WO2023193229A1

WO2023193229A1 - Methods and apparatus of tci state determination for dmrs ports

Info

Publication number: WO2023193229A1
Application number: PCT/CN2022/085773
Authority: WO
Inventors: Yi Zhang; Wei Ling; Chenxi Zhu; Bingchao LIU; Lingling Xiao
Original assignee: Lenovo Beijing Ltd
Current assignee: Lenovo Beijing Ltd
Priority date: 2022-04-08
Filing date: 2022-04-08
Publication date: 2023-10-12
Anticipated expiration: 2024-10-08

Abstract

Methods and apparatus of TCI state determination for DMRS ports are disclosed. The apparatus includes: a receiver that receives a configuration for DMRS that supports a first DMRS port set and a second DMRS port set, wherein the receiver further receives a signalling indicating one or more DMRS ports from at least one of the first and second DMRS port sets and a signalling indicating two TCI states; and a processor that determines a TCI state, from the two indicated TCI states, for each of the indicated DMRS ports based on corresponding DMRS port set and/or CDM group of the indicated DMRS ports.

Description

METHODS AND APPARATUS OF TCI STATE DETERMINATION FOR DMRS PORTS

FIELD

The subject matter disclosed herein relates generally to wireless communication and more particularly relates to, but not limited to, methods and apparatus of TCI state determination for DMRS ports.

BACKGROUND

The following abbreviations and acronyms are herewith defined, at least some of which are referred to within the specification:

Third Generation Partnership Project (3GPP) , 5th Generation (5G) , New Radio (NR) , 5G Node B (gNB) , Long Term Evolution (LTE) , LTE Advanced (LTE-A) , E-UTRAN Node B (eNB) , Universal Mobile Telecommunications System (UMTS) , Worldwide Interoperability for Microwave Access (WiMAX) , Evolved UMTS Terrestrial Radio Access Network (E-UTRAN) , Wireless Local Area Networking (WLAN) , Orthogonal Frequency Division Multiplexing (OFDM) , Single-Carrier Frequency-Division Multiple Access (SC-FDMA) , Downlink (DL) , Uplink (UL) , User Equipment (UE) , Network Equipment (NE) , Radio Access Technology (RAT) , Receive or Receiver (RX) , Transmit or Transmitter (TX) , Physical Downlink Control Channel (PDCCH) , Physical Downlink Shared Channel (PDSCH) , Physical Broadcast Channel (PBCH) , Code-Division Multiplexing (CDM) , Control Resource Set (CORESET) , Cyclic redundancy check (CRC) , Channel State Information (CSI) , Channel State Information Reference Signal (CSI-RS) , Downlink Control Information (DCI) , Demodulation Reference Signal (DMRS, or DM-RS) , Frequency-Division Multiplexing (FDM) , Index/Identifier (ID) , Modulation Coding Scheme (MCS) , Multiple Input Multiple Output (MIMO) , Multi-User MIMO (MU-MIMO) , Orthogonal Cover Code (OCC) , Physical Resource Block (PRB) , Resource Element (RE) , Radio Network Temporary Identifier (RNTI) , Transmission and Reception Point (TRP) , Component Carrier (CC) , Cell Radio Network Temporary Identifier (C-RNTI) , Configured Scheduling RNTI (CS-RNTI) , Frequency Range 1 (FR1) , Frequency Range 2 (FR2) , Synchronization Signal (SS) , Transmission Configuration Indication (TCI) , Technical Specification (TS) , Physical resource block group (PRG) , Quasi Co-Location (QCL) , Phase-Tracking Reference Signal (PT-RS) , Synchronization Signals and Physical Broadcast Channel (SS/PBCH) .

In wireless communication, such as a Third Generation Partnership Project (3GPP) mobile network, a wireless mobile network may provide a seamless wireless communication service to a wireless communication terminal having mobility, i.e., user equipment (UE) . The wireless mobile network may be formed of a plurality of base stations and a base station may perform wireless communication with the UEs.

The 5G New Radio (NR) is the latest in the series of 3GPP standards which supports very high data rate with lower latency compared to its predecessor LTE (4G) technology. Two types of frequency range (FR) are defined in 3GPP. Frequency of sub-6 GHz range (from 450 to 6000 MHz) is called FR1 and millimeter wave range (from 24.25 GHz to 52.6 GHz) is called FR2. The 5G NR supports both FR1 and FR2 frequency bands.

Enhancements on multi-TRP/panel transmission including improved reliability and robustness with both ideal and non-ideal backhaul between these TRPs (Transmit Receive Points) are studied. A TRP is an apparatus to transmit and receive signals, and is controlled by a gNB through the backhaul between the gNB and the TRP.

It is important to identify and specify necessary enhancements for both downlink and uplink MIMO for facilitating the use of large antenna array, not only for FR1 but also for FR2 to fulfil the request for evolution of NR deployments in Release 18.

SUMMARY

Methods and apparatus of TCI state determination for DMRS ports are disclosed.

According to a first aspect, there is provided an apparatus, including: a receiver that receives a configuration for DMRS that supports a first DMRS port set and a second DMRS port set, wherein the receiver further receives a signalling indicating one or more DMRS ports from at least one of the first and second DMRS port sets and a signalling indicating two TCI states; and a processor that determines a TCI state, from the two indicated TCI states, for each of the indicated DMRS ports based on corresponding DMRS port set and/or CDM group of the indicated DMRS ports.

According to a second aspect, there is provided an apparatus, including: a transmitter that transmits a configuration for DMRS that supports a first DMRS port set and a second DMRS port set, wherein the transmitter further transmits a signalling indicating one or more DMRS ports from at least one of the first and second DMRS port sets and a signalling indicating two TCI states; and a processor that determines a TCI state, from the two indicated TCI states, for each of the indicated DMRS ports based on corresponding DMRS port set and/or CDM group of the indicated DMRS ports.

According to a third aspect, there is provided a method, including: receiving, by a receiver, a configuration for DMRS that supports a first DMRS port set and a second DMRS port set, wherein the receiver further receives a signalling indicating one or more DMRS ports from at least one of the first and second DMRS port sets and a signalling indicating two TCI states; and determining, by a processor, a TCI state, from the two indicated TCI states, for each of the indicated DMRS ports based on corresponding DMRS port set and/or CDM group of the indicated DMRS ports.

According to a fourth aspect, there is provided a method, including: transmitting, by a transmitter, a configuration for DMRS that supports a first DMRS port set and a second DMRS port set, wherein the transmitter further transmits a signalling indicating one or more DMRS ports from at least one of the first and second DMRS port sets and a signalling indicating two TCI states; and determining, by a processor, a TCI state, from the two indicated TCI states, for each of the indicated DMRS ports based on corresponding DMRS port set and/or CDM group of the indicated DMRS ports.

BRIEF DESCRIPTION OF THE DRAWINGS

A more particular description of the embodiments will be rendered by reference to specific embodiments illustrated in the appended drawings. Given that these drawings depict only some embodiments and are not therefore considered to be limiting in scope, the embodiments will be described and explained with additional specificity and details through the use of the accompanying drawings, in which:

Figure 1 is a schematic diagram illustrating a wireless communication system in accordance with some implementations of the present disclosure;

Figure 2 is a schematic block diagram illustrating components of user equipment (UE) in accordance with some implementations of the present disclosure;

Figure 3 is a schematic block diagram illustrating components of network equipment (NE) in accordance with some implementations of the present disclosure;

Figure 4A is a schematic diagram illustrating an example of OCC based CDM schemes for Type 1 DMRS in accordance with some implementations of the present disclosure.

Figure 4B is a schematic diagram illustrating an example of OCC based CDM schemes for Type 2 DMRS in accordance with some implementations of the present disclosure.

