PDCCH reliability enhancement

Abstract

Systems and methods for PDCCH reliability are disclosed. PDCCH can be improved by introducing multi-TRP, multi-beam or repeated PDCCH transmission and reception. In some methods and systems, PDCCH is transmitted on multiple CORESETs (control resource sets), each CORESET is associated with a TCI state. In some cases, it is beneficial if the UE can determine that multiple received DCIs are repeated so as not to repeat the corresponding UE actions. Methods and systems for DCI repetition determination are disclosed. In some methods and systems, PDCCH is transmitted in a single CORESET, where the CORESET is associated with multiple TCI states. Various ways of applying different TCI states to different non-overlapping frequency portions of a CORESET or to the entire CORESET are proposed. In addition, in some cases, the TCI state used for PDCCH can also be used for subsequent PDSCH reception. The present disclosure also presents methods and systems on how to apply multiple TCI states of a received PDCCH to subsequent PDSCH reception.

Description

[0001] Citation of Related Applications

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 976,095, filed on February 13, 2020, entitled “RELIABILITY ENHANCEMENT FOR PDCCH,” the contents of which are hereby incorporated by reference herein. Background Art

[0003] A challenge for ultra-reliable low-latency wireless communications is the sudden deterioration of radio conditions that may occur due to UE mobility and dynamic environments. For example, the channel between the UE and the serving TRP (transmit or receive point) may suddenly be blocked, such as by a building or a truck. This phenomenon is particularly evident in the mmWave spectrum. Such sudden deep fades of the radio channel may prohibit ultra-reliable low-latency communications.

[0004] In most cellular communication systems, the downlink control channel, such as PDCCH (Physical Downlink Control Channel) in 3GPP NR, is of great significance for maintaining the link because it can be used for purposes such as selecting a beam or TRP for subsequent DL or UL data transmission, adapting the modulation and coding scheme of data transmission, scheduling retransmission of data transmission, and quickly increasing the UL transmit power. Subsequent data transmissions, such as NR PDSCH or PUSCH (Physical Downlink Shared Channel or Physical Uplink Shared Channel), are also important because they can be used to report beam failure or reconfigure the link, but they usually rely on the downlink control channel for initial scheduling as well as retransmission. Therefore, improving the reliability of downlink control channels (such as NR PDCCH) is of great significance to ensure ultra-reliable low-latency communication links, especially in mmWave spectrum. Summary of the invention

[0005] Disclosed are systems and methods that can improve the reliability of a physical downlink control channel (PDCCH) in a communication network. A process for providing a PDCCH can include sending a PDCCH transmission to a user device via multiple transmission mediums. The multiple transmission mediums can be at least one of transmissions from multiple transmit / receive points (TRPs), multi-beam transmissions, and repeated transmissions of PDCCH transmissions. The PDCCH can be sent on multiple control resource sets (CORESETs), wherein each of the multiple CORESETs is associated with a transmission control indicator (TCI) state. The PDCCH can also be sent on a single control resource set (CORESET), and the single CORESET is associated with multiple transmission control indicator (TCI) states.

[0006] This summary is provided to introduce some concepts in a simplified form, which will be further described in the detailed description below. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. In addition, the claimed subject matter is not limited to limitations that solve any or all deficiencies mentioned in any part of this disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1A An example communication system is illustrated in which the methods and apparatus described and claimed herein may be implemented.

[0008] Figure 1B Illustrated is a block diagram of an example device or apparatus configured for wireless communications.

[0009] Figure 1C A system diagram illustrating an example radio access network (RAN) and core network.

[0010] Figure 1D A system diagram illustrating another example RAN and core network.

[0011] Figure 1E is another example system diagram of the RAN and core network.

[0012] Figure 1F A block diagram illustrating an example computing system is shown.

[0013] Figure 1G A block diagram of another example communication system is illustrated.

[0014] Figure 2 The diagram illustrates seven PDCCH resources (PR1-PR7) in a BWP during four slots based on three combinations of CORESETs (C1 and C2) and associated search space sets (S1, S2, and S3).

[0015] Figure 3 The diagram illustrates the process performed by a UE to handle a set of inconsistent DCIs.

[0016] Figure 4 The diagram illustrates TDMed PDCCH resources, including a first PDCCH resource associated with CORESET X1, search space set Y1, and activated TCI state Z1, and a second PDCCH resource associated with CORESET X2, search space set Y2, and activated TCI state Z2.

[0017] Figure 5 Illustration of FDMed PDCCH resources.

[0018] Fig. 6AThe diagram illustrates the process performed by the UE to determine DCI repetition.

[0019] Figure 6B The diagram illustrates the process performed by the UE to determine DCI repetition.

[0020] Figure 7 The diagram illustrates the process performed by the UE to determine PDCCH candidates for soft combining.

[0021] Figure 8 The diagram illustrates the process performed by a UE to receive or decode PDCCH candidates in a duplication set.

[0022] Fig. 9 The diagram illustrates the case where, for the special case where the PDCCH, PDSCH and PUCCH are in the same BWP (eg, also in the same carrier), two PDCCHs indicate the same PDSCH but different PUCCH resources.

[0023] Fig.10 The diagram illustrates the allocation of two TCI states (Z0 and Z1) per REG bundle for various CORESET configurations.

[0024] Fig.11 The diagram illustrates the assignment of two TCI states to a CORESET containing two groups of consecutive RBs.

[0025] Fig.12 Illustrate an example indication of two TCI state IDs for a UE-specific PDCCH MAC CE.

[0026] Fig.13 The diagram illustrates reference PDCCH resources for determining the case of QCL assumptions for subsequent scheduled PDSCHs.

[0027] Fig.14 Illustrated is a reference PDCCH resource used to indicate the case of preempted DL resources.

[0028] Fig.15 The diagram illustrates example processes performed by a UE to determine one or more reference resources. DETAILED DESCRIPTION

[0029] The Third Generation Partnership Project (3GPP) develops technical standards for cellular telecommunication network technologies, including radio access, core transport networks, and service capabilities - including work on codecs, security, and quality of service. Recent radio access technology (RAT) standards include WCDMA (commonly referred to as 3G), LTE (commonly referred to as 4G), and LTE-Advanced standards. 3GPP has begun work on the standardization of the next generation cellular technology called New Radio (NR) (also referred to as "5G"). 3GPP NR standard development is expected to include the definition of the next generation radio access technology (new RAT), which is expected to include the provision of new flexible radio access below 6 GHz, and the provision of new ultra-mobile broadband radio access above 6 GHz. Flexible radio access is expected to consist of new non-backward compatible radio access in new spectrum below 6 GHz, and is expected to include different operating modes that can be reused together in the same spectrum to address a wide range of 3GPP NR use cases with different requirements. Ultra-mobile broadband is expected to include cmWave and mmWave spectrum, which will provide opportunities for ultra-mobile broadband access for indoor applications and hotspots, for example. In particular, ultra-mobile broadband is expected to share a common design framework with sub-6 GHz flexible radio access, with cmWave and mmWave specific design optimizations.

[0030] 3GPP has identified a variety of use cases that NR is expected to support, resulting in a variety of user experience requirements for data rates, latency, and mobility. Use cases include the following general categories: enhanced mobile broadband (e.g., broadband access in dense areas, ultra-high broadband access indoors, broadband access in crowds, 50+Mbps everywhere, ultra-low-cost broadband access, mobile broadband in vehicles), emergency communications, massive machine-type communications, network operations (e.g., network slicing, routing, migration and interworking, energy saving), and enhanced vehicle-to-everything (eV2X) communications, which may include any of vehicle-to-vehicle communications (V2V), vehicle-to-infrastructure communications (V2I), vehicle-to-network communications (V2N), vehicle-to-pedestrian communications (V2P), and communications between vehicles and other entities. Specific services and applications in these categories include, for example, surveillance and sensor networks, device remote control, two-way remote control, personal cloud computing, video streaming, wireless cloud office, first responder connectivity, car emergency calls, disaster alerts, real-time gaming, multi-person video calls, autonomous driving, augmented reality, tactile Internet, and virtual reality, to name a few. All of these and other use cases are envisioned in this article.

[0031] Figure 1A An embodiment of an example communication system 100 is illustrated in which the communication devices described and claimed herein, such as in Figure 2-Figure 15 In and with Figure 2-Figure 15 Associated methods and devices. As shown, the example communication system 100 may include wireless transmit / receive units (WTRUs) 102a, 102b, 102c, 102d, 102e, 102f, or 102g (which may be generally or collectively referred to as WTRUs 102), radio access networks (RANs) 103 / 104 / 105 / 103b / 104b / 105b, core networks 106 / 107 / 109, public switched telephone networks (PSTNs) 108, the Internet 110, other networks 112, and V2X servers (or ProSe functions and servers) 113, but it is to be appreciated that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, or network elements. Each of the WTRUs 102a, 102b, 102c, 102d, 102e, 102f, 102g may be any type of device or apparatus configured to operate or communicate in a wireless environment. Although each WTRU 102a, 102b, 102c, 102d, 102e, 102f, 102g is Figure 1A-1E , but it should be understood that for the various use cases envisioned for 5G wireless communications, each WTRU may include or be implemented in any type of device or apparatus configured to send or receive wireless signals, including, by way of example only, a user equipment (UE), a mobile station, a fixed or mobile subscriber unit, a pager, a cellular telephone, a personal digital assistant (PDA), a smart phone, a laptop, a tablet, a netbook, a notebook computer, a personal computer, a wireless sensor, a consumer electronic product, a wearable device such as a smart watch or smart clothing, a medical or e-health device, a robot, an industrial equipment, a drone, a vehicle such as a car, truck, train or airplane, and the like.

[0032] The communication system 100 may also include a base station 114a and a base station 114b. The base station 114a may be any type of device configured to wirelessly interface with at least one of the WTRUs 102a, 102b, 102c to facilitate access to one or more communication networks, such as the core network 106 / 107 / 109, the Internet 110, or other networks 112. The base station 114b may be any type of device configured to wired or wirelessly interface with at least one of the RRHs (remote radio heads) 118a, 118b, TRPs (transmit and receive points) 119a, 119b, or RSUs (roadside units) 120a and 120b to facilitate access to one or more communication networks, such as the core network 106 / 107 / 109, the Internet 110, other networks 112, or a V2X server (or ProSe function and server) 113. The RRHs 118a, 118b may be any type of device configured to wirelessly interface with at least one of the WTRUs 102c to facilitate access to one or more communication networks, such as the core network 106 / 107 / 109, the Internet 110, or other networks 112. The TRPs 119a, 119b may be any type of device configured to wirelessly interface with at least one of the WTRUs 102d to facilitate access to one or more communication networks, such as the core network 106 / 107 / 109, the Internet 110, or other networks 112. The RSUs 120a and 120b may be any type of device configured to wirelessly interface with at least one of the WTRUs 102e or 102f to facilitate access to one or more communication networks, such as the core network 106 / 107 / 109, the Internet 110, other networks 112, or a V2X server (or ProSe function and server) 113. For example, the base stations 114a, 114b may be a base transceiver station (BTS), a Node-B, an eNode B, a Home Node B, a Home eNodeB, a site controller, an access point (AP), a wireless router, etc. Although the base stations 114a, 114b are depicted as a single element, it will be appreciated that the base stations 114a, 114b may include any number of interconnected base stations or network elements.

[0033] The base station 114a may be part of the RAN 103 / 104 / 105, which may also include other base stations or network elements (not shown), such as a base station controller (BSC), a radio network controller (RNC), a relay node, etc. The base station 114b may be part of the RAN 103b / 104b / 105b, which may also include other base stations or network elements (not shown), such as a base station controller (BSC), a radio network controller (RNC), a relay node, etc. The base station 114a may be configured to send or receive wireless signals in a specific geographic area, which may be referred to as a cell (not shown). The base station 114b may be configured to send or receive wired or wireless signals in a specific geographic area, which may be referred to as a cell (not shown). The cell may be further divided into cell sectors. For example, the cell associated with the base station 114a may be divided into three sectors. Thus, in an embodiment, the base station 114a may include three transceivers, for example, one transceiver for each sector of the cell. In an embodiment, the base station 114a may employ multiple-input multiple-output (MIMO) technology and, thus, may utilize multiple transceivers for each sector of the cell.

[0034] The base station 114a may communicate with one or more of the WTRUs 102a, 102b, 102c over an air interface 115 / 116 / 117, which may be any suitable wireless communication link (e.g., radio frequency (RF), microwave, infrared (IR), ultraviolet (UV), visible light, cmWave, mmWave, etc.). The air interface 115 / 116 / 117 may be established using any suitable radio access technology (RAT). The base station 114b may communicate with one or more of the RRHs 118a, 118b, TRPs 119a, 119b, or RSUs 120a and 120b via a wired or air interface 115b / 116b / 117b, which may be any suitable wired (e.g., cable, fiber optic, etc.) or wireless communication link (e.g., radio frequency (RF), microwave, infrared (IR), ultraviolet (UV), visible light, cmWave, mmWave, etc.). The air interface 115b / 116b / 117b may be established using any suitable radio access technology (RAT).

[0035] The RRH 118a, 118b, TRP 119a, 119b or RSU 120a, 120b may communicate with one or more of the WTRUs 102c, 102d, 102e, 102f via an air interface 115c / 116c / 117c, which may be any suitable wireless communication link (e.g., radio frequency (RF), microwave, infrared (IR), ultraviolet (UV), visible light, cmWave, mmWave, etc.). The air interface 115c / 116c / 117c may be established using any suitable radio access technology (RAT).

[0036] The WTRUs 102a, 102b, 102c, 102d, 102e, 102f, or 102g may communicate with each other via an air interface 115d / 116d / 117d (not shown), which may be any suitable wireless communication link (e.g., radio frequency (RF), microwave, infrared (IR), ultraviolet (UV), visible light, cmWave, mmWave, etc.). The air interface 115d / 116d / 117d may be established using any suitable radio access technology (RAT).

[0037] More specifically, as described above, the communication system 100 may be a multiple access system and may employ one or more channel access schemes, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, etc. For example, the base station 114a in the RAN 103 / 104 / 105 and the WTRUs 102a, 102b, 102c, or the RRHs 118a, 118b, TRPs 119a, 119b and RSUs 120a, 120b and the WTRUs 102c, 102d, 102e, 102f in the RAN 103b / 104b / 105b may implement a radio technology such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which may use Wideband CDMA (WCDMA) to establish the air interface 115 / 116 / 117 or 115c / 116c / 117c, respectively. WCDMA may include communication protocols such as High Speed ​​Packet Access (HSPA) or Evolved HSPA (HSPA+). HSPA may include High Speed ​​Downlink Packet Access (HSDPA) or High Speed ​​Uplink Packet Access (HSUPA).

[0038] In an embodiment, the base station 114a and the WTRU 102a, 102b, 102c, or the RRH 118a, 118b, TRP 119a, 119b or RSU 120a, 120b and the WTRU 102c, 102d in the RAN 103b / 104b / 105b may implement a radio technology such as Evolved UMTS Terrestrial Radio Access (E-UTRA), which may use Long Term Evolution (LTE) or LTE-Advanced (LTE-A) to establish an air interface 115 / 116 / 117 or 115c / 116c / 117c, respectively. In the future, the air interface 115 / 116 / 117 may implement 3GPP NR technology. LTE and LTE-A technologies include LTE D2D and V2X technologies and interfaces (such as sidelink communications, etc.). 3GPP NR technology includes NR V2X technologies and interfaces (such as sidelink communications, etc.).

[0039] In an embodiment, the base station 114a in the RAN 103 / 104 / 105 and the WTRUs 102a, 102b, 102c, or the RRH 118a, 118b, RP 119a, 119b or RSU 120a, 120b and the WTRUs 102c, 102d, 102e, 102f in the RAN 103b / 104b / 105b may implement a radio technology such as IEEE 802.16 (e.g., Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 IX, CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System for Mobile communications (GSM), Enhanced Data rates for GSM Evolution (EDGE), GSM EDGE (GERAN), etc.

[0040] Figure 1A The base station 114c in the example may be, for example, a wireless router, a Home Node B, a Home eNode B, or an access point, and may utilize any suitable RAT to facilitate wireless connectivity in a local area (such as a business location, a home, a vehicle, a campus, etc.). In an embodiment, the base station 114c and the WTRU 102e may implement a radio technology such as IEEE 802.11 to establish a wireless local area network (WLAN). In an embodiment, the base station 114c and the WTRU 102d may implement a radio technology such as IEEE 802.15 to establish a wireless personal area network (WPAN). In another embodiment, the base station 114c and the WTRU 102e may utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, etc.) to establish a pico cell or a femto cell. Figure 1A As shown in FIG, base station 114b may have a direct connection to the Internet 110. Thus, base station 114c may not be required to access the Internet 110 via core network 106 / 107 / 109.

[0041] The RAN 103 / 104 / 105 or the RAN 103b / 104b / 105b may be in communication with a core network 106 / 107 / 109, which may be any type of network configured to provide voice, data, applications, or Voice over Internet Protocol (VoIP) services to one or more of the WTRUs 102a, 102b, 102c, 102d. For example, the core network 106 / 107 / 109 may provide call control, billing services, mobile location-based services, pre-paid calling, Internet connectivity, video distribution, etc., or perform high-level security functions, such as user authentication.

[0042] Although not in Figure 1A 105b or RAN 103b / 104b / 105b or the core network 106 / 107 / 109 may be in direct or indirect communication with other RANs that employ the same RAT as the RAN 103 / 104 / 105 or RAN 103b / 104b / 105b or a different RAT. For example, in addition to being connected to the RAN 103 / 104 / 105 or RAN 103b / 104b / 105b, which may utilize E-UTRA radio technology, the core network 106 / 107 / 109 may also be in communication with another RAN (not shown) that employs GSM radio technology.

[0043] The core network 106 / 107 / 109 may also serve as a gateway for the WTRUs 102a, 102b, 102c, 102d, 102e to access the PSTN 108, the Internet 110, or other networks 112. The PSTN 108 may include a circuit-switched telephone network that provides plain old telephone service (POTS). The Internet 110 may include a global system of interconnected computer networks and devices that use common communication protocols, such as the Transmission Control Protocol (TCP), the User Datagram Protocol (UDP), and the Internet Protocol (IP) in the TCP / IP Internet protocol suite. The networks 112 may include wired or wireless communication networks owned or operated by other service providers. For example, the networks 112 may include another core network connected to one or more RANs, which may use the same RAT as the RAN 103 / 104 / 105 or the RAN 103b / 104b / 105b or a different RAT.

[0044] Some or all of the WTRUs 102a, 102b, 102c, 102d in the communication system 100 may include multi-mode capabilities, e.g., the WTRUs 102a, 102b, 102c, 102d, and 102e may include multiple transceivers for communicating with different wireless networks via different wireless links. Figure 1A The WTRU 102e shown in FIG. 1 may be configured to communicate with the base station 114a, which may employ a cellular-based radio technology, and with the base station 114c, which may employ an IEEE 802 radio technology.

[0045] Figure 1B is an example device or apparatus configured for wireless communication according to the embodiments illustrated herein, such as the WTRU 102 (e.g., with Figure 2-Figure 15 A block diagram of a UE) is shown in FIG. Figure 1B As shown in , the example WTRU 102 may include a processor 118, a transceiver 120, a transmit / receive element 122, a speaker / microphone 124, a keypad 126, a display / touchpad / indicator 128, a non-removable memory 130, a removable memory 132, a power supply 134, a global positioning system (GPS) chipset 136, and other peripherals 138. It is to be appreciated that the WTRU 102 may include any sub-combination of the above elements while still being consistent with the embodiment. In addition, the embodiment contemplates that the base stations 114a and 114b, or the nodes that the base stations 114a and 114b may represent, such as but not limited to a transceiver station (BTS), a Node-B, a site controller, an access point (AP), a home node-B, an evolved home node-B (eNodeB), a home evolved node-B (HeNB), a home evolved node-B gateway, and a proxy node, etc. may be included in Figure 1B Some or all of the elements depicted in and described herein.

[0046] The processor 118 may be a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors associated with a DSP core, a controller, a microcontroller, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) circuit, any other type of integrated circuit (IC), a state machine, etc. The processor 118 may perform signal coding, data processing, power control, input / output processing, or any other functionality that enables the WTRU 102 to operate in a wireless environment. The processor 118 may be coupled to the transceiver 120, which may be coupled to the transmit / receive element 122. Although Figure 1BThe processor 118 and the transceiver 120 are depicted as separate components, although it is appreciated that the processor 118 and the transceiver 120 may be integrated together in an electronic package or chip.

[0047] The send / receive element 122 may be configured to send or receive signals to and from a base station (e.g., base station 114a) via an air interface 115 / 116 / 117. For example, in an embodiment, the send / receive element 122 may be an antenna configured to send or receive an RF signal. In an embodiment, the send / receive element 122 may be a transmitter / detector configured to send or receive, for example, an IR, UV, or visible light signal. In another embodiment, the send / receive element 122 may be configured to send and receive both an RF signal and an optical signal. It is to be appreciated that the send / receive element 122 may be configured to send or receive any combination of wireless signals.

[0048] In addition, although the transmit / receive element 122 is Figure 1B Although depicted as a single element in the diagram, the WTRU 102 may include any number of transmit / receive elements 122. More specifically, the WTRU 102 may employ MIMO technology. Thus, in an embodiment, the WTRU 102 may include two or more transmit / receive elements 122 (e.g., multiple antennas) for transmitting and receiving wireless signals over the air interface 115 / 116 / 117.

[0049] The transceiver 120 may be configured to modulate signals to be transmitted by the transmit / receive element 122, and to demodulate signals received by the transmit / receive element 122. As described above, the WTRU 102 may have multi-mode capabilities. Thus, the transceiver 120 may include multiple transceivers for enabling the WTRU 102 to communicate via multiple RATs, such as UTRA and IEEE 802.11.

[0050] The processor 118 of the WTRU 102 may be coupled to a speaker / microphone 124, a keypad 126, or a display / touchpad / indicator 128 (e.g., a liquid crystal display (LCD) display unit or an organic light emitting diode (OLED) display unit), and may receive user input data therefrom. The processor 118 may also output user data to the speaker / microphone 124, the keypad 126, or the display / touchpad / indicator 128. In addition, the processor 118 may access information from and store data in any type of suitable memory, such as a non-removable memory 130 or a removable memory 132. The non-removable memory 130 may include a random access memory (RAM), a read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory 132 may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, etc. In an embodiment, the processor 118 may access information from and store data in a memory that is not physically located on the WTRU 102, such as a memory on a server or a home computer (not shown).

[0051] The processor 118 may receive power from the power source 134 and may be configured to distribute power to, or control power to, the other components in the WTRU 102. The power source 134 may be any suitable device for providing power to the WTRU 102. For example, the power source 134 may include one or more dry cell batteries, solar cells, fuel cells, etc.

