WO2021232336A1

WO2021232336A1 - Methods, apparatuses and media for determining channel access priority

Info

Publication number: WO2021232336A1
Application number: PCT/CN2020/091514
Authority: WO
Inventors: Ping-Heng Kuo; Tao Tao; Jianhua Liu
Original assignee: Nokia Shanghai Bell Co., Ltd.; Nokia Solutions And Networks Oy; Nokia Technologies Oy
Priority date: 2020-05-21
Filing date: 2020-05-21
Publication date: 2021-11-25
Also published as: CN113966641A; CN113966641B

Abstract

Disclosed are methods for determining channel access priority. An example method may include receiving a configuration for determining a channel access priority or a channel access priority selection rule for an uplink transmission occasion based on at least a timing of the uplink transmission occasion, determining the channel access priority for the uplink transmission occasion based on the configuration, and transmitting a data unit using the uplink transmission occasion based on the determined channel access priority. Related apparatuses and computer readable media are also disclosed.

Description

METHODS, APPARATUSES AND MEDIA FOR DETERMINING CHANNEL ACCESS PRIORITY

TECHNICAL FIELD

Various example embodiments of the present disclosure generally relate to a field of telecommunication and in particular relate to methods, apparatuses, and computer readable media for determining channel access priority.

BACKGROUND

With development of communication, more and more technologies have been proposed, and more and more services are to be supported. A communication system may be enhanced to support various services. For example, a communication system such as a New Radio (NR or 5G) system may be anticipated to facilitate industrial operations, such as factory automation, which may involve time-sensitive communication (TSC) .

SUMMARY

In general, example embodiments of the present disclosure provide solutions for determining channel access priority. Embodiments that do not fall under the scope of the claims are to be interpreted as examples useful for understanding the disclosure.

In a first aspect, a method is disclosed. The method may be performed at an apparatus such as at least a part of a terminal device including a user equipment (UE) , and may include receiving a configuration for determining a channel access priority or a channel access priority selection rule for an uplink transmission occasion based on at least a timing of the uplink transmission occasion, determining the channel access priority for the uplink transmission occasion based on the configuration, and transmitting a data unit using the uplink transmission occasion based on the determined channel access priority.

In some embodiments, the timing of the uplink transmission occasion may be related to at least one of an index of uplink transmission occasion associated with a configured grant, a slot index, a mini-slot index, an orthogonal frequency division multiplexing symbol index, a subframe index, a frame index, or at least one factor for deriving an occurring time of the at least one uplink transmission occasion.

In some embodiments, the configuration for determining a channel access priority or a channel access priority selection rule may include at least one of a configuration for determining the channel access priority from a plurality of channel access priorities configured for the terminal device or a configuration for determining the channel access priority selection rule from a plurality of channel access priority selection rules configured for the terminal device.

In some embodiments, the plurality of channel access priority selection rules may include a first channel access priority selection rule and a second channel access priority selection rule different to the first channel access priority selection rule.

In some embodiments, the first channel access priority selection rule may be related to a content carried in the data unit, and the second channel access priority selection rule may be unrelated to the content carried in the data unit.

In some embodiments, the first channel access priority selection rule may be related to selecting a lower channel access priority associated with a content carried in the data unit, and the second channel access priority selection rule may be related to selecting a higher channel access priority associated the content carried in the data unit.

In some embodiments, the configuration may indicate an uplink transmission occasion associated with a first channel access priority or a first channel access priority selection rule, and the terminal device may determine the first channel access priority or the first channel access priority selection rule for the uplink transmission occasion indicated by the configuration, and/or determining a second channel access priority different from the first channel access priority or a second channel access priority selection rule different form the first channel access priority selection rule for at least one another uplink transmission occasion.

In some embodiments, the configuration may indicate a mapping between an uplink transmission occasion and a channel access priority or a channel access priority selection rule.

In a second aspect, a method is disclosed. The method may be performed at an apparatus such as at least a part of a network device (e.g. a base station) , and may include transmitting a configuration for determining a channel access priority or a channel access priority selection rule for an uplink transmission occasion based on at least a timing of the uplink transmission occasion, and receiving a data unit using the uplink transmission occasion.

In some embodiments, the configuration for determining a channel access priority or a channel access priority selection rule may include at least one of a configuration for determining a channel access priority from a plurality of channel access priority configured for a terminal device or a configuration for determining the channel access priority selection rule from a plurality of channel access priority selection rules configured for the terminal device.

In some embodiments, the configuration may indicate an uplink transmission occasion associated with a first channel access priority or a first channel access priority selection rule.

In a third aspect, an apparatus is disclosed. The apparatus may be at least a part of a terminal device, for example may be at least a part of a UE, and may include at least one processor and at least one memory. The at least one memory may include computer program code, and the at least one memory and the computer program code may be configured to, with the at least one processor, cause the apparatus to perform the method in the first aspect. In some embodiments, the at least one memory and the computer program code may be configured to, with the at least one processor, cause the apparatus to perform receiving a configuration for determining a channel access priority or a channel access priority selection rule for an uplink transmission occasion based on at least a timing of the uplink transmission occasion, determining the channel access priority for the uplink transmission occasion based on the configuration, and transmitting a data unit using the uplink transmission occasion based on the determined channel access priority.

In some embodiments, the configuration for determining a channel access priority or a channel access priority selection rule may include at least one of a configuration for determining the channel access priority from a plurality of channel access priorities configured for the apparatus or a configuration for determining the channel access priority selection rule from a plurality of channel access priority selection rules configured for the apparatus.

In some embodiments, the configuration may indicate an uplink transmission occasion associated with a first channel access priority or a first channel access priority selection rule, and the terminal device may determine the first channel access priority or the first channel access priority selection rule for the uplink transmission occasion indicated by the configuration, and/or determine a second channel access priority different from the first channel access priority or a second channel access priority selection rule different form the first channel access priority selection rule for at least one another uplink transmission occasion.

In a fourth aspect, an apparatus is disclosed. The apparatus may be at least a part of a terminal device, for example may be at least a part of a UE, and may include means for performing the method in the first aspect. In some embodiments, the apparatus may include means for: receiving a configuration for determining a channel access priority or a channel access priority selection rule for an uplink transmission occasion based on at least a timing of the uplink transmission occasion, determining the channel access priority for the uplink transmission occasion based on the configuration, and transmitting a data unit using the uplink transmission occasion based on the determined channel access priority.

In some embodiments, the configuration may indicate an uplink transmission occasion associated with a first channel access priority or a first channel access priority selection rule, and the determining the channel access priority for the uplink transmission occasion based on the configuration may include determining the first channel access priority or the first channel access priority selection rule for the uplink transmission occasion indicated by the configuration, and/or determining a second channel access priority different from the first channel access priority or a second channel access priority selection rule different form the first channel access priority selection rule for at least one another uplink transmission occasion.

