WO2017024432A1

WO2017024432A1 - Enhanced power headroom reporting for uplink carrier aggregation

Info

Publication number: WO2017024432A1
Application number: PCT/CN2015/086333
Authority: WO
Inventors: Haiqin LIU; Bao Vinh Nguyen; Peng Wu; Gang Andy Xiao; Deepak KRISHNAMOORTHI; Vasanth Kumar RAMKUMAR; Shailesh Maheshwari
Original assignee: Qualcomm Inc
Current assignee: Qualcomm Inc
Priority date: 2015-08-07
Filing date: 2015-08-07
Publication date: 2017-02-16
Anticipated expiration: 2018-02-07

Abstract

Enhanced power headroom reporting for uplink carrier aggregation is disclosed. A user equipment may divide power headroom information for multiple cells having configured uplinks into multiple partial power headroom reports, each including power headroom information for one or more cells. Cells may be prioritized for power headroom reporting according to their respective power headroom reporting triggers, cell indices, or other criteria. Multiple partial power headroom reports may be sent in the same transmission time interval and on the same or different carriers. A partial power headroom report may include a truncation indicator. A base station may receive a power headroom report and may determine that the power headroom information is partial. The base station may provide an additional grant for unreported cells and/or modify a transmission parameter for a subsequent uplink transmission.

Description

ENHANCED POWER HEADROOM REPORTING FOR UPLINK CARRIER AGGREGATION

BACKGROUND

FIELD OF THE DISCLOSURE

The present disclosure relates to wireless communication systems and, more particularly, to power headroom reporting for uplink carrier aggregation.

DESCRIPTION OF RELATED ART

Wireless communication systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be multiple-access systems capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power) . Examples of such multiple-access systems include code-division multiple access (CDMA) systems, time-division multiple access (TDMA) systems, frequency-division multiple access (FDMA) systems, and orthogonal frequency-division multiple access (OFDMA) systems.

A wireless multiple-access communication system may include a number of base stations, each simultaneously supporting communication for multiple communication devices, otherwise known as user equipments (UEs) . A base station may communicate with UEs on downlink channels (e.g., for transmissions from a base station to a UE) and uplink channels (e.g., for transmissions from a UE to a base station) .

With closed-loop power control, a UE may use a power headroom reporting procedure to provide its serving base station with information about the difference between the UE’s maximum transmit power and the estimated power for a data transmission. Lack of timely power headroom reporting may cause uplink power information at the base station to be inaccurate, increasing the decoding error rate of uplink transmissions. In the case of uplink carrier aggregation, power headroom reporting issues may be compounded by the need for timely and accurate power headroom information to support communication on multiple component carriers.

SUMMARY

Methods, systems, and devices for enhanced power headroom reporting for uplink carrier aggregation are disclosed. The disclosed techniques include an enhanced power headroom reporting procedure for reporting power headroom information for a set of cells. Power headroom information may be reported in partial power headroom reports. The determination as to whether partial power headroom reports will be used may be based on the capacity of granted uplink resources. Each partial power headroom report may include power headroom information for one or more cells, which may be prioritized for power headroom reporting according to various factors.

The described techniques for enhanced power headroom reporting may use an existing (e.g., extended power headroom report Medium Access Control (MAC) control element, etc. ) or new control element and may include a truncation indicator, which may indicate a partial power headroom report or additional information such as a number of unreported cells. A base station may receive a power headroom report and may determine that the power headroom information is partial based on the truncation indicator. The base station may provide an additional grant for unreported cells and/or modify a transmission parameter for a subsequent uplink transmission on an unreported cell.

In one example, a method of wireless communication is disclosed. The method may include detecting, at a user equipment, a trigger for reporting power headroom information in relation to a plurality of cells in an uplink carrier aggregation configuration, identifying a grant of uplink resources for a first uplink transmission by the user equipment on an uplink data channel, determining whether a power headroom report for the plurality of cells exceeds a capacity of the uplink resources, and sending, in the first uplink transmission, a partial power headroom report comprising the power headroom information for a subset of the plurality of cells based at least in part on a result of the determining.

An apparatus for wireless communication is disclosed. The apparatus may include means for detecting a trigger for reporting power headroom information in relation to a plurality of cells in an uplink carrier aggregation configuration, means for identifying a grant of uplink resources for a first uplink transmission by the apparatus on an uplink data channel, means for determining whether a power headroom report for the plurality of cells exceeds a capacity of the uplink resources, and means for sending, in the first uplink transmission, a partial power headroom report comprising power headroom information for a subset of the plurality of cells based at least in part on a result of the determining.

A further apparatus for wireless communication is disclosed. The apparatus may include at least one processor, memory in electronic communication with the at least one processor, and instructions stored in the memory and operable, when executed by the at least one processor, to cause the apparatus to detect a trigger for reporting power headroom information in relation to a plurality of cells in an uplink carrier aggregation configuration, identify a grant of uplink resources for a first uplink transmission by the apparatus on an uplink data channel, determine whether a power headroom report for the plurality of cells exceeds a capacity of the uplink resources, and send, in the first uplink transmission, a partial power headroom report comprising power headroom information for a subset of the plurality of cells based at least in part on a result of the determining.

A non-transitory computer-readable medium storing code for wireless communication is disclosed. The code may include instructions executable to detect, at a user equipment, a trigger for reporting power headroom information in relation to a plurality of cells in an uplink carrier aggregation configuration, identify a grant of uplink resources for a first uplink transmission by the user equipment on an uplink data channel, determine whether a power headroom report for the plurality of cells exceeds a capacity of the uplink resources, and send, in the first uplink transmission, a partial power headroom report comprising the power headroom information for a subset of the plurality of cells based at least in part on a result of the determining.

Some examples of the method, apparatuses, or non-transitory computer-readable medium described herein may further include processes, features, means, or instructions for prioritizing the plurality of cells for reporting the power headroom information, and for identifying the subset of the plurality of cells based at least in part on the prioritizing and the capacity of the uplink resources. The prioritizing the plurality of cells may be based at least in part on: respective path loss change values associated with the plurality of cells, respective periodic power headroom reporting timer values associated with the plurality of cells, respective prohibit power headroom reporting timer values associated with the plurality of cells, or respective indexes of the plurality of cells, or any combination thereof.

In some examples of the method, apparatuses, or non-transitory computer-readable medium described herein, the partial power headroom report comprises a truncation indicator. The truncation indicator may signal that complete power headroom information for the plurality of cells is not reported and may also indicate a number of the cells of the plurality of cells for which power headroom information is not reported in the partial power headroom report.

In some examples of the method, apparatuses, or non-transitory computer-readable medium described herein, the truncation indicator comprises at least one logical channel identifier. Some examples may include processes, features, means, or instructions for sending, in a second uplink transmission, a second partial power headroom report comprising the power headroom information for a second subset of the plurality of cells.

In some examples of the method, apparatuses, or non-transitory computer-readable medium described herein, the second uplink transmission is sent in a same transmission time interval as the first uplink transmission. The partial power headroom report may be sent using a partial extended power headroom report control element comprising the power headroom information for a primary cell and at least one secondary cell.

In some examples of the method, apparatuses, or non-transitory computer-readable medium described herein, the partial power headroom report comprises a truncated power headroom report control element. The truncated power headroom report control element may include the power headroom information for one or more cells and an index of the one or more cells.

The disclosed techniques also include managing uplink power control at a base station based on power headroom information reported in partial power headroom reports. A method of wireless communication at a base station may include receiving, in a first uplink transmission from a user equipment, a power headroom report comprising power headroom information for a first cell of a plurality of cells of an uplink carrier aggregation configuration of the user equipment, determining whether power headroom information for one or more second cells of the plurality of cells is not included in the power headroom report, and allocating resources for a second uplink transmission from the user equipment based at least in part on a result of the determining.

An apparatus for wireless communication is disclosed. The apparatus may include means for receiving, in a first uplink transmission from a user equipment, a power headroom report comprising power headroom information for a first cell of a plurality of cells of an uplink carrier aggregation configuration of the user equipment, means for determining whether power headroom information for one or more of second cells of the plurality of cells is not included in the power headroom report, and means for allocating resources for a second uplink transmission from the user equipment based at least in part on a result of the determining.

A further apparatus for wireless communication is disclosed. The apparatus may include at least one processor, memory in electronic communication with the at least one processor, and instructions stored in the memory and operable, when executed by the at least one processor, to cause the apparatus to receive, in a first uplink transmission from a user equipment, a power headroom report comprising power headroom information for a first cell of a plurality of cells of an uplink carrier aggregation configuration of the user equipment, determine whether power headroom information for one or more second cells of the plurality of cells is not included in the power headroom report, and allocate resources for a second uplink transmission from the user equipment based at least in part on a result of the determining.

A non-transitory computer-readable medium storing code for wireless communication is disclosed. The code may include instructions executable to receive, in a first uplink transmission from a user equipment, a power headroom report comprising power headroom information for a first cell of a plurality of cells of an uplink carrier aggregation configuration of the user equipment, determine whether power headroom information for one or more second cells of the plurality of cells is not included in the power headroom report, and allocate resources for a second uplink transmission from the user equipment based at least in part on a result of the determining.

