WO2023086704A1

WO2023086704A1 - Hybrid automatic repeat request feedback techniques for wireless communications systems

Info

Publication number: WO2023086704A1
Application number: PCT/US2022/077097
Authority: WO
Inventors: Ahmed Elshafie; Hung Dinh LY; Alexandros MANOLAKOS; Yuchul Kim
Original assignee: Qualcomm Incorporated
Priority date: 2021-11-15
Filing date: 2022-09-27
Publication date: 2023-05-19

Abstract

Methods, systems, and devices for wireless communications are described. For example, a wireless device may support hybrid automatic repeat request feedback techniques. In some cases, a wireless device may transmit an indication of a quantity of feedback processes supported and a retention duration associated with the quantity of feedback processes, wherein the retention duration corresponds to a time period during which the wireless device stores decoding information of received packet data for a feedback process. In some examples, a wireless device may transmit an indication of dropped decoding information prior to expiration of a retention duration. Similarly, a wireless device may transmit a report of feedback process for which decoding information is stored. In some cases, a wireless device may indicate a capability to support a threshold quantity of code blocks per transport block within a duration of time.

Description

HYBRID AUTOMATIC REPEAT REQUEST FEEDBACK TECHNIQUES FOR WIRELESS COMMUNICATIONS SYSTEMS

CROSS REFERENCES

[0001] The present Application for Patent claims priority to Greek Patent Application No. 20210100794 by ELSHAFIE et al., entitled “HYBRID AUTOMATIC REPEAT REQUEST FEEDBACK TECHNIQUES FOR WIRELESS COMMUNICATIONS,” filed March 15, 2022; which is assigned to the assignee hereof and expressly incorporated by reference herein.

FIELD OF TECHNOLOGY

[0002] The following relates to wireless communications, including hybrid automatic repeat request feedback techniques for wireless communications systems.

BACKGROUND

[0003] 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 FDMA (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). In some systems, wireless devices may have relatively limited capabilities. In such examples, the wireless devices may be unable to support conventional feedback processes, which may result in poor communications efficiency, or user experience, reduced battery life, or a combination thereof. SUMMARY

[0004] The described techniques relate to improved methods, systems, devices, and apparatuses that support hybrid automatic repeat request (HARQ) feedback techniques for wireless communications systems. Generally, the described techniques provide for capability signaling associated with feedback processes, processing thresholds, or a combination thereof. For example, a first device may transmit, to a second device, control signaling indicating a capability to support a quantity of feedback processes and a retention duration associated with the feedback processes, groups of feedback processes (e.g., a first group corresponding to a first quantity of processes and a first retention duration, a second group corresponding to a second quantity of processes and a second retention duration, etc.). The second device may communicate based on the control signaling. For example, the second device may transmit self-decodable or nonself-decodable retransmissions of packets based on whether the retention duration for the packet (e.g., the retention duration for a feedback process group corresponding to the packet) has expired. Additionally or alternatively, the first device may transmit an indication of a threshold quantity of code blocks per transport block within a duration of time that is supported at the first device. The second device may account for the threshold quantity when scheduling communications with the first device. Such techniques may improve communications efficiency and/or reliability of the system, improve battery life or other performance metrics at the devices, or any combination thereof.

[0005] A method for wireless communications at a first wireless device is described. The method may include transmitting, to a second wireless device, control signaling indicating a quantity of feedback processes supported by the first wireless device and a retention duration associated with the quantity of feedback processes, where the retention duration corresponds to a time period during which the first wireless device stores decoding information of received packet data for a feedback process, transmitting a feedback message indicating unsuccessful decoding of a packet associated with a first feedback process of the quantity of feedback processes, receiving a control message scheduling a retransmission of the packet in accordance with the control signaling, and receiving the retransmission of the packet based on the control message. [0006] An apparatus for wireless communications at a first wireless device is described. The apparatus may include a processor, memory coupled with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to transmit, to a second wireless device, control signaling indicating a quantity of feedback processes supported by the first wireless device and a retention duration associated with the quantity of feedback processes, where the retention duration corresponds to a time period during which the first wireless device stores decoding information of received packet data for a feedback process, transmit a feedback message indicating unsuccessful decoding of a packet associated with a first feedback process of the quantity of feedback processes, receive a control message scheduling a retransmission of the packet in accordance with the control signaling, and receive the retransmission of the packet based on the control message.

[0007] Another apparatus for wireless communications at a first wireless device is described. The apparatus may include means for transmitting, to a second wireless device, control signaling indicating a quantity of feedback processes supported by the first wireless device and a retention duration associated with the quantity of feedback processes, where the retention duration corresponds to a time period during which the first wireless device stores decoding information of received packet data for a feedback process, means for transmitting a feedback message indicating unsuccessful decoding of a packet associated with a first feedback process of the quantity of feedback processes, means for receiving a control message scheduling a retransmission of the packet in accordance with the control signaling, and means for receiving the retransmission of the packet based on the control message.

[0008] A non-transitory computer-readable medium storing code for wireless communications at a first wireless device is described. The code may include instructions executable by a processor to transmit, to a second wireless device, control signaling indicating a quantity of feedback processes supported by the first wireless device and a retention duration associated with the quantity of feedback processes, where the retention duration corresponds to a time period during which the first wireless device stores decoding information of received packet data for a feedback process, transmit a feedback message indicating unsuccessful decoding of a packet associated with a first feedback process of the quantity of feedback processes, receive a control message scheduling a retransmission of the packet in accordance with the control signaling, and receive the retransmission of the packet based on the control message.

[0009] In some examples of the method, apparatuses, and non-transitory computer- readable medium described herein, receiving the control message may include operations, features, means, or instructions for receiving the control message scheduling the retransmission of the packet that includes self-decodable data based on the retransmission of the packet being scheduled outside the time period or non-self- decodable data based on the retransmission of the packet being scheduled within the time period.

[0010] In some examples of the method, apparatuses, and non-transitory computer- readable medium described herein, the decoding information includes log likelihood ratio information for the packet.

[0011] Some examples of the method, apparatuses, and non-transitory computer- readable medium described herein may further include operations, features, means, or instructions for receiving second control signaling indicating resources associated with reporting that the first wireless device may have dropped the decoding information and transmitting, via the indicated resources, an indication that the first wireless device may have dropped the decoding information prior to an expiration of the retention duration.

[0012] Some examples of the method, apparatuses, and non-transitory computer- readable medium described herein may further include operations, features, means, or instructions for receiving a message requesting that the first wireless device report a subset of feedback processes of the quantity of feedback processes for which the first wireless device may be storing respective decoding information and transmitting an indication of the subset of feedback processes to the second wireless device.

[0013] In some examples of the method, apparatuses, and non-transitory computer- readable medium described herein, transmitting the control signaling may include operations, features, means, or instructions for transmitting the control signaling indicating a first group of feedback processes including the quantity of feedback processes, a second group of feedback processes, the retention duration corresponding to the first group of feedback processes, and a second retention duration corresponding to the second group of feedback processes. [0014] In some examples of the method, apparatuses, and non-transitory computer- readable medium described herein, the retention duration includes a first quantity of slots during which the first wireless device stores decoding information for the first group of feedback processes and the second retention duration includes a second quantity of slots during which the first wireless device stores decoding information for the second group of feedback processes.

[0015] In some examples of the method, apparatuses, and non-transitory computer- readable medium described herein, the control signaling indicates a set of multiple groups including the first group and the second group, each group of the set of multiple groups corresponding to a respective retention duration.

[0016] Some examples of the method, apparatuses, and non-transitory computer- readable medium described herein may further include operations, features, means, or instructions for receiving the packet associated with the first feedback process based on the first feedback process being assigned to a first group of feedback processes including the quantity of feedback processes.

[0017] In some examples of the method, apparatuses, and non-transitory computer- readable medium described herein, receiving the control message may include operations, features, means, or instructions for receiving the control message indicating a group identifier associated with the packet, the group identifier corresponding to the quantity of feedback processes and the retention duration.

[0018] Some examples of the method, apparatuses, and non-transitory computer- readable medium described herein may further include operations, features, means, or instructions for receiving a second control message indicating a second group identifier for the packet, the second group identifier associated with a second quantity of feedback processes, a second retention duration, or any combination thereof and receiving a second retransmission of the packet in accordance with the second control message.

[0019] Some examples of the method, apparatuses, and non-transitory computer- readable medium described herein may further include operations, features, means, or instructions for transmitting, in response to the control message, an acknowledgement for the first feedback process based on the first wireless device storing first decoding information for the packet. [0020] A method for wireless communications at a second wireless device is described. The method may include receiving, from a first wireless device, control signaling indicating a quantity of feedback processes supported by the first wireless device and a retention duration associated with the quantity of feedback processes, where the retention duration corresponds to a time period during which the first wireless device stores decoding information of received packet data for a feedback process, receiving a feedback message indicating unsuccessful decoding of a packet associated with a first feedback process of the quantity of feedback processes, transmitting a control message scheduling a retransmission of the packet in accordance with the control signaling, and transmitting the retransmission of the packet based on the control message.

[0021] An apparatus for wireless communications at a second wireless device is described. The apparatus may include a processor, memory coupled with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to receive, from a first wireless device, control signaling indicating a quantity of feedback processes supported by the first wireless device and a retention duration associated with the quantity of feedback processes, where the retention duration corresponds to a time period during which the first wireless device stores decoding information of received packet data for a feedback process, receive a feedback message indicating unsuccessful decoding of a packet associated with a first feedback process of the quantity of feedback processes, transmit a control message scheduling a retransmission of the packet in accordance with the control signaling, and transmit the retransmission of the packet based on the control message.

[0022] Another apparatus for wireless communications at a second wireless device is described. The apparatus may include means for receiving, from a first wireless device, control signaling indicating a quantity of feedback processes supported by the first wireless device and a retention duration associated with the quantity of feedback processes, where the retention duration corresponds to a time period during which the first wireless device stores decoding information of received packet data for a feedback process, means for receiving a feedback message indicating unsuccessful decoding of a packet associated with a first feedback process of the quantity of feedback processes, means for transmitting a control message scheduling a retransmission of the packet in accordance with the control signaling, and means for transmitting the retransmission of the packet based on the control message.

[0023] A non-transitory computer-readable medium storing code for wireless communications at a second wireless device is described. The code may include instructions executable by a processor to receive, from a first wireless device, control signaling indicating a quantity of feedback processes supported by the first wireless device and a retention duration associated with the quantity of feedback processes, where the retention duration corresponds to a time period during which the first wireless device stores decoding information of received packet data for a feedback process, receive a feedback message indicating unsuccessful decoding of a packet associated with a first feedback process of the quantity of feedback processes, transmit a control message scheduling a retransmission of the packet in accordance with the control signaling, and transmit the retransmission of the packet based on the control message.

[0024] In some examples of the method, apparatuses, and non-transitory computer- readable medium described herein, transmitting the control message may include operations, features, means, or instructions for transmitting the control message scheduling the retransmission of the packet that includes self-decodable data based on the retransmission of the packet being scheduled outside the time period or non-self- decodable data based on the retransmission of the packet being scheduled within the time period.

[0025] In some examples of the method, apparatuses, and non-transitory computer- readable medium described herein, the decoding information includes log likelihood ratio information for the packet.

[0026] Some examples of the method, apparatuses, and non-transitory computer- readable medium described herein may further include operations, features, means, or instructions for transmitting second control signaling indicating resources associated with reporting that the first wireless device may have dropped the decoding information and receiving, via the indicated resources, an indication that the first wireless device may have dropped the decoding information prior to an expiration of the retention duration. [0027] Some examples of the method, apparatuses, and non-transitory computer- readable medium described herein may further include operations, features, means, or instructions for transmitting a message requesting that the first wireless device report a subset of feedback processes of the quantity of feedback processes for which the first wireless device may be storing respective decoding information and receiving an indication of the subset of feedback processes from the first wireless device.

[0028] In some examples of the method, apparatuses, and non-transitory computer- readable medium described herein, receiving the control signaling may include operations, features, means, or instructions for receiving the control signaling indicating a first group of feedback processes including the quantity of feedback processes, a second group of feedback processes, the retention duration corresponding to the first group of feedback processes, and a second retention duration corresponding to the second group of feedback processes.

[0029] In some examples of the method, apparatuses, and non-transitory computer- readable medium described herein, the retention duration includes a first quantity of slots during which the first wireless device stores decoding information for the first group of feedback processes and the second retention duration includes a second quantity of slots during which the first wireless device stores decoding information for the second group of feedback processes.

[0030] In some examples of the method, apparatuses, and non-transitory computer- readable medium described herein, the control signaling indicates a set of multiple groups including the first group and the second group, each group of the set of multiple groups corresponding to a respective retention duration.

[0031] Some examples of the method, apparatuses, and non-transitory computer- readable medium described herein may further include operations, features, means, or instructions for transmitting the packet associated with the first feedback process based on the first feedback process being assigned to a first group of feedback processes including the quantity of feedback processes.

[0032] In some examples of the method, apparatuses, and non-transitory computer- readable medium described herein, transmitting the control message may include operations, features, means, or instructions for transmitting the control message indicating a group identifier associated with the packet, the group identifier corresponding to the quantity of feedback processes and the retention duration.

[0033] Some examples of the method, apparatuses, and non-transitory computer- readable medium described herein may further include operations, features, means, or instructions for transmitting a second control message indicating a second group identifier for the packet, the second group identifier associated with a second quantity of feedback processes, a second retention duration, or any combination thereof and transmitting a second retransmission of the packet in accordance with the second control message.

[0034] Some examples of the method, apparatuses, and non-transitory computer- readable medium described herein may further include operations, features, means, or instructions for receiving, in response to the control message, an acknowledgement for the first feedback process based on the first wireless device storing first decoding information for the packet.

[0035] A method for wireless communications at a first wireless device is described. The method may include transmitting, to a second wireless device, an indication of a capability of the first wireless device, the capability including a threshold quantity of code blocks per transport block within a duration of time, receiving a control message scheduling a transmission of a packet based on transmitting the indication, and communicating the scheduled transmission of the packet based on receiving the control message, the scheduled transmission including a quantity of code blocks that satisfies the threshold quantity of code blocks.

