Method, architecture, apparatus, and system for enhanced system information acquisition in cell-free MIMO deployments

Abstract

Methods, architectures, apparatus, systems, devices, and computer program products related to enhanced system information (SI) message acquisition, particularly in cell-free multiple-input multiple-output (MIMO) deployments, are described. For example, a wireless transmit / receive unit (WTRU) is configured to: receive a synchronization signal block (SSB) based on a first physical cell identity (PCI); decode a payload of the SSB, the payload including information indicative of a resource set and a search space configuration; receive a system information block (SIB) based on the first PCI and the resource set and the search space configuration; determine information indicative of a second PCI based on the SIB; receive a scheduled transmission including system information based on the second PCI, the second PCI being different from the first PCI; and receive a scheduled transmission including the system information based on the second PCI, the scheduled transmission being quasi-co-located (QCL) with the SSB.

Description

[Technical Field]

[0001] The present disclosure is generally directed to the fields of communications, software, and encoding, including methods, architectures, apparatus, and systems relating to enhanced system information (SI) message acquisition, particularly in cell-free multiple-input multiple-output (MIMO) deployments, for example. [Background technology]

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Patent Application No. 63 / 434,195, filed December 21, 2022, which is incorporated herein by reference. Summary of the Invention

[0003] SI overhead reduction in legacy synchronization signal / physical broadcast channel (PBCH) block (SSB)-based cell-free MIMO deployments is provided. In 5G New Radio (NR), SI messages are transmitted per SSB and per physical cell ID (PCI), which can result in significant overhead in supercells.

[0004] An enhanced SI message acquisition is disclosed in which a WTRU (e.g., a UE) receives SI messages using an anchor PCI in the super-cell rather than the PCI of the detected SSB. Additionally, joint SI message transmission across multiple SSBs using PCI is disclosed.

[0005] A method and apparatus are provided for enhanced SI message acquisition. In one embodiment, the method includes an anchor PCI for SI message reception configured in SIB1. The anchor PCI may be different from the PCI of the detected SSB and the PCI used to receive SI block type 1 (SIB1). The method further includes receiving, by the WTRU (e.g., UE), the SI message using the anchor PCI. The method further includes an SSB group for SI message reception configured in SIB1. The detected SSB is in the SSB group. The method further includes, by the WTRU (e.g., UE), receiving the SI message on time-frequency resources associated with the SSBs in the SSB group. The WTRU (e.g., UE) may operate in (e.g., assume) a state in which the SI message is quasi-co-located (QCL) with the SSBs in the SSB group. [Brief explanation of the drawings]

[0006] A more detailed understanding can be had from the following detailed description, given by way of example in conjunction with the drawings attached hereto. The figures in such drawings, like the detailed description, are examples. Therefore, the figures and detailed description should not be considered limiting, as other equally valid examples are possible and may occur. Moreover, like reference numerals in the figures indicate like elements.

[0007] [Figure 1A] FIG. 1 is a system diagram illustrating an example communication system. [Figure 1B] 1B is a system diagram illustrating an example wireless transmit / receive unit (WTRU) that may be used within the communication system shown in FIG. 1A. [Figure 1C] 1B is a system diagram illustrating an example radio access network (RAN) and an example core network (CN) that may be used within the communication system shown in FIG. 1A. [Figure 1D] FIG. 1B is a system diagram illustrating a further exemplary RAN and a further exemplary CN that may be used within the communication system shown in FIG. 1A. [Figure 2] FIG. 1 illustrates a point in the context of a transmitting and receiving point(s) (TRP) and / or receiving point (RP). [Figure 3] FIG. 1 shows a cell with two TRPs and four SSBs. [Figure 4] FIG. 1 illustrates SSB and physical downlink control channel (PDCCH) / physical data shared channel (PDSCH) for SIB1 acquisition in 5G NR. [Figure 5] FIG. 1 illustrates enhanced SI capture in a supercell. [Figure 6] FIG. 1 is a system diagram illustrating a procedure for enhanced SI message capture. [Figure 7] FIG. 10 is a system diagram illustrating further procedures for enhanced SI message capture. [Figure 8] FIG. 10 illustrates a joint multi-TRP transmission of an SI message. [Figure 9] FIG. 10 illustrates a joint multi-TRP transmission of an SI message. [Figure 10] A diagram showing SI message transmission using SSB groups in a super cell with multiple PCIs. [Figure 11] FIG. 10 is a system diagram illustrating further procedures for enhanced SI message capture. [Figure 12] FIG. 10 illustrates a joint multi-TRP transmission of an SI message on a first occasion and a second occasion. [Figure 13] FIG. 1 illustrates enhanced SI capture in a supercell. [Figure 14] FIG. 10 is a system diagram illustrating further procedures for enhanced SI message capture. [Figure 15] FIG. 10 illustrates another method of enhanced SI message capture. [Figure 16] FIG. 10 illustrates another method of enhanced SI message capture. DETAILED DESCRIPTION OF THE INVENTION

[0008] In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments and / or examples disclosed herein. It will be understood, however, that such embodiments and examples may be practiced without some or all of the specific details set forth herein. In other instances, well-known methods, procedures, components, and circuits have not been described in detail so as not to obscure the following description. Furthermore, embodiments and examples not specifically described herein may be practiced in place of, or in combination with, embodiments and other examples explicitly, implicitly, and / or inherently described, disclosed, or otherwise provided (collectively, "provided") herein. Although various embodiments are described and / or claimed herein in which apparatuses, systems, devices, etc., and / or any elements thereof, perform operations, processes, algorithms, functions, etc., and / or any portions thereof, it should be understood that any embodiment described and / or claimed herein assumes that any apparatus, system, device, etc., and / or any elements thereof, are configured to perform any operation, process, algorithm, function, etc., and / or any portion thereof.

[0009] Exemplary Communication System

[0010] The methods, apparatus, and systems provided herein are suitable for communication involving both wired and wireless networks. An overview of various types of wireless devices and infrastructure is provided with respect to Figures 1A-1D, where various elements of the network may utilize, implement, be arranged in accordance with, and / or be adapted and / or configured for the methods, apparatus, and systems provided herein.

[0011] 1A is a system diagram illustrating an example communication system 100 in which one or more disclosed embodiments may be implemented. The communication system 100 may be a multiple-access system that provides content, such as voice, data, video, messaging, broadcast, etc., to multiple wireless users. The communication system 100 may enable the multiple wireless users to access such content through the sharing of system resources, including wireless bandwidth. For example, the communication system 100 may employ one or more channel access methods, such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), single-carrier FDMA (SC-FDMA), zero-tail (ZT) unique-word (UW) discrete Fourier transform (DFT) spread OFDM (ZT UW DTS-s OFDM), unique word OFDM (UW-OFDM), resource block filtered OFDM, filter bank multicarrier (FBMC), etc.

[0012] 1A, communications system 100 may include wireless transmit / receive units (WTRUs) 102a, 102b, 102c, 102d, radio access networks (RANs) 104 / 113, core networks (CNs) 106 / 115, public switched telephone networks (PSTNs) 108, the Internet 110, and other networks 112, although it will be appreciated that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, and / or network elements. Each of WTRUs 102a, 102b, 102c, 102d may be any type of device configured to operate and / or communicate in a wireless environment. By way of example, the WTRUs 102a, 102b, 102c, 102d, any of which may be referred to as a “station” and / or “STA,” may be configured to transmit and / or receive wireless signals, and may include (or be) user equipment (UE), a mobile station, a fixed or mobile subscriber unit, a subscription-based unit, a pager, a cellular phone, a personal digital assistant (PDA), a smartphone, a laptop, a netbook, a personal computer, a wireless sensor, a hotspot or Mi-Fi device, an Internet of Things (IoT) device, a watch or other wearable, a head-mounted display (HMD), a vehicle, a drone, a medical device and application (e.g., remote surgery), an industrial device and application (e.g., robots and / or other wireless devices operating in an industrial and / or automated processing chain context), a consumer electronics device, a device operating on a commercial and / or industrial wireless network, etc. Any of the WTRUs 102a, 102b, 102c, and 102d may be referred to interchangeably as a UE.

[0013] The communications system 100 may also include a base station 114a and / or a base station 114b. Each of the base stations 114a, 114b may be any type of device configured to wirelessly interface with at least one of the WTRUs 102a, 102b, 102c, 102d to facilitate access to one or more communications networks, such as, for example, the CN 106 / 115, the Internet 110, and / or the network 112. By way of example, the base stations 114a, 114b may be any of a base transceiver station (BTS), a Node B (NB), an eNode B (eNB), a Home Node B (HNB), a Home eNode B (HeNB), a gNode B (gNB), a NR Node B (NR NB), a site controller, an access point (AP), a wireless router, etc. Although the base stations 114a, 114b are each shown as a single element, it will be appreciated that the base stations 114a, 114b may include any number of interconnected base stations and / or network elements.

[0014] The base station 114a may be part of the RAN 104 / 113, which may also include other base stations and / or network elements (not shown), such as a base station controller (BSC), a radio network controller (RNC), relay nodes, etc. The base station 114a and / or base station 114b may be configured to transmit and / or receive wireless signals on one or more carrier frequencies, sometimes referred to as a cell (not shown). These frequencies may be licensed spectrum, unlicensed spectrum, or a combination of licensed and unlicensed spectrum. A cell may provide coverage for wireless services in a particular geographic area, which may be relatively fixed or may change over time. A 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 one embodiment, the base station 114a may include three transceivers, i.e., one for each sector of the cell. In one embodiment, the base station 114a may employ multiple-input multiple-output (MIMO) technology and utilize multiple transceivers for each or any sector of the cell. For example, beamforming may be used to transmit and / or receive signals in desired spatial directions.

[0015] The base stations 114a, 114b may communicate with one or more of the WTRUs 102a, 102b, 102c, 102d over an air interface 116, which may be any suitable wireless communication link (e.g., radio frequency (RF), microwave, centimeter wave, micrometer wave, infrared (IR), ultraviolet (UV), visible light, etc.). The air interface 116 may be established using any suitable radio access technology (RAT).

[0016] More particularly, as mentioned 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 and the WTRUs 102a, 102b, 102c in the RAN 104 / 113 may implement a radio technology such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which may establish the air interface 116 using Wideband CDMA (WCDMA). WCDMA may include communication protocols such as High Speed ​​Packet Access (HSPA) and / or Evolved HSPA (HSPA+). HSPA may include High Speed ​​Downlink Packet Access (HSDPA) and / or High Speed ​​Uplink Packet Access (HSUPA).

[0017] In one embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as Evolved UMTS Terrestrial Radio Access (E-UTRA), which may establish the air interface 116 using Long Term Evolution (LTE) and / or LTE Advanced (LTE-A) and / or LTE Advanced Pro (LTE-A Pro).

[0018] In one embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology, such as New Radio (NR) radio access, which may establish the air interface 116 using NR.

[0019] In one embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement multiple radio access technologies. For example, the base station 114a and the WTRUs 102a, 102b, 102c may jointly implement LTE radio access and NR radio access, e.g., using dual connectivity (DC) principles. Thus, the air interface utilized by the WTRUs 102a, 102b, 102c may be characterized by multiple types of radio access technologies and / or transmissions from / to multiple types of base stations (e.g., eNBs and gNBs).

[0020] In one embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a wireless technology such as IEEE 802.11 (i.e., Wireless Fidelity (Wi-Fi)), IEEE 802.16 (i.e., Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 1X, 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), or the like.

[0021] 1A may be, for example, a wireless router, a Home NodeB, a Home eNodeB, or an access point and may utilize any suitable RAT for facilitating wireless connectivity in a localized area, such as a business, a home, a vehicle, a campus, an industrial facility, an air corridor (e.g., for use by drones), a road, etc. In one embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.11 to establish a wireless local area network (WLAN). In one embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.15 to establish a wireless personal area network (WPAN). In one embodiment, the base station 114b and the WTRUs 102c, 102d may utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, LTE-A Pro, NR, etc.) to establish either a small cell, a picocell, or a femtocell. 1A, the base station 114b may have a direct connection to the Internet 110. Therefore, the base station 114b may not be required to access the Internet 110 via the CN 106 / 115.

