Patent Description:
The following abbreviations are herewith defined, at least some of which are referred to within the following description: Third Generation Partnership Project ("3GPP"), Fifth Generation Core Network ("5CG"), Fifth Generation System ("5GS"), Authentication, Authorization and Accounting ("AAA"), Access and Mobility Management Function ("AMF"), Access to Restricted Local Operator Services ("ARLOS"), Positive-Acknowledgment ("ACK"), Application Programming Interface ("API"), Authentication Center ("AuC"), Access Stratum ("AS"), Autonomous Uplink ("AUL"), AUL Downlink Feedback Information ("AUL-DFI"), Base Station ("BS"), Binary Phase Shift Keying ("BPSK"), Bandwidth Part ("BWP"), Clear Channel Assessment ("CCA"), Control Element ("CE"), Cyclic Prefix ("CP"), Cyclical Redundancy Check ("CRC"), Channel State Information ("CSI"), Common Search Space ("CSS"), Connection Mode ("CM", this is a NAS state in 5GS), Core Network ("CN"), Control Plane ("CP"), Data Radio Bearer ("DRB"), Discrete Fourier Transform Spread ("DFTS"), Downlink Control Information ("DCI"), Downlink ("DL"), Downlink Pilot Time Slot ("DwPTS"), Dual Connectivity ("DC"), Dual Registration mode ("DR mode"), Enhanced Clear Channel Assessment ("eCCA"), Enhanced Licensed Assisted Access ("eLAA"), Enhanced Mobile Broadband ("eMBB"), Evolved Node-B ("eNB"), Evolved Packet Core ("EPC"), Evolved Packet System ("EPS"), EPS Mobility Management ("EMM", this is a NAS state in EPS), Evolved UMTS Terrestrial Radio Access ("E-UTRA"), Evolved UMTS Terrestrial Radio Access Network ("E-UTRAN"), European Telecommunications Standards Institute ("ETSI"), Frame Based Equipment ("FBE"), Frequency Division Duplex ("FDD"), Frequency Division Multiple Access ("FDMA"), Frequency Division Orthogonal Cover Code ("FD-OCC"), General Packet Radio Service ("GPRS"), Generic Public Service Identifier ("GPSI"), Guard Period ("GP"), Global System for Mobile Communications ("GSM"), Globally Unique Temporary UE Identifier ("GUTI"), Hybrid Automatic Repeat Request ("HARQ"), Home Subscriber Server ("HSS"), Home Public Land Mobile Network ("HPLMN"), Information Element ("IE"), Internet-of Things ("IoT"), International Mobile Subscriber Identity ("IMSI"), Licensed Assisted Access ("LAA"), Load Based Equipment ("LBE"), Listen-Before-Talk ("LBT"), Long Term Evolution ("LTE"), Multiple Access ("MA"), Mobility Management ("MM"), Mobility Management Entity ("MME"), Modulation Coding Scheme ("MCS"), Machine Type Communication ("MTC"), Multiple Input Multiple Output ("MIMO"), Mobile Station International Subscriber Directory Number ("MSISDN"), Multi User Shared Access ("MUSA"), Narrowband ("NB"), Negative-Acknowledgment ("NACK") or ("NAK"), New Generation (<NUM>) Node-B ("gNB"), New Generation Radio Access Network ("NG-RAN", a RAN used for 5GS networks), New Radio ("NR", a <NUM> radio access technology; also referred to as "<NUM> NR"), Non-Access Stratum ("NAS"), Network Exposure Function ("NEF"), Non-Orthogonal Multiple Access ("NOMA"), Network Slice Selection Assistance Information ("NSSAI"), Operation and Maintenance System ("OAM"), Orthogonal Frequency Division Multiplexing ("OFDM"), Packet Data Unit ("PDU", used in connection with 'PDU Session'), Packet Switched ("PS", e.g., Packet Switched domain or Packet Switched service), Primary Cell ("PCell"), Physical Broadcast Channel ("PBCH"), Physical Downlink Control Channel ("PDCCH"), Physical Downlink Shared Channel ("PDSCH"), Pattern Division Multiple Access ("PDMA"), Physical Hybrid ARQ Indicator Channel ("PHICH"), Physical Random Access Channel ("PRACH"), Physical Resource Block ("PRB"), Physical Uplink Control Channel ("PUCCH"), Physical Uplink Shared Channel ("PUSCH"), Public Land Mobile Network ("PLMN"), Quality of Service ("QoS"), Quadrature Phase Shift Keying ("QPSK"), Radio Access Network ("RAN"), Radio Access Technology ("RAT"), Radio Resource Control ("RRC"), Random-Access Channel ("RACH"), Random Access Response ("RAR"), Radio Network Temporary Identifier ("RNTI"), Reference Signal ("RS"), Registration Area ("RA", similar to tacking area list used in LTE/EPC), Registration Management ("RM", refers to NAS layer procedures and states), Remaining Minimum System Information ("RMSI"), Resource Spread Multiple Access ("RSMA"), Round Trip Time ("RTT"), Receive ("RX"), Radio Link Control ("RLC"), Sparse Code Multiple Access ("SCMA"), Scheduling Request ("SR"), Single Carrier Frequency Division Multiple Access ("SC-FDMA"), Secondary Cell ("SCell"), Shared Channel ("SCH"), Session Management ("SM"), Session Management Function ("SMF"), Service Provider ("SP"), Signal-to-Interference-Plus-Noise Ratio ("SINR"), Single Network Slice Selection Assistance Information ("S-NSSAI"), Single Registration mode ("SR mode"), Sounding Reference Signal ("SRS"), System Information Block ("SIB"), Synchronization Signal ("SS"), Supplementary Uplink ("SUL"), Subscriber Identification Module ("SIM"), Tracking Area ("TA"), Transport Block ("TB"), Transport Block Size ("TBS"), Time-Division Duplex ("TDD"), Time Division Multiplex ("TDM"), Time Division Orthogonal Cover Code ("TD-OCC"), Transmission Time Interval ("TTI"), Transmit ("TX"), Unified Access Control ("UAC"), Unified Data Management ("UDM"), User Data Repository ("UDR"), Uplink Control Information ("UCI"), User Entity/Equipment (Mobile Terminal) ("UE"), UE Configuration Update ("UCU"), UE Route Selection Policy ("URSP"), Uplink ("UL"), User Plane ("UP"), Universal Mobile Telecommunications System ("UMTS"), UMTS Subscriber Identification Module ("USIM"), UMTS Terrestrial Radio Access ("UTRA"), UMTS Terrestrial Radio Access Network ("UTRAN"), Uplink Pilot Time Slot ("UpPTS"), Ultra-reliability and Low-latency Communications ("URLLC"), Visited Public Land Mobile Network ("VPLMN"), and Worldwide Interoperability for Microwave Access ("WiMAX"). As used herein, "HARQ-ACK" may represent collectively the Positive Acknowledge ("ACK") and the Negative Acknowledge ("NACK"). ACK means that a TB is correctly received while NACK (or NAK) means a TB is erroneously received.

