Patent Publication Number: US-2023155725-A1

Title: Radio link control layer feedback reporting for rateless codes

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This Patent Application claims priority to International Patent Application No. PCT/CN2020/093858, filed on Jun. 2, 2020, entitled “RADIO LINK CONTROL LAYER FEEDBACK REPORTING FOR RATELESS CODES,” and assigned to the assignee hereof. The disclosure of the prior Application is considered part of and is incorporated by reference into this Patent Application. 
    
    
     FIELD OF THE DISCLOSURE 
     Aspects of the present disclosure generally relate to wireless communication and to techniques and apparatuses for radio link control layer feedback reporting for rateless codes. 
     BACKGROUND 
     Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. Typical wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, or the like). Examples of such multiple-access technologies include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency-division multiple access (FDMA) systems, orthogonal frequency-division multiple access (OFDMA) systems, single-carrier frequency-division multiple access (SC-FDMA) systems, time division synchronous code division multiple access (TD-SCDMA) systems, and Long Term Evolution (LTE). LTE/LTE-Advanced is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by the Third Generation Partnership Project (3GPP). 
     A wireless network may include a number of base stations (BSs) that can support communication for a number of user equipment (UEs). A UE may communicate with a BS via the downlink and uplink. “Downlink” (or “forward link”) refers to the communication link from the BS to the UE, and “uplink” (or “reverse link”) refers to the communication link from the UE to the BS. As will be described in more detail herein, a BS may be referred to as a Node B, a gNB, an access point (AP), a radio head, a transmit receive point (TRP), a New Radio (NR) BS, a 5G Node B, or the like. 
     The above multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different user equipment to communicate on a municipal, national, regional, and even global level. NR, which may also be referred to as 5G, is a set of enhancements to the LTE mobile standard promulgated by the 3GPP. NR is designed to better support mobile broadband Internet access by improving spectral efficiency, lowering costs, improving services, making use of new spectrum, and better integrating with other open standards using orthogonal frequency division multiplexing (OFDM) with a cyclic prefix (CP) (CP-OFDM) on the downlink (DL), using CP-OFDM and/or SC-FDM (e.g., also known as discrete Fourier transform spread OFDM (DFT-s-OFDM)) on the uplink (UL), as well as supporting beamforming, multiple-input multiple-output (MIMO) antenna technology, and carrier aggregation. As the demand for mobile broadband access continues to increase, further improvements in LTE, NR, and other radio access technologies remain useful. 
     SUMMARY 
     In some aspects, a method of wireless communication performed by a receiver includes determining that a quantity of a first plurality of radio link layer (RLC) protocol data unit (PDU) packets, received from a transmitter, satisfies a first quantity threshold; performing a decoding attempt for the first plurality of RLC PDU packets based at least in part on determining that the quantity of the first plurality of RLC PDU packets satisfies the first quantity threshold; and transmitting, to the transmitter, an RLC layer feedback report for the first plurality of RLC PDU packets after receiving a second plurality of RLC PDU packets from the transmitter, wherein the second plurality of RLC PDU packets are received after the first plurality of RLC PDU packets, and wherein the RLC layer feedback report is based at least in part on the decoding attempt. 
     In some aspects, a non-transitory computer-readable medium storing a set of instructions for wireless communication includes one or more instructions that, when executed by one or more processors of a receiver, cause the receiver to determine that a quantity of a first plurality of RLC PDU packets, received from a transmitter, satisfies a first quantity threshold; perform a decoding attempt for the first plurality of RLC PDU packets based at least in part on determining that the quantity of the first plurality of RLC PDU packets satisfies the first quantity threshold; and transmit, to the transmitter, an RLC layer feedback report for the first plurality of RLC PDU packets after receiving a second plurality of RLC PDU packets from the transmitter, wherein the second plurality of RLC PDU packets are received after the first plurality of RLC PDU packets, and wherein the RLC layer feedback report is based at least in part on the decoding attempt. 
     In some aspects, a receiver for wireless communication includes a memory; and one or more processors coupled with the memory, the memory and the one or more processors configured to determine that a quantity of a first plurality of RLC PDU packets, received from a transmitter, satisfies a first quantity threshold; perform a decoding attempt for the first plurality of RLC PDU packets based at least in part on determining that the quantity of the first plurality of RLC PDU packets satisfies the first quantity threshold; and transmit, to the transmitter, an RLC layer feedback report for the first plurality of RLC PDU packets after receiving a second plurality of RLC PDU packets from the transmitter, wherein the second plurality of RLC PDU packets are received after the first plurality of RLC PDU packets, and wherein the RLC layer feedback report is based at least in part on the decoding attempt. 
     In some aspects, an apparatus for wireless communication includes means for determining that a quantity of a first plurality of RLC PDU packets, received from a transmitter, satisfies a first quantity threshold; means for performing a decoding attempt for the first plurality of RLC PDU packets based at least in part on determining that the quantity of the first plurality of RLC PDU packets satisfies the first quantity threshold; and means for transmitting, to the transmitter, an RLC layer feedback report for the first plurality of RLC PDU packets after receiving a second plurality of RLC PDU packets from the transmitter, wherein the second plurality of RLC PDU packets are received after the first plurality of RLC PDU packets, and wherein the RLC layer feedback report is based at least in part on the decoding attempt. 
     In some aspects, a method of wireless communication performed by a receiver includes determining that an RLC PDU packet having a particular packet SN was received from a transmitter, and performing, based at least in part on determining that the RLC PDU packet having the particular packet SN was received, a decoding attempt for a plurality of RLC PDU packets that were received from the transmitter, wherein the plurality of RLC PDU packets have packet SNs lower than the particular packet SN of the RLC PDU packet. 
     In some aspects, a non-transitory computer-readable medium storing a set of instructions for wireless communication includes one or more instructions that, when executed by one or more processors of a receiver, cause the receiver to determine that an RLC PDU packet having a particular packet SN was received from a transmitter, and perform, based at least in part on determining that the RLC PDU packet having the particular packet SN was received, a decoding attempt for a plurality of RLC PDU packets that were received from the transmitter, wherein the plurality of RLC PDU packets have packet SNs lower than the particular packet SN of the RLC PDU packet. 
     In some aspects, a receiver for wireless communication includes a memory, and one or more processors coupled with the memory, the memory and the one or more processors configured to determine that an RLC PDU packet having a particular packet SN was received from a transmitter, and perform, based at least in part on determining that the RLC PDU packet having the particular packet SN was received, a decoding attempt for a plurality of RLC PDU packets that were received from the transmitter, wherein the plurality of RLC PDU packets have packet SNs lower than the particular packet SN of the RLC PDU packet. 
     In some aspects, an apparatus for wireless communication includes means for determining that an RLC PDU packet having a particular packet SN was received from a transmitter, and means for performing, based at least in part on determining that the RLC PDU packet having the particular packet SN was received, a decoding attempt for a plurality of RLC PDU packets that were received from the transmitter, wherein the plurality of RLC PDU packets have packet SNs lower than the particular packet SN of the RLC PDU packet. 
     Aspects generally include a method, apparatus, system, computer program product, non-transitory computer-readable medium, user equipment, base station, wireless communication device, and/or processing system as substantially described herein with reference to and as illustrated by the drawings and specification. 
     The foregoing has outlined rather broadly the features and technical advantages of examples according to the disclosure in order that the detailed description that follows may be better understood. Additional features and advantages will be described hereinafter. The conception and specific examples disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. Such equivalent constructions do not depart from the scope of the appended claims. Characteristics of the concepts disclosed herein, both their organization and method of operation, together with associated advantages will be better understood from the following description when considered in connection with the accompanying figures. Each of the figures is provided for the purposes of illustration and description, and not as a definition of the limits of the claims. 