[0022] The RAN 104 / 113 may be in communication with the CN 106 / 115, which may be any type of network configured to provide voice, data, application, and / or voice over internet protocol (VoIP) services to one or more of the WTRUs 102a, 102b, 102c, 102d. The data may have various quality of service (QoS) requirements, such as different throughput, latency, error resilience, reliability, data throughput, mobility, etc. The CN 106 / 115 may provide call control, billing services, mobile location-based services, prepaid calling, Internet connectivity, video distribution, etc., and / or perform high-level security functions, such as user authentication. Although not shown in FIG. 1A , it will be appreciated that the RAN 104 / 113 and / or the CN 106 / 115 may be in direct or indirect communication with other RANs employing the same RAT as the RAN 104 / 113 or a different RAT. For example, in addition to being connected to the RAN 104 / 113, which may utilize NR radio technology, the CN 106 / 115 may also be in communication with another RAN (not shown) that employs any of GSM, UMTS, CDMA2000, WiMAX, E-UTRA, or Wi-Fi radio technologies.

[0023] The CN 106 / 115 may also serve as a gateway for the WTRUs 102a, 102b, 102c, 102d to access the PSTN 108, the Internet 110, and / or other networks 112. The PSTN 108 may include a circuit-switched telephone network providing 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 TCP, User Datagram Protocol (UDP), and / or IP in the Transmission Control Protocol / Internet Protocol (TCP / IP) Internet protocol suite. The network 112 may include wired and / or wireless communication networks owned and / or operated by other service providers. For example, the network 112 may include another CN connected to one or more RANs, which may employ the same RAT as the RAN 104 / 113 or a different RAT.

[0024] Some or all of the WTRUs 102a, 102b, 102c, 102d in the communications system 100 may include multi-mode capabilities (e.g., the WTRUs 102a, 102b, 102c, 102d may include multiple transceivers for communicating with different wireless networks over different wireless links). For example, the WTRU 102c shown in FIG. 1A may be configured to communicate with a base station 114a that may employ cellular-based wireless technology and may be configured to communicate with a base station 114b that may employ IEEE 802.11 wireless technology.

[0025] 1B is a system diagram illustrating an example WTRU 102. As shown in FIG. 1B, the WTRU 102 may include, among other things, a processor 118, a transceiver 120, a transmit / receive element 122, a speaker / microphone 124, a keypad 126, a display / touchpad 128, non-removable memory 130, removable memory 132, a power source 134, a Global Positioning System (GPS) chipset 136, and / or other elements / peripherals 138. It will be appreciated that the WTRU 102 may include any sub-combination of the above elements while remaining consistent with an embodiment.

[0026] The processor 118 may be a general-purpose processor, a special-purpose processor, a conventional processor, a digital signal processor (DSP), multiple 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, and / 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. While FIG. 1B depicts the processor 118 and the transceiver 120 as separate components, it will be appreciated that the processor 118 and the transceiver 120 may be incorporated together, for example, in an electronic package or chip.

[0027] The transmit / receive element 122 may be configured to transmit signals to or receive signals from a base station (e.g., base station 114a) over the air interface 116. For example, in one embodiment, the transmit / receive element 122 may be an antenna configured to transmit and / or receive RF signals. In one embodiment, the transmit / receive element 122 may be an emitter / detector configured to transmit and / or receive IR, UV, or visible light signals, for example. In one embodiment, the transmit / receive element 122 may be configured to transmit and / or receive both RF and light signals. It will be appreciated that the transmit / receive element 122 may be configured to transmit and / or receive any combination of wireless signals.

[0028] 1B as a single element, the WTRU 102 may include any number of transmit / receive elements 122. For example, the WTRU 102 may employ MIMO technology. Thus, in one 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 116.

[0029] The transceiver 120 may be configured to modulate signals to be transmitted by the transmit / receive element 122 and demodulate signals received by the transmit / receive element 122. As mentioned above, the WTRU 102 may have multi-mode capabilities. Thus, the transceiver 120 may include multiple transceivers to enable the WTRU 102 to communicate via multiple RATs, such as, for example, NR and IEEE 802.11.

[0030] The processor 118 of the WTRU 102 may be coupled to and may receive user input data from a speaker / microphone 124, a keypad 126, and / or a display / touchpad 128 (e.g., a liquid crystal display (LCD) display unit or an organic light emitting diode (OLED) display unit). The processor 118 may also output user data to the speaker / microphone 124, the keypad 126, and / or the display / touchpad 128. Furthermore, the processor 118 may access information from and store data in any type of suitable memory, such as non-removable memory 130 and / or removable memory 132. The non-removable memory 130 may include random access memory (RAM), 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 other embodiments, the processor 118 may access information from and store data in memory that is not physically located on the WTRU 102, such as on a server or home computer (not shown).

[0031] The processor 118 may receive power from the power source 134 and may be configured to distribute and / or control the power to other components in the WTRU 102. The power source 134 may be any suitable device for powering the WTRU 102. For example, the power source 134 may include one or more dry batteries (e.g., nickel-cadmium (NiCd), nickel-zinc (NiZn), nickel-metal hydride (NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, etc.

[0032] The processor 118 may also be coupled to a GPS chipset 136, which may be configured to provide location information (e.g., longitude and latitude) regarding the current location of the WTRU 102. In addition to, or instead of, information from the GPS chipset 136, the WTRU 102 may receive location information from base stations (e.g., base stations 114a, 114b) over the air interface 116 and / or determine its location based on the timing of when signals are received from two or more nearby base stations. It will be appreciated that the WTRU 102 may acquire location information via any suitable location determination method while remaining consistent with an embodiment.

[0033] The processor 118 may further be coupled to other elements / peripherals 138, which may include one or more software and / or hardware modules / units that provide additional features, functionality, and / or wired or wireless connectivity. For example, the elements / peripherals 138 may include an accelerometer, an electronic compass, a satellite transceiver, a digital camera (for photos and / or videos), a universal serial bus (USB) port, a vibration device, a television transceiver, a hands-free headset, a Bluetooth module, a frequency modulated (FM) radio unit, a digital music player, a media player, a video game player module, an internet browser, a virtual reality and / or augmented reality (VR / AR) device, an activity tracker, etc. The element / peripheral 138 may include one or more sensors, which may be one or more of a gyroscope, an accelerometer, a Hall effect sensor, a magnetometer, an orientation sensor, a proximity sensor, a temperature sensor, a time sensor, a geolocation sensor, an altimeter, a light sensor, a touch sensor, a magnetometer, a barometer, a gesture sensor, a biometric sensor, and / or a humidity sensor.

[0034] The WTRU 102 may include a full-duplex radio where transmission and reception of some or all of the signals (e.g., associated with a particular subframe for both the uplink (e.g., for transmission) and the downlink (e.g., for reception) may be parallel and / or simultaneous. The full-duplex radio may include an interference management unit for reducing and or substantially eliminating self-interference via either hardware (e.g., a choke) or signal processing via a processor (e.g., a separate processor (not shown) or via the processor 118). In one embodiment, the WTRU 102 may include a half-duplex radio that is for transmission and reception of some or all of the signals (e.g., associated with a particular subframe for either the uplink (e.g., for transmission) or the downlink (e.g., for reception)).

[0035] 1C is a system diagram illustrating the RAN 104 and the CN 106, according to one embodiment. As mentioned above, the RAN 104 may employ 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 CN 106.

[0036] The RAN 104 may include eNodeBs 160a, 160b, and 160c, although it will be appreciated that the RAN 104 may include any number of eNodeBs while remaining consistent with an embodiment. The eNodeBs 160a, 160b, and 160c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, and 102c over the air interface 116. In an embodiment, the eNodeBs 160a, 160b, and 160c may implement MIMO technology. Thus, the eNodeB 160a, for example, may use multiple antennas to transmit wireless signals to, and receive wireless signals from, the WTRU 102a.

[0037] Each of the eNodeBs 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 the uplink (UL) and / or downlink (DL), etc. As shown in FIG. 1C, the eNodeBs 160a, 160b, 160c may communicate with one another over an X2 interface.

[0038] 1C may include a mobility management entity (MME) 162, a serving gateway (SGW) 164, and a packet data network (PDN) gateway (PGW) 166. While each of the above elements is shown as part of the CN 106, it will be appreciated that any one of these elements may be owned and / or operated by an entity other than the CN operator.

[0039] The MME 162 may be connected to each of the eNodeBs 160a, 160b, and 160c in the RAN 104 via an S1 interface and may act 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 initial attach of the WTRUs 102a, 102b, 102c, etc. The MME 162 may provide a control plane function for switching between the RAN 104 and other RANs (not shown) that employ other radio technologies, such as GSM and / or WCDMA.

[0040] The SGW 164 may be connected to each of the eNodeBs 160a, 160b, 160c in the RAN 104 via an S1 interface. The SGW 164 may generally route and forward user data packets to / from the WTRUs 102a, 102b, 102c. The SGW 164 may perform other functions such as anchoring the user plane during inter-eNodeB handover, triggering paging when DL data is available for the WTRUs 102a, 102b, 102c, managing and storing the context of the WTRUs 102a, 102b, 102c, etc.

[0041] The SGW 164 may be connected to a PGW 166, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communication between the WTRUs 102a, 102b, 102c and IP-enabled devices.

[0042] The CN 106 may facilitate communication with other networks. For example, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communication between the WTRUs 102a, 102b, 102c and legacy landline communication devices. For example, the CN 106 may include or communicate with an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that acts as an interface between the CN 106 and the PSTN 108. Additionally, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to other networks 112, which may include other wired and / or wireless networks owned and / or operated by other service providers.

[0043] Although the WTRU is described in Figures 1A-1D as a wireless terminal, it is contemplated that in certain representative embodiments, such a terminal may use a wired communication interface with the communication network (e.g., temporarily or permanently).

[0044] In a representative embodiment, the other network 112 may be a WLAN.

[0045] A WLAN in infrastructure basic service set (BSS) mode may have an access point (AP) for the BSS and one or more stations (STAs) associated with the AP. The AP may have access to or interface with a distribution system (DS) or another type of wired / wireless network that carries traffic during and / or from the BSS. Traffic to the STA originating from outside the BSS may arrive through the AP and be delivered to the STA. Traffic originating from the STA to a destination outside the BSS may be sent to the AP for delivery to the respective destination. Traffic between STAs within the BSS may be sent through the AP, e.g., where a source STA may send traffic to the AP, and the AP may deliver the traffic to the destination STA. Traffic between STAs within the BSS may be considered and / or referred to as peer-to-peer traffic. Peer-to-peer traffic may be sent between (e.g., directly between) a source STA and a destination STA via a direct link setup (DLS). In some representative embodiments, the DLS may use 802.11e DLS or 802.11z tunneled DLS (TDLS). A WLAN using an Independent BSS (IBSS) mode may not have an AP, and the STAs within or using the IBSS (e.g., all of the STAs) can communicate directly with each other. The IBSS communication mode is sometimes referred to herein as an "ad hoc" communication mode.

[0046] When using the 802.11ac infrastructure mode of operation or a similar mode of operation, an AP can transmit beacons on a fixed channel, such as a primary channel. The primary channel can be a fixed width (e.g., a 20 MHz wide bandwidth) or a width dynamically set via signaling. The primary channel can be the operating channel of the BSS and can be used by STAs to establish a connection with the AP. In some representative embodiments, carrier sense multiple access with collision avoidance (CSMA / CA) can be implemented, for example, in an 802.11 system. In CSMA / CA, STAs (e.g., every STA), including the AP, can sense the primary channel. If the primary channel is sensed / detected and / or determined to be busy by a particular STA, the particular STA can back off. One STA (e.g., only one station) can transmit at any given time in a given BSS.

[0047] High-throughput (HT) STAs may use, for example, a 40 MHz wide channel for communication via a combination of a primary 20 MHz channel with adjacent or non-adjacent 20 MHz channels to form a 40 MHz wide channel.

