Envelope tracking system, mobile device, and method of envelope tracking

Abstract

To provide a multi-level envelope tracking system that can provide increased efficiency over a wide range of signal powers.SOLUTION: An envelope tracking system 100 includes a multi-level supply (MLS) DC / DC converter 72 that outputs multiple regulated voltages, an MLS modulator 81 that controls selection of the regulated voltages over time on the basis of an envelope signal corresponding to the envelope of a radio frequency (RF) signal amplified by a power amplifier 71, and a modulator output filter 91 coupled between the output of the MLS modulator and the power amplifier supply voltage. The envelope tracking system further includes a switching point adaptation circuit 75 configured to control the voltage levels of the regulated voltages output by the MLS DC / DC converter based on the power level of the RF signal.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] Embodiments of the present invention relate to electronic systems, and more particularly to radio frequency (RF) electronic devices. This invention relates to a power amplifier. [Background technology]

[0002] In RF communications systems, a device is used to amplify an RF signal for transmission via an antenna. Power amplifiers are used to extend battery life and / or provide adequate transmit power levels. It is important to manage the power of RF signal transmission to achieve this.

[0003] Examples of RF communication systems that have one or more power amplifiers include mobile phones, tablets, base stations, and the like. Stations, network access points, customer premises equipment (CPE), laptops, and web This includes, but is not limited to, wireless electronic devices. For example, cellular standards, wireless local area networks, Wireless LAN (WLAN) standard, and / or any other suitable communication standard. In wireless devices that receive signals, power amplifiers are often used to amplify the RF signals. RF signals can be used, for example, for 5th generation (5G) communications in Frequency Range 1 (FR1). For example, the range of about 410MHz to about 7.125GHz, about 30kHz to 300GHz It may have frequencies in the range z. Summary of the Invention

[0004] In certain embodiments, the present disclosure relates to an envelope tracking system. is configured to amplify a radio frequency signal and to receive power from a power amplifier supply voltage. and a power amplifier for controlling said power amplifier based on an envelope signal corresponding to an envelope of said radio frequency signal. and an envelope tracker configured to generate a power amplifier supply voltage. a DC / DC converter configured to output a number of regulated voltages; a modulator configured to control a power amplifier supply voltage based on the radio frequency and envelope signals; At least one of the adjusted voltages is adjusted based on a power level of the wavenumber signal. and a switching point adaptation circuit configured to control a voltage level of the read voltage.

[0005] In some embodiments, the switching point adaptation circuitry is and configured to control a voltage level of each of the plurality of regulated voltages based on the input level. can be.

[0006] In various embodiments, the switching point adaptation circuitry may be and estimating a power level of the radio frequency signal based on the signal power value of at least one of the symbols. According to a number of embodiments, the signal power value is calculated based on the transmit frame. In some embodiments, the signal power value denotes the peak power for a transmission frame or symbol. The switching point adaptation circuit further comprises a plurality of desired voltages associated with the signal power values. According to certain embodiments, the switch includes a voltage estimation circuit configured to estimate a level of the switch. The switching point adaptation circuit further comprises a desired voltage level adjusting circuit for adjusting a corresponding one of a plurality of desired voltage levels. The DC / DC converter is controlled to output multiple regulated voltages, each with a different voltage level. The programming circuitry is configured to control the

[0007] In some embodiments, the envelope tracking system further comprises two or more radio frequency signals. and the envelope tracker includes two or more power amplifiers configured to amplify a plurality of regulated A supply voltage for a corresponding one of the two or more power amplifiers receiving the voltage. The modulator includes two or more modulators each configured to provide a modulation that generates a certain number of According to an embodiment, the switching point adaptation circuitry is adapted to adjust a maximum power level of two or more radio frequency signals. The input signal is configured to control a voltage level based on the input signal.

[0008] In some embodiments, a DC / DC converter is provided to receive the battery voltage and generating a plurality of regulated voltages based on providing a DC / DC conversion of the battery voltage; , is composed.

[0009] In some embodiments, the plurality of regulated voltages each have a different voltage level. It has a

[0010] In various embodiments, the envelope tracker further comprises a plurality of regulated voltages connected to ground. The input / output terminals include a plurality of decoupling capacitors coupled between corresponding ones of the input / output terminals.

[0011] In a number of embodiments, the modulators each have a modulator output voltage and the plurality of regulated The supply voltage includes a plurality of switches coupled between the supply voltage and a corresponding regulated voltage.

[0012] In some embodiments, the envelope tracker further comprises a modulator output and a power amplifier supply a modulator output filter connected between the modulator output and the voltage, the modulator output filter comprising at least Each includes one series inductor and at least one shunt capacitor.

