GROUP-COMMON PHYSICAL DOWNLINK CONTROL CHANNELS FOR WIRELESS

COMMUNICATION

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application Serial No.

62/585,904 filed November 14, 2017, U.S. Provisional Application Serial No. 62/555,906 filed September 8, 2017, and U.S. Provisional Application Serial No. 62/519,783 filed June 14, 2017.

BACKGROUND

[0002] Fifth generation (5G) wireless systems and networks may utilize new frames, multiplexing, and mobility procedures to provide enhanced mobile broadband (eMBB), ultra-reliable low latency communication (URLLC), massive Machine Type Communication (mMTC), etc. for a new radio (NR) access technology. A common physical downlink control channel (PDCCH), physical control format indicator channel (PCFICH), and other channels may be utilized for transmitting common signaling needed for scheduling downlink data or detection of WTRU-specific PDCCH. Efficiently communicating common signaling is desired to improve performance of downlink and uplink URLLC traffic or 5G traffic. It is especially desirable for traffic that may be sporadic, infrequent, bursty, use small payloads, unscheduled, or unpredictable.

SUMMARY

[0003] A group-common physical downlink control channel (PDCCH) may be configured by wireless transmit/receive units (WTRUs) within a cell or beam. The group-common PDCCH may be utilized with a common PDCCH or independently. A group-common PDCCH may also be assigned to a group or cluster of WTRUs and multiple group-common PDCCH channels may be communicated or assigned to WTRUs. A group-common PDCCH may be monitored at different rates.

BRIEF DESCRIPTION OF THE DRAWINGS

[0004] A more detailed understanding may be had from the following description, given by way of example in conjunction with the accompanying drawings, wherein like reference numerals in the figures indicate like elements, and wherein:

[0005] FIG. 1 A is a system diagram illustrating an example of a communications system in which one or more disclosed embodiments may be implemented;

[0006] FIG. 1 B is a system diagram illustrating an example of a wireless transmit/receive unit (WTRU) that may be used within the communications system illustrated in FIG. 1A according to an embodiment; [0007] FIG. 1 C is a system diagram illustrating an example of a radio access network

(RAN) and an exemplary core network (CN) that may be used within the communications system illustrated in FIG. 1A according to an embodiment;

[0008] FIG. 1 D is a system diagram illustrating a further example of a RAN and a further example of a CN that may be used within the communications system illustrated in FIG. 1A according to an embodiment;

[0009] FIG. 2 is a diagram of an exemplary resource element group (REG) structure for the group-common physical downlink control channel (PDCCH);

[0010] FIG. 3 is a diagram of an exemplary structure utilizing REGs and REG bundles for a group-common PDCCH;

[0011] FIG. 4 is a diagram of an example of utilizing REG, REG bundles, and control channel elements (CCEs) and a forward error correction (FEC) and a cyclic redundancy code (CRC) in relation to a PDCCH;

[0012] FIG. 5 is a diagram of an example of mapping of group-common PDCCH to the first

OFDM symbol of a control resource set (CORESET);

[0013] FIG. 6 is an exemplary mapping of a group-Identification (ID) to an indicator transmitted in a group-common PDCCH;

[0014] FIG. 7 is an exemplary mapping of a group-ID to an implicit indicator in the downlink control information (DCI);

[0015] FIG. 8 is an example of a group-ID indication using a block-wise circular shifted scrambling sequence;

[0016] FIG. 9 is a diagram of an example of a dynamic group-common PDCCH with three types of information;

[0017] FIG. 10 is a diagram of an example of a dynamic group-common PDCCH with a

DCI index; and

[0018] FIG. 11 is a flowchart of an example WTRU procedure for group-common PDCCH reception.

DETAILED DESCRIPTION

[0019] FIG. 1A is a diagram illustrating an example communications system 100 in which one or more disclosed embodiments may be implemented. The communications system 100 may be a multiple access system that provides content, such as voice, data, video, messaging, broadcast, etc., to multiple wireless users. The communications system 100 may enable multiple wireless users to access such content through the sharing of system resources, including wireless bandwidth. For example, the communications 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 unique-word discrete Fourier transform spread orthogonal frequency division multiplexing (ZT UW DTS-s OFDM), unique word OFDM (UW-OFDM), resource block-filtered OFDM, filter bank multicarrier (FBMC), and the like.

[0020] As shown in FIG. 1A, the communications system 100 may include wireless transmit/receive units (WTRUs) 102a, 102b, 102c, 102d, a radio access network (RAN) 104, a core network (CN) 106, a public switched telephone network (PSTN) 108, the Internet 110, and other networks 112, though it will be appreciated that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, and/or network elements. Each of the 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 a "STA", may be configured to transmit and/or receive wireless signals and may include a user equipment (UE), a mobile station, a fixed or mobile subscriber unit, a subscription-based unit, a pager, a cellular telephone, 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 (loT) device, a watch or other wearable, a head-mounted display (HMD), a vehicle, a drone, a medical device and applications (e.g., remote surgery), an industrial device and applications (e.g., a robot and/or other wireless devices operating in an industrial and/or an automated processing chain contexts), a consumer electronics device, a device operating on commercial and/or industrial wireless networks, and the like. Any of the WTRUs 102a, 102b, 102c and 102d may be interchangeably referred to as a UE.

[0021] 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 communication networks, such as the CN 106, the Internet 110, and/or the other networks 112. By way of example, the base stations 114a, 114b may be a base transceiver station (BTS), a Node-B, an eNode B, a Home Node B, a Home eNode B, a next generation node b (gNB), a new radio (NR) NodeB, a site controller, an access point (AP), a wireless router, and the like. While the base stations 114a, 114b are each depicted 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.

[0022] The base station 114a may be part of the RAN 104, 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 the base station 114b may be configured to transmit and/or receive wireless signals on one or more carrier frequencies, which may be referred to as a cell (not shown). These frequencies may be in licensed spectrum, unlicensed spectrum, or a combination of licensed and unlicensed spectrum. A cell may provide coverage for a wireless service to a specific geographical area that may be relatively fixed or that may change over time. The cell may further be 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 an embodiment, the base station 114a may employ multiple-input multiple output (MIMO) technology and may utilize multiple transceivers for each sector of the cell. For example, beamforming may be used to transmit and/or receive signals in desired spatial directions.

[0023] 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).

[0024] More specifically, as noted above, the communications 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, and the like. For example, the base station 114a in the RAN 104 and the WTRUs 102a, 102b, 102c 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 (DL) Packet Access (HSDPA) and/or High-Speed Uplink (UL) Packet Access (HSUPA).

[0025] In an 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).

[0026] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as NR Radio Access , which may establish the air interface 116 using New Radio (NR).

[0027] In an 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 implement LTE radio access and NR radio access together, for instance using dual connectivity (DC) principles. Thus, the air interface utilized by WTRUs 102a, 102b, 102c may be characterized by multiple types of radio access technologies and/or communications sent to/from multiple types of base stations (e.g., an eNB and a gNB).

[0028] In other embodiments, the base station 114a and the WTRUs 102a, 102b, 102c may implement radio technologies such as Institute of Electrical and Electronics Engineers (IEEE) 802.11 (i.e., Wireless Fidelity (WiFi), 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), and the like.

[0029] The base station 114b in FIG. 1A may be a wireless router, Home Node B, Home eNode B, or access point, for example, and may utilize any suitable RAT for facilitating wireless connectivity in a localized area, such as a place of business, a home, a vehicle, a campus, an industrial facility, an air corridor (e.g., for use by drones), a roadway, and the like. 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 an 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 yet another 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 a picocell or femtocell. As shown in FIG. 1A, the base station 114b may have a direct connection to the Internet 110. Thus, the base station 114b may not be required to access the Internet 110 via the CN 106.

