Patent Description:
<NUM> NR is part of a continuous mobile broadband evolution promulgated by Third Generation Partnership Project (<NUM> GPP) to meet new requirements associated with latency, reliability, security, scalability (e.g., with Internet of Things (IoT)), and other requirements.

Storage media may be any available media that may be accessed by a computer. By way of example, and not limitation, such computer-readable media may comprise a random-access memory (RAM), a read-only memory (ROM), an electrically erasable programmable ROM (EEPROM), optical disk storage, magnetic disk storage, other magnetic storage devices, combinations of the aforementioned types of computer-readable media, or any other medium that may be used to store computer executable code in the form of instructions or data structures that may be accessed by a computer.

<FIG> is a diagram illustrating an example of a wireless communication system and an access network <NUM> in accordance with various aspects of the present disclosure. The wireless communication system (also referred to as a wireless wide area network (WWAN)) includes base stations <NUM>, UEs <NUM>, and an Evolved Packet Core (EPC) network <NUM>.

The base stations <NUM> (collectively referred to as Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN)) interface with the EPC network <NUM> through backhaul links <NUM> (e.g., S1 interface).

A network that includes both small cell and macro cells may be known as a heterogeneous network. The base stations <NUM> / UEs <NUM> may use spectrum up to fMHz (e.g., <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) bandwidth, for example, per carrier allocated in a carrier aggregation of up to a total of Yx MHz (x component carriers), used for transmission in each direction. Allocation of carriers may be asymmetric with respect to DL and UL (e.g., more or less carriers may be allocated for DL than for UL).

In aspects, the wireless communication system may further include a Wi-Fi access point (AP) <NUM> in communication with Wi-Fi stations (STAs) <NUM> via communication links <NUM> in a <NUM> unlicensed frequency spectrum.

A gNodeB (gNB) <NUM>, for example, may operate in millimeter wave (mmW) frequencies and/or near mmW frequencies in communication with the UE <NUM>.

The EPC network <NUM> may include a Mobility Management Entity (MME) <NUM>, other MMEs <NUM>, a Serving Gateway <NUM>, a Multimedia Broadcast Multicast Service (MBMS) Gateway <NUM>, a Broadcast Multicast Service Center (BM-SC) <NUM>, and a Packet Data Network (PDN) Gateway <NUM>. The IP Services <NUM> may include the Internet, an intranet, an IP Multimedia Subsystem (IMS), a PS Streaming Service (PSS), and/or other IP services.

An access point ("AP") may comprise, be implemented as, or known as a NodeB, a Radio Network Controller ("RNC"), an eNodeB (eNB), a Base Station Controller ("BSC"), a Base Transceiver Station ("BTS"), a Base Station ("BS"), a Transceiver Function ("TF"), a Radio Router, a Radio Transceiver, a Basic Service Set ("BSS"), an Extended Service Set ("ESS"), a Radio Base Station ("RBS"), a Node B (NB), a gNB, a <NUM> NB, aNRBS, a Transmit Receive Point (TRP), or some other terminology.

An access terminal ("AT") may comprise, be implemented as, or be known as an access terminal, a subscriber station, a subscriber unit, a mobile station, a remote station, a remote terminal, a user terminal, a user agent, a user device, user equipment (UE), a user station, a wireless node, or some other terminology. In some aspects, an access terminal may comprise a cellular telephone, a smart phone, a cordless telephone, a Session Initiation Protocol ("SIP") phone, a wireless local loop ("WLL") station, a personal digital assistant ("PDA"), a tablet, a netbook, a smartbook, an ultrabook, a handheld device having wireless connection capability, a Station ("STA"), or some other suitable processing device connected to a wireless modem. Accordingly, one or more aspects taught herein may be incorporated into a phone (e.g., a cellular phone, a smart phone), a computer (e.g., a desktop), a portable communication device, a portable computing device (e.g., a laptop, a personal data assistant, a tablet, a netbook, a smartbook, an ultrabook), wearable device (e.g., smart watch, smart glasses, smart bracelet, smart wristband, smart ring, smart clothing, and/or the like), medical devices or equipment, biometric sensors/devices, an entertainment device (e.g., music device, video device, satellite radio, gaming device, and/or the like), a vehicular component or sensor, smart meters/sensors, industrial manufacturing equipment, a global positioning system device, or any other suitable device that is configured to communicate via a wireless or wired medium. In some aspects, the node is a wireless node. A wireless node may provide, for example, connectivity for or to a network (e.g., a wide area network such as the Internet or a cellular network) via a wired or wireless communication link.

In aspects, NR UEs may be considered Enhanced Mobile Broadband (eMBB) UEs employing service targeting wide bandwidth (e.g., <NUM> megahertz (MHz) and beyond). In aspects, such service may include, for example, voice, messaging and/or video streaming services similar to LTE communication. Additionally, or alternatively, NR UEs may be considered millimeter wave (mmW) UEs targeting high carrier frequency (e.g., <NUM> gigahertz (GHz)) communication. Additionally, or alternatively, NR UEs may be considered ultra reliable and low latency communications (URLLC) UEs using mission critical URLLC service. In aspects, such service may include, for example, factory automation, robotics, remote surgery, and/or autonomous driving. Additionally, or alternatively, NR UEs may be considered machine-type communication (MTC) UEs, which may include remote devices that may communicate with a base station, another remote device, or some other entity. Machine type communications (MTC) may refer to communication involving at least one remote device on at least one end of the communication and may include forms of data communication which involve one or more entities that do not necessarily need human interaction. MTC UEs may include UEs that are capable of MTC communications with MTC servers and/or other MTC devices through Public Land Mobile Networks (PLMN), for example. Examples of MTC devices include sensors, meters, location tags, monitors, drones, robots/robotic devices, and/or the like. MTC UEs, as well as other types of UEs, may be implemented as NB-IoT (narrowband internet of things) devices. Additionally, or alternatively, NR UEs may be considered massive MTC (mMTC) UEs targeting non-backward compatible MTC techniques.

It is noted that while aspects may be described herein using terminology commonly associated with <NUM> and/or <NUM> wireless technologies, aspects of the present disclosure may be applied in other generation-based communication systems, such as <NUM> and later, including NR technologies.

In some aspects, the present disclosure is directed to supporting URLLC services (e.g., over TDD). URLLC services may include transmission and reception of URLLC data. Such transmissions and receptions may often have low latency and high reliability requirements. Unfortunately, the nominal structure of an enhanced mobile broadband (eMBB) TDD subframe has several fundamental limitations that restrict the reliability and latency achievements that may be obtained. For example, although a nominal TDD subframe may be self-contained, in that it may contain a downlink (DL) interval and an uplink (UL) interval, in the nominal TDD subframe structure only one direction in downlink or uplink may be active at any time. This feature creates a self-blocking characteristic in the nominal TDD subframe structure. Thus, during uplink intervals, no downlink transmissions are possible. Similarly, during downlink intervals, no uplink transmissions are possible.

In aspects, URLLC services may be associated with a requirement of <NUM>-<NUM> error probability (e.g., in transmitting a layer <NUM> PDU of <NUM> bytes within <NUM>). For communication availability and resilience, and user plane latency of delivery (e.g., of a packet of size <NUM> bytes), requirements for D2D communication, like enhanced V2X communication, may be as follows (<NUM>) Reliability = <NUM>-<NUM>, and user plane latency = <NUM>-<NUM> msec, for direct communication via sidelink and communication range of (e.g., a few meters); and (<NUM>) Reliability = <NUM>-<NUM>, and user plane latency = <NUM>-<NUM> msec, when the packet is relayed via BS.

Thus, a deadline constraint for the communication of URLLC data may exist. For example, a delay budget consisting of a particular period of time or number of symbols may be provided. Given the deadline constraint, URLLC data may be successfully delivered within the delay budget. Because of the self-blocking limitation of the nominal TDD subframe structure, a large nominal TDD subframe structure limits the number of possible URLLC data transmissions within the given delay budget and thus, the highest system reliability that may be achieved. As described below, the present disclosure provides a solution to these, and other problems, by providing a URLLC frame configuration (e.g., subframe configuration) that takes into account the limitations of the nominal TDD subframe.