[0036] An apparatus for wireless communications at a first wireless device is described. The apparatus may include a processor, memory coupled with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to transmit, to a second wireless device, an indication of a capability of the first wireless device, the capability including a threshold quantity of code blocks per transport block within a duration of time, receive a control message scheduling a transmission of a packet based on transmitting the indication, and communicate the scheduled transmission of the packet based on receiving the control message, the scheduled transmission including a quantity of code blocks that satisfies the threshold quantity of code blocks.

[0037] Another apparatus for wireless communications at a first wireless device is described. The apparatus may include means for transmitting, to a second wireless device, an indication of a capability of the first wireless device, the capability including a threshold quantity of code blocks per transport block within a duration of time, means for receiving a control message scheduling a transmission of a packet based on transmitting the indication, and means for communicating the scheduled transmission of the packet based on receiving the control message, the scheduled transmission including a quantity of code blocks that satisfies the threshold quantity of code blocks.

[0038] A non-transitory computer-readable medium storing code for wireless communications at a first wireless device is described. The code may include instructions executable by a processor to transmit, to a second wireless device, an indication of a capability of the first wireless device, the capability including a threshold quantity of code blocks per transport block within a duration of time, receive a control message scheduling a transmission of a packet based on transmitting the indication, and communicate the scheduled transmission of the packet based on receiving the control message, the scheduled transmission including a quantity of code blocks that satisfies the threshold quantity of code blocks.

[0039] Some examples of the method, apparatuses, and non-transitory computer- readable medium described herein may further include operations, features, means, or instructions for transmitting a second indication of a capability of the first wireless device to communicate a fixed transport block size or a variable transport block size.

[0040] Some examples of the method, apparatuses, and non-transitory computer- readable medium described herein may further include operations, features, means, or instructions for transmitting a second indication including a second threshold quantity of code blocks per transport block with the duration of time based on other communications in a network, a battery level of the first wireless device, one or more energy harvesting parameters, or any combination thereof.

[0041] A method for wireless communications at a second wireless device is described. The method may include receiving, from a first wireless device, an indication of a capability of the first wireless device, the capability including a threshold quantity of code blocks per transport block within a duration of time, transmitting a control message scheduling a transmission of a packet based on receiving the indication, and communicating the scheduled transmission of the packet based on transmitting the control message, the scheduled transmission including a quantity of code blocks that satisfies the threshold quantity of code blocks.

[0042] An apparatus for wireless communications at a second wireless device is described. The apparatus may include a processor, memory coupled with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to receive, from a first wireless device, an indication of a capability of the first wireless device, the capability including a threshold quantity of code blocks per transport block within a duration of time, transmit a control message scheduling a transmission of a packet based on receiving the indication, and communicate the scheduled transmission of the packet based on transmitting the control message, the scheduled transmission including a quantity of code blocks that satisfies the threshold quantity of code blocks.

[0043] Another apparatus for wireless communications at a second wireless device is described. The apparatus may include means for receiving, from a first wireless device, an indication of a capability of the first wireless device, the capability including a threshold quantity of code blocks per transport block within a duration of time, means for transmitting a control message scheduling a transmission of a packet based on receiving the indication, and means for communicating the scheduled transmission of the packet based on transmitting the control message, the scheduled transmission including a quantity of code blocks that satisfies the threshold quantity of code blocks.

[0044] A non-transitory computer-readable medium storing code for wireless communications at a second wireless device is described. The code may include instructions executable by a processor to receive, from a first wireless device, an indication of a capability of the first wireless device, the capability including a threshold quantity of code blocks per transport block within a duration of time, transmit a control message scheduling a transmission of a packet based on receiving the indication, and communicate the scheduled transmission of the packet based on transmitting the control message, the scheduled transmission including a quantity of code blocks that satisfies the threshold quantity of code blocks.

[0045] Some examples of the method, apparatuses, and non-transitory computer- readable medium described herein may further include operations, features, means, or instructions for receiving a second indication of a capability of the first wireless device to communicate a fixed transport block size or a variable transport block size.

[0046] Some examples of the method, apparatuses, and non-transitory computer- readable medium described herein may further include operations, features, means, or instructions for receiving a second indication including a second threshold quantity of code blocks per transport block with the duration of time based on other communications in a network, a battery level of the first wireless device, one or more energy harvesting parameters, or any combination thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

[0047] FIG. 1 illustrates an example of a wireless communications system that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure.

[0048] FIG. 2 illustrates an example of a wireless communication system that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure.

[0049] FIG. 3 illustrates an example of a feedback process timeline that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure.

[0050] FIG. 4 illustrates an example of a resource configuration that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure.

[0051] FIG. 5 illustrates an example of a process flow that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure. [0052] FIGs. 6 and 7 show diagrams of devices that support hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure.

[0053] FIG. 8 shows a diagram of a communications manager that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure.

[0054] FIG. 9 shows a diagram of a system including a device that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure.

[0055] FIGs. 10 and 11 show diagrams of devices that support hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure.

[0056] FIG. 12 shows a diagram of a communications manager that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure.

[0057] FIG. 13 shows a diagram of a system including a device that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure.

[0058] FIGs. 14 through 17 show flowcharts illustrating methods that support hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure.

DETAILED DESCRIPTION

[0059] Some wireless communications systems may support wireless devices (e.g., user equipments (UEs), internet of things (loT) devices, and the like) with relatively limited capabilities (e.g., computational or hardware limited devices). For example, such devices may be unable to support a relatively high quantity of feedback processes (e.g., hybrid automatic repeat request acknowledgement (HARQ-ACK) processes), a relatively long time that the device can store a packet and/or decoding information for the packet (e.g., loglikelihood-ratios (LLRs) for one or more packets), or both. As an illustrative example, a first device may receive one or more packets via a transmission from a second device (e.g., a UE, an loT device, a base station, and the like) and attempt to decode the one or more packets. The first device may transmit feedback to the second device to indicate whether the first device successfully decoded the transmission. If the first device successfully decodes the packet, the first device may transmit a positive acknowledgement (ACK) as feedback. If the first device fails to successfully receive and/or decode the transmission, the first device may transmit a negative acknowledgement (NACK) as feedback.

[0060] In some examples, the first device may store decoding information (e.g., LLRs in a buffer) for the transmission, for example, to aid in decoding of future retransmissions of the packet. The second device may send a retransmission of the packet based on the corresponding decoding information stored at the first device. For example, the second device may transmit one or more redundancy versions (RVs). In some redundancy versions, the retransmission may be self-decodable (e.g., the retransmission of the packet may include all or most of the data), which may result in a relatively high reliability or likelihood of successful reception of the packet. Additionally or alternatively, in some redundancy versions the retransmission may be non-self-decodable (e.g., the retransmission of the packet may include portions of the data that the first device may combine decoding information with buffered decoding information to obtain the full packet), which may result in reduced signaling overhead. However, in some cases, the first device may drop or flush decoding information (e.g., due to low memory, relatively higher priority data communications, limited battery, etc.) prior to retransmission of the packet and the second device may be unaware of such flushing. In such cases, the first device may unsuccessfully decode the retransmission of the packet, which may result in extraneous retransmissions and poor communications efficiency.

[0061] In accordance with the techniques described herein, a first wireless device may indicate one or more capabilities (e.g., a retention duration for decoding information, a quantity of feedback processes supported for the duration, and the like) or other information associated with feedback processes (e.g., HARQ-ACK processes for which decoding information has been dropped) to a second wireless device, which may enable the second wireless device to account for such capabilities and/or information and result in improved communications reliability, efficiency, or both.

[0062] As an illustrative example, a first device may transmit control signaling including an indication of a quantity of feedback processes, a retention duration associated with the quantity of feedback processes, or both to a second wireless device. The second device may transmit a packet to the first device which the first device unsuccessfully receives or decodes. The first device may store decoding information for the failed transmission and transmit feedback to the second device indicating the failed transmission. In some cases, the second device may determine that a retention duration for the feedback process associated with the packet (e.g., the duration for which the first device stores decoding information for the packet) has expired. In such cases, the second device may transmit a retransmission of the packet using a self-decodable redundancy version (e.g., based on the second device determining that the first device has dropped the decoding information based on the expiration of the retention duration). Additionally or alternatively, the second device may determine that the retention duration has not expired. In such examples, the second device may transmit a retransmission of the packet based on the decoding information being stored in a buffer of the first device (e.g., a retransmission with a non-self-decodable redundancy version).

[0063] In some cases, the first device may drop decoding information prior to expiration of a retention duration associated with a feedback process for the one or more packets. The first device may transmit an indication of the dropped decoding information to a second device. Additionally or alternatively, the second device may transmit a message to a first device requesting a report of feedback processes for which the first device is storing respective decoding information. The second device may transmit a retransmission of a packet based on whether the first device is storing decoding information corresponding to the retransmission (e.g., if the second device receives an indication or a report that decoding information for the packet has been dropped, the second device may send a packet with a self-decodable redundancy version). In some examples, the first device may transmit an indication of a capability to support a threshold quantity of code blocks per transport block within a duration of time (e.g., a capability to process the threshold quantity of code blocks). The second device may schedule communications based on the indicated capability. The techniques described herein may improve communications efficiency and/or reliability of the system, improve battery life or other performance metrics at the devices, or any combination thereof.

[0064] Aspects of the disclosure are initially described in the context of wireless communications systems. Aspects of the disclosure are then described in the context of timelines, resource configurations, and process flows. Aspects of the disclosure are further illustrated by and described with reference to apparatus diagrams, system diagrams, and flowcharts that relate to hybrid automatic repeat request feedback techniques for wireless communications systems.

[0065] FIG. 1 illustrates an example of a wireless communications system 100 that supports hybrid automatic repeat request feedback techniques for wireless communications systems 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 communications, low latency communications, communications with low-cost and low-complexity devices, or any combination thereof.

[0066] 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.

[0067] 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.

[0068] 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 SI, 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.

[0069] 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.

[0070] 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 (loT) device, an Internet of Everything (loE) 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.

[0071] 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.

[0072] 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.

[0073] 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. [0074] 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 = /( f_max ’

seconds, where ^f_max may represent the maximum supported subcarrier spacing, and Nf 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).

[0075] 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., Nf) sampling periods. The duration of a symbol period may depend on the subcarrier spacing or frequency band of operation.

[0076] 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)).

[0077] 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.

[0078] 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.

[0079] Some UEs 115, such as MTC or loT 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.

[0080] Some UEs 115 may be configured to employ operating modes that reduce power consumption, such as half-duplex communications (e.g., a mode that supports one-way communication via transmission or reception, but not transmission and reception simultaneously). In some examples, half-duplex communications may be performed at a reduced peak rate. Other power conservation techniques for the UEs 115 include entering a power saving deep sleep mode when not engaging in active communications, operating over a limited bandwidth (e.g., according to narrowband communications), or a combination of these techniques. For example, some UEs 115 may be configured for operation using a narrowband protocol type that is associated with a defined portion or range (e.g., set of subcarriers or resource blocks (RBs)) within a carrier, within a guard-band of a carrier, or outside of a carrier.

[0081] 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). The UEs 115 may be designed to support ultra-reliable, low-latency, or critical functions. Ultra-reliable communications may include private communication or group communication and may be supported by one or more services such as push-to-talk, video, or data. Support for ultra-reliable, low-latency functions may include prioritization of services, and such services may be used for public safety or general commercial applications. The terms ultra-reliable, low-latency, and ultra-reliable low-latency may be used interchangeably herein.

[0082] 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.

[0083] In some systems, the D2D communication link 135 may be an example of a communication channel, such as a sidelink communication channel, between vehicles (e.g., UEs 115). In some examples, vehicles may communicate using vehicle-to- everything (V2X) communications, vehicle-to-vehicle (V2V) communications, or some combination of these. A vehicle may signal information related to traffic conditions, signal scheduling, weather, safety, emergencies, or any other information relevant to a V2X system. In some examples, vehicles in a V2X system may communicate with roadside infrastructure, such as roadside units, or with the network via one or more network nodes (e.g., base stations 105) using vehicle-to-network (V2N) communications, or with both.

[0084] 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 IP services 150 for one or more network operators. The IP services 150 may include access to the Internet, Intranet(s), an IP Multimedia Subsystem (IMS), or a Packet-Switched Streaming Service. [0085] 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).

[0086] 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.

[0087] 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.

[0088] 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.

[0089] 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.

[0090] 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.

[0091] 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).

[0092] 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.

[0093] 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.

[0094] The wireless communications system 100 may support feedback techniques as described herein. For example, various devices (e.g., UEs 115, base stations 105, etc.) may communicate or otherwise be configured with capability information associated with feedback processes, processing thresholds, or a combination thereof. For example, a first device may transmit, to a second device, control signaling indicating a capability to support a quantity of feedback processes and a retention duration associated with the feedback processes, groups of feedback processes (e.g., a first group corresponding to a first quantity of processes and a first retention duration, a second group corresponding to a second quantity of processes and a second retention duration, etc.). The second device may communicate based on the control signaling. For example, the second device may transmit self-decodable or non-self-decodable retransmissions of packets based on whether the retention duration for the packet (e.g., the retention duration for a feedback process group corresponding to the packet) has expired. Additionally or alternatively, the first device may transmit an indication of a threshold quantity of code blocks per transport block within a duration of time that is supported at the first device. The second device may account for the threshold quantity when scheduling communications with the first device. Such techniques may improve communications efficiency and/or reliability of the system, improve battery life or other performance metrics at the devices, or any combination thereof.

[0095] FIG. 2 illustrates an example of a wireless communication system 200 that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure. For example, the wireless communications system 200 may include UE 115-a and base station 105-a, which may be examples of a UE 115 or a base station 105 and may communicate with one another as described above with reference to FIG. 1. Although described as communications between a UE 115 and a base station 105, any type or quantity of devices may implement the techniques described herein (e.g., multiple UEs 115, loT devices, base stations 105, or any combination thereof, among other examples of wireless devices).

[0096] The base station 105-a may transmit downlink communications 205 to the UE 115-a via a communication link as described with reference to FIG. 1. Additionally or alternatively, the UE 115-a may transmit uplink communications 210 to the base station 105-a, though it is to be understood other communications and devices may be used (e.g., sidelink communications). For example, UE 115-a may communicate a data transmission 215 with the base station 105-a. The data transmission 215 may include one or more data packets.

