WO2021223236A1

WO2021223236A1 - Unequal erasure protection for prioritized data transmission

Info

Publication number: WO2021223236A1
Application number: PCT/CN2020/089252
Authority: WO
Inventors: Kangqi LIU; Changlong Xu; Liangming WU; Jian Li; Hao Xu
Original assignee: Qualcomm Incorporated
Priority date: 2020-05-08
Filing date: 2020-05-08
Publication date: 2021-11-11

Abstract

Methods, systems, and devices for wireless communications are described. A transmitting device may use a fountain code scheme (e.g., a Luby transform (LT) code scheme or a rapid tornado (Raptor) code scheme) to encode a set of source symbols transmitted to a receiving device based on one or more priorities associated with the set of source symbols. Similarly, a receiving device may decode source symbols based on the associated priorities. In some examples, the transmitting device may use a precoding process that maps source symbols to a set of intermediate symbols, where the set of intermediate symbols includes a quantity of copies of each source symbol based on the priority of each source symbol. Additionally or alternatively, the set of source symbols may have a non-uniform distribution, where source symbols with a higher priority may have a higher probability of being selected and combined into encoding symbols.

Description

UNEQUAL ERASURE PROTECTION FOR PRIORITIZED DATA TRANSMISSION

FIELD OF TECHNOLOGY

The following relates generally to wireless communications and more specifically to unequal erasure protection for prioritized data transmission.

BACKGROUND

Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power) . Examples of such multiple-access systems include fourth generation (4G) systems such as Long Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, or LTE-A Pro systems, and fifth generation (5G) systems which may be referred to as New Radio (NR) systems. These systems may employ technologies such as code division multiple access (CDMA) , time division multiple access (TDMA) , frequency division multiple access (FDMA) , orthogonal frequency division multiple access (OFDMA) , or discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM) . A wireless multiple-access communications system may include one or more base stations or one or more network access nodes, each simultaneously supporting communication for multiple communication devices, which may be otherwise known as user equipment (UE) .

Packets may be exchanged between network nodes (e.g., base stations, UEs, etc. ) to transmit information in wireless communications systems. Packets may be encoded to improve the reliability of the transmitted information. In some cases, encoded packets may provide redundancy, which may be used to correct errors that result from the transmission environment (e.g., path loss, obstacles, etc. ) . Some examples of encoding algorithms with error correcting codes include fountain codes, such as Luby transform (LT) codes or rapid tornado (Raptor) codes.

SUMMARY

The described techniques relate to improved methods, systems, devices, and apparatuses that support unequal erasure protection for prioritized data transmission. Generally, the described techniques provide for enabling a transmitting device to encode a set of source symbols according to a fountain code scheme based on one or more priorities associated with the set of source symbols. Similarly, the described techniques may enable a receiving device to decode source symbols based on the associated priorities.

In some examples, the transmitting device may use a precoding process that maps source symbols to a set of intermediate symbols, where the set of intermediate symbols includes a quantity of copies of each source symbol based on the priority of each source symbol. For example, the set of intermediate symbols may include more copies of a source symbol with a higher priority than copies of a source symbol with a lower priority. Additionally or alternatively, the set of source symbols may have a non-uniform distribution, where source symbols with a higher priority may have a higher probability of being selected and combined into encoding symbols.

A method of wireless communications at a first wireless device is described. The method may include determining one or more priorities associated with a set of source symbols, selecting a priority set of the one or more priorities, where one or more source symbols of the set of source symbols are associated with the priority set, receiving, from a second wireless device, one or more packets encoded according to a fountain code, and decoding the one or more packets to recover the one or more source symbols associated with the priority set.

An apparatus for wireless communications at a first wireless device is described. The apparatus may include a processor, memory coupled with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to determine one or more priorities associated with a set of source symbols, select a priority set of the one or more priorities, where one or more source symbols of the set of source symbols are associated with the priority set, receive, from a second wireless device, one or more packets encoded according to a fountain code, and decode the one or more packets to recover the one or more source symbols associated with the priority set.

Another apparatus for wireless communications at a first wireless device is described. The apparatus may include means for determining one or more priorities associated with a set of source symbols, selecting a priority set of the one or more priorities, where one or more source symbols of the set of source symbols are associated with the priority set, receiving, from a second wireless device, one or more packets encoded according to a fountain code, and decoding the one or more packets to recover the one or more source symbols associated with the priority set.

A non-transitory computer-readable medium storing code for wireless communications at a first wireless device is described. The code may include instructions executable by a processor to determine one or more priorities associated with a set of source symbols, select a priority set of the one or more priorities, where one or more source symbols of the set of source symbols are associated with the priority set, receive, from a second wireless device, one or more packets encoded according to a fountain code, and decode the one or more packets to recover the one or more source symbols associated with the priority set.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for determining that the one or more source symbols associated with the priority set of the one or more packets may be recovered, and transmitting a feedback message to the second wireless device based on recovering the one or more source symbols associated with the priority set of the one or more packets.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for receiving, from the second wireless device, one or more additional packets encoded according to the fountain code, where the one or more additional packets may be received based on transmission of the feedback message, and decoding the one or more additional packets to recover one or more additional source symbols associated with the priority set.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for determining a transmission duration associated with the one or more packets, where the one or more packets may be received from the second wireless device during the transmission duration, determining a remaining portion of the transmission duration after recovering the one or more source symbols associated with the priority set, selecting an additional priority set of the one or more priorities, where one or more additional source symbols of the set of source symbols may be associated with the additional priority set, receiving, from the second wireless device, one or more additional packets in the remaining portion, and decoding the one or more packets and one or more additional packets to recover the one or more additional source symbols associated with the additional priority set.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for receiving, from the second wireless device, an indication of the transmission duration, where the transmission duration may be determined based on receiving the indication.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the decoding may include operations, features, means, or instructions for determining a set of encoding symbols in the received one or more packets, identifying an encoding symbol of the set of encoding symbols that includes a source symbol of the set of source symbols, determining a priority associated with the source symbol in the identified encoding symbol, and applying a logic operation to one or more encoding symbols of the set of encoding symbols based on the source symbol in the identified encoding symbol and the determined priority associated with the source symbol.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the priority associated with the source symbol may be in the selected priority set.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the one or more source symbols associated with the priority set may be recovered based on applying the logic operation.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the logic operation includes an exclusive OR logic operation.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the fountain code includes a Luby transform (LT) code, a rapid tornado (Raptor) code, or both.

A method of wireless communications at a second wireless device is described. The method may include determining one or more priorities associated with a set of source symbols, encoding a set of packets according to a fountain code, where each packet of the set of packets is constructed from one or more source symbols of the set of source symbols according to a distribution based on the one or more priorities, and transmitting the set of packets to a first wireless device.

An apparatus for wireless communications at a second wireless device is described. The apparatus may include a processor, memory coupled with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to determine one or more priorities associated with a set of source symbols, encode a set of packets according to a fountain code, where each packet of the set of packets is constructed from one or more source symbols of the set of source symbols according to a distribution based on the one or more priorities, and transmit the set of packets to a first wireless device.

Another apparatus for wireless communications at a second wireless device is described. The apparatus may include means for determining one or more priorities associated with a set of source symbols, encoding a set of packets according to a fountain code, where each packet of the set of packets is constructed from one or more source symbols of the set of source symbols according to a distribution based on the one or more priorities, and transmitting the set of packets to a first wireless device.

A non-transitory computer-readable medium storing code for wireless communications at a second wireless device is described. The code may include instructions executable by a processor to determine one or more priorities associated with a set of source symbols, encode a set of packets according to a fountain code, where each packet of the set of packets is constructed from one or more source symbols of the set of source symbols according to a distribution based on the one or more priorities, and transmit the set of packets to a first wireless device.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for receiving a feedback message from the first wireless device based on transmitting the set of packets, where the feedback message indicates that one or more source symbols of the set of source symbols were recovered at the first wireless device.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for encoding an additional set of packets according to the fountain code, where each packet of the additional set of packets may be constructed from one or more additional source symbols according to the distribution based on the one or more priorities, and transmitting the additional set of packets to the first wireless device.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for determining a transmission duration associated with the set of packets, where the set of packets may be transmitted to the first wireless device in the transmission duration.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for receiving a feedback message from the first wireless device based on transmitting the set of packets, determining a remaining portion of the transmission duration after receiving the feedback message, and transmitting, to the first wireless device, one or more packets of the set of packets in the remaining portion.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for transmitting, to the first wireless device, an indication of the transmission duration.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the encoding may include operations, features, means, or instructions for mapping one or more source symbols of the set of source symbols to each intermediate symbol of a set of intermediate symbols, selecting a degree from a degree distribution associated with the fountain code, selecting one or more intermediate symbols of the set of intermediate symbols based on the selected degree, and combining the selected one or more intermediate symbols into an encoding symbol, where each packet of the set of packets includes one or more encoding symbols.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the set of intermediate symbols include a set of low-density parity-check (LDPC) symbols, and each source symbol of the set of source symbols may be mapped to a quantity of LDPC symbols based on a respective priority associated with the source symbol.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the encoding may include operations, features, means, or instructions for determining a respective probability associated with each source symbol of the set of source symbols based on a respective priority associated with the source symbol, where selecting the one or more intermediate symbols of the set of intermediate symbols may be further based on the respective probabilities associated with the mapped one or more source symbols.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the selected one or more intermediate symbols may be combined based on an exclusive OR logic operation.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the fountain code includes an LT code, a Raptor code, or both.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGs. 1 and 2 illustrate examples of wireless communications systems that support unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure.

FIG. 3 illustrates an example of a encoding scheme that supports unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure.

FIG. 4 illustrates an example of a process flow that supports unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure.

FIGs. 5 and 6 show block diagrams of devices that support unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure.

FIG. 7 shows a block diagram of a communications manager that supports unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure.

FIG. 8 shows a diagram of a system including a device that supports unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure.

FIGs. 9 and 10 show block diagrams of devices that support unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure.

FIG. 11 shows a block diagram of a communications manager that supports unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure.

FIG. 12 shows a diagram of a system including a device that supports unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure.

FIGs. 13 through 17 show flowcharts illustrating methods that support unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure.

DETAILED DESCRIPTION

Some wireless communication systems, such as fifth generation (5G) systems which may be referred to as New Radio (NR) systems, may include network nodes that exchange packets via communications links. A network node, such as a user equipment (UE) , a base station, an integrated access and backhaul (IAB) relay node, or another wireless device, may encode packets before transmission to improve reliability of a destination node successfully receiving the transmitted information. In some cases, encoded packets may provide redundancy, which may be used to correct errors that result from the transmission environment (e.g., path loss, obstacles, etc. ) .

Some examples of encoding algorithms with error correcting codes include fountain codes, such as Luby transform (LT) codes or rapid tornado (Raptor) codes. A fountain code may be an example of a rateless code, where a set of source symbols (e.g., K symbols) may be encoded as any quantity of encoding symbols (e.g., a quantity of symbols greater than K symbols) . Encoding the source symbols may include combining one or more source symbols into each encoding symbol. The encoding may include using a degree distribution, where the degree distribution represents a probability mass function of a set of degrees d _i (e.g., d ₁, d ₂, d ₃, etc. ) . The probability of randomly selecting a degree d _i (i.e., a degree with index i) from the degree distribution may be represented by ρ (i) . In the encoding process, the degree d _i may represent the quantity of source symbols which may be combined into a given encoding symbol.

The encoding symbols may be transmitted as a set of encoded packets from a transmitting device (e.g., a base station) to a receiving device (e.g., a UE) . In some examples, one or more encoded packets may be lost based on the transmission environment. The receiving device may receive a subset of the encoded packets. Based on the encoding and combining, the receiving device may decode the set of source symbols from the subset of encoded packets despite the packet loss.