     While aspects are described in the present disclosure by illustration to some examples, those skilled in the art will understand that such aspects may be implemented in many different arrangements and scenarios. Techniques described herein may be implemented using different platform types, devices, systems, shapes, sizes, and/or packaging arrangements. For example, some aspects may be implemented via integrated chip embodiments or other non-module-component based devices (e.g., end-user devices, vehicles, communication devices, computing devices, industrial equipment, retail/purchasing devices, medical devices, or artificial intelligence-enabled devices). Aspects may be implemented in chip-level components, modular components, non-modular components, non-chip-level components, device-level components, or system-level components. Devices incorporating described aspects and features may include additional components and features for implementation and practice of claimed and described aspects. For example, transmission and reception of wireless signals may include a number of components for analog and digital purposes (e.g., hardware components including antennas, RF chains, power amplifiers, modulators, buffers, processor(s), interleavers, adders, or summers). It is intended that aspects described herein may be practiced in a wide variety of devices, components, systems, distributed arrangements, or end-user devices of varying size, shape, and constitution. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       So that the above-recited features of the present disclosure can be understood in detail, a more particular description, briefly summarized above, may be had by reference to aspects, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only certain typical aspects of this disclosure and are therefore not to be considered limiting of its scope, for the description may admit to other equally effective aspects. The same reference numbers in different drawings may identify the same or similar elements. 
         FIG.  1    is a diagram illustrating an example of a wireless network, in accordance with the present disclosure. 
         FIG.  2    is a diagram illustrating an example of a base station in communication with a UE in a wireless network, in accordance with the present disclosure. 
         FIG.  3    illustrates an example logical architecture of a distributed radio access network (RAN), in accordance with the present disclosure. 
         FIG.  4    illustrates an example physical architecture of a distributed RAN, in accordance with the present disclosure. 
         FIG.  5    is a diagram illustrating an example of network coding, in accordance with the present disclosure. 
         FIGS.  6 A and  6 B  are diagrams illustrating examples associated with radio link control layer (RLC) feedback reporting for rateless codes, in accordance with the present disclosure. 
         FIGS.  7  and  8    are diagrams illustrating example processes associated with RLC feedback reporting for rateless codes, in accordance with the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Various aspects of the disclosure are described more fully hereinafter with reference to the accompanying drawings. This disclosure may, however, be embodied in many different forms and should not be construed as limited to any specific structure or function presented throughout this disclosure. Rather, these aspects are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. Based on the teachings herein, one skilled in the art should appreciate that the scope of the disclosure is intended to cover any aspect of the disclosure disclosed herein, whether implemented independently of or combined with any other aspect of the disclosure. For example, an apparatus may be implemented or a method may be practiced using any number of the aspects set forth herein. In addition, the scope of the disclosure is intended to cover such an apparatus or method which is practiced using other structure, functionality, or structure and functionality in addition to or other than the various aspects of the disclosure set forth herein. It should be understood that any aspect of the disclosure disclosed herein may be embodied by one or more elements of a claim. 
     Several aspects of telecommunication systems will now be presented with reference to various apparatuses and techniques. These apparatuses and techniques will be described in the following detailed description and illustrated in the accompanying drawings by various blocks, modules, components, circuits, steps, processes, algorithms, or the like (collectively referred to as “elements”). These elements may be implemented using hardware, software, or combinations thereof. Whether such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. 
     It should be noted that while aspects may be described herein using terminology commonly associated with a 5G or NR radio access technology (RAT), aspects of the present disclosure can be applied to other RATs, such as a 3G RAT, a 4G RAT, and/or a RAT subsequent to 5G (e.g., 6G). 
       FIG.  1    is a diagram illustrating an example of a wireless network  100 , in accordance with the present disclosure. The wireless network  100  may be or may include elements of a 5G (NR) network and/or an LTE network, among other examples. The wireless network  100  may include a number of base stations  110  (shown as BS  110   a , BS  110   b , BS  110   c , and BS  110   d ) and other network entities. A base station (BS) is an entity that communicates with user equipment (UEs) and may also be referred to as an NR BS, a Node B, a gNB, a 5G node B (NB), an access point, a transmit receive point (TRP), or the like. Each BS may provide communication coverage for a particular geographic area. In 3GPP, the term “cell” can refer to a coverage area of a BS and/or a BS subsystem serving this coverage area, depending on the context in which the term is used. 
     A BS may provide communication coverage for a macro cell, a pico cell, a femto cell, and/or another type of cell. A macro cell may cover a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by UEs with service subscription. A pico cell may cover a relatively small geographic area and may allow unrestricted access by UEs with service subscription. A femto cell may cover a relatively small geographic area (e.g., a home) and may allow restricted access by UEs having association with the femto cell (e.g., UEs in a closed subscriber group (CSG)). A BS for a macro cell may be referred to as a macro BS. A BS for a pico cell may be referred to as a pico BS. A BS for a femto cell may be referred to as a femto BS or a home BS. In the example shown in  FIG.  1   , a BS  110   a  may be a macro BS for a macro cell  102   a , a BS  110   b  may be a pico BS for a pico cell  102   b , and a BS  110   c  may be a femto BS for a femto cell  102   c . A BS may support one or multiple (e.g., three) cells. The terms “eNB”, “base station”, “NR BS”, “gNB”, “TRP”, “AP”, “node B”, “5G NB”, and “cell” may be used interchangeably herein. 
     In some aspects, a cell may not necessarily be stationary, and the geographic area of the cell may move according to the location of a mobile BS. In some aspects, the BSs may be interconnected to one another and/or to one or more other BSs or network nodes (not shown) in the wireless network  100  through various types of backhaul interfaces, such as a direct physical connection or a virtual network, using any suitable transport network. 
     Wireless network  100  may also include relay stations. A relay station is an entity that can receive a transmission of data from an upstream station (e.g., a BS or a UE) and send a transmission of the data to a downstream station (e.g., a UE or a BS). A relay station may also be a UE that can relay transmissions for other UEs. In the example shown in  FIG.  1   , a relay BS  110   d  may communicate with macro BS  110   a  and a UE  120   d  in order to facilitate communication between BS  110   a  and UE  120   d . A relay BS may also be referred to as a relay station, a relay base station, a relay, or the like. 
     Wireless network  100  may be a heterogeneous network that includes BSs of different types, such as macro BSs, pico BSs, femto BSs, relay BSs, or the like. These different types of BSs may have different transmit power levels, different coverage areas, and different impacts on interference in wireless network  100 . For example, macro BSs may have a high transmit power level (e.g., 5 to 40 watts) whereas pico BSs, femto BSs, and relay BSs may have lower transmit power levels (e.g., 0.1 to 2 watts). 
     A network controller  130  may couple to a set of BSs and may provide coordination and control for these BSs. Network controller  130  may communicate with the BSs via a backhaul. The BSs may also communicate with one another, directly or indirectly, via a wireless or wireline backhaul. 
     UEs  120  (e.g.,  120   a ,  120   b ,  120   c ) may be dispersed throughout wireless network  100 , and each UE may be stationary or mobile. A UE may also be referred to as an access terminal, a terminal, a mobile station, a subscriber unit, a station, or the like. A UE may be a cellular phone (e.g., a smart phone), a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a tablet, a camera, a gaming device, a netbook, a smartbook, an ultrabook, a medical device or equipment, biometric sensors/devices, wearable devices (smart watches, smart clothing, smart glasses, smart wrist bands, smart jewelry (e.g., smart ring, smart bracelet)), an entertainment device (e.g., a music or video device, or a satellite radio), 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. 
     Some UEs may be considered machine-type communication (MTC) or evolved or enhanced machine-type communication (eMTC) UEs. MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, and/or location tags, that may communicate with a base station, another device (e.g., remote device), or some other entity. A wireless node may provide, for example, connectivity for or to a network (e.g., a wide area network such as Internet or a cellular network) via a wired or wireless communication link. Some UEs may be considered Internet-of-Things (IoT) devices, and/or may be implemented as NB-IoT (narrowband internet of things) devices. Some UEs may be considered a Customer Premises Equipment (CPE). UE  120  may be included inside a housing that houses components of UE  120 , such as processor components and/or memory components. In some aspects, the processor components and the memory components may be coupled together. For example, the processor components (e.g., one or more processors) and the memory components (e.g., a memory) may be operatively coupled, communicatively coupled, electronically coupled, and/or electrically coupled. 
     In general, any number of wireless networks may be deployed in a given geographic area. Each wireless network may support a particular RAT and may operate on one or more frequencies. A RAT may also be referred to as a radio technology, an air interface, or the like. A frequency may also be referred to as a carrier, a frequency channel, or the like. Each frequency may support a single RAT in a given geographic area in order to avoid interference between wireless networks of different RATs. In some cases, NR or 5G RAT networks may be deployed. 