[0048] A very high throughput (VHT) STA can support 20 MHz, 40 MHz, 80 MHz, and / or 160 MHz wide channels. A 40 MHz channel and / or an 80 MHz channel can be formed by combining contiguous 20 MHz channels. A 160 MHz channel can be formed by combining eight contiguous 20 MHz channels or by combining two non-contiguous 80 MHz channels, sometimes referred to as an 80+80 configuration. For the 80+80 configuration, after channel encoding, the data can be passed through a segment parser that can split the data into two streams. Inverse fast Fourier transform (IFFT) processing and time-domain processing can be performed separately for each stream. The streams can be mapped onto two 80 MHz channels, and the data can be transmitted by the transmitting STA. At the receiver of the receiving STA, the operations described above for the 80+80 configuration can be reversed, and the combined data can be sent to a medium access control (MAC) layer, entity, etc.

[0049] Sub-1 GHz operating modes are supported by 802.11af and 802.11ah. Channel operating bandwidths and carriers are reduced in 802.11af and 802.11ah relative to those used in 802.11n and 802.11ac. 802.11af supports 5 MHz, 10 MHz, and 20 MHz bandwidths in the TV white space (TVWS) spectrum, while 802.11ah supports 1 MHz, 2 MHz, 4 MHz, 8 MHz, and 16 MHz bandwidths using non-TVWS spectrum. According to a representative embodiment, 802.11ah can support meter-type control / machine-type communication (MTC), such as MTC devices in macro coverage areas. MTC devices can have limited capabilities, including, for example, support for some and / or limited bandwidths (e.g., only support for that). MTC devices can include batteries with above-threshold battery life (e.g., to maintain very long battery life).

[0050] WLAN systems that can support multiple channels and channel bandwidths, such as 802.11n, 802.11ac, 802.11af, and 802.11ah, include a channel that can be designated as a primary channel. The primary channel can have a bandwidth equal to the largest common operating bandwidth supported by all STAs in the BSS. The bandwidth of the primary channel can be set and / or limited by a STA, from among all STAs operating in the BSS, that supports the smallest bandwidth operating mode. In an 802.11ah example, the primary channel may be 1 MHz wide for a STA (e.g., an MTC-type device) that supports (e.g., only supports) the 1 MHz mode, even if the AP and other STAs in the BSS support 2 MHz, 4 MHz, 8 MHz, 16 MHz, and / or other channel bandwidth operating modes. Carrier sensing and / or network allocation vector (NAV) settings may depend on the status of the primary channel. For example, if a STA (that only supports 1 MHz operating mode) transmits to an AP such that the primary channel is busy, the entire available frequency band may be considered busy, even though most of the frequency band may remain idle and available for use.

[0051] In the United States, the available frequency bands that can be used by 802.11ah are 902 MHz to 928 MHz. In South Korea, the available frequency bands are 917.5 MHz to 923.5 MHz. In Japan, the available frequency bands are 916.5 MHz to 927.5 MHz. The total available bandwidth for 802.11ah is 6 MHz to 26 MHz, depending on the country code.

[0052] 1D is a system diagram illustrating the RAN 113 and the CN 115, according to one embodiment. As mentioned above, the RAN 113 may employ NR radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 113 may also be in communication with the CN 115.

[0053] The RAN 113 may include gNBs 180a, 180b, and 180c, although it will be appreciated that the RAN 113 may include any number of gNBs while remaining consistent with an embodiment. The gNBs 180a, 180b, and 180c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, and 102c over the air interface 116. In an embodiment, the gNBs 180a, 180b, and 180c may implement MIMO technology. For example, the gNBs 180a and 180b may utilize beamforming to transmit signals to and / or receive signals from the WTRUs 102a, 102b, and 102c. Thus, the gNB 180a may, for example, use multiple antennas to transmit wireless signals to and / or receive wireless signals from the WTRU 102a. In one embodiment, the gNBs 180a, 180b, 180c may implement carrier aggregation technology. For example, the gNB 180a may transmit multiple component carriers to the WTRU 102a (not shown). A subset of these component carriers may be on an unlicensed spectrum, while the remaining component carriers may be on a licensed spectrum. In one embodiment, the gNBs 180a, 180b, 180c may implement coordinated multi-point (CoMP) technology. For example, the WTRU 102a may receive coordinated transmissions from the gNBs 180a and 180b (and / or 180c).

[0054] The WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using transmissions associated with scalable numerologies. For example, the OFDM symbol spacing and / or OFDM subcarrier spacing may be different for different transmissions, different cells, and / or different portions of the wireless transmission spectrum. The WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using subframes or transmission time intervals (TTIs) of varying or scalable lengths (e.g., including varying numbers of OFDM symbols and / or varying lengths of absolute time duration).

[0055] The gNBs 180a, 180b, 180c may be configured to communicate with the WTRUs 102a, 102b, 102c in a standalone configuration and / or a non-standalone configuration. In a standalone configuration, the WTRUs 102a, 102b, 102c can communicate with the gNBs 180a, 180b, 180c without accessing any other RAN (e.g., eNodeBs 160a, 160b, 160c). In a standalone configuration, the WTRUs 102a, 102b, 102c can utilize one or more of the gNBs 180a, 180b, 180c as mobility anchor points. In a standalone configuration, the WTRUs 102a, 102b, 102c can communicate with the gNBs 180a, 180b, 180c using signals in unlicensed bands. In a non-standalone configuration, the WTRUs 102a, 102b, 102c may communicate / connect with a gNB 180a, 180b, 180c while also communicating / connecting with another RAN, such as an eNodeB 160a, 160b, 160c. For example, the WTRUs 102a, 102b, 102c may implement the DC principle to communicate with one or more gNBs 180a, 180b, 180c and one or more eNodeBs 160a, 160b, 160c substantially simultaneously. In a non-standalone configuration, the eNodeBs 160a, 160b, 160c may act as mobility anchors for the WTRUs 102a, 102b, 102c, and the gNBs 180a, 180b, 180c may provide additional coverage and / or throughput for serving the WTRUs 102a, 102b, 102c.

[0056] Each of the gNBs 180a, 180b, 180c 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 the UL and / or DL, support for network slicing, dual connectivity, interworking between NR and E-UTRA, routing of user plane data to user plane functions (UPFs) 184a, 184b, routing of control plane information to access and mobility management functions (AMFs) 182a, 182b, etc. As shown in FIG. 1D, the gNBs 180a, 180b, 180c may communicate with one another via an Xn interface.

[0057] 1D may include at least one AMF 182a, 182b, at least one UPF 184a, 184b, at least one Session Management Function (SMF) 183a, 183b, and at least one Data Network (DN) 185a, 185b. While each of the above elements is shown as part of the CN 115, it will be appreciated that any of these elements may be owned and / or operated by an entity other than a CN operator.

[0058] The AMF 182a, 182b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 113 via an N2 interface and may act as a control node. For example, the AMF 182a, 182b may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, supporting network slicing (e.g., handling different protocol data unit (PDU) sessions with different requirements), selecting a particular SMF 183a, 183b, managing registration areas, terminating NAS signaling, mobility management, etc. Network slicing may be used by the AMF 182a, 182b to customize CN support for the WTRUs 102a, 102b, 102c, for example, based on the type of service being utilized by the WTRUs 102a, 102b, 102c. For example, different network slices may be established for different use cases, such as services relying on Ultra-Reliable Low Latency (URLLC) access, services relying on enhanced Massive Mobile Broadband (eMBB) access, services for MTC access, etc. The AMF 162 may provide a control plane function for switching between the RAN 113 and other RANs (not shown) that employ other radio technologies such as LTE, LTE-A, LTE-A Pro, and / or non-3GPP access technologies such as Wi-Fi.

[0059] The SMFs 183a and 183b may be connected to the AMFs 182a and 182b in the CN 115 via an N11 interface. The SMFs 183a and 183b may also be connected to the UPFs 184a and 184b in the CN 115 via an N4 interface. The SMFs 183a and 183b may select and control the UPFs 184a and 184b and configure the routing of traffic through the UPFs 184a and 184b. The SMFs 183a and 183b may perform other functions, such as managing and allocating UE IP addresses, managing PDU sessions, controlling policy enforcement and QoS, providing downlink data notification, etc. The PDU session type may be IP-based, non-IP-based, Ethernet-based, etc.

[0060] The UPFs 184a, 184b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 113 via an N3 interface, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks such as the Internet 110, for example, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices. The UPFs 184, 184b may perform other functions such as routing and forwarding packets, enforcing user plane policies, supporting multi-homed PDU sessions, handling user plane QoS, buffering downlink packets, providing mobility anchoring, etc.

[0061] The CN 115 may facilitate communication with other networks. For example, the CN 115 may include or communicate with an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that acts as an interface between the CN 115 and the PSTN 108. Additionally, the CN 115 may provide the WTRUs 102a, 102b, 102c with access to other networks 112, which may include other wired and / or wireless networks owned and / or operated by other service providers. In one embodiment, the WTRUs 102a, 102b, 102c may be connected to the local data networks (DNs) 185a, 185b through the UPFs 184a, 184b via an N3 interface to the UPFs 184a, 184b and an N6 interface between the UPFs 184a, 184b and the DNs 185a, 185b.

[0062] 1A-1D and the corresponding description thereof, one or more, or all, of the functions described herein with respect to any of the WTRUs 102a-d, base stations 114a-b, eNodeBs 160a-c, MME 162, SGW 164, PGW 166, gNBs 180a-c, AMFs 182a-b, UPFs 184a-b, SMFs 183a-b, DNs 185a-b, and / or any other element / device(s) described herein may be performed by one or more emulation elements / devices (not shown). The emulation devices may be one or more devices configured to emulate one or more, or all, of the functions described herein. For example, the emulation devices may be used to test other devices and / or to simulate network and / or WTRU functionality.

[0063] The emulation device may be designed to implement one or more tests of other devices in a laboratory environment and / or in a carrier network environment. For example, one or more emulation devices may perform one or more, or all, functions while fully or partially implemented and / or deployed as part of a wired and / or wireless communication network to test other devices in the communication network. One or more emulation devices may perform one or more, or all, functions while temporarily implemented / deployed as part of a wired and / or wireless communication network. The emulation device may be directly coupled to another device for testing purposes and / or may perform testing using over-the-air wireless communication.

[0064] The one or more emulation devices may perform one or more functions, inclusive, while not being implemented / deployed as part of a wired and / or wireless communication network. For example, the emulation devices may be utilized in test labs and / or test scenarios in non-deployed (e.g., test) wired and / or wireless communication networks to implement testing of one or more components. The one or more emulation devices may be test equipment. Direct RF coupling and / or wireless communication via RF circuitry (which may, for example, include one or more antennas) may be used by the emulation devices to transmit and / or receive data.

[0065] In a supercell that includes an SSB with multiple PCIs, the amount of system information (SI) transmissions may increase with the number of PCIs. In the following description, methods and apparatus are provided to propose various enhancements to reduce the overhead associated with SI transmissions in a supercell.

[0066] Extended capture of SI messages carrying SI other than MIB and SIB1 may be considered. Instead of receiving SI messages using the PCI of the detected SSB, the WTRU 102 (e.g., UE) may use the anchor PCI for SI message reception. This may introduce the possibility of joint transmission of SI messages in a super-cell.

[0067] Further enhanced SI message acquisition may contemplate joint transmission of SI messages using groups of SSB beams, thereby reducing the need to time-multiplex SI message transmissions corresponding to different SSBs.

[0068] Cell-free MIMO deployment

[0069] Wireless communication between one or more WTRUs 102 (e.g., UEs) and a network is contemplated herein. For example, the network may include transmit and receive points (TRPs) in the vicinity of a particular WTRU 102 (e.g., UE). A TRP may be referred to interchangeably as a "distributed antenna system" (DAS), a "remote radio head" (RRH), an "access point" (AP), or distributed MIMO in various circumstances.

[0070] A TRP may both transmit signals and / or channels to one or more WTRUs 102 (e.g., UEs), typically referred to as the downlink (DL), and receive signals and / or channels from one or more WTRUs 102 (e.g., UEs), typically referred to as the uplink (UL). In some cases, a TRP may act as a WTRU 102 (e.g., UE), e.g., when acting as a repeater, the TRP may act as a WTRU 102 (e.g., UE) and interact with another node to receive DL data that may then be relayed to the WTRU 102 (e.g., UE), or the TRP may act as a WTRU 102 (e.g., UE) and relay UL data received from the WTRU 102 (e.g., UE) to the base station.

