WO2021179151A1

WO2021179151A1 - Encoding scheme selection for wireless transmissions

Info

Publication number: WO2021179151A1
Application number: PCT/CN2020/078511
Authority: WO
Inventors: Jian Li; Changlong Xu; Kangqi LIU; Liangming WU; Hao Xu
Original assignee: Qualcomm Incorporated
Priority date: 2020-03-10
Filing date: 2020-03-10
Publication date: 2021-09-16

Abstract

Methods, systems, and devices for wireless communications are described. A transmitting device (e. g., a base station or a user equipment (UE) ) may identify a set of source symbols for a wireless transmission and determine a quantity of source symbols. The transmitting device may select an encoding scheme based on whether the quantity of source symbols in the set is less than a threshold quantity. The selected encoding scheme may be one of a set of at least two candidate encoding schemes, and different candidate encoding schemes may have different performance characteristics. The transmitting device may generate a set of encoded symbols based on the selected encoding scheme and transmit the set of encoded symbols.

Description

ENCODING SCHEME SELECTION FOR WIRELESS TRANSMISSIONS

FIELD OF TECHNOLOGY

The following relates generally to wireless communications and more specifically to encoding scheme selection for wireless 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) .

Information transmitted between network nodes may be encoded to improve the reliability of the transmitted information. For example, an encoding scheme (algorithm) 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 schemes may include the use of or otherwise be based on 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 encoding scheme selection for wireless transmissions. Generally, the described techniques may provide efficiency through one or more tradeoffs between various performance considerations, such as complexity and overhead considerations, for multiple encoding schemes. For example, for a given failure probability, one encoding scheme may have lower overhead than another encoding scheme but may involve more complex encoding and decoding operations. When a set of source symbols for a wireless transmission is small (includes relatively few source symbols) , the extra overhead associated with the less complex encoding scheme may correspond to a relatively large percentage of the total transmitted (encoded) symbols, and a transmitting device may select to use the more complex encoding scheme. Conversely, when a set of source symbols for another wireless transmission is large (includes relatively may source symbols) , the extra overhead associated with the less complex encoding scheme may correspond to a relatively small percentage of the total transmitted (encoded) symbols, and a transmitting device may select to use the less complex encoding scheme.

Thus, as described herein, a transmitting device may identify a set of source symbols for a wireless transmission, and then the transmitting device may select between a first encoding scheme and a second encoding scheme based on a quantity of source symbols to be encoded for the wireless transmission. For example, the transmitting device may select and use a more complex but lower overhead encoding scheme if the quantity of source symbols is below a threshold quantity, and the transmitting device may select and use a more complex but lower overhead encoding scheme if the quantity of source symbols is greater than or equal to the threshold quantity. In some cases, one or both of the candidate encoding schemes may be fountain codes, such as rapid tornado (Raptor) codes and RaptorQ codes.

A method of wireless communication is described. The method may include identifying a set of source symbols for a wireless transmission, selecting between a first encoding scheme and a second encoding scheme based on whether a quantity of source symbols in the set is less than a threshold quantity, where the first encoding scheme has a higher overhead than the second encoding scheme, generating a set of encoded symbols based on the selected encoding scheme, and transmitting the set of encoded symbols.

An apparatus for wireless communication 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 identify a set of source symbols for a wireless transmission, select between a first encoding scheme and a second encoding scheme based on whether a quantity of source symbols in the set is less than a threshold quantity, where the first encoding scheme has a higher overhead than the second encoding scheme, generate a set of encoded symbols based on the selected encoding scheme, and transmit the set of encoded symbols.

Another apparatus for wireless communication is described. The apparatus may include means for identifying a set of source symbols for a wireless transmission, selecting between a first encoding scheme and a second encoding scheme based on whether a quantity of source symbols in the set is less than a threshold quantity, where the first encoding scheme has a higher overhead than the second encoding scheme, generating a set of encoded symbols based on the selected encoding scheme, and transmitting the set of encoded symbols.

A non-transitory computer-readable medium storing code for wireless communication is described. The code may include instructions executable by a processor to identify a set of source symbols for a wireless transmission, select between a first encoding scheme and a second encoding scheme based on whether a quantity of source symbols in the set is less than a threshold quantity, where the first encoding scheme has a higher overhead than the second encoding scheme, generate a set of encoded symbols based on the selected encoding scheme, and transmit the set of encoded symbols.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, selecting between the first encoding scheme and the second encoding scheme may include operations, features, means, or instructions for determining that the quantity of source symbols in the set may be less than the threshold quantity, and selecting the second encoding scheme to generate the set of encoded symbols.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, selecting between the first encoding scheme and the second encoding scheme may include operations, features, means, or instructions for determining that the quantity of source symbols in the set may be greater than the threshold quantity, and selecting the first encoding scheme to generate the set of encoded symbols.

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 a receiver, an indication of the selected encoding scheme.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the first encoding scheme may be associated with a Raptor code and the second encoding scheme may be associated with a RaptorQ code. In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the first encoding scheme may be based on a first Galois Field and the second encoding scheme may be based on a second Galois Field, a size of the second Galois Field being greater than a size of the first Galois Field.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the size of the first Galois Field may be 2 and the size of the second Galois Field may be 256. In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the first encoding scheme may be associated with a first rateless code and the second encoding scheme may be associated with a second rateless code.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the first encoding scheme and the second encoding scheme may be configured to may have a same failure probability, and where the first encoding scheme may have the higher overhead than the second encoding scheme when the second encoding scheme may be configured to may have the same failure probability.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the wireless transmission may be associated with one or more multimedia broadcast multicast service (MBMS) applications. In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, operations, features, means, or instructions for generating the set of encoded symbols may include operations, features, means, or instructions for generating the set of encoded symbols at an application layer of a protocol stack for a device or apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a system for wireless communications that supports encoding scheme selection for wireless transmissions in accordance with aspects of the present disclosure.

FIG. 2 illustrates an example of an encoding scheme that supports encoding scheme selection for wireless transmissions in accordance with aspects of the present disclosure.

FIG. 3 illustrates an example of a process flow that supports encoding scheme selection for wireless transmissions in accordance with aspects of the present disclosure.

FIGs. 4 and 5 show block diagrams of devices that support encoding scheme selection for wireless transmissions in accordance with aspects of the present disclosure.

FIG. 6 shows a block diagram of a communications manager that supports encoding scheme selection for wireless transmissions in accordance with aspects of the present disclosure.

FIG. 7 shows a diagram of a system including a user equipment (UE) that supports encoding scheme selection for wireless transmissions in accordance with aspects of the present disclosure.

FIG. 8 shows a diagram of a system including a base station that supports encoding scheme selection for wireless transmissions in accordance with aspects of the present disclosure.

FIGs. 9 through 11 show flowcharts illustrating methods that support encoding scheme selection for wireless transmissions in accordance with aspects of the present disclosure.

DETAILED DESCRIPTION

In some wireless communications systems, a network node (e.g., a user equipment (UE) , a base station, or another wireless device) may encode source information (e.g., packets) and then transmit the encoded information, where the encoding may improve the reliability with which a destination node may recover the original source information (e.g. through redundancy or other mechanisms) . The source information may be represented by a set of source symbols, and based on the operative encoding scheme, an encoder may generate a corresponding set of encoded symbols (which may be transmitted by a transmitting device and received by a receiving device) .

Some examples of codes for use with encoding schemes may include fountain codes, such as Luby transform (LT) codes or rapid tornado (Raptor) codes. A fountain code may be an example of a type of rateless code, which may mean that the code is not associated with any fixed code rate (which may alternatively be referred to as coding rate) . For example, a set of source symbols may be encoded to generate any quantity of encoded symbols, and the source symbols may be recovered based on any sufficiently large group of encoded symbols-that is, it may not matter which particular encoded symbols are received by a receiving device, so long as a sufficient quantity of encoded symbols are received.

