Open loop HARQ in wireless systems

Abstract

To provide systems, methods, and means associated with logical channel prioritization.SOLUTION: A WTRU may be configured to perform logical channel prioritization. The WTRU may receive an indication (e.g., a mapping) that indicates an association between a first HARQ process ID and a first HARQ processing type and between a second HARQ process ID and a second HARQ processing type. The WTRU may receive an indication (e.g., a mapping) that indicates an association between a first logical channel and the first HARQ processing type and between a second logical channel and the second HARQ processing type. The WTRU may receive a HARQ process ID indication. The WTRU may determine a HARQ processing type associated with the HARQ process ID. The WTRU may determine a logical channel available for a transmission.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] <CROSS REFERENCE TO RELATED APPLICATIONS> This application claims the benefit of U.S. Provisional Patent Application No. 62 / 840,987, filed August 30, 2019, and U.S. Provisional Patent Application No. 62 / 886,075, filed August 13, 2019, the contents of which are incorporated herein by reference.

[0002] This application relates to open-loop HARQ in wireless systems. [Background technology]

[0003] Mobile communications using wireless communications continues to evolve. The fifth generation may be referred to as 5G. The previous (e.g., legacy) generation of mobile communications may be, for example, fourth generation (4G) Long Term Evolution (LTE).

[0004] Round Trip Delay (RTD) for communications in non-terrestrial networks may be much higher than RTD for communications in terrestrial networks. For example, the RTD for a low Earth orbit (LEO) satellite at an altitude of about 600 kilometers may be as much as about 28 milliseconds. The RTD for a medium Earth orbit (MEO) satellite at an altitude of about 10,000 kilometers may be as much as about 190 milliseconds. The RTD for a geostationary Earth orbit (GEO) satellite may be as much as about 545 milliseconds. Such large RTD times have various effects on the ability of a wireless transmit / receive unit (WTRU) to maintain support for high data rate services. Summary of the Invention [Problem to be solved by the invention]

[0005] Systems, methods, and means associated with logical channel prioritization are provided. [Means for solving the problem]

[0006] Systems, methods, and means associated with logical channel prioritization are described herein. A WTRU may be configured to perform logical channel prioritization. The WTRU may receive an indication (e.g., a mapping) indicating an association between a first hybrid automatic repeat request (HARQ) process identifier (ID) and a first HARQ process type, and an association between a second HARQ process ID and a second HARQ process type. The WTRU may receive an indication (e.g., a mapping) indicating an association between a first logical channel and a first HARQ process type, and an association between a second logical channel and a second HARQ process type. The WTRU may receive an uplink (UL) grant indicating the HARQ process ID. The WTRU may determine a HARQ process type associated with the HARQ process ID. The WTRU may determine logical channels available to be used for transmission. The logical channels available to be used for transmission may be determined based on, for example, a HARQ process type associated with the HARQ process ID. The WTRU may send the transmission using the logical channels that are determined to be available.

[0007] The WTRU may determine, for example, that a first logical channel is available for use for a transmission if the HARQ process ID is associated with a first HARQ process type (e.g., for determining the logical channels available for use based on the HARQ process type associated with the HARQ process ID). The WTRU may determine, for example, that a second logical channel is available for use for a transmission if the HARQ process ID is associated with a second HARQ process type (e.g., for determining the logical channels available for use based on the HARQ process type associated with the HARQ process ID). The WTRU may determine, for example, that a first logical channel is not available for use for a transmission if the HARQ process ID is not associated with the first HARQ process type (e.g., for determining the logical channels available for use based on the HARQ process type associated with the HARQ process ID). The WTRU may determine that the second logical channel is not available for use for a transmission (e.g., for determining the logical channel available for use based on the HARQ process type associated with the HARQ process ID), for example, if the HARQ process ID is not associated with the second HARQ process type.

[0008] Systems, methods, and means associated with logical channel prioritization are described herein. A WTRU may be configured to perform logical channel prioritization. The WTRU may receive a mapping indicating an association between a first hybrid automatic repeat request (HARQ) process identifier (ID) and a first HARQ process type, and an association between a second HARQ process ID and a second HARQ process type. The WTRU may receive a mapping indicating an association between a first logical channel and a first HARQ process type, and an association between a second logical channel and a second HARQ process type. The WTRU may receive an uplink (UL) grant indicating the HARQ process ID. The WTRU may determine a HARQ process type associated with the HARQ process ID. The WTRU may determine a logical channel restriction that restricts the logical channels from being used for transmission. The logical channel restriction may be determined based on the HARQ process type associated with the HARQ process ID.

[0009] The WTRU may, for example, restrict a first logical channel from being used for transmission if the HARQ process ID is associated with a first HARQ process type (e.g., for determining logical channel restriction based on the HARQ process type associated with the HARQ process ID) and / or may, for example, restrict a second logical channel from being used for transmission if the HARQ process ID is associated with a second HARQ process type.

[0010] The first HARQ processing type may be, for example, a closed-loop HARQ processing type, and the second HARQ processing type may be, for example, an open-loop HARQ processing type. The first HARQ processing type may be associated with a first power parameter, and the second HARQ processing type may be associated with a second power parameter. The transmission may be, for example, a scheduling request (SR). The WTRU may transmit a transmission (e.g., an SR) using (e.g., on) a logical channel that is not restricted in use. The transmission may be associated with a power parameter. The power parameter may be the first power parameter or the second power parameter. The first power parameter may be a first power offset, a first fractional power value, a first transmit power command (TPC) command, or a first target power. The second power parameter may be a second power offset, a second fractional power value, a second TPC command, or a second target power.

[0011] Systems, methods, and means for determining and applying various types of Hybrid Automatic Request (HARQ) processes to downlink and / or uplink processes are described herein. A WTRU may determine a first HARQ process type (HPT) associated with a first HARQ process and a second HARQ process type associated with a second HARQ process. The first HARQ process type and / or the second HARQ process type may be determined, for example, based on semi-static configuration and / or received dynamic signaling. For example, the first HARQ process type and / or the second HARQ process type may be pre-configured.

[0012] The WTRU may apply a first HARQ process type to a first HARQ process associated with a first transmission and may apply a second HARQ process type to a second HARQ process associated with a second transmission. The first HARQ process type or the second HARQ process type may be, for example, a closed-loop HARQ process, an open-loop HARQ process, or a stateless HARQ process. The first HARQ process type and / or the second HARQ process type may be applied based on, for example, a type of scheduling information received from the network.

[0013] The first or second HARQ process type may be applied to the first transmission, for example, for the duration of an RRC connection or for the duration of an RRC configuration. The first and / or second HARQ process type may be specific to a serving cell. The WTRU may receive a configuration for the first and / or second HARQ process type, for example, via system information. The first or second HARQ process type may be for one or more HARQ process identifiers.

[0014] The WTRU may determine a HARQ behavior associated with one or more configured grants based on the HARQ configuration. The WTRU may determine a HARQ behavior associated with one or more configured grants based on, for example, a HARQ configuration for a transmission associated with a dynamic (e.g., unconfigured) grant. Effect of the Invention

[0015] Systems, methods, and means associated with novel logical channel prioritization are provided. [Brief description of the drawings]

[0016] [Figure 1A]FIG. 1 is a system diagram illustrating an example communication system in which one or more disclosed embodiments may be implemented. [Figure 1B] 1A is a system diagram illustrating an example wireless transmit / receive unit (WTRU) that may be used within the communications system illustrated in FIG. 1A, in accordance with an embodiment. [Figure 1C] 1B is a system diagram illustrating an example Radio Access Network (RAN) and an example Core Network (CN) that may be used within the communications system illustrated in FIG. 1A in accordance with an embodiment. [Figure 1D] FIG. 1B is a system diagram illustrating a further example RAN and a further example CN that can be used within the communication system illustrated in FIG. 1A, according to an embodiment. [Diagram 2] 1 illustrates an example Next Generation Radio Access Network (NG-RAN) architecture in a non-terrestrial network with a bent pipe payload. [Diagram 3] 1 illustrates an exemplary NG-RAN architecture in a non-terrestrial network with gNB-DU processed payload. [Figure 4] 1 illustrates an exemplary NG-RAN architecture in a non-terrestrial network with gNB processed payload. [Diagram 5] 1 illustrates an embodiment associated with logical channel restrictions. [Figure 6] 13 illustrates an example of a WTRU determining a HARQ type for resources in a configured grant. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] 1A illustrates an example communication system 100 in which one or more disclosed embodiments may be implemented. The communication system 100 may be a multiple access system that provides content, such as voice, data, video, messaging, broadcast, etc., to multiple wireless users. The communication system 100 may enable the multiple wireless users to access such content through sharing of system resources, including wireless bandwidth. For example, the communication system 100 may utilize one or more channel access methods, such as Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal FDMA (OFDMA), Single Carrier FDMA (SC-FDMA), Zero-Tailed Unique Word Discrete Fourier Transform Spread OFDM (ZT UW DTS-S-OFDM), Unique Word OFDM (UW-OFDM), Resource Block Filtered OFDM, and Filter Bank Multi-Carrier (FBMC).