     In some aspects, two or more UEs  120  (e.g., shown as UE  120   a  and UE  120   e ) may communicate directly using one or more sidelink channels (e.g., without using a base station  110  as an intermediary to communicate with one another). For example, the UEs  120  may communicate using peer-to-peer (P2P) communications, device-to-device (D2D) communications, a vehicle-to-everything (V2X) protocol (e.g., which may include a vehicle-to-vehicle (V2V) protocol or a vehicle-to-infrastructure (V2I) protocol), and/or a mesh network. In this case, the UE  120  may perform scheduling operations, resource selection operations, and/or other operations described elsewhere herein as being performed by the base station  110 . 
     Devices of wireless network  100  may communicate using the electromagnetic spectrum, which may be subdivided based on frequency or wavelength into various classes, bands, channels, or the like. For example, devices of wireless network  100  may communicate using an operating band having a first frequency range (FR 1 ), which may span from 410 MHz to 7.125 GHz, and/or may communicate using an operating band having a second frequency range (FR 2 ), which may span from 24.25 GHz to 52.6 GHz. The frequencies between FR 1  and FR 2  are sometimes referred to as mid-band frequencies. Although a portion of FR 1  is greater than 6 GHz, FR 1  is often referred to as a “sub-6 GHz” band. Similarly, FR 2  is often referred to as a “millimeter wave” band despite being different from the extremely high frequency (EHF) band (30 GHz - 300 GHz) which is identified by the International Telecommunications Union (ITU) as a “millimeter wave” band. Thus, unless specifically stated otherwise, it should be understood that the term “sub-6 GHz” or the like, if used herein, may broadly represent frequencies less than 6 GHz, frequencies within FR 1 , and/or mid-band frequencies (e.g., greater than 7.125 GHz). Similarly, unless specifically stated otherwise, it should be understood that the term “millimeter wave” or the like, if used herein, may broadly represent frequencies within the EHF band, frequencies within FR 2 , and/or mid-band frequencies (e.g., less than 24.25 GHz). It is contemplated that the frequencies included in FR 1  and FR 2  may be modified, and techniques described herein are applicable to those modified frequency ranges. 
     As indicated above,  FIG.  1    is provided as an example. Other examples may differ from what is described with regard to  FIG.  1   . 
       FIG.  2    is a diagram illustrating an example  200  of a base station  110  in communication with a UE  120  in a wireless network  100 , in accordance with the present disclosure. Base station  110  may be equipped with T antennas  234   a  through  234   t , and UE  120  may be equipped with R antennas  252   a  through  252   r , where in general T ≥ 1 and R ≥ 1. 
     At base station  110 , a transmit processor  220  may receive data from a data source  212  for one or more UEs, select one or more modulation and coding schemes (MCS) for each UE based at least in part on channel quality indicators (CQIs) received from the UE, process (e.g., encode and modulate) the data for each UE based at least in part on the MCS(s) selected for the UE, and provide data symbols for all UEs. Transmit processor  220  may also process system information (e.g., for semi-static resource partitioning information (SRPI)) and control information (e.g., CQI requests, grants, and/or upper layer signaling) and provide overhead symbols and control symbols. Transmit processor  220  may also generate reference symbols for reference signals (e.g., a cell-specific reference signal (CRS) or a demodulation reference signal (DMRS)) and synchronization signals (e.g., a primary synchronization signal (PSS) or a secondary synchronization signal (SSS)). A transmit (TX) multiple-input multiple-output (MIMO) processor  230  may perform spatial processing (e.g., precoding) on the data symbols, the control symbols, the overhead symbols, and/or the reference symbols, if applicable, and may provide T output symbol streams to T modulators (MODs)  232   a  through  232   t . Each modulator  232  may process a respective output symbol stream (e.g., for OFDM) to obtain an output sample stream. Each modulator  232  may further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. T downlink signals from modulators  232   a  through  232   t  may be transmitted via T antennas  234   a  through  234   t , respectively. 
     At UE  120 , antennas  252   a  through  252   r  may receive the downlink signals from base station  110  and/or other base stations and may provide received signals to demodulators (DEMODs)  254   a  through  254   r , respectively. Each demodulator  254  may condition (e.g., filter, amplify, downconvert, and digitize) a received signal to obtain input samples. Each demodulator  254  may further process the input samples (e.g., for OFDM) to obtain received symbols. A MIMO detector  256  may obtain received symbols from all R demodulators  254   a  through  254   r , perform MIMO detection on the received symbols if applicable, and provide detected symbols. A receive processor  258  may process (e.g., demodulate and decode) the detected symbols, provide decoded data for UE  120  to a data sink  260 , and provide decoded control information and system information to a controller/processor  280 . The term “controller/processor” may refer to one or more controllers, one or more processors, or a combination thereof. A channel processor may determine a reference signal received power (RSRP) parameter, a received signal strength indicator (RSSI) parameter, a reference signal received quality (RSRQ) parameter, and/or a channel quality indicator (CQI) parameter, among other examples. In some aspects, one or more components of UE  120  may be included in a housing  284 . 
     Network controller  130  may include communication unit  294 , controller/processor  290 , and memory  292 . Network controller  130  may include, for example, one or more devices in a core network. Network controller  130  may communicate with base station  110  via communication unit  294 . 
     Antennas (e.g., antennas  234   a  through  234   t  and/or antennas  252   a  through  252   r ) may include, or may be included within, one or more antenna panels, antenna groups, sets of antenna elements, and/or antenna arrays, among other examples. An antenna panel, an antenna group, a set of antenna elements, and/or an antenna array may include one or more antenna elements. An antenna panel, an antenna group, a set of antenna elements, and/or an antenna array may include a set of coplanar antenna elements and/or a set of non-coplanar antenna elements. An antenna panel, an antenna group, a set of antenna elements, and/or an antenna array may include antenna elements within a single housing and/or antenna elements within multiple housings. An antenna panel, an antenna group, a set of antenna elements, and/or an antenna array may include one or more antenna elements coupled to one or more transmission and/or reception components, such as one or more components of  FIG.  2   . 
     On the uplink, at UE  120 , a transmit processor  264  may receive and process data from a data source  262  and control information (e.g., for reports that include RSRP, RSSI, RSRQ, and/or CQI) from controller/processor  280 . Transmit processor  264  may also generate reference symbols for one or more reference signals. The symbols from transmit processor  264  may be precoded by a TX MIMO processor  266  if applicable, further processed by modulators  254   a  through  254   r  (e.g., for DFT-s-OFDM or CP-OFDM), and transmitted to base station  110 . In some aspects, a modulator and a demodulator (e.g., MOD/DEMOD  254 ) of the UE  120  may be included in a modem of the UE  120 . In some aspects, the UE  120  includes a transceiver. The transceiver may include any combination of antenna(s)  252 , modulators and/or demodulators  254 , MIMO detector  256 , receive processor  258 , transmit processor  264 , and/or TX MIMO processor  266 . The transceiver may be used by a processor (e.g., controller/processor  280 ) and memory  282  to perform aspects of any of the methods described herein (for example, as described with reference to  FIGS.  6 A,  6 B, and  7   ). 
     At base station  110 , the uplink signals from UE  120  and other UEs may be received by antennas  234 , processed by demodulators  232 , detected by a MIMO detector  236  if applicable, and further processed by a receive processor  238  to obtain decoded data and control information sent by UE  120 . Receive processor  238  may provide the decoded data to a data sink  239  and the decoded control information to controller/processor  240 . Base station  110  may include communication unit  244  and communicate to network controller  130  via communication unit  244 . Base station  110  may include a scheduler  246  to schedule UEs  120  for downlink and/or uplink communications. In some aspects, a modulator and a demodulator (e.g., MOD/DEMOD  232 ) of the base station  110  may be included in a modem of the base station  110 . In some aspects, the base station  110  includes a transceiver. The transceiver may include any combination of antenna(s)  234 , modulators and/or demodulators  232 , MIMO detector  236 , receive processor  238 , transmit processor  220 , and/or TX MIMO processor  230 . The transceiver may be used by a processor (e.g., controller/processor  240 ) and memory  242  to perform aspects of any of the methods described herein (for example, as described with reference to  FIGS.  6 A,  6 B, and  7   ). 