[0030] The RAN 104 may be in communication with the CN 106, which may be any type of network configured to provide voice, data, applications, and/or voice over internet protocol (VoIP) services to one or more of the WTRUs 102a, 102b, 102c, 102d. The data may have varying quality of service (QoS) requirements, such as differing throughput requirements, latency requirements, error tolerance requirements, reliability requirements, data throughput requirements, mobility requirements, and the like. The CN 106 may provide call control, billing services, mobile location- based services, pre-paid 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 and/or the CN 106 may be in direct or indirect communication with other RANs that employ the same RAT as the RAN 104 or a different RAT. For example, in addition to being connected to the RAN 104, which may be utilizing a NR radio technology, the CN 106 may also be in communication with another RAN (not shown) employing a GSM, UMTS, CDMA 2000, WiMAX, E-UTRA, or WiFi radio technology.

[0031] The CN 106 may also serve as a gateway for the WTRUs 102a, 102b, 102c, 102d to access the PSTN 108, the Internet 110, and/or the other networks 112. The PSTN 108 may include circuit-switched telephone networks that provide plain old telephone service (POTS). The Internet 110 may include a global system of interconnected computer networks and devices that use common communication protocols, such as the transmission control protocol (TCP), user datagram protocol (UDP) and/or the internet protocol (IP) in the TCP/IP internet protocol suite. The other networks 112 may include wired and/or wireless communication networks owned and/or operated by other service providers. For example, the other networks 112 may include another CN connected to one or more RANs, which may employ the same RAT as the RAN 104 or a different RAT.

[0032] 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 the base station 114a, which may employ a cellular-based radio technology, and with the base station 114b, which may employ an IEEE 802 radio technology.

[0033] FIG. 1 B is a system diagram illustrating an example WTRU 102. As shown in FIG.

1 B, the WTRU 102 may include a processor 118, a transceiver 120, a transmit/receive element 122, a speaker/microphone 124, a keypad 126, a display/touchpad 128, non-removable memory 130, removable memory 132, a power source 134, a global positioning system (GPS) chipset 136, and/or other peripherals 138, among others. It will be appreciated that the WTRU 102 may include any subcombination of the foregoing elements while remaining consistent with an embodiment.

[0034] The processor 118 may be a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors in association with a DSP core, a controller, a microcontroller, Application Specific Integrated Circuits (ASICs), Field Programmable Gate Array (FPGA) circuits, any other type of integrated circuit (IC), a state machine, and the like. 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. 1 B 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 integrated together in an electronic package or chip. [0035] The transmit/receive element 122 may be configured to transmit signals to, or receive signals from, a base station (e.g., the 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 an 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 yet another 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.

[0036] Although the transmit/receive element 122 is depicted in FIG. 1 B as a single element, the WTRU 102 may include any number of transmit/receive elements 122. More specifically, 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.

[0037] The transceiver 120 may be configured to modulate the signals that are to be transmitted by the transmit/receive element 122 and to demodulate the signals that are received by the transmit/receive element 122. As noted above, the WTRU 102 may have multi-mode capabilities. Thus, the transceiver 120 may include multiple transceivers for enabling the WTRU 102 to communicate via multiple RATs, such as NR and IEEE 802.11 , for example.

[0038] The processor 118 of the WTRU 102 may be coupled to, and may receive user input data from, the speaker/microphone 124, the keypad 126, and/or the display/touchpad 128 (e.g., a liquid crystal display (LCD) display unit or 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. In addition, the processor 118 may access information from, and store data in, any type of suitable memory, such as the non-removable memory 130 and/or the 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, and the like. 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 a home computer (not shown).

[0039] The processor 118 may receive power from the power source 134, and may be configured to distribute and/or control the power to the 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 cell batteries (e.g., nickel-cadmium (NiCd), nickel-zinc (NiZn), nickel metal hydride (NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, and the like.

[0040] The processor 118 may also be coupled to the GPS chipset 136, which may be configured to provide location information (e.g., longitude and latitude) regarding the current location of the WTRU 102. In addition to, or in lieu of, the information from the GPS chipset 136, the WTRU 102 may receive location information over the air interface 116 from a base station (e.g., base stations 114a, 114b) and/or determine its location based on the timing of the signals being received from two or more nearby base stations. It will be appreciated that the WTRU 102 may acquire location information by way of any suitable location-determination method while remaining consistent with an embodiment.

[0041] The processor 118 may further be coupled to other peripherals 138, which may include one or more software and/or hardware modules that provide additional features, functionality and/or wired or wireless connectivity. For example, the peripherals 138 may include an accelerometer, an e-compass, a satellite transceiver, a digital camera (for photographs and/or video), 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, and the like. The peripherals 138 may include one or more sensors. The sensors 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, a humidity sensor, or the like.

[0042] The WTRU 102 may include a full duplex radio for which transmission and reception of some or all of the signals (e.g., associated with particular subframes for both the UL (e.g., for transmission) and downlink (e.g., for reception) may be concurrent, simultaneous, or the like. The full duplex radio may include an interference management unit to reduce and or substantially eliminate self-interference via either hardware (e.g., a choke) or signal processing via a processor (e.g., a separate processor (not shown) or via processor 118). In an embodiment, the WTRU 102 may include a half-duplex radio for which transmission and reception of some or all of the signals (e.g., associated with particular subframes for either the UL (e.g., for transmission) or the downlink (e.g., for reception)).

[0043] FIG. 1 C is a system diagram illustrating the RAN 104 and the CN 106 according to an embodiment. As noted above, the RAN 104 may employ an E-UTRA radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 104 may also be in communication with the CN 106.

[0044] The RAN 104 may include eNode-Bs 160a, 160b, 160c, though it will be appreciated that the RAN 104 may include any number of eNode-Bs while remaining consistent with an embodiment. The eNode-Bs 160a, 160b, 160c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the eNode-Bs 160a, 160b, 160c may implement MIMO technology. Thus, the eNode-B 160a, for example, may use multiple antennas to transmit wireless signals to, and/or receive wireless signals from, the WTRU 102a.

[0045] Each of the eNode-Bs 160a, 160b, 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 UL and/or DL, and the like. As shown in FIG. 1C, the eNode-Bs 160a, 160b, 160c may communicate with one another over an X2 interface.

[0046] The CN 106 shown in FIG. 1 C may include a mobility management entity (MME)

162, a serving gateway (SGW) 164, and a packet data network (PDN) gateway (or PGW) 166. While each of the foregoing elements is depicted as part of the CN 106, it will be appreciated that any of these elements may be owned and/or operated by an entity other than the CN operator.

[0047] The MME 162 may be connected to each of the eNode-Bs 162a, 162b, 162c in the

RAN 104 via an S1 interface and may serve as a control node. For example, the MME 162 may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, bearer activation/deactivation, selecting a particular serving gateway during an initial attach of the WTRUs 102a, 102b, 102c, and the like. The MME 162 may 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.

[0048] The SGW 164 may be connected to each of the eNode Bs 160a, 160b, 160c in the

RAN 104 via the 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 user planes during inter-eNode B handovers, triggering paging when DL data is available for the WTRUs 102a, 102b, 102c, managing and storing contexts of the WTRUs 102a, 102b, 102c, and the like.

[0049] The SGW 164 may be connected to the PGW 166, which may provide the WTRUs

102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices.

[0050] The CN 106 may facilitate communications 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 communications between the WTRUs 102a, 102b, 102c and traditional land-line communications devices. For example, the CN 106 may include, or may communicate with, an IP gateway (e.g., an IP multimedia subsystem (IMS) server) that serves as an interface between the CN 106 and the PSTN 108. In addition, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to the other networks 112, which may include other wired and/or wireless networks that are owned and/or operated by other service providers.

[0051] Although the WTRU is described in FIGs. 1A-1 D as a wireless terminal, it is contemplated that in certain representative embodiments that such a terminal may use (e.g., temporarily or permanently) wired communication interfaces with the communication network.

[0052] In representative embodiments, the other networks 112 may be a WLAN.