[0052] The processor 118 may also be coupled to the GPS chipset 136, which may be configured to provide location information (e.g., longitude and latitude) regarding the current location of the WTRU 102. The WTRU 102 may receive location information from a base station (e.g., base stations 114a, 114b) over the air interface 115 / 116 / 117 in addition to or in lieu of the information from the GPS chipset 136, or determine its location based on the timing of receiving signals from two or more nearby base stations. It will be appreciated that the WTRU 102 may acquire location information by any suitable location-determination method while remaining consistent with an embodiment.

[0053] The processor 118 may also be coupled to other peripherals 138, which may include one or more software or hardware modules that provide additional features, functionality, or wired or wireless connectivity. For example, the peripherals 138 may include various sensors such as accelerometers, biometric (e.g., fingerprint) sensors, electronic compasses, satellite transceivers, digital cameras (for photos or videos), universal serial bus (USB) ports or other interconnect interfaces, vibration devices, television transceivers, hands-free headsets, modules, FM radio units, digital music players, media players, video game player modules, internet browsers, etc.

[0054] The WTRU 102 may be implemented in other devices or apparatuses, such as sensors, consumer electronics, wearable devices such as smart watches or smart clothing, medical or e-health devices, robots, industrial equipment, drones, vehicles such as cars, trucks, trains, or airplanes. The WTRU 102 may be connected to other components, modules, or systems of such devices or apparatuses via one or more interconnect interfaces, such as an interconnect interface that may include one of the peripheral devices 138.

[0055] Figure 1C According to the embodiment, for example Figure 2-Figure 15 and Figure 2-Figure 15 102a, 102b, and 102c over the air interface 115. The RAN 103 may also be in communication with the core network 106. Figure 1C As shown in FIG. 1 , the RAN 103 may include Node-Bs 140a, 140b, 140c, each of which may include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 115. The Node-Bs 140a, 140b, 140c may each be associated with a particular cell (not shown) within the RAN 103. The RAN 103 may also include RNCs 142a, 142b. It will be appreciated that the RAN 103 may include any number of Node-Bs and RNCs while still being consistent with an embodiment.

[0056] like Figure 1CAs shown in , Node-B 140a, 140b can communicate with RNC 142a. In addition, Node-B 140c can communicate with RNC 142b. Node-B 140a, 140b, 140c can communicate with corresponding RNC 142a, 142b via Iub interface. RNC 142a, 142b can communicate with each other via Iur interface. Each of RNC 142a, 142b can be configured to control the corresponding Node-B 140a, 140b, 140c to which it is connected. In addition, each of RNC 142a, 142b can be configured to perform or support other functions, such as outer loop power control, load control, admission control, packet scheduling, handover control, macro diversity, security functions, data encryption, etc.

[0057] Figure 1C The core network 106 shown in FIG. 1 may include a media gateway (MGW) 144, a mobile switching center (MSC) 146, a serving GPRS support node (SGSN) 148, or a gateway GPRS support node (GGSN) 150. Although each of the above elements is depicted as part of the core network 106, it is appreciated that any of these elements may be owned or operated by an entity other than the core network operator.

[0058] The RNC 142a in the RAN 103 may be connected to the MSC 146 in the core network 106 via an IuCS interface. The MSC 146 may be connected to the MGW 144. The MSC 146 and the MGW 144 may provide the WTRUs 102a, 102b, 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, 102c and traditional land-line communications devices.

[0059] The RNC 142a in the RAN 103 may also be connected to the SGSN 148 in the core network 106 via an IuPS interface. The SGSN 148 may be connected to the GGSN 150. The SGSN 148 and the GGSN 150 may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices.

[0060] As described above, core network 106 may also be connected to networks 112, which may include other wired or wireless networks owned or operated by other service providers.

[0061] Figure 1D According to the embodiment, for example Figure 2-Figure 15and Figure 2-Figure 15 A system diagram of the associated RAN 104 and core network 107. As noted above, the RAN 104 may employ an E-UTRA radio technology to communicate with the WTRUs 102a, 102b, and 102c over the air interface 116. The RAN 104 may also be in communication with the core network 107.

[0062] The RAN 104 may include eNode-Bs 160a, 160b, 160c, though it will be appreciated that the RAN 104 may include any number of eNode-Bs while remaining consistent with an embodiment. The eNode-Bs 160a, 160b, 160c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In an embodiment, the eNode-Bs 160a, 160b, 160c may implement MIMO technology. Thus, for example, the eNode-B 160a may use multiple antennas to send and receive wireless signals to and from the WTRU 102a.

[0063] Each of the eNode-Bs 160a, 160b, and 160c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in uplink or downlink, etc. Figure 1D As shown in FIG. , eNode-Bs 160a, 160b, 160c may communicate with each other via an X2 interface.

[0064] Figure 1D The core network 107 shown in FIG. 1 may include a mobility management gateway (MME) 162, a serving gateway 164, and a packet data network (PDN) gateway 166. Although each of the above elements is depicted as part of the core network 107, it is appreciated that any of these elements may be owned or operated by an entity other than the core network operator.

[0065] The MME 162 may be connected to each of the eNode-Bs 160a, 160b, and 160c in the RAN 104 via an S1 interface and may serve as a control node. For example, the MME 162 may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, bearer activation / deactivation, selecting a particular serving gateway during an initial attach of the WTRUs 102a, 102b, 102c, and the like. The MME 162 may also provide a control plane function for switching between the RAN 104 and other RANs (not shown) that employ other radio technologies, such as GSM or WCDMA.

[0066] The serving gateway 164 may be connected to each of the eNode-Bs 160a, 160b, and 160c in the RAN 104 via an S1 interface. The serving gateway 164 may generally route and forward user data packets to and from the WTRUs 102a, 102b, 102c. The serving gateway 164 may also perform other functions, such as anchoring the user plane during inter-eNode B handovers, triggering paging when downlink data is available for the WTRUs 102a, 102b, 102c, managing and storing the contexts of the WTRUs 102a, 102b, 102c, and the like.

[0067] The serving gateway 164 may also be connected to the PDN gateway 166, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices.

[0068] The core network 107 may facilitate communications with other networks. For example, the core network 107 may provide the WTRUs 102a, 102b, 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, 102c and traditional land-line communications devices. For example, the core network 107 may include, or may be in communication with, an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that acts as an interface between the core network 107 and the PSTN 108. In addition, the core network 107 may provide the WTRUs 102a, 102b, 102c with access to the networks 112, which may include other wired or wireless networks owned or operated by other service providers.

[0069] Figure 1E According to the embodiment, for example Figure 2-Figure 15 and Figure 2-Figure 15 System diagram of the associated RAN 105 and core network 109. The RAN 105 may be an access service network (ASN) that employs IEEE 802.16 radio technology to communicate with the WTRUs 102a, 102b, and 102c over the air interface 117. As further described below, the communication links between the different functional entities of the WTRUs 102a, 102b, 102c, the RAN 105, and the core network 109 may be defined as reference points.

[0070] like Figure 1EAs shown in , the RAN 105 may include base stations 180a, 180b, 180c and an ASN gateway 182, although it should be appreciated that the RAN 105 may include any number of base stations and ASN gateways while still being consistent with the embodiment. The base stations 180a, 180b, 180c may each be associated with a particular cell in the RAN 105 and may include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 117. In an embodiment, the base stations 180a, 180b, 180c may implement MIMO technology. Thus, for example, the base station 180a may use multiple antennas to send wireless signals to and receive wireless signals from the WTRU 102a. The base stations 180a, 180b, 180c may also provide mobility management functions, such as handover triggering, tunnel establishment, radio resource management, traffic classification, quality of service (QoS) policy enforcement, and the like. The ASN gateway 182 may act as a traffic aggregation point and may be responsible for paging, caching of subscriber profiles, routing to the core network 109, and the like.

[0071] The air interface 117 between the WTRUs 102a, 102b, 102c and the RAN 105 may be defined as an R1 reference point that implements the IEEE 802.16 specification. In addition, each of the WTRUs 102a, 102b, and 102c may establish a logical interface (not shown) with the core network 109. The logical interface between the WTRUs 102a, 102b, 102c and the core network 109 may be defined as an R2 reference point, which may be used for authentication, authorization, IP host configuration management, or mobility management.

[0072] The communication link between each of the base stations 180a, 180b, and 180c may be defined as an R8 reference point, which includes protocols that facilitate WTRU handovers and the transfer of data between base stations. The communication link between the base stations 180a, 180b, 180c and the ASN gateway 182 may be defined as an R6 reference point. The R6 reference point may include protocols that facilitate mobility management based on mobility events associated with each of the WTRUs 102a, 102b, 102c.

[0073] like Figure 1EAs shown in , the RAN 105 may be connected to a core network 109. The communication link between the RAN 105 and the core network 109 may be defined as an R3 reference point, which includes, for example, protocols that facilitate data transfer and mobility management capabilities. The core network 109 may include a mobile IP home agent (MIP-HA) 184, an authentication, authorization, accounting (AAA) server 186, and a gateway 188. Although each of the above elements is depicted as part of the core network 109, it will be appreciated that any of these elements may be owned or operated by an entity other than the core network operator.

[0074] The MIP-HA may be responsible for IP address management and may enable the WTRUs 102a, 102b, and 102c to roam between different ASNs or different core networks. The MIP-HA 184 may provide the WTRUs 102a, 102b, and 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, and 102c and IP-enabled devices. The AAA server 186 may be responsible for user authentication and supporting user services. The gateway 188 may facilitate interworking with other networks. For example, the gateway 188 may provide the WTRUs 102a, 102b, and 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, and 102c and traditional land-line communication devices. In addition, the gateway 188 may provide the WTRUs 102a, 102b, 102c with access to the networks 112, which may include other wired or wireless networks owned or operated by other service providers.

[0075] Although not in Figure 1E 105 may be connected to other ASNs and the core network 109 may be connected to other core networks. The communication link between the RAN 105 and the other ASNs may be defined as an R4 reference point, which may include protocols for coordinating the mobility of the WTRUs 102a, 102b, 102c between the RAN 105 and the other ASNs. The communication link between the core network 109 and the other core networks may be defined as an R5 reference point, which may include protocols for facilitating interworking between the home core network and the visited core network.

[0076] Described in this article and Figure 1A , Figure 1C , Figure 1D and Figure 1EThe core network entities illustrated in the diagram are identified using names given to these entities in certain existing 3GPP specifications, but it should be understood that in the future, these entities and functions may be identified by other names, and in future specifications published by 3GPP, including future 3GPP NR specifications, some entities or functions may be merged. Figure 1A-1E The specific network entities and functions described and illustrated in the present disclosure are provided by way of example only, and it should be understood that the subject matter disclosed and claimed herein may be embodied or implemented in any similar communication system, whether currently defined or defined in the future.

[0077] Figure 1F is a block diagram of an example computing system 90 in which Figure 1A , Figure 1C , Figure 1D and Figure 1E One or more devices of the communication network illustrated in the diagram, such as in Figure 2-Figure 15 and Figure 2-Figure 15 The computing system 90 may include a computer or a server and may be primarily controlled by computer-readable instructions, which may be in the form of software, regardless of where or how such software is stored or accessed. Such computer-readable instructions may be executed in the processor 91 to enable the computing system 90 to work. The processor 91 may be a general-purpose processor, a special-purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors associated with a DSP core, a controller, a microcontroller, an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) circuit, any other type of integrated circuit (IC), a state machine, etc. The processor 91 may perform signal encoding, data processing, power control, input / output processing, or any other function that enables the computing system 90 to operate in a communication network. The coprocessor 81 is an optional processor that is different from the main processor 91 and can perform additional functions or assist the processor 91. Processor 91 or coprocessor 81 may receive, generate and process data related to the methods and apparatus disclosed herein.

[0078] In operation, processor 91 retrieves, decodes and executes instructions, and transfers information to and from other resources via the computer system's main data transfer path, system bus 80. Such a system bus connects components in computing system 90 and defines the medium for data exchange. System bus 80 generally includes data lines for sending data, address lines for sending addresses, and control lines for sending interrupts and for operating the bus. An example of such a system bus 80 is a PCI (Peripheral Component Interconnect) bus.

[0079] The memory coupled to the system bus 80 includes a random access memory (RAM) 82 and a read-only memory (ROM) 93. Such a memory includes circuits that allow information to be stored and retrieved. ROM 93 generally contains stored data that cannot be easily modified. The data stored in RAM 82 can be read or changed by the processor 91 or other hardware devices. Access to RAM 82 or ROM 93 can be controlled by a memory controller 92. The memory controller 92 can provide an address translation function that converts a virtual address into a physical address when an instruction is executed. The memory controller 92 can also provide a memory protection function that isolates processes within the system and isolates system processes from user processes. Thus, a program running in the first mode can only access memory mapped by its own process virtual address space; unless memory sharing between processes is set, it cannot access memory in the virtual address space of other processes.

[0080] In addition, the computing system 90 may include a peripheral device controller 83 , which is responsible for transmitting instructions from the processor 91 to peripheral devices, such as a printer 94 , a keyboard 84 , a mouse 95 , and a disk drive 85 .

[0081] The display 86 controlled by the display controller 96 is used to display the visual output generated by the computing system 90. Such visual output may include text, graphics, animated graphics, and video. The visual output may be provided in the form of a graphical user interface (GUI). The display 86 may be implemented using a CRT-based video display, an LCD-based flat panel display, a gas plasma-based flat panel display, or a touch panel. The display controller 96 includes the electronic components required to generate the video signal sent to the display 86.

[0082] In addition, the computing system 90 may include a communication network that can be used to connect the computing system 90 to an external communication network, such as Figure 1A-1EThe RAN 103 / 104 / 105, core network 106 / 107 / 109, PSTN 108, Internet 110 or other network 112 of the present invention may be used to enable the computing system 90 to communicate with other nodes or functional entities of these networks through communication circuits, such as a network adapter 97. Alone or in combination with the processor 91, the communication circuits may be used to perform the sending and receiving steps of certain devices, nodes or functional entities described herein.

[0083] Figure 1G An embodiment of an example communication system 111 is illustrated in which the methods described and claimed herein may be implemented, such as in Figure 2-Figure 15 and Figure 2-Figure 15 Associated methods and apparatus. As shown, an example communication system 111 may include wireless transmit / receive (WTRU) A, B, C, D, E, F, a base station, a V2X server, and RSUs A and B, although it will be appreciated that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, or network elements. One or several or all of the WTRUs A, B, C, D, E may be outside the range of the network (e.g., outside the cell coverage boundary represented as a dashed line in the figure). WTRUs A, B, C form a V2X group, where WTRU A is the group leader and WTRUs B and C are group members. WTRUs A, B, C, D, E, F may communicate via a Uu interface or a sidelink (PC5) interface.

[0084] It should be understood that any or all of the devices, systems, methods, and processes described herein may be implemented in the form of computer executable instructions (e.g., program code) stored on a computer-readable storage medium, which, when executed by a processor, such as processor 118 or 91, causes the processor to perform or implement the systems, methods, and processes described herein. Specifically, any step, operation, or function described herein may be implemented in the form of such computer executable instructions executed on a processor of a device or computing system configured for wireless network communication or wired network communication. Computer-readable storage media include volatile and non-volatile, removable and non-removable media implemented in any non-temporary (e.g., tangible or physical) method or technology for storage of information, but such computer-readable storage media do not include signals. Computer-readable storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disk (DVD) or other optical disk storage, cassette, tape, magnetic disk storage or other magnetic storage, or any other tangible or physical medium that can be used to store the desired information and can be accessed by a computing system.

[0085] Control Resource Set (CORESET)

[0086] A bandwidth part (BWP) can be configured with one or more CORESETs. CORESET configuration involves many aspects of PDCCH reception.

[0087] A CORESET may be configured with one or more of the following parameters: a CORESET identity (e.g., controlResourceSetld), frequency domain resources, duration, a control channel element (CCE) to resource element group (REG) bundle mapping type (e.g., cce-REG-MappingType), a configuration associated with an interleaved CCE to REG bundle mapping type, a precoder granularity, a list of TCI state IDs, an indication of whether the TCI field is present or absent in a DL-related DCI (e.g., tci-PresentInDCI), a PDCCH DMRS scrambling sequence initialization ID (e.g., pdcch-DMRS-ScramblingID), or a CORESET pool index, and the like.

[0088] With reference to frequency domain resources (e.g., frequencyDomainResources), a bitmap may be configured where one bit represents a group of resource blocks (RBs), e.g., 6 RBs. The first bit may correspond to the first RB group in a BWP, etc. A bit set to 1 indicates that the RB group belongs to the frequency domain resources of the CORESET.

[0089] Duration: The duration can be configured in the form of a number of symbols (OFDM symbols), where the symbol duration is based on the subcarrier spacing used in the BWP. The duration can be 1, 2 or 3 symbols.

[0090] The control channel element (CCE) to resource element group (REG) bundle mapping type (e.g., cce-REG-MappingType) can be interleaved or non-interleaved. If the CCE to REG bundle mapping type is interleaved, the following can be configured: 1) REG bundle size (e.g., reg-BundleSize), which can be 2, 3, or 6 REGs; 2) interleaver size (e.g., interleaverSize), which can be 2, 3, or 6; or 3) REG shift index (e.g., shiftIndex).

[0091] Precoder granularity (e.g., precoderGranularity), which defines on which REGs the UE may assume that the transmitter uses the same transmission scheme, e.g., precoding. One granularity may correspond to a REG bundle (e.g., sameAsREG-bundle), for example, the UE may assume that the same transmission scheme (e.g., precoder) is used within a REG bundle. In this case, the UE shall assume that the PDCCH DMRS is only mapped to the REGs that constitute the PDCCH that the UE is attempting to decode. One granularity may correspond to one or more groups of contiguous RBs (e.g., allContiguousRBs). In this case, the UE shall assume that the PDCCH DMRS is mapped to all REGs within the group of contiguous RBs in the CORESET where the UE is attempting to decode the PDCCH.

[0092] A list of TCI state IDs (eg, configured by tci-StatesPDCCH-ToAddList and tci-StatesPDCCH-ToReleaseList). The actual TCI state and the corresponding ID may be configured in the IE PDSCH-Config.

[0093] CORESET pool index (e.g., CORESETPoolIndex): A binary index can be used to divide the CORESET into two pools. The two values ​​can correspond to different TRPs. The PDCCH from the first TRP can be sent using the CORESET of the first pool. The PDCCH from the second TRP can be sent using the CORESET of the second pool. The UE can be configured to feedback HARQ-ACK for one or more PDSCHs scheduled from the first pool and for one or more PDSCHs scheduled from the second pool, respectively. This allows the TRPs to operate more independently, for example in terms of scheduling. This may be necessary in scenarios where the backhaul between TRPs is not ideal, for example where the communication latency is on the order of milliseconds or tens of milliseconds.

[0094] Search Space Set

[0095] In some cases, a search space set is referred to as a search space. For example, in some cases "search space set" is used, while in other cases "search space" is used. These terms will be used interchangeably herein.

[0096] A BWP may be configured with one or more search space sets.Search space set configuration involves many aspects of PDCCH reception.

[0097] The search space set can be configured with at least the following parameters: a search space set identifier (e.g., searchSpaceId); an association between the search space set and the CORESET, such as by configuring the CORESET identifier (e.g., controlResourceSetId); a PDCCH monitoring periodicity and a monitoring offset (with reference to certain system frame numbers) (e.g., monitoringSlotPeriodicityAndOffset); a PDCCH monitoring pattern within a timeslot, indicating the first symbol of the CORESET within a timeslot (e.g., monitoringSymbolsWithinSlot); a duration, such as the number of timeslots in which the search space set exists (e.g., duration); the number of PDCCH candidates for each control channel element (CCE) aggregation level; an indication of whether the type of the search space set is common (CSS) or UE-specific (USS) (e.g., searchSpaceType); or a DCI format that the UE will monitor in the search space set, etc.

[0098] Each control channel element (CCE) aggregation level can have multiple PDCCH candidates. For example, it can be configured by the parameter nrofCandidates. The parameter is a sequence of : 1) aggregationLevel1: the number of PDCCH candidates of CCE aggregation level 1; or 2) aggregationLevel2: the number of PDCCH candidates of CCE aggregation level 2; and so on.

[0099] Problem Statement

[0100] The configured search space set and the associated CORESET define how the UE should receive the PDCCH. Note that there are other configurations that have potential impact on PDCCH monitoring, such as transmitted SSB, slot format, DRX, power saving, etc.

[0101] A challenge for ultra-reliable low-latency wireless communications is the sudden deterioration of radio conditions that may occur due to UE mobility and dynamic environments. For example, the channel between the UE and the serving TRP (transmit or receive point) may suddenly be blocked, such as by a building or a truck. This phenomenon is particularly evident in the mmWave spectrum. Such sudden deep fades of the radio channel may prohibit ultra-reliable and low-latency communications.

[0102] In most cellular communication systems, the downlink control channel, such as PDCCH (Physical Downlink Control Channel) in 3GPP NR, is of great significance for maintaining the link because it can be used for purposes such as selecting a beam or TRP for subsequent DL or UL data transmission, adapting the modulation and coding scheme of data transmission, scheduling retransmission of data transmission, or quickly increasing the UL transmit power. Subsequent data transmissions, such as NR PDSCH or PUSCH (Physical Downlink Shared Channel or Physical Uplink Shared Channel), are also important because they can be used to report beam failure or reconfigure the link, but they usually rely on the downlink control channel for initial scheduling as well as retransmission. Therefore, improving the reliability of downlink control channels (such as NR PDCCH) is of great significance to ensure ultra-reliable low-latency communication links, especially in mmWave spectrum.

[0103] One way to address the challenge of sudden radio link blocking is to introduce diversity, for example in the form of multi-TRP communication. In a multi-TRP communication link, the UE is served simultaneously by multiple TRPs that are usually geographically separated. If the radio channel to one TRP is suddenly blocked, the communication link can still work normally by using the remaining serving TRPs.

[0104] PDCCH reliability can be achieved by introducing multiple TRPs, multiple beams, or repeated PDCCH transmission and reception. A TRP or beam can correspond to a transmission configuration indicator (TCI) state.

[0105] In some methods, the PDCCH is sent on multiple CORESETs (Control Resource Sets), where each CORESET is associated with a TCI state.

[0106] In some cases, it may be beneficial if the UE can determine that multiple received DCIs are duplicates so as not to repeat the corresponding UE actions.Disclosed herein are various methods that may address DCI duplication determination.

[0107] In some cases, it is beneficial if the UE can determine a small set of PDCCH candidates through which the network will send repeated DCI or no DCI. With this a priori knowledge, the UE can avoid unnecessary repeated actions and in some cases even perform DCI soft combining with limited additional complexity.

[0108] In some methods, PDCCH is transmitted in a single CORESET, where the CORESET is associated with multiple TCI states. Various ways of applying different TCI states to different disjoint frequency portions of a CORESET or to the entire CORESET are proposed.

[0109] In addition, in some cases, the TCI state used for the PDCCH may also be used for subsequent PDSCH reception. The present disclosure also introduces a method on how to apply multiple TCI states of a received PDCCH to subsequent PDSCH reception.

