Contention Resolution in New Radio Non-Terrestrial Networks

Abstract

Methods, systems, and apparatus for wireless communications are described. A communications device (also referred to as user equipment (UE)) may transmit a random access message (e.g., Message 3) associated with a random access procedure. Hybrid automatic repeat request (HARQ) feedback may be disabled for the random access procedure. The UE may initiate a contention resolution window associated with the random access procedure for a first downlink data channel transmission associated with the random access procedure in a set of downlink data channel transmissions. The UE may receive the first downlink data channel transmission during the contention resolution window, the first downlink data channel transmission carrying a contention resolution medium access control element (MAC-CE). The UE may transmit, based on an indication that HARQ feedback is to be enabled, an acknowledgment of the first downlink data channel transmission carrying the contention resolution MAC-CE.

Description

[0001] Cross-references

[0002] This patent application claims the benefit of U.S. Provisional Patent Application No. 62 / 980,103, filed by Shrestha et al. on February 21, 2020, entitled “Contention Resolution in New Radio Non-Terrestrial Networks,” and U.S. Patent Application No. 17 / 179,019, filed by Shrestha et al. on February 18, 2021, entitled “Contention Resolution in New Radio Non-Terrestrial Networks,” each of which is assigned to the assignee of this application.

[0003] introduction

[0004] The following relates to wireless communications, and more particularly to contention resolution for a contention-based random access procedure.

[0005] Communication systems are widely deployed to provide various types of communication content, such as voice, video, packet data, messaging, broadcasting, and the like. These systems may be able to support communication with multiple users by sharing 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, advanced LTE (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 various technologies, such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal frequency division multiple access (OFDMA), or discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM). A communication system may include one or more base stations or one or more network access nodes, each base station or network access node simultaneously supporting communication with multiple communication devices, which may be further referred to as user equipment (UE).

[0006] Overview

[0007] A method for wireless communication at a UE is described. The method may include: determining that hybrid automatic repeat request (HARQ) feedback is disabled; and transmitting a random access message associated with a random access procedure to a base station based on determining that the HARQ feedback is disabled. The method may further include initiating a contention resolution window associated with the random access procedure for a downlink data channel transmission from a set of multiple downlink data channel transmissions associated with the random access procedure. The method may further include receiving the downlink data channel transmission during the contention resolution window, the downlink data channel transmission carrying a contention resolution medium access control-control element (MAC-CE).

[0008] An apparatus for wireless communication at a UE is described. The apparatus may include a processor; and a memory coupled to the processor, the processor and the memory being configured to: determine that HARQ feedback is disabled; and transmit a random access message associated with a random access procedure to a base station based on the determination that HARQ feedback is disabled. The processor and the memory may be further configured to: initiate a contention resolution window associated with the random access procedure for a downlink data channel transmission in a set of multiple downlink data channel transmissions associated with the random access procedure. The processor and the memory may be further configured to: receive the downlink data channel transmission during the contention resolution window, the downlink data channel transmission carrying a contention resolution MAC-CE.

[0009] Another apparatus for wireless communication at a UE is described. The apparatus may include: means for determining that HARQ feedback is disabled; and means for transmitting a random access message associated with a random access procedure to a base station based on determining that HARQ feedback is disabled. The apparatus may further include: means for initiating a contention resolution window associated with the random access procedure for a downlink data channel transmission from a set of multiple downlink data channel transmissions associated with the random access procedure. The apparatus may further include: means for receiving the downlink data channel transmission during the contention resolution window, the downlink data channel transmission carrying a contention resolution MAC-CE.

[0010] A non-transitory computer-readable medium storing code for wireless communication at a UE is described. The code may include instructions executable by a processor to: determine that HARQ feedback is disabled; and transmit a random access message associated with a random access procedure to a base station based on the determination that HARQ feedback is disabled. The code may further include instructions executable by the processor to: initiate a contention resolution window associated with the random access procedure for a downlink data channel transmission from a set of multiple downlink data channel transmissions associated with the random access procedure. The code may further include instructions executable by the processor to: receive the downlink data channel transmission during the contention resolution window, the downlink data channel transmission carrying a contention resolution MAC-CE.

[0011] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, the random access message includes a random access message 3 (msg3). Some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for the following actions: transmitting, based on an indication that HARQ feedback is to be enabled for the random access procedure, an acknowledgment of the downlink data channel transmission carrying the contention resolution MAC-CE.

[0012] Some examples of the methods, devices (apparatuses), and non-transitory computer-readable media described herein may further include operations, features, apparatuses, or instructions for: identifying an indication to enable HARQ feedback based on UE context information, a network configuration for enabling HARQ feedback, a default configuration for enabling HARQ feedback, or a combination thereof; and enabling HARQ feedback based on the identification.

[0013] Some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for the following actions: transmitting, in the random access message, a request to enable HARQ feedback for the downlink data channel transmission carrying the contention resolution MAC-CE. Some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for the following actions: receiving an indication in a contention resolution MAC-CE; and enabling HARQ feedback based on the indication in the contention resolution MAC-CE.

[0014] Some examples of the methods, devices, and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for: receiving a downlink control information (DCI) message that schedules a downlink data channel transmission carrying the contention resolution MAC-CE. In some examples of the methods, devices, and non-transitory computer-readable media described herein, the DCI message includes an indication that HARQ feedback is to be enabled.

[0015] Some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for determining resources associated with an uplink control channel based on a second indication in a contention resolution MAC-CE. In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, transmitting an acknowledgment may include operations, features, means, or instructions for transmitting an acknowledgment on an uplink control channel using the determined resources.

[0016] In some examples of the methods, devices, and non-transitory computer-readable media described herein, the second indication includes a new MAC-CE providing uplink control channel resources. In some examples of the methods, devices, and non-transitory computer-readable media described herein, the logical channel identifier of the new MAC-CE may be the same as or different from the contention resolution MAC-CE.

[0017] Some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for determining a reception failure of a downlink data channel transmission carrying a contention resolution MAC-CE. In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, HARQ feedback may be enabled for a random access procedure, and the acknowledgment information may include a negative acknowledgment.

[0018] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, transmitting acknowledgment information may include operations, features, means, or instructions for transmitting acknowledgment information based on elapsed contention resolution window. In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, HARQ feedback may be enabled for a random access procedure, and the acknowledgment information may include a negative acknowledgment.

[0019] Some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for receiving a radio resource control (RRC) message including an indication to disable HARQ feedback for a random access procedure. In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, determining that HARQ feedback may be disabled may be based on receiving the RRC message.

[0020] Some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein may further include operations, features, apparatus, or instructions for: receiving a random access response message associated with a random access procedure, the random access response message including a timing advance; and controlling an uplink alignment timer based on the timing advance or disabled HARQ feedback for the random access procedure, or both.

[0021] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, the base station is a non-terrestrial base station including a satellite or a high-altitude platform station in a non-terrestrial network.

[0022] A method of wireless communication at a base station is described. The method may include receiving a random access message associated with a random access procedure from a UE, wherein HARQ feedback is disabled, and wherein a contention resolution window is associated with the random access procedure for downlink data channel transmissions in a set of multiple downlink data channel transmissions associated with the random access procedure. The method may further include transmitting the downlink data channel transmission during the contention resolution window, the downlink data channel transmission carrying a contention resolution MAC-CE.

[0023] An apparatus for wireless communication at a base station is described. The apparatus may include a processor and a memory coupled to the processor, the processor and the memory being configured to receive a random access message associated with a random access procedure from a UE, wherein HARQ feedback is disabled, and wherein a contention resolution window is associated with the random access procedure for downlink data channel transmissions from a set of multiple downlink data channel transmissions associated with the random access procedure. The processor and the memory may be further configured to transmit the downlink data channel transmission during the contention resolution window, the downlink data channel transmission carrying a contention resolution MAC-CE.

[0024] Another apparatus for wireless communication at a base station is described. The apparatus may include means for receiving a random access message associated with a random access procedure from a UE, wherein HARQ feedback is disabled, and wherein a contention resolution window is associated with the random access procedure for downlink data channel transmissions in a set of multiple downlink data channel transmissions associated with the random access procedure. The apparatus may further include means for transmitting the downlink data channel transmission during the contention resolution window, the downlink data channel transmission carrying a contention resolution MAC-CE.

[0025] A non-transitory computer-readable medium storing code for wireless communication at a base station is described. The code may include instructions executable by a processor to: receive a random access message associated with a random access procedure from a UE, wherein HARQ feedback is disabled, and wherein a contention resolution window is associated with the random access procedure for downlink data channel transmissions in a set of multiple downlink data channel transmissions associated with the random access procedure. The code may further include instructions executable by the processor to: transmit the downlink data channel transmission during the contention resolution window, the downlink data channel transmission carrying a contention resolution MAC-CE.

[0026] Some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for the following actions: receiving an acknowledgment of a downlink data channel transmission carrying the contention resolution MAC-CE based on transmitting an indication to the UE that HARQ feedback is to be enabled. Some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for the following actions: transmitting an indication in a contention resolution MAC-CE.

[0027] A method for wireless communication at a UE is described. The method may include determining that HARQ feedback is disabled for a random access procedure; and transmitting a random access message associated with the random access procedure to a base station based on the determination that HARQ feedback is disabled for the random access procedure. The method may further include refraining from transmitting acknowledgment information regarding a downlink data channel transmission carrying a random access response message including a contention resolution MAC-CE based on the disabled HARQ feedback.

[0028] An apparatus for wireless communication at a user equipment terminal (UE) is described. The apparatus may include a processor and a memory coupled to the processor, the processor and the memory configured to: determine that HARQ feedback is disabled for a random access procedure; and transmit a random access message associated with the random access procedure to a base station based on the determination that HARQ feedback is disabled for the random access procedure. The processor and the memory may be further configured to: refrain from transmitting acknowledgment information regarding a downlink data channel transmission carrying a random access response message including a contention resolution MAC-CE based on the disabled HARQ feedback.

[0029] Another apparatus for wireless communication at a UE is described. The apparatus may include: means for determining that HARQ feedback is disabled for a random access procedure; and means for transmitting a random access message associated with the random access procedure to a base station based on the determination that HARQ feedback is disabled for the random access procedure. The apparatus may further include: means for refraining from transmitting acknowledgment information regarding a downlink data channel transmission carrying a random access response message including a contention resolution MAC-CE based on the disabled HARQ feedback.

[0030] A non-transitory computer-readable medium storing code for wireless communication at a UE is described. The code may include instructions executable by a processor to: determine that HARQ feedback is disabled for a random access procedure; and based on the determination that HARQ feedback is disabled for the random access procedure, transmit a random access message associated with the random access procedure to a base station. The code may further include instructions executable by the processor to: refrain from transmitting acknowledgment information regarding a downlink data channel transmission carrying a random access response message including a contention resolution MAC-CE based on the disabled HARQ feedback.

[0031] In some examples of the methods, devices, and non-transitory computer-readable media described herein, the random access message includes msg3. Some examples of the methods, devices, and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for: monitoring a contention resolution window associated with a random access procedure for a number of repetitions associated with a downlink data channel transmission carrying the contention resolution MAC-CE. Some examples of the methods, devices, and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for: receiving a configuration including an indication of a number of repetitions associated with a downlink data channel transmission carrying the contention resolution MAC-CE.

[0032] Some examples of the methods, devices, and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for: receiving a downlink control channel carrying a DCI message that schedules one or more transport blocks associated with a repetition number of downlink data channel transmissions associated with the contention resolution MAC-CE.

[0033] Some examples of the methods, devices, and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for starting a contention resolution timer associated with the contention resolution window. In some examples of the methods, devices, and non-transitory computer-readable media described herein, monitoring the contention resolution window may be based on the contention resolution timer. In some examples of the methods, devices, and non-transitory computer-readable media described herein, the random access response message further includes a service data unit (SDU) associated with a downlink common control channel.

[0034] A method for wireless communication at a UE is described. The method may include transmitting a random access message associated with a random access procedure to a base station. The method may further include receiving a configuration regarding a contention resolution timer; and setting a value for the contention resolution timer based on the configuration. The method may further include monitoring a contention resolution window associated with the random access procedure based on the value of the contention resolution timer to search for a first downlink data channel transmission in a set of multiple downlink data channel transmissions associated with the random access procedure, the first downlink data channel transmission carrying a contention resolution MAC-CE. The method may further include transmitting an acknowledgment regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0035] A device for wireless communication at a UE is described. The device may include a processor; and a memory coupled to the processor, the processor and the memory being configured to: transmit a random access message associated with a random access procedure to a base station. The processor and the memory may be further configured to receive a configuration regarding a contention resolution timer; and set a value for the contention resolution timer based on the configuration. The processor and the memory may be further configured to monitor a contention resolution window associated with the random access procedure based on the value of the contention resolution timer set to search for a first downlink data channel transmission in a set of multiple downlink data channel transmissions associated with the random access procedure, the first downlink data channel transmission carrying a contention resolution MAC-CE. The processor and the memory may be further configured to transmit acknowledgment information regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0036] Another apparatus for wireless communication at a UE is described. The apparatus may include means for transmitting a random access message associated with a random access procedure to a base station. The apparatus may further include means for receiving a configuration regarding a contention resolution timer; and means for setting a value for the contention resolution timer based on the configuration. The apparatus may further include means for monitoring a contention resolution window associated with the random access procedure based on the value of the contention resolution timer to search for a first downlink data channel transmission in a set of multiple downlink data channel transmissions associated with the random access procedure, the first downlink data channel transmission carrying a contention resolution MAC-CE. The apparatus may further include means for transmitting acknowledgment information regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0037] A non-transitory computer-readable medium storing code for wireless communication at a UE is described. The code may include instructions executable by a processor to perform the following operations: transmit a random access message associated with a random access procedure to a base station. The code may further include instructions executable by the processor to perform the following operations: receive a configuration regarding a contention resolution timer; and set a value for the contention resolution timer based on the configuration. The code may further include instructions executable by the processor to perform the following operations: monitor a contention resolution window associated with the random access procedure based on the value of the contention resolution timer to search for a first downlink data channel transmission in a set of multiple downlink data channel transmissions associated with the random access procedure, the first downlink data channel transmission carrying a contention resolution MAC-CE. The code may further include instructions executable by the processor to perform the following operations: transmit acknowledgment information regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0038] Some examples of the methods, devices, and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for: receiving a DCI message scheduling a second downlink data channel transmission carrying a second contention resolution MAC-CE in a set including a plurality of downlink data channel transmissions. In some examples of the methods, devices, and non-transitory computer-readable media described herein, the DCI message includes an indication to disable HARQ feedback for the second downlink data channel transmission.

[0039] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, a value of the contention resolution timer may be based on one or more of: a maximum propagation delay between the UE and the base station, a duration of a transmission time interval associated with transmission of a contention resolution identifier, or a gap between downlink data channel reception and uplink control channel transmission, or a combination thereof. In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, transmitting acknowledgment information may include operations, features, means, or instructions for transmitting acknowledgment information based on elapse of a contention resolution window, the acknowledgment information including a negative acknowledgment.

[0040] A method for wireless communication at a base station is described. The method may include receiving a random access message associated with a random access procedure from a UE; and transmitting a configuration for a contention resolution timer. The method may further include transmitting, during a contention resolution window associated with the random access procedure, a first downlink data channel transmission from a set of multiple downlink data channel transmissions associated with the random access procedure based on the configuration for the contention resolution timer, the first downlink data channel transmission carrying a contention resolution MAC-CE. The method may further include receiving an acknowledgment regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0041] An apparatus for wireless communication at a base station is described. The apparatus may include a processor; and a memory coupled to the processor, the processor and the memory being configured to: receive a random access message associated with a random access procedure from a UE; and transmit a configuration regarding a contention resolution timer. The processor and the memory may be further configured to transmit, during a contention resolution window associated with the random access procedure, a first downlink data channel transmission from a set of multiple downlink data channel transmissions associated with the random access procedure, the first downlink data channel transmission carrying a contention resolution MAC-CE based on the configuration regarding the contention resolution timer. The processor and the memory may be further configured to receive acknowledgment information regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0042] Another apparatus for wireless communication at a base station is described. The apparatus may include means for receiving a random access message associated with a random access procedure from a UE; and means for transmitting a configuration regarding a contention resolution timer. The apparatus may further include means for transmitting, during a contention resolution window associated with the random access procedure, a first downlink data channel transmission from a set of multiple downlink data channel transmissions associated with the random access procedure based on transmitting the configuration regarding the contention resolution timer, the first downlink data channel transmission carrying a contention resolution MAC-CE. The apparatus may further include means for receiving an acknowledgment regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0043] A non-transitory computer-readable medium storing code for wireless communication at a base station is described. The code may include instructions executable by a processor to: receive a random access message associated with a random access procedure from a UE; and transmit a configuration regarding a contention resolution timer. The code may further include instructions executable by the processor to: transmit a first downlink data channel transmission from a set of multiple downlink data channel transmissions associated with the random access procedure during a contention resolution window associated with the random access procedure based on the configuration regarding the contention resolution timer, the first downlink data channel transmission carrying a contention resolution MAC-CE. The code may further include instructions executable by the processor to: receive acknowledgment information regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0044] Some examples of the methods, devices, and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for: transmitting a DCI message that schedules a second downlink data channel transmission carrying a second contention resolution MAC-CE in a set of multiple downlink data channel transmissions. In some examples of the methods, devices, and non-transitory computer-readable media described herein, the DCI message includes an indication to disable HARQ feedback for the second downlink data channel transmission.

[0045] A method for wireless communication at a user equipment terminal (UE) is described. The method may include transmitting a random access message associated with a random access procedure to a base station, wherein HARQ feedback is disabled for the random access procedure. The method may further include monitoring a contention resolution window associated with the random access procedure for a first downlink data channel transmission associated with the random access procedure in a set of downlink data channel transmissions, the first downlink data channel transmission carrying a contention resolution MAC-CE. The method may further include transmitting, based on an indication that HARQ feedback is to be enabled, an acknowledgment regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0046] An apparatus for wireless communication is described. The apparatus may include a processor; and a memory coupled to the processor, the processor and the memory being configured to transmit a random access message associated with a random access procedure to a base station, wherein HARQ feedback is disabled for the random access procedure. The processor and the memory may be further configured to monitor a contention resolution window associated with the random access procedure for a first downlink data channel transmission associated with the random access procedure in a set of downlink data channel transmissions, the first downlink data channel transmission carrying a contention resolution MAC-CE. The processor and the memory may be further configured to transmit, based on an indication that HARQ feedback is to be enabled, an acknowledgment of the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0047] Another apparatus for wireless communication is described. The apparatus may include means for transmitting a random access message associated with a random access procedure to a base station, wherein HARQ feedback is disabled for the random access procedure. The apparatus may further include means for monitoring a contention resolution window associated with the random access procedure for a first downlink data channel transmission associated with the random access procedure in a set of downlink data channel transmissions, the first downlink data channel transmission carrying a contention resolution MAC-CE. The apparatus may further include means for transmitting, based on an indication that HARQ feedback is to be enabled, an acknowledgment regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0048] A non-transitory computer-readable medium storing code for wireless communication at a UE is described. The code may include instructions executable by a processor to transmit a random access message associated with a random access procedure to a base station, wherein HARQ feedback is disabled for the random access procedure. The code may further include instructions executable by the processor to monitor a contention resolution window associated with the random access procedure for a first downlink data channel transmission associated with the random access procedure in a set of downlink data channel transmissions, the first downlink data channel transmission carrying a contention resolution MAC-CE. The code may further include instructions executable by the processor to transmit, based on an indication that HARQ feedback is to be enabled, an acknowledgment regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0049] In some examples of the methods, devices, and non-transitory computer-readable media described herein, the random access message includes msg3. Some examples of the methods, devices, and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for: identifying, in the UE context information, an indication that HARQ feedback is to be enabled; and enabling HARQ feedback based on the indication.

[0050] Some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for the following actions: transmitting, in the random access message, a request to enable HARQ feedback for the first downlink data channel transmission carrying the contention resolution MAC-CE. Some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for the following actions: receiving an indication in a contention resolution MAC-CE; and enabling HARQ feedback based on the indication in the contention resolution MAC-CE.

[0051] In some examples of the methods, devices, and non-transitory computer-readable media described herein, the indication includes a bit indication. In some examples of the methods, devices, and non-transitory computer-readable media described herein, the bit indication includes a reserved bit in a MAC subheader of a contention resolution MAC-CE.

[0052] Some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for: receiving a downlink control information (DCI) message that schedules a first downlink data channel transmission carrying the contention resolution MAC-CE, the DCI message including an indication that HARQ feedback is to be enabled.

[0053] Some examples of the methods, devices (apparatuses), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for the following actions: determining resources associated with an uplink control channel based on a second indication in a contention resolution MAC-CE. In some examples of the methods, devices (apparatuses), and non-transitory computer-readable media described herein, transmitting an acknowledgment includes transmitting an acknowledgment on an uplink control channel using the determined resources. In some examples of the methods, devices (apparatuses), and non-transitory computer-readable media described herein, the second indication includes a new MAC-CE providing uplink control channel resources. In some examples of the methods, devices (apparatuses), and non-transitory computer-readable media described herein, the logical channel identifier of the MAC-CE may be the same as or different from the contention resolution MAC-CE. In some examples of the methods, devices (apparatuses), and non-transitory computer-readable media described herein, the resources may be adjacent to the end of the contention resolution window.

[0054] Some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for: receiving a DCI message that schedules resources associated with an uplink control channel. In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, transmitting an acknowledgment includes transmitting the acknowledgment on the uplink control channel using the scheduled resources.

[0055] Some examples of the methods, devices, and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for determining the scheduled resources based on one or more resource indexes in the DCI message. In some examples of the methods, devices, and non-transitory computer-readable media described herein, the one or more resource indexes correspond to the scheduled resources.

[0056] Some examples of the methods, devices, and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for determining a reception failure of a first downlink data channel transmission carrying a contention resolution MAC-CE. In some examples of the methods, devices, and non-transitory computer-readable media described herein, HARQ feedback may be enabled for a random access procedure. In some examples of the methods, devices, and non-transitory computer-readable media described herein, the acknowledgment information includes a negative acknowledgment.

[0057] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, transmitting acknowledgment information may include operations, features, means, or instructions for transmitting acknowledgment information based on elapse of a contention resolution window. In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, HARQ feedback may be enabled for a random access procedure, and the acknowledgment information may include a negative acknowledgment.

[0058] Some examples of the methods, devices (apparatuses), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for: receiving a configuration regarding a contention resolution timer; and setting a value of the contention resolution timer based on the configuration.

[0059] In some examples of the methods, devices, and non-transitory computer-readable media described herein, the value of the contention resolution timer can be based on one or more of: a maximum propagation delay between the UE and the base station, a duration of a transmission time interval associated with transmission of a contention resolution identifier, or a gap between downlink data channel reception and uplink control channel transmission, or a combination thereof.

[0060] In some examples of the methods, devices, and non-transitory computer-readable media described herein, the contention resolution window includes one or more discontinuous reception (DRX) cycles. In some examples of the methods, devices, and non-transitory computer-readable media described herein, monitoring the contention resolution window may include operations, features, means, or instructions for monitoring the contention resolution window during one or more active durations associated with the one or more DRX cycles.

[0061] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, the base station may be a non-terrestrial base station including a satellite or a high-altitude platform station in a non-terrestrial network.

[0062] In some examples of the methods, devices, and non-transitory computer-readable media described herein, the acknowledgment information includes a positive acknowledgment or a negative acknowledgment. In some examples of the methods, devices, and non-transitory computer-readable media described herein, the contention resolution MAC-CE includes a contention resolution identifier. In some examples of the methods, devices, and non-transitory computer-readable media described herein, the length of the contention resolution identifier in the contention resolution MAC-CE may be less than or equal to a default length of the default contention resolution identifier.

[0063] Some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for transmitting an RRC message indicating a failure of contention resolution associated with a random access procedure.

[0064] A method for wireless communication at a base station is described. The method may include receiving a random access message associated with a random access procedure from a UE, wherein HARQ feedback is disabled for the random access procedure. The method may further include determining a contention resolution window associated with the random access procedure for a first downlink data channel transmission associated with the random access procedure in a set of downlink data channel transmissions, the first downlink data channel transmission carrying a contention resolution MAC-CE. The method may further include receiving an acknowledgment regarding the first downlink data channel transmission carrying the contention resolution MAC-CE based on transmitting an indication to the UE that HARQ feedback is to be enabled.

[0065] An apparatus for wireless communication is described. The apparatus may include a processor; and a memory coupled to the processor, the processor and the memory being configured to receive a random access message associated with a random access procedure from a UE, wherein HARQ feedback is disabled for the random access procedure. The processor and the memory may be further configured to determine a contention resolution window associated with the random access procedure for a first downlink data channel transmission associated with the random access procedure in a downlink data channel transmission set, the first downlink data channel transmission carrying a contention resolution MAC-CE. The processor and the memory may be further configured to receive acknowledgment information regarding the first downlink data channel transmission carrying the contention resolution MAC-CE based on transmitting an indication to the UE that HARQ feedback is to be enabled.