Referring again to <FIG>, in certain aspects, the UE <NUM> may be configured to perform a communication with a second UE <NUM>' for a device-to-device (D2D) communication. In aspects, such communication by the UE <NUM> may be a sidelink communication (e.g., using a carrier <NUM> like a sidelink carrier) with a second UE <NUM>' for a device-to-device (D2D) communication. In aspects, the D2D communication may include a vehicle-to-everything (V2X) communication or a vehicle-to-vehicle (V2V) communication. The UE <NUM> may communicate with a second UE <NUM>' via the carrier <NUM> using one or more sidelink communication structures having at least one feedback symbol. In an aspect, at least a portion of a plurality of frequency bands for the carrier <NUM> corresponds to an Intelligent Transport System frequency spectrum for a sidelink carrier. In aspects, the D2D communication may include NR D2D URLLC communication as described herein.

<FIG> is a diagram <NUM> illustrating an example frame structure of one or more downlink (DL) frames in accordance with various aspects of the present disclosure. <FIG> is a diagram <NUM> illustrating an example of channels within the frame structure of a DL frame in accordance with various aspects of the present disclosure. <FIG> is a diagram <NUM> illustrating an example frame structure of one or more uplink (UL) frames in accordance with various aspects of the present disclosure. <FIG> is a diagram <NUM> illustrating an example of channels within the frame structure of a UL frame in accordance with various aspects of the present disclosure. A frame (<NUM>) may be divided into <NUM> equally sized subframes. Each subframe may include two consecutive time slots. A resource grid may be used to represent the two time slots, each time slot including one or more time concurrent resource blocks (RBs) (also referred to as physical RBs (PRBs)). For a normal cyclic prefix, an RB contains <NUM> consecutive subcarriers (e.g., for <NUM> subcarrier spacing) in the frequency domain and <NUM> consecutive symbols (for DL, OFDM symbols; for UL, SC-FDMA symbols) in the time domain, for a total of <NUM> REs. For an extended cyclic prefix, an RB contains <NUM> consecutive subcarriers in the frequency domain and <NUM> consecutive symbols in the time domain, for a total of <NUM> REs.

As illustrated in <FIG>, some of the REs carry DL reference (pilot) signals (DL-RS) for channel estimation at the UE. The DL-RS may include cell-specific reference signals (CRS) (e.g., also sometimes called common RS), UE-specific reference signals (UE-RS), and channel state information reference signals (CSI-RS). <FIG> illustrates CRS for antenna ports <NUM>, <NUM>, <NUM>, and <NUM> (indicated as R<NUM>, R<NUM>, R<NUM>, and R<NUM>, respectively), UE-RS for antenna port <NUM> (indicated as R<NUM>), and CSI-RS for antenna port <NUM> (indicated as R). <FIG> illustrates an example of various channels within a DL subframe of a frame. The physical control format indicator channel (PCFICH) is within symbol <NUM> of slot <NUM>, and carries a control format indicator (CFI) that indicates whether the physical downlink control channel (PDCCH) occupies <NUM>, <NUM>, or <NUM> symbols (<FIG> illustrates a PDCCH that occupies <NUM> symbols). The PDCCH carries downlink control information (DCI) within one or more control channel elements (CCEs), each CCE including nine RE groups (REGs), each REG including four consecutive REs in an OFDM symbol. A UE may be configured with a UE-specific enhanced PDCCH (ePDCCH) that also carries DCI. The ePDCCH may have <NUM>, <NUM>, or <NUM> RB pairs (<FIG> shows two RB pairs, each subset including one RB pair). The physical hybrid automatic repeat request (ARQ) (HARQ) indicator channel (PHICH) is also within symbol <NUM> of slot <NUM> and carries the HARQ indicator (HI) that indicates HARQ acknowledgement (ACK) / negative ACK (NACK) feedback based on the physical uplink shared channel (PUSCH). The primary synchronization channel (PSCH) may be within symbol <NUM> of slot <NUM> within subframes <NUM> and <NUM> of a frame. The PSCH carries a primary synchronization signal (PSS) that is used by a UE to determine subframe/symbol timing and a physical layer identity. The secondary synchronization channel (SSCH) may be within symbol <NUM> of slot <NUM> within subframes <NUM> and <NUM> of a frame. The SSCH carries a secondary synchronization signal (SSS) that is used by a UE to determine a physical layer cell identity group number and radio frame timing. Based on the physical layer identity and the physical layer cell identity group number, the UE may determine a physical cell identifier (PCI). Based on the PCI, the UE may determine the locations of the aforementioned DL-RS. The physical broadcast channel (PBCH), which carries a master information block (MIB), may be logically grouped with the PSCH and SSCH to form a synchronization signal (SS) block. The MIB provides a number of RBs in the DL system bandwidth, a PHICH configuration, and a system frame number (SFN).

As illustrated in <FIG>, some of the REs carry demodulation reference signals (DM-RS) for channel estimation at the base station. The UE may additionally transmit sounding reference signals (SRS) in the last symbol of a subframe. <FIG> illustrates an example of various channels within an UL subframe of a frame. A physical random access channel (PRACH) may be within one or more subframes within a frame based on the PRACH configuration. The PRACH may include six consecutive RB pairs within a subframe. The PRACH allows the UE to perform initial system access and achieve UL synchronization. A physical uplink control channel (PUCCH) may be located on edges of the UL system bandwidth.

<FIG> is a block diagram of a base station <NUM> in communication with a UE <NUM> in an access network in accordance with various aspects of the present disclosure. In the DL, IP packets from the EPC network <NUM> may be provided to a controller/processor <NUM>.

The controller/processor <NUM> may be associated with a memory <NUM> that stores program codes and data.

The controller/processor <NUM> may be associated with a memory <NUM> that stores program codes and data.

One or more components of UE <NUM> may be configured to perform methods of NR D2D URLLC communication, as described in more detail elsewhere herein. For example, the controller/processor <NUM> and/or other processors and modules of UE <NUM> may perform or direct operations of, for example, process <NUM> of <FIG>, process <NUM> of <FIG>, and/or other processes as described herein. In some aspects, one or more of the components shown in <FIG> may be employed to perform example process <NUM> of <FIG>, process <NUM> of <FIG>, and/or other processes as described herein.

In some aspects, UE <NUM> may include means for transmitting data associated with an ultra-reliable and low-latency communications (URLLC) communication in a first set of one or more portions of a wireless communication structure having a plurality of portions, and means for re-transmitting the data associated with the URLLC communication in a second set of one or more portions of the wireless communication structure, wherein one or more slot structures of the wireless communication structure are defined by the plurality of portions, the first set of one or more portions is based on a first mini-slot structure, the second set of one or more portions is based on a second mini-slot structure, and a mini-slot structure is smaller than a slot structure. In some aspects, UE <NUM> may include means for receiving data associated with an ultra-reliable and low-latency communications (URLLC) communication in a first set of one or more portions of a wireless communication structure having a plurality of portions, and means for receiving the data associated with the URLLC communication re-transmitted in a second set of one or more portions of the wireless communication structure, wherein one or more slot structures of the wireless communication structure are defined by the plurality of portions, the first set of one or more portions is based on a first mini-slot structure, the second set of one or more portions is based on a second mini-slot structure, and a mini-slot structure is smaller than a slot structure. In some aspects, such means may include one or more components of UE <NUM> described in connection with <FIG>.

<FIG> is a diagram of a device-to-device (D2D) communication system <NUM> which, for example, may include vehicle-to-everything (V2X) communication system and/or vehicle-to-vehicle (V2V) communication system in accordance with various aspects of the present disclosure. For example, the D2D communication system <NUM> may include a first vehicle <NUM>' that communicates with a second vehicle <NUM>'. In some aspects, the first vehicle <NUM>' and/or the second vehicle <NUM>' may be configured to communicate in a specific spectrum, such as an intelligent transport systems (ITS) spectrum. The ITS spectrum may be unlicensed, and therefore a plurality of different technologies may use the ITS spectrum for communication, including LTE, LTE-Advanced, Licensed Assisted Access (LAA), Dedicated Short Range Communications (DSRC), <NUM>, new radio (NR), <NUM>, and the like. The foregoing list of technologies is to be regarded as illustrative, and is not meant to be exhaustive.

