Patent Publication Number: US-2022232479-A1

Title: Uplink power and resource allocation enhancement for user devices

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This patent application claims priority to and the benefit of European Patent Application No. 21382048.3 filed on Jan. 21, 2021 and entitled “Uplink Power and Resource Allocation Enhancement for User Devices,” the entire disclosure of which is hereby incorporated by reference. 
     FIELD OF THE DISCLOSURE 
     This document relates to wireless communications and, more particularly, to systems, methods, and techniques of allocating uplink resources in wireless communications systems. 
     BACKGROUND 
     The background description provided within this document is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure. 
     User equipment (UE) manufacturers (which are also referred to as Original Equipment Manufacturers or OEMs) must comply with jurisdictional regulatory authorities such as the Federal Communications Commission (FCC) in the United States or Council of the European Union to limit radio frequency (RF) energy exposed to the human body. Generally, regulatory authorities specify the maximum amount of energy that is absorbed per unit mass by a human body exposed to an electromagnetic field, and commonly refer to this parameter as Specific Absorption Rate (SAR). SAR depends on the maximum transmission power level (MTPL) of a UE, sub-carrier signal modulation, channel bandwidth, resource block allocation, the relative position of the device to the human body and, for time division duplex (TDD) transmissions, the Uplink (UL)/Downlink (DL) duty cycle (also referred to interchangeably herein as the “UL duty cycle”). Specifically, for TDD transmissions, larger numbers of radio resources configured for UL transmissions result in larger SAR values. 
     For UE SAR certification purposes, regulatory authorities typically mandate determining the SAR limits of a UE based on the supported configuration that generates the most transmitted power, e.g., a maximum transmitted power level (MTPL) of the UE. That is, the SAR limits are based on the lowest Power Class the UE supports and the highest UL/DL duty cycle provided by the 3GPP standard to which the UE conforms. 
     5G NR (New Radio)-compatible UEs may support 5G NR only in a standalone mode (SA), or may support 5G NR along with Long Term Evolution (LTE) in a dual-connectivity (DC) mode (e.g., by utilizing multiple uplinks). LTE provides for a fixed number UL/DL radio frame configurations. For example, 3GPP TS 36.211 V12.4.0 (2014 December), Table 4.2-2 defines seven UL/DL radio frame configurations. The specific LTE UL/DL configuration having the largest UL/DL duty cycle among the seven defined LTE UL/DL radio frame configurations typically results in a maximum LTE UL/DL duty cycle of about 65%. 
     Compared to LTE, however, 3GPP TS 38.213 V15.2.0 (2018 July) allows for greater flexibility of radio frame configurations for 5G NR, among which the largest UL/DL duty cycle is about 90-100% for TDD transmissions. As such, for SAR certification purposes, using the most restrictive possible UL/DL configuration of the UE (e.g., the “worst case scenario,” which is typically based on a lowest power class supported by the UE and a lowest maximum LTE UL duty cycle) when establishing the maximum transmission power limits (MTPL) of the UE for SAR compliance results in extreme scenarios, e.g., 90-100% NR UL/DL duty cycle. The UE stores the maximum transmission power limits to which the UE is subject for SAR compliance, e.g., on a per frequency band basis. 
     Additionally, per the 3GPP Release 16 standard, during a Radio Resource Control (RRC) establishment procedure, the base station signals a specific UL/DL duty cycle with which the UE must comply. Today, in field deployments of commercial mobile broadband networks and systems, maximally-restrictive radio frame configurations are not widely utilized. This is because operators prioritize downlink capabilities over uplink capabilities, e.g., to support video streaming and other downlink data delivery intensive applications. For example, in present field deployments, the base station typically signals the UE to use a UL/DL duty cycle for the connection of around 25-30%, with which the UE must comply. Further, the base station does not update this UL/DL duty cycle in real-time. 
     As such, the operation of 5G NR-compatible UEs, which are theoretically capable of high UL/DL duty cycles not commonly utilized in practice (if at all), introduces unnecessarily large transmit power cut-backs, which in turn degrades the uplink RF performance of UEs and may underutilize available link resources. Indeed, basing the actual operations of 5G NR UEs on the most restrictive possible UL/DL configuration rather than on actually supported and/or utilized configurations may result in a reduction of SAR-compliant uplink transmit power and a reduction of cell site coverage. Accordingly, such a sub-optimally operated UE, while being SAR-compliant, needlessly decreases the efficiency of the overall system, as well as negatively impacts the user&#39;s experience. 
     SUMMARY 
     The techniques described in this document determine the maximum UL/DL duty cycle (e.g., the maximum TDD UL/DL duty cycle) a UE can use for a particular connection with a base station in view of the frequency bands supported by the UE and information received from the base station. Generally, the determined maximum UL/DL duty cycle of the UE used during the UE&#39;s connection with the base station is less than the maximum UL/DL duty cycle corresponding to the maximum transmit power level (MTPL) of the UE. That is, the determined maximum UL/DL duty cycle of the UE used during the UE&#39;s connection with the base station is typically less than the most restrictive possible UL/DL configuration of the UE which was used for certifying the UE for SAR compliance. These techniques also allow a UE to notify the base station of the maximum UL/DL duty cycle the UE has determined for the connection upon registering with the network, so that the base station may configure UL and DL resources accordingly and, in some situations, dynamically. In this manner, the system can provide better uplink performance and more comprehensive cell site coverage and system efficiencies while maintaining the UE&#39;s SAR compliance. 
     During a procedure for setting a radio connection for communicating with a base station, a UE receives, from the base station, a request for the capabilities of the UE, e.g., via a UECapabilityEnquiry message. Based on the content of the request for the capabilities of the UE, the UE determines a maximum uplink duty cycle for the connection with the base station. The UE then signals, to the base station, an indication of this maximum uplink duty cycle, e.g., via an Information Element (IE) of a UECapabilityInformation message. In many situations, the maximum UL duty cycle for the connection is less than a maximum UL duty cycle of the UE utilized to certify the UE for compliance with Specific Absorption Requirements (SAR) of a jurisdiction corresponding to the connection. 