[0097] As an illustrative example, base station 105-a may transmit data transmission 215 to UE 115-a. In some cases, UE 115-a may successfully receive and decode data transmission 215 and may transmit feedback message 220 to base station 105-a indicating the successful transmission (e.g., the feedback message 220 may include an ACK for one or more packets of the data transmission 215). In some other cases, UE 115-a may fail to successfully receive or decode data transmission 215 and may transmit feedback message 220 to base station 105-a indicating the failed transmission (e.g., the feedback message 220 may include a NACK for one or more packets of the data transmission 215). In such cases, UE 115-a may store decoding information for data transmission 215 in a buffer to aid in receiving and decoding future retransmissions of the packet. For example, base station 105-a may transmit retransmission 225, which may be a retransmission of one or more data packets of data transmission 215, to UE 115-a. UE 115-a may use the stored decoding information to successfully decode the one or more packets in combination with the retransmission 225. For example, UE 115-a may combine decoding information obtained from a previous transmission (e.g., data transmission 215 or an earlier retransmission 225) with decoding information of the retransmission 225. As an illustrative example, UE 115-a may combine an LLR of a currently received packet with an LLR of a previously received packet stored in a buffer, and use the combination to identify the correct data in the packet, although other examples of decoding information (e.g., parity bits or other error correction information) may be used for the techniques described herein.

[0098] However, in some cases, UE 115-a may drop or flush decoding information from the buffer for a failed packet transmission prior to a retransmission 225 of the packet (e.g., due to low memory, relatively higher priority data communications, limited battery, etc.) and base station 105-a may be unaware of such flushing. For example, bases station 105-a may transmit data transmission 215 to UE 115-a which UE 115-a unsuccessfully receives or decodes. Base station 105-a may receive feedback message 220 indicating a NACK and transmit retransmission 225, which may be a retransmission of data transmission 215, to UE 115-a. However, base station 105-a may use a non-self-decodable redundancy version (e.g., to reduce signaling overhead) which may result in UE 115-a failing to decode the transmission due to flushing the decoding information.

[0099] In some examples, UE 115-a may transmit an indication of one or more capabilities of the UE 115-a. For example, UE 115-a may transmit control signaling 230 indicating a retention duration associated with a group of feedback processes that is supported UE 115-a, a quantity of processes supported for the group of feedback processes, or any combination thereof. In some examples, UE 115-a may indicate multiple groups of processes (e.g., with respective quantities and retention durations). The retention duration may be a duration of time for which UE 115-a stores decoding information for packets assigned or otherwise belonging to a respective group of feedback processes. In some examples, the retention duration may be referred to as an expiry time, an expiry timer, an expiry timer duration, and the like. For example, UE 115-a may support a quantity of feedback processes (e.g., HARQ-ACK processes) as well as a retention duration corresponding to a time period during which the UE 115-a stores decoding information of received packet data for the quantity of feedback processes (e.g., how long a wireless device is able to store a set of LLRs or the expiry time of circular buffer) as described further with reference to FIG. 3.

[0100] UE 115-a may transmit control signaling 230 to base station 105-a indicating a quantity of feedback processes it supports and a retention duration associated with the processes. In some examples, base station 105-a may transmit control signaling configuring the UE 115-a with one or more groups of processes based on the control signaling. Base station 105-a may configure UE 115-a with one or more groups of feedback processes that satisfy one or more thresholds indicated by the capabilities of UE 115-a. For example, base station 105-a may assign, for a group of processes, a quantity that is less than or equal to the quantity of feedback processes indicated by control signaling 230, a retention duration that is less than or equal to the retention duration indicated by control signaling 230, or both. In some examples, base station 105-a may indicate HARQ identifiers (IDs) to indicate and/or update the processes that will be used under each group. For example, base station 105-a may include a HARQ- ID 1 to indicate group 1 (corresponding to a respective expiry time and/or quantity of processes) for a feedback process (e.g., a data transmission 215 and one or more retransmissions 225 of the data transmission 215). Control signaling 230 or other control signals or messages described herein may include, but are not limited to, RRC, MAC-CE, downlink control information (DCI), or other examples of control signaling.

[0101] As an illustrative example, base station 105-a may transmit data transmission 215 to UE 115-a which UE 115-a may unsuccessfully receive or decode. UE 115-a may store decoding information for data transmission 215 in a buffer and may transmit feedback message 220 to base station 105-a indicating the failed transmission. Base station 105-a may transmit control message 235 to UE 115-a scheduling retransmission 225, which may be a retransmission of data transmission 215, based on the information included in control signaling 230. Base station 105-a may transmit retransmission 225 to UE 115-a which UE 115-a may successfully decode upon reception. In some cases, base station 105-a may transmit retransmission 225 within the time period defined by the retention duration associated with feedback process corresponding to data transmission 215 (e.g., transmit with a redundancy version (RV) indicating the retransmission 225 includes non-self-decodable data). In some other cases, base station 105-a may transmit retransmission 225 outside the time period defined by the retention duration associated with feedback process corresponding to data transmission 215 (e.g., transmit with a RV indicating the retransmission 225 includes self-decodable data). Self-decodable data may refer to data packets that are decodable in a single transmission, while non-self-decodable data may refer to data packets that are not decodable in a single transmission (e.g., multiple transmissions may carry different data of the data packet).

[0102] In some cases, UE 115-a may transmit an indication of dropped decoding information (e.g., dropped circular buffer) prior to expiration of the retention duration associated with the information. For example, the UE 115-a may have limited resources to store decoding information (e.g., due to low memory, more important data arriving, or battery considerations) and may drop decoding information for a transmission from base station 105-a prior to expiration of the retention duration associated with the information. Stated alternatively, the UE 115-a may determine to drop a packet LLR based on low memory availability, more important data arriving at the UE 115-a, and the like, such that combining the stored packet LLR with an LLR generated from a retransmission is no longer possible because the stored packet LLR has been flushed. Thus, in some such examples, the UE 115-a may send an indication of the dropped decoding information (e.g., one or more LLRs for one or more packets have been dropped) to the base station 105-a such that the base station 105-a may retransmit the packet in a manner that is decodable by UE 115-a without the stored decoding information (e.g., transmit a retransmission with a self-decodable RV).

[0103] In some examples, a time offset between receiving a transmission and transmitting an indication of dropped decoding information may be signaled in control signaling such as RRC. For example, base station 105-a may configure UE 115-a with the time offset via RRC. In such examples, UE 115-a may report dropped or flushed decoding information for a respective packet at the time indicated by the time offset (e.g., the time between receiving the transmission and transmitting the indication of the dropped decoding information). Additionally or alternatively, UE 115-a may be configured with uplink resources (e.g., a physical uplink control channel (PUCCH) occasion, dedicated periodic or semi-persistent uplink occasions, and the like, or sidelink resources for sidelink communications) for such reporting. In some examples, the resources for reporting may be configured via control signaling (e.g., the occasions or resources may be configured in RRC/MAC-CE jointly with DCI). Therefore, base station 105-a may transmit retransmission 225, which may be a retransmission of data transmission 215, to UE 115-a based on the indication in control signaling 230. For example, the base station 105-a may transmit a non-self-decodable retransmission 225 based on receiving the indication.

[0104] In some cases, UE 115-a may transmit the indication of decoding data that is dropped or flushed before an expiration of a respective retention duration via control signaling. For example, UE 115-a may send such an indication as channel state information (CSI) with HARQ-ACK PUCCH, or in a separate PUCCH occasion (e.g., dedicated periodic/semi-persistent uplink occasions for such reporting configured as described above). Additionally or alternatively to reporting packets associated with dropped circular buffers, UE 115-a may report whether it will keep or flush a packet. For example, in the CSI with HARQ-ACK PUCCH, UE 115-a may indicate an ACK if it is able to maintain the buffer for a packet or a NACK if it has or plans to drop the buffer.

[0105] In some examples, the wireless communications system 200 may support communications for high frequency ranges (e.g., FR2 or beyond FR2 high frequency) and the techniques described herein may resolve or mitigate issues involved with low capability devices being unable to process a relatively high quantity of slots occurring within a short duration (e.g., a few ms), which may result in difficulties at such devices in keeping HARQ buffering, performing combining, or both.

[0106] In some examples, base station 105-a may transmit a message to UE 115-a requesting what feedback processes for which UE 115-a is storing respective decoding information (e.g., for which feedback processes the UE 115-a is preserving LLR buffer(s) corresponding to one or more negatively acknowledged transport blocks, code blocks, code block groups, or any combination thereol). For example, base station 105-a may receive feedback indicating a failed transmission (e.g., a NACK message) for one or more feedback processes supported by the UE 115-a. Base station 105-a may transmit a message to the UE 115-a requesting a report on one or more feedback processes for which the UE 115-a is storing decoding information for one or more packets the UE 115-a was unable to decode. The UE 115-a may respond with an indication of the one or more feedback processes to the base station 105-a. For example, base station 105-a may transmit control message 235 to UE 115-a requesting a report on feedback processes for which the first device is storing decoding information. UE 115-a may respond with control signaling 230 indicating the one or more feedback processes corresponding to failed transmissions for which the first device is storing decoding information to the second device. In some cases, the request may be sent in a DCI message and the first wireless device may respond in PUCCH or physical uplink shared channel (PUSCH). In some cases (e.g., sidelink), the request may be transmitted in sidelink control information (SCI) and the response may be transmitted in a PSFCH, MAC-CE, or a dedicated PSSCH, for example, in sidelink communications between devices (e.g., base station 105-a may be an example of another UE 115). For example, the base station 105-a may send a request in a DCI, and the UE 11-5 may respond in a PUCCH, PUSCH, PSFCH, MAC-CE, a dedicated PSSCH, with the one or more HARQ-ACK IDs, among those LLR buffers that are known to be stored, that are still unflushed.

[0107] Additionally or alternatively, UE 115-a may receive a message (e.g., DCI) from base station 105-a indicating scheduling of a retransmission and may respond with feedback (e.g., ACK/NACK) based on whether the UE 115-a is storing decoding information for the retransmission. If the UE 115-a is storing decoding information for the transmission (e.g., includes one or more LLRs in a circular buffer), it may transmit a positive feedback message (e.g., ACK) to the base station 105-a. If the UE 115-a is not storing decoding information for the retransmission, it may respond with a negative feedback message (e.g., NACK) or may remain silent. As an example, if the base station 105-a receives a negative feedback message or no response, it may transmit the retransmission such that the UE 115-a may not use or store the decoding information (e.g., a self-decodable RV, such as RV 0 or 3).

[0108] For example, base station 105-a may transmit control message 235 to UE 115-a scheduling retransmission 225, which may be a retransmission of data transmission 215. In some cases, UE 115-a may be storing decoding information for data transmission 215 and may transmit control signaling 230 to base station 105-a containing positive feedback. In response, base station 105-a may transmit retransmission 225 including packets that may be decoded using decoding information for data transmission 215 (e.g., a non-self-decodable retransmission). UE 115-a may receive and decode retransmission 225 using stored decoding information for data transmission 215. In some other cases, UE 115-a may not be storing decoding information for data transmission 215 and may transmit control signaling 230 to base station 105-a containing negative feedback. In response, base station 105-a may transmit retransmission 225 including packets that may be decoded without using decoding information for data transmission 215 (e.g., a self-decodable retransmission). UE 115-a may receive and decode retransmission 225.

[0109] In some examples, UE 115-a may transmit an indication of a threshold quantity of code blocks per transport block that the UE is capable of supporting within a duration of time, as further described with reference to FIG. 4. For example, UE 115-a may transmit control signaling 230 to base station 105-a indicating a threshold quantity of code blocks per transport block that the UE is capable of supporting within a duration of time. Base station 105-a may transmit data transmission 215 to UE 115-a in accordance with the threshold quantity indicated in control signaling 230. In some cases, UE 115-a may transmit a second indication of a capability to communicate a fixed transport block size or a variable transport block size. Additionally or alternatively, UE 115-a may transmit a second indication of a second threshold quantity code blocks per transport block within the duration of time based on other communications in a network, a battery level of UE 115-a, one or more energy harvesting parameters, or any combination thereof.

[0110] The techniques described herein may be applied in a sidelink scenario. In some such cases, DCI communications may be sidelink control information (SCI) communications, PUSCH communications may be physical sidelink shared channel (PSSCH) communications, and Uu RRC or MAC-CE communications may be PC5 RRC or MAC-CE communications. Additionally or alternatively, PUCCH communications may be physical feedback shared channel (PSFCH) communications, a MAC-CE, or a dedicated PSSCH to carry feedback information from one wireless device (e.g. UE 115-a) to another device).

[0111] FIG. 3 illustrates an example of a feedback process timeline 300 that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure. For example, feedback process timeline 300 may depict the timeline associated with the storage of decoding information at UE 115 -a.

[0112] In some cases, a first device may transmit, to a second device, an indication of a quantity of feedback processes and a retention duration associated with the processes for consideration during future transmissions, as previously described with respects to FIG. 2. Stated alternatively, a device may indicate how many feedback processes it can support as well as for how long it is able to store a set of LLRs (or other decoding information buffered for combining with retransmissions) which may be referred to as a retention duration (e.g., an expiry time of a circular buffer). Such techniques may be generalized into subsets or groups of feedback processes where each subset may have a respective expiry time (e.g., retention duration).

[0113] As an illustrative example of two groups with respective quantities of processes and retention durations, a first device may signal to a second device that it may maintain decoding information (e.g., a circular buffer) of a quantity of XI transmissions (e.g., HARQ-ACK processes) for a retention duration of T_X1 time slots for a first group, while it may maintain X2 transmissions (e.g., a second set of HARQ- ACK processes) for a retention duration of T_X2 time slots for a second group. As an illustrative example, the retention duration (e.g., T_X1 or T_X2) may be indicative of 2 time slots, which may mean the device stores decoding information for 2 time slots, after which the decoding information (e.g., LLRs) may be flushed. In some cases, the retention duration may be indicative of infinity, which may mean the device stores and combines the decoding information for all versions of the feedback process (e.g., HARQ-ACK process) until a retransmission corresponding to the decoding information is received and successfully decoded (e.g., the device may maintain the decoding information indefinitely for retention durations that are infinity). In some other cases, the retention duration may indicate zero slots, which may mean the wireless device stores no decoding information beyond the current time slot, for example compared to a Y=2 indicating that the device may store decoding information for 2 slots after the current time slot, after which the buffer may be flushed. In some examples, each feedback process may be located or assigned to a set or group (e.g., a feedback process may be assigned to the group of XI or X2 processes). The retention duration may be a time span, time between transmissions, a total amount of code blocks, or a combination thereof, among other examples of time durations. In some examples, the devices may maintain a timer associated with the retention duration (e.g., a UE, base station, or other device may flush data based on expiration of the timer or transmit data with a different RV based on expiration of the timer).

