HARQ Process Selection

Abstract

An example embodiment of the present disclosure relates to de-prioritizing retransmissions. A device determines whether there is no user data in a transport block to be retransmitted via a hybrid automatic repeat request process. The device de-prioritizes the selection of a hybrid automatic repeat request process for one or more transmissions in a configuration grant based at least in part on the determination. This solution can avoid or de-prioritize unnecessary retransmissions of transport blocks with no user data.

Description

[Technical field]

[0001] FIELD OF THE DISCLOSURE

[0002] Embodiments of the present disclosure relate generally to the field of telecommunications, and more particularly to devices, methods, apparatus, and computer-readable storage media for Hybrid Automatic Repeat Request (HARQ) process selection. [Background technology]

[0002] In wireless communication, an uplink (UL) transmission without a dynamic UL grant may be referred to as a grant-free (GF) UL transmission or a configured grant (CG) transmission. In a CG transmission, a communication device may be configured to transmit a transport block (TB) using a CG resource without a dynamic UL grant. In the case of 5G new radio in an unlicensed spectrum (NR-U), a communication device may be required to retransmit a TB in a HARQ process to confirm that the TB has been successfully received when it does not receive any feedback from other communication devices. In operation, a terminal device may use multiple HARQ processes for initial transmission or retransmission of different TBs. If a CG is available, the terminal device may determine which HARQ process to select for transmission in the CG. Summary of the Invention

[0003] In general, the exemplary embodiments of the present disclosure provide a solution for selecting a HARQ process for a CG. The embodiments not included in the claims, if any, should be construed as examples useful for understanding various embodiments of the present disclosure.

[0004] In a first aspect, a device is provided comprising at least one processor and at least one memory including computer program code that, together with the at least one processor, causes the device to determine whether user data is absent in a transport block to be retransmitted via a hybrid automatic repeat request process and, based at least in part on the determination, de-prioritize the selection of a hybrid automatic repeat request process for one or more transmissions in a configuration grant.

[0005] In a second aspect, a method is provided that includes determining whether user data is absent in a transport block to be retransmitted via a hybrid automatic repeat request process, and de-prioritizing a selection of the hybrid automatic repeat request process for one or more transmissions in a configuration grant based at least in part on the determination.

[0006] In a third aspect, an apparatus is provided that includes means for determining whether user data is absent in a transport block to be retransmitted via a hybrid automatic repeat request process, and means for de-prioritizing selection of the hybrid automatic repeat request process for one or more transmissions in a configuration grant based at least in part on the determination.

[0007] In a fourth aspect, there is provided a computer readable medium comprising program instructions for causing an apparatus to perform at least a method according to the first aspect.

[0008] It should be understood that this Summary section is not intended to identify key or essential features of the embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will become readily apparent through the following description.

[0009] Some example embodiments will now be described with reference to the accompanying drawings. [Brief description of the drawings]

[0010] [Figure 1] 1 illustrates an exemplary communications environment in which exemplary embodiments of the present disclosure may be practiced. [Diagram 2] 1 shows a flowchart of a method implemented in a device according to some exemplary embodiments of the present disclosure. [Diagram 3] FIG. 1 shows a simplified block diagram of a device suitable for practicing exemplary embodiments of the present disclosure. [Figure 4] 1 illustrates a block diagram of an exemplary computer-readable medium in accordance with some exemplary embodiments of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Throughout the drawings, the same or similar reference numbers represent the same or similar elements.

[0012] The principles of the present disclosure will now be described with reference to some exemplary embodiments. It should be understood that these embodiments are merely described for illustrative purposes, to help those skilled in the art understand and practice the present disclosure, but do not imply any limitations on the scope of the present disclosure. The embodiments described herein can be implemented in various ways other than those described below.

[0013] In the following description and claims, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs, unless otherwise defined.

[0014] References in this disclosure to "one embodiment," "embodiment," "exemplary embodiment," and the like indicate that the described embodiment may include a particular feature, structure, or characteristic, but not all embodiments need to include that particular feature, structure, or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment. Furthermore, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is believed to be within the knowledge of one of ordinary skill in the art to affect such feature, structure, or characteristic with respect to other embodiments, whether or not explicitly described.

[0015] In this specification, terms such as "first" and "second" may be used to describe various elements, but it is understood that these elements should not be limited by these terms. These terms are used only to distinguish one element from another. For example, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element, without departing from the scope of the example embodiments. As used herein, the term "and / or" includes any and all combinations of one or more of the listed terms.

[0016] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms unless the context clearly indicates otherwise. When the terms "comprises," "comprising," "has," "having," "includes," and / or "including" are used herein, it will be understood that these terms specify the presence of stated features, elements, and / or components, etc., but do not exclude the presence or addition of one or more other features, elements, components, and / or combinations thereof.

[0017] As used herein, the term "circuitry" may mean one or more or all of the following: (a) hardware-only circuit implementations (e.g., implementations in analog and / or digital circuitry only); (b) A combination of hardware circuitry and software, such as (where applicable) (i) A combination of analog and / or digital hardware circuitry(s) and software / firmware; and (ii) hardware processor(s) (including digital signal processor(s)) with software, software, and any portion of memory(s) that cooperate to cause a device, such as a mobile phone or a server, to perform various functions; (c) Hardware circuit(s) and / or processor(s), such as a microprocessor(s) or part of a microprocessor(s), that requires software (e.g., firmware) to operate, but the software may not be present when not necessary for operation.