In some examples, one or more priorities may be associated with a set of source symbols. For example, a first portion of the set may have a higher priority than a second portion. It may be beneficial to configure encoding and decoding of source symbols based on associated priorities, for example to reduce latency in communications between a transmitting device and the receiving device.

According to the techniques described herein, a transmitting device may encode a set of source symbols according to a fountain code scheme based on one or more priorities associated with the set of source symbols. Similarly, the techniques described herein may enable a receiving device to decode source symbols based on the associated priorities.

The transmitting device may transmit a data transmission as a set of packets to the receiving device, where the packets may include the encoding symbols. The receiving device may select a priority set from the one or more priorities associated with the set of source symbols. The receiving device may decode one or more packets to recover the source symbols associated with the selected priority set. In some examples, the receiving device may transmit feedback (e.g., a hybrid automatic repeat request (HARQ) acknowledgment (ACK) ) to the transmitting device after recovering the source symbols associated with the selected priority set. Additionally or alternatively, the receiving device may identify a duration for decoding the data transmission, for example as determined by the transmitting device. Once the receiving device recovers the source symbols associated with the selected priority set, the receiving device may transmit feedback (e.g., an ACK) to the transmitting device. If there is time remaining in the duration, the receiving device may decode additional source symbols not associated with the selected priority set.

Aspects of the disclosure are initially described in the context of wireless communications systems. An example encoding scheme and an example process flow are then described. Aspects of the disclosure are further illustrated by and described with reference to apparatus diagrams, system diagrams, and flowcharts that relate to unequal erasure protection for prioritized data transmission.

FIG. 1 illustrates an example of a wireless communications system 100 that supports unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure. The wireless communications system 100 may include one or more base stations 105, one or more UEs 115, and a core network 130. In some examples, the wireless communications system 100 may be a Long Term Evolution (LTE) network, an LTE-Advanced (LTE-A) network, an LTE-A Pro network, or a New Radio (NR) network. In some examples, the wireless communications system 100 may support enhanced broadband communications, ultra-reliable (e.g., mission critical) communications, low latency communications, communications with low-cost and low-complexity devices, or any combination thereof.

The base stations 105 may be dispersed throughout a geographic area to form the wireless communications system 100 and may be devices in different forms or having different capabilities. The base stations 105 and the UEs 115 may wirelessly communicate via one or more communication links 125. Each base station 105 may provide a coverage area 110 over which the UEs 115 and the base station 105 may establish one or more communication links 125. The coverage area 110 may be an example of a geographic area over which a base station 105 and a UE 115 may support the communication of signals according to one or more radio access technologies.

The UEs 115 may be dispersed throughout a coverage area 110 of the wireless communications system 100, and each UE 115 may be stationary, or mobile, or both at different times. The UEs 115 may be devices in different forms or having different capabilities. Some example UEs 115 are illustrated in FIG. 1. The UEs 115 described herein may be able to communicate with various types of devices, such as other UEs 115, the base stations 105, or network equipment (e.g., core network nodes, relay devices, integrated access and backhaul (IAB) nodes, or other network equipment) , as shown in FIG. 1.

The base stations 105 may communicate with the core network 130, or with one another, or both. For example, the base stations 105 may interface with the core network 130 through one or more backhaul links 120 (e.g., via an S1, N2, N3, or other interface) . The base stations 105 may communicate with one another over the backhaul links 120 (e.g., via an X2, Xn, or other interface) either directly (e.g., directly between base stations 105) , or indirectly (e.g., via core network 130) , or both. In some examples, the backhaul links 120 may be or include one or more wireless links.

One or more of the base stations 105 described herein may include or may be referred to by a person having ordinary skill in the art as a base transceiver station, a radio base station, an access point, a radio transceiver, a NodeB, an eNodeB (eNB) , a next-generation NodeB or a giga-NodeB (either of which may be referred to as a gNB) , a Home NodeB, a Home eNodeB, or other suitable terminology.

A UE 115 may include or may be referred to as a mobile device, a wireless device, a remote device, a handheld device, or a subscriber device, or some other suitable terminology, where the “device” may also be referred to as a unit, a station, a terminal, or a client, among other examples. A UE 115 may also include or may be referred to as a personal electronic device such as a cellular phone, a personal digital assistant (PDA) , a tablet computer, a laptop computer, or a personal computer. In some examples, a UE 115 may include or be referred to as a wireless local loop (WLL) station, an Internet of Things (IoT) device, an Internet of Everything (IoE) device, or a machine type communications (MTC) device, among other examples, which may be implemented in various objects such as appliances, or vehicles, meters, among other examples.

The UEs 115 described herein may be able to communicate with various types of devices, such as other UEs 115 that may sometimes act as relays as well as the base stations 105 and the network equipment including macro eNBs or gNBs, small cell eNBs or gNBs, or relay base stations, among other examples, as shown in FIG. 1.

The UEs 115 and the base stations 105 may wirelessly communicate with one another via one or more communication links 125 over one or more carriers. The term “carrier” may refer to a set of radio frequency spectrum resources having a defined physical layer structure for supporting the communication links 125. For example, a carrier used for a communication link 125 may include a portion of a radio frequency spectrum band (e.g., a bandwidth part (BWP) ) that is operated according to one or more physical layer channels for a given radio access technology (e.g., LTE, LTE-A, LTE-A Pro, NR) . Each physical layer channel may carry acquisition signaling (e.g., synchronization signals, system information) , control signaling that coordinates operation for the carrier, user data, or other signaling. The wireless communications system 100 may support communication with a UE 115 using carrier aggregation or multi-carrier operation. A UE 115 may be configured with multiple downlink component carriers and one or more uplink component carriers according to a carrier aggregation configuration. Carrier aggregation may be used with both frequency division duplexing (FDD) and time division duplexing (TDD) component carriers.

Signal waveforms transmitted over a carrier may be made up of multiple subcarriers (e.g., using multi-carrier modulation (MCM) techniques such as orthogonal frequency division multiplexing (OFDM) or discrete Fourier transform spread OFDM (DFT-S-OFDM) ) . In a system employing MCM techniques, a resource element may consist of one symbol period (e.g., a duration of one modulation symbol) and one subcarrier, where the symbol period and subcarrier spacing are inversely related. The number of bits carried by each resource element may depend on the modulation scheme (e.g., the order of the modulation scheme, the coding rate of the modulation scheme, or both) . Thus, the more resource elements that a UE 115 receives and the higher the order of the modulation scheme, the higher the data rate may be for the UE 115. A wireless communications resource may refer to a combination of a radio frequency spectrum resource, a time resource, and a spatial resource (e.g., spatial layers or beams) , and the use of multiple spatial layers may further increase the data rate or data integrity for communications with a UE 115.

The time intervals for the base stations 105 or the UEs 115 may be expressed in multiples of a basic time unit which may, for example, refer to a sampling period of T _s=1/ (Δf _max·N _f) seconds, where Δf _max may represent the maximum supported subcarrier spacing, and N _f may represent the maximum supported discrete Fourier transform (DFT) size. Time intervals of a communications resource may be organized according to radio frames each having a specified duration (e.g., 10 milliseconds (ms) ) . Each radio frame may be identified by a system frame number (SFN) (e.g., ranging from 0 to 1023) .

Each frame may include multiple consecutively numbered subframes or slots, and each subframe or slot may have the same duration. In some examples, a frame may be divided (e.g., in the time domain) into subframes, and each subframe may be further divided into a number of slots. Alternatively, each frame may include a variable number of slots, and the number of slots may depend on subcarrier spacing. Each slot may include a number of symbol periods (e.g., depending on the length of the cyclic prefix prepended to each symbol period) . In some wireless communications systems 100, a slot may further be divided into multiple mini-slots containing one or more symbols. Excluding the cyclic prefix, each symbol period may contain one or more (e.g., N _f) sampling periods. The duration of a symbol period may depend on the subcarrier spacing or frequency band of operation.

A subframe, a slot, a mini-slot, or a symbol may be the smallest scheduling unit (e.g., in the time domain) of the wireless communications system 100 and may be referred to as a transmission time interval (TTI) . In some examples, the TTI duration (e.g., the number of symbol periods in a TTI) may be variable. Additionally or alternatively, the smallest scheduling unit of the wireless communications system 100 may be dynamically selected (e.g., in bursts of shortened TTIs (sTTIs) ) .

Physical channels may be multiplexed on a carrier according to various techniques. A physical control channel and a physical data channel may be multiplexed on a downlink carrier, for example, using one or more of time division multiplexing (TDM) techniques, frequency division multiplexing (FDM) techniques, or hybrid TDM-FDM techniques. A control region (e.g., a control resource set (CORESET) ) for a physical control channel may be defined by a number of symbol periods and may extend across the system bandwidth or a subset of the system bandwidth of the carrier. One or more control regions (e.g., CORESETs) may be configured for a set of the UEs 115. For example, one or more of the UEs 115 may monitor or search control regions for control information according to one or more search space sets, and each search space set may include one or multiple control channel candidates in one or more aggregation levels arranged in a cascaded manner. An aggregation level for a control channel candidate may refer to a number of control channel resources (e.g., control channel elements (CCEs) ) associated with encoded information for a control information format having a given payload size. Search space sets may include common search space sets configured for sending control information to multiple UEs 115 and UE-specific search space sets for sending control information to a specific UE 115.

In some examples, a base station 105 may be movable and therefore provide communication coverage for a moving geographic coverage area 110. In some examples, different geographic coverage areas 110 associated with different technologies may overlap, but the different geographic coverage areas 110 may be supported by the same base station 105. In other examples, the overlapping geographic coverage areas 110 associated with different technologies may be supported by different base stations 105. The wireless communications system 100 may include, for example, a heterogeneous network in which different types of the base stations 105 provide coverage for various geographic coverage areas 110 using the same or different radio access technologies.

The wireless communications system 100 may be configured to support ultra-reliable communications or low-latency communications, or various combinations thereof. For example, the wireless communications system 100 may be configured to support ultra-reliable low-latency communications (URLLC) or mission critical communications. The UEs 115 may be designed to support ultra-reliable, low-latency, or critical functions (e.g., mission critical functions) . Ultra-reliable communications may include private communication or group communication and may be supported by one or more mission critical services such as mission critical push-to-talk (MCPTT) , mission critical video (MCVideo) , or mission critical data (MCData) . Support for mission critical functions may include prioritization of services, and mission critical services may be used for public safety or general commercial applications. The terms ultra-reliable, low-latency, mission critical, and ultra-reliable low-latency may be used interchangeably herein.

In some examples, a UE 115 may also be able to communicate directly with other UEs 115 over a device-to-device (D2D) communication link 135 (e.g., using a peer-to-peer (P2P) or D2D protocol) . One or more UEs 115 utilizing D2D communications may be within the geographic coverage area 110 of a base station 105. Other UEs 115 in such a group may be outside the geographic coverage area 110 of a base station 105 or be otherwise unable to receive transmissions from a base station 105. In some examples, groups of the UEs 115 communicating via D2D communications may utilize a one-to-many (1: M) system in which each UE 115 transmits to every other UE 115 in the group. In some examples, a base station 105 facilitates the scheduling of resources for D2D communications. In other cases, D2D communications are carried out between the UEs 115 without the involvement of a base station 105.

The core network 130 may provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. The core network 130 may be an evolved packet core (EPC) or 5G core (5GC) , which may include at least one control plane entity that manages access and mobility (e.g., a mobility management entity (MME) , an access and mobility management function (AMF) ) and at least one user plane entity that routes packets or interconnects to external networks (e.g., a serving gateway (S-GW) , a Packet Data Network (PDN) gateway (P-GW) , or a user plane function (UPF) ) . The control plane entity may manage non-access stratum (NAS) functions such as mobility, authentication, and bearer management for the UEs 115 served by the base stations 105 associated with the core network 130. User IP packets may be transferred through the user plane entity, which may provide IP address allocation as well as other functions. The user plane entity may be connected to the network operators IP services 150. The operators IP services 150 may include access to the Internet, Intranet (s) , an IP Multimedia Subsystem (IMS) , or a Packet-Switched Streaming Service.