Some examples of the method, apparatuses, or non-transitory computer-readable medium described herein may further include processes, features, means, or instructions for adjusting a transmission parameter for a subsequent uplink transmission by the user equipment in response to determining that power headroom information for the one or more second cells is not included in the power headroom report. The transmission parameter may include any of a cell for the subsequent uplink transmission, a modulation and coding scheme for the subsequent uplink transmission, an amount of physical resources for the subsequent uplink transmission, a transport block size for the subsequent uplink transmission, a transmit power control command for the subsequent uplink transmission, or combinations thereof.

In some examples of the method, apparatuses, or non-transitory computer-readable medium described herein, the power headroom report comprises a truncation indicator, and allocating resources for the second uplink transmission may be based at least in part on the truncation indicator. The truncation indicator may signal that power headroom information for the one or more second cells is not included with the power headroom report and may also indicate a number of the unreported cells.

The foregoing has outlined rather broadly the features and technical advantages of examples according to the disclosure in order that the detailed description which follows may be better understood. Additional features and advantages will be described hereinafter. The concepts and specific examples disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. Such equivalent constructions do not depart from the scope of the appended claims. Characteristics of the concepts disclosed herein, both their organization and method of operation, together with associated advantages will be better understood from the following description when considered in connection with the accompanying figures. Each of the figures is provided for the purpose of illustration and description only, and does not limit the scope of the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

A further understanding of the nature and advantages of the present invention may be realized by reference to the drawings. In the figures, similar components or features may have the same reference label. Further, various components of the same type may be distinguished by following the reference label by a dash and a second label that distinguishes among the similar components. If only the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the second reference label.

FIG. 1 shows an exemplary wireless communications system in accordance with various aspects of the disclosure；

FIG. 2 shows an exemplary process flow for enhanced power headroom reporting in accordance with various aspects of the present disclosure；

FIGs. 3A-3C show timing diagrams of partial power headroom reports for enhanced power headroom reporting for uplink carrier aggregation in accordance with various aspects of the present disclosure；

FIG. 4 shows an exemplary diagram of a protocol data unit with a partial power headroom report including a truncation indicator in accordance with various aspects of the present disclosure；

FIG. 5 shows an example of a truncated power headroom report control element in accordance with various aspects of the present disclosure；

FIG. 6 shows an exemplary process flow for enhanced power headroom reporting for uplink carrier aggregation in accordance with various aspects of the present disclosure；

FIG. 7 shows a block diagram of a wireless device configured for enhanced power headroom reporting for uplink carrier aggregation in accordance with various aspects of the present disclosure；

FIG. 8 shows a block diagram of a wireless device configured for enhanced power headroom reporting for uplink carrier aggregation in accordance with various aspects of the present disclosure；

FIG. 9 shows a diagram of a system including a UE configured for enhanced power headroom reporting for uplink carrier aggregation in accordance with various aspects of the present disclosure；

FIG. 10 shows a block diagram of a wireless device configured for enhanced power headroom reporting for uplink carrier aggregation in accordance with various aspects of the present disclosure；

FIG. 11 shows a diagram of a system including a base station configured for enhanced power headroom reporting for uplink carrier aggregation in accordance with various aspects of the present disclosure；

FIG. 12 illustrates a method for enhanced power headroom reporting for uplink carrier aggregation in accordance with various aspects of the present disclosure； and

FIG. 13 illustrates a method for enhanced power headroom reporting for uplink carrier aggregation in accordance with various aspects of the present disclosure.

DETAILED DESCRIPTION

Techniques for enhanced power headroom reporting in uplink carrier aggregation are disclosed. A UE may determine whether a power headroom report for a set of cells exceeds a capacity of granted uplink resources. In such instances, a UE may send a partial power headroom report that includes power headroom information for a subset of the cells. Power headroom information for multiple cells having configured uplinks may be divided into multiple partial power headroom reports. Each partial power headroom report may include power headroom information for one or more cells. Cells may be prioritized for power headroom reporting according to power headroom triggers, cell indices, or other criteria. Multiple partial power headroom reports may be sent in the same transmission time interval and may be sent on the same or a different carrier. A base station may receive a power headroom report and may determine that the power headroom information is partial based on one or more indicators. The base station may provide an additional grant for unreported cells and/or modify a transmission parameter for a subsequent uplink transmission by the user equipment.

The following description provides examples which do not limit the scope or applicability of the appended claims. Changes may be made in the function and arrangement of elements discussed without departing from the scope of the disclosure. Various examples may omit, substitute, or add various procedures or components as appropriate. For instance, the methods described may be performed in an order different from that described, and various steps may be added, omitted, or combined. Also, it is specifically contemplated that features described in connection with some examples may be combined with those described in other examples such that they are not mutually exclusive unless clearly indicated as such.

FIG. 1 shows an exemplary wireless communications system 100 in accordance with various aspects of the disclosure. The wireless communications system 100 includes base stations 105, UEs 115, and a core network 130. The core network 130 may provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. The base stations 105 interface with the core network 130 through backhaul links 132 (e.g., S1, etc. ) and may perform radio configuration and scheduling for communication with the UEs 115, or may operate under the control of a base station controller (not shown) . In various examples, the base stations 105 may communicate, either directly or indirectly (e.g., through core network 130) , with each other over backhaul links 134 (e.g., X1, etc. ) , which may be wired or wireless communication links.

The base stations 105 may wirelessly communicate with the UEs 115 via one or more base station antennas. Each of the base station 105 sites may provide communication coverage for a respective geographic coverage area 110. In some examples, a base station 105 may be referred to as a base transceiver station, a radio base station, an access point, a radio transceiver, a NodeB, eNodeB (eNB) , Home NodeB, a Home eNodeB, or like terminology. The geographic coverage area 110 for a base station 105 may be divided into sectors making up only a portion of the coverage area (not shown) . The wireless communications system 100 may include base stations 105 of different types and/or power classes (e.g., macro and/or small cell base stations) . Geographic coverage areas 110 may overlap for different radio access technologies.

The UEs 115 are dispersed throughout the wireless communications system 100, and each UE 115 may be stationary or mobile. A UE 115 may also include, or be referred to by those skilled in the art as, a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless device, a wireless communications device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile client, a client, or some other suitable terminology. A UE 115 may be a cellular phone, a personal digital assistant (PDA) , a wireless modem, a wireless communication device, a handheld device, a tablet computer, a laptop computer, a cordless phone, a wireless local loop (WLL) station, or the like. A UE may be able to communicate with various types of base stations and network equipment including macro eNBs, small cell eNBs, relay base stations, and the like.

The communication links 125 shown in wireless communications system 100 may include uplink (UL) transmissions from a UE 115 to a base station 105, and/or downlink (DL) transmissions, from a base station 105 to a UE 115. The downlink transmissions may also be called forward link transmissions while the uplink transmissions may also be called reverse link transmissions. Each communication link 125 may include one or more carriers, where each carrier may have a distinct system bandwidth and may be made up of multiple sub-carriers. A modulated transmission for each carrier may be made up of multiple signals (e.g., waveform signals of different frequencies) modulated according to the various radio technologies described above. Each modulated signal may be sent on a different sub-carrier and may carry control information (e.g., reference signals, control channels, etc. ) , overhead information, user data, etc. The communication links 125 may support bidirectional communications using frequency division duplexing (FDD) (e.g., using paired spectrum resources) or time division duplexing (TDD) operation (e.g., using unpaired spectrum resources) .

In some examples, the wireless communications system 100 is an LTE/LTE-A network. In LTE/LTE-A networks, the term evolved Node B (eNB) may be generally used to describe the base stations 105, while the term UE may be generally used to describe the UEs 115. The wireless communications system 100 may be a Heterogeneous LTE/LTE-A network in which different types of eNBs provide coverage for various geographical regions. The term “cell” is a 3GPP term that can be used to describe a base station, a carrier or component carrier associated with a base station, or a coverage area (e.g., sector, etc. ) of a carrier or base station, depending on context.

Communication networks that may accommodate some of the various disclosed examples may be packet-based networks that operate according to a layered protocol stack. In the user plane, communications at the bearer or Packet Data Convergence Protocol (PDCP) layer may be IP-based. A Radio Link Control (RLC) layer may perform packet segmentation and reassembly to communicate over logical channels. A Medium Access Control (MAC) layer may perform priority handling and multiplexing of logical channels into transport channels. The MAC layer may also support Hybrid ARQ (HARQ) operation to provide retransmission at the MAC layer and improve link efficiency. In the control plane, the Radio Resource Control (RRC) protocol layer may provide establishment, configuration, and maintenance of an RRC connection between a UE 115 and the base stations 105 or core network 130 supporting radio bearers for the user plane data. At the Physical (PHY) layer, the transport channels may be mapped to Physical Channels.

In some embodiments of the wireless communications system 100, base stations 105 and/or UEs 115 may include multiple antennas for employing antenna diversity schemes to improve communication quality and reliability between base stations 105 and UEs 115. Additionally or alternatively, base stations 105 and/or UEs 115 may transmit multiple spatial layers carrying the same or different coded data using multiple-input, multiple-output (MIMO) techniques to take advantage of multi-path environments.

