US20200322941A1 - Multiple tri-state harq processes - Google Patents

Abstract

Methods, systems, and devices are described for wireless communication. A transmitting device may send a signal including multiple transport blocks corresponding to multiple simultaneous hybrid automatic repeat request (HARQ) processes. Additional control information may be used to support the multiple simultaneous HARQ processes. For instance, the additional control information may indicate the number of available HARQ processes, an activity state for each HARQ process (e.g., active new data, active retransmission, or inactive), and the redundancy versions of each HARQ process. In some cases, the additional control information may be included in a downlink grant. A receiving device may respond with an acknowledgement or negative acknowledgment (ACK/NACK) for each of the transport blocks. The transmitting device may identify a retransmission status for each HARQ process based on the ACK/NACKs, and transmit new redundancy versions (or new data) to the receiving device.

Description

CROSS REFERENCES
• The present application for patent is a Continuation of U.S. patent application Ser. No. 15/012,541 by Mallik et al., entitled “Multiple Tri-State HARQ Processes” filed Feb. 1, 2016, which claims priority to U.S. Provisional Patent Application No. 62/114,974 by Mallik et al., entitled “Multiple Tri-State HARQ Processes,” filed Feb. 11, 2015, assigned to the assignee hereof, and expressly incorporated by reference herein.
BACKGROUND
• The following relates generally to wireless communication, and more specifically to multiple tri-state hybrid automatic repeat request (HARQ) processes.
• 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 multiple-access systems 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 code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, and orthogonal frequency division multiple access (OFDMA) systems, (e.g., a Long Term Evolution (LTE) system).
• By way of example, a wireless multiple-access communications system may include a number of base stations, each simultaneously supporting communication for multiple communication devices, which may be otherwise known as user equipment (UEs). A base station may communicate with the communication devices on downlink channels (e.g., for transmissions from a base station to a UE) and uplink channels (e.g., for transmissions from a UE to a base station).
• Wireless devices may utilize a hybrid automatic repeat request (HARQ) scheme to increase the reliability of a communication link. Accordingly, a transmitting device may send a transport block to a receiving device, which may respond with an acknowledgement (ACK) or a negative ACK (NACK) (i.e., an ACK/NACK) depending on whether the entire transport block has been received correctly. Upon receipt of a NACK the transmitting device may retransmit the full transport block, including information that was correctly received. This may result in a delay in sending subsequent blocks of new information and may thereby decrease throughput of the communication link.
SUMMARY
• Systems, methods, and apparatuses for multiple tri-state hybrid automatic repeat request (HARQ) processes are described. A transmitting device may send a signal including multiple transport blocks corresponding to multiple simultaneous HARQ processes. Additional control information may be used to support the multiple simultaneous HARQ processes. For instance, the additional control information may indicate the number of available HARQ processes, an activity state for each HARQ process (e.g., active new data, active retransmission, or inactive), and the redundancy versions of each HARQ process. In some cases, the additional control information may be included in a downlink grant. A receiving device may then respond with an acknowledgement or negative acknowledgment (ACK/NACK) for each of the transport blocks. The transmitting device may then identify a retransmission status for each HARQ process based on the ACK/NACKs, and transmit new redundancy versions (or new data) to the receiving device.
• A method of communication at a wireless device is described. The method may include identifying a state for each of a plurality of HARQ processes, transmitting a control message including an indication of the state for each of the plurality of HARQ processes, and transmitting a data signal including a plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the control message.
• An apparatus for communication at a wireless device is described. The apparatus may include means for identifying a state for each of a plurality of HARQ processes, means for transmitting a control message including an indication of the state for each of the plurality of HARQ processes, and means for transmitting a data signal including a plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the control message.
• A further apparatus for communication at a wireless device is described. The apparatus may include a processor, memory in electronic communication with the processor, and instructions stored in the memory. The instructions may be executable by the processor to identify a state for each of a plurality of HARQ processes, transmit a control message including an indication of the state for each of the plurality of HARQ processes, and transmit a data signal including a plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the control message.
• A non-transitory computer-readable medium storing code for communication at a wireless device is described. The code may include instructions executable to identify a state for each of a plurality of HARQ processes, transmit a control message including an indication of the state for each of the plurality of HARQ processes, and transmit a data signal including a plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the control message.
• Some examples of the method, apparatuses, or non-transitory computer-readable medium described above may further include processes, features, means, or instructions for receiving a NACK for a transport block of the plurality of transport blocks, and identifying a retransmission status for a HARQ process of the plurality of HARQ processes corresponding to the transport block, and the retransmission status may include a retransmission indication and a redundancy version. Additionally or alternatively, some examples may include processes, features, means, or instructions for transmitting a second control message based at least in part on the retransmission status, and transmitting a second data signal including a second plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the second control message.
• In some examples of the method, apparatuses, or non-transitory computer-readable medium described above, the state for each of the plurality of HARQ processes may include a new data indication, a retransmission indication, or an inactive indication. Additionally or alternatively, in some examples, the state for at least one of the plurality of HARQ processes comprises a redundancy version.
• In some examples of the method, apparatuses, or non-transitory computer-readable medium described above, the control message may include a resource grant for the plurality of transport blocks. Additionally or alternatively, in some examples, each of the plurality of transport blocks utilizes the same modulation and coding scheme (MCS).
• Some examples of the method, apparatuses, or non-transitory computer-readable medium described above may further include processes, features, means, or instructions for identifying a first set of resources for a subset of the plurality of HARQ processes associated with retransmitted data. Additionally or alternatively, some examples may include processes, features, means, or instructions for equally partitioning a second set of resources for the data signal between a plurality of transport blocks containing new data.
• A further method of communication at a wireless device is also described. The method may include receiving a control message including an indication of the state for each of a plurality of HARQ processes, and receiving a data signal including a plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the control message.
• A further apparatus for communication at a wireless device is also described. The apparatus may include means for receiving a control message including an indication of the state for each of a plurality of HARQ processes, and means for receiving a data signal including a plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the control message.
• A further apparatus for communication at a wireless device is also described. The apparatus may include a processor, memory in electronic communication with the processor, and instructions stored in the memory. The instructions may be executable by the processor to receive a control message including an indication of the state for each of a plurality of HARQ processes, and receive a data signal including a plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the control message.
• A non-transitory computer-readable medium storing code for communication at a wireless device is described. The code may include instructions executable to receive a control message including an indication of the state for each of a plurality of HARQ processes, and receive a data signal including a plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the control message.
• Some examples of the method, apparatuses, or non-transitory computer-readable medium described above may further include processes, features, means, or instructions for transmitting a NACK for a transport block of the plurality of transport blocks. Additionally or alternatively, some examples may include processes, features, means, or instructions for receiving a second control message, identifying a retransmission status for a HARQ process of the plurality of HARQ processes corresponding to the transport block based at least in part on the second control message, and the retransmission status may include a retransmission indication and a redundancy version, and receiving a second data signal including a second plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the second control message.
• In some examples of the method, apparatuses, or non-transitory computer-readable medium described above, the state for each of the plurality of HARQ processes comprises a new data indication, a retransmission indication, or an inactive indication. Additionally or alternatively, in some examples, the state for at least one of the plurality of HARQ processes comprises a redundancy version.