For LTE eLAA, autonomous uplink (AUL) transmissions can be enabled through a combination of RRC signaling and an activation message conveyed by a DCI in a physical control channel. The RRC configuration includes subframes in which the UE is allowed to transmit autonomously, as well as eligible HARQ process IDs. The activation message includes the resource block assignment (RBA) and MCS, from which the UE is able to determine the transport block size for any AUL transmission.

When autonomous uplink (AUL) for unlicensed access in NR (NR-U) is used, the gNB may be unable to determine when an UL transmission/TB was initially generated due to potential LBT failures, even if the following (re)transmission of the same HARQ process are correctly decoded by the gNB. Such uncertainty may have in particular for PHR transmissions some negative impact, because the PHR content at the time of the transmission may not really reflect the status when it was generated.

R2-<NUM> describes methods relating to MAC CEs for AUL.

Code for carrying out operations for embodiments may be any number of lines and may be written in any combination of one or more programming languages including an object-oriented programming language such as Python, Ruby, Java, Smalltalk, C++, or the like, and conventional procedural programming languages, such as the "C" programming language, or the like, and/or machine languages such as assembly languages.

The code may also be loaded onto a computer, other programmable data processing apparatus, or other devices to cause a series of operational steps to be performed on the computer, other programmable apparatus or other devices to produce a computer implemented process such that the code which execute on the computer or other programmable apparatus provide processes for implementing the functions/acts specified in the flowchart diagrams and/or block diagrams.

Generally, the present disclosure describes systems, methods, and apparatus for reporting power headroom. In certain wireless communications networks, such as LTE eLAA, autonomous uplink ("AUL") transmissions are enabled through a combination of RRC signaling and an activation message conveyed by a DCI in a physical control channel. The RRC configuration includes subframes in which the UE is allowed to transmit autonomously, as well as eligible HARQ process IDs. The activation message includes the resource block assignment ("RBA") and a modulation and coding scheme ("MCS"), from which the UE is able to determine the transport block size for any AUL transmission.

It is possible to autonomously retransmit data pertaining to a transport block that has not been received correctly by the eNB. For this purpose, the UE monitors AUL downlink feedback information (e.g., "AUL-DFI"), transmitted by the eNB. The AUL-DFI includes HARQ-ACK information for the AUL-enabled HARQ process IDs. In case the UE detects a NACK message, it may try to autonomously access the channel for a retransmission of the same transport block in the corresponding HARQ process. As a safe-guard against errors, an AUL transmission includes at least the HARQ process ID and a new data indicator ("NDI") accompanying the PUSCH. In various embodiments, the AUL transmission includes uplink control information, AUL-UCI, which contains the HARQ process ID and NDI.

It is also possible for the eNB to transmit an uplink grant through a DCI that assigns uplink resources for a retransmission of the same transport block using the indicated HARQ process. It is further possible that the eNB transmits an uplink grant through a DCI that assigns uplink resources for a transmission of a new transport block using the indicated HARQ process. In other words, even though a HARQ process ID may be eligible for AUL transmissions, the eNB still has access to this process at any time through a scheduling grant (e.g., in DCI). Conventionally, if the UE detects a grant for an UL transmission for a subframe that is eligible for AUL (according to the RRC configuration), it will follow the received grant and will not perform an AUL transmission in that subframe.

When AUL for unlicensed access in NR (referred to as AUL for NR-U) is used, the gNB may be unable to determine when an UL transmission/TB was initially generated due to potential listen-before-talk ("LBT") failures, even if the following (re)transmission of the same HARQ process are correctly decoded by the gNB. For PHR transmissions, in particular, such uncertainty may have some negative impact, because the PHR content at the time of the transmission may not accurately reflect the status when it was generated. That could affect UL scheduling and link adaptation.

A more serious problem is that for the SUL case, e.g., UE is configured with two UL carriers for a serving cell, gNB needs to know when PHR was generated in order to know what PHR type is reported in the PHR MAC CE, e.g., type-<NUM> or type-<NUM> PHR. Currently, the UE is to report either type-<NUM> or type-<NUM> PH depending on whether UE determined a real or virtual PH for the two carriers.

If a UE is configured with two UL carriers for a serving cell and if the UE reports a UE capability "simultaneousTxSUL-NonSUL" for the serving cell, and if the UE determines that Type-<NUM> power headroom report for the serving cell is based on a reference PUSCH transmission and Type-<NUM> power headroom report for the serving cell is based on a reference SRS transmission, the UE provides the Type-<NUM> PHR.

If a UE is configured with two UL carriers for a serving cell and if the UE reports a UE capability "simultaneousTxSUL-NonSUL" for the serving cell, and if the UE determines that a power headroom for only one of the two UL carriers of the serving cell is based on an actual transmission, the UE provides a Type-<NUM> PHR when the actual transmission is a PUSCH transmission, or provides a Type-<NUM> PHR when the actual transmission is an SRS transmission.

In order to know at the gNB side whether the reported PHR value is a type-<NUM> or type-<NUM> PHR the gNB needs to know which grants are considered for the PH determination. Therefore, the gNB basically needs to know when the PHR was generated in order to understand whether the PHR MAC CE contains a PHR type-<NUM> or PHR type-<NUM> report. It should be noted that the PHR MAC CE format (multiple entry PHR MAC CE) doesn't explicitly indicate the PHR type, according to TS <NUM> v15.

This disclosure contains embodiments providing solutions for reporting power headroom. In a first solution, the UE signals timing information to the RAN node such as gNB, eNB or the like indicating whether the corresponding uplink transmission denotes the first transmission attempt or a second or later transmission attempt. In a second solution, the UE updates the content of a MAC CE contained in a TB for each transmission attempt. In a third solution, the UE always reports a predefined PHR type, e.g., type-<NUM> PHR, when the PHR MAC CE is transmitted on an unlicensed cell. In a fourth solution, a field in the PHR MAC CE indicates the type of reported PH value. In a fifth solution, the UE prioritizes transmission of a PHR MAC CE on a licensed cell over transmissions of a PHR MAC CE on an unlicensed cell. In a sixth solution, the UE reports a virtual PHR for a predefined PHR type, e.g., PHR type-<NUM>, for a serving cell configured with two UL carriers.