[0066] Another apparatus for wireless communication is described. The apparatus may include means for receiving, from a UE, a random access message associated with a random access procedure, wherein HARQ feedback is disabled for the random access procedure. The apparatus may further include means for determining a contention resolution window associated with the random access procedure for a first downlink data channel transmission associated with the random access procedure in a set of downlink data channel transmissions, the first downlink data channel transmission carrying a contention resolution MAC-CE. The apparatus may further include means for receiving, based on transmitting an indication to the UE that HARQ feedback is to be enabled, an acknowledgment regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0067] A non-transitory computer-readable medium storing code for wireless communication at a base station is described. The code may include instructions executable by a processor to: receive a random access message associated with a random access procedure from a UE, wherein HARQ feedback is disabled for the random access procedure. The code may further include instructions executable by the processor to: determine a contention resolution window associated with the random access procedure for a first downlink data channel transmission associated with the random access procedure in a set of downlink data channel transmissions, the first downlink data channel transmission carrying a contention resolution MAC-CE. The code may further include instructions executable by the processor to: receive an acknowledgment regarding the first downlink data channel transmission carrying the contention resolution MAC-CE based on transmitting an indication to the UE that HARQ feedback is to be enabled.

[0068] In some examples of the methods, devices, and non-transitory computer-readable media described herein, the random access message includes msg3. Some examples of the methods, devices, and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for the following actions: including the indication in the UE context information.

[0069] Some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for: receiving, in the random access message, a request to enable HARQ feedback for the first downlink data channel transmission carrying the contention resolution MAC-CE. Some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for: transmitting an indication in a contention resolution MAC-CE.

[0070] In some examples of the methods, devices, and non-transitory computer-readable media described herein, the indication includes a bit indication. In some examples of the methods, devices, and non-transitory computer-readable media described herein, the bit indication includes a reserved bit in a MAC-CE of a contention resolution MAC-CE.

[0071] Some examples of the methods, devices, and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for transmitting a DCI message scheduling a first downlink data channel transmission carrying a contention resolution MAC-CE. In some examples of the methods, devices, and non-transitory computer-readable media described herein, the DCI message includes an indication that HARQ feedback is to be enabled.

[0072] Some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for transmitting a DCI message that schedules resources associated with an uplink control channel. In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, receiving the acknowledgment information includes receiving the acknowledgment information on the uplink control channel using the scheduled resources.

[0073] In some examples of the methods, devices, and non-transitory computer-readable media described herein, receiving an acknowledgment may include operations, features, means, or instructions for receiving an acknowledgment based on the elapse of a contention resolution window. In some examples of the methods, devices, and non-transitory computer-readable media described herein, the acknowledgment includes a negative acknowledgment.

[0074] In some examples of the methods, devices, and non-transitory computer-readable media described herein, the contention resolution window includes one or more DRX cycles. In some examples of the methods, devices, and non-transitory computer-readable media described herein, the base station may be a non-terrestrial base station including a satellite or a high-altitude platform station in a non-terrestrial network.

[0075] In some examples of the methods, devices, and non-transitory computer-readable media described herein, the acknowledgment information includes a positive acknowledgment or a negative acknowledgment. In some examples of the methods, devices, and non-transitory computer-readable media described herein, the contention resolution MAC-CE includes a contention resolution identifier. Some examples of the methods, devices, and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for receiving an RRC message indicating a failure of contention resolution associated with a random access procedure.

[0076] A method for wireless communication at a user equipment terminal (UE) is described. The method may include transmitting a random access message associated with a random access procedure to a base station, wherein HARQ feedback is disabled for the random access procedure. The method may further include monitoring a contention resolution window associated with the random access procedure for a downlink data channel transmission carrying a contention resolution MAC-CE. The method may further include refraining from transmitting an acknowledgment regarding a downlink data channel transmission carrying a random access response message including a contention resolution MAC-CE based on the disabled HARQ feedback.

[0077] An apparatus for wireless communication is described. The apparatus may include a processor; and a memory coupled to the processor, the processor and the memory being configured to transmit a random access message associated with a random access procedure to a base station, wherein HARQ feedback is disabled for the random access procedure. The processor and the memory may be further configured to monitor a contention resolution window associated with the random access procedure for a downlink data channel transmission carrying a contention resolution MAC-CE. The processor and the memory may be further configured to refrain from transmitting acknowledgment information regarding a downlink data channel transmission carrying a random access response message including a contention resolution MAC-CE based on the disabled HARQ feedback.

[0078] Another apparatus for wireless communication is described. The apparatus may include means for transmitting a random access message associated with a random access procedure to a base station, wherein HARQ feedback is disabled for the random access procedure. The apparatus may further include means for monitoring a contention resolution window associated with the random access procedure for a downlink data channel transmission carrying a contention resolution MAC-CE. The apparatus may further include means for refraining from transmitting acknowledgment information regarding a downlink data channel transmission carrying a random access response message including a contention resolution MAC-CE based on the disabled HARQ feedback.

[0079] A non-transitory computer-readable medium storing code for wireless communication at a UE is described. The code may include instructions executable by a processor to transmit a random access message associated with a random access procedure to a base station, wherein HARQ feedback is disabled for the random access procedure. The code may further include instructions executable by the processor to monitor a contention resolution window associated with the random access procedure for a downlink data channel transmission carrying a contention resolution MAC-CE. The code may further include instructions executable by the processor to refrain from transmitting an acknowledgment regarding a downlink data channel transmission carrying a random access response message including a contention resolution MAC-CE based on the disabled HARQ feedback.

[0080] In some examples of the methods, devices, and non-transitory computer-readable media described herein, the random access message includes msg3. In some examples of the methods, devices, and non-transitory computer-readable media described herein, monitoring a contention resolution window associated with a random access procedure may include operations, features, means, or instructions for monitoring the contention resolution window for a number of repetitions associated with a downlink data channel transmission carrying the contention resolution MAC-CE.

[0081] Some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for the following actions: receiving a configuration including an indication of a number of repetitions associated with a downlink data channel transmission carrying the contention resolution MAC-CE. Some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for the following actions: receiving a downlink control channel carrying a DCI message that schedules one or more transport blocks associated with the number of repetitions associated with the downlink data channel transmission carrying the contention resolution MAC-CE.

[0082] Some examples of the methods, devices, and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for: receiving a configuration regarding a contention resolution timer; and setting a value for the contention resolution timer based on the configuration. In some examples of the methods, devices, and non-transitory computer-readable media described herein, the value of the contention resolution timer may be based on one or more of the following: a maximum propagation delay between the UE and the base station, a duration of a transmission time interval associated with transmission of a contention resolution identifier, or a gap between downlink data channel reception and uplink control channel transmission, or a combination thereof.

[0083] Some examples of the methods, devices, and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for starting a contention resolution timer associated with the contention resolution window, wherein monitoring the contention resolution window may be based on the contention resolution timer.

[0084] In some examples of the methods, devices, and non-transitory computer-readable media described herein, the contention resolution window includes one or more DRX cycles. In some examples of the methods, devices, and non-transitory computer-readable media described herein, monitoring the contention resolution window may include operations, features, means, or instructions for monitoring the contention resolution window during one or more active durations associated with the one or more DRX cycles.

[0085] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, the base station may be a non-terrestrial base station including a satellite or a high-altitude platform station in a non-terrestrial network.

[0086] A method for wireless communication at a base station is described. The method may include receiving a random access message associated with a random access procedure from a UE, wherein HARQ feedback is disabled for the random access procedure; and determining a contention resolution window associated with the random access procedure for use in a downlink data channel transmission carrying a contention resolution MAC-CE. The method may further include refraining from receiving acknowledgment information regarding a downlink data channel transmission carrying a random access response message including a contention resolution MAC-CE based on the disabled HARQ feedback.

[0087] An apparatus for wireless communication is described. The apparatus may include a processor; and a memory coupled to the processor, the processor and the memory configured to: receive a random access message associated with a random access procedure from a UE, wherein HARQ feedback is disabled for the random access procedure; and determine a contention resolution window associated with the random access procedure for a downlink data channel transmission carrying a contention resolution MAC-CE. The processor and the memory may be further configured to: refrain from receiving acknowledgment information regarding a downlink data channel transmission carrying a random access response message including a contention resolution MAC-CE based on the disabled HARQ feedback.

[0088] Another apparatus for wireless communication is described. The apparatus may include means for receiving a random access message associated with a random access procedure from a UE, wherein HARQ feedback is disabled for the random access procedure; and determining a contention resolution window associated with the random access procedure for use in downlink data channel transmissions carrying a contention resolution MAC-CE. The apparatus may further include means for refraining from receiving acknowledgment information regarding a downlink data channel transmission carrying a random access response message including a contention resolution MAC-CE based on the disabled HARQ feedback.

[0089] A non-transitory computer-readable medium storing code for wireless communication at a base station is described. The code may include instructions executable by a processor to: receive a random access message associated with a random access procedure from a UE, wherein HARQ feedback is disabled for the random access procedure; and determine a contention resolution window associated with the random access procedure for a downlink data channel transmission carrying a contention resolution MAC-CE. The code may further include instructions executable by the processor to: refrain from receiving acknowledgment information regarding a downlink data channel transmission carrying a random access response message including a contention resolution MAC-CE based on the disabled HARQ feedback.

[0090] In some examples of the methods, devices, and non-transitory computer-readable media described herein, the random access message includes msg3. Some examples of the methods, devices, and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for: transmitting a configuration including an indication of a number of repetitions associated with a downlink data channel transmission carrying the contention resolution MAC-CE.

[0091] Some examples of the methods, devices, and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for transmitting a downlink control channel carrying a DCI message that schedules one or more transport blocks associated with a repetition number of downlink data channel transmissions associated with the contention resolution MAC-CE. In some examples of the methods, devices, and non-transitory computer-readable media described herein, the contention resolution window includes one or more DRX cycles.

[0092] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, the base station may be a non-terrestrial base station including a satellite or a high-altitude platform station in a non-terrestrial network.

[0093] A method for wireless communication at a UE is described. The method may include transmitting a random access message associated with a random access procedure to a base station; and determining that HARQ feedback is disabled for the random access procedure. The method may further include refraining from transmitting acknowledgment information regarding a downlink data channel transmission carrying a random access response message including one or more of a contention resolution MAC-CE, an SDU associated with a downlink shared control channel, or both, based on the disabled HARQ feedback.

[0094] An apparatus for wireless communication is described. The apparatus may include a processor and a memory coupled to the processor, the processor and the memory configured to: transmit a random access message associated with a random access procedure to a base station; and determine that HARQ feedback is disabled for the random access procedure. The processor and the memory may be further configured to: refrain from transmitting acknowledgment information regarding a downlink data channel transmission carrying a random access response message including one or more of a contention resolution MAC-CE, an SDU associated with a downlink shared control channel, or both, based on the disabled HARQ feedback.

[0095] Another apparatus for wireless communication is described. The apparatus may include means for transmitting a random access message associated with a random access procedure to a base station; and determining that HARQ feedback is disabled for the random access procedure. The apparatus may further include means for refraining from transmitting acknowledgment information regarding a downlink data channel transmission carrying a random access response message including one or more of a contention resolution MAC-CE, an SDU associated with a downlink shared control channel, or both, based on the disabled HARQ feedback.

[0096] A non-transitory computer-readable medium storing code for wireless communication at a UE is described. The code may include instructions executable by a processor to: transmit a random access message associated with a random access procedure to a base station; and determine that HARQ feedback is disabled for the random access procedure. The code may further include instructions executable by the processor to: refrain from transmitting acknowledgment information regarding a downlink data channel transmission carrying a random access response message including one or more of a contention resolution MAC-CE, an SDU associated with a downlink shared control channel, or both, based on the disabled HARQ feedback.

[0097] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, the random access message includes msg3. Some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for: monitoring a contention resolution window associated with a random access procedure for a downlink data channel transmission carrying a random access response message including one or more of a contention resolution MAC-CE or an SDU associated with a downlink shared control channel, or both.

[0098] Some examples of the methods, devices (apparatuses), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for the following actions: receiving a configuration regarding a contention resolution timer; and setting a value of the contention resolution timer based on the configuration. In some examples of the methods, devices (apparatuses), and non-transitory computer-readable media described herein, the value of the contention resolution timer may be based on one or more of the following: a maximum propagation delay between the UE and the base station, a duration of a transmission time interval associated with the transmission of a contention resolution identifier, or a gap between downlink data channel reception and uplink control channel transmission, or a combination thereof. Some examples of the methods, devices (apparatuses), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for the following actions: starting a contention resolution timer associated with the contention resolution window, wherein monitoring the contention resolution window may be based on the contention resolution timer.

[0099] In some examples of the methods, devices, and non-transitory computer-readable media described herein, the contention resolution window includes one or more DRX cycles. In some examples of the methods, devices, and non-transitory computer-readable media described herein, monitoring the contention resolution window may include operations, features, means, or instructions for monitoring the contention resolution window during one or more active durations associated with the one or more DRX cycles.

[0100] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, the base station may be a non-terrestrial base station including a satellite or a high-altitude platform station in a non-terrestrial network.

[0101] A method of wireless communication at a UE is described. The method may include transmitting a random access message associated with a random access procedure to a base station; and receiving a random access response message associated with the random access procedure, the random access response message including a timing advance. The method may further include determining that HARQ feedback is disabled for the random access procedure; and controlling an uplink alignment timer based on the timing advance, the disabled HARQ feedback, or both.

[0102] An apparatus for wireless communication is described. The apparatus may include a processor and a memory coupled to the processor, the processor and the memory configured to: transmit a random access message associated with a random access procedure to a base station; and receive a random access response message associated with the random access procedure, the random access response message including a timing advance. The processor and the memory may be further configured to: determine that HARQ feedback is disabled for the random access procedure; and control an uplink alignment timer based on the timing advance, the disabled HARQ feedback, or both.

[0103] Another apparatus for wireless communication is described. The apparatus may include means for transmitting a random access message associated with a random access procedure to a base station; and receiving a random access response message associated with the random access procedure, the random access response message including a timing advance. The apparatus may further include means for determining that HARQ feedback is disabled for the random access procedure; and controlling an uplink alignment timer based on the timing advance, the disabled HARQ feedback, or both.

[0104] A non-transitory computer-readable medium storing code for wireless communication at a UE is described. The code may include instructions executable by a processor to: transmit a random access message associated with a random access procedure to a base station; and receive a random access response message associated with the random access procedure, the random access response message including a timing advance. The code may further include instructions executable by the processor to: determine that HARQ feedback is disabled for the random access procedure; and control an uplink alignment timer based on the timing advance, the disabled HARQ feedback, or both.

[0105] In some examples of the methods, devices, and non-transitory computer-readable media described herein, the random access message includes msg3. Some examples of the methods, devices, and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for setting an uplink alignment timer based on a configuration. Some examples of the methods, devices, and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for activating an uplink alignment timer based on receiving a random access response message including a timing advance.

[0106] Some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for: deactivating an uplink alignment timer based on receiving a contention resolution MAC-CE and before transmitting an acknowledgment of a downlink data channel transmission carrying the contention resolution MAC-CE, or both. In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, a value for the uplink alignment timer may be based on one or more of: a maximum propagation delay between the UE and the base station, a duration of a transmission time interval, or a gap between downlink data channel reception and uplink control channel transmission, or a combination thereof.

[0107] A method for wireless communication at a user equipment terminal (UE) is described. The method may include transmitting a random access message associated with a random access procedure to a base station; and monitoring a contention resolution window associated with the random access procedure for a first downlink data channel transmission associated with the random access procedure in a set of downlink data channel transmissions, the first downlink data channel transmission carrying a contention resolution MAC-CE. The method may further include transmitting an acknowledgment regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0108] An apparatus for wireless communication is described. The apparatus may include a processor and a memory coupled to the processor, the processor and the memory being configured to: transmit a random access message associated with a random access procedure to a base station; and monitor a contention resolution window associated with the random access procedure for a first downlink data channel transmission associated with the random access procedure in a set of downlink data channel transmissions, the first downlink data channel transmission carrying a contention resolution MAC-CE. The processor and the memory may be further configured to transmit an acknowledgment regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0109] Another apparatus for wireless communication is described. The apparatus may include: means for transmitting a random access message associated with a random access procedure to a base station; and means for monitoring a contention resolution window associated with the random access procedure for a first downlink data channel transmission associated with the random access procedure in a set of downlink data channel transmissions, the first downlink data channel transmission carrying a contention resolution MAC-CE. The apparatus may further include means for transmitting an acknowledgment regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0110] A non-transitory computer-readable medium storing code for wireless communication at a UE is described. The code may include instructions executable by a processor to: transmit a random access message associated with a random access procedure to a base station; and monitor a contention resolution window associated with the random access procedure for a first downlink data channel transmission associated with the random access procedure in a set of downlink data channel transmissions, the first downlink data channel transmission carrying a contention resolution MAC-CE. The code may further include instructions executable by the processor to: transmit an acknowledgment regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0111] In some examples of the methods, devices, and non-transitory computer-readable media described herein, the random access message includes msg3. Some examples of the methods, devices, and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for determining to transmit an acknowledgment regarding the first downlink data channel transmission carrying the contention resolution MAC-CE. In some examples of the methods, devices, and non-transitory computer-readable media described herein, transmitting the acknowledgment regarding the first downlink data channel transmission carrying the contention resolution MAC-CE may be based on the determination.

[0112] In some examples of the methods, devices, and non-transitory computer-readable media described herein, transmitting an acknowledgment may include operations, features, means, or instructions for transmitting an acknowledgment based on the elapse of a contention resolution window, the acknowledgment including a negative acknowledgment. Some examples of the methods, devices, and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for receiving a configuration regarding a contention resolution timer and setting a value for the contention resolution timer based on the configuration.

[0113] In some examples of the methods, devices, and non-transitory computer-readable media described herein, the contention resolution window includes one or more DRX cycles. In some examples of the methods, devices, and non-transitory computer-readable media described herein, monitoring the contention resolution window may include operations, features, means, or instructions for monitoring the contention resolution window during one or more active durations associated with the one or more DRX cycles. BRIEF DESCRIPTION OF THE DRAWINGS

[0115] Figure 1 and 2

[0014] An example of a wireless communication system in accordance with one or more aspects of the present disclosure is illustrated.

[0116] Figure 3 and 4 Illustrated are examples of transmission timelines in accordance with one or more aspects of the present disclosure.

[0117] Figure 5 and 6 A block diagram of a device according to one or more aspects of the present disclosure is shown.

[0118] Figure 7 A block diagram of a UE communications manager is shown in accordance with one or more aspects of the present disclosure.

[0119] Figure 8 A diagram illustrating a system including a device according to one or more aspects of the present disclosure is shown.

[0120] Figure 9 and 10 A block diagram of a device according to one or more aspects of the present disclosure is shown.

[0121] Figure 11 A block diagram of a base station communications manager is shown in accordance with one or more aspects of the present disclosure.

[0122] Figure 12 A diagram illustrating a system including a device according to one or more aspects of the present disclosure is shown.

[0123] Figures 13 to 24A flowchart illustrating a method according to one or more aspects of the present disclosure is shown.

[0124] Detailed description

[0125] A communication system may include multiple communication devices, such as UEs and base stations (which may provide communication services to the UEs). For example, such base stations may be next-generation B nodes or gigabit B nodes (either of which may be referred to as gNBs) that may support multiple radio access technologies, including fourth-generation (4G) systems (such as long-term evolution (LTE) systems) and fifth-generation (5G) systems (which may be referred to as new radio (NR) systems). Some communication systems (such as 4G and 5G systems) may support various random access procedures (such as two-step or four-step random access procedures). These random access procedures may also be contention-based or contention-free. Some communication systems (such as 4G and 5G systems) may support efficient contention resolution operations for contention-based random access procedures by, for example, reducing latency associated with contention resolution operations. For example, some communication systems, such as non-terrestrial communication systems (e.g., low Earth orbit (LEO) communication systems, medium Earth orbit (MEO) communication systems, geosynchronous equatorial orbit (GEO) communication systems), may experience improvements to random access procedures by supporting early contention resolution operations, as described herein.

[0126] As an example, as part of a four-step random access procedure, the base station and the UE may exchange one or more random access messages (e.g., handshake messages), such as random access message 1 (msg1), random access message 2 (msg2), msg3, and random access message 4 (msg4). In this example, the random access procedure may be contention-based. In order to reduce the latency associated with the contention-based portion of the random access procedure, the base station may perform early contention resolution operations. The base station may perform early contention resolution operations with the UE after receiving msg3 during the random access procedure. In some examples, the contention resolution operations may correspond to a contention resolution window, which may be related to a contention resolution timer. For example, the contention resolution window may correspond to a time during which the UE may perform contention resolution operations and may end when the contention resolution timer expires.

[0127] Therefore, the base station can perform an early contention resolution operation (i.e., attempt to resolve contention) while suspending the transmission of msg4 to the UE. As part of the early contention resolution operation, the base station can transmit a contention resolution MAC-CE without transmitting msg4. The contention resolution MAC-CE may include a contention resolution identifier, which the UE can use to declare that the random access procedure is successful or unsuccessful. For example, the UE can receive the contention resolution identifier and compare it with an identifier specific to the UE (e.g., a radio network temporary identifier (C-RNTI) that varies from cell to cell). When the identifiers match, the UE can declare that the random access procedure is successful. Otherwise, if there is no match between the identifiers, the UE is deemed to have failed the random access procedure and can repeat the random access procedure with the base station.

[0128] By supporting early contention resolution, as described above, some communication systems, such as non-terrestrial communication systems (e.g., LEO, MEO, GEO, and GEO communication systems), can experience improvements to the random access procedure by supporting early contention resolution. For example, the base station may be a non-terrestrial base station (e.g., a satellite, a high-altitude platform station, etc.) and, as a result of the early contention resolution, may have additional time to prepare the RRC configuration to be transmitted in MSG4. In some examples, the base station may include a control unit (CU) (e.g., a gNB-CU) and a distributed unit (DU) (e.g., a gNB-DU). The gNB-CU may be non-terrestrial, while the gNB-DU may be terrestrial (i.e., located on the ground). Alternatively, in some examples, the gNB-CU may be terrestrial, while the gNB-DU may be non-terrestrial. As such, there may be a latency between the gNB-DU and the gNB-CU. For example, the gNB-DU may have to wait for the RRC configuration from the gNB-CU. The gNB-DU may transmit a contention resolution MAC-CE to the UE while waiting to receive the RRC configuration from the gNB-CU.

[0129] In some examples, the UE may be configured to disable HARQ feedback for a random access procedure. As a result, in such examples, the base station may not know whether the UE has received a contention resolution MAC-CE (including a contention resolution identifier) and whether the UE has determined whether the random access procedure is successful or failed. In some cases, HARQ feedback may be enabled only for the first physical downlink shared channel (PDSCH) carrying the contention resolution MAC-CE. Otherwise, HARQ feedback may be disabled for all other PDSCHs. This may be hard-coded (e.g., by default) or may be indicated via an indication, as described herein. Various aspects of the described technology relate to configuring a base station and a UE to support flexible HARQ feedback to provide efficient contention resolution operation for a contention-based random access procedure. For example, the base station and the UE may be configured to support reduced latency associated with contention resolution operation when HARQ feedback is disabled or enabled based in part on a trigger (e.g., a transmitted or received indication that HARQ feedback is to be enabled, etc.).

[0130] When operating in a 5G system (including non-terrestrial communication systems), operations performed by the UE can provide higher reliability and lower latency for communications. In some examples, configuring the UE to support flexible HARQ feedback for random access procedures and other examples in 5G systems can support benefits such as reduced power consumption, coverage enhancement, and increased resource utilization, spectrum efficiency, data rate, and capacity.

[0131] Aspects of the present disclosure are initially described in the context of a communication system. Aspects of the present disclosure are further illustrated and described by and with reference to transmission timelines and process flows related to contention resolution for a contention-based random access procedure. Aspects of the present disclosure are further illustrated and described by and with reference to apparatus diagrams, system diagrams, and flow diagrams related to contention resolution for a contention-based random access procedure.

[0132] Figure 1 An example of a wireless communication system 100 according to one or more aspects of the present disclosure is illustrated. The wireless communication 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 communication system 100 may be a Long Term Evolution (LTE) network, an Advanced LTE (LTE-A) network, an LTE-A Pro network, or a New Radio (NR) network. In some examples, the wireless communication system 100 may support enhanced broadband communication, ultra-reliable (e.g., mission-critical) communication, low-latency communication, communication with low-cost and low-complexity devices, or any combination thereof.

[0133] Base stations 105 may be dispersed throughout a geographic area to form wireless communication system 100 and may be different forms of devices or devices with different capabilities. Base stations 105 and UEs 115 may communicate wirelessly via one or more communication links 125. Each base station 105 may provide a coverage area 110 over which UEs 115 and base stations 105 may establish one or more communication links 125. Coverage area 110 may be an example of a geographic area over which base stations 105 and UEs 115 may support signal communication according to one or more radio access technologies.

[0134] The UEs 115 may be dispersed throughout the coverage area 110 of the wireless communication system 100, and each UE 115 may be stationary or mobile, or stationary and mobile at different times. The UEs 115 may be different forms of devices or devices with different capabilities. Figure 1 1. The UE 115 described herein may be capable of communicating with various types of devices, such as other UEs 115, base stations 105, or network equipment (e.g., core network nodes, relays, integrated access and backhaul (IAB) nodes, or other network equipment), such as Figure 1 As shown in .