The D2D communication system <NUM> may utilize LTE technology or another technology (e.g., <NUM> NR). For example, a vehicle in D2D communication may incorporate therein a UE of the LTE or <NUM> NR technology. In D2D communication (e.g., V2X communication or V2V communication), the vehicles <NUM>', <NUM>' may be on networks of different mobile network operators (MNOs). Each of the networks may operate in its own frequency spectrum. For example, the air interface to a first vehicle <NUM>' (e.g., the Uu interface) may be on one or more frequency bands different from the air interface of the second vehicle <NUM>'. The first vehicle <NUM>' and the second vehicle <NUM>' may communicate via a sidelink (e.g., using a carrier <NUM> like a sidelink carrier), for example, via the PC5 interface. In some examples, the MNOs may schedule sidelink communication between or among the vehicles <NUM>', <NUM>' in V2X spectrum (e.g., V2V spectrum). An example of the V2X spectrum may include the intelligent transport system (ITS) frequency spectrum. The ITS spectrum may be unlicensed, and therefore a plurality of different technologies may use the ITS spectrum for communication, including LTE, LTE-Advanced, Licensed Assisted Access (LAA), Dedicated Short Range Communications (DSRC), <NUM>, new radio (NR), <NUM>, and the like. The foregoing list of technologies is to be regarded as illustrative, and is not meant to be exhaustive. However, in some aspects, a D2D communication (e.g., a sidelink communication) between or among vehicles <NUM>', <NUM>' is not scheduled by MNOs.

The D2D communication system <NUM> may be present where devices (e.g., vehicles) operate in networks of different MNOs and/or different frequency spectrums. For example, each of the vehicles in a D2D (e.g., V2V or V2X) communication system may have a subscription from a respective corresponding MNO. The V2X spectrum may be shared with the frequency spectrums of the MNOs. In some examples, the D2D (e.g., V2V or V2X) communication system <NUM> may be deployed where the first vehicle <NUM>' operates in the network operated by a first MNO, and the second vehicle <NUM>' is not in a network - e.g., the V2X spectrum may have no network deployed.

The first vehicle <NUM>' may be in D2D (e.g., V2V or V2X) communication with the second vehicle <NUM>'. The first vehicle <NUM>' incorporates the first UE <NUM>, and the second vehicle <NUM>' incorporates the second UE <NUM>. The first UE <NUM> may operate on a first network <NUM> (e.g., of the first MNO). In aspects, the D2D communication system <NUM> may further include a third vehicle <NUM>' that incorporates a third UE <NUM>. The third UE <NUM> may operate on the first network <NUM> (e.g., of the first MNO) or another network, for example. The third vehicle <NUM>' may be in D2D (e.g., V2V or V2X) communication with the first vehicle <NUM>' and/or second vehicle <NUM>'.

The first network <NUM> operates in a first frequency spectrum and includes the first base station <NUM> communicating at least with the first UE <NUM>, for example, as described in <FIG>. The first base station <NUM> may communicate with the first UE <NUM> via a DL carrier <NUM> and/or an UL carrier <NUM>. The DL communication may be performed via the DL carrier <NUM> using various DL resources (e.g., the DL subframes (<FIG>) and/or the DL channels (<FIG>)). The UL communication may be performed via the UL carrier <NUM> using various UL resources (e.g., the UL subframes (<FIG>) and the UL channels (<FIG>)).

In some aspects, the second UE <NUM> may not be on a network. In some aspects, the second UE <NUM> may be on a second network <NUM> (e.g., of the second MNO). The second network <NUM> may operate in a second frequency spectrum (e.g., a second frequency spectrum different from the first frequency spectrum) and may include the second base station <NUM> communicating with the second UE <NUM>, for example, as described in <FIG>.

The second base station <NUM> may communicate with the second UE <NUM> via a DL carrier <NUM> and an UL carrier <NUM>. The DL communication is performed via the DL carrier <NUM> using various DL resources (e.g., the DL subframes (<FIG>) and/or the DL channels (<FIG>)). The UL communication is performed via the UL carrier <NUM> using various UL resources (e.g., the UL subframes (<FIG>) and/or the UL channels (<FIG>)).

The D2D (e.g., V2V or V2X) communication may be carried out via one or more carriers (e.g., sidelink carriers) <NUM>, <NUM>. The one or more carriers <NUM>, <NUM> may include one or more channels, such as a physical sidelink broadcast channel (PSBCH), a physical sidelink discovery channel (PSDCH), a physical sidelink shared channel (PSSCH), and a physical sidelink control channel (PSCCH), for example.

In some examples, the carriers <NUM>, <NUM> may operate using the PC5 interface. The first UE <NUM> (e.g., incorporated in the first vehicle <NUM>') may transmit to one or more (e.g., multiple) devices, including to the second UE <NUM> (e.g., incorporated in the second vehicle <NUM>') via the first carrier <NUM>. The second UE <NUM> may transmit to one or more (e.g., multiple) devices, including to the first UE <NUM> (e.g., incorporated in the vehicle <NUM>') via the second carrier <NUM>.

In some aspects, the UL carrier <NUM> and the first carrier <NUM> may be aggregated to increase bandwidth. In some aspects, the first carrier <NUM> and/or the second carrier <NUM> may share the first frequency spectrum (with the first network <NUM>) and/or share the second frequency spectrum (with the second network <NUM>). In some aspects, the first and second carriers <NUM>, <NUM> may operate in an unlicensed spectrum.

Various use cases exist for D2D communication. For intelligent transport systems and/or infrastructure backhaul, an exemplary communication (e.g., traffic light information) flow may include traffic control center (TCC) → Roadside Unit (RSU) → vehicle). An additional or alternative exemplary communication (e.g., collection of vehicle probe data) flow may include vehicle → RSU → TCC. For reliable distribution of data, low-latency and/or high-capacity connections between RSUs (e.g. traffic lights, traffic signs, etc.) and the TCC is required. Similarly, low-latency and communication is required between RSU and Vehicles. For example, tight end-to-end latency of a few ms with reliability of the communication service of <NUM>% may be required to compete with existing wired technology and/or to justify the costly deployment and maintenance of RSUs. An additional or alternative use case may include message exchanges for co-operative driving with intention sharing where vehicles dynamically change decisions to change their path and direction.

An additional or alternative use case for D2D communication may include sensor and/or trajectory information sharing which may have an arbitrary traffic pattern. For example, sensor information for a number of detected objects on the road and/or a field of view information associated with a vehicle may be transmitted.

The exemplary methods and apparatuses discussed infra are applicable to any of a variety of wireless D2D (e.g., V2V or V2X) communication systems. To simplify the discussion, the exemplary methods and apparatus may be discussed within the context of LTE and/or NR. However, one of ordinary skill in the art would understand that the exemplary methods and apparatuses are applicable more generally to a variety of other wireless D2D (e.g., V2V or V2X) communication systems.