In some examples, encoding the source symbols using a fountain code may include combining information related to one or more source symbols into each encoded symbol. Encoded symbols corresponding to (generated based on) a set of source symbols may be transmitted from a first node or device (which may be referred to as an input node) of a network to a second node or device (which may be referred to as an output node) . In some examples, one or more encoded symbols may be lost or experience interference due to the transmission environment of the channel. Thus, the output node may receive only a subset of the encoded symbols that are transmitted via the channel, or the output node may receive some of the encoded symbols with a low signal-to-noise (SNR) level. Based on the use of a fountain code for the encoding, however, and the combining of information related to one or more source symbols into each encoded symbol, the output node may nevertheless be able recover the set of source symbols based on decoding the encoded symbols that the output node received.

K may be used herein to represent the quantity of source symbols in a set that are encoded by a transmitting device (node) in accordance with an encoding scheme, and N may be used herein to represent the quantity of corresponding encoded symbols that a receiving device (node) must receive in order to recover the quantity of source symbols with a given likelihood (which may be referred to or otherwise expressed as a failure probability) . A difference between N and K (that is, the quantity N-K) may correspond to an overhead for the encoding scheme.

Some codes, such as fountain codes for example, may use a corresponding finite set (alternatively, finite field) , such as a Galois Field (GF) , which may be of a specific size. For example, a Raptor code may be a first type of fountain code and may have a GF of size two (2) , which may mean a finite set of two elements and may be denoted as GF (2) . As another example, a RaptorQ code may be a second type of fountain code and may have a GF of size two-hundred and fifty-six (256) , which may mean a finite set of 256 elements and may be denoted as GF (256) . In some cases, a larger finite set for a type of code may correspond to increased encoding and decoding complexity for corresponding encoding and decoding schemes.

Different encoding schemes may use different types of codes and may present various performance tradeoffs, such as complexity and overhead tradeoffs. As described herein, a transmitting device may use different encoding schemes for different sets of source symbols based on such tradeoffs. For example, a transmitting device may be configured to switch between a first encoding scheme and a second encoding scheme based on a quantity of source symbols included in a set. The transmitting device may select and use a more complex but lower overhead encoding scheme if the quantity of source symbols is below a threshold quantity, and the transmitting device may select and use a more complex but lower overhead encoding scheme if the quantity of source symbols is greater than or equal to the threshold quantity. In some cases, one or both of the candidate encoding schemes may be fountain codes, such as Raptor codes and RaptorQ codes, though other codes and types of codes are possible.

When a set of source symbols for a wireless transmission is small (e.g., K smaller than a threshold) , the extra overhead associated with the less complex encoding scheme (relatively large value of N-K) may correspond to a relatively large percentage of the total transmitted symbols, and thus-on balance-the extra complexity associated with the more complex encoding scheme may be beneficial (e.g., may conserve spectral or other system resources, among other benefits that may be appreciated by one or ordinary skill in the art) . But when a set of source symbols for another wireless transmission is large (e.g., K larger than the threshold) , the extra overhead associated with the less complex encoding scheme may correspond to a relatively small percentage of the total transmitted symbols, and thus-on balance-the reduced complexity associated with the less complex encoding scheme may be beneficial (e.g., may conserve processing or other system resources, among other benefits that may be appreciated by one or ordinary skill in the art) . Thus, encoding scheme selection as described herein may beneficially improve efficiency and reliability of communications.

Aspects of the disclosure are initially described in the context of wireless communications systems. Aspects of the disclosure are described in the context of diagrams that explain the coding scheme and a process flow. Aspects of the disclosure are further illustrated by and described with reference to apparatus diagrams, system diagrams, and flowcharts that relate to encoding scheme selection for wireless transmissions.

FIG. 1 illustrates an example of a wireless communications system 100 that supports encoding scheme selection for wireless transmissions 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.

In some examples (e.g., in a carrier aggregation configuration) , a carrier may also have acquisition signaling or control signaling that coordinates operations for other carriers. A carrier may be associated with a frequency channel (e.g., an evolved universal mobile telecommunication system terrestrial radio access (E-UTRA) absolute radio frequency channel number (EARFCN) ) and may be positioned according to a channel raster for discovery by the UEs 115. A carrier may be operated in a standalone mode where initial acquisition and connection may be conducted by the UEs 115 via the carrier, or the carrier may be operated in a non-standalone mode where a connection is anchored using a different carrier (e.g., of the same or a different radio access technology) .

The communication links 125 shown in the wireless communications system 100 may include uplink transmissions from a UE 115 to a base station 105, or downlink transmissions from a base station 105 to a UE 115. Carriers may carry downlink or uplink communications (e.g., in an FDD mode) or may be configured to carry downlink and uplink communications (e.g., in a TDD mode) .

A carrier may be associated with a particular bandwidth of the radio frequency spectrum, and in some examples the carrier bandwidth may be referred to as a “system bandwidth” of the carrier or the wireless communications system 100. For example, the carrier bandwidth may be one of a number of determined bandwidths for carriers of a particular radio access technology (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 megahertz (MHz) ) . Devices of the wireless communications system 100 (e.g., the base stations 105, the UEs 115, or both) may have hardware configurations that support communications over a particular carrier bandwidth or may be configurable to support communications over one of a set of carrier bandwidths. In some examples, the wireless communications system 100 may include base stations 105 or UEs 115 that support simultaneous communications via carriers associated with multiple carrier bandwidths. In some examples, each served UE 115 may be configured for operating over portions (e.g., a sub-band, a BWP) or all of a carrier bandwidth.

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.

One or more numerologies for a carrier may be supported, where a numerology may include a subcarrier spacing (Δf) and a cyclic prefix. A carrier may be divided into one or more BWPs having the same or different numerologies. In some examples, a UE 115 may be configured with multiple BWPs. In some examples, a single BWP for a carrier may be active at a given time and communications for the UE 115 may be restricted to one or more active BWPs.

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.

Each base station 105 may provide communication coverage via one or more cells, for example a macro cell, a small cell, a hot spot, or other types of cells, or any combination thereof. The term “cell” may refer to a logical communication entity used for communication with a base station 105 (e.g., over a carrier) and may be associated with an identifier for distinguishing neighboring cells (e.g., a physical cell identifier (PCID) , a virtual cell identifier (VCID) , or others) . In some examples, a cell may also refer to a geographic coverage area 110 or a portion of a geographic coverage area 110 (e.g., a sector) over which the logical communication entity operates. Such cells may range from smaller areas (e.g., a structure, a subset of structure) to larger areas depending on various factors such as the capabilities of the base station 105. For example, a cell may be or include a building, a subset of a building, or exterior spaces between or overlapping with geographic coverage areas 110, among other examples.

A macro cell generally covers a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by the UEs 115 with service subscriptions with the network provider supporting the macro cell. A small cell may be associated with a lower-powered base station 105, as compared with a macro cell, and a small cell may operate in the same or different (e.g., licensed, unlicensed) frequency bands as macro cells. Small cells may provide unrestricted access to the UEs 115 with service subscriptions with the network provider or may provide restricted access to the UEs 115 having an association with the small cell (e.g., the UEs 115 in a closed subscriber group (CSG) , the UEs 115 associated with users in a home or office) . A base station 105 may support one or multiple cells and may also support communications over the one or more cells using one or multiple component carriers.

In some examples, a carrier may support multiple cells, and different cells may be configured according to different protocol types (e.g., MTC, narrowband IoT (NB-IoT) , enhanced mobile broadband (eMBB) ) that may provide access for different types of devices.

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 support synchronous or asynchronous operation. For synchronous operation, the base stations 105 may have similar frame timings, and transmissions from different base stations 105 may be approximately aligned in time. For asynchronous operation, the base stations 105 may have different frame timings, and transmissions from different base stations 105 may, in some examples, not be aligned in time. The techniques described herein may be used for either synchronous or asynchronous operations.

