WO2018157271A1

WO2018157271A1 - Techniques and apparatuses for improving efficiency of power tracking in user equipment

Info

Publication number: WO2018157271A1
Application number: PCT/CN2017/075101
Authority: WO
Inventors: Akash Kumar; Fei Lu; Niranjan Kumar VADLAMUDI; Rimal PATEL
Original assignee: Qualcomm Incorporated
Priority date: 2017-02-28
Filing date: 2017-02-28
Publication date: 2018-09-07

Abstract

Certain aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment may determine one or more power tracking parameters for a plurality of uplink carriers based on at least one of respective PAPRs of the plurality of uplink carriers, or respective drive power biases for amplifying the plurality of uplink carriers; and/or configuring, by the user equipment, respective drive powers of a plurality of power amplifiers of the user equipment to amplify respective signals of the plurality of uplink carriers based at least in part on the one or more power tracking parameters, wherein configuring includes configuring, by employing a same power tracking component, respective drive powers of at least two of the plurality of power amplifiers of the user equipment to amplify corresponding signals of the at least two uplink carriers. Numerous other aspects are provided.

Description

TECHNIQUES AND APPARATUSES FOR IMPROVING EFFICIENCY OF POWER TRACKING IN USER EQUIPMENT

FIELD OF THE DISCLOSURE

Aspects of the present disclosure generally relate to wireless communication, and more particularly to techniques and apparatuses for improving efficiency of power tracking in user equipment (UE) .

BACKGROUND

Wireless communication systems are widely deployed to provide various telecommunication services, such as telephony, video, data, messaging, and broadcasts. Typical wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, and/or the like) . Examples of such multiple-access technologies include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, single-carrier frequency divisional multiple access (SC-FDMA) systems, and time division synchronous code division multiple access (TD-SCDMA) systems.

These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate on a municipal, a national, a regional, and even a global level. An example of a telecommunication standard is Long Term Evolution (LTE) . LTE is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by Third Generation Partnership Project (3GPP) . LTE is designed to better support mobile broadband Internet access by improving spectral efficiency, lowering costs, improving services, using new spectrum, and integrating with other open standards using OFDMA on the downlink (DL) , SC-FDMA on the uplink (UL) , and multiple-input multiple-output (MIMO) antenna technology.

SUMMARY

In some aspects, a method of wireless communication may include determining, by a user equipment, one or more power tracking parameters for a plurality of uplink carriers based at least in part on at least one of respective peak to average power ratios (PAPRs) of the plurality of uplink carriers, or respective drive power biases for amplifying the plurality of uplink carriers； and/or configuring, by the user equipment, respective drive powers of a plurality of power amplifiers of the user equipment to amplify respective signals of the plurality of uplink carriers based at least in part on the one or more power tracking parameters, wherein configuring includes configuring, by employing a same power tracking component, respective drive powers of at least two of the plurality of power amplifiers of the user equipment to amplify corresponding signals of the at least two uplink carriers.

In some aspects, a user equipment may include a memory and one or more processors operatively coupled to the memory. The one or more processors may be configured to determine one or more power tracking parameters for a plurality of uplink carriers based at least in part on at least one of respective PAPRs of the plurality of uplink carriers, or respective drive power biases for amplifying the plurality of uplink carriers； and/or configuring, by the user equipment, respective drive powers of a plurality of power amplifiers of the user equipment to amplify respective signals of the plurality of uplink carriers based at least in part on the one or more power tracking parameters, wherein configuring includes configuring, by employing a same power tracking component, respective drive powers of at least two of the plurality of power amplifiers of the user equipment to amplify corresponding signals of the at least two uplink carriers.

In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. The one or more instructions, when executed by one or more processors of a user equipment, may cause the one or more processors to determine one or more power tracking parameters for a plurality of uplink carriers based at least in part on at least one of respective PAPRs of the plurality of uplink carriers, or respective drive power biases for amplifying the plurality of uplink carriers； and/or configuring, by the user equipment, respective drive powers of a plurality of power amplifiers of the user equipment to amplify respective signals of the plurality of uplink carriers based at least in part on the one or more power tracking parameters, wherein configuring includes configuring, by employing a same power tracking component, respective drive powers of at least two of the plurality of power amplifiers of the user equipment to amplify corresponding signals of the at least two uplink carriers.

In some aspects, an apparatus for wireless communication may include means for determining one or more power tracking parameters for a plurality of uplink carriers based at least in part on at least one of respective PAPRs of the plurality of uplink carriers, or respective drive power biases for amplifying the plurality of uplink carriers； and/or mean for configuring respective drive powers of a plurality of power amplifiers of the apparatus to amplify respective signals of the plurality of uplink carriers based at least in part on the one or more power tracking parameters, wherein configuring includes configuring, by employing a same power tracking component, respective drive powers of at least two of the plurality of power amplifiers of the user equipment to amplify corresponding signals of the at least two uplink carriers.

Aspects generally include a method, apparatus, system, computer program product, non-transitory computer-readable medium, user equipment, user equipment, and processing system as substantially described herein with reference to and as illustrated by the accompanying drawings.

The foregoing has outlined rather broadly the features and technical advantages of examples according to the disclosure in order that the detailed description that follows may be better understood. Additional features and advantages will be described hereinafter. The conception 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, and not as a definition of the limits of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above-recited features of the present disclosure can be understood in detail, a more particular description, briefly summarized above, may be had by reference to aspects, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only certain typical aspects of this disclosure and are therefore not to be considered limiting of its scope, for the description may admit to other equally effective aspects. The same reference numbers in different drawings may identify the same or similar elements.

Fig. 1 is a diagram illustrating an example deployment in which multiple wireless networks have overlapping coverage, in accordance with various aspects of the present disclosure.

Fig. 2 is a diagram illustrating an example access network in an LTE network architecture, in accordance with various aspects of the present disclosure.

Fig. 3 is a diagram illustrating an example of a downlink frame structure in LTE, in accordance with various aspects of the present disclosure.

Fig. 4 is a diagram illustrating an example of an uplink frame structure in LTE, in accordance with various aspects of the present disclosure.

Fig. 5 is a diagram illustrating an example of a radio protocol architecture for a user plane and a control plane in LTE, in accordance with various aspects of the present disclosure.

Fig. 6 is a diagram illustrating example components of an evolved Node B and a UE in an access network, in accordance with various aspects of the present disclosure.

Fig. 7 is a diagram illustrating example components of a UE configured to perform power tracking (e.g., average power tracking) of multiple carriers using a single power tracking component or a reduced quantity of power tracking components, in accordance with various aspects of the present disclosure.

Fig. 8 is a diagram illustrating example components of a UE configured to perform power tracking (e.g., envelope tracking) of multiple carriers using a single power tracking component or a reduced quantity of power tracking components, in accordance with various aspects of the present disclosure.

Figs. 9A and 9B are diagrams illustrating examples of performing power tracking (e.g., average power tracking) of multiple carriers using a single power tracking component or a reduced quantity of power tracking components, in accordance with various aspects of the present disclosure.

Figs. 10A and 10B are diagrams illustrating examples of performing power tracking (e.g., envelope tracking) of multiple carriers using a single power tracking component or a reduced quantity of power tracking components, in accordance with various aspects of the present disclosure.

Fig. 11 is a flow chart of an example process performed, for example, by a user equipment, in accordance with various aspects of the present disclosure.

DETAILED DESCRIPTION

The detailed description set forth below, in connection with the appended drawings, is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for providing a thorough understanding of the various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details.

The techniques described herein may be used for one or more of various wireless communication networks such as code division multiple access (CDMA) networks, time division multiple access (TDMA) networks, frequency division multiple access (FDMA) networks, orthogonal FDMA (OFDMA) networks, single carrier FDMA (SC-FDMA) networks, or other types of networks. A CDMA network may implement a radio access technology (RAT) such as universal terrestrial radio access (UTRA) , CDMA2000, and/or the like. UTRA may include wideband CDMA (WCDMA) and/or other variants of CDMA. CDMA2000 may include Interim Standard (IS) -2000, IS-95 and IS-856 standards. IS-2000 may also be referred to as 1x radio transmission technology (1xRTT) , CDMA2000 1X, and/or the like. A TDMA network may implement a RAT such as global system for mobile communications (GSM) , enhanced data rates for GSM evolution (EDGE) , or GSM/EDGE radio access network (GERAN) . An OFDMA network may implement a RAT such as evolved UTRA (E-UTRA) , ultra mobile broadband (UMB) , Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi) , IEEE 802.16 (WiMAX) , IEEE 802.20, Flash-OFDM, and/or the like. UTRA and E-UTRA may be part of the universal mobile telecommunication system (UMTS) . 3GPP long-term evolution (LTE) and LTE-Advanced (LTE-A) are example releases of UMTS that use E-UTRA, which employs OFDMA on the downlink and SC-FDMA on the uplink. UTRA, E-UTRA, UMTS, LTE, LTE-A and 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 wireless networks and RATs mentioned above as well as other wireless networks and RATs.

Fig. 1 is a diagram illustrating an example deployment 100 in which multiple wireless networks have overlapping coverage, in accordance with various aspects of the present disclosure. However, wireless networks may not have overlapping coverage in aspects. As shown, example deployment 100 may include an evolved universal terrestrial radio access network (E-UTRAN) 105, which may include one or more evolved Node Bs (eNBs) 110, and which may communicate with other devices or networks via a serving gateway (SGW) 115 and/or a mobility management entity (MME) 120. As further shown, example deployment 100 may include a radio access network (RAN) 125, which may include one or more base stations 130, and which may communicate with other devices or networks via a mobile switching center (MSC) 135 and/or an inter-working function (IWF) 140. As further shown, example deployment 100 may include one or more user equipment (UEs) 145 capable of communicating via E-UTRAN 105 and/or RAN 125.