[0053] 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 an access or an interface to a Distribution System (DS) or another type of wired/wireless network that carries traffic in to and/or out of the BSS. Traffic to STAs that originates from outside the BSS may arrive through the AP and may be delivered to the STAs. Traffic originating from STAs to destinations outside the BSS may be sent to the AP to be delivered to respective destinations. Traffic between STAs within the BSS may be sent through the AP, for example, where the source STA may send traffic to the AP and the AP may deliver the traffic to the destination STA. The traffic between STAs within a BSS may be considered and/or referred to as peer-to-peer traffic. The peer- to-peer traffic may be sent between (e.g., directly between) the source and destination STAs with a direct link setup (DLS). In certain representative embodiments, the DLS may use an 802.11e DLS or an 802.11z tunneled DLS (TDLS). A WLAN using an Independent BSS (IBSS) mode may not have an AP, and the STAs (e.g., all of the STAs) within or using the IBSS may communicate directly with each other. The IBSS mode of communication may also be referred to as an "ad-hoc" mode of communication.

[0054] When using the 802.11 ac infrastructure mode of operation or a similar mode of operations, the AP may transmit a beacon on a fixed channel, such as a primary channel. The primary channel may be a fixed width (e.g., 20 MHz wide bandwidth) or a dynamically set width set via signaling. The primary channel may be the operating channel of the BSS and may be used by the STAs to establish a connection with the AP. In certain representative embodiments, Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) may be implemented, for example in 802.11 systems. For CSMA/CA, the STAs (e.g., every STA), including the AP, may sense the primary channel. If the primary channel is sensed/detected and/or determined to be busy by a particular ST A, the particular STA may back off. One STA (e.g., only one station) may transmit at any given time in a given BSS.

[0055] High Throughput (HT) STAs may use a 40 MHz wide channel for communication, for example, via a combination of the primary 20 MHz channel with an adjacent or nonadjacent 20 MHz channel to form a 40 MHz wide channel.

[0056] Very High Throughput (VHT) STAs may support 20 MHz, 40 MHz, 80 MHz, and/or

160 MHz wide channels. The 40 MHz, and/or 80 MHz, channels may be formed by combining contiguous 20 MHz channels. A 160 MHz channel may be formed by combining eight contiguous 20 MHz channels, or by combining two non-contiguous 80 MHz channels, which may be referred to as an 80+80 configuration. For the 80+80 configuration, the data, after channel encoding, may be passed through a segment parser that may divide the data into two streams. Inverse Fast Fourier Transform (IFFT) processing or time domain processing, may be done on each stream separately. The streams may be mapped on to the two 80 MHz channels, and the data may be transmitted by a transmitting STA. At the receiver of the receiving STA, the above described operation for the 80+80 configuration may be reversed, and the combined data may be sent to the Medium Access Control (MAC).

[0057] Sub 1 gigahertz (GHz) modes of operation are supported by 802.11 af and

802.11 ah. The channel operating bandwidths, and carriers, are reduced in 802.11af and 802.11 ah relative to those used in 802.11 η, and 802.11 ac. 802.11 af supports 5 MHz, 10 MHz and 20 MHz bandwidths in the TV White Space (TVWS) spectrum, and 802.11 ah supports 1 MHz, 2 MHz, 4 MHz, 8 MHz, and 16 MHz bandwidths using non-TVWS spectrum. According to a representative embodiment, 802.11 ah may support Meter Type Control/Machine-Type Communication (MTC), such as MTC devices in a macro coverage area. MTC devices may have certain capabilities, for example, limited capabilities including support for (e.g., only support for) certain and/or limited bandwidths. The MTC devices may include a battery with a battery life above a threshold (e.g., to maintain a very long battery life).

[0058] WLAN systems, which may support multiple channels, and channel bandwidths, such as 802.11 η, 802.11ac, 802.11 af, and 802.11 ah, include a channel which may be designated as the primary channel. The primary channel may have a bandwidth equal to the largest common operating bandwidth supported by all STAs in the BSS. The bandwidth of the primary channel may be set and/or limited by a STA, from among all STAs in operating in a BSS, which supports the smallest bandwidth operating mode. In the example of 802.11 ah, the primary channel may be 1 MHz wide for STAs (e.g., MTC type devices) that support (e.g., only support) a 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. If the primary channel is busy, due to a STA, such as a 1 MHz operating mode STA, transmitting to the AP, whole frequency bands may be considered busy even though a majority of frequency bands remain idle and may be available.

[0059] In the United States, the available frequency bands, which may be used by

802.11ah, are from 902 MHz to 928 MHz. In Korea, the available frequency bands are from 917.5 MHz to 923.5 MHz. In Japan, the available frequency bands are from 916.5 MHz to 927.5 MHz. The total bandwidth available for 802.11 ah is 6 MHz to 26 MHz depending on the country code.

[0060] FIG. 1 D is a system diagram illustrating the RAN 104 and the CN 106 according to an embodiment. As noted above, the RAN 104 may employ an NR radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 104 may also be in communication with the CN 106.

[0061] The RAN 104 may include gNBs 180a, 180b, 180c, though it will be appreciated that the RAN 104 may include any number of gNBs while remaining consistent with an embodiment. The gNBs 180a, 180b, 180c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the gNBs 180a, 180b, 180c may implement MIMO technology. Also, in an example, gNBs 180a, 180b, 180c may utilize beamforming to transmit signals to and/or receive signals from the WTRUs 102a, 102b, 102c. Thus, the gNB 180a, for example, may use multiple antennas to transmit wireless signals to, and/or receive wireless signals from, the WTRU 102a. In an embodiment, the gNBs 180a, 180b, 180c may implement carrier aggregation technology. For example, the gNB 180a may transmit multiple component carriers (not shown) to the WTRU 102a. A subset of these component carriers may be on unlicensed spectrum while the remaining component carriers may be on licensed spectrum. In an embodiment, the gNBs 180a, 180b, 180c may implement Coordinated Multi-Point (CoMP) technology. For example, WTRU 102a may receive coordinated communications from gNB 180a and gNB 180b (and/or gNB 180c).

[0062] The WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using communications associated with a scalable numerology. For example, the OFDM symbol spacing and/or OFDM subcarrier spacing (SCS) may vary for different communications, different cells, and/or different portions of the wireless communication spectrum. The WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using subframe or transmission time intervals (TTIs) of various or scalable lengths (e.g., containing varying number of OFDM symbols and/or lasting varying lengths of absolute time). [0063] 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 the standalone configuration, WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c without also accessing other RANs (e.g., such as eNode-Bs 160a, 160b, 160c). In the standalone configuration, WTRUs 102a, 102b, 102c may utilize one or more of gNBs 180a, 180b, 180c as a mobility anchor point. In the standalone configuration, WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using signals in an unlicensed band. In a non-standalone configuration WTRUs 102a, 102b, 102c may communicate with/connect to gNBs 180a, 180b, 180c while also communicating with/connecting to another RAN such as eNode-Bs 160a, 160b, 160c. For example, WTRUs 102a, 102b, 102c may implement DC principles to communicate with one or more gNBs 180a, 180b, 180c and one or more eNode-Bs 160a, 160b, 160c substantially simultaneously. In the non-standalone configuration, eNode-Bs 160a, 160b, 160c may serve as a mobility anchor for WTRUs 102a, 102b, 102c and gNBs 180a, 180b, 180c may provide additional coverage and/or throughput for servicing WTRUs 102a, 102b, 102c.

[0064] 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 of network slicing, dual connectivity, interworking between NR and E-UTRA, routing of user plane data towards User Plane Function (UPF) 184a, 184b, routing of control plane information towards Access and Mobility Management Function (AMF) 182a, 182b and the like. As shown in FIG. 1 D, the gNBs 180a, 180b, 180c may communicate with one another over an Xn interface.

