A+TRP　C and TRP　A+TRP　B+TRP　C, because each TRS has an independent QCL assumption. For example, if TRP A is used for PDSCH, the PDSCH DMRS can be dynamically indicated to QCL from TRP A to TRS. When TRP A + TRP B is used for PDSCH, the PDSCH DMRS can be dynamically marked to QCL from both TRP A and TRP B to both TRS.

In addition, the corresponding DMRS port(s) in TRS and SFN transmissions may experience multiple channels representing the main path at each TRP. To perform DMRS channel estimation, the UE can first estimate large-scale profiles such as Doppler shift, Doppler spread, average delay and delay spread. With a single QCL reference RS in the case where the TRS and DMRS are QCLed to a single transmission configuration indicator (TCI) state comprising a composite channel of TRPs, the UE is very capable of accurately estimating significantly different Doppler shifts based on the composite TRS. It may be required to have high complexity. Such a complex UE may apply a Wiener filter to the estimated Doppler shifts to improve channel estimation performance. With multiple QCL Reference RSs for the same DMRS port(s), if each QCL Reference RS corresponds to a specific TRP (TRP-specific), the UE needs to estimate and track multiple Doppler shifts from a single combined TRS. does not exist. As a result, UE complexity can be significantly reduced.

9A-9C show three dynamic transition scenarios respectively in an example HST-SFN environment 900 including a first TRP (TPR1), a second TRP (TRP2) and a UE. 9A shows a dynamic transition scenario when PDSCH is transmitted from the first TRP (TPR1). 9B shows a dynamic switching scenario when PDSCH is transmitted from a second TRP (TPR2). 9C shows a dynamic transition scenario when PDSCH is transmitted from both the first TRP (TRP1) and the second TRP (TRP2). Using TRP-specific (i.e., multiple ACL assumptions) TRS transmission, a total of two TRS resources, each with a separate QCL assumption, may be sufficient for dynamic switching for the three scenarios shown in FIGS. 9A-9C. .

With a TRP-specific TRS transmission, a low complexity UE can accurately estimate two different Doppler shifts based on two received TRSs, each with QCL hypotheses. To improve throughput, the UE can still perform per-tap Doppler shift channel estimation. That is, channel coefficients can be calculated using an estimated frequency offset per tap and tap-dependent time domain channel interpolation.

In the following, the functions of TRPs described in various HST-FSN scenarios and methods can be provided by the exemplary base station shown in FIG. 2, and the functions of UEs described in various HST-FSN scenarios and methods are It can be provided by the exemplary UE shown in FIG. 3 .

[Pre-compensation with TRP-specific TRS transmission]

The first embodiment provides cooperation of the network and the UE for precompensation of frequency offsets that can be used to reduce UE complexity. That is, the network can precompensate for different frequency offsets so that the UE is used to estimate different Doppler shifts. To this end, the UE can explicitly report the estimated Doppler shifts using the CSI framework. Alternatively, the UE may implicitly (implicit UE indication) have each TRP estimate Doppler shifts based on the UL signal transmitted by the UE.

Doppler-shift precompensation may be provided by the network using the reference TRP to precompensate for different Doppler shifts for both explicit reporting and implicit UE indication. The reference TRP may be pre-configured or semi-statically indicated to the UE. In one aspect of the first embodiment, a specific (predetermined) TRP transmits a PDSCH in dynamic switching between TRPs, as shown in FIGS. 10A-10C for the three dynamic switching scenarios of FIGS. 9A-9C. It may be TRP. Alternatively, in the second aspect of the first embodiment, a non-predetermined TRP may be used for pre-compensation for different Doppler shifts. The non-predetermined TRP transmitting the PDSCH may be the reference TRP for the UE, as shown in FIGS. 11A-11C for the three dynamic switch scenarios of FIGS. 9A-9C.

In a first aspect of the first embodiment shown in FIGS. 10A to 10C , a predetermined TRP (eg TRP1) known to the UE (eg indicated by a specific TCI state) is always a frequency frequency at the gNB side for all dynamic switching cases. -Can be a reference for offset pre-compensation.

In each of FIGS. 10A to 10C , TRP1 may be a predetermined TRP. In FIG. 10A , TRP1 may transmit TRS to the UE. In FIG. 10B, TRP2 may transmit TRS to the UE. In FIG. 10C both TRP1 and TRP2 may transmit TRS to the UE.

및 TRP2에 관한 도플러 시프트

를 경험할 수 있다. 레퍼런스된 TRP로부터 수신된 TRS에 기초하여, UE는

를 결정할 수 있고, TRP1 및 TRP2 모두에

를 운반하는 UL RS(

)를 송신할 수 있다. 이에 응답하여, TRP1은

를 결정할 수 있고,

상으로 DL을 송신할 수 있다. TRP2는

및

를 결정할 수 있고,

를 운반하는 DL을 송신할 수 있다. TRP1으로부터 수신된 DL에 응답하여, UE를 위한 반송파 주파수는

가 될 수 있다.UE shifts Doppler with respect to TRP1

and Doppler shift for TRP2

can experience Based on the TRS received from the referenced TRP, the UE

can be determined, and for both TRP1 and TRP2

UL RS (

) can be sent. In response, TRP1

can determine,

DL can be transmitted over TRP2 is

and

can determine,

It is possible to transmit DL carrying . In response to the DL received from TRP1, the carrier frequency for the UE is

can be

In the second aspect of the first embodiment shown in FIGS. 11A to 11C , the TRP transmitting the PDSCH in each of the three dynamic switching cases may be a reference TRP for frequency-offset compensation provided to the network side. In cases (1) of FIG. 11C and (2) of FIG. 11C in which both TRP1 and TRP2 transmit PDSCH, one of the TRPs may be regarded as a reference TRP. (1) of FIG. 11C shows the case where TRP1 is the reference TRP, and (2) of FIG. 11C shows the case where TRP2 is the reference TRP.

는 도 11a 내지 도 11c에 도시된 경우들에서 동적 전환을 핸들링할 때 동적으로 변동할 수 있다. TRP-특정 TRS 전송으로, 다중 QCL 가정이 동일한 DMRS 포트들에 대해 고려될 수 있고, UE는 최대 2개의 TCI 상태들을 가지는 TCI 코드포인트로 활성화될 수 있다. 이에 따라, TRP당 하나의 TCI 상태의 배정으로, UE는 도플러 시프트의 QCL 소스가 DCI에 적절하게 표시되는 한, 어떠한 전송-동적 경우가 사용될지 결정할 수 있고, 채널 추정을 위한 케이스-특정 도플러 시프트를 처리할 수 있다. 그러나, 도 10a 내지 도 10c에 도시된 주파수-오프셋 사전보상에서, 수신된 신호의 반송파 주파수

는 도 9a 내지 도 9c의 동적-전환 경우들에서와 동일하게 남아있을 수 있다. 또한, 네트워크는 레퍼런스 TRP를 UE에 미리 구성하거나 반정적으로 표시해야하기 때문에, 도 10a 내지 도 10c에 도시된 주파수-오프셋 보상을 위한 시그널링 오버헤드는 도 11a 내지 도 11c에 도시된 주파수-오프셋 사전보상을 위한 시그널링 오버헤드보다 작을 수 있다. 더욱 작은 시그널링 오버헤드에 기초하여, 미리 결정된 TRP가 gNB 측에서 주파수-오프셋 보상을 위한 레퍼런스 TRP로 간주될 수 있는 도 10a 내지 도 10c에 도시된 실시예가 도 11a 내지 도 11c의 접근법들보다 유리할 수 있다.Carrier frequency of the received signal

may vary dynamically when handling dynamic transitions in the cases shown in FIGS. 11A-11C. With TRP-specific TRS transmission, multiple QCL assumptions can be considered for the same DMRS ports, and a UE can be activated with a TCI codepoint with up to two TCI states. Thus, with the assignment of one TCI state per TRP, the UE can decide which transmit-dynamic case to use, as long as the QCL source of the Doppler shift is appropriately indicated in the DCI, and the case-specific Doppler shift for channel estimation. can handle However, in the frequency-offset precompensation shown in FIGS. 10A to 10C, the carrier frequency of the received signal

may remain the same as in the dynamic-switching cases of FIGS. 9A-9C. In addition, since the network must preconfigure or semi-statically indicate the reference TRP to the UE, the signaling overhead for frequency-offset compensation shown in FIGS. 10A to 10C is the frequency-offset dictionary shown in FIGS. 11A to 11C. It may be smaller than the signaling overhead for compensation. Based on smaller signaling overhead, the embodiment shown in FIGS. 10A-10C in which a predetermined TRP can be regarded as a reference TRP for frequency-offset compensation at the gNB side may be advantageous over the approaches of FIGS. 11A-11C. there is.

는 3개의 동적 전환 경우들 각각에 대한 동적 스위치에서 동일하게 유지될 수 있다.In a third aspect of the first embodiment, the network may provide precompensation for different frequency offsets per TRP without assigning a reference TRP. Each TRP may be responsible for recompensation of the frequency offset corresponding to the path between the TRP and the UE. Figures 12a to 12c show frequency-offset-compensation schemes respectively for the three dynamic switching cases where each TRP is responsible for its corresponding frequency-offset precompensation. Similar to the examples of FIGS. 10A to 10C , the carrier frequency of the received signal

may remain the same in the dynamic switch for each of the three dynamic switching cases.

In the case of an NZP-CSI-RS-ResourceSet configured with the higher layer parameter tris-Info , the UE shall assume that the antenna port is the same as the same port index of the NZP CSI-RS resources configured in the NZP-CSI-RS-ResourceSet . Accordingly, all of the different TRS resources in the set can be represented as one resource.

The technical idea of the present disclosure provides that TRP-specific TRS reference signals are transmitted from two TRPs configured as one set, and since the QCL information of NZP CSI-RS is configured at the resource level, FIGS. 10A to 10C, FIGS. 11a to 11c and 12a to 12c are applicable to all the scenarios described, and the overhead of TRS set configuration can be reduced. It is noted that the antenna ports with the same port index of the TRS resources configured in the set can be the same only if the resources have the same TCI state.

Each NZP-CIS-Resource may be composed of a frequency domain allocation bit string in resource mapping in 3GPP Specification 38.311 as shown below. Of all possible mappings, only row 1 can be used for the TRS reference signal, since row 1 has a high density of 3 REs per RB providing measurement accuracy for tracking time and frequency offsets. A 4-bit string in row 1 with only one bit set to “1” can be used to indicate the first RE in a frequency-domain assignment.

CSI-RS-ResourceMapping Information Element

A TRS resource set is such that the CSI-RS- ResourceMapping of TRS reference signals transmitted from two TRPs (i.e., NZP CSI-RS resources) use different bit strings to have non-overlapping frequency-domain RE assignments. can be configured. TRS transmission from two TRPs can be simultaneous (ie, with the same firstOFDMSymbolInTimeDomain configuration) or with the same symbol offset (ie, with different firstOFDMSymbolInTimeDomain configurations). In the case of aperiodic TRS reference signals, transmissions from two TRP nodes can be in the same slot because the aperiodicTriggeringOffset parameter is not individually configured for each resource but configured for each set. The aperiodicTriggeringOffset parameter may indicate a time offset between a slot receiving an aperiodic trigger and a slot during which the resource set is transmitted.

Performance in the HST scenario can be particularly sensitive to Doppler measurement errors based on high mobilities and corresponding high Doppler shifts. In order to have an accurate estimate of the Doppler shift in the vicinity of the TRPs, the frequent rate of transmission of the TRS can be used. However, even the low speed of the TRS may be sufficient in areas relatively far from the TRPs. Accordingly, the MAC CE may dynamically update the TRS transmission period for the HST distribution scenario in order to avoid RRC reconfiguration overhead.

Similarly, if the network precompensates for the frequency offset, the accuracy of the Doppler shift estimation at the gNB may be affected by the UL RS transmission rate. While frequent rates of sounding reference signal (SRS) transmission can be used in the vicinity of TRSs, even low rates of SRS transmission can be sufficient in areas far from TRPs. MAC CE may dynamically update the UL RS transmission period for HST deployment scenarios.

[Network frequency offset precompensation with explicit UE reporting]

One embodiment of network frequency-offset precompensation may provide explicit UE reporting. For this embodiment, the UE may explicitly report the different Doppler shifts measured for each TRP as part of the CSI reporting to the gNB. With TRP-style TRS/CSI RS transmission, large-scale profile measurements including Doppler shift and Doppler spread can be performed independently for each TRP. However, additional reporting of such a Doppler shift may increase reporting overhead and may include UE estimation error and/or feedback latency.

The current specification framework for CSI report triggering and transmission can be used for explicit UE reporting. One method may have the network utilize the channel measurement parameters to calculate the Doppler shift. Another way is to introduce a new report quantity for Doppler shift in CSI-ReportConfig . TRS may be a CSI reference-signal resource configured in a specific configuration to maximize tracking performance. The trs -info flag in the NZP-CSI-RS- ResourceSet parameter structure may indicate that the CSI RS resource set is used as a TRS. An example of a specification change to handle explicit UE reporting (trs-dopplershift) of Doppler shift(s) per TRP is shown below.

CSI-ReportConfig information element

Since the current specification explicitly prohibits TRS from being included in CSI reporting, the introduction of a new report quantity for Doppler shift in CSI-ReportConfig may involve removing that restriction. That is, the UE can be configured with CSI-ReportConfig linked to CSI- ResourceConfig including NZP-CSI-RS-ResourceSet configured with trs-Info . In addition, the UE may be configured with CSI-ReportConfig having a higher layer parameter reportQuantity set to something different from ' none ' for the NZP CSI-RS resource set configured with trs-Info .