Figure 5A is a schematic diagram illustrating an example of FDM based CDM schemes for Type 1 DMRS in accordance with some implementations of the present disclosure.

Figure 5B is a schematic diagram illustrating an example of FDM based CDM schemes for Type 2 DMRS in accordance with some implementations of the present disclosure.

Figure 6 is a flow chart illustrating steps of TCI state determination for DMRS ports by UE in accordance with some implementations of the present disclosure; and

Figure 7 is a flow chart illustrating steps of TCI state determination for DMRS ports by gNB in accordance with some implementations of the present disclosure.

DETAILED DESCRIPTION

As will be appreciated by one skilled in the art, aspects of the embodiments may be embodied as a system, an apparatus, a method, or a program product. Accordingly, embodiments may take the form of an all-hardware embodiment, an all-software embodiment (including firmware, resident software, micro-code, etc. ) or an embodiment combining software and hardware aspects.

Furthermore, one or more embodiments may take the form of a program product embodied in one or more computer readable storage devices storing machine readable code, computer readable code, and/or program code, referred to hereafter as “code. ” The storage devices may be tangible, non-transitory, and/or non-transmission.

Reference throughout this specification to “one embodiment, ” “an embodiment, ” “an example, ” “some embodiments, ” “some examples, ” or similar language means that a particular feature, structure, or characteristic described is included in at least one embodiment or example. Thus, instances of the phrases “in one embodiment, ” “in an example, ” “in some embodiments, ” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment (s) . It may or may not include all the embodiments disclosed. Features, structures, elements, or characteristics described in connection with one or some embodiments are also applicable to other embodiments, unless expressly specified otherwise. The terms “including, ” “comprising, ” “having, ” and variations thereof mean “including but not limited to, ” unless expressly specified otherwise.

An enumerated listing of items does not imply that any or all of the items are mutually exclusive, unless expressly specified otherwise. The terms “a, ” “an, ” and “the” also refer to “one or more” , and similarly items expressed in plural form also include reference to one or multiple instances of the item, unless expressly specified otherwise.

Throughout the disclosure, the terms “first, ” “second, ” “third, ” and etc. are all used as nomenclature only for references to relevant devices, components, procedural steps, and etc. without implying any spatial or chronological orders, unless expressly specified otherwise. For example, a “first device” and a “second device” may refer to two separately formed devices, or two parts or components of the same device. In some cases, for example, a “first device” and a “second device” may be identical, and may be named arbitrarily. Similarly, a “first step” of a method or process may be carried or performed after, or simultaneously with, a “second step. ”

It should be understood that the term “and/or” as used herein refers to and includes any and all possible combinations of one or more of the associated listed items. For example, “A and/or B” may refer to any one of the following three combinations: existence of A only, existence of B only, and co-existence of both A and B. The character “/” generally indicates an “or” relationship of the associated items. This, however, may also include an “and” relationship of the associated items. For example, “A/B” means “A or B, ” which may also include the co-existence of both A and B, unless the context indicates otherwise.

Furthermore, the described features, structures, or characteristics of the embodiments may be combined in any suitable manner. In the following description, numerous specific details are provided, such as examples of programming, software modules, user selections, network transactions, database queries, database structures, hardware modules, hardware circuits, hardware chips, etc., to provide a thorough understanding of embodiments. One skilled in the relevant art will recognize, however, that embodiments may be practiced without one or more of the specific details, or with other methods, components, materials, and so forth. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of an embodiment.

Aspects of various embodiments are described below with reference to schematic flowchart diagrams and/or schematic block diagrams of methods, apparatuses, systems, and program products. It will be understood that each block of the schematic flowchart diagrams and/or schematic block diagrams, as well as combinations of blocks in the schematic flowchart diagrams and/or schematic block diagrams, may be implemented by code. This code may be provided to a processor of a general-purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions executed via the processor of the computer or other programmable data processing apparatus create a means for implementing the functions or acts specified in the schematic flowchart diagrams and/or schematic block diagrams.

The code may also be stored in a storage device that can direct a computer, other programmable data processing apparatus, or other devices to function in a particular manner, such that the instructions stored in the storage device produce an article of manufacture including instructions which implement the function or act specified in the schematic flowchart diagrams and/or schematic block diagrams.

The schematic flowchart diagrams and/or schematic block diagrams in the Figures illustrate the architecture, functionality, and operation of possible implementations of different apparatuses, systems, methods, and program products according to various embodiments. In this regard, each block in the schematic flowchart diagrams and/or schematic block diagrams may represent a module, segment, or portion of code, which includes one or more executable instructions of the code for implementing the specified logical function (s) . One skilled in the relevant art will recognize, however, that the flowchart diagrams need not necessarily be practiced in the sequence shown and are able to be practiced without one or more of the specific steps, or with other steps not shown.

It should also be noted that, in some alternative implementations, the functions noted in the identified blocks may occur out of the order noted in the Figures. For example, two blocks shown in succession may, in fact, be substantially executed in concurrence, or the blocks may sometimes be executed in reverse order, depending upon the functionality involved.

Figure 1 is a schematic diagram illustrating a wireless communication system. It depicts an embodiment of a wireless communication system 100. In one embodiment, the wireless communication system 100 may include a user equipment (UE) 102 and a network equipment (NE) 104. Even though a specific number of UEs 102 and NEs 104 is depicted in Figure 1, one skilled in the art will recognize that any number of UEs 102 and NEs 104 may be included in the wireless communication system 100.

The UEs 102 may be referred to as remote devices, remote units, subscriber units, mobiles, mobile stations, users, terminals, mobile terminals, fixed terminals, subscriber stations, user terminals, apparatus, devices, user device, or by other terminology used in the art.

In one embodiment, the UEs 102 may be autonomous sensor devices, alarm devices, actuator devices, remote control devices, or the like. In some other embodiments, the UEs 102 may include computing devices, such as desktop computers, laptop computers, personal digital assistants (PDAs) , tablet computers, smart phones, smart televisions (e.g., televisions connected to the Internet) , set-top boxes, game consoles, security systems (including security cameras) , vehicle on-board computers, network devices (e.g., routers, switches, modems) , or the like. In some embodiments, the UEs 102 include wearable devices, such as smart watches, fitness bands, optical head-mounted displays, or the like. The UEs 102 may communicate directly with one or more of the NEs 104.

The NE 104 may also be referred to as a base station, an access point, an access terminal, a base, a Node-B, an eNB, a gNB, a Home Node-B, a relay node, an apparatus, a device, or by any other terminology used in the art. Throughout this specification, a reference to a base station may refer to any one of the above referenced types of the network equipment 104, such as the eNB and the gNB.

The NEs 104 may be distributed over a geographic region. The NE 104 is generally part of a radio access network that includes one or more controllers communicably coupled to one or more corresponding NEs 104. The radio access network is generally communicably coupled to one or more core networks, which may be coupled to other networks, like the Internet and public switched telephone networks. These and other elements of radio access and core networks are not illustrated, but are well known generally by those having ordinary skill in the art.

In one implementation, the wireless communication system 100 is compliant with a 3GPP 5G new radio (NR) . In some implementations, the wireless communication system 100 is compliant with a 3GPP protocol, where the NEs 104 transmit using an OFDM modulation scheme on the DL and the UEs 102 transmit on the uplink (UL) using a SC-FDMA scheme or an OFDM scheme. More generally, however, the wireless communication system 100 may implement some other open or proprietary communication protocols, for example, WiMAX. The present disclosure is not intended to be limited to the implementation of any particular wireless communication system architecture or protocol.

The NE 104 may serve a number of UEs 102 within a serving area, for example, a cell (or a cell sector) or more cells via a wireless communication link. The NE 104 transmits DL communication signals to serve the UEs 102 in the time, frequency, and/or spatial domain.