[0018] 1A, the communications system 100 may include wireless transmit / receive units (WTRUs) 102a, 102b, 102c, 102d, a RAN 104 / 113, a CN 106, a public switched telephone network (PSTN) 108, the Internet 110, and other networks 112, although it will be recognized that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, and / or network elements. Each of the WTRUs 102a, 102b, 102c, 102d may be any type of device configured to operate and / or communicate in a wireless environment. By way of example, the WTRUs 102a, 102b, 102c, 102d, any of which may be referred to as a “station” and / or “STA,” may be configured to transmit and / or receive wireless signals and may include user equipment (UE), mobile stations, fixed or mobile subscriber units, subscription-based units, pagers, cellular phones, personal digital assistants (PDAs), smartphones, laptops, netbooks, personal computers, wireless sensors, hotspots or Mi-Fi devices, Internet of Things (IoT) devices, watches or other wearables, head mounted displays (HMDs), vehicles, drones, medical devices and applications (e.g., remote surgery), industrial devices and applications (e.g., robots and / or other wireless devices operating in industrial and / or automated processing chain situations), consumer electronics devices, and devices operating on commercial and / or industrial wireless networks, etc. Any of the WTRUs 102a, 102b, 102c, 102d may be referred to interchangeably as a UE.

[0019] The communication system 100 may also include a base station 114a and / or a base station 114b. Each of the base stations 114a, 114b may be any type of device configured to wirelessly interface with at least one of the WTRUs 102a, 102b, 102c, 102d to facilitate access to one or more communication networks, such as the CN 106, the Internet 110, and / or other networks 112. By way of example, the base stations 114a, 114b may be a base transceiver station (BTS), a NodeB, an eNodeB, a home NodeB, a home eNodeB, a gNB, a NR NodeB, a site controller, an access point (AP), a wireless router, and the like. Although the base stations 114a, 114b are each depicted as a single element, it will be understood that the base stations 114a, 114b may include any number of interconnected base stations and / or network elements.

[0020] The base station 114a may be part of the RAN 104 / 113, which may also include other base stations and / or network elements (not shown), such as a base station controller (BSC), a radio network controller (RNC), relay nodes, etc. The base station 114a and / or the base station 114b may be configured to transmit and / or receive wireless signals on one or more carrier frequencies, which may be referred to as a cell (not shown). These frequencies may be in the licensed spectrum, the unlicensed spectrum, or a combination of the licensed and unlicensed spectrum. A cell may provide coverage for wireless services in a particular geographic area, which may be relatively fixed or may change over time. A cell may be further divided into cell sectors. For example, the cell associated with the base station 114a may be divided into three sectors. Thus, in one embodiment, the base station 114a may include three transceivers, one for each sector of the cell. In an embodiment, the base station 114a may utilize multiple-input multiple-output (MIMO) technology and may utilize multiple transceivers for each sector of the cell. For example, beamforming may be used to transmit and / or receive signals in desired spatial directions.

[0021] The base stations 114a, 114b may communicate with one or more of the WTRUs 102a, 102b, 102c, 102d over an air interface 116, which may be any suitable wireless communication link (e.g., radio frequency (RF), microwave, centimeter wave, micrometer wave, infrared (IR), ultraviolet (UV), visible light, etc.). The air interface 116 may be established using any suitable radio access technology (RAT).

[0022] More specifically, as mentioned above, the communication system 100 may be a multiple access system and may employ one or more channel access schemes, such as CDMA, TDMA, FDMA, OFDMA, and SC-FDMA. For example, the base station 114a and the WTRUs 102a, 102b, 102c in the RAN 104 / 113 may implement a radio technology such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which may establish the air interface 116 using Wideband CDMA (WCDMA). WCDMA may include communication protocols such as High Speed ​​Packet Access (HSPA) and / or Evolved HSPA (HSPA+). HSPA may include High Speed ​​Downlink (DL) Packet Access (HSDPA) and / or High Speed ​​Uplink (UL) Packet Access (HSUPA).

[0023] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as Evolved UMTS Terrestrial Radio Access (E-UTRA), which may establish the air interface 116 using Long Term Evolution (LTE), and / or LTE Advanced (LTE-A), and / or LTE Advanced Pro (LTE-A Pro).

[0024] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may establish the air interface 116 using New Radio (NR) and may implement a radio technology such as NR radio access.

[0025] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement multiple radio access technologies. For example, the base station 114a and the WTRUs 102a, 102b, 102c may implement both LTE and NR radio access, e.g., using a dual connectivity (DC) principle. Thus, the air interface utilized by the WTRUs 102a, 102b, 102c may be characterized by multiple types of radio access technologies and / or transmissions transmitted to / from multiple types of base stations (e.g., eNBs and gNBs).

[0026] In other embodiments, the base station 114a and the WTRUs 102a, 102b, 102c may implement a wireless technology such as IEEE 802.11 (i.e., Wireless Fidelity (WiFi)), IEEE 802.16 (i.e., Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 1X, CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System for Mobile Communications (GSM), Enhanced Data Rates for GSM Evolution (EDGE), and GSM EDGE (GERAN).

[0027] 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 localized area, such as an office, a home, a vehicle, a campus, an industrial facility, an air corridor (e.g., used by drones), and a roadway. In one embodiment, the base station 114b and the WTRUs 102c, 102d may implement a wireless technology such as IEEE 802.11 to establish a wireless local area network (WLAN). In an embodiment, the base station 114b and the WTRUs 102c, 102d may implement a wireless technology such as IEEE 802.15 to establish a wireless personal area network (WPAN). In yet another embodiment, the base station 114b and the WTRUs 102c, 102d may utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, LTE-A Pro, NR, etc.) to establish a picocell or femtocell. 1A, the base station 114b may have a direct connection to the Internet 110. Thus, the base station 114b may not need to access the Internet 110 via the CN 106 / 115.

[0028] The RAN 104 / 113 may communicate with the CN 106 / 115, which may be any type of network configured to provide voice, data, application, and / or Voice over Internet Protocol (VoIP) services to one or more of the WTRUs 102a, 102b, 102c, 102d. The data may have various Quality of Service (QoS) requirements, such as different throughput requirements, delay requirements, error resilience requirements, reliability requirements, data throughput requirements, and mobility requirements. The CN 106 / 115 may provide call control, billing services, mobile location-based services, prepaid calling, Internet connectivity, video distribution, and / or perform high-level security functions, such as user authentication. Although not shown in FIG. 1A, it will be appreciated that the RAN 104 / 113 and / or the CN 106 / 115 may communicate directly or indirectly with other RANs that utilize the same RAT as the RAN 104 / 113 or a different RAT. For example, in addition to being connected to the RAN 104 / 113, which may utilize NR radio technology, the CN 106 / 115 may also communicate with another RAN (not shown) that utilizes GSM, UMTS, CDMA2000, WiMAX, E-UTRA, or WiFi radio technology.

[0029] The CN 106 / 115 may also serve as a gateway for the WTRUs 102a, 102b, 102c, 102d to access the PSTN 108, the Internet 110, and / or other networks 112. The PSTN 108 may include a circuit-switched telephone network providing plain old telephone service (POTS). The Internet 110 may include a global system of interconnected computer networks and devices that use common communications protocols, such as Transmission Control Protocol (TCP), User Datagram Protocol (UDP), and / or Internet Protocol (IP) in the TCP / IP Internet protocol suite. The network 112 may include wired and / or wireless communications networks owned and / or operated by other service providers. For example, the network 112 may include another CN connected to one or more RANs that may utilize the same RAT as the RAN 104 / 113 or a different RAT.

[0030] Some or all of the WTRUs 102a, 102b, 102c, 102d in the communications system 100 may include multi-mode capabilities (e.g., the WTRUs 102a, 102b, 102c, 102d may include multiple transceivers for communicating with different wireless networks over different wireless links). For example, the WTRU 102c shown in FIG. 1A may be configured to communicate with a base station 114a, which may employ a cellular-based wireless technology, and with a base station 114b, which may utilize IEEE 802 wireless technology.

[0031] 1B is a system diagram illustrating an example WTRU 102. As shown in FIG. 1B, the WTRU 102 may include, among other things, a processor 118, a transceiver 120, a transmit / receive element 122, a speaker / microphone 124, a keypad 126, a display / touchpad 128, non-removable memory 130, removable memory 132, a power source 134, a Global Positioning System (GPS) chipset 136, and / or other peripherals 138. It will be understood that the WTRU 102 may include any subcombination of the above elements while remaining consistent with an embodiment.

[0032] 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 in conjunction with a DSP core, a controller, a microcontroller, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) circuit, any other type of integrated circuit (IC), a state machine, etc. The processor 118 may perform signal coding, data processing, power control, input / output processing, and / or any other functionality that enables the WTRU 102 to operate in a wireless environment. The processor 118 may be coupled to the transceiver 120, which may be coupled to the transmit / receive element 122. Although FIG. 1B depicts the processor 118 and the transceiver 120 as separate components, it will be understood that the processor 118 and the transceiver 120 may be integrated together in an electronic package or chip.