<FIG> depicts an embodiment of a wireless communication system <NUM> for accessing a denied network resource, according to various embodiments of the disclosure. In one embodiment, the wireless communication system <NUM> includes remote units <NUM>, base units <NUM>, and communication links <NUM>. Even though a specific number of remote units <NUM>, base units <NUM>, and communication links <NUM> are depicted in <FIG>, one of skill in the art will recognize that any number of remote units <NUM>, base units <NUM>, and communication links <NUM> may be included in the wireless communication system <NUM>.

In one implementation, the wireless communication system <NUM> is compliant with the NR system specified in the 3GPP specifications and/or the LTE system specified in 3GPP. More generally, however, the wireless communication system <NUM> may implement some other open or proprietary communication network, for example, WiMAX, among other networks.

In one embodiment, the remote units <NUM> may include computing devices, such as desktop computers, laptop computers, personal digital assistants ("PDAs"), tablet computers, smart phones, smart televisions (e.g., televisions connected to the Internet), smart appliances (e.g., appliances connected to the Internet), set-top boxes, game consoles, security systems (including security cameras), vehicle on-board computers, network devices (e.g., routers, switches, modems), or the like. The remote units <NUM> may communicate directly with one or more of the base units <NUM> via uplink ("UL") and downlink ("DL") communication signals. Furthermore, the UL and DL communication signals may be carried over the communication links <NUM>.

In some embodiments, a remote unit <NUM> may decide to establish a data connection (e.g., a PDU session) with an application server ("AS") <NUM> in the data network <NUM> via the mobile core network <NUM>. Here, the data path of a PDU session may be established over one of the multiple network slices supported by the mobile core network <NUM>. The specific network slice used by the PDU session may be determined by the S-NSSAI attribute of the PDU session. Here, the remote unit <NUM> may be provisioned with Network Slice Selection Policy ("NSSP") rules which it uses to determine how to route a requested PDU session.

The base units <NUM> may be distributed over a geographic region. In certain embodiments, a base unit <NUM> may also be referred to as a RAN node, an access terminal, a base, a base station, a Node-B, an eNB, a gNB, a Home Node-B, a relay node, a femtocell, an access point, a device, or by any other terminology used in the art. The base units <NUM> are generally part of an access network <NUM>, such as a radio access network ("RAN"), that may include one or more controllers communicably coupled to one or more corresponding base units <NUM>. These and other elements of the access network <NUM> are not illustrated but are well known generally by those having ordinary skill in the art. The base units <NUM> connect to the mobile core network <NUM> via the access network <NUM>. The access network <NUM> and mobile core network <NUM> may be collectively referred to herein as a "mobile network" or "mobile communication network.

The base units <NUM> may communicate directly with one or more of the remote units <NUM> via communication signals. Generally, the base units <NUM> transmit downlink ("DL") communication signals to serve the remote units <NUM> in the time, frequency, and/or spatial domain. Furthermore, the DL communication signals may be carried over the communication links <NUM>. The communication links <NUM> may be any suitable carrier in licensed or unlicensed radio spectrum. The communication links <NUM> facilitate communication between one or more of the remote units <NUM> and/or one or more of the base units <NUM>.

In one embodiment, the mobile core network <NUM> is a <NUM> core ("5GC"), which may be coupled to a data network <NUM>, like the Internet and private data networks, among other data networks. In some embodiments, the remote units <NUM> communicate with an application server ("AS") <NUM> (external to the mobile core network <NUM>) via a network connection with the mobile core network <NUM>. Each mobile core network <NUM> belongs to a single public land mobile network ("PLMN"). Other embodiments of the mobile core network <NUM> include an enhanced packet core ("EPC") or a Multi-Service Core as describe by the Broadband Forum ("BBF").

The mobile core network <NUM> includes several network functions ("NFs"). As depicted, the mobile core network <NUM> includes at least one user plane function ("UPF") <NUM>. The mobile core network <NUM> also includes multiple control plane functions including, but not limited to, an Access and Mobility Management Function ("AMF") <NUM> that serves the access network <NUM>, a Session Management Function ("SMF") <NUM>, a Network Exposure Function ("NEF") <NUM>, a Policy Control Function ("PCF") <NUM>, a Unified Data Management and Unified Data Repository function ("UDM/UDR") <NUM>. Control plane network functions provide services such as UE registration, UE connection management, UE mobility management, session management, and the like. In contrast, a UPF provides data transport services to the remote units <NUM>. In certain embodiments, the mobile core network <NUM> may also include, an Authentication Server Function ("AUSF"), a Network Repository Function ("NRF") (used by the various NFs to discover and communicate with each other over application programming interfaces ("APIs")), or other NFs defined for the 5GC.

The NEF <NUM> supports exposure of capabilities and events, secure provision of information from external application to 3GPP network, translation of internal/external information. The UDM/UDR <NUM> comprises a Unified Data Management ("UDM") and its internal component User Data Repository ("UDR"). The UDR holds subscription data including policy data. Specifically, the policy data stored by the UDM/UDR <NUM> includes the NSSP.

Although specific numbers and types of network functions are depicted in <FIG>, one of skill in the art will recognize that any number and type of network functions may be included in the mobile core network <NUM>. Moreover, where the mobile core network <NUM> is an EPC, the depicted network functions may be replaced with appropriate EPC entities, such as an MME, SGW, PGW, HSS, and the like. In certain embodiments, the mobile core network <NUM> may include an authentication, authorization, and accounting ("AAA") server.

In various embodiments, the mobile core network <NUM> supports different types of mobile data connections and different types of network slices, wherein each mobile data connection utilizes a specific network slice. Here, a "network slice" refers to a portion of the mobile core network <NUM> optimized for a certain traffic type or communication service. In certain embodiments, the various network slices may include separate instances of network functions, such as the SMF <NUM> and UPF <NUM>. In some embodiments, the different network slices may share some common network functions, such as the AMF <NUM>. The different network slices are not shown in <FIG> for ease of illustration, but their support is assumed.