Communication links are provided between the NE 104 and the

UEs

102a, 102b, 102c, and 102d, which may be NR UL or DL communication links, for example. Some UEs 102 may simultaneously communicate with different Radio Access Technologies (RATs) , such as NR and LTE. Direct or indirect communication link between two or more NEs 104 may be provided.

The NE 104 may also include one or more transmit receive points (TRPs) 104a. In some embodiments, the network equipment may be a gNB 104 that controls a number of TRPs 104a. In addition, there is a backhaul between two TRPs 104a. In some other embodiments, the network equipment may be a TRP 104a that is controlled by a gNB.

Communication links are provided between the

NEs

104, 104a and the

UEs

102, 102a, respectively, which, for example, may be NR UL/DL communication links. Some

UEs

102, 102a may simultaneously communicate with different Radio Access Technologies (RATs) , such as NR and LTE.

In some embodiments, the UE 102a may be able to communicate with two or more TRPs 104a that utilize a non-ideal or ideal backhaul, simultaneously. A TRP may be a transmission point of a gNB. Multiple beams may be used by the UE and/or TRP (s) . The two or more TRPs may be TRPs of different gNBs, or a same gNB. That is, different TRPs may have the same Cell-ID or different Cell-IDs. The terms “TRP” and “transmitting-receiving identity” may be used interchangeably throughout the disclosure.

Figure 2 is a schematic block diagram illustrating components of user equipment (UE) according to one embodiment. A UE 200 may include a processor 202, a memory 204, an input device 206, a display 208, and a transceiver 210. In some embodiments, the input device 206 and the display 208 are combined into a single device, such as a touchscreen. In certain embodiments, the UE 200 may not include any input device 206 and/or display 208. In various embodiments, the UE 200 may include one or more processors 202 and may not include the input device 206 and/or the display 208.

The processor 202, in one embodiment, may include any known controller capable of executing computer-readable instructions and/or capable of performing logical operations. For example, the processor 202 may be a microcontroller, a microprocessor, a central processing unit (CPU) , a graphics processing unit (GPU) , an auxiliary processing unit, a field programmable gate array (FPGA) , or similar programmable controller. In some embodiments, the processor 202 executes instructions stored in the memory 204 to perform the methods and routines described herein. The processor 202 is communicatively coupled to the memory 204 and the transceiver 210.

The memory 204, in one embodiment, is a computer readable storage medium. In some embodiments, the memory 204 includes volatile computer storage media. For example, the memory 204 may include a RAM, including dynamic RAM (DRAM) , synchronous dynamic RAM (SDRAM) , and/or static RAM (SRAM) . In some embodiments, the memory 204 includes non-volatile computer storage media. For example, the memory 204 may include a hard disk drive, a flash memory, or any other suitable non-volatile computer storage device. In some embodiments, the memory 204 includes both volatile and non-volatile computer storage media. In some embodiments, the memory 204 stores data relating to trigger conditions for transmitting the measurement report to the network equipment. In some embodiments, the memory 204 also stores program code and related data.

The input device 206, in one embodiment, may include any known computer input device including a touch panel, a button, a keyboard, a stylus, a microphone, or the like. In some embodiments, the input device 206 may be integrated with the display 208, for example, as a touchscreen or similar touch-sensitive display.

The display 208, in one embodiment, may include any known electronically controllable display or display device. The display 208 may be designed to output visual, audio, and/or haptic signals.

The transceiver 210, in one embodiment, is configured to communicate wirelessly with the network equipment. In certain embodiments, the transceiver 210 comprises a transmitter 212 and a receiver 214. The transmitter 212 is used to transmit UL communication signals to the network equipment and the receiver 214 is used to receive DL communication signals from the network equipment.

The transmitter 212 and the receiver 214 may be any suitable type of transmitters and receivers. Although only one transmitter 212 and one receiver 214 are illustrated, the transceiver 210 may have any suitable number of transmitters 212 and receivers 214. For example, in some embodiments, the UE 200 includes a plurality of the transmitter 212 and the receiver 214 pairs for communicating on a plurality of wireless networks and/or radio frequency bands, with each of the transmitter 212 and the receiver 214 pairs configured to communicate on a different wireless network and/or radio frequency band.

Figure 3 is a schematic block diagram illustrating components of network equipment (NE) 300 according to one embodiment. The NE 300 may include a processor 302, a memory 304, an input device 306, a display 308, and a transceiver 310. As may be appreciated, the processor 302, the memory 304, the input device 306, the display 308, and the transceiver 310 may be similar to the processor 202, the memory 204, the input device 206, the display 208, and the transceiver 210 of the UE 200, respectively.

In some embodiments, the processor 302 controls the transceiver 310 to transmit DL signals or data to the UE 200. The processor 302 may also control the transceiver 310 to receive UL signals or data from the UE 200. In another example, the processor 302 may control the transceiver 310 to transmit DL signals containing various configuration data to the UE 200.

In some embodiments, the transceiver 310 comprises a transmitter 312 and a receiver 314. The transmitter 312 is used to transmit DL communication signals to the UE 200 and the receiver 314 is used to receive UL communication signals from the UE 200.

The transceiver 310 may communicate simultaneously with a plurality of UEs 200. For example, the transmitter 312 may transmit DL communication signals to the UE 200. As another example, the receiver 314 may simultaneously receive UL communication signals from the UE 200. The transmitter 312 and the receiver 314 may be any suitable type of transmitters and receivers. Although only one transmitter 312 and one receiver 314 are illustrated, the transceiver 310 may have any suitable number of transmitters 312 and receivers 314. For example, the NE 300 may serve multiple cells and/or cell sectors, where the transceiver 310 includes a transmitter 312 and a receiver 314 for each cell or cell sector.

With the increasing need for multiplexing capacity of downlink and uplink demodulation reference signal (DMRS) from various use cases, there is a need for increasing the number of orthogonal ports for DMRS. Based on Release 16 and Release 17 of 3GPP specifications, only 8 orthogonal DMRS ports are supported for type 1 DMRS, and only 12 orthogonal DMRS ports are supported for type 2 DMRS. According to the requirement for increasing DMRS ports, e.g. a maximum of 24 DMRS ports, the TCI state determination schemes may be designed based on not only CDM groups but also DMRS port set.

Downlink DMRS reception procedure is specified in TS 38.214 as follows:

When receiving PDSCH scheduled by DCI format 1_1 by PDCCH with CRC scrambled by C-RNTI, MCS-C-RNTI, or CS-RNTI,

- the UE may be configured with the higher layer parameter dmrs-Type, and the configured DM-RS configuration type is used for receiving PDSCH in as defined in Clause 7.4.1.1 of [4, TS 38.211] .

- the UE may be configured with the maximum number of front-loaded DM-RS symbols for PDSCH by higher layer parameter maxLength given by DMRS-DownlinkConfig.

- if maxLength is set to 'len1' , single-symbol DM-RS can be scheduled for the UE by DCI, and the UE can be configured with a number of additional DM-RS for PDSCH by higher layer parameter dmrs-AdditionalPosition, which can be set to 'pos0' , 'pos1' , 'pos2' or 'pos3' .

- if maxLength is set to 'len2' , both single-symbol DM-RS and double symbol DM-RS can be scheduled for the UE by DCI, and the UE can be configured with a number of additional DM-RS for PDSCH by higher layer parameter dmrs-AdditionalPosition, which can be set to 'pos0' or 'pos1' .

- and the UE shall assume to receive additional DM-RS as specified in Table 7.4.1.1.2-3 and Table 7.4.1.1.2-4 as described in Clause 7.4.1.1.2 of [4, TS 38.211] .