In a fifth aspect, a computer readable medium is disclosed. The computer readable medium may include program instructions for causing an apparatus to perform the method in the first aspect. For example, the apparatus may be at least a part of the apparatus in the third aspect and/or the fourth aspect. In some embodiments, the program instructions may be used for causing the apparatus to perform receiving a configuration for determining a channel access priority or a channel access priority selection rule for an uplink transmission occasion based on at least a timing of the uplink transmission occasion, determining the channel access priority for the uplink transmission occasion based on the configuration, and transmitting a data unit using the uplink transmission occasion based on the determined channel access priority.

In a sixth aspect, an apparatus is disclosed. The apparatus may be at least a part of network device (e.g. a base station) , and may include at least one processor and at least one memory. The at least one memory may include computer program code, and the at least one memory and the computer program code may be configured to, with the at least one processor, cause the apparatus to perform the method in the second aspect. In some embodiments, the at least one memory and the computer program code may be configured to, with the at least one processor, cause the apparatus to perform transmitting a configuration for determining a channel access priority or a channel access priority selection rule for an uplink transmission occasion based on at least a timing of the uplink transmission occasion, and receiving a data unit using the uplink transmission occasion.

In a seventh aspect, an apparatus is disclosed. The apparatus may be at least a part of a network device (e.g. a base station) , and may include means for performing the method in the second aspect. In some embodiments, the apparatus may include means for: transmitting a configuration for determining a channel access priority or a channel access priority selection rule for an uplink transmission occasion based on at least a timing of the uplink transmission occasion, and receiving a data unit using the uplink transmission occasion.

In an eighth aspect, a computer readable medium is disclosed. The computer readable medium may include program instructions for causing an apparatus to perform the method in the second aspect. For example, the apparatus may be at least a part of the apparatus in the sixth aspect and/or the seventh aspect. In various embodiment, the program instructions may be used for causing the apparatus to perform transmitting a configuration for determining a channel access priority or a channel access priority selection rule for an uplink transmission occasion based on at least a timing of the uplink transmission occasion, and receiving a data unit using the uplink transmission occasion.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates survival time according to an embodiment of the present disclosure.

FIG. 2 illustrates an example method according to an embodiment of the present disclosure.

FIG. 3 illustrates an example of determining channel access priority according to an example method of the present disclosure.

FIG. 4 illustrates another example of determining a channel access priority according to an example method of the present disclosure.

FIG. 5 illustrates still another example of determining channel access priority according to an example method of the present disclosure.

FIG. 6 illustrates an example method according to an embodiment of the present disclosure.

FIG. 7 illustrates an example of determining a channel access priority for communication according to an example method of the present disclosure.

FIG. 8 illustrates an example apparatus according to an embodiment of the present disclosure.

FIG. 9 illustrates an example apparatus according to an embodiment of the present disclosure.

FIG. 10 illustrates an example apparatus according to an embodiment of the present disclosure.

FIG. 11 illustrates an example apparatus according to an embodiment of the present disclosure.

FIG. 12 illustrates another example of determining a channel access priority for communication according to an example method of the present disclosure.

FIG. 13 illustrates another example of determining a channel access priority for communication according to an example method of the present disclosure.

FIG. 14 illustrates another example of determining a channel access priority for communication according to an example method of the present disclosure.

DETAILED DESCRIPTION

Various communications supported in a communication system may have different traffic characteristics or quality of service requirements. For example, traffic patterns of TSC may be periodic with fixed burst size. In addition, many industrial applications, , and TSC use cases, may have a new requirement related to survival time. The survival time means a time interval during which an application consuming a communication service may continue without an anticipated message or may recover from failure. For example, the survival time may be expressed as a time period or maximum number of consecutive packet delivery failure that an application may tolerate.

On the other hand, a communication system may operate on an unlicensed band. For a transmission in an unlicensed spectrum, a listen-before-talk (LBT) procedure may be performed to avoid possibly impacting other co-existing radio access (RA) technologies such as Wi-Fi. For example, the transmission in an unlicensed spectrum may be allowed if a transmitter has identified a channel in the unlicensed spectrum as free, e.g., by monitoring it for a certain amount of time. The channel may be subsequently used for a maximum channel occupancy time (COT) .

A mechanism used for channel access may depend on a channel access priority (CAP) . As an example rather than limitation, the channel access priority may be represented in a form of a channel access priority class (CAPC) . For instance, a contention window size of a LBT (e.g. a Category 4 LBT) and the maximum COT may depend on the channel access priority class (CAPC) which may be derived based on the contents carried in the data unit to be transmitted. For example, 4 CAPC values (1, 2, 3, and 4) may be defined, wherein a lower CAPC value corresponding to a higher channel access priority (CAP) may promote a more rapid access to the unlicensed spectrum due to more aggressive LBT procedures, and a higher CAPC value corresponding to a lower CAP may result in a slow access to the unlicensed spectrum. It should be appreciated, in some example embodiments, a higher CAP may alternatively be represented by a higher priority value or index.

Then, when operating in an unlicensed spectrum, a channel access priority may determine a probability of success in channel access, or a probability of LTB failure. On the other hand, the survival time of an application may be related to consecutive LBT failures. For example, as shown in FIG. 1, if the CAPC value is determined as 4 and the LBT fails during a period T1, the service during the following period T2 may enter a status of “Down” (a state where the service is unavailable) from a previous status of “Up” (a state where the service is available) , and the application may enter a survival time during the period of T2. Then, if LBT succeeds during the period T2, the service during the following period T3 may return to the status of “Up” , and the application may recover back to the status of “Up” . However, if both LBTs during the following two periods T3 and T4 fails, the application may suffer from a transmission failure at least during the period T5, and the survival time is violated. That is, consecution LBT failures may result in a violation of the survival time requirement and consequently an unsatisfying application layer experience.

For example, the survival time may be ensured by avoiding late delivery of the packets consecutively. For example, the packets of the traffic flow may be transmitted with a high CAP or a low CAPC value, for example, the highest CAP or the lowest CAPC. However, in such a manner, for example, persistent and aggressive interference may be created to other co-existing technologies (e.g. Wi-Fi) operating in the unlicensed spectrum.

In some embodiments, instead of transmitting every packet based on a default CAPC level or CAPC selection rule, a transmitter can occasionally (e.g., based on certain event which may relate to a survival time, or based on a cyclic pattern which may related to the required survival time) transmits a specific packet with an alternative CAPC mechanism to increase probability of successful LBT and hence on-time packet delivery before survival time expiration.

FIG. 2 illustrates an example method 200 for determining CAP according to an embodiment. The method may be performed in an apparatus such as at least a part of a terminal device, for example may be at least a part of a UE.

As shown in FIG. 2, the example method 200 may include a step 210 of receiving a configuration for determining a CAP or a CAP selection rule for an uplink transmission occasion based on at least a timing of the uplink transmission occasion, a step 220 of determining the CAP for the uplink transmission occasion based on the configuration, and a step 230 of transmitting a data unit (e.g. a Media Access Control Packet Data Unit or MAC PDU) using the uplink transmission occasion based on the determined CAP.