     Controller/processor  240  of base station  110 , controller/processor  280  of UE  120 , and/or any other component(s) of  FIG.  2    may perform one or more techniques associated with radio link control (RLC) layer feedback reporting for rateless codes, as described in more detail elsewhere herein. For example, controller/processor  240  of base station  110 , controller/processor  280  of UE  120 , and/or any other component(s) of  FIG.  2    may perform or direct operations of, for example, process  700  of  FIG.  7    and/or other processes as described herein. Memories  242  and  282  may store data and program codes for base station  110  and UE  120 , respectively. In some aspects, memory  242  and/or memory  282  may include a non-transitory computer-readable medium storing one or more instructions (e.g., code and/or program code) for wireless communication. For example, the one or more instructions, when executed (e.g., directly, or after compiling, converting, and/or interpreting) by one or more processors of the base station  110  and/or the UE  120 , may cause the one or more processors, the UE  120 , and/or the base station  110  to perform or direct operations of, for example, process  700  of  FIG.  7    and/or other processes as described herein. In some aspects, executing instructions may include running the instructions, converting the instructions, compiling the instructions, and/or interpreting the instructions, among other exmaples. 
     In some aspects, UE  120  may include means for determining that a quantity of a first plurality of RLC protocol data unit (PDU) packets, received from a transmitter, satisfies a first quantity threshold, means for performing a decoding attempt for the first plurality of RLC PDU packets based at least in part on determining that the quantity of the first plurality of RLC PDU packets satisfies the first quantity threshold, means for transmitting, to the transmitter, an RLC layer feedback report for the first plurality of RLC PDU packets after receiving a second plurality of RLC PDU packets from the transmitter, wherein the second plurality of RLC PDU packets are received after the first plurality of RLC PDU packets, and wherein the RLC layer feedback report is based at least in part on the decoding attempt, and/or the like. In some aspects, such means may include one or more components of UE  120  described in connection with  FIG.  2   , such as controller/processor  280 , transmit processor  264 , TX MIMO processor  266 , MOD  254 , antenna  252 , DEMOD  254 , MIMO detector  256 , receive processor  258 , and/or the like. 
     In some aspects, base station  110  may include means for determining that a quantity of a first plurality of RLC PDU packets, received from a transmitter, satisfies a first quantity threshold, means for performing a decoding attempt for the first plurality of RLC PDU packets based at least in part on determining that the quantity of the first plurality of RLC PDU packets satisfies the first quantity threshold, means for determining that a quantity of a second plurality of RLC PDU packets, received from the transmitter after receiving the first plurality of RLC PDU packets, satisfies a second quantity threshold, means for transmitting, to the transmitter, an RLC layer feedback report for the first plurality of RLC PDU packets based at least in part on determining that the quantity of the second plurality of RLC PDU packets satisfies the second quantity threshold, wherein the RLC layer feedback report is based at least in part on the decoding attempt, and/or the like. In some aspects, such means may include one or more components of base station  110  described in connection with  FIG.  2   , such as antenna  234 , DEMOD  232 , MIMO detector  236 , receive processor  238 , controller/processor  240 , transmit processor  220 , TX MIMO processor  230 , MOD  232 , antenna  234 , and/or the like. 
     While blocks in  FIG.  2    are illustrated as distinct components, the functions described above with respect to the blocks may be implemented in a single hardware, software, or combination component or in various combinations of components. For example, the functions described with respect to the transmit processor  264 , the receive processor  258 , and/or the TX MIMO processor  266  may be performed by or under the control of controller/processor  280 . 
     As indicated above,  FIG.  2    is provided as an example. Other examples may differ from what is described with regard to  FIG.  2   . 
       FIG.  3    illustrates an example logical architecture of a distributed RAN  300 , according to aspects of the present disclosure. A 5G access node (AN)  306  may include an access node controller (ANC)  302 . The ANC may be a central unit (CU) of the distributed RAN  300 . The backhaul interface to the next generation core network (NG-CN or NG-Core)  304  may terminate at the ANC. The backhaul interface to neighboring next generation access nodes (NG-ANs) may terminate at the ANC. The ANC may include one or more TRPs  308  (which may also be referred to as BSs, NR BSs, Node Bs, 5G NBs, APs, gNB, or some other term). As described above, “TRP” may be used interchangeably with “cell.” 
     The TRPs  308  may be a distributed unit (DU). The TRPs may be connected to one ANC (ANC  302 ) or more than one ANC (not illustrated). For example, for RAN sharing, radio as a service (RaaS), and service specific AND deployments, the TRP may be connected to more than one ANC. A TRP may include one or more antenna ports. The TRPs may be configured to individually (e.g., dynamic selection) or jointly (e.g., joint transmission) serve traffic to a UE. 
     The local architecture of RAN  300  may be used to illustrate fronthaul communication. The architecture may be defined to support fronthauling solutions across different deployment types. For example, the architecture may be based at least in part on transmit network capabilities (e.g., bandwidth, latency, and/or jitter). 
     The architecture may share features and/or components with LTE. According to aspects, the next generation AN (NG-AN)  310  may support dual connectivity with NR. The NG-AN may share a common fronthaul for LTE and NR. 
     The architecture may enable cooperation between and among TRPs  308 . For example, cooperation may be preset within a TRP and/or across TRPs via the ANC  302 . According to aspects, no inter-TRP interface may be needed/present. 
     According to aspects, a dynamic configuration of split logical functions may be present within the architecture of RAN  300 . The packet data convergence protocol (PDCP), RLC, or medium access control (MAC) protocol may be adaptably placed at the ANC or TRP. 
     According to various aspects, a BS may include a CU (e.g., ANC  302 ) and/or one or more DUs (e.g., one or more TRPs  308 ). In some aspects, a BS (e.g., 5G AN  306 ) may provide, broadcast, multicast, and/or unicast support to one or more UEs  120  via the example distributed RAN  300  illustrated in  FIG.  3   . For example, a BS may receive a multicast broadcast (MB) quality of service (QoS) flow from a 5G user plane function (UPF) device (e.g., a network controller  130 ) in NG-CN  304 . The BS may receive the MB QoS flow via an N 3  user plane interface and over a tunneling protocol (e.g., a general packet radio service (GPRS) Tunneling Protocol or another type of tunneling protocol). The BS may receive the MB QoS flow at a CU (e.g., ANC  302 ). A 5G access and mobility management function (AMF) device (e.g., a network controller  130 ) may provide control signaling to the CU over an N 2  interface to set up and/or modify the MB QoS flow. The BS may map the MB QoS flow to one or more multicast radio bearers (MRBs) and may provide the MB QoS flow to one or more DUs (e.g., one or more TRPs  308 ) via the one or more MRBs. The DUs may multicast or broadcast the MB QoS flow to one or more UEs  120 . 
     As indicated above,  FIG.  3    is provided as an example. Other examples may differ from what is described with regard to  FIG.  3   . 
       FIG.  4    illustrates an example physical architecture of a distributed RAN  400 , according to aspects of the present disclosure. A centralized core network unit (C-CU)  402  may host core network functions, which may be implemented by one or more network controllers  130 . The core network functions may include a 5G UPF, a 5G AMF, and/or other core network functions. The C-CU may be centrally deployed. C-CU functionality may be offloaded (e.g., to advanced wireless services (AWS)), in an effort to handle peak capacity. 
     A centralized RAN unit (C-RU)  404  may host one or more ANC functions. Optionally, the C-RU may host core network functions locally. The C-RU may have distributed deployment. The C-RU may be closer to the network edge. A DU  406  may host one or more TRPs. The DU may be located at edges of the network with radio frequency (RF) functionality. 
     In some aspects, a BS may provide broadcast, multicast, and/or unicast support to one or more UEs  120  via the example distributed RAN  400  illustrated in  FIG.  4   . For example, a BS may receive an MB QoS flow from a 5G UPF device (e.g., a network controller  130 ) of C-CU  402 . The BS may receive the MB QoS flow via an N 3  user plane interface and over a tunneling protocol (e.g., a GPRS Tunneling Protocol or another type of tunneling protocol). The BS may receive the MB QoS flow at C-RU  404 . A 5G AMF device (e.g., a network controller  130 ) of C-CU  402  may provide control signaling to C-RU  404  over an N 2  interface to set up and/or modify the MB QoS flow. The BS may map the MB QoS flow to one or more MRBs and may provide the MB QoS flow to one or more DUs  406  via the one or more MRBs. DUs  406  may multicast or broadcast the MB QoS flow to one or more UEs  120 . 
     As indicated above,  FIG.  4    is provided as an example. Other examples may differ from what is described with regard to  FIG.  4   . 