[0135] Each base station 105 can communicate with the core network 130, with each other, or both. For example, the base stations 105 can interface with the core network 130 via one or more backhaul links 120 (e.g., via S1, N2, N3, or other interfaces). The base stations 105 can communicate with each other directly (e.g., directly between the base stations 105), indirectly (e.g., via the core network 130), or both directly and indirectly over the backhaul links 120 (e.g., via X2, Xn, or other interfaces). In some examples, the backhaul links 120 can be or include one or more wireless links. One or more of the base stations 105 described herein may include or may be referred to by one of ordinary skill in the art as a base transceiver station, a radio base station, an access point, a radio transceiver, a Node B, an evolved Node B (eNB), a next generation Node B, or a Gigabit Node B (any of which may be referred to as a gNB), a Home Node B, a Home evolved Node B, or other suitable terminology. The UE 115 can communicate with the core network 130 via a communication link 155.

[0136] The 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 term, where "device" may also be referred to as a unit, a station, a terminal, or a client, etc. The 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, the UE 115 may include or be referred to as a wireless local loop (WLL) station, an Internet of Things (IoT) device, an Internet of Everything (IoE) device, or a machine type communication (MTC) device, etc., which may be implemented in various objects such as appliances or vehicles, meters, etc. The UE 115 described herein may be capable of communicating with various types of devices, such as other UEs 115, which may sometimes act as relays, as well as base stations 105 and network equipment including macro eNBs or gNBs, small cell eNBs or gNBs, relay base stations, etc. Figure 1 As shown in .

[0137] The UE 115 and the base station 105 may communicate wirelessly with each other via one or more communication links 125 on 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 link 125. For example, a carrier for the communication link 125 may include a portion of a radio frequency spectrum band (e.g., a bandwidth portion (BWP)) that operates 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 for coordinating carrier operation, user data, or other signaling. The wireless communication system 100 may support communication with the UE 115 using carrier aggregation or multi-carrier operation. The 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 duplex (FDD) and time division duplex (TDD) component carriers.

[0138] In some examples (e.g., in a carrier aggregation configuration), a carrier may also have acquisition signaling or control signaling that coordinates the operation of other carriers. A carrier may be associated with a frequency channel (e.g., an Evolved Universal Mobile Telecommunications System Terrestrial Radio Access (E-UTRA) Absolute Radio Frequency Channel Number (EARFCN)) and may be located according to a channel grid for discovery by a UE 115. A carrier may operate in a standalone mode in which initial acquisition and connection may be performed by a UE 115 via the carrier, or a carrier may operate in a non-standalone mode in which the connection is anchored using a different carrier (e.g., a different carrier of the same or different radio access technology). The communication link 125 shown in the wireless communication system 100 may include an uplink transmission from a UE 115 to a base station 105, or a downlink transmission from a base station 105 to a UE 115. A carrier may carry downlink or uplink communications (e.g., in FDD mode), or may be configured to carry downlink and uplink communications (e.g., in TDD mode).

[0139] A carrier may be associated with a particular bandwidth of radio frequency spectrum, and in some examples, the carrier bandwidth may be referred to as the "system bandwidth" of the carrier or wireless communication system 100. For example, the carrier bandwidth may be one of several determined bandwidths (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 megahertz (MHz)) of a carrier of a particular radio access technology. Devices of the wireless communication system 100 (e.g., base station 105, UE 115, or both) may have a hardware configuration that supports communication on a particular carrier bandwidth, or may be configurable to support communication on one of a set of carrier bandwidths. In some examples, the wireless communication system 100 may include a base station 105 or UE 115 that supports simultaneous communication via carriers associated with multiple carrier bandwidths. In some examples, each served UE 115 may be configured to operate on a portion (e.g., a subband, a BWP) or all of the carrier bandwidth.

[0140] The signal waveform transmitted on the carrier may include multiple subcarriers (e.g., using a multicarrier modulation (MCM) technique 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 include one symbol period (e.g., the 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 code rate of the modulation scheme, or both). Thus, the more resource elements received by UE 115 and the higher the order of the modulation scheme, the higher the data rate of UE 115 can be. Wireless communication resources may refer to a combination of radio frequency spectrum resources, time resources, and spatial resources (e.g., spatial layers or beams), and the use of multiple spatial layers may further improve the data rate or data integrity of communications with UE 115.

[0141] One or more parameter designs for a carrier may be supported, where the parameter designs may include a subcarrier spacing (Δf) and a cyclic prefix. A carrier may be divided into one or more BWPs with the same or different parameter designs. In some examples, a UE 115 may be configured with multiple BWPs. In some examples, a single BWP for a carrier may be active at a given time, and communications for a UE 115 may be limited to the one or more active BWPs. A time interval for a base station 105 or a UE 115 may be expressed in multiples of a base time unit, which may be, for example, a sampling period T s =1 / (Δf max ·N f ) seconds, where Δf max It can represent the maximum supported subcarrier spacing, and N f The maximum supported discrete Fourier transform (DFT) size may be represented. Time intervals of communication resources may be organized according to radio frames, each having a specific 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).

[0142] Each frame may include a plurality of consecutively numbered subframes or time slots, and each subframe or time 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 time slots. Alternatively, each frame may include a variable number of time slots, and the number of time slots may depend on the subcarrier spacing. Each time slot may include a number of code element periods (e.g., depending on the length of the cyclic prefix added before each code element period). In some wireless communication systems 100, a time slot may be further divided into a plurality of mini-time slots containing one or more code elements. Excluding the cyclic prefix, each code element period may contain one or more (e.g., N fThe duration of a symbol period may depend on the subcarrier spacing or the operating band.

[0143] A subframe, slot, mini-slot, or symbol may be the smallest scheduling unit (e.g., in the time domain) of the wireless communication 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 communication system 100 may be dynamically selected (e.g., in bursts of shortened TTIs (sTTIs)).

[0144] Physical channels may be multiplexed on a carrier according to various techniques. Physical control channels and physical data channels may be multiplexed on a downlink carrier, for example, using one or more of time division multiplexing (TDM), frequency division multiplexing (FDM), or hybrid TDM-FDM techniques. A control region (e.g., a control resource set (CORESET)) for physical control channels may be defined by a number of symbol periods and may extend across the system bandwidth or a subset of the system bandwidth of a carrier. One or more control regions (e.g., CORESETs) may be configured for a set of UEs 115. For example, one or more of UEs 115 may monitor or search the control region for control information according to one or more search space sets, and each search space set may include one or more 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 the 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. The search space sets may include a common search space set configured for transmitting control information to multiple UEs 115 and a UE-specific search space set for transmitting control information to a specific UE 115 .

[0145] Each base station 105 may provide communication coverage via one or more cells (e.g., macro cells, small cells, hotspots, or other types of cells, or any combination thereof). The term "cell" may refer to a logical communication entity used to communicate with a base station 105 (e.g., on a carrier) and may be associated with an identifier (e.g., a physical cell identifier (PCID), a virtual cell identifier (VCID), or other) used to distinguish between adjacent cells. In some examples, a cell may also refer to a geographic coverage area 110 or a portion of a geographic coverage area 110 (e.g., a sector) on which the logical communication entity operates. The scope of such a cell may range from a smaller area (e.g., a structure, a subset of structures) to a larger area depending on various factors (such as the capabilities of the base station 105). For example, a cell may be or include a building, a subset of buildings, or an external space between or overlapping geographic coverage areas 110, among other examples.

[0146] A macro cell covers a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access to UEs 115 that have service subscriptions with a network provider that supports the macro cell. A small cell may be associated with a lower-power base station 105 (compared to a macro cell) and may operate in the same or different frequency bands (e.g., licensed or unlicensed) as the macro cell. A small cell may provide unrestricted access to UEs 115 that have service subscriptions with the network provider, or may provide restricted access to UEs 115 associated with the small cell (e.g., UEs 115 in a closed subscriber group (CSG) or UEs 115 associated with users in a home or office). A base station 105 may support one or more cells and may also support communication over one or more cells using one or more component carriers. In some examples, a carrier may support multiple cells, and different cells may be configured according to different protocol types (e.g., MTC, narrowband IoT (NB-IoT), enhanced mobile broadband (eMBB)) that may provide access to different types of devices.

[0147] In some examples, base stations 105 can be mobile and, therefore, provide communication coverage for mobile geographic coverage areas 110. In some examples, different geographic coverage areas 110 associated with different technologies can overlap, but the different geographic coverage areas 110 can be supported by the same base station 105. In other examples, overlapping geographic coverage areas 110 associated with different technologies can be supported by different base stations 105. The wireless communication system 100 can include, for example, a heterogeneous network in which different types of base stations 105 provide coverage for various geographic coverage areas 110 using the same or different radio access technologies.

[0148] The wireless communication system 100 may support synchronous or asynchronous operation. For synchronous operation, the base stations 105 may have similar frame timing, and transmissions from different base stations 105 may be approximately aligned in time. For asynchronous operation, the base stations 105 may have different frame timing, and transmissions from different base stations 105 may not be aligned in time in some examples. The techniques described herein may be used for either synchronous or asynchronous operation.

[0149] Some UEs 115, such as MTC or IoT devices, may be low-cost or low-complexity devices and may provide automated communication between machines (e.g., via machine-to-machine (M2M) communication). M2M communication or MTC may refer to data communication technology that allows devices to communicate with each other or with a base station 105 without human intervention. In some examples, M2M communication or MTC may include communications from devices that incorporate sensors or meters to measure or capture information and relay such information to a central server or application that utilizes the information or presents it to a person interacting with the application. Some UEs 115 may be designed to collect information or implement 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, wilderness survival monitoring, weather and geographic event monitoring, queue management and tracking, remote security sensing, physical access control, and transaction-based commercial charging.

[0150] Some UEs 115 may be configured to employ a reduced power consumption mode of operation, such as half-duplex communication (e.g., a mode that supports unidirectional communication via transmission or reception but not simultaneous transmission and reception). In some examples, half-duplex communication may be performed at a reduced peak rate. Other power saving techniques for UEs 115 include entering a power-saving deep sleep mode when not engaged in active communication, operating over a limited bandwidth (e.g., according to narrowband communication), or a combination of these techniques. For example, some UEs 115 may be configured to operate using a narrowband protocol type that is associated with a defined portion or range (e.g., a set of subcarriers or resource blocks (RBs)) within a carrier, within a guard band of a carrier, or outside a carrier.

[0151] The wireless communication system 100 can be configured to support ultra-reliable communication or low-latency communication or various combinations thereof. For example, the wireless communication system 100 can be configured to support ultra-reliable low-latency communication (URLLC) or mission-critical communication. The UE 115 can be designed to support ultra-reliable, low-latency or critical functions (e.g., mission-critical functions). Ultra-reliable communication can include private communication or group communication and can be supported by one or more mission-critical services such as mission-critical push-to-talk (MCPTT), mission-critical video (MCVideo), or mission-critical data (MCData). Support for mission-critical functions can include prioritization of services, and mission-critical services can be used for public safety or commercial applications. The terms ultra-reliable, low-latency, mission-critical, and ultra-reliable low-latency can be used interchangeably herein.

[0152] In some examples, 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 communication may be within the geographic coverage area 110 of base station 105. Other UEs 115 in such a group may be outside the geographic coverage area 110 of base station 105 or otherwise unable to receive transmissions from base station 105. In some examples, a group of UEs 115 communicating via D2D communication 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, base station 105 facilitates the scheduling of resources for D2D communication. In other cases, D2D communication is performed between UEs 115 without involving base station 105.

[0153] In some systems, the D2D communication link 135 can be an example of a communication channel (such as a sidelink communication channel) between vehicles (e.g., UE 115). In some examples, the vehicles can communicate using vehicle-to-everything (V2X) communication, vehicle-to-vehicle (V2V) communication, or some combination of these communications. The vehicles can signal information related to traffic conditions, signal scheduling, weather, safety, emergency situations, or any other information related to the V2X system. In some examples, the vehicles in the V2X system can use vehicle-to-network (V2N) communication to communicate with roadside infrastructure (such as roadside units), with the network, or with both via one or more network nodes (e.g., base station 105).

[0154] 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 a 5G core (5GC), and the EPC or 5GC may include at least one control plane entity (e.g., a mobility management entity (MME), an access and mobility management function (AMF)) that manages access and mobility, and at least one user plane entity (e.g., a serving gateway (S-GW), a packet data network (PDN) gateway (P-GW), or a user plane function (UPF)) that routes packets or interconnects to external networks. The control plane entity may manage non-access stratum (NAS) functions such as mobility, authentication, and bearer management for UEs 115 served by base stations 105 associated with the core network 130. User IP packets may be delivered through the user plane entity, which may provide IP address allocation and other functions. The user plane entity may be connected to the network operator IP service 150. Operator IP services 150 may include access to the Internet, an intranet, an IP Multimedia Subsystem (IMS), or packet-switched streaming services.

[0155] Some network devices (such as base stations 105) may include subcomponents, such as access network entities 140, which may be examples of access node controllers (ANCs). Each access network entity 140 may communicate with each UE 115 through one or more other access network transport entities 145, which may be referred to as radio heads, smart radio heads, or transmit / receive points (TRPs). Each access network transport entity 145 may include one or more antenna panels. In some configurations, the 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., base station 105).

[0156] The wireless communication system 100 may operate using one or more frequency bands in the range of 300 megahertz (MHz) to 300 gigahertz (GHz). The 300 MHz to 3 GHz region is referred to as the ultra-high frequency (UHF) region or decimeter band because the wavelengths range from approximately 1 decimeter to 1 meter long. UHF waves can be blocked or redirected by buildings and environmental features, but these waves can penetrate various structures sufficiently for macrocells to provide service to UEs 115 located indoors. Transmissions using UHF waves may be associated with smaller antennas and a shorter range (e.g., less than 100 kilometers) than transmissions using the lower frequencies and longer wavelengths in the high frequency (HF) or very high frequency (VHF) portions of the spectrum below 300 MHz.

[0157] The wireless communication system 100 may also operate in the super high frequency (SHF) region of the frequency band from 3 GHz to 30 GHz (also known as the centimeter band) or in the 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 communication system 100 may support millimeter wave (mmW) communications between the UE 115 and the base station 105, and the EHF antennas of the corresponding devices may be smaller and more closely spaced than the UHF antennas. In some examples, this may facilitate the use of antenna arrays within the device. However, the propagation of EHF transmissions may be subject to even greater atmospheric attenuation and a shorter range than SHF or UHF transmissions. The techniques disclosed herein may be employed across transmissions using one or more different frequency regions, and the use of frequency bands specified across these frequency regions may vary by country or regulatory agency.

[0158] The electromagnetic spectrum is typically subdivided into various classes, bands, channels, etc. based on frequency / wavelength. In 5G NR, two initial operating bands have been identified as frequency range designations FR1 (410 MHz–7.125 GHz) and FR2 (24.25 GHz–52.6 GHz). It should be understood that although a portion of FR1 is greater than 6 GHz, FR1 is often (interchangeably) referred to as the "sub-6 GHz band" in various documents and articles. A similar naming issue sometimes arises with respect to FR2, which is often (interchangeably) referred to as the "millimeter wave" band in various documents and articles, although it is different from the EHF band (30 GHz–300 GHz) identified as the "millimeter wave" band by the International Telecommunication Union (ITU).

[0159] Frequencies between FR1 and FR2 are generally referred to as mid-band frequencies. Recent 5G NR research has identified the operating bands for these mid-band frequencies as frequency range designation FR3 (7.125 GHz–24.25 GHz). Frequency bands falling within FR3 can inherit FR1 characteristics and / or FR2 characteristics, and thus can effectively extend the features of FR1 and / or FR2 to mid-band frequencies. In addition, higher frequency bands are currently being explored to extend 5G NR operation to above 52.6 GHz. For example, three higher operating bands have been identified as frequency range designations FR4a or FR4-1 (52.6 GHz–71 GHz), FR4 (52.6 GHz–114.25 GHz), and FR5 (114.25 GHz–300 GHz). Each of these higher frequency bands falls within the EHF band.

[0160] In view of the above aspects, unless otherwise specified, it should be understood that the terms "sub-6 GHz" and the like, if used herein, can broadly refer to frequencies that may be less than 6 GHz, may be within FR1, or may include mid-band frequencies. Furthermore, unless otherwise specified, it should be understood that the terms "millimeter wave" and the like, if used herein, can broadly refer to frequencies that may include mid-band frequencies, may be within FR2, FR4, FR4-a or FR4-1 and / or FR5, or may be within the EHF band.

[0161] The wireless communication system 100 may utilize both licensed and unlicensed radio frequency spectrum bands. For example, the wireless communication system 100 may employ licensed 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 an unlicensed radio frequency spectrum band, devices (such as base stations 105 and UEs 115) may employ carrier sensing for collision detection and avoidance. In some examples, operations in the unlicensed band may be based on a carrier aggregation configuration (e.g., LAA) in conjunction with component carriers operating in the licensed band. Operations in the unlicensed spectrum may include downlink transmissions, uplink transmissions, P2P transmissions, or D2D transmissions, among others.

[0162] The base station 105 or UE 115 may be equipped with multiple antennas that can be used to employ techniques such as transmit diversity, receive diversity, multiple-input multiple-output (MIMO) communications, or beamforming. The antennas of the base station 105 or UE 115 may be located within one or more antenna arrays or antenna panels that can 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, the antennas or antenna arrays associated with the base station 105 may be located at different geographical locations. The base station 105 may have an antenna array having several rows and columns of antenna ports that the base station 105 can use to support beamforming for communications with the UE 115. Similarly, the UE 115 may have one or more antenna arrays that can support various MIMO or beamforming operations. Additionally or alternatively, the antenna panel may support radio frequency beamforming for signals transmitted via the antenna ports.

[0163] The base station 105 or the UE 115 can use MIMO communication to exploit multipath signal propagation and improve spectral efficiency by transmitting or receiving multiple signals via different spatial layers. Such a technique may be referred to as spatial multiplexing. For example, a transmitting device may transmit multiple signals via different antennas or different antenna combinations. Similarly, a receiving device may receive multiple signals via different antennas or different antenna combinations. 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 for channel measurement and reporting. MIMO techniques include single-user MIMO (SU-MIMO), in which multiple spatial layers are transmitted to the same receiving device, and multi-user MIMO (MU-MIMO), in which multiple spatial layers are transmitted to multiple devices.

[0164] Beamforming (which may also be referred to as spatial filtering, directional transmission, or directional reception) is a signal processing technique that can be used at a transmitting device or a receiving device (e.g., base station 105, 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 can be achieved by combining signals communicated via antenna elements of an antenna array so that some signals propagating at a particular orientation relative to the antenna array experience constructive interference, while other signals experience destructive interference. Adjustments to signals communicated via antenna elements can include the transmitting device or the receiving device applying an amplitude offset, a phase offset, or both to the signals carried via the antenna elements associated with that device. The adjustments associated with each antenna element can be defined by a set of beamforming weights associated with a particular orientation (e.g., relative to the antenna array of the transmitting device or the receiving device, or relative to some other orientation).

[0165] The base station 105 or the UE 115 may use beam sweeping techniques as part of a beamforming operation. For example, the base station 105 may use multiple antennas or antenna arrays (e.g., antenna panels) to perform beamforming operations for directional communication with the UE 115. Some signals (e.g., synchronization signals, reference signals, beam selection signals, or other control signals) may be transmitted multiple times by the base station 105 in different directions. For example, the base station 105 may transmit signals according to different sets of beamforming weights associated with different transmission directions. The transmissions in different beam directions may be used (e.g., by a transmitting device (such as the base station 105) or a receiving device (such as the UE 115)) to identify a beam direction for later transmission or reception by the base station 105.

[0166] Some signals, such as data signals associated with a particular recipient device, may be transmitted by base station 105 in a single beam direction, e.g., a direction associated with a recipient device, such as UE 115. In some examples, a beam direction associated with transmissions along a single beam direction may be determined based on signals transmitted in one or more beam directions. For example, UE 115 may receive one or more signals transmitted by base station 105 in different directions and may report to base station 105 an indication of the signal received by UE 115 with the highest signal quality or other acceptable signal quality.

[0167] In some examples, transmission by a device (e.g., by a base station 105 or a UE 115) may be performed using multiple beam directions, and the device may use a combination of digital precoding or radio frequency beamforming to generate a combined beam for transmission (e.g., from the base station 105 to the UE 115). The UE 115 may report feedback indicating precoding weights for one or more beam directions, and the feedback may correspond to a configured number of beams across the system bandwidth or one or more subbands. The base station 105 may transmit reference signals (e.g., cell-specific reference signals (CRS), channel state information reference signals (CSI-RS)) that may be precoded or uncoded. The UE 115 may provide feedback for beam selection, which may be a precoding matrix indicator (PMI) or codebook-based feedback (e.g., a multi-panel type codebook, a linear combination type codebook, a port selection type codebook). Although these techniques are described with reference to signals transmitted by base station 105 in one or more directions, UE 115 may use similar techniques to transmit signals multiple times in different directions (e.g., to identify a beam direction for subsequent transmission or reception by UE 115) or to transmit signals in a single direction (e.g., to transmit data to a receiving device).

[0168] A receiving device (e.g., UE 115) may attempt multiple receive configurations (e.g., directional listening) when receiving various signals (such as synchronization signals, reference signals, beam selection signals, or other control signals) from base station 105. For example, the receiving device may attempt multiple receive directions by receiving via different antenna subarrays, processing received signals according to different antenna subarrays, receiving according to different receive beamforming weight sets applied to signals received at multiple antenna elements of an antenna array (e.g., different directional listening weight sets), or processing received signals according to different receive beamforming weight sets applied to signals received at multiple antenna elements of an antenna array, any of which may be referred to as "listening according to different receive configurations" or "listening according to different receive configurations" or "listening according to receive directions." In some examples, the receiving device may use a single receive configuration to receive along a single beam direction (e.g., when receiving data signals). The single receive configuration may be aligned on a beam direction determined based on listening according to different receive configuration directions (e.g., a beam direction determined to have the highest signal strength, highest signal-to-noise ratio (SNR), or other acceptable signal quality based on listening according to multiple beam directions).

[0169] The wireless communication system 100 can be a packet-based network that operates according to a layered protocol stack. In the user plane, the communication of the bearer or packet data convergence protocol (PDCP) layer can be IP-based. The radio link control (RLC) layer can perform packet segmentation and reassembly to communicate on the logical channel. The media access control (MAC) layer can perform priority handling and multiplex the logical channel into the transport channel. The MAC layer can also use error detection technology, error correction technology, or both to support retransmission of the MAC layer to improve link efficiency. In the control plane, the RRC protocol layer can provide the establishment, configuration and maintenance of the RRC connection of the radio bearer that supports user plane data between the UE 115 and the base station 105 or the core network 130. In the physical layer, the transport channel can be mapped to the physical channel.

[0170] UE 115 and base station 105 may support retransmission of data to increase the likelihood that the data is successfully received. HARQ feedback is a technique for increasing the likelihood that data is correctly received on 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 MAC layer throughput in poor radio conditions (e.g., low signal-to-noise ratio conditions). In some examples, a device may support simultaneous slot HARQ feedback, wherein the device may provide HARQ feedback in a particular time slot for data received in a previous symbol in that time slot. In other cases, the device may provide HARQ feedback in a subsequent time slot or based on some other time interval.

[0171] The wireless communication system 100 may support various random access procedures (such as two-step or four-step random access procedures). These random access procedures may also be contention-based or contention-free. As the demand for communication efficiency increases, the wireless communication system 100 may support efficient contention resolution operations for contention-based random access procedures by reducing latency associated with contention resolution operations, etc. For example, the wireless communication system 100 may be a non-terrestrial communication system (e.g., a LEO communication system, a GEO communication system) and may experience improvements to random access procedures by supporting early contention resolution operations, as described herein.

[0172] The UE 115 may include a UE communication manager 101 that may support efficient contention resolution operations for contention-based random access procedures. The UE communication manager 101 may be such as Figures 5 to 8 Similarly, the base station 105 may include a base station communication manager 102 that may support efficient contention resolution operations for contention-based random access procedures. The base station communication manager 102 may be such as Figures 9 to 12 Examples of aspects of a base station communications manager are described in .

[0173] As an example, as part of a four-step random access procedure, the base station 105 and the UE 115 may exchange one or more random access messages (e.g., handshake messages), such as msg1, msg2, msg3, and msg4. In this example, the random access procedure may be contention-based. To reduce latency associated with the contention-based portion of the random access procedure, the base station 105 may perform early contention resolution operations. The base station 105 may perform early contention resolution operations with the UE after receiving msg3 during the random access procedure. In some examples, the contention resolution operations may correspond to a contention resolution window, which may be associated with a contention resolution timer.

[0174] The base station 105 may perform an early contention resolution operation (i.e., attempt to resolve contention) while suspending the transmission of msg4 to the UE 115. As part of the early contention resolution operation, the base station 105 may transmit a contention resolution MAC-CE without transmitting msg4. The contention resolution MAC-CE may include a contention resolution identifier that the UE may use to declare the success or failure of the random access procedure. For example, the UE 115 may receive the contention resolution identifier and compare it with an identifier specific to the UE 115 (e.g., C-RNTI). When the identifiers match, the UE 115 may declare the random access procedure successful. Otherwise, if there is no match between the identifiers, the UE 115 may determine that the random access procedure has failed and may repeat the random access procedure with the base station 105.

[0175] In some examples, the UE 115 may be configured to disable HARQ feedback for the random access procedure. As a result, the base station 105 may not know whether the UE 115 has received a contention resolution MAC-CE (including a contention resolution identifier) and whether the UE has determined whether the random access procedure is successful or failed. Various aspects of the described technology relate to configuring the base station 105 and the UE 115 to support flexible HARQ feedback to provide efficient contention resolution operation for contention-based random access procedures. For example, the base station 105 and the UE 115 may be configured to support reduced latency associated with contention resolution operation when HARQ feedback is disabled or enabled based in part on a trigger (e.g., an indication, a configuration).