     The UE may determine the maximum uplink duty cycle for the connection based on the content of the request for UE capabilities and a set of frequency bands supported by the UE, where the set of frequency bands supported by the UE may be different than a set of frequency bands supported by the base station and/or by the system in which the base station is included. In embodiments, the content of the request for UE capabilities indicates a set of frequency bands requested by the base station for possible use while communicating with the UE (e.g., a set of “requested” frequency bands). In these embodiments, the maximum UL duty cycle that the UE signals to the base station for the connection is a maximum UL duty cycle of a particular UE-supported frequency band having a lowest maximum UL duty cycle among one or more UE-supported frequency bands included in the set of requested frequency bands. In embodiments in which the content of the request for UE capabilities sent by the base station to the UE excludes an indication of any requested frequency band, the maximum UL duty cycle of the connection (which the UE signals to the base station) is a maximum UL duty cycle of a particular UE-supported frequency band having a lowest maximum UL duty cycle among an entirety of the set of UE-supported frequency bands. In these embodiments, the UE may store an indication of the maximum UL duty cycle in a global parameter, for example. 
     When radio connection configurations between the UE and the base station change, the UE may update the maximum UL duty cycle for the connection with the base station to correspond to the updated configuration. The UE may signal, to the base station, an indication of the updated maximum UL duty cycle for the updated connection so that the base station may re-configure UL and DL resources accordingly. 
     Advantageously, the techniques discussed within this disclosure may be utilized and, indeed, customized for any and all power classes supported by the UE. 
     In an example embodiment, a method in a user equipment device (UE) for managing resource allocation includes, during a procedure to establish a connection between the UE and a base station, receiving, by processing hardware of the UE from the base station, a request for capabilities of the UE; determining, by the processing hardware and based on a content of the request, a maximum uplink (UL) duty cycle of the UE for the connection; and providing, by the processing hardware to the base station, an indication of the maximum UL duty cycle. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  depicts an example wireless communication system in which devices such as base stations and User Equipments (UEs) communicate data, where the system supports the management of resource allocation in accordance with at least some of the principles and techniques disclosed in this document. 
         FIG. 2  depicts an example message flow between a base station and a UE to manage resource allocation in accordance with at least some of the principles and techniques disclosed in this document. 
         FIG. 3  depicts a flow diagram of an example method for managing resource allocation in accordance with at least some of the principles and techniques disclosed in this document. 
         FIG. 4  depicts an example message flow between a base station and a UE to manage resource allocation in accordance with at least some of the principles and techniques disclosed in this document. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  depicts an example wireless communication system  100  in which devices such as base stations and User Equipments (UEs) communicate data, and that supports the systems, methods, and techniques of this document. The wireless communication system  100  includes one or more base stations  102 , which  FIG. 1  depicts by a single base station representation and this document refers to by using the singular tense for ease of discussion (and not for limitation purposes). The base station  102  may support one or more Radio Access Networks (RANs) of one or more Radio Access Technologies (RATs), such as NR (New Radio), LTE (Long Term Evolution), and/or one or more RATs which may respectively utilize a sub-6 GHz frequency band, a mmWave frequency band, a Terahertz frequency band, a frequency band at or corresponding to 1900 MHz, a frequency band at or corresponding to 850 MHz, an unlicensed frequency band, etc. The base station  102  communicatively connects to one or more types of core networks (CNs)  105  (e.g., SGC, EPC, etc.), which in turn communicatively connect to the Internet and/or any number of other networks  108 , which may include one or more private and/or public networks  108 . Similar to its depiction of the base station  102 ,  FIG. 1  depicts the one or more core networks  105  by using a singular representation, and this document refers to the one or more CNs  105  by using the singular tense for ease of discussion (and not for limitation purposes). 
     A User Equipment (UE)  110 , which can be any suitable device capable of wireless communications using one or more types of RATs, can communicatively connect (reference  111 ) with the wireless communication system  100  via the base station  102 . The UE  110  includes processing hardware  112  that can include one or more processors (e.g., CPUs)  115  and one or more non-transitory, tangible, computer-readable memories  118  storing computer-executable instructions that the one or more processors  115  read and/or execute. Particularly, the instructions include maximum uplink (UL) duty cycle determination instructions  120  (which, for ease of reading, are also referred to within this document as the “max UL duty cycle determiner  120 ”) for determining a maximum UL duty cycle for the UE  110  to utilize for the connection  111  and for informing the base station  102  of such, in accordance with one or more of the methods, principles, and techniques disclosed in this document. The memories  118  can also store other instructions  122 , in embodiments. In an example implementation of the UE  110 , the one or more processors  115  execute the computer-executable instructions  120 ,  122  to perform any one or more of the portions of the described methods and/or techniques. In some implementations, the one or more processors  115  execute the computer-executable instructions  120 ,  122  to operate in conjunction with firmware and/or other portions of the processing hardware  112  to perform any one or more of the portions of the described methods and/or techniques. 
     Additionally, the memories  118  of the UE  110  can store data that is utilized to perform any one or more of the portions of the methods and/or techniques described within this document. In particular, as illustrated in  FIG. 1 , the memories  118  store power data  125 . Power data  125  may include data indicative of one or more maximum transmission power levels (MTPLs) of the UE  110 . Typically, the MTPLs of the UE  110  are pre-determined, pre-configured into the power data  125 , and indicate corresponding MPTL values so that the UE  110  complies with Specific Absorption Rate (SAR) requirements given the UE&#39;s various, fixed physical properties (such as the model of the UE  110 , different numbers and types of antennas, etc.) as well as the possible variable properties of the UE  110  during operations (such as frequency band, sub-carrier signal modulation, channel bandwidth, resource block allocation, the relative position of the UE  110  to a human user, power classes supported by the UE, RATs supported by the UE, and, for time division duplex (TDD) transmissions, the Uplink (UL)/Downlink (DL) duty cycle (“UL duty cycle”). The UE  110  utilizes the MTPL information included in the power data  125  to determine a maximum transmit UL duty cycle (which this document interchangeably refers to as a “maximum UL duty cycle,” a “max UL duty cycle,” a “maximum TDD UL duty cycle,” a “maximum TDD UL/DL duty cycle,” or a “maximum UL/DL duty cycle”) for a specific connection  111  with the base station  102  so that the UE  110  is able to comply with SAR requirements during operations while utilizing the connection  111 . In general, the maximum uplink duty cycle represents the maximum percentage of a given time period during which a UE can transmit on an uplink without a predetermined Specific Absorption Rate being exceeded. The Specific Absorption Rate may be predetermined by a regulatory authority, for example. 