Some of the network devices, such as a base station 105, may include subcomponents such as an access network entity 140, which may be an example of an access node controller (ANC) . Each access network entity 140 may communicate with the UEs 115 through one or more other access network transmission entities 145, which may be referred to as radio heads, smart radio heads, or transmission/reception points (TRPs) . Each access network transmission entity 145 may include one or more antenna panels. In some configurations, various functions of each access network entity 140 or base station 105 may be distributed across various network devices (e.g., radio heads and ANCs) or consolidated into a single network device (e.g., a base station 105) .

The wireless communications system 100 may operate using one or more frequency bands, typically in the range of 300 megahertz (MHz) to 300 gigahertz (GHz) . Generally, the region from 300 MHz to 3 GHz is known as the ultra-high frequency (UHF) region or decimeter band because the wavelengths range from approximately one decimeter to one meter in length. The UHF waves may be blocked or redirected by buildings and environmental features, but the waves may penetrate structures sufficiently for a macro cell to provide service to the UEs 115 located indoors. The transmission of UHF waves may be associated with smaller antennas and shorter ranges (e.g., less than 100 kilometers) compared to transmission using the smaller frequencies and longer waves of the high frequency (HF) or very high frequency (VHF) portion of the spectrum below 300 MHz.

The wireless communications system 100 may utilize both licensed and unlicensed radio frequency spectrum bands. For example, the wireless communications system 100 may employ License Assisted Access (LAA) , LTE-Unlicensed (LTE-U) radio access technology, or NR technology in an unlicensed band such as the 5 GHz industrial, scientific, and medical (ISM) band. When operating in unlicensed radio frequency spectrum bands, devices such as the base stations 105 and the UEs 115 may employ carrier sensing for collision detection and avoidance. In some examples, operations in unlicensed bands may be based on a carrier aggregation configuration in conjunction with component carriers operating in a licensed band (e.g., LAA) . Operations in unlicensed spectrum may include downlink transmissions, uplink transmissions, P2P transmissions, or D2D transmissions, among other examples.

A base station 105 or a UE 115 may be equipped with multiple antennas, which may be used to employ techniques such as transmit diversity, receive diversity, multiple-input multiple-output (MIMO) communications, or beamforming. The antennas of a base station 105 or a UE 115 may be located within one or more antenna arrays or antenna panels, which may support MIMO operations or transmit or receive beamforming. For example, one or more base station antennas or antenna arrays may be co-located at an antenna assembly, such as an antenna tower. In some examples, antennas or antenna arrays associated with a base station 105 may be located in diverse geographic locations. A base station 105 may have an antenna array with a number of rows and columns of antenna ports that the base station 105 may use to support beamforming of communications with a UE 115. Likewise, a UE 115 may have one or more antenna arrays that may support various MIMO or beamforming operations. Additionally or alternatively, an antenna panel may support radio frequency beamforming for a signal transmitted via an antenna port.

The base stations 105 or the UEs 115 may use MIMO communications to exploit multipath signal propagation and increase the spectral efficiency by transmitting or receiving multiple signals via different spatial layers. Such techniques may be referred to as spatial multiplexing. The multiple signals may, for example, be transmitted by the transmitting device via different antennas or different combinations of antennas. Likewise, the multiple signals may be received by the receiving device via different antennas or different combinations of antennas. Each of the multiple signals may be referred to as a separate spatial stream and may carry bits associated with the same data stream (e.g., the same codeword) or different data streams (e.g., different codewords) . Different spatial layers may be associated with different antenna ports used for channel measurement and reporting. MIMO techniques include single-user MIMO (SU-MIMO) , where multiple spatial layers are transmitted to the same receiving device, and multiple-user MIMO (MU-MIMO) , where multiple spatial layers are transmitted to multiple devices.

Beamforming, which may also be referred to as spatial filtering, directional transmission, or directional reception, is a signal processing technique that may be used at a transmitting device or a receiving device (e.g., a base station 105, a UE 115) to shape or steer an antenna beam (e.g., a transmit beam, a receive beam) along a spatial path between the transmitting device and the receiving device. Beamforming may be achieved by combining the signals communicated via antenna elements of an antenna array such that some signals propagating at particular orientations with respect to an antenna array experience constructive interference while others experience destructive interference. The adjustment of signals communicated via the antenna elements may include a transmitting device or a receiving device applying amplitude offsets, phase offsets, or both to signals carried via the antenna elements associated with the device. The adjustments associated with each of the antenna elements may be defined by a beamforming weight set associated with a particular orientation (e.g., with respect to the antenna array of the transmitting device or receiving device, or with respect to some other orientation) .

The wireless communications system 100 may be a packet-based network that operates according to a layered protocol stack. In the user plane, communications at the bearer or Packet Data Convergence Protocol (PDCP) layer may be IP-based. A Radio Link Control (RLC) layer may perform packet segmentation and reassembly to communicate over logical channels. A Medium Access Control (MAC) layer may perform priority handling and multiplexing of logical channels into transport channels. The MAC layer may also use error detection techniques, error correction techniques, or both to support retransmissions at the MAC layer to improve link efficiency. In the control plane, the Radio Resource Control (RRC) protocol layer may provide establishment, configuration, and maintenance of an RRC connection between a UE 115 and a base station 105 or a core network 130 supporting radio bearers for user plane data. At the physical layer, transport channels may be mapped to physical channels.

The UEs 115 and the base stations 105 may support retransmissions of data to increase the likelihood that data is received successfully. HARQ feedback is one technique for increasing the likelihood that data is received correctly over a communication link 125. HARQ may include a combination of error detection (e.g., using a cyclic redundancy check (CRC) ) , forward error correction (FEC) , and retransmission (e.g., automatic repeat request (ARQ) ) . HARQ may improve throughput at the MAC layer in poor radio conditions (e.g., low signal-to-noise conditions) . In some examples, a device may support same-slot HARQ feedback, where the device may provide HARQ feedback in a specific slot for data received in a previous symbol in the slot. In other cases, the device may provide HARQ feedback in a subsequent slot, or according to some other time interval.

In some examples, a transmitting device (e.g., a base station 105 or a UE 115) may use a fountain code scheme (e.g., an LT or Raptor code scheme) to encode data transmitted to a receiving device (e.g., a UE 115 or a base station 105) . In some examples, the fountain code scheme may include a precoding process that maps source symbols to a set of intermediate symbols, where the set of intermediate symbols includes a quantity of copies of each source symbol based on the priority of each source symbol. For example, the set of intermediate symbols may include more copies of a source symbol with a higher priority than copies of a source symbol with a lower priority. Additionally or alternatively, the set of source symbols may have a non-uniform distribution, where source symbols with a higher priority may have a higher probability of being selected and combined into encoding symbols.

The transmitting device may transmit a data transmission as a set of packets to the receiving device, where the packets may include the encoding symbols. The receiving device may select a priority set from the one or more priorities associated with the set of source symbols. The receiving device may decode one or more packets to recover the source symbols associated with the selected priority set. In some examples, the receiving device may transmit feedback (e.g., a HARQ ACK message) to the transmitting device after recovering the source symbols associated with the selected priority set. Additionally or alternatively, the receiving device may identify a duration for decoding the data transmission, for example as determined by the transmitting device. Once the receiving device recovers the source symbols associated with the selected priority set, the receiving device may transmit feedback (e.g., an ACK) to the transmitting device. If there is time remaining in the duration, the receiving device may decode additional source symbols not associated with the selected priority set.

FIG. 2 illustrates an example of a wireless communications system 200 that supports unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure. In some examples, the wireless communications system 200 may implement aspects of wireless communications system 100. For example, the wireless communications system 200 may include a first wireless device 205 and a second wireless device 210, which may each be an example of a base station or a UE described with reference to FIG. 1. The wireless communications system 200 may include features for improved data encoding, transmission, and decoding, among other benefits.

The second wireless device 210 may transmit one or more data transmissions 220 to the first wireless device 205 via a channel 225. Each data transmission 220 may be transmitted as a set of encoded packets. Each encoded packet may include one or more encoding symbols encoded according to a fountain code (e.g., an LT code, a Raptor code, etc. ) . In some examples, one or more encoded packets may be lost based on the transmission environment. The first wireless device 205 may receive a subset of the encoded packets. Based on the encoding and combining, the receiving device may decode the set of source symbols from the subset of encoded packets despite the packet loss.

In some examples, one or more priorities may be associated with a set of source symbols. For example, a data transmission 220-a may include a video, and a set of source symbols may correspond to a set of video slices. A first portion of the set of video slices may correspond to a first resolution of the video (e.g., 360p) , and a second portion may correspond to a second resolution (e.g., 480p, 720p, 1080p, etc. ) higher than the first resolution. A first priority of the first portion may be greater than a second priority of the second portion. In some examples, the data transmission 220-a may be delay-sensitive, where it may be beneficial configure encoding and decoding of the set of source symbols based on the associated priorities. For example, the first wireless device 205 may prioritize decoding the video with the first resolution rather than waiting for the first wireless device 205 to decode the video with the second resolution to reduce latency in communications between the first wireless device 205 and the second wireless device 210.

In some examples, the second wireless device 210 may use a precoding process that maps the set of source symbols to a set of intermediate symbols, where the set of intermediate symbols includes a quantity of copies of each source symbol based on the priority of each source symbol. For example, the set of intermediate symbols may include more copies of a source symbol with a higher priority than copies of a source symbol with a lower priority. Additionally or alternatively, the set of source symbols may have a non-uniform distribution, where source symbols with a higher priority may have a higher probability of being selected and combined into encoding symbols.

The first wireless device 205 may receive one or more packets of the data transmission 220-a. The first wireless device 205 may select a priority set from the one or more priorities associated with the set of source symbols. The first wireless device 205 may decode the packets to recover the source symbols associated with the selected priority set. In some examples, the first wireless device 205 may transmit feedback 230 (e.g., a HARQ ACK) to the second wireless device 210 after recovering the source symbols associated with the selected priority set. Additionally or alternatively, the first wireless device 205 may identify a duration for decoding the data transmission 220-a, for example as determined by the second wireless device 210. Once the first wireless device 205 recovers the source symbols associated with the selected priority set, the first wireless device 205 may transmit the feedback 230 to the second wireless device 210. If there is time remaining in the duration, the first wireless device 205 may decode additional source symbols not associated with the selected priority set. For example, the first wireless device 205 may decode source symbols corresponding to the video with the first resolution. If there is time remaining in the duration, the first wireless device 205 may decode additional source symbols corresponding to the video with the second (higher) resolution.

In some examples, the second wireless device 210 may transmit a data transmission 220-b to the first wireless device 205. For example, the data transmission 220-b may be transmitted based on the feedback 230. The first wireless device 205 may decode packets of the data transmission 220 to recover source symbols associated with the selected priority set. The operations performed by the first wireless device 205 and the second wireless device 210 may support improvement to data encoding and transmission operations and, in some examples, may promote improvements to data decoding processes, among other benefits.

FIG. 3 illustrates an example of a encoding scheme 300 that supports unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure. In some examples, the encoding scheme 300 may implement aspects of

wireless communications systems

100 and 200. For example, the encoding scheme 300 may be associated with communications between a first wireless device (e.g., a receiving device) and a second wireless device (e.g., a transmitting device) , which may be examples of corresponding devices described with reference to FIGs. 1 and 2. The encoding scheme 300 may illustrate features for improved efficiency and reliability of communications, among other benefits.

The encoding scheme 300 may use Raptor coding to encode packets for transmission from the second wireless device to the first wireless device. The second wireless device may encode a set of source symbols 305 (e.g., a quantity K of source symbols 305) into a set of encoding symbols 325. The quantity of encoding symbols 325 may be greater than the quantity of source symbols 305 to improve a probability of successfully decoding the source symbols 305 at the first wireless device. In some examples, the encoding scheme 300 may be rateless, where the quantity of encoding symbols 325 may have no upper limit.