       FIG.  5    is a diagram illustrating an example  500  of network coding, in accordance with the present disclosure. The operations described in connection with  FIG.  5    may be performed by a transmitter (also referred to as an encoder), such as a UE  120  or a base station  110 . 
     As shown by reference number  505 , a transmitter may generate an RLC service data unit (SDU) from one or more PDCP protocol data units (PDUs). In some aspects, a single PDCP PDU may be included in an RLC SDU. In some aspects, multiple PDCP PDUs may be included in an RLC SDU (e.g., by concatenating multiple PDCP PDUs). In some aspects, the transmitter may determine whether to include a single PDCP PDU in a single RLC SDU or whether to concatenate multiple PDCP PDUs in a single RLC SDU based at least in part on a size of the PDCP PDU. For example, if the size of the PDCP PDU satisfies a threshold (e.g., is greater than or equal to the threshold), then the encoder may include only the PDCP PDU (e.g., a single PDCP PDU) in a single RLC SDU. If the size of the PDCP PDU does not satisfy a threshold (e.g., is less than or equal to the threshold), then the encoder may concatenate multiple PDCP PDUs (e.g., a set of PDCP PDUs with a total size that is less than or equal to the threshold) into a single RLC SDU. 
     As shown by reference number  510 , the transmitter may divide the RLC SDU into a plurality of data blocks. For example, the transmitter may divide the RLC SDU into K data blocks, shown as si through s K , based at least in part on the set of network coding parameters. In some aspects, the set of network coding parameters may specify the value of K for a particular set of sub-parameters, such as a payload size for the RLC SDU, a size of a sequence number field in an RLC PDU header for the RLC SDU, and/or the like. In some aspects, the encoder may determine the value of K for a set of sub-parameters. 
     In some aspects, the operations associated with reference number  505  and  510  may be performed at the PDCP layer of the transmitter. The PDCP layer may provide the data blocks to the RLC layer of the transmitter. As shown by reference number  515 , the transmitter may encode the K data blocks into N forward error correction (FEC) packets using network coding. For example, the transmitter may encode the K data blocks into the NFEC packets, shown as pi through p N , based at least in part on a rateless code, such as a network code, a fountain code, a Luby transform (LT) code, a Raptor code, and/or the like. In particular, the transmitter may encode the K data blocks into the N FEC packets such that the N FEC packets include additional information or bits for purposes of forward error correction. This permits FEC packets to be recovered by a receiver, for example, if the quantity of received FEC packets is larger than the quantity of K data blocks regardless of which FEC packets are received. 
     In some aspects, the number of RLC packets (e.g., the value of N) may be based at least in part on the set of network coding parameters. In some aspects, the set of network coding parameters may specify the value of N for a particular set of sub-parameters, a delay budget for the RLC SDU, available encoding and decoding computation resources of the transmitter, the value of K (e.g., the quantity of data blocks), a target error probability for one or more RLC PDU packets for the N FEC, channel conditions for transmission of the RLC PDU packets(s), the type of network code that is to be used to encode the K data blocks into the NFEC packets, and/or the like. In some aspects, the transmitter may determine the value of N for a set of sub-parameters. 
     As shown by reference number  520 , the transmitter may map the N FEC packets to a corresponding M RLC PDU packets. For example, the transmitter may map N FEC packets to M RLC PDU packets, shown as PDU 1  through PDU M , such that each RLC PDU includes a plurality of FEC packets (e.g., two FEC packets per RLC PDU packet, four FEC packets per RLC PDU packet, and/or the like). In some aspects, the operations associated with reference number  515  and  520  may be performed at the RLC layer of the transmitter. The RLC layer may receive an indication of the set of network coding parameters from the RRC layer and may perform the operations associated with reference number  515  and  520  based at least in part on the set of network coding parameters. 
     The RLC layer may provide the M RLC PDU packets to the MAC layer of the transmitter. As shown by reference number  525 , the transmitter may generate a MAC PDU for the M RLC PDU packets. In some aspects, the MAC PDU may include an RLC PDU header or a MAC PDU header, which may include information associated with each of the M RLC PDUs. For example, the RLC PDU header or MAC PDU header may include a sequence number field, which may indicate a sequence number associated with each of the M RLC PDUs. In some aspects, the operations associated with reference number  525  may be performed at the MAC layer of the transmitter. 
     The MAC layer of the transmitter may provide the MAC PDU to the physical (PHY) layer of the transmitter. As shown by reference number  530 , the encoder may transmit the M RLC PDU packets (e.g., in the MAC PDU) to a receiver (also referred to as a decoder), such as a UE  120  or a base station  110 . In some aspects, the PHY layer of the transmitter may transmit the M RLC PDU packets (e.g., in the MAC PDU) over a wireless physical channel, such as a physical downlink shared channel (PDSCH), a physical downlink control channel (PDCCH), a physical uplink shared channel (PUSCH), a physical uplink control channel (PDCCH), a physical sidelink control channel (PSCCH), a physical sidelink shared channel (PSSCH), and/or the like. 
     As indicated above,  FIG.  5    is provided as an example. Other examples may differ from what is described with respect to  FIG.  5   . 
     In some cases, a transmitter and a receiver may implement an automatic repeat request (ARQ) at an RLC layer to increase the reliability and robustness of RLC layer communication between the transmitter and the receiver. In some cases, an ARQ scheme for the RLC layer may include a poll request/status report technique, in which the transmitter transmits a poll request to the receiver and the receiver responds with a status report. The poll request may be transmitted for an RLC window of RLC PDU packets, and the status report may indicate an acknowledgement (ACK) or negative acknowledgement (NACK) for each RLC PDU packet in the RLC window. Each poll request may slide the window forward by a particular quantity of RLC PDU packets. Moreover, each ACK and NACK may indicate a sequence number for an associated RLC PDU packet. 
     However, the poll request/status report technique may be inefficient in that the transmitter is to stop transmissions of additional RLC PDU packets until a retransmission of a failed RLC PDU packet (e.g., an RLC PDU packet for which a NACK is received) is performed. Moreover, the poll request/status report technique may be inefficient in that the poll request/status report technique does not take advantage of the forward error correction capabilities of rateless codes such as network codes or fountain codes. 
     Some aspects described herein provide techniques and apparatuses for RLC layer feedback reporting for rateless codes. In some aspects, a receiver (e.g., a UE  120 , a base station  110 , and/or the like) may receive a plurality of RLC PDU packets that each include one or more FEC packets that are encoded using a rateless network code. The receiver is capable of determining when to transmit an RLC layer feedback report of the plurality of packets based at least in part on a quantity of the plurality of RLC PDU packets. In this way, the receiver is capable of transmitting RLC layer feedback for the plurality of RLC PDU packets without having to wait for a polling request from the transmitter, which reduces processing and memory resources of the transmitter, and radio network resources that would otherwise have been consumed on generating and transmitting the polling request. Moreover, the receiver can include various types of RLC layer feedback in the RLC layer feedback report to assist the transmitter in determining which FEC packets to retransmit, to assist the transmitter in determining whether to adjust network coding parameters for subsequent RLC PDU packets, to assist the transmitter in determining whether to transmit additional RLC PDU packets for more robust decoding and forward error correction, and/or the like. 
       FIGS.  6 A and  6 B  are diagrams illustrating one or more examples  600  associated with RLC feedback reporting for rateless codes, in accordance with the present disclosure. As shown in  FIGS.  6 A and  6 B , example(s)  600  may include communication between a transmitter and a receiver. The transmitter and the receiver may be included in a wireless network such as wireless network  100 . The transmitter and the receiver may respectively be a base station  110  and a UE  120 , or vice-versa, that communicate on a wireless access link (which may include an uplink and a downlink), may be a set of UEs  120  that communicate on a wireless sidelink, may be a set of base stations  110  that communicate on a backhaul, or may be another combination of wireless communication devices. 
     As shown in  FIG.  6 A , and by reference number  602 , the transmitter may transmit a first plurality of RLC PDU packets (e.g., RLC PDU packet 1 through RLC PDU packet L) to the receiver. In some aspects, the transmitter is capable of network coding the packets according to the techniques described above in connection with  FIG.  5    and/or other network coding techniques. Accordingly, each of the first plurality of RLC PDU packets, or a subset thereof, may be encoded to include one or more FEC packets. 