In the example method 200, instead of transmitting packets using a single CAP or CAP selection rule (e.g., a default CAP or a default CAP selection rule, or a CAP determined according to the contents of the packets) , the CAP (or corresponding CAPC) or the CAP selection rule is determined dynamically for respective uplink transmission occasions based on a received configuration and one or more conditions, and the data unit may be transmitted using the uplink transmission occasion based on the CAP determined for the specific uplink transmission occasion. The determination may be based on a timing of the uplink transmission occasion. Thus, in some embodiments, the CAP (or corresponding CAPC) or the CAP selection rule may be modified dynamically or timely, and a faster access to an unlicensed channel may be enabled for some transmission occasions, so that data with survival time requirement may be delivered over the air interface of unlicensed band as soon as possible when to prevent survival time violation. Also, for example, the probability of LBT failure that may lead to survival time violation which may halts the operation of the application may be reduced, and persistent and aggressive interference to other co-existing technologies (e.g. Wi-Fi) in the unlicensed spectrum may be minimized. In some embodiments, the method may be utilized to meet a latency requirement of an application.

In some embodiments, the uplink transmission occasion may be associated with a configured grant (CG) or a semi-persistent scheduling (SPS) . In some embodiments, CG or SPS may be used for radio resource allocation for TSC due to their periodic nature.

FIG. 3 (A) illustrates an example of determining channel access priority according to an example method 200 of the present disclosure. As shown in FIG. 3 (A) , in the step 210 of the example method 200, a UE 310 may receive a configuration for determining a CAP or a CAP selection rule for at least one uplink transmission occasion with index of O ₁, O ₂, …, O _N (N being an integer larger than 0) from a base station (e.g. gNB in the NR system) 320.

In some embodiments, the configuration may include a configuration for determining a CAP from a plurality of CAP configured for the UE 310 and/or a configuration for determining a CAP selection rule from a plurality of CAP selection rules configured for the UE 310.

In an embodiment, the plurality of CAPs may include at least two different CAPs. For example, at least two different CAPs (or different CAPCs) may be configured for one or more logical channels (LCHs) so that the CAP or CAPC for the LCH (s) may be switched from one to another according to one or more conditions, for example, based on at least a timing of an uplink transmission occasion. In some embodiments, at least two different CAPs (or different CAPCs) may be configured for a CG (or SPS) , so that the CAP or CAPC for different transmission occasions associated with the CG (also referred to as CG occasions) may be dynamically determined according to one or more conditions, e.g., based on timing of the transmission occasions.

Likewise, at least two different CAP (or CAPC) selection rules may be configured for one or more LCHs, and/or at least two different CAP (or CAPC) selection rules may be configured for a CG, so that the CAP (or CAPC) selection rule for different transmission occasions associated with the CG (or LCHs) may be dynamically determined according to one or more conditions.

For example, a first CAP of the at least two different CAPs may be related to a content carried in the data unit, and a second CAP of the at least two different CAPs may be unrelated to the content carried in the data unit. For example, the first CAP may be a lower CAP, e.g. the lowest possible CAP, and the second CAP may be a higher CAP, e.g. the highest possible CAP. In an embodiment, the first CAP may be a CAP determined based on a characteristic of a content (e.g., a traffic or a control message) carried in the data unit, while the second CAP may be a CAP determined regardless of the characteristic.

For example, in connection with the left part of FIG. 3 which is also noted as FIG. 3 (A) here below, the plurality of CAP configured for the UE 310 may include CAP ₁, CAP ₂…and CAP _N. For example, CAP ₁ and CAP ₂ may have the same CAP value corresponding to CAPC 4, CAP ₃ may have a CAP value corresponding to CAPC 1, CAP ₄ and CAP ₅ may have the same CAP value corresponding to CAPC 4, CAP ₆ may have a CAP value corresponding to CAPC 1, or the like.

In an embodiment, the plurality of CAP selection rules may include at least two different CAP selection rules, so that the CAP/CAPC selection rules may be switched from one to another according to one or more conditions, for example, based on at least a timing of the uplink transmission occasion.

For example, a first CAP selection rule of the at least two different CAP selection rules may be related to a content carried in the data unit. For example, the first CAP selection rule may be based on a characteristic of a content (e.g., a traffic or a control message) carried in the data unit. A second CAP selection rule may be unrelated to the content carried in the data unit. For example, the first rule may be related to selecting a lower (e.g. the lowest) CAP associated with the content carried in the data unit (e.g. which LCHs are mapped to this data unit) , and the second CAP selection rule may be related to selecting a highest possible CAP without concerning the content carried in the data unit. It should be appreciated that the timing of an uplink transmission occasion may be identified using an index of an corresponding uplink grant, slot, mini-slot, frame, subframe, symbol and the like.

For example, in connection with FIG. 3 (A) , the plurality of CAP selection rules configured for the UE 310 may include deciding CAP ₁ for the uplink transmission occasion with an index of O ₁, deciding CAP ₂ for the uplink transmission occasion with an index of O ₂, …, and deciding CAP _N for the uplink transmission occasion with an index of O _N, or the like. For example, the uplink transmission occasion with an index of O ₂ may be an occasion following the uplink transmission occasion with an index of O ₁, the uplink transmission occasion with an index of O ₃ may be an occasion following the uplink transmission occasion with an index of O ₂, and the like, so as to form a sequence in an order of the indices. For examples, O ₁, O ₂, …, O _N may be a series of uplink transmission occasions pertaining to a single configured grant configuration. In another examples, O ₁, O ₂, …, O _N may be series of uplink transmission occasions such as slots, orthogonal frequency division multiplexing symbols, and so on.

For example, the plurality of CAP selection rules configured the UE 310 may include, but are not limited to, a rule for deciding the CAP or CAPC for the uplink transmission occasion with at least one index (e.g. O ₃, or O ₆, or the like) based on the highest CAP or the lowest CAPC of logical channels (LCHs) mapped to the data unit prepared for this uplink transmission occasion, and a rule for deciding the CAP or CAPC for the uplink transmission occasion with at least one another index (e.g. O ₁, or O ₂, or O ₄, or O ₅, or the like) based on the lowest CAP or the highest CAPC of LCHs mapped to the data unit prepared for this uplink transmission occasion. For another example, the plurality of CAP selection rules configured the UE 310 may include, but are not limited to, a rule for deciding the CAP or CAPC for the uplink transmission occasion with at least one index (e.g. O ₃, or O ₆, or the like) to be the highest possible CAP or the lowest CAPC, and a rule for deciding the CAP or CAPC for the uplink transmission occasion with at least one another index (e.g. O ₁, or O ₂, or O ₄, or O ₅, or the like) to be the lowest possible CAP or the highest CAPC, and the like.