[0018] This definition of "circuitry" applies to all uses of the term in this application, including any claims. As a further example, the term circuitry, as used herein, encompasses an embodiment of merely a hardware circuit or processor (or processors), or a portion of a hardware circuit or processor, as well as its (or their) associated software and / or firmware. The term circuitry also covers, for example, a baseband or processor integrated circuit of a mobile device, or similar integrated circuit of a server, cellular network device, or other computing or network device, if applicable to certain claim elements.

[0019] As used herein, the term "communication network" refers to a network conforming to any suitable communication standard, such as New Radio (NR), Long Term Evolution (LTE), LTE Advanced (LTE-A), Wideband Code Division Multiple Access (WCDMA), High Speed ​​Packet Access (HSPA), Narrowband Internet of Things (NB-IoT), etc. Furthermore, communication between terminal devices and network devices in the communication network may be performed according to any suitable generation of communication protocols, including, but not limited to, first generation (1G), second generation (2G), 2.5G, 2.75G, third generation (3G), fourth generation (4G), 4.5G, fifth generation (5G) communication protocols, and / or any other protocols now known or hereafter developed. The embodiments of the present disclosure may be applied to various communication systems. Given the rapid development in communication, of course, there will also be future communication technologies and systems in which the present disclosure may be embodied. The scope of the present disclosure should not be considered as being limited to only the aforementioned systems.

[0020] As used herein, the term "network device" refers to a node in a communication network through which a terminal device accesses the network and receives services therefrom. Depending on the terminology and technology applied, a network device may refer to a base station (BS) or access point (AP), such as a Node B (NodeB or NB), evolved Node B (eNodeB or eNB), NR NB (also called gNB), remote radio unit (RRU), radio header (RH), remote radio head (RRH), relay, integrated access and backhaul (IAB) node, low power nodes such as femto and pico, satellite network devices, low earth orbit (LEO) and geostationary earth orbit (GEO) satellites, non-terrestrial network (NTN) or non-terrestrial network devices such as aircraft network devices, etc. In some exemplary embodiments, a Radio Access Network (RAN) split architecture comprises an aggregation unit (CU) and a distribution unit (DU) in an IAB donor node. An IAB node comprises a mobile terminal (IAB-MT) portion that behaves like a UE towards a parent node, and the DU portion of the IAB node behaves like a base station towards the next-hop IAB node.

[0021] The term "terminal device" refers to any end device that may be capable of wireless communication. By way of example and not limitation, a terminal device may also be referred to as a communication device, user equipment (UE), subscriber station (SS), mobile subscriber station, mobile station (MS), or access terminal (AT). Terminal devices may include, but are not limited to, mobile phones, cell phones, smartphones, voice over IP (VoIP) phones, wireless local loop phones, tablets, wearable terminal devices, personal digital assistants (PDAs), portable computers, desktop computers, image capture terminal devices such as digital cameras, gaming terminal devices, music storage and playback appliances, in-vehicle wireless terminal devices, wireless endpoints, mobile stations, laptop embedded equipment (LEE), laptop mounted equipment (LME), USB dongles, smart devices, wireless customer premises equipment (CPE), Internet of Things (loT) devices, watches or other wearables, head mounted displays (HMD), vehicles, drones, medical devices and applications (e.g., remote surgery), industrial devices and applications (e.g., robots and / or other wireless devices operating in the context of industrial processing and / or automated processing chains), consumer electronics devices, devices operating on commercial and / or industrial wireless networks, and the like. Terminal devices may also correspond to the mobile termination (MT) portion of an IAB node (e.g., a relay node). In the following description, the terms "terminal device", "communication device", "terminal", "user equipment" and "UE" may be used interchangeably.

[0022] As used herein, the terms "resource", "transmission resource", "resource block", "physical resource block" (PRB), "uplink resource", or "downlink resource" may refer to any resource for performing communication, e.g., communication between a terminal device and a network device, such as a time domain resource, a frequency domain resource, a spatial domain resource, a code domain resource, or other resource that enables communication. In the following, both frequency domain and time domain resources are used as examples of transmission resources to explain some exemplary embodiments of the present disclosure. It should be noted that the exemplary embodiments of the present disclosure are equally applicable to other resources in other domains.

[0023] As used herein, the term "CG" may also be referred to as "CG resources" and may refer to resource(s) configured on a device(s) for transmission without a dynamic UL grant. The terms "CG resources" and "CG" are used interchangeably herein.

[0024] As mentioned above, a communication device (e.g., a terminal device) may be configured to use one or more CGs to transmit one or more TBs without a dynamic UL grant. By using a CG, a communication device may be able to reduce signaling overhead compared to a grant-based UL transmission. Furthermore, a communication device configured for a CG may skip UL transmission, for example, when there is no user data to be transmitted to the communication device. However, in some cases, it is also specified that a communication device cannot skip UL transmission in a CG. For example, when a physical uplink shared channel (CG-PUSCH) of a CG overlaps with a physical uplink control channel (PUCCH), the communication device is specified to multiplex uplink control information (UCI) from the PUCCH with the CG-PUSCH. In this case, even though there is no user data, the communication device may still generate a TB without user data, which may be multiplexed with or include UCI for transmission in this CG. The term "UCI-only TB" may refer to a TB that is multiplexed with or generated to include control information (e.g., UCI) rather than including user data.

[0025] Furthermore, it is specified that retransmissions shall be prioritized over initial transmissions. However, it has been recently proposed that such rules should be reconsidered, since in some cases higher priority traffic may be carried in the initial transmission. In NR-U, if a communication device transmits a TB in a CG using a HARQ process and does not receive any feedback from other communication devices, the communication device may autonomously retransmit the TB in a subsequent CG. This means that when processing a subsequent CG, the communication device may prioritize the retransmission of the TB over other initial transmissions. In other words, the communication device may select this HARQ process for transmission when processing a subsequent CG. Thus, if the communication device transmits the above CG-PUSCH using a HARQ process and does not receive any feedback for the HARQ process, the communication device may autonomously retransmit the UCI dedicated TB.