[0071] 2 shows a diagram of points related to TRP(s) and / or RP. In (a), there are two geographically separated points, a TRP and an RP, in the vicinity of a WTRU 102 (e.g., a UE). In (b), there are two TRPs in approximately the same geographic location in the form of two antennas (denoted by "Ant" in the diagram) mounted on the same site, but with their main transmission / sensitivity directions (boresight) in significantly different directions. In (c), there are two panels, each associated with a point, each comprising a rectangular array of cross-polarized antenna elements (in the form of an "X" in the diagram). Each panel is connected to a different TRX chain in this diagram.

[0072] With respect to TRPs, the different points may be geographically separated (see FIG. 2(a)). In some cases, the different points may be located at approximately the same geographic location, but may be separated in some other way, for example, the boresight(s) of the antenna(s) (or antenna element(s)) of a first point is significantly different from the boresight(s) of the antenna(s) of a second point.

[0073] An example of the latter is a cellular communication site that uses different sets of antennas to serve multiple sectors in different directions. In this case, the different sets of antennas serving different sectors in different directions from the site can be considered different points. This is shown in Figure 2(b).

[0074] According to embodiments, antennas may be arranged in one or more panels, where the panels include, for example, rectangular panels with N×M antenna elements, as shown in FIG. 2(c). According to embodiments, all or a subset of the antenna elements of a panel may be connected to the same transmitter and receiver (TRX) chain or the same receiver (RX) chain. According to embodiments, antenna elements of different panels may be connected to different transmitter and receiver (TRX) chains or different receiver (RX) chains. According to embodiments, different panels, which may or may not be geographically collocated, may correspond to different points. According to embodiments, different panels may correspond to the same point.

[0075] According to an embodiment, a point may operate on multiple frequencies, for example, two frequencies. According to an embodiment, a site (e.g., including one antenna, an antenna array, a panel, or a subset of antennas per frequency) in a geographic location with specific transmit / receive directions on multiple frequencies may count as multiple points, at least from the perspective of a WTRU (e.g., UE). One reason may be that radio signal propagation characteristics on different frequencies are different. Another reason may be that hardware on the network side, such as different oscillators, calibration hardware for beam alignment, phase shifters for beamforming, etc., introduces signal transmission and / or reception differences on different frequencies.

[0076] Signals / channels received at the TRP may undergo further processing, e.g., filtering, amplification, downconversion, A / D conversion (sampling), digital signal processing, demodulation, channel decoding, etc. Signals / channels transmitted at the TRP may undergo various processing prior to transmission, e.g., filtering, amplification, peak-to-average power reduction, upconversion, D / A conversion, digital signal processing, modulation, channel encoding, etc. A subset (e.g., none, some, or all) of these operations for reception / transmission may be performed at the TRP, while other operations may be performed at one or more other locations connected to the TRP, e.g., through fronthaul or backhaul links, e.g., by optical fiber, copper wire, over the air, etc. In a Centralized RAN (CRAN) implementation, signal processing for multiple points is performed at a centralized location.

[0077] Massively Distributed MIMO

[0078] The additional TRPs in a cell may provide a reduced average distance and / or path loss between the WTRU 102 (e.g., a UE) and the nearest TRP, allowing, for example, lower transmit power and lower interference in the system. The additional TRPs in a cell may improve spatial diversity, which means that there may be several candidate TRPs that can serve the WTRU 102 (e.g., a UE). If the radio link to the serving TRP is blocked, the WTRU 102 (e.g., a UE) may instead be served by another TRP that does not have a blocked radio link.

[0079] In a distributed MIMO system, antennas may not be located in one or a few TRPs. Instead, the antennas are more distributed throughout the wireless network. In some definitions, distributed MIMO may include, for example, coherent joint transmission / reception involving several TRPs, in cases with several TRPs.

[0080] A massively distributed MIMO system (also called distributed massive MIMO) may combine a large number of antennas in a massive MIMO system with distributed antennas in a distributed MIMO system. For example, hundreds of antennas pre-colocated in a massive MIMO TRP covering a geographic area may be distributed throughout the area. A subset of antennas may be co-located at a TRP (sometimes called an access point). Massively distributed MIMO deployments may offer very high theoretical performance under ideal assumptions. However, in practice, there are numerous challenges to achieving these performance improvements, including fronthaul, synchronization, etc.

[0081] Selfie MIMO

[0082] Legacy cellular networks are based on the concept that (typically) a small number of TRPs transmit and receive signals corresponding to cells in a frequency band. A frequency band in which multiple cells operate is sometimes referred to as a frequency layer, which may be characterized by a range of frequencies, a center (e.g., carrier) frequency, a bandwidth, etc. Different cells on a frequency layer may use the same or different center frequencies and / or bandwidths.

[0083] The geographic area served by a cell may typically be static. As a WTRU 102 (e.g., a UE) moves through the network, it may be handed over (e.g., may need to be handed over) from cell to cell. Intra-frequency handovers, i.e., handovers between cells in the same frequency band, typically occur at cell edges where service quality is typically lower.

[0084] The idea of ​​cell-free operation is that instead of moving across more or fewer static cells, the cell serving the WTRU 102 (e.g., UE) may move along with the WTRU 102 (e.g., UE). From the WTRU 102's (e.g., UE's) perspective, intra-frequency handover may not be used, or at least much less intra-frequency handover may be used (e.g., required).

[0085] Another potential advantage of cell-free operation may be that degradation of service quality at the cell edge may be avoided by having the WTRU 102 (e.g., UE) serve a set of nearby TRPs rather than using a set of TRPs that may be associated (e.g., may need to be associated) with the serving cell.

[0086] Cell-free operation in a massively distributed MIMO deployment is sometimes referred to as cell-free MIMO. A WTRU-centric "cell" may be operated by a TRP / antenna close to the WTRU 102 (e.g., UE), which results in high and uniform quality of service.

[0087] SS / PBCH Block (SSB) in 5G NR

[0088] The SS / PBCH block (SSB) is the signal / channel in 5G NR that is most commonly used for cell-based operation.

[0089] The SSB may include a primary synchronization signal (PSS), a secondary synchronization signal (SSS), a physical broadcast channel (PBCH), and a PBCH demodulation reference signal (DMRS).

[0090] For example, depending on the frequency range of the cell, there may be at most 4, 8, or 64 SSBs in a cell. Lower frequencies may support fewer SSBs, while higher frequencies, e.g., millimeter wave, may support at most 64 SSBs in a cell. Different SSBs may correspond to different SSB indices.

[0091] For various reasons, an SSB (with a certain SSB index) may not be transmitted on the nominal time-frequency resource assigned to that SSB. It may be more preferable to denote the SSB as a candidate SSB and the SSB index as a candidate SSB index. For simplicity, the terms SSB and SSB index are used herein, but they may refer to candidate SSBs and candidate SSB indexes, respectively.

[0092] Physical Cell ID (PCI)

[0093] The Physical Cell Id (PCI) may be used to identify a cell on a carrier frequency, which may be used to generate various cell-specific signals / channels, such as PSS and SSS.

[0094] NR PCI

[0095]

number

[0096] have two other IDs,

[0097]

number

[0098] and

[0099]

number

[0100] from,

[0101]

number

[0102] It can be constructed as:

[0103] Primary Synchronization Signal (PSS)

[0104] The PSS may be used by the WTRU 102 (e.g., a UE), for example, for cell search and / or coarse time and frequency synchronization. The sequence used for the PSS may be:

[0105]

number

[0106] may be based on

[0107] Secondary Synchronization Signal (SSS)

[0108] The SSS may be used by the WTRU 102 (e.g., a UE) for, for example, further synchronization, channel estimation, and / or SSB-based measurements, e.g., reference signal received power (RSRP), and determining PCI.

[0109]

number

[0110] and

[0111]

number

[0112] The method may be based on both.

[0113] Physical Broadcast Channel Demodulation Reference Signal (PBCH DMRS)

[0114] The PBCH DMRS may be used by the WTRU 102 (eg, a UE) in addition to the SSS, for example, for further synchronization, channel estimation, and SSB-based measurements.

[0115] The PBCH DMRS sequence may be based on any of: (1) the PCI, (2) the SSB index, (3) its least significant bit (LSB), and (4) the half-frame index. The WTRU 102 (e.g., a UE) may acquire some subframe and / or frame timing upon reception of the PBCH DMRS.

[0116] A subcarrier offset based on (eg, dependent on) PCI mod4 may be applied to the PBCH DMRS.

[0117] Physical Broadcast Channel (PBCH)

[0118] The PBCH payload may include a Master Information Block (MIB) and timing-related information (8 bits) that may not be included in the MIB. The timing-related information may include the most significant bit (MSB) of the SSB index and / or half-frame index.

[0119] MIB

[0120] The MIB may include information for (eg, necessary for) receiving SIB1 as well as other information, as described in the table below.

[0121] [Table 1-1]

[0122] [Table 1-2]

[0123] Some cells may not support initial access and may not provide, i.e., may not transmit, SIB1. SSB Some values ​​of may indicate that SIB1 is not broadcast on the cell. If the WTRU 102 (e.g., a UE) cannot proceed with initial access on the cell, it may not know (e.g., need not know) the subcarrier offset.

[0124] If a cell provides SIB1, the field pdcch-ConfigSIB1 may correspond to an IE with a 4-bit field (controlResourceSetZero) that determines a common CORESET with ID#0 and / or a 4-bit field (searchSpaceZero) that determines a common search space with ID#0.

[0125] The cell does not provide SIB1, i.e., k SSB If is within a certain range, k SSB The value of and / or pdcch-ConfigSIB1 may provide an indication of another global synchronization channel number (GSCN) that provides SIB1.

[0126] SIB1 in 5G NR

[0127] System information in 5G NR may be divided into multiple parts called system information blocks (SIBs). One or more SIBs may be carried in a PDSCH that may be broadcast in a cell. Different SIBs may correspond to different types of system information. A WTRU 102 (e.g., a UE) may choose to receive (e.g., only) a subset of the SIBs.

[0128] SIB1 includes various system information, e.g., how to perform random access to connect to a cell and / or scheduling information for other SIBs. During initial access, the WTRU 102 (e.g., a UE) may receive SIB1, which may be broadcast in the cell. For handover or serving cell addition, the content of SIB1 may be conveyed using dedicated signaling. Now, the broadcast of SIB1, which may be received by the WTRU 102 (e.g., a UE), e.g., in IDLE mode, is described.

[0129] MIB and SIB1 may contain minimum system information.

[0130] SIB1 Scheduling and Transmission

[0131] The cell broadcasting SIB1 may configure CORESET#0 and / or search space#0 in a field pdcch-ConfigSIB1 in the MIB, which may indicate where the WTRU 102 (e.g., a UE) can receive a PDCCH that may schedule a PDSCH carrying SIB1. The slots and / or symbols at which the WTRU 102 (e.g., a UE) can receive and decode the PDCCH may use (e.g., depend on) the SSB index of the detected SSB. There may be a one-to-one association between SSBs and disjoint sets of time-multiplexed PDCCH monitoring opportunities. The association may imply that the WTRU 102 (e.g., UE) may receive the PDCCH using the same time-frequency synchronization and / or spatial parameters (e.g., WTRU Rx beam) as used to receive the SSB, i.e., the WTRU 102 (e.g., UE) may operate (e.g., assume) that the PDCCH and PDSCH are quasi-colocated (QCL) with the corresponding SSB. This may provide support for SSB-based early beam management prior to system information acquisition.

[0132] The periodicity of the search space associated with an SSB may be two radio frames or equal to the SSB periodicity, depending on the CORESET multiplexing pattern. The PDSCH carrying SIB1 may be transmitted with the same periodicity.

[0133] The PDCCH and PDSCH for SIB1 may be received within an initial DL bandwidth part (BWP) that spans the bandwidth of CORESET#0. That bandwidth may (e.g., typically) be relatively low, which may mean that PDSCHs corresponding to different SSBs may typically be multiplexed in time rather than in frequency. Some TRPs may not be able to transmit simultaneously using multiple different SSB beams. For example, due to the time multiplexing of both the PDCCH and PDSCH for SIB1, the number of symbols and overhead used for SIB1 transmission may increase with the number of SSBs.