[0176] Figure 2 An example of a wireless communication system 200 according to one or more aspects of the present disclosure is illustrated. In some examples, the wireless communication system 200 may implement aspects of the wireless communication system 100. For example, the wireless communication system 200 may include a UE 115-a and a base station 105-a within a geographic coverage area 110-a. The base station 105-a and the UE 115-a may be referenced to Figure 1 Examples of corresponding devices described. For example, base station 105-a can be a terrestrial base station or a non-terrestrial base station or a combination thereof (e.g., gNB-CU plus gNB-DU). In some examples, wireless communication system 200 can support multiple radio access technologies, including 4G systems (such as LTE systems, LTE-A systems, or LTE-A Pro systems), 5G systems (which can be referred to as NR systems), and non-terrestrial systems (e.g., LEO systems, GEO systems). The wireless communication system 200 can also support improvements in power consumption and, in some examples, can provide benefits such as enhanced efficiency for high reliability and low latency random access operations.

[0177] The base station 105-a and the UE 115-a may be configured with multiple antennas, which may be used to employ techniques such as transmit diversity, receive diversity, multiple-input multiple-output communications, or beamforming, or any combination thereof. The antennas of the base station 105-a and the UE 115-a may be located within one or more antenna arrays or antenna panels that may support multiple-input multiple-output operations or transmit or receive beamforming. For example, the base station 105-a antennas or antenna arrays may be co-located at an antenna assembly (such as an antenna tower). In some examples, the antennas or antenna arrays associated with the base station 105-a may be located at different geographical locations. The base station 105-a may have an antenna array having several rows and columns of antenna ports that the base station 105-a may use to support beamforming for communications with the UE 115-a. Similarly, the UE 115-a may have one or more antenna arrays that may support various multiple-input multiple-output or beamforming operations. Additionally or alternatively, the antenna panel may support radio frequency beamforming for signals transmitted via one or more antenna ports. The base station 105 - a and the UE 115 - a may thus be configured to support directional communication via the communication link 205 using multiple antennas.

[0178] A UE 115-a in the wireless communication system 200 may support operations for preserving resources (e.g., time and frequency resources of the wireless communication system 200), battery life of the UE 115-a, and the like. In some examples, the UE 115-a may be configured to support operations for managing or improving the communication link 205 between the base station 105-a and the UE 115-a. For example, the base station 105-a may configure the UE 115-a to support a connection procedure (e.g., a random access procedure) with the UE 115-a. The base station 105-a and the UE 115-a may perform a random access procedure to establish a connection (e.g., a communication link 205). In other examples, the base station 105-a and the UE 115-a may perform a random access procedure to reestablish a connection (e.g., a communication link 205) after a connection failure (e.g., a radio link failure) with the base station 105-a, or to establish a connection for handover to another base station, and the like.

[0179] The random access procedure may be a two-step or four-step random access procedure. These random access procedures may also be contention-based or contention-free. As part of the four-step random access procedure, the base station 105-a and the UE 115-a may exchange one or more random access messages 210 (e.g., handshake messages), such as msg1, msg2, msg3, and msg4. Figure 2In an example, a base station 105-a may transmit multiple downlink data channel transmissions 215 on a communication link 205, and a UE 115-a may receive multiple downlink data channel transmissions 215 on the communication link 205. The downlink data channel transmissions 215 may be associated with a random access procedure. For example, the base station 105-a may transmit the downlink data channel transmissions 215 during a contention resolution window associated with the random access procedure, and the UE 115-a may receive the downlink data channel transmissions 215 during the contention resolution window, as described herein. In some examples, one or more of the downlink data channel transmissions may carry one or more of the random access messages 210. The random access procedure may be contention-based. msg1 may include a random access preamble or a sequence that may carry information (such as a UE identifier). The purpose of the preamble may be to provide an indication to the base station 105-a of the presence of a random access attempt and to allow the base station 105-a to determine a delay (e.g., a timing delay) between the base station 105-a and the UE 115-a. UE 115 - a may transmit msg1 to base station 105 - a , for example, on a physical random access channel (PRACH).

[0180] In some examples, the preamble of msg 1 may be defined by a preamble sequence and a cyclic prefix. The preamble sequence may be defined in part based on a Zadoff-Chu sequence. UE 115-a may additionally or alternatively use a protection period to handle the timing uncertainty of msg 1. For example, before starting the random access procedure, UE 115-a may obtain downlink synchronization with base station 105-a based in part on a cell search procedure. However, because UE 115-a has not yet obtained uplink synchronization with base station 105-a, there may be uncertainty in the uplink timing due to not knowing the location of UE 115-a in the cell (e.g., the geographic coverage area of base station 105-a). In some examples, the uncertainty in the uplink timing may be based in part on the size (e.g., size, area) of the cell (e.g., the geographic coverage area 110-a). Therefore, in some examples, including a cyclic prefix to msg 1 may be beneficial for handling uncertainty in uplink timing.

[0181] There may be a number of preamble sequences per cell (e.g., 64 preamble sequences). UE 115-a may select a preamble sequence from a set of sequences in a cell (e.g., the geographic coverage area of base station 105-a) based in part on random selection. In some examples, UE 115-a may select a preamble sequence based in part on the amount of traffic UE 115-a has for transmission on an uplink shared channel (UL-SCH). Based on the preamble sequence selected by UE 115-a, base station 105-a may determine an amount of uplink resources to grant to UE 115-a.

[0182] As described herein, some examples of random access procedures may be contention-based or contention-free. When performing a contention-based random access procedure, the UE 115-a may select a preamble sequence from a set of sequences. That is, as long as other UEs (not shown) are not performing a random access attempt using the same sequence at the same time instance, no collision will occur and the random access attempt may be detected by the base station 105-a. If the UE 115-a is performing a contention-free random access attempt (e.g., to switch to a new cell), the preamble sequence to be used may be explicitly signaled by the base station 105-a (e.g., in control information). To avoid collisions or interference, the base station 105-a may select a contention-free preamble sequence from a sequence that is not associated with a contention-based random access attempt.

[0183] Upon receiving msg1, the base station 105-a may appropriately respond with msg2. For example, the base station 105-a may transmit msg2 to the UE 115-a on a downlink shared channel (DL-SCH) or a physical downlink control channel (PDCCH). In some examples, msg 2 may have the same or a different configuration (format) as msg 1. msg 2 may carry information for the UE 115-a, where the information is determined by the base station 105-a based in part on the information carried in msg1. For example, the information in msg2 may include an index of a detected preamble sequence for which a response is valid, a timing advance determined in part based on the detected preamble sequence, a scheduling grant indicating time and frequency resources for the UE 115-a to use for transmitting the next random access message transmission by the UE 115-a, or a network identifier (e.g., RNTI) for further communication with the UE 115-a, and the like.

[0184] In some examples, upon receiving the timing advance in msg2, UE 115-a may activate an uplink alignment timer (e.g., timeAlignmentTimer). UE 115-a may extend the value of the uplink alignment timer to account for the propagation delay period between base station 105-a and UE 115-a. Contention resolution may be considered successful for the system information request after receiving the contention resolution identifier MAC-CE. If configured, UE 115-a may deactivate the uplink alignment timer without waiting to transmit HARQ feedback.

[0185] Once UE 115-a successfully receives msg2, UE 115-a can obtain uplink synchronization with base station 105-a. In some examples, before data transmission from UE 115-a, a unique identifier within the cellular cell (e.g., C-RNTI) can be assigned to UE 115-a. In some examples, depending on the RRC state of UE 115-a (e.g., RRC connected state, RRC ideal state), additional messages (e.g., connection request messages) may need to be exchanged to establish a connection between base station 105-a and UE 115-a. UE 115-a can use the UL-SCH resources (or physical uplink shared channel (PUSCH) resources) assigned in msg2 to transmit any necessary messages (e.g., msg3) to base station 105-a. msg2 may include a UE identifier for contention resolution. For example, if UE 115-a is in an RRC connected state, the UE identifier may be a C-RNTI. Otherwise, the UE identifier may be specific to UE 115-a.

[0186] Base station 105-a may receive msg 3 and may respond correctly, for example, by transmitting msg 4 (which may be a contention resolution message). When multiple UEs (including UE 115-a) are performing random access attempts simultaneously using the same preamble sequence, these UEs may cause the same response message (e.g., msg 4) to be listened to. Each UE (including UE 115-a) may receive msg 4 and compare the identifier (e.g., network identifier) in msg 4 with the identifier specified in msg 3. When the identifiers match, the corresponding UE (e.g., UE 115-a) may declare the random access procedure successful. A UE that does not identify a match between the identifiers is deemed to have failed the random access procedure and may repeat the random access procedure with base station 105-a. As a result of the connection procedure, base station 105-a and UE 115-a may establish a connection (e.g., communication link 205).

[0187] In some examples, the base station 105-a and the UE 115-a can be configured to support early contention resolution for the random access procedure to reduce the latency associated with the contention-based portion of the random access procedure. For example, the base station 105-a can perform early contention resolution operations after receiving msg3 from the UE 115-a during the random access procedure. Figure 3 An example of a transmission timeline is described in more detail.

[0188] Figure 3 An example of a transmission timeline 300 according to one or more aspects of the present disclosure is illustrated. The transmission timeline 300 may be implemented with reference to Figure 1 and 2 Aspects of the described wireless communication systems 100 and 200. For example, the transmission timeline 300 may be based on configuration performed by the base station 105-a and configuration implemented by the UE 115-b, which may be referenced. Figure 1 and 2 Examples of corresponding devices are described. Transmission timeline 300 may illustrate a portion of a random access procedure. For example, transmission timeline 300 may be applicable to an implementation or instance in which base station 105-b and UE 115-b are performing early contention resolution for a random access procedure (e.g., a four-step random access procedure) that may be contention-based.

[0189] As part of a random access procedure, UE 115-b may transmit msg1 345 to base station 105-b. msg1 345 may include a random access preamble or a sequence that may carry information, such as a UE identifier for UE 115-b. In response to msg1 345, base station 105-b may transmit msg2 350 to base station 105-b. msg2 350 may carry information about UE 115-b, where the information is determined by base station 105-b based in part on the information carried in msg1 345. For example, the information in msg2 350 may include an index of a detected preamble sequence for which a response is valid, a timing advance determined based in part on the detected preamble sequence, a scheduling grant (e.g., msg3) indicating time and frequency resources for UE 115-b to use for transmitting the next random access message transmission by UE 115-b, or a network identifier (e.g., RNTI) for further communication with UE 115-b, and the like.

[0190] In the example of a four-step random access procedure, UE 115-b may transmit msg3 305 to base station 105-b. Figure 3In an example, base station 105-b and UE 115-b may support early contention resolution for a random access procedure. For example, base station 105-a may perform early contention resolution operations after receiving msg3 305 from UE 115-b during a random access procedure. In other words, base station 105-b may perform early contention resolution operations (i.e., attempt to resolve contention) while suspending transmission of msg4 325 to UE 115-b. As part of the early contention resolution operations, base station 105-b may transmit a contention resolution identifier 310 in a contention resolution MAC-CE during a contention resolution window 315 without transmitting msg4 325. The contention resolution window 315 may correspond to a system bandwidth, which may be associated with time resources (e.g., symbols, mini-slots, slots, subframes, frames, etc.) and frequency resources (e.g., subcarriers, carriers, etc.).

[0191] UE 115-b may use the contention resolution identifier 310 in the contention resolution MAC-CE to declare that the random access procedure was successful or unsuccessful. For example, UE 115-b may receive the contention resolution identifier and compare it with an identifier specific to UE 115-b (e.g., a cell-specific radio network temporary identifier (C-RNTI)). When the identifiers match, UE 115-b may declare that the random access procedure was successful. Otherwise, if there is no match between the identifiers, UE 115-b may determine that contention resolution has failed and may repeat the random access procedure with base station 105-b. In some examples, UE 115-b may transmit a feedback message 320 (e.g., a HARQ message) to base station 105-b indicating whether contention resolution was successful (e.g., via an acknowledgment) or failed (e.g., via a negative acknowledgment). In some examples, if contention resolution is successful, base station 105-b may transmit an RRC configuration in msg4 325 on PDSCH.

[0192] In some examples, the UE 115-b may monitor the contention resolution window 315 according to one or more DRX cycles for the contention resolution identifier 310. For example, the contention resolution window 315 may correspond to the DRX cycle 335, and the UE 115-b may monitor the contention resolution window 315 during one or more active durations 340 of the DRX cycle 335 for a contention resolution MAC-CE carrying the contention resolution identifier 310. In some examples, the UE 115-b may reduce power consumption (e.g., operate in a partial low power state) by refraining from monitoring the contention resolution window 315 during the inactive durations of the DRX cycle 335. In some examples, the one or more active durations 340 may be continuous or non-continuous. Similarly, the one or more inactive durations of the DRX cycle 335 may be continuous or non-continuous.

[0193] In some examples, the contention resolution window 315 may be associated with a contention resolution timer, and the UE 115-b may activate or deactivate the contention resolution timer based in part on the propagation delay period 330. In an example of non-terrestrial communication, such as when the base station 105-b is a satellite or a high-altitude platform station, the UE 115-b may be configured with a contention resolution timer value to cover the propagation delay period 330 between the base station 105-b and the UE 115-b. The propagation delay period 330 may be attributable to the propagation distance from the base station 105-b (e.g., a satellite) to the UE 115-b on the ground, or vice versa. As such, the UE 115-b may activate or deactivate the contention resolution timer based in part on the propagation delay period 330, and perform contention resolution operations according to the activation or deactivation of the contention resolution timer. In some examples, UE 115-b may activate a contention resolution timer based in part on transmitting msg3 305 and deactivate the contention resolution timer after a time has elapsed (e.g., the value expires).

[0194] The base station 105-b may transmit and the UE 115-b may receive a configuration regarding a contention resolution timer and set a value for the contention resolution timer based on the configuration. The value of the contention resolution timer may be based on one or more of: a maximum propagation delay between the UE 115-b and the base station 105-b, a duration of a transmission time interval (TTI) associated with the transmission of a contention resolution identifier, or a gap between a downlink data channel (e.g., PDSCH) reception and an uplink control channel (e.g., PUCCH) transmission, or a combination thereof. In some examples, the value of the contention resolution timer may be a factor of one or more of the above. That is, the value of the contention resolution timer may be the maximum propagation delay between the UE 115-b and the base station 105-b plus the duration of the TTI associated with the transmission of the contention resolution identifier plus 2 times the gap between a downlink data channel (e.g., PDSCH) reception and an uplink control channel (e.g., PUCCH) transmission.

[0195] By supporting an adaptive contention resolution timer, the base station 105-b and the UE 115-b may provide greater reliability to random access procedures (e.g., mitigating or reducing random access message losses due to high propagation delays, etc.). Additionally, by supporting an adaptive contention resolution timer, the base station 105-b and the UE 115-b may experience improvements in power consumption and, in some examples, may promote enhanced efficiency for high reliability and low latency operation in 5G systems, among other benefits.

[0196] return Figure 2In some examples, the temporary C-RNTI and the C-RNTI may be the same, and more than one UE 115 may receive the same PDSCH. The RRC message (e.g., an RRC setup message) may be extended to include a contention resolution identifier. To reduce overhead, the base station 105-a and the UE 115-a may be configured to support a reduced contention resolution identifier in the RRC message. Alternatively, the contention resolution identifier may be a default contention resolution identifier. In some examples, if the UE 115-a receives an RRC configuration in msg4 without contention resolution, the UE 115-a may provide an indication that the contention has not been resolved in a random access message 5 (msg5) (e.g., an RRC setup complete message). The base station 105-a may confirm or verify the RRC reconfiguration for the UE 115-a in a subsequent contention resolution operation (e.g., a subsequent random access procedure attempt). In some other examples, the UE 115-a may ignore msg5 because the contention resolution identifier has not been received. In some examples, UE 115-a may be configured to disable HARQ feedback for the random access procedure. Figure 4 An example of a transmission timeline associated with disabled HARQ feedback is described in more detail.

[0197] Figure 4 An example of a transmission timeline 400 according to one or more aspects of the present disclosure is illustrated. The transmission timeline 400 may be implemented with reference to Figure 1 and 2 Aspects of the described wireless communication systems 100 and 200. For example, the transmission timeline 400 may be based on configurations performed by the base station 105-c and configurations implemented by the UE 115-c, which may be referenced. Figure 1 and 2 Examples of corresponding devices described. Transmission timeline 400 may illustrate a portion of a random access procedure. For example, transmission timeline 400 may be applicable to implementations or instances when base station 105-c and UE 115-c are configured to support early contention resolution for a random access procedure (which may be contention-based).

[0198] As part of a random access procedure, UE 115-c may transmit msg1 425 to base station 105-c. msg1 425 may include a random access preamble or a sequence that may carry information, such as a UE identifier for UE 115-c. In response to msg1 425, base station 105-c may transmit msg2 430 to base station 105-c. msg2 430 may carry information for UE 115-c, where the information is determined by base station 105-c based in part on the information carried in msg1 425. For example, the information in msg2 430 may include an index of a detected preamble sequence for which a response is valid, a timing advance determined based in part on the detected preamble sequence, a scheduling grant (e.g., msg3) indicating time and frequency resources for UE 115-c to use for transmitting the next random access message transmission by UE 115-c, or a network identifier (e.g., RNTI) for further communication with UE 115-c, and the like.

[0199] In the example of a four-step random access procedure, UE 115-c may transmit msg3 405 to base station 105-c. Figure 4 In an example of a system 105-c, a base station 105-c and a UE 115-c may support early contention resolution for a random access procedure. For example, the base station 105-c may perform early contention resolution operations after receiving msg3 405 from the UE 115-c during the random access procedure. In other words, the base station 105-c may perform early contention resolution operations (i.e., attempt to resolve contention) while suspending transmission of msg4 420 to the UE 115-c. As part of the early contention resolution operations, the base station 105-c may transmit a contention resolution identifier 410 in a contention resolution MAC-CE during a contention resolution window 415 without transmitting msg4 420. The contention resolution window 415 may correspond to a system bandwidth, which may be associated with time resources (e.g., symbols, mini-slots, slots, subframes, frames, etc.) and frequency resources (e.g., subcarriers, carriers, etc.).

[0200] The UE 115-c may use the contention resolution identifier 410 in the contention resolution MAC-CE to declare the random access procedure successful or unsuccessful. For example, the UE 115-c may receive the contention resolution identifier and compare it with an identifier specific to the UE 115-c (e.g., a cell-specific radio network temporary identifier (C-RNTI)). When the identifiers match, the UE 115-c may declare the random access procedure successful. Otherwise, if there is no match between the identifiers, the UE 115-c may consider the contention resolution to have failed and may repeat the random access procedure with the base station 105-c.

[0201] However, in Figure 4 In the example of FIG4 , UE 115-c may not transmit any feedback message (e.g., HARQ message) to base station 105-c to indicate whether contention resolution is successful (e.g., via an acknowledgment) or failed (e.g., via a negative acknowledgment). In some cases, if base station 105-c mistakenly assumes that UE 115-c received contention resolution identifier 410, when UE 115-c did not actually receive contention resolution identifier 410, base station 105-c may transmit the RRC configuration in msg4 420 on PDSCH after contention resolution window 415 expires. Therefore, base station 105-c may not know whether UE 115-c has received contention resolution MAC-CE (including contention resolution identifier 410) and whether UE 115-c has determined whether the random access procedure is successful or failed.

[0202] return Figure 2 , in order to alleviate Figure 4 To address the issues described in

[0015] , base station 105-a and UE 115-a may be configured to support flexible HARQ feedback to provide efficient contention resolution operations for contention-based random access procedures. For example, base station 105-a and UE 115-a may be configured to support reduced latency associated with contention resolution operations when HARQ feedback is disabled or enabled. UE 115-a may transmit msg3 associated with the random access procedure to base station 105-a. In this example, HARQ feedback is disabled for the random access procedure.

[0203] UE 115-a may monitor a contention resolution window associated with a random access procedure for a first downlink data channel transmission (e.g., a PDSCH transmission) associated with msg4. The first downlink data channel transmission (e.g., a PDSCH transmission) may carry a contention resolution MAC-CE. UE 115-a may transmit acknowledgment information (e.g., HARQ feedback) regarding the first downlink data channel transmission (e.g., a PDSCH transmission) carrying the contention resolution MAC-CE based on an indication (e.g., an acknowledgment or a negative acknowledgment) that HARQ feedback is to be enabled. Thus, UE 115-a may be configured to exclusively provide HARQ feedback for the first PDSCH received for msg4 (i.e., the PDSCH carrying the contention resolution MAC-CE) even when HARQ feedback is initially disabled.

[0204] In some examples, UE 115-a may identify an indication in UE context information that HARQ feedback is to be enabled. In some other examples, an indication indicating whether HARQ feedback is to be provided may be indicated in msg3 (e.g., in a downlink RRC message). In some examples, UE 115-a may identify a default configuration to enable HARQ feedback. In other examples, the indication may be configured or broadcast by base station 105-a. Additionally or alternatively, the indication may be provided in a downlink communication carrying a contention resolution MAC-CE. For example, UE 115-a may receive an indication in a contention resolution MAC-CE. The indication may be a single bit or a multi-bit indication, which may be one or more reserved bits in a MAC-CE field of the contention resolution MAC-CE. In some examples, UE 115-a may receive a DCI message that schedules a first downlink data channel transmission (e.g., a first PDSCH transmission) carrying a contention resolution MAC-CE. The DCI message may include an indication that HARQ feedback is to be enabled. In other words, the DCI scheduling the PDSCH carrying the contention resolution MAC-CE may indicate whether HARQ feedback for the random access procedure is to be enabled.

[0205] UE 115-a may receive a resource allocation associated with one or more uplink control channel resources from base station 105-a to transmit HARQ feedback. In some examples, UE 115-a may determine resources (e.g., uplink control channel resources) associated with an uplink control channel (e.g., PUCCH) based on an indication in a contention resolution MAC-CE. The indication may be a logical channel identifier. The resources may also be adjacent to the end resources of the contention resolution window. That is, the resources for HARQ feedback may be preconfigured at the end of the contention resolution window. The resources may include time resources (e.g., symbols, mini-slots, slots, subframes, frames, etc.).

[0206] In some other examples, UE 115-a may receive a DCI message that schedules resources associated with an uplink control channel. That is, the PUCCH acknowledgment resources may be provided by the DCI message. In this manner, UE 115-a may determine the scheduled resources based on one or more resource indices in the DCI message. The one or more resource indices may correspond to the scheduled resources. In other words, multiple predefined PUCCH acknowledgment resources may be defined, and the index indicating the PUCCH acknowledgment resource to be used may be indicated by the DCI message.

[0207] In some examples, UE 115-a may determine that reception of a first downlink data channel transmission (e.g., a first PDSCH) carrying a contention resolution MAC-CE has failed. In this case, UE 115-a may transmit a negative acknowledgment to base station 105-a. For example, UE 115-a may have received the PDCCH (PDSCH and feedback scheduling), but failed to receive the PDSCH carrying the MAC-CE, thereby triggering the negative acknowledgment. In some examples, UE 115-a may transmit a negative acknowledgment after the contention resolution timer expires. For example, if UE 115-a receives nothing in the contention resolution window, UE 115-a may transmit a negative acknowledgment before declaring the random access procedure failed. In some examples, UE 115-a may wait for the contention resolution timer to expire (e.g., 2 times the propagation delay time for receiving any PDCCH after sending the negative acknowledgment). If nothing is received, UE 115-a may retry transmitting msg1 at the next opportunity (eg, a subsequent contention resolution window), skipping any backoff.

[0208] In some examples, HARQ feedback may be disabled and UE 115-a may not support flexible HARQ feedback (e.g., acknowledgment, negative acknowledgment). For example, UE 115-a may monitor a contention resolution window associated with a random access procedure for a downlink data channel transmission (e.g., a PDSCH transmission) carrying a contention resolution MAC-CE and, based on the disabled HARQ feedback, refrain from transmitting acknowledgment information (e.g., HARQ feedback) about a downlink data channel transmission carrying a random access response message including a contention resolution MAC-CE. In some other examples, base station 105-a and UE 115-a may be configured not to support early contention resolution (i.e., msg4 includes a contention resolution MAC-CE plus a downlink common control channel (CCCH) and a dedicated control channel (DCCH) SDU).

[0209] To mitigate the issues described herein, the base station 105-a and the UE 115-a may be configured to support a number of repetitions associated with a downlink data channel transmission (e.g., a PDSCH) carrying a contention resolution MAC-CE. For example, the UE 115-a may be configured to monitor the contention resolution window for a number of repetitions associated with the downlink data channel transmission carrying the contention resolution MAC-CE. In some examples, the UE 115-a may receive a configuration that includes an indication of a number of repetitions associated with the downlink data channel transmission carrying the contention resolution MAC-CE. In some examples, a single PDCCH may schedule multiple transport blocks including a contention resolution MAC-CE repeated in msg4.

[0210] Figure 5 A block diagram 500 of a device 505 is shown according to one or more aspects of the present disclosure. The device 505 may be an example of aspects of the UE 115 as described herein. The device 505 may include a receiver 510, a UE communication manager 515, and a transmitter 520. The device 505 may also include a processor. Each of these components may be in communication with each other (e.g., via one or more buses).