[Network Frequency Offset Precompensation with Implicit UE Indication]

Another embodiment of network frequency-offset precompensation provides implicit UE indication. TRS transmission in this method may be TRP-specific (ie, TRS _TRP as shown in FIGS. 13 to 15 ).

를 사전보상할 수 있다.13 shows a fourth aspect of a first embodiment of network frequency-offset precompensation using a three-step method with implicit UE indication according to the spirit of the present disclosure. The method may begin at step 1301 with a TRS transmission. A set of TRP-specific TRSs may be transmitted from two TRPs (TRP1, TRP2) (ie, with independent QCL assumptions). The UE can estimate the carrier frequency and two Doppler shifts based on the received TRS set. In step 1302, the UE may transmit a modulated UL reference signal (eg, SRS) with a carrier frequency estimated based on the received TRS set to two TRPs (TRP1, TRP2). In step 1303, the network can estimate the frequency offset difference of the UL RS (eg SRS) received in the two TRPs, and for the DL transmission (eg TRS, DMRS, PDSCH) from the non-reference TRP frequency offset difference

can be compensated in advance.

In step 1301 of FIG. 13, an initial set of TRS transmissions may be transmitted for the purpose of frequency offset estimation at the UE. Also, this may be the purpose of the QCL RS for UL RS (eg, SRS) transmission in step 1302. TRS transmission may occur only as aperiodic transmission in this aspect of the first embodiment, and may not be used for all DMRS and PDSCH transmissions. Also, in the current specification, the UE may not be obligated to use TRS for carrier-frequency estimation, and may use any other DL RS to maintain a frequency loop. That is, the main process for precompensation of different Doppler shifts by the network for DL transmission may include periodic transmission of UL RS (in step 1302) and TRS (in step S1303) in FIG. 13 .

14 illustrates a fifth aspect of a first embodiment of network frequency-offset precompensation using a two-step method starting with UL RS transmission according to an exemplary embodiment of the present disclosure. The two-step method may be similar to steps 1302 and 1303 of FIG. 13 .

) 사전보상은, 모든 TRS, DMRS 및 PDSCH에 대한 도 13에 도시된 제1 실시예의 제4 측면 및 TRS 전송을 제외한 DMRS 및 PDSCH에 대한 도 14에 도시된 제1 실시예의 제5 측면 중 하나에 사용될 수 있다.Frequency-offset difference in gNB for DL transmission (i.e.,

) Precompensation is in one of the fourth aspects of the first embodiment shown in FIG. 13 for all TRSs, DMRSs and PDSCHs and the fifth aspect of the first embodiment shown in FIG. 14 for DMRSs and PDSCHs excluding TRS transmissions. can be used

In the fourth and fifth aspects of the first embodiment, TRS overhead for dynamic-switching transmission can be reduced. However, the existing QCL rule for Delay-Related Large Profile may not hold because TRSs may be transmitted TRP-specific while DMRS and PDSCH are transmitted in an SFN manner. To address this, a Rel-17 UE can be activated using a TCI codepoint with two TCI states. In the current specification, the two active TCI states can correspond to different DMRS ports. Here, the UE can be associated with all of the TCIs to the PDSCH DMRS port(s) simultaneously (ie, one TCI state per each TRP). That is, multiple-QCL assumptions can be considered for the same DMRS port(s). The DMRS antenna port(s) associated with each TRP may be configured to be QCLed from the TRP to the transmitted TRS.

For Doppler-shift-related large-scale profiles, if the frequency offset is precompensated for the DMRS and PDSCH as well as the TRS (i.e. the fourth aspect), then any issues with the UE-side frequency offset tracking or QCL rule based on the received TRS may not even occur. Since the QCL RSs for DMRS and PDSCH are TRSs in the second TRS transmission, QCL rule violation for Doppler shift information may not occur. In addition, in the case of the second TRS transmission pre-compensated for the frequency offset, no issue may occur when the UE estimates and compensates for the frequency offsets of the DMRS and PDSCH according to the received TRS.

If the frequency offset is precompensated for DMRS and PDSCH except for TRS (i.e., the fifth aspect), the QCL rule for Doppler shift may be violated for DMRS and DMSCH transmissions from non-reference TRPs. The UE may estimate and precompensate for the frequency offset based on the received TRS. If the DMRS and PDSCH except TRS are pre-compensated for the frequency offset, the UE can estimate the frequency offset based on the TRS and apply the estimate to the received DMRS and PDSCH already compensated by the network. To address the QCL rule violation issue in the first embodiment, a new QCL type can be used for TRSs transmitted from non-reference TRPs containing only delay-related large profiles (ie delay spread and average delay). That is, the QCL RS for the PDSCH DMRS can be a TRS transmitted from the reference TRP with QCL type B, and the second TRS transmission from the non-reference TRP transmits delay-spread and average-delay information for the path from the non-reference TRP to the UE. It can only be used for extraction. In addition, in order to solve the issue of frequency-offset tracking based on TRS at the UE side, if the TRS transmission is TRP-specific, the gNB may indicate to the UE to track the frequency offset based only on the TRS received from the reference TRP (i.e. , pre-configured to a specific TCI state and displayed semi-statically). In the fourth and fifth aspects of the first embodiment shown in Figs. 13 and 14, respectively, the network may pre-compensate for differences in frequency Doppler shifts based on one TRP as a reference TRP. As mentioned above, the network can precompensate for Doppler shifts individually for each TRP. The methods and descriptions of FIGS. 13 and 14 can be extended and applied to situations where the Doppler frequency shift is independently precompensated for each TRP by the network.

15A and 15B show examples of a three-step method and a two-step method, respectively, for network frequency-offset precompensation that provide TRP-specific frequency offset precompensation independently for each TRP, according to an exemplary embodiment of the present disclosure. . The three-step method of FIG. 15a may be considered for a situation in which frequency offsets are pre-compensated for all DL transmissions (ie, TRS, DMRS, and PDSCH). In a two-step method, the uncompensated TRS may not be considered as the QCL RS of the PDSCH DMRS due to QCL rule violation, while the channel estimation is still performed with the QCL RS of the PDSCH DMRS to extract the Doppler-shift-related large-scale profile. can be related

[SFN-method TRS transmission]

SFN-style TRS transmission may involve a high complexity UE to accurately estimate significantly different Doppler shifts based on the composited TRS. If the network precompensates for different Doppler shifts from the two TRPs, a high complexity UE for channel estimation and PDSCH demodulation may not be needed.

In embodiments using a 3-step or 2-step method for network frequency offset precompensation with TRP-specific TRS transmission, the estimated carrier frequency at the UE is used only for UL RS transmission with two TRPs. The value may not need to be exact, and the network may precompensate for the Doppler shift difference of the two TRPs.

A second embodiment may relate to UE and network cooperation with SFN-style TRS transmission (ie, TRS _SFN ). Using SFN-style TRS transmission with network frequency-offset precompensation can reduce UE complexity with backward compatibility with existing HST-SFN deployment scenarios, but high TRS overhead may still be involved.

[Network Frequency Offset Precompensation with Implicit UE Indication]

16A and 16B illustrate a second embodiment of a three-step method and a two-step method for network frequency-offset precompensation using SFN-style TRS transmission with implicit UE indication according to exemplary embodiments of the present disclosure. represent each. In the embodiment shown in FIG. 16A, a set of TRSs may be transmitted from two TRPs in step 1602. At step 1602, the UE may transmit a UL reference signal to the two TRPs. In step 1603, the network can estimate the frequency offset difference in the two TRPs and precompensate for the Doppler shift difference for DL transmission for the non-reference TRP. In this embodiment, TRS transmission in both step 1601 and step 1603 may be based on SFN-scheme. The embodiment shown in FIG. 16B is similar to the embodiment of FIG. 16A, but as step 1601, the first step is not used in a two-step method, so it can start at step 1602. Since the channel estimation is related to the QCL source of the PDSCH DMRS for Doppler shift, the embodiment of FIG. 16A can be precompensated for the DMRS and PDSCH as well as the TRS, and no additional resources are provided for QCL rule violations, although not substantial. Unless otherwise, the SFN-mode TRS may not be the QCL RS in the embodiment of FIG. 16B due to QCL rule violation.

For the SFN-mode TRS transmission in FIG. 16A, the UE can estimate the UL carrier frequency for the SRS transmission based on the received composite TRS. A high complexity UE may track multiple Doppler shifts from a single combined TRS, and the UE may most likely estimate a wrong frequency offset in step 1602 . However, since the estimated carrier frequency is only used for UL RS transmission with two TRPs for the network to estimate and compensate for the frequency offset difference of the two TRPs, the value of the estimated carrier frequency at the UE will be independent of any significant operational error. can

For the delay-related large-scale profile using the embodiments of FIGS. 16A and 16B, there is no QCL rule violation considering the DRMS and QCL RS, and the PDSCH requires both the TRS and the corresponding DMRS port(s) to be configured for each TRP. It may be a TRS in the second TRS transmission experiencing a composite channel considering the main path. However, SFN-style transmission may involve high TRS overhead to derive the QCL characteristics of dynamic switching between TRPs.

The frequency offset can always be compensated for not only the TRS but also the DMRS and PDSCH for Doppler-shift related large-scale profiles in the embodiments of FIGS. No issues with offset tracking and compensation may arise.

17A and 17B show a three-step method and a two-step method respectively using SFN-style TRS transmission with independently provided network precompensation for each TRP according to exemplary embodiments of the present disclosure. Descriptions provided for FIGS. 16A and 16B are applicable to the examples of FIGS. 17A and 17B .

Another aspect of the second embodiment may combine SFN and TRP-specific TRS transmission for a three-phase method as shown in FIG. 18 . At step 1801, a TRS transmission may be formed in an SFN manner. At step 1802, the UE may transmit UL RS. At step 1803, a second TRS transmission may be sent TRP-specific. TRP-specific transmission can provide independent delay-spread information estimation and TRS overhead reduction for dynamic switching. Also, similar to TRP-specific TRS transmission, frequency-offset difference precompensation at gNB for DL transmission may be used for all TRS, DMRS, and PDSCH, or may be used for DMRS and PDSCH except for TRS transmission. there is.

The second set of TRSs can be considered as QCL RSs for DMRS and PDSCH. With TRP-specific RSs, the existing QCL rules for delay-related large profile may not be maintained, which may be because TRSs are transmitted TRP-specific while DMRS and PDSCH are transmitted in SFN fashion. To address this issue, a Rel-17 UE can be activated with a TCI codepoint with two TCIs. In the current specification, the two active TCI states can correspond to different DMRS ports. Here, the method is that the UE can be associated to the PDSCH DMRS port(s) with both TCIs simultaneously (ie one TCI state per each TRP). That is, multiple QCL assumptions can be considered for the same DMRS ports. A DMRS antenna port associated with each TRP may be configured to be QCLed from the TRP to the transmitted TRS.

In the dynamic-switching scenario of FIG. 9a for a large-scale Doppler-shift related profile using the method of FIG. 18, no issue arises for UE-side frequency offset tracking and compensation based on the received TRS and QCL rule in the Doppler-shift information. may or may not However, the QCL RS of the PDSCH DMRS may be the second TRS transmitted from the reference TRP with QCL type B, and a new QCL type may be introduced for the TRS of the non-reference TRP containing only the delay-related large profile. In addition, the gNB must indicate to the UE that only the TRS of the reference TRP is considered as the QCL for the Doppler shift-related large profile.

19 illustrates another aspect of a second embodiment combining SFN and TRP-specific TRS transmissions with network precompensation of independently provided Doppler shift for each TRP according to an exemplary embodiment of the present disclosure. As for the description of the aspect of the second embodiment shown in FIG. 18, the example shown in FIG. 19 is that the frequency offset is precompensated for all DL transmissions (i.e., TRM, DMRS and PDSCH) based on the QCL rule-violation issue. It is applicable to aspects of the second embodiment shown in FIG. 19, except that only the situation described is considered.

Table 1 presents a summary of some features and characteristics associated with the first and second embodiments.

TRP-specific
(TRP-specific) SFN-method
(SFN-manner) Combined SFN-TRP specific
(Combined SFN-TRP specific) Violation of QCL rule for delay, spread average delay information TRS overhead, UE complexity Violation of QCL rule for delay, spread average delay information Reduced TRS overhead, low UE complexity Absence of QCL rule violations;
backward compatibility backward compatibility, reduced TRS overhead,
low UE complexity

[Assuming QCL of TRS as target RS]

QCL relationship information can assist the UE with channel estimation, frequency offset estimation and synchronization processes. As shown below, the QCL relationship of the TRS reference signal may be configured for each resource through NZP-CIS-RS-Resource for periodic resources. In the case of semi-persistent resources, the QCL relationship of the TRS reference signal may be established through a medium access control (MAC) control element (CE) triggering process as shown in FIG. 20 . In the case of aperiodic resources, the QCL relationship of the TRS reference signal may be configured through a DCI triggering process for aperiodic resources, as shown below.

a) periodic

NZP-CSI-RS-Resource information element

b) aperiodic

CSI-AperiodicTriggerStateList information element

In the case of a semi-permanent CSI-RS resource set activated/deactivated by MAC CE (FIG. 20), the MAC CE structure shows that the index of NZP-CSI-RS-ResourceSet includes not only semi-permanent NZP CSI-RS resources but also resources in the indicated resource set. A point including TCI-StateIds that can be used as a QCL resource for can be indicated. In the case of aperiodic CSI-RS, the CSI request field in DCI format 0_1 may occupy 6 bits (determined by the higher layer parameter reportTriggerSize in CSI-MeasConfig ) selecting one of all trigger states. TCI status and QCL information can be configured inside CSI- AssociatedReportConfigInfo for each nzp-CSI-RS .