The network slices are logical networks within the mobile core network <NUM>. In certain embodiments, the network slices are partitions of resources and/or services of the mobile core network <NUM>. Different network slices may be used to meet different service needs (e.g., latency, reliability, and capacity). Examples of different types of network slices include enhanced mobile broadband ("eMBB"), massive machine-type communication ("mMTC"), and ultra-reliability and low latency communications ("URLLC"). A mobile core network <NUM> may include multiple network slice instances of the same network slice type. Different network slice instance of the same type may be distinguished by a slice "tenant" (also known as "slice differentiator") associated with the instance.

Due to LBT failures the base unit <NUM> might not be aware of the time when the UE generated the TB transmitted on a configured grant resource and hence is not aware of when the PHR was calculated. There are basically two problems caused by this timing uncertainty. The first issue is that the base unit <NUM> doesn't know for which UL resource allocation, e.g. PRBs allocated in the slot for which PHR was calculated, the PH was calculated/reported and hence may draw some wrong conclusions for the future scheduling. Secondly the base unit <NUM> may not be aware of the reported PHR type - for cases when a serving cell is configured with two UL carriers - and may hence interpret the reported PH values incorrectly which in turn may lead to future scheduling decisions negatively impacting the performance.

To resolve the above noted problems with PHR reporting for an AUL transmission <NUM>, a remote unit <NUM> may perform one or more of: communicate timing information as part of AUL-UCI, update PH values for second/subsequent transmission attempts, always report using a predefined PHR type when transmitting a PHR MAC CE on an AUL PUSCH, and/or apply a policy rule for PHR type.

According to a first solution, the remote unit <NUM> signals timing information related to the calculation of the power headroom information to the base unit <NUM> (a RAN node, such as gNB, eNB or the like) indicating whether the corresponding uplink transmission corresponds to <NUM>) a first transmission attempt or <NUM>) a second or later transmission attempt. Because the remote unit <NUM> must first undergo a CCA (Clear Channel Assessment) procedure before a transmission can be made on the unlicensed spectrum, the remote unit <NUM> may be unable to transmit a generated TB immediately at the first transmission occasion/attempt, e.g., due to the CCA procedure not being successful for the first transmission attempt, but may only be able to transmit the generated TB at a later point of time when LBT (Listen Before Talk) is successful.

The timing information may be used by the base unit <NUM> (RAN node) for future scheduling/link adaption. In particular when receiving a PHR MAC CE, it is important to be aware at the base unit <NUM> when the PHR information was calculated in the remote unit <NUM>, in order to interpret the reported PH values correctly.

According to one implementation of the first solution, the timing information may be signaled by a one-bit field/flag. For example, when set to '<NUM>' the flag indicates that uplink transmission takes place at the first transmission occasion/attempt, e.g., CCA was successful. Similarly, the flag set to '<NUM>' indicates that the uplink transmission is done at the second or later transmission attempt, e.g., generated TB couldn't be transmitted immediately because CCA wasn't successful. In other embodiments, the flag values may be switched such that a value of '<NUM>' indicated a first transmission attempt and a value of '<NUM>' indicates a second or later transmission attempt.

According to another implementation of the first solution, the timing information may indicate the offset (e.g., in number of frames, slots, subframes, or symbols) to the first transmission attempt using multiple bits. In case CCA is successful for the first transmission attempt, e.g., generated TB is immediately transmitted on corresponding next available PUSCH occasion, the timing information would indicate a "zero" slot/symbol offset. Accordingly, when the transmission of the TB takes place <NUM> slots after the first transmission attempt, e.g., LBT failed before, the timing information will indicate a <NUM> slot offset. As an alternative, the timing information may indicate the number of transmission attempts respectively the number of LBT failures for the TB until CCA was successful, e.g., using multiple bits.

According to certain implementations of the first solution, the timing information is transmitted as part of uplink control information (UCI), which is transmitted independently from the PUSCH transmission (transport block). The UCI conveying the timing information is encoded separately from the PUSCH data. Hence, the base unit <NUM> receiver will decode the UCI separately form the PUSCH. In one implementation of the first embodiment the timing information is carried within the AUL-UCI.

<FIG> depicts one embodiment of an AUL-UCI <NUM>, according to embodiments of the disclosure. The AUL-UCI <NUM> contains a plurality of fields, including the AUL-RNTI <NUM>, the HARQ process number <NUM>, the redundancy version ("RV") <NUM>, a New Data Indicator ("NDI") <NUM>, the PUSCH starting symbol <NUM>, the PUSCH ending symbol <NUM>, and channel occupancy time ("COT") sharing indication <NUM>. Importantly, the AUL-UCI <NUM> contains a 'PH timing information' field <NUM>, indicating timing related to the calculation of the power headroom information. As depicted, the PH timing information <NUM> may be represented by three bits in the AUL-UCI. In one embodiment, the PH timing information <NUM> indicates the number of transmission attempts. In another embodiment, the PH timing information <NUM> indicates the offset to the first transmission attempt. The information carried within this field is used in the scheduler/gNB for future scheduling/link adaption. It basically provides the base unit <NUM> with the information when the TB was generated.

According to a second solution, the remote unit <NUM> updates the content of a MAC CE contained in a TB for each transmission attempt. For example, in case a generated TB was unable to be transmitted at a transmission (PUSCH) occasion due to LBT failure, the remote unit <NUM> will update the content of the MAC CEs carried within the TB for the next transmission attempt. Put another way, the MAC CEs in a TB are to always indicate the most up-to date values.

In particular, for a PHR MAC CE contained in a TB, the remote unit <NUM> may update the reported PH values for each transmission attempt such that the base unit <NUM> - when receiving a PHR MAC CE - is aware of when the reported PH values were calculated, e.g., the base unit <NUM> knows what control information (such as uplink grants and configured grants) were considered for the calculation of the reported PHR. The second solution also ensures that the base unit <NUM> is aware of what type of PHR is reported within the PHR MAC CE, e.g., whether type-<NUM> or type-<NUM> PHR is reported for a cell configured with two UL carriers (SUL and NUL).

Apart from the PHR MAC CE, also it may be beneficial for the scheduler to update the BSR MAC CE indicating the buffer status of the remote unit <NUM> for each transmission attempt. According to one implementation of the second embodiment only the values reported within a MAC CE, e.g., PHR MAC CE, are updated for each transmission attempt, but the PDU format of the MAC CE is not changed. Doing so ensures that the remote unit <NUM> doesn't need to run the logical channel prioritization (LCP) procedure again.