     As further shown in  FIG.  6 A , and by reference number  604 , the receiver may receive the first plurality of RLC PDU packets and may determine that a quantity of the first plurality of RLC PDU packets satisfies a first threshold. The first threshold may be a threshold quantity L of RLC PDU packets. In some aspects, the receiver may determine the threshold quantity L of RLC PDU packets based at least in part on an RLC configuration at an RLC layer of the receiver. In some aspects, the RLC configuration may be configured by an RRC layer of the receiver. In some aspects, the threshold quantity L of RLC PDU packets may be programmed at the receiver, may be hardcoded at the receiver, may be defined in a wireless communication standard, a wireless communication specification, and/or the like. In some aspects, the threshold quantity L of RLC PDU packets may be signaled to the receiver by the transmitter or another wireless communication device. 
     In some aspects, the receiver may perform forward error correction across the first plurality of RLC PDU packets. In these cases, the value of L may be configured based at least in part on an expected quantity of RLC PDU packets that permits the receiver to perform forward error correction across the first plurality of RLC PDU packets. An example value for L may be 1000 RLC PDU packets. However, other values for L may be used, and may be based at least in part on receiver implementation (e.g., the available decoding computation resources of the receiver), channel conditions of the wireless channel on which the transmitter and the receiver communicate, a target error probability for the first plurality of RLC PDU packets, the type of network code that is to encode the FEC packets of the first plurality of RLC PDU packets, and/or the like. 
     As further shown in  FIG.  6 A , and by reference number  606 , the receiver may perform a decoding attempt of the first plurality of RLC PDU packets. In some aspects, the receiver may perform the decoding attempt of the first plurality of RLC PDU packets based at least in part on determining that the quantity of the first plurality of RLC PDU packets satisfies the first threshold (e.g., the threshold quantity L of RLC PDU). In some aspects, the receiver may perform the decoding attempt by attempting to decode each of the first plurality of RLC PDU packets. 
     In some aspects, the receiver may attempt to decode the first plurality of RLC PDU packets by determining whether the receiver can recover the data blocks of the original RLC SDU that are included in the first plurality of RLC PDU. In some aspects, the receiver may determine if any of the FEC packets in the first plurality of RLC PDU packet are lost or undecodable. If one or more of the FEC packets are lost or undecodable in an RLC PDU packet, the receiver may attempt to recover the data blocks of the lost or undecodable FEC packets by performing forward error correction using other FEC packets in the RLC PDU packet and/or in other RLC PDU packets of the first plurality of RLC PDU packets. In these examples, the receiver may use the additional information or bits encoded in other FEC packets to recreate or infer the data blocks of the lost or undecodable FEC packets. 
     Alternatively to determining that an L quantity of RLC PDU packets has been successfully received, and performing the decoding attempt for the L quantity of RLC PDU packets based at least in part on determining that the L quantity of RLC PDU packets has been successfully received, the receiver may perform the decoding attempt after receiving an RLC PDU packet having a packet sequence number (SN) greater than L. In these aspects, the receiver determines that an RLC PDU packet having a packet SN greater than L (e.g., L+1 or another packet SN greater than L) was received (e.g., from the transmitter), and performs the decoding attempt for RLC PDU packets 1 through L that were successfully received based at least in part on determining that an RLC PDU packet having a packet SN greater than L was received. 
     As shown in  FIG.  6 B , and by reference number  608 , the transmitter may transmit a second plurality of RLC PDU packets (e.g., RLC PDU packet L+1 through RLC PDU packet L+Δ) to the receiver. In some aspects, each of the second plurality of RLC PDU packets, or a subset thereof, may be encoded to include one or more FEC packets using the network coding techniques described above in connection with  FIG.  5    and/or other network coding techniques. 
     As further shown in  FIG.  6 B , and by reference number  610 , the receiver may determine that a quantity of the second plurality of RLC PDU packets satisfies a second threshold. The second threshold may be a threshold quantity Δ of RLC PDU packets received after or subsequent to reception of the threshold quantity L of RLC PDU packets. In some aspects, the receiver may determine the threshold quantity Δ of RLC PDU packets based at least in part on an RLC configuration at an RLC layer of the receiver. In some aspects, the RLC configuration may be configured by an RRC layer of the receiver. In some aspects, the threshold quantity Δ of RLC PDU packets may be programmed at the receiver, may be hardcoded at the receiver, may be defined in a wireless communication standard, a wireless communication specification, and/or the like. In some aspects, the threshold quantity Δ of RLC PDU packets may be signaled to the receiver by the transmitter or another wireless communication device. 
     An example value for Δ may be 6 RLC PDU packets. As another example, the value for Δ may be 0 RLC PDU packets (e.g., the receiver is to transmit an RLC layer feedback report immediately after generating the RLC layer feedback report). However, other values for Δ may be used. In some aspects, the first quantity threshold (L) and the second quantity threshold (Δ) may be configured together (e.g., in the same RLC configuration). In some aspects, the first quantity threshold (L) and the second quantity threshold (Δ) are correlated. For example, the value for first quantity threshold (L) may be based at least in part on the SDU size of the SDU in which the first plurality of RLC PDU packets is included, and the value for the second quantity threshold (Δ) may be based at least in part on the value for the first quantity threshold (L). 
     As further shown in  FIG.  6 B , and by reference number  612 , the receiver may transmit an RLC layer feedback report to the transmitter. In some aspects, the receiver may transmit the RLC layer feedback report based at least in part on determining that the quantity of the second plurality of RLC PDU packets satisfies the second threshold (e.g., the threshold quantity Δ of RLC PDU packets). 
     The RLC layer feedback report may be for the first plurality of RLC PDU packets and may be based at least in part on the decoding attempt for the first plurality of RLC PDU packets. In some aspects, the RLC layer feedback report may include feedback information associated with the first plurality of RLC PDU packets. For example, the RLC layer feedback report may include information identifying an ACK or a NACK for the first plurality of RLC PDU packets as a whole (e.g., an ACK indicating that the data blocks of the first plurality of RLC PDU packets were decoded and/or recovered, a NACK indicating that one or more RLC PDU packets could not be decoded and/or were not recoverable, and/or the like). As another example, the RLC layer feedback report may include information identifying an ACK or a NACK for each of the first plurality of RLC PDU packets. 
     As another example, the RLC layer feedback report may include information identifying a quantity of failed RLC PDU packets (e.g., RLC PDU packets that are lost or undecodable), of the first plurality of RLC PDU packets, for the decoding attempt. As another example, the RLC layer feedback report may include information identifying a quantity of failed FEC packets (e.g., FEC packets that are lost or undecodable), included in an RLC PDU packet of the first plurality of RLC PDU packets, for the decoding attempt. As another example, the RLC layer feedback report may include information identifying an index associated with a failed FEC encoded packet, included in an RLC PDU packet of the first plurality of RLC PDU packets, for the decoding attempt. 
     Alternatively to determining that a Δ quantity of RLC PDU packets has been received after the L RLC PDU packets, and transmitting the RLC layer feedback report based at least in part on determining that the Δ quantity of RLC PDU packets has been received after the L RLC PDU packets, the receiver may transmit the RLC layer feedback report after receiving an RLC PDU packet having a packet SN greater than a particular packet SN (e.g., which is a higher packet SN than the packet SN associated with the RLC PDU packet based on which the receiver determined to perform the decoding attempt for the L RLC PDU packets). 
     In some aspects, the receiver tracks a counter of RLC PDU packets received by the receiver. The receiver may reset the counter based at least in part on determining that a counter threshold of RLC PDU packets (e.g., of C RLC PDU packets) has been received (e.g., quantity of packet SNs &gt; C). The threshold of RLC PLD packets (e.g., C) may be configured as an indicator for a maximum length of FEC encoded RLC PDU packets. 
     In this way, the receiver is capable of transmitting RLC layer feedback for the plurality of RLC PDU packets without having to wait for a polling request from the transmitter, which reduces processing and memory resources of the transmitter, and radio network resources that would otherwise have been consumed on generating and transmitting the polling request. Moreover, the receiver can include various types of RLC layer feedback in the RLC layer feedback report to assist the transmitter in determining which FEC packets to retransmit, to assist the transmitter in determining whether to adjust network coding parameters for subsequent RLC PDU packets, to assist the transmitter in determining whether to transmit additional RLC PDU packets for more robust decoding and forward error correction, and/or the like. 
     In some aspects, the techniques described in connection with  FIGS.  6 A and  6 B  may be extended to be implemented at the PDCP layer in a similar manner. 