[0134] FIG. 3 shows an example cell with two TRPs and two SSB beams per TRP. Thus, the number of SSBs in the cell is four. Different patterns in the SSB beams may correspond to different SSBs, e.g., different SSB indices. FIG. 4 shows transmission of four SSBs in a cell using CORESET multiplexing pattern 1 with a corresponding CORESET / search space for reception of a PDCCH that schedules a PDSCH carrying SIB1. In this pattern, CORESET#0 may at least partially overlap in frequency with the SSBs. Each of the four shown PDCCH monitoring opportunities may correspond to a different SSB, such that the WTRU 102 (e.g., UE) may operate (e.g., assume) that the PDCCH (including its DMRS) is QCL'd with the corresponding SSB. System information broadcast overhead may increase with the number of SSBs in a cell. The arrows in the figure between the PDCCH and the corresponding PDSCH may transmit information indicating that the PDSCH is scheduled by the PDCCH.

[0135] In CORESET multiplexing pattern 2, PDCCH monitoring opportunities for CORESET#0 may occur (e.g., immediately) before and with the same periodicity as the corresponding SSBs. In CORESET multiplexing pattern 3, PDCCH monitoring opportunities for CORESET#0 may occur simultaneously with and / or with the same periodicity as the corresponding SSBs. In patterns 2 and 3, the frequency resources for CORESET#0 may not overlap with the SSBs.

[0136] SIB1 Content

[0137] SIB1 may (eg, typically) contain various cell configurations that may be used (eg, required) to access a cell.

[0138] SIB1 may contain various cell barring information, such as cell barred indication for NTN, cell barred indication for reduced capability WTRU 102 (e.g., UE), unified access control, etc. In other words, various cell barring may be indicated in both the MIB and SIB1.

[0139] SIB1 may indicate scheduling information for other SIBs, for example, in an SI-SchedulingInfo information element (IE). The other SIBs may be included in an SI message, where the SI message may include one or more SIBs. SIB1 may indicate that the SI message is broadcast or not broadcast in the cell. If the SI message is not broadcast, the WTRU 102 (e.g., a UE) may request that it be broadcast.

[0140] An SI area may include the set of cells for which the SIB is valid. SIB1 may indicate an SI area ID and / or a per-SIB indication (for other SIBs) if it is cell-specific or SI area-specific. SIB1 may indicate a SIB value tag, e.g., an integer between 0 and 31, that may be used to indicate that the corresponding SIB has changed, e.g., a version number.

[0141] Other SIBs in 5G NR

[0142] The term "other SIB" may correspond to an SIB other than MIB and SIB 1. For example, 5G NR Rel-17 specifies SIBs up to SIB 21.

[0143] The WTRU 102 (e.g., a UE) may acquire a subset of other SIBs, depending on, e.g., its capabilities, needs, etc. The WTRU 102 (e.g., a UE) may acquire SI based on, for example, any of the following: upon cell selection (e.g., upon power up), upon cell reselection, upon return from out-of-coverage, after reconfiguration with synchronization complete, after entering a network from another radio access technology, upon receiving an indication that system information has changed, upon receiving a public warning system (PWS) notification, upon receiving a request from higher layers (e.g., a positioning request), and whenever the WTRU 102 (e.g., a UE) does not have a valid version of the SIB stored or a valid version of the requested SIB.

[0144] The WTRU 102 (e.g., a UE) may store the acquired SIB and various parameters associated with the SIB. If the stored SIB is (e.g., still) valid for the cell, the WTRU 102 (e.g., a UE) may not reacquire (e.g., may not need to reacquire) the SIB.

[0145] For example, if a stored SIB is associated with a cell, e.g., it was received at the cell and had the same stored SIB value tag as the SIB value tag included in the latest SIB scheduling information received from the cell (e.g., in the SI-SchedulingInfo IE), the stored SIB may be (e.g., still) valid for the cell.

[0146] In another example, the WTRU 102 (e.g., a UE) may (e.g., initially) acquire a SIB in a first cell with a first SI tracking area ID and with a first SIB value tag, and the WTRU 102 (e.g., UE) may store the acquired SIB and associated parameters. The stored SIB may be valid in a second cell if the latest SIB scheduling information received from the second cell (e.g., in an SI-SchedulingInfo IE) includes the same SI tracking area ID and the same SIB value tag as those associated with the stored SIB.

[0147] The search space set for monitoring a PDCCH that schedules a PDSCH carrying an SI message (e.g., a Type0A-PDCCH common search space set) may be the same as or different from the search space set for monitoring a PDCCH that schedules a PDSCH carrying SIB1 (e.g., a Type0-PDCCH common search space set). The search space set for receiving SI messages may be configured in SIB1, for example, using the searchSpaceOtherSystemInformation parameter. The WTRU 102 (e.g., a UE) may monitor the PDCCH to receive SI messages in an SI window, which may have a configurable duration for the SI messages.

[0148] Cell-free MIMO deployments may be (e.g., attractive) alternatives to legacy cell-based (cellular) networks: the overhead and potential disruptions associated with handling cells may be reduced while the benefits of multi-TRP-based operation are preserved.

[0149] Two aspects of legacy systems that may be (e.g., fundamentally) linked to a cell are cell search and system information acquisition. In 5G NR, for example, cell search may be based on SSBs, where different SSBs may be transmitted from different TRPs or using different Tx beams from the TRP. System information distribution may (e.g., also) be connected to SSBs, since system information transmission may be repeated for each SSB.

[0150] In existing 5G NR specifications, there can be at most four or eight SSBs in FR1 and at most 64 SSBs in FR2. Different SSBs in a cell can be time-multiplexed. One reason may be that this allows base stations to be implemented using analog beamforming, where a single Tx beam can be used at a time. Another reason may be that this allows all available base station transmit power to be allocated to one SSB, thereby maximizing SSB coverage. SSBs may be fundamental signals for various aspects of 5G NR, such as time-frequency synchronization, as well as beam management and mobility measurements. In systems with multiple TRPs and / or TRPs with hybrid / digital beamforming, time-multiplexing of SSBs may not be necessary.

[0151] In future cell-free MIMO deployments, the number of TRPs and beams may increase dramatically. Therefore, a much larger number of SSBs (or equivalent system information acquisition and cell search) may be used (e.g., may be required). The increased number of SSBs may result in increased overhead from system information transmission. Therefore, the following problem may be explored herein: reducing the overhead from system information message transmission when the number of SSBs may be increased.

[0152] Enhanced capture of SI messages

[0153] MIB and SIB1

[0154] In a supercell, SSBs with different PCIs may be used. The set of PCIs used for SSBs in a supercell may be denoted as P.

[0155] The MIB and SIB1 may be captured by the WTRU 102 (e.g., a UE) as in legacy 5G NR. SIB1 may be broadcast for different PCIs in the super-cell, for example, for all PCIs or a subset of PCIs in P.

[0156] For reference, an exemplary legacy initial access procedure is described below and may include any of the following steps: 1. The WTRU 102 (eg, a UE) may detect the SSB. 2. The WTRU 102 (eg, a UE) may decode the PBCH payload in the SSB, including the MIB. 3. The WTRU 102 (eg, UE) may determine cell timing (eg, SFN, half-frame, symbol timing) from the SSB and / or PBCH payload. 4. The WTRU 102 (eg, a UE) may determine that CORESET#0 and a corresponding Type0-PDCCH common search space set may exist, and may determine the time-frequency resources for the CORESET and search space set from the PBCH payload. 5. The WTRU 102 (eg, a UE) may receive (eg, successfully) the PDCCH on the CORESET and / or search space set and may decode the DCI, which may include PDSCH scheduling information. 6. The WTRU 102 (eg, a UE) may receive the PDSCH and / or decode the transport block, which may include SIB1.

[0157] The legacy SIB1 PDCCH and / or SIB1 PDSCH may involve PCI-specific parameters, such as PDCCH / PDSCH DMRS sequence generation, interleaved CCE-to-REG mapping (e.g., shift index parameters), and PDCCH / PDSCH scrambling. Because a super-cell may include SSBs with multiple PCIs (in P), and the WTRU 102 (e.g., UE) may receive SIB1 using the PCI of the detected SSB, a separate SIB1 PDCCH and SIB1 PDSCH may be used (e.g., required) for each PCI in the super-cell that may provide SIB1. SIB1 may be additionally repeated for each SSB.

[0158] One or more of various PBCH / MIB parameters, such as the system frame number, the subcarrier spacing for SIB1 (e.g., subCarrierSpacingCommon), the subcarrier offset from the SSB to the resource block grid (e.g., ssb-SubcarrierOffset), the position of the first DMRS symbol (e.g., dmrs-TypeA-Position), may be (e.g., may need to be) aligned across the PCI in the supercell.

[0159] SIB1 may be sent per PCI and per SSB, but the distribution of other SIBs may be extended.

[0160] Extended capture of SI message(s)

[0161] A method and apparatus are proposed to support reduced transmission of one or more SI messages (carrying one or more other SIBs) from a TRP in a supercell compared to per PCI and per SSB transmission of SI messages. A method and apparatus are proposed to improve SI message reception reliability. This can be achieved by two extensions. A WTRU 102 (e.g., a UE) that detected an SSB and received SIB1 using a first PCI may receive an SI message using a second PCI, referred to as the anchor PCI. The anchor PCI may be indicated in SIB1 or determined by a rule, as disclosed further below, for example, in the "Other SIB Acquisition Using the Anchor PCI" section below. The WTRU 102 (e.g., UE) that detected the first SSB and received SIB1 based on the first SSB may receive an SI message using a group of SSBs that may include the first SSB. Receiving the SI message using the group of SSBs may correspond to operating (e.g., assuming) the group of SSBs as a quasi-co-located source for SI message reception and determining the same time-frequency locations for the PDCCH (e.g., CORESET and search space set) for the SSBs in the group of SSBs. This is further disclosed in the "Other SIB Acquisition Using Groups of SSBs" section below.

[0162] Other SIB capture using anchor PCI

[0163] One, multiple, or all other SIBs may be valid across the entire super-cell, for example, regardless of the PCI of the SSB detected by the WTRU 102 (e.g., UE). Consider an SI message that includes other SIBs that are valid across the entire super-cell. Rather than time-multiplexing a first PDCCH / PDSCH with a first PCI that schedules / carries an SI message with a second PDCCH / PDSCH with a second PCI that schedules / carries an SI message, it may be beneficial to jointly transmit the PDCCH / PDSCH across PCIs.

[0164] Such a scheme is shown in FIG. 5. Eight SSBs with two PCIs are transmitted in a supercell. The SSBs / PDCCHs / PDSCHs with a white background correspond to the first PCI, and the SSBs with a gray background correspond to the second PCI. SI windows corresponding to SI messages are shown, with different PDCCH monitoring opportunities corresponding to different SSB indices. Note that the figure does not show SIB1. However, since per PCI SIB1 may be operated (e.g., it may be assumed), a WTRU 102 (e.g., UE) that detects an SSB with a first PCI may receive SIB1 corresponding to the first PCI, and a WTRU 102 (e.g., UE) that detects an SSB with a second PCI may receive SIB1 corresponding to the second PCI. According to an embodiment, extended SIB1 transmission may be applicable. In this example, the first PCI is the anchor PCI, which means that SI messages may be received using the first PCI. The SIB1 corresponding to the second PCI may indicate the same configuration as the SIB1 corresponding to the first PCI for receiving SI messages, but with an additional indication that the corresponding PDCCH and PDSCH may be received using the first PCI. Receiving a PDCCH using the anchor PCI may involve, for example, changing the parameters in PDCCH DMRS sequence generation, interleaved CCE to REG mapping (e.g., shift index parameters), PDCCH scrambling, etc.

[0165]

number

[0166] Receiving the PDSCH using the anchor PCI may include, for example, using the parameter

[0167]

number

[0168] The WTRU 102 (e.g., UE) may use the anchor PCI as the QCL source for the SI messages. Although the WTRU 102 (e.g., UE) receives the SI messages using the anchor PCI, the WTRU 102 (e.g., UE) may operate with (e.g., assume) the SI messages PDCCH and PDSCH are QCL'd with the detected SSB. In some embodiments, the WTRU 102 (e.g., UE) may operate with (e.g., assume) both the detected SSB and an SSB with the same index as the detected SSB but where the anchor PCI is the QCL source for the SI messages PDCCH and PDSCH.