Wireless communications system 100 may support operation on multiple cells or carriers, a feature which may be referred to as carrier aggregation (CA) or multi-carrier operation. The term “component carrier” (CC) may refer to each of the multiple carriers utilized by a UE in carrier aggregation operation. The terms “carrier, ” “component carrier, ” “cell, ” and “channel” may be used interchangeably herein. For instance, component carriers may be of various bandwidths and may be utilized independently or in combination with other component carriers. Each component carrier may provide the same capabilities as an isolated carrier based on release 8 or release 9 of the Long Term Evolution (LTE) standard. Multiple component carriers may be aggregated or utilized concurrently to provide some UEs 115 with greater bandwidth and, e.g., higher data rates. Individual component carriers may be backwards compatible with legacy UEs 115 (e.g., single-carrier UEs 115 implementing LTE release 8 or release 9) , and some UEs 115 (e.g., UEs 115 implementing release 10+LTE versions) , may be configured with multiple component carriers in a multi-carrier mode. A carrier used for downlink communication may be referred to as a DL CC, and a carrier used for uplink communication may be referred to as an UL CC. A UE 115 may be configured with multiple DL CCs and one or more UL CCs for carrier aggregation. Each carrier may be used to transmit control information (e.g., reference signals, control channels, etc. ) , overhead information, data, etc. A UE 115 may communicate with a single base station 105 utilizing multiple carriers, and may also communicate with multiple base stations simultaneously on different carriers. Carrier aggregation may be used with both FDD and TDD component carriers.

Each cell of a base station 105 may include a DL CC and optionally an UL CC. The coverage area 110 of each serving cell for a base station 105 may be different (e.g., CCs on different frequency bands may experience different path loss) . In some examples, one carrier is designated as the primary cell (PCell) , or primary component carrier (PCC) , for a UE 115. Primary cells may be semi-statically configured by higher layers (e.g., RRC, etc. ) on a per-UE basis. Certain uplink control information (UCI) , e.g., acknowledgement (ACK) /NACK, channel state information (CSI) , and scheduling information transmitted on the physical uplink control channel (PUCCH) , are carried by the primary cell. Additional carriers may be designated as secondary cells (SCells) , or secondary component carriers (SCC) . SCells may likewise be semi-statically configured on a per-UE basis. In some cases, SCells may not include or be configured to transmit the same control information as the PCell. In other cases, one or more SCells may be designated to carry a PUCCH, and the SCells may be organized into PUCCH groups for which an SCC may be designated to carry the associated UCI. Some wireless networks may utilize enhanced CA operations based on a large number of carriers (e.g., between 5 and 32 carriers) , operation in unlicensed spectrum, or use of enhanced CCs.

In some cases, configured SCells for the UE 115 may be activated or deactivated by the eNB 105 based on the presence or absence of data traffic or other factors. For example, activation and deactivation commands for configured SCells may be carried in MAC signaling. When an SCell is deactivated, the UE 115 does not need to receive the downlink CC, does not need to monitor for control information, does not transmit in the corresponding uplink CC, and is not required to perform channel quality information (CQI) measurements. Upon deactivation of an SCell, the UE 115 may also flush all HARQ buffers associated with the SCell. Conversely, when an SCell is active, the UE 115 receives control information or data transmissions for the SCell, and is expected to be able to perform CQI measurements. The activation/deactivation mechanism is based on the combination of a MAC control element and deactivation timers. The MAC control element carries a bitmap for the activation and deactivation of SCells such that SCells can be activated and deactivated individually, and a single activation/deactivation command can activate/deactivate a subset of the SCells. Generally, one deactivation timer is maintained per SCell. In some cases, all the timers for a UE 115 may be configured with a common value via RRC configuration. However, the UEs 115 are not limited to one timer per SCell, or to all timers being configured with a common value.

A UE 115 may coordinate transmit power (e.g., for PUCCH and/or a physical uplink shared channel (PUSCH) , etc. ) with a serving base station to mitigate interference, improve the UL data rate, and prolong battery life. Uplink power control may include a combination of open-loop and closed-loop mechanisms. In open-loop power control, the UE 115 transmit power depends on estimates of the downlink path-loss and channel configuration. In closed-loop power control, the network can directly control the UE 115 transmit power using explicit power-control commands. Open-loop power control may be used for initial access, whereas both open and closed loop control may be used for UL control and data transmission. A UE 115 may determine power using an algorithm that takes into account a maximum transmission power limit, a target base station receive power, path loss, modulation and coding scheme (MCS) , the number of resources used for transmission, and the format of the transmitted data (e.g., PUCCH format) . Power adjustments may be made by a base station 105 using transmit power control (TPC) messages, which may incrementally adjust the transmit power of a UE 115 as appropriate.

The UE 115 may use a power headroom reporting procedure to provide a serving eNB 105 with information about the difference between the UE’s maximum transmit power and the estimated power for a data transmission. The reported power headroom information may be used by the eNB 105 to manage uplink transmissions. For example, the reported power headroom information may be used by the eNB 105 to determine transmit power using closed loop power control, to determine MCS selection for uplink transmissions, and to determine a resource allocation among the UEs 115 in its coverage area. The reported power headroom information may be based on the configured UE transmit power, the bandwidth of a PUSCH resource assignment used for transmission of the PHR, cell-specific or transmission type (e.g., dynamic, semi-persistent, (re) transmissions, etc. ) offsets, a fractional power control constant that may be cell-specific, downlink path loss estimate calculated at the UE 115, an MCS dependent offset, and/or the current PUSCH power control adjustment state (e.g., accumulated TPC commands, etc. ) .

In LTE systems, a power headroom report (PHR) may be triggered at the MAC layer based on a change in measured path loss (PL) , configuration or reconfiguration of power headroom reporting, cell reconfiguration, or one or more reporting timers. For example, the MAC layer may generate a PHR when the PL has changed more than a configured path loss threshold (e.g., dl-PathLossChange, etc. ) and a prohibit PHR timer (e.g., prohibitPHR-Timer, etc. ) has expired, upon expiration of a periodic PHR timer (e.g., periodicPHR-Timer, etc. ) , upon configuration or reconfiguration of power headroom reporting by upper layers, configuration or activation of additional cells for carrier aggregation, or a change in power backoff due to power management (e.g., greater than dl-PathLossChange) . While the PHR is generated in the MAC layer based on the trigger, the PHR is transmitted using a MAC control element in the PUSCH (e.g., of the PCell or an SCell) . Thus, subsequent to the triggering event, the UE 115 waits for allocated uplink data resources to format and transmit the PHR.

If a CA configuration for the UE 115 includes at least one SCell with a configured uplink, power headroom may be reported using an extended PHR MAC control element that includes power headroom information for the PCell and power headroom information for each activated SCell with a configured uplink carrier. In LTE systems, the extended PHR MAC control element is of variable size and includes at least one octet indicating the presence of power headroom information per SCell using a 7-bit bitmap corresponding to SCell indexes and Type 1 power headroom field for the PCell and each activated SCell. The extended PHR MAC control element may also include a Type 2 power headroom field for the PCell where simultaneous transmission on PUSCH and PUCCH is enabled. Each Type 1 or Type 2 power headroom field includes a first octet with a six-bit PH field indicating the power headroom level, a one-bit P field indicating whether the MAC entity applies power backoff due to power management, and a one-bit V field indicating the presence of an octet containing a P_CMAX, c field. If the V field is set to a 1, the power headroom field includes an additional octet including the six-bit P_CMAC, c field and two reserved bits.

For a given number of SCells with configured and activated uplinks, N_{UL_SCC}, the extended PHR MAC control element may have a minimum size of 2+N_{UL_SCC} octets where simultaneous transmission on PUSCH and PUCCH is not enabled and P_CMAX, c is not reported, and a minimum size of 5+2*N_{UL_SCC} octets where simultaneous transmission on PUSCH and PUCCH is enabled and P_CMAX, c is reported for each uplink carrier. In addition, a protocol data unit (PDU) for reporting power headroom information includes at least a MAC header with a MAC PDU subheader for indicating the extended PHR MAC control element. Thus, a minimum PDU size for reporting power headroom using the extended PHR MAC control element may be between 4 and 8 octets, depending on UE configuration and reported fields.

In some cases, the capacity for reporting power headroom information in allocated uplink resources may be relatively small. For example, a grant may allocate a relatively small number of resource blocks for the UE for the uplink, and a low MCS index may result in a small transport block size. Such small grants may only be able to carry a PDU of less than 8 octets. Additionally, logical channel prioritization may prioritize other information over power headroom reporting, which may reduce the available uplink resources for power headroom reporting. In particular, where many SCells are configured with an uplink, the extended PHR may exceed the capacity of the allocated or available resources. Because the extended PHR is expected to carry power headroom information for the PCell and each SCell with a configured and activated uplink, the UE may not be able to timely report power headroom information. In such a case, the UE may have to skip the grant for reporting of power headroom information. While the UE can request additional resources, a delay in reporting power headroom information may cause MCS index information or serving cell selection at the base station to be inaccurate, increasing the decoding error rate.