Large-scale radio-channel characteristics such as Doppler shift, Doppler spread, average delay and delay spread can be common across different antenna ports. A QCL-type relationship may be introduced to assist the UE with channel estimation, frequency-offset estimation and synchronization processes in reception of PCCH and PDSCH. In the current specification, four different types of QCL relationships can be defined below to indicate channel scale characteristics across a set of QCL antenna ports.

QCL type A: {Doppler shift, Doppler spread, average delay, delay spread}

QCL type B: {Doppler shift, Doppler spread}

QCL Type C: {Doppler shift, average delay}

QCL Type D: {spatial receiver parameters}

For all embodiments of the present specification, the QCL reference signal for TRS transmission in the first step (applicable to the three-step method) is a specific synchronization signal / physical broadcast channel (SS / PBCH) block, or delay and Doppler-shift It may be any other CSI reference signal with QCL type A that covers the QCL relationship for all relevant large-scale profiles. In the first step, a QCL type D reference signal for TRS transmission may be used as a corresponding TRP specific SS/PBCH block.

However, in the case of the second TRS transmission (in the third step in the three-step method or the second step in the two-step method), the circumstances for configuring the TCI state and QCL information may be different. The QCL reference signal of the second transmitted TRS is different depending on the fact that the network pre-compensates for the frequency offset for all TRS, DMRS and PDSCH, or the fact that the network pre-compensates for the frequency offset for DMRS and PSCH except TRS. can be defined as In both types of cases (three-step or two-step method), the QCL type D reference signal for the second TRS transmission may be the corresponding TRP-specific SS/PBCH block or the first TRS transmitted from the corresponding TRP.

In a three-step method, the QCL RS of the second TRS transmitted from the reference TRP may be the first TRS transmitted from the reference TRP. Alternatively, the QCL RS of the first TRS transmitted from the reference TRP with QCL type A (ie, both Doppler shift, Doppler spread, average delay and delay-spread information) may be the first TRS transmitted from the reference TRP. Also, for the delay-related large profile, the QCL RS for the second TRS transmitted from the non-reference TRP is the first TRS transmitted from the TRP, or the new QCL type definition containing only average delay and delay-spread information, transmitted from the TRP. It may be the QCL RS of the first TRS. For the Doppler-shift-related large profile, the QCL RS for the second TRS transmitted from the non-reference TRP is the QCL RS of the first/second TRS transmitted from the reference TRP, or the first/second TRS transmitted from the reference TRP as QCL type B. can be

Since there may be no TRS transmission in the first step of the two-step process, the QCL RS of the TRS transmitted from the reference TRP may be a specific SS/PBCH block or any other CSI reference signal with QCL type A. The QCL RS of a TRS transmitted from a non-reference TRP may be a specific SS/PBCH block, or any other CSI reference signal with new QCL types for delay spread and average delay information and Doppler shift and Doppler spread information. The QCL RS of the TRS may be a TRS transmitted in the reference TRP or a QCL RS of the TRS transmitted in the reference TRP, which is QCL type B.

In the current specification, each TCI-state may contain a QCL relationship to one or more DL reference signals with two different QCL types. For the second TRS transmission from the non-reference TRP in the three-stage method and for the TRS transmission in the two-stage method, QCL type D as well as two other different QCL types (i.e., a new QCL type for delay-related large profile and Doppler QCL type B) for shift-related massive profiles can be used. To address this issue, the specification can be modified to allow configuration of DL reference signals in each TCI state as well as three different QCL types.

In a three-step method, the QCL RS of the second TRS transmitted from each TRP can be the first TRS transmitted from the TRP, or the first TRS QCL RS transmitted from the TRP with QCL type A. In a two-step method, the QCL RS of the TRS transmitted from each TRP can be a specific SS/PBCH block or any other CSI reference signal with QCL type A.

Also, with three-level network precompensation, there can be two different situations to consider. First, both TRS transmissions are from the same resource set, and second, two different TRS resource sets can be configured for the first and second TRS transmission.

The first situation relates to updating the QCL information for the second TRS transmission, since the network precompensation of the frequency offset breaks the already configured QCL relationship information of the TRS resources. In this situation, MAC CE can be used to update QCL information of TRS resources in a set similar to the current MAC CE structure for activation/deactivation of semi-persistent CSI-RS as shown in FIG. 20 . Alternatively, the network may construct only QCL type D, a new QCL type containing only delay-related large profile information, and corresponding reference signals in the TCI state of the TRS as the source RS. RS of QCL type B for TRS as source RS may be TRS itself.

Also, since the second TRS transmission is not precompensated by the network, the first scenario assumption can be compatible without further impact. In this scenario, the QCL type D reference signal may be the corresponding TRP-specific SS/PBCH block.

In the case of the second scenario assumption, the QCL RS of the second TRS transmitted from the reference TRP may be the first TRS transmitted from the TRP or the QCL RS of the first TRS transmitted from the TRP with QCL type A. The QCL RS for the second TRS transmitted from the non-reference TRS may be the first TRS transmitted from the TRP or the QCL RS of the first TRS transmitted from the TRP with QCL type A. In the case of a large delay-related profile, the QCL RS for the second TRS transmitted in the non-reference TRP may be the first TRS transmitted in the corresponding TRP. Alternatively, the QCL RS of the first TRS transmitted from the corresponding TRP may include a new QCL type including only average delay and delay-spread information. In the case of a Doppler-shift related massive profile, the QCL RS for the second TRS transmitted from the non-reference TRP may be the first/second TRS transmitted from the reference TRP. Alternatively, the QCL RS of the first/second TRS may be transmitted from the reference TRP as QCL type B. In a second scenario, the QCL type D reference signal may be the corresponding TRP-specific SS/PBCH block or the first TRS transmitted from the corresponding TRP.

With a frequency-offset precompensated TRS, the second TRS transmitted from the non-reference TRP must consist of a dynamic carrier frequency, since the Doppler frequency shift changes over time as the UE moves and changes speed. Since different TRS transmission cases may have different precompensation states, the UE's frequency tracking mechanism may suffer from averaging/accumulation problems. This issue can deal with dynamic QCL information update for the second TRS transmission. As described above, dynamic update may be used based on the fact that network precompensation of frequency offset breaks already configured QCL relationships for TRS resources. With the dynamic update of the QCL source RS, TCI state changes for the precompensated TRS can provide an indication that the UE does not average/accumulate over TRS transmission cases.

An alternative solution may be that the carrier frequency estimate may indicate that the gNB only uses the TRS transmitted from the reference TRP to maintain the averaging/accumulation structure of the frequency loop. The reference TRP can be realized either by QCL indication in the DCI scheduling PDSCH or by pre-configured/semi-statically indicated to the UE.

[TRP-specific TRS and DMRS transmission]

With a TRP-specific TRS transmission, the UE can estimate two significantly different large-scale profiles, especially for Doppler-shift, based on the two separate TRSs. However, the UE may still involve high complexity for per-tap Doppler shifts channel estimation. That is, channel coefficients can be calculated using the estimated per-tap frequency offset, and then tap-dependent time-domain channel interpolation can be performed to improve channel-estimation performance and throughput. Another solution to improve DMRS channel estimation performance with low complexity UE is for each TRP to use an independent DMRS port in PDSCH.

With TRP-specific TRS and DMRS transmissions, the UE can orthogonally estimate the propagation channel for each TRP based on each DMRS antenna port mapped to each TRP. The UE can then reconstruct the composite SFN channel by combining the channels estimated from the different TRPs. This can reduce the complexity of the UE channel estimation algorithm with improved performance. Thus, cooperation of the network for pre-compensation of frequency Doppler shifts may no longer be used, and the UE can handle significantly different frequency offsets from the two TRPs with low complexity.

The advanced Rel-17 MAC-CE can activate two TCI states per TCI codepoint. This may enable the UE to associate a DMRS with both TCIs simultaneously. To address this, one solution is a comb-like TCI state assignment in which even-comb REs can be assigned to the first TCI state and odd-comb REs can be assigned to the second TCI state. can be used. In the case of DMRS type 1, this may mean that each TCI state can be assigned to one CDM group. Accordingly, when generalizing the present solution, each CDM group can be assigned to one TCI state for at least DMRS type 1.

Another solution is to assign a TCI state in a TD-OCC scheme where two orthogonal DMRS ports in one CDM group are assigned to two different TCI states. All embodiments herein may allow the UE to use an orthogonal channel estimation algorithm.

[Dynamic conversion of Rel-16 and Rel-17 methods]

For TRP-based precompensation, the same DMRS port(s) can be associated with up to two TCI states. This can be interpreted as an implicit indication/switching between a Rel-17 SFN-based frequency-offset precompensation scheme and a single TRP or Rel-15 SFN frequency-offset precompensation scheme. With reuse of the Rel-17 Advanced TCI States Enable/Disable MAC CE structure, as shown in Figure 21, each codepoint in the TCI field in the DCI for UE-specific PDSCH can be mapped to up to two TCI states. can With this structure, when Ci = 0 (ie, a TCI codepoint in DCI indicates a TCI state ID having only one mapped TCI state), the PDSCH transmission may be a single TRP, and when Ci = 1 (ie, In DCI, a TCI codepoint indicates a TCI state ID having two mapped TCI states), PDSCH transmission may be Rel-17 SFN scheme.

Both Rel-17 SFN schemes and Rel-16 non-SFN schemes (ie SDM, FDM and TDM schemes) may be beneficial for HST deployment scenarios. Rel-17 SFN schemes can provide high reliability/coverage for cell edge or high-speed UEs, while Rel-16 non-SFN schemes can provide high throughput for cell center or low-speed UEs. Accordingly, the network must support dynamic switching/indication of scheduled PDSCH between Rel-16 non-SFN and Rel-17 SFN schemes.

A TRP-specific TRS transmission with a precompensated frequency offset is applied to QCL type D as well as to two separate QCL types: one for the delay-related large profile (i.e., the new QCL type) and the Doppler-shift related large profile. for one (i.e., QCL type B). This may mean that up to three different QCL types can be introduced in one TCI state to handle a TRS transmission with a precompensated frequency offset. This advanced TCI state may be an indication of the Rel-17 SFN scheme. The UE may determine that the PDSCH was transmitted in Rel-17 SFN scheme or Rel-16 non-SFN schemes based on a number of different QCL types defined within the indicated TCI state.

[PTRS Progress and CPE Rewards]

In Rel-17, PDCCH and PDSCH in HST-SFN scenarios can be transmitted in SFN scheme in two TCI states. A PDSCH transmission with two TCI states will involve two phase tracking reference signal (PTRS) ports for accurate phase tracking in the UE, especially when different panels are used to simultaneously receive PDSCHs transmitted from different TRPs. (each TCI state corresponds to one TCI state).

The current specification supports two PTRS ports for the SDM scheme in multi-TRP where two TCI states are indicated by one TCI codepoint. The first PTRS port may be associated with the lowest indexed DMRS port within DMRS ports corresponding to the first indicated TCI state, and the second PTRS port may be associated with the lowest indexed DMRS port within DMRS ports corresponding to the second indicated TCI state. It can be. To extend the current specification for multi-TRP cases in HST-SFN scenarios, two port PTRS can be supported to provide accurate phase tracking in the UE where each PTRS port corresponds to one TCI state.

Two scenarios can be considered for DMRS transmission in HST-SFN scenarios, TRP-specific DMRS transmission (SFN TRP-specific) and SFN mode DMRS transmission (SFN mode). For both these two transmission types, support of 2-port PTRS can result in more accurate phase tracking at the UE.

In the current specification, frequency density, time density, resource-element offset, and energy per resource element (EPRE) ratio of PTRS may be RRC configured through higher layer parameter PTRS-DownlinkConfig. With the 2-port PTRS approach to HST-SFN DL transmission and the current specifications described below, these parameters may be RRC configured for each of the PTRS ports. The number of PTRS ports can be RRC configured similarly to the PTRS configuration for UL transmission in the current specification. With dynamic switching between Rel-17 SFN mode and single TRP or Rel-15 SFN mode, the maximum number of PTRS ports can be semi-statically configured, and the UE can ignore certain PTRS ports when handling unrelated PDSCHs. . Alternatively, the number of PTRS ports can be dynamically updated/activated. This may be possible with an explicit RRC configuration of two PTRS ports for the Rel-17 SFN scheme that can be activated via DCI. The number of PTRS ports may be implicitly indicated by a TCI codepoint in DCI. With the advanced TCI states activation/deactivation MAC CE structure, each codepoint in the TCI field in the DCI for UE-specific PDSCH can be mapped to up to two TCI states. With this structure, when Ci = 0 (i.e., when a TCI codepoint in DCI indicates a TCI state ID with only one mapped TCI state), the PDSCH transmission can be a single TRP with one port PTRS; Ci = 1 (i.e., when a TCI codepoint in DCI indicates a TCI state ID with two mapped TCI states), the PDSCH transmission may be Rel-17 SFN scheme with two PTRS ports. Alternatively, signaling of two PTRS ports may be possible through MAC CE activation.

