SYSTEM AND METHOD FOR REFERENCE SIGNAL MEASUREMENT IN WIRELESS SYSTEMS - Patent application

Abstract

To provide systems, apparatuses, and methods for receiving downlink control information (DCI) that may include an indication of a reference measurement resource (RMR), receiving an indication of a measurement configuration, and receiving an indication of a feedback resource configuration.SOLUTION: A measurement report based on an indication of an RMR, an indication of a measurement configuration, and an indication of a feedback resource configuration may be generated and may be transmitted to a network device.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to wireless communications. [Background technology]

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application No. 62 / 315,405, filed March 30, 2016, U.S. Provisional Patent Application No. 62 / 334,788, filed May 11, 2016, and U.S. Provisional Patent Application No. 62 / 416,397, filed November 2, 2016, each of which is entitled "Systems and Methods for Reference Signal Measurements in Wireless Systems" and is hereby incorporated by reference in its entirety.

[0003] Cell-specific reference signals (CRS) may be used in wireless systems for channel estimation to perform coherent demodulation of physical channels, for collecting channel state information (CSI) for transmission modes (TM), and / or for higher layer measurements that may be used in cell selection and handover decisions. It may be desirable to reduce reference signal overhead to limit unwanted interference to neighboring transmission / reception points (TRPs) and / or to reduce power consumption at the TRPs. Summary of the Invention

[0004] This Summary is provided to introduce a selection of exemplary, non-limiting concepts disclosed in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features and / or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

[0005] A system, apparatus, and method are disclosed for receiving downlink control information (DCI), which may include an indication of a reference measurement resource (RMR), receiving an indication of a measurement configuration, and receiving an indication of a feedback resource configuration. A measurement report based on the indication of the RMR, the indication of the measurement configuration, and / or the indication of the feedback resource configuration may be generated and transmitted to a network device.

[0006] An indication of association of the RMR with at least one of a measurement configuration or a feedback resource configuration may be received. The DCI may include information that may be associated with one or more of a mobility-related measurement, a channel state information (CSI) measurement, a demodulation process, positioning, radio link monitoring, or cell collection. The DCI may also, or instead, include an indication of a change in an activation state of the RMR. The DCI may also, or instead, include information for scheduling a transmission.

[0007] The measurement configuration may include criteria that may be associated with a refined selection of an RMR instance and / or an RMR resource. The measurement configuration may also or instead include an indication of an RMR process and / or an RMR instance. The measurement configuration may also or instead include an indication of a measurement type and / or an indication of a measurement purpose. The measurement configuration may also or instead include an indication of a trigger criterion. A measurement report may be transmitted to the network device based on or in response to a decision based on the indication of the trigger criterion. [Brief description of the drawings]

[0008] The following detailed description of various non-limiting examples is given with reference to the accompanying drawings. For illustrative purposes, the drawings are provided to assist in the description of various non-limiting examples. The contemplated subject matter is not limited to the specific elements and / or means described or shown. Otherwise, without specific indication, the subject matter described herein is not contemplated as necessary and / or essential. The described examples may be employed in whole or in part in any combination. [Figure 1A]FIG. 1 is a system diagram of an example communication system in which one or more disclosed examples may be implemented. [Figure 1B] 1B is a system diagram of an example wireless transmit / receive unit (WTRU) that may be used within the example communications system shown in FIG. 1A. [Figure 1C] 1B is a system diagram of an example radio access network and an example core network that may be used within the example communication system shown in FIG. 1A. [Figure 1D] 1B is a system diagram of another example radio access network and another example core network that may be used within the example communication system shown in FIG. 1A. [Figure 1E] 1B is a system diagram of another example radio access network and another example core network that may be used within the example communication system shown in FIG. 1A. [Diagram 2] 1 is a graph illustrating an example channel bandwidth. [Diagram 3] 1 is a graph illustrating an exemplary spectrum allocation. [Figure 4] FIG. 2 is a diagram of an exemplary frame structure. [Diagram 5] FIG. 2 is a diagram of another exemplary frame structure. [Figure 6] FIG. 1 illustrates an example DCI configuration and activation / deactivation process. [Figure 7] FIG. 1 is a diagram of an example DCI configuration and resource request process. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] A detailed description of non-limiting examples is provided with reference to various figures. Although this description provides detailed examples of possible examples, it should be noted that the details are intended to be illustrative and in no way limit the scope of the application. Without further modification or characterization, the article "a" or "an" as used herein may be understood to mean, for example, "one or more" or "at least one". Also, the phrase "user equipment" (UE) as used herein may be understood to refer to a "wireless transmit / receive unit" (WTRU).

[0010] 1A is a diagram of an example communication system 100 in which one or more disclosed examples may be implemented. The communication system 100 may be a multiple access system that may provide content, such as voice, data, video, messaging, broadcast, etc., to multiple wireless users. The communication system 100 may enable multiple wireless users to access such content through sharing of system resources, including, but not limited to, 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), etc.

[0011] 1A, the communications system 100 may include wireless transmit / receive units (WTRUs) 102a, 102b, 102c, and / or 102d (which may be referred to generally or collectively herein as WTRUs 102), a radio access network (RAN) 103 / 104 / 105, a core network 106 / 107 / 109, a public switched telephone network (PSTN) 108, the Internet 110, and / or other networks 112, although the disclosed examples 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. For example, each of the WTRUs 102a, 102b, 102c, 102d may be configured to transmit and / or receive wireless signals and may be any of a user equipment (UE), a mobile station, a fixed subscriber unit, a mobile subscriber unit, a pager, a cellular telephone, a personal digital assistant (PDA), a smartphone, a laptop, a netbook, a personal computer, a wireless sensor, a consumer electronics, etc., or any combination thereof.

[0012] The communications system 100 may also include a base station 114a and a base station 114b. Each of the base stations 114a and 114b may be any type of device configured to wirelessly interface with at least one of the WTRUs 102a, 102b, 102c, and 102d to facilitate access to one or more communications networks, such as the core network 106 / 107 / 109, the Internet 110, and / or other networks 112. For example, each of the base stations 114a and 114b may be a base transceiver station (BTS), a Node B, an eNode B, a Home Node B, a Home eNode B, a site controller, an access point (AP), a wireless router, etc., or any combination thereof. Although the base stations 114a and 114b are each illustrated as a single element, it is contemplated that each of the base stations 114a and 114b may include any number of interconnected base stations and / or network elements.

[0013] The base station 114a may also be part of the RAN 103 / 104 / 105, which may include any number of 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 within a geographical area, sometimes referred to as a cell. The cells may be divided into cell sectors. For example, the cell associated with the base station 114a may be divided into three cell sectors. In an example, the base station 114a may include, for example, three transceivers, one transceiver for each sector of the cell associated with the base station 114a. In another example, the base station 114a may employ multiple-input multiple-output (MIMO) technology and utilize multiple transceivers for each sector of the cell associated with the base station 114a.

[0014] The base stations 114a and 114b may each communicate with one or more of the WTRUs 102a, 102b, 102c, and 102d over an air interface 115 / 116 / 117, which may be any suitable wireless communication link (e.g., radio frequency (RF), microwave, infrared (IR), ultraviolet (UV), visible light, etc.). The air interface 115 / 116 / 117 may be established using any suitable radio access technology (RAT).

[0015] 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, each of the base stations 114a and the WTRUs 102a, 102b, and 102c in the RAN 103 / 104 / 105 may implement a radio technology such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which may establish the air interface 115 / 116 / 117 using Wideband CDMA (WCDMA). WCDMA may include the use of 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).

[0016] In another example, the base station 114a and the WTRUs 102a, 102b, and 102c may implement a radio technology such as Evolved UMTS Terrestrial Radio Access (E-UTRA), which may establish the air interface 115 / 116 / 117 using Long Term Evolution (LTE) and / or LTE-Advanced (LTE-A).

[0017] In other examples, the base station 114a and the WTRUs 102a, 102b, and 102c may implement a wireless technology such as IEEE 802.16 (i.e., Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 IX, CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System for Mobile Communications (GSM), Enhanced Data Rates for GSM Evolution (EDGE), Edge of GSM (GERAN), etc.

[0018] The base station 114b in FIG. 1A may be, for example, a wireless router, a Home NodeB, a Home eNodeB, or an access point, and may utilize any suitable RAT to facilitate wireless connectivity in a local area, such as an office, a home, a vehicle, a campus, etc. In an example, the base station 114b and the WTRUs 102c and 102d may implement a radio technology such as IEEE 802.11 to establish a wireless local area network (WLAN). In another example, the base station 114b and the WTRUs 102c and 102d may implement a radio technology such as IEEE 802.15 to establish a wireless personal area network (WPAN). In yet another example, the base station 114b and the WTRUs 102c and 102d may utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, 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. The base station 114b may not be required to access the Internet 110 via the core network 106 / 107 / 109.

[0019] The RAN 103 / 104 / 105 may be in communication with a core network 106 / 107 / 109. The core network 106 / 107 / 109 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, and 102d. For example, the core network 106 / 107 / 109 may provide call control, billing services, mobile location services, prepaid calling, Internet connectivity, video distribution, etc., and / or perform high-level security functions, such as user authentication. The RAN 103 / 104 / 105 and / or the core network 106 / 107 / 109 may be in direct and / or indirect communication with other RANs, which may employ the same RAT as the RAN 103 / 104 / 105 and / or a different RAT. For example, in addition to being connected to the RAN 103 / 104 / 105, which may utilize E-UTRA radio technology, the core network 106 / 107 / 109 may also be in communication with another RAN that employs GSM radio technology.

[0020] The core network 106 / 107 / 109 may also act as a gateway for one or more of the WTRUs 102a, 102b, 102c, and 102d that may be used to access the PSTN 108, the Internet 110, and / or other networks 112. The PSTN 108 may include a circuit-switched telephone network that may 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 TCP, UDP, and / or 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 a core network connected to one or more RANs, each of which may employ the same RAT as the RANs 103 / 104 / 105 and / or a different RAT.

[0021] Some or all of the WTRUs 102a, 102b, 102c, and 102d in the communications system 100 may include multi-mode capabilities, e.g., each of the WTRUs 102a, 102b, 102c, and 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, which may employ a cellular-based wireless technology, and with a base station 114b, which may employ an IEEE 802 wireless technology.

[0022] 1B is a system diagram of an example WTRU 102, which may represent a WTRU such as any of WTRUs 102a, 102b, 102c, and 102d. As shown in FIG. 1B, 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 GPS chipset 136, and any of other peripherals 138. The WTRU 102 may include any subcombination of the above elements while remaining consistent with the disclosed examples. It is contemplated that each of the base stations 114a and 114b and / or any of the nodes that they may represent, such as, but not limited to, a base transceiver station (BTS), a Node B, a site controller, an access point (AP), a Home Node B, an evolved Home Node B (eNodeB), a Home evolved Node B (HeNB), a Home evolved Node B gateway, and a proxy node, among others, may include any or all of the elements shown in FIG. 1B and described herein.

[0023] 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, one or more ASICs, one or more FPGA circuits, other types of integrated circuits (ICs), state machines, etc., or any combination thereof. 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. Although FIG. 1B depicts the processor 118 and the transceiver 120 as separate components, it is contemplated that the processor 118 and the transceiver 120 may be incorporated together in an electronic package or chip.

[0024] The transmit / receive element 122 may be configured to transmit signals to or receive signals from a base station (e.g., base station 114a) via the air interface 115 / 116 / 117. For example, in an example, the transmit / receive element 122 may be an antenna configured to transmit and / or receive RF signals. In another example, the transmit / receive element 122 may be an emitter / detector configured to transmit and / or receive, for example, IR, UV, or visible light signals. In another example, the transmit / receive element 122 may be configured to transmit and / or receive both RF and light signals. The transmit / receive element 122 may be configured to transmit and / or receive any combination of wireless signals.

[0025] 1B may be a single element, the WTRU 102 may include any number of transmit / receive elements 122. The WTRU 102 may employ MIMO technology. In an example, the WTRU 102 may include two or more transmit / receive elements 122 (e.g., multiple antennas) for transmitting and / or receiving wireless signals over the air interface 115 / 116 / 117.

[0026] The transceiver 120 may be configured to modulate signals that may be transmitted by the transmit / receive element 122 and / or demodulate signals that may be received by the transmit / receive element 122. The WTRU 102 may have multi-mode capabilities. The transceiver 120 may include multiple transceivers that may enable the WTRU 102 to communicate via multiple RATs, such as, for example, UTRA and / or IEEE 802.11.

[0027] The processor 118 of the WTRU 102 may be coupled to and / or receive user input data from the speaker / microphone 124, the keypad 126, and / or the display / touchpad 128 (which may be, for example, 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. The processor 118 may access information from and / or 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 RAM, ROM, a hard disk, and / or other types of memory storage devices. The removable memory 132 may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, or the like, or any combination thereof. The processor 118 may access information from and / or store data in memory that is not physically located in the WTRU 102, such as memory located on a server or memory located on a home computer.

[0028] The processor 118 may receive power from the power source 134 and may be configured to supply power to and / or control other components of 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., or any combination thereof.

[0029] 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 position of the WTRU 102. In addition to, or in lieu of, the location information provided by the GPS chipset 136, the WTRU 102 may receive location information over the air interface 115 / 116 / 117 from a base station (e.g., base stations 114a, 114b) and / or determine its location based on the timing of signals received from two or more nearby base stations. It will be appreciated that the WTRU 102 may collect location information by way of any suitable location determination method while remaining consistent with the disclosed examples.

[0030] The processor 118 may further be coupled to peripherals 138, which may include one or more software and / or hardware modules that may provide additional features, functionality and / or connectivity (wired and / or wireless). For example, the peripherals 138 may include an accelerometer, an electronic compass, a satellite transceiver, a digital camera (capable of capturing photos and / or videos), a USB port, a vibration device, a television transceiver, a hands-free headset, a Bluetooth module, a frequency modulation (FM) radio unit, a digital music player, a media player, a video game player module, an Internet browser, etc., or any combination thereof.

[0031] 1C is a system diagram of the RAN 103 and the core network 106, according to an example. The RAN 103 may employ UTRA radio technology to communicate with the WTRUs 102a, 102b, and / or 102c over the air interface 115. The RAN 103 may also be in communication with the core network 106. The RAN 103 may include Node Bs 140a, 140b, and / or 140c, each of which may include one or more transceivers for communicating with the WTRUs 102a, 102b, and / or 102c over the air interface 115. The Node Bs 140a, 140b, and 140c may each be associated with a cell within the RAN 103. The RAN 103 may include one or both of the RNCs 142a and 142b, and / or any other RNCs. The RAN 103 may include any number of Node Bs and RNCs while remaining consistent with the contemplated example.

[0032] Node Bs 140a and 140b may be in communication with RNC 142a. Node Bs 140c may be in communication with RNC 142b. Node Bs 140a and 140b may be in communication with RNC 142a via an Iub interface. Node Bs 140c may be in communication with RNC 142b via an Iub interface. RNCs 142a and 142b may be in communication with each other via an Iur interface. Each of RNCs 142a and 142b may be configured to control the respective Node Bs 140a, 140b, and 140c to which the RNC is connected. Each of RNCs 142a and 142b may also or instead be configured to perform and / or support other functionality, such as outer loop power control, load control, admission control, packet scheduling, handover control, macro diversity, security functions, data encryption, and the like, or any combination thereof.

[0033] 1C may include a media gateway (MGW) 144, a mobile switching center (MSC) 146, a serving GPRS support node (SGSN) 148, and / or a gateway GPRS support node (GGSN) 150. Although each of the above elements is shown as part of the core network 106, any one or more of these elements may be owned and / or operated by an entity other than the operator of the core network 106.

[0034] The RNC 142a in the RAN 103 may be connected to an MSC 146 in the core network 106 via an IuCS interface. The MSC 146 may be connected to the MGW 144. The MSC 146 and MGW 144 may provide the WTRUs 102a, 102b, and / or 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, and / or 102c and legacy landline communication devices.

[0035] The RNC 142a in the RAN 103 may be connected to an SGSN 148 in the core network 106 via an IuPS interface. The SGSN 148 may be connected to a GGSN 150. The SGSN 148 and / or GGSN 150 may provide the WTRUs 102a, 102b, and / or 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, and / or 102c and IP-enabled devices.