• In some examples of the method, apparatuses, or non-transitory computer-readable medium described above, the control message comprises a resource grant for the plurality of transport blocks. Additionally or alternatively, in some examples, each of the plurality of transport blocks utilizes the same MCS.
• The foregoing has outlined rather broadly the features and technical advantages of examples according to the disclosure in order that the detailed description that follows may be better understood. Additional features and advantages will be described hereinafter. The conception and specific examples disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. Such equivalent constructions do not depart from the scope of the appended claims. Characteristics of the concepts disclosed herein, both their organization and method of operation, together with associated advantages will be better understood from the following description when considered in connection with the accompanying figures. Each of the figures is provided for the purpose of illustration and description only, and not as a definition of the limits of the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
• A further understanding of the nature and advantages of the present disclosure may be realized by reference to the following drawings. 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.
• FIG. 1 illustrates an example of a wireless communications system for multiple tri-state hybrid automatic repeat request (HARQ) processes in accordance with various aspects of the present disclosure;
• FIG. 2 illustrates an example of a wireless communications system for multiple tri-state HARQ processes in accordance with various aspects of the present disclosure;
• FIG. 3 illustrates an example of a communications structure for multiple tri-state HARQ processes in accordance with various aspects of the present disclosure;
• FIG. 4 illustrates an example of a process flow for multiple tri-state HARQ processes in accordance with various aspects of the present disclosure;
• FIGS. 5 through 7 show block diagrams of a wireless device configured for multiple tri-state HARQ processes in accordance with various aspects of the present disclosure;
• FIG. 8 illustrates a block diagram of a system including a UE configured for multiple tri-state HARQ processes in accordance with various aspects of the present disclosure;
• FIG. 9 illustrates a block diagram of a system including a base station configured for multiple tri-state HARQ processes in accordance with various aspects of the present disclosure; and
• FIGS. 10 through 15 show flowcharts illustrating a method for multiple tri-state HARQ processes in accordance with various aspects of the present disclosure.
DETAILED DESCRIPTION
• A transmitting device may utilize multiple hybrid automatic repeat request (HARQ) processes corresponding to multiple transport blocks to increase the throughput of a communication link. The multiple HARQ processes may be associated with additional control information. For instance, the additional control information may indicate which HARQ processes are being utilized, the activity state of each HARQ process (e.g., active new data, active retransmission, or inactive), and the redundancy version corresponding to each HARQ process. Common transmission error events may also be handled by the additional control information.
• A HARQ process may include transmission of new data from a transmitting device to a receiving device. The receiving device may respond with an ACK/NACK communicating whether the transmission was correctly received. If the response is an ACK the transmitting device may send a new set of data, and if the response is a NACK the transmitting device may send a redundancy version that may be combined with the first transmission at the receiving device.
• Additional signaling may support use of multiple HARQ processes. In some cases, this additional signaling may be used to signal the HARQ processes utilized by multiple transport blocks, the redundancy version corresponding to a HARQ process, and the activity state of a HARQ processes.
• A device may be given a DL grant to receive data. During the DL grant the HARQ processes may be in one of three states: 1) Active: New Data, 2) Active: Retransmission 3) Inactive. A HARQ process state may be signaled to the device through the Physical Downlink Control Channel (PDCCH). In some cases, all of the HARQ processes in a DL grant may share the same modulation and coding scheme. In other cases, the HARQ processes may have different transport block sizes and if a HARQ process has multiple transport blocks, then each transport block can have a different modulation and coding scheme (MCS).
• In some examples, the number of HARQ processes may be limited to some maximum, K, for instance. The number of ACK/NACKs may then also be limited to K. In some cases, in order to signal the information associated with HARQ processing, K bits may be used for the active or inactive indication. The number of bits used for the activity indication may be independent of the number of code blocks in each HARQ process. K bits may also be used to signify that a HARQ process is sending new data and not a redundant version (i.e., to signify a new data indication (NDI)). The bits used to signify an NDI may be toggled and may allow a device to distinguish between different error events. Densely packing such activity state information may enable the use of as little as K log₂(3) bits to indicate the three activity states that may occur during the HARQ process. An additional 2K bits may be used to signal the redundancy version for each code block. This may allow the redundancy versions to be sent in an arbitrary order. In some examples, a HARQ process supports several codewords (c)—e.g., c>1. In such cases, K bits may be used for each codeword in each of HARQ processes to signify that a HARQ process may send new data rather than redundant information, such that cK bits may be used.
• Transport block sizes for a retransmission may follow the original transmission. The retransmission may have a different modulation and coding scheme than the original. In a given DL grant, after the resource elements (REs) utilized for retransmission have been selected, the remaining REs may be partitioned across the various active HARQ process. In one example, the remaining REs may be equally portioned among the HARQ processes with new data. Additionally or alternatively, extra signaling may be used for unequal partitioning of resources. The partitioning of the REs may determine the transport block size (TBS).
• Certain error events may occur when transmitting multiple HARQ processes. Additional control information (such as the information fields described above) may be utilized to mitigate these errors. In one example, a UE may fail to decode the PDCCH. If the NDI bit is not toggled, the UE may combine the retransmission, otherwise it may clear the log likelihood ratio (LLR) buffer. In another example, the base station may fail to decode the ACK/NACK. If the NDI bit is not toggled, the UE may drop the PDSCH processing and resend the ACK/NACK, otherwise it may clear its buffers. In yet another example, a UE may fail to decode the PDSCH. If the NDI bit is not toggled, the UE may recombine the retransmission, otherwise it may clear the LLR buffer. In still another example, a UE may fail to decode the PDSCH and the base station may fail to decode the ACK/NACK. If the NDI bit is not toggled, the UE may recombine the retransmission, otherwise it may clear the LLR buffer.
• The following description provides examples, and is not limiting of the scope, applicability, or examples set forth in the claims. Changes may be made in the function and arrangement of elements discussed without departing from the scope of the disclosure. Various examples may omit, substitute, or add various procedures or components as appropriate. For instance, the methods described may be performed in an order different from that described, and various steps may be added, omitted, or combined. Also, features described with respect to some examples may be combined in other examples.
• FIG. 1 illustrates an example of awireless communications system100 in accordance with various aspects of the present disclosure. Thewireless communications system100 includesbase stations105, user equipment (UE)115, and acore network130. Thecore network130 may provide user authentication, access authorization, tracking, internet protocol (IP) connectivity, and other access, routing, or mobility functions. Thebase stations105 interface with thecore network130 through backhaul links132 (e.g., S1, etc.). Thebase stations105 may perform radio configuration and scheduling for communication with theUEs115, or may operate under the control of a base station controller (not shown). In various examples, thebase stations105 may communicate, either directly or indirectly (e.g., through core network130), with one another over backhaul links134 (e.g., X1, etc.), which may be wired or wireless communication links.
• Thebase stations105 may wirelessly communicate with theUEs115 via one or more base station antennas. Thebase stations105 may be configured to employ multiple tri-state HARQ process in communications withUEs115. Each of thebase stations105 may provide communication coverage for a respectivegeographic coverage area110. In some examples,base stations105 may be referred to as a base transceiver station, a radio base station, an access point, a radio transceiver, a NodeB, eNodeB (eNB), Home NodeB, a Home eNodeB, or some other suitable terminology. Thegeographic coverage area110 for abase station105 may be divided into sectors making up only a portion of the coverage area (not shown). Thewireless communications system100 may includebase stations105 of different types (e.g., macro or small cell base stations). There may be overlappinggeographic coverage areas110 for different technologies.
• In some examples, thewireless communications system100 is a Long Term Evolution (LTE)/LTE-Advanced (LTE-A) network. In LTE/LTE-A networks, the term evolved node B (eNB) may be generally used to describe thebase stations105, while the term UE may be generally used to describe theUEs115. Thewireless communications system100 may be a heterogeneous LTE/LTE-A network in which different types of eNBs provide coverage for various geographical regions. For example, each eNB orbase station105 may provide communication coverage for a macro cell, a small cell, or other types of cell. The term “cell” is a 3GPP term that can be used to describe a base station, a carrier or component carrier associated with a base station, or a coverage area (e.g., sector, etc.) of a carrier or base station, depending on context.