The encoding scheme 300 may include a precoding process 310. In the precoding process 310, the second wireless device may map one or more source symbols 305 to each of a set of intermediate symbols 315. The second wireless device may generate a quantity of redundant intermediate symbols 315 (e.g., a quantity of intermediate symbols 315 in addition to a quantity K of intermediate symbols 315 directly mapped to the K source symbols 305) . In some examples, the redundant intermediate symbols 315 may include a quantity S of low-density parity-check (LDPC) symbols, where one or more copies (e.g., three copies) of each source symbol 305 may appear in each LDPC symbol. Additionally or alternatively, the redundant intermediate symbols 315 may include a quantity H of half symbols, where each half symbol may include ceil (H/2) source symbols 305, and where ceil (x) may represent a ceiling function mapping x to a least integer greater than or equal to x.

The encoding scheme 300 may include an LT coding process 320 following the precoding process 310. In the LT coding process 320, the second wireless device may map the intermediate symbols 315 to the set of encoding symbols 325. The LT coding process 320 may employ a degree distribution Ω, where the degree distribution Ω represents a probability mass function of a set of degrees d _i (e.g., d ₁, d ₂, d ₃, etc. ) . The probability of randomly selecting a degree d _i (i.e., a degree with index i) from the degree distribution may be represented by ρ (i) . In the LT coding process 320, the degree d _i of an ith encoding symbol 325 may represent the quantity of intermediate symbols 315 which the second wireless device may combine into the ith encoding symbol 325. For example, if the selected degree for a first encoding symbol 325 is d ₁=2, two intermediate symbols 315 may be randomly selected and combined into the first encoding symbol 325. Similarly, if the selected degree for a second encoding symbol 325 is d ₂=1, a single intermediate symbol 315 may be combined into the second encoding symbol 325. In some examples, the intermediate symbols 315 may be combined into encoding symbols 325 using a logic operation such as a logic exclusive OR (XOR) operation. In some examples, each encoding symbol 325 may include information identifying the source symbols 305 used to construct the encoding symbol 325. For example, the encoding symbol may include indices (e.g., s ₁, s ₂, s ₃, s _K, etc. ) associated with the source symbols 305 used to construct the encoding symbol 325.

The encoding symbols 325 may be transmitted as a set of encoded packets from the second wireless device to the first wireless device. In some examples, the encoding scheme 300 may be represented by a generator matrix G. The source symbols 305 contained in encoding symbols 325 of a given encoded packet may be represented by p _j, which may be defined by:

In some examples, one or more encoded packets may be lost based on the transmission environment. The first wireless device may receive a subset of encoded packets (e.g., a quantity N of encoded packets) via the multi-hop network. The source symbols 305 contained in encoding symbols 325 of a given encoded packet received by the first wireless device may be represented by r _k, which may be defined by:

Based on the encoding scheme 300, the first wireless device may recover all source symbols 305 in the set of source symbols 305 when the matrix G′ of the received packets is invertible. Additionally or alternatively, the first wireless device may recover all source symbols 305 in the set of source symbols 305 when the matrix G′ of the received packets has a rank K, where K is the quantity of source symbols 305 in the set of source symbols 305. To increase a probability of the first wireless device successfully the set of source symbols 305, the encoding scheme 300 may be designed such that the representative generator matrix G′ is invertible for a minimum quantity N of received encoded packets.

The first wireless device may decode the received encoding symbols 325 to obtain the source symbols 305. The first wireless device may begin a decoding process by identifying an encoding symbol 325 with an index t _j that is connected to a single source symbol 305 with an index s _i. The first wireless device may determine the encoding symbol 325 with index t _j is equivalent to the source symbol 305 with index s _i. The first wireless device may then apply an XOR operation to each other encoding symbol 325 connected to the source symbol 305 with index s _i, and remove all edges connected to the source symbol 305 with index s _i. The first wireless device may repeat this process to recover source symbols 305 from the received encoding symbols 325.

In some examples, one or more priorities may be associated with the set of source symbols 305. For example, a first portion of the set may have a higher priority than a second portion of the set. It may be beneficial to configure encoding and decoding of the source symbols 305 based on associated priorities, for example to reduce latency in communications between the first wireless device and the second wireless device.

In some examples of the precoding process 310, the second wireless device may map the source symbols 305 to the intermediate symbols 315 based on the priorities associated with the source symbols 305, where the set of intermediate symbols 315 includes a quantity of copies of each source symbol 305 based on the priority of each source symbol 305. For example, the LDPC symbols in the set of intermediate symbols 315 may include more copies of a source symbol 305 with a higher priority than copies of a source symbol 305 with a lower priority. Additionally or alternatively, the set of source symbols 305 may have a non-uniform distribution, where intermediate symbols 315 corresponding to source symbols 305 with a higher priority may have a higher probability of being selected and combined into encoding symbols 325 in the LT coding process 320.

The first wireless device may select a priority set from the one or more priorities associated with the set of source symbols 305. The first wireless device may decode one or more packets to recover the source symbols 305 associated with the selected priority set. In some examples, the first wireless device may transmit feedback (e.g., a HARQ ACK) to the second wireless device after recovering the source symbols 305 associated with the selected priority set. Additionally or alternatively, the first wireless device may identify a duration for decoding the packets, for example as determined by the second wireless device. Once the first wireless device recovers the source symbols 305 associated with the selected priority set, the first wireless device may transmit feedback (e.g., an ACK) to the second wireless device. If there is time remaining in the duration, the first wireless device may decode additional source symbols 305 not associated with the selected priority set.

FIG. 4 illustrates an example of a process flow 400 that supports unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure. In some examples, the process flow 400 may implement aspects of

wireless communications systems

100 and 200. For example, the process flow 400 may include example operations associated with one or more of a first wireless device 405 and a second wireless device 410, which may be examples of the corresponding devices described with reference to FIGs. 1 and 2. In the following description of the process flow 400, the operations between the first wireless device 405 and the second wireless device 410 may be performed in a different order than the example order shown, or the operations performed by the first wireless device 405 and the second wireless device 410 may be performed in different orders or at different times. Some operations may also be omitted from the process flow 400, and other operations may be added to the process flow 400. The operations performed by the first wireless device 405 and the second wireless device 410 may support improvement to data encoding and transmission operations and, in some examples, may promote improvements to data decoding processes, among other benefits.

At 420, the first wireless device 405 and the second wireless device 410 may determine one or more priorities associated with a set of source symbols of a data transmission. For example, a first portion of the set of source symbols may have a first priority and a second portion may have a second priority, where the first priority is greater than the second priority. At 425, the first wireless device 405 may select a priority set of the priorities associated with the set of source symbols.

In some examples, at 430 the second wireless device 410 may determine a transmission duration for the first wireless device 405 to decode the source symbols of the data transmission. In some examples, at 435 the second wireless device 410 may indicate the transmission duration to the first wireless device 405.

At 440, the second wireless device 410 may encode a set of packets according to a fountain code (e.g., an LT code, a Raptor code, etc. ) . For example, the second wireless device may encode the set of packets according to the encoding scheme 300 described with reference to FIG. 3. The set of packets may include a set of encoding symbols constructed from combinations of the set of source symbols.

In some examples, the second wireless device 410 may use a precoding process that maps the source symbols to a set of intermediate symbols, where the set of intermediate symbols includes a quantity of copies of each source symbol based on the priority of each source symbol. For example, the set of intermediate symbols may include more copies of a source symbol with a higher priority than copies of a source symbol with a lower priority. Additionally or alternatively, the set of source symbols may have a non-uniform distribution, where source symbols with a higher priority may have a higher probability of being selected and combined into encoding symbols.

At 445, the second wireless device 410 may transmit the set of encoded packets to the first wireless device 405. The first wireless device 405 may receive one or more of the set of encoded packets. At 450, the first wireless device may decode the packets to recover the source symbols associated with the selected priority set, for example as described with reference to FIG. 3.

In some examples, at 455 the first wireless device 405 may transmit feedback (e.g., a HARQ ACK message) to the second wireless device 410. The feedback may indicate that the first wireless device 405 succeeded in recovering the source symbols associated with the selected priority set. In some examples, if there is time remaining in the transmission duration, the first wireless device 405 may decode additional source symbols not associated with the selected priority set.

In some examples, at 460 the second wireless device 410 may encode additional packets according to the fountain code. The additional packets may correspond to an additional data transmission. The second wireless device 410 may encode the additional packets based on receiving the feedback from the first wireless device 405. In some examples, at 465 the second wireless device 410 may transmit the additional encoded packets to the first wireless device 405. The first wireless device 405 may decode one or more of the additional encoded packets to recover source symbols associated with the selected priority set.

The operations performed by the first wireless device 405 and the second wireless device may support improvement to data encoding and transmission operations and, in some examples, may promote improvements to data decoding processes, among other benefits.

FIG. 5 shows a block diagram 500 of a device 505 that supports unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure. The device 505 may be an example of aspects of a first wireless device (e.g., a UE 115 or a base station 105) as described herein. The device 505 may include a receiver 510, a communications manager 515, and a transmitter 520. The device 505 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses) .

The receiver 510 may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to unequal erasure protection for prioritized data transmission, etc. ) . Information may be passed on to other components of the device 505. The receiver 510 may be an example of aspects of the transceiver 820 described with reference to FIG. 8. The receiver 510 may utilize a single antenna or a set of antennas.

The communications manager 515 may determine one or more priorities associated with a set of source symbols, select a priority set of the one or more priorities, where one or more source symbols of the set of source symbols are associated with the priority set, receive, from a second wireless device, one or more packets encoded according to a fountain code, and decode the one or more packets to recover the one or more source symbols associated with the priority set.

The communications manager 515 as described herein may be implemented to realize one or more potential advantages. One implementation may allow the device 505 to save power and increase battery life by communicating with the second wireless device (e.g., a base station 105 or a UE 115 as shown in FIG. 1) more efficiently. For example, the device 505 may reduce latency in communications and improve reliability by decoding packets based on the selected priority set. The communications manager 515 may be an example of aspects of the communications manager 810 described herein.

The communications manager 515, or its sub-components, may be implemented in hardware, code (e.g., software or firmware) executed by a processor, or any combination thereof. If implemented in code executed by a processor, the functions of the communications manager 515, or its sub-components may be executed by a general-purpose processor, a digital signal processor (DSP) , an application-specific integrated circuit (ASIC) , a field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described in the present disclosure.

The communications manager 515, or its sub-components, may be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations by one or more physical components. In some examples, the communications manager 515, or its sub-components, may be a separate and distinct component in accordance with various aspects of the present disclosure. In some examples, the communications manager 515, or its sub-components, may be combined with one or more other hardware components, including but not limited to an input/output (I/O) component, a transceiver, a network server, another computing device, one or more other components described in the present disclosure, or a combination thereof in accordance with various aspects of the present disclosure.

The transmitter 520 may transmit signals generated by other components of the device 505. In some examples, the transmitter 520 may be collocated with a receiver 510 in a transceiver module. For example, the transmitter 520 may be an example of aspects of the transceiver 820 described with reference to FIG. 8. The transmitter 520 may utilize a single antenna or a set of antennas.

FIG. 6 shows a block diagram 600 of a device 605 that supports unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure. The device 605 may be an example of aspects of a device 505, or a first wireless device (e.g., a UE 115 or a base station 105) as described herein. The device 605 may include a receiver 610, a communications manager 615, and a transmitter 640. The device 605 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses) .

The receiver 610 may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to unequal erasure protection for prioritized data transmission, etc. ) . Information may be passed on to other components of the device 605. The receiver 610 may be an example of aspects of the transceiver 820 described with reference to FIG. 8. The receiver 610 may utilize a single antenna or a set of antennas.