According to a third solution, the remote unit <NUM> always reports a predefined PHR type, e.g., type-<NUM> PHR, for a serving cell which is configured with two (uplink) carriers (e.g., SUL and NUL) and/or for cases when the PHR MAC CE is transmitted on an unlicensed serving cell. As mentioned above, according to the current defined UE behavior in standards, the remote unit <NUM> reports either a type-<NUM> or type-<NUM> PHR report for a serving cell configured with two carriers depending on whether an actual PUSCH or SRS transmission takes place on the carriers in the reporting slot. Therefore, the base unit <NUM> needs to know when the remote unit <NUM> determined the PHR types for the serving cells in order to know what information is included in the PHR MAC CE, e.g., PHR type-<NUM> or PHR type-<NUM>.

According to various implementations of the third solution, a new/special rule for PHR value determination (PHR type-<NUM> versus PHR type-<NUM>) may be used for cases when PHR MAC CE is transmitted on an unlicensed cell compared to cases where the PHR MAC CE is transmitted on a licensed cell. This new rule ensures that the gNB is always aware of which PHR type, e.g., type-<NUM> or type-<NUM> PHR, is signaled within a PHR MAC CE.

According to one implementation of the third solution the remote unit <NUM> always reports using a predefined PHR type, e.g., type-<NUM> PHR, for a serving cell which is configured with two carriers, e.g., SUL and NUL, and for cases when the PHR MAC CE is transmitted on an AUL PUSCH. For scheduled PUSCH transmission on an unlicensed cell, legacy UE reporting behavior with respect to PHR reporting is applied.

One implementation of the third solution maybe described using the following rule: If a UE (remote unit <NUM>) is configured with two UL carriers for a serving cell and if the UE reports a UE capability simultaneousTxSUL-NonSUL for the serving cell, and if a PHR is transmitted on an AUL-PUSCH, then the UE (remote unit <NUM>) provides a Type-<NUM> PHR for the serving cell.

According to a fourth solution, a field in the PHR MAC CE indicates the type of the reported PH value, e.g., whether PHR type-<NUM> or PHR type-<NUM>. According to one implementation of the fourth solution, at least one of the 'reserved' fields in the octet where PCMAX is signaled for a serving cell is used for indicating the PHR type. In one implementation one of the reserved fields 'R,' when set to '<NUM>', may indicate that the PH value is a type-<NUM> PH value. Accordingly, when set to '<NUM>' the corresponding reported PH value is a type-<NUM> PH value. In another implementation both 'R' fields may be used to indicate the PHR type (e.g., to distinguish between up to four different PHR types).

<FIG> depicts one embodiment of a MAC PDU format <NUM> for the PHR MAC CE, according to embodiments of the invention. The MAC PDU format <NUM> may be used to implement the fourth solution described herein. It should be noted that this shown option should be only understood as an example of an implementation. As depicted, the exemplary MAC PDU format for the PHR MAC CE contains a new field, denoted as 'T,' which indicates the PHR type. One (or both) of the 'R' fields in the octet including PCMAX is reused as the new "T" field.

According to a fifth solution, the remote unit <NUM> prioritizes transmission of a PHR MAC CE on a licensed cell over transmissions of a PHR MAC CE on an unlicensed cell. Here, for cases when there are PUSCH resources available for an initial transmission on a licensed cell as well as for an unlicensed cell, the remote unit <NUM> transmits a PHR MAC CE, e.g., PHR has been triggered before, on the PUSCH resources of the licensed cell. According to one implementation of the fifth solution, where the remote unit <NUM> is configured with at least one licensed cell and at least one unlicensed cell, then the remote unit <NUM> always transmits a PHR MAC CE on a licensed cell, e.g., PHR MAC CE are not allowed to be transmitted on an unlicensed cell. According to another implementation of the fifth solution, the remote unit <NUM> is not to transmit a PHR MAC CE on an AUL-PUSCH. Here, when performing the LCP procedure for an AUL transmission, the remote unit <NUM> is not to multiplex a PHR MAC CE in the transport block.

According to a sixth solution, a remote unit <NUM> (e.g., UE) configured with carrier aggregation reports a virtual PHR for a predefined PHR type, e.g., PHR type-<NUM>, for a serving cell configured with two UL carriers. Further, the remote unit <NUM> reports a virtual PHR for other activated serving cells (with configured uplink) for cases when <NUM>) the PHR MAC CE is transmitted on a configured grant, e.g., PUSCH resources allocated by a configured grant, on an unlicensed cell or <NUM>) when the PHR MAC CE is transmitted on a configured grant PUSCH resource and the MAC entity is configured with Ich-basedPrioritization. According to this implementation of the sixth solution, remote unit <NUM> reports for all activated serving cells (with configured uplink) a virtual PHR - for a serving cell configured with two UL carrier a virtual PHR for a predefined PHR type, e.g., PHR type-<NUM>.

According to one alternative implementation of the sixth solution, the remote unit <NUM> reports actual PHR for the serving cell on which the PHR MAC CE is transmitted and reports a virtual PHR for other activated serving cells (with configured uplink). Further, if a serving cell is configured with two UL carriers, then the remote unit <NUM> reports a virtual PHR for a predefined PHR type for cases when the PHR MAC CE is transmitted on a configured grant on an unlicensed cell or for cases when the PHR MAC CE is transmitted on a configured grant PUSCH resource and the MAC entity is configured with lch-basedPrioritization.

Reporting a predefined/fixed PHR type of a serving cell configured with two UL carriers solves the issue of the base unit <NUM> (e.g., gNB) not being aware of the reported PHR type. Reporting a virtual PHR solves the issue of the base unit <NUM> (e.g., gNB) not knowing for which UL resource allocation(s) the PH was calculated. It should be noted that the same problems may also occur for cases when a configured grant PUSCH transmission is pre-empted or deprioritized due to some higher priority UL transmission requiring an overlapping PUSCH resource. For example, the configured grant may be preempted by a later received dynamic UL grant scheduling an overlapping PUSCH resource. Therefore, according to the sixth solution, the remote unit <NUM> configured with carrier aggregation reports a virtual PHR for a predefined PHR type, e.g., PHR type-<NUM>, for a serving cell configured with two UL carriers and reports a virtual PHR for other activated serving cells (with configured uplink) for cases when the MAC entity is configured with Ich-basedPrioritization. The condition "configured with lch-basedPrioritization" refers to the case where the network (e.g., base unit <NUM>) configures the remote unit <NUM> to allow a (low) priority UL transmission to be deprioritized/preempted by some (later) high priority UL grant/transmissions, which is a new feature of the Industrial IOT WI. It is assumed that the prioritization mechanism feature is configured per UE for backward compatibility and separation from UEs not supporting this feature. This terminology may be changed later during further discussions in 3GPP.