• A macro cell generally covers a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access byUEs115 with service subscriptions with the network provider. A small cell is a lower-powered base station, as compared with a macro cell, that may operate in the same or different (e.g., licensed, unlicensed, etc.) frequency bands as macro cells. Small cells may include pico cells, femto cells, and micro cells according to various examples. A pico cell, for example, may cover a small geographic area and may allow unrestricted access byUEs115 with service subscriptions with the network provider. A femto cell may also cover a small geographic area (e.g., a home) and may provide restricted access byUEs115 having an association with the femto cell (e.g.,UEs115 in a closed subscriber group (CSG),UEs115 for users in the home, and the like). An eNB for a macro cell may be referred to as a macro eNB. An eNB for a small cell may be referred to as a small cell eNB, a pico eNB, a femto eNB, or a home eNB. An eNB may support one or multiple (e.g., two, three, four, and the like) cells (e.g., component carriers).
• Thewireless communications system100 may support synchronous or asynchronous operation. For synchronous operation, thebase stations105 may have similar frame timing, and transmissions fromdifferent base stations105 may be approximately aligned in time. For asynchronous operation, thebase stations105 may have different frame timing, and transmissions fromdifferent base stations105 may not be aligned in time. The techniques described herein may be used for either synchronous or asynchronous operations.
• TheUEs115 may be dispersed throughout thewireless communications system100, and eachUE115 may be stationary or mobile. MoreoverUEs115 may be configured to employ multiple tri-state HARQ process in communications withbase stations105. AUE115 may also include or be referred to by those skilled in the art as a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless device, a wireless communications device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile client, a client, or some other suitable terminology. AUE115 may be a cellular phone, a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a tablet computer, a laptop computer, a cordless phone, a wireless local loop (WLL) station, or the like. A UE may be able to communicate with various types of base stations and network equipment including macro eNBs, small cell eNBs, relay base stations, and the like.
• The communication links125 shown inwireless communications system100 may include uplink (UL) transmissions from aUE115 to abase station105, or downlink (DL) transmissions, from abase station105 to aUE115. The downlink transmissions may also be called forward link transmissions while the uplink transmissions may also be called reverse link transmissions. Eachcommunication link125 may include one or more carriers, where each carrier may be a signal made up of multiple sub-carriers (e.g., waveform signals of different frequencies) modulated according to the various radio technologies described above. Each modulated signal may be sent on a different sub-carrier and may carry control information (e.g., reference signals, control channels, etc.), overhead information, user data, etc. The communication links125 may transmit bidirectional communications using frequency division duplex (FDD) (e.g., using paired spectrum resources) or time division duplex (TDD) operation (e.g., using unpaired spectrum resources). Frame structures may be defined for FDD (e.g., frame structure type1) and TDD (e.g., frame structure type2).
• Wireless communications system100 may support operation on multiple cells or carriers, a feature which may be referred to as carrier aggregation (CA) or multi-carrier operation. A carrier may also be referred to as a component carrier (CC), a layer, a channel, etc. The terms “carrier,” “component carrier,” “cell,” and “channel” may be used interchangeably herein. AUE115 may be configured with multiple downlink CCs and one or more uplink CCs for carrier aggregation. Carrier aggregation may be used with both FDD and TDD component carriers.
• In some cases,wireless communications system100 may utilize enhanced CCs (eCC). An eCC may be characterized by features, including: flexible bandwidth, variable length TTIs, and modified control channel configuration. In some cases, an eCC may be associated with a carrier aggregation configuration or a dual connectivity configuration (e.g., when multiple serving cells have a suboptimal or non-ideal backhaul link). An eCC may also be configured for use in unlicensed spectrum or shared spectrum (where more than one operator is licensed to use the spectrum). An eCC characterized by flexible bandwidth may include one or more segments that may be utilized byUEs115 that do are not capable of monitoring the whole bandwidth or prefer to use a limited bandwidth (e.g., to conserve power).
• In some cases, an eCC may utilize a variable TTI length and symbol duration. In some cases an eCC may include multiple hierarchical layers associated with the different TTI lengths. For example, TTIs at one hierarchical layer may correspond touniform 1 ms subframes, whereas in a second layer, variable length TTIs may correspond to bursts of short duration symbol periods. In some cases, a shorter symbol duration may also be associated with increased subcarrier spacing. In other examples, the numerology of resources of the eCC may be different from numerology of another CC, which may employ TTIs defined in a version or release of, for example, a particular LTE standard.
• Flexible bandwidth and variable TTIs may be associated with a modified control channel configuration—e.g., an eCC may utilize an enhanced physical downlink control channel (ePDCCH) for DL control information, which may perform some of the functions of the PDCCH described below. In some cases, control channels of an eCC may utilize frequency division multiplexed (FDM) control channels to accommodate flexible bandwidth orUEs115 having differing bandwidth capabilities. Other control channel modifications may include the use of additional control channels—e.g., for eMBMS scheduling or to indicate the length of variable length UL and DL bursts—or control channels transmitted at different intervals. An eCC may also include modified or additional HARQ related control information. For instance, an eCC may support communications utilizing multiple tri-state HARQ processes.
• The communication networks that may accommodate some of the various disclosed examples may be packet-based networks that operate according to a layered protocol stack and data in the user plane may be based on the IP. 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 HARQ to provide retransmission 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 aUE115 and thebase stations105. The RRC protocol layer may also be used forcore network130 support of radio bearers for the user plane data. At the physical (PHY) layer, the transport channels may be mapped to physical channels.
• HARQ may be a method of ensuring that the transport block and the contained data are received correctly over awireless communication link125. HARQ may include a combination of error detection (e.g., using a 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., signal-to-noise conditions). In Incremental Redundancy HARQ, incorrectly received data may be stored in a buffer and combined with subsequent transmissions to improve the overall likelihood of successfully decoding the data. In some cases, redundancy bits are added to each message prior to transmission. This may be especially useful in poor radio conditions. In other cases, redundancy bits are not added to each transmission, but are retransmitted after the transmitter of the original message receives a NACK indicating a failed attempt to decode the information. If a portion of the transport block is not sent correctly the receiving device may respond to the transmitting device with a NACK. After receiving a NACK thebase station105 may re-transmit the entire transport block, including correctly decoded information, and each retransmission of a transport block may be considered a subsequent redundancy version (RV) (i.e., a new transport block isRV0, a first retransmission of the transport block isRV1, etc. . . . ). If the redundancy version exceeds a threshold thebase station105 may abandon transmission of the transport block, and send the transport block back to the RLC to start the process over.
• In some cases, abase station105 may utilize a stop-and-wait transmission technique in which thebase station105 waits for an acknowledgement from aUE115 before sending new data or a re-transmission of a transport block. This process may occur according to pre-determined time intervals and in some cases a transmitter may wait up to 8 ms between a first and subsequent transmission—e.g., there may be up to 7 subframes between the two transmissions. Therefore, if a portion of a transport block, corresponding to a HARQ process, is incorrectly received the transmitter may wait up to 8 ms to retransmit the entire transport block, including the correctly received portions of the transport block. In other examples, such as for eCCs utilizing low latency operations—e.g., TTIs have a duration of an LTE release 8 symbol period—HARQ latency may be less than a subframe.
• In order to fully utilize all of the subframes, or TTIs, a transmitter may use multiple hybrid ARQ processes (e.g., up to 8 processes). In some systems, only one HARQ process is utilized for each transmission and a transmitter may send a different number of redundancy versions for alternating HARQ process depending on channel conditions (e.g.,HARQ process1 may containRV2,HARQ process2 may containRV1, andHARQ process3 may contain RV0). It may be important for thebase station105 andUE115 keep track of the HARQ process, the redundancy version, and new data indicators to ensure proper (e.g., in-order) receipt of the transport blocks and data.