Some UEs 115, such as MTC or IoT devices, may be low cost or low complexity devices and may provide for automated communication between machines (e.g., via Machine-to-Machine (M2M) communication) . M2M communication or MTC may refer to data communication technologies that allow devices to communicate with one another or a base station 105 without human intervention. In some examples, M2M communication or MTC may include communications from devices that integrate sensors or meters to measure or capture information and relay such information to a central server or application program that makes use of the information or presents the information to humans interacting with the application program. Some UEs 115 may be designed to collect information or enable automated behavior of machines or other devices. Examples of applications for MTC devices include smart metering, inventory monitoring, water level monitoring, equipment monitoring, healthcare monitoring, wildlife monitoring, weather and geological event monitoring, fleet management and tracking, remote security sensing, physical access control, and transaction-based business charging.

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 also operate in a super high frequency (SHF) region using frequency bands from 3 GHz to 30 GHz, also known as the centimeter band, or in an extremely high frequency (EHF) region of the spectrum (e.g., from 30 GHz to 300 GHz) , also known as the millimeter band. In some examples, the wireless communications system 100 may support millimeter wave (mmW) communications between the UEs 115 and the base stations 105, and EHF antennas of the respective devices may be smaller and more closely spaced than UHF antennas. In some examples, this may facilitate use of antenna arrays within a device. The propagation of EHF transmissions, however, may be subject to even greater atmospheric attenuation and shorter range than SHF or UHF transmissions. The techniques disclosed herein may be employed across transmissions that use one or more different frequency regions, and designated use of bands across these frequency regions may differ by country or regulating body.

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) .

A base station 105 or a UE 115 may use beam sweeping techniques as part of beam forming operations. For example, a base station 105 may use multiple antennas or antenna arrays (e.g., antenna panels) to conduct beamforming operations for directional communications with a UE 115. Some signals (e.g., synchronization signals, reference signals, beam selection signals, or other control signals) may be transmitted by a base station 105 multiple times in different directions. For example, the base station 105 may transmit a signal according to different beamforming weight sets associated with different directions of transmission. Transmissions in different beam directions may be used to identify (e.g., by a transmitting device, such as a base station 105, or by a receiving device, such as a UE 115) a beam direction for later transmission or reception by the base station 105.

Some signals, such as data signals associated with a particular receiving device, may be transmitted by a base station 105 in a single beam direction (e.g., a direction associated with the receiving device, such as a UE 115) . In some examples, the beam direction associated with transmissions along a single beam direction may be determined based on a signal that was transmitted in one or more beam directions. For example, a UE 115 may receive one or more of the signals transmitted by the base station 105 in different directions and may report to the base station 105 an indication of the signal that the UE 115 received with a highest signal quality or an otherwise acceptable signal quality.

In some examples, transmissions by a device (e.g., by a base station 105 or a UE 115) may be performed using multiple beam directions, and the device may use a combination of digital precoding or radio frequency beamforming to generate a combined beam for transmission (e.g., from a base station 105 to a UE 115) . The UE 115 may report feedback that indicates precoding weights for one or more beam directions, and the feedback may correspond to a configured number of beams across a system bandwidth or one or more sub-bands. The base station 105 may transmit a reference signal (e.g., a cell-specific reference signal (CRS) , a channel state information reference signal (CSI-RS) ) , which may be precoded or unprecoded. The UE 115 may provide feedback for beam selection, which may be a precoding matrix indicator (PMI) or codebook-based feedback (e.g., a multi-panel type codebook, a linear combination type codebook, a port selection type codebook) . Although these techniques are described with reference to signals transmitted in one or more directions by a base station 105, a UE 115 may employ similar techniques for transmitting signals multiple times in different directions (e.g., for identifying a beam direction for subsequent transmission or reception by the UE 115) or for transmitting a signal in a single direction (e.g., for transmitting data to a receiving device) .

A receiving device (e.g., a UE 115) may try multiple receive configurations (e.g., directional listening) when receiving various signals from the base station 105, such as synchronization signals, reference signals, beam selection signals, or other control signals. For example, a receiving device may try multiple receive directions by receiving via different antenna subarrays, by processing received signals according to different antenna subarrays, by receiving according to different receive beamforming weight sets (e.g., different directional listening weight sets) applied to signals received at multiple antenna elements of an antenna array, or by processing received signals according to different receive beamforming weight sets applied to signals received at multiple antenna elements of an antenna array, any of which may be referred to as “listening” according to different receive configurations or receive directions. In some examples, a receiving device may use a single receive configuration to receive along a single beam direction (e.g., when receiving a data signal) . The single receive configuration may be aligned in a beam direction determined based on listening according to different receive configuration directions (e.g., a beam direction determined to have a highest signal strength, highest signal-to-noise ratio (SNR) , or otherwise acceptable signal quality based on listening according to multiple beam directions) .

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. Hybrid automatic repeat request (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.

The wireless communications system 100 may include one or more UEs 115 and base stations 105 that may support enhancements to coding systems as described herein. In some examples, a base station 105 may be referred to as a transmitting device and a UE 115 may be referred to as a receiving device. Additionally or alternatively, a UE 115 may be referred to as a transmitting device and a base station 105 may be referred to as a receiving device.

Within wireless communications system 100, a transmitting device (such as a base station 105 or a UE 115) may identify a set of source symbols for a wireless transmission. In some examples, the transmitting device may determine a quantity of the set of source symbols. The transmitting device may then select between a first encoding scheme and a second encoding scheme based on comparing the quantity of source symbols to a threshold quantity (e.g., based on whether the quantity of source symbols in the set is less than the threshold quantity) . In some cases, the first encoding scheme may have a higher overhead than the second encoding scheme, at least for a given failure probability. The first encoding scheme may in some case also use encoding and decoding operations of relatively lower complexity, as compared to the second encoding scheme. For example, the first encoding scheme may be associated with a Raptor code and the second encoding scheme may be associated with a RaptorQ code. The first encoding scheme may be based on a first Galois Field having a size 2 and the second encoding scheme may be based on a second Galois Field having a size 256.

In one example, if the transmitting device determines that the quantity of source symbols in the set is less than the threshold quantity, the transmitting device may select the second encoding scheme (e.g., may select a relatively higher complexity but lower overhead encoding scheme from a set of candidate encoding schemes) to generate the set of encoded symbols. Alternatively, if the transmitting device determines that the quantity of source symbols in the set is greater than or equal to the threshold quantity, the transmitting device may select the first encoding scheme (e.g., may select a relatively lower complexity but higher overhead encoding scheme from a set of candidate encoding schemes) to generate the set of encoded symbols. The transmitting device may then transmit the encoded symbols to a receiving device (such as a UE 115 or a base station 105) . The techniques described herein may enable network nodes to improve efficiency and reliability of decoding transmitted information.

FIG. 2 illustrates an example of a encoding scheme 200 that supports encoding scheme selection for wireless transmissions in accordance with aspects of the present disclosure. In some examples, the encoding scheme 200 may be implemented by aspects of wireless communications system 100. For example, the encoding scheme 200 may be associated with wireless transmissions to or from a device within wireless communications system 100, such as a UE 115 or base station 105.

According to one or more aspects described herein, the encoding scheme 200 may use a Raptor code or a RaptorQ code to encode packets for transmission. A transmitting device (which may alternatively be referred to as a transmitting node or an input node) may encode a set of source symbols 205 (e.g., a quantity K of source symbols 205) into a set of encoded symbols 225. The quantity of encoded symbols 225 may be greater than or equal to the quantity of source symbols 205, and an increased number encoded symbols 255 that are successfully received and decoded at a receiving device (which may alternatively be referred to as a receiving node or an output node) may correspond to an increased probability of the receiving device successfully recovering the set of source symbols 205. In some examples, the encoding scheme 200 may be rateless (e.g., based on a rateless code, such as a fountain code) , and the quantity of encoded symbols 225 may have no upper limit.