In aspects, a D2D communication on the one or more carriers <NUM>, <NUM> may occur between the first UE <NUM> (e.g., incorporated in the first vehicle <NUM>') and the second UE <NUM> (e.g., incorporated in the second vehicle <NUM>'). In an aspect, the first UE <NUM> (e.g., incorporated in the first vehicle <NUM>') may perform a D2D communication with one or more (e.g., multiple) devices, including to the second UE <NUM> (e.g., incorporated in the second vehicle <NUM>') via the first carrier <NUM>. For example, the first UE <NUM> may transmit a broadcast transmission via the first carrier <NUM> to the multiple devices (e.g., the second and third UEs <NUM>, <NUM>). The second UE <NUM> (e.g., among other UEs) may receive such broadcast transmission. Additionally, or alternatively, the first UE <NUM> may transmit a multicast transmission via the first carrier <NUM> to the multiple devices. The second UE <NUM> (e.g., among other UEs) may receive such multicast transmission. Further, additionally or alternatively, the first UE <NUM> may transmit a unicast transmission via the first carrier <NUM> to a device, such as the second UE <NUM>. The second UE <NUM> (e.g., among other UEs) may receive such unicast transmission. Additionally, or alternatively, in an aspect, the second UE <NUM> (e.g., incorporated in the second vehicle <NUM>') may perform a D2D communication with one or more (e.g., multiple) devices, including the first UE <NUM> (e.g., incorporated in the first vehicle <NUM>') via the second carrier <NUM>. For example, the second UE <NUM> may transmit a broadcast transmission via the second carrier <NUM> to the multiple devices. The first UE <NUM> (e.g., among other UEs) may receive such broadcast transmission. Additionally, or alternatively, the second UE <NUM> may transmit a multicast transmission via the second carrier <NUM> to the multiple devices (e.g., the first and third UEs <NUM>, <NUM>). The first UE <NUM> (e.g., among other UEs) may receive such multicast transmission. Further, additionally or alternatively, the second UE <NUM> may transmit a unicast transmission via the second carrier <NUM> to a device, such as the first UE <NUM>. The first UE <NUM> (e.g., among other UEs) may receive such unicast transmission. The third UE <NUM> may communicate in a similar manner.

In aspects, for example, such a D2D communication on the one or more carriers between the first UE <NUM> and the second UE <NUM> may occur without having MNOs allocating resources (e.g., one or more portions of a resource block (RB), slot, frequency band and/or channel associated with the one or more carriers <NUM>, <NUM>) for such communication and/or without scheduling such communication. In aspects, a D2D communication may include a traffic communication (e.g., a data communication, control communication, a paging communication and/or a system information communication). Further, in aspects, a D2D communication may include a feedback communication via the one or more carriers <NUM>, <NUM> associated with a traffic communication (e.g., a transmission of feedback information for a previously-received traffic communication). A feedback portion of the D2D communication structure may allot for any D2D communication feedback information that may be communicated in the device-to-device (D2D) communication system <NUM> between devices (e.g., a first vehicle <NUM>' and a second vehicle <NUM>'). In aspects, a D2D communication may be associated with one or more transmission time intervals (TTIs). In aspects, a TTI may be. Although a larger or smaller value may be employed. In aspects, a D2D communication may employ at least one first wireless communication structure having a plurality of portions, wherein one or more slot structures of the first wireless communication structure are defined by the plurality of portions. In aspects, such D2D communication may be associated with and/or correspond with a slot structure. In aspects, a TTI may be associated with and/or correspond to a communication structure slot.

While such first wireless communication structure having one or more slot structures may be useful for normal NR D2D communication, another wireless communication structure that provides increased reliability and/or reduced latency may be useful for UEs employing mission critical URLLC service, like NR D2D URLLC communication. For example, a wireless communication structure that provides a finer granularity of frequency and/or time resource utilization than the wireless communication structure used for normal NR D2D communication may be useful. Thus, in aspects, a D2D communication may employ at least one second wireless communication structure having a plurality of portions (e.g., symbols), wherein one or more slot structures of the second wireless communication structure are defined by the plurality of portions, a first set of one or more portions of the plurality of portions is based on a first mini-slot structure, and a second set of one or more portions of the plurality of portions is based is based on a second mini-slot structure, wherein a mini-slot structure is smaller than a slot structure. In aspects, such D2D communication may be associated with and/or correspond with a mini-slot structure. In aspects, the D2D communication may be associated with one or more portions of one or more transmission time intervals (TTIs). In aspects, a TTI may be. Although a larger or smaller value may be employed. In aspects, a TTI may be associated with and/or correspond to a communication structure slot.

<FIG> is a diagram illustrating an example first wireless communication structure <NUM> (e.g., a first 5GNRD2D communication structure) in accordance with various aspects of the present disclosure. The first wireless communication structure <NUM> may be defined by resources in a frequency domain and time domain. For example, the first wireless communication structure <NUM> may represent a time slot <NUM> and/or correspond to a TTI <NUM> (e.g.,. A resource grid may be used to represent the time slot <NUM> including one or more time concurrent resource blocks (RBs) (also referred to as physical RBs (PRBs)). In aspects, an RB <NUM> includes <NUM> consecutive subcarriers (e.g., having <NUM> subcarrier spacing) <NUM> in the frequency domain and <NUM> consecutive symbols <NUM> in the time domain, for a total of <NUM> REs. In aspects, an RB contains <NUM> consecutive subcarriers in the frequency domain and <NUM> consecutive symbols in the time domain, for a total of <NUM> REs. In aspects, a device (e.g., the first vehicle <NUM>' or UE <NUM>) may employ a plurality of resources blocks (e.g., N RBs) for a NR D2D communication (e.g., a sidelink transmission) <NUM> in the D2D communication system <NUM>. The NR D2D communication <NUM> may correspond to a single TTI.

In aspects, one or more symbols <NUM> (e.g., one or more of the first three symbols <NUM>) of the wireless communication structure <NUM> may be employed to communicate a listen-before-talk (LBT) sequence in a NR D2D communication. Transmission of the NR D2D communication by a device may be based on the LBT sequence. In aspects, one or more symbols (e.g., the fourth symbol <NUM>) of the wireless communication structure <NUM> may be employed to communicate control information in a NR D2D communication (e.g., by the device). In aspects, one or more symbols <NUM> (e.g., the fifth through thirteenth symbols <NUM>) of the wireless communication structure <NUM> may be employed to communicate data of a NR D2D communication (e.g., by the device). In aspects, one or more symbols <NUM> (e.g., the fourteenth symbol <NUM>) of the wireless communication structure <NUM> may be as a guard period to accommodate uplink-downlink switching (e.g., turnaround) time and/or the feedback portion (e.g., in which the device may receive feedback information).

In aspects, for example, the NR D2D communication structure <NUM> may be employed for a unicast NR D2D communication. In aspects, for example, the NR D2D communication structure <NUM> may be employed for a broadcast NR D2D communication. For example, the NR D2D communication structure <NUM> may be employed for a broadcast NR D2D transmission from a device (e.g., the first vehicle <NUM>') in the D2D communication system <NUM> to a plurality of other devices (e.g., including the second vehicle <NUM>') device in the D2D communication system <NUM>. In aspects, for example, the NR D2D communication structure <NUM> may be employed for a multicast NR D2D communication. For example, the NR D2D communication structure <NUM> may be employed for a multicast NR D2D transmission from a device (e.g., the first vehicle <NUM>') in the D2D communication system <NUM> to a plurality of other devices (e.g., including the second vehicle <NUM>') device in the D2D communication system <NUM>. The NR D2D communication structure <NUM> described above is exemplary and may be defined differently in the time and/or frequency domain. Additionally, or alternatively, the NR D2D communication structure <NUM> may be differently associated with a TTI (e.g., correspond to one or more portions of a TTI). While the NR D2D communication structure <NUM> may provide suitable and/or acceptable reliability and/or latency for normal NR D2D communication, such reliability and/or latency may not be suitable and/or acceptable for mission critical URLLC service, like NR D2D URLLC communication. For example, since a NR D2D URLLC communication may be associated with less data traffic bits than a NR D2D normal communication, employing a NR D2D communication structure <NUM> having such control, data, and/or gap overhead for NR D2D URLLC communication may be inefficient.

In aspects, the present methods and apparatus provide for NR D2D URLLC communication. NR D2D normal communication and NR D2D URLLC communication may co-exist (e.g., for better resource utilization), such that a same time/frequency resource may be used for either NR D2D normal communication or NR D2D URLLC communication, as needed. Although, in some aspects, separate time/frequency resources may be used for NR D2D normal communication and NR D2D URLLC communication. In aspects, NR D2D URLLC communication may be employed in a coverage area and/or out of a coverage area (e.g., via URLLC sidelink communication). A NR D2D communication may be autonomously performed by a UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> or scheduled by a base station <NUM>.