In an embodiment, the configuration received from the network device at step 210 may indicate a mapping between an uplink transmission occasion and a CAP or a CAP selection rule. For example, the configuration may indicate using CAP ₁ for the uplink transmission occasion O ₁, using CAP ₂ for the uplink transmission occasion O ₂, and using CAP _N for the uplink transmission occasion O _N, or the like. In an embodiment, the configuration may indicate using a first CAP selection rule for the ith transmission occasion, and using a second CAP selection rule for other transmission occasions.

In some embodiments, the configuration may only indicate a set of transmission occasions (e.g., every third transmission occasions) associated with a fist CAP or CAP selection rule. Then, for example, in the step 220, the UE 310 may determine a first CAP for the uplink transmission occasion indicated by the configuration. Alternatively, the UE 310 may determine a first CAP selection rule based on the configuration, and then determine a first CAP for the uplink transmission occasion indicated by the configuration based on the first CAP selection rule. In addition or instead, in the step 220, for uplink transmission occasions other than the indicates set of transmission occasions, the UE 310 may determine a second CAP different from the first CAP, or determine a second CAP selection rule different form the first CAP selection rule and use the second CAP selection rule to determine a second CAP. In some embodiments, the first CAP may be high than the second CAP.

For example, as shown in FIG. 3 (A) , in the step 220, the UE 310 may determine CAP ₁ (or corresponding CAPC) for the uplink transmission occasion O ₁ or a CAP/CAPC selection rule for O ₁ based on the configuration received in the step 210. Similarly, the UE 310 may determine CAP ₂ (or corresponding CAPC) for the uplink transmission occasion O ₂ following the the uplink transmission occasion O ₁ or a CAP/CAPC determine rule for O ₂ based on the configuration, where, for example, CAP ₂ (or corresponding CAPC) or the CAP/CAPC determine rule for O ₂ may be either the same as or different from CAP ₁ (or corresponding CAPC) or the CAP/CAPC determine rule for O ₁. Similarly, the UE 310 may determine CAP _N (or corresponding CAPC) for the uplink transmission occasion O _N after the uplink transmission occasion O ₁ or a CAP/CAPC determine rule for O _N based on the configuration, where, for example, CAP _N (or corresponding CAPC) or the CAP/CAPC determine rule for O _N may be either the same as or different from CAP ₁ (or corresponding CAPC) or the CAP/CAPC determine rule for O ₁.

Then, in the step 230, as shown in FIG. 3 (A) , the UE 310 may transmit a data unit DU ₁ using the uplink transmission occasion O ₁ based on the determined CAP ₁. Similarly, for example, the UE 310 may transmit a data unit DU ₂ using the uplink transmission occasion O ₂ based on the determined CAP ₂ in the step 230, transmit a data unit DU _N using the uplink transmission occasion O _N based on the determined CAP _N in the step 230, and the like.

It is appreciated that execution of the steps in the example method 200 may be not limited to the example in FIG. 3 (A) . In another example, the UE 310 may perform the

steps

220 and 230 for respective occasions, separately. For example, as shown in the right part of FIG. 3 which is also noted as FIG. 3 (B) here below, the UE 310 may perform the step 220 to determine to use CAP ₁ for the uplink transmission occasion O ₁ and then perform the step 230 to transmit the data unit DU ₁ using the uplink transmission occasion O ₁ based on CAP ₁, and then perform the step 220 to determine to use CAP ₂ for the uplink transmission occasion O ₂ and then perform the step 230 to transmit the data unit DU ₂ using the uplink transmission occasion O ₂ based on CAP ₂, and so on.

Thus, instead of transmitting respective packets using a CAP/CAPC or a CAP/CAPC selection rule based on the contents of the data unit or using a default CAP/CAPC or a default CAP/CAPC selection rule, the CAP/CAPC and/or the CAP/CAPC selection rule may determined dynamically for respective uplink transmission occasions based on a received configuration and one or more conditions, and the data unit (e.g. MAC PDU) may be transmitted using the uplink transmission occasion based on the CAP determined for the uplink transmission occasion. That is, the CAP/CAPC and/or the CAP/CAPC selection rule may be modified dynamically or timely, so that a faster access to an unlicensed channel may be enabled for some transmission occasions. As a result, in some embodiments, data with survival time requirement may be delivered over the air interface of unlicensed band as soon as possible.

In some embodiments, the CAP/CAPC or CAP/CAPC selection rule may be determined for an uplink transmission occasion based on one or more conditions, for example, based on at least a timing of the uplink transmission occasion.

In some embodiments, the timing of the uplink transmission occasion may be related to at least one of an index of uplink transmission occasion associated with an configured grant (CG) , a slot index, a mini-slot index, an orthogonal frequency division multiplexing symbol index, a subframe index, or a frame index.

For example, the timing of a CG occasion may be also derived based on at least one factor. For example, after an uplink grant is configured for a CG, the UE may consider sequentially that the N ^th uplink grant occurs in a symbol based on one or more factors such as the number of slots per frame, the number of symbols per slot, slot number in the frame, the symbol number in the slot, and so on.

For example, the configuration for determining a channel access priority or a channel access priority selection rule may include multiple CAPs or CAPCs for one or more LCHs, for example including a first CAP derived based on the contents carried in the data units to be transmitted via the uplink and a second CAP unrelated to the contents carried in the data units to be transmitted via the uplink which is higher than the first CAP (e.g. the highest possible CAP) , In the example shown in FIG. 4, in a case where a CG with survival time requirement is configured, and there are a plurality of transmission occasions (also referred to as CG occasions) 410-460 associated with the CG. the UE 310 may process the CG after receiving the configuration in the step 210, and may determine the CAPs or CAPCs for respective CG occasions based on the timings of respective CG occasions, and for example, based on the index of the CG occasion. The UE 310 may switch the CAPs or CAPCs of the LCH(s) from one to another under one or more conditions. For example, the UE 310 may apply a specific CAP or CAP selection rule different from a default one for at least one CG occasion with the corresponding index satisfying a predetermined condition, and/or when the UE 310 has received a predetermined number of re-transmission grant for this CG consecutively, and so on.

For example, as shown in FIG. 4, in an embodiment, the UE 310 determines the second CAP (which may be a higher CAP) for those CG occasions with indices being a integer multiple of 3 and the first CAP for the other CG occasions, so that the first CAP (which may be a default CAP lower than the second CAP) is determined for the CG occasions 410 (with an uplink 1) , 420 (with an index 2) , 440 (with an index 4) , 450 (with an index 5) , and so on, and the second CAP is determined for the CG occasions 430 (with an index 3) , 460 (with an index 6) , and so on. Then, the UE 310 may transmit data units using the

CG occasions

410, 420, 440, 450 and so on based on the first CAP, and transmit data units using the

CG occasions

430, 460, and so on based on the second CAP.