The encoding scheme 200 may include a precoding process 210. In the precoding process 210, the input node may map one or more source symbols 205 to each of a set of intermediate symbols 215. The input node may generate a quantity of redundant intermediate symbols 215 (e.g., a quantity of intermediate symbols 215 in addition to a quantity K of intermediate symbols 215 directly mapped to the K source symbols 205) . The intermediate symbols 215 may include a copy of the source symbols 205 as concatenated source symbols. Additionally or alternatively, the redundant intermediate symbols 215 may include a quantity H of half symbols, where each half symbol may include ceil (H/2) source symbols 205, and where ceil (x) may represent a ceiling function mapping x to a least integer that is greater than or equal to x. As depicted herein, Raptor coding uses a Galois field having a size 2 (e.g., finite fields GF (2) ) and RaptorQ coding uses a Galois field having a size 256 (e.g., finite fields GF (256) ) .

The encoding scheme 200 may include an LT coding process 220 following the precoding process 210. In the LT coding process 220, the input node may map the intermediate symbols 215 to the set of encoded symbols 225. The LT coding process 220 may employ a probability mass function of a set of degrees d _i (e.g., d ₁, d ₂, d ₃, etc. ) . In some cases, the degree d _i may represent the quantity of intermediate symbols 215 which the input node may combine into a given encoded symbol 225. For example, if the degree d ₂ is selected for a first encoded symbol 225, two intermediate symbols 215 may be randomly selected and combined into the first encoded symbol 225. In some examples, the intermediate symbols 215 may be combined into encoded symbols 225 using a logic operation such as a logic XOR operation. In some examples, each encoded symbol 225 may include information identifying the source symbols 205 used to construct the encoded symbol 225.

The encoded symbols 225 may be transmitted as a set of one or more encoded packets from the input node to the output node. In some examples, the encoding scheme 200 may be represented by a generator matrix G. The source symbols 205 contained in a set of encoded symbols 225 may be represented by p _j, which may be defined as:

In some examples, one or more sets of encoded symbols 225 may be lost or received with low SNR based on the transmission environment. The output node may receive and successfully decode a subset of the encoded packets (e.g., a quantity N of the encoded packets) via the wireless channel. The source symbols 205 contained in the subset of encoded symbols 225 received by the output node may be represented by d _k, which may be defined by:

Based on the encoding scheme 200, the output node may recover all source symbols 205 in the set of source symbols when the matrix G _nk of the received packets is invertible. Additionally or alternatively, the output node may recover all source symbols 205 in the set of source symbols 205 when the matrix G _nk of the received packets has a rank K, where K is the quantity of source symbols 205 in the set of source symbols.

The output node may decode the N received encoded symbols 225 to obtain the source symbols 205. The output node may begin a decoding process by identifying an encoded symbol 225 with an index t _j that is connected to a single source symbol 205 with an index s _i. The output node may determine the encoded symbol 225 with index t _j is equivalent to the source symbol 205 with index s _i. In some cases, the output node may then apply an XOR operation to each other encoded symbol 225 connected to the source symbol 205 with index s _i, and remove all edges connected to the source symbol 205 with index s _i. The output node may repeat this process until each source symbol 205 is determined from the received encoded symbols 225.

In some cases, Raptor codes and RaptorQ codes may be examples of rateless code, where a set of source symbols (e.g., K symbols) may be encoded as any quantity of encoded symbols (e.g., a quantity of symbols greater than or equal to K symbols) . Encoding the source symbols may include combining one or more source symbols into each encoded symbol. In one example, a RaptorQ code may have reduced overhead but increased encoding and decoding complexity relative to a Raptor code. For example, the Raptor code may be associated with a Galois Field size of 2, and the RaptorQ code may be associated with a Galois Field size of 256. A failure probability of the Raptor code may be defined as

and a failure probability of the RaptorQ code may be defined as

Although the RaptorQ code has a lower failure probability, the RaptorQ code may have a larger complexity as RaptorQ code uses a Galois field having a larger (e.g., GF (256) compared to GF (2) ) . In some cases, the RaptorQ code may provide lower overhead relative to the Raptor code, at least for a given failure probability (e.g., for a failure probability of 10 ^-5, the Raptor code may have an overhead of 16 symbols (N-K = 16) , and the RaptorQ code may have an overhead of one symbol (N-K = 1) .

Depending on the quantity K of source symbols, the overhead associated with a given encoding scheme (e.g., a code used as part of the encoding scheme) may be relatively more or relatively less substantial (e.g., a relatively larger or smaller portion of the quantity N of encoded symbols 225 that must be successfully received and decoded by the output node in order to recover the set of source symbols 205. For example where K is 20, an overhead of 16 symbols may be relatively large, and where K is 2048, an overhead of 16 symbols may be relatively small. According to methods described herein, a transmitting device (e.g., a base station 105 or a UE 115) may be configured to select an encoding scheme (from a set of candidate encoding schemes) based on a quantity of source symbols for a wireless transmission-that is, based on K. In some cases, the wireless transmission may be associated with one or more multimedia broadcast multicast service (MBMS) applications. Additionally or alternatively, the wireless transmission may be associated with satellite communications, internet protocol television (IPTV) , or digital video or audio broadcasting. In some examples, the transmitting device may encode a set of source symbols using a relatively more complex but lower overhead encoding scheme (e.g., based on a RaptorQ code, which may be referred to as a RaptorQ encoding scheme) if the quantity of source symbols is less than a threshold, and the transmitting device may encode the set of source symbols using a relatively less complex but higher overhead encoding scheme (e.g., based on a RaptorQ code, which may be referred to as a Raptor encoding scheme) if the quantity of source symbols is greater than or equal to the threshold. Thus, techniques described herein may improve network and device efficiencies based on selecting an encoding scheme (e.g., a code for encoding and decoding) based on one or more performance tradeoffs, such as between complexity and overhead.

FIG. 3 illustrates an example of a process flow 300 that supports encoding scheme selection for wireless transmissions in accordance with aspects of the present disclosure. In some examples, the process flow 300 may be implemented by aspects of wireless communications system 100.

Process flow 300 may include a transmitting device 105-a (such as a base station 105 or a UE 115) and a receiving device 115-a (such as a base station 105 or a UE 115) . In this example, the transmitting device 105-a may act as an input node and perform encoding, while the receiving device 115-a may act as an output node and perform decoding. In one example, a base station 105 may act as the input node and a UE 115 may act as the output node. In another example, a UE 115 may act as the input node while a base station 105 may act as the output node. In other examples, the communications may be between two UEs 115 or two base stations 105, or between any other quantity of nodes of the same or different types. The transmitting device 105-a may use a selected encoding scheme and the receiving device 115 may use a corresponding decoding scheme.

At 305, the transmitting device 105-a may identify a set of source symbols for a wireless transmission. As just one example, the wireless transmission may be associated with one or more MBMS applications, satellite communications, IPTV, or digital video or audio broadcasting. The wireless transmission may include data transmission. The data transmission may be encoded to reduce packet loss, for security, or the like. The source symbols may be included in one or more data packets for transmission.

At 310, the transmitting device 105-a may select an encoding scheme based on a quantity (K) of source symbols in the set identified at 305. For example, the transmitting device 105-a may select between a first encoding scheme and a second encoding scheme (or alternatively between any number of candidate encoding schemes in a set of candidate encoding schemes) . In one example, the transmitting device 105-a may select the encoding scheme based on comparing a quantity of source symbols in the set to a threshold quantity (e.g., based on whether the quantity of source symbols in the set is less than the threshold quantity) .

In some examples, a first encoding scheme in a set of candidate encoding schemes may have a higher overhead than a second encoding scheme in the set of candidate encoding schemes, at least for a same (e.g., target, specified) failure probability. In some examples, the first encoding scheme may be associated with a first rateless code and the second encoding scheme may be associated with a second rateless code. For instance, the first encoding scheme may be associated with (e.g., use) a Raptor code and the second encoding scheme may be associated with (e.g., use) a RaptorQ code. Additionally or alternatively, the first encoding scheme may be based on a first Galois Field and the second encoding scheme may be based on a second Galois Field. The size of the second Galois Field may be greater than a size of the first Galois Field. For example, the size of the first Galois Field may be 2 and the size of the second Galois Field may be 256. In one example, to achieve the same failure probability, the RaptorQ code may have a lower overhead than the Raptor code.