For NR D2D normal communication and NR D2D URLLC communication to co-exist, overlapping slot(s) and mini-slot(s) may be employed. All resources or subset of resources may be shared between normal traffic and URLLC traffic. Such arrangement of resources may be pre-configured or determined based on some other mechanism. In this manner, a better granularity for URLCC resources may be employed.

In aspects, a NR D2D URLLC transmission of data may be less than the normal TTI for NR D2D normal transmission of data (e.g., <NUM>). Using <NUM> symbols of <NUM> each for a mini-slot, for example, results in approximately a <NUM> mini-slot (e.g., for NR D2D URLLC). In aspects, a <NUM> OFDM symbol mini-slot for URLLC may be supported, for example, based on random selection of URLLC resources (e.g., of a <NUM> OFDM symbol mini-slot) and sensing of unused resources. In aspects, NR D2D URLLC communication may be associated with small packets (e.g., ~<NUM> bytes) similar to Uu interface URLLC communication. In aspects, NR D2D URLLC communication may be multicast, broadcast, and/or unicast communication. In aspects, a slot boundary and/or mini-slot boundary may be aligned with a symbol boundary. In aspects, a mini-slot boundary may be aligned with a slot boundary. For example, suitable numerologies may be employed for such alignment. In aspects, a UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> wanting to communicate a NR D2D URLLC communication may employ an LBT symbol to indicate reservation to another UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> wanting to communicate a NR D2D normal communication.

<FIG> is a diagram illustrating NR D2D (e.g., V2V or V2X) ultra-reliable and low-latency communications (URLLC) communication <NUM> in accordance with various aspects of the present disclosure. For example, a wireless communication structure <NUM> (e.g., a NR D2D URLLC wireless communication structure) may be employed for the NR D2D URLLC communication in accordance with various aspects of the present disclosure. The wireless communication structure <NUM> may be defined by resources in a frequency domain and time domain. In aspects, the wireless communication structure <NUM> may have a plurality of portions (e.g., symbols), wherein one or more slot structures <NUM> of the second wireless communication structure are defined by the plurality of portions, a first set of one or more portions of the plurality of portions is based on a first mini-slot structure <NUM>, and a second set of one or more portions of the plurality of portions is based is based on a second mini-slot structure <NUM>, wherein a mini-slot structure is smaller than a slot structure. For example, similar to the wireless communication structure <NUM>, the wireless communication structure <NUM>, may be associated with a time slot <NUM> and/or correspond to a TTI <NUM> (e.g.,. A resource grid may be used to represent the time slot <NUM> including one or more time concurrent resource blocks (RBs) (also referred to as physical RBs (PRBs)). In aspects, an RB <NUM> includes <NUM> consecutive subcarriers (e.g., having <NUM> subcarrier spacing) in the frequency domain and <NUM> consecutive symbols <NUM> in the time domain, for a total of <NUM> REs. In aspects, an RB contains <NUM> consecutive subcarriers in the frequency domain and <NUM> consecutive symbols in the time domain, for a total of <NUM> REs. Although the first mini-slot <NUM> and the second mini-slot <NUM> shown in <FIG> employ the same frequency resources, in aspects, the second mini-slot <NUM> may be associated with or employ different frequency resources than the frequency resources associated with or employed by the first mini-slot <NUM>. Such different frequency resources associated with or employed by the second mini-slot <NUM> may be mutually exclusive of or partially overlap with the frequency resources associated with or employed by the first mini-slot <NUM>. For example, frequency hopping, for retransmission (e.g., of the data) in second mini-slot <NUM> may provide some advantage (e.g., diversity). In aspects, a portion may be associated with a symbol, such that the wireless communication structure <NUM> is associated with a plurality of symbols which define a slot, and respective subsets of the plurality of symbols define a plurality of mini-slots. For example, the wireless communication structure <NUM> may be associated with a first mini-slot <NUM> and a second mini-slot <NUM>. The time slot <NUM> may be associated with <NUM> consecutive symbols <NUM> in the time domain. The first mini-slot <NUM> may be associated with a first subset (e.g., the first seven symbols) of such <NUM> consecutive symbols and the second mini-slot <NUM> may be associated with a second subset (e.g., the last seven symbols) of such <NUM> consecutive symbols. Although the first mini-slot <NUM> and/or the second mini-slot <NUM> may include a larger or smaller number of symbols.

In aspects, for a NR D2D URLLC communication, the wireless communication structure <NUM> may be employed to communicate (e.g., transmit) data associated with NR D2D URLLC communication 609a using the first mini-slot <NUM> and re-communicate (e.g., re-transmit) the data using the second mini-slot <NUM>. For such NR D2D URLLC communication a reliability is increased and/or latency is decreased (e.g., based on the repetition of data).

Wireless communication structure 601a illustrates first exemplary details of the first mini-slot <NUM> and the second mini-slot <NUM>. For example, the time slot <NUM> may be associated with <NUM> consecutive symbols <NUM> in the time domain, the first mini-slot <NUM> may be associated with the first seven symbols, and the second mini-slot <NUM> may be associated with the last seven symbols.

The first mini-slot may include a request-to-send (RTS) portion <NUM>, a first gap portion <NUM>, a clear-to-send (CTS) portion <NUM>, a second gap portion <NUM>, a control portion <NUM>, and a first data portion <NUM>. For example, the RTS portion <NUM>, first gap portion <NUM>, CTS portion <NUM>, second gap portion <NUM>, control portion <NUM> and first data portion <NUM> may be associated with and/or correspond to a first symbol <NUM>, second symbol <NUM>, third symbol <NUM>, fourth symbol <NUM>, fifth symbol <NUM>, and sixth through seventh symbols <NUM> of the time slot <NUM>, respectively. During the RTS portion <NUM>, one or more UEs <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> in the NR D2D system <NUM> may monitor for a request-to-send signal from another UE <NUM> indicating such UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> would like to transmit a NR D2D communication (e.g., NR D2D URLLC communication) during the slot <NUM>. A UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> that would like to transmit a communication during the slot <NUM> will transmit the RTS signal during the RTS portion. The first gap portion <NUM> may accommodate for uplink-downlink switching (e.g., turnaround) time for a UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM>. In response, during the CTS portion <NUM>, the one or more UEs <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> receiving the RTS signal may transmit a CTS signal indicating the UE <NUM> that transmitted the RTS signal may transmit the D2D communication in the slot <NUM>. Further, during the CTS portion <NUM>, the UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> that transmitted the RTS signal may monitor for such CTS signal(s) from the one or more other UEs <NUM>. The second gap portion <NUM> may accommodate for uplink-downlink switching (e.g., turnaround) time of a UE <NUM>. In this manner, a UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> receiving the one or more CTS(s) may prepare to transmit the D2D communication in the slot <NUM>. In aspects, as part of the D2D communication the UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> may transmit control information, in part, indicating characteristics of one or more data sections of the D2D communication. For example, the control information may include an indication of amounts of data transmitted and/or a modulation and coding schemes associated with the one or more data sections, respectively. In aspects, the control information may be included in the control portion <NUM>. The data portion <NUM> may include data associated with the D2D communication.

The second mini-slot <NUM> may include a second data portion <NUM>, a third gap portion <NUM>, and an acknowledgment (e.g., negative acknowledgement message (NAK)) portion <NUM>. For example, the second data portion <NUM>, the third gap portion <NUM>, and the acknowledgment portion <NUM> may be associated with and/or correspond to an eighth through twelfth symbols <NUM>, thirteenth symbol <NUM>, and fourteenth symbol <NUM>, respectively, of the time slot <NUM>. The second data portion <NUM> may include data associated with the D2D communication re-transmitted. However, since a number of symbols associated with the second data portion <NUM> may be greater than the number of symbols associated with the first data portion <NUM>, the retransmitted data of the D2D communication may have more redundant bits that the data of the D2D communication in the first data portion <NUM>. The third gap portion <NUM> may accommodate for uplink-downlink switching (e.g., turnaround) time a UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM>. In this manner, a UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> (e.g., transmitting the data) may prepare to monitor for and possibly receive, in the acknowledgment portion <NUM>, an acknowledgment message (e.g., NAK) associated with a previous transmission. If a UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM>, receives a NAK for a previous NR D2D transmission, the UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> may retransmit the NR D2D communication as described below with reference to <FIG>.