[0013] In certain embodiments, the present disclosure relates to a mobile device. a transceiver configured to generate a radio frequency transmit signal; and US20130233633A1 - Front end circuit including a power amplifier configured to receive power from a power amplifier supply voltage - Google Patents and determining a power amplifier supply voltage based on an envelope signal corresponding to an envelope of the radio frequency transmission signal. and a power management circuit including an envelope tracker configured to generate a voltage. a DC / DC converter configured to output a plurality of regulated voltages; a modulator configured to control a power amplifier supply voltage based on the input voltage and the envelope signal; at least one of the plurality of adjusted voltages based on a power level of a line frequency transmission signal; a switching point adaptation circuit configured to control a voltage level of the regulated voltage of the Includes.

[0014] In various embodiments, the switching point adaptation circuitry adjusts the power of the radio frequency transmission signal. and configured to control a voltage level of each of the plurality of regulated voltages based on the input level. can be.

[0015] In some embodiments, the switching point adaptation circuitry may a power level of the radio frequency transmission signal based on the signal power value for at least one of the received symbols; According to a number of embodiments, the signal power includes a power estimation circuit configured to estimate a signal power. The power value indicates the average power for a transmitted frame or symbol. The signal power value indicates the peak power for a transmission frame or symbol. According to an embodiment, the switching point adaptation circuit further comprises a plurality of In accordance with a number of embodiments, the present invention includes a voltage estimation circuit configured to estimate a desired voltage level of the the switching point adaptation circuit further comprises: The DC / DC converter is designed to output multiple regulated voltages, each with one desired voltage level. A programming circuit configured to control the transducer is included.

[0016] In some embodiments, the mobile device further comprises two or more radio frequency transmission signals. and an envelope tracker configured to amplify the plurality of conditioned power amplifiers. a supply voltage for a corresponding one of the two or more power amplifiers in response to the voltage The modulator may include two or more modulators, each configured to provide the modulation that is generated. According to the present invention, a switching point matching circuit is provided for adjusting the maximum power level of two or more radio frequency transmission signals. The input signal is configured to control a voltage level based on the input signal.

[0017] In some embodiments, a DC / DC converter is provided to receive the battery voltage and generating a plurality of regulated voltages based on providing a DC / DC conversion of the battery voltage; , is composed.

[0018] In various embodiments, the multiple regulated voltages each have a different voltage level. do.

[0019] In some embodiments, the envelope tracker further comprises a plurality of regulated voltages connected to ground. and a plurality of decoupling capacitors coupled between the corresponding regulated voltages of the first and second inputs.

[0020] In some embodiments, the modulators each have a modulator output voltage and the plurality of adjustments. The power supply includes a plurality of switches coupled between the corresponding regulated voltages of the power supply and the corresponding regulated voltages.

[0021] In various embodiments, the portable device further comprises a modulator output and a power amplifier supply voltage. and a modulator output filter connected between the at least one It includes a series inductor and at least one shunt capacitor.

[0022] In certain embodiments, the present disclosure relates to a method of envelope tracking, the method comprising: and amplifying the radio frequency signal using a power amplifier supply voltage. and outputting a plurality of regulated voltages from the DC / DC converter. a modulator is used to control a power amplifier voltage based on the plurality of regulated voltages and an envelope signal; and controlling the envelope signal, the envelope signal corresponding to an envelope of the radio frequency signal. further comprising: determining at least one of the plurality of regulated voltages based on a power level of the radio frequency signal; Controlling the voltage level of one of the regulated voltages.

[0023] In various embodiments, the method further comprises: The method includes controlling each of the regulated voltages.

[0024] In some embodiments, the method further comprises: and estimating a power level of the radio frequency signal based on the signal power values ​​for either one of the signals. According to a number of embodiments, the signal power value is the average for a transmission frame or symbol. According to some embodiments, the signal power value indicates the power of a transmission frame or symbol. According to various embodiments, the method further comprises: According to some embodiments, the method includes estimating a plurality of desired voltage levels to be applied. The method further comprises: each of the desired voltage levels comprising a corresponding one of the plurality of desired voltage levels. Controlling the DC / DC converter to output a plurality of regulated voltages.