[0065] The CN 106 shown in FIG. 1 D may include at least one AMF 182a, 182b, at least one UPF 184a, 184b, at least one Session Management Function (SMF) 183a, 183b, and possibly a Data Network (DN) 185a, 185b. While each of the foregoing elements are depicted as part of the CN 106, it will be appreciated that any of these elements may be owned and/or operated by an entity other than the CN operator.

[0066] The AMF 182a, 182b may be connected to one or more of the gNBs 180a, 180b,

180c in the RAN 104 via an N2 interface and may serve as a control node. For example, the AMF 182a, 182b may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, support for network slicing (e.g., handling of different protocol data unit (PDU) sessions with different requirements), selecting a particular SMF 183a, 183b, management of the registration area, termination of non-access stratum (NAS) signaling, mobility management, and the like. Network slicing may be used by the AMF 182a, 182b in order to customize CN support for WTRUs 102a, 102b, 102c based on the types of services being utilized 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 communication (URLLC) access, services relying on enhanced massive mobile broadband (eMBB) access, services for MTC access, and/or the like. The AMF 182a, 182b may provide a control plane function for switching between the RAN 104 and other RANs (not shown) that employ other radio technologies, such as LTE, LTE-A, LTE-A Pro, and/or non-third generation partnership project (3GPP) access technologies such as WiFi.

[0067] The SMF 183a, 183b may be connected to an AMF 182a, 182b in the CN 106 via an N11 interface. The SMF 183a, 183b may also be connected to a UPF 184a, 184b in the CN 106 via an N4 interface. The SMF 183a, 183b may select and control the UPF 184a, 184b and configure the routing of traffic through the UPF 184a, 184b. The SMF 183a, 183b may perform other functions, such as managing and allocating WTRU IP address, managing PDU sessions, controlling policy enforcement and QoS, providing downlink data notifications, and the like. A PDU session type may be IP-based, non-IP based, Ethernet-based, and the like.

[0068] The UPF 184a, 184b may be connected to one or more of the gNBs 180a, 180b,

180c in the RAN 104 via an N3 interface, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices. The UPF 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 DL packets, providing mobility anchoring, and the like.

[0069] The CN 106 may facilitate communications with other networks. For example, the

CN 106 may include, or may communicate with, an IP gateway (e.g., an IP multimedia subsystem (IMS) server) that serves as an interface between the CN 106 and the PSTN 108. In addition, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to the other networks 112, which may include other wired and/or wireless networks that are owned and/or operated by other service providers. In one embodiment, the WTRUs 102a, 102b, 102c may be connected to a local DN 185a, 185b through the UPF 184a, 184b via the N3 interface to the UPF 184a, 184b and an N6 interface between the UPF 184a, 184b and the DN 185a, 185b.

[0070] In view of FIGs. 1A-1 D, and the corresponding description of FIGs. 1A-1 D, one or more, or all, of the functions described herein with regard to one or more of: WTRU 102a-d, Base Station 114a-b, eNode-B 160a-c, MME 162, SGW 164, PGW 166, gNB 180a-c, AMF 182a-b, UPF 184a-b, SMF 183a-b, DN 185a-b, and/or any other device(s) described herein, may be performed by one or more emulation 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 functions.

[0071] The emulation devices may be designed to implement one or more tests of other devices in a lab environment and/or in an operator network environment. For example, the one or more emulation devices may perform the one or more, or all, functions while being fully or partially implemented and/or deployed as part of a wired and/or wireless communication network in order to test other devices within the communication network. The one or more emulation devices may perform the one or more, or all, functions while being temporarily implemented/deployed as part of a wired and/or wireless communication network. The emulation device may be directly coupled to another device for purposes of testing and/or may perform testing using over-the-air wireless communications.

[0072] The one or more emulation devices may perform the one or more, including all, functions while not being implemented/deployed as part of a wired and/or wireless communication network. For example, the emulation devices may be utilized in a testing scenario in a testing laboratory and/or a non-deployed (e.g., testing) wired and/or wireless communication network in order to implement testing of one or more components. The one or more emulation devices may be test equipment. Direct RF coupling and/or wireless communications via RF circuitry (e.g., which may include one or more antennas) may be used by the emulation devices to transmit and/or receive data.

[0073] In wireless communications, a reference symbol may be utilized to denote a symbol such as a complex number that is fixed or known. A reference symbol may be utilized as a pilot. A reference signal may be utilized to denote a time domain signal that is generated from processing the reference symbols. In OFDM, reference symbols may be complex numbers inputted to an inverse discrete Fourier transform (IDFT) block while the reference signal is the output of the IDFT block. A resource element (RE) may be one or more OFDM symbols on one or more subcarriers, and a resource element group (REG) may comprise a group of REs. A group of REs may be utilized as building blocks of a control channel element (CCE) that assigns REs to a user. REGs that are adjacent in time or frequency, proximate in time or frequency, grouped together, clustered, or the like may be designated as REG bundles, that may be associated with the same pre-code so that channel estimation may be efficiently performed together. The examples given herein comprise different examples of REG sizes, REG bundle sizes, group sizes, or the like. However, any size may be configured for embodiments given herein.

[0074] In LTE, a common physical downlink control channel (PDCCH), physical control format indicator channel (PCFICH), or other control channels may be configured to transmit common signaling for scheduling downlink information, detection of WTRU-specific PDCCH, or the like. For NR or 5G, an NR-REG, NR-CCE, or NR-PDCCH may be similar to a REG, CCE, or PDCCH, respectively. In NR or 5G, a group-common PDCCH may be configured as a physical channel that carries downlink control information (DCI) intended for a group or cluster of WTRUs. Utilizing 5G NR in millimeter-wave (mmW) frequencies, beam-based transmission, groupings of WTRUs based on transmit and receive beams, or the like may need diverse control operations. A group-common PDCCH may be used by a set or a sub-set of the WTRUs within a cell or beam for scheduling.

[0075] A group-common PDCCH may be utilized with a WTRU-specific PDCCH or common PDCCH. A group-common PDCCH may also operate independently. When a group- common PDCCH is assigned to a group or subset of WTRUs, multiple group-common PDCCH channels may be configured. In this configuration, a WTRU may be assigned to one or more group- common PDCCH channels. Assignment may be static, semi-static, dynamic, or the like. In a configuration, group-common PDCCH parameters, group-common PDCCH search space parameters, or the like may be assigned during WTRU initialization, setup, registration, or the like. A WTRU may also be added or removed from a group by a WTRU specific signal communicated using the PDCCH, during beam management or reconfiguration, during beam failure, during beam recovery, or the like.

[0076] A group-common PDCCH may include a slot configuration, group-Identification (ID), a starting position of physical downlink shared channel (PDSCH) in one or more slots, an end position of a DL control resource set (CORESET) in one or more slots, an UL scheduling request (SR) resource configuration, a DL pre-emption indication for the previous slot, an UL pre-emption indication for the previous slot, a DL acknowledgment (ACK) related to UL data communications or transmissions, information about limiting a WTRU-specific search space, information about blind decoding over a subset of a WTRU-specific search space, an indication of transmission length on a data channel, a resource block group (RBG) size, presence or patterns of phase tracking RS (PT- RS) indication, DL beam indication, dynamic configuration of interference measurement resources (IMRs), or the like.

[0077] Slot configurations or formats may include DL, UL, sidelink, half-duplex, full-duplex, reserved, unknown, empty, blank, or the like. A slot configuration may be related to the current slot or aggregated slots, aggregated mini-slots, the next slot, or the like. For semi-statically configured slot formats, dynamic slot configuration may overwrite an existing semi-static configuration. A slot format indicator (SFI) may indicate the format for one or multiple slots. When a SFI indicates the format for multiple slots, information about the number of slots, explicitly, or implicitly may also be included. An SFI may be related to a current slot, the next slot, the next multiple slots, or the like. A variable number of bits may be utilized to indicate a slot format. A format indicated as empty may signal no communication or transmission from a gNB and may be utilized for interference estimation and cancelation by a WTRU or transceiver. A format indicated as unknown may signal possible communication or transmission from the gNB. A WTRU may be configured to process an unknown format, skip processing on the received signal on an unknown slot, or the like.