In one example, the transmitting device 105-a may determine that the quantity of source symbols in the set is less than the threshold quantity. The transmitting device 105-amay then select a relatively higher complexity but lower overhead encoding scheme (e.g., the second encoding scheme) to generate the set of encoded symbols. Additionally or alternatively, the transmitting device 105-a may determine that the quantity of source symbols in the set is greater than the threshold quantity, and may then select a relatively higher overhead but lower complexity encoding scheme (e.g., the first encoding scheme) to generate the set of encoded symbols.

At 315, the transmitting device 105-a may generate a set of encoded symbols based on the selected encoding scheme. For example, the transmitting device 105-a may generate the set of encoded symbols based on a code associated with the selected encoding scheme. In some instances, the transmitting device 105-a may encode the intermediate symbols using the selected encoding scheme to create a set of encoded symbols. In some cases, the set of encoded symbols may be generated at an application layer of a protocol stack for the transmitting device 105-a.

At 320, the transmitting device 105-a may transmit the set of encoded symbols to the receiving device 115-a. The set of encoded symbols may be broadcast or unicast. A receiver at the receiving device 115-a may receive the set of encoded symbols. In some cases, at 325, the transmitting device 105-a may indicate the operative encoding scheme to the receiving device 115-a.

At 330, the receiving device 115-a may identify the encoding scheme based on receiving the indication from the transmitting device 105-a. The receiving device 115-a may use a corresponding decoding scheme to decode the encoded symbols. For example, the decoding process performed by the receiving device 115-a may be complementary to the encoding process performed by the transmitting device 105-a.

At 335, the receiving device 115-a may generate a set of source symbols based on the decoding scheme that corresponds to the encoding scheme. In one example, the receiving device 115-a may generate intermediate symbols from the encoded symbols. The receiving device 115-a may generate a set of intermediate symbols from the set of encoded symbols using either the first encoding scheme or the second encoding scheme.

At 340, the receiving device 115-a may process the decoded source symbols, which may include using the source symbols in an application, outputting at least a portion of the source symbols, transmitting the source symbols, or any other type of data processing or signaling.

FIG. 4 shows a block diagram 400 of a device 405 that supports encoding scheme selection for wireless transmissions in accordance with aspects of the present disclosure. The device 405 may be an example of aspects of a UE 115 or base station 105 as described herein. The device 405 may include a receiver 410, a communications manager 415, and a transmitter 420. The device 405 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses) .

Receiver 410 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 encoding scheme selection for wireless transmissions, etc. ) . Information may be passed on to other components of the device 405. The receiver 410 may be an example of aspects of the

transceiver

720 or 820 as described with reference to FIGs. 7 and 8. The receiver 410 may utilize a single antenna or a set of antennas.

The communications manager 415 may identify a set of source symbols for a wireless transmission, select between a first encoding scheme and a second encoding scheme based on whether a quantity of source symbols in the set is less than a threshold quantity, where the first encoding scheme has a higher overhead than the second encoding scheme, generate a set of encoded symbols based on the selected encoding scheme, and transmit the set of encoded symbols. The communications manager 415 may be an example of aspects of the

communications manager

710 or 810 as described herein.

The communications manager 415, 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 415, 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 415, 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 415, 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 415, 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.

Transmitter 420 may transmit signals generated by other components of the device 405. In some examples, the transmitter 420 may be collocated with a receiver 410 in a transceiver module. For example, the transmitter 420 may be an example of aspects of the

transceiver

720 or 820 as described with reference to FIGs. 7 and 8. The transmitter 420 may utilize a single antenna or a set of antennas.

FIG. 5 shows a block diagram 500 of a device 505 that supports encoding scheme selection for wireless transmissions in accordance with aspects of the present disclosure. The device 505 may be an example of aspects of a device 405, 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 540. 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) .

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 encoding scheme selection for wireless transmissions, 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

720 or 820 as described with reference to FIGs. 7 and 8. The receiver 510 may utilize a single antenna or a set of antennas.

The communications manager 515 may be an example of aspects of the communications manager 415 as described herein. The communications manager 515 may include a symbol identification component 520, a selection component 525, an encoding component 530, and a transmission component 535. The communications manager 515 may be an example of aspects of the

communications manager

710 or 810 as described herein.

The symbol identification component 520 may identify a set of source symbols for a wireless transmission. The selection component 525 may select between a first encoding scheme and a second encoding scheme based on whether a quantity of source symbols in the set is less than a threshold quantity, where the first encoding scheme has a higher overhead than the second encoding scheme. The encoding component 530 may generate a set of encoded symbols based on the selected encoding scheme. The transmission component 535 may transmit the set of encoded symbols.

Transmitter 540 may transmit signals generated by other components of the device 505. In some examples, the transmitter 540 may be collocated with a receiver 510 in a transceiver module. For example, the transmitter 540 may be an example of aspects of the

transceiver

720 or 820 as described with reference to FIGs. 7 and 8. The transmitter 540 may utilize a single antenna or a set of antennas.

FIG. 6 shows a block diagram 600 of a communications manager 605 that supports encoding scheme selection for wireless transmissions in accordance with aspects of the present disclosure. The communications manager 605 may be an example of aspects of a communications manager 415, a communications manager 515, or a communications manager 710 described herein. The communications manager 605 may include a symbol identification component 610, a selection component 615, an encoding component 620, a transmission component 625, a quantity determination component 630, and an indication component 635. Each of these modules may communicate, directly or indirectly, with one another (e.g., via one or more buses) .

The symbol identification component 610 may identify a set of source symbols for a wireless transmission. In some cases, the wireless transmission is associated with one or more MBMS applications. The selection component 615 may select between a first encoding scheme and a second encoding scheme based on whether a quantity of source symbols in the set is less than a threshold quantity, where the first encoding scheme has a higher overhead than the second encoding scheme.

The indication component 635 may transmit, to a receiver, an indication of the selected encoding scheme. In some cases, the first encoding scheme is associated with a first rateless code and the second encoding scheme is associated with a second rateless code. In some cases, the first encoding scheme and the second encoding scheme are configured to have a same failure probability, and where the first encoding scheme has the higher overhead than the second encoding scheme when the second encoding scheme are configured to have the same failure probability.

In some cases, the first encoding scheme is associated with a Raptor code and the second encoding scheme is associated with a RaptorQ code. In some cases, the first encoding scheme is based on a first Galois Field and the second encoding scheme is based on a second Galois Field, a size of the second Galois Field being greater than a size of the first Galois Field. In some cases, the size of the first Galois Field is 2 and the size of the second Galois Field is 256.

The encoding component 620 may generate a set of encoded symbols based on the selected encoding scheme. In some cases, the set of encoded symbols may be generated at an application layer of a protocol stack for the device. The transmission component 625 may transmit the set of encoded symbols.

The quantity determination component 630 may determine that the quantity of source symbols in the set is less than the threshold quantity. In some examples, the selection component 615 may select the second encoding scheme to generate the set of encoded symbols.

In some examples, the quantity determination component 630 may determine that the quantity of source symbols in the set is greater than the threshold quantity. In some examples, the selection component 615 may select the first encoding scheme to generate the set of encoded symbols.

FIG. 7 shows a diagram of a system 700 including a device 705 that supports encoding scheme selection for wireless transmissions in accordance with aspects of the present disclosure. The device 705 may be an example of or include the components of device 405, device 505, or a UE 115 as described herein. The device 705 may include components for bi-directional voice and data communications including components for transmitting and receiving communications, including a communications manager 710, a transceiver 720, an antenna 725, memory 730, a processor 740, and an I/O controller 750. These components may be in electronic communication via one or more buses (e.g., bus 755) .