[0025] In some embodiments, the method further comprises providing a DC / DC conversion of the battery voltage. generating a plurality of regulated voltages based on the

[0026] In various embodiments, the multiple regulated voltages each have a different voltage level. do. [Brief description of the drawings]

[0027] [Figure 1] FIG. 2 is a schematic diagram of a mobile device according to an embodiment. [Diagram 2] 1 is a schematic diagram of an envelope tracking system for a power amplifier according to one embodiment; [Figure 3A] FIG. 2 is a schematic diagram of an envelope tracking system according to another embodiment. [Figure 3B] FIG. 2 is a schematic diagram of an envelope tracking system according to another embodiment. [Figure 4] 1 is a voltage versus time graph of five example signal waveforms at different power levels. [Figure 5A] 1 is a graph of an example of a power amplifier supply voltage versus input power. [Figure 5B] 1 is a graph of an example of power added efficiency (PAE) versus output power for various example signal waveforms. [Figure 6A] 11 is another example graph of power amplifier supply voltage versus input power. [Figure 6B] 11 is another example graph of PAE versus output power for various example signal waveforms. [Figure 7] FIG. 2 is a schematic diagram of a mobile device according to another embodiment. [Figure 8]FIG. 1 is a schematic diagram of an embodiment of a communication system for transmitting radio frequency (RF) signals. [Figure 9] FIG. 1 is a schematic diagram of a multi-level supply (MLS) modulation system according to an embodiment. [Figure 10] FIG. 1 is a schematic diagram of an MLS DC / DC converter according to an embodiment. [Figure 11] FIG. 1 is a schematic diagram of an example of timing for MLS DC / DC conversion. [Figure 12] FIG. 2 is a schematic diagram of an example of MLS envelope tracking for a continuous wave signal. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] The following detailed description of certain embodiments provides various descriptions of specific embodiments. However, the innovations described herein are, for example, as defined and covered by the claims. The present invention can be embodied in many different forms, as will be described in detail below. Reference is made to the drawings in which numerals indicate identical or functionally similar elements. It is to be further understood that elements illustrated in the drawings are not necessarily to scale. The embodiments may include more elements and / or portions of the elements shown in the drawings. Further, some embodiments may include any combination of features from two or more figures. It may also include a suitable combination.

[0029] Envelope tracking is a method to measure the power added efficiency (PAE) of a power amplifier based on the amount of power it amplifies. Efficiently controls the voltage level of the power amplifier supply voltage in relation to the envelope of the line frequency (RF) signal. This is a technique that can be used to increase the power dissipation by controlling the RF As the signal envelope increases, the voltage supplied to the power amplifier may also increase. As the signal envelope decreases, the voltage supplied to the power amplifier also decreases, resulting in lower power consumption.

[0030] Envelope tracking is used in applications where the envelope signal follows the fast changing instantaneous power of the RF signal. In other applications, the envelope signal may be, for example, It may be quite slow, determined by long time averaging. For example, When using symbols based on the 12-bit 12-bit LSB, the envelope signal is multiplexed using orthogonal frequency division multiplexing (OFDM). It changes relatively infrequently compared to the fast-changing instantaneous power of OFDM signals. For example, for a 5G OFDM waveform, the instantaneous power is required to change between peaks and valleys in less than 10ns. The symbol can change every 16 μs, whereas the The tether signal can be based on the next arriving peak of the RF signal, so it is easier to follow the RF power. rather it predicts RF power.

[0031] A multi-level envelope tracking system with regulated voltage steps is provided. In one embodiment, an envelope tracking system is provided for generating a power amplifier supply voltage for a power amplifier. The envelope tracking system is a MLS DC / DC converter that outputs multiple regulated voltages. A time-dependent envelope signal corresponding to the envelope of the RF signal amplified by the power amplifier is used as the basis for the conversion. an MLS modulator for controlling the selection of the adjusted voltage; and an output of the MLS modulator and a power amplifier. and a modulator output filter coupled between the modulator supply voltage. In addition, the regulated voltage output by the MLS DC / DC converter based on the power level of the RF signal is The switching point adaptation circuit is configured to control the voltage level of the read voltage.

[0032] The voltage level of the regulated voltage is controlled based on the power level of the RF signal. For example, the switching power of an MLS DC / DC converter can be increased by The input voltage is adjusted based on the power level of the RF signal to provide a predicted adjustment to the regulated voltage. This allows for high efficiency over a wide range of signal power. do.

[0033] In a given implementation, the switching point adaptation circuitry may be configured to Based on the signal power value indicated for the frame, the For example, in a given system, the average and / or peak signal The amount of signal power is determined based on the transmission slot or This is known before the frame and is used to control the voltage level of the regulated voltage. It is possible.