     In an embodiment, the power data  125  may include a respective MTPL for each frequency band supported by the UE  110 , where at least some of the frequency band-specific MTPLs may differ. In some embodiments, the power data  125  may include respective MTPLs for at least some of the UE-supported frequency bands in different jurisdictions, where one or more of the jurisdiction-specific MTPLs may differ for a given frequency band. For example, the power data  125  may define a first MTPL for a specific UE-supported frequency band in a first jurisdiction, and may define a different, second MTPL for the specific UE-supported frequency band in a different, second jurisdiction. In some embodiments, the power data  125  additionally distinguishes MTPLs based on power class, so that different power classes supported by the UE  110  may be associated with different MTPLs (e.g., for a same frequency band and/or for a same jurisdiction). 
     Of course, the memories  118  may store other data  128  in addition to the power data  125 . The UE  110  may utilize the stored data  125 ,  128  while performing one or more of the portions of the described methods and/or techniques. Further, as shown in  FIG. 1 , the example processing hardware  112  includes one or more Radio Resource Control (RRC) controllers  130  which are used to communicate Radio Frequency (RF) signals with the base station  102  via radios in accordance with one or more different types of RATs supported by the UE  110 . 
     Generally speaking, when the UE  110  and the base station  102  undergo connection procedures to set up a communicative connection  111  via which data may be sent and received, the base station  102  requests the UE  110  to send an indication of the capabilities of the UE  110 , e.g., via a UECapabilityEnquiry message. The UE  110  responds to the request, and returns information indicative of the UE&#39;s capabilities, including an indication of a maximum UL duty cycle of the UE  110  for the connection  111 , e.g., so the UE  110  is able to maintain SAR compliance during the connection  111 . For example, the UE  110  may signal its maximum UL duty cycle to the base station  102  via an Information Element (IE) of a UECapabilityInformation message. 
     As previously discussed, in response to a base station&#39;s query for UE capabilities, a currently-known UE merely signals, to the base station, its most restrictive maximum UL duty cycle. Typically, the most restrictive maximum UL duty cycle corresponds to the configuration utilized to certify the UE for SAR compliance, e.g., a configuration of a lowest power class supported by the UE and a maximum LTE UL duty cycle (e.g., a maximum supported or available LTE UL duty cycle, which may be 100% of the UE supports 100%). However, a currently-known UE does not determine its maximum UL duty cycle based on particular conditions of operations particular to the UE and/or to the base station to which the UE is connecting, and a currently-known UE does not have a mechanism for reporting locally-stored maximum UL/DL cycles to the base station to which the UE is connecting. As such, a currently-known UE may operate at a maximum UL/DL cycle determined based on a worst case scenario instead of allowing for operations up to a maximum UL/DL cycle customized for a particular connection of the UE with a particular base station while still maintaining SAR compliance. Further, operating a currently-known UE at its most restrictive maximum UL/DL duty cycle may introduce unnecessarily large power cut-backs and resulting degradations in uplink RF performances of the UE, as well as sub-optimal cell site coverage of the wireless communication system. Indeed, such sub-optimally operated, currently-known UEs, while being SAR-compliant, needlessly decrease the efficiency of the overall system, as well as negatively impact the user&#39;s experience. 
     On the other hand,  FIG. 2  depicts an example message flow  200  between a base station  202  and a UE  210  to manage resource allocations in a manner which is specific or customized for the connection between the UE  210  and the base station  202 , in accordance with at least some of the principles and techniques disclosed in this document. Generally speaking, the base station  202  (e.g., one or more radios at the base station  202 ) is included in a RAN via which the UE  210  connects to a CN of the wireless communication system  100 . For ease of discussion in this document, though, the RAN and CN associated with the base station  202  are not separately depicted in  FIG. 2 . Embodiments of the system  100  may implement embodiments of the example message flow  200 , in some implementations. For example, the base station  202  may be the base station  102  of the system  100 , and the UE  210  may be the UE  110  of the system  100 . However, the message flow  200  may be implemented in other wireless communication systems other than the system  100 , by other UEs other than the UE  110 , and/or by other base stations other than the base station  102 . For ease of illustration, though, and not for limitation purposes, this document discusses the message flow  200  with simultaneous reference to the system  100  depicted in  FIG. 1 . 
     During procedures for communicatively connecting the base station  202  and the UE  210 , the base station  202  sends a request for the capabilities of the UE (reference  212 ). For example, the UE capabilities request  212  may be a UECapabilityEnquiry message, or some other suitable UE capabilities request message. In an embodiment, the UE capabilities request  212  indicates a set of requested frequency bands, which generally is a set of frequency bands which the base station  202  requests the UE  210  to utilize in communicating with the base station  202 . 
