WO2023050298A1

WO2023050298A1 - Methods and apparatus of qcl determination for epdcch ordered cfra

Info

Publication number: WO2023050298A1
Application number: PCT/CN2021/122139
Authority: WO
Inventors: Yi Zhang; Wei Ling; Chenxi Zhu; Bingchao LIU; Lingling Xiao
Original assignee: Lenovo (Beijing) Limited
Priority date: 2021-09-30
Filing date: 2021-09-30
Publication date: 2023-04-06

Abstract

Methods and apparatus of Quasi Co-Location (QCL) determination for PDCCH scheduling RAR and PDSCH including RAR in the case of enhanced Physical Downlink Control Channel (ePDCCH) ordered Contention Free Random Access (CFRA) are disclosed. The method includes: receiving, by a receiver, a Physical Downlink Control Channel (PDCCH) order, with two Transmission Configuration Indication (TCI) states, for triggering contention free random access; determining, by a processor, a first Quasi Co-Location (QCL) property for a PDCCH scheduling random access response (RAR), and/or a second QCL property for a Physical Downlink Shared Channel (PDSCH) including RAR, based on the two TCI states; and receiving, by the receiver, the PDCCH scheduling RAR based on the first QCL property, and/or the PDSCH including RAR based on the second QCL property.

Description

METHODS AND APPARATUS OF QCL DETERMINATION FOR EPDCCH ORDERED CFRA

FIELD

The subject matter disclosed herein relates generally to wireless communication and more particularly relates to, but not limited to, methods and apparatus of Quasi Co-Location (QCL) determination for PDCCH scheduling RAR and PDSCH including RAR in the case of enhanced Physical Downlink Control Channel (ePDCCH) ordered Contention Free Random Access (CFRA) .

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 Entity/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 Random Access Channel (PRACH) , Physical Broadcast Channel (PBCH) , Enhanced Physical Downlink Control Channel (ePDCCH) , Random Access Channel (RACH) , Control Element (CE) , Control Resource Set (CORESET) , Cyclic redundancy check (CRC) , Channel State Information (CSI) , Channel State Information Reference Signal (CSI-RS) , Common Search Space (CSS) , Downlink Control Information (DCI) , Frequency-Division Multiplexing (FDM) , Frequency Division Multiple Access (FDMA) , Index (ID) , Media Access Control (MAC) , Media Access Control -Control Element (MAC CE) , Primary Cell (PCell) , Physical Resource Block (PRB) , Random Access Response (RAR) , Random Access Radio Network Temporary Identifier (RA-RNTI) , Radio Network Temporary Identifier (RNTI) , Radio Resource Control (RRC) , Reference Signal (RS) , Secondary Cell (SCell) , Single Frequency Network (SFN) , Synchronization Signal Block (SSB) , Time-Division Multiplexing (TDM) , Transmission and Reception Point (TRP) , Frequency Range 1 (FR1) , Frequency Range 2 (FR2) , Synchronization Signal (SS) , Transmission Configuration Indication (TCI) , Technical Specification (TS) , Quasi Co-Location (QCL) , Primary Secondary Cell (PSCell) , Special Cell (SpCell) , Demodulation Reference Signal (DM-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. A TRP may also be referred to as a transmitting-receiving identity, or simply an identity.

In current NR system, Physical Downlink Control Channel (PDCCH) is transmitted from a single TRP. With multiple TRPs, time-frequency resources for PDCCH transmission may be from multiple TRPs. The spatial diversity may be exploited in addition to the time-frequency diversity. Enhanced Physical Downlink Control Channel (ePDCCH) can be transmitted with multiple repetition from multiple TRPs to improve PDCCH transmission reliability and robustness. Multiple transmissions of the ePDCCH may be transmitted from a same TRP or some different TRPs.

Random Access is the procedure where the User Equipment (UE) wants to create an initial connection, or to restore synchronization, with the network. The UE selects a “preamble” (a code sequence) and sends it at a random time on Physical Random Access Channel (PRACH) . The UE starts monitoring the DL channel to see if the base station (gNB) answers the request to connect to the network. CFRA is typically applied when the UE is already in the CONNECTED mode. There are some cases where gNB needs to force UE to initiate the RACH. PDCCH Order is a mechanism by which gNB force UE to initiate a random access procedure, so as to let UE obtain the synchronization with network.

SUMMARY

Methods and apparatus of QCL determination for PDCCH scheduling RAR and PDSCH including RAR in the case of enhanced Physical Downlink Control Channel (PDCCH) ordered CFRA are disclosed.

According to a first aspect, there is provided a method, including: receiving, by a receiver, a Physical Downlink Control Channel (PDCCH) order, with two Transmission Configuration Indication (TCI) states, for triggering contention free random access; determining, by a processor, a first Quasi Co-Location (QCL) property for a PDCCH scheduling random access response (RAR) , and/or a second QCL property for a Physical Downlink Shared Channel (PDSCH) including RAR, based on the two TCI states; and receiving, by the receiver, the PDCCH scheduling RAR based on the first QCL property, and/or the PDSCH including RAR based on the second QCL property.

According to a second aspect, there is provided a method, including: transmitting, by a transmitter, a Physical Downlink Control Channel (PDCCH) order, with two Transmission Configuration Indication (TCI) states, for triggering contention free random access; determining, by a processor, a first Quasi Co-Location (QCL) property for a PDCCH scheduling random access response (RAR) , and/or a second QCL property for a Physical Downlink Shared Channel (PDSCH) including RAR, based on the two TCI states; and transmitting, by the transmitter, the PDCCH scheduling RAR based on the first QCL property, and/or the PDSCH including RAR based on the second QCL property.