[0026] However, it may be meaningless and unnecessary to always prioritize HARQ processes for retransmission of TBs without user data over initial transmission. For example, when dealing with ultra-reliable low-latency communication systems (URLLC), the initial transmission may carry some high-priority traffic. To address this issue, currently in RAN2#113e, logical channel (LCH)-based prioritization is configured, and it is agreed that initial transmission and retransmission may be prioritized based on the priority of the multiplexed LCH(s) or the priority of the LCH(s) to be multiplexed. However, this solution does not apply to the case involving UCI-only TBs. As mentioned above, UCI-only TBs cannot contain user data. Therefore, UCI-only TBs may not be assigned LCH-based priority. Thus, LCH-based prioritization cannot yet be used to address the issue of retransmission(s) of UCI-only TBs in HARQ process selection.

[0027] According to the above discussion, it is desirable to design an improved mechanism for selecting a HARQ process.

[0028] According to some example embodiments of the present disclosure, an improved solution for selecting HARQ processes in a CG is provided, in which a device determines whether there is no user data in a TB for retransmission through a HARQ process. According to at least the determination, the device deprioritizes the selection of HARQ processes for one or more transmissions in the CG. This solution can avoid or deprioritize unnecessary retransmissions of TBs that have no user data. Thus, other HARQ processes for retransmissions and / or initial transmissions of user traffic may be more likely to be transmitted as soon as possible.

[0029] Exemplary embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.

[0030] 1 illustrates an exemplary communication environment 100 in which exemplary embodiments of the present disclosure may be implemented. In the communication environment 100, multiple communication devices, including a device 110 and a device 120, may communicate with each other.

[0031] 1, device 110 is shown as a terminal device and device 120 is shown as a network device that serves the terminal device. The serving area of ​​device 120 may be referred to as cell .

[0032] It should be understood that the number of devices and their connections shown in FIG. 1 are for illustrative purposes only and do not imply any limitations. The environment 100 may include any suitable number of devices compatible with implementing embodiments of the present disclosure. Although not shown, it should be understood that one or more additional devices may be located within the cell 102 and one or more additional cells may be deployed within the environment 100. It should be noted that the device 120 is shown as a network device, but may be a device other than a network device. For example, the device 120 may be another terminal device in sidelink communication with the device 110. The device 110 is shown as a terminal device, but may be a device other than a terminal device.

[0033] In some demonstrative embodiments, when device 110 is a terminal device and device 120 is a network device, the link from device 120 to device 110 is called a downlink (DL) and the link from device 110 to device 120 is called an uplink (UL). In the DL, device 120 is a transmit (TX) device (or transmitter) and device 110 is a receive (RX) device (or receiver). In the UL, device 110 is a TX device (or transmitter) and device 120 is a RX device (or receiver).

[0034] Communications in the communication environment 100 may be performed according to any suitable communications protocol(s), including, but not limited to, cellular communications protocols such as first generation (1G), second generation (2G), third generation (3G), fourth generation (4G), and fifth generation (5G), wireless local network communications protocols such as Institute for Electrical and Electronics Engineers (IEEE) 802.11 and the like, and / or any other protocols now known or to be developed in the future. Further, the communications may utilize any suitable wireless communication technology, including, but not limited to, code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), frequency division duplex (FDD), time division duplex (TDD), multiple-input multiple-output (MIMO), orthogonal frequency division multiplexing (OFDM), discrete Fourier transform spread OFDM (DFT-s-OFDM), and / or any other technology now known or to be developed in the future.

[0035] In operation, device 110 may transmit user data and / or control information to device 120 using the allocated and / or configured resources. The control information may include UCI. In some demonstrative embodiments, the control information may include HARQ feedback information such as HARQ-acknowledgement (HARQ-ACK), channel state information (CSI), scheduling request (SR), and configuration grant uplink control information (CG-UCI).

[0036] 2, which illustrates a flowchart of an example method 200 implemented on device 110, in accordance with some example embodiments of the present disclosure. For purposes of discussion, method 200 is described from the perspective of device 110 with respect to FIG. 1. In some example embodiments, device 110 may be a terminal device.

[0037] At block 210, the device 110 determines whether there is user data in the TB to be retransmitted through the HARQ process.

[0038] According to an exemplary embodiment of the present disclosure, in any HARQ process, the device 110 determines whether a TB to be retransmitted through this HARQ process includes user data. In some exemplary embodiments, the device 110 may further determine whether a TB is generated to be multiplexed with control information or to include only control information. A TB that does not include user data may be referred to herein as a UCI-only TB, which is generated only to be multiplexed with control information or to include control information. In some exemplary embodiments, the media access control (MAC) of the device 110 may perform HARQ process selection and, as a result, determine whether a TB does not include user data, but rather a TB is generated only to be multiplexed with control information or to include control information at the physical (PHY) layer of the device 110.