[0036] As mentioned above, the core network 106 may also be connected to other networks 112, which may include other wired and / or wireless networks that may be owned and / or operated by other service providers.

[0037] 1D is a system diagram of the RAN 104 and the core network 107, according to an example. The RAN 104 may employ E-UTRA radio technology to communicate with the WTRUs 102a, 102b, and / or 102c over the air interface 116. The RAN 104 may also, or instead, be in communication with the core network 107.

[0038] The RAN 104 may include eNodeBs 160a, 160b, and / or 160c, although it is contemplated that the RAN 104 may include any number of eNodeBs while remaining consistent with the disclosed examples. The eNodeBs 160a, 160b, and 160c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, and / or 102c over the air interface 116. In an example, one or more of the eNodeBs 160a, 160b, and 160c may implement MIMO technology. The eNodeB 160a may use multiple antennas, for example, to transmit wireless signals to and / or receive wireless signals from the WTRU 102a.

[0039] Each of the eNodeBs 160a, 160b, and 160c may be associated with a cell and / or configured to handle radio resource management decisions, handover decisions, scheduling of users in the uplink and / or downlink, etc., or any combination thereof. The eNodeBs 160a, 160b, and / or 160c may each communicate with each other over an X2 interface.

[0040] 1D may include a mobility management gateway (MME) 162, a serving gateway 164, and / or a packet data network (PDN) gateway 166. Each of these elements may be part of the core network 107, although it is contemplated that any one or more of these elements may be owned and / or operated by an entity other than a core network operator.

[0041] The MME 162 may be connected to one or more of the eNodeBs 160a, 160b, and 160c in the RAN 104 via an S1 interface and / or may act as a control node. For example, the MME 162 may be responsible for authenticating users of one or more of the WTRUs 102a, 102b, and 102c, bearer activation / deactivation, selecting a serving gateway during initial attach of the WTRUs 102a, 102b, and / or 102c, etc., or any combination thereof. The MME 162 may provide a control plane function for switching between the RAN 104 and other RANs, which may employ other radio technologies, such as GSM or WCDMA.

[0042] The serving gateway 164 may be connected to one or more of the eNodeBs 160a, 160b, and 160c in the RAN 104 via an S1 interface. The serving gateway 164 may route and / or forward user data packets to and / or from the WTRUs 102a, 102b, and / or 102c. The serving gateway 164 may also, or instead, perform other functions, such as anchoring the user plane during inter-eNodeB handover, triggering paging when downlink data is available for the WTRUs 102a, 102b, and / or 102c, managing and / or storing context of the WTRUs 102a, 102b, and / or 102c, etc., or any combination thereof.

[0043] The serving gateway 164 may be connected to a PDN gateway 166, which may provide the WTRUs 102a, 102b, and / or 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, and / or 102c and IP-enabled devices.

[0044] The core network 107 may facilitate communications with other networks. For example, the core network 107 may provide the WTRUs 102a, 102b, and / or 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, and / or 102c and legacy landline communications devices. The core network 107 may include and / or communicate with an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that may act as an interface between the core network 107 and the PSTN 108. The core network 107 may provide the WTRUs 102a, 102b, and / or 102c with access to other networks 112, which may include other wired and / or wireless networks that may be owned and / or operated by other service providers.

[0045] 1E is a system diagram of the RAN 105 and the core network 109, according to an example. The RAN 105 may be an Access Service Network (ASN) that may employ IEEE 802.16 wireless technology to communicate with one or more of the WTRUs 102a, 102b, and 102c over the air interface 117. Communication links between different functional entities of the WTRUs 102a, 102b, and 102c, the RAN 105, and the core network 109 may be defined as reference points.

[0046] The RAN 105 may include base stations 180a, 180b, and / or 180c and / or an ASN gateway 182, although it is contemplated that the RAN 105 may include any number of base stations and / or ASN gateways while remaining consistent with the disclosed examples. The base stations 180a, 180b, and 180c may each be associated with a cell in the RAN 105 and / or each include one or more transceivers for communicating with the WTRUs 102a, 102b, and / or 102c over the air interface 117. In an example, the base stations 180a, 180b, and / or 180c may implement MIMO technology. The base station 180a may use multiple antennas, for example, to transmit wireless signals to and / or receive wireless signals from the WTRU 102a. The base stations 180a, 180b, and / or 180c may also provide mobility management functions, such as handoff triggering, tunnel establishment, radio resource management, traffic classification, quality of service (QoS) policy enforcement, and / or any combination thereof. The ASN gateway 182 may act as a traffic aggregation point and / or be responsible for paging, caching of subscriber profiles, routing to the core network 109, and / or any combination thereof.

[0047] The air interface 117 between the WTRUs 102a, 102b, and / or 102c and the RAN 105 may be defined as an R1 reference point, which may implement the IEEE 802.16 specification. One or more of the WTRUs 102a, 102b, and / or 102c may establish a logical interface with the core network 109. The logical interface between the WTRUs 102a, 102b, and / or 102c and the core network 109 may be defined as an R2 reference point (not shown), which may be used for authentication, authorization, IP host configuration management, and / or mobility management, or any combination thereof.

[0048] The communication link between any of the base stations 180a, 180b, and 180c may be defined as an R8 reference point, which may include protocols for facilitating WTRU handover and / or transfer of data between the base stations. The communication link between the base stations 180a, 180b, and / or 180c and the ASN gateway 182 may be defined as an R6 reference point. The R6 reference point may include protocols for facilitating mobility management based on mobility events associated with one or more of the WTRUs 102a, 102b, and 102c.

[0049] The RAN 105 may be connected to a core network 109. A communication link between the RAN 105 and the core network 109 may be defined as an R3 reference point that may include one or more protocols, for example, to facilitate data transfer and / or mobility management capabilities. The core network 109 may include one or more of a Mobile IP Home Agent (MIP-HA) 184, an Authentication, Authorization, and Accounting (AAA) server 186, and a gateway 188. Although each of such elements is illustrated in FIG. 1E as part of the core network 109, it is contemplated that any one or more of these elements may be owned and / or operated by an entity other than a core network operator.

[0050] The MIP-HA 184 may be responsible for IP address management and may enable the WTRUs 102a, 102b, and / or 102c to roam between different ASNs and / or different core networks. The MIP-HA 184 may provide the WTRUs 102a, 102b, and / or 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, and / or 102c and IP-enabled devices. The AAA server 186 may be responsible for supporting user authentication and / or user services. The gateway 188 may facilitate interworking with other networks. For example, the gateway 188 may provide the WTRUs 102a, 102b, and / or 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, and / or 102c and legacy landline communication devices. The gateway 188 may provide the WTRUs 102a, 102b, and / or 102c with access to other networks 112, which may include other wired and / or wireless networks that may be owned and / or operated by other service providers.

[0051] It is contemplated that the RAN 105 may be connected to other ASNs and / or the core network 109 may be connected to other core networks. A communication link between the RAN 105 and one or more other ASNs may be defined as an R4 reference point, which may include protocols for coordinating mobility of the WTRUs 102a, 102b, and / or 102c between the RAN 105 and such other ASNs. A communication link between the core network 109 and one or more other core networks may be defined as an R5 reference point, which may include protocols for facilitating interworking between one or more home core networks and one or more visited core networks.

[0052] In an LTE example, multiple downlink reference signals (RS) may be transmitted for one or more purposes. The WTRU may receive cell-specific reference signals (CRS) from the PCell and / or SCell. Such CRS may be transmitted in a downlink subframe in a frequency division duplex (FDD) example. Alternatively, or additionally, such CRS may be transmitted in a downlink subframe and / or a downlink pilot time slot (DwPTS) in a time division duplex (TDD) example. One or more CRS may also or instead be transmitted in one or more resource blocks in the frequency domain.

[0053] In LTE, as many as eight resource elements (REs) per antenna port per physical resource block (PRB) may be used for transmission of one or more CRSs. Note that in other examples, fewer or more REs per antenna port per PRB may be used for transmission of one or more CRSs.

[0054] The CRS may assist one or more WTRUs in performing channel estimation for coherent demodulation of one or more downlink physical channels. In an example, one or more WTRUs may not use a CRS for demodulation of some downlink channels, such as a physical multicast channel (PMCH), a physical downlink shared channel (PDSCH), and / or an enhanced physical downlink shared channel (EPDCCH). The CRS may be used to collect channel state information (CSI) for one or more transmission modes (TM), e.g., transmission modes 1-8. The CRS may be used for higher layer measurements, such as as a basis for cell selection and / or as a basis for handover decisions.

[0055] A WTRU-specific reference signal associated with a PDSCH may be referred to as a demodulation reference signal (DM-RS). A DM-RS, which may be transmitted using one or more of the same resources that may be used for an associated PDSCH, may be used to enable channel estimation for coherent demodulation of such PDSCH (e.g., for transmission modes 7-10) and / or for demodulation of one or more other PDSCHs. A DM-RS, which may be associated with a PDSCH based on one or more of any type of configuration, indication, and / or rule (e.g., rather than being associated with a PDSCH based on use of one or more of the same resources), may be used with the PDSCH specified in such configuration, indication, and / or rule.

[0056] The DM-RS may also, or instead, be used to enable demodulation of the EPDCCH channel. The DM-RS may be transmitted on one or more antenna ports, each of which may be associated with several layers used for transmission of the PDSCH and / or EPDCCH. The DM-RS may be transmitted on one or more physical resource blocks. In an example, one or more DM-RS may be transmitted on one or more physical resource blocks to which the corresponding PDSCH and / or EPDCCH may be mapped. In an example, one or more DM-RS may be mapped to a number of REs per PRB, such as 12 REs per PRB. Alternatively, or in addition, one or more DM-RS may use an orthogonal cover code (OCC) to enable up to a number of ports, such as eight ports, which may be transmitted on a number of REs per PRB, such as 24 REs per PRB.

[0057] A CSI reference signal (CSI-RS) resource may be used to enable one or more WTRUs in one or more TMs, such as WTRUs in TMs 9-10, in collecting CSI. The CSI-RS resource may have a lower time and / or frequency density than the CRS. For example, the periodicity of the CSI-RS resource may be, for example, 80 subframes, where two REs per antenna port per PRB may be used for the CSI-RS resource.

[0058] A WTRU in a TM, such as a WTRU in TM10, may be configured with channel state information interference measurement (CSI-IM). The CSI-IM configuration may indicate to the WTRU resources on which the WTRU may expect zero power transmissions from the serving cell. Such CSI-IM resources may be used by the WTRU to make measurements, for example, based on the assumption that the measured signal may be interference plus noise.

[0059] The WTRU may be configured to make CSI measurements on the CRS and / or CSI-RS, depending on the transmission mode (TM) in some examples. Such measurements may include one or more of a rank indication (RI), a channel quality indication (CQI), a precoder matrix indication (PMI), and a precoding type indicator (PTI). The WTRU may report such CSI measurements either in one or more physical uplink control channel (PUCCH) resources (e.g., for periodic CSI reporting) and / or in one or more physical uplink shared channel (PUSCH) resources (e.g., for UCI on the PUSCH or for aperiodic CSI reporting).

[0060] Either or both of periodic and aperiodic CSI reporting may be configured using one or more of a number of reporting modes. Such a mode may indicate whether wideband CQI feedback reporting may be used, WTRU-selected subband CQI feedback reporting may be used, and / or higher layer configured subband CQI feedback reporting may be used (e.g., in an aperiodic reporting example). The reporting mode may indicate whether no PMI feedback reporting may be used, a single PMI feedback reporting may be used, or multiple PMI feedback reporting may be used (e.g., in an aperiodic reporting example).

[0061] For CQI calculation, the WTRU may determine an interference level. The manner in which the WTRU determines the interference level may depend on the implementation. For example, the WTRU may determine the interference level as noise on a cell-specific reference signal. The WTRU may average the interference level over multiple subframes. CSI-IM may be used as a resource that the WTRU may use to measure the interference level.

[0062] The WTRU may be configured with multiple CSI processes, e.g., to support coordinated multipoint (CoMP). The CSI processes may include a combination of CSI-RS and CSI-IM. The WTRU may be configured to report separate CSI for each CSI process, in some examples, periodically and / or aperiodically.

[0063] The WTRU may be configured to perform cell selection and / or enable handover. Such a WTRU may be configured in Radio Resource Control (RRC) with measurement reports of measurements such as, for example, Reference Signal Received Power (RSRP), Reference Signal Strength Indicator (RSSI), and / or Reference Signal Received Quality (RSRQ). The WTRU may report such measurements in an RRC measurement report. The WTRU may be configured, for example, to constantly measure multiple cells. Based on whether the measurements meet a configurable condition, the WTRU may be triggered to report such measurements.

[0064] In an example, new radio (NR) access may be used in a fifth realization of mobile communications, such as 5G. NR may be used herein to refer to 5G radio access protocols. Various use cases contemplated for NR may contribute to determining the capabilities and / or requirements for a system that implements NR access. Contemplated approaches for design of a system, such as a 5G system, may correspond at least in part to NR access technologies that may meet 5G requirements, without limiting the applicability of the disclosed examples to such systems.

[0065] The air interface may enable one or more of improved broadband performance (e.g., IBB), industrial control and communications (e.g., ICC), vehicular applications (e.g., V2X), and large-scale machine-type communications, (e.g., mMTC). For example, NR may be designed to handle and / or multiplex IBB, ICC, V2X, and / or mMTC communications.

[0066] Support may be provided for baseband filtering of frequency domain waveforms, which may enable aggregation of at least 150-200 MHz of total spectrum within the RF transceiver path.

[0067] Aggregation of spectrum across relatively widely separated operating bands (e.g., 900 MHz, 3.5 GHz) may use multiple RF transceiver chains in some examples due to antenna size requirements and / or amplifier optimization design constraints. For example, a WTRU implementation may include three separate RF transceiver paths, e.g., a first path below 1 GHz, a second path for the 1.8-3.5 GHz frequency range, and a third path for the 4-6 GHz frequency range.

[0068] Native built-in support for massive MIMO antenna configurations may be a secondary requirement.

[0069] An example IBB may use multiple frequency bands, each of which may have a spectrum of varying size. Such bands may be aggregated to achieve data rates on the order of tens of Mbps (e.g., at the cell edge) up to peak data rates of several Gbps (e.g., up to 8 Gbps), with typical rates that may be on the order of hundreds of Mbps.

[0070] Ultra-low transmission latency may be achieved, for example, by supporting one or more transmission time intervals (TTIs) between 100 μs and 250 μs, and may be supported, for example, by air interface latency as low as 1 ms round trip time (RTT). Support for ultra-low access latency (e.g., time from initial system access to completion of transmission of the first user plane data unit) may also or instead be supported, for example, by implementations that use ICC and / or V2X and / or may specify end-to-end (e2e) latency of, for example, less than 10 ms.

[0071] Ultra-reliable transmissions may be supported, for example, by providing transmission reliability that may be lower than that which may be found in legacy LTE systems. Support for mobility with speeds in the range of 0-500 km / h may be achieved in examples. For example, implementations using ICC and / or V2X may be implemented in the 10e -6 A packet loss rate of less than 100% may be specified.

[0072] Support for machine type communication (MTC) operation (e.g., narrowband operation) may be provided. The air interface may support narrowband operation (e.g., using less than 200KHz), extended battery life (e.g., up to 15 years of autonomy), and / or minimal communication overhead for small and / or infrequent data transmissions (e.g., low data rates in the range of 1-100kbps with access latencies of seconds to hours). Support for a massive MTC (mMTC) instance may be provided by a narrowband operation implementation. A very large number of MTC devices (e.g., up to 200k / km2) may be supported, although the associated link budget may be comparable to that of LTE extended coverage.

[0073] The system design may enable flexible spectrum utilization, deployment strategies, and / or operations. One or more operations may use spectrum of varying sizes and / or may include aggregation of non-contiguous carriers in the same and / or different frequency band(s) (e.g., licensed and / or unlicensed frequency bands). Narrowband and / or wideband operation, different duplexing methods (e.g., in a TDD example, dynamically variable downlink (DL) / uplink (UL) allocation), variable TTI lengths, scheduled and / or unscheduled transmissions, synchronous and / or asynchronous transmissions, separation of user plane from control plane, and / or multi-node connectivity may be supported.