[0033] The transmit / receive element 122 may be configured to transmit signals to or receive signals from a base station (e.g., base station 114a) over the air interface 116. For example, in one embodiment, the transmit / receive element 122 may be an antenna configured to transmit and / or receive RF signals. In an embodiment, 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 yet another embodiment, the transmit / receive element 122 may be configured to transmit and / or receive both RF and light signals. It will be appreciated that the transmit / receive element 122 may be configured to transmit and / or receive any combination of wireless signals.

[0034] 1B, the transmit / receive element 122 is depicted as a single element, the WTRU 102 may include any number of transmit / receive elements 122. More specifically, the WTRU 102 may utilize MIMO technology. Thus, in one embodiment, the WTRU 102 may include two or more transmit / receive elements 122 (e.g., multiple antennas) for transmitting and receiving wireless signals over the air interface 116.

[0035] The transceiver 120 may be configured to modulate signals to be transmitted by the transmit / receive element 122 and demodulate signals received by the transmit / receive element 122. As mentioned above, the WTRU 102 may have multi-mode capabilities. Thus, the transceiver 120 may include multiple transceivers to enable the WTRU 102 to communicate via multiple RATs, such as, for example, NR and IEEE 802.11.

[0036] The processor 118 of the WTRU 102 may be coupled to and may receive user input data from a speaker / microphone 124, a keypad 126, and / or a display / touchpad 128 (e.g., a liquid crystal display (LCD) display unit or an organic light emitting diode (OLED) display unit). The processor 118 may output user data to the speaker / microphone 124, the keypad 126, and / or the display / touchpad 128. In addition, the processor 118 may obtain information from and store data in any type of suitable memory, such as a non-removable memory 130 and / or a removable memory 132. The non-removable memory 130 may include a random access memory (RAM), a read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory 132 may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, and the like. In other embodiments, the processor 118 may access information from, and store data in, memory that is not physically located on the WTRU 102, such as located on a server or home computer (not shown).

[0037] The processor 118 may receive power from the power source 134 and may be configured to distribute and / or control power to other components within 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.

[0038] The processor 118 may also be coupled to a GPS chipset 136, which may be configured to provide location information (e.g., longitude and latitude) regarding the current location of the WTRU 102. In addition to or instead of information from the GPS chipset 136, the WTRU 102 may receive location information over the air interface 116 from a base station (e.g., base stations 114a, 114b) and / or may determine its location based on the timing of signals being received from two or more nearby base stations. It will be appreciated that the WTRU 102 may obtain location information using any suitable location determination method while remaining consistent with an embodiment.

[0039] The processor 118 may further be coupled to other peripherals 138, which may include one or more software and / or hardware modules that provide additional features, functionality, and / or wired or wireless connectivity. For example, the peripherals 138 may include an accelerometer, an e-compass, a satellite transceiver, a digital camera (for photos and / or videos), a Universal Serial Bus (USB) port, a vibration device, a television transceiver, a hands-free headset, a Bluetooth module, a frequency modulation (FM) radio unit, a digital music player, a media player, a video game player module, an Internet browser, a virtual reality and / or augmented reality (VR / AR) device, an activity tracker, and the like. The peripherals 138 may include one or more sensors, which may be one or more of a gyroscope, an accelerometer, a Hall effect sensor, a magnetometer, an orientation sensor, a proximity sensor, a temperature sensor, a time sensor, a geolocation sensor, an altimeter, a light sensor, a touch sensor, a magnetometer, a barometer, a gesture sensor, a biometric sensor, and / or a humidity sensor.

[0040] The WTRU 102 may include a full-duplex radio where transmission and reception of some or all of the signals associated with a particular subframe (e.g., for both the UL (e.g., for transmission) and the downlink (e.g., for reception)) may be parallel and / or simultaneous. The full-duplex radio may include an interference management unit 139 to reduce and / or substantially eliminate self-interference via hardware (e.g., a choke) or via signal processing via a processor (e.g., a separate processor (not shown) or processor 118). In an embodiment, the WTRU 102 may include a half-duplex radio for transmission and reception of some or all of the signals (e.g., associated with a particular subframe for either the UL (e.g., for transmission) or the downlink (e.g., for reception).

[0041] 1C is a system diagram illustrating the RAN 104 and the CN 106. As mentioned above, the RAN 104 may employ E-UTRA radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 104 may also communicate with the CN 106.

[0042] The RAN 104 may include eNodeBs 160a, 160b, 160c, although it will be understood that the RAN 104 may include any number of eNodeBs while remaining consistent with an embodiment. The eNodeBs 160a, 160b, 160c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the eNodeBs 160a, 160b, 160c may implement MIMO technology. Thus, the eNodeB 160a, for example, may use multiple antennas to transmit wireless signals to and / or receive wireless signals from the WTRU 102a.

[0043] Each of the eNodeBs 160a, 160b, 160c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, and scheduling of users in the UL and / or DL, etc. As shown in FIG 1C, the eNodeBs 160a, 160b, 160c may communicate with each other over an X2 interface.

[0044] 1C may include a Mobility Management Entity (MME) 162, a Serving Gateway (SGW) 164, and a Packet Data Network (PDN) Gateway (or PGW) 166. Although each of the above elements is depicted as part of the CN 106, it will be understood that any of these elements may be owned and / or operated by an entity different from the CN operator.

[0045] The MME 162 may be connected to each of the eNodeBs 160a, 160b, 160c in the RAN 104 via an S1 interface and may act as a control node. For example, the MME 162 may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, bearer activation / deactivation, selecting a particular serving gateway during initial attach of the WTRUs 102a, 102b, 102c, etc. The MME 162 may provide a control plane function for switching between the RAN 104 and other RANs (not shown) that employ other radio technologies, such as GSM and / or WCDMA.

[0046] The SGW 164 may be connected to each of the eNodeBs 160a, 160b, 160c in the RAN 104 via an S1 interface. The SGW 164 may generally route and forward user data packets to / from the WTRUs 102a, 102b, 102c. The SGW 164 may perform other functions, such as anchoring the user plane during inter-eNodeB handover, triggering paging when DL data is available to the WTRUs 102a, 102b, 102c, as well as managing and storing the context of the WTRUs 102a, 102b, 102c.

[0047] The SGW 164 may be connected to a PGW 166, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices.

[0048] The CN 106 may facilitate communications with other networks. For example, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, 102c and traditional fixed-line communications devices. For example, the CN 106 may include or communicate with an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that serves as an interface between the CN 106 and the PSTN 108. In addition, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to other networks 112, which may include other wired and / or wireless networks owned and / or operated by other service providers.

[0049] Although in Figures 1A-8D, the WTRU is described as a wireless terminal, it is contemplated that in certain representative embodiments, such a terminal may use a wired communications interface (e.g., temporarily or permanently) with the communications network.

[0050] In an exemplary embodiment, the other network 112 may be a WLAN.

[0051] A WLAN in infrastructure basic service set (BSS) mode may have an access point (AP) for the BSS and one or more stations (STAs) associated with the AP. The AP may have access or interface to a distribution system (DS) or another type of wired / wireless network that carries traffic within and / or outside the BSS. Traffic to a STA originating from outside the BSS may arrive through the AP and be delivered to the STA. Traffic originating from a STA to a destination outside the BSS may be sent to the AP for delivery to the respective destination. Traffic between STAs in the BSS may be sent through the AP, e.g., a source STA may send traffic to the AP and the AP may deliver the traffic to the destination STA. Traffic between STAs in the BSS may be considered and / or referred to as peer-to-peer traffic. Peer-to-peer traffic may be sent (e.g., directly) between a source STA and a destination STA using a direct link setup (DLS). In one representative embodiment, the DLS may use 802.11e DLS or 802.11z Tunneled DLS (TDLS). A WLAN using an Independent BSS (IBSS) mode may not have an AP, and STAs (e.g., all of the STAs) within or using an IBSS may communicate directly with each other. IBSS mode communication may sometimes be referred to herein as "ad-hoc" mode communication.

[0052] When using 802.11ac infrastructure mode of operation or a similar mode of operation, the AP may transmit beacons on a fixed channel, such as a primary channel. The primary channel may be a fixed width (e.g., 20 MHz wide bandwidth) or a width dynamically set via signaling. The primary channel may be the operating channel of the BSS and may be used by STAs to establish a connection with the AP. In one representative embodiment, for example, in an 802.11 system, carrier sense multiple access / collision avoidance (CSMA / CA) may be implemented. With CSMA / CA, STAs (e.g., every STA), including the AP, may sense the primary channel. If the primary channel is sensed / detected and / or determined to be busy by a particular STA, the particular STA may back off. Within a given BSS, one STA (e.g., only one station) may transmit at any given time.

[0053] A high throughput (HT) STA may use a 40 megahertz wide channel for communication, for example, via combining a primary 20 megahertz channel with an adjacent or non-adjacent 20 megahertz channel to form a 40 megahertz wide channel.

[0054] A Very High Throughput (VHT) STA may support channels that are 20 megahertz, 40 megahertz, 80 megahertz, and / or 160 megahertz wide. The 40 megahertz and / or 80 megahertz channels may be formed by combining consecutive 20 megahertz channels. The 160 megahertz channel may be formed by combining eight consecutive 20 megahertz channels or by combining two non-contiguous 80 megahertz channels, which may be referred to as an 80+80 configuration. For the 80+80 configuration, the data may be passed through a segment parser after channel encoding that may split the data into two streams. Inverse Fast Fourier Transform (IFFT) processing and time domain processing may be performed separately for each stream. The streams may be mapped onto the two 80 megahertz channels, and the data may be transmitted by the transmitting STA. At the receiver of the receiving STA, the operations described above for the 80+80 configuration may be reversed and the combined data may be sent to a media access control (MAC).