[0039] A TB that does not contain user data may be generated for various reasons and may almost certainly be transmitted at least once through the HARQ process. In some exemplary embodiments, such a TB may be generated in response to an overlap between resources for control information (e.g., UCI) and a CG prior to the currently processed CG. The resources for control information may include resources for PUCCH. According to some specifications, if the CG-PUSCH overlaps with the PUCCH, the device 110 is specified to multiplex UCI from the PUCCH with the CG-PUSCH. The overlap may be a full overlap between one or more CGs and resources for control information, or a partial overlap. In this case, the device 110 may generate and convey a TB if there was no user data available for the previous CG. For example, the MAC layer of the device 110 may generate a MAC protocol data unit (PDU) for the CG-PUSCH and convey the MAC PDU to the PHY layer. It should be noted that the MAC PDU may be equivalent to a TB. The PHY layer of the device 110 can multiplex or include control information from the PUCCH into the TB. As an example, the UCI and the MAC PDU are coded separately. In such a case, due to the overlap between the CG-PUSCH and the PUCCH, a TB is generated for the sole purpose of multiplexing the control information.

[0040] In some exemplary embodiments, as an alternative or additional condition, a UCI dedicated TB may be generated when LCH-based prioritization is not configured and there is a single PHY priority for UL transmission. Additionally or alternatively, a UCI dedicated TB may be generated when PUSCH repetition is not applied and there is no dynamic grant (DG) PUSCH that overlaps with one or more CG-PUSCHs. Additionally or alternatively, if there is a non-periodic CSI requested to be transmitted via a PUSCH that overlaps with a CG-PUSCH, the device 110 may generate and convey a TB (e.g., a UCI dedicated TB) that does not include user data to be multiplexed with control information for transmission in the CG, or a TB (e.g., a UCI dedicated TB) that does not include user data that includes this control information. Additionally or alternatively, if there is a periodic or semi-periodic CSI to be transmitted via a PUCCH that overlaps with a CG-PUSCH, the device 110 may generate and convey a TB (e.g., a UCI dedicated TB) that does not include user data to be multiplexed with control information for transmission in the CG, or a TB (e.g., a UCI dedicated TB) that does not include user data that includes this control information. Additionally or alternatively, the device 110 may determine whether a CG TB should be generated and conveyed according to the presence / value of RRC parameters such as cg-UCI-Multiplexing or cg-RetransmissionTimer. In some example embodiments, the device 110 may determine not to generate a TB in the absence of data if there is HARQ-ACK information and / or CSI that overlaps with a CG-PUSCH transmission and cg-UCI-Multiplexing or cg-retransmissionTimer is not configured.

[0041] If a TB without user data is generated and transmitted in a previous CG through the HARQ process, the retransmission of this TB may be carefully determined by the device 110. Therefore, when processing the current CG, the device 110 may check that there is no user data in the TB.

[0042] In some embodiments, the device 110 may check whether the TB includes one or more segments that store user data to determine whether user data is present in the TB. If no user data is found in the TB, for example if the TB does not include a MAC control element (CE), a common control channel (CCCH) SDU, a dedicated control channel (DCCH), and / or a service data unit (SDU) of any logical channel (LCH), the device 110 may determine that user data is not present in the TB.

[0043] Additionally or alternatively, the device 110 may determine that there is no user data in the TB by determining why this TB was generated and buffered for the HARQ process. In some exemplary embodiments, the device 110 may determine whether the TB is multiplexed with control information or is generated only to contain control information and, as a result, does not contain user data. For example, the device 110 may check whether the TB does not contain MAC CEs, except for a padding buffer status report (BSR). In some examples, the device 110 may determine that the TB is multiplexed with control information or is generated only to contain control information, such as a hybrid automatic repeat request process acknowledgement (HARQ-ACK), channel state information (CSI), a scheduling request (SR), and / or configuration grant uplink control information (CG-UCI).

[0044] In some exemplary embodiments, the device 110 may determine whether the TB is generated in response to an overlap between a resource for control information (e.g., a PUCCH resource) and a CG earlier than the CG. As described above, the UCI-only TB may be generated in response to an overlap between the CS-PUSCH and the PUCCH in the time domain. Thus, by checking the generation history of the TB, the device 110 may be able to determine whether the TB is generated in response to an overlap between a resource for control information (e.g., a PUCCH resource) and a previous CG, and thus, determine whether user data is included in the TB.

[0045] In some exemplary embodiments, the device 110 may determine whether a CG is available for one or more transmissions of TBs. In some exemplary embodiments, the CG may be configured for an unlicensed band. For example, the CG may be configured for 5G NR-U. In some exemplary embodiments, the device 110 may be configured for one or more CGs, and each CG may be associated with one or more resources for use by the device 110. The device 110 may determine that a CG is available based on the configuration of the CG. The CG may include resources for transmission, such as resources for a CG-PUSCH. If the CG is determined to be available, the device 110 may decide to perform one or more transmissions in the CG, provided that there are one or more pending HARQ processes with one or more TBs to be transmitted. The device 110 may determine which HARQ process may be selected, and may transmit the TBs associated with the selected HARQ process in the current CG.

[0046] When performing a transmission made on a CG, in some cases, the HARQ process associated with a TB to be retransmitted may have a higher priority than other HARQ processes associated with an initial transmission. In some example embodiments, the device 110 may determine whether there is a TB already stored in any HARQ process for retransmission before determining whether there is no user data in the TB. The device 110 may first check whether there is a TB to be retransmitted. If there is no TB stored in any HARQ process for retransmission, the device 110 may select a HARQ process for the initial transmission. If there is a TB stored in the HARQ process for retransmission, the device 110 may determine whether there is no user data in that TB.

[0047] 2, at block 220, the device 110 de-prioritizes the selection of a HARQ process associated with the TB for one or more transmissions in the CG based at least in part on the determination of whether user data is present in the TB. In some example embodiments, if it is determined that the TB does not contain user data (e.g., the TB is a UCI-only TB), de-prioritizing the selection of the corresponding HARQ process may allow other HARQ processes with TBs of useful user data or other meaningful information to be retransmitted in the current CG.