[0110] PDCCH resources

[0111] In various cases, the time-frequency resources used to receive a set of PDCCH candidates may be defined by a combination of a CORESET and a search space set. The CORESET configuration may define aspects related to frequency domain resources, duration, beam / precoder assumptions, DMRS sequences, etc. The search space set configuration may define aspects related to where in time the time-frequency resources used to receive a set of PDCCH candidates are, such as in which time slots and in which symbols in a time slot.

[0112] For simplicity, the time-frequency resources used to receive a set of PDCCH candidates are referred to herein as "PDCCH resources". A PDCCH resource is an occasion of a CORESET, such as a specific set of PRBs in the first two symbols in a specific time slot. Multiple PDCCH candidates may be received in a PDCCH resource using the same or different aggregation levels. The duration of a PDCCH resource may be the duration of a CORESET.

[0113] Two different PDCCH resources may be associated with the same CORESET and search space set, or may be associated with the same CORESET but different search space sets, or may be associated with different CORESETs but the same search space set, or may be associated with different CORESETs and search space sets.

[0114] In some cases, a PDCCH resource is equivalent to or identical to a "PDCCH monitoring occasion" as defined, for example, in 38.213. In some cases, a PDCCH monitoring occasion refers to a time domain component of a PDCCH resource.

[0115] Figure 2The diagram illustrates 7 PDCCH resources (abbreviated as PR 1-PR 7 in the figure) in a BWP in 4 consecutive time slots. The PDCCH resource index is added for illustration purposes. There may not be any explicit index or numbering of PDCCH resources. 2 CORESETs (C1 and C2) and 3 corresponding search space sets (S1, S2 and S3) are shown. The first search space set (S1) has a periodicity of 1 time slot, starting from the beginning of the time slot and is associated with CORESET C1. The second search space set (S2) has a periodicity of 2 time slots, starting from the beginning of the time slot and is associated with CORESET C2 occupying a different PRB than the first CORESET C1. The third search space set (S3) also has a periodicity of 2 time slots, but has an additional time slot offset, starts from the middle of the time slot, and is also associated with CORESET C1. In other words, CORESET C1 is associated with two different search space sets (S1 and S3).

[0116] Time (in)sensitive DCI, repetition (in)sensitive DCI

[0117] The following terms are used in this article:

[0118] Time-sensitive and time-insensitive DCI

[0119] The time instance at which the UE performs the process after reception of the DCI generally depends on the time instance at which the corresponding PDCCH is received. For example, if the DCI schedules PUSCH transmission, the UE transmits the PUSCH a certain number of symbols or slots after the slot at which the PDCCH is received.

[0120] In some cases, the UE behavior also depends on in which symbol or symbols in the slot the PDCCH carrying the DCI is received. For example, if a PDCCH scheduling a PDSCH with a certain timing is received in the first symbol in the slot, the UE will receive the scheduled PDSCH using the TCI state indicated in the DCI. On the other hand, if the PDCCH is received later in the same slot, for example in symbol 7, the UE will receive the scheduled PDSCH using the default TCI state.

[0121] DCI may be time-insensitive within a certain time interval. This means that the UE behavior indicated by the DCI is the same regardless of the symbol (within the time interval) on which the DCI is sent / received. On the other hand, if the UE behavior indicated by the DCI depends on the symbol (within the time interval) on which the DCI is sent / received, then the DCI is time-sensitive.

[0122] For example, if the corresponding PDCCH is received during any symbol within a slot, the UE behavior may be the same, but if the PDCCH is received in another slot, the UE behavior may be different.

[0123] Note that the DCI of certain DCI formats may be time-sensitive in some cases and may be time-insensitive in some cases.

[0124] In some cases, it may not be defined whether a DCI is time-sensitive or time-insensitive.

[0125] Note that the last symbol of the PDCCH may be equivalent to the last symbol of the PDCCH resources used to receive the PDCCH (or PDCCH candidate).Similarly, the first symbol of the PDCCH may be equivalent to the first symbol of the PDCCH resources used to receive the PDCCH (or PDCCH candidate).

[0126] Repeat-sensitive and repeat-insensitive DCI

[0127] For repetition-sensitive DCI, the UE behavior will be different if the UE receives multiple (repeated) identical DCIs simultaneously instead of a single DCI. For repetition-insensitive DCI, the UE behavior does not change. Two DCIs can be considered identical if the DCI format, RNTI, and all parameter values ​​are the same.

[0128] For example, consider a UE that receives repeated DCI with activation of a semi-persistently scheduled UL grant simultaneously. This DCI will be repetition insensitive because the repeated activation results in activation, which is the same behavior as without repetition.

[0129] In another example, consider a UE that receives repeated DCI with TPC commands while the UE is performing TPC command accumulation. The DCI will be repetition sensitive because repeated TCP commands will result in multiple accumulations, which results in different UE behavior than when the DCI is not repeated.

[0130] In some cases, for example, whether a DCI is repetition-sensitive or repetition-insensitive may not be defined in the specification, for example, the corresponding UE behavior may not be described, or described as being determined by the UE.

[0131] Multi-TRP transmission of PDCCH is a use case for improving PDCCH reliability. However, the network topology may be transparent to the UE, which means that the UE may not be able to distinguish different TRPs from different beams. This means that the method in this article is also applicable to single TRP transmission of PDCCH, such as PDCCH transmission of multiple Tx beams across a single TRP or a combination of multiple Tx beams from multiple TRPs. In addition, the method in this article can also be applied to the case of having PDCCH repetitions on the same beam. In addition, it is also applicable to the case of having a combination of PDCCH repetitions on a specific beam and across different beams or TRPs. For simplicity, the term multi-TRP PDCCH is used in this article, and it should be understood that it also includes the above cases.

[0132] The method in this article can be applied to the serving cell of the UE. The method can be applied to the scenarios of self-scheduling (PDCCH sent in a cell schedules transmission in the same cell) or cross-carrier scheduling (PDCCH sent in a cell schedules transmission in another cell).

[0133] For simplicity, the method described herein mainly uses the example of transmission from two TRPs (eg, two different values ​​of the CORESET parameter CORESETPoolIndex). However, the method can be easily applied to the case of more than two TRPs or a single TRP.

[0134] The examples with RRC Information Elements (IEs) and parameters in this document are from NR specification 38.331.

[0135] A TCI state may include one or more pieces of QCL information. A piece of QCL information may indicate one or more RSs and associated QCL types, for example, which information may be estimated or derived from the RSs. If a first TCI state includes a first RS sent from a first TRP and a second TCI state includes a second RS sent from a second TRP, the TCI state may be associated with the corresponding TRP.

[0136] Overview of the method for multi-TRP PDCCH

[0137] Various approaches to the multi-TRP PDCCH problem are presented. Consider the following framework.

[0138] Frame 1

[0139] The method is based on the assumption that a CORESET can have at most one active TCI state ID.

[0140] Frame 2

[0141] The method is based on the assumption that a CORESET can have multiple activated TCI state IDs.

[0142] Other methods

[0143] Various other methods related to multi-TRP (multi-TCI) PDCCH are discussed. For example, if the DCI is repeated between multiple TDMedPDCCH candidates (e.g., with different TCI state IDs), the reference timing may become an issue. The following discloses that the method can be based on the definition of reference resources.

[0144] In many cases, the TCI state used to receive the PDSCH can be based on the TCI state of the most recently monitored CORESET or the TCI state of the CORESET carrying the scheduling DCI. When the PDCCH is associated with multiple TCI states, various related problems arise. Various methods and systems that can solve these problems are presented below.

[0145] Architecture 1: Activate a TCI state for each CORESET

[0146] Overview

[0147] In Framework 1, it is assumed that for a CORESET, at most one TCI state can be activated into a UE. Even if TCI state reconfiguration and switching is possible for a CORESET, this may not be sufficient (e.g. not fast enough) to enable PDCCH reception on both TCI states, which would enable dual TRP PDCCH, since TCI state switching / reconfiguration also involves PDCCH.

[0148] Therefore, in framework 1, the transmission and reception of a PDCCH with two TCI states is achieved by involving multiple CORESETs, where each CORESET is associated with at most one TCI state.

[0149] There are several ways to implement dual TRP PDCCH transmission, for example to improve reliability. The methods can be classified, for example, as follows: 1) sending the same DCI with the same parameter value on two different PDCCH resources, for example, the DCI is repeated; 2) sending independent DCI in two different PDCCH resources; or 3) sending a single PDCCH carrying the DCI across two PDCCH resources. Regarding sending two independent DCIs in two different PDCCH resources, the independent DCIs can still involve the same type of UE action (for example, dynamic scheduling of PDSCH or PUSCH). The parameters in the independent DCIs can have the same or different values.

[0150] Regarding a single PDCCH carrying DCI transmitted across two PDCCH resources, the PDCCH may be mapped to CCEs in two different PDCCH resources.

[0151] In the related art, it has been supported to configure multiple CORESETs in a BWP. In other words, the UE can receive PDCCHs from multiple TRPs. However, these PDCCHs carry different DCIs, which means that the reliability of a single DCI cannot be enhanced through the diversity of multi-TRP reception. Different DCIs may mean that the UE processes the DCI as different DCIs. The various methods in this article address this shortcoming of the related art.

[0152] Presented below is a baseline framework for PDCCH reception from two TRPs in a BWP with one activated TCI state per CORESET. The network configures a set of TCI states in the BWP, e.g., in the configuration of the PDSCH (e.g., in the PDSCH-Config IE), where each TCI state (e.g., a list of TCI-State IEs) is configured with a TCI state ID (e.g., TCI-StateId IE). The network configures a first set of TCI states for the first CORESET in the BWP and a second set of TCI states for the second CORESET in the BWP. The first set of TCI states may include a first subset of TCI states corresponding to transmissions from the first TRP, a second subset of TCI states corresponding to transmissions from the second TRP, or a third subset of TCI states corresponding to simultaneous transmissions from multiple (e.g., two) TRPs. Similarly, the second CORESET may include such subsets. Note that one or more of these subsets may be empty. For example, the third subset if simultaneous transmissions from two TRPs are not used. In another example, a CORESET is configured with TCI states from a single TRP (e.g., a first or second TRP). Note that the subsets may be transparent to the UE, e.g., the UE may not know which set (if any) a particular TCI state belongs to. Note that the configuration of a set of TCI states for a CORESET in a BWP may be achieved by configuring a list of TCI state IDs, which may involve TCI states and TCI state IDs configured for a PDSCH in the same BWP. The network may also configure a CORESET pool index (e.g., CORESETPoolIndex) for some CORESETs in the BWP, such as all CORESETs. Different CORESETs configured in a BWP may be configured with the same or different CORESET pool indexes. For example, a first subset of CORESETs in a BWP may be configured with a first CORESET pool index, and a second subset of CORESETs in the BWP may be configured with a second CORESET pool index. In some cases, a first subset of CORESETs having the same CORESET pool index is configured with a TCI state corresponding to a first TRP, while a second subset of CORESETs having the same CORESET pool index is configured with a TCI state corresponding to a second TRP.

[0153] In Framework 1, it is assumed that at most one TCI state can be activated for a CORESET. If a CORESET is configured with multiple TCI states (e.g., by configuring multiple TCI state IDs), the MAC can activate one of these TCI states. For at least some of the CORESETs configured in the same BWP, different TCI states (e.g., different TCI state IDs) are activated simultaneously. For example, a first activated TCI state for a first CORESET in a BWP may correspond to a transmission from a first TRP, and a second activated TCI state for a second CORESET in a BWP may correspond to a transmission from a second TRP. If a CORESET is configured with a single TCI state, that TCI state may be applied to the CORESET (e.g., for the CORESET to be activated) without the need for activation by a MAC CE. In one example, 4 CORESETs are configured in a BWP. For the BWP, a first set of TCI states corresponding to transmissions from a first TRP is configured, and a second set of TCI states corresponding to transmissions from a second TRP is configured. For two of the CORESETs, TCI states from the first group are configured, while for the other two CORESETs, TCI states from the second group are configured. If a CORESET has been configured with more than one TCI state, but the TCI state has not been activated, the UE may assume that the DM-RS antenna ports associated with PDCCH reception and the SS / PBCH blocks identified by the UE during the initial access procedure are quasi-co-located.

[0154] Continuing with the baseline framework, the UE receives a PDCCH on a PDCCH resource, the reception being based on the activated TCI state of the corresponding CORESET. For example, the UE assumes that the DM-RS antenna port associated with the PDCCH reception in the PDCCH resource is quasi-co-located with one or more DL RSs configured by the activated TCI state.

[0155] A UE that successfully receives a PDCCH addressed to the UE, such as one where the scrambling of the CRC matches the RNTI monitored by the UE, will typically follow the DCI carried by the PDCCH. In a related art system, a UE that receives multiple PDCCHs each carrying a DCI will typically follow each DCI. However, in some cases, the UE may discard the DCI, for example, if the information is invalid or inconsistent.

[0156] For example, for any HARQ process ID in a given scheduling cell, it is not expected that a UE receives a PDSCH that overlaps in time with another PDSCH. In other words, two DCIs scheduling two PDSCHs that overlap in time at least should indicate different HARQ process IDs.

[0157] In one example, a UE may receive two PDCCHs in a BWP, each carrying a consistent DCI, and each DCI scheduling a PDSCH transmission that overlaps in time with another PDSCH, where the DCI parameters (e.g., allocated time and frequency resources, RV or MCS) are the same except for the HARQ process ID. In some cases, the downlink allocation index (DAI) in the two DCIs, such as the counter portion of the DAI, also needs to be different to make the DCIs consistent, for example, if the two PDCCHs are received in the same PDCCH monitoring opportunity. In such a case, the two DCIs will be consistent and valid, and the UE will expect two independent overlapping PDSCHs.

[0158] In another example, for any HARQ process ID in a given scheduling cell, it is not expected that a UE sends a PUSCH that overlaps in time with another PUSCH. In addition, for a given HARQ process, it is not expected that a UE is scheduled to send another PUSCH (e.g., by DCI format 0_0, 0_1, or 0_2 scrambled with C-RNTI or MCS-C-RNTI) before the expected transmission of the last PUSCH for that HARQ process ends. The expected transmission of the last PUSCH of the HARQ process. In other words, two DCIs that schedule at least two PUSCHs that overlap in time should at least indicate different HARQ process IDs to be valid.

[0159] It is important to be able to schedule a single PDSCH or PUSCH transmission, also in some cases where the DCI is repeated. To this end, in some cases, DCI repetition across multiple PDCCHs sent in different PDCCH resources does not appear to cause any problems on the UE or network side, for example, for the case where the DCI schedules PDSCH or PUSCH that overlap in time on the same HARQ process and multiple PDCCHs are received in the same one or more symbols. If the UE successfully receives only a single DCI, it follows that DCI. In some cases, if the UE successfully receives multiple DCIs, each scheduling a PDSCH or PUSCH that overlaps in time on the same HARQ process, the UE may discard all but one DCI because they would be invalid or inconsistent. After the other DCIs are discarded as invalid, the remaining valid DCIs may be determined to be valid. Figure 3 The diagram in Figure 2 illustrates this process. Figure 3: An illustration of a process for a UE to handle an inconsistent set of DCIs. In step 201, the UE successfully decodes a set of DCIs. In step 202, the UE evaluates whether the DCIs in the set are consistent and valid, one by one and collectively. For example, a first DCI may be consistent / valid itself, but it may be inconsistent / invalid with respect to a second DCI in the set, for example because it schedules the first PDSCH on resources that overlap with a second PDSCH scheduled by the second DCI on the same HRAR process ID. See step 203. In step 204, the UE discards DCIs from the set according to certain criteria. For example, the UE first discards any DCI that is inconsistent / invalid itself. Secondly, the UE discards any DCI that is consistent / valid itself, but is inconsistent / invalid with respect to another DCI in the set, for example, in the order in which the DCIs were received or in the order in which the CORESET IDs on which the DCIs were received or in the reverse order. Step 205, follow the set of DCIs.

[0160] However, in some cases, the UE successfully receives and decodes a set of DCIs, each scheduling a PDSCH or PUSCH that overlaps in time on the same HARQ process, the UE may discard all of the DCIs because they will all be invalid / inconsistent. In this case, the multi-TRP PDCCH may not work properly because it is generally more likely that multiple PDCCHs will be successfully received than that only a single PDCCH will be successfully received. The method and system are disclosed below.

[0161] In addition to the example of PDSCH and PUSCH scheduling, as described above, there are a variety of other uses of DCI carried by PDCCH, some of which are briefly discussed below. In general, if multiple identical DCIs are received in the same symbol or symbols, this should not cause any ambiguity unless otherwise indicated.

[0162] The purpose of the DCI carried by the PDCCH can be the scheduling, activation or release of semi-persistent scheduling (SPS) of PDSCH or SPS of PUSCH (e.g., UL grant type 2 in NR). In some cases, the UE is expected to respond to the SPS PDSCH release by providing HARQ-ACK information N symbols after the last symbol of the PDCCH providing the SPS PDSCH release. Therefore, a UE that receives multiple identical activation or release commands with SPSs with different last symbols may feel ambiguous.

[0163] The purpose of the DCI carried by the PDCCH may be PDCCH monitoring indication and the sleep / non-sleep behavior of the SCell.

[0164] The purpose of the DCI carried by the PDCCH may be search space set switching. The search space set switching time may depend on which time slot the DCI is received in. Therefore, a UE that receives multiple identical search space set switching indications in different time slots may feel ambiguous.

[0165] The purpose of the DCI carried by the PDCCH may be HARQ-ACK information for PUSCH transmission. The validity of the PUSCH HARQ-ACK information conveyed in the DCI may depend on the timing of the first symbol of the PDCCH carrying the DCI. Therefore, a UE that receives multiple identical HARQ-ACK indications in PDCCHs with different first symbols may feel ambiguous.

[0166] The DCI carried by the PDCCH may be used for paging and system information change notification or group common time slot format indication.

[0167] The purpose of the DCI carried by the PDCCH can be used for group common downlink preemption indication. The timing of the preempted symbol in the indication depends on the timing of the first symbol of the PDCCH carrying the DCI. Therefore, a UE that receives multiple preemption indications in PDCCHs with different first symbols may feel ambiguous.

[0168] The purpose of the DCI carried by the PDCCH can be used for group common UL cancellation indication. The timing of the cancelled symbol in the indication depends on the timing of the last symbol of the PDCCH carrying the DCI. Therefore, a UE that receives multiple cancellation indications in PDCCHs with different last symbols may feel ambiguous.

[0169] The purpose of the DCI carried by the PDCCH can be used for group common PUCCH, PUSCH and SRS TPC commands. If TPC accumulation is enabled, and if the UE receives multiple identical TPC commands, the UE may accumulate power multiple times according to the multiple TPC commands, even if the DCI is received in the same symbol or symbols. This may be a problem, for example, if the network just wants to send a single TPC command with higher reliability by using a multi-TRP PDCCH.

[0170] Multi-TRP transmission of a group-common PDCCH can be part of a beam scan of a group-common PDCCH, where the UE is configured to receive a subset of beams / TRPs, such as two beams.

[0171] Note that, in general, any time-frequency relationship between multiple PDCCH resources is considered herein, such as time multiplexing, frequency multiplexing, or spatial multiplexing, as well as fully or partially overlapping PDCCH resources in time or frequency. The following discusses the cases of time multiplexing, frequency multiplexing, and spatial multiplexing of PDCCH resources.

[0172] TDM of PDCCH resources

[0173] In some cases, PDCCH resources are multiplexed in time (TDmed), for example, multiplexed in multiple sets of partially overlapping or non-overlapping symbols in a time slot. In some cases, TDMed PDCCH resources are associated with different TCI state IDs (through corresponding CORESETs), and the different TCI state IDs can correspond to different TRPs or beams. Figure 4 The TDM of two PDCCH resources is illustrated in FIG.

[0174] TDM of PDCCH with different TCI states over multiple sets of non-overlapping symbols has the benefit that the UE can receive a single TCI state at a time, which can simplify the UE implementation. For example, analog Rx beamforming using a single UE antenna panel with a single receiver chain can be used. Such a UE can receive a first PDCCH resource using a first Rx beam and then switch to a second RX beam to receive a second PDCCH resource.

[0175] Figure 4 is an example of a TDMed PDCCH resource. The first PDCCH resource is associated with CORESET X1, search space set Y1, and activated TCI state Z1, while the second PDCCH resource is associated with CORESET X2, search space set Y2, and activated TCI state Z2.

[0176] CORESET's FDM

[0177] In some cases, PDCCH resources are frequency multiplexed (FDMed), for example, multiplexed in multiple sets of partially overlapping or non-overlapping PRBs. In some cases, FDMed PDCCH resources are associated with different TCI state IDs (through corresponding CORESETs), which may correspond to different TRPs or beams. Figure 5 The FDM of two PDCCH resources is illustrated in FIG.

[0178] FDM of PDCCH with different TCI states has the benefit that the UE can receive PDCCH associated with different TCI states at once, which can reduce latency. Another benefit may be that in case of repeated PDCCH across FDMed PDCCH resources, there is no uncertainty on the network side about the time instance of PDCCH reception. This can simplify the communication protocol. However, simultaneous reception of different TCI states (e.g. transmissions on different beams or from different TRPs) may require more complex UE implementation.

[0179] Figure 5 is an example of FDMed PDCCH resources. Figure 5 In (a) and (b), the first PDCCH resource is associated with CORESET X1, search space set Y1, and activated TCI state Z1, while the second PDCCH resource is associated with CORESET X2, search space set Y2, and activated TCI state Z2. In (a), the two PDCCH resources are contiguous in frequency ("localized"). In (b), the two PDCCH resources are non-contiguous in frequency ("distributed"). In (b), the PDCCH resources are interleaved.

[0180] CORESET's SDM

[0181] In some cases, PDCCH resources are spatially multiplexed (SDMed), for example, multiplexed in partially overlapping or overlapping time-frequency resources. In some cases, SDMed PDCCH resources are associated with different TCI state IDs (through corresponding CORESETs), and the different TCI state IDs can correspond to different TRPs or beams.

[0182] SDM of PDCCH with different TCI states has the benefit of using fewer time-frequency resources compared to TDM and FDM. A disadvantage may be that the UE may have to be able to receive simultaneously in multiple TCI states in the same time-frequency resources to fully gain the performance benefits of this scheme, which may mean higher UE complexity. Receiving multiple TCI states in the same time-frequency resources may correspond to receiving simultaneously with multiple Rx beams in the same time-frequency resources.

[0183] Method and system based on repetition sets

[0184] In some cases, DCI is repeated across PDCCH resources without pre-notifying the UE or making the UE aware of this, for example through configuration. Soft combining of DCI can be disabled in such cases, but allows greater network flexibility. Some such cases are discussed below.

[0185] In some cases, the UE expects that the DCI may be repeated across multiple (eg, two) PDCCH resources, for example, some PDCCHs in different PDCCH resources may carry the same DCI. Different ways of configuring this association between PCCH candidates are discussed below.