The communications manager 615 may be an example of aspects of the communications manager 515 as described herein. The communications manager 615 may include a source symbol priority component 620, a priority set selection manager 625, a packet receiving manager 630, and a decoder 635. The communications manager 615 may be an example of aspects of the communications manager 810 described herein.

The source symbol priority component 620 may determine one or more priorities associated with a set of source symbols.

The priority set selection manager 625 may select a priority set of the one or more priorities, where one or more source symbols of the set of source symbols are associated with the priority set.

The packet receiving manager 630 may receive, from a second wireless device, one or more packets encoded according to a fountain code.

The decoder 635 may decode the one or more packets to recover the one or more source symbols associated with the priority set.

The transmitter 640 may transmit signals generated by other components of the device 605. In some examples, the transmitter 640 may be collocated with a receiver 610 in a transceiver module. For example, the transmitter 640 may be an example of aspects of the transceiver 820 described with reference to FIG. 8. The transmitter 640 may utilize a single antenna or a set of antennas.

FIG. 7 shows a block diagram 700 of a communications manager 705 that supports unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure. The communications manager 705 may be an example of aspects of a communications manager 515, a communications manager 615, or a communications manager 810 described herein. The communications manager 705 may include a source symbol priority component 710, a priority set selection manager 715, a packet receiving manager 720, a decoder 725, a feedback manager 730, and a transmission duration component 735. Each of these modules may communicate, directly or indirectly, with one another (e.g., via one or more buses) .

The source symbol priority component 710 may determine one or more priorities associated with a set of source symbols.

The priority set selection manager 715 may select a priority set of the one or more priorities, where one or more source symbols of the set of source symbols are associated with the priority set. In some examples, the priority set selection manager 715 may select an additional priority set of the one or more priorities, where one or more additional source symbols of the set of source symbols are associated with the additional priority set.

The packet receiving manager 720 may receive, from a second wireless device, one or more packets encoded according to a fountain code. In some examples, the packet receiving manager 720 may receive, from the second wireless device, one or more additional packets encoded according to the fountain code, where the one or more additional packets are received based on transmission of the feedback message. In some examples, the packet receiving manager 720 may receive, from the second wireless device, one or more additional packets in the remaining portion. In some cases, the fountain code includes an LT code, a Raptor code, or both.

The decoder 725 may decode the one or more packets to recover the one or more source symbols associated with the priority set. In some examples, the decoder 725 may determine that the one or more source symbols associated with the priority set of the one or more packets are recovered. In some examples, the decoder 725 may decode the one or more additional packets to recover one or more additional source symbols associated with the priority set. In some examples, the decoder 725 may decode the one or more packets and one or more additional packets to recover the one or more additional source symbols associated with the additional priority set.

In some examples, the decoder 725 may determine a set of encoding symbols in the received one or more packets. In some examples, the decoder 725 may identify an encoding symbol of the set of encoding symbols that includes a source symbol of the set of source symbols. In some examples, the decoder 725 may determine a priority associated with the source symbol in the identified encoding symbol. In some examples, the decoder 725 may apply a logic operation to one or more encoding symbols of the set of encoding symbols based on the source symbol in the identified encoding symbol and the determined priority associated with the source symbol. In some cases, the priority associated with the source symbol is in the selected priority set. In some cases, the one or more source symbols associated with the priority set are recovered based on applying the logic operation. In some cases, the logic operation includes an exclusive OR logic operation.

The feedback manager 730 may transmit a feedback message to the second wireless device based on recovering the one or more source symbols associated with the priority set of the one or more packets.

The transmission duration component 735 may determine a transmission duration associated with the one or more packets, wherein the one or more packets are received from the second wireless device during the transmission duration. In some examples, the transmission duration component 735 may determine a remaining portion of the transmission duration after recovering the one or more source symbols associated with the priority set. In some examples, the transmission duration component 735 may receive, from the second wireless device, an indication of the transmission duration, where the transmission duration is determined based on receiving the indication.

FIG. 8 shows a diagram of a system 800 including a device 805 that supports unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure. The device 805 may be an example of or include the components of device 505, device 605, or a first wireless device (e.g., a UE 115 or a base station 105) as described herein. The device 805 may include components for bi-directional voice and data communications including components for transmitting and receiving communications, including a communications manager 810, an I/O controller 815, a transceiver 820, an antenna 825, memory 830, and a processor 840. These components may be in electronic communication via one or more buses (e.g., bus 845) .

The communications manager 810 may determine one or more priorities associated with a set of source symbols, select a priority set of the one or more priorities, where one or more source symbols of the set of source symbols are associated with the priority set, receive, from a second wireless device, one or more packets encoded according to a fountain code, and decode the one or more packets to recover the one or more source symbols associated with the priority set.

The I/O controller 815 may manage input and output signals for the device 805. The I/O controller 815 may also manage peripherals not integrated into the device 805. In some cases, the I/O controller 815 may represent a physical connection or port to an external peripheral. In some cases, the I/O controller 815 may utilize an operating system such as

or another known operating system. In other cases, the I/O controller 815 may represent or interact with a modem, a keyboard, a mouse, a touchscreen, or a similar device. In some cases, the I/O controller 815 may be implemented as part of a processor. In some cases, a user may interact with the device 805 via the I/O controller 815 or via hardware components controlled by the I/O controller 815.

The transceiver 820 may communicate bi-directionally, via one or more antennas, wired, or wireless links as described above. For example, the transceiver 820 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. The transceiver 820 may also include a modem to modulate the packets and provide the modulated packets to the antennas for transmission, and to demodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 825. However, in some cases the device may have more than one antenna 825, which may be capable of concurrently transmitting or receiving multiple wireless transmissions.

The memory 830 may include random-access memory (RAM) and read-only memory (ROM) . The memory 830 may store computer-readable, computer-executable code 835 including instructions that, when executed, cause the processor to perform various functions described herein. In some cases, the memory 830 may contain, among other things, a basic input/output system (BIOS) which may control basic hardware or software operation such as the interaction with peripheral components or devices.

The processor 840 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a central processing unit (CPU) , a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof) . In some cases, the processor 840 may be configured to operate a memory array using a memory controller. In other cases, a memory controller may be integrated into the processor 840. The processor 840 may be configured to execute computer-readable instructions stored in a memory (e.g., the memory 830) to cause the device 805 to perform various functions (e.g., functions or tasks supporting unequal erasure protection for prioritized data transmission) .

The processor 840 of the device 805 (e.g., controlling the receiver 510, the transmitter 520, or the transceiver 820) may reduce power consumption and increase communications efficiency based on selecting the priority set for the source symbols. In some examples, the processor 840 of the device 805 may reconfigure parameters for recovering the source symbols based on the associated priorities. For example, the processor 840 of the device 805 may turn on one or more processing units for decoding the packets, increase a processing clock, or a similar mechanism within the device 805. As such, when subsequent encoded packets are received, the processor 840 may be ready to respond more efficiently through the reduction of a ramp up in processing power. The improvements in power saving and communications efficiency may further increase battery life at the device 805.

The code 835 may include instructions to implement aspects of the present disclosure, including instructions to support wireless communications. The code 835 may be stored in a non-transitory computer-readable medium such as system memory or other type of memory. In some cases, the code 835 may not be directly executable by the processor 840 but may cause a computer (e.g., when compiled and executed) to perform functions described herein.

FIG. 9 shows a block diagram 900 of a device 905 that supports unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure. The device 905 may be an example of aspects of a second wireless device (e.g., a UE 115 or a base station 105) as described herein. The device 905 may include a receiver 910, a communications manager 915, and a transmitter 920. The device 905 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses) .

The receiver 910 may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to unequal erasure protection for prioritized data transmission, etc. ) . Information may be passed on to other components of the device 905. The receiver 910 may be an example of aspects of the transceiver 1220 described with reference to FIG. 12. The receiver 910 may utilize a single antenna or a set of antennas.

The communications manager 915 may determine one or more priorities associated with a set of source symbols, encode a set of packets according to a fountain code, where each packet of the set of packets is constructed from one or more source symbols of the set of source symbols according to a distribution based on the one or more priorities, and transmit the set of packets to a first wireless device.

The communications manager 915 as described herein may be implemented to realize one or more potential advantages. One implementation may allow the device 905 to save power by communicating with the first wireless device (e.g., a UE 115 or a base station 105 as shown in FIG. 1) more efficiently. For example, the device 905 may improve reliability in communications with a UE 115, as the device 905 may be able to determine the priorities associated with the source symbols and encode the source symbols accordingly to construct the set of packets. The communications manager 915 may be an example of aspects of the communications manager 1210 described herein.

The communications manager 915, or its sub-components, may be implemented in hardware, code (e.g., software or firmware) executed by a processor, or any combination thereof. If implemented in code executed by a processor, the functions of the communications manager 915, or its sub-components may be executed by a general-purpose processor, a DSP, an ASIC, a FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described in the present disclosure.

The communications manager 915, or its sub-components, may be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations by one or more physical components. In some examples, the communications manager 915, or its sub-components, may be a separate and distinct component in accordance with various aspects of the present disclosure. In some examples, the communications manager 915, or its sub-components, may be combined with one or more other hardware components, including but not limited to an I/O component, a transceiver, a network server, another computing device, one or more other components described in the present disclosure, or a combination thereof in accordance with various aspects of the present disclosure.

The transmitter 920 may transmit signals generated by other components of the device 905. In some examples, the transmitter 920 may be collocated with a receiver 910 in a transceiver module. For example, the transmitter 920 may be an example of aspects of the transceiver 1220 described with reference to FIG. 12. The transmitter 920 may utilize a single antenna or a set of antennas.

FIG. 10 shows a block diagram 1000 of a device 1005 that supports unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure. The device 1005 may be an example of aspects of a device 905, or a second wireless device (e.g., a UE 115 or a base station 105) as described herein. The device 1005 may include a receiver 1010, a communications manager 1015, and a transmitter 1035. The device 1005 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses) .

The receiver 1010 may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to unequal erasure protection for prioritized data transmission, etc. ) . Information may be passed on to other components of the device 1005. The receiver 1010 may be an example of aspects of the transceiver 1220 described with reference to FIG. 12. The receiver 1010 may utilize a single antenna or a set of antennas.

The communications manager 1015 may be an example of aspects of the communications manager 915 as described herein. The communications manager 1015 may include a source symbol priority manager 1020, an encoder 1025, and a packet transmission manager 1030. The communications manager 1015 may be an example of aspects of the communications manager 1210 described herein.

The source symbol priority manager 1020 may determine one or more priorities associated with a set of source symbols.

The encoder 1025 may encode a set of packets according to a fountain code, where each packet of the set of packets is constructed from one or more source symbols of the set of source symbols according to a distribution based on the one or more priorities.

The packet transmission manager 1030 may transmit the set of packets to a first wireless device.

The transmitter 1035 may transmit signals generated by other components of the device 1005. In some examples, the transmitter 1035 may be collocated with a receiver 1010 in a transceiver module. For example, the transmitter 1035 may be an example of aspects of the transceiver 1220 described with reference to FIG. 12. The transmitter 1035 may utilize a single antenna or a set of antennas.

FIG. 11 shows a block diagram 1100 of a communications manager 1105 that supports unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure. The communications manager 1105 may be an example of aspects of a communications manager 915, a communications manager 1015, or a communications manager 1210 described herein. The communications manager 1105 may include a source symbol priority manager 1110, an encoder 1115, a packet transmission manager 1120, a feedback receiving manager 1125, and a transmission duration manager 1130. Each of these modules may communicate, directly or indirectly, with one another (e.g., via one or more buses) .

The source symbol priority manager 1110 may determine one or more priorities associated with a set of source symbols.

The encoder 1115 may encode a set of packets according to a fountain code, where each packet of the set of packets is constructed from one or more source symbols of the set of source symbols according to a distribution based on the one or more priorities. In some examples, the encoder 1115 may encode an additional set of packets according to the fountain code, where each packet of the additional set of packets is constructed from one or more additional source symbols according to the distribution based on the one or more priorities.