[0048] In some exemplary embodiments, in addition to determining whether there is user data in the TB to be retransmitted through the HARQ process, the device 110 may further determine whether the TB is allowed to be transmitted in a CG or whether the HARQ process is allowed to be used in the CG based on one or more characteristics of the TB and / or based on a configuration associated with the CG. In some examples, the device 110 may determine whether the TB is allowed to be transmitted in a CG based on the size of the TB. The device 110 may determine that the TB is allowed to be transmitted in a CG if the CG has sufficient resources to carry the TB. In some examples, the device 110 may determine that the TB is allowed to be transmitted in a CG based on whether the HARQ process of the TB is allowed to be used in the CG according to the configuration. It will be appreciated that the permission of the TB in a CG may be determined based on other characteristics of the TB. In some other examples, the currently processed CG may be configured for a particular type of transmission, and therefore the current TB is not allowed to be transmitted in this CG.

[0049] In some exemplary embodiments, in addition to there being no user data in the TB, the HARQ process associated with this TB may not be selected for transmission(s) if the TB or HARQ process is not permitted to be transmitted in the CG. In some exemplary embodiments, if the device 110 determines that the TB is permitted to be transmitted in the CG, the device 110 may continue to determine if the TB does not contain user data. If the device 110 instead determines that the TB is prohibited from being transmitted in the CG, the device 110 may reselect another HARQ process for transmission rather than continuing processing the HARQ process for this TB.

[0050] In some example embodiments, the device 110 may deprioritize the selection of a HARQ process for a TB without user data by assigning it a lower priority than one or more other HARQ processes for retransmission and / or a lower priority than one or more HARQ processes for initial transmission. In one example, if a TB is generated only for control information multiplexing, the corresponding HARQ process may be assigned the lowest priority among all HARQ processes having TBs to be transmitted and / or retransmitted. Thus, the device 110 may prevent performing unnecessary retransmissions of a UCI-only TB when there are still other pending HARQ processes with TBs storing user data or other HARQ processes for initial transmission.

[0051] In some exemplary embodiments, the device 110 may lower the priority of the selection of the HARQ process based on the LCH-based prioritization. As described above, according to the conventional solution, the LCH-based priority may not be set for the UCI dedicated TB due to lack of user data. In some exemplary embodiments of the present disclosure, the device 110 may directly assign the lowest priority to the TB (e.g., the UCI dedicated TB). For example, when the LCH-based prioritization is set, the TBs including user data are assigned their respective priorities based on their respective LCHs. Meanwhile, the device 110 may directly assign the lowest priority to the TB without user data. In some examples, the device 110 may assign the lowest priority to the TB after the TB is determined to be a UCI dedicated TB without user data. Alternatively, the device 110 may assign the lowest priority to the TB without user data when the TB is generated.

[0052] In some example embodiments, the device 110 may perform further HARQ process selection based on the deprioritization of the HARQ process selection. The device 110 may select a HARQ process from a plurality of HARQ processes including a low priority HARQ process or a plurality of HARQ processes excluding a low priority HARQ process to perform a transmission in a CG. In addition to the HARQ process with a TB without user data, the device 110 may have one or more other HARQ processes with TBs for retransmissions and / or initial transmissions. The device 110 may select a HARQ process for transmission in a currently available CG.

[0053] In an example embodiment, the device 110 may select a HARQ process based on the respective priorities of the HARQ processes, where a priority of an HARQ process with TBs without user data may be lowered so that this HARQ process has a lower chance of being selected compared to one or more other HARQ processes for retransmissions and / or one or more HARQ processes for initial transmissions.

[0054] Alternatively, the HARQ process with TBs without user data may be excluded from the selectable HARQ processes. That is, the device 110 may lower the selection priority of the HARQ process with TBs without user data, thereby excluding the HARQ process from selection for transmission in the current CG. Thus, the device 110 may remove the HARQ process from consideration when making HARQ process selection for the current CG. The device 110 may select a HARQ process from other HARQ processes for retransmissions and / or initial transmissions in the CG.

[0055] In some exemplary embodiments, an HARQ process may be given a lower priority but may have a chance to be selected for transmission in the current or subsequent CG if there are no other HARQ processes with available data or if the current CG is configured with sufficient resources for the transmission.

[0056] Lowering the priority or excluding the HARQ process can reduce the probability of retransmitting a TB without user data, thereby increasing the probability of early transmission of the HARQ process for the initial transmission or the HARQ process whose stored TB contains user data. In general, retransmission of a TB without user data may be pointless in many cases. For example, since the TB is generated only to be multiplexed with or to contain control information for transmission, the multiplexed control information may already be out of date at the time of autonomous retransmission. For example, the HARQ-ACK in the control information may no longer be needed because the packet delay budget (PDB) will be exhausted anyway. As another example, the CSI in the control information may be out of date due to the mobility of the device 110. As yet another example, the SR in the control information may no longer be needed because the associated buffer status report (BSR) has already been transmitted. In such a case, prioritizing the retransmission of the TB over the initial transmission may be a waste of time and resources. The priority reduction mechanism proposed herein may avoid such problems, thereby enabling timely transmission of user data and / or other useful control information in the CG.

[0057] In some embodiments, if it is determined that the TB to be retransmitted contains user data, the device 110 may select a corresponding HARQ process to perform the transmission of the TB in the CG. In this case, if it is determined that the TB is not a UCI-only TB, the priority of the selection of the corresponding HARQ process may not be lowered, especially if a retransmission of the TB in this HARQ process is to be performed. Thus, the corresponding HARQ process may still have a higher priority than the initial transmission, and the device 110 may select the corresponding HARQ process when processing the CG to transmit the TB again.