For the UE-specific reference signals generation as defined in Clause 7.4.1.1 of [4, TS 38.211] , a UE can be configured by higher layers with one or two scrambling identity (s) ,

i = 0, 1 which are the same for both PDSCH mapping Type A and Type B.

A UE may be scheduled with a number of DM-RS ports by the antenna port index in DCI format 1_1 as described in Clause 7.3.1.2 of [5, TS 38.212] .

For DM-RS configuration type 1,

- if a UE is scheduled with one codeword and assigned with the antenna port mapping with indices of {2, 9, 10, 11 or 30} in Table 7.3.1.2.2-1 and Table 7.3.1.2.2-2 of Clause 7.3.1.2 of [5, TS 38.212] , or

- if a UE is scheduled with one codeword and assigned with the antenna port mapping with indices of {2, 9, 10, 11 or 12} in Table 7.3.1.2.2-1A and {2, 9, 10, 11, 30 or 31} in Table 7.3.1.2.2-2A of Clause 7.3.1.2 of [5, TS 38.212] , or

- if a UE is scheduled with two codewords,

the UE may assume that all the remaining orthogonal antenna ports are not associated with transmission of PDSCH to another UE.

For DM-RS configuration type 2,

- if a UE is scheduled with one codeword and assigned with the antenna port mapping with indices of {2, 10 or 23} in Table 7.3.1.2.2-3 and Table 7.3.1.2.2-4 of Clause 7.3.1.2 of [5, TS38.212] , or

- if a UE is scheduled with one codeword and assigned with the antenna port mapping with indices of {2, 10, 23 or 24} in Table 7.3.1.2.2-3A and {2, 10, 23 or 58} in Table 7.3.1.2.2-4A of Clause 7.3.1.2 of [5, TS 38.212] , or

- if a UE is scheduled with two codewords,

If a UE receiving PDSCH scheduled by DCI format 1_2 is configured with the higher layer parameter phaseTrackingRS in dmrs-DownlinkForPDSCH-MappingTypeA-DCI-1-2 or dmrs-DownlinkForPDSCH-MappingTypeB-DCI-1-2 or a UE receiving PDSCH scheduled by DCI format 1_0 or DCI format 1_1 is configured with the higher layer parameter phaseTrackingRS in dmrs-DownlinkForPDSCH-MappingTypeA or dmrs-DownlinkForPDSCH-MappingTypeB, the UE may assume that the following configurations are not occurring simultaneously for the received PDSCH:

- any DM-RS ports among 1004-1007 or 1006-1011 for DM-RS configurations type 1 and type 2, respectively are scheduled for the UE and the other UE (s) sharing the DM-RS REs on the same CDM group (s) , and

- PT-RS is transmitted to the UE.

The UE is not expected to simultaneously be configured with the maximum number of front-loaded DM-RS symbols for PDSCH by higher layer parameter maxLength being set equal to 'len2' and more than one additional DM-RS symbol as given by the higher layer parameter dmrs-AdditionalPosition.

The UE is not expected to assume co-scheduled UE (s) with different DM-RS configuration with respect to the actual number of front-loaded DM-RS symbol (s) , the actual number of additional DM-RS, the DM-RS symbol location, and DM-RS configuration type as described in Clause 7.4.1.1 of [4, TS 38.211] .

The UE does not expect the precoding of the potential co-scheduled UE (s) in other DM-RS ports of the same CDM group to be different in the PRG-level grid configured to this UE with PRG =2 or 4.

The UE does not expect the resource allocation of the potential co-scheduled UE (s) in other DM-RS ports of the same CDM group to be misaligned in the PRG-level grid to this UE with PRG=2 or 4.

When receiving PDSCH scheduled by DCI format 1_1, the UE shall assume that the CDM groups indicated in the configured index from Tables 7.3.1.2.2-1, 7.3.1.2.2-1A, 7.3.1.2.2-2, 7.3.1.2.2-2A, 7.3.1.2.2-3, 7.3.1.2.2-3A, 7.3.1.2.2-4, 7.3.1.2.2-4A of [5, TS. 38.212] contain potential co-scheduled downlink DM-RS and are not used for data transmission, where "1" , "2" and "3" for the number of DM-RS CDM group (s) in Tables 7.3.1.2.2-1, 7.3.1.2.2-1A, 7.3.1.2.2-2, 7.3.1.2.2-3, 7.3.1.2.2-3A, 7.3.1.2.2-4, 7.3.1.2.2-4A of [5, TS. 38.212] correspond to CDM group 0, {0, 1} , {0, 1, 2} , respectively.

When receiving PDSCH scheduled by DCI format 1_0, the UE shall assume the number of DM-RS CDM groups without data is 1 which corresponds to CDM group 0 for the case of PDSCH with allocation duration of 2 symbols, and the UE shall assume that the number of DM-RS CDM groups without data is 2 which corresponds to CDM group {0, 1} for all other cases.

The UE is not expected to receive PDSCH scheduling DCI which indicates CDM group (s) with potential DM-RS ports which overlap with any configured CSI-RS resource (s) for that UE.

If the UE receives the DM-RS for PDSCH and an SS/PBCH block in the same OFDM symbol (s) , then the UE may assume that the DM-RS and SS/PBCH block are quasi co-located with 'typeD' , if 'typeD' is applicable. Furthermore, the UE shall not expect to receive DM-RS in resource elements that overlap with those of the SS/PBCH block, and the UE can expect that the same or different subcarrier spacing is configured for the DM-RS and SS/PBCH block in a CC except for the case of 240 kHz where only different subcarrier spacing is supported.

If at least one TCI codepoint indicates two TCI states and the UE receives the DM-RS for PDSCH and an SS/PBCH block in the same OFDM symbol (s) , then the UE may assume that at least one DM-RS port for the PDSCH and SS/PBCH block are quasi co-located with 'QCL-TypeD' , if 'QCL-TypeD' is applicable.

If the UE is configured by higher layer parameter PDCCH-Config that contains two different values of CORESETPoolIndex in different ControlResourceSets, and the UE receives the DM-RS for PDSCH (s) and an SS/PBCH block in the same OFDM symbol (s) , then the UE may assume that at least one DM-RS port for the PDSCH (s) and SS/PBCH block are quasi co-located with 'QCL-TypeD' , if 'QCL-TypeD' is applicable.

If a UE is configured by the higher layer parameter PDCCH-Config that contains two different values of coresetPoolIndex in ControlResourceSet, the UE may be scheduled with fully or partially overlapping PDSCHs in the time and frequency domain by multiple PDCCHs with the following restrictions,

- the UE is not expected to assume different DM-RS configuration with respect to the actual number of front-loaded DM-RS symbol (s) , the actual number of additional DM-RS symbol (s) , the actual DM-RS symbol location, and DM-RS configuration type.

- the UE is not expected to assume DM-RS ports in a CDM group indicated by two TCI states.

When a UE is not indicated with a DCI that DCI field 'Time domain resource assignment' indicating an entry which contains repetitionNumber in PDSCH-TimeDomainResourceAllocation, the UE is not configured with sfnSchemePdsch and it is indicated with two TCI states in a codepoint of the DCI field 'Transmission Configuration Indication' and DM-RS port (s) within two CDM groups in the DCI field 'Antenna Port (s) ' ,

- the first TCI state corresponds to the CDM group of the first antenna port indicated by the antenna port indication table, and the second TCI state corresponds to the other CDM group.

Based on the above 3GPP specification, for single DCI based multiple TRP transmission, CDM group index of DMRS port is used to determine TCI state. For multiple DCI based multiple TRP transmission, restriction of only one TCI state is indicated for DMRS ports in a CDM group.