[0186] If the UE knows that the same DCI may be repeated across PDCCH resources, this allows the UE to soft combine PDCCH candidates across PDCCH resources in order to improve decoding performance. However, since there may be many PDCCH candidates in a PDCCH resource, the blind decoding workload may be high if the UE needs to soft combine many combinations of PDCCH candidates across PDCCH resources. Different ways to reduce the number of PDCCH candidate combinations are also discussed below.

[0187] UE determination of duplicate sets

[0188] In some cases, the UE may receive multiple identical DCIs during a time period (e.g., a slot, half a slot, or a few symbols). Reception of one or more of these DCIs may result in the same UE behavior, for example if the DCI is repetition-insensitive and time-sensitive within the time period (see discussion of time (in)sensitive DCI, repetition (in)sensitive DCI). In some cases, the UE behavior may be different depending on which one or more of the multiple DCIs it receives and correctly decodes, for example if the DCI is repetition-sensitive or time-sensitive within the time period. In this case, one approach is to let the network handle this uncertainty in UE behavior.

[0189] Another approach to addressing the duplication problem of repetition-sensitive or time-sensitive DCI is to enable the UE to detect the duplication, thereby avoiding the problem of duplicate or ambiguous UE actions. Thus, in some cases, the UE may determine that a successfully decoded DCI is a duplicate and then treat it as such. In various examples, successfully decoded DCI belonging to the same repetition set may be considered as a duplicate DCI by the UE. On the other hand, two successfully decoded DCIs belonging to different repetition sets or not belonging to a repetition set may not be considered as duplicates by the UE.

[0190] In various cases, a repetition set includes a set of PDCCH candidates. The UE may determine whether two successfully decoded DCIs may be considered as repetitions (e.g., belonging to the same repetition set) based on whether the DCI is carried on a PDCCH received on a PDCCH candidate belonging to the same repetition set. This may occur, for example, if the UE does not perform soft combining of PDCCH candidates, which may be appropriate, for example, the UE does not know whether the network will send a PDCCH with DCI repetitions.

[0191] The UE may evaluate one or more conditions to determine whether multiple successfully decoded DCIs belong to the same repetition set. In some cases, the UE evaluates one or more conditions before DCI decoding, such as to perform DCI merging or skip some PDCCH candidates after successfully decoding the DCI in the set. The UE may also evaluate one or more conditions to determine whether multiple PDCCH candidates (e.g., received or to be received) belong to the same repetition set.

[0192] In various cases, the repetition set may only include PDCCH candidates from the same BWP. In some cases, the repetition set may include PDCCH candidates from different BWPs (eg, from different serving cells).

[0193] The following lists example conditions for determining whether multiple DCIs (or corresponding PDCCH candidates) belong to the same repetition set. In the example, the DCI formats are the same. In some cases, if the PDCCH candidates are configured to receive at least one DCI format that is the same across candidates, they can be included in the same repetition set.

[0194] In the example condition, the DCI format is of a certain type, for example, some DCI formats may be repeated, but other formats are not. In some cases, the DCI formats that may be repeated may be configurable. For example, repetition may only be considered for DCI formats 0_1, 0_2, 1_1, and 1_2.

[0195] In the example conditions, in multiple DCIs, some or all DCI parameter values ​​are the same. In some cases, not all DCI parameter values ​​need to be the same. For example, for dynamic scheduling of PDSCH, repetition can be determined even if one or more of the PUCCH-related DCI parameters are different. PUCCH-related parameters may include: PUCCH resource indicator (PRI), PDSCH to HARQ feedback timing indicator, or TPC command for scheduled PUCCH. In particular, for DCIs that schedule PDSCH, in some cases, the HARQ process ID is the same in multiple DCIs. In some cases, for example, when DCI is received at the same PDCCH monitoring opportunity, the downlink allocation index (DAI) is the same in multiple DCIs. In particular, for DCIs that schedule PUSCH, in some cases, the HARQ process ID is the same in multiple DCIs. In some cases, the value of the TCI parameter (for example, in DCI format 1_1 or 1_2) may be different between multiple DCIs. In some cases, the value of the SRS resource indicator parameter (eg, in DCI format 0_1 ​​or 0_2) may be different between multiple DCIs. In some cases, which DCI parameters need to be the same may be configurable.

[0196] In an example condition, for example, the UE action indicated by the DCI is the same even if the DCI parameter values ​​are different. This may happen, for example, if the DCI is received in different time instances and thus contains different time-related parameter values, such as the time offset until the scheduled DL or UL transmission.

[0197] In an example condition, the RNTIs are the same. In some cases, if the PDCCH candidates are configured to monitor at least one RNTI that is the same across candidates, they may be included in the same repetition set.

[0198] In the example condition, the RNTI types are the same. In some cases, if the PDCCH candidates are configured to monitor at least one RNTI type that is the same across candidates, they may be included in the same repetition set. Example types are C-RNTI, MCS-C-RNTI, CS-RNTI, TPC-PUCCH-RNTI, TPC-PUSCH-RNTI, TPC-SRS-RNTI, INT-RNTI, SFI-RNTI, SP-CSI-RNTI, P-RNTI, SI-RNTI, RA-RNTI, or Temporary C-RNTI.

[0199] In the example condition, the RNTI type is of a certain type, for example, DCI / candidates corresponding to some RNTI types may be repeated, but other types are not. In some cases, the RNTI types that may be repeated may be configurable. For example, only PDCCH candidates on which C-RNTI, MCS-C-RNTI, or CS-RNTI are monitored are included in the repetition set.

[0200] In an example condition, DCI is received in a search space set of the same type.

[0201] In an example condition, DCI is received in a certain type of search space set, for example, duplicates are detected for some search space set types, but not for other search space set types. Example types are common search space (CSS) set, UE-specific search space (USS) set, Type0-PDCCH CSS set, Type0A-PDCCH CSS set, Type1-PDCCH CSS set, Type2-PDCCH CSS set, Type3-PDCCH CSS set. In some cases, the search space set types for which duplicates can be detected are configurable.

[0202] In the example condition, the CCE aggregation levels of the PDCCH candidates carrying DCI are the same.

[0203] In example conditions, a PDCCH carrying DCI is received within a time window, such as: the same time slot; the same half time slot; the same set of consecutive symbols, for example, 1, 2, 3, 4, 5, 6 symbols; a time window in which DCI is time-insensitive; the symbol of the longest PDCCH among the PDCCHs carrying DCI; the PDCCHs carrying DCI completely overlap in time; multiple consecutive time slots (for example, the number of time slots indicated by the duration parameter in the search space set configuration); or a span or span gap. In addition, in terms of a time window, it can be a symbol within a time slot / half time slot / partial time slot spanned by a set of PDCCH resources, including or excluding any symbols between such PDCCH resources in various cases. The set of PDCCH resources can, for example, correspond to a set of CORESETs, which can be configurable (for example, according to one of the examples of CORESET association / linking below). The set of PDCCH resources may, for example, correspond to different CORESETs with different CORESETPoolIndex values, for example by combining the time window condition with the condition below regarding the UE being provided with a CORESETPoolIndex value of 0. In some cases, the time window in which DCI / PDCCH candidates may belong to the same repetition set is configurable, such as in some of the examples above.

[0204] In an example condition, on an activated DL BWP for a serving cell, the UE is provided with a CORESETPoolIndex of 0 for one or more first CORESETs and a CORESETPoolIndex of 1 for one or more second CORESETs. In some cases, for example, in a time window as in the conditions above regarding time windows, PDCCH resources corresponding to different values ​​of CORESETPoolIndex may be in the same repetition set. In some cases, if there are multiple CORESETs with the same CORESETPoolIndex, the CORESET with the highest or lowest CORESET ID may be included in the repetition set. In some cases, multiple PDCCH resources corresponding to the same value of CORESETPoolIndex may be included in the repetition set.

[0205] In an example condition, DCI is received in different CORESETs. In an example condition, DCI is received using the same search space set.

[0206] In the example conditions, in some cases, the repeated set D i,nCI may include PDCCH candidates (from a set of PDCCH resources), f(m s,nCI,s,c,p,L)=i. In various cases, the repetition set only includes PDCCH candidates of the same aggregation level. In other cases, the repetition set may include PDCCH candidates of different aggregation levels, for example, a PDCCH candidate with aggregation level L1 in the first PDCCH resource and a PDCCH candidate with aggregation level L2 in the second PDCCH resource, L1≠L2.

[0207] οs is the index of the search space set of PDCCH resources in the group of PDCCH resources.

[0208] oc is the CORESET identifier of the PDCCH resource in the set of PDCCH resources (for example, defined by IEControlResourceSetId).

[0209] οp is the CORESETPoolIndex of the PDCCH resource in the group of PDCCH resources.

[0210] οL is the CCE aggregation level.

[0211] ONCI is the carrier indicator field value, which is the same for PDCCH candidates in a repetition set.

[0212] οm s,nCI is the PDCCH candidate index for a particular aggregation level L in search space s. Note that in some cases, for search space set s, the index m of the first PDCCH candidate for aggregation level L1 is s,nCI The index m of the second PDCCH candidate at aggregation level L2 (≠L1) may be equal to s,nCI In some cases, for aggregation level L and carrier indicator nCI, there is no more than one search space set s with a specific index m. s,n_CI PDCCH candidates, for example, m s,N,CI =0, ..., m s,NCI L -1, where m s,NCI L is the number of PDCCH candidates that the UE is configured to monitor for aggregation level L of search space set s for the serving cell corresponding to nCI. In some cases, PDCCH candidates are counted for each CORESET instead, e.g., for CORESET c, the candidate index may instead be m_(c,n_CI). This may be a more appropriate index for the case where a search space set is associated with multiple CORESETs.

[0213] ο Yes One or more functions in that map to a value i, where i can be an integer. For example, Or alternatively, In other words, the repeating set Is a set of PDCCH resources with index (or For the case where the repetition set may include PDCCH candidates of different aggregation levels, D i,nCI can include all the entries from the same index m s,nCI =i(or m c,nCI = i). On the other hand, for the case where the repetition set may only include PDCCH candidates of the same aggregation level, the symbol D i,nCI,L may be more appropriate, because the repeated set D i,nCI,L Include only aggregation level L with index m s,nCI =i(or m c,nCI =i) PDCCH candidates.

[0214] In some cases, the repetition sets are at least partially configurable. In an example configurable case, a search space set may be configured with an association with multiple CORESETs. This results in multiple PDCCH resources with at least the first symbol overlapping in time. Depending on the configuration of the CORESETs, these multiple PDCCH resources may use different frequency resources, or partially or completely overlap in frequency, e.g., as described below. For example, a second associated CORESET may be configured in a search space set configuration such as shown in Table 1. Note that additional conditions that PDCCH candidates belong to the same repetition set may apply, e.g., according to one or more of the above conditions.

[0215] In an example configurable case, PDCCH candidates in PDCCH resources corresponding to different CORESETs but the same search space set may be included in the same repetition set.

[0216] In some cases, the function (see above) is configurable.

[0217] In the example configurable case, Table 1 is an example of adding multiple CORESET associations in the search space set configuration IE, such as "controlResourceSetId2-rl7ControlResourceSetId OPTIONAL,--Need R".

[0218] Table 1

[0219]

[0220] In an example configurable case, multiple search space sets are linked by explicit configuration, e.g., as in Table 2. PDCCH candidates in PDCCH resources corresponding to linked search space sets may belong to the same repetition set. Note that in addition to the search space set linking, additional conditions for PDCCH candidates to belong to the same repetition set may apply, e.g., according to one or more of the above conditions.

[0221] Table 2 is an example implementation of adding a search space set link in the search space set configuration IE, such as “linkedSearchSpace-rl7 SearchSpaceId OPTIONAL,--Need R” in Table 2.

[0222] Table 2

[0223]

[0224]

[0225] In an example configurable case, multiple CORESETs are linked by explicit configuration, e.g., as in Table 3. PDCCH candidates in PDCCH resources corresponding to the linked CORESETs may belong to the same repetition set. Note that in addition to CORESET linking, additional conditions for PDCCH candidates to belong to the same repetition set may apply, e.g., according to one or more of the above conditions.

[0226] Table 3 is an example implementation of adding a CORESET link in the CORESET configuration IE, such as "linkedControlResourceSet-rl7 ControlResourceSetId OPTIONAL,--Need R" in Table 3.

[0227] Table 3

[0228]

[0229]

[0230] In an example configurable case, a list of CORESETs or a list of search space sets may be configured, for example in a PDCCH-Config IE as in Table 4. PDCCH candidates in PDCHH resources corresponding to linked CORESETs or search space sets may belong to the same repetition set. Note that in addition to CORESET linking, additional conditions for PDCCH candidates to belong to the same repetition set may apply, for example, according to one or more of the above conditions.

[0231] Table 4 is an example implementation of linking CORESETs through a configuration list.

[0232] Table 4

[0233]

[0234]

[0235] In an example configurable case, a CORESET or search space set may be configured for repetition, e.g., for inclusion in a repetition set, by including an "enable" parameter in a CORESET configuration (e.g., as shown in Table 5) or similarly in a search space set configuration. PDCCH candidates in PDCCH resources corresponding to a search space set or CORESET for which DCI repetition is enabled may belong to a repetition set. Note that in addition to enabling repetition for a CORESET / search space set, additional conditions for PDCCH candidates to belong to the same repetition set may apply, e.g., according to one or more of the above conditions.

[0236] Table 5 is an example implementation of enabling DCI repetition in CORESET (similar implementation can be applied to search space set configuration).

[0237] Table 5

[0238]

[0239] In another example, by including one or more parameters for monitoring the timing in the time domain, such as the parameters monitoringSlotPeriodicityAndOffset, duration or monitoringSymbolsWithinSlot, the search space set can be configured to repeat, for example, so as to be included in the repetition set. Table 6 and in the examples of Tables 7 and 8, a second monitoringSymbolsWithinSlot parameter (MonitoringSymbolsWithinSlot2-r17) can be configured. If so, repetition can be enabled. In some cases, the second parameter adds additional monitoring opportunities to the time slot defined by monitoringSlotPeriodicityAndOffset and duration. These additional monitoring opportunities may need to be non-overlapping in some cases, and do not overlap with the monitoring opportunities defined by monitoringSymbolsWithinSlot. In some cases, the PDCCH resources in the monitoring opportunities added between two consecutive monitoring opportunities defined by monitoringSlotPeriodicityAndOffset by monitoringSlotPeriodicityAndOffset2-r17 can be included in the repetition set together with the monitoring opportunities immediately before these opportunities. Consider the example of a 2-symbol CORESET associated with a search space set. The network configures two monitoring opportunities in the time slot defined by monitoringSlotPeriodicityAndOffset and duration, for example in symbol 0-1 and symbol 7-8. This can be achieved by configuring monitoringSymbolsWithinSlot="10000001000000". Now, the network configures additional monitoring opportunities by configuring monitoringSymbolsWithinSlot2-rl7="00100000010000" which adds monitoring opportunities in symbols 2-3 and symbols 9-10. Since the monitoring opportunity in symbol 2-3 is between consecutive opportunities in symbol 0-1 and symbols 7-8, the PDCCH resources in symbols 0-1 and symbols 2-3 can be included in the repetition set.

[0240] With further reference to the previous example, in Table 8, a second CORESET may be optionally configured. For Framework 1, this means that a second TCI state (e.g., a TCI state activated for a second CORESET) may be applied to PDCCH transmissions within a repetition set. For example, the TCI state ID activated for the first CORESET configured by controlResourceSetId may be a first TCI state ID (e.g., index t=0), and the TCI state ID activated for the second CORESET configured by controlResourceSetId2-rl7 may be a second TCI state ID (e.g., index t=1). These two TCI state IDs (T=2) may be associated with different PDCCH resources (or corresponding PDCCH monitoring opportunities) in a repetition set. Let the PDCCH resources or opportunities be indexed as m=0, ..., Ml, where M is the number of PDCCH resources or PDCCH monitoring opportunities within a repetition set. In some cases, T activated TCI state IDs are cyclically allocated to PDCCH resources or PDCCH monitoring opportunities within a repetition set, for example, T TCI state IDs are continuously allocated to resources / opportunities m=0, ..., T-1 and m=T, ..., 2T-1, etc., assuming that T <M。

[0241] In some cases, T activated TCI state Ids are allocated such that a first TCI state Id index (t=0) is allocated to multiple (e.g., V) consecutive PDCCH resource indices (or timing indices) (e.g., m=0, ..., V-1, where V=floor(M / T) or V=ceil(M / T)), a second TCI state Id index (t=1) is allocated to the next, e.g., V consecutive PDCCH resource indices (or timing indices), and so on, until the last TCI state Id index (t=T-1) is allocated to the last consecutive PDCCH resource index (or timing index) (e.g., m=V(T-1), ..., M-1). Note that in addition to the conditions described here, additional conditions that PDCCH candidates belong to the same repetition set may apply, e.g., according to one or more of the above conditions.

[0242] Table 6

[0243]

[0244]

[0245]

[0246] Table 7

[0247]

[0248]

[0249] Table 8

[0250]

[0251]

[0252]

[0253] Table 7 illustrates such a situation.

[0254] Note that in addition to the conditions described here, additional conditions that PDCCH candidates belong to the same repetition set may apply, for example, according to one or more of the conditions described above.

[0255] In the example of Table 6, a second monitoringSlotPeriodicityAndOffset parameter (monitoringSlotPeriodicityAndOffset2-rl7) may be configured. If so, repetition may be enabled. In some cases, the regular duration and monitoringSymbolsWithinSlot parameter values ​​may be applied to the additional opportunities defined by monitoringSlotPeriodicityAndOffset2-rl7.

[0256] In another example, by including one or more parameters for monitoring the timing in the time domain, such as the parameters monitoringSlotPeriodicityAndOffset, duration or monitoringSymbolsWithinSlot, the search space set can be configured to repeat, for example, so as to be included in the repetition set. In Tables 7-9, the second monitoringSymbolsWithinSlot parameter (monitoringSymbolsWithinSlot2-rl7) can be configured. If so, repetition can be enabled. In some cases, the second parameter adds additional monitoring opportunities to the time slot defined by monitoringSlotPeriodicityAndOffset and duration. These additional monitoring opportunities may need to be non-overlapping in some cases, and do not overlap with the monitoring opportunities defined by monitoringSymbolsWithinSlot. In some cases, the PDCCH resources in the monitoring opportunities added between two consecutive monitoring opportunities defined by monitoringSlotPeriodicityAndOffset through monitoringSlotPeriodicityAndOffset2-rl7 can be included in the repetition set together with the monitoring opportunities immediately before these opportunities.

[0257] Consider the example of a 2-symbol CORESET associated with a search space set. The network configures two monitoring opportunities in the time slot defined by monitoringSlotPeriodicityAndOffset and duration, for example in symbol 0-1 and symbol 7-8. This can be achieved by configuring monitoringSymbolsWithinSlot="10000001000000". Now, the network configures additional monitoring opportunities by configuring monitoringSymbolsWithinSlot2-rl7="00100000010000" which adds monitoring opportunities in symbols 2-3 and symbols 9-10. Since the monitoring opportunity in symbol 2-3 is between consecutive opportunities in symbol 0-1 and symbols 7-8, the PDCCH resources in symbols 0-1 and symbols 2-3 can be included in the repetition set.

[0258] In Table 7, a second CORESET may be optionally configured. For framework 1, this means that a second TCI state (e.g., a TCI state activated for the second CORESET) may be applied to PDCCH transmissions within a repetition set. For example, the TCI state ID activated for the first CORESET configured by controlResourceSetId may be the first TCI state ID (e.g., index t=0), and the TCI state ID activated for the second CORESET configured by controlResourceSetId2-rl7 may be the second TCI state ID (e.g., index t=1). These two TCI state IDs (T=2) may be associated with different PDCCH resources (or corresponding PDCCH monitoring opportunities) in a repetition set. Let the PDCCH resources or opportunities be indexed as m=0, ..., Ml, where M is the number of PDCCH resources or PDCCH monitoring opportunities within a repetition set. In some cases, T activated TCI state IDs are cyclically allocated to PDCCH resources or PDCCH monitoring opportunities within a repetition set, for example, T TCI state IDs are continuously allocated to resources / opportunities m=0, ..., T-1 and m=T, ..., 2T-1, etc., assuming that T <M。

[0259] In some cases, T activated TCI state Ids are allocated such that a first TCI state Id index (t=0) is allocated to multiple (e.g., V) consecutive PDCCH resource indices (or timing indices) (e.g., m=0, ..., V-1, where V=floor(M / T) or V=ceil(M / T)), a second TCI state Id index (t=1) is allocated to the next, e.g., V consecutive PDCCH resource indices (or timing indices), and so on, until the last TCI state Id index (t=T-1) is allocated to the last consecutive PDCCH resource index (or timing index) (e.g., m=V(T-1), ..., M-1). Note that in addition to the conditions described here, additional conditions that PDCCH candidates belong to the same repetition set may apply, e.g., according to one or more of the above conditions.

[0260] Table 8 illustrates such a case. Note that in addition to the conditions described here, additional conditions that PDCCH candidates belong to the same repetition set may apply, for example, according to one or more of the above conditions.

[0261] In the example of Table 6, a second monitoringSlotPeriodicityAndOffset parameter (monitoringSlotPeriodicityAndOffset2-rl7) may be configured. If so, repetition may be enabled. In some cases, the regular duration and monitoringSymbolsWithinSlot parameter values ​​may be applied to the additional opportunities defined by monitoringSlotPeriodicityAndOffset2-rl7.

[0262] Table 6 illustrates an example implementation of enabling DCI repetition in a search space set.

[0263] In the examples of Tables 8 and 9, a second monitoringSymbolsWithinSlot parameter (monitoringSymbolsWithinSlot2-rl7) can be configured. If so, repetition can be enabled. In some cases, the second parameter adds additional monitoring opportunities to the time slot defined by monitoringSlotPeriodicityAndOffset and duration. These additional monitoring opportunities may need to be non-overlapping in some cases and non-overlapping with the monitoring opportunities defined by monitoringSymbolsWithinSlot. In some cases, the PDCCH resources in the monitoring opportunities added between two consecutive monitoring opportunities defined by monitoringSlotPeriodicityAndOffset by monitoringSlotPeriodicityAndOffset2-rl7 can be included in the repetition set together with the monitoring opportunities immediately preceding these opportunities.

[0264] Consider the example of a 2-symbol CORESET associated with a search space set. The network configures two monitoring opportunities in the time slot defined by monitoringSlotPeriodicityAndOffset and duration, for example in symbol 0-1 and symbol 7-8. This can be achieved by configuring monitoringSymbolsWithinSlot="10000001000000". Now, the network configures additional monitoring opportunities by configuring monitoringSymbolsWithinSlot2-rl7="00100000010000" which adds monitoring opportunities in symbols 2-3 and symbols 9-10. Since the monitoring opportunity in symbol 2-3 is between consecutive opportunities in symbol 0-1 and symbols 7-8, the PDCCH resources in symbols 0-1 and symbols 2-3 can be included in the repetition set.