     Upon receiving the UE capabilities request  212 , the UE  210  determines  215  a maximum UL duty cycle for its connection with the base station  202  (e.g., connection  111  of  FIG. 1 ) based on a content of the UE capabilities request  212 . That is, instead of the UE  210  merely using the most restrictive UL duty cycle indicated by its stored power data  125 , the UE  210  assesses the content of the UE capabilities request  212  and utilizes the contents of the request  212  to determine the maximum UL duty cycle which may be used for the connection  111  between the UE  210  and the base station  202 . Said another way, the UE  210  customizes the maximum possible UL duty cycle for its connection  111  with the base station  202  based on the content of the base station&#39;s request  212 . For example, the UE  210  may determine the maximum UL duty cycle for the connection  111  based on a set of requested frequency bands which the base station  202  indicates in the UE capabilities request  212 , and/or based on other characteristics of and/or information included in the content of the UE capabilities request  212 . Typically, the maximum UL duty cycle which the UE  210  determines  215  for the connection is less than the most restrictive maximum UL duty cycle of the UE  210 , thus allowing for greater uplink data throughput via the connection  111  while maintaining the UE&#39;s SAR compliance. This document provides a more detailed description of the UE  210  determining  215  the maximum UL duty cycle for the connection  111  based on the UE Capabilities request  212  elsewhere in other sections. 
     In the message flow  200  of  FIG. 2 , upon determining  215  the maximum UL duty cycle for its connection  111  with the base station  202 , the UE  210  indicates the determined maximum UL duty cycle to the base station  202  (along with other information) in a response  218  to the request  212 . For example, the UE  110  may indicate its determined, maximum UL duty cycle for the connection  111  to the base station  102  via an Information Element (IE) of a UECapabilityInformation message, or via some other suitable field or response message. Upon reception of the response  218 , the base station  202  configures  220  the UL/DL configuration for the connection  111  with the UE  210  based on the maximum UL duty cycle indicated by the UE  210  in the response  218 . 
       FIG. 3  depicts a flow diagram of an example method  300  for managing resource allocation, e.g., for managing the allocation of resources utilized for communications between a UE and a base station, in accordance with at least some of the principles and techniques disclosed within this document. A UE may perform at least a portion of the method  300 , for example. In an example implementation, the UE is the UE  110  of  FIG. 1  or the UE  210  of FIG.  210 , and the UE  110 ,  210  performs at least a portion of the method  300 , e.g., by executing the maximum UL duty cycle determination instructions  120  and optionally other instructions  122 . In some embodiments, at least a portion of the method  300  may be executed in conjunction with at least portions of one or more other methods and/or message flows described within this document. For example, at least a portion of the method  300  may be executed in conjunction with at least a portion of the message flow  200  of  FIG. 2  and/or at least a portion of the message flow  400  of  FIG. 4 . In some embodiments, the method  300  includes one or more alternate and/or additional actions other than those shown in  FIG. 3 . For ease of discussion, and not for limitation purposes, though, this document discusses the method  300  with simultaneous reference to the wireless communication system  100  of  FIG. 1  and the message flow  200  of  FIG. 2 , although the method  300  may execute in wireless communication systems other than the system  100  and/or in conjunction with messages flows other than the message flow  200 . 
     As shown in  FIG. 3 , the method  300  includes, during a procedure to establish a connection between a UE and a base station, receiving  302 , at the UE from the base station, a request for capabilities of the UE. As previously discussed, the UE may be the UE  110 , the UE  210 , or another suitable UE, for example. As such, in an example implementation, the processing hardware  112  of the UE  110  may receive the request for UE capabilities. The base station which sends the request for UE capabilities to the UE may be the base station  102 , the base station  202 , or another suitable base station of a wireless communication system, and/or the received request for UE capabilities may be the request  212  of  FIG. 2 , for example. The received request for UE capabilities  302  may be included in a UECapabilityEnquiry message or in some other suitable UE capabilities request message. In some scenarios, the received UE capabilities request includes an indication of a set of requested frequency bands, e.g., a set of frequency bands which the base station requests the UE to utilize for the connection. 
     Further, the method  300  may include, during the procedure to establish the connection between the UE and the base station, determining  305 , by the processing hardware of the UE, a maximum uplink (UL) duty cycle of the UE for the connection based on a content of the received UE capabilities request. Determining  305  the maximum UL duty cycle for the connection based on the content of the received UE capabilities request may correspond to reference  215  of the message flow  200  of  FIG. 2 , for example. In an embodiment, determining  305  the maximum UL duty of the UE for the connection may be based on both the content of the request for UE capabilities and a set of frequency bands supported by the UE. The UE may store an indication of the set of frequency bands which it supports, e.g., in the power data  125  and/or in the other data  128  memories, for example, and may access and/or retrieve the stored indication to determine  305  the maximum UL duty cycle of the UE. 
     To illustrate, in a first example scenario pertaining to the block  305 , the content of the received UE capabilities request indicates a set of frequency bands requested by the base station to use for the connection with the UE (e.g., a set of requested frequency bands). The UE may determine or identify a set of candidate frequency bands based on the set of frequency bands requested by the base station and the set of frequency bands supported by the UE. For example, the UE may determine one or more frequency bands, each of which is both (i) included in the set of requested frequency bands indicated by the base station and (ii) included in the set of UE-supported frequency bands indicated in the power data  125  and/or in the other data  128  memories. In an embodiment, determining the set of candidate frequency bands includes identifying all frequency bands which meet both (i) and (ii); that is, the determined set of candidate frequency bands is an intersection of the set of base station requested frequency bands and the set of UE-supported frequency bands. 