• According to the present disclosure, abase station105 may send a signal including multiple transport blocks corresponding to multiple simultaneous HARQ processes. Additional control information may be used to support the multiple simultaneous HARQ processes. For instance, the additional control information may indicate the number of available HARQ processes, an activity state for each HARQ process (e.g., active new data, active retransmission, or inactive), and the redundancy versions of each HARQ process. In some cases, the additional control information may be included in a downlink grant. AUE115 may then respond with an acknowledgement or negative acknowledgment (ACK/NACK) for each of the transport blocks. Thebase station105 may then identify a retransmission status for each HARQ process based on the ACK/NACKs, and transmit new redundancy versions (or new data) to theUE115.
• FIG. 2 illustrates an example of awireless communications system200 for multiple tri-state HARQ processes in accordance with various aspects of the present disclosure.Wireless communications system200 may include UE115-aand base station105-a, which may be examples of aUE115 and abase station105, respectively, described above with reference toFIG. 1. Base station105-aand UE115-amay communicate with one another viadownlink205 anduplink210 when UE115-ais within coverage area110-a, as generally described above with reference toFIG. 1.Downlink205 may include a set oftransport blocks215 anduplink210 may include individual or group ACK/NACKs220. The set oftransport blocks215 may utilize multiple HARQ processes, which may be associated with an additional HARQ signaling payload.
• In some systems, a wireless device using HARQ may utilize only one HARQ process per transmission. In some examples, however, a wireless device such as base station105-amay transmit multiple transport blocks each utilizing a respective HARQ process to increase the throughput of the communication link. Additional control information may indicate the status of the HARQ process, the redundancy version corresponding to each HARQ process, and the activity state of each HARQ process. As mentioned above, in some cases, a HARQ process may be in one of three activity states: Active—New Data, Active—Retransmission, or Inactive.
• For example, base station105-amay transmit a set oftransport blocks215 that utilize multiple HARQ processes either subsequent to or simultaneously with a DL grant. UE115-amay receive the DL grant, which may include additional signaling to support the transmission of the transport blocks corresponding to multiple HARQ processes. For instance, the DL grant received by UE115-amay include control information indicating the activity state of available HARQ processes, the correspondence between transport blocks and HARQ process, and the corresponding redundancy versions. The HARQ states, in addition to the redundancy version of each HARQ process, may be communicated through a HARQ indicator. The HARQ indicator may be included with the DL grant and may be signaled to UE115-athrough the Physical Downlink Control Channel (PDCCH).
• Additional bits in the PDCCH (or in another control message) may be used to indicate the status of the multiple HARQ processes. For example, a HARQ indicator field may include K bits to indicate if the HARQ process is in the active or inactive state. The number of bits used for the activity indication may be independent of the number of code blocks in each HARQ process. K bits may also be used to signify that a HARQ process is sending new data and not a redundant version (e.g., to signify a new data indication (NDI)). The bits used for an NDI may be toggled and may allow a device to distinguish between different error events. This may result in a total of 2K bits used to indicate the activity state and NDI indicator. In some cases, activity status and the NDI indicator for K HARQ processes may be represented in fewer than 2K bits—e.g., efficient packing may enable the use of as few as K log₂(3) bits. Additionally, 2K additional bits may be used to signal the redundancy version for each HARQ process. This may allow the redundancy versions to be sent in an arbitrary order.
• FIG. 3 illustrates an example of acommunications structure300 for multiple tri-state HARQ processes in accordance with various aspects of the present disclosure.Communications structure300 may illustrate aspects of a transmission between aUE115 and abase station105, as described above with reference toFIGS. 1 and 2.Communications structure300 may include HARQ Processes 1 through K, in addition toredundancy versions 1 through N. HARQ processes 1 through K may correspond to up to K transport blocks. The set of transport blocks may be transmitted within a transmission time interval (TTI). First DL grant315-aand second DL grant315-bmay include HARQ indication information so that aUE115 may decode the transport block. In some examples, a set of ACK/NACKs320 may be transmit by aUE115 throughuplink310 while the set of transport blocks may be transmitted by abase station105 throughdownlink305.
• In one example, abase station105 may send aDL grant315 to aUE115. This grant may alert theUE115 of forthcoming data transmissions and communicate to theUE115 how a data signal will be sent. TheDL grant315 may include information about frequency resources used, the amount of data being sent, and the allocation and modulation scheme used for the set of transport blocks. TheDL grant315 may also include control information used to indicate the activity state of the available HARQ processes, the partitioning of one or more transport blocks across the downlink resources, how a transport block corresponds to a HARQ process, and the redundancy version associated with a HARQ process for a TTI. Thebase station105 may transmit transport blocks based on the first DL grant315-aviadownlink305. Each transport block may correspond to one of the KHARQ processes. In one example, HARQ processesHARQ 1 throughHARQ 3 are active, whileHARQ 4 through HARQ K are inactive. In some cases, the transmission may be an initial data transmission and therefore each transport block may include new data as indicated by redundancy version 0 (e.g., TB1: RV0, TB2: RV0, TB3: RV0). In some cases, thebase station105 may wait some duration (e.g., one or more TTIs) for aUE115 to respond with a corresponding set of ACK/NACKs320 after transmitting. In some cases, the ACK/NACK response may be received during the same TTI as the corresponding data transmission. The set of ACK/NACKs320 may communicate to the base station the successful or unsuccessful receipt and decoding of the set of transport blocks.
• In the example ofFIG. 3, HARQ processesHARQ 1 andHARQ 3 may represent successful transmission and reception of the new data included in transport blocks TB1 and TB3 at aUE115, whileHARQ 2 may experience an error event preventing a successful decoding—e.g., a failed cyclic redundancy check (CRC). Thebase station105 may determine which HARQ processes indicate unsuccessful transmissions based on ACK/NACKs320—e.g., which transport blocks correspond to NACKs—and may allocate resources for transmitting redundancy versions of the corresponding transport blocks. After the resources have been allocated to retransmissions, the remaining resource elements may be partitioned across one or more active HARQ process used for new data transmissions. In some cases, the remaining resource elements are equally partitioned among the HARQ processes with new data. In other cases, the resource elements may be unequally partitioned. This allocation of resource elements across HARQ processes may determine the size of the set of transport blocks. In some cases, additional HARQ processes may be activated, or active HARQ process may be deactivated (not shown).
• Once the resources have been allocated, thebase station105 may send a second DL grant315-bindicating how the second set of transport blocks may be sent. For example, the second DL grant315-bmay allocate a second set of frequency resources to the second set of transport blocks. The second set of frequency resources may be different from the previous set of frequency resources, or the second set of transport blocks may be ordered differently from the previous transmission. A retransmission—e.g., a transmission of a redundancy version—may share the same transport block size as the original transmission, and may be retransmitted with either the same or a different modulation and coding scheme (MCS). TheUE115 may again respond with a set of ACK/NACKs and the base station may again determine successful and unsuccessful HARQ transmissions before transmitting redundant and new data in a subsequent transmission.
• FIG. 4 illustrates an example of aprocess flow400 for multiple tri-state HARQ processes in accordance with various aspects of the present disclosure.Process flow400 may be performed by base station105-band UE115-b, which may be examples of abase station105 and aUE115 described above with reference toFIGS. 1-3. In some examples, base station105-bmay transmit multiple HARQ process within the same TTI to UE115-b. UE115-bmay respond with a group ACK/NACK to signal successful or unsuccessful reception or decoding of the transmitted data.
• Atstep405, base station105-bmay identify the state for each of a plurality of HARQ processes. In some examples, the HARQ state includes a new data indication, a retransmission indication, or an inactive indication. The HARQ state may also include a redundancy version.
• Atstep410, base station105-bmay allocate resource elements to transport blocks based on the state of the active HARQ processes.
• Atstep415, base station105-bmay transmit a control message, which may include an indication of the state of the HARQ processes and a resource grant for the associated transport blocks. The resource grant may communicate to UE115-bwhat frequency resources are being used, the amount of data being sent, and the allocation and modulation and coding scheme (MCS) to be used for the plurality of transport blocks.
• Atstep420, base station105-bmay transmit a data signal to UE115-bincluding the multiple transport blocks. In some examples, each of the plurality of transport blocks utilizes the same MCS. In some examples, the plurality of transport blocks are transmitted within a single TTI. In some cases, each transport block can have a different MCS.
• Atstep425, UE115-bmay decode the received plurality of transport blocks based on the control message. UE115-bmay determine whether each transport block is successfully decoded by performing a CRC.