According to a third aspect, there is provided an apparatus, including: a receiver that receives a Physical Downlink Control Channel (PDCCH) order, with two Transmission Configuration Indication (TCI) states, for triggering contention free random access; and a processor that determines a first Quasi Co-Location (QCL) property for a PDCCH scheduling random access response (RAR) , and/or a second QCL property for a Physical Downlink Shared Channel (PDSCH) including RAR, based on the two TCI states; wherein the receiver further receives the PDCCH scheduling RAR based on the first QCL property, and/or the PDSCH including RAR based on the second QCL property.

According to a fourth aspect, there is provided an apparatus, including: a transmitter that transmits a Physical Downlink Control Channel (PDCCH) order, with two Transmission Configuration Indication (TCI) states, for triggering contention free random access; and a processor that determines a first Quasi Co-Location (QCL) property for a PDCCH scheduling random access response (RAR) , and/or a second QCL property for a Physical Downlink Shared Channel (PDSCH) including RAR, based on the two TCI states; wherein the transmitter further transmits the PDCCH scheduling RAR based on the first QCL property, and/or the PDSCH including RAR based on the second QCL property.

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;

Figures 4A and 4B are schematic diagrams illustrating examples of a procedure for PDCCH order triggering contention free Physical Random Access Channel (PRACH) in accordance with some implementations of the present disclosure;

Figure 5 is a flow chart illustrating steps of determining QCL for enhanced PDCCH ordered CFRA by UE in accordance with some implementations of the present disclosure; and

Figure 6 is a flow chart illustrating steps of determining QCL for enhanced PDCCH ordered CFRA by gNB or NE 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” 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, 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 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.

The technology disclosed, or at least some of the examples, may be applicable to scenarios with multiple TRPs or without multiple TRPs, as long as multiple PDCCH transmissions are supported.

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.

Figures 4A and 4B are schematic diagrams illustrating examples of a procedure for PDCCH order triggering contention free PRACH in accordance with some implementations of the present disclosure. As shown in Figure 4A, gNB or the base station firstly transmits PDCCH order to trigger contention free PRACH 402. Then, UE transmits PRACH based on PDCCH indication and gNB receives the transmitted PRACH 404. Based on the received PRACH, gNB transmits PDCCH for scheduling random access response (RAR) and Physical Downlink Shared Channel (PDSCH) including RAR 406. In Release 15, Demodulation Reference Signal (DM-RS) for PDSCH including RAR has the same QCL property as DM-RS for PDCCH order. DM-RS for PDCCH scheduling RAR has the same QCL property as DM-RS for PDCCH order in the case of CFRA for SpCell, and has the QCL property of the CORESET associated with the Type1-PDCCH CSS set for receiving PDCCH including DCI format 1_0 in the case of CFRA for Scell. According to the current 3GPP specification, only one beam or one TCI state is used for PDCCH order.

As shown in Figure 4B, the UE 200 is in RRC_Connected state. One of the triggering condition of CFRA is that the UE 200 is out of synchronization. In this example, when there is downlink data arrival at the gNB 300, the gNB will transmit a PDCCH order 402 to initiate the random access procedure. The UE 200, upon receiving the PDCCH order, transmits a PRACH preamble 402 back to the gNB 300. Subsequently, the gNB 300 will send a PRACH Response (RAR) 406 by sending a PDCCH for scheduling the RAR and a PDSCH including the RAR to the UE, in the CFRA procedure.

The QCL determination scheme for PDSCH including RAR is defined in Technical Specification (TS) 38.214, where DM-RS ports of the PDSCH corresponding to the PDCCH order are QCL-ed with DM-RS port of the received PDCCH order. The detailed information is shown as follows.

When receiving a PDSCH scheduled with RA-RNTI in response to a random access procedure triggered by a PDCCH order which triggers contention-free random access procedure for the SpCell [10, TS 38.321] , the UE may assume that the DM-RS port of the received PDCCH order and the DM-RS ports of the corresponding PDSCH scheduled with RA-RNTI are quasi co-located with the same SS/PBCH block or CSI-RS with respect to Doppler shift, Doppler spread, average delay, delay spread, spatial RX parameters when applicable.

The QCL determination scheme for PDCCH scheduling RAR is defined in TS 38.213. DM-RS ports of PDCCH scheduling RAR are QCL-ed with DM-RS port of the corresponding PDCCH order in the case of PDCCH order triggering CFRA for SpCell, and has QCL properties of the CORESET associated with the Type1-PDCCH CSS set for receiving PDCCH including DCI format 1_0 in the case of PDCCH order triggering CFRA for Scell. The detailed information is shown as follows.

If the UE attempts to detect the DCI format 1_0 with CRC scrambled by the corresponding RA-RNTI in response to a PRACH transmission initiated by a PDCCH order that triggers a contention-free random access procedure for the SpCell [11, TS 38.321] , the UE may assume that the PDCCH that includes the DCI format 1_0 and the PDCCH order have same DM-RS antenna port quasi co-location properties.

If the UE attempts to detect the DCI format 1_0 with CRC scrambled by the corresponding RA-RNTI in response to a PRACH transmission initiated by a PDCCH order that triggers a contention-free random access procedure for a secondary cell, the UE may assume the DM-RS antenna port quasi co-location properties of the CORESET associated with the Type1-PDCCH CSS set for receiving the PDCCH that includes the DCI format 1_0.