[0058] In some exemplary embodiments, if the device 110 determines that a TB does not contain user data or if the selection of the corresponding HARQ process is deprioritized, the device 110 may flush the TB from the buffer associated with the HARQ process. As described above, if a TB does not contain user data, e.g., if the TB is determined as a UCI-only TB, the selection of the HARQ process is deprioritized. In this case, flushing the TB from the buffer associated with the HARQ process can improve the efficiency of buffer usage. In some exemplary embodiments, a TB without user data may be flushed after the first initial transmission and / or before HARQ process selection for the next CG. In some exemplary embodiments, a TB without user data may be flushed during HARQ process selection for the next CG.

[0059] In some exemplary embodiments, in addition to flushing the TB, the device 110 may further stop at least one timer for the HARQ process. In an exemplary embodiment, the at least one timer may include a CG timer. The CG timer may be started upon a previous transmission of the TB in the HARQ process. More specifically, the CG timer may be started when the TB is first transmitted. When the CG timer is running, the corresponding HARQ process is prevented from being reused for transmitting other TBs. By flushing the TB from the buffer and stopping the CG timer, the device 110 may release the corresponding HARQ process for transmitting other TBs.

[0060] In another exemplary embodiment, the device 110 may stop a CG retransmission (CGRT) timer for the HARQ process. The CGRT timer is started when the TB is transmitted, and the TB may be retransmitted if the device 110 does not receive downlink feedback information (DFI) for the transmission of the TB before the CGRT timer expires. In this exemplary embodiment of the present disclosure, if it is determined that the TB does not contain user data, the device 110 may directly flush the TB from the buffer and stop the CGRT timer. Thus, the device 110 may not need to determine whether a DFI is received before the CGRT timer expires. Furthermore, the device 110 may not need to perform further retransmission of the TB even if a DFI is not received before the CGRT expires. The HARQ process may be released and used for the transmission of other TBs. Thus, the utilization efficiency of the HARQ process may be improved.

[0061] Alternatively, the device 110 may determine whether a CGRT timer for a HARQ process of a TB that does not contain user data expires. When the CGRT timer expires, the device 110 may flush the TB from a buffer associated with the HARQ process. In some cases, even if a TB is determined to not contain user data and the selection of the HARQ process is deprioritized, it may still be possible for the device 110 to select a HARQ process and transmit the TB in a subsequent CG if the HARQ process is pending. In this exemplary embodiment, by flushing the TB from the buffer upon expiration of the CGRT timer, the device 110 may not need to select the HARQ process to transmit the TB in a subsequent CG.

[0062] In some demonstrative embodiments, a second apparatus (e.g., device 110) capable of performing any of methods 200 may comprise means for performing each operation of method 200. The means may be implemented in any suitable manner. For example, the means may be implemented in a circuit and / or a software module. The apparatus may be implemented as or included in device 110.

[0063] In some example embodiments, the apparatus comprises means for determining whether there is no user data in the TB to be retransmitted through a HARQ process, and means for de-prioritizing selection of a HARQ process for one or more transmissions in the CG based at least in part on the determination.

[0064] In some example embodiments, the absence of user data in a transport block is determined by at least one of the following: the TB is multiplexed with control information or is generated only to contain control information, and the TB is generated in response to an overlap between resources for control information and a CG earlier than the CG.

[0065] In some exemplary embodiments, the apparatus further comprises means for flushing TBs from a buffer associated with the HARQ process in response to determining that the selection of the HARQ process is deprioritized, and means for stopping at least one timer for the HARQ process in response to determining that the selection of the HARQ process is deprioritized. In some exemplary embodiments, the at least one timer comprises at least one of a CG timer and a CG retransmission timer that was started with a previous transmission of the TB in the HARQ process.

[0066] In some example embodiments, the apparatus further comprises: means for determining whether a CG retransmission timer for the HARQ process has expired in response to a determination that selection of the HARQ process is deprioritized, where the configured grant retransmission timer is started with a previous transmission of a TB in the HARQ process; and means for flushing the TB from a buffer associated with the HARQ process in response to a determination that the configured grant retransmission timer has expired.

[0067] In some exemplary embodiments, the apparatus further comprises means for determining whether the TB is authorized to transmit in the CG. In some exemplary embodiments, the means for determining whether user data is not present at the TB comprises means for determining whether user data is not present at the TB in response to determining that the TB is authorized to transmit in the CG.

[0068] In some exemplary embodiments, the apparatus further comprises means for selecting a hybrid automatic repeat request process for performing a retransmission of the transport block in the configured grant if at least a portion of the user data is included in the transport block.

[0069] In some demonstrative embodiments, the configuration grant is configured in an unlicensed band.

[0070] In some exemplary embodiments, the apparatus comprises a terminal device.

[0071] In some exemplary embodiments, the control information comprises at least one of a Hybrid Automatic Repeat Request Process-Acknowledgement (HARQ-ACK), a Channel State Information (CSI), a Scheduling Request (SR), and a Configuration Grant Uplink Control Information (CG-UCI).

[0072] In some exemplary embodiments, the apparatus further comprises means for performing method 200 or other operations of some exemplary embodiments of device 110. In some exemplary embodiments, the means comprises at least one processor and at least one memory including computer program code, the at least one memory and the computer program code configured, together with the at least one processor, to cause execution of the apparatus.