According to another embodiment, a remote unit <NUM> not configured with carrier aggregation reports a virtual PHR for the serving cell for cases when the PHR MAC CE is transmitted on a configured grant, e.g., PUSCH resources allocated by a configured grant, and the serving cell is an unlicensed cell as well as for cases when the PHR MAC CE is transmitted on a configured grant PUSCH resource and the MAC entity is configured with Ich-basedPrioritization. According to one implementation of this embodiment UE reports a PCMAX,f,c value within the single-entry PHR MAC CE even for the case that virtual PHR is reported.

<FIG> depicts a user equipment apparatus <NUM> that may be used for PHR reporting, according to embodiments of the disclosure. In various embodiments, the user equipment apparatus <NUM> is used to implement one or more of the solutions described above. The user equipment apparatus <NUM> may be one embodiment of the remote unit <NUM>, described above. Furthermore, the user equipment apparatus <NUM> may include a processor <NUM>, a memory <NUM>, an input device <NUM>, an output device <NUM>, and a transceiver <NUM>. In some embodiments, the input device <NUM> and the output device <NUM> are combined into a single device, such as a touchscreen. In certain embodiments, the user equipment apparatus <NUM> may not include any input device <NUM> and/or output device <NUM>. In various embodiments, the user equipment apparatus <NUM> may include one or more of: the processor <NUM>, the memory <NUM>, and the transceiver <NUM>, and may not include the input device <NUM> and/or the output device <NUM>.

In various embodiments, the processor <NUM> identifies a transmission occasion for AUL transmission on an unlicensed serving cell and generates a PHR MAC CE. The transceiver <NUM> then transmits the PHR MAC CE with an AUL transmission to a RAN node in the mobile communication network. Here, transmitting the PHR MAC CE includes indicating timing information corresponding to the PHR. In some embodiments, the timing information provides information to the RAN node on the first transmission attempt of the PHR MAC CE. In some embodiments, the timing information includes a one-bit flag, wherein a first value of the one-bit flag indicates that the PHR MAC CE transmission corresponds to a first transmission attempt and a second value of the one-bit flag indicates that the PHR MAC CE transmission corresponds to a subsequent transmission attempt.

In some embodiments, the timing information includes an indication of a timing offset between the PHR MAC CE transmission and a first transmission attempt. In one embodiment, the timing offset indicates a number of slots elapsed since the first transmission attempt. In another embodiment, the timing offset indicates a number of symbols elapsed since the first transmission attempt. In some embodiments, the timing information includes an indication of a number of transmission attempts prior to the PHR transmission. In some embodiments, the timing information is transmitted as part of uplink control information and is encoded separately from the PHR.

In various embodiments, the processor <NUM> identifies a first transmission occasion for AUL transmission on an unlicensed serving cell. The processor <NUM> generates a PHR MAC CE including power headroom information for each activated serving cell configured with uplink. Here, the power headroom information for an activated serving cell is calculated for a predetermined PHR type in response to the serving cell being configured with two UL carriers. The transceiver <NUM> that then transmits the PHR MAC CE in an AUL transmission to a RAN node in the mobile communication network. In some embodiments, the processor <NUM> prioritizes transmitting the PHR MAC CE on a licensed cell over transmitting the PHR on the unlicensed serving cell.

In various embodiments, the processor <NUM> identifies a first transmission occasion on a configured uplink grant resource. The processor <NUM> generates a PHR MAC CE including power headroom information for each activated serving cell. Here, the power headroom information is calculated for a predetermined PHR type in response to a serving cell being configured with two UL carriers. The transceiver <NUM> then transmits the PHR MAC CE in a configured grant transmission to a RAN node in the mobile communication network.

In some embodiments, generating the PHR MAC CE includes reporting a virtual power headroom for each activated serving cell in response to the PHR MAC CE being transmitted on a configured uplink grant and further in response to a MAC entity of the user equipment apparatus <NUM> being configured to deprioritize a lower priority uplink transmission in favor of a higher priority uplink transmission. In such embodiments, preparing the PHR MAC CE includes reporting a virtual PHR for a predefined PHR type in response to a serving cell being configured with two UL carriers.

In some embodiments, that user equipment apparatus <NUM> is configured for carrier aggregation using multiple activated serving cells, wherein preparing the PHR MAC CE includes reporting an actual PHR for the serving cell on which the PHR MAC CE is to be transmitted and reporting virtual PHR for one or more other activated serving cells.

In some embodiments, the memory <NUM> stores data related to power headroom reporting. For example, the memory <NUM> may store PH values, AUL data, AUL configuration information, timing offsets, and the like. In certain embodiments, the memory <NUM> also stores program code and related data, such as an operating system or other controller algorithms operating on the remote unit <NUM>.

As discussed above, the transceiver <NUM> communicates with one or more network functions of a mobile communication network via one or more access networks. The transceiver <NUM> operates under the control of the processor <NUM> to transmit messages, data, and other signals and also to receive messages, data, and other signals. For example, the processor <NUM> may selectively activate the transceiver <NUM> (or portions thereof) at particular times in order to send and receive messages.

The transceiver <NUM> may include one or more transmitters <NUM> and one or more receivers <NUM>. Although only one transmitter <NUM> and one receiver <NUM> are illustrated, the user equipment apparatus <NUM> may have any suitable number of transmitters <NUM> and receivers <NUM>. Further, the transmitter(s) <NUM> and the receiver(s) <NUM> may be any suitable type of transmitters and receivers. Additionally, the transceiver <NUM> may support at least one network interface <NUM>. Here, the at least one network interface <NUM> facilitates communication with a RAN node, such as an eNB or gNB, for example using the "Uu" interface. Additionally, the at least one network interface <NUM> may include an interface used for communications with one or more network functions in the mobile core network, such as a UPF, an AMF, and/or a SMF.

In one embodiment, the transceiver <NUM> includes a first transmitter/receiver pair used to communicate with a mobile communication network over licensed radio spectrum and a second transmitter/receiver pair used to communicate with a mobile communication network over unlicensed radio spectrum.