[0074] The system may integrate with one or more legacy Universal Terrestrial Access Networks (UTRAN), Evolved Universal Terrestrial Access Networks (EUTRAN), Evolved Packet Core (EPC) / Core Networks (CN), and / or associated aspects. The system may integrate with and / or operate with one or more legacy interfaces and / or evolved interfaces associated therewith. The system may be in communication with a legacy CN (e.g., by using an S1 interface, a non-access stratum, etc.) and / or in communication with one or more legacy eNodeBs (e.g., by using an X2 interface, which may include dual connectivity with an LTE entity). Such an example system may enable legacy aspects, such as support for existing QoS and / or security mechanisms.

[0075] Elements of the disclosed examples may be included in LTE Evolution examples, for example, to provide backward compatibility of some or all components. For example, TTIs shorter than LTE slots (e.g., 0.5 ms) may use waveforms different from those used in LTE Evolution systems to enable ultra-low latency. For example, the physical layer (DL and / or UL) may be operated in TDM and / or FDM, for example, with LTE. Functionality that may be supported by legacy systems may be provided by enabling device-to-device (D2D) and / or sidelink functionality, licensed-assisted access (LAA) operation using listen-before-talk (LBT), and / or support for relaying.

[0076] OFDM may be used as a basic signal format for data transmission in LTE and / or IEEE 802.11. OFDM may divide the spectrum into multiple parallel orthogonal subbands. Each subcarrier may be shaped using a rectangular window in the time domain, which may lead to synchronously shaped subcarriers in the frequency domain. OFDMA examples may have perfect frequency synchronization and tight management of uplink timing alignment within the duration of the cyclic prefix, for example, to maintain orthogonality between signals and / or to minimize inter-carrier interference. Such synchronization may not be used in systems where a WTRU may be connected to multiple access points simultaneously. For example, in the presence of aggregation of fragmented spectrum for WTRU transmissions, power reduction may be applied to uplink transmissions to comply with the spectrum emission requirements of adjacent bands.

[0077] Aspects of traditional OFDM (e.g., Cyclic Prefix (CP) OFDM (CP-OFDM)) may be addressed by more stringent RF requirements. Such examples may be used when operating with large amounts of contiguous spectrum that may not require aggregation. CP-based OFDM transmission schemes may lead to, for example, a downlink physical layer similar to that of legacy systems if modifications to pilot signal density and location are implemented.

[0078] Conventional OFDM may be considered as a candidate for the downlink transmission scheme, although other waveform candidates may be used.

[0079] The downlink transmission scheme may be based on a multicarrier waveform, which may be characterized by high spectral suppression (e.g., lower sidelobes and / or lower out-of-band (OOB) emissions). Multicarrier (MC) waveform candidates may include Orthogonal Frequency Division Multiplexing / Offset Quadrature Amplitude Modulation (OFDM / OQAM) and Universal Filter Multicarrier (UFMC) (e.g., Universal Filter OFDM (UF-OFDM)). A multicarrier modulation waveform may divide a channel into one or more subchannels and modulate data symbols on subcarriers in such subchannels.

[0080] In an OFDM-OQAM example, a filter may be applied to the OFDM signal in the time domain for each subcarrier to reduce OOB emissions. In an example, the use of OFDM-OQAM may result in very low interference for adjacent bands, may not use large guard bands, and may not use a cyclic prefix. An OFDM-OQAM example may be sensitive to multipath effects and / or high delay spread with respect to orthogonality, which may complicate equalization and / or channel estimation.

[0081] In a UFMC (UF-OFDM) example, a filter may be applied to the OFDM signal in the time domain to reduce OOB emissions. Filtering may be applied per subband to use the spectrum fragment. OOB emissions in the unused spectrum fragment(s) in the band may remain as high as OOB emissions in conventional OFDM. For example, UF-OFDM may improve over OFDM at the edges of the filtered spectrum but may not improve in the spectrum holes.

[0082] Multiplexing in frequency of signals with non-orthogonal properties (such as different subcarrier spacing) may be implemented. Additionally or alternatively, coexistence of asynchronous signals may be used. Such examples may not require complex interference cancellation receivers. Aggregation of spectrum fragments in baseband processing may be an alternative to systems that aggregate spectrum fragments as part of RF processing.

[0083] Coexistence of different waveforms within the same band may be used, for example, to support mMTC narrowband operation (e.g., using Single Carrier Multiple Access (SCMA)). The same band may support a combination of different waveforms, e.g., CP-OFDM, OFDM-OQAM, and / or UF-OFDM, for any or all of the disclosed aspects and / or for either or both of the downlink and uplink transmissions. Such waveform coexistence may be used, for example, with transmissions that may use different types of waveforms between different WTRUs and / or transmissions that may use different types of waveforms with the same WTRU, either simultaneously, with some overlap, and / or consecutively in the time domain.

[0084] Hybrid types of waveforms may be supported, such as waveforms and / or transmissions that may support at least one of possibly varying cyclic prefix (CP) duration (e.g., from one transmission to another), combinations of CP and low power tails (e.g., zero tails), forms of hybrid guard intervals (e.g., using a low power CP and an adaptive low power tail), and the like, as well as any combination thereof. Such hybrid types of waveforms may support dynamic variation and / or control of further aspects, such as application of filtering. For example, hybrid types of waveforms may help determine whether filtering may be applied at the edge of the spectrum that may be used for reception of transmission(s) for a given carrier frequency, at the edge of the spectrum used for reception of transmissions associated with a specific Spectral Operation Mode (SOM), per subband, and / or per group thereof. The uplink transmission scheme may use the same or different waveforms as those used for downlink transmissions. Multiplexing of transmissions to and / or from various WTRUs in the same cell may be based on FDMA and / or TDMA.

[0085] Spectral flexibility may enable deployment in different frequency bands with different characteristics, which may include different duplex configurations and / or different and / or variable sizes of the available spectrum, which may include contiguous and / or non-contiguous spectrum allocation in the same and / or different bands. Variable timing aspects may be supported. Support for multiple TTI lengths and / or asynchronous transmission may be provided.

[0086] TDD and / or FDD duplexing may be supported. In FDD operation, supplemental downlink operation may be supported using spectrum aggregation. FDD operation may support either or both full-duplex and half-duplex FDD operation. For TDD operation, the DL / UL allocation may be dynamic. For example, the DL / UL allocation may not be based on a fixed DL / UL frame configuration. The length of the DL and / or UL transmission interval may be set for each transmission opportunity.

[0087] The transmission bandwidths on the uplink and downlink may differ from one another, for example, the bandwidth of each of the uplink and downlink may range independently from a nominal system bandwidth to a maximum value corresponding to the system bandwidth.

[0088] In single carrier operation, the system bandwidth may include 5, 10, 20, 40, and / or 80 MHz. The system bandwidth may be any bandwidth in a given range, for example, from a few MHz to 160 MHz (or more). The nominal bandwidth may have one or more fixed values. Narrowband transmissions up to a specified frequency, such as 200 KHz, may be supported within the operating bandwidth for MTC devices.

[0089] FIG. 2 illustrates an example transmission bandwidth 200. As used herein, a "system bandwidth" may refer to the maximum portion of spectrum that may be managed by a network for a given carrier, such as system bandwidth 210 in FIG. 2. For such a carrier, the portion that a WTRU may minimally support for cell collection, measurements, and / or initial access to the network may correspond to a nominal system bandwidth, such as nominal system bandwidth 220 in FIG. 2. A WTRU may be configured with a channel bandwidth that may be within the entire system bandwidth. For example, a WTRUx as illustrated in FIG. 2 may be configured with a channel bandwidth 230 that may be a 10 MHz bandwidth that includes the nominal system bandwidth 220. In another example, a WTRUy as illustrated in FIG. 2 may be configured with a channel bandwidth 240 that may be all of the system bandwidth 210, including the nominal system bandwidth 220. Some or all of the channel bandwidth utilized by the WTRU may support NR access.

[0090] Each of the channel bandwidths 230 and 240 includes the nominal system bandwidth 220, however, the configured channel bandwidth of a WTRU may or may not include a nominal portion of the system bandwidth, as shown in the example transmission bandwidth 200 of Figure 2. For example, although the bandwidths 230 and 240 include the nominal system bandwidth 220, a WTRUz as shown in Figure 2 may be configured with a channel bandwidth 250, which may not include the nominal system bandwidth 220.

[0091] One or more sets of RF requirements for maximum operating bandwidth in a band may be met without the introduction of additional allowed channel bandwidth for that operating band, which may enable bandwidth flexibility. Baseband filtering of frequency domain waveforms may be supported. The physical layer may be band agnostic and / or may support operation in licensed bands, e.g., below 5 GHz, and / or in unlicensed bands, e.g., in the range of 5-6 GHz. An LBT CAT4-based channel access framework, which may be similar to LTE LAA, may be supported, e.g., in operation in unlicensed bands.

[0092] The downlink control channels and / or signals may support FDM operation. The WTRU may collect downlink carriers, for example, by receiving transmissions using a nominal portion of the system bandwidth, where the WTRU may not initially receive a transmission covering the entire bandwidth that may be managed by the network for the associated carrier.

[0093] The downlink data channel may be allocated on a bandwidth that may or may not correspond to the nominal system bandwidth. For example, the bandwidth to which the downlink data channel may be allocated may be determined without any restrictions other than being within the WTRU's configured channel bandwidth. In an exemplary, non-limiting example, the network may operate a carrier with a 12 MHz system bandwidth using a 5 MHz nominal bandwidth that may allow devices supporting at most a 5 MHz maximum RF bandwidth to acquire and / or access the system, while allocating +10 to -10 MHz of the carrier frequency to other WTRUs that may support up to 20 MHz worth of channel bandwidth, for example.

[0094] 3 shows a chart 300 illustrating an example spectrum allocation including a system bandwidth 310 and a nominal system bandwidth 315. Different subcarriers may be assigned to different operating modes. Such operating modes may be referred to as "spectral operating modes" or "SOMs." FIG. 3 shows example subcarriers 320 and 330. Subcarrier 320 may be assigned to a different SOM than the SOM associated with subcarrier 330.

[0095] Different SOMs may be used to meet different requirements for different transmissions. The SOM may include, and / or be characterized by, and / or be defined by, and / or be associated with, one or more of subcarrier spacing, symbol length, TTI length, and reliability aspects (such as hybrid automatic repeat request (HARQ) processing aspects). The SOM may also or instead include, and / or be characterized by, and / or be defined by, and / or be associated with, one or more of a particular secondary control channel, a particular waveform, any physical layer aspects. For example, an LTE signal may correspond to a first SOM. A first type of NR transmission may correspond to a second SOM. In an example, NR may support transmissions from multiple SOMs, e.g., a first SOM for NR supporting a massive broadband type use case, a second SOM for NR supporting an ultra-reliable low latency communication (URLLC) type use case, a third SOM for NR to support an mMTC type use case, etc. SOM may be used to refer to a particular waveform and / or may relate to processing aspects, such as those that may support coexistence of different waveforms in the same carrier using FDM and / or TDM. Similarly, SOM may be used where coexistence of FDD operation in a TDD band may be supported, for example, in a TDM fashion or similar implementation. As shown in FIG. 3, carriers / portions of spectrum may be associated with variable transmission characteristics, for example, to support transmissions associated with different SOMs at various times.

[0096] In single carrier operation, spectrum aggregation may be supported. The WTRU may support transmission and / or reception of multiple transport blocks on contiguous and / or non-contiguous sets of physical resource blocks (PRBs) within the same operating band. A single transport block may be mapped to a separate set of PRBs. Concurrent transmissions associated with different SOM requirements may be supported.

[0097] Multi-carrier operation may be supported. Contiguous and / or non-contiguous spectrum blocks may be used within the same operating band and / or across two or more operating bands. Spectrum blocks using different modes (e.g., FDD and TDD) and / or using different channel access methods (e.g., licensed and unlicensed band operation) may be aggregated. The WTRU's multi-carrier aggregation may be configured, reconfigured, and / or dynamically changed. Due to efficient baseband filtering in the frequency domain, in some examples, RF specification work to support additional channels and / or band combinations may not be used.

[0098] Downlink and uplink transmissions may be organized into radio frames, which may be characterized by one or more fixed aspects (e.g., location of downlink control information) and one or more variable aspects (e.g., transmission timing, supported types of transmissions). A basic time interval (BTI) may be expressed in terms of an integer number of one or more symbols. The symbol duration may be a function of the subcarrier spacing applicable to the time-frequency resource. In an FDD system, the subcarrier spacing is determined by the number of uplink carrier frequencies f for a given frame. UL and downlink carrier frequency f DL The number of sigma-based filters may vary between 0 and 1.

[0099] The transmission time interval (TTI) may be the minimum time between successive transmissions that can be supported by the system. Each successive transmission is transmitted over the downlink (TTIDL ) and for the uplink transceiver (UL TRx), and may exclude the preamble. Each successive transmission may include control information (e.g., downlink control information (DCI) for the downlink, uplink control information (UCI) for the uplink). The TTI may be expressed in terms of an integer number of one or more BTIs. The BTIs may be unique and / or associated with a SOM. The frame duration may include, but is not limited to, 100 μs, 125 μs (1 / 8 ms), 142.85 μs (e.g., 1 / 7 ms may be two nCP LTE OFDM symbols), and / or 1 ms. The one or more frame durations may be selected to enable alignment with a legacy LTE timing structure.

[0100] A frame is a set of associated carrier frequencies, e.g., f for TDD. UL+DL and f for FDD DL A fixed duration t may precede a downlink data transmission (DL TRx) for dci It may start with a DCI that may have:

[0101] Frame structure 400 of FIG. 4 illustrates an example frame structure that may be used in a TDD duplexing example. The TDD duplexing example may use a frame that may consist of both a downlink portion (DCI and DL TRx) and an uplink portion (UL TRx), such as frame 410, which may include DCI 411, DL TRx 412, and UL TRx 413. Also illustrated in FIG. 4 is frame 420, which may include DCI 421, DL TRx 422, and UL TRx 423. The TDD duplexing example may also, or instead, use a frame that may consist of a downlink portion (DCI and DL TRx) rather than an uplink portion (UL TRx). A switching gap (swg), such as swg 414 and swg 424, may precede the uplink portion of the frame, for example, for a frame of a given configuration.

[0102] A TDD example may support D2D, V2X, and / or sidelink operations in a frame by including the respective downlink control and / or forward transmissions in the DCI+DL TRx portion of such a frame (e.g., if semi-static allocation of the respective resources is used) or in the DL TRx portion of such a frame (e.g., in the case of dynamic allocation). The respective reverse transmissions may be included in the UL TRx portion.

[0103] Frame structure 500 of FIG. 5 illustrates an example frame structure that may be used in an FDD duplexing example and may use frames that may include a downlink reference TTI and / or one or more TTIs for the uplink. The FDD duplexing example may use frames that may consist of both a downlink portion (DCI and DL TRx) and an uplink portion (UL TRx), such as frame 510, which may include DCI 511, DL TRx 512, and UL TRx 513. Also shown in FIG. 5 is frame 520, which may include DCI 521, DL TRx 522, and UL TRx 523. The uplink portion may overlap two frames, such as uplink portion 514, which overlaps with frames 510 and 520.

[0104] The start of the uplink TTI is shown in Figure 5. offset 530, etc., offset (e.g., t offset ) The offset may be applied from the start of the downlink reference frame, which may overlap with the start of the uplink frame.

[0105] An FDD example may support D2D, V2X, and / or sidelink operations during the UL TRx portion of a frame by including respective downlink control, forward, and / or reverse transmissions during the UL TRx portion of such frame (e.g., dynamic allocation of one or more respective resources may be used).

[0106] Scheduling functionality may be supported at the Medium Access Control (MAC) layer. Two or more scheduling modes may be supported. A scheduling mode may be network-based scheduling, which may be used for tight scheduling with respect to resources and timing and transmission parameters of downlink and / or uplink transmissions. Another scheduling mode may be WTRU-based scheduling, which may provide flexibility with respect to timing and / or transmission parameters. For either or both such modes, the scheduling information may be valid for a single TTI or for multiple TTIs.