[0211] The receiver 510 may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to contention resolution in new radio non-terrestrial networks, etc.). The information may be passed to other components of the device 505. The receiver 510 may be a reference Figure 8 Examples of aspects of the described transceiver 820. The receiver 510 may utilize a single antenna or a collection of antennas.

[0212] The UE communication manager 515 may determine that HARQ feedback is disabled; transmit a random access message associated with a random access procedure to a base station based on determining that the HARQ feedback is disabled; initiate a contention resolution window associated with the random access procedure for a downlink data channel transmission associated with the random access procedure in a downlink data channel transmission set; and receive the downlink data channel transmission during the contention resolution window, the downlink data channel transmission carrying a contention resolution MAC-CE.

[0213] The UE communication manager 515 may also determine that HARQ feedback is disabled for the random access procedure; transmit a random access message associated with the random access procedure to the base station based on determining that HARQ feedback is disabled for the random access procedure; and suppress transmitting acknowledgment information about a downlink data channel transmission carrying a random access response message including a contention resolution MAC-CE based on the disabled HARQ feedback.

[0214] The UE communication manager 515 may also transmit a random access message associated with a random access procedure to the base station, wherein HARQ feedback is disabled for the random access procedure; monitor the contention resolution window associated with the random access procedure to find the first downlink data channel transmission associated with the random access procedure in the downlink data channel transmission set, the first downlink data channel transmission carrying a contention resolution MAC-CE; and transmit acknowledgment information about the first downlink data channel transmission carrying the contention resolution MAC-CE based on an indication that HARQ feedback is to be enabled.

[0215] The UE communication manager 515 may also transmit a random access message associated with a random access procedure to the base station, wherein HARQ feedback is disabled for the random access procedure; monitor the contention resolution window associated with the random access procedure to find a downlink data channel transmission carrying a contention resolution MAC-CE; and suppress the transmission of acknowledgment information about a downlink data channel transmission carrying a random access response message including the contention resolution MAC-CE based on the disabled HARQ feedback.

[0216] The UE communication manager 515 may also transmit a random access message associated with a random access procedure to the base station; determine that HARQ feedback is disabled for the random access procedure; and suppress transmission of acknowledgment information regarding a downlink data channel transmission carrying a random access response message including a contention resolution MAC-CE or an SDU associated with a downlink shared control channel, or one or more of the two based on the disabled HARQ feedback.

[0217] The UE communication manager 515 may also transmit a random access message associated with a random access procedure to a base station; receive a random access response message associated with the random access procedure, the random access response message including a timing advance; determine that HARQ feedback is disabled for the random access procedure; and control an uplink alignment timer based on the timing advance or the disabled HARQ feedback, or both.

[0218] The UE communication manager 515 may also transmit a random access message associated with a random access procedure to the base station; receive a configuration regarding a contention resolution timer; set a value of the contention resolution timer based on the configuration; monitor a contention resolution window associated with the random access procedure based on the value of the contention resolution timer to find a first downlink data channel transmission associated with the random access procedure in a downlink data channel transmission set, the first downlink data channel transmission carrying a contention resolution MAC-CE; and transmit confirmation information regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0219] The UE communication manager 515 may also transmit a random access message associated with a random access procedure to a base station; monitor a contention resolution window associated with the random access procedure to find a first downlink data channel transmission associated with the random access procedure in a downlink data channel transmission set, the first downlink data channel transmission carrying a contention resolution MAC-CE; and transmit an acknowledgment regarding the first downlink data channel transmission carrying the contention resolution MAC-CE. The UE communication manager 515 may be an example of aspects of the UE communication manager 810 described herein.

[0220] The UE communication manager 515 may be an example of a means for performing various aspects of managing contention resolution as described herein. The UE communication manager 515 or its subcomponents may be implemented in hardware (e.g., in UE communication management circuitry). The circuitry may include a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described in this disclosure.

[0221] In another implementation, the UE communication manager 515 or its subcomponents may be implemented in code executed by a processor (e.g., as communication management software or firmware), or any combination thereof. If implemented in code executed by a processor, the functions of the UE communication manager 515 or its subcomponents may be performed by a general-purpose processor, DSP, ASIC, FPGA, or other programmable logic device.

[0222] In some examples, UE communications manager 515 may be configured to perform various operations (e.g., receive, determine, monitor, initiate, transmit) using or otherwise coordinating with receiver 510, transmitter 520, or both.

[0223] The UE communications manager 515 or its subcomponents may be physically located in a variety of locations, including being distributed such that portions of functionality are implemented by one or more physical components at different physical locations. In some examples, according to various aspects of the present disclosure, the UE communications manager 515 or its subcomponents may be separate and distinct components. In some examples, according to various aspects of the present disclosure, the UE communications manager 515 or its subcomponents may be combined with one or more other hardware components (including, but not limited to, input / output (I / O) components, a transceiver, a network server, another computing device, one or more other components described in the present disclosure, or a combination thereof).

[0224] The transmitter 520 may transmit signals generated by other components of the device 505. In some examples, the transmitter 520 may be co-located with the receiver 510 in a transceiver module. For example, the transmitter 520 may be a reference Figure 8 Examples of aspects of the described transceiver 820. The transmitter 520 may utilize a single antenna or a collection of antennas.

[0225] By including or configuring the UE communication manager 515 according to the examples described herein, the device 510 (e.g., a processor controlling or otherwise coupled to the receiver 515, the UE communication manager 515, the transmitter 520, or a combination thereof) can reduce processing resources and power consumption associated with random access procedures. For example, by supporting early contention resolution operations, the device 505 can provide enhanced efficiency for high reliability and low latency random access operations, among other benefits.

[0226] Figure 6 A block diagram 600 of a device 605 is shown according to one or more aspects of the present disclosure. The device 605 may be an example of aspects of the device 505 or UE 115 as described herein. The device 605 may include a receiver 610, a UE communication manager 615, and a transmitter 640. The device 605 may also include a processor. Each of these components may be in communication with each other (e.g., via one or more buses).

[0227] The receiver 610 may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to contention resolution in new radio non-terrestrial networks, etc.). The information may be passed to other components of the device 605. The receiver 610 may be a reference Figure 8 Examples of aspects of the described transceiver 820. The receiver 610 may utilize a single antenna or a collection of antennas.

[0228] UE communication manager 615 may be an example of aspects of UE communication manager 515 as described herein. UE communication manager 615 may include message component 620, window component 625, feedback component 630, and timer component 635. UE communication manager 615 may be an example of aspects of UE communication manager 810 as described herein.

[0229] The message component 620 may determine that HARQ feedback is disabled and may transmit a random access message associated with the random access procedure to the base station based on the determination that HARQ feedback is disabled. The window component 625 may initiate a contention resolution window associated with the random access procedure for downlink data channel transmissions associated with the random access procedure in a downlink data channel transmission set; and may receive the downlink data channel transmission during the contention resolution window, the downlink data channel transmission carrying a contention resolution MAC-CE.

[0230] The message component 620 may determine that HARQ feedback is disabled for the random access procedure and may transmit a random access message associated with the random access procedure to the base station based on the determination that HARQ feedback is disabled for the random access procedure. The feedback component 630 may refrain from transmitting acknowledgment information regarding a downlink data channel transmission carrying a random access response message including a contention resolution MAC-CE based on the disabled HARQ feedback.

[0231] The message component 620 can transmit a random access message associated with a random access procedure to a base station. The timer component 635 can receive a configuration regarding a contention resolution timer and can set a value for the contention resolution timer based on the configuration. The window component 625 can monitor a contention resolution window associated with the random access procedure based on the value set for the contention resolution timer to find the first downlink data channel transmission associated with the random access procedure in a downlink data channel transmission set, the first downlink data channel transmission carrying a contention resolution MAC-CE. The feedback component 630 can transmit acknowledgment information regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0232] The message component 620 can transmit a random access message associated with a random access procedure to a base station, wherein HARQ feedback is disabled for the random access procedure. The window component 625 can monitor the contention resolution window associated with the random access procedure to find the first downlink data channel transmission associated with the random access procedure in the downlink data channel transmission set, the first downlink data channel transmission carrying a contention resolution MAC-CE. The feedback component 630 can transmit an acknowledgment regarding the first downlink data channel transmission carrying the contention resolution MAC-CE based on the indication that HARQ feedback is to be enabled.

[0233] The message component 620 can transmit a random access message associated with a random access procedure to a base station, wherein HARQ feedback is disabled for the random access procedure. The window component 625 can monitor the contention resolution window associated with the random access procedure for downlink data channel transmissions carrying a contention resolution MAC-CE. The feedback component 630 can refrain from transmitting acknowledgment information regarding downlink data channel transmissions carrying random access response messages including a contention resolution MAC-CE based on the disabled HARQ feedback.

[0234] The message component 620 can transmit a random access message associated with a random access procedure to a base station. The window component 625 can determine that HARQ feedback is disabled for the random access procedure. The feedback component 630 can refrain from transmitting acknowledgment information regarding a downlink data channel transmission carrying a random access response message including one or more of a contention resolution MAC-CE or an SDU associated with a downlink shared control channel, or both, based on the disabled HARQ feedback.

[0235] The message component 620 can transmit a random access message associated with a random access procedure to a base station and receive a random access response message associated with the random access procedure, the random access response message including a timing advance. The feedback component 630 can determine that HARQ feedback is disabled for the random access procedure. The timer component 635 can control an uplink alignment timer based on the timing advance, the disabled HARQ feedback, or both.

[0236] The message component 620 can transmit a random access message associated with a random access procedure to a base station. The window component 625 can monitor a contention resolution window associated with the random access procedure to find a first downlink data channel transmission associated with the random access procedure in a downlink data channel transmission set, the first downlink data channel transmission carrying a contention resolution MAC-CE. The feedback component 630 can transmit acknowledgment information exclusively (e.g., only) for the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0237] The transmitter 640 may transmit signals generated by other components of the device 605. In some examples, the transmitter 640 may be co-located with the receiver 610 in a transceiver module. For example, the transmitter 640 may be a reference Figure 8 Examples of aspects of the described transceiver 820. The transmitter 640 may utilize a single antenna or a collection of antennas.

[0238] Figure 7 A block diagram 700 of a UE communication manager 705 is shown in accordance with one or more aspects of the present disclosure. The UE communication manager 705 may be an example of aspects of the UE communication manager 515, the UE communication manager 615, or the UE communication manager 810 described herein. The UE communication manager 705 may include a messaging component 710, a window component 715, a feedback component 720, a resource component 725, a configuration component 730, and a timer component 735. Each of these modules may communicate with each other directly or indirectly (e.g., via one or more buses).

[0239] The message component 710 may determine that HARQ feedback is disabled and may transmit a random access message associated with a random access procedure to a base station based on the determination that HARQ feedback is disabled. The window component 715 may initiate a contention resolution window associated with the random access procedure for downlink data channel transmissions associated with the random access procedure in a downlink data channel transmission set; and may receive the downlink data channel transmission during the contention resolution window, the downlink data channel transmission carrying a contention resolution MAC-CE.

[0240] The message component 710 may determine that HARQ feedback is disabled for the random access procedure and may transmit a random access message associated with the random access procedure to the base station based on the determination that HARQ feedback is disabled for the random access procedure. The feedback component 720 may refrain from transmitting acknowledgment information regarding a downlink data channel transmission carrying a random access response message including a contention resolution MAC-CE based on the disabled HARQ feedback.

[0241] The message component 710 can transmit a random access message associated with a random access procedure to a base station. The timer component 735 can receive a configuration regarding a contention resolution timer and can set a value for the contention resolution timer based on the configuration. The window component 715 can monitor a contention resolution window associated with the random access procedure based on the value set for the contention resolution timer to find the first downlink data channel transmission associated with the random access procedure in a downlink data channel transmission set, the first downlink data channel transmission carrying a contention resolution MAC-CE. The feedback component 720 can transmit an acknowledgment regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0242] The message component 710 may transmit a random access message associated with a random access procedure to a base station, wherein HARQ feedback is disabled for the random access procedure. In some examples, the message component 710 may transmit a random access message associated with a random access procedure to a base station, wherein HARQ feedback is disabled for the random access procedure. In some examples, the message component 710 may transmit a random access message associated with a random access procedure to a base station. In some examples, the message component 710 may transmit a random access message associated with a random access procedure to a base station.

[0243] In some examples, the message component 710 can receive a random access response message associated with the random access procedure, the random access response message including a timing advance. In some examples, the message component 710 can transmit a random access message associated with the random access procedure to the base station. In some examples, the message component 710 can transmit in the random access message a request to enable HARQ feedback for the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0244] In some examples, message component 710 may receive a DCI message scheduling a first downlink data channel transmission carrying a contention resolution MAC-CE, wherein the DCI message includes an indication that HARQ feedback is to be enabled. In some examples, message component 710 may transmit an RRC message indicating a failure of contention resolution associated with the random access procedure. In some examples, message component 710 may receive a downlink control channel carrying a DCI message scheduling one or more transport blocks associated with a number of repetitions of a downlink data channel transmission associated with the contention resolution MAC-CE. In some cases, the random access message includes msg3. In some cases, the base station is a non-terrestrial base station, such as a satellite or a high-altitude platform station in a non-terrestrial network. In some cases, the contention resolution MAC-CE includes a contention resolution identifier. In some cases, the length of the contention resolution identifier in the contention resolution MAC-CE is less than or equal to a default length of a default contention resolution identifier.

[0245] The window component 715 can monitor a contention resolution window associated with the random access procedure for a first downlink data channel transmission in a set of downlink data channel transmissions associated with the random access procedure, the first downlink data channel transmission carrying a contention resolution MAC-CE. In some examples, the window component 715 can monitor a contention resolution window associated with the random access procedure for a downlink data channel transmission carrying a contention resolution MAC-CE. In some examples, the window component 715 can determine that HARQ feedback is disabled for the random access procedure.

[0246] In some examples, the window component 715 may monitor a contention resolution window associated with the random access procedure for a first downlink data channel transmission associated with the random access procedure in a set of downlink data channel transmissions, the first downlink data channel transmission carrying a contention resolution MAC-CE. In some examples, the window component 715 may monitor the contention resolution window during one or more active durations associated with the one or more DRX cycles. In some examples, the window component 715 may monitor the contention resolution window for a number of repetitions associated with the downlink data channel transmission carrying the contention resolution MAC-CE. In some examples, the window component 715 may monitor the contention resolution window associated with the random access procedure for a downlink data channel transmission carrying a random access response message including one or more of a contention resolution MAC-CE or an SDU associated with a downlink shared control channel, or both.

[0247] In some examples, the window component 715 can monitor the contention resolution window during one or more active durations associated with the one or more DRX cycles. In some examples, the window component 715 can monitor the contention resolution window during one or more active durations associated with the one or more DRX cycles. In some cases, the contention resolution window includes one or more DRX cycles.

[0248] The feedback component 720 may, based on the indication that HARQ feedback is to be enabled, transmit acknowledgment information exclusively (e.g., only) for the first downlink data channel transmission carrying the contention resolution MAC-CE. In some examples, the feedback component 720 may, based on the disabled HARQ feedback, refrain from transmitting acknowledgment information for a downlink data channel transmission carrying a random access response message including the contention resolution MAC-CE. In some examples, the feedback component 720 may, based on the disabled HARQ feedback, refrain from transmitting acknowledgment information for a downlink data channel transmission carrying a random access response message including one or more of the contention resolution MAC-CE or an SDU associated with a downlink shared control channel, or both. In some examples, the feedback component 720 may determine that HARQ feedback is disabled for the random access procedure. In some examples, the feedback component 720 may transmit acknowledgment information for the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0249] In some examples, feedback component 720 may identify an indication to enable HARQ feedback based on UE context information, a network configuration for enabling HARQ feedback, a default configuration for enabling HARQ feedback, or a combination thereof. In some examples, feedback component 720 may enable HARQ feedback based on the indication. In some examples, feedback component 720 may receive an indication in a contention resolution MAC-CE. In some examples, feedback component 720 may enable HARQ feedback based on the indication in the contention resolution MAC-CE.

[0250] In some examples, feedback component 720 may determine that reception of a first downlink data channel transmission carrying a contention resolution MAC-CE failed, wherein HARQ feedback is enabled for the random access procedure and the acknowledgment information includes a negative acknowledgment. In some examples, feedback component 720 may transmit the acknowledgment information based on the elapsed contention resolution window, wherein HARQ feedback is enabled for the random access procedure and the acknowledgment information includes a negative acknowledgment. In some examples, feedback component 720 may determine to transmit acknowledgment information regarding the first downlink data channel transmission carrying the contention resolution MAC-CE, wherein transmitting the acknowledgment information regarding the first downlink data channel transmission carrying the contention resolution MAC-CE is based on the determination. In some examples, feedback component 720 may transmit the acknowledgment information based on the elapsed contention resolution window, the acknowledgment information including a negative acknowledgment. In some cases, the indication includes a bit indication. In some cases, the bit indication includes a reserved bit in a MAC subheader of the contention resolution MAC-CE. In some cases, the acknowledgment information includes a positive acknowledgment or a negative acknowledgment.

[0251] The timer component 735 may control the uplink alignment timer based on the timing advance or the disabled HARQ feedback, or both. In some examples, the timer component 735 may set the uplink alignment timer based on a configuration. In some examples, the timer component 735 may activate the uplink alignment timer based on receiving a random access response message including a timing advance. In some examples, the timer component 735 may deactivate the uplink alignment timer based on receiving a contention resolution MAC-CE and before transmitting an acknowledgment of a downlink data channel transmission carrying the contention resolution MAC-CE, or both. In some cases, the value of the uplink alignment timer is based on one or more of the following: a maximum propagation delay between the UE and the base station, a duration of a transmission time interval, or a gap between a downlink data channel reception and an uplink control channel transmission, or a combination thereof.

[0252] The resource component 725 may determine the scheduled resources based on one or more resource indices in the DCI message, the one or more resource indices corresponding to the scheduled resources. In some cases, the resource component 725 may determine the resources associated with the uplink control channel based on a second indication in the contention resolution MAC-CE, wherein transmitting the acknowledgment information includes transmitting the acknowledgment information on the uplink control channel using the determined resources. In some cases, the second indication includes a new MAC-CE providing uplink control channel resources. In some cases, the logical channel identifier of the MAC-CE is the same as or different from that of the contention resolution MAC-CE. In some cases, the resources are adjacent to the end of the contention resolution window. In some cases, a DCI message is received that schedules resources associated with the uplink control channel, wherein transmitting the acknowledgment information includes transmitting the acknowledgment information on the uplink control channel using the scheduled resources.

[0253] Configuration component 730 may receive a configuration regarding a resource resolution timer. In some examples, configuration component 730 may set a value for the contention resolution timer based on the configuration. In some examples, configuration component 730 may receive a configuration including an indication of a number of repetitions associated with a downlink data channel transmission carrying a contention resolution MAC-CE. In some examples, configuration component 730 may receive a configuration regarding a resource resolution timer. In some examples, configuration component 730 may set a value for the contention resolution timer based on the configuration. In some examples, configuration component 730 may start a contention resolution timer associated with a contention resolution window, wherein monitoring the contention resolution window is based on the contention resolution timer. In some examples, configuration component 730 may monitor the contention resolution window during one or more active durations associated with the one or more DRX cycles. In some examples, configuration component 730 may receive a configuration regarding a resource resolution timer.

[0254] In some examples, configuration component 730 can set a value for a contention resolution timer based on the configuration. In some examples, configuration component 730 can start a contention resolution timer associated with a contention resolution window, wherein monitoring the contention resolution window is based on the contention resolution timer. In some examples, configuration component 730 can receive a configuration regarding a resource resolution timer. In some examples, configuration component 730 can set a value for a contention resolution timer based on the configuration.

[0255] In some cases, the value of the contention resolution timer is based on one or more of the following: a maximum propagation delay between the UE and the base station, a duration of a transmission time interval associated with the transmission of a contention resolution identifier, or a gap between downlink data channel reception and uplink control channel transmission, or a combination thereof. In some cases, the value of the contention resolution timer is based on one or more of the following: a maximum propagation delay between the UE and the base station, a duration of a transmission time interval associated with the transmission of a contention resolution identifier, or a gap between downlink data channel reception and uplink control channel transmission, or a combination thereof. In some cases, the contention resolution window includes one or more DRX cycles. In some cases, the value of the contention resolution timer is based on one or more of the following: a maximum propagation delay between the UE and the base station, a duration of a transmission time interval associated with the transmission of a contention resolution identifier, or a gap between downlink data channel reception and uplink control channel transmission, or a combination thereof.

[0256] Figure 8 A diagram of a system 800 including a device 805 according to one or more aspects of the present disclosure is shown. The device 805 may be an example of, or include a component of, a device 505, a device 605, or a UE 115 as described herein. The device 805 may include components for two-way voice and data communications, including components for transmitting and receiving communications, including a UE communications manager 810, an I / O controller 815, a transceiver 820, an antenna 825, a memory 830, and a processor 840. These components may be in electronic communication via one or more buses (e.g., a bus 845).

[0257] The UE communication manager 810 may determine that HARQ feedback is disabled; transmit a random access message associated with a random access procedure to a base station based on determining that the HARQ feedback is disabled; initiate a contention resolution window associated with the random access procedure for a downlink data channel transmission associated with the random access procedure in a downlink data channel transmission set; and receive the downlink data channel transmission during the contention resolution window, the downlink data channel transmission carrying a contention resolution MAC-CE.

[0258] The UE communication manager 810 may also determine that HARQ feedback is disabled for the random access procedure; transmit a random access message associated with the random access procedure to the base station based on determining that HARQ feedback is disabled for the random access procedure; and suppress transmitting acknowledgment information about a downlink data channel transmission carrying a random access response message including a contention resolution MAC-CE based on the disabled HARQ feedback.

[0259] The UE communication manager 810 may also transmit a random access message associated with a random access procedure to a base station; receive a configuration regarding a contention resolution timer; set a value of a contention resolution timer based on the configuration; monitor a contention resolution window associated with the random access procedure based on the value of the contention resolution timer to search for a first downlink data channel transmission associated with the random access procedure in a downlink data channel transmission set, the first downlink data channel transmission carrying a contention resolution MAC-CE; and transmit confirmation information regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0260] The UE communication manager 810 may also transmit a random access message associated with a random access procedure to a base station, wherein HARQ feedback is disabled for the random access procedure; monitor a contention resolution window associated with the random access procedure to find a first downlink data channel transmission associated with the random access procedure in a downlink data channel transmission set, the first downlink data channel transmission carrying a contention resolution MAC-CE; and transmit acknowledgment information about the first downlink data channel transmission carrying the contention resolution MAC-CE based on an indication that HARQ feedback is to be enabled.

[0261] The UE communication manager 810 may also transmit a random access message associated with a random access procedure to a base station, wherein HARQ feedback is disabled for the random access procedure; monitor a contention resolution window associated with the random access procedure to find a downlink data channel transmission carrying a contention resolution MAC-CE; and suppress transmission of acknowledgment information regarding a downlink data channel transmission carrying a random access response message including the contention resolution MAC-CE based on the disabled HARQ feedback.

[0262] The UE communication manager 810 may also transmit a random access message associated with a random access procedure to a base station; determine that HARQ feedback is disabled for the random access procedure; and suppress transmission of acknowledgment information regarding a downlink data channel transmission carrying a random access response message including a contention resolution MAC-CE or an SDU associated with a downlink shared control channel, or one or more of the two based on the disabled HARQ feedback.

[0263] The UE communication manager 810 may also transmit a random access message associated with a random access procedure to a base station; receive a random access response message associated with the random access procedure, the random access response message including a timing advance; determine that HARQ feedback is disabled for the random access procedure; and control an uplink alignment timer based on the timing advance or the disabled HARQ feedback, or both.

[0264] The UE communication manager 810 may also transmit a random access message associated with a random access procedure to a base station; monitor a contention resolution window associated with the random access procedure to find a first downlink data channel transmission associated with the random access procedure in a downlink data channel transmission set, the first downlink data channel transmission carrying a contention resolution MAC-CE; and transmit acknowledgment information about the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0265] By including or configuring the UE communication manager 810 according to the examples described herein, the device 805 can provide improvements to the random access procedure. For example, by supporting early contention resolution operations, the device 805 can promote improvements in efficiency and resource usage of the random access procedure, and in some examples can promote spectrum efficiency, reduced latency, reduced power consumption, improved coordination between the UE and the core network, and increased battery life, among other benefits.

[0266] I / O controller 815 can manage input and output signals for device 805. I / O controller 815 can also manage peripheral devices that are not integrated into device 805. In some cases, I / O controller 815 can represent a physical connection or port to an external peripheral device. In some cases, I / O controller 815 can utilize an operating system, such as or another known operating system. In other cases, I / O controller 815 may represent or interact with a modem, keyboard, mouse, touch screen, or similar device. In some cases, I / O controller 815 may be implemented as part of a processor. In some cases, a user may interact with device 805 via I / O controller 815 or via hardware components controlled by I / O controller 815.

[0267] The transceiver 820 can communicate bidirectionally via one or more antennas, wired or wireless links, as described above. For example, the transceiver 820 can represent a wireless transceiver and can communicate bidirectionally with another wireless transceiver. The transceiver 820 can also include a modem to modulate packets and provide the modulated packets to the antenna for transmission, and to demodulate packets received from the antenna. In some cases, the device 805 can include a single antenna 825. However, in some cases, the device 805 can have more than one antenna 825, which can be capable of concurrently transmitting or receiving multiple wireless transmissions.