According to the current 3GPP specification, only one beam or one TCI state is used for PDCCH order. DM-RS for PDSCH transmitting RAR has the same QCL property as DM-RS for PDCCH order. DM-RS for PDCCH scheduling RAR has the same QCL property as DM-RS for PDCCH order in the case of CFRA for SpCell and has the QCL property of the CORESET associated with the Type1-PDCCH CSS set for receiving PDCCH including DCI format 1_0 in the case of CFRA for Scell.

For enhanced PDCCH, two beams or TCI states may be used for TDM/FDM based ePDCCH with repetition and SFN based ePDCCH. That is, ePDCCH order (or PDCCH order transmitted by ePDCCH) may use two TCI states or two beams. PDCCH order transmitted with PDCCH repetitions with different beams triggering CFRA for SpCell may be supported, and determination of the QCL assumption for the PDCCH that includes the DCI format 1_0 with RA-RNTI and the corresponding scheduled PDSCH needs to be specified.

In the disclosure, determination of QCL properties for PDSCH including RAR and for PDCCH scheduling RAR are disclosed when ePDCCH is used for PDCCH order and/or PDCCH scheduling RAR. Different schemes are proposed to determine QCL properties for PDSCH transmitting RAR and PDCCH scheduling RAR. The PDCCH that includes the DCI format 1_0 with RA-RNTI is the same as PDCCH scheduling RAR. The PDSCH scheduled with RA-RNTI is the same as PDSCH including RAR. They are just different description schemes.

QCL determination for PDSCH including RAR

It is assumed that ePDCCH is used for PDCCH order transmission, where TDM/FDM based ePDCCH transmission with repetition or SFN based enhanced PDCCH transmission is used to improve transmission reliability. For TDM/FDM based ePDCCH transmission, two CORESETs with different TCI states can be used for two PDCCH repetition transmissions. For SFN based ePDCCH transmission, two TCI states can be activated for one CORESET. The QCL property for PDSCH including RAR may be derived based on the QCL information of the PDCCH order where two TCI states are used. Two schemes for QCL determination for PDSCH including RAR are proposed.

In the first scheme, only one TCI state is used for PDSCH including RAR. That is, when the PDCCH order with two TCI states is received by UE, the QCL property for PDSCH including RAR is determined by the UE based on a selected TCI state from the two TCI states of the PDCCH order. This is useful especially for UE without capability to support two TCIs for PDSCH transmission. Five options may be used to determine QCL information for PDSCH including RAR under this scheme.

Option 1A: The TCI state from the associated CORESET with a smaller ID is used as the selected TCI state for QCL determination for PDSCH including RAR.

Option 1B: The TCI state of the CORESET associated with the search space set with a smaller ID is used as the selected TCI state for QCL determination for PDSCH including RAR.

Option 1C: DM-RS ports of the PDSCH including RAR are QCL-ed with Synchronization Signal Block (SSB) indicated by the PDCCH order, i.e., the selected TCI state is determined by SSB indicated by the PDCCH order.

Option 1D: The TCI state from a reference PDCCH is used for QCL determination for PDSCH including RAR, and for example, the reference PDCCH is a PDCCH starting later or earlier, or a PDCCH with smaller Physical Resource Block (PRB) index.

Option 1E: The first TCI state of two activated TCI states or the activated TCI state with a lower TCI state ID is used. The term “first TCI state” here may refer to one of the two TCI states activated by MAC CE, which is ordered before another TCI state in the MAC CE.

In some examples, the TCI state used in option 1A, 1B, 1D or 1E may be derived from the PDCCH order. This may be based on a method similar to the current 3GPP specification for Release 15 or Release 16 with single TCI state for PDCCH, where QCL assumption for PDCCH order and PDCCH scheduling RAR are the same.

In some examples, the TCI state used in option 1A, 1B, 1D or 1E may be derived from PDCCH scheduling RAR when two TCI states are used; and the TCI state used for QCL determination for PDCCH scheduling RAR may be used for PDSCH including RAR when only one TCI state is used or selected for QCL determination for PDCCH scheduling RAR.

Options 1A to 1D may be used for PDCCH with repetition for PDCCH order. Options 1C and 1E may be used for SFN based ePDCCH for PDCCH order.

According to the first scheme, the UE assumes the same QCL assumption for one of the TCI states of the PDCCH order and PDSCH including RAR, where the one TCI state may be the TCI state from one of the associated CORESETs with a smaller ID, or the TCI state of a CORESET associated with a linked search space set with a smaller ID, or is determined by SSB indicated by the PDCCH order, or the TCI state from a reference PDCCH, or the first TCI state of two activated TCI states or the activated TCI state with a lower TCI state ID.

In the second scheme, two TCI states are used for PDSCH including RAR. It is useful especially for high speed train scenario, where two activated TCI states can be used for SFN based PDCCH and PDSCH transmission. The QCL property for PDSCH including RAR is determined based on the two TCI states of the PDCCH order. The UE assumes PDSCH including RAR has the same two TCIs as those for the PDCCH order.

In an example, the first TCI state of the PDCCH order is used for determining the first TCI state of the PDSCH including RAR; and the second TCI state of the PDCCH order is used for determining the second TCI state of the PDSCH including RAR. The QCL property for PDSCH including RAR includes the QCL property of an initial PDSCH transmission corresponding to the first TCI state for an initial transmission of the PDCCH order; and the QCL property of a repetition PDSCH transmission corresponding to the second TCI state for a repetition transmission of the PDCCH order.