[0107] Network-based scheduling may be used, for example, to allow the network to manage available radio resources that may be assigned to various WTRUs. Such a scheduling scheme may be used to improve sharing of such resources. Dynamic scheduling may also or instead be supported.

[0108] WTRU-based scheduling may be used to help a WTRU opportunistically access uplink resources as needed with minimal latency, for example within a set of shared and / or dedicated uplink resources allocated by the network (dynamically or otherwise). Synchronous and asynchronous opportunistic transmissions are contemplated in this disclosure. Contention-based and contention-free transmissions are contemplated in this disclosure.

[0109] Support for opportunistic transmissions (scheduled or unscheduled) may be used to address ultra-low latency requirements that may be associated with some configurations and / or power saving requirements that may be associated with some configurations.

[0110] Association of data available for transmission and available resources for uplink transmission may be supported. Multiplexing of data with different QoS requirements within the same transport block may be supported, for example, where such multiplexing may not adversely affect services with stringent QoS requirements and / or may not result in unnecessary waste of system resources.

[0111] A transmission may be coded using one or more coding methods. Different coding methods may have different characteristics. For example, a coding method may produce a sequence of information units. Each information unit, sometimes referred to as a "block," may be standalone such that an error in the transmission of a first block does not impair the receiver's ability to successfully decode a second block. For example, if the first block has an error, the second block may be error-free and / or have sufficient redundancy such that the second block may be successfully decoded. The second block may be decoded by the receiver and the first block may not be decoded due to an error associated with the first block.

[0112] Coding methods may be used, such as Raptor / Fountain codes, where a transmission may consist of a sequence of N Raptor codes. One or more such codes may be mapped in time to one or more transmission "symbols." Such symbols may correspond to one or more sets of information bits (e.g., one or more octets). Such coding may be used to add forward error correction (FEC) to a transmission, for example, so that a transmission may use N+1 or N+2 Raptor codes (or symbols, assuming Raptor code symbol relationships) so that the transmission may be more resilient to the loss of one "symbol" due to interference or puncturing by another transmission that overlaps in time.

[0113] The WTRU may be configured to receive and / or detect one or more system signatures. A system signature may include a signal structure that may use a sequence. A signal including such a system signature may be similar to a synchronization signal (e.g., similar to an LTE Primary Synchronization Signal (PSS) or Secondary Synchronization Signal (SSS)). A system signature may be specific to (e.g., uniquely identify) a particular node and / or transmission / reception point (TRP) in a given area. Alternatively, or additionally, a system signature may be common to multiple nodes and / or TRPs in an area. Whether a signature is specific to a node and / or TRP may be unknown and / or irrelevant information to the WTRU. A network TRP supporting NR transmission and / or reception may be referred to as a gNB.

[0114] The WTRU may determine and / or detect a system signature sequence and may determine one or more parameters associated with the system. For example, the WTRU may derive an index from the system signature sequence and use this index to look up the associated parameters, e.g., by using a table such as an access table as described herein. If the WTRU determines that it may access and / or transmit using the applicable resources of the system, the WTRU may use a received power associated with the system signature for open loop power control, e.g., to set an initial transmit power. If the WTRU determines that it may access and / or transmit using the applicable resources of the system, the WTRU may use the timing of the received signature sequence, e.g., to set the timing of the transmission (e.g., a preamble on a PRACH resource).

[0115] A WTRU may be configured with a list having one or more entries. Such a list may be referred to as an access table. The access table may be indexed such that each entry may be associated with a system signature and / or a sequence associated with the system signature. The access table may provide initial access parameters for one or more areas. Each access table entry may provide one or more parameters that may be used to perform an initial access to the system. The parameters included in the access table may include a set of one or more random access parameters, which may include, for example, applicable physical layer resources, such as one or more physical random access channel (PRACH) resources, in time and / or frequency, an initial power level, one or more physical layer resources that may be used for receiving a response, etc., in any combination.

[0116] Parameters associated with an access table entry may also or instead include access restrictions, such as Public Land Mobile Network (PLMN) identity information and / or CSG information. Such parameters may also or instead include routing related information, such as one or more applicable routing areas. Each table entry may be associated with and / or indexed by a system signature. One entry may be common to multiple nodes and / or TRPs.

[0117] The WTRU may receive or obtain the access table by a transmission using dedicated resources, such as resources associated with an RRC configuration, and / or a transmission that may use broadcasted resources. If broadcasted resources may be used, the periodicity of the transmission of the access table may be relatively long (e.g., up to 10240 ms) such that it may be longer than the periodicity of the transmission of the signature (e.g., in the range of 100 ms).

[0118] Reducing transmissions, and therefore bandwidth usage, may be desirable. Reducing signals in the system may reduce unnecessary interference for neighboring transmission points (TRPs), reduce reference signal overhead, and / or reduce power consumption at the transmission points.

[0119] Reducing reference signal overhead may be beneficial for mobile broadband communications, for example, in environments where support for more than one method of transmission may be provided (e.g., massive MIMO, CoMP). Reducing reference signal overhead (e.g., pilot contamination) and / or reducing inter-TRP interference may increase coverage of higher order modulation transmissions and may be beneficial to WTRUs operating in such environments. Reducing inter-TRP interference may be beneficial for ultra-reliable communications.

[0120] The WTRU may perform measurements on one or more reference signals and may use such measurements for one or more of a variety of purposes, such as to measure received power, to measure channel quality, to enable derivation of CSI, to enable channel estimation for demodulation, etc. The WTRU may need to know when to expect transmission of a reference signal. Various methods and systems are described that may be used to indicate the presence of one or more reference signals to the WTRU.

[0121] The reduction in transmission of signals may be achieved by reducing the periodicity of some such signals. In some operating modes (e.g., ultra-reliable communications), it may be undesirable to introduce a lag between measured CSI feedback and actual transmission, as experienced with the reduction in periodicity of some signals.

[0122] To restrict transmission of one or more reference signals, the WTRU may perform multiple actions for one or more (e.g., one) reference signal types. The WTRU may be informed of the purpose of the reference signal.

[0123] It should be noted that the acronym "NR" for new radio may be used herein to identify a new air interface that may differ from the LTE interface. NR may also be used to indicate an interface contemplated as being used in future systems. The systems and methods described herein may be applicable to either or both of receiving one or more reference measurement resources (RMRs) and transmitting one or more RMRs.

[0124] A WTRU may be configured with one or more RMRs. For the downlink, the one or more RMRs may be used to perform measurements for at least one signal transmission (e.g., a transmitted signal RMR, if present, may be used to perform measurements for at least one signal) and / or may be used to perform measurements for resources where at least one signal may not be expected (e.g., a blanked RMR, if present, may be used to perform measurements for one or more resources where at least one signal may not be expected).

[0125] For the uplink, one or more RMRs may be used to effect transmission of at least one signal (e.g., a transmit signal RMR, if present, may be used to effect transmission of at least one signal). Alternatively, or in addition, no transmission may be effected (e.g., based on a blanked RMR, if present). It should be noted that examples described herein referring to reception of an RMR (e.g., DL RMR or SL RMR) by the WTRU may also be applicable to transmission of an RMR (e.g., UL RMR or SL RMR) by the WTRU, for example.

[0126] The WTRU may detect the presence of one or more resources on which the WTRU may perform one or more measurements. Such a resource may be an RMR. The RMR may be a non-zero power reference signal on which at least one TRP may transmit a signal. The RMR may also or instead be a zero power reference signal on which at least one TRP may not transmit a signal (e.g., one or more TRPs may not transmit a signal on unused resources). The non-zero power reference signal RMR may be referred to as a "transmitted signal RMR." The zero power reference signal RMR may be referred to as a "blanked RMR."

[0127] As used herein, "transmission of an RMR" may refer to either or both of the transmitted signal RMR and the blanked RMR. Furthermore, as used herein, "transmission of an RMR" should be understood as equivalent to "presence of an RMR" (e.g., in a resource grid, which may represent a set of applicable physical layer resources).

[0128] The transmitted RMR may be the RMR that may be transmitted by the WTRU in the UL, while the blanked RMR may be a set of resources on which the WTRU may not transmit anything. For example, the blanked RMR may indicate to the WTRU a pattern of resources on which the WTRU may rate match and / or puncture UL transmissions.

[0129] It should be noted that the examples described herein may be described in the context of reference measurement resources that may be transmitted by one or more TRPs, and it is contemplated that the disclosed examples may also be applicable to a WTRU that may be transmitting, for example, one or more RMRs when operating in a device-to-device communication mode.

[0130] The RMR may be characterized by one or more parameters. One or more RMRs may be configured for a WTRU. Such a WTRU may expect that at least one TRP may transmit a signal. Such a WTRU may use certain parameters that may enable the WTRU to use advanced detection to make the required measurements. For example, the RMR may be defined by (and / or configured with) at least one of a variety of parameters.

[0131] Parameters associated with the RMR may include, but are not limited to, resource element mapping. Resource element mapping may map the RMR to a set of resource elements in one or more symbols and / or to one or more subcarriers. In an example, the RMR may be a concatenation of multiple resource elements.

[0132] The parameters associated with the RMR may include, but are not limited to, a sequence that may be predetermined in some examples. For example, a signal transmitted by at least one TRP on the RMR may be a predetermined sequence. The sequence may be generated, for example, using a pseudo-random sequence. The sequence may be generated using one or more other parameters of the RMR.

[0133] The parameters associated with the RMR may include, but are not limited to, a unique word, such as Unique Word OFDM (UW-OFDM), that may be used to transmit the RMR. A guard period may be used in one or more frame structures (e.g., in a standalone subframe where the DL and UL portions may be separated by a guard period). Such a guard period may be used to transmit the RMR.

[0134] Parameters associated with the RMR may include, but are not limited to, a signal structure. The RMR may have a signal structure that is different from that of the one or more parallel transmissions. For example, the RMR may use a first subcarrier spacing, and the one or more parallel non-RMR transmissions may use a second subcarrier spacing. The RMR may also, or instead, assume a first TTI duration or subframe duration, and the one or more parallel non-RMR transmissions may use a second TTI duration or subframe duration.

[0135] The parameters associated with the RMR may include, but are not limited to, a transmission power. The transmission power of the RMR may be fixed or may be variable across different implementations of the same RMR. The RMR transmission power may be associated with a parallel transmission of another channel.

[0136] Parameters associated with an RMR may include, but are not limited to, an analog beam. Multiple RMRs may be multiplexed in the same or overlapping resources using different beams.

[0137] Parameters associated with the RMR may include, but are not limited to, precoding. The precoding used to transmit the RMR on multiple antenna ports may be fixed or variable. The RMR precoding may be tied to the parallel transmission of another channel.

[0138] Parameters associated with the RMR may include, but are not limited to, a set of antenna ports that may be used for transmissions from one or more TRPs.

[0139] Parameters associated with an RMR may include, but are not limited to, a cover code. Multiple RMRs may be multiplexed in the same or overlapping resources using orthogonal cover codes.

[0140] Parameters associated with the RMR may include, but are not limited to, timing aspects. The RMR may be associated with a periodicity with respect to time, such as with respect to symbols within a subframe, with respect to a subframe (e.g., one or more symbols), and / or with respect to a radio frame (e.g., multiple subframes).

[0141] It should be noted that any of the parameters associated with the RMR described herein may be associated with one or more of a downlink transmission, an uplink transmission, and / or a sidelink transmission.

[0142] An RMR configured for a WTRU that may expect one or more TRPs to not be transmitting may use parameters that are the same and / or similar to those described herein for an RMR configured for a WTRU that may expect one or more TRPs to transmit a signal.

[0143] One or more blanked RMRs may be assumed by the WTRU to consist of interference and noise. In such an example, the WTRU may perform energy detection.

[0144] One or more blanked RMRs may be used by the WTRU to measure a particular type of interference. A WTRU may be configured with blanked RMRs by an NR network node to allow the WTRU to measure interference from other RATs (e.g., LTE, Wi-Fi, etc.). Such a WTRU may be configured with parameters that may be associated with inter-RAT interference. Targeted interference measurements may be kept separate from one or more measurements performed by the WTRU for energy detection.

[0145] One or more blanked RMRs may be used by the WTRU to measure one or more signals transmitted by one or more other RATs. The WTRU may be configured with at least one blanked RMR that may coincide with a transmission of LTE CSI-RS (or other type of LTE RS) from an LTE cell that may be co-located with a TRP (e.g., an NR TRP) with which the WTRU communicates. The WTRU may also, or instead, be configured with a blanked RMR that may coincide with a transmission of LTE CSI-RS from an LTE cell that is not co-located with a TRP with which the WTRU communicates. The WTRU may be configured with at least one blanked RMR that may enable inter-RAT mobility measurements.

[0146] The WTRU may be configured to perform one or more measurements. Such measurements may be performed on one or more RMRs. Each such measurement may be associated with an objective that may correspond to a particular procedure.

[0147] The measurements may be associated with one or more WTRU procedures, including but not limited to procedures for cell, signature, TRP, TRP group (TRPG), and sidelink WTRU selection. The measurements may also or instead be associated with one or more other WTRU procedures, including but not limited to mobility related measurements (e.g., intra or inter cell / signature / TRPG or RAT), Radio Link Monitoring (RLM) related logic, Radio Link Failure (RLF) related logic, demodulation processes, etc.

[0148] The purpose for the measurement may correspond to the SOM. For example, the measurement may be associated with the operation of a particular service, transport channel (TrCH), and / or physical channel (or type thereof).

[0149] The measurements may be used, for example, locally by the WTRU and / or to provide feedback that may be reported by the WTRU to at least one TRP. The WTRU may be dynamically or semi-statically configured to perform specific measurements for one or more RMRs. The WTRU may autonomously determine the measurements to be taken for one or more RMRs.

[0150] Any one or more measurements may be performed for any one or more of several purposes. The measurements may be used to identify a TRP. If one or more RMRs may be used by the WTRU to determine the presence of one or more TRPs, then measurements of such one or more RMRs may be used to identify one or more TRPs. The RMR may indicate the TRP identifier implicitly or explicitly (e.g., via a parameter). A TRP as used herein may refer to a node and / or a transmission configuration. An example transmission configuration may include a particular beam used by the TRP.

[0151] The measurements may be used to identify another WTRU. The RMR may be used by the first WTRU to determine the presence of the second WTRU or a set of other WTRUs. Alternatively, or in addition, the RMR may be used by the first WTRU to identify the second WTRU or a set of other WTRUs. The second WTRU may be configured to transmit during the RMR configured for the first WTRU. The second WTRU may transmit a signal that may explicitly or implicitly provide identification information to the first WTRU.

[0152] The measurements may be used for synchronization. A WTRU may use the RMR to synchronize with one or more TRPs and / or with one or more other WTRUs. The RMR may be used for coarse and / or fine time synchronization. Additionally or alternatively, the RMR may be used for coarse and / or fine frequency synchronization.

[0153] The measurements may be used to perform one or more mobility measurements. Mobility measurements, sometimes referred to as higher layer measurements, may include one or more of the following: RMR received power (e.g., power measured over one or more RMRs), RMR received quality (e.g., power measured over one or more RMRs divided by a signal strength indicator), and an RMR signal strength indication (e.g., power measured over one or more symbols).

[0154] The measurements may be used to determine a path loss estimate (or similar measurements) for one or more TRPs and / or another WTRU or WTRUs. Such measurements may be used in combination with one or more other parameters. The RMR may have a fixed transmit power or a configurable transmit power, either of which may be known or indicated at the WTRU. The WTRU may use the received power of the RMR in combination with the transmit power of the RMR to determine the path loss.

[0155] The measurements may be used to perform CSI measurements. The WTRU may use the RMR to obtain CSI measurements, which may include, but are not limited to, one or more of rank, preferred precoder matrix, channel quality, selected subband, interference, dominant interferer identity, preferred beam, preferred channel, signal-to-interference-plus-noise ratio (SINR), channel outage, WTRU speed, coherence time, and coherence bandwidth.