In some aspects, the second mini-slot <NUM> may include a control portion <NUM> for control information associated with the data in the data portion <NUM> of the second mini-slot <NUM>. The control portion <NUM> may include an indicator that the data portion <NUM> includes retransmitted data (e.g., a retransmitted version of the data transmitted in the first slot <NUM> for the NR D2D communication. In this manner, the indicator may be a re-transmission indicator. In such aspects, a size of the control portion <NUM> may be associated with one or more portions of a symbol <NUM> of the second mini-slot <NUM>, and the second data portion <NUM>, the third gap portion <NUM>, and/or the acknowledgment portion <NUM> may be reduced accordingly in the time and/or frequency domain. In aspects, the second mini-slot <NUM> including the re-transmitted data may have such control portion <NUM>, while the first mini-slot <NUM> including the data may not have such control portion <NUM>. In aspects, the control portion <NUM> in the second mini-slot <NUM> may be smaller than control portion <NUM> in the first mini-slot <NUM>. In aspects, data in the data portion <NUM> of the first mini-slot <NUM> may be independently decodable. Further, data in the data portion <NUM> of the second mini-slot <NUM> may be independently decodable.

While wireless communication structure 601a includes a control portion <NUM> in the first mini-slot <NUM>, aspects of the present methods and apparatus may employ a wireless communication structure that does not include such control portion. For example, wireless communication structure 601b illustrates second exemplary details of the first mini-slot <NUM>. Wireless communication structure 601b may be similar to wireless communication structure 601a. However, the wireless communication structure 601b may not include the control portion <NUM>. Control information, in part, indicating characteristics of one or more data sections of the D2D communication 609b may be included in the RTS portion <NUM> (e.g., as part of an RTS signal). In such aspects, a size of the RTS portion <NUM>, first gap portion <NUM>, CTS portion <NUM>, second gap portion <NUM>, and/or the first data portion <NUM> may be adjusted accordingly in the time and/or frequency domain. For example, a size of the first data portion <NUM> may be increased in the time and/or frequency domain, which may facilitate using a more reliable modulation and coding scheme to communicate data in the first portion <NUM>.

As described above, a wireless communication structure <NUM> for a NR D2D URLLC communication includes data associated with the D2D communication and also includes such data associated with the D2D communication re-transmitted in the wireless communication structure <NUM>. Such a blind retransmission of the data may reduce or avoid delay and/or control overhead of communicating acknowledgement information for each such data transmission. Such blind retransmission may facilitate or serve as open loop HARQ procedures or functionality. In aspects, when performing such a back-to-back transmission-retransmission (e.g., of the data in the wireless communication structure <NUM>), a same frequency resource may be employed for the data in the first mini-slot <NUM> and the re-transmitted data in the second mini-slot <NUM>. Alternatively, in aspects frequency hopping, for retransmission (e.g., of the data) in second mini-slot <NUM> may provide some advantage (e.g., diversity). In aspects, a frequency relationship between the first mini-slot <NUM> and second mini-slot <NUM> may be fixed and/or configured.

The transmitted data (e.g., in the first mini-slot <NUM>) and the re-transmitted data (e.g., in the second mini-slot <NUM>) may be independently decoded by the receiving UE <NUM>. Therefore, a latency may be reduced because the receiving UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> may decode first transmission (e.g., the data in the first mini-slot <NUM> without having to wait for retransmission (e.g., the re-transmitted data in the second mini-slot <NUM>). As shown, the second mini-slot <NUM> for the re-transmitted data does not include overhead such as the RTS portion <NUM>, the first gap portion <NUM>, the CTS portion <NUM>, the second gap portion <NUM>, and/or the control portion <NUM> of the first mini-slot <NUM>. Consequently, more resources are available in the second mini-slot <NUM> for the re-transmitted data, which may allow use of a reduced code rate (e.g., for the re-transmitted data) to increase reliability.

As described above, the wireless communication structure <NUM> includes an acknowledgment portion <NUM> to account for feedback (e.g., a NAK). Such NAK is sent in the wireless communication structure <NUM> sent by a UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> after a back-to-back transmission-retransmission of data of a previous wireless communication structure 601was received (e.g., unsuccessfully) by the UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM>. As described further with reference to <FIG>, after receiving a NAK associated with a previous NR D2D URLLC transmission by a UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM>, such UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> may re-transmit the NR D2D URLLC (e.g., again perform back-to-back transmission-retransmission of the data from a previous wireless communication structure <NUM>). Such feedback may facilitate closed loop HARQ procedures or functionality. In this manner the present methods and apparatus may effectively provide a design using open loop HARQ and closed loop HARQ.

Thus, a listen-before-talk (LBT) sequence may be employed, for example, before communicating data for NR D2D communication, such as a NR D2D normal communication, in a slot of a wireless communication structure <NUM>. However, in aspects, RTS and CTS signaling along with a communication of data in a first mini-slot <NUM>, and a communication of the data re-transmitted in a second mini-slot <NUM> of a wireless communication structure <NUM> may be employed for NR D2D communication, such as a NR D2D URLLC communication. In this manner, for such NR D2D URLLC communication a reliability is increased and/or latency is decreased (e.g., compared to TTI-based LBT communication mechanisms).

<FIG> is another diagram illustrating <NUM> NR D2D (e.g., V2V or V2X) URLLC communication <NUM> in accordance with various aspects of the present disclosure. For example, a UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> may communicate NR D2D URLLC communication <NUM>, such as NR D2D URLLC communication 609a, using wireless communication structure 601a as described above. A HARQ process allows multiple transmissions (e.g., including an initial transmission and one or more retransmissions) to enable a receiving UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> to decode a received packet of the transmissions. For example, the MAC layer may use HARQ to provide retransmission at the MAC layer to improve link efficiency. Accordingly, a HARQ process enables a certain data rate without perfect link adaptation. Should the UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> receive a NAK associated with the previous NR D2D URLLC communication <NUM>, in aspects, the UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> may retransmit the NR D2D URLLC communication. For example, the re-transmission <NUM> of the NR D2D URLLC communication may include control information indicating the previous NR D2D URLLC communication 609a. In aspects, the control information indicating the previous NR D2D URLLC communication 609a may be included in the control portion <NUM>. Similarly, if the UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> communicates an NR D2D URLLC communication using wireless communication structure 601b for which a NAK is received, a re-transmission of the NR D2D URLLC communication may include control information indicating the previous NR D2D URLLC communication 609a in the RTS portion <NUM>. Thus, a HARQ design for NR V2X URLLC may be provided. Data may be processed based on combining the retransmission of the communication and the previous communication. In this manner, if the data and re-transmitted data of a NR D2D URLLC communication <NUM> using wireless communication structure <NUM> is unsuccessfully communicated, the data and re-transmitted data may be included in a retransmission <NUM> of the NR D2D URLLC communication using wireless communication structure <NUM>.

<FIG> is a flow diagram of a method of NR D2D URLLC communication in accordance with various aspects of the present disclosure. Steps of the method <NUM> may be executed by a computing device (e.g., a processor, processing circuit, and/or other suitable component) of a wireless communication device, such as the UEs <NUM>, <NUM>', <NUM>, <NUM> and <NUM>. As illustrated, the method <NUM> of wireless communication includes a number of enumerated steps, but embodiments of the method <NUM> may include additional steps before, after, and in between the enumerated steps. In some embodiments, one or more of the enumerated steps may be omitted or performed in a different order.