[0169] An exemplary WTRU (e.g., UE) procedure is shown in Figure 6. In step 601, the WTRU 102 (e.g., UE) may detect an SSB with a first PCI and may decode the corresponding PBCH, which may include a MIB, similar to legacy procedures. In step 602, the WTRU 102 (e.g., UE) may receive a PDCCH, which may schedule a PDSCH, which may carry SIB1, based on, for example, a configuration in the MIB, which may also follow legacy procedures.

[0170] In step 603, the WTRU 102 (e.g., UE) may determine whether reception of the SI message is based on the anchor PCI. If so, the WTRU 102 (e.g., UE) may receive the SI message using the anchor PCI in step 605. According to an embodiment, both the PDCCH and the PDSCH may be received using the anchor PCI. According to an embodiment, the PDCCH may be received using the first PCI, while the PDSCH may be received using the anchor PCI. The PDCCH, which may schedule the PDSCH, which may carry the SI message, may indicate whether the PDSCH should be received using the first PCI or the anchor PCI. SIB1 may indicate the anchor PCI. SIB1 or another SIB may indicate the set of PCIs (P) used in the super-cell.

[0171] If the SI message is received using an anchor PCI, which may be different from the first PCI, the WTRU 102 (e.g., UE) may use the detected SSB with the first PCI as a QCL source when (e.g., when) receiving the PDCCH and / or PDSCH. According to an embodiment, the WTRU 102 (e.g., UE) may use an SSB with the anchor PCI but with the same SSB index as the detected SSB as a QCL source. According to an embodiment, the WTRU 102 (e.g., UE) may use the detected SSB (with the first PCI) and the same SSB (with the anchor PCI) as a QCL source when (e.g., when) receiving the SI message PDCCH and / or PDSCH.

[0172] If SIB1 did not indicate SI message reception using the anchor PCI, the WTRU 102 (eg, a UE) may receive the SI message using the first PCI at step 604.

[0173] For example, to support SIB acquisition using an anchor PCI with joint transmission using SSB beams corresponding to different PCIs, various configurations may be (e.g., may need to be) arranged across SIB1s with different PCIs in a super-cell. For example, parameters corresponding to a SIB1-defined resource block grid and DL BWP may be (e.g., may need to be) arranged across SIB1s. CORESET and search space set configurations for a PDCCH that schedules a PDSCH carrying an SI message may be (e.g., may need to be) arranged such that the same PDCCH can be decoded by a WTRU 102 (e.g., UE) that decoded a SIB1 with a different PCI in a super-cell.

[0174] There may be multiple SI messages, including sets of other SIBs, that may be configured in SIB1. The extension may apply to a subset or all of the SI messages. Because per-PCI delivery of SIB1 may be enabled (e.g., assumed), different SIB1s may include different configurations in some respects. For example, different SIB1s may indicate that different sets of SI messages may be delivered using the anchor PCI.

[0175] In some representative embodiments, joint transmission by multiple TRPs may correspond to single frequency network (SFN) transmission, such as when the TRPs transmit the same signal and / or channel. In some embodiments, joint transmission by multiple TRPs may correspond to transmission of different signals and / or channels on overlapping time-frequency resources, such as by using different antenna ports associated with PDSCH transmission. For example, in SIB1, the anchor PCI may be indicated for all SI messages, e.g., directly in the SI-SchedulingInfo IE, or for each SI message, e.g., in the SchedulingInfo IE or SIB-TypeInfo IE. According to an embodiment, the WTRU 102 (e.g., UE) may assume that the broadcast status of an SI message, e.g., “broadcasting” or “not broadcasting,” as indicated in SIB1, may be the same across all PCIs or a subset of PCIs in the super-cell, e.g., SIB1 corresponding to a subset of PCIs for which SIB1 may indicate the same anchor PCI for the SI message. All PCIs or a subset of PCIs of a supercell may belong to the same SI area, for example, by having the same SI area ID indicated in the corresponding SIB1.

[0176] DCI-based indications

[0177] The anchor PCI may be indicated by the DCI carried by the PDCCH, for example as index p in P.

[0178] According to an embodiment, SIB1 may constitute a subset of PCIs from P from which the DCI may point to the anchor PCI, which may reduce DCI overhead as the size of P may be large.

[0179] The first PCI may or may not be included among the PCIs that may be indicated by the DCI. In some cases, a bit in the DCI may indicate whether the first PCI should be used or whether the anchor PCI indicated in SIB1 should be used.

[0180] An exemplary WTRU (e.g., UE) procedure is shown in FIG. 7. Steps 701 and 702 may follow the WTRU (e.g., UE) procedure in FIG. 6. SIB1 may indicate whether DCI-based anchor PCI indication should be used. If the WTRU 102 (e.g., UE) determines not to be the case in step 703, the WTRU 102 (e.g., UE) may use legacy SI message reception using the first PCI. If the WTRU 102 (e.g., UE) determines DCI-based anchor PCI indication should be used in step 703, it may proceed to determining whether the decoded DCI indicates whether the PDSCH carrying the SI message should be received using the first PCI (as in legacy operation) or the anchor PCI. In the former case, the WTRU 102 (e.g., UE) may proceed to step 705 and / or receive the PDSCH using the first PCI. In the latter case, the WTRU 102 (eg, a UE) may proceed to step 706 and / or may receive the PDSCH using the anchor PCI.

[0181] Other SIB capture using SSB groups

[0182] PDCCH monitoring opportunities for scheduling PDSCHs carrying SI messages corresponding to different SSBs may be time-multiplexed in legacy 5G NR. Typically, the corresponding PDSCHs may (e.g., also) be time-multiplexed. A time-multiplexing approach may have the advantage that it may enable analog beamforming implementation and allocation of all DL transmit power to SI message PDCCH / PDSCH in a single TRP cell. A disadvantage may be that it may occupy many time-frequency resources, especially many resources in time, which may result in high network power consumption. Time-multiplexing may result in longer SI acquisition latency because the WTRU 102 (e.g., UE) may wait (e.g., may need to wait) for an SI message transmission opportunity corresponding to a detected SSB.

[0183] In cell-free MIMO deployments, an alternative approach may be preferable: a supercell with many TRPs may not be limited to using a single beam at a time, and simultaneous multi-TRP transmissions can boost the total DL transmit power.

[0184] For example, consider the deployment in FIG. 3 using a legacy cell with two TRPs, each providing two SSB beams in four SSB transmission opportunities. The TRPs may employ analog beamforming, and thus, each TRP can transmit one SSB beam at a time. In this example, TRP0 transmits the first and fourth SSBs, and TRP1 transmits the second and third SSBs. With a multi-TRP cell, joint multi-TRP transmission of SI messages may be feasible. For example, in the first SI message opportunity shown in FIG. 8(a), the PDCCH and PDSCH may be jointly transmitted from TRP0 using the first SSB beam and from TRP1 using the second SSB beam. In the second SI message opportunity shown in FIG. 8(b), the PDCCH and PDSCH may be jointly transmitted from TRP0 using the fourth SSB beam and from TRP1 using the third SSB beam. An example is further shown in Figure 9. The first and second SSBs may be grouped for the first SI message opportunity in the SI window (corresponding to the SI message), and the third and fourth SSBs may be grouped for the second SI message opportunity in the SI window. The WTRU 102 (e.g., UE) may operate with (e.g., assume) the PDCCH and PDSCH during the SI message opportunity QCL'd with the SSBs in the corresponding SSB group.

[0185] Although the diagram may give the impression of having a two-layer PDCCH, it should be noted that the one-port PDCCH may be jointly transmitted using multiple SSB beams in this example (e.g., in an SFN manner). Similarly, the PDSCH carrying the SI message may be a one-port PDSCH jointly transmitted using multiple SSB beams. The PDSCH may be a multi-port PDSCH, with a first antenna port QCL'd with a first set of SSBs in a group, e.g., the first SSB, and a second antenna port QCL'd with a second set of SSBs in the group, e.g., the second SSB. According to an embodiment, the PDSCH may be multi-port, with multiple ports QCL'd with the SSBs in an SSB group.

[0186] According to an embodiment, the SI messages PDCCH and / or PDSCH may be transmitted using a multi-port transmit diversity scheme, such as space-time block coding (STBC) or space-frequency block coding (SFBC). Different ports (or sets of ports) may be QCL'd with different sets of SSBs. For example, in a two-port Alamouti scheme, a first port may be QCL'd with a first SSB (or a first group of SSBs) and a second port may be QCL'd with a second SSB (or a second group of SSBs).

[0187] Different SSB groups to be used in different SI message occasions may be indicated in SIB1.

[0188] For example, SIB1 may indicate an SSB group size. SIB1 may indicate a set of SSBs, e.g., the actually transmitted SSBs. The SSB group may (e.g., then) be determined by the WTRU 102 (e.g., a UE) according to a rule.

[0189] In one example, for an SSB group size of G, and K SSBs or SSBs actually transmitted,

[0190]

number

[0191] The first SSB group may be determined as the first G SSBs (in time or with the lowest SSB index), the second SSB group may be determined by the next G SSBs, etc., until K groups are determined. Note that K may correspond to the maximum number of SSBs (for a frequency band), for example, if the search space for monitoring the PDCCH for other SIBs is the same as the search space for monitoring the PDCCH for SIB1 reception.

[0192] In another example, the first SSB is assigned to the SSB group until all SSBs are assigned to the SSB group.

[0193]

number

[0194] The SSBs are, for example, in order,

[0195]

number

[0196] can be assigned to SSB groups,

[0197]

number

[0198] SSBs may be assigned to the same group, e.g., in the same order, etc. An SSB group may be assigned to, e.g., 0 and

[0199]

number

[0200] , and may be labeled with an SSB group index between .

[0201] In legacy systems, K consecutive PDCCH monitoring opportunities (for other SSB reception) may correspond to K SSBs, e.g., with wraparound from the last SSB to the first SSB in the SI window, where K corresponds to the maximum number of SSBs or the number of SSBs actually transmitted, in various cases. In the above embodiments, K may instead correspond to different SSB group indices, e.g.,

[0202]

number

[0203] There may be consecutive PDCCH monitoring opportunities.

[0204]

number

[0205] The monitoring opportunities may not necessarily be consecutive, for example, every Gth monitoring opportunity may be used instead.

[0206] According to an embodiment, G=K, ie there may be one SSB group containing all K SSBs.

[0207] FIG. 10 illustrates SI message transmission using SSB groups in a supercell with multiple PCIs.

[0208] The method using SSB groups can also be applied to a supercell with SSBs having multiple PCIs. For example, consider a deployment in which four SSBs having a first PCI and four SSBs having a second PCI are transmitted in a supercell. In this example, the same SSB grouping can be performed separately for the first PCI and the second PCI, thereby further reducing resource overhead. In this example, the first SI window corresponding to the first PCI can be different from the second SI window corresponding to the second PCI, for example, due to different SI window configurations in SIB1 for the first PCI and the second PCI.

[0209] An example procedure is shown in FIG. 11. Steps 1101 and 1102 may follow the WTRU (e.g., UE) procedure in FIG. 6. In step 1103, the WTRU 102 (e.g., UE) may determine whether a monitoring opportunity for a PDCCH, which may schedule a PDSCH that may carry an SI message, may be based on an SSB group. If not, the WTRU 102 (e.g., UE) may proceed to step 1104 and determine the PDCCH monitoring opportunity based, e.g., on the index of the detected SSB, e.g., the index (e.g., ordinal position) among the actually transmitted SSBs, as in the legacy procedure. If yes, the WTRU 102 (e.g., UE) may proceed to step 1105 and determine the SSB group of the detected SSB, e.g., determine the PDCCH monitoring opportunity based, e.g., on the SSB group of the detected SSB, as disclosed above. For PDCCH monitoring, the WTRU 102 (e.g., UE) may operate with (e.g., assume) the PDCCH QCL'd with all SSBs in the SSB group of the detected SSB. According to an embodiment, the WTRU 102 (e.g., UE) may operate with (e.g., assume) the PDCCH QCL'd with (e.g., only) the detected SSB. For PDSCH reception, the WTRU 102 (e.g., UE) may operate with (e.g., assume) it QCL'd with the SSBs in the SSB group or only with the detected SSB.