[0055] Sub-gigahertz mode operation is supported by 802.11af and 802.11ah. The channel operating bandwidth and carriers are reduced in 802.11af and 802.11ah compared to those used in 802.11n and 802.11ac. 802.11af supports 5, 10, and 20 megahertz bandwidths in TV White Space (TVWS) spectrum, and 802.11ah supports 1, 2, 4, 8, and 16 megahertz bandwidths using non-TVWS spectrum. According to an embodiment, 802.11ah may support meter-type control / machine-type communication, such as MTC devices in macro coverage areas. MTC devices may have limited functionality, including, for example, support of (e.g., only) certain bandwidths and / or limited bandwidths. The MTC device may include a battery that has a battery life above a threshold (eg, to maintain a very long battery life).

[0056] WLAN systems that can support multiple channels and channel bandwidths, such as 802.11n, 802.11ac, 802.11af, and 802.11ah, include a channel that may be designated as a primary channel. The primary channel may have a bandwidth equal to the largest common operating bandwidth supported by all STAs in the BSS. The bandwidth of the primary channel may be set and / or limited by the STA that supports the smallest bandwidth operating mode among all STAs operating in the BSS. In the 802.11ah example, for STAs (e.g., MTC type devices) that support (e.g., only) 1 megahertz mode, the primary channel may be 1 megahertz wide, even if the AP and other STAs in the BSS support 2 megahertz, 4 megahertz, 8 megahertz, 16 megahertz, and / or other channel bandwidth operating modes. Carrier sensing and / or network allocation vector (NAV) setting may depend on the status of the primary channel. For example, if the primary channel is busy because a STA (that only supports a 1 MHz mode of operation) is transmitting to the AP, the entire available frequency band may be considered busy even though most of the frequency band may remain idle and available for use.

[0057] In the United States, the available frequency bands that may be used by 802.11ah are 902 MHz to 928 MHz. In South Korea, the available frequency bands are 917.5 MHz to 923.5 MHz. In Japan, the available frequency bands are 916.5 MHz to 927.5 MHz. The total bandwidth available for 802.11ah is 6 MHz to 26 MHz, depending on country regulations.

[0058] 1D is a system diagram illustrating an example RAN 113 and CN 115. As described above, the RAN 113 may communicate with the WTRUs 102a, 102b, 102c over the air interface 116 utilizing NR radio technology. The RAN 113 may also communicate with the CN 115.

[0059] The RAN 113 may include gNBs 180a, 180b, 180c, although it will be understood that the RAN 113 may include any number of gNBs while remaining consistent with an embodiment. The gNBs 180a, 180b, 180c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the gNBs 180a, 180b, 180c may implement MIMO technology. For example, the gNBs 180a, 108b may utilize beamforming to transmit signals to and / or receive signals from the gNBs 180a, 180b, 180c. Thus, the gNB 180a may transmit wireless signals to and / or receive wireless signals from the WTRU 102a using, for example, multiple antennas. In an embodiment, the gNBs 180a, 180b, 180c may implement carrier aggregation techniques. For example, the gNB 180a may transmit multiple component carriers to the WTRU 102a (not shown). A subset of these component carriers may be on an unlicensed spectrum, while the remaining component carriers may be on a licensed spectrum. In an embodiment, the gNBs 180a, 180b, 180c may implement coordinated multipoint (CoMP) techniques. For example, the WTRU 102a may receive coordinated transmissions from the gNBs 180a and 180b (and / or gNB 180c).

[0060] The WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using transmissions associated with a scalable numerology. For example, the OFDM symbol spacing and / or OFDM subcarrier spacing may vary for different transmissions, different cells, and / or different portions of the wireless transmission spectrum. The WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using subframes or transmission time intervals (TTIs) of different or scalable lengths (e.g., including different numbers of OFDM symbols and / or lasting for different lengths of absolute time).

[0061] The gNBs 180a, 180b, 180c may be configured to communicate with the WTRUs 102a, 102b, 102c in a standalone configuration and / or a non-standalone configuration. In a standalone configuration, the WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c without accessing another RAN (e.g., eNodeBs 160a, 160b, 160c). In a standalone configuration, the WTRUs 102a, 102b, 102c may utilize one or more of the gNBs 180a, 180b, 180c as mobility anchor points. In a standalone configuration, the WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using signals in unlicensed bands. In a non-standalone configuration, the WTRUs 102a, 102b, 102c may communicate / connect to a gNB 180a, 180b, 180c while also communicating / connecting to another RAN, such as an eNodeB 160a, 160b, 160c. For example, the WTRUs 102a, 102b, 102c may implement the DC principle to communicate with one or more gNBs 180a, 180b, 180c and one or more eNodeBs 160a, 160b, 160c substantially simultaneously. In a non-standalone configuration, the eNodeBs 160a, 160b, 160c may act as mobility anchors for the WTRUs 102a, 102b, 102c, and the gNBs 180a, 180b, 180c may provide additional coverage and / or throughput for serving the WTRUs 102a, 102b, 102c.

[0062] Each of the gNBs 180a, 180b, 180c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in the UL and / or DL, support for network slicing, dual connectivity, interworking between NR and E-UTRA, routing of user plane data to User Plane Functions (UPFs) 184a, 184b, and routing of control plane information to Access and Mobility Management Functions (AMFs) 182a, 182b, etc. As shown in FIG. 1D, the gNBs 180a, 180b, 180c may communicate with each other over the Xn interface.

[0063] 1D may include at least one AMF 182a, 182b, at least one UPF 184a, 184b, at least one Session Management Function (SMF) 183a, 183b, and possibly a Data Network (DN) 185a, 185b. Although each of the above elements is depicted as part of the CN 115, it will be understood that any of these elements may be owned and / or operated by an entity different from the CN operator.

[0064] The AMF 182a, 182b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 113 via an N2 interface and may act as a control node. For example, the AMF 182a, 182b may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, supporting network slicing (e.g., handling different PDU sessions with different requirements), selecting a particular SMF 183a, 183b, managing registration areas, terminating NAS signaling, and mobility management, etc. Network slicing may be used by the AMF 182a, 182b to customize CN support for the WTRUs 102a, 102b, 102c based on the type of service utilized by the WTRUs 102a, 102b, 102c. Different network slices may be established for different use cases, such as, for example, services relying on ultra-reliable low latency (URLLC) access, services relying on eMBB access, and / or services for machine type communications (MTC) access, etc. The AMF 162 may provide a control plane function for switching between the RAN 113 and other RANs (not shown) that employ other radio technologies, such as LTE, LTE-A, LTE-A Pro, and / or non-3GPP access technologies such as WiFi.

[0065] The SMFs 183a, 183b may be connected to the AMFs 182a, 182b in the CN 115 via an N11 interface. The SMFs 183a, 183b may also be connected to the UPFs 184a, 184b in the CN 115 via an N4 interface. The SMFs 183a, 183b may select and control the UPFs 184a, 184b and configure the routing of traffic through the UPFs 184a, 184b. The SMFs 183a, 183b may perform other functions such as managing and assigning UE IP addresses, managing PDU sessions, controlling policy enforcement and QoS, and providing downlink data notification. The PDU session types may be IP-based, non-IP-based, Ethernet-based, etc.

[0066] The UPFs 184a, 184b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 113 via an N3 interface, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices. The UPFs 184a, 184b may perform other functions, such as routing and forwarding packets, enforcing user plane policies, supporting multi-homing PDU sessions, handling user plane QoS, buffering downlink packets, and providing mobility anchoring.

[0067] The CN 115 may facilitate communication with other networks. For example, the CN 115 may include or communicate with an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that serves as an interface between the CN 115 and the PSTN 108. In addition, the CN 115 may provide the WTRUs 102a, 102b, 102c with access to other networks 112, which may include other wired and / or wireless networks owned and / or operated by other service providers. In an embodiment, the WTRUs 102a, 102b, 102c may be connected to local data networks (DNs) 185a, 185b through the UPFs 184a, 184b via an N3 interface to the UPFs 184a, 184b and an N6 interface between the UPFs 184a, 184b and the DNs 185a, 185b.

[0068] 1A-1D and the corresponding description thereof, one or more or all of the functions described herein with respect to one or more of the WTRUs 102a-d, base stations 114a-b, eNodeBs 160a-c, MME 162, SGW 164, PGW 166, gNBs 180a-c, AMFs 182a-b, UPFs 184a-b, SMFs 183a-b, DNs 185a-b, and / or any other devices described herein may be performed by one or more emulation devices (not shown). The emulation devices may be one or more devices configured to emulate one or more or all of the functions described herein. For example, the emulation devices may be used to test other devices and / or to simulate network and / or WTRU functions.