[Two port PTRS in TRP-specific DMRS transmission]

Channel estimation can be performed orthogonally for each TRP based on the corresponding DMRS antenna port in the case of a TRP-specific DMRS transmission scheme, and accordingly, phase noise is reduced when each PTRS port corresponds to one TRP (ie, TCI state). Assuming corresponding two TRPS ports, it can be orthogonally estimated and compensated for each TRP. The association of two TCI states and DMRS is a comb in which even-comb REs can be assigned to the first TCI state (i.e., first TRP) and odd-comb REs can be assigned to the second TCI state (i.e., second TRP). This can be done through assignment.

Alternatively, TD-OCC scheme assignment can be used whereby two orthogonal DMRS ports in one CDM group can be assigned to two different TCI states. In both of these two scenarios, the first PTRS port can be associated with the lowest indexed DMRS port within the DMRS ports corresponding to the first TRP (i.e., the first indicated TCI state), and the second PTRS port can be associated with the second TRP (i.e., the first indicated TCI state). The lowest indexed DMRS port within the DMRS ports corresponding to the second indicated TCI state).

[Two port PTRS in SFN-mode DMRS transmission]

For SFN-style DMRS transmission, the same REs can correspond to two different TCI states. That is, the same DMRS ports can be used simultaneously in two TRPs and the DMRS can experience multiple channels. In this situation, considering two PTRS ports transmitted in an SFN fashion, channel estimation can be based on a composite channel and the same REs can be associated with two PTRS ports with two different indicated TCI states. Since there is, it may not provide many advantages to the UE. To avoid having two PTRS ports associated with the same REs with two different TCI states, PTRS can be transmitted in a TRP specific manner while DMRS and PDSCH can be transmitted in a SFN manner. In this type of situation, the first PTRS port can be associated with the lowest indexed DMRS port within the DMRS port corresponding to the first TRP (i.e., the first indicated TCI status), and the second PTRS port can be associated with the second TRP (i.e., the second indicated TCI status). TCI state) may be associated with a pre-determined/pre-configured indexed DMRS port within the DMRS ports corresponding to the The RE association information for the second PTRS port may be RRC configured or dynamically indicated in the UE, or may be a DMRS port indexed second lowest. The association of PTRS and two TCI states transmitted from two TRPs may be comb or TD-OCC. This may allow the UE to independently estimate the corresponding phase noise of each TRP. However, since the DMRS is transmitted in an SFN manner and the channel estimation is based on composite channels, separate phase tracking for each TRP can be associated with high complexity for UE implementation. One possible UE implementation could be tap based phase noise compensation where the phase noise of each TRP can be estimated and compensated for the corresponding channel tap. That is, in the HST-SFN scenario, channel modeling can be based on the line of sight (LOS) propagation path of each TRP.

A signal transmitted from TRP _i in HST-SFN scenarios in the time domain can be expressed as in [Equation 1] below.

A signal transmitted from TRP _i may be expressed as [Equation 2] below in the frequency domain.

는 TRP_i의 위상 노이즈이고,

는 부반송파 k에서 송신된 데이터이다.

는 HST-SFN 시나리오들에서 2가지 TRP들 모두에 대하여 동일할 수 있다. [수학식 2]는 아래 [수학식 3]과 같이 요약될 수 있다.In [Equation 2],

is the phase noise of TRP _i ,

is data transmitted on subcarrier k.

may be the same for both TRPs in HST-SFN scenarios. [Equation 2] can be summarized as [Equation 3] below.

는 TRP_i의 CPE(common phase error)이고, 아래 [수학식 4]에 의해서 도출될 수 있다.In [Equation 3],

Is the common phase error (CPE) of TRP _i , and can be derived by Equation 4 below.

The second term of the summation in [Equation 2] and [Equation 3] is the ICI part due to the channel variation within the OFDM symbol, which may be caused by a phase noise error. The signal received by the UE may be derived by [Equation 5] below in the frequency domain.

은 가산(additive) 백색 가우시안(Gaussian) 노이즈이다. ICI 부분이 가산 노이즈로 처리되고

에 포함되는 경우, 수신된 신호는 아래 [수학식 6]과 같이 단순하게 표현될 수 있다.In [Equation 5],

is the additive white Gaussian noise. The ICI part is treated as additive noise and

When included in , the received signal can be simply expressed as in [Equation 6] below.

일 수 있다. 그러나, [수학식 5] 및 [수학식 6]과 같이, 위상-노이즈 보상은 TRP-특정 채널 추정에 관련될 수 있다. 이러한 이슈를 해소하기 위하여, UE 수신기의 구현은 탭-기반 위상-노이즈 보상 기술을 포함할 수 있다.22 is a block diagram illustrating a UE receiver 2200 for demodulating and decoding received data. UE receiver 2200 comprises timing synchronization unit 2201, CP-OFDM demodulation block 2202, channel estimation block 2203, phase noise estimation and compensation block 2204, MIMO, connected as shown in FIG. A detection block 2205 and a decoding block 2206 may be included. Different functional blocks of UE receiver 220 may be provided by modules and/or circuits. The channel estimation block 2203 can estimate the channel based on the received DMRS, and since the DMRS is transmitted in an SFN manner, the channel estimation can be based on a composite channel. That is, the channel estimated in the frequency domain is obtained when the received signal is equalized.

can be However, as shown in [Equation 5] and [Equation 6], phase-noise compensation may be related to TRP-specific channel estimation. To address this issue, the implementation of the UE receiver may include a tap-based phase-noise compensation technique.

Modeling of propagation channels in HST-SFN scenarios can be based on the LOS propagation path of TRPs. In HST-SFN scenarios with two TRPs, the channel can be represented by a 2-tap model in the time domain where each tap corresponds to a LOS path from one TRP. That is, the time domain channel model may be as shown in [Equation 7] below.

)이고,

는 시간-도메인 분해능으로 양자화된 탭 지연이며,

는 CP를 포함하는 심볼 기간이다. 즉, 도 22의 채널 추정 블록(2203)은 시간 도메인에서 채널 구조가 TRP마다 탭-기반이므로 복합 채널을 추정할 수 있다. 각 TRP에 대하여 추정된 채널(즉,

)은 추정된 복합 채널(즉,

)로부터 가능하게 도출될 수 있다.In [Equation 7], h _i is a complex channel gain corresponding to the line of sight (LOS) propagation path from TRP _i (ie,

)ego,

is the tap delay quantized to time-domain resolution,

is a symbol period including CP. That is, since the channel structure in the time domain is tap-based for each TRP, the channel estimation block 2203 of FIG. 22 can estimate a composite channel. Channel estimated for each TRP (i.e.,

) is the estimated composite channel (i.e.,

) can possibly be derived from

를 시간 도메인으로 취한 다음 시간 도메인 채널의 각 탭(즉, [수학식 7]의

)을 주파수 도메인으로 별도로 취함으로써 TRP-특정 채널 추정을 수행하기 위한 추가 기능 블록에 의해 제공될 수 있다. 이는 UE에서 PTRS에 대한 TRP-특정 등화 및 TRP-특정 CPE 추정을 가능하게 할 수 있다. 이러한 보다 정확한 위상 트래킹은 높은 복잡도의 희생으로 높은 전송량을 가능하게 할 수 있다.This is the estimated channel

is taken as the time domain, and then each tap of the time domain channel (i.e., [Equation 7]

) can be provided by an additional functional block for performing TRP-specific channel estimation by taking separately in the frequency domain. This may enable TRP-specific equalization and TRP-specific CPE estimation for PTRS at the UE. This more accurate phase tracking can enable high throughput at the expense of high complexity.

23 is a block diagram illustrating a UE receiver 2300 according to an exemplary embodiment of the present disclosure. The UE receiver 2300 comprises a timing synchronization unit 2301, CP-OFDM demodulation block 2302, channel estimation block 2303, TRP-specific channel estimation block 2304, phase synchronization unit 2301, connected as shown in FIG. It may include a noise estimation and compensation block 2305 , a MIMO detection block 2306 and a decoding block 2307 . Different functional blocks of UE receiver 2300 may be provided by modules and/or circuits.

For FR2 (ie, frequency band of 24.25 GHz to 52.6 GHz) applications, an example UE implementation may be to use two different panels so that the UE controls the corresponding beam of each TRP independently. That is, separate transmitter/receiver chains can be implemented for multi-TRP transmission in an HST-SFN scenario.

24 is a block diagram illustrating a UE receiver 2400 with separate receiver chains according to an exemplary embodiment of the present disclosure. The UE receiver 2400 includes a timing synchronization unit 2401, a CP-OFDM demodulation block 2402, a channel estimation block 2403 and a phase noise estimation and compensation block 2404 connected as shown in FIG. A timing synchronization unit 2411, a CP-OFDM demodulation block 2212, a channel estimation block 2213 and a phase noise estimation and compensation block 2214 connected as shown in FIG. It may include a second receiver chain including. The outputs of the phase noise estimation and compensation blocks 2404 and 2414 may be provided to a MIMO detection block 2405 and decoding block 2406 as shown in FIG. 24 .

To the UE receiver 2400, the DMRS may be transmitted in an SFN manner, but signals received from each TRP may be processed independently, allowing channel estimation and phase noise compensation to be performed separately for each TRP communication. . The demodulated data corresponding to each TRP can then be combined, equalized and decoded.

[Default Beam Determination in Multi-TRP Transmission]

25 and 26 respectively show single-DCI and multi-DCI M-TRP transmission schemes according to exemplary embodiments of the present disclosure. Multiple transmit and receive points (M-TRP) have been introduced in Rel-15 as a solution to improve cell-edge performance. In the M-TRP transmission scheme, different antenna ports of one or more different channels may be in multiple TRPs, typically non-co-located. M-TRP transmissions can be classified into single-DCI M-TRP category and multi-DCI M-TRP category. For single-DCI M-TRP, a single PDCCH may be transmitted to schedule single or multiple PDSCHs. PDSCH can be transmitted from different TRPs such that different layers are transmitted from different TRPs. Alternatively, all layers of PDSCH can be transmitted from one TRP, while multiple PDSCHs can be multiplexed in the time or frequency domain within the same transport block (TB). In multi-DCI M-TRP transmission, each TRP can transmit its own PDCCH and DCIs. Each DCI can schedule one PDSCH with two-layer transmission. All layers of a given PDSCH can be transmitted from antenna ports within the same TRP.

Different multiplexing schemes may be applied to PDCCH transmission. With TDM multiplexing, two symbol sets of the transmitted PDCCH/(in time) two non-overlapping transmitted PDCCH repetitions/(in time) non-overlapping multi-chance transmitted PDCCH are different TCI states may be associated with With FDM multiplexing, resource element group (REG) bundles/control channel elements (CCEs) of transmitted PDCCH/(in frequency) two non-overlapping transmitted PDCCH repetitions/(in frequency) non-overlapping multi-opportunity Two sets of transmitted PDCCHs may be associated with different TCI states. With SDM (non-transparent SFN), two different DMRS ports can each be associated with one different TCI state. Rel-17 may not support SDM PDCCH schemes. With SFN, PDCCH DMRS can be associated with two TCI states in all REGs/CCEs of PDCCH.

For non-SFN M-TRP PDCCH transmission, non-repetitive, repeatable and multi-chance subsequent possibilities may be considered. For non-repetition, one encoding/rate matching can be used for PDCCH with two TCI states. That is, some specific CCE/REGs of the candidate may be associated with the first TCI state, and the rest of the CCE/REGs may be associated with the second TCI state. In case of repetition, encoding/rate matching can be based on one repetition, and the same coded bits can be repeated for another repetition. Each repetition may have the same number of CCEs and coded bits, and may correspond to the same DCI payload. In case of multi-opportunity, separate DCIs may schedule the same PDSCH/PUSCH/RS/TB, etc. or result in the same.

To enable PDCCH transmission in two different TCI states with any of the transmission schemes described above, one approach may be to associate one control resource set (CORESET) with two different TCI states. . As the different multiplexing schemes for PDCCH transmission described below, schemes A to C described below can be used with one CORESET having two activated TCI states.

27A illustrates Scheme A in which one PDCCH candidate (in a given set of SSs) is associated with both TCI states of CORESET according to an exemplary embodiment of the present disclosure.

27B illustrates scheme B in which two sets of PDCCH candidates (in a given SS set) are associated with two TCI states of CORESET respectively, according to an exemplary embodiment of the present disclosure.

27C shows two sets of PDCCH candidates, both of which are associated with CORESET, and each SS set is associated with only one TCI state of CORESET, according to an exemplary embodiment of the present disclosure. Shows how C is associated with sets.

For scheme B and scheme C, the two cases described below can be considered for mapping between different PDCCH candidates to different TCI states.

Case 1: Two (or more) PDCCH candidates may be explicitly inter-linked (UE may be aware of linking before decoding).

Case 2: Two (or more) PDCCH candidates may not be explicitly linked to each other (UE may not be aware of linking before decoding).

As another way to associate PDCCH candidates to two different TCI states, one SS set can be associated with two different CORESETs, each CORESET associated with a TCI state. Different SS and CORESET multiplexing schemes may make it possible to allow multiple TCI states for PDCCH candidates. In this way, two SS sets can be associated with two CORESETs where each CORESET is configured with a different TCI state.