[0210] Anchor PCI and SSB group combination

[0211] Enhanced acquisition of other SSBs using the anchor PCI may be combined with the SSB group. Consider a scenario in which four SSBs with a first PCI may be transmitted in a super-cell, e.g., from TRP0 and TRP1, and four SSBs with a second PCI may be transmitted in a super-cell, e.g., from TRP2 and TRP3. In the first transmission opportunity, the four TRPs may jointly transmit the PDCCH and PDSCH, each using the first SSB beam, as shown in Figure 12(a). In the second transmission opportunity, the four TRPs may jointly transmit the PDCCH and PDSCH, each using the second SSB beam, as shown in Figure 12(b).

[0212] Joint multi-TRP transmission of SI messages using an anchor PCI and an SSB group is shown in FIG. 13. PDCCH monitoring opportunities for the SSB group may be configured in SIB1 to overlap for the first PCI and the second PCI. A WTRU 102 (e.g., a UE) that detects an SSB with the second PCI may use the first PCI as the anchor PCI when (e.g., when) receiving a PDCCH and / or a scheduled PDSCH. As an example, consider a first WTRU (e.g., a UE) that detects a first SSB with the first PCI, a second WTRU (e.g., a UE) that detects a second SSB with the first PCI, a third WTRU (e.g., a UE) that detects the first SSB with the second PCI, and a fourth WTRU (e.g., a UE) that detects the second SSB with the second PCI. The first WTRU and the second WTRU (e.g., UE) may have received SIB1 for the first PCI, and the third WTRU and the fourth WTRU (e.g., UE) may have received SIB1 for the second PCI. However, all four WTRUs 102 (e.g., UEs) may receive the same PDCCH in the first PDCCH monitoring opportunity and (e.g., then) receive the same PDSCH, which may be scheduled by the PDCCH. The SI messages (PDCCH and / or PDSCH) may be jointly transmitted with SSB beams corresponding to the four SSBs detected by the four WTRUs 102 (e.g., UEs).

[0213] An example procedure is shown in FIG. 14. Steps 1401 and 1402 may follow the WTRU (e.g., UE) procedure in FIG. 6. In step 1403, the WTRU 102 (e.g., UE) determines whether a monitoring opportunity for a PDCCH, which may schedule a PDSCH that may carry an SI message, may be based on an SSB group and whether reception of the SI message is based on an anchor PCI. If not, the WTRU 102 (e.g., UE) may proceed to step 1404 and may determine a PDCCH monitoring opportunity based on an index of the detected SSB and may receive the SI message using the first PCI. If yes, the WTRU 102 (e.g., UE) may proceed to step 1405 and may determine an SSB group of the detected SSB, e.g., may determine a PDCCH monitoring opportunity based on the SSB group of the detected SSB as disclosed above, and may determine that the SI message may be received using the anchor PCI.

[0214] Legacy WTRU (e.g., UE) Operational Considerations

[0215] A legacy WTRU (e.g., UE) in the super cell may be able to detect the SSB and may acquire the corresponding SIB1 based on the legacy procedure. With the enhancements described above, the legacy WTRU (e.g., UE) may not be able to acquire other SIBs. It may be preferable to indicate that the corresponding SI message cannot be broadcast in the cell using legacy signaling, for example, by setting the corresponding broadcast status as “notBroadcasting” in SchedulingInfo in SIB1. A third state, for example, “Broadcasting,” “notBroadcasting,” and a new “enhancedBroadcasting” may be introduced to indicate to an enhanced WTRU (e.g., UE) that the SI message can be broadcast using the enhanced scheme. An additional flag may be introduced to indicate to an enhanced WTRU (e.g., UE) that the SI message can be broadcast using the enhancement, even if the legacy broadcast status is “notBroadcasting.” However, the SIB1 corresponding to the anchor PCI may indicate the SI message as broadcasting.

[0216] According to an embodiment, a legacy WTRU (e.g., UE) may request transmission of other SIBs on the super cell, which may then be transmitted according to legacy procedures in the super cell. However, this may be an attractive approach when (e.g., only) there may be (e.g., only) a few legacy WTRUs (e.g., UEs) in the network. If legacy WTRUs (e.g., UEs) are still common, it may be better to indicate the super cell as forbidden (to legacy WTRUs (e.g., UEs)), for example, in the MIB and / or in SIB1. If so, a new forbidden indication for enhanced WTRUs (e.g., UEs) may be added to SIB1. Furthermore, enhanced WTRUs (e.g., UEs) may ignore the legacy forbidden indication in the MIB. A legacy WTRU (e.g., UE) may access the super cell, or rather the legacy cell corresponding to the PCI in the super cell, as an SCell or PSCell, because the WTRU (e.g., UE) may not (e.g., need not) perform initial access on the super cell and may receive other SIBs for the super cell through dedicated signaling. The SSBs in the super cell may not be extended, and therefore they may be used in the SCell or PSCell for legacy procedures, such as synchronization and beam management.

[0217] For reference, an exemplary procedure is described below and may include any of the following steps: The WTRU 102 (eg, a UE) may detect an SSB with a first PCI that includes a PBCH. The WTRU 102 (eg, a UE) may receive SIB1 based on the configuration in the PBCH in the detected SSB. SIB1 may indicate to the WTRU 102 (eg, a UE) that SI messages may be received using an anchor PCI different from the first PCI. The WTRU 102 (e.g., UE) may use the detected SSB with the first PCI as a QCL source and otherwise use the anchor PCI for PDCCH and PDSCH reception to receive the PDCCH and corresponding scheduled PDSCH, which may carry an SI message.

[0218] FIG. 15 shows an example of a method 1500 implemented by a WTRU.

[0219] Referring to FIG. 15, a representative method 1500 may include, at block 1510, detecting a first signal transporting an SSB associated with a first PCI. At block 1520, the representative method 1500 may include decoding a physical broadcast channel payload of the SSB, the PBCH payload including information indicative of a master information block configuration. At block 1530, the representative method 1500 may include receiving a second signal transporting SIB1 using the master information block configuration. At block 1540, the representative method 1500 may include determining information indicative of a second PCI based on SIB1. At block 1550, the representative method 1500 may include receiving a system information message using the second PCI.

[0220] According to an embodiment, the second PCI is different from the first PCI.

[0221] According to an embodiment, a second PCI indication is included in SIB1.

[0222] According to an embodiment, the SSB group for SI message reception indication is included in SIB1.

[0223] According to an embodiment, the detected SSB is in an SSB group.

[0224] According to an embodiment, the exemplary method 1500 may include receiving an SI message on time-frequency resources associated with SSBs in an SSB group.

[0225] According to an embodiment, the SI messages are quasi-collocated with the SSBs in the SSB group.

[0226] FIG. 16 shows an example of a method 1600 implemented by a WTRU.

[0227] Referring to FIG. 16, a representative method 1600 may include, at block 1610, receiving an SSB based on a first PCI. At block 1620, the representative method 1600 may include decoding a payload of the SSB, the payload including information indicating a resource set and a search space configuration. At block 1630, the representative method 1600 may include receiving a SIB based on the first PCI and the resource set and the search space configuration. At block 1640, the representative method 1600 may include determining information indicating a second PCI based on the SIB, the second PCI being different from the first PCI. At block 1650, the representative method 1600 may include receiving a scheduled transmission including system information based on the second PCI, the scheduled transmission being QCL'd with the SSB.

[0228] According to an embodiment, decoding the payload of the SSB includes decoding a physical broadcast channel transmission payload.

[0229] According to an embodiment, the scheduled transmission is included in a physical shared channel transmission.

[0230] According to an embodiment, receiving a scheduled transmission includes receiving a physical downlink control channel transmission that schedules a physical shared channel transmission.

[0231] According to an embodiment, the physical shared channel transmission is received based on the second PCI.

[0232] According to an embodiment, the SIB includes information indicating one or more sets of SSBs for receiving system information messages.

[0233] According to an embodiment, the received SSB is included in a set of SSBs out of one or more sets of SSBs.

[0234] According to an embodiment, the exemplary method 1600 may include receiving a system information message on time-frequency resources associated with a set of SSBs.

[0235] According to an embodiment, the scheduled transmissions are quasi-colocated with a set of SSBs.

[0236] While features and elements are provided above in particular combinations, those skilled in the art will appreciate that each feature or element can be used alone or in any combination with the other features and elements. The present disclosure should not be limited in terms of the specific embodiments described in this application, which are intended as illustrations of various aspects. As will be apparent to those skilled in the art, many modifications and variations can be made without departing from the spirit and scope thereof. No element, act, or instruction used in the description of the present application should be construed as critical or essential to the invention unless explicitly provided as such. Functionally equivalent methods and apparatuses within the scope of the present disclosure, in addition to those enumerated herein, will be apparent to those skilled in the art from the above description. Such modifications and variations are intended to fall within the scope of the appended claims. The present disclosure should be limited only by the terms of the appended claims, along with the full range of equivalents to which such claims are entitled. It is understood that the present disclosure is not limited to a particular method or system.

[0237] The above embodiments are described, for simplicity, with reference to the terminology and structure of wireless communication enabled devices (e.g., radio wave emitters and receivers). However, the described embodiments are not limited to these systems and may be applied to other systems that use other forms of electromagnetic waves, or non-electromagnetic waves such as sound waves.

[0238] It should also be understood that the terminology used herein is for purposes of describing particular embodiments only and is not intended to be limiting. As used herein, the term “video” or “image” may refer to either a snapshot, a single image, and / or multiple images displayed over a time base. As another example, when referred to herein, the term “user equipment” and its abbreviation “UE,” “remote,” and / or the term “head-mounted display” or its abbreviation “HMD” may mean or include (i) a wireless transmit and / or receive unit (WTRU), (ii) any of several embodiments of a WTRU, (iii) a wireless-enabled and / or wired-enabled (e.g., tetherable) device configured with, among other things, some or all of the structure and functionality of a WTRU, (iii) a wireless-enabled and / or wired-enabled device configured with less than all of the structure and functionality of a WTRU, or (iv) the like. Details of an example WTRU that may represent any WTRU enumerated herein are provided herein with respect to FIGS. 1A-1D . As another example, various disclosed embodiments herein above and below are described as utilizing a head-mounted display. Those skilled in the art will recognize that devices other than head-mounted displays may be utilized, and that some or all of the present disclosure and various disclosed embodiments may be modified accordingly without undue experimentation. Examples of such other devices may include drones or other devices configured to stream information to provide an adapted reality experience.

[0239] Furthermore, the methods provided herein may be implemented in a computer program, software, or firmware embodied in a computer-readable medium for execution by a computer or processor. Examples of computer-readable media include electronic signals (transmitted via wired or wireless connections) and computer-readable storage media. Examples of computer-readable storage media include, but are not limited to, read-only memory (ROM), random-access memory (RAM), registers, cache memory, semiconductor memory devices, magnetic media such as internal hard disks and removable disks, magneto-optical media, and optical media such as CD-ROM disks and digital versatile disks (DVDs). A processor in association with software may be used to implement a radio frequency transceiver for use in a WTRU, UE, terminal, base station, RNC, or any host computer.

[0240] Modifications to the methods, apparatus, and systems provided above are possible without departing from the scope of the present invention. In view of the wide variety of embodiments that may be applied, it should be understood that the illustrated embodiments are merely examples and should not be taken as limiting the scope of the following claims. For example, the embodiments provided herein include handheld devices that may include or be utilized with any suitable voltage source, such as a battery, that provides any suitable voltage.

[0241] Furthermore, in the embodiments provided above, reference is made to processing platforms, computing systems, controllers, and other devices that include processors. These devices may include at least one central processing unit ("CPU") and memory. In accordance with the practices of those skilled in the art of computer programming, references to acts and symbolic representations of operations or instructions may be performed by various CPUs and memories. Such acts and operations or instructions may be referred to as being "executed," "computer-executed," or "CPU-executed."