     Additionally in this first example scenario, for each candidate frequency band, the UE may retrieve an indication of a respective maximum UL duty cycle value, for example, by accessing the stored power data  125 . As previously discussed, the power data  125  may store an indication of a respective MTPL for each frequency band supported by the UE. The indications of the respective MTPLs of the UE-supported frequency bands may be represented by respective maximum transmit power levels (e.g., in units of decibels per milliwatt (dBm), or in other suitable units), by respective maximum UL duty cycles (e.g., at least because a MTPL generated by the UE corresponds to the percentage of time and/or symbols a UE is transmitting on the UL compared to the percentage of time and/or symbols the UE is receiving on the downlink), or by any other suitable representation. At any rate, irrespective of the representation format of the respective MTPLs of the candidate frequency bands within the power data  125 , the UE may compare the respective indications of the respective MTPLs of the candidate frequency bands to thereby determine a lowest UL duty cycle among the candidate frequency bands, and the UE may determine this lowest UL duty cycle among the candidate frequency bands to be the maximum UL duty cycle for the connection between the UE and the base station. As such, in this first example scenario, the UE determines the maximum UL duty cycle for the connection based only on the candidate frequency bands which may be used to support the connection, and not based on any frequency bands which will not be used for the connection. As such, the MTPL of a frequency band that will not be used for the connection does not have any influence on the maximum UL duty cycle of the connection. Further, as the UE determines the lowest UL duty cycle among the candidate frequency bands to be the maximum UL duty cycle for the connection of the UE with the base station, the maximum UL duty cycle of the connection corresponds to the most conservative or most limiting UL duty cycle among the candidate frequency bands, thereby ensuring the UE&#39;s SAR compliance irrespective of which candidate frequency band is utilized for the connection with the base station during operations. Advantageously, in this first example scenario, the maximum UL duty cycle for the connection is typically less than the most restrictive maximum UL duty cycle (e.g., the maximum UL duty cycle corresponding to the lowest MTPL indicated in the power data  125 , which typically corresponds to the lowest power class supported by the UE and a maximum available or supported LTE UL duty cycle of the UE, which may be 100% if the UE supports 100%), and consequently allows a greater downlink data delivery throughput over that allowed by the most restrictive maximum UL duty cycle. Further, unlike the most restrictive maximum UL duty cycle which currently-known UEs utilize for all power classes supported by the UE, the maximum UL duty cycle for the connection may be determined or customized  305  specifically for any power class supported by the UE (e.g., as indicated in the power data  125 ). 
     With further regard to determining  305  the maximum uplink (UL) duty cycle of the UE for the connection based on the content of the received UE capabilities request, in a second example scenario pertaining to the block  305 , the content of the received UE capabilities request excludes any indication of frequency bands requested by the base station to be utilized for the connection between the UE and the base station. Accordingly, in this second example scenario, the UE may determine the UE-supported frequency band which has a lowest UL duty cycle among an entirety of the set of UE-supported frequency bands. For example, the UE may retrieve a respective indication of a respective MTPL for each UE-supported frequency band, e.g., by accessing the stored power data  125  in a manner similar to that discussed above for the first example scenario. In this second example scenario, the UE may compare the respective indications of the respective MTPLs of the entire set of UE-supported frequency bands to thereby identify a lowest UL duty cycle among the entire set of UE-supported frequency bands, and the UE may determine this lowest UL duty cycle to be the maximum UL duty cycle for the connection between the UE and the base station. As the UE determines the lowest UL duty cycle among the entirety of the set of UE-supported frequency bands to be the maximum UL duty cycle for the connection, the maximum UL duty cycle of the connection corresponds to the most conservative or most limiting UL duty cycle among the set of UE-supported frequency bands, thereby ensuring the UE&#39;s SAR compliance irrespective of which UE-supported frequency band is utilized for the connection with the base station during operations. 
     In an embodiment, the UE performs the comparison of respective MTPLs of the set of UE-supported frequency bands a priori and not in-line with a specific connection procedure with a base station. For example, as the UE stores indications of all frequency bands which the UE supports, e.g., in the power data  125  and/or in the other data  128 , the UE may determine, a priori, the maximum UL duty cycle for any connection where a base station does not request any frequency band during connection setup procedures with the UE. The UE may store an indication of this maximum UL duty cycle corresponding to the entire set of UE-supported frequency bands in a global parameter, e.g., as part of the power data  125  or in the other data  128 . As such, during operations, when a base station does not indicate any requested frequency bands during a connection set up procedure (e.g., within a request for UE capabilities), the UE may simply access the global parameter to determine the maximum UL duty cycle for the corresponding connection. In some implementations, rather than the UE performing the comparison of MTPLs for the set of UE-supported frequency bands and populating the global parameter, an off-line process may determine the value of the global parameter and populate the global parameter along with configuring the UE with the power data  125  or the data  128 , e.g., prior to the UE being activated for operations. As such, the UE may be pre-configured with both the power data  125  and an indication of the maximum UL duty cycle to utilize when a base station does not indicate any requested frequency bands. As utilized herein, the parameter is a “global” parameter as the value of the parameter may apply to any and all of the frequency bands supported by the UE. That is, the maximum UL duty cycle indicated by the value stored in the global parameter is applicable to each frequency band supported by the UE. 
     Additionally with regard to the block  305  of the method  300 , in an embodiment, determining  305  the maximum UL duty cycle of the UE for the connection may be further based on a number of operational UL transceivers of the UE. The UE may include one or more transceivers corresponding to one or more RATs and frequency bands, e.g., 4G LTE, 5G NR, Wi-Fi, satellite, mmWave, sub-6 GHz, etc., at least one of which may be operational at any given time. When only one of the transceivers of the UE is operational or active, determining the maximum UL duty cycle for the connection may proceed in a manner such as described above, e.g., for UE capabilities request messages with and without indications of requested frequency bands. That is, when the UE has only a single operational or active transceiver, the maximum UL duty cycle for the connection between the UE and the base station may correspond to the maximum UL power budget for the UE as a whole. 