E-UTRAN 105 may support, for example, LTE or another type of RAT. E-UTRAN 105 may include eNBs 110 and other network entities that can support wireless communication for UEs 145. Each eNB 110 may provide communication coverage for a particular geographic area. The term “cell” may refer to a coverage area of eNB 110 and/or an eNB subsystem serving the coverage area on a specific frequency channel.

SGW 115 may communicate with E-UTRAN 105 and may perform various functions, such as packet routing and forwarding, mobility anchoring, packet buffering, initiation of network-triggered services, and/or the like. MME 120 may communicate with E-UTRAN 105 and SGW 115 and may perform various functions, such as mobility management, bearer management, distribution of paging messages, security control, authentication, gateway selection, and/or the like, for UEs 145 located within a geographic region served by MME 120 of E-UTRAN 105. The network entities in LTE are described in 3GPP TS 36.300, entitled “Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN) ； Overall description, ” which is publicly available.

RAN 125 may support, for example, GSM or another type of RAT. RAN 125 may include base stations 130 and other network entities that can support wireless communication for UEs 145. MSC 135 may communicate with RAN 125 and may perform various functions, such as voice services, routing for circuit-switched calls, and mobility management for UEs 145 located within a geographic region served by MSC 135 of RAN 125. In some aspects, IWF 140 may facilitate communication between MME 120 and MSC 135 (e.g., when E-UTRAN 105 and RAN 125 use different RATs) . Additionally, or alternatively, MME 120 may communicate directly with an MME that interfaces with RAN 125, for example, without IWF 140 (e.g., when E-UTRAN 105 and RAN 125 use a same RAT) . In some aspects, E-UTRAN 105 and RAN 125 may use the same frequency and/or the same RAT to communicate with UE 145. In some aspects, E-UTRAN 105 and RAN 125 may use different frequencies and/or RATs to communicate with UEs 145. As used herein, the term base station is not tied to any particular RAT, and may refer to an eNB (e.g., of an LTE network) or another type of base station associated with a different type of RAT.

In general, any number of wireless networks may be deployed in a given geographic area. Each wireless network may support a particular RAT and may operate on one or more frequencies. A RAT may also be referred to as a radio technology, an air interface, and/or the like. A frequency or frequency ranges may also be referred to as a carrier, a frequency channel, and/or the like. Each frequency or frequency range may support a single RAT in a given geographic area in order to avoid interference between wireless networks of different RATs.

UE 145 may be stationary or mobile and may also be referred to as a mobile station, a terminal, an access terminal, a wireless communication device, a subscriber unit, a station, and/or the like. UE 145 may be a cellular phone, a personal digital assistant (PDA) , a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, and/or the like. UE 145 may be included inside a housing 145’that houses components of UE 145, such as processor components, memory components, and/or the like.

Upon power up, UE 145 may search for wireless networks from which UE 145 can receive communication services. If UE 145 detects more than one wireless network, then a wireless network with the highest priority may be selected to serve UE 145 and may be referred to as the serving network. UE 145 may perform registration with the serving network, if necessary. UE 145 may then operate in a connected mode to actively communicate with the serving network. Alternatively, UE 145 may operate in an idle mode and camp on the serving network if active communication is not required by UE 145.

UE 145 may operate in the idle mode as follows. UE 145 may identify all frequencies/RATs on which it is able to find a “suitable” cell in a normal scenario or an “acceptable” cell in an emergency scenario, where “suitable” and “acceptable” are specified in the LTE standards. UE 145 may then camp on the frequency/RAT with the highest priority among all identified frequencies/RATs. UE 145 may remain camped on this frequency/RAT until either (i) the frequency/RAT is no longer available at a predetermined threshold or (ii) another frequency/RAT with a higher priority reaches this threshold. In some aspects, UE 145 may receive a neighbor list when operating in the idle mode, such as a neighbor list included in a system information block type 5 (SIB 5) provided by an eNB of a RAT on which UE 145 is camped. Additionally, or alternatively, UE 145 may generate a neighbor list. A neighbor list may include information identifying one or more frequencies, at which one or more RATs may be accessed, priority information associated with the one or more RATs, and/or the like.

The number and arrangement of devices and networks shown in Fig. 1 are provided as an example. In practice, there may be additional devices and/or networks, fewer devices and/or networks, different devices and/or networks, or differently arranged devices and/or networks than those shown in Fig. 1. Furthermore, two or more devices shown in Fig. 1 may be implemented within a single device, or a single device shown in Fig. 1 may be implemented as multiple, distributed devices. Additionally, or alternatively, a set of devices (e.g., one or more devices) shown in Fig. 1 may perform one or more functions described as being performed by another set of devices shown in Fig. 1.

Fig. 2 is a diagram illustrating an example access network 200 in an LTE network architecture, in accordance with various aspects of the present disclosure. As shown, access network 200 may include one or more eNBs 210 (sometimes referred to as “base stations” herein) that serve a corresponding set of cellular regions (cells) 220, one or more low power eNBs 230 that serve a corresponding set of cells 240, and a set of UEs 250.

Each eNB 210 may be assigned to a respective cell 220 and may be configured to provide an access point to a RAN. For example,

eNB

110, 210 may provide an access point for

UE

145, 250 to E-UTRAN 105 (e.g., eNB 210 may correspond to eNB 110, shown in Fig. 1) or may provide an access point for

UE

145, 250 to RAN 125 (e.g., eNB 210 may correspond to base station 130, shown in Fig. 1) . In some cases, the terms base station and eNB may be used interchangeably, and a base station, as used herein, is not tied to any particular RAT.

UE

145, 250 may correspond to UE 145, shown in Fig. 1. Fig. 2 does not illustrate a centralized controller for example access network 200, but access network 200 may use a centralized controller in some aspects. The eNBs 210 may perform radio related functions including radio bearer control, admission control, mobility control, scheduling, security, and network connectivity (e.g., to SGW 115) .

As shown in Fig. 2, one or more low power eNBs 230 may serve respective cells 240, which may overlap with one or more cells 220 served by eNBs 210. The eNBs 230 may correspond to eNB 110 associated with E-UTRAN 105 and/or base station 130 associated with RAN 125, shown in Fig. 1. A low power eNB 230 may be referred to as a remote radio head (RRH) . The low power eNB 230 may include a femto cell eNB (e.g., home eNB (HeNB) ) , a pico cell eNB, a micro cell eNB, and/or the like.

A modulation and multiple access scheme employed by access network 200 may vary depending on the particular telecommunications standard being deployed. In LTE applications, OFDM is used on the downlink (DL) and SC-FDMA is used on the uplink (UL) to support both frequency division duplexing (FDD) and time division duplexing (TDD) . The various concepts presented herein are well suited for LTE applications. However, these concepts may be readily extended to other telecommunication standards employing other modulation and multiple access techniques. By way of example, these concepts may be extended to Evolution-Data Optimized (EV-DO) or Ultra Mobile Broadband (UMB) . EV-DO and UMB are air interface standards promulgated by the 3rd Generation Partnership Project 2 (3GPP2) as part of the CDMA2000 family of standards and employs CDMA to provide broadband Internet access to mobile stations. As another example, these concepts may also be extended to UTRA employing WCDMA and other variants of CDMA (e.g., such as TD-SCDMA, GSM employing TDMA, E-UTRA, and/or the like) , UMB, IEEE 802.11 (Wi-Fi) , IEEE 802.16 (WiMAX) , IEEE 802.20, Flash-OFDM employing OFDMA, and/or the like. UTRA, E-UTRA, UMTS, LTE and GSM are described in documents from the 3GPP organization. CDMA2000 and UMB are described in documents from the 3GPP2 organization. The actual wireless communication standard and the multiple access technology employed will depend on the specific application and the overall design constraints imposed on the system.

The eNBs 210 may have multiple antennas supporting MIMO technology. The use of MIMO technology enables eNBs 210 to exploit the spatial domain to support spatial multiplexing, beamforming, and transmit diversity. Spatial multiplexing may be used to transmit different streams of data simultaneously on the same frequency. The data streams may be transmitted to a

single UE

145, 250 to increase the data rate or to multiple UEs 250 to increase the overall system capacity. This may be achieved by spatially precoding each data stream (e.g., applying a scaling of an amplitude and a phase) and then transmitting each spatially precoded stream through multiple transmit antennas on the DL. The spatially precoded data streams arrive at the UE (s) 250 with different spatial signatures, which enables each of the UE (s) 250 to recover the one or more data streams destined for that

UE

145, 250. On the UL, each

UE

145, 250 transmits a spatially precoded data stream, which enables eNBs 210 to identify the source of each spatially precoded data stream.

Spatial multiplexing is generally used when channel conditions are good. When channel conditions are less favorable, beamforming may be used to focus the transmission energy in one or more directions. This may be achieved by spatially precoding the data for transmission through multiple antennas. To achieve good coverage at the edges of the cell, a single stream beamforming transmission may be used in combination with transmit diversity.