     As indicated above,  FIGS.  6 A and  6 B  are provided as one or more examples. Other examples may differ from what is described with respect to  FIGS.  6 A and  6 B . 
       FIG.  7    is a diagram illustrating an example process  700  performed, for example, by a receiver, in accordance with the present disclosure. Example process  700  is an example where the receiver (e.g., a UE  120 , a base station  110 , and/or the like) performs operations associated with RLC layer feedback reporting for rateless codes. 
     As shown in  FIG.  7   , in some aspects, process  700  may include determining that a quantity of a first plurality of RLC PDU packets, received from a transmitter, satisfies a first quantity threshold (block  710 ). For example, the receiver (e.g., using transmit processor  200 , receive processor  238 , controller/processor  240 , memory  242 , receive processor  258 , transmit processor  264 , controller/processor  280 , memory  282 , and/or the like) may determine that a quantity of a first plurality of RLC PDU packets, received from a transmitter, satisfies a first quantity threshold, as described above. 
     As further shown in  FIG.  7   , in some aspects, process  700  may include performing a decoding attempt for the first plurality of RLC PDU packets based at least in part on determining that the quantity of the first plurality of RLC PDU packets satisfies the first quantity threshold (block  720 ). For example, the receiver (e.g., using transmit processor  200 , receive processor  238 , controller/processor  240 , memory  242 , receive processor  258 , transmit processor  264 , controller/processor  280 , memory  282 , and/or the like) may perform a decoding attempt for the first plurality of RLC PDU packets based at least in part on determining that the quantity of the first plurality of RLC PDU packets satisfies the first quantity threshold, as described above. 
     As further shown in  FIG.  7   , in some aspects, process  700  may include transmitting, to the transmitter, an RLC layer feedback report for the first plurality of RLC PDU packets after receiving a second plurality of RLC PDU packets from the transmitter, wherein the second plurality of RLC PDU packets are received after the first plurality of RLC PDU packets, and wherein the RLC layer feedback report is based at least in part on the decoding attempt (block  730 ). For example, the receiver (e.g., using transmit processor  200 , receive processor  238 , controller/processor  240 , memory  242 , receive processor  258 , transmit processor  264 , controller/processor  280 , memory  282 , and/or the like) may transmit, to the transmitter, an RLC layer feedback report for the first plurality of RLC PDU packets after receiving a second plurality of RLC PDU packets from the transmitter, as described above. In some aspects, the second plurality of RLC PDU packets are received after the first plurality of RLC PDU packets. In some aspects, the RLC layer feedback report is based at least in part on the decoding attempt. 
     Process  700  may include additional aspects, such as any single aspect or any combination of aspects described below and/or in connection with one or more other processes described elsewhere herein. 
     In a first aspect, each of the first plurality of RLC PDU packets includes a plurality of FEC encoded packets. In a second aspect, alone or in combination with the first aspect, the plurality of FEC encoded packets, included in each of the first plurality of RLC PDU packets, are FEC encoded using a rateless network code. In a third aspect, alone or in combination with the first or second aspects, process  700  includes determining that a quantity of the second plurality of RLC PDU packets satisfies a second quantity threshold, wherein transmitting the RLC layer feedback report includes transmitting, to the transmitter, an RLC layer feedback report for the first plurality of RLC PDU packets based at least in part on determining that the quantity of the second plurality of RLC PDU packets satisfies the second quantity threshold. 
     In a fourth aspect, alone or in combination with one or more of the first through third aspects, the first quantity threshold and the second quantity threshold are indicated in an RLC layer configuration, and the RLC layer configuration is configured at a radio resource control (RRC) layer for the receiver. In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the RLC layer feedback report includes information identifying an ACK or a NACK for an RLC PDU packet of the first plurality of RLC PDU packets. 
     In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, the RLC layer feedback report includes information identifying a quantity of failed RLC PDU packets, of the first plurality of RLC PDU packets, for the decoding attempt. In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, the RLC layer feedback report includes information identifying a quantity of failed FEC encoded packets, included in an RLC PDU packet of the first plurality of RLC PDU packets, for the decoding attempt. In a eighth aspect, alone or in combination with one or more of the first through seventh aspects, the RLC layer feedback report includes information identifying an index associated with a failed FEC encoded packet, included in an RLC PDU packet of the first plurality of RLC PDU packets, for the decoding attempt. 
     In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, the first quantity threshold and the second quantity threshold are correlated and configured together. In a tenth aspect, alone or in combination with one or more of the first through ninth aspects, the second quantity threshold is based at least in part on the second quantity threshold. In an eleventh aspect, alone or in combination with one or more of the first through tenth aspects, the first quantity threshold is based at least in part on a service data unit size for the first plurality of RLC PDU packets. In a twelfth aspect, alone or in combination with one or more of the first through eleventh aspects, the second quantity threshold is 0 RLC PDU packets. 
     Although  FIG.  7    shows example blocks of process  700 , in some aspects, process  700  may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in  FIG.  7   . Additionally, or alternatively, two or more of the blocks of process  700  may be performed in parallel. 
       FIG.  8    is a diagram illustrating an example process  800  performed, for example, by a receiver, in accordance with the present disclosure. Example process  800  is an example where the receiver (e.g., a UE  120  or a base station  110 ) performs operations associated with RLC layer feedback reporting for rateless codes. 
     As shown in  FIG.  8   , in some aspects, process  800  may include determining that an RLC PDU packet having a particular packet SN was received from a transmitter (block  810 ). For example, the receiver (e.g., using transmit processor  200 , receive processor  238 , controller/processor  240 , memory  242 , receive processor  258 , transmit processor  264 , controller/processor  280 , memory  282 , and/or the like) may determine that an RLC PDU packet having a particular packet SN was received from a transmitter, as described above. 
     As further shown in  FIG.  8   , in some aspects, process  800  may include performing, based at least in part on determining that the RLC PDU packet having the particular packet SN was received, a decoding attempt for a plurality of RLC PDU packets that were received from the transmitter, wherein the plurality of RLC PDU packets have packet SNs lower than the particular packet SN of the RLC PDU packet (block  820 ). For example, the receiver (e.g., using transmit processor  200 , receive processor  238 , controller/processor  240 , memory  242 , receive processor  258 , transmit processor  264 , controller/processor  280 , memory  282 , and/or the like) may perform, based at least in part on determining that the RLC PDU packet having the particular packet SN was received, a decoding attempt for a plurality of RLC PDU packets that were received from the transmitter, wherein the plurality of RLC PDU packets have packet SNs lower than the particular packet SN of the RLC PDU packet, as described above. In some aspects, the plurality of RLC PDU packets have packet SNs lower than the particular packet SN of the RLC PDU packet. 
     Process  800  may include additional aspects, such as any single aspect or any combination of aspects described below and/or in connection with one or more other processes described elsewhere herein. 
     In a first aspect, process  800  includes determining that another RLC PDU packet having another particular packet SN was received from the transmitter, wherein the other RLC PDU packet was received after receiving the RLC PDU packet, and transmitting, to the transmitter, an RLC layer feedback report for the plurality of RLC PDU packets based at least in part on determining that the other RLC PDU packet having the other particular packet SN was received, wherein the RLC layer feedback report is based at least in part on the decoding attempt. 
     In a second aspect, alone or in combination with the first aspect, process  800  includes determining that a quantity of another plurality of RLC PDU packets, received from the transmitter after receiving the plurality of RLC PDU packets, satisfies a quantity threshold, and transmitting, to the transmitter, an RLC layer feedback report for the plurality of RLC PDU packets based at least in part on determining that the quantity of the other plurality of RLC PDU packets satisfies the quantity threshold, wherein the RLC layer feedback report is based at least in part on the decoding attempt. In a third aspect, alone or in combination with one or more of the first or second aspects, process  800  includes transmitting an RLC layer feedback report to the transmitter prior to receiving a request from the transmitter for the RLC layer feedback report. 
     Although  FIG.  8    shows example blocks of process  800 , in some aspects, process  800  may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in  FIG.  8   . Additionally, or alternatively, two or more of the blocks of process  800  may be performed in parallel. 