[0242] Those skilled in the art will appreciate that the acts and symbolically represented operations or instructions include the manipulation of electrical signals by a CPU. The electrical system represents the data bits, which cause the transformation or reduction of the resulting electrical signals and the maintenance of the data bits in memory locations in a memory system, thereby allowing the operation of the CPU, as well as other processing of the signals, to be reconfigured or otherwise altered. The memory locations where the data bits are maintained are physical locations that have particular electrical, magnetic, optical, or organic properties that correspond to or represent the data bits. It should be understood that embodiments are not limited to the above-mentioned platforms or CPUs, and that other platforms and CPUs can support the provided methods.

[0243] The data bits may also be maintained on a computer-readable medium, including magnetic disks, optical disks, and any other volatile (e.g., random access memory (RAM)) or non-volatile (e.g., read-only memory (ROM)) mass storage system readable by a CPU. The computer-readable medium may include computer-readable media that reside exclusively on a processing system or that are distributed, cooperating, or interconnected among multiple interconnected processing systems, which may be local or remote to the processing system. It should be understood that the embodiments are not limited to the memories described above, and that other platforms and memories may support the provided methods.

[0244] In an example embodiment, any of the operations, processes, etc. described herein may be implemented as computer-readable instructions stored on a computer-readable medium, which may be executed by a processor of a mobile unit, a network element, and / or any other computing device.

[0245] Little distinction remains between hardware and software implementations of aspects of the system. The use of hardware or software is generally (but not always, in that in certain contexts, the choice between hardware and software can be important) a design choice representing a cost vs. efficiency trade-off. There may be various means (e.g., hardware, software, and / or firmware) by which the processes and / or systems and / or other techniques described herein may be achieved, and the preferred means may vary depending on the context in which the processes and / or systems and / or other techniques are deployed. For example, if an implementer determines that speed and accuracy are paramount, the implementer may select a primarily hardware and / or firmware means. If flexibility is paramount, the implementer may select a primarily software implementation. Alternatively, the implementer may select some combination of hardware, software, and / or firmware.

[0246] The above detailed description sets forth various embodiments of devices and / or processes through the use of block diagrams, flowcharts, and / or examples. To the extent that such block diagrams, flowcharts, and / or examples include one or more functions and / or operations, those skilled in the art will appreciate that each function and / or operation within such block diagrams, flowcharts, or examples may be individually and / or collectively implemented by a wide range of hardware, software, firmware, or substantially any combination thereof. In one embodiment, portions of the subject matter described herein may be implemented via an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a digital signal processor (DSP), and / or other integrated format. However, those skilled in the art will recognize that some aspects of the embodiments disclosed herein may equivalently be implemented, in whole or in part, as one or more computer programs running on one or more computers (e.g., as one or more programs running on one or more computer systems), as one or more programs running on one or more processors (e.g., as one or more programs running on one or more microprocessors), as firmware, or as substantially any combination thereof, in integrated circuits, and that designing circuitry and / or writing code for software and / or firmware is well within the skill of those skilled in the art in light of this disclosure. Furthermore, those skilled in the art will appreciate that the subject matter mechanisms described herein may be distributed as program products in various forms, and that exemplary embodiments of the subject matter described herein apply regardless of the particular type of signal-bearing medium used to actually effect the distribution.Examples of signal-bearing media include, but are not limited to, recordable-type media such as floppy disks, hard disk drives, CDs, DVDs, digital tape, computer memory, and transmission-type media such as digital and / or analog communications media (e.g., fiber optic cables, wave guides, wired communications links, wireless communications links, etc.).

[0247] Those skilled in the art will recognize that it is common within the art to describe devices and / or processes in the manner described herein and then integrate such described devices and / or processes into a data processing system using engineering practices. That is, at least a portion of the devices and / or processes described herein can be integrated into a data processing system through a reasonable amount of experimentation. Those skilled in the art will recognize that a typical data processing system can generally include one or more of the following: a system unit housing; a video display device; memory, such as volatile and non-volatile memory; a processor, such as a microprocessor and a digital signal processor; computing entities, such as an operating system, drivers, a graphical user interface, and application programs; one or more interaction devices, such as a touchpad or screen; and / or a control system, including feedback loops and control motors (e.g., feedback for sensing position and / or velocity, control motors for moving and / or adjusting components and / or quantities). A typical data processing system can be implemented utilizing any suitable commercially available components, such as those typically found in data computing / communications and / or network computing / communications systems.

[0248] The subject matter described herein may depict different components contained within or connected with different other components. It should be understood that such depicted architectures are merely examples, and that in fact many other architectures that achieve the same functionality may be implemented. In a conceptual sense, any arrangement of components to achieve the same functionality is effectively “associated” such that the desired functionality may be achieved. Thus, any two components combined herein to achieve a particular functionality may be considered to be “associated” with each other such that the desired functionality is achieved, regardless of the architecture or intermediate components. Similarly, any two components so associated may also be considered to be “operably connected” or “operably coupled” with each other to achieve the desired functionality, and any two components capable of being so associated may also be considered to be “operably couplable” with each other to achieve the desired functionality. Specific examples of what is operably couplable include, but are not limited to, physically matable and / or physically interacting components, wirelessly interacting and / or wirelessly interacting components, and / or logically interacting and / or logically interacting components.

[0249] With respect to the use of virtually any plural and / or singular term herein, those skilled in the art can translate from the plural to the singular and / or from the singular to the plural as appropriate to the context and / or application. Various singular / plural permutations may be expressly set forth herein for clarity.

[0250] Those skilled in the art will understand that, generally, the terminology used herein, and particularly the terms used in the appended claims (e.g., the body of the appended claims), are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including, but not limited to,” the term “having” should be interpreted as “having at least,” the term “including” should be interpreted as “including, but not limited to,” etc.). Those skilled in the art will further understand that where a specific number of introduced claim recitations is intended, such intention will be expressly recited in the claim; in the absence of such recitation, no such intention exists. For example, where only one item is intended, the term “single” or similar language may be used. As an aid to understanding, the following appended claims and / or description herein may include the use of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed as implying that introducing a claim recitation with the indefinite article "a" or "an" limits any particular claim containing such an introduced claim recitation to embodiments containing only one such recitation, even if the same claim also includes the introductory phrase "one or more" or "at least one" and an indefinite article such as "a" or "an" (e.g., "a" and / or "an" should be construed to mean "at least one" or "one or more"). The same applies to the use of definite articles used to introduce claim recitations. Furthermore, those skilled in the art will recognize that even if a specific number of introduced claim recitations is explicitly recited, such recitation should be construed to mean at least the recited number (e.g., the mere recitation of "two recitations" without other modifiers means at least two recitations, or more than two recitations).Furthermore, in instances where a convention similar to "at least one of A, B, and C, etc." is used, such a configuration is generally intended in the sense that one of ordinary skill in the art would understand the convention (e.g., "a system having at least one of A, B, and C" includes, but is not limited to, systems having A only, B only, C only, A and B together, A and C together, B and C together, and / or A, B, and C together, etc.). In instances where a convention similar to "at least one of A, B, or C, etc." is used, such a configuration is generally intended in the sense that one of ordinary skill in the art would understand the convention (e.g., "a system having at least one of A, B, or C" includes, but is not limited to, systems having A only, B only, C only, A and B together, A and C together, B and C together, and / or A, B, and C together, etc.). Those skilled in the art will further appreciate that virtually any disjunctive word and / or phrase presenting two or more alternative terms, whether in the specification, claims, or drawings, should be understood to contemplate the possibility of including one of those terms, either of those terms, or both terms. For example, the phrase "A or B" will be understood to include the possibilities of "A" or "B" or "A and B." Furthermore, as used herein, the term "any of," followed by a listing of multiple items and / or multiple categories of items, is intended to include "any of," "any combination of," "any multiple of," and / or "any combination of multiples of" the items and / or categories of items, individually or in conjunction with other items and / or other categories of items. Moreover, as used herein, the term "set" is intended to include any number of items, including zero. Additionally, as used herein, the term "number" is intended to include any number, including zero. Also, as used herein, the term "multiple" is intended to be synonymous with "a plurality."

[0251] Furthermore, those skilled in the art will recognize that when features or aspects of the disclosure are described in terms of a Markush group, the disclosure is also thereby described in terms of any individual members or subgroups of members of the Markush group.

[0252] As will be understood by those skilled in the art, for all purposes, including with respect to providing a specification, all ranges disclosed herein encompass any and all possible subranges and combinations of those subranges. Any recited range can be readily recognized as fully descriptive and allowing for that same range to be divided into at least two equal parts, one-third, one-quarter, one-fifth, one-tenth, etc. As a non-limiting example, each range described herein can be readily divided into a lower third, middle third, and upper third, etc. Also, as will be understood by those skilled in the art, all terms such as "at most," "at least," "greater than," and "less than" are inclusive of the recited number and refer to ranges that may be subsequently divided into subranges, as described above. Finally, as will be understood by those skilled in the art, a range includes each individual member. Thus, for example, a group having 1 to 3 cells refers to a group having 1, 2, or 3 cells. Similarly, a group having 1 to 5 cells refers to a group having 1, 2, 3, 4, or 5 cells, and so on.

[0253] Furthermore, the claims should not be read as limited to the provided order or elements unless stated to that effect. In addition, the use of the term "means for" in any claim is intended to implement 35 U.S.C. § 112, paragraph 6 or means-plus-function claim format, and any claim without the term "means for" is not so intended.

Claims

1. 1. A method implemented by a wireless transmit / receive unit (WTRU), comprising: receiving a synchronization signal block (SSB) based on a first physical cell identity (PCI); Decoding a payload of the SSB, the payload including information indicating a resource set and a search space configuration; receiving a system information block (SIB) based on the first PCI and the resource set and search space configuration; determining, based on the SIB, information indicating a second PCI, wherein the second PCI is different from the first PCI; and receiving a scheduled transmission including system information based on the second PCI, the scheduled transmission being quasi-co-located with the SSB; A method comprising:

2. The method of claim 2 , wherein decoding the SSB payload includes decoding a physical broadcast channel transmission payload.

3. The method of claim 1 , wherein the scheduled transmission is comprised in a physical shared channel transmission.

4. The method of claim 3 , wherein receiving the scheduled transmission comprises receiving a physical downlink control channel transmission that schedules the physical shared channel transmission.

5. The method of claim 4 , wherein the physical shared channel transmission is received based on the second PCI.

6. The method according to claim 1 , wherein the SIB includes information indicating one or more sets of SSBs for receiving system information messages.

7. The method of claim 6 , wherein the received SSB is included in a set of SSBs of one or more sets of SSBs.

8. 8. The method of claim 7, comprising receiving a system information message on time-frequency resources associated with the set of SSBs.

9. The method of claim 8 , wherein the scheduled transmissions are quasi-colocated with the set of SSBs.

10. A wireless transmit / receive unit (WTRU) comprising circuitry including a transmitter, a receiver, a processor, and a memory, receiving a synchronization signal block (SSB) based on a first physical cell identity (PCI); Decoding a payload of the SSB, the payload including information indicating a resource set and a search space configuration; receiving a system information block (SIB) based on the first PCI and the resource set and search space configuration; determining information indicating a second PCI based on the SIB, the second PCI being different from the first PCI; receiving a scheduled transmission including system information based on the second PCI, the scheduled transmission being quasi-co-located with the SSB; The WTRU is configured to:

11. The WTRU of claim 10 , wherein the WTRU configured to decode the payload of the SSB comprises the WTRU configured to decode a physical broadcast channel transmission payload.

12. The WTRU of claim 10, wherein the scheduled transmission is included in a physical shared channel transmission.

13. 13. The WTRU of claim 12, wherein the WTRU configured to receive the scheduled transmission comprises the WTRU configured to receive a physical downlink control channel transmission that schedules the physical shared channel transmission.

14. The WTRU of claim 13 , wherein the physical shared channel transmission is received based on the second PCI.

15. The WTRU of claim 10 , wherein the SIB includes information indicating one or more sets of SSBs for receiving system information messages.

16. The WTRU of claim 15, wherein the received SSB is included in a set of SSBs of one or more sets of SSBs.

17. The WTRU of claim 16, configured to receive system information messages on time-frequency resources associated with the set of SSBs.

18. The WTRU of claim 17, wherein the scheduled transmissions are quasi-co-located with the set of SSBs.

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