[0073] 3 illustrates a simplified block diagram of a device 300 suitable for implementing an exemplary embodiment of the present disclosure. The device 300 may be provided to implement a communications device such as, for example, the device 110 or the device 120 illustrated in FIG. 1. As illustrated, the device 300 includes one or more processors 310, one or more memories 320 coupled to the processor 310, and one or more communications modules 340 coupled to the processor 310.

[0074] The communication module 340 is for bidirectional communication. The communication module 340 has one or more communication interfaces to facilitate communication with one or more other modules or devices. The communication interfaces may represent any interface necessary for communication with other network elements. In some exemplary embodiments, the communication module 340 may include at least one antenna.

[0075] The processor 310 may be of any type suitable for a local technology network, including, by way of non-limiting examples, one or more of a general purpose computer, a special purpose computer, a microprocessor, a digital signal processor (DSP), and a processor based on a multi-core processor architecture. The device 300 may have multiple processors, such as application specific integrated circuit chips that are slaved in time to a clock that synchronizes the main processor.

[0076] The memory 320 may include one or more non-volatile memories and one or more volatile memories. Examples of non-volatile memories include, but are not limited to, read only memory (ROM) 324, electrically programmable read only memory (EPROM), flash memory, hard disks, compact disks (CDs), digital video disks (DVDs), optical disks, laser disks, and other magnetic and / or optical storage devices. Examples of volatile memories include, but are not limited to, random access memory (RAM) 322 and other volatile memories that do not persist while power is off.

[0077] The computer program 330 includes computer executable instructions that are executed by the associated processor 310. The program 330 may be stored in a memory, for example in the ROM 324. The processor 310 may load the program 330 into the RAM 322 to perform any suitable operation and processing.

[0078] An exemplary embodiment of the present disclosure may be implemented by a program 330 such that the device 300 can execute any process of the present disclosure described with reference to Fig. 2. An exemplary embodiment of the present disclosure may also be implemented by hardware or a combination of software and hardware.

[0079] In some exemplary embodiments, the program 330 may be tangibly included in a computer-readable medium that may be included in the device 300 (such as the memory 320) or in other storage accessible by the device 300. The device 300 may load the program 330 from the computer-readable medium into the RAM 322 for execution. The computer-readable medium may include any type of tangible non-volatile storage, such as a ROM, an EPROM, a flash memory, a hard disk, a CD, a DVD, etc. FIG. 4 illustrates an example of a computer-readable medium 400, which may be in the form of a CD, a DVD, or other optical storage disk. The computer-readable medium has the program 330 stored thereon.

[0080] In general, various embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic, or any combination thereof. Certain aspects may be implemented in hardware, while other aspects may be implemented in firmware or software that may be executed by a controller, microprocessor, or other computing device. Although various aspects of the embodiments of the present disclosure have been illustrated and described as block diagrams, flow charts, or using some other graphical representations, it should be understood that the blocks, apparatus, systems, techniques, or methods described herein may be implemented, by way of non-limiting examples, in hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controllers or other computing devices, or any combination thereof.

[0081] The present disclosure also provides at least one computer program product tangibly stored in a non-transitory computer-readable storage medium. The computer program product includes computer-executable instructions, e.g., included in program modules, that execute on a target physical or virtual processor device to perform the method described above with reference to FIG. 2. Typically, program modules include routines, programs, libraries, objects, classes, components, or data structures that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split among program modules as desired in various embodiments. The machine-executable instructions of the program modules may be executed in a local device or in a distributed device. In a distributed device, the program modules may be located in both local and remote storage media.

[0082] Program codes for carrying out the methods of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general purpose computer, a special purpose computer, or other programmable data processing apparatus such that, when executed by the processor or controller, the program codes cause the functions / operations specified in the flowcharts and / or block diagrams to be performed. The program codes may be executed entirely on the machine, partially on the machine, as a stand-alone software package, partially on the machine and partially on a remote machine, or entirely on a remote machine or server.

[0083] In the context of the present disclosure, computer program code or associated data may be carried by any suitable carrier to enable a device, apparatus, or processor to perform the various processes and operations described above. Examples of carriers include signals, computer readable media, etc.

[0084] The computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. The computer-readable medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the above. More specific examples of the computer-readable storage medium include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0085] Furthermore, although operations are shown in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown, or sequentially, or that all of the operations shown be performed in order to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Similarly, although details of several specific implementations are included in the above discussion, these should not be construed as limitations on the scope of the disclosure, but rather as descriptions of features that may be specific to certain embodiments. Certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable subcombination.

[0086] Although the present disclosure has been described in language specific to structural features and / or methodological acts, it is to be understood that the present disclosure, as defined by the appended claims, is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms for implementing the claims.

Claims

1. A device At least one processor; at least one memory containing computer program code; Equipped with The at least one memory and the computer program code, together with the at least one processor, cause the device to: determining through a hybrid automatic repeat request process that no user data is present within the transport block for retransmission; in response to determining that the user data is not present within the transport block, decreasing a priority of a selection of the hybrid automatic repeat request process for the retransmission in a configuration grant; A device that causes

2. The absence of user data in the transport block is determined as follows: the transport block is generated only to contain control information; and the transport block is generated in response to an overlap between resources for the control information and a configuration grant that precedes the configuration grant; The device of claim 1 , wherein the at least one of:

3. The at least one memory and the computer program code, together with the at least one processor, in the device further include: in response to determining that selection of the hybrid automatic repeat request process is deprioritized, Flushing the transport block from a buffer associated with the hybrid automatic repeat request process; and / or stopping at least one timer for the hybrid automatic repeat request process, the at least one timer including at least one of a configured grant timer and a configured grant retransmission timer started in a previous transmission of the transport block in the hybrid automatic repeat request process. The device according to claim 1 or 2,