In some examples, the encoder 1115 may map one or more source symbols of the set of source symbols to each intermediate symbol of a set of intermediate symbols. In some examples, the encoder 1115 may select a degree from a degree distribution associated with the fountain code. In some examples, the encoder 1115 may select one or more intermediate symbols of the set of intermediate symbols based on the selected degree. In some examples, the encoder 1115 may combine the selected one or more intermediate symbols into an encoding symbol, where each packet of the set of packets includes one or more encoding symbols.

In some examples, the encoder 1115 may determine a respective probability associated with each source symbol of the set of source symbols based on a respective priority associated with the source symbol, where selecting the one or more intermediate symbols of the set of intermediate symbols is further based on the respective probabilities associated with the mapped one or more source symbols. In some cases, the set of intermediate symbols include a set of LDPC symbols. In some cases, each source symbol of the set of source symbols is mapped to a quantity of LDPC symbols based on a respective priority associated with the source symbol. In some cases, the selected one or more intermediate symbols are combined based on an exclusive OR logic operation. In some cases, the fountain code includes an LT code, a Raptor code, or both.

The packet transmission manager 1120 may transmit the set of packets to a first wireless device. In some examples, the packet transmission manager 1120 may transmit the additional set of packets to the first wireless device. In some examples, the packet transmission manager 1120 may transmit, to the first wireless device, one or more packets of the set of packets in the remaining portion.

The feedback receiving manager 1125 may receive a feedback message from the first wireless device based on transmitting the set of packets, where the feedback message indicates that one or more source symbols of the set of source symbols were recovered at the first wireless device. In some examples, the feedback receiving manager 1125 may receive a feedback message from the first wireless device based on transmitting the set of packets.

The transmission duration manager 1130 may determine a transmission duration associated with the set of packets, where the set of packets are transmitted to the first wireless device in the transmission duration. In some examples, the transmission duration manager 1130 may determine a remaining portion of the transmission duration after receiving the feedback message. In some examples, the transmission duration manager 1130 may transmit, to the first wireless device, an indication of the transmission duration.

FIG. 12 shows a diagram of a system 1200 including a device 1205 that supports unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure. The device 1205 may be an example of or include the components of device 905, device 1005, or a second wireless device (e.g., a UE 115 or a base station 105) as described herein. The device 1205 may include components for bi-directional voice and data communications including components for transmitting and receiving communications, including a communications manager 1210, a network communications manager 1215, a transceiver 1220, an antenna 1225, memory 1230, a processor 1240, and an inter-station communications manager 1245. These components may be in electronic communication via one or more buses (e.g., bus 1250) .

The communications manager 1210 may determine one or more priorities associated with a set of source symbols, encode a set of packets according to a fountain code, where each packet of the set of packets is constructed from one or more source symbols of the set of source symbols according to a distribution based on the one or more priorities, and transmit the set of packets to a first wireless device.

The network communications manager 1215 may manage communications with the core network (e.g., via one or more wired backhaul links) . For example, the network communications manager 1215 may manage the transfer of data communications for client devices, such as one or more UEs 115.

The transceiver 1220 may communicate bi-directionally, via one or more antennas, wired, or wireless links as described above. For example, the transceiver 1220 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. The transceiver 1220 may also include a modem to modulate the packets and provide the modulated packets to the antennas for transmission, and to demodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 1225. However, in some cases the device may have more than one antenna 1225, which may be capable of concurrently transmitting or receiving multiple wireless transmissions.

The memory 1230 may include RAM, ROM, or a combination thereof. The memory 1230 may store computer-readable code 1235 including instructions that, when executed by a processor (e.g., the processor 1240) cause the device to perform various functions described herein. In some cases, the memory 1230 may contain, among other things, a BIOS which may control basic hardware or software operation such as the interaction with peripheral components or devices.

The processor 1240 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof) . In some cases, the processor 1240 may be configured to operate a memory array using a memory controller. In some cases, a memory controller may be integrated into processor 1240. The processor 1240 may be configured to execute computer-readable instructions stored in a memory (e.g., the memory 1230) to cause the device 1205 to perform various functions (e.g., functions or tasks supporting unequal erasure protection for prioritized data transmission) .

The inter-station communications manager 1245 may manage communications with other base station 105, and may include a controller or scheduler for controlling communications with UEs 115 in cooperation with other base stations 105. For example, the inter-station communications manager 1245 may coordinate scheduling for transmissions to UEs 115 for various interference mitigation techniques such as beamforming or joint transmission. In some examples, the inter-station communications manager 1245 may provide an X2 interface within an LTE/LTE-A wireless communication network technology to provide communication between base stations 105.

The code 1235 may include instructions to implement aspects of the present disclosure, including instructions to support wireless communications. The code 1235 may be stored in a non-transitory computer-readable medium such as system memory or other type of memory. In some cases, the code 1235 may not be directly executable by the processor 1240 but may cause a computer (e.g., when compiled and executed) to perform functions described herein.

FIG. 13 shows a flowchart illustrating a method 1300 that supports unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure. The operations of method 1300 may be implemented by a first wireless device (e.g., a UE 115 or a base station 105) or its components as described herein. For example, the operations of method 1300 may be performed by a communications manager as described with reference to FIGs. 5 through 8. In some examples, a first wireless device may execute a set of instructions to control the functional elements of the first wireless device to perform the functions described below. Additionally or alternatively, a first wireless device may perform aspects of the functions described below using special-purpose hardware.

At 1305, the first wireless device may determine one or more priorities associated with a set of source symbols. The operations of 1305 may be performed according to the methods described herein. In some examples, aspects of the operations of 1305 may be performed by a source symbol priority component as described with reference to FIGs. 5 through 8.

At 1310, the first wireless device may select a priority set of the one or more priorities, where one or more source symbols of the set of source symbols are associated with the priority set. The operations of 1310 may be performed according to the methods described herein. In some examples, aspects of the operations of 1310 may be performed by a priority set selection manager as described with reference to FIGs. 5 through 8.

At 1315, the first wireless device may receive, from a second wireless device, one or more packets encoded according to a fountain code. The operations of 1315 may be performed according to the methods described herein. In some examples, aspects of the operations of 1315 may be performed by a packet receiving manager as described with reference to FIGs. 5 through 8.

At 1320, the first wireless device may decode the one or more packets to recover the one or more source symbols associated with the priority set. The operations of 1320 may be performed according to the methods described herein. In some examples, aspects of the operations of 1320 may be performed by a decoder as described with reference to FIGs. 5 through 8.

FIG. 14 shows a flowchart illustrating a method 1400 that supports unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure. The operations of method 1400 may be implemented by a first wireless device (e.g., a UE 115 or a base station 105) or its components as described herein. For example, the operations of method 1400 may be performed by a communications manager as described with reference to FIGs. 5 through 8. In some examples, a first wireless device may execute a set of instructions to control the functional elements of the first wireless device to perform the functions described below. Additionally or alternatively, a first wireless device may perform aspects of the functions described below using special-purpose hardware.

At 1405, the first wireless device may determine one or more priorities associated with a set of source symbols. The operations of 1405 may be performed according to the methods described herein. In some examples, aspects of the operations of 1405 may be performed by a source symbol priority component as described with reference to FIGs. 5 through 8.

At 1410, the first wireless device may select a priority set of the one or more priorities, where one or more source symbols of the set of source symbols are associated with the priority set. The operations of 1410 may be performed according to the methods described herein. In some examples, aspects of the operations of 1410 may be performed by a priority set selection manager as described with reference to FIGs. 5 through 8.

At 1415, the first wireless device may receive, from a second wireless device, one or more packets encoded according to a fountain code. The operations of 1415 may be performed according to the methods described herein. In some examples, aspects of the operations of 1415 may be performed by a packet receiving manager as described with reference to FIGs. 5 through 8.

At 1420, the first wireless device may decode the one or more packets to recover the one or more source symbols associated with the priority set. The operations of 1420 may be performed according to the methods described herein. In some examples, aspects of the operations of 1420 may be performed by a decoder as described with reference to FIGs. 5 through 8.

At 1425, the first wireless device may determine that the one or more source symbols associated with the priority set of the one or more packets are recovered. The operations of 1425 may be performed according to the methods described herein. In some examples, aspects of the operations of 1425 may be performed by a decoder as described with reference to FIGs. 5 through 8.

At 1430, the first wireless device may transmit a feedback message to the second wireless device based on recovering the one or more source symbols associated with the priority set of the one or more packets. The operations of 1430 may be performed according to the methods described herein. In some examples, aspects of the operations of 1430 may be performed by a feedback manager as described with reference to FIGs. 5 through 8.

FIG. 15 shows a flowchart illustrating a method 1500 that supports unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure. The operations of method 1500 may be implemented by a first wireless device (e.g., a UE 115 or a base station 105) or its components as described herein. For example, the operations of method 1500 may be performed by a communications manager as described with reference to FIGs. 5 through 8. In some examples, a first wireless device may execute a set of instructions to control the functional elements of the first wireless device to perform the functions described below. Additionally or alternatively, a first wireless device may perform aspects of the functions described below using special-purpose hardware.

At 1505, the first wireless device may determine one or more priorities associated with a set of source symbols. The operations of 1505 may be performed according to the methods described herein. In some examples, aspects of the operations of 1505 may be performed by a source symbol priority component as described with reference to FIGs. 5 through 8.

At 1510, the first wireless device may select a priority set of the one or more priorities, where one or more source symbols of the set of source symbols are associated with the priority set. The operations of 1510 may be performed according to the methods described herein. In some examples, aspects of the operations of 1510 may be performed by a priority set selection manager as described with reference to FIGs. 5 through 8.

At 1515, the first wireless device may determine a transmission duration associated with the one or more packets, wherein the one or more packets are received from the second wireless device during the transmission duration. The operations of 1515 may be performed according to the methods described herein. In some examples, aspects of the operations of 1515 may be performed by a transmission duration component as described with reference to FIGs. 5 through 8.

At 1520, the first wireless device may receive, from a second wireless device, one or more packets encoded according to a fountain code. The operations of 1520 may be performed according to the methods described herein. In some examples, aspects of the operations of 1520 may be performed by a packet receiving manager as described with reference to FIGs. 5 through 8.

At 1525, the first wireless device may decode the one or more packets to recover the one or more source symbols associated with the priority set. The operations of 1525 may be performed according to the methods described herein. In some examples, aspects of the operations of 1525 may be performed by a decoder as described with reference to FIGs. 5 through 8.

At 1530, the first wireless device may determine a remaining portion of the transmission duration after recovering the one or more source symbols associated with the priority set. The operations of 1530 may be performed according to the methods described herein. In some examples, aspects of the operations of 1530 may be performed by a transmission duration component as described with reference to FIGs. 5 through 8.

At 1535, the first wireless device may select an additional priority set of the one or more priorities, where one or more additional source symbols of the set of source symbols are associated with the additional priority set. The operations of 1535 may be performed according to the methods described herein. In some examples, aspects of the operations of 1535 may be performed by a priority set selection manager as described with reference to FIGs. 5 through 8.

At 1540, the first wireless device may receive, from the second wireless device, one or more additional packets in the remaining portion. The operations of 1540 may be performed according to the methods described herein. In some examples, aspects of the operations of 1540 may be performed by a packet receiving manager as described with reference to FIGs. 5 through 8.

At 1545, the first wireless device may decode the one or more packets and one or more additional packets to recover the one or more additional source symbols associated with the additional priority set. The operations of 1545 may be performed according to the methods described herein. In some examples, aspects of the operations of 1545 may be performed by a decoder as described with reference to FIGs. 5 through 8.