     On the other hand, when more than one transceiver of the UE is operational or active, the maximum UL duty cycle of the UE for the connection, e.g., the maximum UL power budget for the UE as a whole, may be allocated among the multiple operational/active transceivers. Multiple transceivers may be simultaneously operational or active at the UE, for example, when the UE utilizes radio technologies such as UL Carrier Aggregation or Dual Connectivity. In these situations, the UE may first determine an overall maximum UL duty cycle for the connection with the base station. In other words, the UE may first determine a UL power budget for the UE as a whole, e.g., in a manner such as described above for UE capabilities messages with and/or without indications of requested frequency bands. Subsequently, UE may allocate equal or non-equal portions of the UE&#39;s overall UL power budget among the multiple operational transceivers to thereby determine the respective maximum UL duty cycle of each transceiver for the connection. In an embodiment, the UE may decrease the respective maximum UL duty cycles of the transceivers based on a total number of operational/active transceivers at the UE, for example, in a proportional manner so that each operational/active transceiver is allocated an equal portion of the UE&#39;s overall UL power budget. In another embodiment, the UE may decrease the respective maximum UL duty cycles of the multiple, operational/active transceivers based on respective bandwidths supported by the transceivers which are active/operational. For example, an active transceiver which supports a wider bandwidth may be allocated a smaller portion of the UE&#39;s overall UL power budget relative to the portion of the UE&#39;s overall UL power budget allocated to an active transceiver which supports a narrower bandwidth, e.g., so that the relative sizes of the non-equal allocated proportions of the UE&#39;s overall UL power budget proportionally correspond to the relative sizes of the transceivers&#39; respective bandwidths. In yet another embodiment, the UE may decrease the respective maximum UL duty cycles of the multiple, operational/active transceivers in a manner that is not proportional. For example, the UE may decrease a first active transceiver&#39;s duty cycle from 80% to 70% and decrease a second active transceiver&#39;s duty cycle from 80% to 20% even though both transceivers support a same bandwidth. Of course, the UE may additionally or alternatively utilize other types of scaling or other modifications to allocate or determine the respective maximum UL duty cycles of multiple active/operational transceivers with respect to the connection with the base station and optionally one or more additional base stations. Additionally, if the number of operational/active transceivers changes, the UE may adjust the respective portions of the UE&#39;s overall UL power budget for each of the remaining operational/active transceivers. 
     Still, during the procedure to establish the connection between the UE and the base station, the method  300  may include providing or signaling  308 , by the processing hardware to the base station, an indication of the determined maximum UL duty cycle. For example, the UE may provide or signal  308  the indication of the maximum UL duty cycle to the base station in a response to the request of the base station, such as in an IE of a message that reports the capabilities of the UE to the base station, e.g., the response message  218  of  FIG. 2 . The response message may be, for example, a UECapabilityInformation message, or some other suitable response message. 
     In some embodiments, the method  300  further includes updating the maximum UL duty cycle of the UE for the connection with the base station when the carrier configuration changes, for example, due to an addition or a removal of one or more carrier components, e.g., as related to Carrier Aggregation or Dual Connectivity (not shown in  FIG. 3 ). For example, the UE may reallocate equal or non-equal portions of the overall UL power budget of the UE among the carrier components of the changed configuration. In an embodiment, the UE may proportionally increase or decrease the respective maximum UL duty cycles of the carrier components based on a total number of carrier components of the changed carrier configuration, so that each carrier component is re-allocated an equal portion of the UE&#39;s overall UL power budget. In another embodiment, the UE may proportionally increase or decrease the respective maximum UL duty cycles of the carrier components based on the respective bandwidths of the carrier components of the changed carrier configuration. For example, a carrier component which supports a wider bandwidth may be allocated a smaller portion of the UE&#39;s overall UL power budget relative to the size of the portion of the UE&#39;s overall UL power budget allocated to a carrier component which supports a narrower bandwidth, e.g., so that the relative sizes of the non-equal, re-allocated portions of the UE&#39;s overall UL power budget proportionally correspond to the relative sizes of the carrier components&#39; respective bandwidths. Of course, the UE may additionally or alternatively utilize other types of scaling or other modifications to re-allocate or determine the respective maximum UL duty cycles of the carrier components of the changed carrier configuration. At any rate, the UE may provide an indication of the updated, respective maximum UL duty cycle (e.g., of a corresponding carrier component) corresponding to the connection to the base station. For instance, the UE may transmit, to the base station, an indication that its capabilities have been updated (e.g., via a Tracking Area Update (TAU) message). In response, the base station transmits a request for the updated UE capabilities, and the response of the UE to the UE capabilities request includes an indication of the updated maximum UL duty cycle. 
     To illustrate,  FIG. 4  depicts an example message flow  400  between a base station  402  and a UE  410  to manage resource allocation, in accordance with at least some of the principles and techniques disclosed in this document. The message flow  400  may be implemented in conjunction with embodiments of the system  100  of  FIG. 1 , embodiments of the message flow  200  of  FIG. 2 , and/or embodiments of the method  300  of  FIG. 3 , if desired. For example, the base station  402  may be the base station  102  of  FIG. 1  or the base station  202  of  FIG. 2 , and/or the UE  410  may be the UE  110  of  FIG. 1  or the UE  210  of  FIG. 2 . However, the message flow  400  may be implemented in other wireless communication systems other than the system  100 , by other UEs other than the UEs  110 ,  210 , and/or by other base stations other than the base stations  102 ,  202 . For ease of illustration, though, and not for limitation purposes, this document discusses the message flow  400  with simultaneous reference to the system  100  depicted in  FIG. 1  and the method  300  of  FIG. 3 . 
     In  FIG. 4 , the base station  402  (e.g., one or more radios at the base station  402 ) is included in a RAN via which the UE  410  connects to a CN of the wireless communication system  100 . For ease of discussion in this document, though, the RAN and CN associated with the base station  410  are not separately depicted in  FIG. 4 .  FIG. 4  depicts two components of the UE  410 : the interface  412  of the UE  410  to, for example, the Radio Interface Layer (RIL) and the protocol layers of the Non-Access Stratum (NAS), and the maximum UL duty determiner  415 , which may be, for example, the maximum UL duty determiner  120  of  FIG. 1 . 