[0265] In Table 8, a second CORESET may be optionally configured. For framework 1, this means that a second TCI state (e.g., a TCI state activated for a second CORESET) may be applied to PDCCH transmissions within a repetition set. For example, the TCI state ID activated for the first CORESET configured by controlResourceSetId may be the first TCI state ID (e.g., index t=0), and the TCI state ID activated for the second CORESET configured by controlResourceSetId2-rl7 may be the second TCI state ID (e.g., index t=1). These two TCI state IDs (T=2) may be associated with different PDCCH resources (or corresponding PDCCH monitoring opportunities) in a repetition set. Let the PDCCH resources or opportunities be indexed as m=0, ..., M1, where M is the number of PDCCH resources or PDCCH monitoring opportunities within a repetition set. In some cases, T activated TCI state IDs are cyclically allocated to PDCCH resources or PDCCH monitoring opportunities within a repetition set, for example, T TCI state IDs are continuously allocated to resources / opportunities m=0, ..., T-1 and m=T, ..., 2T-1, etc., assuming that T <M。

[0266] In some cases, T activated TCI state Ids are allocated such that a first TCI state Id index (t=0) is allocated to multiple (e.g., V) consecutive PDCCH resource indices (or timing indices) (e.g., m=0, ..., V-1, where V=floor(M / T) or V=ceil(M / T)), a second TCI state Id index (t=1) is allocated to the next, e.g., V consecutive PDCCH resource indices (or timing indices), and so on, until the last TCI state Id index (t=T-1) is allocated to the last consecutive PDCCH resource index (or timing index) (e.g., m=V(T-1), ..., M-1). Note that in addition to the conditions described here, additional conditions that PDCCH candidates belong to the same repetition set may apply, e.g., according to one or more of the above conditions.

[0267] Table 7 illustrates an example implementation of enabling DCI repetition in a search space set. Table 8 illustrates an example implementation of enabling DCI repetition in a search space set.

[0268] In another example illustrated in Tables 9 and 10, by including a repetition parameter, such as repetitionfactor-rl7 below, the search space set can be configured to repeat, for example, to be included in a repetition set. Values ​​n2, n3, etc. can correspond to 2 repetitions, 3 repetitions, etc.

[0269] Table 9

[0270]

[0271]

[0272] For example, each "original" monitoring opportunity defined by (monitoringSlotPeriodicityAndOffset, duration, and monitoringSymbolsWithinSlot) may be repeated in the first available symbols (e.g., DL or DL / variable symbols) after that monitoring opportunity. In some cases, the UE repeats the monitoring opportunity in the symbol immediately following the original opportunity, and skips the repetition if it happens to collide with another signal (which has a higher priority in the specification) or if it falls in an UL symbol. In various cases, the PDCCH resources in the original monitoring opportunity and the subsequently repeated monitoring opportunity may be included in the repetition set.

[0273] In the example of Table 10, a second CORESET may be optionally configured. This may provide a second TCI state, similar to that described above with respect to Table 7. TCI state ID allocation for different PDCCH resources or PDCCH monitoring occasions may follow the description with respect to Table 8.

[0274] Table 10

[0275]

[0276] Note that in addition to the conditions described here, additional conditions that PDCCH candidates belong to the same repetition set may apply, for example, according to one or more of the conditions described above.

[0277] Table 9 illustrates an example implementation of enabling DCI repetition in a search space set.

[0278] Table 10 illustrates an example implementation of enabling DCI repetition in a search space set.

[0279] DCI repetition may be enabled for a cell or for a BWP by configuration, for example by RRC parameters in the PDCCH Config IE such as in Table 11.

[0280] Table 11 illustrates example parameters for enabling DCI repetition in the PDCCH-Config IE.

[0281] Table 11

[0282]

[0283] In various cases, the UE uses one or more of these conditions to determine whether the PDCCH candidate or successfully decoded DCI belongs to the same repetition set, such as using an "AND" or "OR" operation between the conditions, and in some cases adds one or more additional conditions not listed here.

[0284] For simplicity, a few examples with two DCI / PDCCH resources are:

[0285] Example: Two successfully decoded DCIs are considered duplicates if all of the following conditions are met.

[0286] • Enable DCI repetition for BWP.

[0287] Both DCIs are received in USS.

[0288] • Both DCIs have CRC scrambled with the same RNTI.

[0289] Both DCIs use the same DCI format.

[0290] The parameter value is the same in both DCIs.

[0291] Both DCIs are received within a certain time window.

[0292] Both DCIs have the same PDCCH candidate index m s1,nCI =m s2,nCI s1 and s2 are the indices of the search space set on which the DCI was received, and nCI is the carrier indicator field value, which is the same for both DCIs.

[0293] Example lb: If all of the following conditions are met, two PDCCH candidates are considered to belong to the duplication set.

[0294] • Enable DCI repetition for BWP.

[0295] • Two PDCCH candidates correspond to the USS.

[0296] • The UE monitors DCI with CRC scrambled with the same RNTI on both PDCCH candidates.

[0297] • The UE monitors DCI with the same DCI format on both PDCCH candidates.

[0298] Both PDCCH candidates are received within a certain time window.

[0299] • The two PDCCH candidate indices are the same, for example, m_(s_1, n_CI) = m_(s_2, n_CI), where s1 and s2 are the indices of the search space sets on which the PDCCH candidates were received, and nCI is the carrier indicator field value, which is the same for both candidates.

[0300] Example 2a: Two successfully decoded DCIs are considered duplicates if all of the following conditions are met.

[0301] • Enable DCI repetition for the UE.

[0302] Both DCIs are received in USS.

[0303] • Both DCIs have CRC scrambled with the same RNTI.

[0304] Both DCIs use the same DCI format.

[0305] • If a DCI schedules DL or UL data transmission, the HARQ process ID is the same in both DCIs.

[0306] Both DCIs are received within a certain time window.

[0307] • The DCI is received on a CORESET with a different CORESET pool index.

[0308] Example 2b: If all of the following conditions are met, two PDCCH candidates are considered to belong to the duplication set.

[0309] • Enable DCI repetition for the UE.

[0310] • Two PDCC candidates correspond to the USS.

[0311] • The UE monitors DCI with CRC scrambled with the same RNTI on two PDCCH candidates.

[0312] • The UE monitors DCI with the same DCI format on two PDCCH candidates.

[0313] Both PDCCH candidates are received within a certain time window.

[0314] • Two PDCCH candidates are received on CORESETs with different CORESET pool indices.

[0315] In some cases, a UE may anticipate DCI repetitions across a set of PDCCH candidates based on one or more conditions (eg, as in the example above).

[0316] In various cases, the UE may not expect the DCI to be repeated within the PDCCH resource, for example, if the repetition set contains no more than one PDCCH candidate from the PDCCH resource.

[0317] In some cases, this means that the UE may expect that a DCI carried by a PDCCH on one of the PDCCH candidates in such a set is repeated on each PDCCH candidate in the set. This may allow soft merging of the PDCCH candidates in the set with reasonable UE complexity, but this will reduce PDCCH transmission flexibility on the network side. Alternatively, this may allow the UE to skip receiving or decoding the remaining PDCCH candidates in the set once it has successfully decoded a DCI from a PDCCH candidate in the set, since the UE expects the remaining PDCCH candidates in the repetition set to carry only DCI repetitions of the already decoded DCI.

[0318] In some cases, the UE may expect one or more of the following:

[0319] · PDCCH transmission without duplication (DCI is carried by one PDCCH sent on one PDCCH candidate in the repetition set but not on other PDCCH candidates),

[0320] PDCCH transmission with partial repetition (the DCI is carried by multiple PDCCHs sent on a subset of the PDCCH candidates in the repetition set, rather than all PDCCH candidates), or

[0321] • PDCCH transmission with full repetition (DCI is carried by a PDCCH sent on every PDCCH candidate in the repetition set).

[0322] This would allow flexibility on the network side for non-repetitive DCI (e.g., single TRP transmission of PDCCH), some DCI repetition (e.g., “some TRP” transmission of PDCCH), or full DCI repetition (e.g., “all TRP” transmission of PDCCH).

[0323] Some DCIs are time sensitive (see above). Methods and systems to address this issue are described in more detail below.

[0324] Example UE Procedure

[0325] Fig. 6A and Figure 6BAn example UE process is illustrated in FIG. Upon PDCCH reception and successful decoding of two DCIs (e.g., step 211 or step 221), the UE evaluates whether the two DCIs belong to the same repetition set (e.g., steps 212 and 213 or steps 223 and 224). If so, they are processed as a single DCI, which can solve the problem of repetition-sensitive DCI (see below). If not, the DCIs are processed separately, for example, the UE follows the instructions of each DCI. Fig. 6A and Figure 6B The difference between Figure 6B An additional check is included to determine whether the DCI repetition feature is enabled, such as in Table 10 and step 222. The process is easily generalized from two DCIs to multiple DCIs. As shown, Fig. 6A (Step 211-Step 215) and Figure 6B (Step 221 - Step 226 ) illustrates an example of a process performed by a UE to determine DCI repetition.

[0326] Figure 7 Another example process is illustrated in (step 231-step 235), Figure 7 The diagram illustrates a UE process that may be performed in order to determine PDCCH candidates for soft combining. In step 231, the UE determines whether DCI repetitions have been configured. In some examples where such an enabling configuration is not present, step 231 may be omitted. In steps 232 and 233, the UE evaluates whether two PDCCH candidates belong to the same repetition set. If so, the UE receives and decodes these PDCCH candidates using soft combining (step 234). The UE may also receive and decode PDCCH candidates without soft combining. After step 234, the UE may also process successfully decoded DCIs as single DCIs. If repetitions are not configured, or the PDCCH candidates do not belong to the same repetition set, the UE may receive and decode the PDCCH candidates individually, for example, without soft combining (step 235). After step 235, the successfully decoded DCIs may be processed individually (step 236).

[0327] Figure 8The diagram illustrates a UE process in which the UE can skip receiving or decoding some PDCCH candidates, thereby reducing UE power consumption. In step 241, the UE determines whether DCI repetition is configured. If not, the UE proceeds to step 247 and, for example, receives or decodes each PDCCH candidate individually according to the process of the related art. On the other hand, if DCI repetition is configured, the UE can proceed to determine the repetition set, for example as described above. In step 244, the UE can receive or decode one or more remaining PDCCH candidates (if any) in the repetition set, for example, candidates that have not yet been received or decoded. For example, if some PDCCH candidates in the repetition set are distributed in different TDMed PDCCH resources, the UE can receive or decode them in time sequence. If some of these PDCCH candidates overlap in time, they can be received at the same time, but some associated processing and decoding can still be performed sequentially, for example, channel estimation, equalization, demodulation or decoding. If none of these received / decoded PDCCH candidates in the repetition set is successfully decoded, and there are remaining PDCCH candidates in the repetition set, the UE receives or decodes one or more of these PDCCH candidates again. On the other hand, if one of the PDCCH candidates is successfully decoded, the UE may proceed to step 246, where the UE may skip receiving or decoding the remaining PDCCH candidates in the repetition set. The end step means completion of receiving and decoding the PDCCH candidates in the repetition set. Note that the repetition set may be localized in time, such as within a certain time slot. Thus, the UE may repeatedly perform the process or a portion thereof over time. In particular, steps 242-247 may be repeated over time, and new repetition sets may be received or decoded. Note also that step 241 may be optional, or may not be repeated. Typically, some PDCCH candidates may belong to a repetition set, while other PDCCH candidates do not belong to a repetition set. Thus, the UE may perform the process according to steps 224-247 for such PDCCH candidates, while simultaneously performing individual PDCCH candidate reception and decoding for candidates that do not belong to the repetition set.

[0328] Method and system for UE selection based on DCI in DCI set

[0329] In various cases, the UE receives and successfully decodes multiple DCIs and may discard one or more of them. In some cases, the UE may discard all DCIs except one DCI. In some cases, the UE may discard all DCIs except a few (e.g., 2 or 3) DCIs.

[0330] In various cases, the UE may choose which DCI(s) to discard and which DCI(s) to act upon.

[0331] In various cases, the UE may determine a repetition set, such as described above.The UE may determine a DCI set as a set of DCIs that are successfully decoded from PDCCH candidates belonging to the repetition set.

[0332] For example, a repetition set may include, for example, two PDCCH candidates corresponding to two different TRPs. When the network sends repeated DCI on two PDCCH candidates or sends different DCI on two PDCCH candidates, the UE can, for example, successfully decode the DCI from either or both PDCCH candidates depending on the radio conditions. This means that if only the DCI carried on the first PDCCH candidate is successfully decoded, the DCI set contains the DCI carried on the first PDCCH candidate. If only the DCI carried on the second PDCCH candidate is successfully decoded, the DCI set contains the DCI carried on the second PDCCH candidate. If both DCIs are successfully decoded, the DCI set contains the DCI carried on the first PDCCH candidate and the DCI carried on the second PDCCH candidate.

[0333] Note that the DCIs in a DCI set may be the same (eg, same DCI format, RNTI, parameter values, etc.) or different (eg, one or more of the DCI format, RNTI, and parameter values ​​are different).

[0334] In one example, the DCI carried in the repetition set (and thus the DCI in the DCI set) may include some of the same parameters, e.g., parameters corresponding to the reception of the PDSCH, e.g., one or more of: carrier indicator; frequency domain resource allocation; time domain resource allocation; VRB to PRB mapping; PRB bundling size indicator; rate matching indicator; MCS; new data indicator; redundancy version; number of HARQ processes; antenna port; CBG transmission information; CBG clearing information; DMRS sequence initialization; or TCI.

[0335] For example, parameters that may differ between DCI carried in a repetition set may include parameters related to subsequent UL transmissions, such as HARQ-ACK, PUCCH, or CSI-related parameters, such as one or more of: a TPC command for a scheduled PUCCH; a PUCCH resource indicator; or a PDSCH-to-HARQ_feedback timing indicator.

[0336] In some cases, the transmission configuration indicator (TCI) value may be different in different DCIs in a repetition set.

[0337] Note that in some cases, scheduling PDSCH with DCI may mean in this context that PDSCH is sent with some form of repetition scheme (different TCI states may be applied sequentially or cyclically to different repetitions), such as one of the schemes described in 38.214: "FDMSchemeA"; "FDMSchemeB"; "TDMSchemeA" (intra-slot repetition); "TDM scheme B" (e.g., "When the UE is configured by the upper layer parameter PDSCH-config, the upper layer parameter PDSCH-config indicates a PDSCH containing RepNumR16 in PDSCH-TimeDomainResourceAllocation"); h-TimeDomainAllocationList”, which can correspond to inter-slot repetition); or “SDM scheme” (for example, “when the DCI field ‘time domain resource allocation’ is not used to indicate the DCI field ‘time domain resource allocation’ to the UE (the DCI field ‘time domain resource allocation’ indicates the entry in the pdsch-TimeDomainAllocationList containing RepNumR16 in PDSCH-TimeDomainResourceAllocation), but the two TCI states in the code point of the DCI field ‘transmission configuration indication’ and the DM-RS port indication within the two CDM groups in the DCI field ‘antenna port’ are used”).

[0338] In some cases, the UE will successfully decode multiple DCIs in the repetition set, for example, the corresponding DCI set will include multiple DCIs. In some cases, multiple DCIs will schedule the same PDSCH, for example, the PDSCH-related parameters will be the same in the DCIs within the DCI set. In some cases, multiple DCIs will schedule PDSCHs with the same properties using different parameters, for example, if the DCIs are received in different PDCCH monitoring opportunities.

[0339] However, the DCIs for scheduling PDSCH in a DCI set may include different indications in other aspects. In an example, different DCIs indicate different PUCCH resources, such as by different values ​​of "PUCCH resource indicator" or "PDSCH-to-HARQ_feedback timing indicator". In another example, different DCIs indicate different PUCCH TPC commands, such as by different values ​​of "TPC command for scheduled PUCCH".

[0340] By indicating different PUCCH resources (which may correspond to different UE Tx beams with different spatial relationship configurations), the network can introduce spatial diversity in subsequent PUCCH transmissions. Subsequent PUCCH transmissions may be used for HARQ-ACK.

[0341] For example, consider the case of a repeated set with two PDCCH candidates, the two PDCCH candidates are sent by two different TRPs, each PDCCH carries DCI scheduling the same PDSCH, such as Fig. 9 As shown in the diagram. However, the two DCIs indicate different PUCCH resources. Consider the case where the UE only successfully decodes the first DCI sent by the first TRP, but fails to successfully decode the second DCI sent by the second TRP. In this case, the UE will use the first PUCCH resource indicated by the first DCI. This PUCCH resource may correspond to a UE Tx beam pointing to the first TRP. This may be advantageous if the link between the second TRP and the UE is blocked. In another case, only the DCI from the second TRP is successfully decoded. In this case, the UE will use the second PUCCH resource as indicated in the second DCI. The UE Tx beam configured for the second PUCCH resource can advantageously be pointed to the second TRP through previous configuration and indication. In other words, by having different DCIs in the DCI sets sent from different TRPs indicate different PUCCH resources associated with the beams pointing to the corresponding TRPs, the reliability of the PUCCH after the scheduled PDSCH can be improved. This improved PUCCH reliability may be achieved at least for cases where there is a correlation between PDCCH reliability and the corresponding PUCCH reliability, such as when the PDCCH is transmitted in the same frequency band as the PUCCH.

[0342] Fig. 9 This is an illustration of the case where, for the special case where PDCCH, PDSCH and PUCCH are in the same BWP (eg, also the same carrier), two PDCCHs indicate the same PDSCH but different PUCCH resources.

[0343] In some cases, the UE may successfully decode multiple DCIs in a repetition set, for example, the corresponding DCI set will include multiple DCIs. In this case, these DCIs may include indications for different PUCCH resources. In some cases, the UE will send multiple indicated PUCCHs. In other cases, the UE may select one or a subset of the PUCCH resources indicated by the DCI in the DCI set. The UE's selection of one or a subset of the DCIs whose contents the UE will follow may be based on a set of criteria. The criteria may include one or more of the following:

[0344] • Follow any successfully decoded DCI (no choice).

[0345] ·Use the measurement results of reference signals associated with different PDCCHs carrying DCIs in the DCI set to determine which DCI or DCIs to follow. For example, the UE can use the PDCCH DM-RS or the CSI-RS associated with the PDCCH, for example, the CSI-RS or SSB configured or indicated as quasi co-located (QCL) with the PDCCH DM-RS. The measurement result can be RSRP, RSRQ or SINR. In one example, the UE can use the DCI corresponding to the highest measurement result. In another example, the UE can select any DCI as long as its measurement result is above a threshold, and the threshold can be configurable.

[0346] • It is up to the UE to select which one or more DCIs to follow from the DCI set.

[0347] • The UE selects a DCI indicating a PUCCH resource that does not collide with another signal or channel.

[0348] • The UE selects the DCI indicating the PUCCH resource that results in the lowest latency or a latency within a certain latency limit.

[0349] The UE selects one or more DCIs to follow from the DCI set based on the UE capabilities. For example, if multiple DCIs indicate PUCCH resources that overlap in time, the UE may select these multiple DCIs if the UE is capable of sending overlapping PUCCHs, such as if the UE has multi-panel transmission capabilities.

[0350] In some cases, multiple DCIs in a DCI set indicate the same PUCCH resource. A PUCCH resource may be associated with multiple UL Tx beams. For example, a PUCCH resource may have two activated spatial relationship information (e.g., with PUCCH-SpatialRelationlnfoId), where each spatial relationship information may correspond to a UL Tx beam. Different activated spatial relationship information for a PUCCH resource may correspond to different TRPs. For example, different activated spatial relationship information for a PUCCH resource may be associated with different values ​​of a CORESET pool index (e.g., parameter CORESETPoolIndex). The UE may select one or both of the two activated spatial relationship information for the indicated PUCCH resource, for example based on one or more of the criteria set forth above. For example, if the UE successfully decodes only a single DCI, the UE may select the spatial relationship information associated with the same CORESET pool index as the CORESET on which the decoded DCI was received.

[0351] In addition to indicating the PUCCH resources, and possibly indirectly indicating the UE Tx beam used for the PUCCH, the DCI may also indicate different PUCCH TPC commands. In some cases, the UE may maintain separate power control loops (states) for different groups of PUCCH resources. Different groups of PUCCH resources may be associated with different CORESET pool indices, for example, different CORESET pool indices may have separate PUCCH transmit power control loops. If the UE receives a PUCCH TPC command in a successfully decoded DCI received on a CORESET with a CORESET pool index, the UE may apply the PUCCH TPC command to the power control loop associated with the same CORESET pool index.

[0352] Note that for the case where the UE can select DCI from multiple DCIs in the DCI set, the UE may also continue to receive and decode PDCCH candidates after having successfully decoded DCI from PDCCH candidates in the repetition set. This may be contrary to some of the examples given above, in which the UE skips the reception or decoding of some PDCCH candidates.

[0353] In some cases, the UE will successfully decode multiple DCIs in the repetition set, for example, the corresponding DCI set will contain multiple DCIs. In some cases, multiple DCIs will schedule the same PDSCH, for example, except for the indicated TCI, the PDSCH-related parameters will be the same in the DCIs in the DCI set. In some cases, the indicated TCI needs to be the same for DCIs received on PDCCH resources associated with the same CORESET pool index, for example, the indicated TCI may be different in DCIs received on PDCCH resources associated with different CORESET pool indices.

[0354] In some cases, the UE does not expect to be indicated with a greater number of different TCI states (across DCI corresponding to PDSCH transmissions, possibly including PDSCH repetitions) for a scheduled PDSCH (possibly including repetitions) than the maximum number of TCI states for such PDSCH transmissions, where the maximum number may be based on specifications, UE capabilities, or configuration from the network.

[0355] The UE may receive subsequent PDSCH based on a set of TCI states (eg, T DCI states) across different DCI indications.

[0356] For example, consider a repeating set with two PDCCH candidates. If the UE receives DCI only on the first candidate in the set, then when receiving the PDSCH, it can use the TCI indicated in the DCI carried on the first PDCCH candidate. Similarly, if the UE receives DCI only on the second candidate, then when receiving the PDSCH, it can use the TCI indicated in the second DCI. If the UE successfully receives DCI on both PDCCH candidates in the set, and the TCI indicates different TCI states, then when receiving the PDSCH, the UE can apply both TCI states. Assuming that the UE receives two DCIs (which should be the normal case), the network can send the PDSCH. If one link is blocked, both PDCCHs may be lost, but part of the subsequent PDSCH corresponding to the TCI state that was not received may also be lost.