[0114] In some cases, a second device may configure the first device with the groups of feedback processes (e.g., 1, 2, 3 groups or more based on device preference) and for each group, a retention duration, respecting the limitations indicated by the first device. For example, a second wireless device may configure groups (e.g., XI and X2) and retention durations (e.g., T_X1 and T_X2) for a first wireless device (e.g., configured by RRC or MAC-CE signaling) and locate or assign each feedback process (e.g., HARQ-ACK process) to a group. The second wireless device may configure the groups such that XI transmissions satisfies (e.g., is less than or equal to) the quantity of transmissions supported by the first device for the respective retention duration (e.g., T_X1) and the X2 transmissions satisfies (e.g., is less than or equal to) the quantity of transmissions supported by the first device for the respective retention duration (e.g., T_X2).

[0115] In the illustrative example of timeline 325, a UE 115 may receive physical downlink shared channel (PDSCH) 305 belonging to a first group (e.g., XI) and may store decoding information for PDSCH 305 for retention duration 315 (e.g., T_X1). At 330, retention duration 315 may expire and the UE 115 may drop the decoding information for PDSCH 305. In some examples, as illustrated on timeline 335, a UE 115 may receive PDSCH 310 belonging to a second group (e.g., X2) and may store decoding information for PDSCH 310 for retention duration 320 (e.g., T_X2). At 340, retention duration 320 may expire and the UE 115 may drop the decoding information for PDSCH 310. As previously described with respects to FIG. 2, at 330 or 340 the UE 115 may transmit, to the base station, an indication of the dropped decoding information corresponding to PDSCH 305 or PDSCH 310 respectively. In some cases, PDSCH 305 and PDSCH 310 may be on the same or different component carriers (CCs) (e.g., XI and X2 may be on the same or different CCs).

[0116] In some cases, a second device may configure and/or change the groupings and retention durations for a first device (e.g., using RRC or MAC-CE). As an illustrative example, a UE 115 may indicate to a base station 105 a suggestion of a group 1 including XI feedback processes of timer T_X1, a group 2 including X2 feedback processes of timer T_X2, and a group 3 including X3 feedback processes of timer T_X3. The base station 105 may configure the UE 115 with groups and retention durations respecting the limits of the suggestion indicated by the UE 115. For example, the UE 115 may indicate a suggestion of a group 1 including 1 feedback process of timer 2 slots, a group 2 including 4 feedback processed of timer 4 slots, and a group 3 including 3 feedback processes of timer 8 slots. The base station 105 may configure UE 115 such that group 1 includes 1 feedback process of timer 1 slot (e.g., less than the suggested 2 slots), group 2 includes 4 feedback processes of timer 3 slots (e.g., less than the suggested 4 slots), and group 3 includes 3 feedback processes of timer 8 slots (e.g., equal to the selected 8 slots), though these are illustrative examples and any quantity of groups, slots, and processes may be used.

[0117] In some examples, a second device may indicate or update the feedback processes that may be used under each group (e.g., using RRC or MAC-CE). For example, a base station 105 may indicate to a UE 115 that HARQ-ID 1 is under a group 1, HARQ-ID 2, 3, 4, and 5 are under a group 2, and HARQ-ID 6, 7, 8 are under a group 3 (e.g., or any combination of HARQ processes). In some examples, the base station 105 may change the groups, the expiry times, or both, using control signaling such as RRC or MAC-CE.

[0118] In some examples, a second device may indicate to a first device the HARQ ID of each transmission and may change the group of the current transmission (e.g., instead of configuring groups in RRC or MAC-CE) via dynamic configuration. For example, a second device may indicate to a first device the group of which the current transmission belongs to (e.g., which group the HARQ-ID belongs to) and the first device may determine the retention duration of the current transmission (e.g., current HARQ-ID) based on the HARQ ID. As an illustrative example, a UE 115 may be configured such that a HARQ-ID 1 is under a group 1 with a retention duration of 2 slots. A base station 105 may indicate that a current transmission has a HARQ-ID of 1 and a UE 115 may identify that the transmission belongs to group 1 and has a retention duration of 2 slots (e.g., UE 115 may maintain a buffer of decoding information for the transmission for 2 slots). Later, the base station 105 may indicate that a retransmission with a HARQ-ID of 1 belongs to group 2 (e.g., via downlink DCI or other control signaling) and UE 115 may use the retention duration of group 2 based on the indication. Such techniques may enable dynamic configuration of groups for various feedback processes.

[0119] FIG. 4 illustrates an example of a resource configuration 400 that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure. For example, resource configuration 400 may indicate a quantity of code block groups (CBGs) 410 in a transport block (TB) 405 as well as a quantity of code blocks (CBs) 415 in a CBG 410.

[0120] In some cases, a first device may transmit an indication of a capability of the first device to process a threshold quantity of CBs per TB within a duration of time to a second device (e.g., 100 CBs within 100 ms). For example, a first wireless device may have a limited capability to process certain TB sizes or CB sizes with a certain period of time or may have a limited capability to process a certain number of CBs or CBGs in a single transmission. As an illustrative example, a UE 115 may indicate to a base station 105 (e.g., RRC indicated using user assisted information (UAI)) that in a indicated period of time, the UE 115 is capable of processing a quantity of CBGs in TB 405, such as CBG 410-a and CBG 410-b. In some examples, the UE 115 may indicate to a base station 105 that it is capable of processing a specific quantity of CBs in CBG 410, such as CB 415-a, CB 415-b, CB 415-c, and CB 415-d. Additionally or alternatively, a first device may indicate that it is capable of managing fixed transport block sizes (TBSs) or variable TBSs to a second device.

[0121] Additionally or alternatively, a first device may indicate to a second device a change in the period of time corresponding to the processing capability. For example, a UE 115 may indicate to a base station 105 a change in time period or a different time period based on engagement in other tasks in the network (e.g., sidelink or Uu link) or based on battery level (e.g., low battery level or access to energy harvesting sources such as solar, vibration, radio frequency (RF) energy harvesting, and the like).

[0122] FIG. 5 illustrates an example of a process flow 500 that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure. Process flow 500 may be performed by UE 115-b and base station 105-b, which may be examples of UE 115 and base station 105 described above with references to FIGs. 1-2. Additionally or alternatively, the process flow 500 may be performed by any quantity or type of devices (e.g., the process flow 500 may illustrate sidelink communications between multiple UEs 115 or base stations 105). In some examples, UE 115-b may transmit an indication of a capability to base station 105-b to support HARQ feedback processes.

[0123] In some cases, at 505, UE 115-b may transmit, to base station 105-b, an indication of a capability of UE 115-b. The capability may indicate a threshold quantity of code blocks per transport block within a duration of time.

[0124] In some examples, at 510, UE 115-b may receive control signaling indicating resources associated with reporting that UE 115-b has dropped decoding information.

[0125] At 515, UE 115-b may transmit, to base station 105-b, control signaling indicating a quantity of feedback processes supported by UE 115-b and a retention duration associated with the quantity of feedback processes. The retention duration may correspond to a time period (e.g., a time span, time between transmissions, a total amount of code blocks, or the like thereof) that UE 115-b stores decoding information of received packet data for a feedback process. In some examples, the control signaling may indicate multiple groups including a first group of feedback processes and a second group of feedback processes, each group corresponding to a respective retention duration.

[0126] As an illustrative example, the control signaling may include an indication of a first group of feedback processes comprising the quantity of feedback processes, a second group of feedback processes, a first retention duration corresponding to the first group of feedback processes, and a second retention duration corresponding to the second group of feedback processes, which may be examples of groups and durations as described with reference to FIGs. 1-4. The first retention duration may include a first quantity of slots during which UE 115-b stores decoding information for the first group of feedback processes. The second retention duration may include a second quantity of slots during which UE 115-b stores decoding information for the second group of feedback processes. [0127] In some cases, at 520, base station 105-b may transmit a control message scheduling a packet transmission based on the capability indication received from UE 115-b at 505.

[0128] At 525, base station 105-b may transmit a packet transmission to UE 115-b. In some cases, the packet transmission may be based on the control message transmitted at 520. In some examples, the packet transmission may include a quantity of code blocks that satisfies the threshold quantity of code blocks indicated in the capability indication transmitted at 505. Additionally or alternatively, UE 115-b may receive the packet associated with the first feedback process based on the first feedback process being assigned to a first group of feedback processes including the quantity of feedback processes.

[0129] In some cases, UE 115-b may successfully receive and decode the packet transmission and, at 530, may transmit a positive feedback message (ACK). In some other cases, UE 115-b may unsuccessfully receive or decode the packet transmission and, at 530, may transmit a negative feedback message (e.g., NACK). If UE 115-b unsuccessfully receives or decodes the packet transmission it may store decoding information for the transmission to aid in the decoding of future retransmissions. The decoding information may include log likelihood ratio information for the packet.

[0130] At 535, base station 105-b may transmit a control message scheduling a retransmission of the packet transmitted at 525. The control message may be in accordance with the control signaling received at 515, indicating a quantity of feedback processes supported by UE 115-b and a retention duration associated with the quantity of feedback processes. In some examples, the control message may indicate a group identifier associated with the packet. The group identifier may correspond to the quantity of feedback processes and the retention duration. Additionally or alternatively, base station 105-b may transmit a second control message indicating a second group identified for the packet. The second group identified may be associated with a second quantity of feedback processes, a second retention duration, or both.

[0131] In some other cases, at 535, base station 105-b may transmit a control message requesting that UE 115-b report a subset of the feedback processes for which the first wireless device is storing respective decoding information. [0132] In some cases, at 540, UE 115-b may transmit, via the resources indicated by the control signaling received at 510, an indication that UE 115- has dropped decoding information prior to expiration of the retention duration. In some other cases, UE 115-b may transmit a report indicating the subset of feedback processes for which UE 115-b is storing decoding information, based on the request received at 535. For example, UE 115-b may transmit an acknowledgement for the first feedback process based on UE 115-b storing first decoding information for the packet.

[0133] At 545, base station 105-b may transmit a retransmission of the packet transmitted at 525. The retransmission may be based on the first control message transmitted at 535. Additionally or alternatively, the retransmission may be based on the second control message transmitted at 535. In some cases, the retransmission of the packet may include self-decodable data based on the retransmission packet being scheduled outside the time period defined by the retention duration. In some other cases, the retransmission of the packet may include non-self-decodable data based on the retransmission of the packet being scheduled within the time period defined by the retention duration.

[0134] In some cases, at 550, UE 115-b may transmit a second indication of a capability of UE 115-b to communicate a fixed transport block size of a variable transport block size. Additionally or alternatively, the capability indication may include a second threshold quantity of code blocks per transport block with the duration of time based on other communications in a network, a battery level of the first wireless device, one or more energy harvesting parameters, or any combination thereof.

[0135] FIG. 6 shows a diagram 600 of a device 605 that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure. The device 605 may be an example of aspects of a UE 115, a base station 105, or any wireless device as described herein. The device 605 may include a receiver 610, a transmitter 615, and a communications manager 620. The device 605 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

[0136] The receiver 610 may provide a means for receiving information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to hybrid automatic repeat request feedback techniques for wireless communications systems). Information may be passed on to other components of the device 605. The receiver 610 may utilize a single antenna or a set of multiple antennas.

[0137] The transmitter 615 may provide a means for transmitting signals generated by other components of the device 605. For example, the transmitter 615 may transmit information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to hybrid automatic repeat request feedback techniques for wireless communications systems). In some examples, the transmitter 615 may be colocated with a receiver 610 in a transceiver module. The transmitter 615 may utilize a single antenna or a set of multiple antennas.

[0138] The communications manager 620, the receiver 610, the transmitter 615, or various combinations thereof or various components thereof may be examples of means for performing various aspects of hybrid automatic repeat request feedback techniques for wireless communications systems as described herein. For example, the communications manager 620, the receiver 610, the transmitter 615, or various combinations or components thereof may support a method for performing one or more of the functions described herein.

[0139] In some examples, the communications manager 620, the receiver 610, the transmitter 615, or various combinations or components thereof may be implemented in hardware (e.g., in communications management circuitry). The hardware may include a processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic device, a discrete gate or transistor logic, discrete hardware components, or any combination thereof configured as or otherwise supporting a means for performing the functions described in the present disclosure. In some examples, a processor and memory coupled with the processor may be configured to perform one or more of the functions described herein (e.g., by executing, by the processor, instructions stored in the memory).

[0140] Additionally or alternatively, in some examples, the communications manager 620, the receiver 610, the transmitter 615, or various combinations or components thereof may be implemented in code (e.g., as communications management software or firmware) executed by a processor. If implemented in code executed by a processor, the functions of the communications manager 620, the receiver 610, the transmitter 615, or various combinations or components thereof may be performed by a general-purpose processor, a DSP, a central processing unit (CPU), an ASIC, an FPGA, or any combination of these or other programmable logic devices (e.g., configured as or otherwise supporting a means for performing the functions described in the present disclosure).

[0141] In some examples, the communications manager 620 may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using or otherwise in cooperation with the receiver 610, the transmitter 615, or both. For example, the communications manager 620 may receive information from the receiver 610, send information to the transmitter 615, or be integrated in combination with the receiver 610, the transmitter 615, or both to receive information, transmit information, or perform various other operations as described herein.

[0142] The communications manager 620 may support wireless communications at a first wireless device in accordance with examples as disclosed herein. For example, the communications manager 620 may be configured as or otherwise support a means for transmitting, to a second wireless device, control signaling indicating a quantity of feedback processes supported by the first wireless device and a retention duration associated with the quantity of feedback processes, where the retention duration corresponds to a time period during which the first wireless device stores decoding information of received packet data for a feedback process. The communications manager 620 may be configured as or otherwise support a means for transmitting a feedback message indicating unsuccessful decoding of a packet associated with a first feedback process of the quantity of feedback processes. The communications manager 620 may be configured as or otherwise support a means for receiving a control message scheduling a retransmission of the packet in accordance with the control signaling. The communications manager 620 may be configured as or otherwise support a means for receiving the retransmission of the packet based on the control message.