[0268] The memory 830 may include random access memory (RAM) and read-only memory (ROM). The memory 830 may store computer-readable, computer-executable code 835 including instructions that, when executed, cause the processor to perform the various functions described herein. In some cases, the memory 830 may include, among other things, a BIOS that may control basic hardware or software operations, such as interaction with peripheral components or devices.

[0269] The code 835 may include instructions for implementing various aspects of the present disclosure, including instructions for supporting wireless communications. The code 835 may be stored in a non-transitory computer-readable medium, such as system memory or other types of memory. In some cases, the code 835 may not be directly executed by the processor 840, but may cause a computer (e.g., when compiled and executed) to perform the functions described herein.

[0270] The processor 840 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, discrete gate or transistor logic components, discrete hardware components, or any combination thereof). In some cases, the processor 840 may be configured to operate a memory array using a memory controller. In other cases, the memory controller may be integrated into the processor 840. The processor 840 may be configured to execute computer-readable instructions stored in a memory (e.g., memory 830) to cause the device 805 to perform various functions (e.g., functions or tasks supporting contention resolution in a new radio non-terrestrial network).

[0271] Figure 9 A block diagram 900 of a device 905 is shown in accordance with one or more aspects of the present disclosure. The device 905 may be an example of aspects of a base station 105 as described herein. The device 905 may include a receiver 910, a base station communication manager 915, and a transmitter 920. The device 905 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

[0272] The receiver 910 may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to contention resolution in new radio non-terrestrial networks, etc.). The information may be passed to other components of the device 905. The receiver 910 may be a reference Figure 12 Examples of aspects of the described transceiver 1220. The receiver 910 may utilize a single antenna or a collection of antennas.

[0273] The base station communication manager 915 may receive a random access message associated with a random access procedure from the UE, wherein HARQ feedback is disabled for the random access procedure, and wherein a contention resolution window is associated with the random access procedure for downlink data channel transmissions associated with the random access procedure in a downlink data channel transmission set; and transmit the downlink data channel transmission during the contention resolution window, the downlink data channel transmission carrying a contention resolution MAC-CE.

[0274] The base station communication manager 915 can receive a random access message associated with a random access procedure from the UE; transmit a configuration about a contention resolution timer; transmit a first downlink data channel transmission associated with the random access procedure in a downlink data channel transmission set during a contention resolution window associated with the random access procedure based on the configuration about the contention resolution timer; the first downlink data channel transmission carries a contention resolution MAC-CE; and receive confirmation information about the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0275] The base station communication manager 915 may also receive a random access message associated with a random access procedure from the UE, wherein HARQ feedback is disabled for the random access procedure; determine a contention resolution window associated with the random access procedure for a first downlink data channel transmission associated with the random access procedure in a downlink data channel transmission set, the first downlink data channel transmission carrying a contention resolution MAC-CE; and receive acknowledgment information about the first downlink data channel transmission carrying the contention resolution MAC-CE based on transmitting an indication to the UE to enable HARQ feedback.

[0276] The base station communication manager 915 may also receive a random access message associated with a random access procedure from the UE, wherein HARQ feedback is disabled for the random access procedure; determine a contention resolution window associated with the random access procedure for downlink data channel transmissions carrying a contention resolution MAC-CE; and refrain from receiving acknowledgment information regarding downlink data channel transmissions carrying a random access response message including the contention resolution MAC-CE based on the disabled HARQ feedback. The base station communication manager 915 may be an example of various aspects of the base station communication manager 1210 described herein.

[0277] By including or configuring the base station communication manager 915 according to the examples described herein, the device 905 (e.g., a processor controlling or otherwise coupled to the receiver 910, the base station communication manager 915, the transmitter 920, or a combination thereof) can reduce processing resources and power consumption associated with random access procedures. For example, by supporting early contention resolution operations, the device 905 can promote enhanced efficiency for high reliability and low latency random access operations, among other benefits.

[0278] The base station communication manager 915 may be an example of a means for performing various aspects of managing contention resolution as described herein. The base station communication manager 915 or its subcomponents may be implemented in hardware (e.g., in base station communication management circuitry). The circuitry may include a general purpose processor, a DSP, an ASIC, an FPGA, or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described in this disclosure.

[0279] In another implementation, the base station communication manager 915 or its subcomponents can be implemented in code executed by a processor (e.g., as communication management software or firmware), or any combination thereof. If implemented in code executed by a processor, the functionality of the base station communication manager 915 or its subcomponents can be performed by a general-purpose processor, a DSP, an ASIC, an FPGA, or other programmable logic device. In some examples, the base station communication manager 915 can be configured to use or otherwise cooperate with the receiver 910, the transmitter 920, or both to perform various operations (e.g., receive, determine, suppress, transmit).

[0280] The base station communications manager 915 or its subcomponents may be physically located at various locations, including being distributed such that portions of functionality are implemented by one or more physical components at different physical locations. In some examples, according to various aspects of the present disclosure, the base station communications manager 915 or its subcomponents may be separate and distinct components. In some examples, according to various aspects of the present disclosure, the base station communications manager 915 or its subcomponents may be combined with one or more other hardware components (including, but not limited to, I / O components, a transceiver, a network server, another computing device, one or more other components described in the present disclosure, or a combination thereof).

[0281] The transmitter 920 may transmit signals generated by other components of the device 905. In some examples, the transmitter 920 may be co-located with the receiver 910 in a transceiver module. For example, the transmitter 920 may be a reference Figure 12 Examples of aspects of the described transceiver 1220. The transmitter 920 may utilize a single antenna or a collection of antennas.

[0282] Figure 10 Block diagram 1000 of a device 1005 according to one or more aspects of the present disclosure is shown. Device 1005 may be an example of aspects of device 905 or base station 105 as described herein. Device 1005 may include a receiver 1010, a base station communication manager 1015, and a transmitter 1035. Device 1005 may also include a processor. Each of these components may be in communication with each other (e.g., via one or more buses).

[0283] The receiver 1010 may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to contention resolution in new radio non-terrestrial networks, etc.). The information may be passed to other components of the device 1005. The receiver 1010 may be a reference Figure 12 Examples of aspects of the described transceiver 1220. The receiver 1010 may utilize a single antenna or a collection of antennas.

[0284] Base station communications manager 1015 can be an example of aspects of base station communications manager 915 as described herein. Base station communications manager 1015 can include a message component 1020, a window component 1025, and a feedback component 1030. Base station communications manager 1015 can be an example of aspects of base station communications manager 1210 as described herein.

[0285] The message component 1020 can receive, from the UE, a random access message associated with a random access procedure, wherein HARQ feedback is disabled for the random access procedure, and wherein a contention resolution window is associated with the random access procedure for downlink data channel transmissions associated with the random access procedure in a downlink data channel transmission set. The window component 1025 can transmit the downlink data channel transmission during the contention resolution window, the downlink data channel transmission carrying a contention resolution MAC-CE.

[0286] The message component 1020 may receive a random access message associated with a random access procedure from a UE and may transmit a configuration regarding a contention resolution timer. The window component 1025 may transmit, based on the configuration regarding the contention resolution timer, a first downlink data channel transmission associated with the random access procedure in a downlink data channel transmission set during a contention resolution window associated with the random access procedure, the first downlink data channel transmission carrying a contention resolution MAC-CE. The feedback component 1030 may receive acknowledgment information regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0287] The message component 1020 can receive a random access message associated with a random access procedure from a UE, wherein HARQ feedback is disabled for the random access procedure. The window component 1025 can determine a contention resolution window associated with the random access procedure for a first downlink data channel transmission associated with the random access procedure in a downlink data channel transmission set, the first downlink data channel transmission carrying a contention resolution MAC-CE. The feedback component 1030 can receive acknowledgment information regarding the first downlink data channel transmission carrying the contention resolution MAC-CE based on transmitting an indication to the UE that HARQ feedback is to be enabled.

[0288] The message component 1020 can receive a random access message associated with a random access procedure from a UE, wherein HARQ feedback is disabled for the random access procedure. The window component 1025 can determine a contention resolution window associated with the random access procedure for a downlink data channel transmission carrying a contention resolution MAC-CE. The feedback component 1030 can refrain from receiving acknowledgment information regarding a downlink data channel transmission carrying a random access response message including a contention resolution MAC-CE based on the disabled HARQ feedback.

[0289] The transmitter 1035 can transmit signals generated by other components of the device 1005. In some examples, the transmitter 1035 can be co-located with the receiver 1010 in a transceiver module. For example, the transmitter 1035 can be a reference Figure 12 Examples of aspects of the described transceiver 1220. The transmitter 1035 may utilize a single antenna or a collection of antennas.

[0290] Figure 11 A block diagram 1100 of a base station communication manager 1105 is shown in accordance with one or more aspects of the present disclosure. The base station communication manager 1105 can be an example of aspects of the base station communication manager 915, the base station communication manager 1015, or the base station communication manager 1210 described herein. The base station communication manager 1105 can include a messaging component 1110, a window component 1115, and a feedback component 1120. Each of these modules can communicate with each other directly or indirectly (e.g., via one or more buses).

[0291] The message component 1110 can receive, from a UE, a random access message associated with a random access procedure, wherein HARQ feedback is disabled for the random access procedure, and wherein a contention resolution window is associated with the random access procedure for downlink data channel transmissions associated with the random access procedure in a downlink data channel transmission set. The window component 1115 can transmit the downlink data channel transmission during the contention resolution window, the downlink data channel transmission carrying a contention resolution MAC-CE.

[0292] The message component 1110 may receive a random access message associated with a random access procedure from a UE and may transmit a configuration regarding a contention resolution timer. The window component 1115 may transmit, based on the configuration regarding the contention resolution timer, a first downlink data channel transmission associated with the random access procedure in a downlink data channel transmission set during a contention resolution window associated with the random access procedure, the first downlink data channel transmission carrying a contention resolution MAC-CE. The feedback component 1120 may receive acknowledgment information regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0293] The message component 1110 may receive, from the UE, a random access message associated with a random access procedure for which HARQ feedback is disabled. In some examples, the message component 1110 may receive, from the UE, a random access message associated with a random access procedure for which HARQ feedback is disabled. In some examples, the message component 1110 may include the indication in UE context information. In some examples, the message component 1110 may receive, in the random access message, a request to enable HARQ feedback for the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0294] In some examples, message component 1110 may transmit an indication in a contention resolution MAC-CE. In some examples, message component 1110 may transmit a DCI message scheduling a first downlink data channel transmission carrying the contention resolution MAC-CE, wherein the DCI message includes an indication that HARQ feedback is to be enabled. In some examples, message component 1110 may receive an RRC message indicating a failure of contention resolution associated with the random access procedure. In some examples, message component 1110 may transmit a configuration including an indication of a number of repetitions associated with the downlink data channel transmission carrying the contention resolution MAC-CE. In some examples, message component 1110 may transmit a downlink control channel carrying a DCI message scheduling one or more transport blocks associated with the number of repetitions associated with the downlink data channel transmission carrying the contention resolution MAC-CE.

[0295] In some cases, the indication includes a bit indication. In some cases, the bit indication includes a reserved bit in a MAC-CE of a contention resolution MAC-CE. In some cases, the base station is a non-terrestrial base station, including a satellite or a high-altitude platform station in a non-terrestrial network. In some cases, the contention resolution MAC-CE includes a contention resolution identifier. In some cases, the random access message includes msg3.

[0296] The window component 1115 can determine a contention resolution window associated with the random access procedure for a first downlink data channel transmission associated with the random access procedure in a set of downlink data channel transmissions, the first downlink data channel transmission carrying a contention resolution MAC-CE. In some examples, the window component 1115 can determine a contention resolution window associated with the random access procedure for a downlink data channel transmission carrying a contention resolution MAC-CE. In some cases, the contention resolution window includes one or more DRX cycles. In some cases, the contention resolution window includes one or more DRX cycles.

[0297] Feedback component 1120 may receive acknowledgment information regarding a first downlink data channel transmission carrying the contention resolution MAC-CE based on transmitting an indication to the UE that HARQ feedback is to be enabled. In some examples, feedback component 1120 may suppress receiving acknowledgment information regarding a downlink data channel transmission carrying a random access response message including the contention resolution MAC-CE based on the disabled HARQ feedback. In some examples, feedback component 1120 may receive acknowledgment information based on the elapse of a contention resolution window, the acknowledgment information comprising a negative acknowledgment. In some cases, the random access message comprises msg3. In some cases, feedback component 1120 may transmit a DCI message scheduling resources associated with an uplink control channel, wherein receiving the acknowledgment information comprises receiving acknowledgment information on the uplink control information using the scheduled resources. In some cases, the acknowledgment information comprises a positive acknowledgment or a negative acknowledgment.

[0298] Figure 12 A diagram of a system 1200 including a device 1205 according to one or more aspects of the present disclosure is shown. The device 1205 may be an example of, or include components of, the device 905, device 1005, or base station 105 described herein. The device 1205 may include components for two-way voice and data communications, including components for transmitting and receiving communications, including a base station communications manager 1210, a network communications manager 1215, a transceiver 1220, an antenna 1225, a memory 1230, a processor 1240, and an inter-station communications manager 1245. These components may be in electronic communication via one or more buses (e.g., bus 1250).

[0299] The base station communication manager 1210 may receive a random access message associated with a random access procedure from a UE, wherein HARQ feedback is disabled for the random access procedure, and wherein a contention resolution window is associated with the random access procedure for downlink data channel transmissions associated with the random access procedure in a downlink data channel transmission set; and transmit the downlink data channel transmission during the contention resolution window, the downlink data channel transmission carrying a contention resolution MAC-CE.

[0300] The base station communication manager 1210 may receive a random access message associated with a random access procedure from a UE; transmit a configuration regarding a contention resolution timer; transmit a first downlink data channel transmission associated with the random access procedure in a downlink data channel transmission set during a contention resolution window associated with the random access procedure based on the configuration regarding the contention resolution timer transmitted, the first downlink data channel transmission carrying a contention resolution MAC-CE; and receive confirmation information regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0301] The base station communication manager 1210 may also receive a random access message associated with a random access procedure from the UE, wherein HARQ feedback is disabled for the random access procedure; determine a contention resolution window associated with the random access procedure for a first downlink data channel transmission associated with the random access procedure in a downlink data channel transmission set, the first downlink data channel transmission carrying a contention resolution MAC-CE; and receive acknowledgment information about the first downlink data channel transmission carrying the contention resolution MAC-CE based on transmitting an indication to the UE that HARQ feedback is to be enabled.

[0302] The base station communication manager 1210 may also receive a random access message associated with a random access procedure from the UE, wherein HARQ feedback is disabled for the random access procedure; determine a contention resolution window associated with the random access procedure for downlink data channel transmission carrying a contention resolution MAC-CE; and suppress receiving acknowledgment information about a downlink data channel transmission carrying a random access response message including the contention resolution MAC-CE based on the disabled HARQ feedback.

[0303] By including or configuring the base station communication manager 1210 according to the examples described herein, the device 1205 can provide improvements to random access procedures. For example, by supporting early contention resolution operations, the device 1205 can facilitate improvements in efficiency and resource usage of random access operations, and in some examples can facilitate spectrum efficiency, reduced latency, reduced power consumption, and improved coordination between the UE and the device 1205, among other benefits.

[0304] The network communications manager 1215 may manage communications with the core network (eg, via one or more wired backhaul links). For example, the network communications manager 1215 may manage the delivery of data communications for client devices, such as one or more UEs 115.

[0305] The transceiver 1220 can communicate bidirectionally via one or more antennas, wired or wireless links, as described above. For example, the transceiver 1220 can represent a wireless transceiver and can communicate bidirectionally with another wireless transceiver. The transceiver 1220 can also include a modem to modulate packets and provide the modulated packets to the antenna for transmission, as well as demodulate packets received from the antenna. In some cases, the device 1205 may include a single antenna 1225. However, in some cases, the device 1205 may have more than one antenna 1225, which may be capable of concurrently transmitting or receiving multiple wireless transmissions.

[0306] The memory 1230 may include RAM, ROM, or a combination thereof. The memory 1230 may store computer-readable code 1235 including instructions that, when executed by a processor (e.g., processor 1240), cause the device to perform the various functions described herein. In some cases, the memory 1230 may include, among other things, a basic I / O system (BIOS), which may control basic hardware or software operations, such as interaction with peripheral components or devices.

[0307] The code 1235 may include instructions for implementing various aspects of the present disclosure, including instructions for supporting wireless communications. The code 1235 may be stored in a non-transitory computer-readable medium, such as system memory or other types of memory. In some cases, the code 1235 may not be directly executed by the processor 1240, but may cause a computer (e.g., when compiled and executed) to perform the functions described herein.

[0308] The processor 1240 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, discrete gate or transistor logic components, discrete hardware components, or any combination thereof). In some cases, the processor 1240 may be configured to operate a memory array using a memory controller. In some cases, the memory controller may be integrated into the processor 1240. The processor 1240 may be configured to execute computer-readable instructions stored in a memory (e.g., memory 1230) to cause the device 1205 to perform various functions (e.g., functions or tasks supporting contention resolution in a new radio non-terrestrial network).

[0309] The inter-site communication manager 1245 can manage communications with other base stations 105 and can include a controller or scheduler for controlling communications with the UE 115 in coordination with the other base stations 105. For example, the inter-site communication manager 1245 can coordinate the scheduling of transmissions to the UE 115 for various interference mitigation techniques, such as beamforming or joint transmission. In some examples, the inter-site communication manager 1245 can provide an X2 interface within an LTE / LTE-A wireless communication network technology to provide communications between the base stations 105.

[0310] Figure 13 13. A flow chart illustrating a method 1300 according to one or more aspects of the present disclosure is shown. The operations of the method 1300 may be implemented by the UE 115 or components thereof as described herein. For example, the operations of the method 1300 may be implemented by the UE 115 or components thereof as described herein. Figures 5 to 8 In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the following functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the following functions.

[0311] At 1305, the UE may optionally determine that HARQ feedback is disabled. The operations of 1305 may be performed according to the methods described herein. In some examples, aspects of the operations of 1305 may be as described with reference to Figures 5 to 8 Describes the message component to execute.

[0312] At 1310, the UE may transmit a random access message associated with a random access procedure to the base station based on determining that the HARQ feedback is disabled. The operations of 1310 may be performed according to the methods described herein. In some examples, aspects of the operations of 1310 may be as described with reference to Figures 5 to 8 Describes the message component to execute.

[0313] At 1315, the UE may initiate a contention resolution window associated with the random access procedure for downlink data channel transmissions associated with the random access procedure in the downlink data channel transmission set. The operations of 1315 may be performed according to the methods described herein. In some examples, aspects of the operations of 1315 may be as described with reference to Figures 5 to 8 The described window component is executed.

[0314] At 1320, the UE may receive the downlink data channel transmission during the contention resolution window, the downlink data channel transmission carrying the contention resolution MAC-CE. The operations of 1320 may be performed according to the methods described herein. In some examples, aspects of the operations of 1320 may be as described with reference to Figures 5 to 8 The described window component is executed.

[0315] Figure 14 1400 according to one or more aspects of the present disclosure. The operations of the method 1400 may be implemented by the base station 105 or its components as described herein. For example, the operations of the method 1400 may be implemented by the base station 105 or its components as described herein. Figures 9 to 12 In some examples, a base station may execute an instruction set to control functional elements of the base station to perform the functions described below. Additionally or alternatively, the base station may use dedicated hardware to perform various aspects of the functions described below.

[0316] At 1405, the base station may receive a random access message associated with a random access procedure from a UE, wherein HARQ feedback is disabled for the random access procedure, and wherein a contention resolution window is associated with the random access procedure for downlink data channel transmissions associated with the random access procedure in a downlink data channel transmission set. The operations of 1405 may be performed according to the methods described herein. In some examples, aspects of the operations of 1405 may be performed as described with reference to Figures 9 to 12 Describes the message component to execute.

[0317] At 1410, the base station may transmit the downlink data channel transmission during the contention resolution window, the downlink data channel transmission carrying the contention resolution MAC-CE. The operations of 1410 may be performed according to the methods described herein. In some examples, aspects of the operations of 1410 may be as described with reference to Figures 9 to 12 The described window component is executed.

[0318] Figure 15 15. A flow chart illustrating a method 1500 according to one or more aspects of the present disclosure is shown. The operations of the method 1500 may be implemented by the UE 115 or its components as described herein. For example, the operations of the method 1500 may be implemented by the UE 115 or its components as described herein. Figures 5 to 8 In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the following functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the following functions.

[0319] At 1505, the UE may determine that HARQ feedback is disabled for the random access procedure. The operations of 1505 may be performed according to the methods described herein. In some examples, aspects of the operations of 1505 may be as described with reference to Figures 5 to 8 Describes the message component to execute.

[0320] At 1510, the UE may transmit a random access message associated with the random access procedure to the base station based on determining that HARQ feedback is disabled for the random access procedure. The operations of 1510 may be performed according to the methods described herein. In some examples, aspects of the operations of 1510 may be as described with reference to Figures 5 to 8 Describes the message component to execute.

[0321] At 1515, the UE may refrain from transmitting acknowledgment information regarding a downlink data channel transmission carrying a random access response message including a contention resolution MAC-CE based on the disabled HARQ feedback. The operations of 1515 may be performed according to the methods described herein. In some examples, aspects of the operations of 1515 may be as described with reference to Figures 5 to 8 Describes the feedback component to perform.

[0322] Figure 16 1600 according to one or more 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 implemented by a UE or its components as described herein. Figures 5 to 8 In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0323] At 1605, the method may include transmitting a random access message associated with a random access procedure to a base station. The operations of 1605 may be performed according to the examples disclosed herein. In some examples, aspects of the operations of 1605 may be performed as described with reference to Figures 5 to 8 Describes the message component to execute.

[0324] At 1610, the method may include receiving a configuration regarding a contention resolution timer. The operations of 1610 may be performed according to the examples disclosed herein. In some examples, aspects of the operations of 1610 may be as described with reference to Figures 5 to 8 The described timer component is used to perform the

[0325] At 1615, the method may include setting a value of a contention resolution timer based on the configuration. The operations of 1615 may be performed according to the examples disclosed herein. In some examples, aspects of the operations of 1615 may be as described with reference to Figures 5 to 8 The described timer component is used to perform the

[0326] At 1620, the method may include monitoring a contention resolution window associated with the random access procedure based on a value of a contention resolution timer set to find a first downlink data channel transmission associated with the random access procedure in a downlink data channel transmission set, the first downlink data channel transmission carrying a contention resolution MAC-CE. The operations of 1620 may be performed according to examples disclosed herein. In some examples, aspects of the operations of 1620 may be performed as described with reference to Figures 5 to 8 The described window component is executed.

[0327] At 1625, the method may include transmitting an acknowledgment regarding the first downlink data channel transmission carrying the contention resolution MAC-CE. The operations of 1625 may be performed according to the examples disclosed herein. In some examples, aspects of the operations of 1625 may be performed as described with reference to Figures 5 to 8 Describes the feedback component to perform.

[0328] Figure 17 1700 according to one or more aspects of the present disclosure. The operations of the method 1700 may be implemented by the base station 105 or its components as described herein. For example, the operations of the method 1700 may be implemented by the base station 105 or its components as described herein. Figures 9 to 12 The base station communications manager described herein may be used to perform the functions described herein. In some examples, a base station may execute an instruction set to control functional elements of the base station to perform the functions described herein. Additionally or alternatively, a base station may use dedicated hardware to perform various aspects of the functions described herein.

[0329] At 1705, the method may include receiving a random access message associated with a random access procedure from the UE. The operations of 1705 may be performed according to the examples disclosed herein. In some examples, aspects of the operations of 1705 may be performed as described with reference to Figures 9 to 12 Describes the message component to execute.

[0330] At 1710, the method may include transmitting a configuration regarding a contention resolution timer. The operations of 1710 may be performed according to examples disclosed herein. In some examples, aspects of the operations of 1710 may be as described with reference to Figures 9 to 12 Describes the message component to execute.

[0331] At 1715, the method may include transmitting a first downlink data channel transmission from a set of multiple downlink data channel transmissions associated with the random access procedure during a contention resolution window associated with the random access procedure based on transmitting a configuration regarding a contention resolution timer, the first downlink data channel transmission carrying a contention resolution MAC-CE. The operations of 1715 may be performed according to examples disclosed herein. In some examples, aspects of the operations of 1715 may be performed as described with reference to Figures 9 to 12 Describes the window component to execute.

[0332] At 1720, the method may include receiving an acknowledgment regarding the first downlink data channel transmission carrying the contention resolution MAC-CE. The operations of 1720 may be performed according to the examples disclosed herein. In some examples, aspects of the operations of 1720 may be performed as described with reference to Figures 9 to 12 Describes the feedback component to perform.

[0333] Figure 181800 according to one or more aspects of the present disclosure. The operations of the method 1800 may be implemented by the UE 115 or its components as described herein. For example, the operations of the method 1800 may be implemented by the UE 115 or its components as described herein. Figures 5 to 8 In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the following functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the following functions.

[0334] At 1805, the UE may transmit a random access message associated with a random access procedure to a base station, wherein HARQ feedback is disabled for the random access procedure. The operations of 1805 may be performed according to the methods described herein. In some examples, aspects of the operations of 1805 may be as described with reference to Figures 5 to 8 Describes the message component to execute.