As another example, if the configuration for determining a channel access priority or a channel access priority selection rule includes multiple CAP/CAPC selection rules, for example including a first CAP/CAPC selection rule indicating to use a first CAP derived based on the contents carried in the data units to be transmitted via the uplink and a second CAP/CAPC selection rule indicating to use a second CAP which is unrelated to the contents carried in the data units to be transmitted via the uplink. The second CAP may be higher than the first CAP (e.g. the highest possible CAP) . In the example as shown in FIG. 5, a CG with survival time requirement is configured, and there are a plurality of transmission occasions 510-560 associated with the CG. The UE 310 may process the CG after receiving the configuration in the step 210, and may determine the CAP/CAPC selection rules for respective CG occasions based on the timings of respective CG occasions, and for example, based on the index of the CG configuration, may switch the CAP/CAPC selection rules from one to another under one or more conditions. For example, UE 310 may apply a specific CAPC selection rule for at least one CG occasion with the corresponding index satisfying a predetermined condition, when the UE 310 has received a predetermined number of re-transmission grant for this CG consecutively, and so on.

In an embodiment, as shown in FIG. 5, the UE 310 determines the second CAP/CAPC selection rule for those CG occasions with indices being a integer multiple of 2 and the first CAP/CAPC selection rule for the other CG occasions, so that the first CAP selection rule is determined for the CG occasions 510 (with an index 1) , 530 (with an index 3) , 550 (with an index 5) , and so on, and the second CAP selection rule is determined for the CG occasions 520 (with an index 2) , 540 (with an index 4) , 560 (with an index 6) , and so on. Then, the UE 310 may transmit data units using the

CG occasions

510, 530, 550 and so on based on the CAP selected in accordance to the first CAP selection rule, and may transmit data units using the

CG occasions

520, 540, 560, and so on based on the CAP selected in accordance to the second CAP selection rule.

It is appreciated that the timing for switching CAPs/CAPCs or CAP/CAPC selection rules may be not limited to the above examples, and the frequency of using alternative CAPC selection rule or alternative CAP may be configured, or determined depending on a characteristic of a corresponding application, e.g., a survival time for the data traffic from a LCH mapping to a CG. Thus, in some embodiments, at least one packet from this LCH may be transmitted with higher CAP during at least one survival time, and a lower probability of LBT failure which may result in unsuccessful on-time delivery and survival time violation may be achieved.

In addition to or in lieu of at least a timing of an uplink transmission occasion, the CAPs/CAPCs or CAP/CAPC selection rules may be determined for an uplink transmission occasion in response to one or more other conditions, for example, a predetermined number of consecutive LBT failures, a reception of a control signal (e.g. a downlink control information or DCI) from the base station 320 indicating a switch of CAP/CAP selection rule, detection of beam failure or radio link failure, a detection of a predetermined number of consecutive packet errors and/or re-transmissions and/or negative acknowledgement, characteristics of data (e.g. packet sequence number associated to the data, Quality of Service (QoS) flow ID associated to the data) carried in the data unit to be transmitted on the uplink transmission occasion, priority/type of uplink control information (UCI) such as Hybrid Automatic Repeat Request Acknowledgement (HARQ-ACK) to be multiplexed into the transmission on the uplink transmission occasion, and so on.

Further, in an embodiment, a timer in the UE 310 may be started or restarted for example upon changing from a first CAP/CAPC or a first CAP/CAPC selection rule to a second CAP/CAPC or a second CAP/CAPC selection rule, and UE may fall back to the first CAP/CAPC or the first CAP/CAPC selection rule in response to, for example, an expiry of the timer, a signal from the base station, and so on.

FIG. 6 illustrates an example method 600 which may be performed for example in an apparatus such as at least a part of a network device (e.g. the base station 320 in the above examples) , corresponding to the example method 200 performed in the UE.

As shown in FIG. 6, the example method 600 may include a step 610 of transmitting a configuration for determining a CAP or a CAP selection rule for an uplink transmission occasion based on at least a timing of the uplink transmission occasion, which may correspond to the step 210 of the example method 200, and a step 620 of receiving a data unit using the uplink transmission occasion, which may correspond to the step 230 of the example method 200.

It is appreciated that various features and aspects of the example method 200 may be also included in or combined with or applied to the example method 600.

For example, in some embodiments, the timing of the uplink transmission occasion may be related to at least one of an index of uplink transmission occasion associated with a configured grant, a slot index, a mini-slot index, an orthogonal frequency division multiplexing symbol index, a subframe index, a frame index, or at least one factor for deriving an occurring time of the at least one uplink transmission occasion.

In some embodiments, the configuration may indicate a set of uplink transmission occasions (which include one or more transmission occasions) , associated with a first channel access priority or a first channel access priority selection rule. The first channel access priority or a first channel access priority selection rule is different from a second channel access priority or a second channel access priority selection rule associated with at least one another uplink transmission occasion. For example, the second CAP may be a default CAP (or a CAP determined based on content of a corresponding data unit) , while the first CAP may be a higher CAP than the default one.

For example, the relationship between the steps in the example method 600 and the steps in the example method 200 may be illustrated in FIG. 7.

Further, as shown in FIG. 7, in some embodiments, the example method 600 may also include a step of receiving information on characteristics of a traffic flow, for example based on TSC Assistance Information (TSCAI) from a core network (CN) 710, for example before the step 610, so that the base station 320 may restrict the mapping of a LCH corresponding to this traffic flow to a CG satisfying the traffic pattern and reliability target.

FIG. 8 illustrates an example apparatus 800 for determining CAP in an embodiment, which, for example, may be implemented in or as at least a part of a terminal device, e.g. the UE 310 in the above examples.

As shown in FIG. 8, the example apparatus 800 may include at least one processor 810 and at least one memory 820 that may include computer program code 830. The at least one memory 820 and the computer program code 830 may be configured to, with the at least one processor 810, cause the apparatus 800 at least to perform at least the example method 200 described above.

In various example embodiments, the at least one processor 810 in the example apparatus 800 may include, but not limited to, at least one hardware processor, including at least one microprocessor such as a central processing unit (CPU) , a portion of at least one hardware processor, and any other suitable dedicated processor such as those developed based on for example Field Programmable Gate Array (FPGA) and Application Specific Integrated Circuit (ASIC) . Further, the at least one processor 810 may also include at least one other circuitry or element not shown in FIG. 8.

In various example embodiments, the at least one memory 820 in the example apparatus 800 may include at least one storage medium in various forms, such as a volatile memory and/or a non-volatile memory. The volatile memory may include, but not limited to, for example, a random-access memory (RAM) , a cache, and so on. The non-volatile memory may include, but not limited to, for example, a read only memory (ROM) , a hard disk, a flash memory, and so on. Further, the at least memory 820 may include, but are not limited to, an electric, a magnetic, an optical, an electromagnetic, an infrared, or a semiconductor system, apparatus, or device or any combination of the above.

Further, in various example embodiments, the example apparatus 800 may also include at least one other circuitry, element, and interface, for example at least one I/O interface, at least one antenna element, and the like.