• Atstep430, UE115-bmay respond to base station105-bwith ACK/NACKs based on whether each transport block was successfully decoded. For example, UE115-bmay transmit a NACK for a transport block after a failure to receive or decode the transport block. UE115-bmay send an ACK for a transport block after successful reception and decoding.
• Atstep435, base station105-bmay update the state of the available HARQ processes based on the ACK/NACKs from UE115-b. The updated state may identify a retransmission status, and may include a retransmission indication or a redundancy version, or both. In some cases, the retransmission status may be the result of base station105-breceiving a NACK. In other cases, the retransmission status may be the result of base station105-bfailing to correctly receive a NACK. In yet other cases, the retransmission status may be the result of UE115-bfailing to send an ACK or NACK.
• Atstep440, base station105-bmay allocate resources for additional transport blocks based on the updated state of the HARQ processes. For example, base station105-bmay identify a first set of resources for HARQ processes associated with retransmitted data. In some cases, base station105-bmay equally partition a second set of resources between those transport blocks containing new data.
• Atstep445, base station105-bmay transmit a second control message including an indication of the updated state of the HARQ processes corresponding to the second set of transport blocks and the new allocation of resources to UE115-b. UE115-bmay then identify the retransmission status for the forthcoming transport blocks based on the second control. UE115-bmay also identify a new data status for the forthcoming transmission.
• Atstep450, base station105-bmay transmit a second data signal including a second set of multiple transport blocks based on the second control message.
• FIG. 5 shows a block diagram of awireless device500 configured for multiple tri-state HARQ processes in accordance with various aspects of the present disclosure.Wireless device500 may be an example of aspects of a device, such as aUE115 orbase station105 described with reference toFIGS. 1-4.Wireless device500 may include areceiver505, a tri-stateHARQ process module510, or atransmitter515.Wireless device500 may also include a processor. Each of these components may be in communication with one another.
• Thereceiver505 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 multiple tri-state HARQ processes, etc.). Information may be passed on to the tri-stateHARQ process module510, and to other components ofwireless device500.
• The tri-stateHARQ process module510 may identify a state for each of a plurality of HARQ processes. The tri-stateHARQ process module510 may also, in combination with other modules, for instance, transmit a control message including an indication of the state for each of the plurality of HARQ processes, and transmit a data signal including a plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the control message.
• Thetransmitter515 may transmit signals received from other components ofwireless device500. In some examples, thetransmitter515 may be collocated with thereceiver505 in a transceiver module. Thetransmitter515 may include a single antenna, or it may include a plurality of antennas.
• FIG. 6 shows a block diagram of awireless device600 for multiple tri-state HARQ processes in accordance with various aspects of the present disclosure.Wireless device600 may be an example of aspects of awireless device500, aUE115 or abase station105 described with reference toFIGS. 1-5.Wireless device600 may include a receiver505-a, a tri-state HARQ process module510-a, or a transmitter515-a.Wireless device600 may also include a processor. Each of these components may be in communication with one another. The tri-state HARQ process module510-amay also include astate module605, acontrol message module610, and adata module615.
• The receiver505-amay receive information which may be passed on to tri-state HARQ process module510-a, and to other components ofwireless device600. The tri-state HARQ process module510-amay perform the operations described above with reference toFIG. 5. The transmitter515-amay transmit signals received from other components ofwireless device600.
• Thestate module605 may identify a state for each of a plurality of HARQ processes as described above with reference toFIGS. 2-4. In some examples, the state for each of the plurality of HARQ processes includes a new data indication, a retransmission indication, or an inactive indication. In some examples, the state for a HARQ processes includes a redundancy version.
• Thecontrol message module610 may transmit (or receive), or causewireless device600 to transmit (or receive), a control message including an indication of the state for each of the plurality of HARQ processes as described above with reference toFIGS. 2-4. Thecontrol message module610 may also transmit a second control message based at least in part on a retransmission status. In some examples, the control message includes a resource grant for the plurality of transport blocks.
• Thedata module615 may transmit (or receive), or causewireless device600 to transmit (or receive), a data signal including a plurality of transport blocks corresponding to a number of HARQ processes, and based on the control message, as described above with reference toFIGS. 2-4. Thedata module615 may also transmit a second data signal including a second plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the second control message.
• FIG. 7 shows a block diagram700 of a tri-state HARQ process module510-bwhich may be a component of awireless device500 or awireless device600 for multiple tri-state HARQ processes in accordance with various aspects of the present disclosure. The tri-state HARQ process module510-bmay be an example of aspects of a tri-stateHARQ process module510 described with reference toFIGS. 5-6. The tri-state HARQ process module510-bmay include a state module605-a, a control message module610-a, and a data module615-a. Each of these modules may perform the functions described above with reference toFIG. 6. The tri-state HARQ process module510-bmay also include an ACK/NACK module705, aretransmission status module710, and aresource module715. The various modules of tri-state HARQ process module510-bmay be in communication with one another.
• The ACK/NACK module705 may transmit (or receive) an ACK or a NACK for each transport block received, as described above with reference toFIGS. 2-4. The ACK/NACK may be sent based on whether a received transport block passes a CRC.
• Theretransmission status module710 may identify a retransmission status for each HARQ process of a plurality of HARQ processes, and the retransmission status may include a retransmission indication and a redundancy version, as described above with reference toFIGS. 2-4. Theretransmission status module710 may also identify a second retransmission status based at least in part on a second control message.
• Theresource module715 may identify a first set of resources for a subset of a plurality of HARQ processes associated with retransmitted data, as described above with reference toFIGS. 2-4. Theresource module715 may also equally partition a second set of resources for a data signal between a plurality of transport blocks containing new data.
• The components ofwireless device500,wireless device600, or tri-state HARQ process module510-bmay each, individually or collectively, be implemented with at least one application specific integrated circuit (ASIC) adapted to perform some or all of the applicable functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores), on at least one IC. In other examples, other types of integrated circuits may be used (e.g., Structured/Platform ASICs, a field programmable gate array (FPGA), or another semi-custom IC), which may be programmed in any manner known in the art. The functions of each unit may also be implemented, in whole or in part, with instructions embodied in a memory, formatted to be executed by one or more general or application-specific processors.
• FIG. 8 shows a diagram of asystem800 including a UE configured for multiple tri-state HARQ processes in accordance with various aspects of the present disclosure.System800 may include UE115-c, which may be an example of awireless device500, awireless device600, or aUE115 described above with reference toFIGS. 1-7. UE115-cmay include a tri-stateHARQ process module810, which may be an example of a tri-stateHARQ process module510 described with reference toFIGS. 5-7. In some examples, UE115-cincludesMCS module825. UE115-cmay also include components for bi-directional voice and data communications including components for transmitting communications and components for receiving communications. For example, UE115-cmay communicate bi-directionally with base station105-cor UE115-d.
• TheMCS module825 may be configured to determine an MCS for each transport block. In some cases, each of a plurality of transport blocks utilizes the same MCS as described above with reference toFIGS. 2-4. In some examples, each of the plurality of transport blocks utilizes the same MCS.
• UE115-cmay also include aprocessor805, and memory815 (including software (SW)820), atransceiver module835, and one or more antenna(s)840, each of which may communicate, directly or indirectly, with one another (e.g., via buses845). Thetransceiver module835 may communicate bi-directionally, via the antenna(s)840 or wired or wireless links, with one or more networks, as described above. For example, thetransceiver module835 may communicate bi-directionally with abase station105 or anotherUE115. Thetransceiver module835 may include a modem to modulate the packets and provide the modulated packets to the antenna(s)840 for transmission, and to demodulate packets received from the antenna(s)840. While UE115-cmay include asingle antenna840, UE115-cmay also havemultiple antennas840 capable of concurrently transmitting or receiving multiple wireless transmissions.
• Thememory815 may include random access memory (RAM) and read only memory (ROM). Thememory815 may store computer-readable, computer-executable software/firmware code820 including instructions that, when executed, cause theprocessor805 to perform various functions described herein (e.g., multiple tri-state HARQ processes, etc.). Alternatively, the software/firmware code820 may not be directly executable by theprocessor805 but cause a computer (e.g., when compiled and executed) to perform functions described herein. Theprocessor805 may include an intelligent hardware device, (e.g., a central processing unit (CPU), a microcontroller, an ASIC, etc.)