[Default beam and RS specifications]

In the case of a single DCI-based NCJT in Rel-16, the UE can be configured with up to 3 CORESETs and 10 search space sets in each of up to 4 bandwidth parts (BWPs) in the serving cell. A search space set can be associated with only one CORESET and one TCI state. Having a PDCCH with two TCI states in a multi-TRP scenario may affect the default beam and RS specifications, since the current specification specifies considering one TCI state for CORESET. For purposes of explanation, the default beam for PDSCH may be derived based on the TCI state of the CORESET with the lowest ID. In addition, if not configured, the default spatial relation and pathloss RS may be derived based on the TCI state of the CORESET having the lowest ID or the TCI state having the lowest ID for the PDSCH. In beam-failure recovery, the beam-failure detection RS, if not explicitly configured, may be derived based on the TCI status for the responsive CORESET used to monitor the PDCCH.

The default CTI state of PDSCH can be determined as a single TCI state or a pair of TCI states. A single TCI state may be applicable to PDSCH transmission schemes with single or multiple TCI states, while a pair of TCI states may be applicable only to PDSCH transmission schemes with two different TCI states.

[Single TCI State Default Beam]

To determine default beams for PDSCH repetitions, three methods described below may be possible.

Method 1 (ignoring CORESETs with two TCI states): In general, for multi-TRP scenarios, one solution to avoid ambiguity in the default beam and RS determination at the UE is that the default beam and RS specifications are in a single TCI state. It can be determined based only on CORESETs having . That is, the default beam, default spatial relationship, and pathloss RS for the PDSCH may be derived based on the TCI state of the CORESET having the lowest ID among CORESETs having single TCI states. With method 1, Rel-15 operations can be reused, except that the method only considers CORESETs associated with one TCI state.

Method 2 (CORESET with lowest ID with 2 TCI states is an error): Another solution is that the specification does not allow a lowest CORESET index consisting of 2 TCI states. In this way, the UE will be configured with CORESETs and associated one or two TCI states, such that the CORESET with the lowest ID in the most recent slot for which the UE monitors PDCCHs can be associated with two different TCI states. may not be expected. This may be a reuse of Rel-15 behavior.

Method 3 (Reference TCI-State/TRP): Another approach is that one of the TRPs and/or TCI states corresponding thereto is a reference TRP and/or reference TCI in which a default beam and RS specification are derived based on a specific TCI state. that can be composed of Method 3 will be described later.

로 RRC를 통해 UE를 구성할 수 있다. UE는 레퍼런스 TRP 인덱스

에 연관된 TCI 상태들을 포함하는 CORESET들 중 최저 ID를 가지는 CORESET가 선택될 수 있다. UE가 레퍼런스 TRP 인덱스

로 구성되도록 가정되는 예시가 아래 [표 2]에서 제시된다. 디폴트 TCI 상태는 CORESET ID#2에서 TCI-State 3일 수 있다. [표 2]는 방법3에서 디폴트 TCI 상태 결정의 예시를 나타낸다.Each TCI state may be additionally associated with TRP through TRP index 1 or 2. Each CORESET can be associated with one or two TCI states. In particular, the MAC-CE can activate either a single TCI state or a pair of TCI states (TCI state#1, TCI state#2). gNB is the reference TRP index for default beam determination

The UE can be configured through RRC. UE is the reference TRP index

A CORESET having the lowest ID among CORESETs including TCI states associated with may be selected. UE reference TRP index

An example that is assumed to be configured is presented in [Table 2] below. The default TCI state may be TCI-State 3 in CORESET ID#2. [Table 2] shows an example of default TCI status determination in Method 3.

CORESET ID Activated TCI states #0

TCI-State 1 with

#One TCI-State 2 with

#2 (TCI-State 1 with

, TCI-State 3 with

) #3 (TCI-State 2 with

, TCI-State 5 with

) #4 TCI-State 5 with

#5 TCI-State 4 with

을 가지는 P-튜플(tuple)의 형태로 있을 수 있다. P는 상이한 CPRESET들에 대하여 동일하거나 상이할 수 있다(

). gNB는 레퍼런스 TCI 상태 인덱스

로 UE를 구성할 수 있다. 인덱스

를 포함하는 TCI 개시 튜플을 가지는 CORESET들 중, 최저 ID를 가지는 CORESET가 선택될 수 있다. 그 다음에 디폴트 TCI 상태는 선택된 CORESET에 연관된 튜플의

-엔트리일 수 있다.Method 4 (CORESET-independent reference TCI state entry index): Method 4 may include the concept of an undefined reference TRP. In this way, the UE can be configured with TCI states without explicit association between TCI states and TRPs. MAC-CE can activate one or two TCI states for each CORESET. Activated TCI states are P entries

It may be in the form of a P-tuple with P may be the same or different for different CPRESETs (

). gNB is the reference TCI state index

UE can be configured with index

Among CORESETs having a TCI start tuple including , a CORESET having the lowest ID may be selected. Then the default TCI state is the number of tuples associated with the selected CORESET.

-Can be an entry.

가 레퍼런스 TCI 상태로서 각 CORESET에서 미리 결정된 TCI 상태(예컨대, 첫번째 또는 두번째)를 상시 고려하도록 특정될 수 있다.Alternatively, the reference TCI entry index

may be specified to always consider a predetermined TCI state (eg, first or second) in each CORESET as a reference TCI state.

로 UE를 구성할 수 있다. UE는 적어도 2개의 TCI 상태들을 가지는 CORESET로부터 디폴트 TCI 상태를 결정할 수 있다(즉, 활성화된 튜플은 2이상의 길이일 수 있다). 두번째 엔트리는 그러한 CORESET들 중 디폴트 TCI 상태들로서 선택될 수 있다.For example, gNB

UE can be configured with The UE may determine a default TCI state from a CORESET having at least 2 TCI states (ie, an activated tuple may be of length 2 or more). The second entry can be selected as default TCI states among those CORESETs.

로서 레퍼런스 TCI 상태 인덱스를 구성하는 경우 방법4에 의해서 실현될 수 있다. 방법4는 아래와 같이 다르게 설명될 수 있다.The default beam can also always be determined from the CORESET with the lowest CORESET ID, regardless of the number of active TCT states in the CORESET, the configuration of the reference TRP or the TCI-state index, etc. This means that gNB

In the case of configuring the reference TCI state index as , it can be realized by method 4. Method 4 can be differently explained as follows.

번째 TCI 상태로 결정될 수 있다.

는 레퍼런스 TCI 상태 인덱스로서 RRC를 통해 UE에 구성될 수 있거나, 미리 결정될 수 있다. 각 CORESET에서 미리 결정된 TCI 상태(예컨대, 첫번째 또는 두번째 상태)를 레퍼런스 TCI 상태로서 항시 고려하도록 특정될 수 있다. 다르게는, 레퍼런스 인덱스가 각 CORESET 별로 구성될 수 있다.Method 4-0 (special case of Method 4): The default TCI state can always be determined from the CORESET with the lowest CORESET ID. If CORESET has a single TCI state, the TCI state may be determined as a default TCI state. If CORESET has multiple TCI states, the default TCI state is

It may be determined as the second TCI state.

Can be configured to the UE via RRC as a reference TCI state index, or can be predetermined. In each CORESET, it may be specified to always consider a predetermined TCI state (eg, first or second state) as a reference TCI state. Alternatively, a reference index may be configured for each CORESET.

을 갖는 P-튜플의 형태일 수 있다. P는 상이한 CORESET들에서 동일하거나 상이할 수 있다(

). gNB는 각 CORESET에 대하여 레퍼런스 TCI 상태 인덱스

로 UE를 구성할 수 있다. 그 다음에 디폴트 TCI 상태는 최저 CORESET ID를 가지는 CORESET의 TCI 상태들로부터 선택될 수 있다. 디폴트 TCI 상태는

가 선택된 CORESET의 레퍼런스 TCI 상태 인덱스인 선택된 CORESET와 연관된 튜플의

-엔트리일 수 있다.Method 5 (CORESET-dependent reference TCI state entry index): In this method, the UE can be configured with TCI states without explicit association between TCI states and TRPs. MAC-CE can activate one or more TRI states for each CORESET. Activated TCI states are P entries

It may be in the form of a P-tuple with P may be the same or different in different CORESETs (

). gNB is the reference TCI state index for each CORESET

UE can be configured with A default TCI state can then be selected from the TCI states of the CORESET with the lowest CORESET ID. The default TCI state is

of the tuple associated with the selected CORESET, where is the reference TCI state index of the selected CORESET.

-Can be an entry.

An HST SFN transmission may be a coherent joint transmission using only one PDCCH to allocate a set of PDSCH resources. That is, the same PDCCH can be simultaneously transmitted from several TRPs. From the UE point of view, additional DL transmissions can be interpreted as additional DL delay-spread components from a single TRP. Having a PDCCH with two TCI states in the HST scenario may mean that CORESET of Rel-17 can be configured with two TCI states. In the HST scenario, the default beam and RS specifications may follow the Rel-16 operation using the TCI state of the PDCCH transmitted from the reference TRP. The reference TRP may be a TRP used by the gNB as a reference for frequency offset compensation in a TRP-based frequency offset precompensation scheme. This may make the reference TRP the primary TRP, especially in case of beam failure events. The reference TRP may be semi-statically indicated to the UE with some TCI state, and the default TCI state may be selected from among the CORESETs with the lowest ID with the TCI state associated with the reference TRP. Another approach is that one of the TCI states in the CORESET can be semi-statically indicated to the UE as the reference TCI state, or it can be specified to always consider a pre-determined TCI state (ie first or second) as the reference TCI state in each CORESET. can Then, the reference TCI state can be used as the default TCI state to determine the default beam and RS. Another solution is that the default beam and RS specifications are determined based only on the CORESET with a single TCI state, or the specification can ensure that the lowest CORESET index always has a single TCI state in an HST scenario.

The TCI state format can contain two different pairs of QCL information and reference signals, as shown in bold below.

With this new advanced Rel-17 TCI format, PDCCH with two TCI states in HST scenario can be associated with CORESET with one TCI state. Accordingly, the default beam and RS specifications can comply with Rel-16 operation and can be derived based on the TCI state of the CORESET with the lowest ID. However, the TCI state of the CORESET with the lowest ID may contain two pairs of QCL RSs, causing ambiguity in the default beam and RS decision in the UE. To address this issue, one solution is that the default beam and RS specifications can be determined based only on a CORESET with a TCI state containing only a pair of QCL information (ie, legacy TCI). Alternatively, the specification may restrict the lowest CORESET index in an HST scenario to always have a legacy TCI state other than the advanced Rel-17 format. Another approach may be that one of the QCL information pairs or one of the QCL RSs in the TCI state of the CORESET with the lowest ID may be semi-statically indicated to the UE as a reference QCL information pair or reference QCL RS. In addition, it may be specified to always consider a predetermined (ie, first or second) QCL information pair/QCL RS in each TCI state as a reference for use as a default beam and RS. Another approach may be to semi-statically indicate the reference TRP to the UE as a pair of QCL information, and select the default beam and RS among the CORESETs with the lowest ID with the TCI state associated with the reference TRP.

Different PDCCH schemes can be considered to provide increased reliability of PDCCH transmission in multi-TRP cells, especially in scenarios where TRP is likely to be blocked. Different PDCCH schemes have been presented, in which schemes the PDCCH can repeat within or across different SS sets. In addition, multiple PDCCHs may be transmitted in a manner called multi-chance to schedule the same PDSCH/PUSCH or UL/DL channel/signal. From another point of view, a repeated PDCCH may be associated with one or two CORESETs. As an example, the PDCCH may repeat over or within a set of synchronization signals (SS). As another example, the PDCCH may be transmitted such that the first repetition is transmitted on the first SS associated with CORESET #1 and the second repetition is transmitted on the second SS set associated with CORESET #2. 28A-28D show examples of iterative schemes according to exemplary embodiments of the present disclosure.

With one CORESET and two TCI states, the default PDCSH beam may be determined based on the TCI state of the CORESET associated with the most recent repetition of the PDCCH in the slot.

Method 6 (Latest TCI status associated with repeated PDCCHs within the same CORESET): In this way, each CORESET can be associated with one or two TCI statuses. In particular, the MAC-CE is a single TCI state for CORESET, or a pair of TCI states #1 and #2 corresponding to the first and second TRPs, respectively, in cases where the activated TCI state indicates a TRP number that can be associated. TCI states (TCI state # 1, TCI state # 2) of can be activated. A default TCI state can be selected from the CORESET with the lowest ID associated with the two different TCI states. Among two TCI states of CORESET having the lowest ID, a TCI state associated with the most recent SS set may be selected as a default TCI state.

Method 7 (Latest TCI state associated with repeated PDCCHs with different CORESETs): In this method, each CORESET can be associated with one or two TCI states. In particular, the MAC-CE is a single TCI state for CORESET if the MAC-CE also activates a TRP number to which this TCI state can be associated, or as long as TCI states #1 and #2 correspond to the first and second TRPs, respectively. You can activate the TCI state of a pair. The default TCI state can be selected in CORESET with the lowest ID.

When CORESET is associated with two different TCI states. The TCI state associated with the most recent SS set is selected as the default TCI state among the two TCI states of the CORESET with the lowest ID.

If a CORESET is associated with a single TCI state and is linked to a linked CORESET, the default TCI state may be selected as either the COERSET or the linked CORESET, whichever ends in the later slot.

Alternatively, either method 6 or method 7 may be modified and used so that the fastest SS set among the linked sets is selected.

[Two TCI State Default Beams]

As mentioned above, the default beam may also be determined as a pair of TCI states.

A default pair of TCI states can be determined from a configured CORESET with two different TCI states.