In the detailed description that follows, various aspects of an access network will be described with reference to a MIMO system supporting OFDM on the DL. OFDM is a spread-spectrum technique that modulates data over a number of subcarriers within an OFDM symbol. The subcarriers are spaced apart at precise frequencies. The spacing provides “orthogonality” that enables a receiver to recover the data from the subcarriers. In the time domain, a guard interval (e.g., cyclic prefix) may be added to each OFDM symbol to combat inter-OFDM-symbol interference. The UL may use SC-FDMA in the form of a DFT-spread OFDM signal to compensate for high peak-to-average power ratio (PAPR) .

The number and arrangement of devices and cells shown in Fig. 2 are provided as an example. In practice, there may be additional devices and/or cells, fewer devices and/or cells, different devices and/or cells, or differently arranged devices and/or cells than those shown in Fig. 2. Furthermore, two or more devices shown in Fig. 2 may be implemented within a single device, or a single device shown in Fig. 2 may be implemented as multiple, distributed devices. Additionally, or alternatively, a set of devices (e.g., one or more devices) shown in Fig. 2 may perform one or more functions described as being performed by another set of devices shown in Fig. 2.

Fig. 3 is a diagram illustrating an example 300 of a downlink (DL) frame structure in LTE, in accordance with various aspects of the present disclosure. A frame (e.g., of 10 ms) may be divided into 10 equally sized sub-frames with indices of 0 through 9. Each sub-frame may include two consecutive time slots. A resource grid may be used to represent two time slots, each time slot including a resource block (RB) . The resource grid is divided into multiple resource elements. In LTE, a resource block includes 12 consecutive subcarriers in the frequency domain and, for a normal cyclic prefix in each OFDM symbol, 7 consecutive OFDM symbols in the time domain, or 84 resource elements. For an extended cyclic prefix, a resource block includes 6 consecutive OFDM symbols in the time domain and has 72 resource elements. Some of the resource elements, as indicated as R 310 and R 320, include DL reference signals (DL-RS) . The DL-RS include Cell-specific RS (CRS) (also sometimes called common RS) 310 and UE-specific RS (UE-RS) 320. UE-RS 320 are transmitted only on the resource blocks upon which the corresponding physical DL shared channel (PDSCH) is mapped. The number of bits carried by each resource element depends on the modulation scheme. Thus, the more resource blocks that a UE receives and the higher the modulation scheme, the higher the data rate for the UE.

In LTE, an eNB may send a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) for each cell in the eNB. The primary and secondary synchronization signals may be sent in

symbol periods

6 and 5, respectively, in each of

subframes

0 and 5 of each radio frame with the normal cyclic prefix (CP) . The synchronization signals may be used by UEs for cell detection and acquisition. The eNB may send a Physical Broadcast Channel (PBCH) in symbol periods 0 to 3 in slot 1 of subframe 0. The PBCH may carry certain system information.

The eNB may send a Physical Control Format Indicator Channel (PCFICH) in the first symbol period of each subframe. The PCFICH may convey the number of symbol periods (M) used for control channels, where M may be equal to 1, 2 or 3 and may change from subframe to subframe. M may also be equal to 4 for a small system bandwidth, e.g., with less than 10 resource blocks. The eNB may send a Physical HARQ Indicator Channel (PHICH) and a Physical Downlink Control Channel (PDCCH) in the first M symbol periods of each subframe. The PHICH may carry information to support hybrid automatic repeat request (HARQ) . The PDCCH may carry information on resource allocation for UEs and control information for downlink channels. The eNB may send a Physical Downlink Shared Channel (PDSCH) in the remaining symbol periods of each subframe. The PDSCH may carry data for UEs scheduled for data transmission on the downlink.

The eNB may send the PSS, SSS, and PBCH in the center 1.08 MHz of the system bandwidth used by the eNB. The eNB may send the PCFICH and PHICH across the entire system bandwidth in each symbol period in which these channels are sent. The eNB may send the PDCCH to groups of UEs in certain portions of the system bandwidth. The eNB may send the PDSCH to specific UEs in specific portions of the system bandwidth. The eNB may send the PSS, SSS, PBCH, PCFICH, and PHICH in a broadcast manner to all UEs, may send the PDCCH in a unicast manner to specific UEs, and may also send the PDSCH in a unicast manner to specific UEs.

A number of resource elements may be available in each symbol period. Each resource element (RE) may cover one subcarrier in one symbol period and may be used to send one modulation symbol, which may be a real or complex value. Resource elements not used for a reference signal in each symbol period may be arranged into resource element groups (REGs) . Each REG may include four resource elements in one symbol period. The PCFICH may occupy four REGs, which may be spaced approximately equally across frequency, in symbol period 0. The PHICH may occupy three REGs, which may be spread across frequency, in one or more configurable symbol periods. For example, the three REGs for the PHICH may all belong in symbol period 0 or may be spread in

symbol periods

0, 1, and 2. The PDCCH may occupy 9, 18, 36, or 72 REGs, which may be selected from the available REGs, in the first M symbol periods, for example. Only certain combinations of REGs may be allowed for the PDCCH.

A UE may know the specific REGs used for the PHICH and the PCFICH. The UE may search different combinations of REGs for the PDCCH. The number of combinations to search is typically less than the number of allowed combinations for the PDCCH. An eNB may send the PDCCH to the UE in any of the combinations that the UE will search.

As indicated above, Fig. 3 is provided as an example. Other examples are possible and may differ from what was described above in connection with Fig. 3.

Fig. 4 is a diagram illustrating an example 400 of an uplink (UL) frame structure in LTE, in accordance with various aspects of the present disclosure. The available resource blocks for the UL may be partitioned into a data section and a control section. The control section may be formed at the two edges of the system bandwidth and may have a configurable size. The resource blocks in the control section may be assigned to UEs for transmission of control information. The data section may include all resource blocks not included in the control section. The UL frame structure results in the data section including contiguous subcarriers, which may allow a single UE to be assigned all of the contiguous subcarriers in the data section.

A UE may be assigned

resource blocks

410a, 410b in the control section to transmit control information to an eNB. The UE may also be assigned

resource blocks

420a, 420b in the data section to transmit data to the eNB. The UE may transmit control information in a physical UL control channel (PUCCH) on the assigned resource blocks in the control section. The UE may transmit only data or both data and control information in a physical UL shared channel (PUSCH) on the assigned resource blocks in the data section. A UL transmission may span both slots of a subframe and may hop across frequencies.

A set of resource blocks may be used to perform initial system access and achieve UL synchronization in a physical random access channel (PRACH) 430. The PRACH 430 carries a random sequence and cannot carry any UL data/signaling. Each random access preamble occupies a bandwidth corresponding to six consecutive resource blocks. The starting frequency is specified by the network. That is, the transmission of the random access preamble is restricted to certain time and frequency resources. There is no frequency hopping for the PRACH. The PRACH attempt is carried in a single subframe (e.g., of 1 ms) or in a sequence of few contiguous subframes and a UE can make only a single PRACH attempt per frame (e.g., of 10 ms) .

As indicated above, Fig. 4 is provided as an example. Other examples are possible and may differ from what was described above in connection with Fig. 4.

Fig. 5 is a diagram illustrating an example 500 of a radio protocol architecture for a user plane and a control plane in LTE, in accordance with various aspects of the present disclosure. The radio protocol architecture for the UE and the eNB is shown with three layers: Layer 1, Layer 2, and Layer 3. Layer 1 (L1 layer) is the lowest layer and implements various physical layer signal processing functions. The L1 layer will be referred to herein as the physical layer 510. Layer 2 (L2 layer) 520 is above the physical layer 510 and is responsible for the link between the UE and eNB over the physical layer 510.

In the user plane, the L2 layer 520 includes, for example, a media access control (MAC) sublayer 530, a radio link control (RLC) sublayer 540, and a packet data convergence protocol (PDCP) sublayer 550, which are terminated at the eNB on the network side. Although not shown, the UE may have several upper layers above the L2 layer 520 including a network layer (e.g., IP layer) that is terminated at a packet data network (PDN) gateway on the network side, and an application layer that is terminated at the other end of the connection (e.g., a far end UE, a server, and/or the like) .

The PDCP sublayer 550 provides retransmission of lost data in handover. The PDCP sublayer 550 also provides header compression for upper layer data packets to reduce radio transmission overhead, security by ciphering the data packets, and handover support for UEs between eNBs. The RLC sublayer 540 provides segmentation and reassembly of upper layer data packets, retransmission of lost data packets, and reordering of data packets to compensate for out-of-order reception due to hybrid automatic repeat request (HARQ) . The MAC sublayer 530 provides multiplexing between logical and transport channels. The MAC sublayer 530 is also responsible for allocating the various radio resources (e.g., resource blocks) in one cell among the UEs. The MAC sublayer 530 is also responsible for HARQ operations.

In the control plane, the radio protocol architecture for the UE and eNB is substantially the same for the physical layer 510 and the L2 layer 520 with the exception that there is no header compression function for the control plane. The control plane also includes a radio resource control (RRC) sublayer 560 in Layer 3 (L3 layer) . The RRC sublayer 560 is responsible for obtaining radio resources (i.e., radio bearers) and for configuring the lower layers using RRC signaling between the eNB and the UE.

As indicated above, Fig. 5 is provided as an example. Other examples are possible and may differ from what was described above in connection with Fig. 5.

Fig. 6 is a diagram illustrating example components 600 of

eNB

110, 210, 230 and

UE

145, 250 in an access network, in accordance with various aspects of the present disclosure. As shown in Fig. 6,

eNB

110, 210, 230 may include a controller/processor 605, a TX processor 610, a channel estimator 615, an antenna 620, a transmitter 625TX, a receiver 625RX, an RX processor 630, and a memory 635. As further shown in Fig. 6,

UE

145, 250 may include a receiver RX, for example, of a transceiver TX/RX 640, a transmitter TX, for example, of a transceiver TX/RX 640, an antenna 645, an RX processor 650, a channel estimator 655, a controller/processor 660, a memory 665, a data sink 670, a data source 675, and a TX processor 680.