• FIG. 9 shows a diagram of asystem900 including a base station configured for multiple tri-state HARQ processes in accordance with various aspects of the present disclosure.System900 may include base station105-e, which may be an example of awireless device500, awireless device600, or abase station105 described above with reference toFIGS. 1-8. Base station105-dmay include a base station tri-stateHARQ process module910, which may be an example of a base station tri-stateHARQ process module910 described with reference toFIGS. 6-8. Base station105-dmay also include components for bi-directional voice and data communications including components for transmitting communications and components for receiving communications. For example, base station105-dmay communicate bi-directionally with base station105-eand base station105-for UE115-eand UE115-f.
• In some cases, base station105-dmay have one or more wired backhaul links. Base station105-dmay have a wired backhaul link (e.g., S1 interface, etc.) to thecore network130. Base station105-dmay also communicate withother base stations105, such as base station105-eand base station105-fvia inter-base station backhaul links (e.g., an X2 interface). Each of thebase stations105 may communicate withUEs115 using the same or different wireless communications technologies. In some cases, base station105-dmay communicate with other base stations such as105-dor105-eutilizing basestation communication module925. In some examples, basestation communication module925 may provide an X2 interface within an LTE/LTE-A wireless communication network technology to provide communication between some of thebase stations105. In some examples, base station105-dmay communicate with other base stations throughcore network130. Additionally or alternatively, base station105-dmay communicate with thecore network130 throughnetwork communications module930.
• The base station105-dmay include aprocessor905, memory915 (including software (SW)920),transceiver modules935, and antenna(s)940, which each may be in communication, directly or indirectly, with one another (e.g., over bus system945). Thetransceiver modules935 may be configured to communicate bi-directionally, via the antenna(s)940, with theUEs115, which may be multi-mode devices. The transceiver module935 (or other components of the base station105-d) may also be configured to communicate bi-directionally, via theantennas940, with one or more other base stations (not shown). Thetransceiver module935 may include a modem configured to modulate the packets and provide the modulated packets to theantennas940 for transmission, and to demodulate packets received from theantennas940. The base station105-dmay includemultiple transceiver modules935, each with one or more associatedantennas940. The transceiver module may be an example of a combinedreceiver505 andtransmitter515 ofFIG. 5.
• Thememory915 may include RAM and ROM. Thememory915 may also store computer-readable, computer-executable software code920 containing instructions that are configured to, when executed, cause theprocessor905 to perform various functions described herein (e.g., multiple tri-state HARQ processes, selecting coverage enhancement techniques, call processing, database management, message routing, etc.). Alternatively, thesoftware920 may not be directly executable by theprocessor905 but be configured to cause the computer, e.g., when compiled and executed, to perform functions described herein. Theprocessor905 may include an intelligent hardware device, e.g., a CPU, a microcontroller, an ASIC, etc. Theprocessor905 may include various special purpose processors such as encoders, queue processing modules, base band processors, radio head controllers, digital signal processor (DSPs), and the like.
• The basestation communications module925 may manage communications withother base stations105. The communications management module may include a controller or scheduler for controlling communications withUEs115 in cooperation withother base stations105. For example, the basestation communications module925 may coordinate scheduling for transmissions to UEs115 for various interference mitigation techniques such as beamforming or joint transmission.
• FIG. 10 shows a flowchart illustrating amethod1000 for multiple tri-state HARQ processes in accordance with various aspects of the present disclosure. The operations ofmethod1000 may be implemented by a wireless device such as aUE115 orbase station105 or their components, which may includewireless device500 orwireless device600, as described with reference toFIGS. 1-9. For example, the operations ofmethod1000 may be performed by the tri-stateHARQ process module510 as described with reference toFIGS. 5-8. In some examples, a device may execute a set of codes to control the functional elements of the device to perform the functions described below. Additionally or alternatively, the device may perform aspects of the functions described below using special-purpose hardware.
• Atblock1005, the device may identify a state for each of a plurality of HARQ processes as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1005 may be performed by thestate module605 as described above with reference toFIG. 6.
• Atblock1010, the device may transmit a control message including an indication of the state for each of the plurality of HARQ processes as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1010 may be performed by thecontrol message module610 as described above with reference toFIG. 6.
• Atblock1015, the device may transmit a data signal including a plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the control message as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1015 may be performed by thedata module615 as described above with reference toFIG. 6.
• FIG. 11 shows a flowchart illustrating amethod1100 for multiple tri-state HARQ processes in accordance with various aspects of the present disclosure. The operations ofmethod1100 may be implemented by a wireless device such as aUE115 orbase station105 or their components, which may includewireless device500 orwireless device600, as described with reference toFIGS. 1-9. For example, the operations ofmethod1100 may be performed by the tri-stateHARQ process module510 as described with reference toFIGS. 5-8. In some examples, a device may execute a set of codes to control the functional elements of the device to perform the functions described below. Additionally or alternatively, the device may perform aspects the functions described below using special-purpose hardware. Themethod1100 may also incorporate aspects ofmethod1000 ofFIG. 10.
• Atblock1105, the device may identify a state for each of a plurality of HARQ processes as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1105 may be performed by thestate module605 as described above with reference toFIG. 6.
• Atblock1110, the device may transmit a control message including an indication of the state for each of the plurality of HARQ processes as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1110 may be performed by thecontrol message module610 as described above with reference toFIG. 6.
• Atblock1115, the device may transmit a data signal including a plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the control message as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1115 may be performed by thedata module615 as described above with reference toFIG. 6.
• Atblock1120, the device may receive a NACK for a transport block of the plurality of transport blocks as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1120 may be performed by the ACK/NACK module705 as described above with reference toFIG. 7.
• Atblock1125, the device may identify a retransmission status for a HARQ process of the plurality of HARQ processes corresponding to the transport block, and the retransmission status may include a retransmission indication and a redundancy version as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1125 may be performed by theretransmission status module710 as described above with reference toFIG. 7.
• FIG. 12 shows a flowchart illustrating amethod1200 for multiple tri-state HARQ processes in accordance with various aspects of the present disclosure. The operations ofmethod1200 may be implemented by a wireless device such as aUE115 orbase station105 or their components, which may includewireless device500 orwireless device600, as described with reference toFIGS. 1-9. For example, the operations ofmethod1200 may be performed by the tri-stateHARQ process module510 as described with reference toFIGS. 5-8. In some examples, a device may execute a set of codes to control the functional elements of the device to perform the functions described below. Additionally or alternatively, the device may perform aspects the functions described below using special-purpose hardware. Themethod1200 may also incorporate aspects ofmethods1000 or1100 ofFIGS. 10 and 11.
• Atblock1205, the device may identify a state for each of a plurality of HARQ processes as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1205 may be performed by thestate module605 as described above with reference toFIG. 6.
• Atblock1210, the device may transmit a control message including an indication of the state for each of the plurality of HARQ processes as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1210 may be performed by thecontrol message module610 as described above with reference toFIG. 6.
• Atblock1215, the device may transmit a data signal including a plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the control message as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1215 may be performed by thedata module615 as described above with reference toFIG. 6.
• Atblock1220, the device may receive a NACK for a transport block of the plurality of transport blocks as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1220 may be performed by the ACK/NACK module705 as described above with reference toFIG. 7.
• Atblock1225, the device may identify a retransmission status for a HARQ process of the plurality of HARQ processes corresponding to the transport block, and the retransmission status may include a retransmission indication and a redundancy version as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1225 may be performed by theretransmission status module710 as described above with reference toFIG. 7.