[0034] The discrete voltage level scale is determined by the signal power (e.g. 2. Adapt the appropriate voltage levels (e.g., minimum and maximum voltage values) corresponding to the By this, it is possible to achieve improved performance of the multi-level envelope tracking system. The tracking is applicable to a wide range of transmission systems, including but not limited to Time Division Duplexing (TDD). This can be done for the scenario.

[0035] Thus, in a given implementation, the power amplifier supply voltage is The power consumption can be controlled based on the peak power expected for the system or adjusted dynamically during transmission. By controlling the regulated voltage in this manner, the selected voltage spread can be adjusted. Reducing the size of the steps to allow fine tracking of the voltage in the power amplifier can be done.

[0036] For example, before the start of transmission, the peak-to-average and average powers are known, and this knowledge allows This allows the calculation of the desired maximum and minimum voltages. Decoupling capacitors that hold the charge for each regulated voltage of the to / DC converter are provided. The input voltage can be precharged to a corresponding voltage.

[0037] By implementing the envelope tracking system in this manner, improved envelope tracking accuracy can be achieved by Over a wide range of signal powers, including when off or operating at high or low peak-to-average This can be achieved.

[0038] In certain implementations, the envelope tracking system may include a baseband filter, a power amplifier, and a It acts as a power supply that can switch between multiple voltages to supply power to the device. The power source is static or fixed compared to the modulation bandwidth of the amplitude of the RF signal waveform passing through the power amplifier. The regulated voltages are controlled to generate a certain number of different voltages. The power requirement (eg, average power) of the amplifier is adapted to the amplifier's power demand.

[0039] In a given implementation, the regulated voltage from the MLS DC / DC converter may be two or more power This is processed by two or more MLS modulators to generate the power amplifier supply voltages for the amplifier. For example, carrier aggregation systems, multiple-input multiple-output (MIMO) systems, and and / or other communication systems may also operate using a shared MLS DC / DC converter. In an implementation, the switching point adaptation circuitry determines the maximum signal amplified by the power amplifier. The regulated voltage is controlled based on the signal power.

[0040] For example, in MIMO or carrier aggregation where multiple power amplifier paths operate simultaneously. In the case of a power amplifier, the envelope tracking system determines the appropriate voltage shift for the power amplifier to carry most of the power. This advantageously allows the highest power consumption brand to be selected first. This allows for a reduction in power consumption by matching the voltage to the switch. By using a single modulator switch position for one power amplifier in , and allowing other voltages to be used by the modulator for the second power amplifier. Therefore, it may be advantageous to set a fixed supply for one power amplifier.

[0041] In a given implementation, a Digital Pre-Distortion (DPD) system Knowledge of amplifier supply voltage (Vcc), filter characteristics and power amplifier response calibration Based on this, voltage settings are pre-calculated to provide pre-distortion to the RF.

[0042] FIG. 1 is a schematic diagram of a mobile device 70 according to an embodiment. , Primary antenna 1, Diversity antenna 2, Primary antenna tuning circuit 3, Di 4 versatile antenna tuning circuits, double-pole double-throw (DPDT) antenna diversity Switch 5, Primary Front-End Module 6, Diversity Front-End Module 7, battery 8, multi-level supply (MLS) envelope tracker 9, transceiver 10, baseband It includes a modem 11 and an application processor 12 .

[0043] Although one embodiment of a portable device is shown, the teachings herein may be used in a wide variety of configurations. The present invention is applicable to mobile devices implemented in a variety of ways. Therefore, other implementations are possible.

[0044] In the illustrated embodiment, the primary front-end module 6 includes a first power amplifier 21, A second power amplifier 22, a third power amplifier 23, a fourth power amplifier 24, and a first low noise amplifier 31 , a second low noise amplifier 32, a third low noise amplifier 33, a diplexer 42, a transmission / reception band switch switch 41, a transmission filter 43, a first duplexer 45, a second duplexer 46, a third duplexer a multiplexer 47, a first receiving filter 51, a second receiving filter 52, and a third receiving filter 53 , a first directional coupler 59, and a second directional coupler 60. Additionally, The front-end module 7 includes a first low-noise amplifier 35, a second low-noise amplifier 36, a first receiving a first reception filter 55, a second reception filter 56, a first reception band selection switch 61, and a second reception A band selection switch 62 is included.

[0045] Although one embodiment of a front-end circuit is shown, other embodiments of the front-end circuit may be used. For example, the front-end circuit may transmit and receive from one or more antennas. and / or a power amplifier (PA), low noise amplifier (LNA) for processing the received RF signal , filters, switches, phase shifters, duplexers, and / or other suitable circuits. Examples of front-end functions are signal amplification for transmission, signal amplification for reception, signal filtering, etc. switching between different bands, switching between different power modes, Switching between transmit and receive modes, duplexing signals, multiplexing signals diplexing or triplexing, or any combination of these This includes, but is not limited to:

[0046] Therefore, the primary front-end module, the diversity receiving front-end module Other implementations of the algorithm, antenna selection, and / or antenna tuning may also be used.