[0156] The measurements may be used to perform Radio Link Monitoring (RLM). The WTRU may use the RMR to perform RLM. The WTRU may determine whether the received signal strength may be above a threshold. The threshold may be associated with a required control channel block error rate (BLER) performance. Such a threshold may be configurable. The threshold may depend on the transmission and / or reception parameters of the WTRU. For example, different traffic types (e.g., eMBB, ultra-reliable and low latency communications ("URLLC"), mMTC) may have different associated thresholds.

[0157] The measurements may be used to perform demodulation. The WTRU may use the RMR to perform channel estimation, which may be used in demodulation.

[0158] The measurements may be used to perform quasi-co-location (QCL). The WTRU may use the RMR to obtain fine frequency and / or timing estimates. The QCL measurements may include one or more of Doppler shift, Doppler spread, average delay, and delay spread. The QCL information obtained on a first RMR may be used with a second or other RMR.

[0159] The measurements may be used to perform a clear channel assessment. The WTRU may use the RMR to perform one or more measurements that may be used to determine a clear channel assessment for an unlicensed channel, for example.

[0160] The measurements may be used to perform signal structure identification. The WTRU may use the RMR to determine a preferred signal structure. Alternatively, or in addition, the WTRU may use the RMR to blindly determine the signal structure that may be in use. The WTRU may perform measurements assuming different signal structures and may use a correlation receiver to determine the signal structure in use.

[0161] The measurements may be used to perform channel occupancy determination. The WTRU may use the RMR to determine the number of devices that may be using the channel. For example, the WTRU may use the RMR to detect signaling messages from other devices (e.g., other WTRUs) to determine channel occupancy. Alternatively, or in addition, the WTRU may use the RMR to measure utilization of a set of resources (e.g., a portion of resources used by other devices to transmit data). Utilization of the set of resources may be determined based on energy detection and / or control channel detection. The WTRU may be configured with different measurement thresholds that may be associated with different channel occupancy values. Channel occupancy may also, or instead, be determined depending on how often measurements are above or below the measurement threshold in a set of measurement occasions.

[0162] The measurements may be used to perform a determination of a type of channel utilization based on the measurement of the RMR, the presence of the RMR, and / or parameters of the RMR. The WTRU may have limited access to the channel (e.g., a shared access channel) depending on the current channel utilization type. The channel utilization type may be SOM, a transmission type (e.g., URLLC or mMTC), or a shared spectrum tier of the user (e.g., incumbent, Priority Access License (PAL) tier, General Authorized Access (GAA) tier). The WTRU may be configured with a blanked RMR. Such a WTRU may determine a type of interference that may be present within one or more resources of such a blanked RMR, for example, to determine a type of channel utilization. In an example, such a WTRU may also perform one or more other decisions based on such a determination of a type of interference.

[0163] The measurements may be used to perform velocity and / or Doppler estimation. The WTRU may use one or more RMRs to estimate the velocity of the WTRU. The WTRU may also, or instead, use one or more RMRs to feed back measurements to the network for velocity estimation purposes. Such measurements may be based on the relative timing of reception of one or more associated signals.

[0164] The measurements may be used to determine positioning. The WTRU may use one or more RMRs to determine the WTRU's position. The WTRU may also, or instead, use one or more RMRs to feed back measurements to the network for positioning purposes. One or more associated signals may be designed to enable positioning.

[0165] Any measurement purpose and measurement type, and any combination thereof, may be implemented in accordance with the present disclosure. Any measurement purpose and measurement type, and any combination thereof, may be an embodiment of the present disclosure. All such measurement purposes and measurement types, and any combination thereof, are contemplated as being within the scope of the present disclosure.

[0166] The WTRU may "blindly" determine one or more RMR configurations. Such a determination may be based on transmission and / or transmission parameters of the signal and / or RMR, either or both of which may not be associated with the RMR for which the WTRU may be determining a configuration. The WTRU may determine one or more RMR configurations based on the signal structure, the SOM, and / or the frame structure. The waveform in use may indicate one or more RMR configurations.

[0167] The WTRU may determine one or more RMR configurations in response to a downlink signal, which may not be associated with one or more RMRs for which the WTRU may be attempting to determine a configuration. The WTRU may determine one or more RMR configurations in response to one or more access parameters. For example, the WTRU may determine the RMR configuration using a TRP identity, a TRPG identity, a system signature, a cell identity, and / or physical resources that may be applicable, for example, to a transmission of a preamble. The WTRU may determine one or more RMR configuration aspects in response to a preamble transmission (e.g., a selected preamble, PRACH resources, applicable subframes) and / or in response to a Radio Network Temporary Identifier (RNTI) for decoding the response, such as, for example, a Random Access RNTI (RA-RNTI).

[0168] A WTRU may be configured for transmission and / or reception of one or more RMRs. Such configurations may be dynamic, semi-static, or static. The RMR configurations may be indicated via the physical layer and / or one or more higher layers. If a WTRU may be semi-statically configured with one or more RMR configurations, one or more of such configurations may be tied to a respective RMR ID. The semi-static configuration may be implemented via system information and / or higher layer signaling (e.g., RRC). The RMRs may be dynamically activated and / or deactivated using an indication of the RMR ID in some examples. The indication of the RMR ID may be communicated using PHY layer signaling (e.g., DCI, or a control channel from another device).

[0169] "RMR," "RMR configuration," "RMR instantiation," "RMR activation," and "RMR deactivation" may be used interchangeably herein. Any aspect described herein as associated with any one or more of these terms is contemplated as being applicable to any other of these terms, and to any respective devices, systems, and methods.

[0170] The RMR, RMR configuration, and / or RMR instantiation may include an associated identifier, such as an RMR ID, that may identify the respective RMR, RMR configuration, and / or RMR instantiation.

[0171] The RMR, RMR configuration, and / or RMR instantiation may include an RMR resource mapping. Such resource mapping may include one or more of subcarriers and / or symbol locations. Such resource mapping may also, or instead, include one or more of subframes that may be within a frame. Such resource mapping may also, or instead, include one or more of subframe offsets, TTI offsets, each or both of which may be associated with a subframe periodicity or TTI periodicity. Such resource mapping may also, or instead, include one or more indications of antenna ports that may be associated with one or more beams for which the RMR may be received by the WTRU, for example.

[0172] The RMR, RMR configuration, and / or RMR instantiation may include an RMR presence duration and / or an indication thereof. Such a configuration may be associated with a single instance of RMR (e.g., on one or more symbols that may be in one or more subframes). Such a configuration may also, or instead, be associated with multiple instances of RMR. A WTRU may be configured with an RMR and may assume the presence of this RMR in one or more associated symbols and / or subframes. In some examples, such a WTRU may be configured with periodicity and may assume the presence of RMR until the WTRU may be instructed by an associated TRP or other device to cease assuming the presence of RMR. Alternatively, or instead, an RMR configuration may include a period during which the configuration is valid. Such a period may be measured in symbols, subframes, frames, time units, or any other unit or measure.

[0173] The RMR, RMR configuration, and / or RMR instantiation may include an RMR frequency. An RMR configuration may be associated with a subband, a set of subcarriers, and / or a frequency block. A WTRU may be configured with an RMR applicable to a set of subbands and subsequently configured to remove (or deactivate) the RMR in a particular subband contained within that set of subbands.

[0174] The RMR, RMR configuration, and / or RMR instantiation may include an RMR measurement purpose and / or associated procedure, or an indication thereof. Such purpose and / or procedure may indicate one or more purposes to the WTRU of the RMR. For example, the RMR may be configured to be transmitted along with one or more parallel data transmissions. Such an RMR configuration may include, for example, an association with a demodulation purpose. For the same RMR, the RMR configuration may include, for example, an association with a CSI feedback purpose. In such an example, the WTRU may determine an association between the measurement configuration and one or more procedures (e.g., demodulation, mobility, radio link monitoring, etc.).

[0175] The RMR, RMR configuration, and / or RMR instantiation may include an RMR measurement configuration. The RMR measurement configuration may indicate to the WTRU a relationship between multiple RMRs and / or multiple resources of the RMR (e.g., multiple resources of the RMR may be defined as each individual resource used within one instantiation of the RMR, for example, and / or multiple resources of the RMR may be defined to be transmitted multiple times within a time period). The WTRU may be configured with multiple RMRs for which it may take the same measurement type. In such an example, the RMR measurement configuration may indicate to the WTRU that multiple (e.g., all) RMRs may be assumed to represent the same instantaneous channel realization. Such a WTRU may perform short-term channel measurements. Alternatively, or instead, the RMR measurement configuration may indicate to the WTRU that a configured set of RMRs (or a set of resources including the RMRs) may be assumed to span multiple channel realizations. In such an example, the WTRU may perform long-term channel statistics type measurements.

[0176] The RMR, RMR configuration, and / or RMR instantiation may include an RMR measurement configuration that may be associated with an RMR process. Such a process may be associated with a set of RMR instances. The RMR configuration (e.g., a dynamically signaled RMR configuration) may indicate, for example, via an information element (IE), an RMR process ID. This IE may indicate to the WTRU whether measurements taken for the RMR may be combined (e.g., averaged) with measurements taken for a previous RMR instance of the identified RMR process.

[0177] The RMR, RMR configuration, and / or RMR instantiation may include an indication of RMR dependency. A first RMR or RMR process may be configured with a dependency on or association with a second RMR or RMR process. A WTRU may modify its use of such a first RMR or RMR process based on the WTRU's use of the second RMR or RMR process. For example, a WTRU may be configured with a first RMR or RMR process that may have a channel estimation purpose for demodulation. This first RMR or RMR process alone may not enable the WTRU to obtain a sufficient channel estimate. This WTRU may be configured with a second RMR or RMR process with which it may make one or more measurements that may improve the channel estimate performed using the first RMR or RMR process. The WTRU may obtain QCL information (e.g., Doppler shift, Doppler spread, average delay, delay spread) for the second RMR or RMR process and use such QCL information associated with the second RMR when performing channel estimation for the first RMR or RMR process. Alternatively, or instead, the first RMR or RMR process may be configured as a reference RMR or RMR process that may be used with the second RMR or RMR process that may be configured to have a dependency on the reference (first) RMR or RMR process.

[0178] The RMR, RMR configuration, and / or RMR instantiation may include an indication of one or more associated TRPs and / or WTRUs. This indication may indicate a source of a signal that may be measured. If the source of a signal that may be measured may be another WTRU, the TRP / WTRU value may correspond, for example, to an L2 WTRU identity that may be used for direct communication. If the source of a signal that may be measured may be an eNodeB, the TRP / WTRU value may correspond, for example, to a cell ID, a TRP identity, a TRPG identity, and / or their access parameters (e.g., from an access table and / or from system information).

[0179] Any one or more of the disclosed parameters of the RMR may be determined autonomously by the WTRU. The WTRU may autonomously determine that a set of RMRs or a set of resources including the RMRs may cover an instantaneous channel realization. Alternatively, or in addition, the WTRU may autonomously determine that a set of RMRs or a set of resources including the RMRs may cover multiple channel realizations. The WTRU may make such a determination based on, for example, the WTRU's velocity, delay spread estimate, coherence time, and / or coherence bandwidth.

[0180] The WTRU, upon feeding back one or more measurements, may indicate to the network one or more of the WTRU's assumptions associated with the RMR configuration parameters (e.g., such one or more measurements may be associated with one or more respective values ​​that may depend on one or more of the WTRU's assumptions). A decision of whether to provide such assumptions and / or measurements to the network may be made depending on another measurement result, such as a result associated with the same or other set of RMRs. For example, the WTRU may measure a coherence time on a first set of RMRs and use that value to autonomously determine whether a second set of RMRs may span a single or multiple channel implementation.

[0181] RMR configuration, activation, and / or deactivation may be indicated to the WTRU in a dynamic manner. For example, RMR configuration, activation, and / or deactivation may be TRP-specific, group-specific (e.g., for a subgroup of WTRUs served by a TRP and / or device), and / or WTRU-specific. Such RMR configuration, activation, and / or deactivation may be indicated in a broadcast message.

[0182] The access table may be used to provide at least a portion of the system information associated with the TRP. The access table may include one or more elements that may be used to configure one or more RMRs.

[0183] The RMR may be configured in or by a WTRU-specific transmission of system information.

[0184] The RMR indication may be provided using a control channel and / or parts thereof. For example, downlink control information (DCI) may be used to provide the RMR indication. An RMR configuration DCI may be transmitted to a WTRU or to a group of WTRUs. Such a DCI may include some or all of the RMR configuration.

[0185] The RMR may also or instead be used for cell-specific purposes. The WTRU may be configured with an RNTI (e.g., RMR-RNTI) that may be used for receiving downlink control information associated with the RMR for one or more purposes (e.g., scheduling, activation, and / or deactivation). A common RNTI may be used and configured for the WTRU. The purpose associated with the RMR may be one or more of performing mobility-related measurements, performing positioning, performing radio link monitoring, and performing cell collection.

[0186] The WTRU may decode a DCI associated with an RMR configuration in the common search space. Such a DCI may indicate one or more characteristics of the RMR and / or indicate a change in the activation state of the RMR. The DCI indication may be used to provide dynamic control of one or more transmissions for a common reference signal associated with one or more WTRUs and / or for any other one or more purposes.

[0187] An RMR indication using a DCI may also provide information associated with one or more other transmissions. For example, a DCI used for scheduling one or more DL transmissions may also include elements that may be used to configure, activate, and / or deactivate an RMR.

[0188] The RMR indication may be used for one or more cell-specific purposes. RMR-related control information may be included in the DCI, which may schedule and / or indicate another transmission (e.g., one or more Multimedia Broadcast Multicast Service (MBMS) transmissions), a separate Positioning Reference Signal (PRS), and / or a system information broadcast.

[0189] The RMR indication may be implemented using a split DCI approach. For example, the WTRU may expect multi-step physical layer signaling (e.g., DCI). As used herein, "DCI" may refer to any physical layer signaling method.

[0190] The WTRU may expect a two-step DCI approach. FIG. 6 shows a diagram 600 illustrating an example DCI configuration and activation / deactivation process. In block 651, a first DCI 610 (e.g., a long-term, wideband, and / or less frequent DCI, where the less frequent DCI may be applicable to multiple WTRUs) may be used to transmit a configuration of at least one RMR, such as RMR 601 and 602. The configuration of the first DCI 610 may include one, multiple (e.g., common to multiple WTRUs), or all RMR parameters (e.g., dedicated to a single WTRU). The first DCI 610 may also or instead indicate one or more RSs, such as RS 631 and RS 632, that may be used as resources, e.g., for one or more measurements.

[0191] In block 652, a second DCI 620 (e.g., a short-term, sub-band, and / or more frequently transmitted DCI that may be applicable to a single WTRU or transmission) may be used to provide parameters for the same RMR for which parameters may also be provided in the first DCI 610, such as the RMR 602. The second DCI 620 may indicate parameters associated with an RMR, such as the RMR 602, that may change more frequently than the parameters indicated in the first DCI 610 (e.g., that may also be associated with the RMR 602).

[0192] For example, a WTRU may receive parameters for an RMR and / or a reference to a configuration associated with an RMR (e.g., RMR 602) in a first DCI 610 in block 651. Such a WTRU may determine whether it should use such an RMR to perform further actions. In an example, reception of a second DCI 620 in block 652 (which may be transmitted, for example, in a control region in or across a subband or a channel controlling the subband) may trigger such a WTRU to anticipate, in some examples, an actual transmission of an RMR on the subband used by the second DCI 620.

[0193] The WTRU may receive a DCI, such as the second DCI 620, at block 652, which may indicate that one or more RMRs, such as the RMR 602, may be turned on (e.g., activated and / or applicable for an associated transmission) or turned off (deactivated). For example, the second DCI 620 may be used at block 652 to, for example, dynamically turn on and / or turn off the RMR 602 over a particular time scale. Such a time scale may correspond to a symbol (or multiple thereof), a subframe and / or TTI (or multiple thereof), and / or a subband (or multiple thereof).

[0194] A DCI, such as the second DCI 620, may be used to dynamically turn on and / or off an RMR, such as one or both of RMR 601 and RMR 602, based on a configuration that may include parameters such as, but not limited to, time, frequency, code, and / or space. Such parameters may be used to determine how and / or when the RMR should be dynamically turned on and / or off. Alternatively, or additionally, a DCI, such as the second DCI 620, may indicate the purpose of the RMR for different subframes (or TTIs) and / or subbands.