Method 8 (default TCI state pair and CORESET-dependent): If the UE is configured with one or more CORESETs, at least one of which can be associated with two TCI states, the default TCI state of the PDSCH can be determined as follows . The UE may determine the CORESET with the lowest ID among the CORESETs associated with the two TCI states. A default TCI state can be determined as a pair of TCI states associated with the CORESET with the lowest CORESET ID.

Method 8 can be applied if there is at least one CORESET with two different TCI states. If there is no CORESET with two TCI states, the default beam may be determined as the TCI state of the CORESET with the lowest CORESET ID.

Alternatively, the default TCI state may be determined to be selected from a single or pair of TCI state sets activated by the MAC-CE for PDSCH reception.

Method 9 (default TCI state pair and lowest PDSCH codepoint): Default TCI of PDSCH if MAC CE activates TCI state set for PDSCH reception so there can be at least one TCI codepoint with two different TCI states The state may be determined as the TCI state corresponding to the lowest TCI codepoint among TCI codepoints comprising two different TCI states.

[Apply TCI status for PDSCH]

If the UE determines the default TCI state pair as (A, B), if the PDSCH follows the default TCI state, the UE shall apply the TCI state (A, B) according to the mapping. However, prior to DCI decoding, the UE may not know which resource was used for each TCI state in the PDSCH transmission. In the following, a solution to solve this problem will be provided.

[SDM, SFN and HST PDSCH]

In the SDM PDSCH scheme, a certain number of ports of the PDSCH may be associated with a first TCI state, and certain other ports may be associated with a second TCI state. Accordingly, regardless of time/frequency domain resource allocation, a UE can be expected to receive an OFDM symbol with two TCI states without requiring DCI decoding. Similar to SFN and HST PDSCH, a DMRS port may be associated with two TCI states and the UE may not need resource allocation to apply the TCI state.

[TDM PDSCH]

With TDM PDSCH, the UE may need to know the resource allocation in order to apply the default TCI state. As one solution, the DCI decoding delay can be checked by defining the DCI decoding delay time. The UE may receive a symbol before the DCI decoding delay in the first TCI state and may receive the next symbol according to the resource allocation indicated in the DCI. The methods described below may define UE behavior. In the following methods, "default TCI state threshold time" may be defined according to UE capability, and may be measured from the end of the PDCCH scheduling the PDSCH.

이 주어질 수 있다. UE는 디폴트 TCI 상태를 (A, B)로 결정할 수 있고 후술되는 바와 같이 심볼을 수신할 수 있다.Method 10 (one state up to DCI decoding delay and two states up to threshold): the UE is configured with an RRC parameter indicating reception of a PDSCH with two default TCI states, and at least one TCI codepoint corresponds to two TCI states , and if the UE is configured to receive a single-DCI M-TRP TDM PDSCH, the UE is configured via RRC or predefined DCI decoding delay

this can be given The UE may determine the default TCI state as (A, B) and may receive symbols as described below.

까지, UE는 첫번째 TCI 상태 A를 가정하여 심볼을 수신할 수 있다. 종료 후

부터 CORESET의 디폴트 TCI 상태 임계 시간까지, UE는 TCI 상태 A 및 B 모두에서 DCI가 나타내는 시간 도메인 자원 할당에 따라 심볼을 수신할 수 있다.After the end of CORESET from the first symbol of CORESET in which the UE monitors the PDCCH

Until , the UE may receive a symbol assuming the first TCI state A. after end

From to the default TCI state threshold time of CORESET, the UE can receive symbols according to the time domain resource allocation indicated by the DCI in both TCI states A and B.

29 shows an example of PDSCH scheduling and UE operation according to method 10. From the start of the PDCCH to the second vertical dashed line 2901, the UE can receive symbols with the first TCI state 2902 from the second vertical dashed line 2901, and the UE will receive symbols according to the time domain resource indicated in the DCI. can The time domain resource can direct the UE to receive PDSCH opportunities, as shown in FIG. 29 , so the UE will be able to recognize receiving a second PDSCH opportunity with second TCI state 2903 .

In method 10, the UE may receive a symbol before the DCI decoding delay in a single TCI state. This can prevent the gNB from scheduling two TCI states before the DCI decoding delay. This problem can be solved in Method 11.

Method 11 (Two States Up to DCI Decoding Delay and Two States Up to Threshold): FIG. 30 shows Method 11 according to an exemplary embodiment of the present disclosure. If the UE is configured with an RRC parameter indicating reception of a PDSCH with two default TCI states, at least one TCI codepoint indicates two TCI states, and the UE is configured to receive a single-DCI M-TRP TDM PDSCH , the UE may be configured via RRC or given a predefined DCI decoding delay T_(DCI decoding). The UE may determine the default TCI state as (A, B) and may receive symbols as described below.

까지, 심볼이 첫번째 및 두번째 TCI 상태에 맵핑되는 고정된 시간 위치들에 따라 첫번째 TCI 상태 A 및 두번째 TCI 상태 B를 가정하여 심볼을 수신할 수 있다. CORESET 종료 후

부터 디폴트 TCI 상태 임계 시간까지, UE는 TCI 상태 A 및 B 모두에서 DCI가 지시하는 시간 도메인 자원 할당에 따라 심볼을 수신할 수 있다.After the end of CORESET from the first symbol of CORESET in which the UE monitors the PDCCH

Until , the symbol may be received assuming the first TCI state A and the second TCI state B according to fixed time positions at which the symbol is mapped to the first and second TCI states. After CORESET ends

From to the default TCI state threshold time, the UE can receive symbols according to the time domain resource allocation indicated by the DCI in both TCI states A and B.

Alternatively, the UE may receive only one TCI state before the threshold or two TCI states at a fixed time location.

Method 12 (one state up to threshold): the UE is configured with an RRC parameter indicating reception of PDSCH with two default TCI states, at least one TCI codepoint indicates two TCI states, and the UE is single-DCI When configured to receive the M-TRP TDM PDSCH, the UE may determine the default TCI state as (A, B) and receive symbols with TCI states as described below.

31 illustrates method 12 according to an exemplary embodiment of the present disclosure. From the first symbol of CORESET to the default TCI state threshold time, the UE can receive symbols of TCI state A.

Method 13 (Two States to Threshold): FIG. 32 illustrates Method 13 according to an exemplary embodiment of the present disclosure. If the UE is configured with an RRC parameter indicating reception of a PDSCH with two default TCI states, at least one TCI codepoint indicates two TCI states, and the UE is configured to receive a single-DCI M-TRP TDM PDSCH, The UE may determine a default TCI state as (A, B) and may receive a symbol with TCI states as described below.

From the first symbol of CORESET to the default TCI state threshold time, the UE can receive a symbol with both TCI states A and B according to the fixed time positions at which the symbols are mapped to the first and second TCI states.

[Default TCI status for PDSCH in HST-SFN]

Having two separate radio resource control (RRC) parameters to configure the SFN-type physical downlink control channel (PDCCH) and the SFN-type physical downlink shared channel (PDSCH), in particular, when the scheduling offset is less than the threshold timeDurationForQCL in FR2 or PDSCH If reception is scheduled with DCI without a TCI field in FR1 or FR2, it may cause ambiguity in the default TCI state for PDSCH in the UE.

In order to solve the above-mentioned problem, if the time offset between the reception of the downlink (DL) DCI and the corresponding PDSCH in FR2 is less than the threshold value timeDurationForQCL (regardless of whether the TCI state field is present in the DCI or not), and the PDSCH is SFN When RRC is configured using the method, PDSCH is RRC configured using the SFN method, PDSCCH is configured as SFN, and enableTwoDefaultTCIStates is configured, the default TCI state for PDSCH reception is the lowest MAC CE among those having two TCI states. (control element) may be two TCI states of a codepoint.

When the time offset between receptions of the DL DCI and the corresponding PDSCH at FR2 is less than the threshold timeDurationForQCL (regardless of whether or not the TCI status field is present in the DCI), the PDSCH is RRC configured using the SFN scheme, and the PDCCH is configured using the SFN scheme It is configured using, and when enableTwoDefaultTCIStates is not configured, the default TCI state for PDSCH reception may be determined based on the existing CORESET having a single TCI state. Alternatively, the default TCI state for PDSCH reception may be constrained to always have a single TCI state. Another approach is that one of the TCI states in the CORESET may be predetermined or semi-statically indicated to the UE as a default beam and a reference TCI state used to determine the TCI state. Another approach is that the reference TRP may be pre-determined or semi-statically indicated to the UE and the default TCI state for PDSCH reception may be selected from the CORESET with the lowest identifier (ID) with the TCI state associated with the reference TRP. .

In FR2, the time offset between the receptions of the DL DCI and the corresponding PDSCH is less than the threshold timeDurationForQCL (whether or not the TCI status field is present in the DCI) and the PDSCH is RRC configured using the SFN scheme and the PDCCH is not SFN configured. No, and if enableTwoDefaultTCIStates is not configured, the default TCI state for PDSCH reception may be two TCI states of the lowest MAC CE codepoint among MAC CE codepoints having two TCI states.

If the time offset between the receptions of the DL DCI and the corresponding PDSCH at FR2 is less than the threshold timeDurationForQCL (regardless of whether the TCI status field is present in the DCI or not), the PDSCH is RRC configured using the SFN scheme, and the PDCCH is SFN configured If not, and enableTwoDefaultTCIStates is not configured, the default TCI state for PDSCH reception is Rel. It can be determined based on the TCI state of the lowest CORESET index similar to 16 operation.

In FR2, the time offset between the receptions of the DL DCI and the corresponding PDSCH is less than the threshold timeDurationForQCL (whether or not the TCI status field is present in the DCI), the PDSCH is not RRC configured using the SFN scheme, and the PDCCH is SFN , the default TCI state for PDSCH reception may be determined based on the first TCI state having the lowest CORESET ID in the latest slot.

In FR2, the time offset between the receptions of the DL DCI and the corresponding PDSCH is less than the threshold timeDurationForQCL (whether or not the TCI status field is present in the DCI), the PDSCH is not RRC configured using the SFN scheme, and the PDCCH is SFN If not configured, the default TCI state for PDSCH reception may be one active TCI state of the CORESET with the lowest controlResourceSetId in the latest slot.

In FR2, when the time offset between the DL DCI and the corresponding PDSCH is greater than the threshold timeDurationForQCL, the TCI state field does not exist in the DCI, the PDSCH is RRC configured in the SFN method, the PDCCH is configured as SFN, and enableTwoDefaultTCIStates is configured, PDSCH reception The default TCI state for can be two TCI states of CORESET scheduling.

In FR2, the time offset between the reception of the DL DCI and the corresponding PDSCH is greater than the threshold timeDurationForQCL, the TCI state field does not exist in the DCI, the PDSCH is RRC configured in SFN mode, the PDCCH is SFN configured, and enableTwoDefaultTCIStates is not configured. If not, the default TCI state for PDSCH reception may be determined based on one of the TCI states of scheduling CORESET. To this end, one of the TCI states in CORESET may be predetermined or semi-statically indicated to the UE as a reference TCI state used to determine a default TCI state for PDSCH reception. Alternatively, the reference TRP may be predetermined or semi-statically indicated to the UE, and a default TCI state may be selected as the TCI state associated with the reference TRP.

In some embodiments, a new RRC parameter may be introduced to indicate the number of configurable default TCI states if no TCI state field is present in the DCI. There may be two different cases for the new RRC parameter: If two default TCI states can be configured for the UE, the default TCI state for PDSCH reception can be two TCI states scheduling CORESET. Alternatively, when only one default TCI state is configurable, the default TCI state for PDSCH reception may be determined based on one of the TCI states of scheduling CORESET. To this end, one of the TCI states in CORESET may be predetermined or semi-statically indicated to the UE as a reference TCI state used to determine a default TCI state for PDSCH reception. Alternatively, the reference TRP may be predetermined or semi-statically indicated to the UE, and a default TCI state may be selected as the TCI state associated with the reference TRP.

In a situation where the PDCCH is not configured as an SFN, PDSCH reception can be performed using a single beam in which the default TCI state for PDSCH reception is the scheduling CORESET TCI state. Another approach may be that the default TCI state for PDSCH reception is determined based on the two TCI states of the lowest MAC CE codepoint of the MAC CE codepoints having the two TCI states. Another approach may be that the default TCI state is the TCI state of the scheduling CORESET and the second one is determined from the lowest CORESET index. To this end, when the lowest CORESET index in the HST scenario has a single TCI state, the single TCI state may be used as the second default TCI state for PDSCH reception. Otherwise, when the lowest CORESET index in an HST scenario has two TCI states, one of the TCI states in the CORESET is either predetermined to the UE as a reference TCI state used to determine the second default TCI state for PDSCH reception, or It can be displayed semi-statically. Alternatively, the reference TRP may be predetermined or semi-statically indicated to the UE, and the second default TCI state of PDSCH reception may be selected from the CORESET with the lowest ID having a TCI state associated with the reference TRP.

If the PDSCH is not RRC-configured in the SFN scheme and the PDCCH is SFN-configured, the default TCI state for PDSCH reception may be determined based on one of the TCI states of the scheduling CORESET. To this end, one of the TCI states in CORESET may be predetermined or semi-statically indicated to the UE as a reference TCI state used to determine a default TCI state for PDSCH reception. Alternatively, the reference TRP may be predetermined or semi-statically indicated to the UE, and a default TCI state may be selected to be related to the reference TRP.