In the DL, upper layer packets from the core network are provided to controller/processor 605. The controller/processor 605 implements the functionality of the L2 layer. In the DL, the controller/processor 605 provides header compression, ciphering, packet segmentation and reordering, multiplexing between logical and transport channels, and radio resource allocations to the

UE

145, 250 based, at least in part, on various priority metrics. The controller/processor 605 is also responsible for HARQ operations, retransmission of lost packets, and signaling to the

UE

145, 250.

The TX processor 610 implements various signal processing functions for the L1 layer (e.g., physical layer) . The signal processing functions includes coding and interleaving to facilitate forward error correction (FEC) at the

UE

145, 250 and mapping to signal constellations based, at least in part, on various modulation schemes (e.g., binary phase-shift keying (BPSK) , quadrature phase-shift keying (QPSK) , M-phase-shift keying (M-PSK) , M-quadrature amplitude modulation (M-QAM) ) . The coded and modulated symbols are then split into parallel streams. Each stream is then mapped to an OFDM subcarrier, multiplexed with a reference signal (e.g., pilot) in the time and/or frequency domain, and then combined together using an Inverse Fast Fourier Transform (IFFT) to produce a physical channel carrying a time domain OFDM symbol stream. The OFDM stream is spatially precoded to produce multiple spatial streams. Channel estimates from a channel estimator 615 may be used to determine the coding and modulation scheme, as well as for spatial processing. The channel estimate may be derived from a reference signal and/or channel condition feedback transmitted by the

UE

145, 250. Each spatial stream is then provided to a different antenna 620 via a separate transmitter TX, for example, of transceiver TX/RX 625. Each such transmitter TX modulates an RF carrier with a respective spatial stream for transmission.

At the

UE

145, 250, each receiver RX, for example, of a transceiver TX/RX 640 receives a signal through its respective antenna 645. Each such receiver RX recovers information modulated onto an RF carrier and provides the information to the receiver (RX) processor 650. The RX processor 650 implements various signal processing functions of the L1 layer. The RX processor 650 performs spatial processing on the information to recover any spatial streams destined for the

UE

145, 250. If multiple spatial streams are destined for the

UE

145, 250, the spatial streams may be combined by the RX processor 650 into a single OFDM symbol stream. The RX processor 650 then converts the OFDM symbol stream from the time-domain to the frequency domain using a Fast Fourier Transform (FFT) . The frequency domain signal comprises a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols on each subcarrier, and the reference signal, are recovered and demodulated by determining the most likely signal constellation points transmitted by the

eNB

110, 210, 230. These soft decisions may be based, at least in part, on channel estimates computed by the channel estimator 655. The soft decisions are then decoded and deinterleaved to recover the data and control signals that were originally transmitted by the

eNB

110, 210, 230 on the physical channel. The data and control signals are then provided to the controller/processor 660.

The controller/processor 660 implements the L2 layer. The controller/processor 660 can be associated with a memory 665 that stores program codes and data. The memory 665 may include a non-transitory computer-readable medium. In the UL, the controller/processor 660 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover upper layer packets from the core network. The upper layer packets are then provided to a data sink 670, which represents all the protocol layers above the L2 layer. Various control signals may also be provided to the data sink 670 for L3 processing. The controller/processor 660 is also responsible for error detection using an acknowledgement (ACK) and/or negative acknowledgement (NACK) protocol to support HARQ operations.

In the UL, a data source 675 is used to provide upper layer packets to the controller/processor 660. The data source 675 represents all protocol layers above the L2 layer. Similar to the functionality described in connection with the DL transmission by the

eNB

110, 210, 230, the controller/processor 660 implements the L2 layer for the user plane and the control plane by providing header compression, ciphering, packet segmentation and reordering, and multiplexing between logical and transport channels based, at least in part, on radio resource allocations by the

eNB

110, 210, 230. The controller/processor 660 is also responsible for HARQ operations, retransmission of lost packets, and signaling to the

eNB

110, 210, 230.

Channel estimates derived by a channel estimator 655 from a reference signal or feedback transmitted by the

eNB

110, 210, 230 may be used by the TX processor 680 to select the appropriate coding and modulation schemes, and to facilitate spatial processing. The spatial streams generated by the TX processor 680 are provided to different antenna 645 via separate transmitters TX, for example, of transceivers TX/RX 640. Each transmitter TX, for example, of transceiver TX/RX 640 modulates an RF carrier with a respective spatial stream for transmission.

The UL transmission is processed at the

eNB

110, 210, 230 in a manner similar to that described in connection with the receiver function at the

UE

145, 250. Each receiver RX, for example, of transceiver TX/RX 625 receives a signal through its respective antenna 620. Each receiver RX, for example, of transceiver TX/RX 625 recovers information modulated onto an RF carrier and provides the information to a RX processor 630. The RX processor 630 may implement the L1 layer.

The controller/processor 605 implements the L2 layer. The controller/processor 605 can be associated with a memory 635 that stores program code and data. The memory 635 may be referred to as a computer-readable medium. In the UL, the control/processor 605 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover upper layer packets from the

UE

145, 250. Upper layer packets from the controller/processor 605 may be provided to the core network. The controller/processor 605 is also responsible for error detection using an ACK and/or NACK protocol to support HARQ operations.

In some aspects, one or more components of

UE

145, 250 may be included in a housing 145’, as shown in Fig 1. One or more components of

UE

145, 250 may be configured to perform power tracking of multiple carriers using a single power tracking component or a reduced quantity of power tracking components, as described in more detail elsewhere herein. For example, the controller/processor 660 and/or other processors and modules of

UE

145, 250 may perform or direct operations of, for example, process 1100 of Fig. 11, and/or other processes as described herein. In some aspects, one or more of the components shown in Fig. 6 may be employed to perform example process 1100, and/or other processes for the techniques described herein.

The number and arrangement of components shown in Fig. 6 are provided as an example. In practice, there may be additional components, fewer components, different components, or differently arranged components than those shown in Fig. 6. Furthermore, two or more components shown in Fig. 6 may be implemented within a single component, or a single component shown in Fig. 6 may be implemented as multiple, distributed components. Additionally, or alternatively, a set of components (e.g., one or more components) shown in Fig. 6 may perform one or more functions described as being performed by another set of components shown in Fig. 6.

Fig. 7 is a diagram illustrating an example of components 700 of a UE configured to perform power tracking (e.g., average power tracking) of multiple carriers using a single power tracking component or a reduced quantity of power tracking components, in accordance with various aspects of the present disclosure.

A

UE

145, 250 may transmit network traffic on one or more uplink carriers. For example, the

UE

145, 250 may be capable of performing uplink carrier aggregation (ULCA) to transmit traffic on at least two uplink carriers. The

UE

145, 250 may monitor power consumption of each of the at least two uplink carriers, and may adjust amplification of the uplink carriers based at least in part on the monitoring. For example, the

UE

145, 250 may adjust the amplification so that respective amplifiers of each of the uplink carriers operate in a linear range or an efficient range, may adjust the amplification to reduce power consumption of the

UE

145, 250, may adjust the amplification so that transmit powers of the uplink carriers are in an acceptable range, and/or the like.

Power tracking may be employed to monitor the power consumption of an uplink carrier. Average power tracking and envelope tracking are two approaches for monitoring the power consumption of an uplink carrier. In average power tracking, a

UE

145, 250 may adjust a supply voltage of a power amplifier according to an output power level of the power amplifier. For example, the

UE

145, 250 may use an average output power level of the power amplifier to determine a bias value, and may use a DC-DC converter to adjust the supply voltage according to the bias value. This bias value may be determined at a particular time granularity. As one possible example, the bias value may be determined approximately every 1 ms.

To perform envelope tracking, the

UE

145, 250 may adjust the supply voltage of the power amplifier according to a bias that is determined based at least in part on an envelope tracking signal corresponding to the output power level of the power amplifier. The envelope tracking signal may track the output power of the power amplifier over time. For example, in envelope tracking, the envelope tracking signal may track the output power more closely and/or at a tighter time granularity than the average power tracking approach. Therefore, the envelope tracking approach may be more efficient than the average power tracking approach, especially in situations where the output power fluctuates significantly (e.g., with a variation greater than a threshold) . However, average power tracking may use fewer processing resources and/or components than envelope tracking, and may be sufficient in situations where the output power does not fluctuate to a great degree (e.g., with a variation less than a threshold) .

The

UE

145, 250 may use one or more power tracking components to perform average power tracking and/or envelope tracking. For example, when performing average power tracking for multiple uplink carriers, respective power tracking components of the

UE

145, 250 may determine respective bias values to be applied for each uplink carrier. This may be costly and use a large amount of die space on an integrated circuit, particularly as a quantity of uplink carriers supported by the

UE

145, 250 increases. Similarly, when performing envelope tracking for multiple uplink carriers, respective power tracking components (e.g., DACs) of the

UE

145, 250 may generate respective envelope tracking signals for each uplink carrier. This may also be costly and use significant die space on an integrated circuit (IC) .