[0078] A pre-emption indication for UL, that may be communicated or transmitted as one or more bits by a group-common PDCCH, may indicate communication or transmission by an URLLC WTRU, loss of communication or transmission by eMBB WTRUs in the UL on one or multiple previous slots or one or multiple code block groups (CBGs). Pre-emption indication for DL, that may be communicated or transmitted as one or more bits by group-common PDCCH, may indicate communication or transmission intended for a URLLC WTRU and pre-emption of the communication or transmission is intended for the eMBB WTRUs in the DL, on one or multiple previous slots or one or multiple CBG. Pre-emption indication may also indicate how a transceiver, WTRU, or the like utilize RSs during decoding, such as for an eMBB or any other wireless device.

[0079] For paging and system information, paging messages, such as for radio resource control (RRC) idle mode, may be scheduled by a group-common DCI (GC-DCI) carried by a group- common PDCCH, by WTRU-specific DCI carried by WTRU-specific NR-PDCCH, communicated or transmitted in the associated NR-PDSCH, or the like. In addition, for an indication of limiting WTRU- specific search spaces, a GC-DCI may contain information about limiting blind detection of a WTRU- specific PDCCH to a part or portion of a WTRU-specific search space. For example, a WTRU- specific search space may span multiple OFDM symbols and a GC-DCI may indicate limiting blind detection to PDCCH candidates of the search space that are on a specific OFDM symbol or symbols.

[0080] For an indication of a starting position of a PDSCH in the slot, a group-common

PDCCH may include information about the start of the data channel in a slot for a group or cluster of WTRUs. The start of the PDSCH may be different or align with the end of a control region. For an indication of transmission length on a data channel, the duration of a data transmission in a data channel may be semi-statically configured or dynamically indicated in the PDCCH scheduling the data communication or transmission.

[0081] A unified GC-DCI or a unified group-common PDCCH may have a structure similar to a NR-PDCCH. Similar features of a structure may include REGs, REG bundles, CCEs, CCE aggregation, mapping of CCEs to a group-common PDCCH, channel coding, cyclic redundancy check (CRC), or the like. In a unified configuration, the search space for group-common PDCCH may be similar as the common search space for PDCCH. A unified group-common PDCCH may also partially re-use a NR-PDCCH structure. Partial or complete re-use of a PDCCH structure may utilize REGs; REGs and REG bundles; REGs, REG bundles, and CCEs; or REGs, REG bundles, and CCEs and similar forward error correction (FEC) and CRC structure as a PDCCH.

[0082] FIG. 2 is a diagram of an exemplary REG structure 200 for a group-common

PDCCH. For REG configurations, a REG structure, such as one with a RE mapping and DMRS similar to NR-PDCCH or with a unique DMRS structure, may be utilized by group-common PDCCH. In REG structure 200, REGs 0-23 for symbols 202 and 204 may be not grouped as REG bundles for data 206 as REG 0, REG 8, and REG 16 are distributed.

[0083] FIG. 3 is a diagram of an exemplary structure utilizing REGs and REG bundles in

300 for a group-common PDCCH. When utilizing REGs and REG bundles, both REG structure and REG bundling similar to NR-PDCCH configurations with a different CCE structure may be used. REGs 0-23 for symbols 302 and 304 are configured with REGs, REG bundles, and data 306. In 300, REG bundles may comprise (REG 0, REG 1), (REG 4, REG 5), (REG 8, REG 9), (REG 12, REG 13), and (REG 16, REG 17). However, any combination, sequence, group, or the like of REGs may comprise a bundle.

[0084] FIG. 4 is a diagram of an example 400 of utilizing REG, REG bundles, and CCEs and a FEC and a CRC in relation to a PDCCH. In 400, REG bundles in 402 and 404 may comprise (REG 0, REG 1), (REG 8, REG 9), and (REG 16, REG 17) with data 406. When configuring REGs, REG bundles, and CCEs, a resource mapping may be configured similar to NR-PDCCH in time or frequency with CCEs having six REGs. In another configuration, in 408 REG bundles may include (REG 0, REG 1), (REG 4, REG 5), and (REG 8, REG 9) with a CORESET 2 in 410 and data 412. In 400, when using REGs, REG bundles, and CCEs and similar FEC and CRC as a PDCCH, transmission schemes, FEC, error detection, CRC, or the like may be configured similar to NR- PDCCH.

[0085] In certain configurations, two types of GC-DCI and two types of group-common

PDCCHs may be configured. A light, small, or short GC-DCI may be communicated or transmitted on a light, small, or short group-common PDCCH. An extended, large, or long GC-DCI may be communicated or transmitted on an extended, large, or long group-common PDCCH. Table 1 is an example of contents of light and extended GC-DCIs. Light GC-DCI Extended GC-DCI

• SFI • Group-ID

• DL Pre-emption Indication of • Starting Position of PDSCH in a Slot

Previous Slot • End Position of DL CORESET in a Slot

• UL SR Resource Configuration

• DL ACK related to UL Data

Communications

• Information Restricting UE-specific Search

Space and Blind Decoding over Subset of

UE-specific Search Space

• RBG Size

fable 1

A light DCI of a group-common PDCCH may include an SFI, pre-emption indication, or the like with a size of one or more bits.

[0086] For the structure and transmission of a light group-common PDCCH, the group- common PDCCH may be communicated or transmitted in the first OFDM symbol of a slot. Configuring the PDCCH in the first OFDM symbol of a slot may be utilized by the WTRU to identify the slot configuration as early as possible to reduce the number of blind decoding operations when a group-common PDCCH carries the information regarding the DL CORESET configuration, DL CORESET duration, or the like.

[0087] FIG. 5 is a diagram of an example 500 of mapping a group-common PDCCH to the first OFDM symbol of a CORESET over slot 1 and slot 2. A group-common PDCCH may be mapped to six REGs of symbol 502 that may comprise three bundles of two REGs: (REG 0, REG 1 ), (REG 6, REG 7), and (REG 12, REG 13.) REG bundles may be distributed in the frequency domain across a DL CORESET bandwidth. The mapping of group-common PDCCH to resource elements (k, I) in the DL CORESET may be in increasing order of the index k, which may mean frequency-first mapping while / =1 In 500, symbol 506 may be configured as the 1 ^st OFDM symbol of a CORESET in slot 1 and symbols 504 and 508 may be configured as the 2 ^nd OFDM symbol of a CORESET in slot 2.

[0088] A group-common PDCCH may apply different channel coding, error detection, error correction, or the like schemes on a payload for communication or transmission depending on content. A payload may include data, control, data and control, or any other information for communication or transmission. In certain configurations, a group-common PDCCH may be communicated without error detection or correction. As an example, if a group-common PDCCH is carrying a hybrid automatic repeat request (HARQ) ACK response corresponding to a UL data communication or transmission, such as on an uplink shared channel (UL-SCH) or physical uplink shared channel (PUSCH), then the one or more bits of an ACK or negative ACK (NACK) may be encoded using repetition coding, simplex coding, or the like without appending a CRC to the payload. When a group-common PDCCH is carrying a dynamic indication to signal to a group or cluster of WTRU(s) of assigned downlink resources in the previous slot partially being pre-empted by another downlink communication or transmission, then an indication may be encoded using repetition coding or simplex coding without appending a CRC to the payload.

[0089] In the absence of error detection or correction, a WTRU may need to identify when a group-common PDCCH is carrying information intended for that WTRU. For example, the WTRU may receive an indicator in the DCI carried by the group-common PDCCH regarding the group-ID for the WTRU. FIG. 6 is an exemplary mapping 600 of a group-ID to the indicator in the DCI. Bits 602 may be mapped to various group-IDs 604. A group-ID may identify a beam from which a group of UEs are scheduled to receive information. In 600, a scheduler may divide WTRUs among eight groups where each group or cluster of WTRUs may be served by a different beam. In 600 or other configurations, a group-ID may be a function of a beam-ID over which the group-common PDCCH is communicated or transmitted.