FIG. 16 shows a flowchart illustrating a method 1600 that supports unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure. The operations of method 1600 may be implemented by a second wireless device (e.g., a UE 115 or a base station 105) or its components as described herein. For example, the operations of method 1600 may be performed by a communications manager as described with reference to FIGs. 9 through 12. In some examples, a second wireless device may execute a set of instructions to control the functional elements of the second wireless device to perform the functions described below. Additionally or alternatively, a second wireless device may perform aspects of the functions described below using special-purpose hardware.

At 1605, the second wireless device may determine one or more priorities associated with a set of source symbols. The operations of 1605 may be performed according to the methods described herein. In some examples, aspects of the operations of 1605 may be performed by a source symbol priority manager as described with reference to FIGs. 9 through 12.

At 1610, the second wireless device may encode a set of packets according to a fountain code, where each packet of the set of packets is constructed from one or more source symbols of the set of source symbols according to a distribution based on the one or more priorities. The operations of 1610 may be performed according to the methods described herein. In some examples, aspects of the operations of 1610 may be performed by an encoder as described with reference to FIGs. 9 through 12.

At 1615, the second wireless device may transmit the set of packets to a first wireless device. The operations of 1615 may be performed according to the methods described herein. In some examples, aspects of the operations of 1615 may be performed by a packet transmission manager as described with reference to FIGs. 9 through 12.

FIG. 17 shows a flowchart illustrating a method 1700 that supports unequal erasure protection for prioritized data transmission in accordance with aspects of the present disclosure. The operations of method 1700 may be implemented by a second wireless device (e.g., a UE 115 or a base station 105) or its components as described herein. For example, the operations of method 1700 may be performed by a communications manager as described with reference to FIGs. 9 through 12. In some examples, a second wireless device may execute a set of instructions to control the functional elements of the second wireless device to perform the functions described below. Additionally or alternatively, a second wireless device may perform aspects of the functions described below using special-purpose hardware.

At 1705, the second wireless device may determine one or more priorities associated with a set of source symbols. The operations of 1705 may be performed according to the methods described herein. In some examples, aspects of the operations of 1705 may be performed by a source symbol priority manager as described with reference to FIGs. 9 through 12.

At 1710, the second wireless device may encode a set of packets according to a fountain code, where each packet of the set of packets is constructed from one or more source symbols of the set of source symbols according to a distribution based on the one or more priorities. The operations of 1710 may be performed according to the methods described herein. In some examples, aspects of the operations of 1710 may be performed by an encoder as described with reference to FIGs. 9 through 12.

At 1715, the second wireless device may transmit the set of packets to a first wireless device. The operations of 1715 may be performed according to the methods described herein. In some examples, aspects of the operations of 1715 may be performed by a packet transmission manager as described with reference to FIGs. 9 through 12.

At 1720, the second wireless device may receive a feedback message from the first wireless device based on transmitting the set of packets, where the feedback message indicates that one or more source symbols of the set of source symbols were recovered at the first wireless device. The operations of 1720 may be performed according to the methods described herein. In some examples, aspects of the operations of 1720 may be performed by a feedback receiving manager as described with reference to FIGs. 9 through 12.

It should be noted that the methods described herein describe possible implementations, and that the operations and the steps may be rearranged or otherwise modified and that other implementations are possible. Further, aspects from two or more of the methods may be combined.

Example 1: A method for wireless communications at a first wireless device, comprising: determining one or more priorities associated with a set of source symbols; selecting a priority set of the one or more priorities, wherein one or more source symbols of the set of source symbols are associated with the priority set; receiving, from a second wireless device, one or more packets encoded according to a fountain code; and decoding the one or more packets to recover the one or more source symbols associated with the priority set.

Example 2: The method of example 1, further comprising: determining that the one or more source symbols associated with the priority set of the one or more packets are recovered; and transmitting a feedback message to the second wireless device based at least in part on recovering the one or more source symbols associated with the priority set of the one or more packets.

Example 3: The method of any of examples 1 or 2, further comprising: receiving, from the second wireless device, one or more additional packets encoded according to the fountain code, wherein the one or more additional packets are received based at least in part on transmission of the feedback message; and decoding the one or more additional packets to recover one or more additional source symbols associated with the priority set.

Example 4: The method of any of examples 1 to 3, further comprising: determining a transmission duration associated with the one or more packets, wherein the one or more packets are received from the second wireless device during the transmission duration; determining a remaining portion of the transmission duration after recovering the one or more source symbols associated with the priority set; selecting an additional priority set of the one or more priorities, wherein one or more additional source symbols of the set of source symbols are associated with the additional priority set; receiving, from the second wireless device, one or more additional packets in the remaining portion; and decoding the one or more packets and one or more additional packets to recover the one or more additional source symbols associated with the additional priority set.

Example 5: The method of any of examples 1 to 4, further comprising: receiving, from the second wireless device, an indication of the transmission duration, wherein the transmission duration is determined based at least in part on receiving the indication.

Example 6: The method of any of examples 1 to 5, wherein the decoding comprises: determining a set of encoding symbols in the received one or more packets; identifying an encoding symbol of the set of encoding symbols that comprises a source symbol of the set of source symbols; determining a priority associated with the source symbol in the identified encoding symbol; and applying a logic operation to one or more encoding symbols of the set of encoding symbols based at least in part on the source symbol in the identified encoding symbol and the determined priority associated with the source symbol.

Example 7: The method of any of examples 1 to 6, wherein the priority associated with the source symbol is in the selected priority set.

Example 8: The method of any of examples 1 to 7, wherein the one or more source symbols associated with the priority set are recovered based at least in part on applying the logic operation.

Example 9: The method of any of examples 1 to 8, wherein the logic operation comprises an exclusive OR logic operation.

Example 10: The method of any of examples 1 to 9, wherein the fountain code comprises a Luby transform (LT) code, a rapid tornado (Raptor) code, or both.

Example 11: An apparatus comprising at least one means for performing a method of any of examples 1 to 10.

Example 12: An apparatus for wireless communications 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 a method of any of examples 1 to 10.

Example 13: A non-transitory computer-readable medium storing code for wireless communications, the code comprising instructions executable by a processor to perform a method of any of examples 1 to 10.

Example 14: A method for wireless communications at a second wireless device, comprising: determining one or more priorities associated with a set of source symbols; encoding a plurality of packets according to a fountain code, wherein each packet of the plurality of packets is constructed from one or more source symbols of the set of source symbols according to a distribution based at least in part on the one or more priorities; and transmitting the plurality of packets to a first wireless device.

Example 15: The method of example 14, further comprising: receiving a feedback message from the first wireless device based at least in part on transmitting the plurality of packets, wherein the feedback message indicates that one or more source symbols of the set of source symbols were recovered at the first wireless device.

Example 16: The method of any of examples 14 or 15, further comprising: encoding an additional plurality of packets according to the fountain code, wherein each packet of the additional plurality of packets is constructed from one or more additional source symbols according to the distribution based at least in part on the one or more priorities; and transmitting the additional plurality of packets to the first wireless device.

Example 17: The method of any of examples 14 to 16, further comprising: determining a transmission duration associated with the plurality of packets, wherein the plurality of packets are transmitted to the first wireless device in the transmission duration.

Example 18: The method of any of examples 14 to 17, further comprising: receiving a feedback message from the first wireless device based at least in part on transmitting the plurality of packets; determining a remaining portion of the transmission duration after receiving the feedback message; and transmitting, to the first wireless device, one or more packets of the plurality of packets in the remaining portion.

Example 19: The method of any of example 14 to 18, further comprising: transmitting, to the first wireless device, an indication of the transmission duration.

Example 20: The method of any of examples 14 to 19, wherein the encoding comprises: mapping one or more source symbols of the set of source symbols to each intermediate symbol of a set of intermediate symbols; selecting a degree from a degree distribution associated with the fountain code; selecting one or more intermediate symbols of the set of intermediate symbols based at least in part on the selected degree; and combining the selected one or more intermediate symbols into an encoding symbol, wherein each packet of the plurality of packets comprises one or more encoding symbols.

Example 21: The method of any of examples 14 to 20, wherein: the set of intermediate symbols comprise a set of low-density parity-check (LDPC) symbols; and each source symbol of the set of source symbols is mapped to a quantity of LDPC symbols based at least in part on a respective priority associated with the source symbol.

Example 22: The method of any of examples 14 to 21, wherein the encoding comprises: determining a respective probability associated with each source symbol of the set of source symbols based at least in part on a respective priority associated with the source symbol, wherein selecting the one or more intermediate symbols of the set of intermediate symbols is further based at least in part on the respective probabilities associated with the mapped one or more source symbols.

Example 23: The method of any of examples 14 to 22, wherein the selected one or more intermediate symbols are combined based at least in part on an exclusive OR logic operation.

Example 24: The method of any of examples 14 to 23, wherein the fountain code comprises a Luby transform (LT) code, a rapid tornado (Raptor) code, or both.

Example 25: An apparatus comprising at least one means for performing a method of any of examples 14 to 24.

Example 26: An apparatus for wireless communications 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 a method of any of examples 14 to 24.

Example 27: A non-transitory computer-readable medium storing code for wireless communications, the code comprising instructions executable by a processor to perform a method of any of examples 14 to 24.

Although aspects of an LTE, LTE-A, LTE-A Pro, or NR system may be described for purposes of example, and LTE, LTE-A, LTE-A Pro, or NR terminology may be used in much of the description, the techniques described herein are applicable beyond LTE, LTE-A, LTE-A Pro, or NR networks. For example, the described techniques may be applicable to various other wireless communications systems such as Ultra Mobile Broadband (UMB) , Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi) , IEEE 802.16 (WiMAX) , IEEE 802.20, Flash-OFDM, as well as other systems and radio technologies not explicitly mentioned herein.

Information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

The various illustrative blocks and components described in connection with the disclosure herein may be implemented or performed with a general-purpose processor, a DSP, an ASIC, a CPU, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but in the alternative, the processor may be any processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration) .

The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Other examples and implementations are within the scope of the disclosure and appended claims. For example, due to the nature of software, functions described herein may be implemented using software executed by a processor, hardware, firmware, hardwiring, or combinations of any of these. Features implementing functions may also be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations.

Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A non-transitory storage medium may be any available medium that may be accessed by a general-purpose or special-purpose computer. By way of example, and not limitation, non-transitory computer-readable media may include RAM, ROM, electrically erasable programmable ROM (EEPROM) , flash memory, compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that may be used to carry or store desired program code means in the form of instructions or data structures and that may be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor. Also, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL) , or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of computer-readable medium. Disk and disc, as used herein, include CD, laser disc, optical disc, digital versatile disc (DVD) , floppy disk and Blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above are also included within the scope of computer-readable media.

As used herein, including in the claims, “or” as used in a list of items (e.g., a list of items prefaced by a phrase such as “at least one of” or “one or more of” ) indicates an inclusive list such that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C) . Also, as used herein, the phrase “based on” shall not be construed as a reference to a closed set of conditions. For example, an example step that is described as “based on condition A” may be based on both a condition A and a condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase “based on” shall be construed in the same manner as the phrase “based at least in part on. ”

In the appended figures, similar components or features may have the same reference label. Further, various components of the same type may be distinguished by following the reference label by a dash and a second label that distinguishes among the similar components. If just the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the second reference label, or other subsequent reference label.

The description set forth herein, in connection with the appended drawings, describes example configurations and does not represent all the examples that may be implemented or that are within the scope of the claims. The term “example” used herein means “serving as an example, instance, or illustration, ” and not “preferred” or “advantageous over other examples. ” The detailed description includes specific details for the purpose of providing an understanding of the described techniques. These techniques, however, may be practiced without these specific details. In some instances, known structures and devices are shown in block diagram form in order to avoid obscuring the concepts of the described examples.

The description herein is provided to enable a person having ordinary skill in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to a person having ordinary skill in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the disclosure is not limited to the examples and designs described herein, but is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.