[0143] Additionally or alternatively, the communications manager 620 may support wireless communications at a first wireless device in accordance with examples as disclosed herein. For example, the communications manager 620 may be configured as or otherwise support a means for transmitting, to a second wireless device, an indication of a capability of the first wireless device, the capability including a threshold quantity of code blocks per transport block within a duration of time. The communications manager 620 may be configured as or otherwise support a means for receiving a control message scheduling a transmission of a packet based on transmitting the indication. The communications manager 620 may be configured as or otherwise support a means for communicating the scheduled transmission of the packet based on receiving the control message, the scheduled transmission including a quantity of code blocks that satisfies the threshold quantity of code blocks.

[0144] By including or configuring the communications manager 620 in accordance with examples as described herein, the device 605 (e.g., a processor controlling or otherwise coupled to the receiver 610, the transmitter 615, the communications manager 620, or a combination thereof) may support feedback techniques as described herein. For example, such techniques may enable the device 605 to indicate the capability of the device 605, indicate dropped packets for feedback processes, and the like as described herein, which may result in increased power efficiency of the device 605, improved reliability of communications, or both, among other advantages.

[0145] FIG. 7 shows a diagram 700 of a device 705 that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure. The device 705 may be an example of aspects of a device 605 a UE 115, a base station 105, or any wireless device as described herein. The device 705 may include a receiver 710, a transmitter 715, and a communications manager 720. The device 705 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

[0146] The receiver 710 may provide a means for receiving information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to hybrid automatic repeat request feedback techniques for wireless communications systems). Information may be passed on to other components of the device 705. The receiver 710 may utilize a single antenna or a set of multiple antennas. [0147] The transmiter 715 may provide a means for transmiting signals generated by other components of the device 705. For example, the transmiter 715 may transmit information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to hybrid automatic repeat request feedback techniques for wireless communications systems). In some examples, the transmiter 715 may be colocated with a receiver 710 in a transceiver module. The transmiter 715 may utilize a single antenna or a set of multiple antennas.

[0148] The device 705, or various components thereof, may be an example of means for performing various aspects of hybrid automatic repeat request feedback techniques for wireless communications systems as described herein. For example, the communications manager 720 may include a control signal component 725, a feedback component 730, a scheduling component 735, a packet component 740, a capability component 745, a communication component 750, or any combination thereof. The communications manager 720 may be an example of aspects of a communications manager 620 as described herein. In some examples, the communications manager 720, or various components thereof, may be configured to perform various operations (e.g., receiving, monitoring, transmiting) using or otherwise in cooperation with the receiver 710, the transmitter 715, or both. For example, the communications manager 720 may receive information from the receiver 710, send information to the transmiter 715, or be integrated in combination with the receiver 710, the transmiter 715, or both to receive information, transmit information, or perform various other operations as described herein.

[0149] The communications manager 720 may support wireless communications at a first wireless device in accordance with examples as disclosed herein. The control signal component 725 may be configured as or otherwise support a means for transmiting, to a second wireless device, control signaling indicating a quantity of feedback processes supported by the first wireless device and a retention duration associated with the quantity of feedback processes, where the retention duration corresponds to a time period during which the first wireless device stores decoding information of received packet data for a feedback process. The feedback component 730 may be configured as or otherwise support a means for transmiting a feedback message indicating unsuccessful decoding of a packet associated with a first feedback process of the quantity of feedback processes. The scheduling component 735 may be configured as or otherwise support a means for receiving a control message scheduling a retransmission of the packet in accordance with the control signaling. The packet component 740 may be configured as or otherwise support a means for receiving the retransmission of the packet based on the control message.

[0150] Additionally or alternatively, the communications manager 720 may support wireless communications at a first wireless device in accordance with examples as disclosed herein. The capability component 745 may be configured as or otherwise support a means for transmitting, to a second wireless device, an indication of a capability of the first wireless device, the capability including a threshold quantity of code blocks per transport block within a duration of time. The scheduling component 735 may be configured as or otherwise support a means for receiving a control message scheduling a transmission of a packet based on transmitting the indication. The communication component 750 may be configured as or otherwise support a means for communicating the scheduled transmission of the packet based on receiving the control message, the scheduled transmission including a quantity of code blocks that satisfies the threshold quantity of code blocks.

[0151] FIG. 8 shows a diagram 800 of a communications manager 820 that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure. The communications manager 820 may be an example of aspects of a communications manager 620, a communications manager 720, or both, as described herein. The communications manager 820, or various components thereof, may be an example of means for performing various aspects of hybrid automatic repeat request feedback techniques for wireless communications systems as described herein. For example, the communications manager 820 may include a control signal component 825, a feedback component 830, a scheduling component 835, a packet component 840, a capability component 845, a communication component 850, or any combination thereof. Each of these components may communicate, directly or indirectly, with one another (e.g., via one or more buses). [0152] The communications manager 820 may support wireless communications at a first wireless device in accordance with examples as disclosed herein. The control signal component 825 may be configured as or otherwise support a means for transmitting, to a second wireless device, control signaling indicating a quantity of feedback processes supported by the first wireless device and a retention duration associated with the quantity of feedback processes, where the retention duration corresponds to a time period during which the first wireless device stores decoding information of received packet data for a feedback process. The feedback component 830 may be configured as or otherwise support a means for transmitting a feedback message indicating unsuccessful decoding of a packet associated with a first feedback process of the quantity of feedback processes. The scheduling component 835 may be configured as or otherwise support a means for receiving a control message scheduling a retransmission of the packet in accordance with the control signaling. The packet component 840 may be configured as or otherwise support a means for receiving the retransmission of the packet based on the control message.

[0153] In some examples, to support receiving the control message, the scheduling component 835 may be configured as or otherwise support a means for receiving the control message scheduling the retransmission of the packet that includes self-decodable data based on the retransmission of the packet being scheduled outside the time period or non-self-decodable data based on the retransmission of the packet being scheduled within the time period.

[0154] In some examples, the decoding information includes log likelihood ratio information for the packet.

[0155] In some examples, the control signal component 825 may be configured as or otherwise support a means for receiving second control signaling indicating resources associated with reporting that the first wireless device has dropped the decoding information. In some examples, the feedback component 830 may be configured as or otherwise support a means for transmitting, via the indicated resources, an indication that the first wireless device has dropped the decoding information prior to an expiration of the retention duration. [0156] In some examples, the communication component 850 may be configured as or otherwise support a means for receiving a message requesting that the first wireless device report a subset of feedback processes of the quantity of feedback processes for which the first wireless device is storing respective decoding information. In some examples, the feedback component 830 may be configured as or otherwise support a means for transmitting an indication of the subset of feedback processes to the second wireless device.

[0157] In some examples, to support transmitting the control signaling, the control signal component 825 may be configured as or otherwise support a means for transmitting the control signaling indicating a first group of feedback processes including the quantity of feedback processes, a second group of feedback processes, the retention duration corresponding to the first group of feedback processes, and a second retention duration corresponding to the second group of feedback processes.

[0158] In some examples, the retention duration includes a first quantity of slots during which the first wireless device stores decoding information for the first group of feedback processes. In some examples, the second retention duration includes a second quantity of slots during which the first wireless device stores decoding information for the second group of feedback processes.

[0159] In some examples, the control signaling indicates a set of multiple groups including the first group and the second group, each group of the set of multiple groups corresponding to a respective retention duration.

[0160] In some examples, the packet component 840 may be configured as or otherwise support a means for receiving the packet associated with the first feedback process based on the first feedback process being assigned to a first group of feedback processes including the quantity of feedback processes.

[0161] In some examples, to support receiving the control message, the packet component 840 may be configured as or otherwise support a means for receiving the control message indicating a group identifier associated with the packet, the group identifier corresponding to the quantity of feedback processes and the retention duration. [0162] In some examples, the packet component 840 may be configured as or otherwise support a means for receiving a second control message indicating a second group identifier for the packet, the second group identifier associated with a second quantity of feedback processes, a second retention duration, or any combination thereof. In some examples, the packet component 840 may be configured as or otherwise support a means for receiving a second retransmission of the packet in accordance with the second control message.

[0163] In some examples, the feedback component 830 may be configured as or otherwise support a means for transmitting, in response to the control message, an acknowledgement for the first feedback process based on the first wireless device storing first decoding information for the packet.

[0164] Additionally or alternatively, the communications manager 820 may support wireless communications at a first wireless device in accordance with examples as disclosed herein. The capability component 845 may be configured as or otherwise support a means for transmitting, to a second wireless device, an indication of a capability of the first wireless device, the capability including a threshold quantity of code blocks per transport block within a duration of time. In some examples, the scheduling component 835 may be configured as or otherwise support a means for receiving a control message scheduling a transmission of a packet based on transmitting the indication. The communication component 850 may be configured as or otherwise support a means for communicating the scheduled transmission of the packet based on receiving the control message, the scheduled transmission including a quantity of code blocks that satisfies the threshold quantity of code blocks.

[0165] In some examples, the capability component 845 may be configured as or otherwise support a means for transmitting a second indication of a capability of the first wireless device to communicate a fixed transport block size or a variable transport block size.

[0166] In some examples, the capability component 845 may be configured as or otherwise support a means for transmitting a second indication including a second threshold quantity of code blocks per transport block with the duration of time based on other communications in a network, a battery level of the first wireless device, one or more energy harvesting parameters, or any combination thereof.

[0167] FIG. 9 shows a diagram of a system 900 including a device 905 that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure. The device 905 may be an example of or include the components of a device 605, a device 705, a UE 115, a base station 105, or any wireless device as described herein. The device 905 may communicate wirelessly with one or more base stations 105, UEs 115, or any combination thereof. The device 905 may include components for bi-directional voice and data communications including components for transmitting and receiving communications, such as a communications manager 920, an input/output (I/O) controller 910, a transceiver 915, an antenna 925, a memory 930, code 935, and a processor 940. These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more buses (e.g., a bus 945).

[0168] The I/O controller 910 may manage input and output signals for the device 905. The I/O controller 910 may also manage peripherals not integrated into the device 905. In some cases, the I/O controller 910 may represent a physical connection or port to an external peripheral. In some cases, the I/O controller 910 may utilize an operating system such as iOS®, ANDROID®, MS-DOS®, MS-WINDOWS®, OS/2®, UNIX®, LINUX®, or another known operating system. Additionally or alternatively, the I/O controller 910 may represent or interact with a modem, a keyboard, a mouse, a touchscreen, or a similar device. In some cases, the I/O controller 910 may be implemented as part of a processor, such as the processor 940. In some cases, a user may interact with the device 905 via the I/O controller 910 or via hardware components controlled by the I/O controller 910.

[0169] In some cases, the device 905 may include a single antenna 925. However, in some other cases, the device 905 may have more than one antenna 925, which may be capable of concurrently transmitting or receiving multiple wireless transmissions. The transceiver 915 may communicate bi-directionally, via the one or more antennas 925, wired, or wireless links as described herein. For example, the transceiver 915 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. The transceiver 915 may also include a modem to modulate the packets, to provide the modulated packets to one or more antennas 925 for transmission, and to demodulate packets received from the one or more antennas 925. The transceiver 915, or the transceiver 915 and one or more antennas 925, may be an example of a transmitter 615, a transmitter 715, a receiver 610, a receiver 710, or any combination thereof or component thereof, as described herein.

[0170] The memory 930 may include random access memory (RAM) and read-only memory (ROM). The memory 930 may store computer-readable, computer-executable code 935 including instructions that, when executed by the processor 940, cause the device 905 to perform various functions described herein. The code 935 may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. In some cases, the code 935 may not be directly executable by the processor 940 but may cause a computer (e.g., when compiled and executed) to perform functions described herein. In some cases, the memory 930 may contain, among other things, a basic I/O system (BIOS) which may control basic hardware or software operation such as the interaction with peripheral components or devices.

[0171] The processor 940 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 940 may be configured to operate a memory array using a memory controller. In some other cases, a memory controller may be integrated into the processor 940. The processor 940 may be configured to execute computer-readable instructions stored in a memory (e.g., the memory 930) to cause the device 905 to perform various functions (e.g., functions or tasks supporting hybrid automatic repeat request feedback techniques for wireless communications systems). For example, the device 905 or a component of the device 905 may include a processor 940 and memory 930 coupled to the processor 940, the processor 940 and memory 930 configured to perform various functions described herein.

[0172] The communications manager 920 may support wireless communications at a first wireless device in accordance with examples as disclosed herein. For example, the communications manager 920 may be configured as or otherwise support a means for transmitting, to a second wireless device, control signaling indicating a quantity of feedback processes supported by the first wireless device and a retention duration associated with the quantity of feedback processes, where the retention duration corresponds to a time period during which the first wireless device stores decoding information of received packet data for a feedback process. The communications manager 920 may be configured as or otherwise support a means for transmitting a feedback message indicating unsuccessful decoding of a packet associated with a first feedback process of the quantity of feedback processes. The communications manager 920 may be configured as or otherwise support a means for receiving a control message scheduling a retransmission of the packet in accordance with the control signaling. The communications manager 920 may be configured as or otherwise support a means for receiving the retransmission of the packet based on the control message.

[0173] Additionally or alternatively, the communications manager 920 may support wireless communications at a first wireless device in accordance with examples as disclosed herein. For example, the communications manager 920 may be configured as or otherwise support a means for transmitting, to a second wireless device, an indication of a capability of the first wireless device, the capability including a threshold quantity of code blocks per transport block within a duration of time. The communications manager 920 may be configured as or otherwise support a means for receiving a control message scheduling a transmission of a packet based on transmitting the indication. The communications manager 920 may be configured as or otherwise support a means for communicating the scheduled transmission of the packet based on receiving the control message, the scheduled transmission including a quantity of code blocks that satisfies the threshold quantity of code blocks.

[0174] By including or configuring the communications manager 920 in accordance with examples as described herein, the device 905 may support feedback techniques as described herein. For example, such techniques may enable the device 905 to indicate the capability of the device 905, indicate dropped packets for feedback processes, and the like as described herein, which may result in increased power efficiency of the device 905, improved reliability of communications, reduced latency, improved user experience related to reduced processing, more efficient utilization of communication resources, improved coordination between devices, improved utilization of processing capability, or a combination thereof, among other advantages.