[0335] At 1810, the UE may monitor a contention resolution window associated with the random access procedure to find a first downlink data channel transmission associated with the random access procedure in a downlink data channel transmission set, the first downlink data channel transmission carrying a contention resolution MAC-CE. The operations of 1810 may be performed according to the methods described herein. In some examples, aspects of the operations of 1810 may be as described with reference to Figures 5 to 8 Describes the window component to execute.

[0336] At 1815, the UE may transmit an acknowledgment regarding the first downlink data channel transmission carrying the contention resolution MAC-CE based on the indication that HARQ feedback is to be enabled. The operations of 1815 may be performed according to the methods described herein. In some examples, aspects of the operations of 1815 may be as described with reference to Figures 5 to 8 Describes the feedback component to perform.

[0337] Figure 19 1900 according to one or more aspects of the present disclosure. The operations of the method 1900 may be implemented by the base station 105 or its components as described herein. For example, the operations of the method 1900 may be implemented by the base station 105 or its components as described herein. Figures 9 to 12 In some examples, a base station may execute an instruction set to control functional elements of the base station to perform the functions described below. Additionally or alternatively, the base station may use dedicated hardware to perform various aspects of the functions described below.

[0338] At 1905, the base station may receive a random access message associated with a random access procedure from the UE, wherein HARQ feedback is disabled for the random access procedure. The operations of 1905 may be performed according to the methods described herein. In some examples, aspects of the operations of 1905 may be as described with reference to Figures 9 to 12 Describes the message component to execute.

[0339] At 1910, the base station may determine a contention resolution window associated with the random access procedure for a first downlink data channel transmission associated with the random access procedure in a downlink data channel transmission set, the first downlink data channel transmission carrying a contention resolution MAC-CE. The operations of 1910 may be performed according to the methods described herein. In some examples, aspects of the operations of 1910 may be performed as described with reference to Figures 9 to 12 Describes the window component to execute.

[0340] At 1915, the base station may receive an acknowledgment regarding the first downlink data channel transmission carrying the contention resolution MAC-CE based on transmitting an indication to the UE that HARQ feedback is to be enabled. The operations of 1915 may be performed according to the methods described herein. In some examples, aspects of the operations of 1915 may be as described with reference to Figures 9 to 12 Describes the feedback component to perform.

[0341] Figure 20 1. A flow chart illustrating a method 2000 according to one or more aspects of the present disclosure is shown. The operations of the method 2000 may be implemented by the UE 115 or its components as described herein. For example, the operations of the method 2000 may be implemented by the UE 115 or its components as described herein. Figures 5 to 8 In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the following functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the following functions.

[0342] At 2005, the UE may transmit a random access message associated with a random access procedure to the base station, wherein HARQ feedback is disabled for the random access procedure. The operations of 2005 may be performed according to the methods described herein. In some examples, aspects of the operations of 2005 may be as described with reference to Figures 5 to 8 Describes the message component to execute.

[0343] At 2010, the UE may monitor the contention resolution window associated with the random access procedure to find a downlink data channel transmission carrying a contention resolution MAC-CE. The operations of 2010 may be performed according to the methods described herein. In some examples, aspects of the operations of 2010 may be as described with reference to Figures 5 to 8 Describes the window component to execute.

[0344] At 2015, the UE may optionally refrain from transmitting an acknowledgment of a downlink data channel transmission carrying a random access response message including the contention resolution MAC-CE based on the disabled HARQ feedback. The operations of 2015 may be performed according to the methods described herein. In some examples, aspects of the operations of 2015 may be performed as described with reference to Figures 5 to 8 Describes the feedback component to perform.

[0345] Figure 21 2. A flow chart illustrating a method 2100 according to one or more aspects of the present disclosure is shown. The operations of the method 2100 may be implemented by the base station 105 or its components as described herein. For example, the operations of the method 2100 may be implemented by the base station 105 or its components as described herein. Figures 9 to 12 In some examples, a base station may execute an instruction set to control functional elements of the base station to perform the functions described below. Additionally or alternatively, the base station may use dedicated hardware to perform various aspects of the functions described below.

[0346] At 2105, the base station may receive a random access message associated with a random access procedure from the UE, wherein HARQ feedback is disabled for the random access procedure. The operations of 2105 may be performed according to the methods described herein. In some examples, aspects of the operations of 2105 may be as described with reference to Figures 9 to 12 Describes the message component to execute.

[0347] At 2110, the base station may determine a contention resolution window associated with the random access procedure for downlink data channel transmission carrying a contention resolution MAC-CE. The operations of 2110 may be performed according to the methods described herein. In some examples, aspects of the operations of 2110 may be as described with reference to Figures 9 to 12 The described window component is executed.

[0348] At 2115, the base station may optionally suppress receiving acknowledgment information regarding a downlink data channel transmission carrying a random access response message including the contention resolution MAC-CE based on the disabled HARQ feedback. The operations of 2115 may be performed according to the methods described herein. In some examples, various aspects of the operations of 2115 may be performed as described with reference to Figures 9 to 12 Describes the feedback component to perform.

[0349] Figure 22 2200 according to one or more aspects of the present disclosure. The operations of the method 2200 may be implemented by the UE 115 or its components as described herein. For example, the operations of the method 2200 may be implemented by the UE 115 or its components as described herein. Figures 5 to 8In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the following functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the following functions.

[0350] At 2205, the UE may transmit a random access message associated with a random access procedure to the base station. The operations of 2205 may be performed according to the methods described herein. In some examples, aspects of the operations of 2205 may be as described with reference to Figures 5 to 8 Describes the message component to execute.

[0351] At 2210, the UE may determine that HARQ feedback is disabled for the random access procedure. The operations of 2210 may be performed according to the methods described herein. In some examples, aspects of the operations of 2210 may be as described with reference to Figures 5 to 8 The described window component is executed.

[0352] At 2215, the UE may refrain from transmitting acknowledgment information regarding a downlink data channel transmission carrying a random access response message including one or more of a contention resolution MAC-CE or an SDU associated with a downlink shared control channel, or both, based on the disabled HARQ feedback. The operations of 2215 may be performed according to the methods described herein. In some examples, aspects of the operations of 2215 may be as described with reference to Figures 5 to 8 Describes the feedback component to perform.

[0353] Figure 23 23. The operations of the method 2300 may be implemented by the UE 115 or its components as described herein. For example, the operations of the method 2300 may be implemented by the UE 115 or its components as described herein. Figures 5 to 8 In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the following functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the following functions.

[0354] At 2305, the UE may transmit a random access message associated with a random access procedure to the base station. The operations of 2305 may be performed according to the methods described herein. In some examples, aspects of the operations of 2305 may be as described with reference to Figures 5 to 8 Describes the message component to execute.

[0355] At 2310, the UE may receive a random access response message associated with the random access procedure, the random access response message including a timing advance. The operations of 2310 may be performed according to the methods described herein. In some examples, aspects of the operations of 2310 may be as described with reference to Figures 5 to 8 Describes the message component to execute.

[0356] At 2315, the UE may optionally determine that HARQ feedback is disabled for the random access procedure. The operations of 2315 may be performed according to the methods described herein. In some examples, aspects of the operations of 2315 may be as described with reference to Figures 5 to 8 Describes the feedback component to perform.

[0357] At 2320, the UE may optionally control the uplink alignment timer based on the timing advance or the disabled HARQ feedback, or both. The operations of 2320 may be performed according to the methods described herein. In some examples, aspects of the operations of 2320 may be as described with reference to Figures 5 to 8 The described timer component is used to perform the

[0358] Figure 24 24. A flow chart illustrating a method 2400 according to one or more aspects of the present disclosure is shown. The operations of the method 2400 may be implemented by the UE 115 or components thereof as described herein. For example, the operations of the method 2400 may be implemented by the UE 115 or components thereof as described herein. Figures 5 to 8 In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the following functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the following functions.

[0359] At 2405, the UE may transmit a random access message associated with a random access procedure to the base station. The operations of 2405 may be performed according to the methods described herein. In some examples, aspects of the operations of 2405 may be performed as described with reference to Figures 5 to 8 Describes the message component to execute.

[0360] At 2410, the UE may monitor the contention resolution window associated with the random access procedure to find the first downlink data channel transmission associated with the random access procedure in the downlink data channel transmission set, the first downlink data channel transmission carrying the contention resolution MAC-CE. The operations of 2410 may be performed according to the methods described herein. In some examples, aspects of the operations of 2410 may be as described with reference to Figures 5 to 8 The described window component is executed.

[0361] At 2415, the UE may optionally transmit an acknowledgment regarding the first downlink data channel transmission carrying the contention resolution MAC-CE. The operations of 2415 may be performed according to the methods described herein. In some examples, aspects of the operations of 2415 may be as described with reference to Figures 5 to 8 Describes the feedback component to perform.

[0362] It should be noted that the methods described herein describe possible implementations, and that the operations and steps may be rearranged or otherwise modified and other implementations are possible. Furthermore, aspects from two or more methods may be combined.

[0363] The following provides an overview of various aspects of the disclosure:

[0364] Aspect 1: A method for wireless communication at a UE, comprising: determining that HARQ feedback is disabled; transmitting a random access message associated with a random access procedure to a base station based at least in part on determining that the HARQ feedback is disabled; initiating a contention resolution window associated with the random access procedure for a downlink data channel transmission associated with the random access procedure among a plurality of downlink data channel transmissions; and receiving the downlink data channel transmission during the contention resolution window, the downlink data channel transmission carrying a contention resolution MAC-CE.

[0365] Aspect 2: The method of aspect 1, wherein the random access message includes msg3.

[0366] Aspect 3: The method of any one of aspects 1 to 2, further comprising: transmitting an acknowledgment information regarding the downlink data channel transmission carrying the contention resolution MAC-CE based at least in part on an indication that HARQ feedback for the random access procedure is to be enabled.

[0367] Aspect 4: The method of Aspect 3 further includes: identifying an indication to enable the HARQ feedback based at least in part on UE context information, a network configuration for enabling HARQ feedback, or a default configuration for enabling HARQ feedback; and enabling the HARQ feedback based at least in part on the identification.

[0368] Aspect 5: The method according to any one of aspects 3 to 4, further comprising: transmitting, in the random access message, a request to enable HARQ feedback for downlink data channel transmission carrying the contention resolution MAC-CE.

[0369] Aspect 6: The method of any one of aspects 3 or 5, further comprising: receiving an indication in a contention resolution MAC-CE; and enabling HARQ feedback based at least in part on the indication in the contention resolution MAC-CE.

[0370] Aspect 7: The method according to any one of Aspects 3 or 6, further comprising: receiving a DCI message scheduling downlink data channel transmission carrying the contention resolution MAC-CE, wherein the DCI message includes an indication that the HARQ feedback is to be enabled.

[0371] Aspect 8: A method as in any one of Aspects 3 to 7, wherein resources associated with the uplink control channel are determined at least in part based on a second indication in a contention resolution MAC-CE, wherein the second indication includes a new MAC-CE providing uplink control channel resources, and wherein transmitting the acknowledgment information includes: transmitting the acknowledgment information on the uplink control channel using the determined resources.

[0372] Aspect 9: The method of aspect 8, wherein the logical channel identifier of the new MAC-CE is the same as or different from that of the contention resolution MAC-CE.

[0373] Aspect 10: The method of aspect 3 further comprises: determining a reception failure of a downlink data channel transmission carrying the contention resolution MAC-CE, wherein HARQ feedback is enabled for the random access procedure and the acknowledgment information comprises a negative acknowledgment.

[0374] Aspect 11: The method of any one of aspects 3 to 11, wherein transmitting the acknowledgment information comprises transmitting the acknowledgment information based at least in part on a contention resolution window elapse, wherein HARQ feedback is enabled for the random access procedure, and the acknowledgment information comprises a negative acknowledgment.

[0375] Aspect 12: The method of any one of aspects 1 to 12, further comprising: receiving an RRC message including an indication to disable HARQ feedback for the random access procedure, wherein determining that the HARQ feedback is disabled is based at least in part on receiving the RRC message.

[0376] Aspect 13: The method of any one of Aspects 1 to 13 further includes: receiving a random access response message associated with the random access procedure, the random access response message including a timing advance; and controlling the uplink alignment timer at least in part based on the timing advance or the disabled HARQ feedback for the random access procedure, or both.

[0377] Aspect 14: The method of any one of Aspects 1 to 13, wherein the base station is a non-terrestrial base station including a satellite or a high altitude platform station in a non-terrestrial network.

[0378] Aspect 15: A method for wireless communication at a base station, comprising: receiving a random access message associated with a random access procedure from a UE, wherein HARQ feedback is disabled, and wherein a contention resolution window is associated with the random access procedure for a downlink data channel transmission associated with the random access procedure among a plurality of downlink data channel transmissions; and transmitting the downlink data channel transmission during the contention resolution window, the downlink data channel transmission carrying a contention resolution MAC-CE.

[0379] Aspect 16: The method of Aspect 15 further includes: transmitting an indication to the UE to enable the HARQ feedback; and receiving confirmation information about the downlink data channel transmission carrying the contention resolution MAC-CE based at least in part on the transmitted indication to enable the HARQ feedback.

[0380] Aspect 17: The method of Aspect 16 further comprises: transmitting an indication in the contention resolution MAC-CE.

[0381] Aspect 18: A method for wireless communication at a UE, comprising: determining that HARQ feedback is disabled for a random access procedure; transmitting a random access message associated with the random access procedure to a base station based at least in part on determining that HARQ feedback is disabled for the random access procedure; and suppressing transmission of acknowledgment information regarding a downlink data channel transmission carrying a random access response message including a contention resolution MAC-CE based at least in part on the disabled HARQ feedback.

[0382] Aspect 19: The method of Aspect 18, wherein the random access message includes msg3.

[0383] Aspect 20: The method according to any one of aspects 18 to 19, further comprising: monitoring a contention resolution window associated with the random access procedure for a number of repetitions associated with a downlink data channel transmission carrying the contention resolution MAC-CE.

[0384] Aspect 21: The method of aspect 20, further comprising: receiving a configuration including an indication of a number of repetitions associated with a downlink data channel transmission carrying the contention resolution MAC-CE.

[0385] Aspect 22: The method of any one of Aspects 20 to 21 further comprises: receiving a downlink control channel carrying a DCI message, the DCI message scheduling one or more transport blocks associated with a number of repetitions of a downlink data channel transmission associated with carrying the contention resolution MAC-CE.

[0386] Aspect 23: The method of any one of Aspects 20 to 22, further comprising: starting a contention resolution timer associated with the contention resolution window, wherein monitoring the contention resolution window is based at least in part on the contention resolution timer.

[0387] Aspect 24: The method according to any one of aspects 18 to 23, wherein the random access response message further includes an SDU associated with a downlink shared control channel.

[0388] Aspect 25: A method for wireless communication at a UE, comprising: transmitting a random access message associated with a random access procedure to a base station; receiving a configuration regarding a contention resolution timer; setting a value of the contention resolution timer based at least in part on the configuration; monitoring a contention resolution window associated with the random access procedure to search for a first downlink data channel transmission associated with the random access procedure among multiple downlink data channel transmissions based at least in part on setting the value of the contention resolution timer, the first downlink data channel transmission carrying a contention resolution MAC-CE; and transmitting acknowledgment information regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0389] Aspect 26: The method of Aspect 25 further includes: receiving a DCI message that schedules a second downlink data channel transmission carrying a second contention resolution MAC-CE among the multiple downlink data channel transmissions, wherein the DCI message includes an indication of disabling HARQ feedback for the second downlink data channel transmission.

[0390] Aspect 27: A method as in any of Aspects 25 to 26, wherein the value of the contention resolution timer is based at least in part on one or more of: a maximum propagation delay between the UE and the base station, a duration of a transmission time interval associated with transmission of a contention resolution identifier, or a gap between downlink data channel reception and uplink control channel transmission, or a combination thereof.

[0391] Aspect 28: The method of any one of Aspects 25 to 27, wherein transmitting the acknowledgment information comprises transmitting the acknowledgment information based at least in part on the contention resolution window elapse, the acknowledgment information comprising a negative acknowledgment.

[0392] Aspect 29: A method for wireless communication at a base station, comprising: receiving a random access message associated with a random access procedure from a UE; transmitting a configuration regarding a contention resolution timer; transmitting a first downlink data channel transmission associated with the random access procedure from a set of downlink data channel transmissions during a contention resolution window associated with the random access procedure based at least in part on transmitting the configuration regarding the contention resolution timer, the first downlink data channel transmission carrying a contention resolution MAC-CE; and receiving acknowledgment information regarding the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0393] Aspect 30: The method of Aspect 29 further includes: transmitting a DCI message scheduling a second downlink data channel transmission carrying a second contention resolution MAC-CE among the multiple downlink data channel transmissions, wherein the DCI message includes an indication of disabling HARQ feedback for the second downlink data channel transmission.

[0394] Aspect 31: A method for wireless communication at a UE, comprising: transmitting a random access message associated with a random access procedure to a base station, wherein HARQ feedback is disabled for the random access procedure; monitoring a contention resolution window associated with the random access procedure to find a first downlink data channel transmission associated with the random access procedure among multiple downlink data channel transmissions, the first downlink data channel transmission carrying a contention resolution MAC-CE; and transmitting confirmation information about the first downlink data channel transmission carrying the contention resolution MAC-CE based at least in part on an indication to enable the HARQ feedback.

[0395] Aspect 32: The method of Aspect 31, wherein the random access message includes msg3.

[0396] Aspect 33: The method of aspect 31 or 32 further comprises: identifying, in the UE context information, an indication that the HARQ feedback is to be enabled; and enabling the HARQ feedback based at least in part on the indication.

[0397] Aspect 34: The method of any one of aspects 31 to 33, further comprising: transmitting, in the random access message, a request to enable HARQ feedback for the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0398] Aspect 35: The method of any one of aspects 31 to 34, further comprising: receiving an indication in a contention resolution MAC-CE; and enabling HARQ feedback based at least in part on the indication in the contention resolution MAC-CE.

[0399] Aspect 36: The method of Aspect 35, wherein the indication comprises a bit indication.

[0400] Aspect 37: The method of aspect 36, wherein the bit indicates a reserved bit in a MAC subheader including the contention resolution MAC-CE.

[0401] Aspect 38: The method of any one of aspects 31 to 37, further comprising: receiving a DCI message scheduling a first downlink data channel transmission carrying the contention resolution MAC-CE, wherein the DCI message includes an indication that the HARQ feedback is to be enabled.

[0402] Aspect 39: A method as in any one of Aspects 31 to 38, wherein resources associated with an uplink control channel are determined at least in part based on a second indication in the contention resolution MAC-CE, and wherein transmitting the acknowledgment information comprises transmitting the acknowledgment information on the uplink control channel using the determined resources.

[0403] Aspect 40: The method of aspect 39, wherein the second indication comprises a new MAC-CE providing uplink control channel resources.

[0404] Aspect 41: The method of aspect 40, wherein the logical channel identifier of the MAC-CE is the same as or different from that of the contention resolution MAC-CE.

[0405] Aspect 42: The method of Aspect 39, wherein the resource is adjacent to the end of the contention resolution window.

[0406] Aspect 43: The method of any one of aspects 31 to 42, wherein a DCI message scheduling resources associated with an uplink control channel is received, wherein transmitting the acknowledgment information comprises transmitting the acknowledgment information on the uplink control channel using the scheduled resources.

[0407] Aspect 44: The method of Aspect 43 further comprises: determining the scheduled resources based at least in part on one or more resource indices in the DCI message, the one or more resource indices corresponding to the scheduled resources.

[0408] Aspect 45: The method of any one of Aspects 31 to 44, further comprising: determining a reception failure of the first downlink data channel transmission carrying the contention resolution MAC-CE, wherein the HARQ feedback is enabled for the random access procedure and the acknowledgment information includes a negative acknowledgment.

[0409] Aspect 46: The method of aspect 31, wherein transmitting the acknowledgment information comprises transmitting the acknowledgment information based at least in part on the contention resolution window elapsed, wherein the HARQ feedback is enabled for the random access procedure, and the acknowledgment information comprises a negative acknowledgment.

[0410] Aspect 47: The method of any one of Aspects 31 to 46, further comprising: receiving a configuration regarding a contention resolution timer; and setting a value of the contention resolution timer based at least in part on the configuration.

[0411] Aspect 38: A method as in Aspect 47, wherein the value of the contention resolution timer is based at least in part on one or more of: a maximum propagation delay between the UE and the base station, a duration of a transmission time interval associated with transmission of a contention resolution identifier, or a gap between downlink data channel reception and uplink control channel transmission, or a combination thereof.

[0412] Aspect 49: The method of any one of Aspects 31 to 48, wherein the contention resolution window includes one or more DRX cycles.

[0413] Aspect 50: The method of aspect 49, wherein monitoring the contention resolution window comprises monitoring the contention resolution window during one or more active durations associated with the one or more DRX cycles.

[0414] Aspect 51: The method of any one of Aspects 31 to 50, wherein the base station is a non-terrestrial base station comprising a satellite or a high altitude platform station in a non-terrestrial network.

[0415] Aspect 52: The method of any one of aspects 31 to 51, wherein the confirmation information comprises a positive confirmation or a negative confirmation.

[0416] Aspect 53: The method of any one of Aspects 31 to 52, wherein the contention resolution MAC-CE comprises a contention resolution identifier.

[0417] Aspect 54: The method of Aspect 53, wherein the length of the contention resolution identifier in the contention resolution MAC-CE is less than or equal to the default length of the default contention resolution identifier.

[0418] Aspect 55: The method of any one of aspects 31 to 54, further comprising: transmitting an RRC message indicating a failure of contention resolution associated with the random access procedure.

[0419] Aspect 56: A method for wireless communication at a base station, comprising: receiving a random access message associated with a random access procedure from a UE, wherein HARQ feedback is disabled for the random access procedure; determining a contention resolution window associated with the random access procedure to find a first downlink data channel transmission associated with the random access procedure among a plurality of downlink data channel transmissions, the first downlink data channel transmission carrying a contention resolution MAC-CE; and receiving acknowledgment information about the first downlink data channel transmission carrying the contention resolution MAC-CE based at least in part on transmitting an indication to the UE to enable the HARQ feedback.

[0420] Aspect 57: The method of Aspect 56, wherein the random access message includes msg3.

[0421] Aspect 58: The method of aspect 56 or 57 further comprises: including the indication in UE context information.

[0422] Aspect 59: The method of any one of aspects 56 to 58, further comprising: receiving in the random access message a request to enable HARQ feedback for the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0423] Aspect 60: The method of any one of Aspects 56 to 59, further comprising: transmitting an indication in the contention resolution MAC-CE.

[0424] Aspect 61: The method of Aspect 60, wherein the indication comprises a bit indication.

[0425] Aspect 62: The method of aspect 61, wherein the bit indicates a reserved bit in a MAC-CE including the contention resolution MAC-CE.

[0426] Aspect 63: The method of any one of aspects 56 to 62, further comprising: transmitting a DCI message scheduling a first downlink data channel transmission carrying the contention resolution MAC-CE, wherein the DCI message includes an indication that the HARQ feedback is to be enabled.

[0427] Aspect 64: The method of any one of aspects 56 to 63, wherein transmitting a DCI message scheduling resources associated with an uplink control channel, wherein receiving the acknowledgment information comprises receiving the acknowledgment information on the uplink control channel using the scheduled resources.

[0428] Aspect 65: The method of any one of Aspects 56 to 64, wherein receiving the acknowledgment information comprises receiving the acknowledgment information based at least in part on the contention resolution window elapsed, the acknowledgment information comprising a negative acknowledgment.

[0429] Aspect 66: The method of any one of Aspects 56 to 65, wherein the contention resolution window includes one or more DRX cycles.

[0430] Aspect 67: The method of any one of Aspects 56 to 66, wherein the base station is a non-terrestrial base station comprising a satellite or a high altitude platform station in a non-terrestrial network.

[0431] Aspect 68: The method of any one of Aspects 56 to 67, wherein the confirmation information comprises a positive confirmation or a negative confirmation.

[0432] Aspect 69: The method of any one of Aspects 56 to 68, wherein the contention resolution MAC-CE comprises a contention resolution identifier.

[0433] Aspect 70: The method of any one of Aspects 56 to 69, further comprising: receiving an RRC message indicating a failure of contention resolution associated with the random access procedure.

[0434] Aspect 71: A method for wireless communication at a UE, comprising: transmitting a random access message associated with a random access procedure to a base station, wherein HARQ feedback is disabled for the random access procedure; monitoring a contention resolution window associated with the random access procedure to look for a downlink data channel transmission carrying a contention resolution MAC-CE; and suppressing transmission of acknowledgment information regarding a downlink data channel transmission carrying a random access response message including the contention resolution MAC-CE based at least in part on the disabled HARQ feedback.

[0435] Aspect 72: The method of Aspect 71, wherein the random access message includes msg3.

[0436] Aspect 73: The method of aspect 71 or 72, wherein monitoring the contention resolution window associated with the random access procedure comprises monitoring the contention resolution window for a number of repetitions associated with a downlink data channel transmission carrying the contention resolution MAC-CE.

[0437] Aspect 74: The method of aspect 73 further comprises: receiving a configuration including an indication of a number of repetitions associated with a downlink data channel transmission carrying the contention resolution MAC-CE.