In various example embodiments, the circuitries, parts, elements, and interfaces in the example apparatus 800, including the at least one processor 810 and the at least one memory 820, may be coupled together via any suitable connections including, but not limited to, buses, crossbars, wiring and/or wireless lines, in any suitable ways, for example electrically, magnetically, optically, electromagnetically, and the like.

It is appreciated that the structure of the apparatus on the side of the UE is not limited to the above example apparatus 800.

FIG. 9 illustrates another example apparatus 900 for determining CAP in an embodiment, which, for example, may be implemented in or as at least a part of a terminal device, e.g. the UE 310 in above examples.

As shown in FIG. 9, the example apparatus 900 may include means 910 for performing the step 210 of the example method 200, means 920 for performing the step 220 of the example method 200, and means 930 for performing the step 230 of the example method 200. In one or more another example embodiments, at least one I/O interface, at least one antenna element, and the like may also be included in the example apparatus 900.

In some example embodiments, the means comprises at least one processor; and at least one memory including computer program code, the at least one memory and computer program code configured to, with the at least one processor, cause the performance of the apparatus 900.

In some example embodiments, examples of means in the example apparatus 900 may include circuitries. For example, an example of means 910 may include a circuitry configured to perform the step 210 of the example method 200, an example of means 920 may include a circuitry configured to perform the step 220 of the example method 200, and an example of means 930 may include a circuitry configured to perform the step 230 of the example method 200. In some example embodiments, examples of means may also include software modules and any other suitable function entities.

The term “circuitry” throughout this disclosure may refer to one or more or all of the following: (a) hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry) ; (b) combinations of hardware circuits and software, such as (as applicable) (i) a combination of analog and/or digital hardware circuit (s) with software/firmware and (ii) any portions of hardware processor (s) with software (including digital signal processor (s) ) , software, and memory (ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) ; and (c) hardware circuit (s) and or processor (s) , such as a microprocessor (s) or a portion of a microprocessor (s) , that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation. This definition of circuitry applies to one or all uses of this term in this disclosure, including in any claims. As a further example, as used in this disclosure, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and/or firmware. The term circuitry also covers, for example and if applicable to the claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.

FIG. 10 illustrates an example apparatus 1000 which, for example, may be at least a part of a network device, e.g. the base station 320 in the above examples.

As shown in FIG. 10, the example apparatus 1000 may include at least one processor 1010 and at least one memory 1020 that may include computer program code 1030. The at least one memory 1020 and the computer program code 1030 may be configured to, with the at least one processor 1010, cause the apparatus 1000 at least to perform at least the example method 600 described above.

In various example embodiments, the at least one processor 1010 in the example apparatus 1000 may include, but not limited to, at least one hardware processor, including at least one microprocessor such as a CPU, a portion of at least one hardware processor, and any other suitable dedicated processor such as those developed based on for example FPGA and ASIC. Further, the at least one processor 1010 may also include at least one other circuitry or element not shown in FIG. 10.

In various example embodiments, the at least one memory 1020 in the example apparatus 1000 may include at least one storage medium in various forms, such as a volatile memory and/or a non-volatile memory. The volatile memory may include, but not limited to, for example, a RAM, a cache, and so on. The non-volatile memory may include, but not limited to, for example, a ROM, a hard disk, a flash memory, and so on. Further, the at least memory 1020 may include, but are not limited to, an electric, a magnetic, an optical, an electromagnetic, an infrared, or a semiconductor system, apparatus, or device or any combination of the above.

Further, in various example embodiments, the example apparatus 1000 may also include at least one other circuitry, element, and interface, for example at least one I/O interface, at least one antenna element, and the like.

In various example embodiments, the circuitries, parts, elements, and interfaces in the example apparatus 1000, including the at least one processor 1010 and the at least one memory 1020, may be coupled together via any suitable connections including, but not limited to, buses, crossbars, wiring and/or wireless lines, in any suitable ways, for example electrically, magnetically, optically, electromagnetically, and the like.

It is appreciated that the structure of the apparatus on the side of the base station is not limited to the above example apparatus 1000.

FIG. 11 illustrates another example apparatus 1100 for determining CAP in an embodiment, which, for example, may be at least a part of a network device, e.g. the base station 320 in the above examples.

As shown in FIG. 11, the example apparatus 1100 may include means 1110 for performing the step 610 of the example method 600 and means 1120 for performing the step 620 of the example method 600. In one or more another example embodiments, at least one I/O interface, at least one antenna element, and the like may also be included in the example apparatus 1100.

In some example embodiments, the means comprises at least one processor; and at least one memory including computer program code, the at least one memory and computer program code configured to, with the at least one processor, cause the performance of the apparatus 1100.

In some example embodiments, examples of means in the example apparatus 1100 may include circuitries. For example, an example of means 1110 may include a circuitry configured to perform the step 610 of the example method 600, and an example of means 1120 may include a circuitry configured to perform the step 620 of the example method 600. In some example embodiments, examples of means may also include software modules and any other suitable function entities.

It is appreciated that the disclosure is not limited to the above example embodiments.

For example, FIG. 12 illustrates another example of determining a channel access priority for communication according to an example variation 1200 of the example method 200.

As shown in FIG. 12, in this example variation 1200, the step 210 may include an operation 1210 of receiving a first CAP and a second CAP for a LCH. The step 210 may also include an operation 1220 of receiving configuration relating to condition (s) to trigger a CAP adaption/switching, for example, based on at least the timing of a timing of the uplink transmission occasion. Then, the step 220 may include an operation 1230 of processing a CG and an operation 1240 of checking whether the trigger conditions are met. In the step 230, if “No” is returned by an operation 1240, an operation 1250 in the step 230 may be performed to use the first CAP (e.g. a default CAP, which may be determined based on the contents carried in the packets transmitted via the LCH) for the LCH. If “Yes” is returned by the step 1240, an operation 1260 in the step 230 may be performed to use the second CAP (e.g. a CAP unrelated to the contents carried in the packets transmitted via the LCH) for the LCH. In some embodiments, a timer could start upon adopting of the second CAP, and the UE may change the CAP of the LCH back to the first CAP (default) upon expiration of the timer.

FIG. 13 illustrates another example of determining a channel access priority for communication according to an example variation 1300 of the example method 200.

As shown in FIG. 13, in this example variation 1300, configuration for determining a CAP selection rule for an uplink transmission occasion based on at least a timing of the uplink transmission occasion may be received in the step 210. Then, in the step 220, an operation 1310 may be performed to check whether multiple CAP selection rules are included in the configuration. If no, the example variation 1300 may proceed to an operation 1330 in the step 230 to use the first set of CAP selection rules (e.g. the default set of CAP selection rules) ; otherwise, the example variation 1300 may proceed to another operation 1320 in the step 220 to check whether the trigger conditions are met. In the step 230, if “No” is returned by an operation 1320, an operation 1330 in the step 230 may be performed to use the first set of CAP selection rules (e.g. the default CAP selection rules) . If “Yes” is returned by the step 1320, an operation 1340 in the step 230 may be performed to use a second set of CAP selection rules.