The TCI state determination schemes are specified in Release16 for single DCI based multiple TRP transmission and multiple DCI based multiple TRP transmission. However, the design is based on a maximum of 8 orthogonal DMRS ports for type 1 DMRS and a maximum of 12 orthogonal DMRS ports for type 2 DMRS.

With increased DMRS ports, the different DMRS resource mapping schemes including CDM, i.e. OCC based multiplexing scheme and FDM based multiplexing schemes may be used. For example, in the case of maxLength=2, DMRS port set 0 may comprise DMRS ports 0-7 for type 1 DMRS and DMRS ports 0-11 for 2 DMRS, and DMRS port set 1 may comprise DMRS ports 8-15 for type 1 DMRS and DMRS ports 12-23 for type 2 DMRS. In the case of maxLength=1, DMRS port set 0 may comprise DMRS ports 0-3 for type 1 DMRS and DMRS ports 0-5 for 2 DMRS, and DMRS port set 1 may comprise DMRS ports 4-7 for type 1 DMRS and DMRS ports 6-11 for type 2 DMRS. Several TCI state determination schemes in the case of large number of DMRS ports (e.g. 16 or 24 DMRS ports in the case of maxLength=2 for

Type

1 or 2 DMRS, respectively; and 8 or 12 DMRS ports in the case of maxLength=1 for

Type

1 or 2 DMRS, respectively) are proposed.

To support flexible MU-MIMO with NCJT transmission, DMRS port from different TRPs may be transmitted from different CDM groups or DMRS port sets if there is no restriction on multiplexing DMRS ports. In this case, TCI state for DMRS ports may be determined by CDM group index and/or DMRS port set index. Also, the DMRS port set index may be implicitly embedded in global CDM group index when FDM based DMRS port multiplexing scheme is used.

For DMRS resource mapping schemes, different DMRS ports can be multiplexed with OCC based CDM schemes or FDM based schemes. Examples of the DMRS resource mapping schemes in the case of maxLength = 2 are provided for illustrative purpose. Figure 4A is a schematic diagram illustrating an example of OCC based CDM schemes for Type 1 DMRS in accordance with some implementations of the present disclosure. Figure 4B is a schematic diagram illustrating an example of OCC based CDM schemes for Type 2 DMRS in accordance with some implementations of the present disclosure. The type 1 DMRS pattern 410 in Figure 4A is illustrated with 24 REs in two bundled PRBs of a OFDM symbol, grouped into two CDM groups, namely CDM group 1 with REs 401 and CDM group 2 with REs 402. Three RE groups may be used for length 4 OCC sequence for DMRS REs in two bundled PRBs. The type 2 DMRS pattern 420 in Figure 4B is illustrated with 12 REs in one PRB of a OFDM symbol, grouped into three CDM groups, namely CDM group 1 with REs 401, CDM group 2 with REs 402, and CDM group 2 with REs 402.

Figure 5A is a schematic diagram illustrating an example of FDM based CDM schemes for Type 1 DMRS in accordance with some implementations of the present disclosure. Figure 5B is a schematic diagram illustrating an example of FDM based CDM schemes for Type 2 DMRS in accordance with some implementations of the present disclosure. The type 1 DMRS pattern 510 of the FDM based scheme in Figure 5A is illustrated with 24 REs in two bundled PRBs of a OFDM symbol, e.g. OFDM symbol 1. The REs in OFDM symbol 1, or OFDM symbol 2, are grouped into four new CDM groups, namely REs 501 for DMRS ports 0-7 in CDM group 1, REs 502 for DMRS ports 8-15 in CDM group 2, REs 503 for DMRS ports 0-7 in CDM group 3, and REs 504 for DMRS ports 8-15 in CDM group 4. The type 2 DMRS pattern 520 of the FDM based scheme in Figure 5B is illustrated with 12 REs in one PRB of a OFDM symbol, e.g. OFDM symbol 1. The REs in OFDM symbol 1, or OFDM symbol 2, are grouped into six CDM groups, namely REs 501 for DMRS ports 0-11 in CDM group 1, REs 502 for DMRS ports 12-23 in CDM group 2, REs 503 for DMRS ports 0-11 in CDM group 3, REs 504 for DMRS ports 12-23 in CDM group 2, REs 505 for DMRS ports 0-11 in CDM group 5, and REs 506 for DMRS ports 12-23 in CDM group 6.

To support flexible MU-MIMO with NCJT transmission, PDSCH for one UE can be transmitted from multiple TRPs and DMRS ports for different UEs can be multiplexed. The DMRS ports for one UE may be from only DMRS port set 0 or 1, or from both DMRS port sets 0 and 1. On account of the large number of DMRS ports, e.g. DMRS ports 8-15 and/or DMRS ports 12-23 are introduced for

type

1 or 2 DMRS in the case of maxLength=2; and DMRS ports 4-7 and/or DMRS ports 6-11 are introduced for

type

1 or 2 DMRS in the case of maxLength=1, various determination schemes are proposed based on DMRS port set and/or CDM group. These schemes are explained in detail based on two possible cases:

Case 1, where DMRS ports may be from both DMRS port sets 0 and 1; and

Case 2, where DMRS ports are from only DMRS port set 0 or 1.

TCI State Determination Based on DMRS Port Set and CDM Group

This TCI state determination scheme is based on Case 1, where DMRS ports may be from both DMRS port sets 0 and 1. With increasing DMRS port number, different multiplexing schemes can be used for DMRS, including OCC based schemes, FDM based schemes, etc. For FDM based schemes, CDM group can be counted separately in each DMRS port set or counted jointly in both DMRS port sets. For separate counting for CDM groups from one DMRS port set, the CDM group number in a DMRS port set is not increased, and the CDM groups with the same index in the different DMRS port sets are distinguished based on DMRS port set. For joint counting for CDM groups from two DMRS port sets, the total CDM group number is increased and indexing scheme needs to be defined. For this scheme, it is proposed for OCC based scheme or FDM based scheme with separate CDM group counting, and it is illustrated with two scenarios: a) single DCI based multiple TRP transmission, and b) multiple DCI based multiple TRP transmission.

Single DCI based multiple TRP transmission

The details for TCI state determination scheme are as follows:

· The first TCI state corresponds to the CDM group and DMRS port set of the first antenna port indicated by the antenna port indication table;

· the second TCI state corresponds to the other CDM group if DMRS ports are from two CDM groups and one DMRS port set;

· the second TCI state corresponds to the other DMRS port set if DMRS ports are from two DMRS port sets and one CDM group; and

· the second TCI state corresponds to the other DMRS port set or the other CDM group if DMRS ports from two DMRS port sets and two CDM groups.

The first TCI state of the two indicated TCI states is used for DMRS ports corresponding to a CDM group and/or DMRS port set of a first indicated antenna port. Where the indicated DMRS ports are from two CDM groups and one DMRS port set, the second TCI state of the two indicated TCI states is used for DMRS ports corresponding to the other CDM group of the two CDM groups. Where the indicated DMRS ports are from two DMRS port sets and one CDM group, the second TCI state of the two indicated TCI states is used for DMRS ports corresponding to the other DMRS port set of the two DMRS port sets. Where the indicated DMRS ports are from two DMRS port sets and two CDM groups, the second TCI state of the two indicated TCI states is used for DMRS ports corresponding to the other DMRS port set of the two DMRS port sets, or the other CDM group of the two CDM groups.

As an example, the mapping scheme between DMRS port and CDM group/DMRS port set is illustrated below for Type 1 DMRS with maxLength=2 based on the antenna port indication table, e.g. Table 1.