The communications manager 710 may identify a set of source symbols for a wireless transmission, select between a first encoding scheme and a second encoding scheme based on whether a quantity of source symbols in the set is less than a threshold quantity, where the first encoding scheme has a higher overhead than the second encoding scheme, generate a set of encoded symbols based on the selected encoding scheme, and transmit the set of encoded symbols.

Transceiver 720 may communicate bi-directionally, via one or more antennas, wired, or wireless links as described above. For example, the transceiver 720 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. The transceiver 720 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 725. However, in some cases the device may have more than one antenna 725, which may be capable of concurrently transmitting or receiving multiple wireless transmissions.

The memory 730 may include RAM, ROM, or a combination thereof. The memory 730 may store computer-readable code 735 including instructions that, when executed by a processor (e.g., the processor 740) cause the device to perform various functions described herein. In some cases, the memory 730 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 740 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 740 may be configured to operate a memory array using a memory controller. In other cases, a memory controller may be integrated into the processor 740. The processor 740 may be configured to execute computer-readable instructions stored in a memory (e.g., the memory 730) to cause the device 705 to perform various functions (e.g., functions or tasks supporting encoding scheme selection for wireless transmissions) .

The I/O controller 750 may manage input and output signals for the device 705. The I/O controller 750 may also manage peripherals not integrated into the device 705. In some cases, the I/O controller 750 may represent a physical connection or port to an external peripheral. In some cases, the I/O controller 750 may utilize an operating system such as

or another known operating system. In other cases, the I/O controller 750 may represent or interact with a modem, a keyboard, a mouse, a touchscreen, or a similar device. In some cases, the I/O controller 750 may be implemented as part of a processor. In some cases, a user may interact with the device 705 via the I/O controller 750 or via hardware components controlled by the I/O controller 750.

The code 735 may include instructions to implement aspects of the present disclosure, including instructions to support wireless communications. The code 735 may be stored in a non-transitory computer-readable medium such as system memory or other type of memory (e.g., memory 730 with reference to FIG. 7 and/or memory 830 with reference to FIG. 8) . In some cases, the code 735 may not be directly executable by the processor 740 but may cause a computer (e.g., when compiled and executed) to perform functions described herein.

FIG. 8 shows a diagram of a system 800 including a device 805 that supports encoding scheme selection for wireless transmissions in accordance with aspects of the present disclosure. The device 805 may be an example of or include the components of device 405, device 505, 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, a network communications manager 815, a transceiver 820, an antenna 825, memory 830, a processor 840, and an inter-station communications manager 845. These components may be in electronic communication via one or more buses (e.g., bus 855) .

The communications manager 810 may identify a set of source symbols for a wireless transmission, select between a first encoding scheme and a second encoding scheme based on whether a quantity of source symbols in the set is less than a threshold quantity, where the first encoding scheme has a higher overhead than the second encoding scheme, generate a set of encoded symbols based on the selected encoding scheme, and transmit the set of encoded symbols.

Network communications manager 815 may manage communications with the core network (e.g., via one or more wired backhaul links) . For example, the network communications manager 815 may manage the transfer of data communications for client devices, such as one or more UEs 115.

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 RAM, ROM, or a combination thereof. The memory 830 may store computer-readable code 835 including instructions that, when executed by a processor (e.g., the processor 840) cause the device to perform various functions described herein. In some cases, the memory 830 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 840 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 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 encoding scheme selection for wireless transmissions) .

Inter-station communications manager 845 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 845 may coordinate scheduling for transmissions to UEs 115 for various interference mitigation techniques such as beamforming or joint transmission. In some examples, inter-station communications manager 845 may provide an X2 interface within an LTE/LTE-Awireless communication network technology to provide communication between base stations 105.

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 flowchart illustrating a method 900 that supports encoding scheme selection for wireless transmissions in accordance with aspects of the present disclosure. The operations of method 900 may be implemented by a UE 115 or base station 105 or its components as described herein. For example, the operations of method 900 may be performed by a communications manager as described with reference to FIGs. 4 through 8.In some examples, a UE or base station may execute a set of instructions to control the functional elements of the UE or base station to perform the functions described below. Additionally or alternatively, a UE or base station may perform aspects of the functions described below using special-purpose hardware.

At 905, the UE or base station may identify a set of source symbols for a wireless transmission. The operations of 905 may be performed according to the methods described herein. In some examples, aspects of the operations of 905 may be performed by a symbol identification component as described with reference to FIGs. 4 through 8. Additionally or alternatively, means for performing 905 may, but not necessarily, include, for example, I/O controller 750, antenna 725, transceiver 720, communications manager 710, memory 730 (including code 735) , processor 740 and/or bus 745. Additionally or alternatively, means for performing 905 may, but not necessarily, include, for example, communications manager 810, network communications manager 815, transceiver 820, antenna 825, memory 830 (including code 835) , processor 840, inter-station communications manager 845, and/or bus 855.

At 910, the UE or base station may select between a first encoding scheme and a second encoding scheme based on whether a quantity of source symbols in the set is less than a threshold quantity, where the first encoding scheme has a higher overhead than the second encoding scheme. The operations of 910 may be performed according to the methods described herein. In some examples, aspects of the operations of 910 may be performed by a selection component as described with reference to FIGs. 4 through 8. Additionally or alternatively, means for performing 910 may, but not necessarily, include, for example, I/O controller 750, antenna 725, transceiver 720, communications manager 710, memory 730 (including code 735) , processor 740 and/or bus 745. Additionally or alternatively, means for performing 910 may, but not necessarily, include, for example, communications manager 810, network communications manager 815, transceiver 820, antenna 825, memory 830 (including code 835) , processor 840, inter-station communications manager 845, and/or bus 855.

At 915, the UE or base station may generate a set of encoded symbols based on the selected encoding scheme. The operations of 915 may be performed according to the methods described herein. In some examples, aspects of the operations of 915 may be performed by an encoding component as described with reference to FIGs. 4 through 8. Additionally or alternatively, means for performing 915 may, but not necessarily, include, for example, I/O controller 750, antenna 725, transceiver 720, communications manager 710, memory 730 (including code 735) , processor 740 and/or bus 745. Additionally or alternatively, means for performing 915 may, but not necessarily, include, for example, communications manager 810, network communications manager 815, transceiver 820, antenna 825, memory 830 (including code 835) , processor 840, inter-station communications manager 845, and/or bus 855.

At 920, the UE or base station may transmit the set of encoded symbols. The operations of 920 may be performed according to the methods described herein. In some examples, aspects of the operations of 920 may be performed by a transmission component as described with reference to FIGs. 4 through 8. Additionally or alternatively, means for performing 920 may, but not necessarily, include, for example, I/O controller 750, antenna 725, transceiver 720, communications manager 710, memory 730 (including code 735) , processor 740 and/or bus 745. Additionally or alternatively, means for performing 920 may, but not necessarily, include, for example, communications manager 810, network communications manager 815, transceiver 820, antenna 825, memory 830 (including code 835) , processor 840, inter-station communications manager 845, and/or bus 855.

FIG. 10 shows a flowchart illustrating a method 1000 that supports encoding scheme selection for wireless transmissions in accordance with aspects of the present disclosure. The operations of method 1000 may be implemented by a UE 115 or base station 105 or its components as described herein. For example, the operations of method 1000 may be performed by a communications manager as described with reference to FIGs. 4 through 8. In some examples, a UE or base station may execute a set of instructions to control the functional elements of the UE or base station to perform the functions described below. Additionally or alternatively, a UE or base station may perform aspects of the functions described below using special-purpose hardware.

At 1005, the UE or base station may identify a set of source symbols for a wireless transmission. The operations of 1005 may be performed according to the methods described herein. In some examples, aspects of the operations of 1005 may be performed by a symbol identification component as described with reference to FIGs. 4 through 8. Additionally or alternatively, means for performing 1005 may, but not necessarily, include, for example, I/O controller 750, antenna 725, transceiver 720, communications manager 710, memory 730 (including code 735) , processor 740 and/or bus 745. Additionally or alternatively, means for performing 1005 may, but not necessarily, include, for example, communications manager 810, network communications manager 815, transceiver 820, antenna 825, memory 830 (including code 835) , processor 840, inter-station communications manager 845, and/or bus 855.