If the PDSCH is not RRC-configured in the SFN scheme and the PDCCH is not SFN-configured, the default TCI state for PDSCH reception may be an active TCI state of CORESET having the lowest controlResourceSetId in the latest slot.

However, in FR1, there may be no reporting of the timeDurationForQCL threshold by the UE. If the TCI state field does not exist in the DCI, default TCI states for PDSCH reception in the HST SFN scenario can be derived as follows.

When PDSCH is RRC configured using SFN scheme and PDCCH is SFN configured by RRC, default TCI states for PDSCH reception may be two TCI states of CORESET scheduling.

When PDSCH is RRC-configured using SFN scheme and PDCCH is SFN-configured by RRC, the default TCI state for PDSCH reception is two TCI states of the lowest MAC CE codepoint among MAC CE codepoints having two TCI states. can be determined based on Another approach is that the first default TCI state for PDSCH reception can be the TCI states of the scheduling CORESET and the second one can be determined from the lowest CORESET index. To this end, when the lowest CORESET index in the HST scenario has a single TCI state, the single TCI state may be used as the second default TCI state for PDSCH reception. Otherwise, if the lowest CORESET index in the HST scenario has two TCI states, one of the TCI states of the CORESET may be predetermined or semi-statically indicated to the UE as a reference TCI state used to determine the second default. there is. TCI status for PDSCH reception. Alternatively, the reference TRP may be predetermined or semi-statically indicated to the UE, and the second default TCI state of PDSCH reception may be selected from the CORESET with the lowest ID having a TCI state associated with the reference TRP.

If the PDSCH is not RRC-configured by the SFN scheme and the PDCCH is SFN-configured by the RRC, the default TCI state for PDSCH reception may be determined based on one of the TCI states of the scheduling CORESET. To this end, one of the TCI states in CORESET may be predetermined or semi-statically indicated to the UE as a reference TCI state used to determine a default TCI state for PDSCH reception. Alternatively, the reference TRP may be predetermined or semi-statically indicated to the UE, and a default TCI state may be selected as being associated with the reference TRP.

If the PDSCH is not RRC configured by the SFN method and the PDCCH is not SFN configured by the RRC, the default TCI state for PDSCH reception may be an active TCI state of CORESET having controlResourceSetId in the lowest latest slot.

37 is a flowchart of an exemplary embodiment of a method 3700 for determining a default TCI state for a UE in a wireless communication network. The method 3700 of FIG. 37 can begin at step 3701. At step 3702, the UE may determine that wireless communication is being conducted in FR2. At step 3703, the UE may receive one or more CORESETs carrying PDCCH with DCI. At step 3704, the UE may determine that the time offset between receptions by the UE of the DCI and the corresponding PDSCH is less than a predetermined time threshold. At step 3705, the UE may determine that the PDSCH is configured in SFN scheme. At step 3706, the UE may determine that no option is configured to enable the two default TCI states for the UE. In step 3707, the UE may determine whether the PDCCH is configured in SFN scheme. In step 3708, based on whether the PDCCH is configured in the SFN scheme, the UE may determine a default TCI state for PDSCH reception. At step 3709, the UE may receive the PDSCH using the determined default TCI state.

In one embodiment of method 3700, the UE can determine that the PDCCH is configured in SFN fashion, and the default TCI state for the PDSCH can be determined based on one or more of the CORESETs with a single TCI state. In one embodiment of method 3700, the UE may determine that the PDCCH is configured in SFN fashion, and the default TCI state for PDSCH reception may be determined based on a reference TCI state selected from the TCI states of the CORESETs. In one embodiment of method 3700, the UE can determine that the PDCCH is not configured in SFN fashion, and the default TCI state for PDSCH reception can be determined based on the TCI state of the CORESET with the lowest CORESET index. there is. In one embodiment of the method 3700, the time offset between the receptions of the DCI and the corresponding PDSCH is the OFDM for the UE to perform the PDCCH and apply spatial quasi-colocation (QCL) information received in the DCI for PDSCH processing ( Orthogonal Frequency-Division Multiplexed) may be shorter than the time duration for the minimum number of symbols.

38 is a flowchart of an exemplary embodiment of a method 3800 for determining a default TCI state for a UE in a wireless communication network. The method 3800 of FIG. 38 can begin at step 3801. At step 3802, the UE may determine that wireless communication is conducted in FR2. At step 3803, the UE may receive one or more CORESETs including scheduling CORESETs carrying PDCCHs with DCI. In step 3804, the UE may determine that the time offset between DCI and receptions by the UE of the corresponding PDSCH is greater than or equal to a predetermined time threshold. At step 3805, the UE may determine that the TCI status indicator is not present in the DCI. In step 3806, the UE may determine whether the PDSCH is configured in SFN scheme. In step 3807, the UE may determine whether the PDCCH is configured in SFN scheme. In step 3808, based on whether the PDSCH is configured in the SFN manner and whether the PDCCH is configured in the SFN manner, the UE may determine a default TCI state for PDSCH reception. At step 3809, the UE may receive the PDSCH using the determined default TCI state.

In one embodiment, method 3800 may further include determining that two default TCI states are configurable for the UE if the UE determines that the PDSCH is configured with SFN scheme and the PDCCH is configured with SFN scheme. and the default TCI state for PDSCH reception may be determined to include two TCI states of scheduling CORESET. In one embodiment, the method 3800 further includes the UE determining that only one default TCI state is configurable for the UE, if the UE determines that the PDSCH is configured with SFN scheme and the PDCCH is configured with SFN scheme. may include, and the default TCI state for PDSCH reception may be determined based on one TCI state of scheduling CORESET. In one embodiment of the method 3800, the state of one TCI in the scheduling CORESET may be predetermined or semi-statically indicated to the UE as a reference TCI state used to determine the default TCI state for PDSCH reception.

In one embodiment of the method 3800, the UE can determine that the PDSCH is configured with SFN scheme and the PDCCH is not configured with SFN scheme, and the default TCI state for PDSCH reception is determined based on the TCI state of the scheduling CORESET. It can be, and the UE can receive the PDSCH using a single beam. In one embodiment of the method 3800, the UE can determine that the PDSCH is not configured in SFN fashion and the PDCCH is configured in SFN fashion, and the default TCI state for PDSCH reception determines the default TCI state for PDSCH reception. It can be determined based on the TCI state of the scheduling CORESET that is predetermined or semi-statically indicated to the UE as the reference TCI state to be used. In one embodiment of the method 3800, the UE can determine that the PDSCH is not configured in SFN fashion and the PDCCH is not configured in SFN fashion, and the default TCI state for PDSCH reception is with the lowest controlResourceSetId in the latest slot. It can be determined that the active TCI state of CORESET.

39 is a flowchart of an exemplary embodiment of a method 3900 for determining a default state for a UE in a wireless communication network. The method 3900 of FIG. 39 begins at step 3901. At step 3902, the UE may determine that wireless communication is being conducted in FR1. At step 3903, the UE may receive one or more CORESETs including scheduling CORESETs carrying PDCCHs with DCI. At step 3904, the UE may determine that the TCI status indicator is not present in the DCI. In step 3905, the UE may determine whether the PDSCH is configured in SFN scheme. At step 3906, the UE may determine whether the PDCCH is configured in SFN scheme. In step 3907, based on whether the PDSCH is configured in the SFN scheme and whether the PDCCH is configured in the SFN scheme, the UE may determine a default TCI state for PDSCH reception. At step 3908, the UE may receive the PDSCH using the determined default TCI state.

In one embodiment of method 3900, the UE can determine that the PDSCH is configured in SFN fashion and the PDCCH is configured in SFN fashion, and the default TCI state for PDSCH reception is to include two TCI states of scheduling CORESET. can be judged. In an embodiment of method 3900, the UE can determine that the PDSCH is not configured in SFN fashion and the PDCCH is configured in SFN fashion, and the default TCI state for PDSCH reception is based on the one TCI state of the scheduling CORSET. can be judged. In one embodiment of method 3900, the state of one TCI in the scheduling CORESET may be predetermined or semi-statically indicated to the UE as a reference TCI state used to determine a default TCI state for PDSCH reception. In one embodiment of method 3900, the UE can determine that the PDSCH is not configured in SFN fashion and the PDCCH is not configured in SFN fashion, and the default TCI state for PDSCH reception is with the lowest controlResourceSetId in the latest slot. It can be determined that the active TCI state of CORESET.

[How to determine fixed time positions]

In methods 11 and 13, the fixed time location may be a symbol received by the UE using a specific TCI state among two default states. A “fixed window” may first be determined to determine the time location for each TCI state. A symbol inside a "fixed window" can be assigned to one of two TCI states. The window may start at the first symbol of CORESET and may end at the start of the next earliest CORESET at which the UE monitors the PDCCH, the time indicated by the threshold time or DCI decoding delay, or the time indicated by the default TCI state threshold. there is.

[Case 1: Intra-slot TDM]

For intra-slot TDM, the "fixed window" can start at the start symbol of CORESET and end at the start of the next earliest CORESET or the time indicated by the DCI decoding delay, whichever is earlier. Once the fixed window is determined, the symbols set in the window can be mapped to the first and second TCI states as described below.

일 수 있다. 윈도우에 N개의 심볼들이 있는 슬롯에서 일반적으로

이 선택될 수 있다.Two chunks in each slot: If a slot has N symbols in a fixed window, the first N ₁ symbols can be mapped to the first TCI state and the second NN ₁ symbols can be configured with N ₁ RRC may be mapped to a second TCI state in which N ₁ is RRC configured, pre-fixed, or

can be In slots with N symbols in the window, it is usually

can be selected.

33 illustrates intra-slot TDM according to an exemplary embodiment of the present disclosure.

Multiple contiguous chunks with alternating TCI states: As another approach, if a slot has N symbols in a fixed window, the N symbols can be grouped into L groups, where group1 is the first N ₁ symbols. symbols, group 2 can include the next N ₂ symbols, group 3 can include the next N ₃ symbols, and so on, each group has an even number of symbols except for the first or last group possible. may include For a group with an even number of symbols, the first half of the symbols may be mapped to the first TCI state and the next half may be mapped to the second TCI state. For a group with an odd number of 2K+1 symbols, the first K symbols may be mapped to the first TCI state, and the next K+1 symbols may be mapped to the second TCI state. 34 illustrates multiple contiguous chunks with alternating TCI states with L=2 according to an exemplary embodiment of the present disclosure.

[Case 2: Inter-slot TDM]

A similar scheme to intra-slot can be considered for inter-slot TDM with an alternating change of TCI state in two consecutive slots. For inter-slot TDM, the "fixed window" can start at the start symbol of CORESET and end at the start of the next earliest CORESET or the time indicated by the DCI decoding delay, whichever is earlier. Once the fixed window is determined, the set of symbols in the window can be mapped to the first and second TCI states as described below.

Multiple contiguous slots with alternating TCI state: if N contiguous slots overlap a fixed window, the symbols of the first, third, fifth... slots can be mapped to the first TCI state and the second, fourth, sixth ... symbols of slots may be mapped to the second TCI state. 35 illustrates multiple consecutive slots with alternating TCI states based on inter-slot TDM case 2 according to an exemplary embodiment of the present disclosure.

[FDM PDSCH]

In the FDM PDSCH scheme, the first half of a resource block may be associated with a first TCI state and the next half may be associated with a second TCI state. In principle, the default TCI state and UE behavior for the FDM PDSCH scheme is that the fixed time location can be replaced with a fixed frequency location, and the frequency locations (RBs) can be mapped to the first and second TCI states. A fixed window including a start RB and a length according to the number of RBs may be determined. Alternatively, a fixed window may be defined by a set of bitmaps indicating which RBs are included in the window. If the window is determined to contain N RBs, the first N ₁ RBs may be mapped to the first TCI state, and the second N ₁ RBs may be mapped to the second TCI state.

An example of this method is as described below. A fixed window can be selected as the overall active BWP. An active BWP may be split in half into two sets of equal number of RBs. The UE may receive the first set of RBs with the first TCI state and the second set with the second TCI state until the UE decodes the DCI. After the UE decodes the DCI, the UE may receive the allocated PDSCH RB set according to the frequency domain allocation. To accommodate this behavior, the gNB can be expected to transmit the FDM PDCSH so that the first half of the scheduled RBs are in the first half of the BWP and the next half of the scheduled RBs are in the next half of the BWP. 36 illustrates an FDM PDSCH scheme according to an exemplary embodiment of the present disclosure.

[Sample TP to TS 38.214]

Antenna ports of QCL

In RRC connected mode, regardless of the configuration of tci-PresentInDCI and tci-PresentDCI-1-2, the offset between the reception of the DL DCI and the corresponding PDSCH is less than the threshold timeDurationForQCL, and at least one If the configured TCI state includes qcl-Type set to 'typeD',

- The UE determines the PDCCH QCL of the CORESET associated with the monitored search space having the lowest controlResourceSetID in the most recent slot in which the DM-RS ports of the PDSCH of the serving cell are monitored by the UE for one or more CORESETs within the active BWP of the serving cell. It can be assumed to be in RS(s) and QCL for QCL parameter(s) used for indication. In this case, if the qcl-Type of the PDSCH DM-RS is set to 'typeD' different from the overlapping PDCCH DM-RS type in at least one symbol, the UE is expected to give priority to the reception of the PDCCH associated with the CORESET. It can be. This may also be applied in the case of intra-band CA (when PDSCH and CORESET are in different component carriers).