FIG. 14 illustrates a sequence chart between the UE 310 and the base station 320, which may correspond to the above example variation 1300.

As shown in FIG. 14, in the step 210, the UE 310 may receive a plurality of sets of CAP selection rules from the base station 320, and may also receive conditions for switching the CAP selection rules. Then, in the step 220, the UE 310 may process CG physical uplink shared channel (PUSCH) , check if the conditions are met, and determine the CAP selection rule to be used for a CG occasion according to the checking results. Then, in the step 230, the UE 310 may perform LBT and/or transmissions of the CG PUSCH based on the derived CAP.

Another example embodiment may be related to a computer readable medium having such computer program codes or instructions stored thereon. In various example embodiments, such a computer readable medium may include at least one storage medium in various forms such as a volatile memory and/or a non-volatile memory. The volatile memory may include, but not limited to, for example, a RAM, a cache, and so on. The non-volatile memory may include, but not limited to, a ROM, a hard disk, a flash memory, and so on. The non-volatile memory may also include, but are not limited to, an electric, a magnetic, an optical, an electromagnetic, an infrared, or a semiconductor system, apparatus, or device or any combination of the above.

Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise, ” “comprising, ” and the like are to be construed in an inclusive sense, as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to. ” The word “coupled” , as generally used herein, refers to two or more elements that may be either directly connected, or connected by way of one or more intermediate elements. Likewise, the word “connected” , as generally used herein, refers to two or more elements that may be either directly connected, or connected by way of one or more intermediate elements. Additionally, the words “herein, ” “above, ” “below, ” and words of similar import, when used in this application, shall refer to this application as a whole and not to any particular portions of this application. Where the context permits, words in the description using the singular or plural number may also include the plural or singular number respectively. For example, “aCAP selection rule” in the above examples may also mean “aset of CAP selection rules” , the “first CAP selection rule” in the above examples may also mean the “first set of CAP selection rules” , the “second CAP selection rule” in the above examples may also mean the “second set of CAP selection rules” , or the like. The word “or” in reference to a list of two or more items, that word covers all of the following interpretations of the word: any of the items in the list, all of the items in the list, and any combination of the items in the list.

Moreover, conditional language used herein, such as, among others, “can, ” “could, ” “might, ” “may, ” “e.g., ” “for example, ” “such as” and the like, unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements and/or states. Thus, such conditional language is not generally intended to imply that features, elements and/or states are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without author input or prompting, whether these features, elements and/or states are included or are to be performed in any particular embodiment.

As used herein, the term “communication system” refers to a system following any suitable communication standards, such as New Radio (NR) , Long Term Evolution (LTE) , LTE-Advanced (LTE-A) , Wideband Code Division Multiple Access (WCDMA) , High-Speed Packet Access (HSPA) , Narrow Band Internet of Things (NB-IoT) and so on. Furthermore, the communications between a terminal device and a network device in the communication system may be performed according to any suitable generation communication protocols, including, but not limited to, the first generation (1G) , the second generation (2G) , 2.5G, 2.75G, the third generation (3G) , the fourth generation (4G) , 4.5G, the future fifth generation (5G) communication protocols, and/or any other protocols either currently known or to be developed in the future. Embodiments of the present disclosure may be applied in various communication systems. Given the rapid development in communications, there will of course also be future type communication technologies and systems with which the present disclosure may be embodied. It should not be seen as limiting the scope of the present disclosure to only the aforementioned system.

As used herein, the term “network device” refers to a node in a communication network via which a terminal device accesses the network and receives services therefrom. The network device may refer to a base station (BS) or an access point (AP) , for example, a node B (NodeB or NB) , an evolved NodeB (eNodeB or eNB) , a NR NB (also referred to as a gNB) , a Remote Radio Unit (RRU) , a radio header (RH) , a remote radio head (RRH) , a relay, an Integrated and Access Backhaul (IAB) node, a low power node such as a femto, a pico, a non-terrestrial network (NTN) or non-ground network device such as a satellite network device, a low earth orbit (LEO) satellite and a geosynchronous earth orbit (GEO) satellite, an aircraft network device, and so forth, depending on the applied terminology and technology.

The term “terminal device” refers to any end device that may be capable of wireless communication. By way of example rather than limitation, a terminal device may also be referred to as a communication device, user equipment (UE) , a Subscriber Station (SS) , a Portable Subscriber Station, a Mobile Station (MS) , or an Access Terminal (AT) . The terminal device may include, but not limited to, a mobile phone, a cellular phone, a smart phone, voice over IP (VoIP) phones, wireless local loop phones, a tablet, a wearable terminal device, a personal digital assistant (PDA) , portable computers, desktop computer, image capture terminal devices such as digital cameras, gaming terminal devices, music storage and playback appliances, vehicle-mounted wireless terminal devices, wireless endpoints, mobile stations, laptop-embedded equipment (LEE) , laptop-mounted equipment (LME) , USB dongles, smart devices, wireless customer-premises equipment (CPE) , an Internet of Things (loT) device, a watch or other wearable, a head-mounted display (HMD) , a vehicle, a drone, a medical device and applications (e.g., remote surgery) , an industrial device and applications (e.g., a robot and/or other wireless devices operating in an industrial and/or an automated processing chain contexts) , a consumer electronics device, a device operating on commercial and/or industrial wireless networks, and the like. In the following description, the terms “terminal device” , “communication device” , “terminal” , “user equipment” and “UE” may be used interchangeably.

While some embodiments have been described, these embodiments have been presented by way of example, and are not intended to limit the scope of the disclosure. Indeed, the apparatus, methods, and systems described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the methods and systems described herein may be made without departing from the spirit of the disclosure. For example, while blocks are presented in a given arrangement, alternative embodiments may perform similar functionalities with different components and/or circuit topologies, and some blocks may be deleted, moved, added, subdivided, combined, and/or modified. At least one of these blocks may be implemented in a variety of different ways. The order of these blocks may also be changed. Any suitable combination of the elements and acts of the some embodiments described above can be combined to provide further embodiments. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the disclosure.