Methods and apparatuses, described herein, may use a reduced quantity of power tracking components (e.g., fewer than a one-to-one ratio of power tracking components to uplink carriers) to manage amplification of at least two uplink carriers. For example, a

UE

145, 250 may identify a group of uplink carriers associated with similar bias values according to an average power tracking approach, and may manage amplification of the group of uplink carriers using a single power management/tracking component. Additionally, or alternatively, the

UE

145, 250 may generate a composite envelope tracking signal for multiple uplink carriers based at least in part on respective power levels of the multiple uplink carriers using a single power tracking component. Additionally, the

UE

145, 250 may determine whether one or more uplink carriers should be managed using average power tracking or envelope tracking based at least in part on peak to average power ratios and/or power variances of the one or more uplink carriers, which conserves resources that would otherwise be used to perform envelope tracking for every uplink carrier. Thus, the

UE

145, 250 may reduce usage of power tracking components and/or power management components, which reduces cost and conserves die space of integrated circuits of the

UE

145, 250.

As indicated above, Fig. 7 is a diagram illustrating an example 700 of components of a

UE

145, 250 configured to perform power tracking (e.g., average power tracking) of multiple carriers using a single power tracking component or a reduced quantity of power tracking components. As shown in Fig. 7, the

UE

145, 250 may include transmit chains (Tx chains) 710-1 and 710-2, which may be included in a transceiver 640, as described above in connection with Fig. 6. Tx chain 710 may process a signal provided by Tx DAC 720. The signal provided by Tx DAC 720 may include an analog signal based at least in part on an uplink carrier. For example, Tx DAC 720 may convert a digital data stream to the analog signal, and may provide the analog signal to Tx chain 710. For the purpose of Fig. 7, assume that Tx chain 710-1 processes signals for a first uplink carrier, and assume that Tx chain 710-2 processes signals for a second uplink carrier.

As further shown, Tx chain 710-1 may be associated with an amplifier 730-1, and Tx chain 710-2 may be associated with an amplifier 730-2. For example, the amplifier 730-1 may amplify signals associated with the first carrier after processing by Tx chain 710-1, and the amplifier 730-2 may amplify signals associated with the second carrier after processing by Tx chain 710-2. The amplifiers 730 may amplify the signals based at least in part on a bias value provided by a power management/power tracking component 740.

The power management/power tracking component 740 may receive information identifying a power level of an uplink carrier (e.g., an average power level, a peak power level, a PAPR, and/or the like) , and may determine a bias to be applied to a supplied power or supplied voltage of an amplifier 730 that amplifies the uplink carrier. For example, the power management/power tracking component 740 may include a switched mode power supply chip, a DC-DC converter in a power supply path of the amplifier 730, a power management integrated circuit, and/or the like. After amplification by amplifiers 730-1 and 730-2, the signals of the uplink carriers are transmitted by antenna 645, as described above in connection with Fig. 6.

As shown in Fig. 7, aspects described herein are capable of amplifying signals for two or more uplink carriers using a single power management/power tracking component 740, which reduces IC die size and cost of implementing the

UE

145, 250. For example, aspects described herein may use the approach described below in connection with Figs. 9A and 9B to manage amplification of signals for multiple uplink carriers using a single power management/power tracking component 740.

In some aspects, the

UE

145, 250 may include multiple power management/power tracking components 740. In such a case, each power management/power tracking component 740 may manage amplification of one or more respective uplink carriers using the process described below in connection with Figs. 9A and 9B. Thus, by performing the processes described herein, a quantity of power management/power tracking components 740 of

UE

145, 250 is reduced relative to using a separate power management/power tracking component 740 for each uplink carrier.

As indicated above, Fig. 7 is provided as an example. Other examples are possible and may differ from what was described with respect to Fig. 7.

Fig. 8 is a diagram illustrating an example 800 of components of a

UE

145, 250 configured to perform power tracking (e.g., envelope tracking) of multiple carriers using a single power tracking component or a reduced quantity of power tracking components, in accordance with various aspects of the present disclosure.

As shown, the

UE

145, 250 may include respective Tx chains 810-1 and 810-2 of a transceiver 640, which may receive signals corresponding to uplink carriers from Tx DACs 820-1 and 820-2. Here, the Tx chain 810-1 processes signals associated with a first uplink carrier and a second uplink carrier, and the Tx chain 810-2 processes signals associated with a third uplink carrier.

As further shown, the

UE

145, 250 may include amplifiers 830-1 through 830-3. Each amplifier 830 may amplify signals associated with a respective uplink carrier. For example, amplifier 830-1 may amplify signals associated with the first uplink carrier, amplifier 830-2 may amplify signals associated with the second uplink carrier, and amplifier 830-3 may amplify signals associated with the third uplink carrier.

As further shown, the

UE

145, 250 may include power management components 840-1 and 840-2. Here, power management component 840-1 is coupled to amplifiers 830-1 and 830-2, and power management component 840-2 is coupled to amplifier 830-3. Power management component 840 may include a component capable of configuring amplifier 830 based at least in part on a bias value. For example, power management component 840 may include a switched mode power supply chip, a DC-DC converter in a power supply path of the amplifier 830, a power management integrated circuit, and/or the like. In some aspects, power management component 840 may determine whether an uplink carrier is to be managed using average power tracking or envelope tracking, as described in connection with Figs. 10A and 10B, below.

Power management component 840 may determine the bias values based at least in part on an envelope tracking envelope signal from power tracking component 850. Power tracking component 850 may include a component capable of determining an envelope tracking signal for one or more uplink carriers. For example, power tracking component 850 may include a DAC to receive digital signals associated with a plurality of uplink carriers, and to determine a composite envelope tracking signal based at least in part on power levels associated with one or more of the digital signals. In some aspects, one or more of power management component 840 and/or power tracking component 850 may be included in a modem of the UE 145, 250 (not shown) . Additionally, or alternatively, one or more of power management component 840 and/or power tracking component 850 may be implemented separately from a modem of the

UE

145, 250.

In some aspects, the composite envelope tracking signal may be determined based at least in part on an in-phase (I) and quadrature (Q) components of one or more uplink carrier signals, based at least in part on a feedback signal received from antenna 645, and/or the like) .

Some UEs may use envelope tracking for one carrier (e.g., when the UEs include a single power tracking component capable of determining an envelope for a signal) , and may use average power tracking for all other carriers (e.g., using simpler components that are not capable of determining an envelope for a signal) . This may be wasteful of power and die space. As shown in Fig. 8, the

UE

145, 250 may use a single power tracking component 850, and two power management components 840, to manage amplification of the three uplink carriers using the process described below in connection with Figs. 10A and 10B. This may use less IC die space and/or may cost less than using a separate power management component 840 and/or power tracking component 850 for each uplink carrier. By using a single power tracking component 850 to generate the composite envelope, the

UE

145, 250 reduces cost and conserves die space, and conserves power relative to using envelope tracking for at least one carrier and average power tracking for at least one other carrier.

As indicated above, Fig. 8 is provided as an example. Other examples are possible and may differ from what was described with respect to Fig. 8.

Figs. 9A and 9B are diagrams illustrating examples 900 of performing power tracking (e.g., average power tracking) of multiple carriers using a single power tracking component or a reduced quantity of power tracking components, in accordance with various aspects of the present disclosure. In some aspects, the example 900 may be performed by a UE 145, 250 (e.g., the

UE

145, 250 described in connection with Fig. 7, above) .

As shown in Fig. 9A, and by reference number 902, the

UE

145, 250 may identify a plurality of uplink carriers 1 through N for transmission of signals by the

UE

145, 250 to an

eNB

110, 210, 230. As shown by reference number 904, the

UE

145, 250 may determine respective drive powers associated with the plurality of uplink carriers. A drive power may be a power needed to amplify a signal on an uplink carrier to be transmitted at a desired signal strength. As further shown, the respective drive powers are denoted as P₁ through P_N.

As shown by reference number 906, the

UE

145, 250 may determine respective power tracking parameters (e.g., drive power biases, shown as B₁ through B_N) for the plurality of uplink carriers. A drive power bias may identify a bias to be applied to a supply power or supply voltage of an amplifier of the UE 145, 250 (e.g., amplifier 730, 830, and/or the like) so that the amplifier operates in a desired range (e.g., a linear range, a high-efficiency range, and/or the like) . For example, a power management or power tracking component of the

UE

145, 250 may be capable of providing an unbiased power supply (e.g., a battery voltage, a default voltage, and/or the like) , and may be capable of biasing the power supply to match a drive power bias so that the amplifier operates in the desired range.

In aspects, as shown by reference number 908, the

UE

145, 250 may identify one or more drive power bias values that are near the unbiased power supply value. For example, the

UE

145, 250 may identify one or more drive power bias values that are within a threshold value of the unbiased power supply value (e.g., within 5 percent, within 10 percent, within a threshold value without exceeding the unbiased power supply value, and/or the like) . As further shown, the

UE

145, 250 may amplify signals to be transmitted via one or more uplink carriers corresponding to the one or more drive power bias values according to the unbiased power supply value. For example, the

UE

145, 250 may not use the power management or power tracking device to apply bias to power supplies of amplifier (s) corresponding to the one or more drive power bias values, which conserves resources of the

UE

145, 250.

Additionally or alternatively, in some aspects, the

UE

145, 250 may identify an uplink carrier to be powered using an unbiased power supply based at least in part on historical power variation of the uplink carrier. For example, the

UE

145, 250 may store information identifying historical power variation (e.g., PAPR values, change in drive power over time, and or the like) . When the

UE

145, 250 determines that the historical power variation of the

UE

145, 250 satisfies a threshold (e.g., when the historical power variation is lower than a particular value) , the

UE

145, 250 may be powered using an unbiased power supply. In this way, the

UE

145, 250 conserves resources of a power management and/or power tracking component of the

UE

145, 250 in relation to using the power management and/or power tracking component to determine bias values for an uplink carrier that is associated with low historical power variation.