[0069] The emulation device may be designed to perform one or more tests of other devices in a laboratory environment and / or in an operator network environment. For example, the one or more emulation devices may perform one or more or all functions while fully or partially implemented and / or deployed as part of a wired and / or wireless communication network to test other devices in the communication network. The one or more emulation devices may perform one or more or all functions while temporarily implemented / deployed as part of a wired and / or wireless communication network. The emulation device may be directly coupled to another device for testing purposes and / or may perform the tests using over-the-air wireless communication.

[0070] The emulation device or devices may perform one or more functions, including all functions, without being implemented / deployed as part of a wired and / or wireless communication network. For example, the emulation device may be utilized in a test lab and / or in a test scenario in a non-deployed (e.g., test) wired and / or wireless communication network to perform tests of one or more components. The emulation device or devices may be test equipment. Direct RF coupling and / or wireless communication via RF circuitry (which may include, for example, one or more antennas) may be used by the emulation device to transmit and / or receive data.

[0071] Hybrid Automatic Repeat Request (HARQ) operation at the WTRU may be modified, for example, due to larger RTD times for non-terrestrial networks. For example, the soft buffer size at the WTRU may be increased for large RTD times. For example, the HARQ procedure may be modified to handle high RTD cases.

[0072] For example, a non-terrestrial network (NTN) may be utilized to provide 5G services in unserved areas that may not be covered by a terrestrial 5G network. The unserved areas may include, for example, isolated remote areas, rural areas, offshore, etc. The NTN may be used to improve the performance of the terrestrial network in the unserved areas (e.g., in a cost-effective manner). The NTN may be used to enhance the reliability of 5G services, for example, by providing availability and scalability for 5G deployment.

[0073] The term "network" may refer to one or more gNBs, which may be associated with one or more transmission / reception points (TRPs) and / or any other nodes in a radio access network (RAN).

[0074] For example, as illustrated in the embodiments shown in Figures 2-4, various NTN architectures may be based on a separation of RAN functions between a ground unit and a satellite.

[0075] FIG. 2 illustrates an example of a next-generation radio access network (NG-RAN) architecture in a non-terrestrial network with a bent-pipe payload. In an example, the NG-RAN may include a radio access network connected to a 5G core network (CN). For example, a WTRU (e.g., as shown in FIG. 2) may communicate with a data network via the NG-RAN (e.g., including a transponder such as an RF bent-pipe transponder, an NTN remote radio unit (RRU), and a gNB coupled to the 5G CN (e.g., via an N1 / 2 / 3 interface).

[0076] FIG. 3 illustrates an example of an NG-RAN architecture in a non-terrestrial network with a gNB distributed unit (gNB-DU) processed payload. As illustrated in the example in FIG. 3, the gnB-DU may be connected to the gnB-CU via an F1 interface, for example, using a satellite radio interface (SRI). For example, a WTRU (e.g., as illustrated in FIG. 3) may communicate with a data network via an NG-RAN (e.g., including a gNB-DU, an NTN RRU, and a gNB-CU coupled to a 5G CN (e.g., via an N1 / 2 / 3 interface).

[0077] Figure 4 shows an example of an NG-RAN architecture in a non-terrestrial network with gNB processed payload. As shown in the example in Figure 4, the gNB may be connected to the 5G CN via an N1 / 2 / 3 interface (e.g., through an SRI). For example, a WTRU (e.g., shown in Figure 4) may communicate with a data network via an NG-RAN (e.g., including a gNB and an NTN RRU coupled to a 5G CN (e.g., via an N1 / 2 / 3 interface).

[0078] The WTRU may be configured (e.g., in NR) to utilize one or more hybrid automatic repeat request (HARQ) protocols, for example, to achieve robustness against transmission errors. For example, robustness can be achieved by (e.g., by enabling) soft combining and fast retransmission. Hybrid ARQ may utilize multiple stop and wait protocols to enable continuous transmission of data. The WTRU MAC may include a HARQ entity for (e.g., each) serving cell. The WTRU may maintain several parallel HARQ processes. (e.g., each) HARQ process may be associated with a HARQ process identifier. (e.g., each) HARQ process may be associated with a HARQ buffer. Asynchronous HARQ protocols may be utilized in the downlink and uplink directions. A HARQ process identifier associated with a downlink or uplink transmission may be signaled (e.g., explicitly signaled), for example, as part of downlink control information (DCI).

[0079] The round trip delay (RTD) for communication in a non-terrestrial network may be much higher than the RTD for communication in a terrestrial network. For example, the RTD for a low earth orbit (LEO) satellite at an altitude of about 600 kilometers may be as low as 28 milliseconds. The RTD for a medium earth orbit (MEO) satellite at an altitude of about 10,000 kilometers may be as low as 190 milliseconds. The RTD for a geosynchronous earth orbit (GEO) satellite may be as high as 545 milliseconds. A large RTD time may have a direct impact on the number of HARQ processes that the WTRU can sustain to support high data rate services. For example, the soft buffer size in the WTRU may increase with the number of HARQ processes.

[0080] In an embodiment, the HARQ function may be disabled for non-terrestrial communications. The WTRU (e.g., with HARQ disabled) may rely on higher layer transmissions. However, disabling the HARQ function may lead to reduced reliability or increased latency to achieve the desired reliability. For example, voice services using radio link monitoring-unacknowledged mode (RLM-UM) may suffer from a lack of reliability, for example, if HARQ is disabled. Services with less frequent data transfers may benefit from HARQ operation and may not be constrained by large propagation delays for NTN communications.

[0081] The WTRU may transmit a radio resource control (RRC) message, for example, on signaling radio bearer 0 (SRB0). The RRC message may be transmitted, for example, before receiving a full RRC configuration or before the establishment of signaling radio bearer 1 (SRB1). In an embodiment, the WTRU may transmit MSG3 (e.g., an RRC Setup Request message), for example, using a radio link control (RLC) transparent mode (e.g., during initial access). The WTRU may receive MSG4 (e.g., an RRC Setup message) from the network, for example, to establish SRB1. HARQ may be utilized, for example, during (e.g., legacy) MSG3 and / or MSG4 transmissions, for example, to ensure reliability of communication. Reliability of the initial signaling exchange may be degraded, for example, if HARQ is disabled. One or more RRC procedures may involve the transmission of a (e.g., single) RLC protocol data unit (PDU). Using RLC level status reporting to recover lost PDUs (eg, without HARQ) may add significant latency to the RRC procedure.

[0082] Systems and methods for providing open-loop HARQ are described herein. A WTRU may apply (e.g., be configured to apply) a first set of HARQ capabilities and / or a first HARQ behavior for a first set of HARQ processes and a second behavior for a second set of HARQ processes. The HARQ configurations may be for downlink HARQ processes, uplink processes, or both downlink and uplink processes.

[0083] In an embodiment, the HARQ behavior may be modeled and / or configured as a type of HARQ processing. The type of HARQ processing and / or behavior for the HARQ processing may include, for example, one or more of closed-loop HARQ processing, open-loop HARQ processing, and / or stateless HARQ processing. For example, for closed-loop HARQ processing, soft-combining of various transmissions may be applicable. For example, for closed-loop HARQ processing, transmission and / or reception of HARQ feedback (e.g., HARQ ACK / NACK) may be applicable. For example, for open-loop HARQ processing, soft-combining of various transmissions may be applicable. For example, for open-loop HARQ processing, transmission / reception of HARQ feedback may not be applicable. For example, for stateless HARQ processing, soft-combining and transmission / reception of HARQ feedback may not be applicable.

[0084] The WTRU may determine the type of HARQ process that can be associated with a given HARQ process, e.g., based on semi-static configuration and / or dynamic signaling. In an embodiment, the WTRU may apply a pre-configured HARQ process type (HPT) to (e.g., each) transmission and / or reception, e.g., for the duration of an RRC connection or for the duration of an RRC configuration. In an embodiment (e.g., an embodiment using semi-static configuration), the WTRU may apply a pre-configured HARQ process type specific to the serving cell. For example, the type of HARQ process and / or HARQ process to be applied may be indicated (e.g., in system information) and / or may be implicitly determined (e.g., depending on the serving frequency and / or cell identifier).

[0085] Dynamic methods (e.g., used to determine the HARQ process type) may include one or more of the following: In an embodiment of a dynamic method, the WTRU may apply a particular HARQ process type to a subset of the configured HARQ process(es). The WTRU may assume open-loop HARQ operation for one or more predefined HARQ process identifiers (e.g., HARQ process ID (PID) 0, etc.). The WTRU may be configured (e.g., explicitly configured) with a list of HARQ process identifiers (IDs), for which the open-loop HARQ process type may be applied. The configuration may be provided, for example, via an RRC message.

[0086] In an embodiment of the dynamic method, the WTRU may apply a preconfigured type of HARQ process to a particular transmission (e.g., a downlink transmission, an uplink transmission, or both downlink and uplink transmissions). For example, the type of HARQ process applied may be based on a dynamic indication in the downlink control information (DCI) or the assignment and / or grant information (e.g., dynamic or configured). The WTRU may determine the type of HARQ process based, for example, on the type of DCI received for the transmission. For example, the WTRU may apply a first HARQ process if the WTRU receives a first DCI type or format and may apply a second HARQ process otherwise (e.g., if the WTRU receives a second DCI type or format).