At 1010, the UE or base station may determine that the quantity of source symbols in the set is less than the threshold quantity. The operations of 1010 may be performed according to the methods described herein. In some examples, aspects of the operations of 1010 may be performed by a quantity determination component as described with reference to FIGs. 4 through 8. Additionally or alternatively, means for performing 1010 may, but not necessarily, include, for example, I/O controller 750, antenna 725, transceiver 720, communications manager 710, memory 730 (including code 735) , processor 740 and/or bus 745. Additionally or alternatively, means for performing 1010 may, but not necessarily, include, for example, communications manager 810, network communications manager 815, transceiver 820, antenna 825, memory 830 (including code 835) , processor 840, inter-station communications manager 845, and/or bus 855.

At 1015, the UE or base station may select a second encoding scheme between a first encoding scheme and the second encoding scheme to generate the set of encoded symbols. The operations of 1015 may be performed according to the methods described herein. In some examples, aspects of the operations of 1015 may be performed by a selection component as described with reference to FIGs. 4 through 8. Additionally or alternatively, means for performing 1015 may, but not necessarily, include, for example, I/O controller 750, antenna 725, transceiver 720, communications manager 710, memory 730 (including code 735) , processor 740 and/or bus 745. Additionally or alternatively, means for performing 1015 may, but not necessarily, include, for example, communications manager 810, network communications manager 815, transceiver 820, antenna 825, memory 830 (including code 835) , processor 840, inter-station communications manager 845, and/or bus 855.

At 1020, the UE or base station may generate a set of encoded symbols based on the selected encoding scheme. The operations of 1020 may be performed according to the methods described herein. In some examples, aspects of the operations of 1020 may be performed by an encoding component as described with reference to FIGs. 4 through 8. Additionally or alternatively, means for performing 1020 may, but not necessarily, include, for example, I/O controller 750, antenna 725, transceiver 720, communications manager 710, memory 730 (including code 735) , processor 740 and/or bus 745. Additionally or alternatively, means for performing 1020 may, but not necessarily, include, for example, communications manager 810, network communications manager 815, transceiver 820, antenna 825, memory 830 (including code 835) , processor 840, inter-station communications manager 845, and/or bus 855.

At 1025, the UE or base station may transmit the set of encoded symbols. The operations of 1025 may be performed according to the methods described herein. In some examples, aspects of the operations of 1025 may be performed by a transmission component as described with reference to FIGs. 4 through 8. Additionally or alternatively, means for performing 1025 may, but not necessarily, include, for example, I/O controller 750, antenna 725, transceiver 720, communications manager 710, memory 730 (including code 735) , processor 740 and/or bus 745. Additionally or alternatively, means for performing 1025 may, but not necessarily, include, for example, communications manager 810, network communications manager 815, transceiver 820, antenna 825, memory 830 (including code 835) , processor 840, inter-station communications manager 845, and/or bus 855.

FIG. 11 shows a flowchart illustrating a method 1100 that supports encoding scheme selection for wireless transmissions in accordance with aspects of the present disclosure. The operations of method 1100 may be implemented by a UE 115 or base station 105 or its components as described herein. For example, the operations of method 1100 may be performed by a communications manager as described with reference to FIGs. 4 through 8.In some examples, a UE or base station may execute a set of instructions to control the functional elements of the UE or base station to perform the functions described below. Additionally or alternatively, a UE or base station may perform aspects of the functions described below using special-purpose hardware.

At 1105, the UE or base station may identify a set of source symbols for a wireless transmission. The operations of 1105 may be performed according to the methods described herein. In some examples, aspects of the operations of 1105 may be performed by a symbol identification component as described with reference to FIGs. 4 through 8. Additionally or alternatively, means for performing 1105 may, but not necessarily, include, for example, I/O controller 750, antenna 725, transceiver 720, communications manager 710, memory 730 (including code 735) , processor 740 and/or bus 745. Additionally or alternatively, means for performing 1105 may, but not necessarily, include, for example, communications manager 810, network communications manager 815, transceiver 820, antenna 825, memory 830 (including code 835) , processor 840, inter-station communications manager 845, and/or bus 855.

At 1110, the UE or base station may determine that the quantity of source symbols in the set is greater than the threshold quantity. The operations of 1110 may be performed according to the methods described herein. In some examples, aspects of the operations of 1110 may be performed by a quantity determination component as described with reference to FIGs. 4 through 8. Additionally or alternatively, means for performing 1110 may, but not necessarily, include, for example, I/O controller 750, antenna 725, transceiver 720, communications manager 710, memory 730 (including code 735) , processor 740 and/or bus 745. Additionally or alternatively, means for performing 1110 may, but not necessarily, include, for example, communications manager 810, network communications manager 815, transceiver 820, antenna 825, memory 830 (including code 835) , processor 840, inter-station communications manager 845, and/or bus 855.

At 1115, the UE or base station may select a first encoding scheme between the first encoding scheme and a second encoding scheme to generate the set of encoded symbols. The operations of 1115 may be performed according to the methods described herein. In some examples, aspects of the operations of 1115 may be performed by a selection component as described with reference to FIGs. 4 through 8. Additionally or alternatively, means for performing 1115 may, but not necessarily, include, for example, I/O controller 750, antenna 725, transceiver 720, communications manager 710, memory 730 (including code 735) , processor 740 and/or bus 745. Additionally or alternatively, means for performing 1115 may, but not necessarily, include, for example, communications manager 810, network communications manager 815, transceiver 820, antenna 825, memory 830 (including code 835) , processor 840, inter-station communications manager 845, and/or bus 855.

At 1120, the UE or base station may generate a set of encoded symbols based on the selected encoding scheme. The operations of 1120 may be performed according to the methods described herein. In some examples, aspects of the operations of 1120 may be performed by an encoding component as described with reference to FIGs. 4 through 8. Additionally or alternatively, means for performing 1120 may, but not necessarily, include, for example, I/O controller 750, antenna 725, transceiver 720, communications manager 710, memory 730 (including code 735) , processor 740 and/or bus 745. Additionally or alternatively, means for performing 1120 may, but not necessarily, include, for example, communications manager 810, network communications manager 815, transceiver 820, antenna 825, memory 830 (including code 835) , processor 840, inter-station communications manager 845, and/or bus 855.

At 1125, the UE or base station may transmit the set of encoded symbols. The operations of 1125 may be performed according to the methods described herein. In some examples, aspects of the operations of 1125 may be performed by a transmission component as described with reference to FIGs. 4 through 8. Additionally or alternatively, means for performing 1125 may, but not necessarily, include, for example, I/O controller 750, antenna 725, transceiver 720, communications manager 710, memory 730 (including code 735) , processor 740 and/or bus 745. Additionally or alternatively, means for performing 1125 may, but not necessarily, include, for example, communications manager 810, network communications manager 815, transceiver 820, antenna 825, memory 830 (including code 835) , processor 840, inter-station communications manager 845, and/or bus 855.

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.