As shown in Fig. 9B, and by reference number 910, the

UE

145, 250 may identify remaining uplink carriers, of the plurality of uplink carriers, other than the one or more uplink carriers for which signals are amplified using the unbiased power supply value. As shown by reference number 912, the

UE

145, 250 may divide the remaining uplink carriers into P groups, wherein P is equal to a quantity of power tracking components included in the

UE

145, 250. For example, when the

UE

145, 250 includes two power tracking components, the

UE

145, 250 may divide the remaining uplink carriers into two groups. When the

UE

145, 250 includes a single power tracking component, the

UE

145, 250 may use a single group.

As further shown, the

UE

145, 250 may divide the remaining uplink carriers into the groups based at least in part on respective bias values of the remaining uplink carriers. For example, the

UE

145, 250 may determine a range of biases defined by a maximum bias value and a minimum bias value of the remaining uplink carriers, and may divide the range of biases into sub-ranges (e.g., equal sub-ranges) . When the remaining uplink carriers are to be divided into two groups, the

UE

145, 250 may divide the range of biases into a first sub-range between the minimum bias value and a center bias value, and a second sub-range between the center bias value and the maximum bias value. Uplink carriers with bias values in the first sub-range may be assigned to a first group, and uplink carriers with bias values in the second sub-range may be assigned to a second group.

As shown by reference number 914, the

UE

145, 250 may amplify signals for uplink carriers of each group using respective bias values. For example, when the uplink carriers are divided into a first group and a second group, a first amplifier of the

UE

145, 250 may amplify signals for uplink carriers of the first group according to a first bias value, and a second amplifier may amplify signals for uplink carriers of the second group according to a second bias value. The first bias value and the second bias value may be provided by respective power tracking components of the

UE

145, 250, which reduces a required quantity of power tracking components of the

UE

145, 250. For example, the required quantity of power tracking components may be reduced from N (the quantity of the plurality of uplink carriers) to the quantity of groups into which the uplink carriers are divided.

As further shown, in some aspects, the

UE

145, 250 may determine the respective bias values based at least in part on magnitudes of bias values (e.g., maximum bias values) of each group. For example, the

UE

145, 250 may amplify signals for a group of uplink carriers based at least in part on a highest bias value of bias values associated with uplink carriers of the group. In this way, multiple uplink carriers are grouped based at least in part on having similar bias values, and signals for those uplink carriers are amplified using a single power tracking component based at least in part on, for example, a highest bias value of the similar bias values. By amplifying using the highest bias value, signals for each uplink carrier may be amplified without exceeding a linear range of an amplifier of the

UE

145, 250, which improves performance of the amplifier. As shown by reference number 916, the

UE

145, 250 may transmit signals, on the uplink carriers, to the

eNB

110, 210, 230.

In some aspects, the

UE

145, 250 may be configured to determine a same bias value across different bands of uplink carriers. For example, the

UE

145, 250 may store mapping information that maps drive powers of uplink carriers to bias values of the uplink carriers. In aspects described herein, the mapping information may be configured such that drive powers of uplink carriers on different bands are mapped to a same bias value, or a same set of bias values. This may permit management of uplink carriers on different bands using a single power tracking component. Additionally, or alternatively, the

UE

145, 250 may store an additional characterization table for uplink carriers on a set of bands having different bias value mappings, and the additional characterization table may identify a same bias value across the set of bands, which may permit management of uplink carriers on different bands using a single power tracking component. Furthermore, the switching of uplink carriers to different power tracking components may be achieved using low-cost switches, and no switch may be required when using a single power tracking component to manage all uplink carriers of the

UE

145, 250. Using the above approach, UE power management accuracy may not be impacted and computational complexity may not be increased in comparison to traditional power management approaches, while die size and cost are reduced.

As indicated above, Figs. 9A and 9B are provided as examples. Other examples are possible and may differ from what was described with respect to Figs. 9A and 9B.

Figs. 10A and 10B are diagrams illustrating examples 1000 of performing power tracking (e.g., envelope tracking) of multiple carriers using a single power tracking component or a reduced quantity of power tracking components, in accordance with various aspects of the present disclosure. The example 1000 may be performed by a UE 145, 250 (e.g., the

UE

145, 250 described in connection with Fig. 8, above) .

As shown in Fig. 10A, and by reference number 1002, the

UE

145, 250 may identify a plurality of uplink carriers 1 through N for transmission by the

UE

145, 250 to an

eNB

110, 210, 230. As shown by reference number 1004, the

UE

145, 250 may determine respective PAPRs of the plurality of uplink carriers (e.g., PAPR₁ through PAPR_N) . PAPR may be an indicator of variance between a peak power value of an uplink carrier and an average power value of the uplink carrier. An uplink carrier with a high PAPR may be more efficiently powered using envelope tracking (e.g., since a required drive power bias may change frequently when PAPR is high) , whereas an uplink carrier with a low PAPR may be more efficiently powered using average power tracking (e.g., since more complex components may be required to perform envelope tracking than to perform average power tracking) .

As shown by reference number 1006, the

UE

145, 250 may determine respective average powers (e.g., respective average drive powers, shown as P₁ through P_N) of the uplink carriers. The

UE

145, 250 may use the respective drive powers to group the uplink carriers so that uplink carriers with similar drive powers are managed by a single power tracking component, as described in more detail below.

As shown by reference number 1008, the

UE

145, 250 may identify one or more first carriers, of the plurality of uplink carriers, with PAPR values that do not satisfy a threshold (e.g., with PAPR values that are below a value PAPR_THRESH) . In some aspects, the threshold may be based at least in part on a relative efficiency of using average power tracking or envelope tracking to manage amplification of an uplink carrier. For example, when a PAPR of an uplink carrier does not satisfy the threshold, the uplink carrier may be more efficiently managed using average power tracking. When the PAPR of the uplink carrier satisfies the threshold, the uplink carrier may be more efficiently managed using envelope tracking.

As shown by reference number 1010, the

UE

145, 250 may amplify signals for the one or more first carriers using average power tracking. For example, in some aspects, the

UE

145, 250 may perform the approach described in connection with Figs. 9A and 9B, above, to amplify signals for the one or more first carriers, which may reduce a quantity of power tracking components needed to manage amplification of the one or more first carriers.

As shown by reference number 1012, the

UE

145, 250 may group second carriers, of the remaining carriers other than the one or more first carriers, that have similar average power values to each other. For example, the

UE

145, 250 may assign the second carriers to one or more groups based on the average power values of the second carriers. In some aspects, the

UE

145, 250 may determine the one or more groups using an approach similar to the approach used to determine the groups described in connection with reference number 912 of Fig. 9B, above. For example, the

UE

145, 250 may determine respective sub-ranges of a range of average power values, and may assign the first carriers to groups corresponding to the respective sub-ranges based at least in part on average power values of the first carriers. By grouping the second carriers based at least in part on similarity of average power values of the second carriers, the

UE

145, 250 can manage a group of carriers using a single power tracking component, which conserves cost and die size.

As shown in Fig. 10B, and by reference number 1014, the UE 145, 250 (e.g., a power tracking component of the UE 145, 250) may determine a composite envelope tracking envelope for the group of the second carriers. The composite envelope tracking envelope may identify a maximum envelope value (e.g., a highest drive power value) of the group of second carriers at each point in time. By providing the group of second carriers to the power tracking component as input to determine the combined power tracking envelope, the

UE

145, 250 conserves resources and uses a lesser quantity of power tracking components than if each second carrier was provided to a different power tracking component.

As shown by reference number 1016, the

UE

145, 250 may determine a power tracking parameter (e.g., a drive power bias value) based at least in part on the combined envelope tracking envelope. For example, the UE 145, 250 (e.g., the power tracking component) may generate a signal corresponding to the composite envelope tracking envelope. The power tracking component, or a power management component of the

UE

145, 250, may determine a drive power bias value based at least in part on the signal. For example, the

UE

145, 250 may store information mapping drive power bias values to signal values, and may determine the drive power bias value based at least in part on a value of the signal.

As shown by reference number 1018, the

UE

145, 250 may amplify signals for the second carriers based at least in part on the drive power bias value. For example, a power tracking component or power management component of the

UE

145, 250 may adjust supply powers or voltages of each amplifier associated with the second carriers according to the drive power bias value. In this way, the power tracking component determines a composite envelope for multiple, different uplink carriers, and configures multiple, different amplifiers to amplify based on the composite envelope. Thus, hardware resources of the

UE

145, 250 are conserved (e.g., resources of power tracking components and/or power management components of the UE 145, 250) . Furthermore, aspects described herein may enable management of an increasing quantity of uplink carriers using a constant quantity of power tracking components. As shown by reference number 1020, the

UE

145, 250 may transmit signals, on the uplink carriers, to the

eNB

110, 210, 230.

While Figs. 10A and 10B are described primarily in the context of amplifying a group of second carriers, the approach described in Figs. 10A and 10B is equally applicable for multiple, different groups of carriers. For example, each group of carriers may have similar average power values, may be provided to a respective power tracking component that generates a respective composite envelope tracking envelope, and may be amplified according to the respective composite envelope tracking envelope.