[0087] In dynamic method embodiments, the WTRU may apply a pre-configured type of HARQ process to a particular transmission (e.g., downlink transmission, uplink transmission, or both downlink and uplink transmissions). For example, the type of HARQ process applied may be based on the type of scheduling information. In embodiments, the WTRU may apply a first process to HARQ processes associated with semi-statically configured assignments and / or grants and may apply a second process to dynamically scheduled transmissions. For example, the WTRU may apply the first process to HARQ processes associated with semi-statically configured assignments of a first type (e.g., semi-persistent scheduling (SPS) type 0) and may apply the second process otherwise.

[0088] In an embodiment, the WTRU may determine the type of HARQ process to be applied for a transmission based on, for example, a HARQ process identifier that may be included in an UL grant. In (e.g., additional or alternative) embodiments, the WTRU may determine the type of HARQ process to apply (e.g., for a reception) based on, for example, a HARQ process identifier that may be included in downlink control information (DCI) carrying a downlink (DL) assignment.

[0089] In an embodiment, the WTRU may apply (e.g., be configured to apply) a first HARQ process for a HARQ process scheduled for HARQ PID=x, where x may be, for example, zero (PID=0), which may represent a closed-loop HARQ process. The WTRU may otherwise apply (e.g., be configured to apply) a second process (e.g., an open-loop HARQ process). The WTRU MAC layer may instruct the PHY layer to generate HARQ feedback for (e.g., only) DL transmissions for HARQ PID=x. The WTRU MAC layer may assume (e.g., implicitly assume) a HARQ ACK for UL transmissions other than for the HARQ PIDs (e.g., based on the HARQ feedback for HARQ PID=x), so that, for example, the HARQ process can be suspended after a transmission and / or the HARQ buffer can be cleared. The WTRU may, for example, use a different (e.g., legacy) procedure (e.g., NR R15 HARQ procedure, LTE R8 HARQ procedure, etc.) to process HARQ feedback for other PID values. The WTRU may, for example, be configured such that a UL HARQ process (e.g., configured for open-loop HARQ process or stateless HARQ process) cannot reach a maximum number of HARQ retransmissions and / or trigger a radio link failure (RLF). The WTRU may, for example, be configured not to count and / or not to update a HARQ retransmission counter. For example, the WTRU may toggle (e.g., be configured to toggle) a New Data Indicator (NDI) for a HARQ process that corresponds to a HARQ PID configured for a stateless HARQ process (e.g., HARQ PID!=0 in the previous example). The WTRU may (e.g., otherwise) perform a different (e.g., legacy) decision for toggling NDI (e.g., NR R15 procedure for toggling NDI, LTE R8 procedure for toggling NDI, etc.).

[0090] The WTRU may transmit (or be configured to transmit) an indication of long term HARQ performance to a network entity, e.g., in the absence of HARQ feedback. The indication may be utilized by the network entity to, e.g., adjust the number of blind transmissions. The indication may be communicated, e.g., via an RLC status report. The long term HARQ performance may be triggered, e.g., based on the number of cyclic redundancy check (CRC) failures in a time period. The RLC status report may be triggered, e.g., based on the number of CRC failures in a time period. The triggered RLC status report may or may not include the long term HARQ feedback.

[0091] The WTRU may be configured with discontinuous reception (DRX). The DRX behavior may be based on (e.g., dependent on) the HARQ process. In an embodiment, the WTRU may handle (e.g., be configured to handle) one or more timers associated with DRX based on, for example, the HARQ process type associated with the DL assignment and / or UL grant.

[0092] The WTRU may perform various actions (e.g., as described herein) if (when) DRX is configured. The MAC entity of the WTRU (e.g., in Active Time state) may, for example, monitor the PDCCH to determine whether the physical downlink control channel indicates a UL or DL ​​transmission. The WTRU may determine whether the corresponding HARQ processing type is open loop or closed loop.

[0093] The WTRU may, for example, start a drx-HARQ-RTT-TimerDL timer for a corresponding HARQ process in the first symbol (e.g., for a DL transmission indicated by the PDCCH with the corresponding closed-loop HARQ process type) (e.g., after the end of the corresponding transmission carrying DL HARQ feedback) and may stop a drx-RetransmissionTimerDL timer for the corresponding HARQ process. The WTRU may, for example, start or restart a drx-RetransmissionTimerDL timer for a corresponding HARQ process (e.g., for a DL transmission indicated by the PDCCH with the corresponding open-loop HARQ process type).

[0094] The WTRU may, for example, start a drx-HARQ-RTT-TimerUL timer for a corresponding HARQ process in the first symbol (e.g., for an UL transmission indicated by the PDCCH with the corresponding closed-loop HARQ process type) (e.g., after the end of the first repetition of the corresponding PUSCH transmission) and may stop a drx-RetransmissionTimerUL timer for the corresponding HARQ process. The WTRU may, for example, start or restart a drx-RetransmissionTimerUL timer for a corresponding HARQ process (e.g., for an UL transmission indicated by the PDCCH and the corresponding open-loop HARQ process type).

[0095] The WTRU may perform (e.g., be configured to perform) DRX adaptation, e.g., to account for or account for propagation delay. DRX adaptation may be performed by the WTRU (e.g., autonomously) and / or based on configurations and / or commands received from a network entity. In an embodiment, DRX may be utilized to save power at the WTRU, e.g., based on (e.g., in response to) data transmission / reception behavior. Non-terrestrial networks may experience large propagation delays (e.g., 95 ms for LEO and 272 ms for GEO). The WTRU may not monitor (e.g., is not required to monitor) the PDCCH, e.g., when it was not in an active time (e.g., while in an inactive time). The active time may include a time when one or more of the following timers are running: drx-onDurationTimer, drx-InactivityTimer, drx-RetransmissionTimerDL, drx-RetransmissionTimerUL, or ra-ContentionResolutionTimer. In an embodiment, the active time may include, for example, the time when a scheduling request is pending. If the WTRU is in active time while waiting for a response from the network due to significant propagation delays such as NTN, unnecessary power consumption may occur.

[0096] The WTRU may apply (e.g., be configured to apply) discontinuous reception (DRX), for example, based on a propagation delay. Applying DRX may be used to attempt to maximize sleep time without significantly adversely affecting performance (e.g., latency, reliability, etc.). In an example, if there are no other DL receptions and / or other UL transmissions predicted before the predicted response to the UL transmission, the WTRU may enter a sleep mode for a preconfigured duration upon completion of the UL transmission for which a response is predicted. In an example, the WTRU may sleep (e.g., be configured to sleep) while waiting for a response from the network (e.g., instead of continuously monitoring the PDCCH). In (additional and / or alternative) examples, the WTRU may apply DRX based on a propagation delay for UL transmissions, including, but not limited to, transmissions of a preamble, transmissions of an MSG3, transmissions of a scheduling request, etc. In an example, the WTRU may start (e.g., be configured to start) a timer (e.g., a propagation delay timer) upon a UL transmission. In an embodiment, the WTRU may not monitor (e.g., not be required to monitor) the PDCCH if, for example, the propagation delay timer is running. In an embodiment, the WTRU may not monitor (e.g., not be required to monitor) the PDCCH if, for example, the propagation delay timer is running and one or more of the following timers are not running: drx-onDurationTimer, drx-InactivityTimer, drx-RetransmissionTimerDL, or drx-RetransmissionTimerUL. In an embodiment, the WTRU may not monitor (e.g., not be required to monitor) the PDCCH if the propagation delay timer is running and the ra-ContentionResolutionTimer is running. In an embodiment, the WTRU may not monitor (e.g., not be required to monitor) the PDCCH if the propagation delay timer is running and a response to a scheduling request is pending.The WTRU may wake up and monitor (eg, be configured to wake up and monitor) the PDCCH, for example, when a propagation delay timer expires.

[0097] FIG. 5 illustrates an embodiment associated with logical channel restriction / logical channel prioritization.

[0098] Systems and methods are described herein that provide logical channel prioritization and / or logical channel multiplexing, which may be based on a HARQ process (e.g., HARQ process type or HARQ process ID). The WTRU may select (e.g., be configured to select) a logical channel(s) for UL transmission based, for example, on HARQ characteristics associated with the UL grant. For example, FIG. 5 shows an UL grant that identifies a HARQ process ID "x" associated with an open-loop HARQ process type shown under "HARQ process config." In an embodiment, one or more of logical channels 2...n may be selected for UL transmission (e.g., LCH 1 is restricted from use because it is a closed-loop type logical channel shown in "logical channel config").

[0099] The WTRU may be configured with applicable HARQ characteristics associated with logical channels. The HARQ characteristics may correspond to applicable process ID(s) and / or applicable HARQ process type (e.g., open loop or closed loop). In an embodiment, one or more UL grants may provide different reliability values ​​or different latency values ​​to achieve a given reliability level. One or more UL transmissions (e.g., UL transmission(s) with priority above a threshold that are in a category indicated as having a higher priority than other category(s)) may be mapped to an UL grant that provides better reliability. For example, a logical channel (LCH) associated with a signaling radio bearer may be mapped to an UL grant with enabled HARQ feedback. The mapping may be an indication of association, which may be received (e.g., via signaling), pre-configured, etc. The mapping restriction may be an indication of a selection (e.g., a selection of channel(s) permitted for use, a selection of channel(s) not permitted for use, etc.), and the indication may be received (e.g., via a signal), may be pre-configured, etc.