In various embodiments, one or more transmitters <NUM> and/or one or more receivers <NUM> may be implemented and/or integrated into a single hardware component, such as a multi-transceiver chip, a system-on-a-chip, an application-specific integrated circuit ("ASIC"), or other type of hardware component. In certain embodiments, one or more transmitters <NUM> and/or one or more receivers <NUM> may be implemented and/or integrated into a multi-chip module. In some embodiments, other components such as the network interface <NUM> or other hardware components/circuits may be integrated with any number of transmitters <NUM> and/or receivers <NUM> into a single chip. In such embodiment, the transmitters <NUM> and receivers <NUM> may be logically configured as a transceiver <NUM> that uses one more common control signals or as modular transmitters <NUM> and receivers <NUM> implemented in the same hardware chip or in a multi-chip module.

<FIG> depicts a base station apparatus <NUM> that may be used for reporting power headroom, according to embodiments of the disclosure. The base station apparatus <NUM> may be one embodiment of the remote unit <NUM> or UE, described above. Furthermore, the base station apparatus <NUM> may include a processor <NUM>, a memory <NUM>, an input device <NUM>, an output device <NUM>, and a transceiver <NUM>. In some embodiments, the input device <NUM> and the output device <NUM> are combined into a single device, such as a touchscreen. In certain embodiments, the base station apparatus <NUM> may not include any input device <NUM> and/or output device <NUM>. In various embodiments, the base station apparatus <NUM> may include one or more of: the processor <NUM>, the memory <NUM>, and the transceiver <NUM>, and may not include the input device <NUM> and/or the output device <NUM>.

For example, the processor <NUM> may be a microcontroller, a microprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, or similar programmable controller.

In various embodiments, the base station apparatus <NUM> receives (e.g., via the transceiver <NUM>) a PHR from a served UE. Additionally, the base station apparatus <NUM> may receive timing information relating to the PHR, as described herein. Using the timing information, the processor <NUM> interprets the reported power headroom values.

In various embodiments, the processor <NUM> identifies a number of uplink carriers for a serving cell of the UE. The processor <NUM> may use the configuration of uplink carriers to interpret the reported power headroom values, for example inferring PHR type (e.g., type-<NUM> or type-<NUM>) from the uplink carrier configuration and/or inferring actual or virtual PHR from the uplink carrier configuration.

In some embodiments, the memory <NUM> stores data related to reporting power headroom. For example, the memory <NUM> may store PH timing information, UL carrier configurations, PHR values, and the like. In certain embodiments, the memory <NUM> also stores program code and related data, such as an operating system or other controller algorithms operating on the remote unit <NUM>.

As another, non-limiting, example, the output device <NUM> may include a wearable display separate from, but communicatively coupled to, the rest of the base station apparatus <NUM>, such as a smart watch, smart glasses, a heads-up display, or the like.

The transceiver <NUM> includes at least transmitter <NUM> and at least one receiver <NUM>. One or more transmitters <NUM> may be used to communicate with the UE, as described herein. Similarly, one or more receivers <NUM> may be used to communicate with other network functions in the PLMN, as described herein. Although only one transmitter <NUM> and one receiver <NUM> are illustrated, the base station apparatus <NUM> may have any suitable number of transmitters <NUM> and receivers <NUM>. Further, the transmitter(s) <NUM> and the receiver(s) <NUM> may be any suitable type of transmitters and receivers.

<FIG> depicts one embodiment of a method <NUM> for reporting power headroom, according to embodiments of the disclosure. In various embodiments, the method <NUM> is performed by the remote unit <NUM> and/or the user equipment apparatus <NUM>, described above. In some embodiments, the method <NUM> is performed by a processor, such as a microcontroller, a microprocessor, a central processing unit (CPU), a graphics processing unit (GPU), an auxiliary processing unit, a FPGA, or the like.

The method <NUM> begins and identifies <NUM> a transmission occasion for AUL transmission on an unlicensed serving cell. The method <NUM> includes generating <NUM> a PHR MAC CE. The method <NUM> includes transmitting <NUM> the PHR MAC CE with an AUL transmission to a RAN node in the mobile communication network. Here, transmitting the PHR MAC CE includes indicating timing information corresponding to the PHR. The method <NUM> ends.

<FIG> depicts one embodiment of a method <NUM> for reporting power headroom, according to embodiments of the disclosure. In various embodiments, the method <NUM> is performed by a UE, such as the remote unit <NUM> and/or the user equipment apparatus <NUM>, described above. In some embodiments, the method <NUM> is performed by a processor, such as a microcontroller, a microprocessor, a central processing unit (CPU), a graphics processing unit (GPU), an auxiliary processing unit, a FPGA, or the like.

The method <NUM> begins and identifies <NUM> a first transmission occasion for AUL transmission on an unlicensed serving cell. The method <NUM> includes generating <NUM> a PHR MAC CE including power headroom information for each activated serving cell configured with uplink. Here, the power headroom information for an activated serving cell is calculated for a predetermined PHR type in response to the serving cell being configured with two UL carriers. The method <NUM> includes transmitting <NUM> the PHR MAC CE in an AUL transmission to a RAN node in the mobile communication network. The method <NUM> ends.

The method <NUM> begins and identifies <NUM> a first transmission occasion on a configured uplink grant resource. The method <NUM> includes generating <NUM> a PHR MAC CE including power headroom information for each activated serving cell.

The method <NUM> includes transmitting <NUM> the PHR MAC CE to a RAN node in the mobile communication network. Here, the power headroom information is calculated for a predetermined PHR type in response to a serving cell being configured with two UL carriers. The method <NUM> ends.

Disclosed herein is a first apparatus for reporting power headroom, according to embodiments of the disclosure. The first apparatus may be implemented by a UE, such as the remote unit <NUM> and/or the user equipment apparatus <NUM>. The first apparatus includes a processor that identifies a transmission occasion for AUL transmission on an unlicensed serving cell and generates a PHR MAC CE. The first apparatus includes a transceiver that transmits the PHR MAC CE with an AUL transmission to a RAN node in the mobile communication network, wherein transmitting the PHR MAC CE includes indicating timing information corresponding to the PHR.

In some embodiments, the timing information provides information to the RAN node on the first transmission attempt of the PHR MAC CE. In some embodiments, the timing information includes a one-bit flag, wherein a first value of the one-bit flag indicates that the PHR MAC CE transmission corresponds to a first transmission attempt and a second value of the one-bit flag indicates that the PHR MAC CE transmission corresponds to a subsequent transmission attempt.