Table 1. Mapping relation between DMRS port and CDM group and DMRS port set

DMRS Port index	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15
CDM group index	0	1	1	0	0	1	1	0	0	1	1	0	0	1	1
DMRS Port set index	0	0	0	0	0	0	0	1	1	1	1	1	1	1	1

When two TCI states are indicated in a codepoint of the DCI field 'Transmission Configuration Indication' and DMRS ports {8, 10} are indicated by DCI field “antenna port (s) ” , the TCI state 0 is used for DMRS port 8 and TCI state 1 is used DMRS port 10 based on the proposed scheme for DMRS ports from two CDM groups and one DMRS port set.

When two TCI states are indicated in a codepoint of the DCI field 'Transmission Configuration Indication' and DMRS ports {0, 8} are indicated by DCI field “antenna port (s) ” , the TCI state 0 is used for DMRS port 0 and TCI state 1 is used DMRS port 8 based on the proposed scheme for DMRS ports from two DMRS port sets and one CDM group.

When two TCI states are indicated in a codepoint of the DCI field 'Transmission Configuration Indication' and DMRS ports {2, 8} are indicated by DCI field “antenna port (s) ” , the TCI state 0 is used for DMRS port 2 and TCI state 1 is used DMRS port 8 based on the proposed scheme for DMRS ports from two CDM groups and two DMRS port set.

The examples regarding the mapping scheme between DMRS port and CDM group/DMRS port set are provided for Type 1 DMRS with maxLength=2. The same method and/or principle is also applicable to examples for Type 1 DMRS with maxLength=1, and also for Type 2 DMRS with maxLength=1 or 2.

Multiple DCI based multiple TRP transmission

In this scenario, the restriction may be relaxed as follows to support DMRS ports from different DMRS port sets to be indicated with different TCI states:

· If a UE is configured by the higher layer parameter PDCCH-Config that contains two different values of coresetPoolIndex in ControlResourceSet, the UE is not expected to assume DMRS ports in a CDM group from a DMRS port set indicated by two TCI states.

Thus, upon configuration by higher layer with CORSETs having two different CORESET pool indices, it is not expected to assume DMRS ports in a CDM group from a DMRS port set indicated by two TCI states.

With the proposed restriction, the DMRS ports from different DMRS port sets may be indicated by two TCI states. It may eliminate the scheduling restriction for DMRS ports from different DMRS port sets used for DMRS ports from different TRPs.

TCI state determination based on CDM group

This TCI state determination scheme is based on Case 1, where DMRS ports may be from both DMRS port sets 0 and 1. For this scheme, it is proposed for FDM based scheme with joint CDM group counting. The legacy TCI state determination schemes may be reused based on global CDM group index.

In detail, for single DCI based multiple TRP transmission, the first TCI state corresponds to the CDM group and DMRS port set of the first antenna port indicated by the antenna port indication table, and the second TCI state corresponds to the other CDM group. For multiple DCI based multiple TRP transmission, UE is not expected to assume DMRS ports in a CDM group indicated by two TCI states. The TCI states for the indicated DMRS ports are determined based on the CDM groups with global indices.

The global CDM group index may be defined for all the CDM groups from two DMRS port sets. And, the DMRS port set information is implicitly indicated by the global CDM group index.

In a first indexing scheme, CDM groups are counted by counting firstly CDM groups in one DMRS port set and then CDM groups in another DMRS port set. That is, the global indices of the CDM groups are determined by counting firstly CDM groups in one DMRS port set of the first and second DMRS port sets and then CDM groups in the other DMRS port set.

For example, the mapping schemes between DMRS port and CDM group are defined as shown in Table 2 for Type 1 DMRS, where two CDM groups (CDM groups 2 and 3) from DMRS port set 1 are counted after two CDM groups (CDM groups 0 and 1) from DMRS port set 0. This scheme has good compatibility since CDM group index is not changed for DMRS ports 0-7 relative to the legacy scheme.

Table 2. Mapping relation between DMRS port and CDM group and DMRS port set

DMRS Port index	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15
CDM group index	0	1	1	0	0	1	1	2	2	3	3	2	2	3	3
DMRS Port set index	0	0	0	0	0	0	0	1	1	1	1	1	1	1	1

In a second indexing scheme, the global indices of the CDM groups may be determined by counting firstly one CDM group in each DMRS port set and then another CDM group in each DMRS port set. For example, the mapping schemes between DMRS port and CDM group are defined as shown in Table 3 for Type 1 DMRS, where one CDM group (CDM group 1) from DMRS port set 1 is counted after one CDM group (CDM group 0) from DMRS port set 0; then followed by a second CDM group (CDM group 2) from DMRS port set 0, and a second CDM group (CDM group 3) from DMRS port set 1.

Table 3. Mapping relation between DMRS port and CDM group and DMRS port set

DMRS Port index	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15
CDM group index	0	2	2	0	0	2	2	1	1	3	3	1	1	3	3
DMRS Port set index	0	0	0	0	0	0	0	1	1	1	1	1	1	1	1

In a third indexing scheme, CDM groups are counted based on the order of the first RE index of each CDM group.

For example, the mapping schemes between DMRS port and CDM group are defined as shown in Table 4 for Type 1 DMRS, where

CDM groups

1 and 3 from DMRS port set 1 are counted after

CDM groups

0 and 2 from DMRS port set 0, respectively, based on the order of the first RE index of each CDM group. This scheme is a natural counting scheme but may have compatibility issues since the CDM group index is changed for

DMRS ports

2, 3, 6, and 7 compared with the legacy scheme.

Table 4. Mapping relation between DMRS port and CDM group and DMRS port set

TCI state determination based on legacy scheme and scheduling restriction

This TCI state determination scheme is based on Case 2, where DMRS ports are from only DMRS port set 0 or 1. Scheduling restriction is made for DMRS ports from different DMRS port sets.

In detail, for single DCI based multiple transmission, UE is not expected to be indicated with two TCI states in a codepoint of the DCI field 'Transmission Configuration Indication' when DMRS ports indicated by DCI field “antenna port (s) ” are from different DMRS port sets. For multiple DCI based multiple transmission, UE is not expected to be indicated with different TCI states when DMRS ports indicated by DCI field “antenna port (s) ” are from different DMRS port sets.

In other words, for single DCI and multiple DCI based multiple TRP transmission, DMRS ports indicated by DCI field “antenna port (s) ” are from one single DMRS port set in the case of indicating two different TCI states. With this restriction, the legacy TCI state determination schemes may be reused, with loss of some flexibility.

For example, upon determining that the indicated DMRS ports are from different DMRS port sets, it is not expected to be indicated with two TCI states. The TCI states for the indicated DMRS ports are determined based on CDM group. Upon determining that the indicated DMRS ports are from a same DMRS port set, the TCI states for the indicated DMRS ports are determined based on CDM group.

In another example, upon determining that the indicated DMRS ports are from different DMRS port sets, a first TCI state of the two indicated TCI states is always used for each of the indicated DMRS ports and the second TCI state is ignored. The first TCI state is determined based on a CDM group and/or DMRS port set of a first indicated antenna port.

Figure 6 is a flow chart illustrating steps of TCI state determination for DMRS ports by UE 200 in accordance with some implementations of the present disclosure.

At step 602, the receiver 214 of UE 200 receives a configuration for DMRS that supports a first DMRS port set and a second DMRS port set, wherein the receiver further receives a signalling indicating one or more DMRS ports from at least one of the first and second DMRS port sets and a signalling indicating two TCI states.

At step 604, the processor 202 of UE 200 determines a TCI state, from the two indicated TCI states, for each of the indicated DMRS ports based on corresponding DMRS port set and/or CDM group of the indicated DMRS ports.

Figure 7 is a flow chart illustrating steps of TCI state determination for DMRS ports by gNB 300 in accordance with some implementations of the present disclosure.