[0100] The WTRU may be configured with LCH mapping restrictions associated with the type of HARQ process (e.g., as shown in FIG. 5, LCH 1 is restricted from use based on the HARQ process ID and its associated HARQ process type indicated in the UL grant, and LCH 2...n are allowed to use based on the HARQ process ID and its associated HARQ process type indicated in the UL grant). For example, data available for transmission for a first set of LCH(s) may be multiplexed into transport blocks corresponding to the HARQ process(es) of the first type of HARQ process, and data available for transmission for a second set of LCH(s) may be multiplexed based on the second set of HARQ process(es) of the second type of HARQ process.

[0101] The WTRU may perform logical channel prioritization (LCP), e.g., based on (e.g., (pre)configured) mapping restrictions between logical channels and HARQ process type(s) allowed for the logical channels (e.g., the mapping restrictions are selections of logical channel(s) associated with the allowed HARQ process type(s)). For example, the WTRU may perform LCP based on (e.g., (pre)configured) mapping restrictions between logical channels and HARQ process ID(s) allowed for the logical channels (e.g., as shown in FIG. 5 , LCH 1 is restricted from use for transmissions based on LCH 1 associated with closed-loop HARQ process types that are not allowed, e.g., not associated with the indicated HARQ process ID, and / or LCH 2 and LCH n are allowed from use for transmissions based on LCH 2 and LCH n associated with allowed open-loop HARQ process types). The WTRU may transmit UL MAC SDUs from a logical channel using an UL grant that includes the HARQ process ID(s) and / or applicable HARQ process type configured for the logical channel (e.g., the allowed LCH(s) resulting from the mapping restriction). The WTRU may skip a logical channel, e.g., if its configured HARQ characteristics do not match the HARQ characteristics of the UL grant (e.g., as shown in FIG. 5, LCH 1 is skipped, e.g., restricted in use, based on a HARQ process type that does not match the HARQ process type associated with the HARQ process ID indicated in the UL grant). The WTRU may, e.g., apply a lower priority to a logical channel whose HARQ characteristics do not match the HARQ characteristics of the UL grant compared to a priority for a logical channel whose HARQ characteristics match the HARQ characteristics of the UL grant. The WTRU may assume (e.g., based on a configuration), e.g., if a logical channel is not configured with applicable HARQ characteristics, the logical channel can be mapped to any UL grant regardless of the applicable HARQ characteristics.

[0102] The WTRU may be configured with a service request (SR) configuration for an LCH (e.g., common to LCH) configured with a mapping restriction that can correspond to a (e.g., common) type of HARQ process. In an embodiment, the WTRU may perform an SR transmission using a first set of resources (e.g., on a physical uplink control channel (PUCCH) or on a physical random access channel (PRACH)) if, for example, new data becomes available for transmission for the LCH with a mapping restriction to a first type of HARQ process. The WTRU may perform an SR transmission using a second set of resources, for example, otherwise.

[0103] The WTRU may perform LCP, for example, by considering the time the data is stored in the buffer. In an embodiment, the WTRU may perform LCP based on the age (ΔT) of the data in the logical channel. The age of the data may measure the time the data is stored in the buffer. The age of the data may be determined, for example, based on the arrival time of the data to the buffer. The WTRU may consider ΔT of (e.g., each) logical channel, for example, when the WTRU selects a logical channel that fills the configured resources. In an embodiment, the WTRU may perform LCP, for example, by selecting a logical channel based on the time the data was stored in the buffer and the priority of the data (e.g., in combination with the token bucket Bj value for the logical channel). For example, a function f(ΔT, priority) may be defined and used to select the logical channel. The function f(ΔT, priority) may be calculated, for example, based on the value of ΔT and the priority of the logical channel. The function f(ΔT, priority) may depend on the Bj value for the logical channel (e.g., the latest number of tokens available in a token bucket scheme). In an embodiment associated with function f, the WTRU may be configured to select the logical channel that belongs to the highest priority. Among those selected logical channels, the WTRU may be configured to service the logical channels based on descending order of ΔT. For example, the process may continue to the next priority until the logical channel (e.g., all logical channels) is served or the UL resources in the grant (e.g., all UL resources) are exhausted, whichever is earlier. In an embodiment associated with function f, the WTRU may be configured to select the logical channel(s) whose ΔT value is above a threshold. Among those selected logical channels, the WTRU may be configured to service the logical channels based on their priority level (e.g., from highest to lowest). The process may continue first in descending order of ΔT, then in decreasing priority.This may continue until the logical channel (eg, all logical channels) are served or the UL resources in the grant (eg, all UL resources) are exhausted, whichever occurs first.

[0104] For example, MAC control element (MAC CE) multiplexing may be performed depending on the HARQ process. The WTRU may select (e.g., be configured to select) one or more MAC CE(s) for transmission based on, for example, the HARQ characteristics associated with the UL grant. The WTRU may multiplex (configure to multiplex) a MAC PDU to a MAC CE, for example, if the HARQ characteristics associated with the UL grant match the (e.g., pre-configured) HARQ characteristics for the MAC CE. The HARQ characteristics may correspond to the applicable process ID(s) and / or the applicable HARQ process type(s). In an embodiment, (e.g., each) MAC CE may be configured with (e.g., a single) applicable HARQ characteristic. In (e.g., additional and / or alternative) embodiments, HARQ characteristics may be configured per MAC CE type. For example, if multiple UL grants provide different reliability or different latency to achieve a given reliability, the MAC CE(s) (e.g., critical MAC CE(s)) may be mapped to the UL grant that provides better reliability. In an embodiment, a failure in a MAC CE transmission may not be recoverable via higher layer retransmission (e.g., RLC layer retransmission). The MAC CE transmission may be allowed for the UL grant associated with the enabled HARQ feedback.

[0105] The WTRU may apply (or be configured to apply) a prioritization of logical channels based, for example, on HARQ characteristics associated with the UL grant. In an embodiment, for example, if the UL grant indicates (e.g., explicitly or implicitly) that HARQ feedback is enabled, the WTRU may apply a first prioritization order. For example, if the UL grant indicates (e.g., explicitly or implicitly) that HARQ feedback is disabled, the WTRU may apply a second prioritization order. In an embodiment of the first prioritization order, the Buffer Status Report (BSR) and Power Headroom (PHR) MAC CEs may have a lower priority than data from logical channels (e.g., other than the Uplink Shared Control Channel (UL-CCCH)). In an embodiment of the second prioritization order, the BSR and PHR MAC CEs may have a higher priority than data from logical channels (e.g., other than the UL-CCCH).

[0106] Systems and methods for overriding HARQ restrictions are described. The WTRU may start (e.g., be configured to start) a timer, e.g., when a MAC CE is triggered. The WTRU may reset the timer, e.g., when a MAC CE transmission is successful. The WTRU may transmit the MAC CE (e.g., while the timer is running), e.g., when an UL grant matches a preconfigured HARQ characteristic for the MAC CE. The WTRU may override the HARQ characteristic configuration and transmit the MAC CE in the earliest available UL grant, e.g., if the WTRU is unable to transmit the MAC CE before expiration of the timer.

[0107] The WTRU may, for example, skip HARQ feedback transmission if the received DL transport block is associated with an open-loop HARQ process type. The WTRU may override (e.g., be configured to override) a rule (e.g., a rule such as skipping HARQ feedback transmission if the received DL transport block is associated with an open-loop HARQ process type) based on, for example, the content of the MAC PDU. The WTRU may override the HARQ process type configuration and send HARQ feedback, for example, if the WTRU determines that the DL MAC PDU includes a MAC CE.

[0108] The WTRU may multiplex (e.g., be configured to multiplex) a first set of MAC CEs onto a transport block corresponding to the HARQ process(es) of a first type of HARQ process. Another set(s) of MAC CEs may be multiplexed onto a transport block corresponding to a second set of HARQ process(es). In an embodiment, the set of MAC CEs may depend on the type of MAC CE (e.g., BSR, PHR).

[0109] The UL power control may be based on the HARQ process. In an embodiment, the WTRU may associate one or more parameters and / or tables for power control with a set of HARQ process ID(s) and / or the applicable HARQ process type. Examples of parameters and / or tables include (a) a power offset that can increase / decrease the resulting power level for a transmission, (b) a fractional power value that can be used for fractional pathloss compensation, (c) a transmit power command (TPC) command mapping table that can map the TPC command field in the DCI to absolute power adjustments and / or cumulative power adjustments, (d) a target power P for a transmission, and / or (e) a power offset that can increase / decrease the resulting power level for a transmission. oThe adjustments may include one or more of: adjustments to the power settings and / or values.

[0110] The WTRU may be configured with a power offset value associated (e.g., may be associated with) an HARQ process type that may require HARQ retransmission. The WTRU may be configured with another power offset value that may be associated with another HARQ process type that may not require HARQ retransmission.