[0195] The second DCI 620 may be used to change or adjust parameters of an RMR, such as the RMR 601, within a relatively short time frame. In an example, the second DCI 620 may activate the RMR 601 with one or more parameters, such as a fixed duration (e.g., lifespan), in block 653. In such an example, the second DCI 620 may activate the RMR 601 in block 654 with one or more parameters that may differ from the parameters used in block 653.

[0196] The second DCI 620 may be used to deactivate an RMR, such as RMR 601. In an example, at block 655, the second DCI 620 may deactivate RMR 601.

[0197] In block 656 , the first DCI 610 may be used to transmit a configuration of at least one other RMR, such as RMRs 603 and 604 .

[0198] A second DCI, such as the second DCI 620, may be applicable in one or more combinations with a first DCI, such as the first DCI 610. A combination of an appropriate first DCI with an appropriate second DCI may be explicitly indicated (e.g., in the first and / or second DCIs, such as the first DCI 610 and the second DCI 620). A first DCI, such as the first DCI 610, may include scheduling information and / or presence information (e.g., a presence indication) for a second DCI, such as the second DCI 620.

[0199] A relationship between a first DCI and a second DCI may be implicitly determined. A first DCI, such as a first DCI 610, may be associated with a set of one or more subbands, symbols, and / or subframes. A second DCI, such as a second DCI 620, that may be received by a WTRU within a set of subframes and / or subbands associated with such a first DCI, may be assumed by such WTRU to be associated with such first DCI.

[0200] 7 shows a diagram 700 illustrating an example DCI process. At block 710, a WTRU may transmit a request for one or more RSs, e.g., on the UL, where such a WTRU may determine that it may experience performance degradation. In an example, such a request may not be transmitted.

[0201] In block 720, DCI 721 may indicate RS 731 and RS 741 on the DL. DCI 721 may indicate that RS 731 and RS 741 may be resources that may be used for CSI measurements. RS 731 may be provided in block 730 and RS 741 may be provided in block 740.

[0202] At block 750, a subsequent DCI 751 may request a CSI report 761 in the DL. In an example, RS 731 may be associated with the signal and RS 741 may be associated with interference. Alternatively, RS 741 may be associated with the signal and RS 731 may be associated with interference. At block 760, the CSI report 761 may be transmitted in the UL.

[0203] A WTRU may miss an RMR activation. Such a WTRU may not perform one or more configured measurements. Measurements and / or channel estimation procedures (e.g., data demodulation, measurement feedback) associated with such an RMR may be difficult to perform. In some examples, such measurement procedures may not be able to be performed. In such examples, the WTRU may, for example, report to one or more associated serving TRPs that it has failed to perform the associated procedures. Such a WTRU may indicate the cause of the failure as a lack of an RMR.

[0204] A WTRU may miss an RMR deactivation. Such a WTRU may continue to attempt to perform one or more measurements and / or other tasks associated with one or more objectives associated with the RMR for which deactivation was missed. Such a WTRU may attempt to perform such one or more measurements and / or other tasks using one or more resources for which the WTRU erroneously expects an RMR to be present. In an example, the WTRU may be able to determine an abnormal change in one or more measurements that may have been taken for a first RMR instance, for example, based on a comparison with a second RMR instance that the WTRU may assume had some dependency on the first RMR instance. Such a WTRU may report to the TRP that it has experienced an unexpected change. Based on such a report, the TRP may determine that the WTRU did not successfully receive the RMR deactivation.

[0205] The RMR process may include multiple RMR instances. The WTRU may expect similarity of measurements taken based on different RMR instances of the first RMR process. If the measurements change, for example, by a threshold amount (which may be configurable), the WTRU may determine that an unexpected change may have occurred and may provide an indication of such unexpected change to the TRP.

[0206] The WTRU may use the RMR process for channel estimation and / or may determine that the signal strength has changed by more than a threshold amount, for example, over two consecutive RMR values. Such a WTRU may indicate such a determination to the TRP.

[0207] The WTRU may acknowledge receipt of the RMR deactivation and / or RMR activation. The WTRU may acknowledge receipt of the RMR deactivation and / or RMR activation for one or more long-term RMR processes. The WTRU may indicate one or more RMR instances for which feedback measurements may be applicable.

[0208] The presence of an RMR may be indicated to the WTRU in an implicit manner. For example, the WTRU may determine the presence of an RMR via implicit means. A DCI that may grant one or more DL resources may implicitly configure, activate (e.g., applicable to one or more transmissions), and / or indicate (e.g., applicable to an associated transmission) the presence of an RMR, for example, for use in demodulating one or more DL transmissions.

[0209] The presence of an RMR may be determined upon requesting measurement feedback from the WTRU.

[0210] Reception of the second RMR may be dependent on reception of the first RMR. For example, the WTRU may be configured and / or activated with the first RMR that may be included or associated with being transmitted, and such configuration may implicitly indicate to the WTRU the presence of the first RMR.

[0211] Reception of one or more reference signals, or one or more measurements thereof, for a second RMR may have a dependency on reception of a first RMR. For example, a WTRU may be configured with and / or activated to anticipate the presence of a first RMR that may indicate a similar configuration and / or activation state (e.g., activation or presence) of a second RMR. Such a WTRU may receive and / or perform measurements on such a first RMR to determine outcomes that may be used to trigger one or more measurements on such second RMR, for example.

[0212] The RMR indication may be implicitly determined, for example, based on a configured change of one or more transmission parameters. The WTRU may receive an indication and / or command to reconfigure the SOM, frame structure, and / or signal structure. The associated RMR may also be reconfigured. Such RMR reconfiguration may be predetermined.

[0213] The RMR reconfiguration may be based on a function of the new signal structure. Alternatively, or additionally, an RMR configuration may be assumed to be associated with a signal structure. A change in such a signal structure may indicate deactivation of the associated RMR. A WTRU may store an RMR configuration for one or more transmission parameters (such as a signal structure). For example, upon reconfiguration to use a previously used set of transmission parameters, such a WTRU may reuse one or more previously configured RMRs and / or one or more RMR configurations associated with such set of transmission parameters.

[0214] An RMR configuration may be associated with one or more TRPs, TRPGs, system signatures, cell identities, etc., or any combination thereof. A reconfiguration of the WTRU that may modify one or more of such TRPs, TRPGs, system signatures, cell identities, etc., or any combination thereof (e.g., a mobility event) may reconfigure the associated RMR configuration. For example, the WTRU may determine applicable RMR configurations based on a list of pre-configurations and / or RMR configurations, each of which may be associated with one or more TRPs, TRPGs, system signatures, cell identities, etc., or any combination thereof.

[0215] An exemplary frame structure may be used for one or more DL and / or UL transmissions that may be transmitted to and / or received from a WTRU. Such an exemplary frame structure may include a preamble that may be transmitted by a TRP and received by a WTRU and / or another TRP. This preamble may be transmitted and / or received prior to or at the beginning of the frame structure, in some examples, immediately prior to the beginning of the frame structure. Such a preamble may include an RMR that may be semi-statically configured. Such an RMR may enable demodulation of information that may be transmitted within the preamble.

[0216] The preamble may include an RMR (e.g., an RMR that may be transmitted in parallel to the preamble) that may be used for one or more control regions that may be in at least one of a set of frames and / or subframes for which such a preamble may be transmitted. Alternatively, or instead, the preamble may include an instruction to the WTRU that indicates and / or commands such WTRU to determine the presence and / or one or more parameters of an RMR that may be used for one or more control regions in at least one of a set of frames and / or subframes for which such a preamble may be transmitted. The transmission of the preamble may include the transmission of a DCI, such as, without limitation, a first DCI and / or a second DCI, as described herein.

[0217] A preamble may include configurations for one or more RMRs. An RMR configuration associated with and / or included with such a preamble may be valid for a frame or set of frames for which the preamble may be transmitted. An RMR configuration associated with and / or included with such a preamble may be valid for a subset of frames (or subframes) for which the preamble was transmitted. A preamble transmission may include a transmission of a DCI, such as, but not limited to, a first DCI and / or a second DCI, as described herein.

[0218] The WTRU may determine an RMR that may be applicable for one or more downlink and / or uplink transmissions for one or more TRPs, TRPGs, system signatures, cell identities, etc., or any combination thereof. Alternatively, or in addition, the WTRU may determine an RMR that may be applicable for one or more downlink and / or uplink transmissions that may include a random access response (RAR), which may be a function of the transmission of a random access (RA) preamble. Alternatively, or in addition, the WTRU may determine an RMR that may be applicable for a transmission that may include an RAR as a function of one or more TRPs, TRPG identities, system signatures, cell identities, etc., or any combination thereof.

[0219] The RMR may be applicable until the WTRU can be reconfigured with an RMR (e.g., an alternative RMR parameter) using dedicated signaling. Such an RMR may be applicable for transmissions associated with one or more procedures, e.g., for a random access procedure, for mobility-related reconfiguration, during a mobility-related procedure, and / or until the WTRU can receive dedicated signaling for an applicable Uu association. For example, the WTRU may determine the applicable RMR depending on one or more resources that may be used in time and / or frequency for the transmission of the RA preamble and / or depending on the RMR used for the transmission of the RA preamble. Such a determination may be performed depending on an RA-RNTI that may be applicable for the reception of the associated RAR. In an example, such a determination may be performed in combination with the applicable identity.

[0220] A WTRU may be configured to determine an RMR (e.g., implicitly determine an RMR) based on one or more resources that may be used for data transmission and / or reception. A first WTRU may establish a connection or possibly begin communication with another (second) WTRU. The first and second WTRUs may determine a set of one or more resources that may be used to communicate with each other. One of such WTRUs, which may be a transmitting WTRU, may select a set of resources for one or more transmissions for a given time period (e.g., a scheduling period). The associated RMR may be valid for the duration of the given time period (e.g., a scheduling period). Alternatively, or additionally, the RMR may be defined as part of one or more resource definitions.

[0221] The WTRU may determine that it may use transmission of one or more RMRs and / or reconfiguration of one or more existing RMRs for various functions. The WTRU may support an on-demand PRS request mechanism, e.g., for positioning purposes. Such a request may include and / or indicate one or more request parameters, such as one or more of an applicable procedure, a desired accuracy, a speed estimate, etc. The WTRU may support an on-demand RMR request mechanism to implement WTRU autonomous mobility.

[0222] A WTRU may request transmission of an RMR, for example, by transmitting an RMR request in a UL transmission. A WTRU may have a periodic UL resource during which it may request an RMR. Such a WTRU may transmit a signal when it wishes to transmit one or more RMRs and may remain silent when it does not wish to transmit one or more RMRs. The WTRU may transmit a codepoint that may indicate whether the WTRU wishes an RMR.

[0223] A WTRU may "piggyback" an RMR request on an UL transmission, which may include one or more requests, information, and / or any other data that is not an RMR request (e.g., a WTRU may transmit an RMR request such that it accompanies an UL transmission that may possibly not be an RMR request). A WTRU may be granted UL resources for transmission of data, and such a WTRU may append an RMR request to the granted UL resources. Alternatively, or in addition, a WTRU may have UL feedback that it may wish to transmit and append to the RMR request that it may send with the UL feedback and / or one or more UCI transmissions. In an example, a WTRU may transmit a UL HARQ after a DL transmission. In an example, a WTRU may have feedback to report based on a previous RMR configuration. Such a WTRU may include, along with such feedback, a request for a change in the RMR configuration with a transmission that gives such feedback. A WTRU may indicate to the TRP that the WTRU may wish to transmit one or more RMRs in one or more HARQ feedback resources.

[0224] A WTRU may use the UL control region to indicate a request for RMR. A WTRU may autonomously schedule UL transmissions and may do so using the UL control region. A channel in the control region (or a field in the UCI transmitted in the UL control region) may be used by such a WTRU to request one or more RMR transmissions.

[0225] A WTRU request for an RMR may include one or more parameters of the RMR, such as an indication of the purpose of the RMR. Such a request may implicitly indicate one or more aspects of the RMR (e.g., by using an indication of the purpose of the RMR) depending on the resources (e.g., in time, frequency, space, and / or applicable numerology) used for the request, the codepoint, and / or any other aspects that may be associated with the transmission of the request.

[0226] The WTRU may be triggered to request transmission or reconfiguration of the RMR by one or more various criteria and / or events. Such criteria and / or events may be a change in demodulation performance. If a WTRU may not receive the RMR used for demodulation in every DL transmission, such a WTRU may determine a change in the SINR of a received DL transmission compared to a previous DL transmission.

[0227] A WTRU may determine that the performance of its decoder has changed. Such a WTRU may be triggered to request a new or reconfigured RMR that may be used for channel estimation in demodulating one or more future and / or previous DL transmissions. For example, a WTRU may be scheduled with one or more DL transmissions and may determine that its channel estimation may be out of date. Such a WTRU may buffer one or more DL transmissions and may request transmission of an RMR for use in demodulating such with one or more scheduled DL transmissions.

[0228] A WTRU may be triggered to request transmission or reconfiguration of the RMR based on a desire for retransmission. Such a WTRU may be triggered to request an RMR upon reception of a predetermined or dynamically determined number of NACKs for the same or multiple transport blocks. Such a WTRU may also, or instead, be triggered to request an RMR upon reception of a predetermined or dynamically determined number of NACKs received from the same or different TRPs. Such a WTRU may also, or instead, be triggered to request a reconfiguration of the RMR based on receiving several NACKs for the same or multiple transport blocks or from the same or different TRPs. Such a requested reconfiguration may be associated with a density different from the density of the RMR requested to be reconfigured. Such a density may enable and / or facilitate performance that may differ from the performance associated with the density of the RMR requested to be reconfigured.

[0229] The WTRU may provide an augmented HARQ feedback. The WTRU may include one or more channel estimation performance values ​​(e.g., SINR, average SINR, measurement variance, maximum measurement, minimum measurement) in the HARQ report. Such one or more channel estimation performance values ​​may be included when the HARQ report is NACK, in some examples, when such HARQ report is NACK for one or more specific retransmission values. The WTRU may, in examples, explicitly indicate in the HARQ feedback whether the WTRU desires a change in the RMR or RMR configuration, where such an RMR may be associated with one or more HARQ processes. The WTRU may indicate in the HARQ feedback report that it desires a new or modified RMR, where such a new or modified RMR may be associated with an objective. In examples, the WTRU may indicate that it desires a new or modified RMR associated with an objective of performing one or more mobility measurements, e.g., due to the performance of one or more current transport block transmissions.

[0230] The WTRU may be triggered to request transmission or reconfiguration of the RMR based on the measurement of the RMR. In an example, the WTRU may be configured with a first RMR that may be used, for example, for coarse measurements. Such a WTRU may use one or more triggers (e.g., based on one or more measurement thresholds) to determine whether a second RMR for performing finer measurements may be requested. One or more coarse measurements taken for the first RMR or the first set of RMRs may or may not be fed back by the WTRU to the TRP. If the WTRU reports one or more coarser measurements, such a report may be an implicit indication of a request for the second RMR or the second set of RMRs.

[0231] A WTRU may be triggered to request transmission or reconfiguration of an RMR based on a refined selection of one or more transmission hypotheses. In an example, a WTRU may obtain one or more measurements of a first type for a first RMR or a first set of RMRs. Based on such one or more measurements, such a WTRU may be triggered to request a second RMR or a second set of RMRs that may be used to obtain one or more measurements of a second type, for example, for fewer transmission hypotheses than the first RMR or the first set of RMRs may support. In an example, a WTRU may measure coarse channel state information for a first set of beams that may be associated with the first RMR or the first set of RMRs. Such a WTRU may use such coarse channel state information measurements, along with one or more measurement thresholds, to refine selection to a second set of potential beams that, in some examples, has fewer beams than the first set of beams. Such a WTRU may request that a TRP be transmitted a second RMR or a second set of RMRs that may be associated with the second set of potential beams and / or enable one or more finer measurements.