In one example, when SFN based ePDCCH is used for PDCCH order, the RRC parameter “sfnSchemePdcch” may be used to configure SFN scheme for PDCCH, which includes scheme 1 (sfnSchemeA) or TRP-based pre-compensation (sfnSchemeB) . This RRC parameter may also implicitly enable two TCI states for PDSCH including RAR. Otherwise, Release 15 behaviour may be used, where a single TCI state is used for PDCCH order and this TCI state is also used for QCL determination for PDSCH including RAR.

In another example, the RRC parameter “sfnSchemePdsch” may be used to enable SFN based PDSCH. When “sfnSchemePdcch” is enabled for PDCCH order, SFN based PDSCH transmission is used only when the RRC parameter “sfnSchemePdsch” is also enabled, and not used when the RRC parameter “sfnSchemePdsch” is not enabled.

If only one search space set is configured to monitor the PDCCH order, Release 15 behaviour is used, where a single TCI state of PDCCH order is used for PDSCH transmission including RAR. When two linked search space sets are configured for monitoring PDCCH order transmitted by TDM/FDM based enhanced PDCCH, the two schemes mentioned above are used for determining QCL property for PDSCH including RAR. In certain scenarios, the first scheme may be used. In certain scenarios, RRC parameter may be used to switch between the first scheme and the second scheme since the second scheme requires higher UE capability for supporting PDSCH transmission with two TCI states. For example, the RRC parameter “enableTwoDefaultTCIStates” may be reused here. When “enableTwoDefaultTCIStates” is enabled, two TCI states from the PDCCH order are used for PDSCH including RAR. When “enableTwoDefaultTCIStates” is not enabled, one specific TCI state of the two TCT states from the PDCCH order is used for PDSCH including RAR.

According to the second scheme, the RRC parameter “sfnSchemePdcch” may be used to implicitly indicate whether one or two TCI states are used for determining the QCL property for PDSCH including RAR. The RRC parameters “sfnSchemePdcch” and “sfnSchemePdsch” may be used together to determine whether one or two TCI states are used for determining the QCL property for PDSCH including RAR. The RRC parameter “enableTwoDefaultTCIStates” may be used to indicate implicitly whether one selected TCI state or two TCI states are used for PDSCH including RAR. If available RRC signaling cannot be reused, new RRC signaling may be introduced to indicate whether one or two TCI states are used for determining the QCL property for PDSCH including RAR.

QCL determination for PDCCH scheduling RAR

Similar to QCL determination schemes defined in the specification, QCL assumption for PDCCH scheduling RAR, where ePDCCH is used for PDCCH order transmission, may be based on the following two cases. Case 1: PRACH transmission initiated by a PDCCH order that triggers a contention-free random access procedure for a SpCell; Case 2: PRACH transmission initiated by a PDCCH order that triggers a contention-free random access procedure for a secondary cell.

For case 1 where PRACH transmission is initiated by a PDCCH order that triggers a contention-free random access procedure for a SpCell, three schemes are proposed to determine QCL for PDCCH scheduling RAR.

In a first scheme, the QCL property for PDCCH scheduling RAR is determined to be the same as that of the PDCCH order, where the PDCCH order is transmitted on Pcell.

That is, two TCI states may be used for PDCCH scheduling RAR. This requires that enhanced PDCCH with two TCI states can be used for PDCCH transmission from Type-1 CSS, i.e. PDCCH scheduling RAR.

The first scheme applies to scenarios where SFN based ePDCCH is used for both PDCCH order and PDCCH scheduling RAR. The UE has to be able to support receiving ePDCCH for PDCCH scheduling RAR. When PDCCH with repetition is used for both PDCCH order and PDCCH scheduling RAR, the first TCI state corresponding to the first transmission of the PDCCH order has the same QCL property as the first TCI state corresponding to the first transmission of PDCCH scheduling RAR; and the second TCI state corresponding to the second (i.e., repetition) transmission of the PDCCH order has the same QCL property as the second TCI state corresponding to the second (i.e., repetition) transmission of PDCCH scheduling RAR. In this scheme, the same number of TCI states is used for PDCCH order and PDCCH scheduling RAR.

In a second scheme, the QCL property for PDCCH scheduling RAR is determined based on an indicated TCI state of a CORESET associated with PDCCH scheduling RAR. For example, it is determined based on the QCL of the CORESET associated with Type1-PDCCH CSS set for PDCCH scheduling RAR.

In the third scheme, the QCL property for PDCCH scheduling RAR is determined based on a selected TCI state from the two TCI states of the PDCCH order.

Under this scheme, five options may be used to determine QCL information for PDCCH scheduling RAR.

Option 2A: The TCI state from the associated CORESET with a smaller ID is used for QCL determination for PDCCH scheduling RAR.

Option 2B: The TCI state of the CORESET associated with the search space set with a smaller ID is used for QCL determination for PDCCH scheduling RAR.

Option 2C: DM-RS ports of PDCCH scheduling RAR are QCL-ed with SSB indicated by the PDCCH order, i.e., the selected TCI state is determined by SSB indicated by the PDCCH order.

Option 2D: The TCI state from a reference PDCCH is used for QCL determination for PDCCH scheduling RAR, and for example, the reference PDCCH is a PDCCH starting later or earlier, or a PDCCH with smaller PRB index.

Option 2E: The first TCI state of two activated TCI state or the activated TCI state with a lower TCI state ID is used. The term “first TCI state” here may refer to one of the two TCI states activated by MAC CE, which is ordered before another TCI state in the MAC CE.

These five options are similar to those of the first scheme for determining QCL for PDSCH including RAR. The first 4 options, i.e. options 2A to 2D may be used in the scenarios of PDCCH repetition transmission for PDCCH order. Options 2C and 2E may be used in the scenarios of SFN based ePDCCH transmission for PDCCH order.