At step <NUM>, the method <NUM> includes transmitting data associated with an ultra-reliable and low-latency communications (URLLC) communication in a first set of one or more portions of a wireless communication structure having a plurality of portions. At step <NUM>, the method <NUM> includes re-transmitting the data associated with the URLLC communication in a second set of one or more portions of the wireless communication structure, wherein one or more slot structures of the wireless communication structure are defined by the plurality of portions, the first set of one or more portions is based on a first mini-slot structure, the second set of one or more portions is based on a second mini-slot structure, and a mini-slot structure is smaller than a slot structure. In aspects, the first mini-slot structure and the second mini-slot structure are associated with the same frequency resources. In aspects, the first mini-slot structure and the second mini-slot structure are associated with different frequency resources. For example, in aspects, the second mini-slot <NUM> may be associated with or employ different frequency resources than the frequency resources associated with or employed by the first mini-slot <NUM>. In aspects, the method <NUM> may further comprise transmitting, in the first mini-slot structure, control information associated with at least one of the data in the first set or the data in the second set. In such aspects, the control information in the first mini-slot structure includes an indicator of a previous transmission, when the URLLC communication is a hybrid automatic repeat request retransmission. In such aspects, the method <NUM> may further comprise transmitting, in the second mini-slot structure, control information associated with the data in the second set. In such further aspects, the control information in the second mini-slot structure includes information indicating the data in the second set is the data re-transmitted.

In aspects, transmitting data associated the first set of one or more portions includes employing a first modulation and coding scheme providing a first redundancy, and re-transmitting the data in the second set of one or more portions includes employing a second modulation and coding scheme providing a second redundancy. In aspects, the second redundancy is greater than the first redundancy. In aspects, the method <NUM> may further comprise receiving, in the second mini-slot structure, an acknowledgement message associated with a transmission by the UE in at least one of a previous mini-slot structure, slot structure, or wireless communication structure. In aspects, the second mini-slot structure accounts for an acknowledgement message and the first mini-slot structure does not account for an acknowledgement message. In aspects, the mini-slot structure is aligned with a boundary of a portion. In aspects, the wireless communication structure includes one or more wireless communication subframes. In aspects, each portion of the plurality of portions is associated with a respective symbol. In aspects, the second set of one or more portions are subsequent the first set of one or more portions. In such aspects, the second set of one or more portions succeed the first set of one or more portions. In aspects, transmitting and re-transmitting include at least one of multi-casting, unicasting or broadcasting. In aspects, the method <NUM> may further comprise transmitting a non-URLLC communication in a slot structure of the wireless communication structure. In aspects, the method <NUM> may further comprise determining at least one of a mini-slot structure or a slot structure associated with the wireless communication structure based on a configuration, signaling or a combination thereof. In this manner, a reliability is increased and/or latency is decreased for a NR D2D communication, such as a NR D2D URLLC communication (e.g., compared to TTI-based LBT communication mechanisms).

<FIG> is a flow diagram of another method of NR D2D URLLC communication in accordance with various aspects of the present disclosure. Steps of the method <NUM> may be executed by a computing device (e.g., a processor, processing circuit, and/or other suitable component) of a wireless communication device, such as the UEs <NUM>, <NUM>', <NUM>, <NUM> and <NUM>. As illustrated, the method <NUM> of wireless communication includes a number of enumerated steps, but embodiments of the method <NUM> may include additional steps before, after, and in between the enumerated steps. In some embodiments, one or more of the enumerated steps may be omitted or performed in a different order.

At step <NUM>, the method <NUM> includes receiving data associated with an ultra-reliable and low-latency communications (URLLC) communication in a first set of one or more portions of a wireless communication structure having a plurality of portions. At step <NUM>, the method <NUM> includes receiving the data associated with the URLLC communication re-transmitted in a second set of one or more portions of the wireless communication structure, wherein one or more slot structures of the wireless communication structure are defined by the plurality of portions, the first set of one or more portions is based on a first mini-slot structure, the second set of one or more portions is based on a second mini-slot structure, and a mini-slot structure is smaller than a slot structure. In aspects, the first mini-slot structure and the second mini-slot structure are associated with the same frequency resources. In aspects, the first mini-slot structure and the second mini-slot structure are associated with different frequency resources. For example, in aspects, the second mini-slot <NUM> may be associated with or employ different frequency resources than the frequency resources associated with or employed by the first mini-slot <NUM>. In aspects, the method <NUM> may further comprise receiving, in the first mini-slot structure, control information associated with at least one of the data in the first set or the data in the second set. In such aspects, the control information in the first mini-slot structure includes an indicator of a previous URLLC communication, when the URLLC communication is a hybrid automatic repeat request retransmission. In such further aspects, the method <NUM> further comprises processing data based on combining the hybrid automatic repeat request retransmission and the previous URLLC communication.

In aspects, the method <NUM> may further comprise receiving, in the second mini-slot structure, control information associated with the data in the second set. In such aspects, the control information in the second mini-slot structure includes information indicating the data in the second set is the data re-transmitted. In aspects, receiving data associated the first set of one or more portions includes processing the data based on a first modulation and coding scheme providing a first redundancy, and receiving data re-transmitted in the second set of one or more portions includes processing the data based on a second modulation and coding scheme providing a second redundancy. In aspects, the method <NUM> may further comprise transmitting, in the second mini-slot structure, an acknowledgement message associated with a transmission by another network entity in at least one of a previous mini-slot structure, slot structure, or wireless communication structure. In aspects, the second mini-slot structure accounts for an acknowledgement message and the first mini-slot structure does not account for an acknowledgement message. In aspects, the mini-slot structure is aligned with a boundary of a portion. In aspects, the wireless communication structure includes one or more wireless communication subframes. In aspects, each portion of the plurality of portions is associated with a respective symbol. In aspects, the second set of one or more portions are subsequent the first set of one or more portions. In such aspects, the second set of one or more portions succeed the first set of one or more portions.

In aspects, the method <NUM> may further comprise decoding the data based on at least one of the first set of one or more portions or the second set of one or more portions. In aspects, the method <NUM> may further comprise receiving a non-URLLC communication in a slot structure of the wireless communication structure. In aspects, the method <NUM> may further comprise determining at least one of a mini-slot structure or a slot structure associated with the wireless communication structure based on a configuration, signaling or a combination thereof. In this manner, a reliability is increased and/or latency is decreased for a NR D2D communication, such as a NR D2D URLLC communication (e.g., compared to TTI-based LBT communication mechanisms).

<FIG> is a block diagram of an exemplary user equipment (UE) in accordance with aspects of the present disclosure. In aspects, the UE <NUM> may be a UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM>, as discussed above, for example. As shown, the UE <NUM> may include a processor <NUM>, a memory <NUM>, transmitting data associated with a URLLC communication in a first set of one or more portions of a wireless communication structure module <NUM>, a re-transmitting the data associated with the URLLC communication in a second set of one or more portions of the wireless communication structure module <NUM>, a transceiver <NUM> including a modem subsystem <NUM> and a radio frequency (RF) unit <NUM>, and one or more antennas <NUM>. These elements may be in direct or indirect communication with each other, for example via one or more buses.

The processor <NUM> may include a central processing unit (CPU), a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a controller, a field programmable gate array (FPGA) device, another hardware device, a firmware device, or any combination thereof configured to perform the operations described herein.

The memory <NUM> may include a cache memory (e.g., a cache memory of the processor <NUM>), random access memory (RAM), magnetoresistive RAM (MRAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read only memory (EPROM), electrically erasable programmable read only memory (EEPROM), flash memory, solid state memory device, hard disk drives, other forms of volatile and non-volatile memory, or a combination of different types of memory. In an embodiment, the memory <NUM> includes a non-transitory computer-readable medium. The instructions <NUM> may include instructions that, when executed by the processor <NUM>, cause the processor <NUM> to perform the operations, such as operations <NUM> and/or operations <NUM>, described herein with reference to one or more of the UEs <NUM>, <NUM>', <NUM>, <NUM> and <NUM> in connection with embodiments of the present disclosure. Instructions <NUM> may also be referred to as code. The terms "instructions" and "code" should be interpreted broadly to include any type of computer-readable statement(s). For example, the terms "instructions" and "code" may refer to one or more programs, routines, sub-routines, functions, procedures, etc. "Instructions" and "code" may include a single computer-readable statement or many computer-readable statements.