• Atblock1230, the device may transmit a second control message based at least in part on the retransmission status as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1230 may be performed by thecontrol message module610 as described above with reference toFIG. 6.
• Atblock1235, the device may transmit a second data signal including a second plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the second control message as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1235 may be performed by thedata module615 as described above with reference toFIG. 6.
• FIG. 13 shows a flowchart illustrating amethod1300 for multiple tri-state HARQ processes in accordance with various aspects of the present disclosure. The operations ofmethod1300 may be implemented by a wireless device such as aUE115 orbase station105 or their components, which may includewireless device500 orwireless device600, as described with reference toFIGS. 1-9. For example, the operations ofmethod1300 may be performed by the tri-stateHARQ process module510 as described with reference toFIGS. 5-8. In some examples, a device may execute a set of codes to control the functional elements of the device to perform the functions described below. Additionally or alternatively, the device may perform aspects the functions described below using special-purpose hardware.
• Atblock1305, the device may receive a control message including an indication of the state for each of a plurality of HARQ processes as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1305 may be performed by thecontrol message module610 as described above with reference toFIG. 6.
• Atblock1310, the device may receive a data signal including a plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the control message as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1310 may be performed by thedata module615 as described above with reference toFIG. 6.
• FIG. 14 shows a flowchart illustrating amethod1400 for multiple tri-state HARQ processes in accordance with various aspects of the present disclosure. The operations ofmethod1400 may be implemented by a wireless device such as aUE115 orbase station105 or their components, which may includewireless device500 orwireless device600, as described with reference toFIGS. 1-9. For example, the operations ofmethod1400 may be performed by the tri-stateHARQ process module510 as described with reference toFIGS. 5-8. In some examples, a device may execute a set of codes to control the functional elements of the device to perform the functions described below. Additionally or alternatively, the device may perform aspects the functions described below using special-purpose hardware. Themethod1400 may also incorporate aspects ofmethods1300 ofFIG. 13.
• Atblock1405, the device may receive a control message including an indication of the state for each of a plurality of HARQ processes as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1405 may be performed by thecontrol message module610 as described above with reference toFIG. 6.
• Atblock1410, the device may receive a data signal including a plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the control message as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1410 may be performed by thedata module615 as described above with reference toFIG. 6.
• Atblock1415, the device may transmit a NACK for a transport block of the plurality of transport blocks as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1415 may be performed by the ACK/NACK module705 as described above with reference toFIG. 7.
• FIG. 15 shows a flowchart illustrating amethod1500 for multiple tri-state HARQ processes in accordance with various aspects of the present disclosure. The operations ofmethod1500 may be implemented by a wireless device such as aUE115 orbase station105 or their components, which may includewireless device500 orwireless device600, as described with reference toFIGS. 1-9. For example, the operations ofmethod1500 may be performed by the tri-stateHARQ process module510 as described with reference toFIGS. 5-8. In some examples, a device may execute a set of codes to control the functional elements of the device to perform the functions described below. Additionally or alternatively, the device may perform aspects the functions described below using special-purpose hardware. Themethod1500 may also incorporate aspects ofmethods1300 or1400 ofFIGS. 13 and 14.
• Atblock1505, the device may receive a control message including an indication of the state for each of a plurality of HARQ processes as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1505 may be performed by thecontrol message module610 as described above with reference toFIG. 6.
• Atblock1510, the device may receive a data signal including a plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the control message as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1510 may be performed by thedata module615 as described above with reference toFIG. 6.
• Atblock1515, the device may transmit a NACK for a transport block of the plurality of transport blocks as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1515 may be performed by the ACK/NACK module705 as described above with reference toFIG. 7.
• Atblock1520, the device may receive a second control message as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1520 may be performed by thecontrol message module610 as described above with reference toFIG. 6.
• Atblock1525, the device may identify a retransmission status for a HARQ process of the plurality of HARQ processes corresponding to the transport block based at least in part on the second control message, and the retransmission status may include a retransmission indication and a redundancy version as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1525 may be performed by theretransmission status module710 as described above with reference toFIG. 7.
• Atblock1530, the device may receive a second data signal including a second plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the second control message as described above with reference toFIGS. 2-4. In certain examples, the operations ofblock1530 may be performed by thedata module615 as described above with reference toFIG. 6.
• Thus,methods1000,1100,1200,1300,1400, and1500 may provide for multiple tri-state HARQ processes. It should be noted thatmethods1000,1100,1200,1300,1400, and1500 describe possible implementation, and that the operations and the steps may be rearranged or otherwise modified such that other implementations are possible. In some examples, aspects from two or more of themethods1000,1100,1200,1300,1400, and1500 may be combined.
• The detailed description set forth above 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 “exemplary,” as may be 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, well-known structures and devices are shown in block diagram form in order to avoid obscuring the concepts of the described examples.
• Information and signals 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 above 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 modules described in connection with the disclosure herein may be implemented or performed with a general-purpose processor, a DSP, an ASIC, 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 conventional 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 above can 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. Also, as used herein, including in the claims, “or” as used in a list of items (for example, 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).
• All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. The words “module,” “mechanism,” “element,” “device,” and the like may not be a substitute for the word “means.” As such, no claim element is to be construed as a means plus function unless the element is expressly recited using the phrase “means for.”
• 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 can be accessed by a general purpose or special purpose computer. By way of example, and not limitation, non-transitory computer-readable media can comprise RAM, ROM, electrically erasable programmable read only memory (EEPROM), compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that can be used to carry or store desired program code means in the form of instructions or data structures and that can 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 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.
• The previous description of the disclosure is provided to enable a person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be readily apparent to those skilled 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 to be 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.
• Techniques described herein may be used for various wireless communications systems such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal frequency division multiple access (OFDMA), single carrier frequency division multiple access (SC-FDMA), and other systems. The terms “system” and “network” are often used interchangeably. A CDMA system may implement a radio technology such as CDMA2000, Universal Terrestrial Radio Access (UTRA), etc. CDMA2000 covers IS-2000, IS-95, and IS-856 standards. IS-2000Releases 0 and A are commonly referred to asCDMA2000 1×, 1×, etc. IS-856 (TIA-856) is commonly referred to asCDMA2000 1×EV-DO, High Rate Packet Data (HRPD), etc. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. A TDMA system may implement a radio technology such as Global System for Mobile Communications (GSM). An OFDMA system may implement a radio technology such as Ultra Mobile Broadband (UMB), Evolved UTRA (E-UTRA), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, etc. UTRA and E-UTRA are part of Universal Mobile Telecommunications system (UMTS). 3GPP Long Term Evolution (LTE) and LTE-Advanced (LTE-A) are new releases of Universal Mobile Telecommunications System (UMTS) that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, and Global System for Mobile communications (GSM) are described in documents from an organization named “3rd Generation Partnership Project” (3GPP). CDMA2000 and UMB are described in documents from an organization named “3rdGeneration Partnership Project 2” (3GPP2). The techniques described herein may be used for the systems and radio technologies mentioned above as well as other systems and radio technologies. The description above, however, describes an LTE system for purposes of example, and LTE terminology is used in much of the description above, although the techniques are applicable beyond LTE applications.