[0232] The WTRU may be triggered to request transmission or reconfiguration of the RMR based on an indication from the TRP. The WTRU may receive an indication from the first TRP that may instruct the WTRU to report feedback for one or more measurements of the second TRP. The WTRU may determine interference it may receive from the first TRP in one or more DL transmissions from the second TRP. Such a WTRU may request an RMR from the first TRP.

[0233] A WTRU may be triggered to request transmission or reconfiguration of an RMR based on a transmission from a TRP. The WTRU may be full-duplex radio capable. Such a WTRU may be scheduled for reception of a DL transmission from a first TRP at the same or close in time that the WTRU may also be scheduled to transmit a UL transmission to a second TRP. When scheduled for a UL transmission to the second TRP, such a WTRU may request an RMR from the first TRP.

[0234] A WTRU may be triggered to request transmission or reconfiguration of an RMR based on a change in the WTRU's RMR desires. Such a WTRU may desire a first RMR or a first set of RMRs associated with a first one or more RMR parameters based on the WTRU's status (e.g., speed). As the WTRU's status changes (e.g., its speed changes), such a WTRU may desire a change in one or more RMR parameters, or an entirely new set of one or more RMRs. The WTRU may change from using a first type of connection (e.g., optical connection) that may use a first RMR to a second type of connection (e.g., full connection) that may use a second RMR, and thus may request transmission or reconfiguration of an RMR based on such change.

[0235] The WTRU may be triggered to request transmission or reconfiguration of the RMR based on detection of a collision. The WTRU may be configured to determine when a resource collision occurs (e.g., on the sidelink) and may be configured to request an RMR associated with one or more networks and / or neighboring devices.

[0236] A WTRU may be triggered to request transmission or reconfiguration of an RMR based on WTRU autonomous mobility. A WTRU may be configured to autonomously determine a suitable TRP, TRPG, system signature, and / or cell (e.g., a set thereof). Such a WTRU may initiate a request for an RMR upon initiating a selection procedure for such a suitable TRP, TRPG, system signature, and / or cell. Such a request for an RMR may correspond to transmission of a preamble on a particular resource, such as a resource determined based on an access table.

[0237] A WTRU may be triggered to request transmission or reconfiguration of an RMR based on the WTRU's location. The WTRU may be configured to determine its location. The WTRU's location, which may be determined by the WTRU, may be associated with a granularity and / or an error margin. A WTRU may initiate (e.g., be triggered to initiate) a request for an RMR when such a WTRU may determine that it may improve its current location and / or acquire another location, e.g., a location that may be more granular, more specific, and / or have a lower error margin. The requested RMR may be used as a PRS, e.g., when the WTRU determines that a location may be acquired and / or determined.

[0238] A WTRU may have, obtain, and / or determine a coarse location and / or coarse location information. Such a WTRU may further determine that additional refinement of such coarse location and / or coarse location information may be implemented. Such a WTRU may initiate a request, for example, for purposes of increasing the frequency of such PRS and / or for purposes of having a PRS signal with one or more different characteristics (e.g., in time and / or in frequency). Such a decision for additional refinement may be based on the configuration of one or more RMRs for positioning purposes, where, for example, different RMR-PRSs may be associated with different granularities.

[0239] The WTRU may be triggered to request transmission or reconfiguration of the RMR based on radio link monitoring and / or radio link recovery. The WTRU may determine that it is and / or has experienced one or more radio link problems. This determination may be based on any of a variety of measurements, such as, but not limited to, measurements using the RMR and measurements based on methods that may be similar to those used in LTE systems (e.g., out-of-sync detection). In an example, the WTRU may determine that it may use one or more reference signals to perform radio link and / or channel quality estimation, where such estimation may be used to address one or more radio link problems. In such an example, in response to determining so, the WTRU may use one or more reference signals to perform radio link and / or channel quality estimation to address one or more radio link problems. For example, the WTRU may initiate a request for an RMR, e.g., for recovery purposes and / or for confirmation of a radio link problem.

[0240] The TRP may indicate the presence of a WTRU requested RMR, e.g., in a manner similar to that described herein for any RMR indication. The TRP may indicate an acknowledgment that a change in one or more RMR parameters that may have been requested by the WTRU has been made. For example, there may be one or more pre-determined values ​​of RMR density. A WTRU may be configured with a first value of RMR density. Such a WTRU may request a change in RMR density to a second value. The TRP may transmit an acknowledgment indicating that the requested change has been made without retransmitting all of the RMR configuration.

[0241] A WTRU may request one or more resources that it may use to transmit an RMR. An event, such as, but not limited to, any of the events described herein that may trigger a request from a WTRU for DL ​​transmission of one or more RMRs, may trigger such a WTRU to request one or more resources that may be used to transmit a UL RMR. An event that may trigger a WTRU to request a UL transmission of an RMR may be detected as a desire to transmit UL or SL data. In an example, a WTRU may be capable of WTRU autonomous transmission of data and may include an RMR to enable demodulation.

[0242] An event, such as, but not limited to, any of the events described herein, may trigger the WTRU to autonomously perform an UL transmission of the RMR. The WTRU may pre-configure resources on which it may transmit the event-triggered UL RMR. Such resources may be configured for a set of WTRUs and / or may be contention-based. Each WTRU in such a set of WTRUs may have an RMR transmission identity. One or more parameters of the RMR transmission may depend on the WTRU identity, for example, to facilitate contention resolution.

[0243] A WTRU may be configured to perform and / or report one or more measurements associated with one or more RMRs. The measurement configuration may be implemented in parallel with the configuration of one or more RMRs and / or in parallel with the configuration of one or more feedback resources. For example, a WTRU may be configured with measurements and / or one or more feedback resources and may receive an indication from a TRP instructing such WTRU to associate one or more measurements and / or one or more feedback resources with one or more RMRs. For example, a WTRU may be indicated (e.g., receive an indication message indicating) the presence of at least one instance of an RMR, at least one associated measurement (or measurement purpose), and / or at least one instance of a feedback resource. In an example, the indication message may indicate one or more of each of the presence of an instance of an RMR, an associated measurement (or measurement purpose), and an instance of a feedback resource.

[0244] The measurement configuration may be associated with an RMR that may be semi-statically configured. For example, an RMR located in a preamble or control channel may be semi-statically configured. The measurement configuration may also, or instead, be associated with an RMR that is dynamically controlled.

[0245] The measurement configuration may be used for periodic feedback, aperiodic feedback, and / or triggered feedback. The measurement configuration may include configuration and / or activation information for one or more RMRs. For example, the measurement feedback configuration may include and / or point to one or more RMR configurations.

[0246] The measurement configuration may include a subset of the RMR configuration. The measurement configuration may be applicable to a subset of resources of the RMR. In an example, the RMR may be transmitted on resources that span multiple subcarriers, and the measurement configuration may be applicable to a subset of such multiple subcarriers. The RMR may be transmitted on resources that may span multiple symbols, subframes, and / or TTIs, and the measurement configuration may be applicable to a subset of the multiple symbols, subframes, and / or TTIs.

[0247] The measurement configuration may include one or more WTRU rules for refinement of one or more RMRs. The measurement configuration may be tied to the RMR and / or RMR process. The WTRU may determine a subset of RMR instances or RMR resources associated with the RMR configuration. Such a WTRU may perform one or more measurements on such subset of RMR instances or RMR resources. Such one or more measurements may each be final measurements that may be reported back to the network. The one or more rules that the WTRU may follow when refinement of the RMR instances and / or RMR resources may be predetermined, pre-configured, and / or dynamically configured and / or determined.

[0248] The measurement configuration may include an RMR measurement configuration, which may indicate to the WTRU a relationship between multiple RMRs and / or multiple resources of the RMR (e.g., where multiple resources of the RMR may be defined as, for example, each individual resource used to prepare one instantiation of the RMR, or each instantiation of the RMR may be defined to be transmitted multiple times within a time period).

[0249] A WTRU may be configured with multiple RMRs, based on each of which such a WTRU may take the same measurement type. The RMR measurement configuration may indicate to the WTRU that all of such multiple RMRs may represent the same instantaneous channel realization. In an example, the WTRU may perform short-term channel measurements. In an example, the RMR measurement configuration may indicate to the WTRU that a set of configured RMRs (or a set of resources associated with one or more RMRs) may span, or may be assumed to span, multiple channel realizations. Such a WTRU may perform long-term channel measurements (e.g., long-term channel statistics type measurements).

[0250] A WTRU may be configured with an RMR process. Such an RMR process may be associated with a set of one or more RMR instances. A measurement configuration (e.g., a configuration given by dynamic signaling) may indicate a set of RMR instances associated with such an RMR process that may be combined (e.g., averaged) to obtain a measurement. Such a measurement configuration may indicate one or more RMRs, RMR processes, and / or RMR instances associated with the RMR and / or RMR process. Such a measurement configuration may indicate a measurement purpose for at least one of the RMRs, RMR processes, or RMR instances. For example, such a measurement configuration may include multiple RMRs (or indications thereof), each of which may be associated with a different measurement purpose (e.g., a first RMR may be used by the WTRU to measure signal strength, a second RMR may be used by the WTRU to measure Doppler, a third RMR may be used by the WTRU to measure channel occupancy, etc.).

[0251] A measurement configuration may include one or more measurement types. The measurement types may be, but need not be, similar to a measurement purpose, such as, but not limited to, the measurement purposes described herein. The measurement type may indicate to the WTRU that a (e.g., specific) CSI measurement may be performed for an associated RMR. The measurement type may be obtained based on a function of a set of measurements that may be taken of one or more RMRs. For example, a WTRU may obtain a first measurement for a first RMR (or RMR process or RMR instance) and a second measurement for a second RMR (or RMR process or RMR instance). The measurement type indicated in the measurement configuration may indicate to such a WTRU a function that the WTRU may use to combine the first and second measurements to determine or generate a third measurement. Such a third measurement may be an intended result of the measurement configuration and / or may be used to determine whether a triggering event or criterion has been met, where such a triggering event or criterion, if met, may trigger a measurement report.

[0252] The measurement configuration may include one or more measurement feedback resources, which may be used by the WTRU to report, for example, periodic, aperiodic, and / or triggered feedback.

[0253] A measurement configuration may include an indication of a purpose of the measurement or associated procedure. A measurement configuration may indicate and / or be associated with a single purpose associated with one or more RMRs. Alternatively, or in addition, a measurement configuration may indicate and / or be associated with multiple purposes associated with one or more RMRs. In an example, the WTRU may determine an association between a measurement configuration and a procedure (e.g., demodulation, mobility, radio link monitoring, etc.).

[0254] The WTRU may not store and / or possibly maintain access to one or more measurements that the WTRU may have performed, accessed, and / or obtained. A measurement configuration may include one or more measurement triggers, each of which may trigger an associated WTRU to perform one or more measurements.

[0255] A measurement trigger configured in the first measurement configuration may be associated with one or more results of one or more measurements that may be performed based on the second measurement configuration. Such a second measurement configuration may configure the WTRU to perform one or more measurements, such as, but not limited to, a collection of long-term channel statistics over a second RMR that may be associated with the second measurement configuration. Based on such one or more such measurements and associated triggers, the WTRU may be triggered to perform one or more measurements that may be configured in the first measurement configuration. Additionally or alternatively, the WTRU may be triggered by a trigger that may be provided in the first measurement configuration, The measurement configuration may indicate to the WTRU a list of one or more measurements that may be independent RMRs, RMR processes, and / or RMR instances. Alternatively, such list may be of one or more measurements that may not be independent RMRs, RMR processes, and / or RMR instances. The measurement configuration may indicate one or more measurement triggers that may be used to trigger a decision whether a subsequent measurement should be obtained. In an example, a WTRU may be configured with a first measurement for a first RMR and a second measurement for a second RMR. Such a WTRU may also be configured with a measurement trigger that may be based on such first measurement, such as, for example, a trigger based on achieving a threshold. When such a first measurement meets a trigger condition of such measurement trigger or possibly activates such measurement trigger (e.g., where such a first measurement meets or exceeds a threshold), the WTRU may perform and / or calculate a third measurement. Such a third measurement may be of a third RMR and / or a function of the first and / or second measurements.

[0256] In an example, the WTRU may receive downlink control information (e.g., DCI) that may trigger measurements. Such DCI may include an RMR configuration and / or an identification of an applicable RMR configuration. Such DCI may also, or instead, include scheduling information for reporting that may be associated with the triggered measurements.

[0257] A measurement configuration may include one or more report triggers. The WTRU may not report all measurements configured by the measurement configuration. Such a measurement configuration may provide one or more criteria that may be used to trigger the WTRU to report measurements. In an example, the WTRU may receive downlink control information (e.g., DCI) that may trigger a measurement report. Such DCI may include an identification of an applicable RMR configuration. Such DCI may also, or instead, include scheduling information that may be associated with a report that may be associated with the triggered measurement.

[0258] A measurement configuration may include an indication of one or more associated TRPs, TRPGs, system signatures, cells, and device identities. Such a measurement configuration may give a TRP or set of TRPs and / or a set of WTRUs or WTRU devices to which such measurements may be applied.

[0259] The measurement configuration may include a random access configuration. The WTRU may be configured with one or more RMRs and / or information associated therewith. Each such RMR may assist or facilitate one or more of cell, TRP, TRPG, and / or system signature selection.

[0260] A WTRU may be configured with one or more access-related parameters, such as access rights, random access parameters, any of which may also be associated with one or more configured RMRs or associated with configured information at the WTRU. Such a WTRU may perform one or more measurements using such one or more RMR configurations or information. Such a WTRU may determine whether one or more of such measurements have produced suitable or possibly compliant results.

[0261] Such a WTRU may compare or possibly use access-related parameters associated with an RMR to determine whether a configuration associated with such RMR may correspond to an associated cell, TRP, TRPG, and / or system signature. If such a cell, TRP, TRPG, and / or system signature is determined to correspond to such an RMR, the WTRU may use such parameters to initiate access of such RMR, and in some examples, perform random access thereof. Such a WTRU may perform such comparison and / or use of access-related parameters to determine whether a configuration associated with any such RMR corresponds to a cell, TRP, TRPG, and / or system signature, as well as to determine whether to initiate access (e.g., random access) of any such RMR using the associated parameters.

[0262] In a WTRU autonomous mobility example, a WTRU may use such an RMR to determine whether such WTRU should consider a cell, TRP, TRPG, and / or system signature associated with such an RMR as a serving cell, serving TRP, serving TRPG, and / or serving system signature, respectively ("serving set"). Such a WTRU may determine that different RMRs should be associated with serving cells, serving TRPs, serving TRPGs, and / or serving system signatures.

[0263] If an RMR may be added to a serving set, the WTRU may determine whether the cell, TRP, TRPG, and / or system signature associated with such added RMR may be part of the same area as the cell, TRP, TRPG, and / or system signature previously associated with such serving set. If not, such WTRU may use access parameters associated with such added RMR to perform one or more functions, such as, but not limited to, a location update, which may be RAN-based, in examples.

[0264] The WTRU may be configured with a measurement configuration via higher layer signaling. The WTRU may be configured in a DL transmission mode. Such a transmission mode may include one or more of a TTI duration, a signal structure, and an RMR. The measurement configuration may be applied in parallel with the transmission mode configuration. Such a measurement configuration may provide an indication of the purpose (e.g., demodulation) of the RMR.

[0265] The measurement configuration may be dynamically controlled. The dynamic measurement configuration may be performed or possibly implemented by a DCI (or other control channel) that may configure the RMR. The DCI may be transmitted in the control domain to provide the measurement configuration. In an example, a dedicated DCI that may be used for the RMR configuration may be used for the measurement configuration. In an example, a first (e.g., long-term or wideband) DCI may configure one or more RMRs, and a second (e.g., short-term or sub-band) DCI may provide one or more measurement configurations. Such one or more RMRs may exist across resources that may be covered by such a first DCI, and such one or more measurement configurations may be applied to resources (e.g., subframes or symbols, subcarriers, or sub-bands) covered by such a second DCI.

[0266] The dynamic measurement configuration may be performed or possibly implemented by a DCI (or other control channel) that may schedule a DL transmission. The DCI that schedules the DL transmission may include an associated measurement configuration. Such a measurement configuration may be used to map an RMR that may be used for demodulation of the associated DL transmission.