Claims

A method for wireless communications at a first wireless device, comprising:

determining one or more priorities associated with a set of source symbols;

selecting a priority set of the one or more priorities, wherein one or more source symbols of the set of source symbols are associated with the priority set;

receiving, from a second wireless device, one or more packets encoded according to a fountain code; and

decoding the one or more packets to recover the one or more source symbols associated with the priority set.
The method of claim 1, further comprising:

determining that the one or more source symbols associated with the priority set of the one or more packets are recovered; and

transmitting a feedback message to the second wireless device based at least in part on recovering the one or more source symbols associated with the priority set of the one or more packets.
The method of claim 2, further comprising:

receiving, from the second wireless device, one or more additional packets encoded according to the fountain code, wherein the one or more additional packets are received based at least in part on transmission of the feedback message; and

decoding the one or more additional packets to recover one or more additional source symbols associated with the priority set.
The method of claim 1, further comprising:

determining a transmission duration associated with the one or more packets, wherein the one or more packets are received from the second wireless device during the transmission duration;

determining a remaining portion of the transmission duration after recovering the one or more source symbols associated with the priority set;

selecting an additional priority set of the one or more priorities, wherein one or more additional source symbols of the set of source symbols are associated with the additional priority set;

receiving, from the second wireless device, one or more additional packets in the remaining portion; and

decoding the one or more packets and one or more additional packets to recover the one or more additional source symbols associated with the additional priority set.
The method of claim 4, further comprising:

receiving, from the second wireless device, an indication of the transmission duration, wherein the transmission duration is determined based at least in part on receiving the indication.
The method of claim 1, wherein the decoding comprises:

determining a set of encoding symbols in the received one or more packets;

identifying an encoding symbol of the set of encoding symbols that comprises a source symbol of the set of source symbols;

determining a priority associated with the source symbol in the identified encoding symbol; and

applying a logic operation to one or more encoding symbols of the set of encoding symbols based at least in part on the source symbol in the identified encoding symbol and the determined priority associated with the source symbol.
The method of claim 6, wherein the priority associated with the source symbol is in the selected priority set.
The method of claim 6, wherein the one or more source symbols associated with the priority set are recovered based at least in part on applying the logic operation.
The method of claim 6, wherein the logic operation comprises an exclusive OR logic operation.
The method of claim 1, wherein the fountain code comprises a Luby transform (LT) code, a rapid tornado (Raptor) code, or both.
A method for wireless communications at a second wireless device, comprising:

determining one or more priorities associated with a set of source symbols;

encoding a plurality of packets according to a fountain code, wherein each packet of the plurality of packets is constructed from one or more source symbols of the set of source symbols according to a distribution based at least in part on the one or more priorities; and

transmitting the plurality of packets to a first wireless device.
The method of claim 11, further comprising:

receiving a feedback message from the first wireless device based at least in part on transmitting the plurality of packets, wherein the feedback message indicates that one or more source symbols of the set of source symbols were recovered at the first wireless device.
The method of claim 12, further comprising:

encoding an additional plurality of packets according to the fountain code, wherein each packet of the additional plurality of packets is constructed from one or more additional source symbols according to the distribution based at least in part on the one or more priorities; and

transmitting the additional plurality of packets to the first wireless device.
The method of claim 11, further comprising:

determining a transmission duration associated with the plurality of packets, wherein the plurality of packets are transmitted to the first wireless device in the transmission duration.
The method of claim 14, further comprising:

receiving a feedback message from the first wireless device based at least in part on transmitting the plurality of packets;

determining a remaining portion of the transmission duration after receiving the feedback message; and

transmitting, to the first wireless device, one or more packets of the plurality of packets in the remaining portion.
The method of claim 14, further comprising:

transmitting, to the first wireless device, an indication of the transmission duration.
The method of claim 11, wherein the encoding comprises:

mapping one or more source symbols of the set of source symbols to each intermediate symbol of a set of intermediate symbols;

selecting a degree from a degree distribution associated with the fountain code;

selecting one or more intermediate symbols of the set of intermediate symbols based at least in part on the selected degree; and

combining the selected one or more intermediate symbols into an encoding symbol, wherein each packet of the plurality of packets comprises one or more encoding symbols.
The method of claim 17, wherein:

the set of intermediate symbols comprise a set of low-density parity-check (LDPC) symbols; and

each source symbol of the set of source symbols is mapped to a quantity of LDPC symbols based at least in part on a respective priority associated with the source symbol.
The method of claim 17, wherein the encoding comprises:

determining a respective probability associated with each source symbol of the set of source symbols based at least in part on a respective priority associated with the source symbol, wherein selecting the one or more intermediate symbols of the set of intermediate symbols is further based at least in part on the respective probabilities associated with the mapped one or more source symbols.
The method of claim 17, wherein the selected one or more intermediate symbols are combined based at least in part on an exclusive OR logic operation.
The method of claim 11, wherein the fountain code comprises a Luby transform (LT) code, a rapid tornado (Raptor) code, or both.
An apparatus for wireless communications at a first wireless 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:

determine one or more priorities associated with a set of source symbols;

select a priority set of the one or more priorities, wherein one or more source symbols of the set of source symbols are associated with the priority set;

receive, from a second wireless device, one or more packets encoded according to a fountain code; and

decode the one or more packets to recover the one or more source symbols associated with the priority set.
The apparatus of claim 22, wherein the instructions are further executable by the processor to cause the apparatus to:

determine that the one or more source symbols associated with the priority set of the one or more packets are recovered; and

transmit a feedback message to the second wireless device based at least in part on recovering the one or more source symbols associated with the priority set of the one or more packets.
The apparatus of claim 23, wherein the instructions are further executable by the processor to cause the apparatus to:

receive, from the second wireless device, one or more additional packets encoded according to the fountain code, wherein the one or more additional packets are received based at least in part on transmission of the feedback message; and

decode the one or more additional packets to recover one or more additional source symbols associated with the priority set.
The apparatus of claim 22, wherein the instructions are further executable by the processor to cause the apparatus to:

determine a transmission duration associated with the one or more packets, wherein the one or more packets are received from the second wireless device during the transmission duration;

determine a remaining portion of the transmission duration after recovering the one or more source symbols associated with the priority set;

select an additional priority set of the one or more priorities, wherein one or more additional source symbols of the set of source symbols are associated with the additional priority set;

receive, from the second wireless device, one or more additional packets in the remaining portion; and

decode the one or more packets and one or more additional packets to recover the one or more additional source symbols associated with the additional priority set.
The apparatus of claim 25, wherein the instructions are further executable by the processor to cause the apparatus to:

receive, from the second wireless device, an indication of the transmission duration, wherein the transmission duration is determined based at least in part on receiving the indication.
The apparatus of claim 22, wherein the instructions are further executable by the processor to cause the apparatus to:

determine a set of encoding symbols in the received one or more packets;

identify an encoding symbol of the set of encoding symbols that comprises a source symbol of the set of source symbols;

determine a priority associated with the source symbol in the identified encoding symbol; and

apply a logic operation to one or more encoding symbols of the set of encoding symbols based at least in part on the source symbol in the identified encoding symbol and the determined priority associated with the source symbol.
The apparatus of claim 27, wherein the priority associated with the source symbol is in the selected priority set.
The apparatus of claim 27, wherein the one or more source symbols associated with the priority set are recovered based at least in part on applying the logic operation.
The apparatus of claim 27, wherein the logic operation comprises an exclusive OR logic operation.
The apparatus of claim 22, wherein the fountain code comprises a Luby transform (LT) code, a rapid tornado (Raptor) code, or both.
An apparatus for wireless communications at a second wireless 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:

determine one or more priorities associated with a set of source symbols;

encode a plurality of packets according to a fountain code, wherein each packet of the plurality of packets is constructed from one or more source symbols of the set of source symbols according to a distribution based at least in part on the one or more priorities; and

transmit the plurality of packets to a first wireless device.
The apparatus of claim 32, wherein the instructions are further executable by the processor to cause the apparatus to:

receive a feedback message from the first wireless device based at least in part on transmitting the plurality of packets, wherein the feedback message indicates that one or more source symbols of the set of source symbols were recovered at the first wireless device.
The apparatus of claim 33, wherein the instructions are further executable by the processor to cause the apparatus to:

encode an additional plurality of packets according to the fountain code, wherein each packet of the additional plurality of packets is constructed from one or more additional source symbols according to the distribution based at least in part on the one or more priorities; and

transmit the additional plurality of packets to the first wireless device.
The apparatus of claim 32, wherein the instructions are further executable by the processor to cause the apparatus to:

determine a transmission duration associated with the plurality of packets, wherein the plurality of packets are transmitted to the first wireless device in the transmission duration.
The apparatus of claim 35, wherein the instructions are further executable by the processor to cause the apparatus to:

receive a feedback message from the first wireless device based at least in part on transmitting the plurality of packets;

determine a remaining portion of the transmission duration after receiving the feedback message; and

transmit, to the first wireless device, one or more packets of the plurality of packets in the remaining portion.
The apparatus of claim 35, wherein the instructions are further executable by the processor to cause the apparatus to:

transmit, to the first wireless device, an indication of the transmission duration.
The apparatus of claim 32, wherein the instructions are further executable by the processor to cause the apparatus to:

map one or more source symbols of the set of source symbols to each intermediate symbol of a set of intermediate symbols;

select a degree from a degree distribution associated with the fountain code;

select one or more intermediate symbols of the set of intermediate symbols based at least in part on the selected degree; and

combine the selected one or more intermediate symbols into an encoding symbol, wherein each packet of the plurality of packets comprises one or more encoding symbols.
The apparatus of claim 38, wherein:

the set of intermediate symbols comprise a set of low-density parity-check (LDPC) symbols; and

each source symbol of the set of source symbols is mapped to a quantity of LDPC symbols based at least in part on a respective priority associated with the source symbol.
The apparatus of claim 38, wherein the instructions are further executable by the processor to cause the apparatus to:

determine a respective probability associated with each source symbol of the set of source symbols based at least in part on a respective priority associated with the source symbol, wherein selecting the one or more intermediate symbols of the set of intermediate symbols is further based at least in part on the respective probabilities associated with the mapped one or more source symbols.
The apparatus of claim 38, wherein the selected one or more intermediate symbols are combined based at least in part on an exclusive OR logic operation.
The apparatus of claim 32, wherein the fountain code comprises a Luby transform (LT) code, a rapid tornado (Raptor) code, or both.
An apparatus for wireless communications at a first wireless device, comprising:

means for determining one or more priorities associated with a set of source symbols;

means for selecting a priority set of the one or more priorities, wherein one or more source symbols of the set of source symbols are associated with the priority set;

means for receiving, from a second wireless device, one or more packets encoded according to a fountain code; and

means for decoding the one or more packets to recover the one or more source symbols associated with the priority set.
An apparatus for wireless communications at a second wireless device, comprising:

means for determining one or more priorities associated with a set of source symbols;

means for encoding a plurality of packets according to a fountain code, wherein each packet of the plurality of packets is constructed from one or more source symbols of the set of source symbols according to a distribution based at least in part on the one or more priorities; and

means for transmitting the plurality of packets to a first wireless device.
A non-transitory computer-readable medium storing code for wireless communications at a first wireless device, the code comprising instructions executable by a processor to:

determine one or more priorities associated with a set of source symbols;

select a priority set of the one or more priorities, wherein one or more source symbols of the set of source symbols are associated with the priority set;

receive, from a second wireless device, one or more packets encoded according to a fountain code; and

decode the one or more packets to recover the one or more source symbols associated with the priority set.
A non-transitory computer-readable medium storing code for wireless communications at a second wireless device, the code comprising instructions executable by a processor to:

determine one or more priorities associated with a set of source symbols;

encode a plurality of packets according to a fountain code, wherein each packet of the plurality of packets is constructed from one or more source symbols of the set of source symbols according to a distribution based at least in part on the one or more priorities; and

transmit the plurality of packets to a first wireless device.