The above approach may be used in a

UE

145, 250 where the composite envelope is determined using in-phase (I) and quadrature (Q) signals corresponding to one or more carriers at a modem of the UE 145, 250 (e.g., before amplification) , as well as in a

UE

145, 250 where the composite envelope is determined using a feedback receiver-based sampling of a transmission signal of an antenna of the

UE

145, 250. In the first case using one or more IQ signals (e.g., using IQ signals of a first carrier and IQ signals of a second carrier) , the modem of the

UE

145, 250 may determine a maximum value of such IQ signals at each point in time, and may provide the maximum value to a DAC, which may generate the composite envelope tracking signal. In aspects, the

UE

145, 250 may compare an IQ signal of a first carrier and an IQ signal of a second carrier to determine a maximum IQ signal. In the second case (e.g., using the feedback receiver-based sampling) , the

UE

145, 250 may provide feedback regarding multiple uplink carriers to a processing block (e.g., of a modem, a power tracking component, and/or the like) . The processing block may generate a composite envelope signal using the feedback regarding the multiple uplink carriers and using respective reference signals for the multiple uplink carriers.

In some aspects, the

UE

145, 250 may apply a power backoff to a plurality of uplink carriers. For example, the

UE

145, 250 may compute and apply an IQ signal backoff in a baseband domain, which may improve power accuracy that would otherwise be diminished by a feedback-received based sampling of the plurality of uplink carriers. Thus, accuracy of power management of the

UE

145, 250 may be preserved, while cost and die size of power tracking components of the

UE

145, 250 are reduced.

As indicated above, Figs. 10A and 10B are provided as examples. Other examples are possible and may differ from what was described with respect to Figs. 10A and 10B.

Fig. 11 is a diagram illustrating an example process 1100 performed, for example, by a user equipment, in accordance with various aspects of the present disclosure. Example process 1100 is an example where a user equipment (e.g., UE 145, 250) performs power tracking of multiple carriers using a single power tracking component or a reduced quantity of power tracking components.

As shown in Fig. 11, in some aspects, process 1100 may include determining one or more power tracking parameters for a plurality of uplink carriers based at least in part on at least one of respective peak to average power ratios (PAPRs) of the plurality of uplink carriers, or respective drive power biases for amplifying the plurality of uplink carriers (block 1110) . For example, the user equipment may determine respective power tracking parameters (e.g., a drive power bias, a composite envelope tracking envelope, and/or the like) for a plurality of uplink carriers. The user equipment may determine the respective power tracking parameters based at least in part on one or more of respective PAPRs of the plurality of uplink carriers, respective drive power biases for amplifying the plurality of uplink carriers, and/or the like.

As shown in Fig. 11, in some aspects, process 1100 may include configuring respective drive powers of a plurality of power amplifiers to amplify respective signals of the plurality of uplink carriers based at least in part on the one or more power tracking parameters, wherein configuring includes configuring by employing a same power tracking component respective drive powers of at least two of the plurality of power amplifiers to amplify corresponding signals of the at least two uplink carriers (block 1120) . For example, a single power tracking component of the user equipment may configure respective drive powers of at least two power amplifiers, of a plurality of power amplifiers of the user equipment, to amplify corresponding signals of at least two uplink carriers. The at least two uplink carriers may be included in the plurality of uplink carriers, and the plurality of uplink carriers may be amplified by the user equipment according to respective drive power of the plurality of uplink carriers. For example, amplification of the plurality of uplink carriers may be managed by the single power tracking component, or may be managed by another power tracking component.

In some aspects, the user equipment may determine the one or more power tracking parameters further based at least in part on respective power variations of the plurality of uplink carriers. In some aspects, the user equipment may configure the respective drive powers of the at least two of the plurality of power amplifiers using a maximum drive power bias of the respective drive power biases, the one or more power tracking parameters being based at least in part on the maximum drive power bias.

In some aspects, the user equipment may determine that a drive power bias for amplifying a particular uplink carrier, of the plurality of uplink carriers, is within a threshold value of an unbiased power supply value of a particular power amplifier corresponding to the particular uplink carrier. The user equipment may amplify signals of the particular uplink carrier based at least in part on the unbiased power supply value.

In some aspects, the power tracking component may be a first power tracking component, the power tracking parameter may be a first power tracking parameter, and the user equipment may have a second power tracking component. The user equipment may configure, by the first power tracking component, drive powers of first power amplifiers, of the plurality of power amplifiers, corresponding to a first group of uplink carriers based at least in part on the first power tracking parameter. The user equipment may configure, by the second power management component, drive powers of second power amplifiers, of the plurality of power amplifiers, corresponding to a second group of uplink carriers based at least in part on a second power tracking parameter.

In some aspects, the user equipment may identify a first group of uplink carriers, of the plurality of uplink carriers, associated with PAPRs that do not satisfy a threshold, and may identify a second group of uplink carriers, of the plurality of uplink carriers, associated with PAPRs that satisfy the threshold. The user equipment may configure drive powers of power amplifiers of the first group of uplink carriers according to an average power tracking approach, and may configure drive powers of the power amplifiers of the second group of uplink carriers according to an envelope tracking approach. In some aspects, the user equipment may identify the second group of uplink carriers based at least in part on the second group of uplink carriers having average power values that are within a threshold value of each other.

In some aspects, the one or more power tracking parameters may be based at least in part on a combined envelope tracking envelope of each uplink carrier of the plurality of uplink carriers. In some aspects, the combined envelope tracking envelope may be based on a comparison of digital samples corresponding to the plurality of uplink carriers.

In some aspects, the one or more power tracking parameters may be determined by a single digital analog converter of the user equipment. In some aspects, the power tracking may include at least one of envelope tracking or average power tracking. In some aspects, the same power tracking component includes a single digital-to-analog convertor or a single power amplifier power biasing component.

Although Fig. 11 shows example blocks of process 1100, in some aspects, process 1100 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in Fig. 11. Additionally, or alternatively, two or more of the blocks of process 1100 may be performed in parallel.

The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit the aspects to the precise form disclosed. Modifications and variations are possible in light of the above disclosure or may be acquired from practice of the aspects.

As used herein, the term component is intended to be broadly construed as hardware, firmware, or a combination of hardware and software. As used herein, a processor is implemented in hardware, firmware, or a combination of hardware and software.

Some aspects are described herein in connection with thresholds. As used herein, satisfying a threshold may refer to a value being greater than the threshold, greater than or equal to the threshold, less than the threshold, less than or equal to the threshold, equal to the threshold, not equal to the threshold, and/or the like.

It will be apparent that systems and/or methods, described herein, may be implemented in different forms of hardware, firmware, or a combination of hardware and software. The actual specialized control hardware or software code used to implement these systems and/or methods is not limiting of the aspects. Thus, the operation and behavior of the systems and/or methods were described herein without reference to specific software code—it being understood that software and hardware can be designed to implement the systems and/or methods based, at least in part, on the description herein.

Even though particular combinations of features are recited in the claims and/or disclosed in the specification, these combinations are not intended to limit the disclosure of possible aspects. In fact, many of these features may be combined in ways not specifically recited in the claims and/or disclosed in the specification. Although each dependent claim listed below may directly depend on only one claim, the disclosure of possible aspects includes each dependent claim in combination with every other claim in the claim set. A phrase referring to “at least one of” a list of items refers to any combination of those items, including single members. As an example, “at least one of: a, b, or c” is intended to cover a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combination with multiples of the same element (e.g., a-a, a-a-a, a-a-b, a-a-c, a-b-b, a-c-c, b-b, b-b-b, b-b-c, c-c, and c-c-c or any other ordering of a, b, and c) .

No element, act, or instruction used herein should be construed as critical or essential unless explicitly described as such. Also, as used herein, the articles “a” and “an” are intended to include one or more items, and may be used interchangeably with “one or more. ” Furthermore, as used herein, the terms “set” and “group” are intended to include one or more items (e.g., related items, unrelated items, a combination of related and unrelated items, and/or the like) , and may be used interchangeably with “one or more. ” Where only one item is intended, the term “one” or similar language is used. Also, as used herein, the terms “has, ” “have, ” “having, ” and/or the like are intended to be open-ended terms. Further, the phrase “based on” is intended to mean “based, at least in part, on” unless explicitly stated otherwise.