The system of FIG. 1, including the base stations 105 and UEs 115, may be configured for partial power headroom reporting for uplink carrier aggregation. At a UE 115, power headroom information for multiple cells having configured uplinks may be divided into multiple partial power headroom reports. Each partial power headroom report may include power headroom information for one or more cells and may use the extended PHR MAC control element or a truncated PHR MAC control element. Cells may be prioritized for power headroom reporting according to a power headroom trigger, cell index, path loss change, or other factors. Multiple partial power headroom reports may be sent in the same transmission time interval and may be sent on the same or a different carrier. A partial power headroom report may include a truncation indicator, which may be included in a MAC subheader using a predetermined logical channel identifier, and may carry additional information such as a number of unreported cells. A base station 105 may receive a power headroom report and may determine that the power headroom information is partial based on the truncation indicator. The base station 105 may provide an additional grant for unreported cells, suspend uplink grants for unreported cells, or adjust transmission parameter (s) for a subsequent uplink transmission by the user equipment. For example, transmission parameters may adjusted in relation to unreported cells.

FIG. 2 shows an exemplary process flow 200 for enhanced power headroom reporting in accordance with various aspects of the present disclosure. Process flow 200 may illustrate, for example, power headroom reporting for a UE 115-a configured for uplink carrier aggregation by an eNB 105-a. The eNB 105-a may be an eNB 105 described with reference to FIG. 1, while the UE 115-a may be a UE 115 described with reference to FIG. 1.

The UE 115-a may have a carrier aggregation configuration 225 that includes a PCell 230 and one or more SCells 235. As shown in FIG. 2, the carrier aggregation configuration 225 includes multiple SCells 235-a-1…235-a-n with corresponding uplink carriers which may support UL carrier aggregation.

A PHR trigger event 205 may occur, for example when a prohibit PHR timer has expired and the path loss has changed more than a configured threshold for at least one activated serving cell (e.g., PCell 230 or an SCell 235, etc. ) . The PHR trigger event 205 may also be triggered by the expiration of a periodic PHR timer, upon configuration or reconfiguration of power headroom reporting functionality by upper layers, activation of an SCell 235 with a configured uplink, addition of a PCell for a secondary cell group, or when a power backoff has changed more than the path loss threshold. The PHR trigger event 205 may trigger a power headroom reporting procedure which may format and send the PHR in allocated UL resources.

The eNB 105-a may send an UL resource grant 210-a (e.g., via downlink control information (DCI) , etc. ) , allocating resources of an uplink data channel (e.g., PUSCH of the PCell 230 or one of the configured SCells 235, etc. ) .

The UE 115-a may determine at 215 that there is a pending trigger for the power headroom reporting procedure and may determine an amount of power headroom information to report. The UE 115-a may determine that a PHR including power headroom information for the PCell 230 and SCells 235 exceeds the available UL resources allocated by the UL resource grant 210-a and proceed to generate a partial PHR. For example, the UL resource grant 210-a may be a small grant and the allocated UL resources may have a relatively low capacity (e.g., less than 6 or 8 octets, etc. ) , or the remaining UL resources allocated by the UL resource grant 210-a after logical channel prioritization may be limited

The UE 115-a may send a partial PHR 220-awhich includes power headroom information for a subset of cells in the allocated UL resources. The subset of cells for which power headroom information is reported in the partial PHR 220-a may be determined based on prioritization of cells with configured uplinks. For example, the UE 115-a may determine a number of cells for which power headroom information can be reported in the available UL resources allocated by the UL resource grant 210-a. The UE 115-a may then determine a subset of cells for which power headroom information is included in the partial PHR 220-a based on the number of cells and the prioritization.

The partial PHR 220-a may include a truncation indicator. In some examples, the truncation indicator may be a logical channel identifier (LCID) associated with a partial or truncated power headroom report. For example, the MAC subheader associated with the partial PHR 220-a may have an LCID index corresponding to a partial or truncated power headroom report.

In some examples, the partial PHR 220-a may be formatted according to an extended PHR MAC control element format. A reserved field of the extend PHR MAC control element may be used to carry the truncation indicator. In some cases, additional information may be included. For example, where the truncation indicator includes two or more bits, the truncation indicator may signal a number of secondary cells for which power headroom information is not reported in the partial PHR 220-a.

The partial PHR 220-a may be formatted according to a partial or truncated PHR MAC control element format. Such a format may include power headroom information for one cell and may include information related to a number of cells for which power headroom information is not reported in the partial PHR 220-a. Alternatively, the partial PHR 220-a may include only the truncation indicator and no corresponding power headroom information for uplink carriers configured in carrier aggregation configuration 225. In that case, the report may simply signal to the base station that power headroom information is available which could not be reported.

In some cases, the UE 115-a may report additional power headroom information in additional allocated UL resources. For example, the UE 115-a may receive a second UL resource grant 210-b allocating second UL resources and report a second partial PHR 220-b in the second UL resources. The second UL resources may be on the same or a different carrier, and may be allocated within the same or a different transmission time interval, in some cases. The partial PHR 220-a and partial PHR 220-b may include power headroom information for each configured and activated serving cell. For example, where four SCells are configured with active uplinks, partial PHR 220-a may include power headroom information for the PCell and two of the four SCells (e.g., using the extended PHR MAC control element) while partial PHR 220-b includes power headroom information for the PCell and the remaining two SCells (e.g., also using the extended PHR MAC control element) .

In some cases, the eNB 105-a may determine that power headroom information for one or more cells not in the reported subset of cells is out of date based on receiving partial PHR 220-a and may adjust a transmission parameter for a subsequent uplink transmission from the UE 115-a (e.g., for the uplink transmission scheduled by UL resource grant 210-b, etc. ) to account for uncertainty in power headroom. The transmission parameter may be, for example, the selected cell for the subsequent uplink transmission, the MCS for the subsequent uplink transmission, an amount of physical resources for the subsequent uplink transmission, a transport block size for the subsequent uplink transmission, or a TPC command for the subsequent uplink transmission.

FIGs. 3A-3C show timing diagrams of partial power headroom reports for enhanced power headroom reporting for uplink carrier aggregation in accordance with various aspects of the present disclosure. FIGs. 3A-3C illustrate power headroom reporting over uplink carriers 340-a and 340-b configured for a UE 115 for one or more transmission time intervals (TTIs) 325. Uplink carriers 340-a and 340-b may be, for example, uplink carriers associated with configured and activated cells (e.g., PCell and/or SCell (s) , etc. ) for the UE 115.

In FIGs. 3A-3C, a PHR trigger may occur prior to a TTI_n, for example as the result of a change in path loss for a configured and activated serving cell (e.g., PCell or SCell) . In timing diagram 300-a, first UL resources in UL carrier 340-a may be allocated to the UE 115 for TTI_n 325-a and second UL resources in UL carrier 340-b may be allocated for TTI_n 325-a. The UE 115 may send a first partial PHR 220-c in the first UL resources and a second partial PHR 220-d in the second UL resources.

In timing diagram 300-b, the UE 115 is allocated first UL resources in UL carrier 340-a for TTI_n 325-b and second UL resources in UL carrier 340-b for TTI_n+1 325-c. The UE 115 may send a first partial PHR 220-e in the first UL resources and a second partial PHR 220-f in the second UL resources.

In timing diagram 300-c, the UE 115 is allocated first UL resources in UL carrier 340-a for TTI_n 325-d and second UL resources in UL carrier 340-a for TTI_n+k 325-e. The UE 115 may send a first partial PHR 220-g in the first UL resources and a second partial PHR 220-h in the second UL resources.

Timing diagrams 300-a, 300-b, and 300-c are only examples and partial PHRs may be sent on any combination of allocated UL resources. For example, partial PHRs may be sent on more than two different UL carriers, or in more than two different TTIs, which may be separated by an arbitrary number of other TTIs.

FIG. 4 shows an exemplary diagram of a protocol data unit 400 with a partial power headroom report including a truncation indicator in accordance with various aspects of the present disclosure. Protocol data unit 400 may be, for example, used to send partial PHRs 220 of FIGs. 2 or 3A-3C.

As shown, exemplary PDU 400 includes a header 420, an extended PHR control element 440 and, optionally, padding 450. The header 420 includes a subheader 430 associated with the PHR control element 440. The subheader 430 includes an extension (E) field 432, an LCID field 435 and a reserved (R) field 431. The E field 432 may be a flag indicating whether additional MAC subheaders are present. The LCID field 435 may have an LCID value associated with a truncated power headroom report (TPHR) . The PHR control element 440 may be an extended PHR MAC control element. That is, the TPHR LCID value may indicate the use of the same extended PHR MAC control element as the extended PHR LCID value, but may also indicate that the power headroom information in the corresponding extended PHR MAC control element is partial or truncated information.

The extended PHR MAC control element may include additional information. For example, the extended PHR MAC control element may indicate a number of SCells for which power headroom information is not reported in the partial PHR. In some examples, reserved or unused bits of the extended PHR MAC control element may be used to carry the additional information. For example, the extended PHR MAC control element, when carrying partial information, may include a limited number of SCells that can be reported, and SCells may be indexed in the extended PHR MAC control element according to sorted SCell indexes for active SCells. As a further example, the extended PHR MAC control element, when carrying partial power headroom information, may support reporting for up to four active SCells indexed in order of their SCell indices, and may have an additional field indicating a number of SCells for which power headroom information is not reported.