At step 702, the transmitter 312 of gNB 200 transmits a configuration for DMRS that supports a first DMRS port set and a second DMRS port set, wherein the transmitter further transmits a signalling indicating one or more DMRS ports from at least one of the first and second DMRS port sets and a signalling indicating two TCI states.

At step 704, the processor 302 of gNB 300 determines a TCI state, from the two indicated TCI states, for each of the indicated DMRS ports based on corresponding DMRS port set and/or CDM group of the indicated DMRS ports.

In one aspect, some items as examples of the disclosure concerning UE for dynamic switching of waveforms may be summarized as follows:

1. An apparatus, comprising:

a receiver that receives a configuration for DMRS that supports a first DMRS port set and a second DMRS port set, wherein the receiver further receives a signalling indicating one or more DMRS ports from at least one of the first and second DMRS port sets and a signalling indicating two TCI states; and

a processor that determines a TCI state, from the two indicated TCI states, for each of the indicated DMRS ports based on corresponding DMRS port set and/or CDM group of the indicated DMRS ports.

2. The apparatus of item 1, wherein a first TCI state of the two indicated TCI states is used for DMRS ports corresponding to a CDM group and/or DMRS port set of a first indicated antenna port.

3. The apparatus of item 2, wherein the indicated DMRS ports are from two CDM groups and one DMRS port set; and a second TCI state of the two indicated TCI states is used for DMRS ports corresponding to the other CDM group of the two CDM groups.

4. The apparatus of item 2, wherein the indicated DMRS ports are from two DMRS port sets and one CDM group; and a second TCI state of the two indicated TCI states is used for DMRS ports corresponding to the other DMRS port set of the two DMRS port sets.

5. The apparatus of item 2, wherein the indicated DMRS ports are from two DMRS port sets and two CDM groups; and a second TCI state of the two indicated TCI states is used for DMRS ports corresponding to the other DMRS port set of the two DMRS port sets, or the other CDM group of the two CDM groups.

6. The apparatus of item 1, wherein upon configuration by higher layer parameter PDCCH-Config that contains two different values of coresetPoolIndex in ControlResourceSet, it is not expected to assume DMRS ports in a CDM group from a DMRS port set indicated by two TCI states.

7. The apparatus of item 1, wherein the TCI states for the indicated DMRS ports are determined based on the CDM groups with global indices.

8. The apparatus of item 7, wherein the global indices of the CDM groups are determined by counting firstly CDM groups in one DMRS port set of the first and second DMRS port sets and then CDM groups in the other DMRS port set.

9. The apparatus of item 7, wherein the global indices of the CDM groups are determined by counting firstly one CDM group in each DMRS port set and then another CDM group in each DMRS port set.

10. The apparatus of item 7, wherein the global indices of the CDM groups are determined by counting according to a first RE index of each CDM group.

11. The apparatus of item 1, wherein upon determining that the indicated DMRS ports are from different DMRS port sets, it is not expected to be indicated with two TCI states.

12. The apparatus of item 11, wherein the TCI states for the indicated DMRS ports are determined based on CDM group.

13. The apparatus of item 1, wherein upon determining that the indicated DMRS ports are from different DMRS port sets, a first TCI state of the two indicated TCI states is used for each of the indicated DMRS ports.

14. The apparatus of item 1, wherein upon determining that the indicated DMRS ports are from a same DMRS port set, the TCI states for the indicated DMRS ports are determined based on CDM group.

15. The apparatus of item 13, wherein the first TCI state is determined based on a CDM group and/or DMRS port set of a first indicated antenna port.

In another aspect, some items as examples of the disclosure concerning gNB for dynamic switching of waveforms may be summarized as follows:

16. An apparatus, comprising:

a transmitter that transmits a configuration for DMRS that supports a first DMRS port set and a second DMRS port set, wherein the transmitter further transmits a signalling indicating one or more DMRS ports from at least one of the first and second DMRS port sets and a signalling indicating two TCI states; and

17. The apparatus of item 16, wherein a first TCI state of the two indicated TCI states is used for DMRS ports corresponding to a CDM group and/or DMRS port set of a first indicated antenna port.

18. The apparatus of item 17, wherein the indicated DMRS ports are from two CDM groups and one DMRS port set; and a second TCI state of the two indicated TCI states is used for DMRS ports corresponding to the other CDM group of the two CDM groups.

19. The apparatus of item 17, wherein the indicated DMRS ports are from two DMRS port sets and one CDM group; and a second TCI state of the two indicated TCI states is used for DMRS ports corresponding to the other DMRS port set of the two DMRS port sets.

20. The apparatus of item 17, wherein the indicated DMRS ports are from two DMRS port sets and two CDM groups; and a second TCI state of the two indicated TCI states is used for DMRS ports corresponding to the other DMRS port set of the two DMRS port sets, or the other CDM group of the two CDM groups.

21. The apparatus of item 16, wherein upon configuration by higher layer parameter PDCCH-Config that contains two different values of coresetPoolIndex in ControlResourceSet, the transmitter transmits a signalling indicating one TCI state for DMRS ports in a CDM group from a DMRS port set.

22. The apparatus of item 16, wherein the TCI states for the indicated DMRS ports are determined based on the CDM groups with global indices.

23. The apparatus of item 22, wherein the global indices of the CDM groups are determined by counting firstly CDM groups in one DMRS port set of the first and second DMRS port sets and then CDM groups in the other DMRS port set.

24. The apparatus of item 22, wherein the global indices of the CDM groups are determined by counting firstly one CDM group in each DMRS port set and then another CDM group in each DMRS port set.

25. The apparatus of item 22, wherein the global indices of the CDM groups are determined by counting according to a first RE index of each CDM group.

26. The apparatus of item 16, wherein upon determining that the indicated DMRS ports are from different DMRS port sets, the transmitter transmits a signalling indicating one TCI state.

27. The apparatus of item 26, wherein the TCI states for the indicated DMRS ports are determined based on CDM group.

28. The apparatus of item 16, wherein upon determining that the indicated DMRS ports are from different DMRS port sets, a first TCI state of the two indicated TCI states is used for each of the indicated DMRS ports.

29. The apparatus of item 16, wherein upon determining that the indicated DMRS ports are from a same DMRS port set, the TCI states for the indicated DMRS ports are determined based on CDM group.

30. The apparatus of item 28, wherein the first TCI state is determined based on a CDM group and/or DMRS port set of a first indicated antenna port.

In a further aspect, some items as examples of the disclosure concerning a method of dynamic switching of waveforms by UE may be summarized as follows:

31. A method, comprising:

receiving, by a receiver, a configuration for DMRS that supports a first DMRS port set and a second DMRS port set, wherein the receiver further receives a signalling indicating one or more DMRS ports from at least one of the first and second DMRS port sets and a signalling indicating two TCI states; and

determining, by a processor, a TCI state, from the two indicated TCI states, for each of the indicated DMRS ports based on corresponding DMRS port set and/or CDM group of the indicated DMRS ports.

32. The method of item 31, wherein a first TCI state of the two indicated TCI states is used for DMRS ports corresponding to a CDM group and/or DMRS port set of a first indicated antenna port.

33. The method of item 32, wherein the indicated DMRS ports are from two CDM groups and one DMRS port set; and a second TCI state of the two indicated TCI states is used for DMRS ports corresponding to the other CDM group of the two CDM groups.

34. The method of item 32, wherein the indicated DMRS ports are from two DMRS port sets and one CDM group; and a second TCI state of the two indicated TCI states is used for DMRS ports corresponding to the other DMRS port set of the two DMRS port sets.

35. The method of item 32, wherein the indicated DMRS ports are from two DMRS port sets and two CDM groups; and a second TCI state of the two indicated TCI states is used for DMRS ports corresponding to the other DMRS port set of the two DMRS port sets, or the other CDM group of the two CDM groups.