[0357] In various cases, for example, PDCCHs received from different TRPs on different PDCCH resources schedule different PDSCH or PUSCH transmissions. Different PDSCHs or PUSCHs may carry the same transport block, such as different redundancy versions or different transport blocks. In some cases, these PDCCHs are received in a repetition set, even if the DCI repetition itself is not applicable in this case. However, the corresponding function of linking PDCCH candidates may be useful. For example, consider a UE receiving two PDCCHs that schedule different PDSCHs, such as time-multiplexed or frequency-multiplexed. In some cases, if two PDCCHs belong to the same repetition set, the UE expects the corresponding different PDSCHs to carry repetitions of the same transport block, such as using different redundancy versions (each PDCCH may schedule PDSCHs repeatedly). In various cases, the TCI state used to receive one of these PDSCHs is based on the PDCCH / DCI that schedules the corresponding PDSCH. Therefore, if the UE only correctly decodes one PDCCH (from one TRP), the UE may only receive the PDSCH using the TCI state based on that PDCCH. Note that if the DCI includes a TCI state indication, the PDCCH from the first TRP may indicate the TCI state corresponding to the second TRP, or indicate two TCI states corresponding to the first TRP and the second TRP, respectively. Therefore, as in the system of the related art, a single PDCCH from a TRP can be used to schedule multi-TRP PDSCH transmissions.

[0358] Framework 2: Multiple Activated TCI States per CORESET

[0359] Overview

[0360] In the various embodiments discussed above, there is no more than one activated TCI state for a CORESET. In Framework 2, the maximum number of activated TCI states for a CORESET is increased to more than one. Since TCI states can be associated with TRPs, multiple activated TCI states per CORESET means that the UE can receive one or more PDCCHs in PDCCH resources from multiple TRPs.

[0361] In some cases, multiple activated TCI states are applied to PDCCH candidates, for example, each PDCCH candidate corresponding to a CORESET. This means that multi-TRP diversity gain can also be obtained when a single PDCCH candidate is received.

[0362] Disclosed below are methods and systems for implementing multiple activated TCI states for PDCCH candidates based on applying different TCI states to different FDMed resources.

[0363] Disclosed below are methods and systems that may be based on applying multiple activation TCI states to overlapping resources (eg, SDMs).

[0364] The T TCI state IDs associated with a CORESET are sorted and indexed as t=0, ..., (T-1), where t is the TCI state ID index (not the TCI state ID) of the CORESET and T is the number of activated TCI state IDs of the CORESET.

[0365] For example, as described below, the activated TCI state IDs of the CORESET may be sorted (first TCI state ID, second TCI state ID, etc.) according to the sequential position in the MAC CE or the sequential position of the corresponding MAC CE.

[0366] FDM Scheme 2.1: TCI Status of Each REG Bundle

[0367] In various cases, a PDCCH candidate contains a set of CCEs. Different PDCCH candidates contain different sets of CCEs. In various cases, a CCE contains a set of REG bundles, such as 1, 2 or 3 REG bundles. In some cases, the UE may assume that the same precoding is used on the DL Tx side within a REG bundle, such as when the CORESET is configured with the parameter precoderGranularity set to sameAsREG-bundle. For some cases where a CORESET is associated with multiple TCI states, different TCI states may apply to different REG bundles within the CORESET.

[0368] For example, T TCI state IDs may be assigned to T REG bundles consecutively in frequency order and then cyclically assigned across all REGs of the CORESET, as illustrated in Table 4, where T = 2. If a REG bundle is assigned index i = 0, 1, 2, ..., (the number of REG bundles in the CORESET - 1), then REG bundle i may be assigned TCI state mod(i, T), where mod(a, b) is an "a modulo b" operation.

[0369] In another example, different TCI states are assigned to (approximately) the same number of consecutive REG bundles, e.g., similar to the PDCCH candidates described above. For example, when T=2, the REG bundles in the lower half (e.g., in terms of index or frequency) are assigned to the first TCI state t=0, while the REG bundles in the upper half are assigned to another TCI state t=1.

[0370] One advantage of TCI state assignment per REG bundle is that diversity provided by, for example, multiple TCI states corresponding to multiple TRPs may be obtained within a CCE.

[0371] Fig.10 The diagram illustrates the allocation of two TCI states (Z0 and Z1) per REG bundle for various CORESET configurations.

[0372] In some cases, TCI states are assigned to REG bundles by using a bitmap, for example, as shown in Table 12 (an example implementation of assigning TCI states to different REG bundles by using a bitmap). For example, the most significant (left) bit represents the first REG bundle (e.g., i=0), the second most significant (left) bit represents the second REG bundle (e.g., i=1), and so on. The length of the bitmap can be, for example, fixed (e.g., the maximum number of REG bundles in a CORESET) or flexible (e.g., equal to the number of REG bundles in a CORESET). The two bit values ​​can correspond to two TCI states, for example, "0" can correspond to the first active TCI state ID, and "1" can correspond to the second TCI state ID.

[0373] Table 12

[0374]

[0375] FDM solution 2.2: TCI status of each CCE

[0376] In some cases where a CORESET is associated with multiple (T) TCI state IDs, a TCI state may be assigned for each CCE.

[0377] Similar to the REG bundle described above, if the CCEs may be indexed as j=0, 1, ..., (the number of CCEs in the CORESET-1), for example, then a TCI state ID index mod(j, T) may be assigned to CCE j.

[0378] In another example, different TCI states are assigned to (approximately) the same number of consecutive CCEs, e.g., similar to the PDCCH candidates described above. For example, when T=2, the CCEs in the lower half (e.g., in terms of index or frequency) are assigned to a first TCI state t=0, while the CCEs in the upper half are assigned to another TCI state t=1.

[0379] In some cases, TCI states are assigned to CCEs by using a bitmap, for example, as shown in Table 13, which illustrates an example of an implementation of assigning TCI states to different REG bundles by using a bitmap. For example, the most significant (left) bit represents the first CCE (e.g., j=0), the second most significant (left) bit represents the second CCE (e.g., j=1), and so on. The length of the bitmap can be, for example, fixed (e.g., the maximum number of CCEs in a CORESET) or flexible (e.g., equal to the number of CCs in a CORESET). The two bit values ​​can correspond to two TCI states, for example, "0" can correspond to the first activated TCI state ID, and "1" can correspond to the second TCI state ID.

[0380] Table 13

[0381]

[0382] FDM solution 2.2: TCI status of each CCE

[0383] In some cases where a CORESET is associated with multiple (T) TCI state IDs, a TCI state may be assigned for each CCE.

[0384] Similar to the REG bundle described above, if the CCEs may be indexed as j=0, 1, ..., (the number of CCEs in the CORESET-1), for example, then a TCI state ID index mod(j, T) may be assigned to CCE j.

[0385] In another example, different TCI states are assigned to (approximately) the same number of consecutive CCEs, e.g., similar to the PDCCH candidates described below. For example, when T=2, the CCEs in the lower half (e.g., in terms of index or frequency) are assigned to a first TCI state t=0, while the CCEs in the upper half are assigned to another TCI state t=1.

[0386] In some cases, TCI states are assigned to CCEs by using a bitmap, e.g. Fig.11 As exemplified in Fig.11 The diagram illustrates an implementation of assigning TCI states to different CCEs using a bitmap. For example, the most significant (left) bit represents the first CCE (e.g., j=0), the second most significant (left) bit represents the second CCE (e.g., j=1), and so on. The length of the bitmap can be, for example, fixed (e.g., the maximum number of CCEs in a CORESET) or flexible (e.g., equal to the number of CCs in a CORESET). The two bit values ​​can correspond to two TCI states, for example, "0" can correspond to the first activated TCI state ID, and "1" can correspond to the second TCI state ID.

[0387] FDM scheme 2.3: TCI status of each RB subset contiguous in frequency

[0388] In some cases, the UE assumes that the same DL Tx precoder is used within a set of contiguous RBs, for example, when CORESET is configured with the parameter precoderGranularity set to allContiguousRBs.

[0389] Similar to the REG bundles and CCEs above, if the groups of consecutive RBs within CORESET can be indexed in frequency order as m=0, 1, ..., (the number of groups of consecutive RBs within CORESET1 - 1), then the TCI state ID index mod(m, T) can be assigned to the consecutive RB set m, for example. Fig.11 This is illustrated in FIG. 1 for the case of T=2 and two sets of consecutive RBs.

[0390] In another example, different TCI states are assigned to (approximately) the same number of consecutive groups of consecutive RBs, e.g., similar to the PDCCH candidates described above. For example, when T=2, the groups in the lower half (e.g., in terms of index or frequency) are assigned to a first TCI state t=0, while the groups in the upper half are assigned to another TCI state t=1.

[0391] SDM Scenario 2.4: Multiple SDMed TCI States per CORESET

[0392] In some embodiments in which multiple TCI state IDs can be activated for a CORESET, the multiple TCI state IDs are associated with the same PDCCH DMRS port. In other words, orthogonal time-frequency CORESET resources are not associated with different TCI state IDs, as in some of the schemes described above. Instead, multiple activated TCI state IDs are associated with the same resources (e.g., RBs of the CORESET). In practice, this may mean that multiple TRPs send PDCCHs on the same time-frequency resources, such as the same PDCCH, using the same DMRS sequence, for example. In some cases, different TCI state IDs may be associated with different DMRS sequences. For example, if up to two TCI state IDs can be activated for a CORESET, an optional second DMRS sequence may be configured for the CORESET, as shown in Table 14, which illustrates a CORESET with multiple configured DMRS sequences.

[0393] Table 14

[0394]

[0395] How to receive such a CORESET can be determined by the UE. If the UE has multi-panel reception capability, it can receive the CORESET using one TCI state ID on one panel and another TCI state ID on another panel. In other cases, the UE can select one of the TCI state IDs before PDCCH reception, for example, based on the measurement results of the RS included in multiple activated TCI states.

[0396] Multiplexing Scheme 2.5: TCI Status of Each PDCCH Candidate

[0397] In some cases, different PDCCH candidates in a PDCCH resource are associated with different TCI states. In one example, two TRPs may send the same DCI on two different PDCCH candidates on the same PDCCH resource. Depending on, for example, UE capabilities or the most recently estimated channel conditions, the UE may attempt to receive one or both PDCCH candidates.

[0398] In some cases, repetition sets may be defined for PDCCH candidates within a PDCCH resource (as described above) so that the UE can determine on which PDCCH candidates repetitions / duplications are expected.

[0399] In some cases, the association of the TCI state of each PDCCH candidate within a PDCCH resource is combined with repetition across multiple monitoring occasions.

[0400] For example, the PDCCH candidates in the PDCCH resources of aggregation level L may be indexed as Ms，NCI =0, ..., m s，NCI (L) -1, where m s，NCI (L) is the number of PDCCH candidates that the UE is configured to monitor for aggregation level L of search space set s for the serving cell corresponding to nCI (see above).

[0401] In some cases, T activated TCI state IDs associated with a PDCCH resource are cyclically allocated to PDCCH candidates, for example, T TCI state IDs are continuously allocated to candidate M. s，NCI = 0, ..., T-1 and M s，NCI =T, ..., 2T-1, etc., assuming that T <m s，NCI (L) .

[0402] In some cases, T activated TCI state IDs are allocated such that the first TCI state ID index (t=0) is allocated to a plurality of (eg, V) consecutive PDCCH candidate indices (eg, M s，NCI =0, ..., V-1, where or The second TCI state Id index (t=1) is allocated to the next, for example, V consecutive PDCCH candidate indexes, etc., until the last TCI state Id index (t=T-1) is allocated to the last consecutive PDCCH candidate index (for example, M s，NCI =V(T-1), ..., M s，NCI (L) )-1).

[0403] MAC CE used to activate multiple TCI states for CORESET

[0404] Example MAC CE for CORESET activating two TCI states

[0405] In various cases, multiple TCI states may be activated for a CORESET, for example, by a MAC CE indicating two TCI state IDs, as shown below. TCI state ID0 may correspond to the first activated TCI state for a CORESET, and TCI state ID1 may correspond to the second activated TCI state for a CORESET.

[0406] The TCI state indication of the UE-specific PDCCH MAC CE is identified by a MAC subheader with a logical channel ID (LCID). The logical channel ID may be a newly specified logical channel ID for activating multiple TCI states for a CORESET and distinguishing the MAC CE from a legacy MAC CE. It may have a fixed size of 24 bits with the following fields: serving cell ID, CORESET ID, TCI state IDi, or a reserved bit (e.g., R set to 0).

[0407] Serving Cell ID: This field indicates the identity of the serving cell to which the MAC CE is applied. The length of this field is 5 bits.

[0408] CORESET ID: This field indicates the control resource set for which the TCI state is indicated, for example, identified by ControlResourceSetId as specified in 38.331 [6]. When the value of the field is 0, this field refers to the control resource set configured by controlResourceSetZero as specified in 38.331 [6]. The length of this field is 4 bits.

[0409] TCI State IDi: This field indicates the i-th TCI state applicable to the control resource set identified by the CORESET ID field, for example, identified by TCI-StateId as specified in TS 38.331 [5]. If the field of CORESET ID is set to 0, this field indicates the TCI-stateId of the TCI state among the first 64 TCI states configured by tci-States-ToAddModList and tci-States-ToReleaseList in PDSCH-Config in the active BWP. If the field of CORESETID is set to a value other than 0, this field indicates the TCI-StateId configured by tci-StatesPDCCH-ToAddList and tci-StatesPDCCH-ToReleaseList in the control resource set identified by the indicated CORESET ID. The length of this field is 7 bits.

[0410] R: Reserved bit, set to 0.

[0411] Fig.12 An example illustrating an example indication of two TCI state IDs for a UE-specific PDCCH MAC CE.

[0412] In the case where more than two TCI State IDs are activated for a CORESET, the MAC CE may be extended by one additional octet per additional activated TCI State ID, where each additional octet may include a reserved bit R and 7 bits of the TCI State ID. In addition, the MAC CE may be variable-sized with a length indicator field, where the length indicator may indicate how many TCI State IDs are configured for the CORESET indicated by the CORESET ID field.

[0413] Activate two TCI states for CORESET by using multiple MAC CEs

[0414] In various cases, multiple TCI states (e.g., 2) may be activated for a CORESET by multiplexing multiple MAC CEs (e.g., 2) for CORESET TCI state ID activation into the same MAC PDU, where each of these multiple MAC CEs activates a single TCI state for the same serving cell (same serving cell ID in multiple MAC CEs) and CORESET (same CORESET ID in multiple MAC CEs), for example, by using MAC CEs. Note that a MAC PDU carrying multiple MAC CEs activating multiple TCI state IDs for a CORESET in a serving cell may also carry other MAC CEs activating single or multiple TCI states for other CORESETs or serving cells.

[0415] An example UE procedure is given below, with two indicated TCI states for simplicity. In a first step, the UE successfully decodes a PDSCH carrying at least one MAC CE for a TCI state indication for a UE-specific PDCCH MAC CE. In a second step, for each such MAC CE in the MAC PDU: a) determine (s,c): s = serving cell ID indicated in the MAC CE, c = CORESET ID; or b) if the number of activated TCI states for (s,c) is less than a maximum value (optional condition), activate the indicated TCI state ID of (s,c).

[0416] In various cases, for example, if the UE does not expect to have more than a maximum value of TCI state IDs activated for the serving cell and CORESET, the condition in step 2.b may be removed. The maximum value may be based on reported UE capabilities (e.g., the UE supports two activated TCI states for the CORESET) or network configuration (e.g., a maximum of two activated TCI states for the CORESET is allowed).

[0417] In the case where multiple TCI state IDs are activated for the CORESET, the TCI state IDs can be sorted based on the order (e.g., ordinal position) of the corresponding MAC CEs in the MAC PDU, so that one TCI state ID is the first activated TCI state ID for the CORESET, another TCI state ID is the second activated TCI state ID for the CORESET, and so on.

[0418] In some cases, the CORESET may be configured to operate with two activated TCI state IDs. If so, the UE may maintain a set of one or two activated TCI state IDs for the CORESET. If the UE receives a MAC CE to activate one TCI state ID, it activates the TCI state ID for the CORESET if the number of already activated TCI state IDs is less than two. If the number of already activated TCI state IDs for the CORESET is two, the UE still activates the newly received TCI state ID, but at the same time deactivates the already activated TCI state ID, such as the TCI state ID activated for the CORESET the longest time ago, or during the reception of the previous or preceding MAC PDU. If the UE receives activation for two TCI state IDs in the MAC PDU, the UE activates both TCI state IDs and deactivates the previously activated 1 or 2 TCI state IDs.

[0419] Reference PDCCH process

[0420] In some cases, the PDCCHs received on multiple PDCCH resources carrying repeated DCI are received in different groups of symbols. For example, the corresponding PDCCH resources may be as follows: Figure 4 In other cases, the PDCCH carrying the DCI is received via multiple PDCCH resources that may be TDMed (without PDCCH repetition).

[0421] Subsequent UE actions may depend on the timing of the received PDCCH that triggered the corresponding UE action.

[0422] For example, which QCL hypothesis or QCL assumptions to apply when receiving a PDSCH may depend on the time difference between the reception of the PDCCH carrying the scheduling DCI and the start of the scheduled PDSCH.

[0423] The DCI replicated across two time-multiplexed PDCCH resources may be successfully decoded in the first PDCCH resource, the second PDCCH resource, or both PDCCH resources.Therefore, there may be uncertainty on the network side as to what action the UE will take.

[0424] Similarly, for DCI received across multiple PDCCH resources (without repetition), it may not be clear which PDCCH resource to use as the timing reference.

[0425] To avoid this ambiguity, a reference PDCCH resource may be defined. The reference PDCCH resource may be the first (in time) PDCCH resource or the last (in time) PDCCH resource in a group of PDCCH resources.

[0426] The set of PDCCH resources may be a set of PDCCH resources that the UE considers for DCI repetition, for example, according to one of the examples of repetition sets above. For the example in which a time window is used as a condition for DCI repetition (as described above), the first and last PDCCH resources may refer to the first and last PDCCH resources (in time) within the time window, respectively.

[0427] For situations where time after PDCCH reception is critical, e.g., the timeline after reception of the PDCCH, the reference PDCCH resource may be the last PDCCH resource. For situations where time before PDCCH reception is critical, e.g., the timeline before reception of the PDCCH, the reference PDCCH resource may be the first PDCCH resource.

[0428] In some cases, a single DCI may have multiple reference resources, for example, if the DCI is such that it indicates UE behavior at a timeline before PDCCH reception and UE behavior at a timeline after PDCCH reception. In this case, both the first and last PDCCH resources may be reference resources for the DCI, and which reference resource to apply depends on the UE behavior under consideration (UE behavior for which time before PDCCH is critical, or UE behavior for which time after PDCCH is critical).

[0429] In one example, consider a case with two TDMed PDCCH resources that the UE considers for DCI repetition (e.g., repetition set). The repeated DCI has DCI format 1_1 with the TCI field present, which schedules a PDSCH. For the case of determining the QCL assumption for PDSCH reception, the time after PDCCH reception is critical. This is illustrated in Fig.13 middle, Fig.13A reference PDCCH resource is shown for the case where the QCL assumption for a subsequent scheduled PDSCH is determined. Since the corresponding timeline is based on the time after the PDCCH is received, the second PDCCH resource is used as the reference resource for this case. For this case, even if the DCI is received in the first PDCCH resource, the time between the PDCCH reception and the scheduled PDSCH is T2. Thus, the last PDCCH resource, e.g., the second PDCCH resource of the two TDMed PDCCH resources, is the reference resource. Regardless of whether the UE actually receives the DCI on the first PDCCH resource, the second PDCCH resource, or both PDCCH resources, the UE will use the second PDCCH resource as a reference when determining the QCL assumption for a subsequent scheduled PDSCH.

[0430] In another example, consider again the case of two TDMedPDCCH resources that the UE considers for DCI repetition (e.g., repetition set). The repeated DCI has DCI format 2_1, which can be used to indicate downlink preemption to the UE. For the case of preemption indication, the time before PDCCH reception is critical. This is illustrated in Fig.14 middle, Fig.14 A reference PDCCH resource is shown for the case of indication of preempted DL resources. Since the corresponding timeline is based on the time before PDCCH reception, the first PDCCH resource is used as the reference resource for this case. For this case, even if the DCI is received in the second PDCCH resource, the time between the preempted resource and the PDCCH reception is T1. Thus, the first PDCCH resource, for example the first PDCCH resource of two TDMed PDCCH resources, is the reference resource. Regardless of whether the UE actually receives the DCI on the first PDCCH resource, the second PDCCH resource, or both PDCCH resources, the UE will use the first PDCCH resource as a reference when determining the preempted resource.

[0431] Fig.15An exemplary UE process for determining one or more reference resources is illustrated. In step 251, the UE may determine, for example, a repetition set corresponding to several TDMed PDCCH resources. In step 252, in some cases, step 252 may be preceded by the UE successfully decoding one or more repetition DCIs in the repetition set. In steps 253 and 254, the UE determines whether there is a UE action indicated by the DCI for which time is critical before the PDCCH, and whether there is a UE action indicated by the DCI for which time is critical after the PDCCH. Note that the DCI may indicate two (or more) UE actions, one (or more) of which is such that time is critical before the PDCCH, and one (or more) of which is such that time is critical after the PDCCH. If one or both of the before / after are applicable, the UE selects one or both reference resources (step 255 or step 256). Note that if the UE action in the DCI is such that both the time before the PDCCH and the time after the PDCCH are relevant, the UE can select two reference resources: the earliest PDCCH resource in concentrated time, and the latest PDCCH resource in concentrated time. If neither the time before the PDCCH nor the time after the PDCCH is relevant, then there may be no need to select a reference resource, and the process can be terminated. For the above-mentioned from other perspectives, the case to be covered here is the case where the DCI indicates two UE actions. For the first UE action, the time before the PDCCH reception is relevant. Therefore, the first PDCCH resource in time will be an appropriate reference resource. For the second UE action, the time after the PDCCH reception is relevant. Therefore, the last PDCCH resource in time will be an appropriate reference resource. A solution may be to select two reference resources - the first PDCCH resource for the first UE action and the last PDCCH resource for the last UE action.

[0432] In some cases, the reference resource is the union of the PDCCH resources in the repetition set.In the case of no repeated PDCCH reception, the reference resource may be the PDCCH resource on which the DCI is received.

[0433] Default beam for PDSCH

[0434] In various schemes discussed herein, a UE may successfully decode a DCI that it receives associated with a multiple TCI state PDCCH reception. In an example, the successfully decoded DCI is carried by one or more PDCCHs in a repetition set (see above), where the PDCCH candidates in the repetition set are associated with different TCI states. In an example, the successfully decoded DCI is carried by a PDCCH associated with multiple TCI states, for example, it is received on a CORESET with multiple activated TCI states.

[0435] For brevity, such a case may be referred to as multi-TCI DCI. A successfully decoded DCI received on a PDCCH associated with a single TCI state may be referred to as a single-TCI DCI.