The TPHR LCID value may be associated with a truncated PHR MAC control element. FIG. 5 shows an example of a truncated power headroom report control element 500 in accordance with various aspects of the present disclosure. The truncated power headroom report control element 500 may for example, the PHR control element 440 of FIG. 4 and may be sent in a MAC PDU using the TPHR LCID. The truncated PHR control element 500 may be used to report partial power headroom information in partial PHRs 220 as described in connection with FIGs. 2 or 3A-3C.

In the example shown, truncated PHR control element 500 includes a first octet with I_n field 520, NU field 530. The I_n field 520 may indicate the cell index of the cell for which power headroom information is reported, where an I_n field value of zero indicates reporting for the PCell and SCells are indexed according to SCell indices. The NU field 530 may indicate a number of cells for which power headroom information is not reported. The first octet may include one or more reserved (R) bits 515. Although illustrated as 3-bit fields, one or more of the I_n field 520 and NU field 530 may be larger or smaller, in some cases.

Power headroom information for the reported cell may include a P field 540 indicating whether power backoff due to power management is applied for the cell n, a V field 550 indicating whether the power headroom value is based on a real transmission or reference format, a PH field 560 indicating the power headroom level for the cell n, and a P_CMAX, n field 570 indicating the maximum power level used for calculating the power headroom level. The third octet may be optional, with the V field 550 (e.g., V＝0) indicating the presence of the P_CMAX, n field 570. The third octet may include one or more reserved (R) bits 515.

Returning to FIG. 4, it should be noted that the PDU 400 may carry additional elements. For example, header 420 may include additional subheaders 430, which may correspond to additional MAC control elements. For example, logical channel prioritization may specify that a buffers status report (BSR) is higher priority than the PHR. Thus, header 420 may include a subheader associated with the BSR MAC control element, and the PDU 400 may include the BSR MAC control element in the payload.

FIG. 6 shows an exemplary process flow 600 for enhanced power headroom reporting for uplink carrier aggregation in accordance with various aspects of the present disclosure. The process flow 600 may illustrate, for example, power headroom reporting performed by a UE 115 (as previously described) having an uplink carrier aggregation configuration including multiple configured uplink carriers.

At block 605, a PHR may be triggered. The PHR may be triggered when a prohibit PHR timer of UE 115 has expired and the path loss has changed more than a configured threshold for at least one activated serving cell (e.g., PCell or SCell, etc. ) . The PHR may also be triggered by the expiration of a periodic PHR timer, upon configuration or reconfiguration of power headroom reporting functionality by upper layers, activation of an SCell with a configured uplink, addition of a PCell for a secondary cell group, or a power backoff has changed more than the path loss threshold.

Based on the PHR trigger at block 605, the process flow 600 may proceed to block 610 where the UE 115 may determine the availability of a grant of UL resources. When a grant of resources for an uplink data channel (e.g., PUSCH of the PCell or an SCell, etc. ) is detected at block 610, process flow 600 may proceed to block 615.

At block 615, the UE 115 may determine power headroom information for all unreported cells with configured uplinks. For example, the first time power headroom information is determined at block 615 after a PHR trigger, the unreported cells may include the PCell and each activated SCell with a configured uplink. If one or more partial PHRs with power headroom information for a subset of cells have been sent, the unreported cells include the cells (PCell and/or activated SCells) not in the reported subset. Determining the power headroom information may include obtaining the power headroom values for the unreported cells (e.g., values for fields of an extended PHR MAC control element) .

The process flow 600 may proceed to block 620 where it is determined whether a size of a PHR with power headroom information for the unreported cells would exceed the UL resources allocated by the grant. For example, the number of octets of the PDU including the PHR may be compared to a capacity of the UL resources (e.g., based on transport block size and MCS, etc. ) .

When a size of the PHR (i.e., the PDU including the PHR) with power headroom information for all unreported cells would not exceed the allocated UL resources at block 620, the UE 115 may send the PHR at block 625 and return to block 605 to detect another PHR trigger. The PDU used to send the PHR at block 625 may include additional information (e.g., data traffic, additional MAC control elements, padding, etc. ) . Thus, sending the PHR at block 625 may include sending a full PHR including power headroom information for the PCell and each activated SCell, or a partial PHR including power headroom information for cells not reported in one or more partial PHRs sent based on the PHR trigger at block 605. Sending the PHR at block 625 may include resetting timers associated with power headroom reporting such as a prohibit PHR timer or periodic PHR timer.

When a size of the PHR would exceed the allocated UL resources at block 620, the UE 115 may prioritize the unreported cells for power headroom reporting at block 630. Prioritizing the unreported cells may be based on, for example, power headroom triggers associated with the plurality of secondary cells (e.g., time period since the last triggering event, etc. ) , respective path loss change values associated with the plurality of secondary cells, respective indices of the plurality of secondary cells, or combinations of these factors (e.g., prioritized first by one factor and then by other factors, etc. ) . In some cases, prohibit and/or periodic timers may be maintained for each cell, in which case prioritizing may also be based on the respective periodic power headroom reporting timer values or respective prohibit power headroom reporting timer values.

At block 635, The UE 115 may generate and send a partial PHR in the allocated UL resources based on the prioritization at block 630. The partial PHR may include, for example, power headroom information for a subset of cells having the highest priority based on the prioritization at block 630. For example, the UE 115 may have four SCells with configured and active uplinks and it may be determined at block 635 that power headroom information for the PCell and two SCells can be reported in the partial PHR given the size of the allocated or remaining UL resources (e.g., after logical channel prioritization) . The partial PHR may then be generated and sent with power headroom information for the PCell and the two SCells having the highest priority for power headroom reporting.

At block 640, the UE 115 may determine the unreported cells for power headroom reporting based on the power headroom trigger at block 605. For example, if four SCells have configured and activated uplinks and power headroom information for the PCell and two SCells has been reported at block 635, the unreported cells include the other two SCells. The UE 115 determines the availability of additional grants of UL resources at block 610 for further processing of power headroom information for the unreported cells.

If, while determining the availability of an uplink grant at block 610, any additional PHR triggers occur, the unreported cells may be updated based on the additional PHR trigger. For example, the triggering cell may be added to the unreported cells, or all cells (e.g., PCell and SCells with configured and active uplinks) may be added to the unreported cells (e.g., new power headroom information may be generated for one or more of the unreported cells, etc. ) , in some cases.

FIG. 7 shows a block diagram of a wireless device 700 configured for enhanced power headroom reporting for uplink carrier aggregation in accordance with various aspects of the present disclosure. Wireless device 700 may be an example of aspects of a UE 115 described with reference to FIGs. 1-6. Wireless device 700 may include a receiver 705, DCI processor 710, MAC control processor 720, and a transmitter 715. These components may include one or more processors configured to control the operation of wireless device 700 in performing respective portions of process 600 and each component may be in communication with the others.

The receiver 705 may receive information such as packets, user data, or control information associated with various information channels (e.g., physical channels, etc. ) . The receiver 705 may pass information on to (e.g., via one or more transport channels, etc. ) the DCI processor 710, the MAC control processor 720, or to other components of wireless device 700.

The MAC control processor 720 may perform functions related to managing communications at the logical channel level. For example, the MAC control processor 720 may perform functions for data transfer including transport format selection, error correction (e.g., HARQ, etc. ) , and logical channel prioritization. The MAC control processor 720 may format information (e.g., data, control information, HARQ information, etc. ) into a transport format specifying physical layer processing to be performed for transmission of the information in a physical channel (e.g., via transmitter 715) .

The MAC control processor 720 may include a PHR trigger component 725, a PHR processor 730, or an uplink transmission multiplexer 735. The PHR trigger component 725 may detect a trigger for reporting power headroom information in relation to a plurality of cells in an uplink carrier aggregation configuration as described with reference to FIGs. 1-6. A trigger for reporting power headroom may occur, for example when a prohibit PHR timer has expired and the path loss has changed more than a configured threshold for at least one activated serving cell (e.g., PCell or SCell, etc. ) . A trigger for reporting power headroom may also occur upon expiration of a periodic PHR timer, upon configuration or reconfiguration of power headroom reporting functionality by upper layers, activation of an SCell with a configured uplink, addition of a PCell for a secondary cell group, when a power backoff has changed more than the path loss threshold, or other events are detected.

The DCI processor 710 may identify a grant of uplink resources for a first uplink transmission by the user equipment on an uplink data channel as described with reference to FIGs. 1-6. The DCI processor 710 may indicate the grant to the components of the MAC control processor 720. The DCI processor 710 may identify subsequent grants of uplink resources and notify the MAC control processor 720.