[0090] FIG. 7 is an exemplary mapping 700 of a group-ID to an implicit indicator in the

DCI. In 700, a WTRU may be configured to implicitly deduce the information related to a group-ID using a circularly shifted scrambling sequence where shifts 702 are mapped to group-IDs 704. A group-common PDCCH payload may be scrambled after channel coding with a sequence that may be a function of cell-ID, group-ID, beam-ID, or the like. A WTRU may perform blind detection of the group-ID with the hypothesis of no cyclic shift and one or more cyclic shifts of the scrambling sequence.

[0091] As an example, a sequence b(0), b(1),...b(M-1) may be scrambled with a sequence c(0), c(1), ...c(M-1) when the WTRU belongs to Group 1. In this configuration, the scrambling sequence is not cyclically shifted. For Group 2, the sequence of b(0), b(1),...b(M-1) may be scrambled with a sequence c(M-1), c(0), c(1), ...c(M-2), which implies that the scrambling sequence is cyclically shifted by one element. For Group 3, the sequence of b(0), b(1),...b(M-1) may be scrambled with a sequence c(M-2), c(M-1), c(0), c(1), ...c(M-3), which implies that the scrambling sequence is cyclically shifted by two elements. This technique may similarly be configured for Groups 4-6.

[0092] FIG. 8 is an example 800 of a group-ID indication using a block-wise circular shifted scrambling sequence. In 800, a group-ID may be implicitly deducted by the WTRU where a scrambling sequence is cyclically shifted block-wise instead of element-by-element. Example 800 comprises REGs 0-15 (804) and cyclic shifts 0-5 (802). The size of a block may be similar in length as that of a REG, such as 12, or a REG bundle, such as 24 for REG bundle of two or 36 for REG bundle of three. In example 800, Group 2 may comprise sequence of b(0), b(1), ...b(M-1) scrambled with a sequence of c(M-N), c(M-N+1), ..., c(M-1), c(0), c(1),...c(M-N-1) when the WTRU belongs to Group 1 where N represents the block length used for each circular shift.

[0093] In certain configurations, a group-common PDCCH may be communicated or transmitted with error detection. When the group-common PDCCH is carrying the slot format configuration together with other control information, then a CRC may be appended to the payload before channel coding. Channel coding may utilize Reed-Muller codes, polar codes, or the like and may depend upon payload or data portion sizes. If a group-common PDCCH is carrying a HARQ ACK response corresponding to the UL data communication or transmission of a group or cluster of WTRU(s), then the HARQ ACK/NACK from each WTRU in a group may be jointly encoded using Reed-Muller or polar code after appending a CRC operation. In another configuration, if the group- common PDCCH is carrying the paging information or system information, then a CRC may be appended to the payload before channel coding.

[0094] As explained herein, A WTRU may identify when a group-common PDCCH is carrying information intended for that WTRU by detection of a common RNTI masking a CRC. The common RNTI may be assigned to a group or cluster of WTRUs in the system by the scheduler or other component in the network. A WTRU may be configured with a common RNTI and WTRU- specific RNTI.

[0095] In a certain configuration, when error detection is utilized for content of group- common PDCCH, a trade-off between error correction and error detection may exist based on a minimum Hamming distance. As an example, an error correcting code with minimum Hamming distance of d may be used to correct /ci bits of error and detect fe bits of error as long as 2/ + k ₂ < d. When the block error correcting code used for encoding of a group-common PDCCH has a large minimum distance, it may be used for error correction and error detection. In a configuration for encoding the payload of the group-common PDCCH, a Reed-Muller code of [32, 6, 16] with a length of 32 bits and that encodes six bits with the minimum Hamming distance of 16 may be utilized. Since the minimum Hamming distance of the code is 16, up to three bits of error may be corrected and up to nine bits of error may be detected since (2x 3 + 9) < 16. This configuration is similar to utilizing a CRC length of nine bits.

[0096] Error detection using thresholds on soft detection metrics may also be utilized for content of a group-common PDCCH. A WTRU may be configured to utilize a threshold for an absolute value of soft detection metrics to decode bits, such as log likelihood ratio (LLR), for error detection without CRC. A WTRU may conclude that the decoded bits are valid decoded bits if the corresponding LLRs have the absolute value larger than a certain threshold. A WTRU may consider decoded bits as invalid decoded bits if corresponding LLRs have the absolute value smaller than a certain threshold. If one or a certain number of bits of a codeword are invalidated by the WTRU then the decoded codeword may be designated as an error.

[0097] A binary error correcting code may also be configured for error detection for content of a group-common PDCCH. When a subset of a binary error correcting code is configured, the difference between the subset and the whole or rest of the code may be used for error detection. If the decoded codeword does not belong to the specified subset, then it may be an error. For example, if a Reed-Muller code of [32, 16, 8] is used and instead of encoding 16 bits of data, the Reed-Muller code is used to encode 11 bits of information, an error detection probability of 2-5 may be expected that is similar to a CRC of length five.

[0098] In certain configurations, an extended group-common PDCCH may be used to transmit the extended GC-DCI, which may include the remaining GC-DCI left out of the light GC- DCI. The content of extended GC-DCI may include group-ID, information related to a beam for a group or cluster of WTRUs scheduled to receive information, starting position of a PDSCH in the slot, end position of DL CORESET in the slot, UL SR resource configuration, DL pre-emption indication for the previous slot, DL ACK related to the UL data communications or transmissions, or information related to restricting a WTRU-specific search space and performing blind decoding over a subset of the WTRU-specific search space. An extended group-common PDCCH may be structured to partially or completely re-use the structure of NR-PDCCH similar to a unified group- common PDCCH.

[0099] For transmitting group-common PDCCH carrying SFI, different communication or transmission modes may be configured. Communication or transmission modes may be a function of payload length, CRC, channel encoding, or the like. As an example, a CRC-based communication or transmission mode may use polar codes as forward error correction and a CRC- less communication or transmission mode may use Reed-Muller codes. Communication or transmission mode of a group-common PDCCH carrying SFI may be fixed, pre-configured, or the like.

[00100] Transmission mode may also be configurable by information on a physical broadcast channel (PBCH), higher layer signaling, RRC signaling, or the like. Configuration information of the communication or transmission mode for the group-common PDCCH carrying SFI may include parameters for a CORESET, allocated resources, CCEs, REGs, a REG bundle size, a REG bundle to CCE mapping, an encoding scheme, polar codes, Reed-Muller codes, an error detection scheme, CRC information, a monitoring rate of the group-common PDCCH carrying SFI, SFI payload size, or the like. A WTRU may implicitly deduce a configuration parameter of the group- common PDCCH carrying SFI from other parameters. [00101] The monitoring rate for a GC-PDCCH may be variable. The monitoring rate for multiple or aggregated slots may vary as once per multiple slots while for the case of single slot may be per slot. When the monitoring rate is once per slot, the WTRU may determine that the payload size is n bits and when the monitoring rate is once every m aggregated slots, the WTRU may determine that the payload size is up to m times n bits.

[00102] A payload size of SFI may be dependent on a monitoring rate. In the event that the SFI carries the information corresponding to multiple slots, aggregated slots, or the like, the payload may be larger than when the SFI carries information for a single slot. In certain configurations, a channel encoding scheme may be determined based on the SFI payload size. When the SFI payload size is smaller than a threshold, or when the monitoring rate is once every slot, a WTRU may be configured to determine that the channel coding scheme is Reed-Muller code. When the SFI payload size is larger than a certain threshold or when the monitoring rate is once every multiple slots, the WTRU may determine that the channel coding scheme is polar code.