     In the scenario  400  depicted in  FIG. 4 , the radio connection between the base station  402  and the UE  410  has already been established, e.g., via message flow similar to message flow  200  of  FIG. 2 , and/or via a method similar to the method  300 , for example. Further, in  FIG. 4 , a change in the configuration of the carrier component(s) utilized between the base station  402  and UE  410  occurs. For example, UL Carrier Aggregation (CA) may be added to the configuration, or UL CA may be removed. Accordingly, the base station  402  notifies the UE of the change to the configuration of the carrier component(s) corresponding to the connection (reference  418 ), e.g., via an RRC Connection Reconfiguration message or other suitable message. In an embodiment, the reconfiguration message  418  includes an indication of the changed carrier component configuration. The interface  412  of the UE  410  receives the reconfiguration message  418 , and returns an acknowledgement of a receipt of the changed configuration to the base station  402  (reference  420 ), e.g., via an RCC Connection Reconfiguration Complete message, or other suitable message. Additionally, the interface  412  notifies the maximum UL duty determiner  415  of the change(s) to the carrier components corresponding to the connection between the UE  410  and the base station  402  (reference  422 ). Based on the changed carrier components  422 , the maximum UL duty determiner  415 ,  120  determines a respective updated maximum UL duty cycle for each carrier component of the changed configuration (reference  425 ), e.g., in a manner such as described above with respect to the method  300 . For example, the respective updated maximum UL duty cycle(s) may be updated based on a total number of carrier components included in the changed configuration, based on respective bandwidths of the carrier components included in the changed configuration, or in some other manner. The maximum UL duty determiner  415  informs the interface  412  of the UE  410  of the updated maximum UL duty cycle(s) (reference  428 ), and the interface  412  stores the updated maximum UL duty cycle(s) (reference  430 ). 
     Additionally, the interface  412  of the UE  410  notifies the base station  402  of the updated maximum UL duty cycle(s) (reference  432 ). For example, the UE  410  may transmit a Tracking Area Update (TAU) to the base station  410 , where the TAU indicates that the capabilities of the UE have been updated, and in response, the base station  410  may transmit a request for UE capabilities (reference  435 ) to thereby obtain indications of the updated UE capabilities (reference  438 ), including an indication of the update maximum UL duty cycle(s). Based on the updated maximum UL duty cycle(s), the base station  402  may re-configure  440  the UL/DL for the connection between the base station  402  and the UE  410 . 
     The following additional considerations apply to the foregoing discussion. 
     A user device or User Equipment (UE) in which the techniques of this document can be implemented (e.g., the UE  110 ,  210 ,  410 ) can be any suitable device capable of wireless communications such as a smartphone, a tablet computer, a laptop computer, a mobile gaming console, a point-of-sale (POS) terminal, a health monitoring device, a drone, a camera, a media-streaming dongle or another personal media device, a wearable device such as a smartwatch, a wireless hotspot, a femtocell, or a broadband router. Further, the user device in some cases may be embedded in an electronic system such as the head unit of a vehicle or an advanced driver assistance system (ADAS). Still further, the user device can operate as an internet-of-things (IoT) device or a mobile-internet device (MID). Depending on the type, the user device can include one or more general-purpose processors, a computer-readable memory, a user interface, one or more network interfaces, one or more sensors, etc. 
     Certain embodiments are described in this document as including logic or a number of components or modules. Modules may can be software modules (e.g., code stored on non-transitory machine-readable medium) or hardware modules. A hardware module is a tangible unit capable of performing certain operations and may be configured or arranged in a certain manner. A hardware module can include dedicated circuitry or logic that is permanently configured (e.g., as a special-purpose processor, such as a field programmable gate array (FPGA) or an application-specific integrated circuit (ASIC)) to perform certain operations. A hardware module may also include programmable logic or circuitry (e.g., as encompassed within a general-purpose processor or other programmable processor) that is temporarily configured by software to perform certain operations. The decision to implement a hardware module in dedicated and permanently configured circuitry, or in temporarily configured circuitry (e.g., configured by software) may be driven by cost and time considerations. 
     When implemented in software, the techniques can be provided as part of the operating system, a library used by multiple applications, a particular software application, etc. The software can be executed by one or more general-purpose processors or one or more special-purpose processors. 
     Upon reading this document, those of skill in the art will appreciate still additional alternative structural and functional designs for enhancing the handling of user equipment in a radio resource control inactive state through the principles disclosed in this document. Thus, while this document illustrates and describes particular embodiments and applications, the disclosed embodiments are not limited to the precise construction and components disclosed. Various modifications, changes and variations, which will be apparent to those of ordinary skill in the art, may be made in the disclosed arrangement, operation and details of the method, and apparatus without departing from the spirit and scope defined in the appended claims. 
     Further, although the foregoing text sets forth a detailed description of numerous different embodiments, it should be understood that the scope of the patent is defined by the words of the claims set forth at the end of this patent. The detailed description is to be construed as exemplary only and does not describe every possible embodiment because describing every possible embodiment would be impractical, if not impossible. Numerous alternative embodiments could be implemented, using either current technology or technology developed after the filing date of this patent, which would still fall within the scope of the claims and all equivalents thereof. By way of example, and not limitation, the disclosure herein contemplates at least the following aspects or examples: 
     Example 1. A method in a user equipment device (UE) for managing resource allocation, the method comprising, during a procedure to establish a connection between the UE and a base station: receiving, by processing hardware of the UE from the base station, a request for capabilities of the UE; determining, by the processing hardware and based on a content of the request, a maximum uplink (UL) duty cycle of the UE for the connection; and providing, by the processing hardware to the base station, an indication of the maximum UL duty cycle for the connection. 
     Example 2. The method of Example 1, wherein providing the indication of the maximum UL duty cycle includes: including the indication in an Information Element (IE) of a message that reports capabilities of the UE. 
     Example 3. The method of any one of Example 1 or Example 2, wherein determining the maximum UL duty cycle for the connection includes: determining the maximum UL duty cycle further based on a set of frequency bands supported by the UE, each frequency band of the set of frequency bands associated with a respective maximum UL duty cycle. 
     Example 4. The method of Example 3, further comprising: retrieving, by the processing hardware from a memory of the UE, an indication of at least one maximum UL duty cycle associated with the set of frequency bands. 