The PHR processor 730 may determine whether a power headroom report for the plurality of cells exceeds a capacity of the uplink resources as described with reference to FIGs. 1-6. For example, The PHR processor 730 may determine that a PHR including power headroom information for the PCell and SCells (e.g., extended PHR, etc. ) may exceed the available UL resources allocated by the grant. The PHR processor 730 may generate a partial power headroom report comprising the power headroom information for a subset of the plurality of cells. In some examples, the partial power headroom report comprises a partial extended power headroom report control element comprising the power headroom information for a primary cell and at least one secondary cell. In some examples, the partial power headroom report comprises a truncated power headroom report control element. In some examples, the truncated power headroom report control element comprises the power headroom information for one cell and an index of the one cell. The PHR processor 730 may send the partial power headroom report to the uplink transmission multiplexer 735 for formatting into a MAC PDU for transmission via a physical channel (e.g., PUSCH, etc. ) .

The PHR processor 730 may, upon notification by the DCI processor 710 of a subsequent grant of UL resources for a second uplink transmission, generate a second partial power headroom report comprising the power headroom information for a second subset of the plurality of cells. More generally, MAC control processor 720 and, in particular, PHR trigger component 725 and PHR processor 730, may implement portions of process flow 600 shown in FIG. 6 to send partial power headroom reports.

The uplink transmission multiplexer 735 may send the partial power headroom report in the first uplink transmission. In some examples, the partial power headroom report comprises a truncation indicator. As described herein, the truncation indicator may signal partial reporting and, in some cases, may indicate a number of the unreported cells. In some examples, the truncation indicator comprises at least one logical channel identifier. The uplink transmission multiplexer 735 may also send, in the second uplink transmission, a second partial power headroom report. In some examples, the second uplink transmission may be sent in a same transmission time interval as the first uplink transmission.

The transmitter 715 may receive information from the MAC control processor 720 (e.g., via one or more transport channels) and process and transmit the information (e.g., via one or more physical channels, etc. ) . For example, the transmitter 715 may perform encoding of the information for physical channels, mapping of information to physical channels, modulation of physical channels, frequency and time synchronization, power weighting of the physical channels, MIMO antenna processing, and the like.

FIG. 8 shows a block diagram of a wireless device 800 configured for enhanced power headroom reporting for uplink carrier aggregation in accordance with various aspects of the present disclosure. Wireless device 800 may be an example of aspects of device 700 of FIG. 7 and/or a UE 115 described with reference to FIGs. 1-6. Wireless device 800 may include a receiver 705-a, DCI processor 710-a, MAC control processor 720-a, or a transmitter 715-a. Wireless device 800 may also include one or more processors. Each of these components may be in communication with each other.

Receiver 705-a, DCI processor 710-a, MAC control processor 720-a, and transmitter 715-a may implement the functions described above of the receiver 705, DCI processor 710, MAC control processor 720, and transmitter 715 of FIG. 7, respectively.

The PHR processor 730-a may also include a PHR prioritizer 805 and a PHR selector component 810. The PHR prioritizer 805 may prioritize the plurality of cells for the reporting of the power headroom information as described with reference to FIGs. 1-6. In some examples, the prioritizing the plurality of cells may be based at least in part on respective path loss change values associated with the plurality of cells, respective periodic power headroom reporting timer values associated with the plurality of cells, respective prohibit power headroom reporting timer values associated with the plurality of cells, or respective indexes of the plurality of cells, or any combination thereof.

The PHR selector component 810 may identify the subset of the plurality of cells based at least in part on the prioritizing and the capacity of the uplink resources as described with reference to FIGs. 1-6. For example, the PHR selector component 810 may identify a number of cells for which power headroom can be reported and identify the cells having the highest priority.

The components of

wireless devices

700 or 800 may, individually or collectively, be implemented with at least one application specific integrated circuit (ASIC) adapted to perform some or all of the applicable functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores) , on at least one integrated circuit (IC) . In other examples, other types of integrated circuits may be used (e.g., Structured/Platform ASICs, a field programmable gate array (FPGA) , or another semi-custom IC) , which may be programmed in any manner known in the art. The functions of each unit may also be implemented, in whole or in part, with instructions embodied in a memory, formatted to be executed by one or more general or application-specific processors.

FIG. 9 shows a diagram of a system 900 including a UE 115 configured for enhanced power headroom reporting for uplink carrier aggregation in accordance with various aspects of the present disclosure. System 900 may include UE 115-b, which may be an example of a

wireless devices

700 or 800, or a UE 115 described with reference to FIGs. 1-6. UE 115-b may include DCI processor 710-b and MAC control processor 720-b, which may be examples, respectively, of the DCI processors 710 and MAC control processors 720 of FIGs. 7 or 8. UE 115-b may also include components for bi-directional voice and data communications including components for transmitting communications and components for receiving communications. For example, UE 115-b may communicate bi-directionally with base station 105-b or UE 115-c.

UE 115-b may also include a processor 905, and memory 915 (including software (SW) ) 920, a transceiver 935, and one or more antenna (s) 940, each of which may communicate, directly or indirectly, with one another (e.g., via buses 945) . The transceiver 935 may communicate bi-directionally, via the antenna (s) 940 or wired or wireless links, with one or more networks, as described above. For example, the transceiver 935 may communicate bi-directionally with a base station 105 or another UE 115. The transceiver 935 may include a modem to modulate the packets and provide the modulated packets to the antenna (s) 940 for transmission, and to demodulate packets from signals received at the antenna (s) 940. While UE 115-b may include a single antenna 940, UE 115-b may also have multiple antennas 940 capable of concurrently transmitting or receiving multiple wireless transmissions.

The memory 915 may include random access memory (RAM) and read only memory (ROM) . The memory 915 may store computer-readable, computer-executable software/firmware code 920 including instructions that, when executed, cause the processor 905 to perform various functions of the DCI processor 710-b and MAC control processor 720-b (e.g., enhanced power headroom reporting for uplink carrier aggregation, etc. ) . Alternatively, the software/firmware code 920 may not be directly executable by the processor 905 but cause a computer (e.g., when compiled and executed) to perform functions described herein. The processor 905 may include an intelligent hardware device, (e.g., a central processing unit (CPU) , a microcontroller, an ASIC, etc. ) .

FIG. 10 shows a block diagram of a wireless device 1000 configured for enhanced power headroom reporting for uplink carrier aggregation in accordance with various aspects of the present disclosure. Wireless device 1000 may be an example of aspects of a base station 105 described with reference to FIGs. 1-6 or 9. Wireless device 1000 may include a BS receiver 1005, an uplink power manager 1010, a CA resource scheduler 1030, and a BS transmitter 1015. Wireless device 1000 may also include a processor. Each of these components may be in communication with each other.

The BS receiver 1005 may receive information which may be passed on to uplink power manager 1010, and to other components of wireless device 1000. For example, BS receiver 1005 may receive and process one or more physical channels (e.g., PUCCH, PUSCH, etc. ) and pass information to the uplink power manager 1010 and CA resource scheduler 1030 (e.g., via one or more transport channels, etc. ) .

The uplink power manager 1010 may also include a BS PHR Processor 1020 and a power headroom information manager 1025. The BS PHR Processor 1020 may receive, in a first uplink transmission from a UE 115, a power headroom report comprising power headroom information for a first cell of a plurality of cells of an uplink carrier aggregation configuration of the UE 115 as described with reference to FIGs. 1-9. In some examples, the power headroom report comprises a truncation indicator, and the wireless device 1000 may allocate resources for a second uplink transmission based at least in part on the truncation indicator. In some examples, the truncation indicator signals a number of cells in the one or more of the plurality of cells for which power headroom information was not reported.

The power headroom information manager 1025 may determine whether power headroom information for one or more of the plurality of cells is not included in the power headroom report as described with reference to FIGs. 1-9. That is, the power headroom information manager 1025 may determine that the received power headroom report is a partial power headroom report.

The CA resource scheduler 1030 may allocate resources for a second uplink transmission from the UE 115 based at least in part on a result of the determining as described with reference to FIGs. 1-9. The CA resource scheduler 1030 may also adjust a transmission parameter for a subsequent uplink transmission based at least in part on the determining. In some examples, the transmission parameter comprises a cell for the subsequent uplink transmission, a modulation and coding scheme for the subsequent uplink transmission, an amount of physical resources for the subsequent uplink transmission, a transport block size for the subsequent uplink transmission, a transmit power control command for the subsequent uplink transmission, or any combinations thereof.

The BS transmitter 1015 may receive information from the uplink power manager 1010 and CA resource scheduler 1030 and process and transmit the information (e.g., via one or more physical channels, etc. ) . For example, the BS transmitter 1015 may perform encoding of the information for physical channels, mapping of information to physical channels, modulation of physical channels, frequency and time synchronization, power weighting of the physical channels, MIMO antenna processing, and the like.

The components of wireless device 1000 may, individually or collectively, be implemented with at least one ASIC adapted to perform some or all of the applicable functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores) , on at least one IC. In other examples, other types of integrated circuits may be used (e.g., Structured/Platform ASICs, a field programmable gate array (FPGA) , or another semi-custom IC) , which may be programmed in any manner known in the art. The functions of each unit may also be implemented, in whole or in part, with instructions embodied in a memory, formatted to be executed by one or more general or application-specific processors.