Claims

An apparatus comprising:

at least one processor; and

at least one memory comprising computer program code, the at least one memory and the computer program code being configured to, with the at least one processor, cause the apparatus to perform

receiving a configuration for determining a channel access priority or a channel access priority selection rule for an uplink transmission occasion based on at least a timing of the uplink transmission occasion,

determining a channel access priority for the uplink transmission occasion based on the configuration, and

transmitting a data unit using the uplink transmission occasion based on the determined channel access priority.
The apparatus of claim 1 wherein the timing of the uplink transmission occasion is related to at least one of an index of uplink transmission occasion associated with a configured grant, a slot index, a mini-slot index, an orthogonal frequency division multiplexing symbol index, a subframe index, a frame index, or at least one factor for deriving an occurring time of the at least one uplink transmission occasion.
The apparatus of claim 1 or 2, wherein the configuration for determining a channel access priority or a channel access priority selection rule comprises at least one of:

a configuration for determining a channel access priority from a plurality of channel access priorities configured for the apparatus, or

a configuration for determining a channel access priority selection rule from a plurality of channel access priority selection rules configured for the apparatus.
The apparatus of claim 3 wherein the plurality of channel access priority selection rules comprise a first channel access priority selection rule related to a content carried in the data unit, and a second channel access priority selection rule unrelated to the content carried in the data unit.
The apparatus of claim 3 wherein the first channel access priority selection rule is related to selecting a lower channel access priority associated with a content carried in the data unit, and the second channel access priority selection rule is related to selecting a higher channel access priority associated the content carried in the data unit.
The apparatus of any of claims 1 to 5 wherein the configuration indicates an uplink transmission occasion associated with a first channel access priority or a first channel access priority selection rule for the uplink transmission occasion, and the determining the channel access priority for the uplink transmission occasion based on the configuration comprises:

determining the first channel access priority or the first channel access priority selection rule for the uplink transmission occasion indicated by the configuration, and/or

determining a second channel access priority different from the first channel access priority or a second channel access priority selection rule different form the first channel access priority selection rule for at least one another uplink transmission occasion.
The apparatus of any of claims 1 to 5 wherein the configuration indicates a mapping between an uplink transmission occasion and a channel access priority or a channel access priority selection rule.
An apparatus comprising:

at least one processor; and

at least one memory comprising computer program code, the at least one memory and the computer program code being configured to, with the at least one processor, cause the apparatus to perform

transmitting a configuration for determining a channel access priority or a channel access priority selection rule for an uplink transmission occasion based on at least a timing of the uplink transmission occasion, and

receiving a data unit using the uplink transmission occasion.
The apparatus of claim 8 wherein the timing of the uplink transmission occasion is related to at least one of an index of uplink transmission occasion associated with a configured grant, a slot index, a mini-slot index, an orthogonal frequency division multiplexing symbol index, a subframe index, a frame index, or at least one factor for deriving an occurring time of the at least one uplink transmission occasion.
The apparatus of claim 8 or 9, wherein the configuration for determining a channel access priority or a channel access priority selection rule comprises at least one of:

a configuration for determining a channel access priority from a plurality of channel access priorities configured for a terminal device, or

a configuration for determining a channel access priority selection rule from a plurality of channel access priority selection rules configured for the terminal device.
The apparatus of claim 10 wherein the plurality of channel access priority selection rules comprise a first channel access priority selection rule related to a content carried in the data unit, and a second channel access priority selection rule unrelated to the content carried in the data unit.
The apparatus of claim 10 wherein the first channel access priority selection rule is related to selecting a lower channel access priority associated with a content carried in the data unit, and the second channel access priority selection rule is related to selecting a higher channel access priority associated the content carried in the data unit.
The apparatus of any of claims 8 to 12 wherein the configuration indicates an uplink transmission occasion associated with a first channel access priority or a first channel access priority selection rule.
The apparatus of any of claims 8 to 12 wherein the configuration indicates a mapping between an uplink transmission occasion and a channel access priority or a channel access priority selection rule.
A method comprising:

receiving, by a terminal device, a configuration for determining a channel access priority or a channel access priority selection rule for an uplink transmission occasion based on at least a timing of the uplink transmission occasion;

determining, by the terminal device, a channel access priority for the uplink transmission occasion based on the configuration; and

transmitting, by the terminal device, a data unit using the uplink transmission occasion based on the determined channel access priority.
The method of claim 15 wherein the timing of the uplink transmission occasion is related to at least one of an index of uplink transmission occasion associated with a configured grant, a slot index, a mini-slot index, an orthogonal frequency division multiplexing symbol index, a subframe index, a frame index, or at least one factor for deriving an occurring time of the at least one uplink transmission occasion.
The method of claim 15 or 16 wherein the configuration for determining a channel access priority or a channel access priority selection rule comprises at least one of:

a configuration for determining a channel access priority from a plurality of channel access priorities configured for the terminal device, or

a configuration for determining a channel access priority selection rule from a plurality of channel access priority selection rules configured for the terminal device.
The method of claim 17 wherein the plurality of channel access priority selection rules comprise a first channel access priority selection rule related to a content carried in the data unit, and a second channel access priority selection rule unrelated to the content carried in the data unit.
The method of claim 17 wherein the first channel access priority selection rule is related to selecting a lower channel access priority associated with a content carried in the data unit, and the second channel access priority selection rule is related to selecting a higher channel access priority associated with the content carried in the data unit.
The method of any of claims 15 to 19 wherein the configuration indicates an uplink transmission occasion associated with a first channel access priority or a first channel access priority selection rule for the uplink transmission occasion, and the determining the channel access priority for the uplink transmission occasion based on the configuration comprises:

determining the first channel access priority or the first channel access priority selection rule for the uplink transmission occasion indicated by the configuration, and/or

determining a second channel access priority different from the first channel access priority or a second channel access priority selection rule different from the first channel access priority selection rule for at least one another uplink transmission occasion.
The method of any of claims 15 to 19 wherein the configuration indicates a mapping between an uplink transmission occasion and a channel access priority or a channel access priority selection rule.
A method comprising:

transmitting, by a base station, a configuration for determining a channel access priority or a channel access priority selection rule for an uplink transmission occasion based on at least a timing of an uplink transmission occasion; and

receiving, by the base station, a data unit using the uplink transmission occasion.
The method of claim 22 wherein the timing of the uplink transmission occasion is related to at least one of an index of uplink transmission occasion associated with a configured grant, a slot index, a mini-slot index, an orthogonal frequency division multiplexing symbol index, a subframe index, a frame index, or at least one factor for deriving an occurring time of the at least one uplink transmission occasion of the at least one configured grant.
The method of claim 22 or 23 wherein the configuration for determining a channel access priority or a channel access priority selection rule comprises at least one of:

a configuration for determining a channel access priority from a plurality of channel access priorities configured for a terminal device, or

a configuration for determining a channel access priority selection rule from a plurality of channel access priority selection rules configured for the terminal device.
The method of claim 24 wherein the plurality of channel access priority selection rules comprises a first channel access priority selection rule related to a content carried in the data unit, and a second channel access priority selection rule unrelated to the content carried in the data unit.
An apparatus comprising:

means for receiving a configuration for determining a channel access priority or a channel access priority selection rule for an uplink transmission occasion based on at least a timing of the uplink transmission occasion;

means for determining a channel access priority for the uplink transmission occasion based on the configuration; and

means for transmitting a data unit using the uplink transmission occasion based on the determined channel access priority.
An apparatus comprising:

means for transmitting a configuration for determining a channel access priority or a channel access priority selection rule for an uplink transmission occasion based on at least a timing of the uplink transmission occasion; and

means for receiving a data unit using the uplink transmission occasion.
A computer readable medium comprising program instructions for causing an apparatus to perform a method of any of claims 15-25.