For case 2 where PRACH transmission is initiated by a PDCCH order that triggers a contention-free random access procedure for a secondary cell, one scheme, which is a natural extension based on Release 15 scheme defined in the current specification, may be used. In the scheme, if only one TCI state is used for QCL of the CORESET associated with Type1-PDCCH CSS set, Release 15 behaviour is assumed; and if two TCI states are activated for QCL of the CORESET associated with Type1-PDCCH CSS set, two TCI states may be used for determining QCL for PDCCH scheduling RAR.

For case 2, it is also possible that the QCL property for PDCCH scheduling RAR is determined based on an indicated TCI state of corresponding CORESET. For example, it is determined based on QCL of the CORESET associated with Type1-PDCCH CSS set for PDCCH scheduling RAR.

Figure 5 is a flow chart illustrating steps of determining QCL for enhanced PDCCH ordered CFRA by UE 200 in accordance with some implementations of the present disclosure.

At step 502, the receiver 214 of UE 200 receives a Physical Downlink Control Channel (PDCCH) order, with two Transmission Configuration Indication (TCI) states, for triggering contention free random access.

At step 504, the processor 202 of UE 200 determines a first Quasi Co-Location (QCL) property for a PDCCH scheduling random access response (RAR) , and/or a second QCL property for a Physical Downlink Shared Channel (PDSCH) including RAR, based on the two TCI states.

At step 506, the receiver 214 of UE 200 receives the PDCCH scheduling RAR based on the first QCL property, and/or the PDSCH including RAR based on the second QCL property.

Figure 6 is a flow chart illustrating steps of determining QCL for enhanced PDCCH ordered CFRA by gNB or NE 300 in accordance with some implementations of the present disclosure.

At step 602, the transmitter 312 of NE 300 transmits a Physical Downlink Control Channel (PDCCH) order, with two Transmission Configuration Indication (TCI) states, for triggering contention free random access.

At step 604, the processor 302 of NE 300 determines a first Quasi Co-Location (QCL) property for a PDCCH scheduling random access response (RAR) , and/or a second QCL property for a Physical Downlink Shared Channel (PDSCH) including RAR, based on the two TCI states.

At step 606, the transmitter 312 of NE 300 transmits the PDCCH scheduling RAR based on the first QCL property, and/or the PDSCH including RAR based on the second QCL property.

In one aspect, some items as examples of the disclosure concerning a method of a UE or remote device may be summarized as follows:

1. A method, comprising:

receiving, by a receiver, a Physical Downlink Control Channel (PDCCH) order, with two Transmission Configuration Indication (TCI) states, for triggering contention free random access;

determining, by a processor, a first Quasi Co-Location (QCL) property for a PDCCH scheduling random access response (RAR) , and/or a second QCL property for a Physical Downlink Shared Channel (PDSCH) including RAR, based on the two TCI states; and

receiving, by the receiver, the PDCCH scheduling RAR based on the first QCL property, and/or the PDSCH including RAR based on the second QCL property.

2. The method of item 1, wherein the PDCCH order with two TCI states is received from repetition transmission from two Control Resource Sets (CORESETs) or Single Frequency Network (SFN) transmission from one CORESET.

3. The method of item 1, wherein the second QCL property for PDSCH including RAR is determined based on a selected TCI state from the two TCI states of the PDCCH order.

4. The method of item 3, wherein two TCI states are linked with two associated CORESETs for transmission of the PDCCH order with repetition; and the selected TCI state is a TCI state from one of the associated CORESETs with a smaller index (ID) .

5. The method of item 3, wherein the selected TCI state is a TCI state of a CORESET associated with a linked search space set with a smaller ID.

6. The method of item 3, wherein the selected TCI state is determined by Synchronization Signal Block (SSB) indicated by the PDCCH order.

7. The method of item 3, wherein the selected TCI state is a TCI state from a reference PDCCH; and the reference PDCCH is a PDCCH starting later or earlier, or a PDCCH with smaller Physical Resource Block (PRB) index.

8. The method of item 3, wherein the selected TCI state is a first TCI state of two activated TCI states or a TCI state with a lower TCI state ID.

9. The method of item 1, wherein the second QCL property for PDSCH including RAR is determined based on the two TCI states of the PDCCH order.

10. The method of item 9, wherein a first TCI state of the PDCCH order is used for determining a first TCI state of the PDSCH including RAR; and a second TCI state of the PDCCH order is used for determining a second TCI state of the PDSCH including RAR.

11. The method of item 9, wherein the second QCL property comprises QCL property of an initial PDSCH transmission corresponding to a first TCI state for an initial transmission of the PDCCH order; and QCL property of a repetition PDSCH transmission corresponding to a second TCI state for a repetition transmission of the PDCCH order.

12. The method of item 3 or 9, wherein using whether one or two TCI states for determining the second QCL property is indicated implicitly by RRC signaling “sfnSchemePdcch” and/or “enableTwoDefaultTCIStates” .

13. The method of item 3 or 9, wherein using whether one or two TCI states for determining the second QCL property is indicated implicitly by RRC signaling “sfnSchemePdcch” and/or “sfnSchemePdsch” .

14. The method of item 1, wherein the first QCL property for PDCCH scheduling RAR is determined to be the same as that of the PDCCH order.

15. The method of item 1, wherein the first QCL property for PDCCH scheduling RAR is determined based on an indicated TCI state of a CORESET associated with PDCCH scheduling RAR.