FIG. 11 shows a diagram of a system 1100 including a base station 105 configured for enhanced power headroom reporting for uplink carrier aggregation in accordance with various aspects of the present disclosure. System 1100 may include base station 105-c, which may be an example of a wireless device 1000 or a base station 105 described with reference to FIGs. 1-6, 9 or 10. Base station 105-c may include an uplink power manager 1010-a and a CA resource scheduler 1030-a, which may be examples of the uplink power manager 1010 and CA resource scheduler 1030 of FIG. 10, respectively. Base station 105-c may also include components for bi-directional voice and data communications including components for transmitting communications and components for receiving communications. For example, base station 105-c may communicate bi-directionally with UE 115-d or UE 115-e.

In some cases, base station 105-c may have one or more wired backhaul links. Base station 105-c may have a wired backhaul link (e.g., S1 interface, etc. ) to the core network 130-a, which may be an example of the core network 130 of FIG. 1. Base station 105-c may also communicate with other base stations 105, such as base station 105-m and base station 105-n via inter-base station backhaul links (e.g., an X2 interface) . Each of the base stations 105 may communicate with UEs 115 using the same or different wireless communications technologies. In some cases, base station 105-c may communicate with other base stations such as 105-m or 105-n utilizing base station communication component 1125. In some examples, base station communication component 1125 may provide an X2 interface within an LTE/LTE-A wireless communication network technology to provide communication between some of the base stations 105. In some examples, base station 105-c may communicate with other base stations through core network 130-a. In some cases, base station 105-c may communicate with the core network 130-a through network communications component 1130.

The base station 105-c may include a processor 1105, memory 1115 (including software (SW) 1120) , transceiver 1135, and antenna (s) 1140, which each may be in communication, directly or indirectly, with one another (e.g., over bus system 1145) . The transceivers 1135 may be configured to communicate bi-directionally, via the antenna (s) 1140, with the UEs 115, which may be multi-mode devices. The transceiver 1135 (or other components of the base station 105-c) may also be configured to communicate bi-directionally, via the antennas 1140, with one or more other base stations (not shown) . The transceiver 1135 may include a modem configured to modulate the packets and provide the modulated packets to the antennas 1140 for transmission, and to demodulate packets received from the antennas 1140. The base station 105-c may include multiple transceivers 1135, each with one or more associated antennas 1140. The transceiver 1135 may be an example of a combined BS receiver 1005 and BS transmitter 1015 of FIG. 10.

The memory 1115 may include RAM and ROM. The memory 1115 may also store computer-readable, computer-executable software code 1120 containing instructions that are configured to, when executed, cause the processor 1105 to perform various functions of the uplink power manager 1010-a or CA resource scheduler 1030-a (e.g., processing power headroom reports, determining whether received power headroom reports are partial reports, allocating additional uplink resources, adjusting transmission parameters based on received partial power headroom reports, etc. ) . Alternatively, the software 1120 may not be directly executable by the processor 1105 but be configured to cause the computer, e.g., when compiled and executed, to perform functions described herein. The processor 1105 may include an intelligent hardware device, e.g., a CPU, a microcontroller, an ASIC, etc. The processor 1105 may include various special purpose processors such as encoders, queue processing modules, base band processors, radio head controllers, digital signal processor (DSPs) , and the like.

The base station communication component 1125 may manage communications with other base stations 105. In some cases, the base station communication component 1125 may include a controller or scheduler for controlling communications with UEs 115 in cooperation with other base stations 105. For example, the base station communication component 1125 may coordinate scheduling for transmissions to UEs 115 for various interference mitigation techniques such as beamforming or joint transmission.

FIG. 12 illustrates a method 1200 for enhanced power headroom reporting for uplink carrier aggregation in accordance with various aspects of the present disclosure. The operations of method 1200 may be implemented by a UE 115 or its components as described with reference to FIGs. 1-9 and 11. For example, the operations of method 1200 may be performed by the DCI processor 710 or MAC control processor 720 as described with reference to FIGs. 7-9. In some examples, a UE 115 may execute a set of codes to control the functional elements described below. Additionally or alternatively, the UE 115 may perform aspects the functions described below using application-specific hardware.

At block 1205, the UE 115 may detect a trigger for reporting power headroom information in relation to a plurality of cells in an uplink carrier aggregation configuration as described with reference to FIGs. 1-6. In certain examples, the operations of block 1205 may be performed by the PHR trigger components 725 as described with reference to FIGs. 7 or 8.

At block 1210, the UE 115 may identify a grant of uplink resources for a first uplink transmission on an uplink data channel as described with reference to FIGs. 1-6. In certain examples, the operations of block 1210 may be performed by the DCI processors 710 as described with reference to FIG. 7 or 8.

At block 1215, the UE 115 may determine whether a power headroom report for the plurality of cells exceeds a capacity of the uplink resources as described with reference to FIGs. 1-6. In certain examples, the operations of block 1215 may be performed by the PHR processors 730 as described with reference to FIGs. 7 or 8.

At block 1220, the UE 115 may send, in the first uplink transmission, a partial power headroom report comprising the power headroom information for a subset of the plurality of cells based at least in part on a result of the determining as described with reference to FIGs. 1-6. In certain examples, the operations of block 1220 may be performed by the uplink transmission multiplexers 735 as described with reference to FIGs. 7 or 8.

FIG. 13 illustrates a method 1300 for enhanced power headroom reporting for uplink carrier aggregation in accordance with various aspects of the present disclosure. The operations of method 1300 may be implemented by a base station 105 or its components as described with reference to FIGs. 1-11. For example, the operations of method 1300 may be performed by the uplink power manager 1010 as described with reference to FIGs. 10 or 11. In some examples, a base station 105 may execute a set of codes to control the functional elements of the base station 105 to perform the functions described below. Additionally or alternatively, the base station 105 may perform aspects the functions described below using special-purpose hardware.

At block 1305, the base station 105 may receive, in a first uplink transmission from a UE 115, a power headroom report comprising power headroom information for a first cell of a plurality of cells of an uplink carrier aggregation configuration of the UE 115 as described with reference to FIGs. 1-6. The power headroom report may include a truncation indicator. The truncation indicator may signal a number of second cells in the plurality of cells for which power headroom information is not reported. In certain examples, the operations of block 1305 may be performed by the BS PHR Processor 1020 as described with reference to FIG. 10.

At block 1310, the base station 105 may determine whether power headroom information for one or more second cells of the plurality of cells is not included in the power headroom report as described with reference to FIGs. 1-6. In certain examples, the operations of block 1310 may be performed by the power headroom information manager 1025 as described with reference to FIG. 10 and may be based on the truncation indicator.

At block 1315, the base station 105 may allocate resources for a second uplink transmission from the user equipment based at least in part on a result of the determining as described with reference to FIGs. 1-6. The allocating of the resources for the second uplink transmission may be based at least in part on the number of unreported cells signaled by the truncation indicator. In certain examples, the operations of block 1315 may be performed by the CA resource scheduler 1030 as described with reference to FIG. 10.

In some cases, the base station 105 may adjust a transmission parameter for a subsequent uplink transmission from the UE 115 at block 1320. For example, the base station 105 may determine that power headroom information for one or more cells is out of date and may adjust transmission parameters to reduce the probability of decoding error or multiple re-transmissions. The transmission parameter may be, for example, the selected cell for the subsequent uplink transmission, the MCS for the subsequent uplink transmission, an amount of physical resources for the subsequent uplink transmission, a transport block size for the subsequent uplink transmission, or a TPC command for the subsequent uplink transmission. In certain examples, the operations of block 1320 may be performed by the CA resource scheduler 1030 as described with reference to FIG. 10.

Thus,

methods

1200 and 1300 may provide for enhanced power headroom reporting for uplink carrier aggregation. It should be noted that

methods

1200 and 1300 describe one possible implementation, and that the operations and the steps may be rearranged or otherwise modified such that other implementations are possible.

Techniques described herein may be used for various wireless communications systems such as CDMA, TDMA, FDMA, OFDMA, single carrier frequency division multiple access (SC-FDMA) , and other systems. The terms “system” and “network” are often used interchangeably. A CDMA system may implement a radio technology such as CDMA2000, Universal Terrestrial Radio Access (UTRA) , etc. CDMA2000 covers IS-2000, IS-95, and IS-856 standards. IS-2000 Releases 0 and A are commonly referred to as CDMA2000 1X, 1X, etc. IS-856 (TIA-856) is commonly referred to as CDMA2000 1xEV-DO, High Rate Packet Data (HRPD) , etc. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. A TDMA system may implement a radio technology such as Global System for Mobile Communications (GSM) . An OFDMA system may implement a radio technology such as Ultra Mobile Broadband (UMB) , Evolved UTRA (E-UTRA) , IEEE 802.11 (Wi-Fi) , IEEE 802.16 (WiMAX) , IEEE 802.20, Flash-OFDM, etc. UTRA and E-UTRA are part of Universal Mobile Telecommunications system (UMTS) . 3GPP Long Term Evolution (LTE) and LTE-advanced (LTE-a) are new releases of Universal Mobile Telecommunications System (UMTS) that use E-UTRA. UTRA, E-UTRA, Universal Mobile Telecommunications System (UMTS) , LTE, LTE-a, and Global System for Mobile communications (GSM) are described in documents from an organization named “3rd Generation Partnership Project” (3GPP) . CDMA2000 and UMB are described in documents from an organization named “3rd Generation Partnership Project 2” (3GPP2) . The techniques described herein may be used for the systems and radio technologies mentioned above as well as other systems and radio technologies. The description herein, however, describes an LTE system for purposes of example, and LTE terminology is used in much of the description above, although the techniques are applicable beyond LTE applications.