[0111] The WTRU may be configured with a TPC command mapping table that may be associated with HARQ process types that may not require HARQ retransmissions. The WTRU may be configured with another TPC command mapping table that may be associated with HARQ process types that may require HARQ retransmissions.

[0112] The WTRU may associate (e.g., be configured to associate) the TPC command mapping table with the HARQ process type (e.g., in a one-to-one relationship). The WTRU may be (e.g., further) configured to perform an operation (e.g., addition or multiplication using a parameter α) with the absolute power adjustment value and / or the accumulated power adjustment value depending on the HARQ process type. For example, the WTRU may be configured to apply a first operation (e.g., addition or multiplication) using a first parameter (e.g., a1) for the absolute power adjustment value and / or the accumulated power adjustment value associated with a first HARQ process type (e.g., the HARQ process type requires HARQ retransmission) and apply a second operation (e.g., addition or multiplication) using a second parameter (e.g., a2) for the absolute power adjustment value and / or the accumulated power adjustment value associated with a second HARQ process type (e.g., the HARQ process type does not require HARQ retransmission).

[0113] The WTRU may override (e.g., be configured to override) one or more TPC codepoints in the TPC command mapping table, e.g., to have a different meaning for the overridden codepoints. In an embodiment, the WTRU may override (e.g., be configured to override) a TPC codepoint in the TPC command mapping table, e.g., to indicate that the TPC codepoint in the TPC command is for the absolute "Pcmax".

[0114] The WTRU may use (e.g., be configured to use) a modulation and coding scheme (MCS) table for the type of HARQ process. In an embodiment, the WTRU may be configured with a table having a low block error rate (BLER) target. The MCS table (e.g., configured with a table having a low BLER target) may be used for HARQ process types that may not require HARQ retransmissions, for example. In an embodiment, the WTRU may be configured with a table having a high (higher) BLER target. The MCS table (e.g., configured with a table having a high (higher) BLER target) may be used for HARQ process types that may require HARQ retransmissions.

[0115] The WTRU may associate (e.g., be configured to associate) an MCS table with a TPC command mapping table, and / or vice versa. In an embodiment, the WTRU may use (e.g., be configured to use) one MCS table at a time. The WTRU may be configured to use a corresponding TPC command mapping table (e.g., based on an active MCS table) to interpret TPC commands, for example, for power control.

[0116] The WTRU may determine (e.g., be configured to determine) a HARQ behavior associated with a configured grant, e.g., based on a HARQ configuration. In an embodiment, the WTRU may determine a HARQ behavior associated with a configured grant, e.g., based on (e.g., implicitly based on) a HARQ configuration for a transmission associated with a dynamic grant. The WTRU may apply an open-loop HARQ functionality for a transmission associated with a configured grant, e.g., if open-loop HARQ is configured for the dynamic grant. In an embodiment, the WTRU may apply a HARQ functionality based, e.g., on HARQ processes assigned for the configured grant and the HARQ behavior (e.g., open / closed / stateless) configured for those HARQ processes.

[0117] In (e.g., additional and / or alternative) embodiments, the WTRU may apply (e.g., be configured to apply) differentiated HARQ functionality for a configured grant, e.g., as compared to a transmission with a dynamic grant. For example, the WTRU may apply (e.g., be configured to apply) HARQ behavior for a transmission without a dynamic grant (e.g., a configured grant). The HARQ behavior may be configured, e.g., via RRC signaling (e.g., in a configuredGrantConfig information element).

[0118] The WTRU may determine (e.g., be configured to determine) an HARQ type associated with A (e.g., each) resource in the configured grant. The WTRU may determine (e.g., be configured to determine) that the (e.g., each) resource can belong to or be associated with one or more HARQ types (e.g., stateless HARQ, open-loop HARQ, and / or closed-loop HARQ).

[0119] The HARQ type associated with each resource may be determined based on one or more parameters, for example, the number of HARQ processes assigned to the configured grant, the periodicity of the configured grant, the time interval between two consecutive HARQ processes, and / or the HARQ reuse time (e.g., the minimum time for the WTRU to reuse the same HARQ process). The WTRU may selectively buffer transmitted packets for possible HARQ retransmissions (e.g., by) not sacrificing the data rate, for example.

[0120] In (e.g., additional and / or alternative) embodiments, the WTRU may use (e.g., be configured to use) stateless HARQ transmission for resources in a configured grant. In embodiments, the WTRU may use (e.g., be configured to use) stateless HARQ transmission for resources in a configured grant, e.g., if one or more (e.g., each) of the HARQ processes assigned to the resources in the configured grant are in use.

[0121] FIG. 6 illustrates an example of a WTRU determining a HARQ type for each resource in a configured grant. As illustrated by the example in FIG. 6, the WTRU may have two HARQ processes (e.g., identified by PID1 and PID2) assigned to the configured grant. In an example (e.g., as shown in Option 1), a time interval of 2×periodicity may be configured for two consecutive HARQ processes (e.g., PID1 and PID2). In an (e.g., additional and / or alternative) example (e.g., as shown in Option 2), the time interval between two consecutive HARQ processes (e.g., PID1 and PID2) may not be configured. In an example (e.g., as shown in Option 1 and Option 2), the WTRU may determine (e.g., based on a configuration) a HARQ type associated with (e.g., each) resource in the configured grant.

[0122] While the solutions provided herein may describe examples related to LTE, LTE-A, New Radio (NR), or 5G specific protocols and may be described using non-terrestrial networks, it will be understood that the solutions described herein are not limited to those scenarios and may also be applicable to other wireless systems, deployments, or networks. The solutions discussed herein may be at least applicable to network deployments with similar characteristics in that they have long latencies, round trip time delays, and / or the network components (e.g., gNBs) are not fixed (e.g., satellite, aerial, etc.).

[0123] Although the features and elements have been described above in particular combinations, one skilled in the art will recognize that each feature or element may be used alone or in any combination with the other features and elements. In addition, the methods described herein may be implemented in a computer program, software, or firmware embodied in a computer-readable medium for execution by a computer or processor. Examples of computer-readable media include electrical signals (transmitted over wired or wireless connections) and computer-readable storage media. Examples of computer-readable storage media include, but are not limited to, read-only memory (ROM), random access memory (RAM), registers, cache memory, semiconductor memory devices, magnetic media such as internal hard disks and removable disks, magneto-optical media, and optical media such as CD-ROM disks and digital versatile disks (DVDs). A processor in conjunction 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. [Industrial Applicability]

[0124] The present invention can be used in communications.

Claims

1. 1. A wireless transmit / receive unit (WTRU), comprising: receiving configuration information including a first hybrid automatic repeat request (HARQ) behavior associated with a first HARQ identifier (ID) and a second HARQ behavior associated with a second HARQ ID; receiving a downlink grant (DL grant) indicating a HARQ ID, the HARQ ID being the first HARQ ID or the second HARQ ID; determining a HARQ behavior based on the indicated HARQ ID, where if the HARQ ID is the first HARQ ID, the HARQ behavior is determined to be the first HARQ behavior, and if the HARQ ID is the second HARQ ID, the HARQ behavior is determined to be the second HARQ behavior; sending a transmission associated with said determined HARQ behavior; On a condition that the HARQ behavior is determined to be the first HARQ behavior, the transmission includes HARQ feedback; On a condition that the HARQ behavior is determined to be the second HARQ behavior, the transmission excludes HARQ feedback. Processor configured for A WTRU equipped with

2. The WTRU of claim 1 , wherein the first HARQ behavior is associated with a closed-loop HARQ process, the closed-loop HARQ process being associated with transmitting HARQ feedback.

3. The WTRU of claim 1 , wherein the second HARQ behavior is associated with a stateless HARQ process, the stateless HARQ process being associated with the exclusion of HARQ feedback.

4. The WTRU of claim 1 , wherein the DL grant is associated with a downlink control information (DCI) indicating the HARQ ID.

5. 1. A method associated with Hybrid Automatic Repeat Request (HARQ) processing, comprising: receiving configuration information including a first hybrid automatic repeat request (HARQ) behavior associated with a first HARQ identifier (ID) and a second HARQ behavior associated with a second HARQ ID; receiving a downlink grant (DL grant) indicating a HARQ ID, the HARQ ID being the first HARQ ID or the second HARQ ID; determining a HARQ behavior based on the indicated HARQ ID, where if the HARQ ID is the first HARQ ID, the HARQ behavior is determined to be the first HARQ behavior, and if the HARQ ID is the second HARQ ID, the HARQ behavior is determined to be the second HARQ behavior; sending a transmission associated with the determined HARQ behavior, On a condition that the HARQ behavior is determined to be the first HARQ behavior, the transmission includes HARQ feedback; on a condition that the HARQ behavior is determined to be the second HARQ behavior, the transmission excludes HARQ feedback; A method for providing the above.

6. 6. The method of claim 5, wherein the first HARQ behavior is associated with a closed-loop HARQ process, the closed-loop HARQ process being associated with transmitting HARQ feedback.

7. 6. The method of claim 5, wherein the second HARQ behavior is associated with a stateless HARQ process, the stateless HARQ process being associated with the exclusion of HARQ feedback.

8. The method of claim 5 , wherein the DL grant is associated with a Downlink Control Information (DCI) indicating the HARQ ID.

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