- If the UE is configured with enableDefaultTCIStatePerCoresetPoolIndex and the UE is configured by higher layer parameter PDCCH-Config containing two different coresetPoolIndex values in different ControlResourceSets,

- The UE, in the most recent slot in which one or more CORESETs associated with the same value of coresetPoolIndex as the PDCCH scheduling the PDSCH within the active BWP of the serving cell are monitored by the UE, DM-RS of the PDSCH associated with the coresetPoolIndex value of the serving cell RS(s) for the QCL parameter(s) used in the PDCCH QCL indication of the CORESET associated with the monitored search space with the lowest controlResourceSetID among the CORESETs for which the port can be configured with the same value of coresetPoolIndex as the PDCCH scheduling the PDSCH. ) and QCL. In this case, if 'QCL-TypeD' of the PDSCH DM-RS overlaps in at least one symbol and is different from the type of the PDCCH DM-RS associated with the same coresetPoolIndex, the UE prioritizes reception of the PDCCH associated with the corresponding CORESET. can be expected to give This may also be applied in the case of intra-band CA (when PDSCH and CORESET are in different component carriers).

- If the UE is set to enableTwoDefaultTCI-States and at least one TCI codepoint indicates two TCI states, the UE assumes that the DM-RS port of the PDSCH or the PDSCH transmission opportunities of the serving cell include two different TCI states. It can be assumed to be in RS(s) and QCL with respect to the QCL parameter(s) associated with the TCI states corresponding to the lowest of the TCI codepoints. If the UE is configured with the higher layer parameter repeatScheme set to 'tdmSchemeA' or configured with the higher layer parameter repeatNumber, the mapping of TCI status to PDSCH transmission opportunity converts the indicated TCI status to the active TCI in the slot with the first PDSCH transmission opportunity. Based on the state, it may be determined according to clause 5.1.2.1 by replacing the indicated TCI states with the TCI states corresponding to the lower of the TCI codepoints comprising two different TCI states. The UE determines that the PDSCH for the set of symbols starting from the first symbol of CORESET in which the scheduling PDCCH is transmitted in N ₃ symbols after the end of CORESET or the DM-RS port of PDSCH transmission cases contains two different TCI states. For the QCL parameter associated with the first TCI state corresponding to the lower of the TCI codepoints, it may be assumed to be in QCL with RS, where N ₃ may be determined according to clause 9.2.3 of TS 38.213. In this case, when 'QCL-TypeD' in both TCI states corresponding to a lower codepoint among TCI codepoints including two different TCI states is different from that of the overlapping PDCCH DM-RS in at least one symbol , the UE can be expected to give priority to the reception of the PDCCH associated with the corresponding CORESET. This may also be applied in the case of intra-band CA (when PDSCH and CORESET are in different component carriers).

- In all of the above cases, if none of the TCI states configured for the serving cell of the scheduled PDSCH is configured with the qcl-Type set to 'typeD', the UE determines the time offset between reception of the DL DCI and the corresponding PDSCH Other QCL assumptions should be obtained from the indicated TCI states for the independently scheduled PDSCH.

<unchanged parts omitted>

[beam failure]

Two different scenarios can be considered to address beam failure recovery in the HST scenario using TRP-based frequency offset precompensation. First, beam failure may occur in the reference TRP, and secondly, beam failure may occur in the non-reference TRP. In both of these scenarios, each TRP can be configured with up to two periodic 1-port CSI-RSs per BWP. DL RS for a new beam identification set may be based on SSB and CSI-RS, and may be explicitly set separately for each TRP. In addition, since two TCIs are activated for the PDCCH, each TCI state may implicitly correspond to the beam failure detection RS for the corresponding TRP if not configured. If a beam error occurs for one of the TRPs, reception at the UE may fall back to a single TRP scenario. That is, when the terminal detects a beam failure, the terminal must switch the channel estimation and other signal processing algorithms to the channel estimation and signal processing algorithm used for single TRP transmission.

In an HST-SFN scenario with TRP-based frequency offset precompensation, if a beam failure occurs for the reference TRP, some QCL information relationship in non-reference TRP transmissions due to the beam failure of the reference TRP (i.e., a Doppler-shift related attribute) ) may break. For clarification, if the network precompensates for frequency offsets for the TRS and all other DL transmissions (including PDCCH, DMRS, and PDSCH), the QCL RS of the TRS transmitted on the non-reference TRP is the type of TRS or QCL transmitted on the reference TRP. It may be the QCL RS of the TRS transmitted from the reference TRP with B. Similarly, if the network precompensates for frequency offsets for all DL transmissions except TRS, the PDSCH DMRS of the non-reference TRP may be the TRS transmitted from the reference TRP with QCL type B. This may mean that beam failure in reference TRP transmission may interfere with PDCCH and PDSCH reception in non-reference TRP. In this case, one solution may be to the QCL information of the latest TRS received from the reference TRP before the beam failure is identified and used for continuation of DL transmission from the non-reference TRP. That is, the UE can monitor only the PDCCH using the TCI state associated with the non-reference TRP, and can reuse the associated TCI state of the reference TRP in the most recently received CORESET before beam failure is identified by the UE. PDSCH reception may also consist of reuse of the associated TCI state of the reference TRP in the latest slot before beam failure is identified by the UE.

Embodiments of the technical ideas and operations described in this specification may be implemented in digital electronic circuits, computer software, firmware, or hardware, including the structures disclosed herein and their structural equivalents, or in a combination of one or more of them. Embodiments of the technical ideas described in this specification may be implemented as one or more computer programs, that is, one or more modules of computer program instructions encoded in a computer storage medium to execute or control operations of data processing. A computer storage medium may be or be included in a computer readable storage device, a computer readable storage substrate, a random or serial access memory array or device, or a combination thereof. A computer storage medium can also be or be included in one or more separate physical components or media (eg, multiple CDs, disks, or other storage devices). In addition, the operations described in this specification may be implemented as operations performed by a data processing device on data stored in one or more computer-readable storage devices or received from other sources.

Although this specification may contain many specific implementation details, implementation details should not be construed as limitations on the scope of the claimed subject matter, but rather as descriptions of features specific to a particular embodiment. Certain features that are described in this specification in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented on multiple embodiments separately or in any suitable subcombination. Moreover, while features may be described above as acting in particular combinations and may even be initially claimed as such, one or more features of a claimed combination may in some cases be removed from the combination and the claimed combination may be a subcombination or subcombination. Can be guided by transformation.

Similarly, while actions are shown in a particular order in the figures, this does not require that those actions be performed in the particular order shown or in a sequential order, or that all of the illustrated acts be performed to achieve a desired result. should not be understood as Multitasking and parallel processing can be advantageous in certain circumstances. Moreover, the separation of various system components in the embodiments described above should not be understood as requiring such separation in all embodiments, and the described program components and systems are generally integrated together into a single software product or multiple software products. It should be understood that it may be packaged into products.

Accordingly, specific embodiments of the technical description have been described herein. Other embodiments are within the scope of the following claims. In some cases, actions recited in the claims may be performed in a different order and still obtain desirable results. Further, the processes depicted in the accompanying drawings do not necessarily require the specific order shown or sequential order to achieve desirable results. Multitasking and parallel processing may be advantageous in certain implementations.

As will be appreciated by those skilled in the art, the innovative concepts described herein may be modified and varied over a wide range of applications. Accordingly, the scope of claimed subject matter should not be limited to the specific example teachings discussed above, but instead is defined by the following claims.

Claims (17)

A method for determining a default transmission configuration indicator (TCI) state for user equipment (UE) in a wireless communication network, comprising:
determining, by the UE, that radio communication is performed in frequency range 2 (FR2);
Receiving, by the UE, at least one control resource set (CORESET) carrying a physical downlink control channel (PDCCH) having downlink control information (DCI);
determining, by the UE, a time offset between receptions by the UE of the DCI and a corresponding physical downlink shared channel (PDSCH);
determining, by the UE, that the PDSCH is configured in a single frequency network (SFN) scheme;
determining, by the UE, that an option to activate two default TCI states for the UE is not configured;
determining, by the UE, whether the PDCCH is configured in an SFN scheme;
determining, by the UE, a default TCI state for PDSCH reception based on whether the PDCCH is configured in an SFN scheme; and
and receiving, by the UE, the PDSCH using the determined default TCI state. The method of claim 1,
If the UE determines that the PDCCH is configured in an SFN scheme, the default TCI state for receiving the PDSCH is determined based on the one or more CORESETs having a single TCI state. The method of claim 1,
When the UE determines that the PDCCH is not configured in the SFN scheme, the default TCI state for receiving the PDSCH is determined based on a reference TCI state selected from TCI states of the one or more CORESETs. . The method of claim 1,
If the UE determines that the PDCCH is not configured in an SFN scheme, the default TCI state for receiving the PDSCH is determined based on a TCI state of a CORESET having a lowest CORESET indicator. The method of claim 1,
The time offset between receptions by the UE of the DCI and the corresponding PDSCH is such that the UE performs PDCCH reception and applies spatial quasi-colocation (QCL) information received in the DCI for PDSCH processing. characterized in that the time duration for the minimum number of orthogonal frequency-division multiplexed (OFDM) symbols for A method for determining a default transmission configuration indicator (TCI) state for user equipment (UE) in a wireless communication network, comprising:
determining, by the UE, that radio communication is performed in frequency range 2 (FR2);
Receiving, by the UE, one or more CORESETs including a scheduling control resource set (CORESET) carrying a physical downlink control channel (PDCCH) having downlink control information (DCI);
determining, by the UE, that a time offset between receptions by the UE of the DCI and a corresponding physical downlink shared channel (PDSCH) is greater than or equal to a predetermined time threshold;
determining, by the UE, that a TCI state does not exist in the DCI;
determining, by the UE, whether the PDSCH is configured in a single frequency network (SFN) scheme;
determining, by the UE, whether the PDCCH is configured in an SFN scheme;
determining, by the UE, a default TCI state for PDSCH reception based on whether the PDSCH is configured in the SFN scheme and whether the PDCCH is configured in the SFN scheme; and
and receiving, by the UE, the PDSCH using the determined default TCI state. The method of claim 6,
determining, by the UE, that two default TCI states are configurable for the UE;
Characterized in that when the UE determines that the PDSCH is configured in the SFN scheme and the PDCCH is configured in the SFN scheme, it is determined that the default TCI state for the PDSCH reception includes two TCI states of the scheduling CORESET. How to. The method of claim 6,
determining, by the UE, that only one default TCI state is configurable for the UE;
When the UE determines that the PDSCH is configured in an SFN manner and the PDCCH is configured in an SFN manner, the default TCI state for receiving the PDSCH is determined based on one TCI state of the scheduling CORESET. How to. The method of claim 8,
The one TCI state of the scheduling CORESET is predetermined or semi-statically indicated to the UE as a reference TCI state to be used to determine the default TCI state for the PDSCH reception. The method of claim 6,
When the UE determines that the PDSCH is configured in the SFN scheme and the PDCCH is not configured in the SFN scheme, the default TCI state for the PDSCH reception is a reference to be used to determine the default TCI state for the PDSCH reception. characterized in that it is determined based on the TCI status of the scheduling CORESET, which is predetermined or semi-statically indicated to the UE as the TCI status. The method of claim 6,
If the UE determines that the PDSCH is not configured in the SFN scheme and the PDCCH is configured in the SFN scheme, the default TCI state for the PDSCH reception is the reference TCI to be used to determine the default TCI state for the PDSCH reception. characterized in that it is determined based on the TCI status of the scheduling CORESET, which is predetermined or semi-statically indicated to the UE as a status. The method of claim 6,
If the UE determines that the PDSCH is not configured in the SFN scheme and the PDCCH is not configured in the SFN scheme, the default TCI state for receiving the PDSCH is the active TCI state of CORESET having the lowest controlResourceSetId in the latest slot. A method characterized in that it is determined to be. A method for determining a default transmission configuration indicator (TCI) state for user equipment (UE) in a wireless communication network, comprising:
determining, by the UE, that radio communication is performed in frequency range 1 (FR1);
receiving, by the UE, one or more CORESETs including a scheduling CORESET carrying a physical downlink control channel (PDCCH) having downlink control information (DCI);
determining, by the UE, that a TCI state does not exist in the DCI;
determining, by the UE, whether a physical downlink shared channel (PDSCH) is configured in a single frequency network (SFN) scheme;
determining, by the UE, whether the PDCCH is configured in an SFN scheme;
determining, by the UE, a default TCI state for PDSCH reception based on whether the PDSCH is configured in the SFN scheme and whether the PDCCH is configured in the SFN scheme; and
and receiving, by the UE, the PDSCH using the determined default TCI state. The method of claim 13,
When the UE determines that the PDSCH is configured in an SFN scheme and the PDCCH is configured in an SFN scheme, it is determined that the default TCI state for receiving the PDSCH includes two TCI states of the scheduling CORESET. How to. The method of claim 13,
When the UE determines that the PDSCH is not configured in the SFN method and the PDCCH is configured in the SFN method, the default TCI state for the PDSCH reception is determined based on one TCI state of the scheduling CORESET. How to. The method of claim 15
Wherein the one TCI state of the scheduling CORESET is predetermined or semi-statically indicated to the UE as a reference TCI state to be used to determine the default TCI state for the PDSCH reception. The method of claim 16
If the UE determines that the PDSCH is not configured in the SFN scheme and the PDCCH is not configured in the SFN scheme, the default TCI state for receiving the PDSCH is the active TCI state of CORESET having the lowest controlResourceSetId in the latest slot. A method characterized in that it is determined to be.

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