The description set forth herein, in connection with the appended drawings, describes example configurations and does not represent all the examples that may be implemented or that are within the scope of the claims. The term “exemplary” used herein means “serving as an example, instance, or illustration, ” and not “preferred” or “advantageous over other examples. ” The detailed description includes specific details for the purpose of providing an understanding of the described techniques. These techniques, however, may be practiced without these specific details. In some instances, well-known structures and devices are shown in block diagram form in order to avoid obscuring the concepts of the described examples.

Information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

The various illustrative blocks and modules described in connection with the disclosure herein may be implemented or performed with a general-purpose processor, a DSP, an ASIC, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices (e.g., a combination of a digital signal processor (DSP) and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration) .

The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Other examples and implementations are within the scope of the disclosure and appended claims. For example, due to the nature of software, functions described above can be implemented using software executed by a processor, hardware, firmware, hardwiring, or combinations of any of these. Features implementing functions may also be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations. Also, as used herein, including in the claims, “or” as used in a list of items (for example, a list of items prefaced by a phrase such as “at least one of” or “one or more of” ) indicates an inclusive list such that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C) .

Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A non-transitory storage medium may be any available medium that can be accessed by a general purpose or special purpose computer. By way of example, and not limitation, non-transitory computer-readable media can comprise RAM, ROM, electrically erasable programmable read only memory (EEPROM) , compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that can be used to carry or store desired program code means in the form of instructions or data structures and that can be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor. Disk and disc, as used herein, include CD, laser disc, optical disc, digital versatile disc (DVD) , floppy disk and Blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above are also included within the scope of computer-readable media.

The description herein is provided to enable a person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the disclosure is not to be limited to the examples and designs described herein but is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.

Claims

A method of wireless communication, comprising:

detecting, at a user equipment, a trigger for reporting power headroom information in relation to a plurality of cells in an uplink carrier aggregation configuration；

identifying a grant of uplink resources for a first uplink transmission by the user equipment on an uplink data channel；

determining whether a power headroom report for the plurality of cells exceeds a capacity of the uplink resources； and

sending, in the first uplink transmission, a partial power headroom report comprising the power headroom information for a subset of the plurality of cells based at least in part on a result of the determining.
The method of claim 1, further comprising:

prioritizing the plurality of cells for the reporting of the power headroom information； and

identifying the subset of the plurality of cells based on the prioritizing and the capacity of the uplink resources.
The method of claim 2, wherein the prioritizing the plurality of cells is based on: respective path loss change values associated with the plurality of cells, respective periodic power headroom reporting timer values associated with the plurality of cells, respective prohibit power headroom reporting timer values associated with the plurality of cells, respective indexes of the plurality of cells, or any combination thereof.
The method of claim 1, wherein the partial power headroom report comprises a truncation indicator.
The method of claim 4, wherein the truncation indicator signals a number of cells of the plurality of cells for which the power headroom information is not reported in the partial power headroom report.
The method of claim 4, wherein the truncation indicator comprises at least one logical channel identifier.
The method of claim 1, further comprising:

sending, in a second uplink transmission, a second partialpower headroom report comprising the power headroom information for a second subset of the plurality of cells.
The method of claim 7, wherein the second uplink transmission is sent in a same transmission time interval as the first uplink transmission.
The method of claim 1, wherein the partial power headroom report comprises a partial extended power headroom report control element with the power headroom information for a primary cell and at least one secondary cell.
The method of claim 1, wherein the partial power headroom report comprises a truncated power headroom report control element.
A method of wireless communication at a base station, comprising:

receiving, in a first uplink transmission from a user equipment, a power headroom report comprising power headroom information for a first cell of a plurality of cells of an uplink carrier aggregation configuration of the user equipment；

determining whether power headroom information for one or more second cells of the plurality of cells is not included in the power headroom report； and

allocating resources for a second uplink transmission from the user equipment based on a result of the determining.
The method of claim 11, further comprising:

adjusting a transmission parameter for a subsequent uplink transmission in response to a determination that the power headroom information for the one or more second cells is not included in the power headroom report.
The method of claim 12, wherein the transmission parameter comprises: a cell for the subsequent uplink transmission, a modulation and coding scheme for the subsequent uplink transmission, an amount of physical resources for the subsequent uplink transmission, a transport block size for the subsequent uplink transmission, a transmit power control command for the subsequent uplink transmission, or any combination thereof.
The method of claim 11, wherein the power headroom report comprises a truncation indicator, and the allocating of the resources for the second uplink transmission is based at least in part on the truncation indicator.
The method of claim 14, wherein the truncation indicator signals a number of cells in the one or more second cells.
An apparatus for wireless communication, comprising:

means for detecting a trigger for reporting power headroom information in relation to a plurality of cells in an uplink carrier aggregation configuration；

means for identifying a grant of uplink resources for a first uplink transmission by the apparatus on an uplink data channel；

means for determining whether a power headroom report for the plurality of cells exceeds a capacity of the uplink resources； and

means for sending, in the first uplink transmission, a partial power headroom report comprising the power headroom information for a subset of the plurality of cells based at least in part on a result of the determining.
The apparatus of claim 16, further comprising:

means for prioritizing the plurality of cells for the reporting of the power headroom information； and

means for identifying the subset of the plurality of cells based at least in part on the prioritizing and the capacity of the uplink resources.
The apparatus of claim 16, wherein the partial power headroom report comprises a truncation indicator.
An apparatus for wireless communication, comprising:

means for receiving, in a first uplink transmission from a user equipment, a power headroom report comprising power headroom information for a first cell of a plurality of cells of an uplink carrier aggregation configuration of the user equipment；

means for determining whether power headroom information for one or more second cells of the plurality of cells is not included in the power headroom report； and

means for allocating resources for a second uplink transmission from the user equipment based at least in part on a result of the determining.
The apparatus of claim 19, further comprising:

means for adjusting a transmission parameter for a subsequent uplink transmission in response to a determination that the power headroom information for the one or more second cells is not included in the power headroom report.
The apparatus of claim 19, wherein the power headroom report comprises a truncation indicator, and the allocation of the resources for the second uplink transmission is based at least in part on the truncation indicator.
An apparatus for wireless communication, comprising:

at least one processor；

memory in electronic communication with the at least one processor； and

instructions stored in the memory and operable, when executed by the at least one processor, to cause the apparatus to:

detect a trigger for reporting power headroom information in relation to a plurality of cells in an uplink carrier aggregation configuration；

identify a grant of uplink resources for a first uplink transmission by the apparatus on an uplink data channel；

determine whether a power headroom report for the plurality of cells exceeds a capacity of the uplink resources； and

send, in the first uplink transmission, a partial power headroom report comprising the power headroom information for a subset of the plurality of cells based at least in part on a result of the determining.
The apparatus of claim 22, wherein the instructions, when executed by the at least one processor, cause the apparatus to:

prioritize the plurality of cells for the reporting of the power headroom information； and

identify the subset of the plurality of cells based at least in part on the prioritizing and the capacity of the uplink resources.
The apparatus of claim 22, wherein the partial power headroom report comprises a truncation indicator.
An apparatus for wireless communication, comprising:

at least one processor；

memory in electronic communication with the at least one processor； and

instructions stored in the memory and operable, when executed by the at least one processor, to cause the apparatus to:

receive, in a first uplink transmission from a user equipment, a power headroom report comprising power headroom information for a first cell of a plurality of cells of an uplink carrier aggregation configuration of the user equipment；

determine whether power headroom information for one or more second cells of the plurality of cells is not included in the power headroom report； and

allocate resources for a second uplink transmission from the user equipment based at least in part on a result of the determining.
The apparatus of claim 25, wherein the instructions, when executed by the at least one processor, cause the apparatus to:

adjust a transmission parameter for a subsequent uplink transmission by the user equipment based at least in part on a determination that the power headroom information for the one or more second cells is not included in the power headroom report.
The apparatus of claim 25, wherein the power headroom report comprises a truncation indicator, and the allocation of the resources for the second uplink transmission is based at least in part on the truncation indicator.
A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable to:

detect, at a user equipment, a trigger for reporting power headroom information in relation to a plurality of cells in an uplink carrier aggregation configuration；

identify a grant of uplink resources for a first uplink transmission by the user equipment on an uplink data channel；

determine whether a power headroom report for the plurality of cells exceeds a capacity of the uplink resources； and

send, in the first uplink transmission, a partial power headroom report comprising the power headroom information for a subset of the plurality of cells based at least in part on a result of the determining.
A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable to:

receive, in a first uplink transmission from a user equipment, a power headroom report comprising power headroom information for a first cell of a plurality of cells of an uplink carrier aggregation configuration of the user equipment；

determine whether power headroom information for one or more second cells of the plurality of cells is not included in the power headroom report； and

allocate resources for a second uplink transmission from the user equipment based at least in part on a result of the determining.