     The following provides an overview of some Aspects of the present disclosure: 
     Aspect 1: A method of wireless communication performed by a receiver, comprising: determining that a quantity of a first plurality of radio link layer (RLC) protocol data unit (PDU) packets, received from a transmitter, satisfies a first quantity threshold; performing a decoding attempt for the first plurality of RLC PDU packets based at least in part on determining that the quantity of the first plurality of RLC PDU packets satisfies the first quantity threshold; and transmitting, to the transmitter, an RLC layer feedback report for the first plurality of RLC PDU packets after receiving a second plurality of RLC PDU packets from the transmitter, wherein the second plurality of RLC PDU packets are received after the first plurality of RLC PDU packets, and wherein the RLC layer feedback report is based at least in part on the decoding attempt.   Aspect 2: The method of Aspect 1, wherein each of the first plurality of RLC PDU packets includes a plurality of forward error correction (FEC) encoded packets.   Aspect 3: The method of Aspect 2, wherein the plurality of FEC encoded packets, included in each of the first plurality of RLC PDU packets, are FEC encoded using a rateless network code. Aspect 4: The method of Aspect 1 or 2, further comprising: determining that a quantity of the second plurality of RLC PDU packets satisfies a second quantity threshold; and wherein transmitting the RLC layer feedback report comprises: transmitting, to the transmitter, an RLC layer feedback report for the first plurality of RLC PDU packets based at least in part on determining that the quantity of the second plurality of RLC PDU packets satisfies the second quantity threshold.   Aspect 5: The method of Aspect 4, wherein the first quantity threshold and the second quantity threshold are indicated in an RLC layer configuration; and wherein the RLC layer configuration is configured at a radio resource control (RRC) layer for the receiver. Aspect 6: The method of Aspect 5, wherein the first quantity threshold and the second quantity threshold are correlated and configured together. Aspect 7: The method of any of Aspects 4-6, wherein the second quantity threshold is based at least in part on the second quantity threshold.   Aspect 8: The method of any of Aspects 4-7, wherein the first quantity threshold is based at least in part on a service data unit size for the first plurality of RLC PDU packets. Aspect 9: The method of any of Aspects 4-8, wherein the second quantity threshold is 0 RLC PDU packets. Aspect 10: The method of any of Aspects 1-9, wherein the RLC layer feedback report includes information identifying an acknowledgement (ACK) or a negative acknowledgement (NACK) for an RLC PDU packet of the first plurality of RLC PDU packets. Aspect 11: The method of any of Aspects 1-10, wherein the RLC layer feedback report includes information identifying a quantity of failed RLC PDU packets, of the first plurality of RLC PDU packets, for the decoding attempt.   Aspect 12: The method of any of Aspects 1-11, wherein the RLC layer feedback report includes information identifying a quantity of failed forward error correction (FEC) encoded packets, included in an RLC PDU packet of the first plurality of RLC PDU packets, for the decoding attempt. Aspect 13: The method of any of Aspects 1-12, wherein the RLC layer feedback report includes information identifying an index associated with a failed forward error correction (FEC) encoded packet, included in an RLC PDU packet of the first plurality of RLC PDU packets, for the decoding attempt.   Aspect 14: A method of wireless communication performed by a receiver, comprising: determining that a radio link layer (RLC) protocol data unit (PDU) packet having a particular packet sequence number (SN) was received from a transmitter; and performing, based at least in part on determining that the RLC PDU packet having the particular packet SN was received, a decoding attempt for a plurality of RLC PDU packets that were received from the transmitter, wherein the plurality of RLC PDU packets have packet SNs lower than the particular packet SN of the RLC PDU packet;   Aspect 15: The method of Aspect 14, further comprising: determining that another RLC PDU packet having another particular packet SN was received from the transmitter, wherein the other RLC PDU packet was received after receiving the RLC PDU packet; and transmitting, to the transmitter, an RLC layer feedback report for the plurality of RLC PDU packets based at least in part on determining that the other RLC PDU packet having the other particular packet SN was received, wherein the RLC layer feedback report is based at least in part on the decoding attempt. Aspect 16: The method of Aspect 14, further comprising: determining that a quantity of another plurality of RLC PDU packets, received from the transmitter after receiving the plurality of RLC PDU packets, satisfies a quantity threshold; and transmitting, to the transmitter, an RLC layer feedback report for the plurality of RLC PDU packets based at least in part on determining that the quantity of the other plurality of RLC PDU packets satisfies the quantity threshold, wherein the RLC layer feedback report is based at least in part on the decoding attempt. Aspect 17: The method of any of Aspects 14-16, further comprising: transmitting an RLC layer feedback report to the transmitter prior to receiving a request from the transmitter for the RLC layer feedback report.   Aspect 18: An apparatus for wireless communication at a device, comprising a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform the method of one or more of Aspects 1-13. Aspect 19: A device for wireless communication, comprising a memory and one or more processors coupled to the memory, the one or more processors configured to perform the method of one or more of Aspects 1-13.   Aspect 20: An apparatus for wireless communication, comprising at least one means for performing the method of one or more of Aspects 1-13. Aspect 21: A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by a processor to perform the method of one or more of Aspects 1-13. Aspect 22: A non-transitory computer-readable medium storing a set of instructions for wireless communication, the set of instructions comprising one or more instructions that, when executed by one or more processors of a device, cause the device to perform the method of one or more of Aspects 1-13.   Aspect 22: An apparatus for wireless communication at a device, comprising a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform the method of one or more of Aspects 14-17. Aspect 23: A device for wireless communication, comprising a memory and one or more processors coupled to the memory, the one or more processors configured to perform the method of one or more of Aspects 14-17.   Aspect 24: An apparatus for wireless communication, comprising at least one means for performing the method of one or more of Aspects 14-17. Aspect 25: A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by a processor to perform the method of one or more of Aspects 14-17. Aspect 26: A non-transitory computer-readable medium storing a set of instructions for wireless communication, the set of instructions comprising one or more instructions that, when executed by one or more processors of a device, cause the device to perform the method of one or more of Aspects 14-17.   

     The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit the aspects to the precise form disclosed. Modifications and variations may be made in light of the above disclosure or may be acquired from practice of the aspects. 
     As used herein, the term “component” is intended to be broadly construed as hardware and/or a combination of hardware and software. “Software” shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, and/or functions, among other examples, whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise. As used herein, a processor is implemented in hardware, firmware, and/or a combination of hardware and software. It will be apparent that systems and/or methods described herein may be implemented in different forms of hardware and/or a combination of hardware and software. The actual specialized control hardware or software code used to implement these systems and/or methods is not limiting of the aspects. Thus, the operation and behavior of the systems and/or methods were described herein without reference to specific software code—it being understood that software and hardware can be designed to implement the systems and/or methods based, at least in part, on the description herein. 
     As used herein, satisfying a threshold may, depending on the context, refer to a value being greater than the threshold, greater than or equal to the threshold, less than the threshold, less than or equal to the threshold, equal to the threshold, not equal to the threshold, or the like. 
     Even though particular combinations of features are recited in the claims and/or disclosed in the specification, these combinations are not intended to limit the disclosure of various aspects. In fact, many of these features may be combined in ways not specifically recited in the claims and/or disclosed in the specification. Although each dependent claim listed below may directly depend on only one claim, the disclosure of various aspects includes each dependent claim in combination with every other claim in the claim set. As used herein, a phrase referring to “at least one of” a list of items refers to any combination of those items, including single members. As an example, “at least one of: a, b, or c” is intended to cover a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combination with multiples of the same element (e.g., a-a, a-a-a, a-a-b, a-a-c, a-b-b, a-c-c, b-b, b-b-b, b-b-c, c-c, and c-c-c or any other ordering of a, b, and c). 
     No element, act, or instruction used herein should be construed as critical or essential unless explicitly described as such. Also, as used herein, the articles “a” and “an” are intended to include one or more items and may be used interchangeably with “one or more.” Further, as used herein, the article “the” is intended to include one or more items referenced in connection with the article “the” and may be used interchangeably with “the one or more.” Furthermore, as used herein, the terms “set” and “group” are intended to include one or more items (e.g., related items, unrelated items, or a combination of related and unrelated items), and may be used interchangeably with “one or more.” Where only one item is intended, the phrase “only one” or similar language is used. Also, as used herein, the terms “has,” “have,” “having,” or the like are intended to be open-ended terms. Further, the phrase “based on” is intended to mean “based, at least in part, on” unless explicitly stated otherwise. Also, as used herein, the term “or” is intended to be inclusive when used in a series and may be used interchangeably with “and/or,” unless explicitly stated otherwise (e.g., if used in combination with “either” or “only one of”).