[00103] Configurations utilizing a CRC may be determined based on a SFI payload size. When the SFI payload size is smaller than a threshold or when the monitoring rate is once every slot, the WTRU may determine that no CRC is attached to the SFI payload. When the SFI payload size is larger than certain threshold or when the monitoring rate is once every multiple slots, the WTRU may determine that a CRC is attached to the payload. The CRC length may be fixed, predetermined, or the WTRU may implicitly determine the CRC length based on the SFI payload.

[00104] Allocated resources may be determined based on the channel encoding scheme. If polar coding with CRC is configured, the WTRU may determine that the aggregation level, that determines the number of allocated CCEs, is larger than when Reed-Muller channel coding without CRC is configured. The WTRU may also implicitly derive the location of the allocated resources, such as the first CCE index, based on a channel coding and error detection scheme. Allocated resources may also be determined based on the SFI payload size. When the SFI payload size is smaller than a threshold, the WTRU may determine a smaller aggregation level is configured. When the SFI payload size is larger than a certain threshold, the WTRU may determine a larger aggregation level is configured.

[00105] FIG. 9 is a diagram of an example 900 of a dynamic group-common PDCCH with three types of information. Although three types are shown in the example, any number of PDCCH types may be configured or utilized. PDCCH type 1 may include DCIs 1-4. PDCCH type 2 may include DCI 2 and DCIs 5-7. PDCCH type 3 may include DCIs 3-7. The contents of the group- common PDCCH may be dynamically changed based on communicated information. A PDCCH type may also be assigned independent search space parameters and WTRUs assigned to a group may be signaled by the search space parameters. In addition, a PDCCH type may be communicated at different periodicities with the periodicity of a specific GC type set statically, semi- statically, dynamically, or the like.

[00106] FIG. 10 is a diagram of an example 1000 of a dynamic group-common PDCCH with a DCI index. In 1000, the group-common PDCCH may send DCI index 1 , 3, and 4 that indicates the contents of the PDCCH DCI 1, DCI 3, and DCI 4, respectively. The WTRU may read the index and based on this identify communicated information. In addition, a group-common PDCCH may be comprised of a finite set, each with an index indicating the DCI information contents that are communicated. The WTRU may read the index and identify the contents of the communication or transmission. An index may be communicated in a light group-common PDCCH with additional resource information indicating location of the remaining group-common PDCCH.

[00107] A GC-DCI may also be communicated on a PDCCH. Common control information to a group or cluster of WTRUs may be configured or structured similar to a WTRU-specific PDCCH but with masking the associated CRC with a group-common RNTI, a common RNTI, system- information RNTI (SI-RNTI), or the like. With this configuration, different types of common DCI or GC-DCI with different corresponding search spaces or different corresponding types of RNTI may be utilized.

[00108] The content of a GC-DCI may include a pre-emption indication for downlink that may indicate to a group or cluster of WTRUs that a set of resources are punctured in the previous slot or slots. Pre-emption may also signify that slots are utilized for URLLC devices. The granularity of resources in frequency may be in the RBG size, a multiple of a RBG size, blocks of k RBGs for an integer number k, a fraction of a system bandwidth, a fraction of the bandwidth part, or the like. The granularity of pre-emption indication in frequency may be semi-statically configured by higher layer signaling, RRC signaling, or the like. The granularity of the pre-emption indication in time may be every symbol, a multiple of a symbol, a slot, a fraction of a slot, or the like.

[00109] The size of a DCI may be lowered with a high granularity of pre-emption indication in time or frequency. A punctured region may be a contiguous region in time and frequency. When contiguous, the beginning or end of the punctured region may need to be signaled. If the granularity of pre-emption indication results in Nf possible blocks in frequency and Nt blocks in time, then at least log + log bits may be needed for transmission where log(.) is logarithm in base

2, and is the number of combinations of 2 out of n (or "n choose 2"). As an example, if the granularity of indication in frequency is 1/20 of the bandwidth, and if the beginning and the end of the pre-emption can be every symbol among the 14 symbols of the last slot, the number of bits may

[00110] The frequency and time indication of a DCI may be mapped separately. For example, the 190 possibilities of the beginning and end of pre-emption in frequency may be sent by eight bits and the 91 possibilities of the beginning and end of pre-emption in time may be sent by seven bits. To map the information to bits, available possibilities may be indexed and the index may be sent in base 2.

[00111] FIG. 11 is a flowchart of an example WTRU procedure 1100 for group-common

PDCCH reception. A CORESET configuration and GC-RNTI may be obtained through the PBCH, RRC signaling, higher layer signaling, or the like (1102). A common search space may be monitored for one or more common DCIs every T2 time slots (1104). Blind detection (1106) and decoding of the common DCI (1108) may be performed for the group-common PDCCH. If configured, an assigned location or search space may be monitored for a group-common PDCCH once every T1 slots (1110) or at a variable rate and SFI may be decoded (1112).

[00112] When utilizing a unified group-common PDCCH, a common search space may be used for monitoring and blind detection of the group-common PDCCH. A common search space may overlap with WTRU-specific search spaces. In this configuration, or when the light and extended group-common PDCCH have similar structures, a WTRU may perform multiple blind decodings on each PDCCH candidate corresponding to multiple DCI formats.

[00113] Each DCI format of a different payload size may correspond to a light or an extended group-common PDCCH. A DCI format corresponding to the light group-common PDCCH, such as a short-GC-DCI, may carry a much smaller message size while a DCI format corresponding to the extended group-common PDCCH, such as long-GC-DCI, may carry a much larger message size. In this configuration, a WTRU may be configured to perform at least two or more blind decodings for each PDCCH candidate to detect control messages for the WTRU and communicated or transmitted on the group-common PDCCH.

[00114] A single message size, such as a GC-DCI, may also be defined for light and extended group-common PDCCH. In this configuration, a WTRU may perform one blind decoding attempt for each PDCCH candidate to distinguish different group-common control messages. A WTRU may de-scramble a CRC attached to a message and differentiate light and extended group- common PDCCHs based on different identifiers, such as a RNTI, masking the CRC for each group- common message. A WTRU may determine that the identifier implicitly indicating a group-common message using the CRC for SFI is SFI-RNTI, the identifier for preemptive indication is PI-RNTI, the identifier for remaining system information (RMSI)-RNTI, or the like.

[00115] In another configuration, the WTRU may differentiate a light and extended group- common PDCCH by detecting one or more bit(s) indication field transmitted in the GC-DCI. When configured, the indication field may be utilized by a WTRU to differentiate GC-DCI formats among similar sized messages for both light and extended group-common PDCCH.

[00116] A short message corresponding to the light group-common PDCCH may be padded with zeros, ones, or the like to ensure light and extended group-common PDCCHs have similar payload sizes. Without padding, the WTRU may need to perform multiple blind decodings corresponding to multiple GC-DCI sizes. Multiple blind decodings may increase computational complexity, overhead, power usage, or the like.

[00117] Light and extended group-common PDCCHs may be configured with different search spaces and structures. An extended group-common PDCCH may be configured with a structure similar to a NR-PDCCH and use a common search space. A common search space may overlap with WTRU-specific search spaces. The light group-common PDCCH may be configured with a separate search space without overlap with WTRU-specific search spaces.

[00118] A monitoring rate may vary for light and extended group-common PDCCHs. The rate may be once in a slot, once in several slots, or the like. The monitoring rate may be configured semi-statically by RRC signaling or dynamically by the group-common PDCCH to change the monitoring rate over time.

[00119] CORESET information carried by a PBCH may be utilized by a WTRU to configure a group-common PDCCH for a given numerology and may be utilized to receive both group- common and WTRU-specific PDCCHs. When multiple CORESETs are configured by a PBCH, at least one of the CORESETs may be configured to carry the group-common PDCCH. In this configuration, a WTRU may still receive the WTRU-specific PDCCH carrying a DL assignment or an UL grant on the group-common search space.