4. The at least one memory and the computer program code, together with the at least one processor, in the device further include: in response to determining that selection of the hybrid automatic repeat request process is deprioritized, determining whether a configured grant retransmission timer for the hybrid automatic repeat request process has expired, the configured grant retransmission timer being started in a previous transmission of the transport block in the hybrid automatic repeat request process; in response to determining that the configured grant retransmission timer has expired, flushing the transport block from a buffer associated with the hybrid automatic repeat request process; The device according to any one of claims 1 to 3,

5. The at least one memory and the computer program code, together with the at least one processor, in the device further include: determining whether the transport block is permitted to be transmitted in the configuration grant; determining whether the user data is present in the transport block in response to determining that the transport block is permitted to be transmitted in the configuration grant; The device according to any one of claims 1 to 4,

6. 6. The device of claim 1, wherein the at least one memory and the computer program code, together with the at least one processor, further cause the device to: select the hybrid automatic repeat request process to perform a retransmission of the transport block in the configuration grant in response to a determination that the user data is contained within the transport block.

7. The selection of the hybrid automatic repeat request process comprises: assigning said hybrid automatic repeat request process a lower priority than one or more other hybrid automatic repeat request processes for retransmissions and / or one or more hybrid automatic repeat request processes for initial transmissions of transport blocks containing user data; or assigning said hybrid automatic repeat request process the lowest priority; The device according to any one of claims 1 to 6, wherein the device is de-prioritized by

8. 8. The device of claim 1, wherein the at least one memory and the computer program code, together with the at least one processor, further cause the device to select a hybrid automatic repeat request process from among the hybrid automatic repeat request processes for retransmission and / or initial transmission based on a priority of the hybrid automatic repeat request processes.

9. The device according to any one of claims 1 to 8, wherein the configuration grant is configured in an unlicensed band.

10. The device according to any one of claims 1 to 9, wherein the device comprises a terminal device.

11. 3. The device of claim 2, wherein the control information includes at least one of a Hybrid Automatic Repeat Request Process-Acknowledgement (HARQ-ACK), a Channel State Information (CSI), a Scheduling Request (SR), and a Configuration Grant Uplink Control Information (CG-UCI).

12. A communication method performed by a terminal device, comprising: determining through a hybrid automatic repeat request process that no user data is present within the transport block for retransmission; in response to determining that the user data is not present within the transport block, decreasing a priority of a selection of the hybrid automatic repeat request process for the retransmission in a configuration grant; A method comprising:

13. The absence of user data in the transport block is determined as follows: the transport block is generated only to contain control information; and the transport block is generated in response to an overlap between resources for the control information and a configuration grant that precedes the configuration grant; The method of claim 12 , wherein the at least one of the following is determined:

14. in response to determining that selection of the hybrid automatic repeat request process is deprioritized, flushing the transport block from a buffer associated with the hybrid automatic repeat request process; stopping at least one timer for the hybrid automatic repeat request process, the at least one timer including at least one of a configured grant timer and a configured grant retransmission timer started in a previous transmission of the transport block in the hybrid automatic repeat request process; The method of claim 12 or 13, further comprising:

15. in response to determining that selection of the hybrid automatic repeat request process is deprioritized, determining whether a configured grant retransmission timer for the hybrid automatic repeat request process has expired, the configured grant retransmission timer being started in a previous transmission of the transport block in the hybrid automatic repeat request process; in response to determining that the configured grant retransmission timer has expired, flushing the transport block from a buffer associated with the hybrid automatic repeat request process; The method of any one of claims 12 to 14, further comprising:

16. The method further includes determining whether the transport block is permitted to be transmitted in the configuration grant; 16. The method according to claim 12, wherein determining whether user data is not present in the transport block comprises determining whether the user data is not present in the transport block in response to a determination that the transport block is allowed to be transmitted in the configuration grant.

17. selecting the hybrid automatic repeat request process to perform a retransmission of the transport block in the configuration grant in response to determining that the user data is contained within the transport block. The method of any one of claims 12 to 16, further comprising:

18. The selection of the hybrid automatic repeat request process comprises: assigning said hybrid automatic repeat request process a lower priority than one or more other hybrid automatic repeat request processes for retransmissions and / or one or more hybrid automatic repeat request processes for initial transmissions of transport blocks containing user data; or A method according to any one of claims 12 to 17, wherein the hybrid automatic repeat request process is de-prioritized by assigning it the lowest priority.

19. selecting a hybrid automatic repeat request process from among the hybrid automatic repeat request processes for retransmissions and / or initial transmissions based on a priority of the hybrid automatic repeat request processes; The method of any one of claims 12 to 18, further comprising:

20. The method according to any one of claims 12 to 19, wherein the configuration grant is configured in an unlicensed band.

21. 14. The method of claim 13, wherein the control information includes at least one of a Hybrid Automatic Repeat Request Process-Acknowledgement (HARQ-ACK), a Channel State Information (CSI), a Scheduling Request (SR), and a Configuration Grant Uplink Control Information (CG-UCI).

22. An apparatus comprising: means for determining, via a hybrid automatic repeat request process, that no user data is present within a transport block for retransmission; means for decreasing a priority of a selection of the hybrid automatic repeat request process for the retransmission in a configuration grant in response to determining that the user data is not present in the transport block; 13. An apparatus comprising:

23. A computer readable storage medium comprising program instructions for causing an apparatus to carry out at least the method according to any one of claims 12 to 21.

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