36. The method of item 31, wherein upon configuration by higher layer parameter PDCCH-Config that contains two different values of coresetPoolIndex in ControlResourceSet, it is not expected to assume DMRS ports in a CDM group from a DMRS port set indicated by two TCI states.

37. The method of item 31, wherein the TCI states for the indicated DMRS ports are determined based on the CDM groups with global indices.

38. The method of item 37, wherein the global indices of the CDM groups are determined by counting firstly CDM groups in one DMRS port set of the first and second DMRS port sets and then CDM groups in the other DMRS port set.

39. The method of item 37, wherein the global indices of the CDM groups are determined by counting firstly one CDM group in each DMRS port set and then another CDM group in each DMRS port set.

40. The method of item 37, wherein the global indices of the CDM groups are determined by counting according to a first RE index of each CDM group.

41. The method of item 31, wherein upon determining that the indicated DMRS ports are from different DMRS port sets, it is not expected to be indicated with two TCI states.

42. The method of item 41, wherein the TCI states for the indicated DMRS ports are determined based on CDM group.

43. The method of item 31, wherein upon determining that the indicated DMRS ports are from different DMRS port sets, a first TCI state of the two indicated TCI states is used for each of the indicated DMRS ports.

44. The method of item 31, wherein upon determining that the indicated DMRS ports are from a same DMRS port set, the TCI states for the indicated DMRS ports are determined based on CDM group.

45. The method of item 43, wherein the first TCI state is determined based on a CDM group and/or DMRS port set of a first indicated antenna port.

In a yet further aspect, some items as examples of the disclosure concerning a method of dynamic switching of waveforms by gNB may be summarized as follows:

46. A method, comprising:

transmitting, by a transmitter, a configuration for DMRS that supports a first DMRS port set and a second DMRS port set, wherein the transmitter further transmits a signalling indicating one or more DMRS ports from at least one of the first and second DMRS port sets and a signalling indicating two TCI states; and

47. The method of item 46, wherein a first TCI state of the two indicated TCI states is used for DMRS ports corresponding to a CDM group and/or DMRS port set of a first indicated antenna port.

48. The method of item 47, wherein the indicated DMRS ports are from two CDM groups and one DMRS port set; and a second TCI state of the two indicated TCI states is used for DMRS ports corresponding to the other CDM group of the two CDM groups.

49. The method of item 47, wherein the indicated DMRS ports are from two DMRS port sets and one CDM group; and a second TCI state of the two indicated TCI states is used for DMRS ports corresponding to the other DMRS port set of the two DMRS port sets.

50. The method of item 47, wherein the indicated DMRS ports are from two DMRS port sets and two CDM groups; and a second TCI state of the two indicated TCI states is used for DMRS ports corresponding to the other DMRS port set of the two DMRS port sets, or the other CDM group of the two CDM groups.

51. The method of item 46, wherein upon configuration by higher layer parameter PDCCH-Config that contains two different values of coresetPoolIndex in ControlResourceSet, the transmitter transmits a signalling indicating one TCI state for DMRS ports in a CDM group from a DMRS port set.

52. The method of item 46, wherein the TCI states for the indicated DMRS ports are determined based on the CDM groups with global indices.

53. The method of item 52, wherein the global indices of the CDM groups are determined by counting firstly CDM groups in one DMRS port set of the first and second DMRS port sets and then CDM groups in the other DMRS port set.

54. The method of item 52, wherein the global indices of the CDM groups are determined by counting firstly one CDM group in each DMRS port set and then another CDM group in each DMRS port set.

55. The method of item 52, wherein the global indices of the CDM groups are determined by counting according to a first RE index of each CDM group.

56. The method of item 46, wherein upon determining that the indicated DMRS ports are from different DMRS port sets, the transmitter transmits a signalling indicating one TCI state.

57. The method of item 56, wherein the TCI states for the indicated DMRS ports are determined based on CDM group.

58. The method of item 46, wherein upon determining that the indicated DMRS ports are from different DMRS port sets, a first TCI state of the two indicated TCI states is used for each of the indicated DMRS ports.

59. The method of item 46, wherein upon determining that the indicated DMRS ports are from a same DMRS port set, the TCI states for the indicated DMRS ports are determined based on CDM group.

60. The method of item 58, wherein the first TCI state is determined based on a CDM group and/or DMRS port set of a first indicated antenna port.

Various embodiments and/or examples are disclosed to provide exemplary and explanatory information to enable a person of ordinary skill in the art to put the disclosure into practice. Features or components disclosed with reference to one embodiment or example are also applicable to all embodiments or examples unless specifically indicated otherwise.

Embodiments may be practiced in other specific forms. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Claims

An apparatus, comprising:

a receiver that receives a configuration for Demodulation Reference Signal (DMRS) that supports a first DMRS port set and a second DMRS port set, wherein the receiver further receives a signalling indicating one or more DMRS ports from at least one of the first and second DMRS port sets and a signalling indicating two TCI states; and

a processor that determines a Transmission Configuration Indication (TCI) state, from the two indicated TCI states, for each of the indicated DMRS ports based on corresponding DMRS port set and/or Code-Division Multiplexing (CDM) group of the indicated DMRS ports.
The apparatus of claim 1, wherein a first TCI state of the two indicated TCI states is used for DMRS ports corresponding to a CDM group and/or DMRS port set of a first indicated antenna port.
The apparatus of claim 2, wherein the indicated DMRS ports are from two CDM groups and one DMRS port set; and a second TCI state of the two indicated TCI states is used for DMRS ports corresponding to the other CDM group of the two CDM groups.
The apparatus of claim 2, wherein the indicated DMRS ports are from two DMRS port sets and one CDM group; and a second TCI state of the two indicated TCI states is used for DMRS ports corresponding to the other DMRS port set of the two DMRS port sets.
The apparatus of claim 2, wherein the indicated DMRS ports are from two DMRS port sets and two CDM groups; and a second TCI state of the two indicated TCI states is used for DMRS ports corresponding to the other DMRS port set of the two DMRS port sets, or the other CDM group of the two CDM groups.
The apparatus of claim 1, wherein upon configuration by higher layer parameter PDCCH-Config that contains two different values of coresetPoolIndex in ControlResourceSet, it is not expected to assume DMRS ports in a CDM group from a DMRS port set indicated by two TCI states.
The apparatus of claim 1, wherein the TCI states for the indicated DMRS ports are determined based on the CDM groups with global indices.
The apparatus of claim 7, wherein the global indices of the CDM groups are determined by counting firstly CDM groups in one DMRS port set of the first and second DMRS port sets and then CDM groups in the other DMRS port set.
The apparatus of claim 7, wherein the global indices of the CDM groups are determined by counting firstly one CDM group in each DMRS port set and then another CDM group in each DMRS port set.
The apparatus of claim 7, wherein the global indices of the CDM groups are determined by counting according to a first RE index of each CDM group.
The apparatus of claim 1, wherein upon determining that the indicated DMRS ports are from different DMRS port sets, it is not expected to be indicated with two TCI states.
The apparatus of claim 11, wherein the TCI states for the indicated DMRS ports are determined based on CDM group.
The apparatus of claim 1, wherein upon determining that the indicated DMRS ports are from different DMRS port sets, a first TCI state of the two indicated TCI states is used for each of the indicated DMRS ports.
The apparatus of claim 1, wherein upon determining that the indicated DMRS ports are from a same DMRS port set, the TCI states for the indicated DMRS ports are determined based on CDM group.
The apparatus of claim 13, wherein the first TCI state is determined based on a CDM group and/or DMRS port set of a first indicated antenna port.