Claims

A method of wireless communication, comprising:

determining, by a user equipment, one or more power tracking parameters for a plurality of uplink carriers based at least in part on at least one of:

respective peak to average power ratios (PAPRs) of the plurality of uplink carriers, or

respective drive power biases for amplifying the plurality of uplink carriers； and

configuring, by the user equipment, respective drive powers of a plurality of power amplifiers of the user equipment to amplify respective signals of the plurality of uplink carriers based at least in part on the one or more power tracking parameters, wherein configuring includes configuring, by employing a same power tracking component, respective drive powers of at least two of the plurality of power amplifiers of the user equipment to amplify corresponding signals of the at least two uplink carriers.
The method of claim 1, wherein determining includes determining further based at least in part on respective power variations of the plurality of uplink carriers.
The method of claim 1, wherein configuring the respective drive powers of the at least two of the plurality of power amplifiers includes:

configuring the respective drive powers of the at least two of the plurality of power amplifiers using a maximum drive power bias of the respective drive power biases,

the one or more power tracking parameters being based at least in part on the maximum drive power bias.
The method of claim 1, further comprising:

determining that a drive power bias for amplifying a particular uplink carrier, of the plurality of uplink carriers, is within a threshold value of an unbiased power supply value of a particular power amplifier corresponding to the particular uplink carrier； and

wherein configuring the respective drive powers of the plurality of power amplifiers includes amplifying signals of the particular uplink carrier based at least in part on the unbiased power supply value.
The method of claim 1, wherein the power tracking component is a first power tracking component, the power tracking parameter is a first power tracking parameter, and the user equipment has a second power tracking component； and

wherein configuring the respective drive powers includes:

configuring, by the first power tracking component, drive powers of first power amplifiers, of the plurality of power amplifiers, corresponding to a first group of uplink carriers based at least in part on the first power tracking parameter； and

configuring, by the second power management component, drive powers of second power amplifiers, of the plurality of power amplifiers, corresponding to a second group of uplink carriers based at least in part on a second power tracking parameter.
The method of claim 1, further comprising:

identifying a first group of uplink carriers, of the plurality of uplink carriers, associated with PAPRs that do not satisfy a threshold； and

identifying a second group of uplink carriers, of the plurality of uplink carriers, associated with PAPRs that satisfy the threshold； and

wherein configuring the respective drive powers of the plurality of power amplifiers comprises:

configuring drive powers of power amplifiers of the first group of uplink carriers according to an average power tracking approach； and

configuring drive powers of the power amplifiers of the second group of uplink carriers according to an envelope tracking approach.
The method of claim 6, wherein identifying the second group of uplink carriers comprises:

identifying the second group of uplink carriers based at least in part on the second group of uplink carriers having average power values that are within a threshold value of each other.
The method of claim 1, wherein the one or more power tracking parameters are based at least in part on a combined envelope tracking envelope of each uplink carrier of the plurality of uplink carriers.
The method of claim 8, wherein the combined envelope tracking envelope is based on a comparison of digital samples corresponding to the plurality of uplink carriers.
The method of claim 8, wherein the one or more power tracking parameters are determined by a single digital analog converter of the user equipment.
The method of claim 1, wherein the power tracking includes at least one of envelope tracking or average power tracking.
The method of claim 1, wherein the same power tracking component includes a single digital-to-analog convertor or a single power amplifier power biasing component.
A user equipment, comprising:

a memory； and

one or more processors, operatively configured to the memory, the one or more processors being configured to:

determine one or more power tracking parameters for a plurality of uplink carriers based at least in part on at least one of:

respective peak to average power ratios (PAPRs) of the plurality of uplink carriers, or

respective drive power biases for amplifying the plurality of uplink carriers； and

configure respective drive powers of a plurality of power amplifiers of the user equipment to amplify respective signals of the plurality of uplink carriers based at least in part on the one or more power tracking parameters, wherein configuring includes configuring, by employing a same power tracking component, respective drive powers of at least two of the plurality of power amplifiers of the user equipment to amplify corresponding signals of the at least two uplink carriers.
The user equipment of claim 13, wherein the one or more processors, when determining the one or more power tracking parameters, are configured to:

determine the one or more power tracking parameters further based at least in part on respective power variations of the plurality of uplink carriers.
The user equipment of claim 13, wherein the one or more processors, when configuring the respective drive powers of the at least two of the plurality of power amplifiers, are configured to:

configure the respective drive powers of the at least two of the plurality of power amplifiers using a maximum drive power bias of the respective drive power biases,

the one or more power tracking parameters being based at least in part on the maximum drive power bias.
The user equipment of claim 13, wherein the one or more processors are further configured to:

determine that a drive power bias for amplifying a particular uplink carrier, of the plurality of uplink carriers, is within a threshold value of an unbiased power supply value of a particular power amplifier corresponding to the particular uplink carrier； and

wherein the one or more processors, when performing the configuring the respective drive powers of the plurality of power amplifiers, are configured to:

amplify signals of the particular uplink carrier based at least in part on the unbiased power supply value.
The user equipment of claim 13, wherein the power tracking component is a first power tracking component, the power tracking parameter is a first power tracking parameter, and the user equipment has a second power tracking component； and

wherein the one or more processors, when configuring the respective drive powers, are configured to:

configure, by the first power tracking component, drive powers of first power amplifiers, of the plurality of power amplifiers, corresponding to a first group of uplink carriers based at least in part on the first power tracking parameter； and

configure, by the second power management component, drive powers of second power amplifiers, of the plurality of power amplifiers, corresponding to a second group of uplink carriers based at least in part on a second power tracking parameter.
The user equipment of claim 13, wherein the one or more processors are further configured to:

identify a first group of uplink carriers, of the plurality of uplink carriers, associated with PAPRs that do not satisfy a threshold； and

identify a second group of uplink carriers, of the plurality of uplink carriers, associated with PAPRs that satisfy the threshold； and

wherein the one or more processors, when configuring the respective drive powers of the plurality of power amplifiers, are configured to:

configure drive powers of power amplifiers of the first group of uplink carriers according to an average power tracking approach； and

configure drive powers of the power amplifiers of the second group of uplink carriers according to an envelope tracking approach.
The user equipment of claim 13, wherein the one or more power tracking parameters are based at least in part on a combined envelope tracking envelope of each uplink carrier of the plurality of uplink carriers.
The user equipment of claim 13, wherein the same power tracking component includes a single digital-to-analog convertor or a single power amplifier power biasing component.
A non-transitory computer-readable medium storing instructions, the instructions comprising:

one or more instructions that, when executed by one or more processors of a user equipment, cause the one or more processors to:

determine one or more power tracking parameters for a plurality of uplink carriers based at least in part on at least one of:

respective peak to average power ratios (PAPRs) of the plurality of uplink carriers, or

respective drive power biases for amplifying the plurality of uplink carriers； and

configure respective drive powers of a plurality of power amplifiers of the user equipment to amplify respective signals of the plurality of uplink carriers based at least in part on the one or more power tracking parameters, wherein configuring includes configuring, by employing a same power tracking component, respective drive powers of at least two of the plurality of power amplifiers of the user equipment to amplify corresponding signals of the at least two uplink carriers.
The non-transitory computer-readable medium of claim 21, wherein the one or more instructions, that cause the one or more processors to determine the one or more power tracking parameters, cause the one or more processors to:

determine the one or more power tracking parameters further based at least in part on respective power variations of the plurality of uplink carriers.
The non-transitory computer-readable medium of claim 21, wherein the one or more instructions, that cause the one or more processors to configure the respective drive powers of the at least two of the plurality of power amplifiers, cause the one or more processors to:

configure the respective drive powers of the at least two of the plurality of power amplifiers using a maximum drive power bias of the respective drive power biases,

the one or more power tracking parameters being based at least in part on the maximum drive power bias.
The non-transitory computer-readable medium of claim 21, wherein the one or more instructions, when executed by the one or more processors, cause the one or more processors to:

determine that a drive power bias for amplifying a particular uplink carrier, of the plurality of uplink carriers, is within a threshold value of an unbiased power supply value of a particular power amplifier corresponding to the particular uplink carrier； and

wherein the one or more instructions, that cause the one or more processors to perform the configuring the respective drive powers of the plurality of power amplifiers, cause the one or more processors to:

amplify signals of the particular uplink carrier based at least in part on the unbiased power supply value.
The non-transitory computer-readable medium of claim 21, wherein the power tracking component is a first power tracking component, the power tracking parameter is a first power tracking parameter, and the user equipment has a second power tracking component； and

wherein the one or more instructions, that cause the one or more processors to configure the respective drive powers, cause the one or more processors to:

configure, by the first power tracking component, drive powers of first power amplifiers, of the plurality of power amplifiers, corresponding to a first group of uplink carriers based at least in part on the first power tracking parameter； and

configure, by the second power management component, drive powers of second power amplifiers, of the plurality of power amplifiers, corresponding to a second group of uplink carriers based at least in part on a second power tracking parameter.
The non-transitory computer-readable medium of claim 21, wherein the one or more instructions, when executed by the one or more processors, cause the one or more processors to:

identify a first group of uplink carriers, of the plurality of uplink carriers, associated with PAPRs that do not satisfy a threshold； and

identify a second group of uplink carriers, of the plurality of uplink carriers, associated with PAPRs that satisfy the threshold； and

wherein the one or more processors, when configuring the respective drive powers of the plurality of power amplifiers, are configured to:

configure drive powers of power amplifiers of the first group of uplink carriers according to an average power tracking approach； and

configure drive powers of the power amplifiers of the second group of uplink carriers according to an envelope tracking approach.
The non-transitory computer-readable medium of claim 21, wherein the same power tracking component includes a single digital-to-analog convertor or a single power amplifier power biasing component.
An apparatus for wireless communication, comprising:

means for determining one or more power tracking parameters for a plurality of uplink carriers based at least in part on at least one of:

respective peak to average power ratios (PAPRs) of the plurality of uplink carriers, or

respective drive power biases for amplifying the plurality of uplink carriers； and

means for configuring respective drive powers of a plurality of power amplifiers of the apparatus to amplify respective signals of the plurality of uplink carriers based at least in part on the one or more power tracking parameters, wherein configuring includes configuring, by employing a same power tracking component, respective drive powers of at least two of the plurality of power amplifiers of the apparatus to amplify corresponding signals of the at least two uplink carriers.
The apparatus of claim 28, wherein the means for determining includes means for determining further based at least in part on respective power variations of the plurality of uplink carriers.
The apparatus of claim 28, wherein the means for configuring the respective drive powers of the at least two of the plurality of power amplifiers includes:

means for configuring the respective drive powers of the at least two of the plurality of power amplifiers using a maximum drive power bias of the respective drive power biases,

the one or more power tracking parameters being based at least in part on the maximum drive power bias.