16. The method of item 1, wherein the first QCL property for PDCCH scheduling RAR is determined based on a selected TCI state from the two TCI states of the PDCCH order.

17. The method of any one of items 14 to 16, wherein the first QCL property for PDCCH scheduling RAR is determined for contention free random access on Special Cell (SpCell) triggered by PDCCH order.

18. The method of any one of items 14 to 16, wherein the first QCL property for PDCCH scheduling RAR is determined for contention free random access on Secondary Cell (SCell) triggered by PDCCH order.

19. The method of item 16, wherein the selected TCI state is any one of: a TCI state from an associated CORESET with a smaller ID where two TCI states are linked with two associated CORESETs for transmission of the PDCCH order with repetition; a TCI state of a CORESET associated with a linked search space set with a smaller ID; a TCI state determined by Synchronization Signal Block (SSB) indicated by the PDCCH order; a TCI state from a reference PDCCH as PDCCH starting later or earlier, or a PDCCH with smaller Physical Resource Block (PRB) index; and a first TCI state of two activated TCI states or a TCI state with lower TCI state ID.

In another aspect, some items as examples of the disclosure concerning a method of a NE or gNB may be summarized as follows:

20. A method, comprising:

transmitting, by a transmitter, a Physical Downlink Control Channel (PDCCH) order, with two Transmission Configuration Indication (TCI) states, for triggering contention free random access;

transmitting, by the transmitter, the PDCCH scheduling RAR based on the first QCL property, and/or the PDSCH including RAR based on the second QCL property.

21. The method of item 20, wherein the PDCCH order with two TCI states is received from repetition transmission from two Control Resource Sets (CORESETs) or Single Frequency Network (SFN) transmission from one CORESET.

22. The method of item 20, wherein the second QCL property for PDSCH including RAR is determined based on a selected TCI state from the two TCI states of the PDCCH order.

23. The method of item 22, wherein two TCI states are linked with two associated CORESETs for transmission of the PDCCH order with repetition; and the selected TCI state is a TCI state from one of the associated CORESETs with a smaller index (ID) .

24. The method of item 22, wherein the selected TCI state is a TCI state of a CORESET associated with a linked search space set with a smaller ID.

25. The method of item 22, wherein the selected TCI state is determined by Synchronization Signal Block (SSB) indicated by the PDCCH order.

26. The method of item 22, wherein the selected TCI state is a TCI state from a reference PDCCH; and the reference PDCCH is a PDCCH starting later or earlier, or a PDCCH with smaller Physical Resource Block (PRB) index.

27. The method of item 22, wherein the selected TCI state is a first TCI state of two activated TCI states or a TCI state with a lower TCI state ID.

28. The method of item 20, wherein the second QCL property for PDSCH including RAR is determined based on the two TCI states of the PDCCH order.

29. The method of item 28, wherein a first TCI state of the PDCCH order is used for determining a first TCI state of the PDSCH including RAR; and a second TCI state of the PDCCH order is used for determining a second TCI state of the PDSCH including RAR.

30. The method of item 28, wherein the second QCL property comprises QCL property of an initial PDSCH transmission corresponding to a first TCI state for an initial transmission of the PDCCH order; and QCL property of a repetition PDSCH transmission corresponding to a second TCI state for a repetition transmission of the PDCCH order.

31. The method of item 22 or 28, wherein using whether one or two TCI states for determining the second QCL property is indicated implicitly by RRC signaling “sfnSchemePdcch” and/or “enableTwoDefaultTCIStates” .

32. The method of item 22 or 28, wherein using whether one or two TCI states for determining the second QCL property is indicated implicitly by RRC signaling “sfnSchemePdcch” and/or “sfnSchemePdsch” .

33. The method of item 20, wherein the first QCL property for PDCCH scheduling RAR is determined to be the same as that of the PDCCH order.

34. The method of item 20, wherein the first QCL property for PDCCH scheduling RAR is determined based on an indicated TCI state of a CORESET associated with PDCCH scheduling RAR.

35. The method of item 20, wherein the first QCL property for PDCCH scheduling RAR is determined based on a selected TCI state from the two TCI states of the PDCCH order.

36. The method of any one of items 33 to 35, wherein the first QCL property for PDCCH scheduling RAR is determined for contention free random access on Special Cell (SpCell) triggered by PDCCH order.

37. The method of any one of items 33 to 35, wherein the first QCL property for PDCCH scheduling RAR is determined for contention free random access on Secondary Cell (SCell) triggered by PDCCH order.

38. The method of item 35, wherein the selected TCI state is any one of: a TCI state from an associated CORESET with a smaller ID where two TCI states are linked with two associated CORESETs for transmission of the PDCCH order with repetition; a TCI state of a CORESET associated with a linked search space set with a smaller ID; a TCI state determined by Synchronization Signal Block (SSB) indicated by the PDCCH order; a TCI state from a reference PDCCH as PDCCH starting later or earlier, or a PDCCH with smaller Physical Resource Block (PRB) index; and a first TCI state of two activated TCI states or a TCI state with lower TCI state ID.

In a further aspect, some items as examples of the disclosure concerning a UE or remote device may be summarized as follows:

39. An apparatus, comprising:

a receiver that receives a Physical Downlink Control Channel (PDCCH) order, with two Transmission Configuration Indication (TCI) states, for triggering contention free random access; and

a processor that determines a first Quasi Co-Location (QCL) property for a PDCCH scheduling random access response (RAR) , and/or a second QCL property for a Physical Downlink Shared Channel (PDSCH) including RAR, based on the two TCI states;

wherein the receiver further receives the PDCCH scheduling RAR based on the first QCL property, and/or the PDSCH including RAR based on the second QCL property.