[00120] When utilizing a PBCH, a group-common PDCCH may be communicated or transmitted on the first OFDM symbol of a slot for a CORESET. In this configuration, a WTRU may receive a SFI as early as possible in the slot and make available bits in the master information block (MIB) depending on the system bandwidth for communicating other desired information on the PBCH. In an example, for a time duration of three OFDM symbols for control channel communication or transmission, up to two bits may be utilized to indicate the starting OFDM symbol of a CORESET. For this configuration, the WTRU may determine that the CORESET configured by PBCH starts from the first OFDM symbol in the slot. In addition, a time duration of a CORESET configured by a PBCH may be configured as a pre-determined or fixed length of one OFDM symbol or independent of the carrier bandwidth. This configuration may make available an up to two bits in MIB for other control information.

[00121] When a CORESET is configured with one CCE-to-REG mapping, the WTRU may determine an interleaved REG-to-CCE mapping for a CORESET(s) configured utilizing the PBCH. In a configuration, the REGs for a given CCE may be grouped as a REG bundle and then REG bundles may be interleaved in the CORESET. REG bundle size for CORESET(s) configured by PBCH may be small to optimize or maximize frequency diversity gain for the group-common PDCCH.

[00122] In certain configurations, CORESET information carried by a PBCH may be specific to a frequency resource configuration. Information related to the numerology of RMSI may be included in a MIB to reduce monitoring for group-common PDCCH carrying slot format related information, such as a SFI, in a slot. A CORESET(s), other than those configured by a PBCH, that carries a WTRU-specific search space may be configured semi-statically by utilizing a MIB.

[00123] A search space for a common PDCCH may be related to configurations for group- common PDCCH monitoring. Monitoring a group-common PDCCH, such as one with a SFI, and the PDCCH carrying common DCI, such as a GC-DCI, may utilize a common search space or a group- common search space and utilize a fixed or predetermined location for the group-common PDCCH inside the given search space. A common search space may be monitored by WTRUs in a cell while a group-common search space may be monitored by WTRUs inside a group. A fixed or predetermined location may be the location of a PDCCH candidate with a fixed index inside that common or group-common search space.

[00124] A group-common search space may be a function of group-common RNTI (GC- RNTI), Cell ID, or other parameters. The group-common search space may include several PDCCH candidates with different aggregation levels. The location of one of the candidates of the group- common search space, for example the candidate with index 0, may be used for sending a group- common PDCCH carrying SFI at the beginning of a time slot. Monitoring a group-common PDCCH carrying SFI may vary from a GC-DCI carried by PDCCH. For example, the group-common search space may be monitored and blind decoded at every slot and the location of the candidate with a fixed index may be monitored every other slot for group-common PDCCH carrying SFI. In addition, a similar location in the search space may be used alternatively for monitoring SFI and pre-emption indication at every other slot. A group-common PDCCH carrying SFI may also be monitored at a fixed candidate or a fixed location inside the common search space that is determined or scrambled by a SI-RNTI. [00125] A SFI may be dynamic and may have an indicator or implicit indication of a slot format. For this configuration, a mapping between the content of dynamic SFI communicated or transmitted by group-common PDCCH, and the format of a corresponding slot or slots may be utilized. An indication of the dynamic slot format based on the content of dynamic SFI and a fixed or configurable table may be utilized.

[00126] Moreover, dynamic indication of a slot format for a slot or a set of slots may utilize a table, dependent on a SFI payload size, that indicates the format of the slot or the format of each slot in the associated set of slots based on the content of the dynamic SFI. Table 2 shows an example of an indication of the slot format based on the content of the dynamic SFI for the payload size of three bits. A DL-centric slot may primarily include downlink symbols, or be configured to support a slot-based PDSCH, without PUSCH. An UL-centric slot may primarily include uplink symbols, or be configured to support a slot based PUSCH, without a PDSCH. An unknown-centric or unknown slot may primarily include symbols that are unknown.

Table 2

[00127] A table may be utilized to map a dynamic SFI to the format configuration of a slot or a set of contiguous or non-contiguous slots. This configuration may be signaled through RRC signaling, higher layer signaling, or the like. This configuration may also be setup with the configuration of dynamic SFI payload size and related monitoring periodicity or rate.

[00128] Table 3 shows an example of different types of dynamic SFI mapping using a bitmap. In this example, four bits signaled in the SFI may indicate the type of dynamic SFI mapping for a slot or a set of slots.

Table 3

[00129] Monitoring periodicity or rate of a dynamic SFI may also be configured by RRC, higher layer signaling, or the like. Table 4 shows an example of dynamic SFI monitoring periodicity by three bits.

Table 4 [00130] A WTRU may implicitly determine a payload size of dynamic SFI based on the configuration of the dynamic SFI mapping type and the dynamic SFI monitoring periodicity or rate. For example, if the dynamic SFI mapping is bit-mapping per slot, with two bits per slot for four possibilities of DL, UL, Unknown, and Reserved, and the monitoring periodicity is configured as once in every two slots, then the payload size of the dynamic SFI may be determined as 2 x 2 = 4 bits. The payload size of a dynamic SFI may also be signaled and configured separately by RRC signaling, higher layer signaling, or the like.

[00131] An implicit configuration of the table associated with dynamic SFI may also be utilized. For this configuration, mapping the content of the dynamic SFI to the slot format may be performed by configuring the mapping implicitly based on parameters that are configured by RRC signaling, higher layer signaling, or the like. In addition, the implicit configuration of the table associated with dynamic SFI may be based on SFI monitoring rate. For example, dynamic SFI monitoring periodicity of less than once per two slots may indicate that the slot format is similar for slots in the dynamic SFI monitoring period. In another example, the dynamic SFI monitoring periodicity may reduce dynamic SFI mappings.

[00132] In another configuration, implicit configuration of the table associated with dynamic SFI may be based on a combination of SFI monitoring rate and SFI payload size. In such a scenario, the combination of SFI monitoring rate and SFI payload size may implicitly determine the mapping of the dynamic SFI content to the format of the slots. For example, a dynamic SFI payload size of eight bits and SFI monitoring periodicity of once every two slots may implicitly indicate that the mapping of the dynamic SFI content to the format of slots is bit-map per half slot with four possibilities for each half slot. Furthermore, implicit indication of the mapping of the dynamic SFI content to the format of slots based on a combination of SFI monitoring rate and SFI payload size may be set by a pre-determined, fixed, or the like table.

[00133] In another configuration, implicit configuration of a table associated with dynamic SFI may be based on the number of DL/UL switching points or other properties of the slot format. In one example, properties of the slot format for a slot, a set of contiguous, non-contiguous slots, or the like may be indicated in a semi-static configuration included in RRC signaling, higher layer signaling, or the like. For example, it may be indicated that there are at most k DL/UL switching point(s) in the slot format for one slot or a set of slots and the content of the dynamic SFI may be mapped to the slot format according to that property indication by RRC, where k may be zero or a positive integer. In this example, implicit indication of the mapping of the dynamic SFI content to the format of slots based on the number of switching points or other properties of the slot format may be set by a table that is pre-determined, fixed, or the like. [00134] In another example, the indication of the dynamic slot format may be based on a semi-static SFI and the content of the dynamic SFI. Dynamic slot format of a slot or a set of slots may be based on the content of a semi-static SFI. For example, if the semi-static SFI for a slot or a set of slots indicates a combination of DL and "Unknown", then a table for the slot formats of that slot or set of slots may exclude UL and only includes DL and "Unknown".

[00135] Although features and elements are described above in particular combinations, one of ordinary skill in the art will appreciate that each feature or element can be used alone or in any combination with the other features and elements. In addition, the methods described herein may be implemented in a computer program, software, or firmware incorporated in a computer- readable medium for execution by a computer or processor. Examples of computer-readable media include electronic signals (transmitted over wired or wireless connections) and computer-readable storage media. Examples of computer-readable storage media include, but are not limited to, a read only memory (ROM), a random access memory (RAM), a register, 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.