The transmitting data associated with a URLLC communication in a first set of one or more portions of a wireless communication structure module <NUM> and/or the re-transmitting the data associated with the URLLC communication in a second set of one or more portions of the wireless communication structure module <NUM> may be used for various aspects of the present disclosure. For example, the transmitting data associated with a URLLC communication in a first set of one or more portions of a wireless communication structure module <NUM> may transmit data associated with a URLLC communication in a first set of one or more portions of a wireless communication structure having a plurality of portions, and the re-transmitting the data associated with the URLLC communication in a second set of one or more portions of the wireless communication structure module <NUM> may re-transmit the data associated with the URLLC communication in a second set of one or more portions of the wireless communication structure, wherein one or more slot structures of the wireless communication structure are defined by the plurality of portions, the first set of one or more portions is based on a first mini-slot structure, the second set of one or more portions is based on a second mini-slot structure, and a mini-slot structure is smaller than a slot structure.

As shown, the transceiver <NUM> may include the modem subsystem <NUM> and the RF unit <NUM>. The transceiver <NUM> may be configured to communicate bi-directionally with other devices, such as the BSs <NUM> or other UEs <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM>. The modem subsystem <NUM> may be configured to modulate and/or encode the data from the memory <NUM>, transmitting data associated with a URLLC communication in a first set of one or more portions of a wireless communication structure module <NUM>, and/or the re-transmitting the data associated with the URLLC communication in a second set of one or more portions of the wireless communication structure module <NUM> according to a modulation and coding scheme (MCS), e.g., a low-density parity check (LDPC) coding scheme, a turbo coding scheme, a convolutional coding scheme, a digital beamforming scheme, etc. The RF unit <NUM> may be configured to process (e.g., perform analog to digital conversion or digital to analog conversion, etc.) modulated/encoded data from the modem subsystem <NUM> (on outbound transmissions) or of transmissions originating from another source such as another UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> or a BS <NUM>. The RF unit <NUM> may be further configured to perform analog beamforming in conjunction with the digital beamforming. Although shown as integrated together in transceiver <NUM>, the modem subsystem <NUM> and the RF unit <NUM> may be separate devices that are coupled together at the UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> to enable the UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> to communicate with other devices.

The RF unit <NUM> may provide the modulated and/or processed data, e.g. data packets (or, more generally, data messages that may contain one or more data packets and other information), to the antennas <NUM> for transmission to one or more other devices. This may include, for example, transmission of non-URLLC communication (e.g., NR D2D normal communication) and/or URLLC communication (e.g., NR D2D URLLC communication), according to embodiments of the present disclosure. The antennas <NUM> may further receive data messages transmitted from other devices. This may include, for example, receiving non-URLLC communication (e.g., NR D2D normal communication) and/or receiving URLLC communication (e.g., NR D2D URLLC communication), according to embodiments of the present disclosure. The antennas <NUM> may provide the received data messages for processing and/or demodulation at the transceiver <NUM>. The antennas <NUM> may include multiple antennas of similar or different designs in order to sustain multiple transmission links. The RF unit <NUM> may configure the antennas <NUM>. In aspects, one or more of any of the components of the UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> may perform NR D2D URLLC communication as described herein.

Other examples are possible and may differ from what was described in connection with <FIG>.

<FIG> is another block diagram of an exemplary user equipment (UE) in accordance with aspects of the present disclosure. In aspects, the UE <NUM> may be a UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM>, as discussed above, for example. As shown, the UE <NUM> may include a processor <NUM>, a memory <NUM>, a receiving data associated with a URLLC communication in a first set of one or more portions of a wireless communication structure module <NUM>, a receiving the data associated with the URLLC communication re-transmitted in a second set of one or more portions of the wireless communication structure module <NUM>, a transceiver <NUM> including a modem subsystem <NUM> and a radio frequency (RF) unit <NUM>, and one or more antennas <NUM>. These elements may be in direct or indirect communication with each other, for example via one or more buses.

The receiving data associated with a URLLC communication in a first set of one or more portions of a wireless communication structure module <NUM> and the receiving the data associated with the URLLC communication re-transmitted in a second set of one or more portions of the wireless communication structure module <NUM> may be used for various aspects of the present disclosure. For example, the receiving data associated with a URLLC communication in a first set of one or more portions of a wireless communication structure module <NUM> may receive data associated with a URLLC communication in a first set of one or more portions of a wireless communication structure having a plurality of portions, and the receiving the data associated with the URLLC communication re-transmitted in a second set of one or more portions of the wireless communication structure module <NUM> may receive the data associated with the URLLC communication re-transmitted in a second set of one or more portions of the wireless communication structure, wherein one or more slot structures of the wireless communication structure are defined by the plurality of portions, the first set of one or more portions is based on a first mini-slot structure, the second set of one or more portions is based on a second mini-slot structure, and a mini-slot structure is smaller than a slot structure.

As shown, the transceiver <NUM> may include the modem subsystem <NUM> and the RF unit <NUM>. The transceiver <NUM> may be configured to communicate bi-directionally with other devices, such as the BSs <NUM> or other UEs <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM>. The modem subsystem <NUM> may be configured to modulate and/or encode the data from the memory <NUM>, the receiving data associated with a URLLC communication in a first set of one or more portions of a wireless communication structure module <NUM>, and/or the communicating based on the adjusted wireless communication structure module <NUM> according to a modulation and coding scheme (MCS), e.g., a low-density parity check (LDPC) coding scheme, a turbo coding scheme, a convolutional coding scheme, a digital beamforming scheme, etc. The RF unit <NUM> may be configured to process (e.g., perform analog to digital conversion or digital to analog conversion, etc.) modulated/encoded data from the modem subsystem <NUM> (on outbound transmissions) or of transmissions originating from another source such as another UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> or a BS <NUM>. The RF unit <NUM> may be further configured to perform analog beamforming in conjunction with the digital beamforming. Although shown as integrated together in transceiver <NUM>, the modem subsystem <NUM> and the RF unit <NUM> may be separate devices that are coupled together at the UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> to enable the UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> to communicate with other devices.

The RF unit <NUM> may provide the modulated and/or processed data, e.g. data packets (or, more generally, data messages that may contain one or more data packets and other information), to the antennas <NUM> for transmission to one or more other devices. This may include, for example, transmission of non-URLLC communication (e.g., NR D2D normal communication) and/or URLLC communication (e.g., NR D2D URLLC communication), according to embodiments of the present disclosure. The antennas <NUM> may further receive data messages and/or NR D2D URLLC communication transmitted from other devices. This may include, for example, receiving non-URLLC communication (e.g., NRD2D normal communication) and/or receiving URLLC communication (e.g., NR D2D URLLC communication), according to embodiments of the present disclosure. The antennas <NUM> may provide the received data messages for processing and/or demodulation at the transceiver <NUM>. The antennas <NUM> may include multiple antennas of similar or different designs in order to sustain multiple transmission links. The RF unit <NUM> may configure the antennas <NUM>. In aspects, one or more of any of the components of the UE <NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM> may perform NR D2D URLLC communication as described herein.

It is understood that included herein are some example claim elements. For example, the wireless communication structure includes one or more wireless communication subframes; wherein the mini-slot structure is aligned with a boundary of a portion; wherein each portion of the plurality of portions is associated with a respective symbol. The second set of one or more portions succeed the first set of one or more portions. Transmitting and re-transmitting data include at least one of multi-casting, unicasting or broadcasting. Each portion of the plurality of portions is associated with a respective symbol.

Claim 1:
A method of wireless communication by a user equipment, UE, comprising:
transmitting data associated with an ultra-reliable and low-latency communications, URLLC, communication in a vehicle-to-everything, V2X, environment in a first set of one or more portions of a wireless communication structure (<NUM>, <NUM>) having a plurality of portions; and
re-transmitting (<NUM>) the data associated with the URLLC communication in a second set of one or more portions of the wireless communication structure blindly without waiting for a feedback from a receiver,
wherein one or more slot structures of the wireless communication structure are defined by the plurality of portions, the first set of one or more portions is based on a first mini-slot structure (<NUM>), the second set of one or more portions is based on a second mini-slot structure (<NUM>), and a mini-slot structure is smaller than a slot structure (<NUM>);
wherein the transmitted data and the re-transmitted data are transmitted back-to-back in the wireless communication structure.