40. The apparatus of item 39, wherein the PDCCH order with two TCI states is received from repetition transmission from two Control Resource Sets (CORESETs) or Single Frequency Network (SFN) transmission from one CORESET.

41. The apparatus of item 39, wherein the second QCL property for PDSCH including RAR is determined based on a selected TCI state from the two TCI states of the PDCCH order.

42. The apparatus of item 41, wherein two TCI states are linked with two associated CORESETs for transmission of the PDCCH order with repetition; and the selected TCI state is a TCI state from one of the associated CORESETs with a smaller index (ID) .

43. The apparatus of item 41, wherein the selected TCI state is a TCI state of a CORESET associated with a linked search space set with a smaller ID.

44. The apparatus of item 41, wherein the selected TCI state is determined by Synchronization Signal Block (SSB) indicated by the PDCCH order.

45. The apparatus of item 41, wherein the selected TCI state is a TCI state from a reference PDCCH; and the reference PDCCH is a PDCCH starting later or earlier, or a PDCCH with smaller Physical Resource Block (PRB) index.

46. The apparatus of item 41, wherein the selected TCI state is a first TCI state of two activated TCI states or a TCI state with a lower TCI state ID.

47. The apparatus of item 39, wherein the second QCL property for PDSCH including RAR is determined based on the two TCI states of the PDCCH order.

48. The apparatus of item 47, wherein a first TCI state of the PDCCH order is used for determining a first TCI state of the PDSCH including RAR; and a second TCI state of the PDCCH order is used for determining a second TCI state of the PDSCH including RAR.

49. The apparatus of item 47, wherein the second QCL property comprises QCL property of an initial PDSCH transmission corresponding to a first TCI state for an initial transmission of the PDCCH order; and QCL property of a repetition PDSCH transmission corresponding to a second TCI state for a repetition transmission of the PDCCH order.

50. The apparatus of item 41 or 47, wherein using whether one or two TCI states for determining the second QCL property is indicated implicitly by RRC signaling “sfnSchemePdcch” and/or “enableTwoDefaultTCIStates” .

51. The apparatus of item 41 or 47, wherein using whether one or two TCI states for determining the second QCL property is indicated implicitly by RRC signaling “sfnSchemePdcch” and/or “sfnSchemePdsch” .

52. The apparatus of item 39, wherein the first QCL property for PDCCH scheduling RAR is determined to be the same as that of the PDCCH order.

53. The apparatus of item 39, wherein the first QCL property for PDCCH scheduling RAR is determined based on an indicated TCI state of a CORESET associated with PDCCH scheduling RAR.

54. The apparatus of item 39, wherein the first QCL property for PDCCH scheduling RAR is determined based on a selected TCI state from the two TCI states of the PDCCH order.

55. The apparatus of any one of items 52 to 54, wherein the first QCL property for PDCCH scheduling RAR is determined for contention free random access on Special Cell (SpCell) triggered by PDCCH order.

56. The apparatus of any one of items 52 to 54, wherein the first QCL property for PDCCH scheduling RAR is determined for contention free random access on Secondary Cell (SCell) triggered by PDCCH order.

57. The apparatus of item 54, wherein the selected TCI state is any one of: a TCI state from an associated CORESET with a smaller ID where two TCI states are linked with two associated CORESETs for transmission of the PDCCH order with repetition; a TCI state of a CORESET associated with a linked search space set with a smaller ID; a TCI state determined by Synchronization Signal Block (SSB) indicated by the PDCCH order; a TCI state from a reference PDCCH as PDCCH starting later or earlier, or a PDCCH with smaller Physical Resource Block (PRB) index; and a first TCI state of two activated TCI states or a TCI state with lower TCI state ID.

In a yet further aspect, some items as examples of the disclosure concerning a NE or gNB may be summarized as follows:

58. An apparatus, comprising:

a transmitter that transmits a Physical Downlink Control Channel (PDCCH) order, with two Transmission Configuration Indication (TCI) states, for triggering contention free random access; and

wherein the transmitter further transmits the PDCCH scheduling RAR based on the first QCL property, and/or the PDSCH including RAR based on the second QCL property.

59. The apparatus of item 58, wherein the PDCCH order with two TCI states is received from repetition transmission from two Control Resource Sets (CORESETs) or Single Frequency Network (SFN) transmission from one CORESET.

60. The apparatus of item 58, wherein the second QCL property for PDSCH including RAR is determined based on a selected TCI state from the two TCI states of the PDCCH order.

61. The apparatus of item 60, wherein two TCI states are linked with two associated CORESETs for transmission of the PDCCH order with repetition; and the selected TCI state is a TCI state from one of the associated CORESETs with a smaller index (ID) .

62. The apparatus of item 60, wherein the selected TCI state is a TCI state of a CORESET associated with a linked search space set with a smaller ID.

63. The apparatus of item 60, wherein the selected TCI state is determined by Synchronization Signal Block (SSB) indicated by the PDCCH order.

64. The apparatus of item 60, wherein the selected TCI state is a TCI state from a reference PDCCH; and the reference PDCCH is a PDCCH starting later or earlier, or a PDCCH with smaller Physical Resource Block (PRB) index.

65. The apparatus of item 60, wherein the selected TCI state is a first TCI state of two activated TCI states or a TCI state with a lower TCI state ID.

66. The apparatus of item 58, wherein the second QCL property for PDSCH including RAR is determined based on the two TCI states of the PDCCH order.