[0175] In some examples, the communications manager 920 may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using or otherwise in cooperation with the transceiver 915, the one or more antennas 925, or any combination thereof. Although the communications manager 920 is illustrated as a separate component, in some examples, one or more functions described with reference to the communications manager 920 may be supported by or performed by the processor 940, the memory 930, the code 935, or any combination thereof. For example, the code 935 may include instructions executable by the processor 940 to cause the device 905 to perform various aspects of hybrid automatic repeat request feedback techniques for wireless communications systems as described herein, or the processor 940 and the memory 930 may be otherwise configured to perform or support such operations.

[0176] FIG. 10 shows a diagram 1000 of a device 1005 that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure. The device 1005 may be an example of aspects of a UE 115, a base station 105, or any wireless device as described herein. The device 1005 may include a receiver 1010, a transmitter 1015, and a communications manager 1020. The device 1005 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

[0177] The receiver 1010 may provide a means for receiving information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to hybrid automatic repeat request feedback techniques for wireless communications systems). Information may be passed on to other components of the device 1005. The receiver 1010 may utilize a single antenna or a set of multiple antennas.

[0178] The transmitter 1015 may provide a means for transmitting signals generated by other components of the device 1005. For example, the transmitter 1015 may transmit information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to hybrid automatic repeat request feedback techniques for wireless communications systems). In some examples, the transmitter 1015 may be co-located with a receiver 1010 in a transceiver module. The transmitter 1015 may utilize a single antenna or a set of multiple antennas.

[0179] The communications manager 1020, the receiver 1010, the transmitter 1015, or various combinations thereof or various components thereof may be examples of means for performing various aspects of hybrid automatic repeat request feedback techniques for wireless communications systems as described herein. For example, the communications manager 1020, the receiver 1010, the transmitter 1015, or various combinations or components thereof may support a method for performing one or more of the functions described herein.

[0180] In some examples, the communications manager 1020, the receiver 1010, the transmitter 1015, or various combinations or components thereof may be implemented in hardware (e.g., in communications management circuitry). The hardware may include a processor, a DSP, an ASIC, an FPGA or other programmable logic device, a discrete gate or transistor logic, discrete hardware components, or any combination thereof configured as or otherwise supporting a means for performing the functions described in the present disclosure. In some examples, a processor and memory coupled with the processor may be configured to perform one or more of the functions described herein (e.g., by executing, by the processor, instructions stored in the memory).

[0181] Additionally or alternatively, in some examples, the communications manager 1020, the receiver 1010, the transmitter 1015, or various combinations or components thereof may be implemented in code (e.g., as communications management software or firmware) executed by a processor. If implemented in code executed by a processor, the functions of the communications manager 1020, the receiver 1010, the transmitter 1015, or various combinations or components thereof may be performed by a general-purpose processor, a DSP, a CPU, an ASIC, an FPGA, or any combination of these or other programmable logic devices (e.g., configured as or otherwise supporting a means for performing the functions described in the present disclosure). [0182] In some examples, the communications manager 1020 may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using or otherwise in cooperation with the receiver 1010, the transmitter 1015, or both. For example, the communications manager 1020 may receive information from the receiver 1010, send information to the transmitter 1015, or be integrated in combination with the receiver 1010, the transmitter 1015, or both to receive information, transmit information, or perform various other operations as described herein.

[0183] The communications manager 1020 may support wireless communications at a second wireless device in accordance with examples as disclosed herein. For example, the communications manager 1020 may be configured as or otherwise support a means for receiving, from a first wireless device, control signaling indicating a quantity of feedback processes supported by the first wireless device and a retention duration associated with the quantity of feedback processes, where the retention duration corresponds to a time period during which the first wireless device stores decoding information of received packet data for a feedback process. The communications manager 1020 may be configured as or otherwise support a means for receiving a feedback message indicating unsuccessful decoding of a packet associated with a first feedback process of the quantity of feedback processes. The communications manager 1020 may be configured as or otherwise support a means for transmitting a control message scheduling a retransmission of the packet in accordance with the control signaling. The communications manager 1020 may be configured as or otherwise support a means for transmitting the retransmission of the packet based on the control message.

[0184] Additionally or alternatively, the communications manager 1020 may support wireless communications at a second wireless device in accordance with examples as disclosed herein. For example, the communications manager 1020 may be configured as or otherwise support a means for receiving, from a first wireless device, an indication of a capability of the first wireless device, the capability including a threshold quantity of code blocks per transport block within a duration of time. The communications manager 1020 may be configured as or otherwise support a means for transmitting a control message scheduling a transmission of a packet based on receiving the indication. The communications manager 1020 may be configured as or otherwise support a means for communicating the scheduled transmission of the packet based on transmitting the control message, the scheduled transmission including a quantity of code blocks that satisfies the threshold quantity of code blocks.

[0185] By including or configuring the communications manager 1020 in accordance with examples as described herein, the device 1005 (e.g., a processor controlling or otherwise coupled to the receiver 1010, the transmitter 1015, the communications manager 1020, or a combination thereof) may support feedback techniques as described herein. For example, such techniques may enable the device 1005 to receive an indication of the capability of a first device, request a report of stored decoding information at a first device, and the like as described herein, which may result in increased power efficiency of the device 1005, improved reliability of communications, or both, among other advantages.

[0186] FIG. 11 shows a diagram 1100 of a device 1105 that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure. The device 1105 may be an example of aspects of a device 1005, a UE 115, a base station 105, or any wireless device as described herein. The device 1105 may include a receiver 1110, a transmitter 1115, and a communications manager 1120. The device 1105 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

[0187] The receiver 1110 may provide a means for receiving information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to hybrid automatic repeat request feedback techniques for wireless communications systems). Information may be passed on to other components of the device 1105. The receiver 1110 may utilize a single antenna or a set of multiple antennas.

[0188] The transmitter 1115 may provide a means for transmitting signals generated by other components of the device 1105. For example, the transmitter 1115 may transmit information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to hybrid automatic repeat request feedback techniques for wireless communications systems). In some examples, the transmitter 1115 may be co-located with a receiver 1110 in a transceiver module. The transmitter 1115 may utilize a single antenna or a set of multiple antennas.

[0189] The device 1105, or various components thereof, may be an example of means for performing various aspects of hybrid automatic repeat request feedback techniques for wireless communications systems as described herein. For example, the communications manager 1120 may include a control signaling module 1125, a feedback module 1130, a scheduling module 1135, a retransmission module 1140, a capability module 1145, a communication module 1150, or any combination thereof. The communications manager 1120 may be an example of aspects of a communications manager 1020 as described herein. In some examples, the communications manager 1120, or various components thereof, may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using or otherwise in cooperation with the receiver 1110, the transmitter 1115, or both. For example, the communications manager 1120 may receive information from the receiver 1110, send information to the transmitter 1115, or be integrated in combination with the receiver 1110, the transmitter 1115, or both to receive information, transmit information, or perform various other operations as described herein.

[0190] The communications manager 1120 may support wireless communications at a second wireless device in accordance with examples as disclosed herein. The control signaling module 1125 may be configured as or otherwise support a means for receiving, from a first wireless device, control signaling indicating a quantity of feedback processes supported by the first wireless device and a retention duration associated with the quantity of feedback processes, where the retention duration corresponds to a time period during which the first wireless device stores decoding information of received packet data for a feedback process. The feedback module 1130 may be configured as or otherwise support a means for receiving a feedback message indicating unsuccessful decoding of a packet associated with a first feedback process of the quantity of feedback processes. The scheduling module 1135 may be configured as or otherwise support a means for transmitting a control message scheduling a retransmission of the packet in accordance with the control signaling. The retransmission module 1140 may be configured as or otherwise support a means for transmitting the retransmission of the packet based on the control message.

[0191] Additionally or alternatively, the communications manager 1120 may support wireless communications at a second wireless device in accordance with examples as disclosed herein. The capability module 1145 may be configured as or otherwise support a means for receiving, from a first wireless device, an indication of a capability of the first wireless device, the capability including a threshold quantity of code blocks per transport block within a duration of time. The scheduling module 1135 may be configured as or otherwise support a means for transmitting a control message scheduling a transmission of a packet based on receiving the indication. The communication module 1150 may be configured as or otherwise support a means for communicating the scheduled transmission of the packet based on transmitting the control message, the scheduled transmission including a quantity of code blocks that satisfies the threshold quantity of code blocks.

[0192] FIG. 12 shows a diagram 1200 of a communications manager 1220 that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure. The communications manager 1220 may be an example of aspects of a communications manager 1020, a communications manager 1120, or both, as described herein. The communications manager 1220, or various components thereof, may be an example of means for performing various aspects of hybrid automatic repeat request feedback techniques for wireless communications systems as described herein. For example, the communications manager 1220 may include a control signaling module 1225, a feedback module 1230, a scheduling module 1235, a retransmission module 1240, a capability module 1245, a communication module 1250, or any combination thereof. Each of these components may communicate, directly or indirectly, with one another (e.g., via one or more buses).

[0193] The communications manager 1220 may support wireless communications at a second wireless device in accordance with examples as disclosed herein. The control signaling module 1225 may be configured as or otherwise support a means for receiving, from a first wireless device, control signaling indicating a quantity of feedback processes supported by the first wireless device and a retention duration associated with the quantity of feedback processes, where the retention duration corresponds to a time period during which the first wireless device stores decoding information of received packet data for a feedback process. The feedback module 1230 may be configured as or otherwise support a means for receiving a feedback message indicating unsuccessful decoding of a packet associated with a first feedback process of the quantity of feedback processes. The scheduling module 1235 may be configured as or otherwise support a means for transmitting a control message scheduling a retransmission of the packet in accordance with the control signaling. The retransmission module 1240 may be configured as or otherwise support a means for transmitting the retransmission of the packet based on the control message.

[0194] In some examples, to support transmitting the control message, the control signaling module 1225 may be configured as or otherwise support a means for transmitting the control message scheduling the retransmission of the packet that includes self-decodable data based on the retransmission of the packet being scheduled outside the time period or non-self-decodable data based on the retransmission of the packet being scheduled within the time period.

[0195] In some examples, the decoding information includes log likelihood ratio information for the packet.

[0196] In some examples, the control signaling module 1225 may be configured as or otherwise support a means for transmitting second control signaling indicating resources associated with reporting that the first wireless device has dropped the decoding information. In some examples, the feedback module 1230 may be configured as or otherwise support a means for receiving, via the indicated resources, an indication that the first wireless device has dropped the decoding information prior to an expiration of the retention duration.

[0197] In some examples, the communication module 1250 may be configured as or otherwise support a means for transmitting a message requesting that the first wireless device report a subset of feedback processes of the quantity of feedback processes for which the first wireless device is storing respective decoding information. In some examples, the feedback module 1230 may be configured as or otherwise support a means for receiving an indication of the subset of feedback processes from the first wireless device.

[0198] In some examples, to support receiving the control signaling, the control signaling module 1225 may be configured as or otherwise support a means for receiving the control signaling indicating a first group of feedback processes including the quantity of feedback processes, a second group of feedback processes, the retention duration corresponding to the first group of feedback processes, and a second retention duration corresponding to the second group of feedback processes.

[0199] In some examples, the retention duration includes a first quantity of slots during which the first wireless device stores decoding information for the first group of feedback processes. In some examples, the second retention duration includes a second quantity of slots during which the first wireless device stores decoding information for the second group of feedback processes.

[0200] In some examples, the control signaling indicates a set of multiple groups including the first group and the second group, each group of the set of multiple groups corresponding to a respective retention duration.

[0201] In some examples, the retransmission module 1240 may be configured as or otherwise support a means for transmitting the packet associated with the first feedback process based on the first feedback process being assigned to a first group of feedback processes including the quantity of feedback processes.

[0202] In some examples, to support transmitting the control message, the retransmission module 1240 may be configured as or otherwise support a means for transmitting the control message indicating a group identifier associated with the packet, the group identifier corresponding to the quantity of feedback processes and the retention duration.

[0203] In some examples, the retransmission module 1240 may be configured as or otherwise support a means for transmitting a second control message indicating a second group identifier for the packet, the second group identifier associated with a second quantity of feedback processes, a second retention duration, or any combination thereof. In some examples, the retransmission module 1240 may be configured as or otherwise support a means for transmitting a second retransmission of the packet in accordance with the second control message.

[0204] In some examples, the feedback module 1230 may be configured as or otherwise support a means for receiving, in response to the control message, an acknowledgement for the first feedback process based on the first wireless device storing first decoding information for the packet.

[0205] Additionally or alternatively, the communications manager 1220 may support wireless communications at a second wireless device in accordance with examples as disclosed herein. The capability module 1245 may be configured as or otherwise support a means for receiving, from a first wireless device, an indication of a capability of the first wireless device, the capability including a threshold quantity of code blocks per transport block within a duration of time. In some examples, the scheduling module 1235 may be configured as or otherwise support a means for transmitting a control message scheduling a transmission of a packet based on receiving the indication. The communication module 1250 may be configured as or otherwise support a means for communicating the scheduled transmission of the packet based on transmitting the control message, the scheduled transmission including a quantity of code blocks that satisfies the threshold quantity of code blocks.

[0206] In some examples, the capability module 1245 may be configured as or otherwise support a means for receiving a second indication of a capability of the first wireless device to communicate a fixed transport block size or a variable transport block size.

[0207] In some examples, the capability module 1245 may be configured as or otherwise support a means for receiving a second indication including a second threshold quantity of code blocks per transport block with the duration of time based on other communications in a network, a battery level of the first wireless device, one or more energy harvesting parameters, or any combination thereof.

[0208] FIG. 13 shows a diagram of a system 1300 including a device 1305 that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure. The device 1305 may be an example of or include the components of a device 1005, a device 1105, a UE 115, a base station 105, or any wireless device as described herein. The device 1305 may communicate wirelessly with one or more base stations 105, UEs 115, or any combination thereof. The device 1305 may include components for bidirectional voice and data communications including components for transmitting and receiving communications, such as a communications manager 1320, a network communications manager 1310, a transceiver 1315, an antenna 1325, a memory 1330, code 1335, a processor 1340, and an inter-station communications manager 1345. These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more buses (e.g., a bus 1350).

[0209] The network communications manager 1310 may manage communications with a core network 130 (e.g., via one or more wired backhaul links). For example, the network communications manager 1310 may manage the transfer of data communications for client devices, such as one or more UEs 115.