[0438] Aspect 75: The method of aspect 73 further comprises: receiving a downlink control channel carrying a DCI message, the DCI message scheduling one or more transport blocks associated with a number of repetitions of a downlink data channel transmission associated with carrying the contention resolution MAC-CE.

[0439] Aspect 76: The method of aspect 73 further comprises: receiving a configuration regarding a contention resolution timer; and setting a value of the contention resolution timer based at least in part on the configuration.

[0440] Aspect 77: A method as in Aspect 76, wherein the value of the contention resolution timer is based at least in part on one or more of: a maximum propagation delay between the UE and the base station, a duration of a transmission time interval associated with transmission of a contention resolution identifier, or a gap between downlink data channel reception and uplink control channel transmission, or a combination thereof.

[0441] Aspect 78: The method of Aspect 73 further comprises: starting a contention resolution timer associated with the contention resolution window, wherein monitoring the contention resolution window is based at least in part on the contention resolution timer.

[0442] Aspect 79: The method of Aspect 73, wherein the contention resolution window includes one or more DRX cycles.

[0443] Aspect 80: The method of aspect 79, wherein monitoring the contention resolution window comprises monitoring the contention resolution window during one or more active durations associated with the one or more DRX cycles.

[0444] Aspect 81: The method of Aspect 73, wherein the base station is a non-terrestrial base station including a satellite or a high altitude platform station in a non-terrestrial network.

[0445] Aspect 82: A method for wireless communication at a base station, comprising: receiving a random access message associated with a random access procedure from a UE, wherein HARQ feedback is disabled for the random access procedure; determining a contention resolution window associated with the random access procedure for a downlink data channel transmission carrying a contention resolution MAC-CE; and suppressing, based at least in part on the disabled HARQ feedback, receiving acknowledgment information regarding a downlink data channel transmission carrying a random access response message including the contention resolution MAC-CE.

[0446] Aspect 83: The method of Aspect 82, wherein the random access message includes msg3.

[0447] Aspect 84: The method of aspect 82 or 83, further comprising: transmitting a configuration including an indication of a number of repetitions associated with a downlink data channel transmission carrying the contention resolution MAC-CE.

[0448] Aspect 85: The method of any one of aspects 82 to 84, further comprising: transmitting a downlink control channel carrying a DCI message, the DCI message scheduling one or more transport blocks associated with a number of repetitions associated with a downlink data channel transmission carrying the contention resolution MAC-CE.

[0449] Aspect 86: The method of any one of Aspects 82 to 85, wherein the contention resolution window includes one or more DRX cycles.

[0450] Aspect 87: The method of any one of Aspects 82 to 86, wherein the base station is a non-terrestrial base station comprising a satellite or a high altitude platform station in a non-terrestrial network.

[0451] Aspect 88: A method for wireless communication at a UE, comprising: transmitting a random access message associated with a random access procedure to a base station; determining that HARQ feedback is disabled for the random access procedure; and suppressing, based at least in part on the disabled HARQ feedback, transmitting acknowledgment information regarding a downlink data channel transmission carrying a random access response message including one or more of a contention resolution MAC-CE or an SDU associated with a downlink shared control channel, or both.

[0452] Aspect 89: The method of Aspect 88, wherein the random access message includes msg3.

[0453] Aspect 90: The method of Aspect 88 or 89 further includes: monitoring a contention resolution window associated with the random access procedure to look for a downlink data channel transmission carrying a random access response message including a contention resolution MAC-CE or an SDU associated with a downlink shared control channel, or one or more of the two.

[0454] Aspect 91: The method of any one of aspects 88 to 90, further comprising: receiving a configuration regarding a contention resolution timer; and setting a value of the contention resolution timer based at least in part on the configuration.

[0455] Aspect 92: A method as in Aspect 91, wherein the value of the contention resolution timer is based at least in part on one or more of: a maximum propagation delay between the UE and the base station, a duration of a transmission time interval associated with transmission of a contention resolution identifier, or a gap between downlink data channel reception and uplink control channel transmission, or a combination thereof.

[0456] Aspect 93: The method of any one of Aspects 88 to 92, further comprising: starting a contention resolution timer associated with a contention resolution window, wherein monitoring the contention resolution window is based at least in part on the contention resolution timer.

[0457] Aspect 94: The method of any one of Aspects 88 to 93, wherein the contention resolution window comprises one or more DRX cycles.

[0458] Aspect 95: The method of aspect 94, wherein monitoring the contention resolution window comprises monitoring the contention resolution window during one or more active durations associated with the one or more DRX cycles.

[0459] Aspect 96: The method of any one of Aspects 88 to 95, wherein the base station is a non-terrestrial base station comprising a satellite or a high altitude platform station in a non-terrestrial network.

[0460] Aspect 97: A method for wireless communication at a UE, comprising: transmitting a random access message associated with a random access procedure to a base station; receiving a random access response message associated with the random access procedure, the random access response message including a timing advance; determining that HARQ feedback is disabled for the random access procedure; and controlling an uplink alignment timer based at least in part on the timing advance or the disabled HARQ feedback, or both.

[0461] Aspect 98: The method of Aspect 97, wherein the random access message includes msg3.

[0462] Aspect 99: The method of any one of Aspects 97 to 98, further comprising: setting an uplink alignment timer based at least in part on the configuration.

[0463] Aspect 100: The method of aspect 99, further comprising: activating an uplink alignment timer based at least in part on receiving a random access response message including a timing advance.

[0464] Aspect 101: The method of aspect 99 further comprises: deactivating the uplink alignment timer based at least in part on receiving a contention resolution MAC-CE and before transmitting an acknowledgement information regarding a downlink data channel transmission carrying the contention resolution MAC-CE, or both.

[0465] Aspect 102: A method as in Aspect 99, wherein the value of the uplink alignment timer is based at least in part on one or more of: a maximum propagation delay between the UE and the base station, a duration of a transmission time interval, or a gap between downlink data channel reception and uplink control channel transmission, or a combination thereof.

[0466] Aspect 103: A method for wireless communication at a UE, comprising: transmitting a random access message associated with a random access procedure to a base station; monitoring a contention resolution window associated with the random access procedure to find a first downlink data channel transmission associated with the random access procedure among multiple downlink data channel transmissions, the first downlink data channel transmission carrying a contention resolution MAC-CE; and transmitting confirmation information about the first downlink data channel transmission carrying the contention resolution MAC-CE.

[0467] Aspect 104: The method of aspect 103, wherein the random access message includes msg3.

[0468] Aspect 105: The method of Aspect 103 or 104 further includes: determining to transmit confirmation information regarding the first downlink data channel transmission carrying the contention resolution MAC-CE, wherein transmitting the confirmation information regarding the first downlink data channel transmission carrying the contention resolution MAC-CE is at least partially based on the determination.

[0469] Aspect 106: The method of any one of Aspects 103 to 105, wherein transmitting the acknowledgment information comprises transmitting the acknowledgment information based at least in part on the contention resolution window elapse, the acknowledgment information comprising a negative acknowledgment.

[0470] Aspect 107: The method of any one of aspects 103 to 106, further comprising: receiving a configuration regarding a contention resolution timer; and setting a value of the contention resolution timer based at least in part on the configuration.

[0471] Aspect 108: The method of any one of Aspects 103 to 107, wherein the contention resolution window comprises one or more DRX cycles.

[0472] Aspect 109: The method of aspect 108, wherein monitoring the contention resolution window comprises monitoring the contention resolution window during one or more active durations associated with the one or more DRX cycles.

[0473] Aspect 110: An apparatus for wireless communication at a UE, comprising a processor and a memory coupled to the processor, the processor and the memory being configured to perform the method of any one of aspects 1 to 14.

[0474] Aspect 111: An apparatus for wireless communication at a UE, comprising at least one means for performing the method of any one of aspects 1 to 14.

[0475] Aspect 112: A non-transitory computer-readable medium storing code for wireless communication at a UE, the code comprising instructions executable by a processor to perform the method of any one of aspects 1 to 14.

[0476] Aspect 113: An apparatus for wireless communication at a base station, comprising a processor and a memory coupled to the processor, and the processor and the memory are configured to perform the method of any one of aspects 15 to 17.

[0477] Aspect 114: An apparatus for wireless communication at a base station, comprising at least one means for performing the method of any one of Aspects 15 to 17.

[0478] Aspect 115: A non-transitory computer-readable medium storing code for wireless communication at a base station, the code comprising instructions executable by a processor to perform the method of any one of aspects 15 to 17.

[0479] Aspect 116: An apparatus for wireless communication at a UE, comprising a processor and a memory coupled to the processor, the processor and the memory configured to perform the method of any one of aspects 18 to 24.

[0480] Aspect 117: An apparatus for wireless communication at a UE, comprising at least one means for performing the method of any one of aspects 18 to 24.

[0481] Aspect 118: A non-transitory computer-readable medium storing code for wireless communication at a UE, the code comprising instructions executable by a processor to perform the method of any one of aspects 18 to 24.

[0482] Aspect 119: An apparatus for wireless communication at a UE, comprising a processor and a memory coupled to the processor, the processor and the memory being configured to perform the method of any one of aspects 25 to 28.

[0483] Aspect 120: An apparatus for wireless communication at a UE, comprising at least one means for performing the method of any one of aspects 25 to 28.

[0484] Aspect 121: A non-transitory computer-readable medium storing code for wireless communication at a UE, the code comprising instructions executable by a processor to perform the method of any one of aspects 25 to 28.

[0485] Aspect 122: An apparatus for wireless communication at a base station, comprising: a processor; a memory coupled to the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform the method of any one of Aspects 29 to 30.

[0486] Aspect 123: An apparatus for wireless communication at a base station, comprising at least one means for performing the method of any one of Aspects 29 to 30.

[0487] Aspect 124: A non-transitory computer-readable medium storing code for wireless communication at a base station, the code comprising instructions executable by a processor to perform the method of any one of aspects 29 to 30.

[0488] Aspect 125: An apparatus for wireless communication, comprising a processor; and a memory coupled to the processor, the processor and the memory configured to perform the method of any one of aspects 31-55.

[0489] Aspect 126: An apparatus for wireless communication, comprising at least one means for performing the method of any of Aspects 31-55.

[0490] Aspect 127: A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by a processor to perform the method of any one of aspects 31-55.

[0491] Aspect 128: An apparatus for wireless communication, comprising a processor; and a memory coupled to the processor, the processor and the memory configured to perform the method of any one of aspects 56-70.

[0492] Aspect 129: An apparatus for wireless communication, comprising at least one means for performing the method of any of Aspects 56-70.

[0493] Aspect 130: A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by a processor to perform the method of any one of aspects 56-70.

[0494] Aspect 131: An apparatus for wireless communication, comprising a processor; and a memory coupled to the processor, the processor and the memory configured to perform the method of any one of aspects 71-81.

[0495] Aspect 132: An apparatus for wireless communication, comprising at least one means for performing the method of any of Aspects 71-81.

[0496] Aspect 133: A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by a processor to perform the method of any one of aspects 71-81.

[0497] Aspect 134: An apparatus for wireless communication, comprising a processor; and a memory coupled to the processor, the processor and the memory configured to perform the method of any one of aspects 82-87.

[0498] Aspect 135: An apparatus for wireless communication, comprising at least one means for performing the method of any of Aspects 82-87.

[0499] Aspect 136: A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by a processor to perform the method of any one of aspects 82-87.

[0500] Aspect 137: An apparatus for wireless communication, comprising a processor; and a memory coupled to the processor, the processor and the memory configured to perform the method of any one of aspects 88-96.

[0501] Aspect 138: An apparatus for wireless communication, comprising at least one means for performing the method of any of Aspects 88-96.

[0502] Aspect 139: A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by a processor to perform the method of any one of aspects 88-96.

[0503] Aspect 140: An apparatus for wireless communication, comprising a processor; and a memory coupled to the processor, the processor and the memory configured to perform the method of any one of aspects 97-102.

[0504] Aspect 141: An apparatus for wireless communication, comprising at least one means for performing the method of any of Aspects 97-102.

[0505] Aspect 142: A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by a processor to perform the method of any one of aspects 97-102.

[0506] Aspect 143: An apparatus for wireless communication, comprising a processor; and a memory coupled to the processor, the processor and the memory configured to perform the method of any one of aspects 103-109.

[0507] Aspect 144: An apparatus for wireless communication, comprising at least one means for performing the method of any of Aspects 103-109.

[0508] Aspect 145: A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by a processor to perform the method of any one of aspects 103-109.

[0509] Although aspects of LTE, LTE-A, LTE-A Pro, or NR systems may be described for example purposes, and LTE, LTE-A, LTE-A Pro, or NR terminology may be used throughout much of the description, the techniques described herein may also be applicable to networks other than LTE, LTE-A, LTE-A Pro, or NR networks. For example, the techniques described may be applicable to various other wireless communication 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, and other systems and radio technologies not explicitly mentioned herein.

[0510] The 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 referred to throughout this description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0511] The various illustrative blocks and components described in conjunction 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. The processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration).

[0512] 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 by a computer-readable medium as one or more instructions or code. Other examples and implementations fall within the scope of this disclosure and the appended claims. For example, due to the nature of software, the functions described herein may be implemented using software executed by a processor, hardware, firmware, hardwiring, or any combination thereof. Features that implement the functions may also be physically located in various locations, including being distributed so that parts of the functions are implemented at different physical locations.

[0513] Computer-readable media include both non-transient computer storage media and communication media, which include any media that facilitates a computer program to be transferred from one place to another. Non-transient storage media can be any available medium that can be accessed by a general or special-purpose computer. As an example and not limitation, non-transient computer-readable media may include RAM, ROM, electrically erasable programmable ROM (EEPROM), flash memory, compact disc (CD) ROM or other optical disc storage, magnetic disk storage or other magnetic storage devices, or any other non-transient medium that can be used to carry or store the desired program code means of an instruction or data structure form and can be accessed by a general or special-purpose computer, or a general or special-purpose processor. Similarly, any connection is also properly referred to as a computer-readable medium. For example, if 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 microwaves, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwaves are included in the definition of computer-readable media. Disk and disc, as used herein, include CDs, laser discs, optical discs, digital versatile discs (DVDs), floppy disks, and Blu-ray discs, 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.

[0514] As used herein (including in the claims), "or" used in a list of items (e.g., a list of items followed by a phrase such as "at least one of" or "one or more of") indicates an inclusive list, so 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). Likewise, as used herein, the phrase "based on" should not be read as referencing a closed set of conditions. For example, an example step described as "based on condition A" could be based on both condition A and condition B without departing from the scope of this disclosure. In other words, as used herein, the phrase "based on" should be read in the same manner as the phrase "based at least in part on."

[0515] In the accompanying drawings, similar components or features may have the same reference number. In addition, components of the same type may be distinguished by following the reference number with a dash and a second reference number that distinguishes between the similar components. If only the first reference number is used in the specification, the description applies to any of the similar components having the same first reference number, regardless of the second reference number or other subsequent reference numbers.

[0516] The description set forth herein in conjunction with the accompanying drawings describes example configurations and does not represent all examples that can be implemented or fall within the scope of the claims. The term "example" as used herein means "serving as an example, instance, or illustration" and does not mean "better than" or "better than other examples." This detailed description includes specific details to provide an understanding of the described techniques. However, these techniques can be practiced without these specific details. In some instances, known structures and devices are shown in block diagram form to avoid obscuring the concepts of the described examples.

[0517] The description herein is provided to enable one of ordinary skill in the art to make or use the present disclosure. Various modifications to the present disclosure will be apparent to those of ordinary skill in the art, and the general principles defined herein may be applied to other variations without departing from the scope of the present disclosure. Thus, the present disclosure is not limited to the examples and designs described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for wireless communication at a user equipment (UE), comprising: transmitting a random access message associated with a random access procedure to a network device, wherein hybrid automatic repeat request (HARQ) feedback is disabled for a first downlink data channel transmission associated with the random access procedure; Initiating a contention resolution window associated with the random access procedure for the first downlink data channel transmission associated with the random access procedure among a plurality of downlink data channel transmissions; receiving the first downlink data channel transmission within the contention resolution window, wherein the first downlink data channel transmission comprises a contention resolution medium access control-control element (MAC-CE); and An uplink alignment timer is activated or deactivated regardless of the HARQ feedback.

2. The method of claim 1, wherein the random access message comprises a random access message 3.

3. The method of claim 1, further comprising: Acknowledgement information regarding the first downlink data channel transmission including the contention resolution MAC-CE is transmitted based at least in part on an indication that the HARQ feedback for the random access procedure is to be enabled.

4. The method of claim 3, further comprising: identifying the indication to enable the HARQ feedback based at least in part on a default configuration for enabling the HARQ feedback; as well as The HARQ feedback is enabled based at least in part on the indication.

5. The method of claim 3, further comprising: A request to enable the HARQ feedback for the first downlink data channel transmission including the contention resolution MAC-CE is transmitted in the random access message.

6. The method of claim 3, further comprising: receiving the indication in the contention resolution MAC-CE; as well as The HARQ feedback is enabled based at least in part on the indication in the contention resolution MAC-CE.

7. The method of claim 3, further comprising: receiving a downlink control information message scheduling the first downlink data channel transmission including the contention resolution MAC-CE, wherein the downlink control information message includes the indication to enable the HARQ feedback for the first downlink data channel transmission including the contention resolution MAC-CE associated with the random access procedure.

8. The method of claim 3, further comprising: determining resources associated with an uplink control channel based at least in part on a second indication in the contention resolution MAC-CE, wherein the second indication comprises a new MAC-CE indicating uplink control channel resources, and wherein transmitting the acknowledgment information comprises: The acknowledgment information is transmitted on the uplink control channel based at least in part on the determined resources.

9. The method of claim 8, wherein a logical channel identifier of the new MAC-CE is the same as or different from that of the contention resolution MAC-CE.

10. The method of claim 3, further comprising: A reception failure of the first downlink data channel transmission including the contention resolution MAC-CE is determined, wherein the HARQ feedback is enabled for the random access procedure and the acknowledgment information includes a negative acknowledgment.

11. The method of claim 3, wherein transmitting the acknowledgment information comprises: The acknowledgment information is transmitted based at least in part on an expiration of the contention resolution window, wherein the HARQ feedback is enabled for the random access procedure and the acknowledgment information comprises a negative acknowledgment.

12. The method of claim 1, further comprising: receiving a radio resource control message including an indication to disable the HARQ feedback for the random access procedure; as well as The HARQ feedback is determined to be disabled based at least in part on the received radio resource control message.

13. The method of claim 1, further comprising: receiving a random access response message associated with the random access procedure, wherein the random access response message includes a timing advance; and The uplink alignment timer is activated or deactivated based at least in part on the timing advance or the disabled HARQ feedback for the random access procedure, or both.

14. The method of claim 1, wherein the network device is a non-terrestrial network device comprising a satellite or a high altitude platform station in a non-terrestrial network.

15. The method of claim 3, further comprising: identifying the indication to enable the HARQ feedback based at least in part on UE context information or a network configuration for enabling the HARQ feedback, or both; as well as The HARQ feedback is enabled based at least in part on the indication.

16. The method of claim 3, further comprising: A radio resource control configuration is received including the indication that the HARQ feedback for the random access procedure is to be enabled.

17. A method for wireless communication at a network device, comprising: receiving a random access message associated with a random access procedure, wherein hybrid automatic repeat request (HARQ) feedback is disabled for a first downlink data channel transmission associated with the random access procedure, and wherein a contention resolution window is associated with the random access procedure for the first downlink data channel transmission associated with the random access procedure among a plurality of downlink data channel transmissions; as well as The first downlink data channel transmission is transmitted within the contention resolution window, wherein the first downlink data channel transmission comprises a contention resolution medium access control-control element (MAC-CE), wherein an uplink alignment timer is configured to be activated or deactivated regardless of the HARQ feedback.

18. The method of claim 17, further comprising: transmitting an indication that the HARQ feedback is to be enabled; as well as Acknowledgement information regarding the first downlink data channel transmission including the contention resolution MAC-CE is received based at least in part on the indication that the HARQ feedback is to be enabled.

19. The method of claim 18, further comprising: The indication in the contention resolution MAC-CE is transmitted.

20. The method of claim 18, wherein transmitting the indication comprises: Downlink control information or radio resource control configuration including the indication that the HARQ feedback for the random access procedure is to be enabled is transmitted.

21. An apparatus for wireless communication at a user equipment (UE), comprising: one or more memories; as well as one or more processors coupled to the one or more memories and configured to cause the UE to: transmitting a random access message associated with a random access procedure to a network device, wherein hybrid automatic repeat request (HARQ) feedback is disabled for a first downlink data channel transmission associated with the random access procedure; Initiating a contention resolution window associated with the random access procedure for the first downlink data channel transmission associated with the random access procedure among a plurality of downlink data channel transmissions; receiving the first downlink data channel transmission within the contention resolution window, wherein the first downlink data channel transmission comprises a contention resolution medium access control-control element (MAC-CE); and An uplink alignment timer is activated or deactivated regardless of the HARQ feedback.

22. The apparatus of claim 21, wherein the random access message comprises a random access message 3.

23. The apparatus of claim 21 , wherein the one or more processors are configured to cause the UE to: Acknowledgement information regarding the first downlink data channel transmission including the contention resolution MAC-CE is transmitted based at least in part on an indication that the HARQ feedback for the random access procedure is to be enabled.

24. The apparatus of claim 23, wherein the one or more processors are configured to cause the UE to: identifying the indication to enable the HARQ feedback based at least in part on a default configuration for enabling the HARQ feedback; and The HARQ feedback is enabled based at least in part on the indication.

25. The apparatus of claim 23, wherein the one or more processors are configured to cause the UE to: identifying the indication to enable the HARQ feedback based at least in part on UE context information or a network configuration for enabling the HARQ feedback, or both; and The HARQ feedback is enabled based at least in part on the indication.

26. The apparatus of claim 23, wherein the one or more processors are configured to cause the UE to: A radio resource control configuration is received including the indication that the HARQ feedback for the random access procedure is to be enabled.

27. The apparatus of claim 23, wherein to receive the indication, the one or more processors are configured to cause the UE to: receive downlink control information or radio resource control configuration including the indication to enable the HARQ feedback for the random access procedure.

28. An apparatus for wireless communication at a network device, comprising: one or more memories; as well as one or more processors coupled to the one or more memories and configured to cause the network device to: receiving a random access message associated with a random access procedure, wherein hybrid automatic repeat request (HARQ) feedback is disabled for a first downlink data channel transmission associated with the random access procedure, and wherein a contention resolution window is associated with the random access procedure for the first downlink data channel transmission associated with the random access procedure among a plurality of downlink data channel transmissions; as well as The first downlink data channel transmission is transmitted within the contention resolution window, wherein the first downlink data channel transmission comprises a contention resolution medium access control-control element (MAC-CE), wherein an uplink alignment timer is configured to be activated or deactivated regardless of the HARQ feedback.

29. The apparatus of claim 28, wherein the one or more processors are configured to cause the network device to: transmitting an indication that the HARQ feedback is to be enabled; and Acknowledgement information regarding the first downlink data channel transmission including the contention resolution MAC-CE is received based at least in part on the indication that the HARQ feedback is to be enabled.

30. The apparatus of claim 29, wherein the one or more processors are configured to cause the network device to: The indication in the contention resolution MAC-CE is transmitted.

31. A non-transitory computer-readable medium storing code for wireless communication at a user equipment (UE), the code comprising instructions executable by one or more processors to cause the UE to: transmitting a random access message associated with a random access procedure to a network device, wherein hybrid automatic repeat request (HARQ) feedback is disabled for a first downlink data channel transmission associated with the random access procedure; Initiating a contention resolution window associated with the random access procedure for the first downlink data channel transmission associated with the random access procedure among a plurality of downlink data channel transmissions; receiving the first downlink data channel transmission within the contention resolution window, wherein the first downlink data channel transmission comprises a contention resolution medium access control-control element (MAC-CE); and An uplink alignment timer is activated or deactivated regardless of the HARQ feedback.

32. The non-transitory computer-readable medium of claim 31, wherein the random access message comprises Random Access Message 3.

33. The non-transitory computer-readable medium of claim 31 , wherein the instructions are further executable by the one or more processors to cause the UE to: Acknowledgement information regarding the first downlink data channel transmission including the contention resolution MAC-CE is transmitted based at least in part on an indication that the HARQ feedback for the random access procedure is to be enabled.

34. A non-transitory computer-readable medium storing code for wireless communication at a network device, the code comprising instructions executable by one or more processors to cause the network device to: receiving a random access message associated with a random access procedure, wherein hybrid automatic repeat request (HARQ) feedback is disabled for a first downlink data channel transmission associated with the random access procedure, and wherein a contention resolution window is associated with the random access procedure for the first downlink data channel transmission associated with the random access procedure among a plurality of downlink data channel transmissions; and The first downlink data channel transmission is transmitted within the contention resolution window, wherein the first downlink data channel transmission comprises a contention resolution medium access control-control element (MAC-CE), wherein an uplink alignment timer is configured to be activated or deactivated regardless of the HARQ feedback.

35. The non-transitory computer-readable medium of claim 34, wherein the instructions are further executable by the one or more processors to cause the network device to: transmitting an indication that the HARQ feedback is to be enabled; and Acknowledgement information regarding the first downlink data channel transmission including the contention resolution MAC-CE is received based at least in part on the indication that the HARQ feedback is to be enabled.

36. The non-transitory computer-readable medium of claim 35, wherein the instructions are further executable by the one or more processors to cause the network device to: The indication in the contention resolution MAC-CE is transmitted.

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