67. The apparatus of item 66, wherein a first TCI state of the PDCCH order is used for determining a first TCI state of the PDSCH including RAR; and a second TCI state of the PDCCH order is used for determining a second TCI state of the PDSCH including RAR.

68. The apparatus of item 66, wherein the second QCL property comprises QCL property of an initial PDSCH transmission corresponding to a first TCI state for an initial transmission of the PDCCH order; and QCL property of a repetition PDSCH transmission corresponding to a second TCI state for a repetition transmission of the PDCCH order.

69. The apparatus of item 60 or 66, wherein using whether one or two TCI states for determining the second QCL property is indicated implicitly by RRC signaling “sfnSchemePdcch” and/or “enableTwoDefaultTCIStates” .

70. The apparatus of item 60 or 66, wherein using whether one or two TCI states for determining the second QCL property is indicated implicitly by RRC signaling “sfnSchemePdcch” and/or “sfnSchemePdsch” .

71. The apparatus of item 58, wherein the first QCL property for PDCCH scheduling RAR is determined to be the same as that of the PDCCH order.

72. The apparatus of item 58, wherein the first QCL property for PDCCH scheduling RAR is determined based on an indicated TCI state of a CORESET associated with PDCCH scheduling RAR.

73. The apparatus of item 58, wherein the first QCL property for PDCCH scheduling RAR is determined based on a selected TCI state from the two TCI states of the PDCCH order.

74. The apparatus of any one of items 71 to 73, wherein the first QCL property for PDCCH scheduling RAR is determined for contention free random access on Special Cell (SpCell) triggered by PDCCH order.

75. The apparatus of any one of items 71 to 73, wherein the first QCL property for PDCCH scheduling RAR is determined for contention free random access on Secondary Cell (SCell) triggered by PDCCH order.

76. The apparatus of item 73, wherein the selected TCI state is any one of: a TCI state from an associated CORESET with a smaller ID where two TCI states are linked with two associated CORESETs for transmission of the PDCCH order with repetition; a TCI state of a CORESET associated with a linked search space set with a smaller ID; a TCI state determined by Synchronization Signal Block (SSB) indicated by the PDCCH order; a TCI state from a reference PDCCH as PDCCH starting later or earlier, or a PDCCH with smaller Physical Resource Block (PRB) index; and a first TCI state of two activated TCI states or a TCI state with lower TCI state ID.

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

A method, comprising:

receiving, by a receiver, a Physical Downlink Control Channel (PDCCH) order, with two Transmission Configuration Indication (TCI) states, for triggering contention free random access;

determining, by a processor, a first Quasi Co-Location (QCL) property for a PDCCH scheduling random access response (RAR) , and/or a second QCL property for a Physical Downlink Shared Channel (PDSCH) including RAR, based on the two TCI states; and

receiving, by the receiver, the PDCCH scheduling RAR based on the first QCL property, and/or the PDSCH including RAR based on the second QCL property.
The method of claim 1, wherein the PDCCH order with two TCI states is received from repetition transmission from two Control Resource Sets (CORESETs) or Single Frequency Network (SFN) transmission from one CORESET.
The method of claim 1, wherein the second QCL property for PDSCH including RAR is determined based on a selected TCI state from the two TCI states of the PDCCH order.
The method of claim 3, wherein two TCI states are linked with two associated CORESETs for transmission of the PDCCH order with repetition; and the selected TCI state is a TCI state from one of the associated CORESETs with a smaller index (ID) .
The method of claim 3, wherein the selected TCI state is a TCI state of a CORESET associated with a linked search space set with a smaller ID.
The method of claim 3, wherein the selected TCI state is determined by Synchronization Signal Block (SSB) indicated by the PDCCH order.
The method of claim 3, wherein the selected TCI state is a TCI state from a reference PDCCH; and the reference PDCCH is a PDCCH starting later or earlier, or a PDCCH with smaller Physical Resource Block (PRB) index.
The method of claim 3, wherein the selected TCI state is a first TCI state of two activated TCI states or a TCI state with a lower TCI state ID.
The method of claim 1, wherein the second QCL property for PDSCH including RAR is determined based on the two TCI states of the PDCCH order.
The method of claim 3, wherein using whether one or two TCI states for determining the second QCL property is indicated implicitly by RRC signaling “sfnSchemePdcch” , “enableTwoDefaultTCIStates” , and/or “sfnSchemePdsch” .
The method of claim 1, wherein the first QCL property for PDCCH scheduling RAR is determined to be the same as that of the PDCCH order.
The method of claim 1, wherein the first QCL property for PDCCH scheduling RAR is determined based on an indicated TCI state of a CORESET associated with PDCCH scheduling RAR.
The method of claim 1, wherein the first QCL property for PDCCH scheduling RAR is determined based on a selected TCI state from the two TCI states of the PDCCH order.
The method of any one of claims 11 to 13, wherein the first QCL property for PDCCH scheduling RAR is determined for contention free random access on Special Cell (SpCell) triggered by PDCCH order, or on Secondary Cell (SCell) triggered by PDCCH order.
The method of claim 13, wherein the selected TCI state is any one of: a TCI state from an associated CORESET with a smaller ID where two TCI states are linked with two associated CORESETs for transmission of the PDCCH order with repetition; a TCI state of a CORESET associated with a linked search space set with a smaller ID; a TCI state determined by Synchronization Signal Block (SSB) indicated by the PDCCH order; a TCI state from a reference PDCCH as PDCCH starting later or earlier, or a PDCCH with smaller Physical Resource Block (PRB) index; and a first TCI state of two activated TCI states or a TCI state with lower TCI state ID.