[0436] In some cases, for example, if "QCL-TypeD" is configured for at least one TCI state in the considered serving cell (e.g., QCL with respect to spatial Rx parameters), the UE assumption about the TCI state or QCL of the PDSCH may depend on the time offset between the reception of the DCI (e.g., the end of the PDCCH resources or the reference resources as described above) and the corresponding scheduled PDSCH. For example, if the time offset is equal to or greater than a threshold, the UE may use one assumption about the TCI state / QCL of the PDSCH, and if the time offset is less than the threshold, the UE may use another assumption. In some cases, the threshold may be configurable or based on UE capabilities that the UE has reported to the network, for example, based on the parameter timeDurationForQCL.

[0437] Note that in this document, the TCI state or QCL of the PDSCH may refer to the TCI state or QCL of the DM-RS of the PDSCH. The PDSCH may be in the same or different BWP or cell as the corresponding PDCCH or CORESET / PDCCH resources considered below.

[0438] In some cases, if the CORESET is configured with the enabled parameter tci-PresentInDCI or tci-PresentInDCI-ForFormat1_2, the DCI may include a DCI field "Transmission Configuration Indication", in short, the TCI field. The TCI field can be used to indicate one or more TCI states of the subsequent scheduled PDCSH.

[0439] In some cases, the UE receives a DCI that schedules one or more PDSCHs, which has a DCI format that does not cause the TCI field to be present. In some cases, if the time offset is also equal to or greater than the threshold, the UE may assume that the TCI state or QCL assumption of the PDSCH is the same as the TCI state or QCL assumption of the CORESET used for the transmission of the PDCCH carrying the DCI (whichever is applied). For example, if the scheduling DCI is a multi-TCI DCI, the TCI state associated with the reception of the scheduling DCI may be used as the TCI state / QCL assumption of the corresponding scheduled PDSCH.

[0440] Note that "TCI state or QCL assumption (whichever applies)" in some cases means that the CORESET does not have one or more TCI states activated. Instead, the UE may use another QCL assumption, for example based on the SSB determined during the initial access procedure relative to "QCL-TypeA" (e.g., QCL with respect to Doppler shift, Doppler spread, average delay, delay spread), and, when applicable, relative to "QCL-TypeD" (e.g., QCL with respect to spatial Rx parameters). The term "QCL assumption" may imply QCL with respect to a single or multiple different QCL types, or may refer to a single or multiple different RSs.

[0441] In some cases, if the time offset is less than a threshold, the UE may use a TCI state / QCL assumption for PDSCH that is used to receive the monitored PDCCH resources in the latest slot with monitored PDCCH resources in the active BWP. If the latest slot includes multiple monitored CORESETs, the TCI state / QCL assumption of the CORESET with the lowest CORESET ID (e.g., controlResourceSetId) in the latest slot may be used.

[0442] In some cases, if the time offset is less than a threshold and the UE is configured with two different values ​​of CORESETPoolIndex for the CORESETs in the BWP, the TCI state / QCL assumption that the UE may use for the PDSCH may depend on in which CORESET the PDCCH scheduling the PDSCH was received. The UE may use the TCI state / QCL assumption for the monitored PDCCH resources in the latest slot having the monitored PDCCH resources associated with the same CORESETPoolIndex as the CORESET on which the scheduling DCI was received. If the latest slot includes multiple monitored CORESETs with the same CORESETPoolIndex as the CORESET on which the scheduling DCI was received, the TCI state / QCL assumption of the CORESET with the lowest CORESET ID (e.g., controlResourceSetId) among these multiple CORESETs in the latest slot may be used. If the scheduling DCI is a multi-TCI DCI, the TCI state associated with the reception of the scheduling DCI may be used as the TCI state / QCL assumption for the corresponding scheduled PDSCH.

[0443] In the above various cases, multiple TCI states (eg, two) associated with the DCI scheduling the PDSCH may be used as the TCI state / QCL assumption for the scheduled PDSCH. This brings about various problems that are addressed below.

[0444] TCI state mapping to PDSCH DM-RS antenna port

[0445] One or more TCI states for the scheduled PDSCH are ordered and indexed as t=0,…,(T-1), where t is the TCI state ID index (not TCI state Id) and T is the number of activated TCI state IDs, for example based on the TCI state associated with the monitored PDCCH resources or scheduling DCI in the latest timeslot (see above).

[0446] For example, as described above, the activated TCI state IDs of the CORESET may be sorted according to the sequential position or index in the MAC CE, or the sequential position of the corresponding MAC CE (first TCI state ID, second TCI state ID, etc.).

[0447] In some cases, the multi-TCI DCI for scheduling PDSCH is carried by one or more PDCCHs in a repetition set, where the PDCCH candidates in the repetition set are associated with different TCI states. These TCI states can also be sorted and indexed, for example, in the order of time and frequency of the corresponding PDCCH resources, or in the order of the corresponding CORESET Id.

[0448] Note that the DCI may schedule PDSCH repeatedly, for example based on "FDMSchemeA", "FDMSchemeB", "TDMSchemeA" (intra-slot repetition), "TDM scheme B" (inter-slot repetition), or "SDM scheme" (see above).

[0449] Note also that the DCI may indicate a set of DM-RS antenna ports to be used for receiving the PDSCH via the DCI field "antenna port". Different antenna ports may be associated with different code division multiplexing (CDM) groups. Therefore, an indication of a set of DM-RS antenna ports may also, for example, implicitly indicate a set of CDM groups. Using a single TCI state for all antenna ports belonging to the same CDM group may be beneficial to communication performance. CDM groups may be indexed as λ=0, 1, ...

[0450] In some cases, one of T TCI states is used to receive a scheduled PDSCH, such as the first TCI state (t=0), eg, the same TCI state is applied to all scheduled antenna ports and CDM groups.

[0451] In some cases, if the number of scheduled CDM groups is one, the scheduled PDSCH is received using one of T TCI states, such as the first TCI state (t=0), for example, the same TCI state is applied to all scheduled antenna ports within a single CDM group.

[0452] In some cases, for example, when T>1, if the number of scheduled CDM groups is two, two of the T TCI states are used to receive the scheduled PDSCH, for example, the first TCI state (t=0) is applied to all antenna ports within the first scheduled CDM group (e.g., with the lowest CDM group index λ), and the second TCI state (t=1) is applied to all antenna ports within the second scheduled CDM group.

[0453] In some cases, one or more antenna ports belonging to each scheduled CDM group λ are indicated by the scheduling DCI. In some cases, when receiving PDSCH, the TCI state with Id index mod(λ+k,T) applies to CDM group λ, where mod(a,b) is an "a mod b" operation. In some cases, k=0, for example, the Id index is mod(λ,T). In some cases, k is the redundancy version used in the PDSCH transmission, for example, as indicated by the DCI field "Redundancy Version".

[0454] In some cases, T TCI states are applied to the scheduled CDM groups such that the first TCI state Id index is assigned to the scheduled CDM group with the lowest index, etc., and the highest TCI state Id index is assigned to the scheduled CDM group with the highest index. For example, when T=2, t=0 is assigned to CDM groups 0 and 1, and t=1 is assigned to CDM group 2. In another example, t=0 is assigned to CDM group 0, and t=1 is assigned to CDM groups 1 and 2.

[0455] In some cases where the PDSCH repetition scheme is configured or indicated by DCI, eg, as per one of the examples herein, the same TCI state is used in each repetition.

[0456] In some cases, such as when "TDMSchemeA" is enabled (e.g., the UE is configured by the upper layer parameter RepSchemeEnabler set to "TDMSchemeA"), the number of PDSCH transmission opportunities is derived from T. If T = 1, a single PDSCH transmission opportunity is used, and a single TCI state (e.g., t = 0) applies to PDSCH reception. If T = 2, two PDSCH transmission opportunities are used, and the first TCI state (e.g., t = 0) applies to the first PDSCH opportunity, and the second TCI state (e.g., t = 1) applies to the second PDSCH opportunity.

[0457] In some cases, the scheduled CDM group λ determines the TCI state. For example, if the DCI schedules CDM group λ=0, then the TCI state Id index t=0 is applied. If the DCI schedules CDM group λ=1, then the TCI state Id index t=0 (or optionally t=1) is applied. If the DCI schedules CDM group λ=2, then the TCI state Id index t=1 is applied. Similarly, in some cases, with respect to the FDM scheme, the scheduled CDM group determines which TCI state Id index is applied to which frequency portion.

[0458] In some cases, such as when "TDM Scheme B" is enabled (for example, when the UE is configured by the upper layer parameter PDSCH-config, and the upper layer parameter PDSCH-config indicates in PDSCH-TimeDomainResourceAllocation that at least one entry in the pdsch-TimeDomainAllocationList contains RepNumR16), the following scheme can be used. The UE can be further configured to enable cyclic or sequential TCI state mapping (for example, by CycMapping or SeqMapping in RepTCIMapping). If T=1, the same single TCI state (for example, t=0) is applied to each repetition. If T=2 and cyclic mapping is enabled, and the DM-RS antenna ports indicated in the DCI are within a CDM group, the first and second TCI states (for example, t=0 and t=1) are applied to the first and second PDSCH transmission opportunities, respectively, and the same TCI mapping pattern continues in the remaining PDSCH transmission opportunities.

[0459] If T=2 and sequential mapping is enabled, and the DM-RS antenna ports indicated in the DCI are within a CDM group, the first TCI state (e.g., t=0) is applied to the first and second PDSCH transmissions, and the second TCI state (e.g., t=1) is applied to the third and fourth PDSCH transmissions, and the same TCI mapping pattern continues in the remaining PDSCH transmission opportunities.

[0460] If T=2, and the DM-RS antenna ports indicated in the DCI are within two CDM groups, the first and second TCI states (e.g., t=0 and t=1) are applied to the two CDM groups in each repetition. In some cases, the same TCI state is applied to the same CDM group in each repetition, for example, t=0 is applied to the CDM group with the lowest index λ, and t=1 is applied to the other CDM group. In some cases, the mapping between TCI states and CDM groups is reversed in each repetition, for example, a TCI state with an Id index mod(r,T) is applied to the first CDM group, and a TCI state with an Id index mod(r+1,T) is applied to the second CDM group, where r=0, 1, ... is the index of the PDSCH transmission opportunity.

[0461] When the UE is configured with an FDM repetition scheme (eg, by setting the upper layer parameter RepSchemeEnabler to one of "FDMSchemeA" or "FDMSchemeB"), the following scheme may be applied if the DM-RS antenna ports indicated in the DCI are within one CDM group.

[0462] In some cases, such as when the UE is configured for "FDMSchemeA", if T=2, the UE will receive a single PDSCH transmission opportunity of the transport block in a first TCI state associated with a first frequency domain resource allocation (e.g., t=0) and a second TCI state associated with a second frequency domain resource allocation that does not overlap with the first frequency domain resource allocation (e.g., t=1).

[0463] In some cases, such as when the UE is configured for "FDMSchemeB", if T=2, the UE will receive two PDSCH transmission opportunities for the same TB in a first TCI state (e.g., t=0) associated with a PDSCH transmission opportunity with a first frequency domain resource allocation, and in a second TCI state (e.g., t=1) associated with a PDSCH transmission opportunity with a second frequency domain resource allocation that does not overlap with the first frequency domain resource allocation.

[0464] Example UE Procedure

[0465] An example UE procedure is as follows.

[0466] 1. The UE successfully decodes DCI on one or more received PDCCH candidates.

[0467] a. DCI schedules PDSCH.

[0468] b. If DCI is received on a PDCCH candidate associated with multiple activated TCI states, these activated TCI states include T TCI states.

[0469] 2. If the time offset between DCI reception (e.g., based on PDCCH reference resources) and the corresponding PDSCH is less than a threshold, the UE determines T TCI states as TCI states / QCL assumptions associated with the monitored PDCCH resources in the latest timeslot with monitored PDCCH resources in the active BWP. In addition:

[0470] a. If there are multiple such monitored PDCCH resources, the UE selects the monitored PDCCH resource with the lowest CORESET Id (in order to determine T TCI states).

[0471] b. If the UE is configured with two different values ​​of CORESETPoolIndex for a CORESET in the BWP, the UE selects a monitored PDCCH resource whose CORESETPoolIndex is the same as the PDCCH resource on which the DCI was received in the latest slot (in order to determine the T TCI states), wherein the latest slot has a monitored PDCCH resource whose CORESETPoolIndex is the same as the PDCCH resource on which the DCI was received. If the DCI is received in a repetition set with PDCCH candidates associated with two values ​​of CORESETPoolIndex, the UE may select two monitored PDCCH resources in the latest slot(s) including monitored PDCCH resources associated with different CORESETPoolIndex values ​​(in order to determine the T TCI states). For example, if the last slot includes the latest monitored PDCCH resource with CORESETPoolIndex=0, and the second to last slot includes the latest monitored PDCCH resource with CORESETPoolIndex=1, the UE may use the combined TCI state associated with these two monitored PDCCH resources as the T TCI states applied to PDSCH reception.

[0472] 3. If the time offset between the DCI reception (e.g., reference resource) and the corresponding PDSCH is equal to or greater than the threshold, and

[0473] a. If the DCI lacks the TCI field:

[0474] i. If the DCI is received on a PDCCH candidate belonging to a repetition set, eg, as described above, the repetition set includes PDCCH candidates associated with T different TCI states.

[0475] ii. If the DCI is received on a PDCCH candidate associated with multiple activated TCI states, then these activated TCI states include T TCI states.

[0476] b. If the DCI includes a TCI field, the UE follows the TCI field indication.

[0477] 4. Step 3 is about determining the TCI state that is subsequently used for reception in step 4. The UE receives the PDSCH using the previously determined T TCI states based on the UE configuration and DCI content (such as antenna port). In the case of fewer than T indicated CDM groups, selecting from the T TCI states can follow the various examples discussed above.

[0478] Default beam for PUSCH

[0479] As mentioned above, multi-TCI DCI and single-TCI DCI are considered.

[0480] In some cases, for example, for PUSCH scheduled via DCI format 0_0 on a cell, if the upper layer parameter enableDefaultBeamPlForPUSCH0_0 is set to "enabled", the UE is not configured with PUCCH resources on the active UL BWP, and the UE is in RRC connected mode, the UE shall send PUSCH with reference to the RS with "QCL-Type-D" (e.g., DL RS) corresponding to the QCL hypothesis of the CORESET with the lowest ID, according to the spatial relationship (if applicable).

[0481] In some cases, for example, for PUSCH scheduled via DCI format 0_0 on a cell, if the upper layer parameter enableDefaultBeamPlForPUSCH0_0 is set to "enabled", the UE is configured with PUCCH resources on the active UL BWP, where all PUCCH resources are not configured with any spatial relationship, and the UE is in RRC connected mode, the UE shall send PUSCH according to the spatial relationship (if applicable) with reference to the RS with "QCL-Type-D" corresponding to the QCL hypothesis of the CORESET with the lowest ID when the CORESET is configured on the CC.

[0482] Sending PUSCH in a spatial relationship with reference to a DL RS with "QCL-Type-D" may mean that the UE determines its PUSCH transmission precoder (or spatial transmission filter) partially (e.g., in combination with precoder information and the number of layers in the DCI) or completely based on the spatial filter used to receive the DL RS (e.g., UE RX beam).

[0483] In some cases, for example, for PUSCH scheduled via DCI format 0_0 on a cell, if the upper layer parameter enableDefaultBeamPlForPUSCH0_0 is set to "enabled", the UE is not configured with PUCCH resources on the active UL BWP, and the UE is in RRC connected mode, the UE shall send PUSCH according to the activated TCI state (e.g., UL TCI state) of the PUSCH (if applicable), with reference to the RS with "QCL-Type-D" (e.g., DL RS) corresponding to the QCL hypothesis of the CORESET with the lowest ID.

[0484] In some cases, for example, for PUSCH scheduled with DCI format 0_0 on a cell, if the upper layer parameter enableDefaultBeamPlForPUSCH0_0 is set to "enabled", the UE is configured with PUCCH resources on the active UL BWP, where all PUCCH resources are not configured with any TCI state (or no TCI state is activated), and the UE is in RRC connected mode, the UE shall send PUSCH according to the TCI state (if applicable) with reference to the RS with "QCL-Type-D" corresponding to the QCL assumption of the CORESET with the lowest ID when the CORESET is configured on the CC.

[0485] Sending PUSCH in an activated TCI state with reference to a DL RS with "QCL-Type-D" may mean that the UE determines its PUSCH transmission precoder (or spatial transmission filter) partially or completely based on the spatial filter (e.g., UE RX beam) used to receive the DL RS.

[0486] Note that in this document, the TCI state, spatial relationship or QCL of a PUSCH may refer to the TCI state or QCL of a DM-RS of the PUSCH. The PUSCH may be in the same or different BWP or cell as the corresponding PDCCH or CORESET / PDCCH resources considered below.

[0487] The above example illustrates a case where one or more activated TCI states of a CORESET are used to determine the precoder or spatial transmission filter for PUSCH transmission. For example, if the scheduling DCI is a multi-TCI DCI, the TCI state associated with the reception of the scheduling DCI can be used as the spatial relationship / TCI state / QCL assumption for the corresponding scheduled PUSCH.

[0488] In some cases, for example, if the UE is configured with two different values ​​of CORESETPoolIndex for a CORESET in the BWP, the spatial relation / TCI state / QCL assumption that the UE may use for the PUSCH may depend on in which CORESET the PDCCH scheduling the PUSCH was received. The UE may use the TCI state / QCL assumption for the CORESET on which the scheduling DCI was received. If the scheduling DCI is a multi-TCI DCI, the TCI state associated with the reception of the scheduling DCI may be used as the spatial relation / TCI state / QCL assumption for the corresponding scheduled PUSCH.

[0489] In the above various cases, multiple TCI states (eg, two) associated with the DCI scheduling the PUSCH may be used as the spatial relationship / TCI state / QCL assumptions for the scheduled PUSCH. This brings about various problems to be addressed below.

[0490] TCI state mapping to PUSCH DM-RS antenna port

[0491] One or more TCI states for the scheduled PUSCH are ordered and indexed as t=0,…,(T-1), where t is the TCI state ID index (not TCI state Id) and T is the number of activated TCI state IDs, e.g., based on the TCI state associated with the scheduling DCI or CORESET (e.g., the CORESET with the lowest Id) (see above).

[0492] Note that for brevity, the term "TCI state" of PUSCH is used below, however, it can correspond to "spatial relationship" if "spatial relationship" is used to describe the spatial transmission filter or transmit beam used for PUSCH transmission.

[0493] For example, as described above, the activated TCI state IDs of the CORESET may be sorted according to the sequential position or index in the MAC CE, or the sequential position of the corresponding MAC CE (first TCI state ID, second TCI state ID, etc.).

[0494] In some cases, the multi-TCI DCI for scheduling PUSCH is carried by one or more PDCCHs in a repetition set, where the PDCCH candidates in the repetition set are associated with different TCI states. These TCI states can also be sorted and indexed, for example, in the order of time and frequency of the corresponding PDCCH resources, or in the order of the corresponding CORESET Id.

[0495] Note that the DCI may schedule PUSCH repeatedly, for example based on a similar repetition scheme described for PDSCH, such as “FDMSchemeA”, “FDMSchemeB”, “TDMSchemeA” (intra-slot repetition), “TDM scheme B” (inter-slot repetition), or “SDM scheme” (see above).

[0496] Also note that the DCI may indicate a set of DM-RS antenna ports to be used for transmitting the PUSCH via the DCI field "antenna port". Different antenna ports may be associated with different code division multiplexing (CDM) groups. Thus, an indication of a set of DM-RS antenna ports may also, for example, implicitly indicate a set of CDM groups. Using a single spatial relationship / TCI state for all antenna ports belonging to the same CDM group may be beneficial to communication performance. CDM groups may be indexed as λ=0, 1, ...

[0497] In some cases, one of T TCI states is used to send the scheduled PUSCH, such as the first TCI state (t=0), for example, the same TCI state is applied to all scheduled antenna ports and CDM groups.

[0498] In some cases, if the number of scheduled CDM groups is one, the scheduled PUSCH is sent using one of T TCI states, such as the first TCI state (t=0), for example, the same TCI state is applied to all scheduled antenna ports within a single CDM group.

[0499] In some cases, for example, when T>1, if the number of scheduled CDM groups is two, two of the T TCI states are used to send the scheduled PUSCH, for example, the first TCI state (t=0) is applied to all antenna ports within the first scheduled CDM group (e.g., with the lowest CDM group index λ), and the second TCI state (t=1) is applied to all antenna ports within the second scheduled CDM group.

[0500] In some cases, the one or more antenna ports belonging to each scheduled CDM group λ are indicated by the scheduling DCI. In some cases, when transmitting PUSCH, the TCI state with Id index mod(λ+k,T) applies to CDM group λ, where mod(a,b) is an "a mod b" operation. In some cases, k=0, e.g., Id index is mod(λ,T). In some cases, k is the redundancy version used in the PUSCH transmission, e.g., as indicated by the DCI field "Redundancy Version".

[0501] In some cases, T TCI states are applied to the scheduled CDM groups such that the first TCI state Id index is assigned to the scheduled CDM group with the lowest index, etc., and the highest TCI state Id index is assigned to the scheduled CDM group with the highest index. For example, when T=2, t=0 is assigned to CDM groups 0 and 1, and t=1 is assigned to CDM group 2. In another example, t=0 is assigned to CDM group 0, and t=1 is assigned to CDM groups 1 and 2.

[0502] In some cases where the PUSCH repetition scheme is configured or indicated by DCI, e.g., as per one of the examples herein, the same TCI state is used in each repetition.

[0503] In some cases, such as when "TDMSchemeA" is enabled (e.g., the UE is configured by the upper layer parameter RepSchemeEnabler set to "TDMSchemeA"), the number of PUSCH transmission opportunities is derived from T. If T = 1, a single PUSCH transmission opportunity is used, and a single TCI state (e.g., t = 0) applies to PUSCH transmission. If T = 2, two PUSCH transmission opportunities are used, and the first TCI state (e.g., t = 0) applies to the first PUSCH opportunity, and the second TCI state (e.g., t = 1) applies to the second PUSCH opportunity.

[0504] In some cases, the scheduled CDM group λ determines the TCI state. For example, if the DCI schedules CDM group λ=0, then the TCI state Id index t=0 is applied. If the DCI schedules CDM group λ=1, then the TCI state Id index t=0 (or optionally t=1) is applied. If the DCI schedules CDM group λ=2, then the TCI state Id index t=1 is applied. Similarly, in some cases, with respect to the FDM scheme, the scheduled CDM group determines which TCI state Id index is applied to which frequency portion.

[0505] In some cases, such as when "TDM Scheme B" is enabled (e.g., when the UE is configured by the upper layer parameter PUSCH-config, the upper layer parameter PUSCH-config indicates in PUSCH-TimeDomainResourceAllocation that at least one entry in pusch-TimeDomainAllocationList contains RepNumR17), the following scheme may be used. The UE may be further configured to enable cyclic or sequential TCI state mapping (e.g., by CycMapping or SeqMapping in RepTCIMapping).

[0506] • If T=1, the same single TCI state (eg, t=0) is applied to each repetition.