In some embodiments, the timing information includes an indication of a timing offset between the PHR MAC CE transmission and a first transmission attempt. In one embodiment, the timing offset indicates a number of slots elapsed since the first transmission attempt. In another embodiment, the timing offset indicates a number of symbols elapsed since the first transmission attempt.

In some embodiments, the timing information includes an indication of a number of transmission attempts prior to the PHR transmission. In some embodiments, the timing information is transmitted as part of uplink control information and is encoded separately from the PHR.

Disclosed herein is a first method for reporting power headroom, according to embodiments of the disclosure. The first method may be performed by a UE, such as the remote unit <NUM> and/or the user equipment apparatus <NUM>. The first method includes identifying a transmission occasion for AUL transmission on an unlicensed serving cell. The first method includes generating a PHR MAC CE and transmitting the PHR MAC CE with an AUL transmission to a RAN node in the mobile communication network, wherein transmitting the PHR MAC CE includes indicating timing information corresponding to the PHR.

In some embodiments of the first method, the timing information provides information to the RAN node on the first transmission attempt of the PHR MAC CE. In some embodiments of the first method, the timing information includes a one-bit flag, wherein a first value of the one-bit flag indicates that the PHR MAC CE transmission corresponds to a first transmission attempt and a second value of the one-bit flag indicates that the PHR MAC CE transmission corresponds to a subsequent transmission attempt.

In some embodiments of the first method, the timing information includes an indication of a timing offset between the PHR MAC CE transmission and a first transmission attempt. In one embodiment, the timing offset indicates a number of slots elapsed since the first transmission attempt. In another embodiment, the timing offset indicates a number of symbols elapsed since the first transmission attempt.

In some embodiments of the first method, the timing information includes an indication of a number of transmission attempts prior to the PHR transmission. In some embodiments of the first method, the timing information is transmitted as part of uplink control information and is encoded separately from the PHR.

Disclosed herein is a second apparatus for reporting power headroom, according to embodiments of the disclosure. The second apparatus may be implemented by a UE configured for carrier aggregation using multiple serving cells for power headroom reporting in a mobile communication network, such as the remote unit <NUM> and/or the user equipment apparatus <NUM>. The second apparatus includes a processor that identifies a first transmission occasion for AUL transmission on an unlicensed serving cell. The processor generates a PHR MAC CE including power headroom information for each activated serving cell configured with uplink, wherein the power headroom information for an activated serving cell is calculated for a predetermined PHR type in response to the serving cell being configured with two UL carriers. The second apparatus includes a transceiver that transmits the PHR MAC CE in an AUL transmission to a RAN node in the mobile communication network.

In some embodiments, the processor prioritizes transmitting the PHR MAC CE on a licensed cell over transmitting the PHR on the unlicensed serving cell.

Disclosed herein is a second method for reporting power headroom, according to embodiments of the disclosure. The second method may be performed by a UE configured for carrier aggregation using multiple serving cells for power headroom reporting in a mobile communication network, such as the remote unit <NUM> and/or the user equipment apparatus <NUM>. The second method includes identifying a first transmission occasion for AUL transmission on an unlicensed serving cell and generating a PHR MAC CE including power headroom information for each activated serving cell configured with uplink, wherein the power headroom information for an activated serving cell is calculated for a predetermined PHR type in response to the serving cell being configured with two UL carriers. The second method includes transmitting the PHR MAC CE in an AUL transmission to a RAN node in the mobile communication network.

In some embodiments, the second method further includes prioritizing transmission of the PHR MAC CE on a licensed cell over transmitting the PHR on the unlicensed serving cell.

Disclosed herein is a third apparatus for reporting power headroom, according to embodiments of the disclosure. The third apparatus may be implemented by a UE configured with carrier aggregation for power headroom reporting in a mobile communication network, such as the remote unit <NUM> and/or the user equipment apparatus <NUM>. The third apparatus includes a processor that identifies a first transmission occasion on a configured uplink grant resource and generates a PHR MAC CE including power headroom information for each activated serving cell, wherein the power headroom information is calculated for a predetermined PHR type in response to a serving cell being configured with two UL carriers. The third apparatus includes a transceiver that transmits the PHR MAC CE in a configured grant transmission to a RAN node in the mobile communication network.

In some embodiments, generating the PHR MAC CE includes reporting a virtual power headroom for each activated serving cell in response to the PHR MAC CE being transmitted on a configured uplink grant and further in response to a MAC entity of the apparatus being configured to deprioritize a lower priority uplink transmission in favor of a higher priority uplink transmission. In such embodiments, preparing the PHR MAC CE includes reporting a virtual PHR for a predefined PHR type in response to a serving cell being configured with two UL carriers.

In some embodiments, that apparatus is configured for carrier aggregation using multiple activated serving cells, wherein preparing the PHR MAC CE includes reporting an actual PHR for the serving cell on which the PHR MAC CE is to be transmitted and reporting virtual PHR for one or more other activated serving cells.

Disclosed herein is a third method for reporting power headroom, according to embodiments of the disclosure. The third method may be performed by a UE configured with carrier aggregation for power headroom reporting in a mobile communication network, such as the remote unit <NUM> and/or the user equipment apparatus <NUM>. The third method includes identifying a first transmission occasion on a configured uplink grant resource. The third method includes generating a PHR MAC CE including power headroom information for each activated serving cell and transmitting the PHR MAC CE to a RAN node in the mobile communication network. Here, the power headroom information is calculated for a predetermined PHR type in response to a serving cell being configured with two UL carriers.

In some embodiments of the third method, generating the PHR MAC CE includes reporting a virtual power headroom for each activated serving cell in response to the PHR MAC CE being transmitted on a configured uplink grant and further in response to a MAC entity of the UE being configured to deprioritize a lower priority uplink transmission in favor of a higher priority uplink transmission. In such embodiments, preparing the PHR MAC CE includes reporting a virtual PHR for a predefined PHR type in response to a serving cell being configured with two UL carriers.

Claim 1:
A method (<NUM>) of a user equipment, UE, for power headroom reporting in a mobile communication network, the method comprising:
identifying (<NUM>) a transmission occasion for autonomous uplink, AUL, transmission on an unlicensed serving cell;
generating (<NUM>) a power headroom report, PHR, Medium Access Control, MAC, Control Element, CE; and
transmitting (<NUM>) the PHR MAC CE with an AUL transmission to a radio access network, RAN, node in the mobile communication network,
wherein transmitting the PHR MAC CE comprises indicating timing information corresponding to power headroom information, wherein the timing information indicates a time when the power headroom information was generated.