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 random-access memory (RAM) , read-only memory (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 communication, comprising:

identifying a set of source symbols for a wireless transmission;

selecting between a first encoding scheme and a second encoding scheme based at least in part on whether a quantity of source symbols in the set is less than a threshold quantity, wherein the first encoding scheme has a higher overhead than the second encoding scheme;

generating a set of encoded symbols based at least in part on the selected encoding scheme; and

transmitting the set of encoded symbols.
The method of claim 1, wherein selecting between the first encoding scheme and the second encoding scheme comprises:

determining that the quantity of source symbols in the set is less than the threshold quantity; and

selecting the second encoding scheme to generate the set of encoded symbols.
The method of claim 1, wherein selecting between the first encoding scheme and the second encoding scheme comprises:

determining that the quantity of source symbols in the set is greater than the threshold quantity; and

selecting the first encoding scheme to generate the set of encoded symbols.
The method of claim 1, further comprising:

transmitting, to a receiver, an indication of the selected encoding scheme.
The method of claim 1, wherein the first encoding scheme is associated with a rapid tornado (Raptor) code and the second encoding scheme is associated with a RaptorQ code.
The method of claim 1, wherein the first encoding scheme is based at least in part on a first Galois Field and the second encoding scheme is based at least in part on a second Galois Field, a size of the second Galois Field being greater than a size of the first Galois Field.
The method of claim 6, wherein the size of the first Galois Field is 2 and the size of the second Galois Field is 256.
The method of claim 1, wherein the first encoding scheme is associated with a first rateless code and the second encoding scheme is associated with a second rateless code.
The method of claim 1, wherein the first encoding scheme and the second encoding scheme are configured to have a same failure probability, and wherein the first encoding scheme has the higher overhead than the second encoding scheme when the second encoding scheme are configured to have the same failure probability.
The method of claim 1, wherein the wireless transmission is associated with one or more multimedia broadcast multicast service (MBMS) applications.
The method of claim 10, wherein the method is performed by a device, and wherein the set of encoded symbols is generated at an application layer of a protocol stack for the device.
An apparatus for wireless communication, comprising:

a processor of a transmitting device,

memory in electronic communication with the processor, the memory and the processor configured to cause the apparatus to:

identify a set of source symbols for a wireless transmission;

select between a first encoding scheme and a second encoding scheme based at least in part on whether a quantity of source symbols in the set is less than a threshold quantity, wherein the first encoding scheme has a higher overhead than the second encoding scheme;

generate a set of encoded symbols based at least in part on the selected encoding scheme; and

transmit the set of encoded symbols.
The apparatus of claim 12, the memory and the processor further configured to cause the apparatus to:

determine that the quantity of source symbols in the set is less than the threshold quantity; and

select the second encoding scheme to generate the set of encoded symbols.
The apparatus of claim 12, the memory and the processor further configured to cause the apparatus to:

determine that the quantity of source symbols in the set is greater than the threshold quantity; and

select the first encoding scheme to generate the set of encoded symbols.
The apparatus of claim 12, the memory and the processor further configured to cause the apparatus to:

transmit, to a receiver, an indication of the selected encoding scheme.
The apparatus of claim 12, wherein the first encoding scheme is associated with a rapid tornado (Raptor) code and the second encoding scheme is associated with a RaptorQ code.
The apparatus of claim 12, wherein the first encoding scheme is based at least in part on a first Galois Field and the second encoding scheme is based at least in part on a second Galois Field, a size of the second Galois Field being greater than a size of the first Galois Field.
The apparatus of claim 17, wherein the size of the first Galois Field is 2 and the size of the second Galois Field is 256.
The apparatus of claim 12, wherein the first encoding scheme is associated with a first rateless code and the second encoding scheme is associated with a second rateless code.
The apparatus of claim 12, wherein the first encoding scheme and the second encoding scheme are configured to have a same failure probability, and wherein the first encoding scheme has the higher overhead than the second encoding scheme when the second encoding scheme are configured to have the same failure probability.
The apparatus of claim 12, wherein the wireless transmission is associated with one or more multimedia broadcast multicast service (MBMS) applications.
The apparatus of claim 21, wherein the memory and processor are configured to cause the apparatus to generate the set of encoded symbols at an application layer of a protocol stack for the apparatus.
An apparatus for wireless communication, comprising:

means for identifying a set of source symbols for a wireless transmission;

means for selecting between a first encoding scheme and a second encoding scheme based at least in part on whether a quantity of source symbols in the set is less than a threshold quantity, wherein the first encoding scheme has a higher overhead than the second encoding scheme;

means for generating a set of encoded symbols based at least in part on the selected encoding scheme; and

means for transmitting the set of encoded symbols.
The apparatus of claim 23, wherein the means for selecting between the first encoding scheme and the second encoding scheme comprises:

means for determining that the quantity of source symbols in the set is less than the threshold quantity; and

means for selecting the second encoding scheme to generate the set of encoded symbols.
The apparatus of claim 23, wherein the means for selecting between the first encoding scheme and the second encoding scheme comprises:

means for determining that the quantity of source symbols in the set is greater than the threshold quantity; and

means for selecting the first encoding scheme to generate the set of encoded symbols.
The apparatus of claim 23, further comprising:

means for transmitting, to a receiver, an indication of the selected encoding scheme.
The apparatus of claim 23, wherein the first encoding scheme is associated with a rapid tornado (Raptor) code and the second encoding scheme is associated with a RaptorQ code.
The apparatus of claim 23, wherein the first encoding scheme is based at least in part on a first Galois Field and the second encoding scheme is based at least in part on a second Galois Field, a size of the second Galois Field being greater than a size of the first Galois Field.
The apparatus of claim 28, wherein the size of the first Galois Field is 2 and the size of the second Galois Field is 256.
The apparatus of claim 23, wherein the first encoding scheme is associated with a first rateless code and the second encoding scheme is associated with a second rateless code.
The apparatus of claim 23, wherein the first encoding scheme and the second encoding scheme are configured to have a same failure probability, and wherein the first encoding scheme has the higher overhead than the second encoding scheme when the second encoding scheme are configured to have the same failure probability.
The apparatus of claim 23, wherein the wireless transmission is associated with one or more multimedia broadcast multicast service (MBMS) applications.
The apparatus of claim 32, wherein the means for generating the set of encoded symbols comprise means for generating the set of encoded symbols at an application layer of a protocol stack for the apparatus.
A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by a processor to:

identify a set of source symbols for a wireless transmission;

select between a first encoding scheme and a second encoding scheme based at least in part on whether a quantity of source symbols in the set is less than a threshold quantity, wherein the first encoding scheme has a higher overhead than the second encoding scheme;

generate a set of encoded symbols based at least in part on the selected encoding scheme; and

transmit the set of encoded symbols.
The non-transitory computer-readable medium of claim 34, wherein the instructions to select between the first encoding scheme and the second encoding scheme are executable to:

determine that the quantity of source symbols in the set is less than the threshold quantity; and

select the second encoding scheme to generate the set of encoded symbols.
The non-transitory computer-readable medium of claim 34, wherein the instructions to select between the first encoding scheme and the second encoding scheme are executable to:

determine that the quantity of source symbols in the set is greater than the threshold quantity; and

select the first encoding scheme to generate the set of encoded symbols.
The non-transitory computer-readable medium of claim 34, wherein the instructions are further executable to:

transmit, to a receiver, an indication of the selected encoding scheme.
The non-transitory computer-readable medium of claim 34, wherein the first encoding scheme is associated with a rapid tornado (Raptor) code and the second encoding scheme is associated with a RaptorQ code.
The non-transitory computer-readable medium of claim 34, wherein the first encoding scheme is based at least in part on a first Galois Field and the second encoding scheme is based at least in part on a second Galois Field, a size of the second Galois Field being greater than a size of the first Galois Field.
The non-transitory computer-readable medium of claim 39, wherein the size of the first Galois Field is 2 and the size of the second Galois Field is 256.
The non-transitory computer-readable medium of claim 34, wherein the first encoding scheme is associated with a first rateless code and the second encoding scheme is associated with a second rateless code.
The non-transitory computer-readable medium of claim 34, wherein the first encoding scheme and the second encoding scheme are configured to have a same failure probability, and wherein the first encoding scheme has the higher overhead than the second encoding scheme when the second encoding scheme are configured to have the same failure probability.
The non-transitory computer-readable medium of claim 34, wherein the wireless transmission is associated with one or more multimedia broadcast multicast service (MBMS) applications.
The non-transitory computer-readable medium of claim 43, wherein the instructions executable by the processor to generate the set of encoded symbols are executable by the processor to generate the encoded symbols at an application layer of a device that includes the processor.