[0267] The dynamic measurement configuration may be performed or possibly implemented by a MAC Control Element ("MAC CE"). The WTRU may receive a MAC CE that may include one or more measurement configurations. Such a MAC CE may be included in a RAR. Such a MAC CE may be received on a downlink transmission. The WTRU may determine that such one or more measurement configurations included with such received MAC CE may be applicable to a SOM that may be associated with a physical channel, a transport channel, and / or a control channel associated with the downlink transmission that included such MAC CE.

[0268] The WTRU may report measurements in resources that may be configured by the TRP. The configuration of feedback resources may be performed within the measurement configuration. The WTRU may report information based on its own measurements and / or based on reporting measurements that may address one or more purposes, such as, but not limited to, any one or more purposes that may be described herein and for which the WTRU may perform measurements.

[0269] The WTRU may report a value that may be based on the measurements performed. The objectives associated with such measurements may provide one or more various feedback reports, each of which may depend on the measurements performed. In an example, the WTRU may report a quantized version of the measurements taken. In an example, the WTRU may provide a feedback report based on one or more measurement thresholds associated with one or more obtained measurements.

[0270] The WTRU may report different levels and / or types of channel utilization depending on the measurements taken. Such a WTRU may be configured with an RMR (e.g., a blanked RMR) in which it may attempt to detect interference and interference types. Such a WTRU may feed back the type of channel utilization that may be encountered on the configured RMR. Alternatively, or additionally, such a WTRU may feed back the type of channel structure that may be encountered on the configured RMR.

[0271] The value reported by the WTRU may be based on one or more sub-RMR measurements. The WTRU may be configured with an RMR or RMR process for which it may perform one or more measurements. Such a WTRU may be configured to determine, or may autonomously determine, one or more subsets of the configured RMR or RMR process and may perform one or more individual measurements on such one or more subsets. Such a WTRU may report an overall measurement (e.g., an average measurement) for all resources of the configured RMR or RMR process. Alternatively, or additionally, such a WTRU may report one or more individual sub-RMR or sub-RMR process measurements. In an example, a WTRU may be configured with an RMR process for which interference should be measured. Such a WTRU may determine that interference is not uniform across resources of the RMR process. Such a WTRU may feed back multiple interference values. Such interference values ​​may be fed back with an indication of the respective associated RMR resource. Faster adaptation to channels with unexpected interference changes (e.g., due to URLLC transmissions) may be facilitated in such an example.

[0272] A WTRU may be configured with an RMR that may span multiple resources, where each such resource may be associated with a different antenna port. Such a WTRU may determine a subset of resources for which measurements may be valid. Such a WTRU may also, or instead, report to the network the subset of resources of the RMR and / or RMR process for which measurements may be valid. In an example, such a WTRU may use one or more sub-RMR resource identifiers with such reporting.

[0273] The WTRU may report one or more requests for one or more new and / or updated RMRs.

[0274] The WTRU may report one or more sets of RMR and / or RMR sub-resources for which measurements may be valid. The WTRU may indicate whether such measurements may be assumed for a single channel realization or for multiple channel realization capabilities.

[0275] A WTRU may provide an indication (or indications) of each RMR of a set of one or more RMRs based on which such a WTRU may have performed one or measurements that the WTRU may use to perform functions that may determine and / or obtain measurements that should be reported. A WTRU may be configured with a first RMR for which a first measurement may be performed, and a second RMR for which a second measurement may be performed. Such a WTRU may be configured to perform functions that may use such first and second measurements to obtain a third measurement and / or result.

[0276] A WTRU may report one or more sets of resources for which measurements may be valid (e.g., symbols, subframes, subframe sets, TTIs, frames, configurable units of time, subcarriers, subbands, configurable frequency blocks, etc.). Such a WTRU may report wideband and / or subband measurements. Such a WTRU may also, or instead, report long-term and / or short-term measurements. The measurement types (e.g., RI, CQI, PMI, etc.) that may be reported by such a WTRU may be similarly and / or separately defined for each of the one or more long-term measurements and the one or more short-term measurements. The one or more long-term measurements may indicate the statistical performance of the channel. The WTRU may report the average use of such a channel by other TRPs and / or WTRUs. The one or more short-term measurements may indicate one or more instantaneous channel characteristics. The WTRU may report whether the channel may be currently in use.

[0277] The WTRU may report the reason why a measurement may be triggered. Such a report may indicate when the trigger may not be a function of the measurement. In an example, a first measurement may be reported with a second measurement triggering the transmission of a feedback report.

[0278] The WTRU may report the RMR ID and / or the associated TRP, TRPG, system signature, cell, and / or WTRU ID.

[0279] The feedback resource may be included in the measurement configuration. The feedback resource may be transmitted independent of the measurement resource. In an example, a WTRU may receive an RMR configuration that may indicate activation of an RMR. Such a WTRU may receive a measurement configuration that may indicate activation of measurements to be performed on an RMR associated with the received RMR configuration. Such a WTRU may receive a feedback resource configuration, after receiving such a measurement configuration in some examples, that may indicate one or more resources on which measurements may be fed back.

[0280] Although the feedback resources and / or an indication thereof may be included in the measurement configuration and / or provided independently of the measurement resources, the feedback resources may also or instead be configured by a DCI. For example, a DCI may be defined as indicating one or more feedback resources to a WTRU. Such a DCI may or may not be dedicated to indicating one or more feedback resources to a WTRU. A two-part approach may be used, where a first (e.g., long-term or wideband) DCI may be used to provide one or more feedback parameters and a second (e.g., short-term or sub-band) DCI may be used to provide one or more other feedback parameters. Such a second DCI may be used to dynamically activate or deactivate one or more feedback resources on a subset of channel resources (e.g., a subset of the total bandwidth or a subset of symbols).

[0281] The feedback resources may also, or instead, be configured by and / or included with DCI that may be used to grant UL resources. Such UL resources may be used for UL data transmission. Such UL resources may be used for transmission of uplink control information (UCI).

[0282] The feedback resources may also or instead be configured by and / or included in a DCI for an independent subframe transmission. Such a DCI may be transmitted in a DL control region of the independent subframe. Such a DCI may serve one or more purposes. In an example, such a DCI may allocate DL resources and / or UL feedback resources. Such a DCI may include a feedback configuration that may provide resources that may be used to feed back measurements.

[0283] The DCI may be used to dynamically activate or deactivate one or more feedback resources on a subset of channel resources (e.g., a subset of the total bandwidth, a subset of symbols). The DCI may indicate an index into a configuration that may be associated with one or more objectives, including but not limited to any of the objectives described herein.

[0284] A WTRU may be configured to report measurements (e.g., CSI reports) based on a set of dependent reference measurement resources, measurement configurations, and / or feedback resource configurations. A WTRU may also, or instead, be configured with and / or include an indication of one or more reference measurement resources, measurement configurations, and / or feedback resource configurations, each of which may be unrelated. Such configurations may be implemented in a semi-static manner, e.g., via higher layer signaling. A WTRU may have a set of reference measurement resources, a set of measurement configurations, and / or a set of feedback resources. Such a WTRU may be configured, for example, to dynamically associate one element from each such set (e.g., one reference measurement resource, one measurement configuration, and one feedback resource) with a measurement reporting process and / or a measurement report.

[0285] A WTRU may be configured with at least two RMRs, each of which may span different and, in some examples, independent resource elements (for illustrative purposes, RMR A and RMR B may be referred to herein as two examples of such at least two RMRs). Such a WTRU may be configured, for example, with two measurement configurations (e.g., a first measurement configuration “1” for long-term CSI reporting that is tied to a first set of measurement report triggers, and a second measurement configuration “2” for short-term CSI reporting that is tied to a second set of measurement report triggers). Such a WTRU may be configured, for example, with at least three feedback resources (for illustrative purposes, X, Y, Z may be referred to herein as three examples of such at least three feedback resources). Each such feedback resource may include or indicate a reporting occasion and / or time / frequency / code / beam resource that may differ from the reporting occasion and / or time / frequency / code / beam resource indicated in another such feedback resource.

[0286] Such a WTRU may be indicated or instructed to combine one or more resource elements, measurement configurations, and / or feedback resources dynamically and / or via higher layer signaling. Such a combination may be referred to as a measurement reporting process. In an example, a WTRU may be configured to combine RMR A, measurement configuration 2, and feedback resource Y into a measurement reporting process. The validity of such a measurement reporting process may be applicable to a single occurrence of an RMR transmission, measurement occurrence, and / or feedback transmission. Alternatively, the validity of such a measurement reporting process may be applicable to multiple occurrences of each of an RMR transmission, measurement occurrence, and / or feedback transmission (e.g., in a semi-persistent manner).

[0287] The configuration or instruction of a measurement reporting process may indicate whether such a measurement reporting process is one-shot (e.g., a one-time measurement resource, measurement configuration, and / or feedback report, or any combination thereof), multi-shot (e.g., a set of multiple measurement resources, measurement configurations, and / or feedback reports, or combinations thereof), or periodic (e.g., multiple periodic measurement resources, measurement configurations, and / or feedback reports, or combinations thereof, each of which may be valid and / or used until further reconfiguration). The configuration or instruction of such a measurement reporting process may also or instead indicate activation or deactivation of a multi-shot or periodic process.

[0288] A WTRU may be configured to perform one or more measurements on one or more RMRs. Such a WTRU may be configured with one or more triggers that the WTRU may use to determine whether such one or more measurements may be fed back. The measurement feedback trigger may be based on an associated measurement. In an example, the measurement feedback trigger may be based on whether an associated measurement may meet or exceed an offset and / or threshold. In an example, the measurement feedback trigger may be based on whether an associated measurement meets, is above or below another measurement (e.g., a measurement that may be obtained from another RMR), in addition to an offset, in some examples.

[0289] The trigger criteria may be evaluated for each RMR or set of RMRs. In an example, the trigger criteria may be evaluated for some or all RMRs activated with and / or associated with a given TRP, TRPG, system signature, cell, and / or WTRU. The WTRU may initiate the transmission of feedback when a measured offset for a first RMR may be "better" than or compare favorably with a measured offset of a second RMR, in an example, by an offset value. Such a first RMR and second RMR may be associated with the same TRP and / or cell.

[0290] Such one or more measurements, triggers, and / or evaluations may be used, for example, for link adaptation purposes. The WTRU may trigger a feedback transmission when the first RMR may have a measured offset that may meet or exceed a threshold and / or when the measured offset of the first RMR becomes "better" or possibly compares favorably with the measured offset for the second RMR. Such a first RMR may be associated with a first TRP or set of TRPs (e.g., a first system signature). Such a second RMR may be associated with a serving TRP or set of serving TRPs (e.g., a second system signature). Such feedback may be used for network controlled mobility purposes.

[0291] Such one or more measurements, triggers, and / or evaluations may be used, for example, to determine whether the TB may have been successfully decoded. If the WTRU determines (e.g., using such one or more measurements, triggers, and / or evaluations) that the TB may not have been properly decoded and / or that a NACK may be required, the WTRU may be configured to perform one or more measurements on the RMR and may feed back such one or more measurements. In an example, such feedback may facilitate the TRP to perform link adaptation, for example, for retransmission of the TB.

[0292] The RMR may reuse one or more resources that may have been used for transmission of the TB. The WTRU may use one or more data REs to perform one or more measurements. Such a WTRU may be triggered to feed back such one or more measurements, e.g., if the WTRU determines that a TB may have been properly decoded, to ensure the validity of such measurements.

[0293] The WTRU may initiate mobility-related procedures instead of or in addition to transmitting uplink feedback. Such initiation of mobility-related procedures may be based on one or more measurements, triggers, and / or evaluations, as described herein.

[0294] Although the features and elements are described above in certain combinations, one skilled in the art will appreciate that each feature or element may be used alone or in any combination with the other features and elements. Also, the methods described 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 over wired or wireless connections) and computer-readable storage media. Examples of computer-readable storage media include, but are not limited to, ROM, 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.

Claims

1. 1. A wireless transmit / receive unit (WTRU) comprising a processor and a memory, the processor and the memory comprising: receiving configuration information for a plurality of reference signal measurement resources (RMRs), the configuration information indicating a respective resource element associated with each respective RMR of the plurality of RMRs; receiving measurement configuration information, the measurement configuration information indicating that a first set of RMRs of the plurality of RMRs is to be used for making a first measurement, the measurement configuration information indicating feedback resources for reporting feedback derived based on the first measurement made using the first set of RMRs, and the measurement configuration information indicating that a second measurement made using a second set of RMRs of the plurality of RMRs is to not be reported; performing the first measurement using the first set of RMRs in accordance with the measurement configuration information; performing the second measurement using the second set of RMRs in accordance with the measurement configuration information; transmitting a measurement report based on the first measurement performed using the first set of RMRs using the feedback resource; A WTRU configured to perform the following:

2. The WTRU of claim 1 , wherein the WTRU is configured to locally use the second measurements made using the second set of RMRs to assist downlink reception.

3. The WTRU of claim 2, wherein the WTRU is configured to locally use the second measurements made using the second set of RMRs to assist downlink reception by being configured to perform channel estimation using the second measurements made using the second set of RMRs.

4. 2. The WTRU of claim 1, wherein the measurement configuration information indicates a type of measurement to be performed for the first measurement, the type of measurement including one or more of a channel state information (CSI) measurement or a received power measurement.

5. The WTRU of claim 1 , wherein the WTRU is configured to select a preferred beam using the second measurement made using the second set of RMRs.

6. The WTRU of claim 1 , wherein the configuration information for the multiple RMRs is received via radio resource control (RRC) signaling.

7. The WTRU of claim 6 , wherein at least one of the first set of RMRs or the second set of RMRs is activated using dynamic signaling.

8. 1. A method implemented by a wireless transmit / receive unit (WTRU), comprising: receiving configuration information for a plurality of reference signal measurement resources (RMRs), the configuration information indicating a respective resource element associated with each respective RMR of the plurality of RMRs; receiving measurement configuration information, the measurement configuration information indicating that a first set of RMRs of the plurality of RMRs is to be used for making a first measurement, the measurement configuration information indicating feedback resources for reporting feedback derived based on the first measurement made using the first set of RMRs, and the measurement configuration information indicating that a second measurement made using a second set of RMRs of the plurality of RMRs is to not be reported; performing the first measurement using the first set of RMRs in accordance with the measurement configuration information; performing the second measurement using the second set of RMRs in accordance with the measurement configuration information; transmitting a measurement report based on the first measurement performed using the first set of RMRs using the feedback resource; A method for providing the above.

9. The method of claim 8, wherein the WTRU locally uses the second measurements made with the second set of RMRs to assist downlink reception.

10. 10. The method of claim 9, wherein the WTRU uses the second set of RMRs to perform channel estimation and locally uses the second measurements made using the second set of RMRs to assist downlink reception.

11. 9. The method of claim 8, wherein the measurement configuration information indicates a type of measurement to be performed for the first measurement, the type of measurement including one or more of a channel state information (CSI) measurement or a received power measurement.

12. The method of claim 8, wherein the WTRU selects a preferred beam using the second measurement made using the second set of RMRs.

13. The method of claim 8 , wherein the configuration information for the multiple RMRs is received via Radio Resource Control (RRC) signaling.

14. The method of claim 13 , wherein at least one of the first set of RMRs or the second set of RMRs is activated using dynamic signaling.

15. A network node comprising a processor and a memory, the processor and the memory comprising: transmitting configuration information for a plurality of reference signal measurement resources (RMRs) to a wireless transmit / receive unit (WTRU), the configuration information indicating a respective resource element associated with each respective RMR of the plurality of RMRs; sending measurement configuration information to the WTRU, the measurement configuration information indicating that a first set of RMRs of the plurality of RMRs will be used by the WTRU to make a first measurement, the measurement configuration information indicating feedback resources to be used by the WTRU to report feedback based on the first measurement made using the first set of RMRs, and the measurement configuration information indicating that a second measurement made by the WTRU using a second set of RMRs of the plurality of RMRs will not be reported; receiving a measurement report using the feedback resource indicating measurements based on the first measurements made by the WTRU using the first set of RMRs; A network node configured to:

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