[0507] If T=2 and cyclic mapping is enabled, and the DM-RS antenna ports indicated in the DCI are within one CDM group, the first and second TCI states (e.g., t=0 and t=1) are applied to the first and second PUSCH transmission opportunities, respectively, and the same TCI mapping pattern continues in the remaining PUSCH transmission opportunities.

[0508] If T=2 and sequential mapping is enabled, and the DM-RS antenna ports indicated in the DCI are within one CDM group, the first TCI state (e.g., t=0) is applied to the first and second PUSCH transmissions, and the second TCI state (e.g., t=1) is applied to the third and fourth PUSCH transmissions, and the same TCI mapping pattern continues in the remaining PUSCH transmission opportunities.

[0509] If T=2, and the DM-RS antenna ports indicated in the DCI are within two CDM groups, the first and second TCI states (e.g., t=0 and t=1) are applied to the two CDM groups in each repetition. In some cases, the same TCI state is applied to the same CDM group in each repetition, for example, t=0 is applied to the CDM group with the lowest index λ, and t=1 is applied to the other CDM group. In some cases, the mapping between TCI states and CDM groups is reversed in each repetition, for example, the TCI state with Id index mod(r,T) is applied to the first CDM group, and the TCI state with Id index mod(r+1,T) is applied to the second CDM group, where r=0, 1, ... is the index of the PUSCH transmission opportunity.

[0510] When the UE is configured with an FDM repetition scheme (eg, by setting the upper layer parameter RepSchemeEnabler to one of "FDMSchemeA" or "FDMSchemeB"), the following scheme may be applied if the DM-RS antenna ports indicated in the DCI are within one CDM group.

[0511] In some cases, such as when the UE is configured for "FDMSchemeA", if T=2, the UE shall send a single PUSCH transmission opportunity of a transport block in a first TCI state associated to a first frequency domain resource allocation (e.g., t=0) and a second TCI state associated to a second frequency domain resource allocation that does not overlap with the first frequency domain resource allocation (e.g., t=1).

[0512] In some cases, such as when the UE is configured for "FDMSchemeB", if T=2, the UE shall send two PUSCH transmission opportunities for the same TB in a first TCI state (e.g., t=0) associated with a PUSCH transmission opportunity with a first frequency domain resource allocation, and in a second TCI state (e.g., t=1) associated with a PUSCH transmission opportunity with a second frequency domain resource allocation that does not overlap with the first frequency domain resource allocation.

[0513] Example UE Procedure

[0514] An example UE procedure is as follows.

[0515] 1. The UE successfully decodes DCI on one or more received PDCCH candidates.

[0516] a. DCI schedules PUSCH.

[0517] b. If DCI is received on a PDCCH candidate associated with multiple activated TCI states, these activated TCI states include T TCI states.

[0518] 2. If some conditions hold, eg, the UE is so configured, the UE determines the T TCI states as, eg, the TCI states / QCL assumptions associated with the decoded DCI or associated with the CORESET (eg, with the lowest Id).

[0519] 3. The UE uses the previously determined T TCI states and based on the UE configuration and DCI content (such as antenna port), sends PUSCH. In the case of less than T indicated CDM groups, selecting from the T TCI states can follow the various examples discussed above.

[0520] Default beam for PUCCH

[0521] introduction

[0522] As mentioned above, multi-TCI DCI and single-TCI DCI are considered.

[0523] In some cases, for example, if the UE

[0524] -report beamCorrespondenceWithoutUL-BeamSweeping,

[0525] -pathlossReferenceRS is not provided in PUCCH-PowerControl,

[0526] -enableDefaultBeamPlForPUCCH is provided, and

[0527] -PUCCH-SpatialRelationInfo is not provided,

[0528] The spatial setting for PUCCH transmission from the UE is then the same as the spatial setting for PDCCH reception by the UE in the CORESET with the lowest ID on the active DL BWP of the cell (e.g., PCell, PSCellL or PUCCH SCell).

[0529] Sending PUCCH with the same spatial relationship as the spatial setting with respect to PDCCH reception of UEs in the CORESET may mean that the UE determines its PUCCH transmit precoder (or spatial transmit filter) based partially or entirely on the spatial filter (e.g., UE RX beam) used to receive PDCCH.

[0530] Note that in this document, the TCI state, spatial relationship or QCL of a PUCCH may refer to the TCI state or QCL of a DM-RS of the PUCCH. The PUUCH may be in the same or different BWP or cell as the corresponding PDCCH or CORESET / PDCCH resources considered below.

[0531] The above examples illustrate the case where one or more activated TCI states of a CORESET are used to determine the precoder or spatial transmission filter for PUCCH transmission.

[0532] In the various cases described above, multiple TCI states (e.g., two) associated with the CORESET (e.g., with the lowest ID on the active DL BWP) may be used as the spatial relationship / TCI state / QCL assumptions for PUCCH transmissions. This brings up various issues that are addressed below.

[0533] TCI status mapping to PUCCH

[0534] One or more TCI states for PUCCH are ordered and indexed as t=0,…,(T-1), where t is the TCI state ID index (not TCI state Id) and T is the number of activated TCI state IDs, e.g. based on the TCI state associated with the scheduling DCI or CORESET (e.g., the CORESET with the lowest Id) (see above).

[0535] Note that for brevity, the term "TCI state" of PUUCH is used below, however, it can correspond to "spatial relationship" if "spatial relationship" is used to describe the spatial transmission filter or transmit beam used for PUUCH transmission.

[0536] For example, as described above, the activated TCI state IDs of the CORESET may be sorted according to the sequential position or index in the MAC CE, or the sequential position of the corresponding MAC CE (first TCI state ID, second TCI state ID, etc.).

[0537] In some cases, multi-TCI DCI is carried by one or more PDCCHs in a repetition set, where the PDCCH candidates in the repetition set are associated with different TCI states. These TCI states can also be sorted and indexed, for example, in order of time and frequency of the corresponding PDCCH resources, or in order of the corresponding CORESET Id. This may be applicable, for example, in the case where a PUCCH transmission follows a DCI reception (e.g., HARQ-ACK (for a scheduled PDSCH) carried on the PUCCH).

[0538] In some cases, one of T TCI states is used to transmit the PUCCH, such as the first TCI state (t=0), eg, the same TCI state is applied to all scheduled antenna ports and CDM groups.

[0539] In some cases where the PUCCH repetition scheme is configured or indicated by DCI, e.g., as per one of the examples herein, the same TCI state is used in each repetition.

[0540] In some cases, the number of PUCCH transmission opportunities is derived from T:

[0541] • If T=1, a single PUCCH transmission opportunity is used, and a single TCI state (eg, t=0) applies to PUCCH transmission.

[0542] If T=2, two PUCCH transmission opportunities are used, and the first TCI state (eg, t=0) is applicable to the first PUCCH opportunity, and the second TCI state (eg, t=1) is applicable to the second PUCCH opportunity.

[0543] In some cases, the following scheme may be used: The UE may be further configured to enable cyclic or sequential TCI state mapping (eg, via CycMapping or SeqMapping in RepTCIMapping).

[0544] • If T=1, the same single TCI state (eg, t=0) is applied to each repetition.

[0545] If T=2 and cyclic mapping is enabled, the first and second TCI states (eg, t=0 and t=1) are applied to the first and second PUCCH transmission opportunities, respectively, and the same TCI mapping pattern continues in the remaining PUCCH transmission opportunities.

[0546] If T=2 and sequential mapping is enabled, the first TCI state (e.g., t=0) is applied to the first and second PUCCH transmissions, while the second TCI state (e.g., t=1) is applied to the third and fourth PUCCH transmissions, and the same TCI mapping pattern continues in the remaining PUCCH transmission opportunities.

[0547] When the UE is configured with an FDM repetition scheme (eg, by setting the upper layer parameter RepSchemeEnabler to one of "FDMSchemeA" or "FDMSchemeB"), the following scheme may be applied if the DM-RS antenna ports indicated in the DCI are within one CDM group.

[0548] In some cases, such as when the UE is configured for "FDMSchemeA", if T=2, the UE shall send a single PUCCH transmission opportunity in a first TCI state associated with a first frequency domain resource allocation (e.g., t=0) and a second TCI state associated with a second frequency domain resource allocation that does not overlap with the first frequency domain resource allocation (e.g., t=1).

[0549] In some cases, such as when the UE is configured for "FDMSchemeB", if T=2, the UE shall send two PUCCH transmission opportunities in a first TCI state (e.g., t=0) associated with a first PUCCH transmission opportunity with a first frequency-domain resource allocation, and in a second TCI state (e.g., t=1) associated with a second PUCCH transmission opportunity with a second frequency-domain resource allocation that does not overlap with respect to the first frequency-domain resource allocation.

[0550] Default beam for aperiodic CSI-RS

[0551] In various cases, one or more non-periodic CSI-RS resources may be triggered by DCI carried by one or more PDCCHs (e.g., multi-TCI DCI or single-TCI DCI as discussed above). The triggering PDCCH and CSI-RS may have the same or different parameter sets, such as subcarrier spacing, cyclic prefix, etc.

[0552] The CSI-RS resources may be associated with a QCL configuration, for example, a TCI state indicated by an RRC configuration.

[0553] If the time offset (scheduling offset) between the last symbol of the PDCCH carrying the DCI (e.g., the PDCCH on the reference PDCCH resource) and the first symbol of the triggered aperiodic CSI-RS resource is greater than a threshold, the UE can be expected to apply the QCL assumption in the TCI state for the triggered aperiodic CSI-RS resource.

[0554] The threshold may be based on a value reported by the UE, such as UE capabilities, e.g., parameter beamSwitchTiming or beamSwitchTiming-rL6. In some cases, additional conditions other than the timing offset may apply as above. In the example, the threshold is one of the values ​​of {14,28,48}[symbols], while another parameter such as enableBeamSwitchTiming is not provided to the UE, and the CSI-RS resource set is not configured with another upper layer parameter, such as trs-Info.

[0555] In the example, the threshold is one of the values ​​of {14, 28, 48}, and the CSI-RS resource set is configured with an upper layer parameter, such as trs-Info.

[0556] In the example, a parameter such as enableBeamSwitchTiming is provided to the UE, and the CSI-RS resource set is configured with a higher layer parameter repetition set to "on".

[0557] In some cases, if the time offset is equal to or greater than 48 when the UE provides a parameter such as beamSwitchTiming-rl6, and another parameter such as enableBeamSwitchTiming is provided to the UE, and the CSI-RS resource set is configured with the upper layer parameter repetition set to "off", or is not configured with the upper layer parameters repetition and trs-Info, the UE can be expected to apply the QCL assumption in the TCI state for the triggered non-periodic CSI-RS resources.

[0558] In various other cases, the UE may apply the QCL assumption for the CORESET with the lowest controlResourceSetId and associated with the monitored search space in the latest slot in which one or more CORESETs within the active BWP of the serving cell are monitored. This may be applicable if one or more other conditions are met, such as at least one CORESET is configured for the BWP in which aperiodic CSI-RS is received, or if no parameters such as enableTwoDefaultTCIStates are configured.

[0559] If the CORESET has more than one activated TCI state, the UE may, for example, apply the QCL assumption in the first or these activated TCI states, where the TCI state order (e.g., first, second) may, for example, be based on the ordinal position in the MAC CE for the CORESET TCI state activation. In another example, the UE may apply a QCL assumption derived from one of these activated TCI states (e.g., the TCI state with the lowest or highest TCI state ID) based on the TCI state ID.

[0560] In some cases, for example, if the UE is configured with RRC parameters that enable such behavior (e.g., enableTwoDefaultTCIStates), the UE may apply QCL assumptions derived from more than one activated TCI state to all or a subset of the triggered CSI-RS resources. In one example, a first TCI state is applied to a first subset of CSI-RS resources, and a second TCI state is applied to a second subset of CSI-RS resources. The first and second subsets may correspond to different groups of symbols, for example, the UE applies different QCL assumptions in different non-intersecting groups of symbols that include CSI-RS resources. In some cases, multiple (e.g., two) TCI states are applied to the same symbol carrying CSI-RS resources. In some cases, the first and second TCI states are applied to CSI-RS resources in the same one or more symbols, but the first TCI state is applied to a first code division multiplexing (CDM) group, and the second TCI state is applied to a second CDM group.

[0561] In some cases, the UE may apply QCL assumptions of more than one activated TCI state from one or more CORESETs carrying the PDCCH (multi-TCI DCI) that triggers the aperiodic CSI-RS resources to the triggered CSI-RS resources. In one example, this is also done if the time offset is greater than or equal to a threshold.

[0562] Definitions and Abbreviations

[0563] Table 15 below shows a list of acronyms that may appear in the above description. Unless otherwise stated, acronyms used herein refer to the corresponding terms listed below.

[0564] Table 15

[0565]

[0566]

[0567]

[0568]

[0569] It should be understood that, for example, Figure 3 , Figure 6A-Figure 8 or Fig.15 The entities of the illustrated steps can be logical entities. The individual steps can be stored in a file such as Figure 1F or Figure 1G In the memory of a device, server or computer system such as shown in the diagram, and executed on its processor. It is contemplated that in this document (for example, Figure 3 , Figure 6A-Figure 8 or Fig.15 ) to skip steps, merge steps, or add steps between the exemplary methods disclosed.

[0570] In describing preferred methods, systems, or devices for the subject matter of the present disclosure as illustrated in the figures - transport mode switching for multicast and broadcast services in networks such as 5G - specific terminology is employed for the sake of clarity. However, the claimed subject matter is not intended to be limited to the specific terminology so selected.

[0571] The various techniques described herein can be implemented in combination with hardware, firmware, software or, when appropriate, in combination with their combination. Such hardware, firmware and software can reside in the equipment of each node located in the communication network. The equipment can operate individually or in combination with each other to implement the methods described herein. The terms "equipment", "network equipment", "node", "device", "network node" etc. used herein can be used interchangeably. In addition, unless otherwise specified herein, the use of the word "or" is usually used inclusively.

[0572] This written description uses examples of the disclosed subject matter, including the best mode, and also enables any person skilled in the art to practice the disclosed subject matter, including making and using any devices or systems and performing any included methods. The disclosed subject matter may include other examples that occur to those skilled in the art (e.g., skipping steps, merging steps, or adding steps between the exemplary methods disclosed herein).

[0573] Methods, systems, devices, etc. described herein may provide for sending PDCCH transmissions to user devices via multiple transmission mediums. The multiple transmission mediums may be at least one of transmissions from multiple transmission / reception points (TRPs), multi-beam transmissions, or repeated transmissions of PDCCH transmissions. The PDCCH may be sent on multiple control resource sets (CORESETs), wherein each of the multiple CORESETs is associated with a transmission control indicator (TCI) state. The PDCCH may be sent on a single control resource set (CORESET), and the single CORESET is associated with multiple transmission control indicator (TCI) states. Methods, systems, devices, etc. described herein may provide for determining a repetition set; decoding one or more repetitions of downlink control information (DCI) associated with a repetition set; determining that there is a first UE action indicated by the DCI that may be prior to the reception of the PDCCH; and selecting one or more reference resources based on the determination that there is a first UE action indicated by the DCI that is prior to the reception of the PDCCH. The UE may perform the action based on the timing of the reference resource. The selection may be more than one reference resource based on the determination that there may be at least a second UE action indicated by the DCI that is subsequent to the reception of the PDCCH. The DCI may be associated with PDCCH reception of multiple transmission configuration indicator (TCI) states. The DCI may be carried by one or more PDCCHs in a repetition set. When a quasi co-location (QCL) with respect to a spatial Rx parameter is configured for at least one transmission configuration indicator (TCI) state in the considered serving cell, the QCL of the PDSCH is determined, wherein the QCL may depend on the time offset between the reception of the DCI and the corresponding scheduled PDSCH. When a quasi co-location (QCL) with respect to a spatial Rx parameter may be configured for at least one transmission configuration indicator (TCI) state in the considered serving cell, the TCI state is determined, wherein the TCI state may depend on the time offset between the reception of the DCI and the corresponding scheduled PDSCH. When the time offset may be equal to or greater than a threshold, a first predetermined indication of a transmission configuration indicator (TCI) state or quasi co-location (QCL) for the PDSCH is used. All combinations (including deletion or addition of steps) in this paragraph and the next paragraph may be conceived in a manner consistent with other parts of the specific implementation.

[0574] The methods, systems, devices, etc. described herein may provide for determining a repetition set containing multiple PDCCH candidates; receiving one or more PDCCH candidates associated with the repetition set; decoding one or more repetitions of downlink control information (DCI) associated with the repetition set from the one or more PDCCH candidates; determining that there is a first UE action indicated by the DCI before the reception of the PDCCH; and selecting one or more reference resources based on the determination that there is a first UE action indicated by the DCI before the reception of the PDCCH. The methods, systems, devices, etc. described herein may provide for performing the first UE action by using a reference resource as a time reference for the UE action. One or more PDCCH candidates in the repetition set are associated with different TCI states. The methods, systems, devices, etc. described herein may provide for determining a repetition set containing multiple PDCCH candidates; determining that there is a first UE action indicated by the DCI; selecting one or more reference resources based on the determination that there is a first UE action indicated by the DCI; encoding downlink control information (DCI) based on the selection of the one or more reference resources; and sending the DCI on one or more PDCCH candidates associated with the repetition set. The device may be a network device. All combinations of this and the previous paragraph (including deletion or addition of steps) may be contemplated in a manner consistent with the rest of the detailed description.

Claims

1. A method of a user equipment (UE) for improving reliability of a physical downlink control channel (PDCCH) in a communication network, the method comprising: Determine a set of multiple PDCCH candidates, the set being referred to as a repetition set; receiving one or more PDCCH candidates of a repetition set; decoding downlink control information (DCI) from the received one or more PDCCH candidates; Determining that there is a first action indicated by the DCI, the first action being for the UE; selecting a first reference resource in the repetition set based on determining that there is a first action indicated by the DCI; as well as The first action is performed by using the first reference resource as a time reference for the first action.

2. The method according to claim 1, further comprising: Determining that there is a second action indicated by the DCI, the second action being for the UE; selecting a second reference resource in the repetition set based on determining that there is a second action indicated by the DCI; as well as performing the second action by using the second reference resource as a time reference for the second action, The second action is after receiving the PDCCH candidate.

3. The method of claim 1, wherein reception of one or more PDCCH candidates is based on different transmission configuration indicator (TCI) states.

4. The method of claim 1, wherein the first action is a scheduled physical downlink shared channel (PDSCH), wherein the method further comprises: When a quasi co-location (QCL) with respect to a spatial reception (Rx) parameter is configured for at least one transmission configuration indicator (TCI) state in the considered serving cell, a QCL of the PDSCH is determined, wherein the QCL depends on a time offset indicated in the DCI, which is a time offset between reception of the DCI and the corresponding scheduled PDSCH.

5. The method of claim 1, wherein the first action is a scheduled physical downlink shared channel (PDSCH), wherein the method further comprises: When quasi co-location (QCL) relative to a spatial reception (Rx) parameter is configured for at least one transmission configuration indicator (TCI) state in a considered serving cell, the at least one transmission configuration indicator (TCI) state is determined, wherein the at least one transmission configuration indicator (TCI) state depends on a time offset indicated in a DCI, the time offset being a time offset between reception of the DCI and a corresponding scheduled PDSCH.

6. The method according to claim 4 or 5, further comprising: It is determined whether the time offset is equal to or greater than a threshold, and the at least one transmission configuration indicator (TCI) state of the PDSCH or the first predetermined indication of the quasi co-location (QCL) is used.

7. A user equipment (UE) for improving reliability of a physical downlink control channel (PDCCH) in a communication network, the UE comprising: processor; as well as A memory coupled to the processor, the memory storing executable instructions, which, when executed by the processor, causes the processor to implement operations including: Determine a set of multiple PDCCH candidates, the set being referred to as a repetition set; receiving one or more PDCCH candidates of a repetition set; decoding downlink control information (DCI) from the received one or more PDCCH candidates; Determining that there is a first action indicated by the DCI, the first action being for the UE; selecting a first reference resource in the repetition set based on determining that there is a first action indicated by the DCI; as well as The first action is performed by using the first reference resource as a time reference for the first action.

8. The UE according to claim 7, wherein the operations further comprise: Determining that there is a second action indicated by the DCI, the second action being for the UE; selecting a second reference resource in the repetition set based on determining that there is a second action indicated by the DCI; as well as performing the second action by using the second reference resource as a time reference for the second action, The second action is after receiving the PDCCH candidate.

9. The UE of claim 7, wherein reception of one or more PDCCH candidates is based on different transmission configuration indicator (TCI) states.

10. The UE of claim 7, wherein the first action is a scheduled physical downlink shared channel (PDSCH), wherein the operations further comprise: When a quasi co-location (QCL) with respect to a spatial reception (Rx) parameter is configured for at least one transmission configuration indicator (TCI) state in the considered serving cell, a QCL of the PDSCH is determined, wherein the QCL depends on a time offset indicated in the DCI, which is a time offset between reception of the DCI and the corresponding scheduled PDSCH.

11. The UE of claim 7, wherein the first action is a scheduled physical downlink shared channel (PDSCH), wherein the operations further comprise: When quasi co-location (QCL) relative to a spatial reception (Rx) parameter is configured for at least one transmission configuration indicator (TCI) state in a considered serving cell, the at least one transmission configuration indicator (TCI) state is determined, wherein the at least one transmission configuration indicator (TCI) state depends on a time offset indicated in a DCI, the time offset being a time offset between reception of the DCI and a corresponding scheduled PDSCH.

12. A network device, comprising: processor; as well as A memory coupled to the processor, the memory storing executable instructions, which, when executed by the processor, causes the processor to implement operations including: determining a set of multiple physical downlink control channel (PDCCH) candidates, the set being referred to as a repetition set; determining that there is a first action indicated by downlink control information (DCI) for a first user equipment (UE); selecting one or more reference resources based on determining that there is a first action indicated by the DCI; encoding the DCI based on the selection of the one or more reference resources; as well as The encoded DCI is sent on the PDCCH candidate of the repetition set.

13. The network device of claim 12, wherein the first action is a scheduled physical downlink shared channel (PDSCH), wherein the operations further comprise: When a quasi co-location (QCL) with respect to a spatial reception (Rx) parameter is configured for at least one transmission configuration indicator (TCI) state in the considered serving cell, a QCL of a PDSCH is determined, wherein the QCL depends on a time offset indicated in the DCI, the time offset being a time offset between reception of the DCI and a corresponding scheduled PDSCH, or the at least one transmission configuration indicator (TCI) state is determined, wherein the at least one transmission configuration indicator (TCI) state depends on a time offset indicated in the DCI, the time offset being a time offset between reception of the DCI and a corresponding scheduled PDSCH.

14. The network device of claim 13, wherein the operations further comprise: It is determined whether the time offset is equal to or greater than a threshold, and the at least one transmission configuration indicator (TCI) state of the PDSCH or the first predetermined indication of the quasi co-location (QCL) is used.

15. The network device of claim 12, wherein the network device is a base station component.

Images