     Example 5. The method of any one of Examples 3 or 4, wherein: the content of the request indicates a set of requested frequency bands; and determining the maximum UL duty cycle based on the set of UE-supported frequency bands includes: 
     identifying, by the processing hardware, a set of candidate frequency bands that are both supported by the UE and included in the set of requested frequency bands; retrieving a set of indications of maximum UL duty cycles corresponding to the set of candidate frequency bands; and selecting, based on the set of indications of maximum UL duty cycles, a lowest maximum UL duty cycle as the maximum UL duty cycle for the connection. 
     Example 6. The method of Example 5, wherein identifying the one or more candidate frequency bands includes identifying each UE-supported frequency band included in the set of requested frequency bands. 
     Example 7. The method of any one of Examples 3-4, wherein determining the maximum UL duty cycle for the connection includes: determining that the content of the request does not specify any requested frequency bands; determining a frequency band having a lowest maximum UL duty cycle among the set of frequency bands supported by the UE; and selecting the duty cycle of the determined frequency band as the maximum UL duty cycle of the UE for the connection. 
     Example 8. The method of Example 7, wherein determining the frequency band having the lowest maximum UL duty cycle among the set of frequency bands supported by the UE includes accessing, by the processing hardware, a global parameter stored in a memory of the UE. 
     Example 9. The method of any one of Examples 1-8, wherein the maximum UL duty cycle of the UE for the connection is less than a UL duty cycle of the UE corresponding to a maximum transmission power level (MTPL) of the UE. 
     Example 10. The method of Example 9, wherein the UL duty cycle of the UE corresponding to the MTPL of the UE corresponds to a lowest power class supported by the UE and a configuration of the UE that has a maximum available UL duty cycle. 
     Example 11. The method of any one of Examples 1-10, further comprising storing, in a memory of the UE, power data indicative of a respective maximum transmission power level (MTPL) for each frequency band supported by the UE; and wherein determining the maximum UL duty cycle of the UE for the connection is further based on the power data. 
     Example 12. The method of Example 11, wherein storing the power data indicative of the MTPLs for the UE-supported frequency bands includes storing an indication of a respective MTPL for each jurisdiction in a plurality of jurisdictions for which the UE is configured. 
     Example 13. The method of any one of Examples 11-12, wherein storing the power data indicative of the MTPLs for the UE-supported frequency bands includes storing an indication of a respective MTPL for each power class supported by the UE. 
     Example 14. The method of any one of Examples 11-13, wherein determining the maximum UL duty cycle for the connection is further based on a number of operational UL transceivers of the UE. 
     Example 15. The method of any one of Examples 11-14, wherein: the UE includes only a single operational UL transceiver, and determining the maximum UL duty cycle for the connection based on the power data comprises selecting a lowest maximum UL duty cycle among respective maximum UL duty cycles of a candidate set of UE-supported frequency bands to which the power data corresponds. 
     Example 16. The method of any one of Examples 11-14, wherein: the UE includes multiple operational UL transceivers; and determining the maximum UL duty cycle of the UE for the connection based on the power data includes: 
     selecting a lowest maximum UL duty cycle among respective maximum UL duty cycles of a candidate set of UE-supported frequency bands to which the power data corresponds; and decreasing the selected lowest maximum UL duty cycle based on a total number of the multiple operational UL transceivers to determine the maximum UL duty cycle of the UE for the connection. 
     Example 17. The method of Example 16, wherein decreasing the selected lowest maximum UL duty cycle based on the total number of the multiple operational UL transceivers comprises proportionally decreasing the selected lowest maximum UL duty cycle based on the total number of the multiple operational UL transceivers. 
     Example 18. The method of any one of Examples 11-17, wherein: the UE includes multiple operational UL transceivers; and determining the maximum UL duty cycle of the UE for the connection based on the power data includes: 
     selecting a lowest maximum UL duty cycle among respective maximum UL duty cycles of a candidate set of UE-supported frequency bands to which the power data corresponds; and decreasing the selected lowest maximum UL duty cycle based on respective bandwidths associated with the multiple operational UL transceivers to determine the maximum UL duty cycle of the UE for the connection. 
     Example 19. The method of any one of Examples 1-18, further comprising: determining, by the processing hardware of the UE, an updated maximum UL duty cycle of the UE for the connection based on a change to a carrier configuration; and providing, by the processing hardware of the UE to the base station, an indication of the updated maximum UL duty cycle. 
     Example 20. The method of Example 19, wherein: the change to the carrier configuration includes one of an addition or a removal of one or more carrier components; and determining the updated maximum UL duty cycle for the connection includes determining the updated maximum UL duty cycle for the connection based on a total number of carrier components of the changed carrier configuration. 
     Example 21. The method of any one of Examples 19-20, wherein: the change to the carrier configuration includes one of an addition or a removal of one or more carrier components; and determining the updated maximum UL duty cycle for the connection includes determining the updated maximum UL duty cycle for the connection based on respective bandwidths of the carrier components of the changed carrier configuration. 
     Example 22. The method of any one of Examples 19-21, wherein the request for the capabilities of the UE is a first request for UE capabilities, and providing the indication of the updated maximum UL duty cycle to the base station includes: 
     transmitting, by the processing hardware of the UE to the base station, an indication that the capabilities of the UE have been updated; receiving, by the processing hardware from the base station, a second request for UE capabilities in response to the indication that the capabilities of the UE have been updated; and providing, by the processing hardware to the base station, the indication of the updated maximum UL duty cycle in response to the second request for UE capabilities. 
     Example 23. A User Equipment (UE) configured to perform the method of any one of Examples 1-22. 
     Example 24. The UE of Example 23, configured to operate at any power class of a set of multiple power classes supported by the UE. 
     Example 25. Any one of the preceding Examples in combination with any other one of the preceding Examples. 
     Example 26. A computer-readable medium comprising instructions which, when executed by a processor, cause a user equipment comprising the processor to perform the method of any one of Examples 1-22.