[0210] In some cases, the device 1305 may include a single antenna 1325. However, in some other cases the device 1305 may have more than one antenna 1325, which may be capable of concurrently transmitting or receiving multiple wireless transmissions. The transceiver 1315 may communicate bi-directionally, via the one or more antennas 1325, wired, or wireless links as described herein. For example, the transceiver 1315 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. The transceiver 1315 may also include a modem to modulate the packets, to provide the modulated packets to one or more antennas 1325 for transmission, and to demodulate packets received from the one or more antennas 1325. The transceiver 1315, or the transceiver 1315 and one or more antennas 1325, may be an example of a transmitter 1015, a transmitter 1115, a receiver 1010, a receiver 1110, or any combination thereof or component thereof, as described herein.

[0211] The memory 1330 may include RAM and ROM. The memory 1330 may store computer-readable, computer-executable code 1335 including instructions that, when executed by the processor 1340, cause the device 1305 to perform various functions described herein. The code 1335 may be stored in a non-transitory computer- readable medium such as system memory or another type of memory. In some cases, the code 1335 may not be directly executable by the processor 1340 but may cause a computer (e.g., when compiled and executed) to perform functions described herein. In some cases, the memory 1330 may contain, among other things, a BIOS which may control basic hardware or software operation such as the interaction with peripheral components or devices.

[0212] The processor 1340 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 1340 may be configured to operate a memory array using a memory controller. In some other cases, a memory controller may be integrated into the processor 1340. The processor 1340 may be configured to execute computer-readable instructions stored in a memory (e.g., the memory 1330) to cause the device 1305 to perform various functions (e.g., functions or tasks supporting hybrid automatic repeat request feedback techniques for wireless communications systems). For example, the device 1305 or a component of the device 1305 may include a processor 1340 and memory 1330 coupled to the processor 1340, the processor 1340 and memory 1330 configured to perform various functions described herein.

[0213] The inter-station communications manager 1345 may manage communications with other base stations 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 1345 may coordinate scheduling for transmissions to UEs 115 for various interference mitigation techniques such as beamforming or joint transmission. In some examples, the inter-station communications manager 1345 may provide an X2 interface within an LTE/LTE-A wireless communications network technology to provide communication between base stations 105.

[0214] The communications manager 1320 may support wireless communications at a second wireless device in accordance with examples as disclosed herein. For example, the communications manager 1320 may be configured as or otherwise support a means for receiving, from a first wireless device, control signaling indicating a quantity of feedback processes supported by the first wireless device and a retention duration associated with the quantity of feedback processes, where the retention duration corresponds to a time period during which the first wireless device stores decoding information of received packet data for a feedback process. The communications manager 1320 may be configured as or otherwise support a means for receiving a feedback message indicating unsuccessful decoding of a packet associated with a first feedback process of the quantity of feedback processes. The communications manager 1320 may be configured as or otherwise support a means for transmitting a control message scheduling a retransmission of the packet in accordance with the control signaling. The communications manager 1320 may be configured as or otherwise support a means for transmitting the retransmission of the packet based on the control message.

[0215] Additionally or alternatively, the communications manager 1320 may support wireless communications at a second wireless device in accordance with examples as disclosed herein. For example, the communications manager 1320 may be configured as or otherwise support a means for receiving, from a first wireless device, an indication of a capability of the first wireless device, the capability including a threshold quantity of code blocks per transport block within a duration of time. The communications manager 1320 may be configured as or otherwise support a means for transmitting a control message scheduling a transmission of a packet based on receiving the indication. The communications manager 1320 may be configured as or otherwise support a means for communicating the scheduled transmission of the packet based on transmitting the control message, the scheduled transmission including a quantity of code blocks that satisfies the threshold quantity of code blocks.

[0216] By including or configuring the communications manager 1320 in accordance with examples as described herein, the device 1305 may support feedback techniques as described herein. For example, such techniques may enable the device 1305 to receive an indication of the capability of a first device, request a report of stored decoding information at a first device, and the like as described herein, which may result in increased power efficiency of the device 1305, improved reliability of communications, reduced latency, improved user experience related to reduced processing, reduced power consumption, more efficient utilization of communication resources, improved coordination between devices, improved utilization of processing capability, or a combination thereof, among other advantages. [0217] In some examples, the communications manager 1320 may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using or otherwise in cooperation with the transceiver 1315, the one or more antennas 1325, or any combination thereof. Although the communications manager 1320 is illustrated as a separate component, in some examples, one or more functions described with reference to the communications manager 1320 may be supported by or performed by the processor 1340, the memory 1330, the code 1335, or any combination thereof. For example, the code 1335 may include instructions executable by the processor 1340 to cause the device 1305 to perform various aspects of hybrid automatic repeat request feedback techniques for wireless communications systems as described herein, or the processor 1340 and the memory 1330 may be otherwise configured to perform or support such operations.

[0218] FIG. 14 shows a flowchart illustrating a method 1400 that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure. The operations of the method 1400 may be implemented by a UE or its components as described herein. For example, the operations of the method 1400 may be performed by a UE 115 as described with reference to FIGs. 1 through 9. In some examples, a UE may execute a set of instructions to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may perform aspects of the described functions using special-purpose hardware.

[0219] At 1405, the method may include transmitting, to a second wireless device, control signaling indicating a quantity of feedback processes supported by the first wireless device and a retention duration associated with the quantity of feedback processes, where the retention duration corresponds to a time period during which the first wireless device stores decoding information of received packet data for a feedback process. The operations of 1405 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1405 may be performed by a control signal component 825 as described with reference to FIG. 8.

[0220] At 1410, the method may include transmitting a feedback message indicating unsuccessful decoding of a packet associated with a first feedback process of the quantity of feedback processes. The operations of 1410 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1410 may be performed by a feedback component 830 as described with reference to FIG. 8.

[0221] At 1415, the method may include receiving a control message scheduling a retransmission of the packet in accordance with the control signaling. The operations of 1415 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1415 may be performed by a scheduling component 835 as described with reference to FIG. 8.

[0222] At 1420, the method may include receiving the retransmission of the packet based on the control message. The operations of 1420 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1420 may be performed by a packet component 840 as described with reference to FIG. 8.

[0223] FIG. 15 shows a flowchart illustrating a method 1500 that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure. The operations of the method 1500 may be implemented by a base station or its components as described herein. For example, the operations of the method 1500 may be performed by a base station 105 as described with reference to FIGs. 1 through 5 and 10 through 13. In some examples, a base station may execute a set of instructions to control the functional elements of the base station to perform the described functions. Additionally or alternatively, the base station may perform aspects of the described functions using special-purpose hardware.

[0224] At 1505, the method may include receiving, from a first wireless device, control signaling indicating a quantity of feedback processes supported by the first wireless device and a retention duration associated with the quantity of feedback processes, where the retention duration corresponds to a time period during which the first wireless device stores decoding information of received packet data for a feedback process. The operations of 1505 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1505 may be performed by a control signaling module 1225 as described with reference to FIG. 12.

[0225] At 1510, the method may include receiving a feedback message indicating unsuccessful decoding of a packet associated with a first feedback process of the quantity of feedback processes. The operations of 1510 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1510 may be performed by a feedback module 1230 as described with reference to FIG. 12.

[0226] At 1515, the method may include transmitting a control message scheduling a retransmission of the packet in accordance with the control signaling. The operations of 1515 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1515 may be performed by a scheduling module 1235 as described with reference to FIG. 12.

[0227] At 1520, the method may include transmitting the retransmission of the packet based on the control message. The operations of 1520 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1520 may be performed by a retransmission module 1240 as described with reference to FIG. 12.

[0228] FIG. 16 shows a flowchart illustrating a method 1600 that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure. The operations of the method 1600 may be implemented by a UE or its components as described herein. For example, the operations of the method 1600 may be performed by a UE 115 as described with reference to FIGs. 1 through 9. In some examples, a UE may execute a set of instructions to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may perform aspects of the described functions using special-purpose hardware.

[0229] At 1605, the method may include transmitting, to a second wireless device, an indication of a capability of the first wireless device, the capability including a threshold quantity of code blocks per transport block within a duration of time. The operations of 1605 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1605 may be performed by a capability component 845 as described with reference to FIG. 8.

[0230] At 1610, the method may include receiving a control message scheduling a transmission of a packet based on transmitting the indication. The operations of 1610 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1610 may be performed by a scheduling component 835 as described with reference to FIG. 8.

[0231] At 1615, the method may include communicating the scheduled transmission of the packet based on receiving the control message, the scheduled transmission including a quantity of code blocks that satisfies the threshold quantity of code blocks. The operations of 1615 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1615 may be performed by a communication component 850 as described with reference to FIG. 8.

[0232] FIG. 17 shows a flowchart illustrating a method 1700 that supports hybrid automatic repeat request feedback techniques for wireless communications systems in accordance with aspects of the present disclosure. The operations of the method 1700 may be implemented by a base station or its components as described herein. For example, the operations of the method 1700 may be performed by a base station 105 as described with reference to FIGs. 1 through 5 and 10 through 13. In some examples, a base station may execute a set of instructions to control the functional elements of the base station to perform the described functions. Additionally or alternatively, the base station may perform aspects of the described functions using special-purpose hardware.

[0233] At 1705, the method may include receiving, from a first wireless device, an indication of a capability of the first wireless device, the capability including a threshold quantity of code blocks per transport block within a duration of time. The operations of 1705 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1705 may be performed by a capability module 1245 as described with reference to FIG. 12.

[0234] At 1710, the method may include transmitting a control message scheduling a transmission of a packet based on receiving the indication. The operations of 1710 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1710 may be performed by a scheduling module 1235 as described with reference to FIG. 12.

[0235] At 1715, the method may include communicating the scheduled transmission of the packet based on transmitting the control message, the scheduled transmission including a quantity of code blocks that satisfies the threshold quantity of code blocks. The operations of 1715 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1715 may be performed by a communication module 1250 as described with reference to FIG. 12.

[0236] The following provides an overview of aspects of the present disclosure:

[0237] Aspect 1 : A method for wireless communications at a first wireless device, comprising: transmitting, to a second wireless device, control signaling indicating a quantity of feedback processes supported by the first wireless device and a retention duration associated with the quantity of feedback processes, wherein the retention duration corresponds to a time period during which the first wireless device stores decoding information of received packet data for a feedback process; transmitting a feedback message indicating unsuccessful decoding of a packet associated with a first feedback process of the quantity of feedback processes; and receiving a control message scheduling a retransmission of the packet in accordance with the control signaling; and receiving the retransmission of the packet based at least in part on the control message.

[0238] Aspect 2: The method of aspect 1, wherein receiving the control message comprises: receiving the control message scheduling the retransmission of the packet that comprises self-decodable data based at least in part on the retransmission of the packet being scheduled outside the time period or non-self-decodable data based at least in part on the retransmission of the packet being scheduled within the time period.

[0239] Aspect 3: The method of any of aspects 1 through 2, wherein the decoding information comprises log likelihood ratio information for the packet.

[0240] Aspect 4: The method of any of aspects 1 through 3, further comprising: receiving second control signaling indicating resources associated with reporting that the first wireless device has dropped the decoding information; and transmitting, via the indicated resources, an indication that the first wireless device has dropped the decoding information prior to an expiration of the retention duration.

[0241] Aspect 5: The method of any of aspects 1 through 4, further comprising: receiving a message requesting that the first wireless device report a subset of feedback processes of the quantity of feedback processes for which the first wireless device is storing respective decoding information; and transmitting an indication of the subset of feedback processes to the second wireless device.

[0242] Aspect 6: The method of any of aspects 1 through 5, wherein transmitting the control signaling comprises: transmitting the control signaling indicating a first group of feedback processes comprising the quantity of feedback processes, a second group of feedback processes, the retention duration corresponding to the first group of feedback processes, and a second retention duration corresponding to the second group of feedback processes.

[0243] Aspect 7: The method of aspect 6, wherein the retention duration comprises a first quantity of slots during which the first wireless device stores decoding information for the first group of feedback processes; and the second retention duration comprises a second quantity of slots during which the first wireless device stores decoding information for the second group of feedback processes.

[0244] Aspect 8: The method of any of aspects 6 through 7, wherein the control signaling indicates a plurality of groups comprising the first group and the second group, each group of the plurality of groups corresponding to a respective retention duration.

[0245] Aspect 9: The method of any of aspects 1 through 8, further comprising: receiving the packet associated with the first feedback process based at least in part on the first feedback process being assigned to a first group of feedback processes comprising the quantity of feedback processes.

[0246] Aspect 10: The method of any of aspects 1 through 9, wherein receiving the control message comprises: receiving the control message indicating a group identifier associated with the packet, the group identifier corresponding to the quantity of feedback processes and the retention duration.

[0247] Aspect 11 : The method of aspect 10, further comprising: receiving a second control message indicating a second group identifier for the packet, the second group identifier associated with a second quantity of feedback processes, a second retention duration, or any combination thereof; and receiving a second retransmission of the packet in accordance with the second control message. [0248] Aspect 12: The method of any of aspects 1 through 11, further comprising: transmitting, in response to the control message, an acknowledgement for the first feedback process based at least in part on the first wireless device storing first decoding information for the packet.

[0249] Aspect 13: A method for wireless communications at a second wireless device, comprising: receiving, from a first wireless device, control signaling indicating a quantity of feedback processes supported by the first wireless device and a retention duration associated with the quantity of feedback processes, wherein the retention duration corresponds to a time period during which the first wireless device stores decoding information of received packet data for a feedback process; receiving a feedback message indicating unsuccessful decoding of a packet associated with a first feedback process of the quantity of feedback processes; transmitting a control message scheduling a retransmission of the packet in accordance with the control signaling; and transmitting the retransmission of the packet based at least in part on the control message.

[0250] Aspect 14: The method of aspect 13, wherein transmitting the control message comprises: transmitting the control message scheduling the retransmission of the packet that comprises self-decodable data based at least in part on the retransmission of the packet being scheduled outside the time period or non-self-decodable data based at least in part on the retransmission of the packet being scheduled within the time period.

[0251] Aspect 15: The method of any of aspects 13 through 14, wherein the decoding information comprises log likelihood ratio information for the packet.

[0252] Aspect 16: The method of any of aspects 13 through 15, further comprising: transmitting second control signaling indicating resources associated with reporting that the first wireless device has dropped the decoding information; and receiving, via the indicated resources, an indication that the first wireless device has dropped the decoding information prior to an expiration of the retention duration.