Claims (28)

What is claimed is:

1. A method for wireless communications at a wireless device, comprising:

receiving a control message comprising an indication of a state for each of a plurality of hybrid automatic repeat request (HARQ) processes; and

receiving a data signal comprising a plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the control message.

2. The method ofclaim 1, further comprising:

transmitting a negative acknowledgement (NACK) for a transport block of the plurality of transport blocks.

3. The method ofclaim 2, further comprising:

receiving a second control message;

identifying a retransmission status for a HARQ process of the plurality of HARQ processes corresponding to the transport block based at least in part on the second control message, wherein the retransmission status comprises a retransmission indication and a redundancy version; and

receiving a second data signal comprising a second plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the second control message.

4. The method ofclaim 1, wherein the state for each of the plurality of HARQ processes comprises a new data indication, a retransmission indication, or an inactive indication.

5. The method ofclaim 1, wherein the state for at least one of the plurality of HARQ processes comprises a redundancy version.

6. The method ofclaim 1, wherein the control message comprises a resource grant for the plurality of transport blocks.

7. The method ofclaim 1, wherein each of the plurality of transport blocks utilizes a same modulation and coding scheme (MCS).

8. An apparatus for wireless communications at a wireless device, comprising:

a processor,

memory coupled with the processor; and

instructions stored in the memory and executable by the processor to cause the apparatus to:

receive a control message comprising an indication of a state for each of a plurality of hybrid automatic repeat request (HARQ) processes; and

receive a data signal comprising a plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the control message.

9. The apparatus ofclaim 8, wherein the instructions are further executable by the processor to cause the apparatus to:

transmit a negative acknowledgement (NACK) for a transport block of the plurality of transport blocks.

10. The apparatus ofclaim 9, wherein the instructions are further executable by the processor to cause the apparatus to:

receive a second control message;

identify a retransmission status for a HARQ process of the plurality of HARQ processes corresponding to the transport block based at least in part on the second control message, wherein the retransmission status comprises a retransmission indication and a redundancy version; and

receive a second data signal comprising a second plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the second control message.

11. The apparatus ofclaim 8, wherein the state for each of the plurality of HARQ processes comprises a new data indication, a retransmission indication, or an inactive indication.

12. The apparatus ofclaim 8, wherein the state for at least one of the plurality of HARQ processes comprises a redundancy version.

13. The apparatus ofclaim 8, wherein the control message comprises a resource grant for the plurality of transport blocks.

14. The apparatus ofclaim 8, wherein each of the plurality of transport blocks utilizes a same modulation and coding scheme (MCS).

15. An apparatus for wireless communications at a wireless device, comprising:

means for receiving a control message comprising an indication of a state for each of a plurality of hybrid automatic repeat request (HARQ) processes; and

means for receiving a data signal comprising a plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the control message.

16. The apparatus ofclaim 15, further comprising:

means for transmitting a negative acknowledgement (NACK) for a transport block of the plurality of transport blocks.

17. The apparatus ofclaim 16, further comprising:

means for receiving a second control message;

means for identifying a retransmission status for a HARQ process of the plurality of HARQ processes corresponding to the transport block based at least in part on the second control message, wherein the retransmission status comprises a retransmission indication and a redundancy version; and

means for receiving a second data signal comprising a second plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the second control message.

18. The apparatus ofclaim 15, wherein the state for each of the plurality of HARQ processes comprises a new data indication, a retransmission indication, or an inactive indication.

19. The apparatus ofclaim 15, wherein the state for at least one of the plurality of HARQ processes comprises a redundancy version.

20. The apparatus ofclaim 15, wherein the control message comprises a resource grant for the plurality of transport blocks.

21. The apparatus ofclaim 15, wherein each of the plurality of transport blocks utilizes a same modulation and coding scheme (MCS).

22. A non-transitory computer-readable medium storing code for wireless communications at a wireless device, the code comprising instructions executable by a processor to:

receive a control message comprising an indication of a state for each of a plurality of hybrid automatic repeat request (HARQ) processes; and

receive a data signal comprising a plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the control message.

23. The non-transitory computer-readable medium ofclaim 22, wherein the instructions are further executable to:

transmit a negative acknowledgement (NACK) for a transport block of the plurality of transport blocks.

24. The non-transitory computer-readable medium ofclaim 23, wherein the instructions are further executable to:

receive a second control message;

identify a retransmission status for a HARQ process of the plurality of HARQ processes corresponding to the transport block based at least in part on the second control message, wherein the retransmission status comprises a retransmission indication and a redundancy version; and

receive a second data signal comprising a second plurality of transport blocks corresponding to the plurality of HARQ processes based at least in part on the second control message.

25. The non-transitory computer-readable medium ofclaim 22, wherein the state for each of the plurality of HARQ processes comprises a new data indication, a retransmission indication, or an inactive indication.

26. The non-transitory computer-readable medium ofclaim 22, wherein the state for at least one of the plurality of HARQ processes comprises a redundancy version.

27. The non-transitory computer-readable medium ofclaim 22, wherein the control message comprises a resource grant for the plurality of transport blocks.

28. The non-transitory computer-readable medium ofclaim 22, wherein each of the plurality of transport blocks utilizes a same modulation and coding scheme (MCS).

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