[0253] Aspect 17: The method of any of aspects 13 through 16, further comprising: transmitting a message requesting that the first wireless device report a subset of feedback processes of the quantity of feedback processes for which the first wireless device is storing respective decoding information; and receiving an indication of the subset of feedback processes from the first wireless device.

[0254] Aspect 18: The method of any of aspects 13 through 17, wherein receiving the control signaling comprises: receiving the control signaling indicating a first group of feedback processes comprising the quantity of feedback processes, a second group of feedback processes, the retention duration corresponding to the first group of feedback processes, and a second retention duration corresponding to the second group of feedback processes.

[0255] Aspect 19: The method of aspect 18, wherein the retention duration comprises a first quantity of slots during which the first wireless device stores decoding information for the first group of feedback processes; and the second retention duration comprises a second quantity of slots during which the first wireless device stores decoding information for the second group of feedback processes.

[0256] Aspect 20: The method of any of aspects 18 through 19, wherein the control signaling indicates a plurality of groups comprising the first group and the second group, each group of the plurality of groups corresponding to a respective retention duration.

[0257] Aspect 21 : The method of any of aspects 13 through 20, further comprising: transmitting the packet associated with the first feedback process based at least in part on the first feedback process being assigned to a first group of feedback processes comprising the quantity of feedback processes.

[0258] Aspect 22: The method of any of aspects 13 through 21, wherein transmitting the control message comprises: transmitting the control message indicating a group identifier associated with the packet, the group identifier corresponding to the quantity of feedback processes and the retention duration.

[0259] Aspect 23: The method of aspect 22, further comprising: transmitting a second control message indicating a second group identifier for the packet, the second group identifier associated with a second quantity of feedback processes, a second retention duration, or any combination thereof; and transmitting a second retransmission of the packet in accordance with the second control message. [0260] Aspect 24: The method of any of aspects 13 through 23, further comprising: receiving, in response to the control message, an acknowledgement for the first feedback process based at least in part on the first wireless device storing first decoding information for the packet.

[0261] Aspect 25: A method for wireless communications at a first wireless device, comprising: transmitting, to a second wireless device, an indication of a capability of the first wireless device, the capability comprising a threshold quantity of code blocks per transport block within a duration of time; receiving a control message scheduling a transmission of a packet based at least in part on transmitting the indication; and communicating the scheduled transmission of the packet based at least in part on receiving the control message, the scheduled transmission comprising a quantity of code blocks that satisfies the threshold quantity of code blocks.

[0262] Aspect 26: The method of aspect 25, further comprising: transmitting a second indication of a capability of the first wireless device to communicate a fixed transport block size or a variable transport block size.

[0263] Aspect 27: The method of any of aspects 25 through 26, further comprising: transmitting a second indication comprising a second threshold quantity of code blocks per transport block with the duration of time based at least in part on other communications in a network, a battery level of the first wireless device, one or more energy harvesting parameters, or any combination thereof.

[0264] Aspect 28: A method for wireless communications at a second wireless device, comprising: receiving, from a first wireless device, an indication of a capability of the first wireless device, the capability comprising a threshold quantity of code blocks per transport block within a duration of time; transmitting a control message scheduling a transmission of a packet based at least in part on receiving the indication; and communicating the scheduled transmission of the packet based at least in part on transmitting the control message, the scheduled transmission comprising a quantity of code blocks that satisfies the threshold quantity of code blocks.

[0265] Aspect 29: The method of aspect 28, further comprising: receiving a second indication of a capability of the first wireless device to communicate a fixed transport block size or a variable transport block size. [0266] Aspect 30: The method of any of aspects 28 through 29, further comprising: receiving a second indication comprising a second threshold quantity of code blocks per transport block with the duration of time based at least in part on other communications in a network, a battery level of the first wireless device, one or more energy harvesting parameters, or any combination thereof.

[0267] Aspect 31 : An apparatus for wireless communications at a first wireless device, comprising a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform a method of any of aspects 1 through 12.

[0268] Aspect 32: An apparatus for wireless communications at a first wireless device, comprising at least one means for performing a method of any of aspects 1 through 12.

[0269] Aspect 33: A non-transitory computer-readable medium storing code for wireless communications at a first wireless device, the code comprising instructions executable by a processor to perform a method of any of aspects 1 through 12.

[0270] Aspect 34: An apparatus for wireless communications at a second wireless device, comprising a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform a method of any of aspects 13 through 24.

[0271] Aspect 35: An apparatus for wireless communications at a second wireless device, comprising at least one means for performing a method of any of aspects 13 through 24.

[0272] Aspect 36: A non-transitory computer-readable medium storing code for wireless communications at a second wireless device, the code comprising instructions executable by a processor to perform a method of any of aspects 13 through 24.

[0273] Aspect 37: An apparatus for wireless communications at a first wireless device, comprising a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform a method of any of aspects 25 through 27. [0274] Aspect 38: An apparatus for wireless communications at a first wireless device, comprising at least one means for performing a method of any of aspects 25 through 27.

[0275] Aspect 39: A non-transitory computer-readable medium storing code for wireless communications at a first wireless device, the code comprising instructions executable by a processor to perform a method of any of aspects 25 through 27.

[0276] Aspect 40: An apparatus for wireless communications at a second wireless device, comprising a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform a method of any of aspects 28 through 30.

[0277] Aspect 41: An apparatus for wireless communications at a second wireless device, comprising at least one means for performing a method of any of aspects 28 through 30.

[0278] Aspect 42: A non-transitory computer-readable medium storing code for wireless communications at a second wireless device, the code comprising instructions executable by a processor to perform a method of any of aspects 28 through 30.

[0279] 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.

[0280] 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.

[0281] 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.

[0282] 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).

[0283] Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A non-transitory storage medium may be any available medium that may be accessed by a general-purpose or special-purpose computer. By way of example, and not limitation, non-transitory computer-readable media may include RAM, ROM, electrically erasable programmable ROM (EEPROM), flash memory, compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that may be used to carry or store desired program code means in the form of instructions or data structures and that may be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor. Also, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of computer-readable medium. Disk and disc, as used herein, include CD, laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above are also included within the scope of computer-readable media.

[0284] 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 and spirit 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. As used herein, including in the claims, the term “and/or,” when used in a list of two or more items, means that any one of the listed items can be employed by itself, or any combination of two or more of the listed items can be employed. For example, if a composition is described as containing components A, B, and/or C, the composition can contain A alone; B alone; C alone; A and B in combination; A and C in combination; B and C in combination; or A, B, and C in combination. 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 a disjunctive 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).

[0285] The term “determine” or “determining” encompasses a wide variety of actions and, therefore, “determining” can include calculating, computing, processing, deriving, investigating, looking up (such as via looking up in a table, a database or another data structure), ascertaining and the like. Also, “determining” can include receiving (such as receiving information), accessing (such as accessing data in a memory) and the like. Also, “determining” can include resolving, selecting, choosing, establishing and other such similar actions.

[0286] 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.

[0287] 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 diagram form in order to avoid obscuring the concepts of the described examples.

[0288] 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

78 CLAIMS What is claimed is:

1. A method for wireless communications at a first wireless device, comprising: transmitting, to a second wireless device, control signaling indicating a quantity of feedback processes supported by the first wireless device and a retention duration associated with the quantity of feedback processes, wherein the retention duration corresponds to a time period during which the first wireless device stores decoding information of received packet data for a feedback process; transmitting a feedback message indicating unsuccessful decoding of a packet associated with a first feedback process of the quantity of feedback processes; and receiving a control message scheduling a retransmission of the packet in accordance with the control signaling; and receiving the retransmission of the packet based at least in part on the control message.

2. The method of claim 1, wherein receiving the control message comprises: receiving the control message scheduling the retransmission of the packet that comprises self-decodable data based at least in part on the retransmission of the packet being scheduled outside the time period or non-self-decodable data based at least in part on the retransmission of the packet being scheduled within the time period.

3. The method of claim 1, wherein the decoding information comprises log likelihood ratio information for the packet.

4. The method of claim 1 , further comprising: receiving second control signaling indicating resources associated with reporting that the first wireless device has dropped the decoding information; and transmitting, via the indicated resources, an indication that the first wireless device has dropped the decoding information prior to an expiration of the retention duration.

5. The method of claim 1 , further comprising: 79 receiving a message requesting that the first wireless device report a subset of feedback processes of the quantity of feedback processes for which the first wireless device is storing respective decoding information; and transmitting an indication of the subset of feedback processes to the second wireless device.

6. The method of claim 1, wherein transmitting the control signaling comprises: transmitting the control signaling indicating a first group of feedback processes comprising the quantity of feedback processes, a second group of feedback processes, the retention duration corresponding to the first group of feedback processes, and a second retention duration corresponding to the second group of feedback processes.

7. The method of claim 6, wherein: the retention duration comprises a first quantity of slots during which the first wireless device stores decoding information for the first group of feedback processes; and the second retention duration comprises a second quantity of slots during which the first wireless device stores decoding information for the second group of feedback processes.

8. The method of claim 6, wherein the control signaling indicates a plurality of groups comprising the first group and the second group, each group of the plurality of groups corresponding to a respective retention duration.

9. The method of claim 1 , further comprising: receiving the packet associated with the first feedback process based at least in part on the first feedback process being assigned to a first group of feedback processes comprising the quantity of feedback processes.

10. The method of claim 1, wherein receiving the control message comprises: receiving the control message indicating a group identifier associated with the packet, the group identifier corresponding to the quantity of feedback processes and the retention duration. 80

11. The method of claim 10, further comprising: receiving a second control message indicating a second group identifier for the packet, the second group identifier associated with a second quantity of feedback processes, a second retention duration, or any combination thereof; and receiving a second retransmission of the packet in accordance with the second control message.

12. The method of claim 1, further comprising: transmitting, in response to the control message, an acknowledgement for the first feedback process based at least in part on the first wireless device storing first decoding information for the packet.

13. A method for wireless communications at a second wireless device, comprising: receiving, from a first wireless device, control signaling indicating a quantity of feedback processes supported by the first wireless device and a retention duration associated with the quantity of feedback processes, wherein the retention duration corresponds to a time period during which the first wireless device stores decoding information of received packet data for a feedback process; receiving a feedback message indicating unsuccessful decoding of a packet associated with a first feedback process of the quantity of feedback processes; transmitting a control message scheduling a retransmission of the packet in accordance with the control signaling; and transmitting the retransmission of the packet based at least in part on the control message.

14. The method of claim 13, wherein transmitting the control message comprises: transmitting the control message scheduling the retransmission of the packet that comprises self-decodable data based at least in part on the retransmission of the packet being scheduled outside the time period or non-self-decodable data based at least in part on the retransmission of the packet being scheduled within the time period. 81

15. The method of claim 13, wherein the decoding information comprises log likelihood ratio information for the packet.

16. The method of claim 13, further comprising: transmitting second control signaling indicating resources associated with reporting that the first wireless device has dropped the decoding information; and receiving, via the indicated resources, an indication that the first wireless device has dropped the decoding information prior to an expiration of the retention duration.

17. The method of claim 13, further comprising: transmitting a message requesting that the first wireless device report a subset of feedback processes of the quantity of feedback processes for which the first wireless device is storing respective decoding information; and receiving an indication of the subset of feedback processes from the first wireless device.

18. The method of claim 13, wherein receiving the control signaling comprises: receiving the control signaling indicating a first group of feedback processes comprising the quantity of feedback processes, a second group of feedback processes, the retention duration corresponding to the first group of feedback processes, and a second retention duration corresponding to the second group of feedback processes.

19. The method of claim 18, wherein: the retention duration comprises a first quantity of slots during which the first wireless device stores decoding information for the first group of feedback processes; and the second retention duration comprises a second quantity of slots during which the first wireless device stores decoding information for the second group of feedback processes.

20. The method of claim 18, wherein the control signaling indicates a plurality of groups comprising the first group and the second group, each group of the plurality of groups corresponding to a respective retention duration.

21. The method of claim 13, further comprising: 82 transmitting the packet associated with the first feedback process based at least in part on the first feedback process being assigned to a first group of feedback processes comprising the quantity of feedback processes.

22. The method of claim 13, wherein transmitting the control message comprises: transmitting the control message indicating a group identifier associated with the packet, the group identifier corresponding to the quantity of feedback processes and the retention duration.

23. The method of claim 22, further comprising: transmitting a second control message indicating a second group identifier for the packet, the second group identifier associated with a second quantity of feedback processes, a second retention duration, or any combination thereof; and transmitting a second retransmission of the packet in accordance with the second control message.

24. The method of claim 13, further comprising: receiving, in response to the control message, an acknowledgement for the first feedback process based at least in part on the first wireless device storing first decoding information for the packet.

25. A method for wireless communications at a first wireless device, comprising: transmitting, to a second wireless device, an indication of a capability of the first wireless device, the capability comprising a threshold quantity of code blocks per transport block within a duration of time; receiving a control message scheduling a transmission of a packet based at least in part on transmitting the indication; and communicating the scheduled transmission of the packet based at least in part on receiving the control message, the scheduled transmission comprising a quantity of code blocks that satisfies the threshold quantity of code blocks.

26. The method of claim 25, further comprising: 83 transmitting a second indication of a capability of the first wireless device to communicate a fixed transport block size or a variable transport block size.

27. The method of claim 25, further comprising: transmitting a second indication comprising a second threshold quantity of code blocks per transport block with the duration of time based at least in part on other communications in a network, a battery level of the first wireless device, one or more energy harvesting parameters, or any combination thereof.

28. A method for wireless communications at a second wireless device, comprising: receiving, from a first wireless device, an indication of a capability of the first wireless device, the capability comprising a threshold quantity of code blocks per transport block within a duration of time; transmitting a control message scheduling a transmission of a packet based at least in part on receiving the indication; and communicating the scheduled transmission of the packet based at least in part on transmitting the control message, the scheduled transmission comprising a quantity of code blocks that satisfies the threshold quantity of code blocks.

29. The method of claim 28, further comprising: receiving a second indication of a capability of the first wireless device to communicate a fixed transport block size or a variable transport block size.

30. The method of claim 28, further comprising: receiving a second indication comprising a second threshold quantity of code blocks per transport block with the duration of time based at least in part on other communications in a network, a battery level of the first wireless device, one or more energy harvesting parameters, or any combination thereof.