[0047] As shown in FIG. 1, the MLS envelope tracker 9 is a power amplifier in a mobile device 70. The device generates one or more power amplifier supply voltages for amplifying RF signals for wireless transmission purposes. In the illustrated embodiment, the MLS envelope tracker 9 receives battery power from the battery 8. Pressure V BATT , and a first power amplifier supply voltage V for the first power amplifier 21. PA1 , and and a second power amplifier supply voltage V for the first power amplifier 22. PA2 Generate the MLS envelope. Although an example is shown in which the line tracker 9 generates two power amplifier supply voltages, ML The S envelope tracker 9 may generate a power amplifier supply voltage that is greater or less than this.

[0048] The MLS envelope tracker 9 tracks the envelope of the first RF signal amplified by the first power amplifier 21. The first power amplifier supply voltage V PA1 Additionally, the MLS envelope tracker 9 The second power amplifier 22 is configured to track the envelope of the second RF signal that it amplifies. Supply voltage V PA2 In a given implementation, the MLS envelope tracker 9 controls the base The MLS envelope tracker 9 receives one or more envelope signals from a band modem 11. For example, the MLS envelope tracker 9 may A first envelope signal showing an envelope of the first RF signal and a second envelope signal showing an envelope of the second RF signal. The envelope signal may be analog or digital.

[0049] Battery 8 includes, for example, a lithium ion battery for use in portable device 70. Any suitable battery may be used. Battery voltage V BATT is the DC / D C converter and used for multi-level envelope tracking according to the teachings herein. A regulated voltage is generated that is

[0050] The transceiver 10 generates an RF signal for transmission and transmits it to the primary antenna 1 and the diversity antenna 2. It processes the incoming RF signal received from antenna 2. It will be understood that the transmission of the RF signal The various functions associated with receiving and transmitting are collectively represented in FIG. This can be achieved by one or more components that are A separate component (e.g., a separate circuit or die) is provided to handle the RF signals of the This is also fine.

[0051] The baseband modem 11 transmits and receives signals to the transceiver 10 to generate RF signals for transmission. The baseband modem 11 also provides a digital representation of the transmit signal for processing by the transmitter 10. A receiver 10 processes a digital representation of the received signal.

[0052] As shown in FIG. 1, the baseband modem 11 is the primary application in the mobile device 70. The computer is coupled to an application processor 12 which is responsible for providing application processing. The application processor 12 handles memory management, graph processing, and / or multimedia. Suitable for supporting applications including but not limited to decoding A wide variety of functions can be provided, such as providing a variety of system capabilities.

[0053] Although the portable device 70 illustrates an example of a multi-level envelope tracker RF system. Regardless of the above, one or more multi-level envelope trackers implemented in accordance with the teachings herein may be used in a variety of applications. The NI 8111 can be included in a variety of RF systems.

[0054] 2-3B are schematic diagrams of envelope tracking systems for power amplifiers according to various embodiments. However, the teachings herein may be implemented in a wide variety of ways. Therefore, other implementations are possible.

[0055] FIG. 2 is a schematic diagram of an envelope tracking system 100 for a power amplifier 71 according to one embodiment. FIG. 1 is a diagram showing an envelope tracking system 100 including an MLS DC / DC converter 72, a switching power supply 73, and a The MLSD includes an input adaptation circuit 75, an MLS modulator 81, and a modulator output filter 91. The C / DC converter 72 is also called a switching regulator.

[0056] The power amplifier 71 receives an RF input signal RF IN is amplified to produce an RF output signal, RF OUT Generate The MLS modulator 81 receives an RF input signal RF IN The envelope signal varies relative to the envelope of Receive (ENVELOPE).

[0057] In the illustrated embodiment, the MLS DC / DC converter 72 converts the battery voltage V BATT Received , various regulated voltages V MLSa , V MLSb , V MLSc , … V M LSnAlthough four MLS voltages are shown in the example, However, the MLS DC / DC converter 72 may have more than this, as indicated by the ellipsis. The input may generate a smaller or greater MLS voltage.

[0058] The MLS modulator 81 outputs the regulated voltage V MLSa , V MLSb , V MLSc , … V MLS n and the envelope signal, and provides the modulator output voltage to a modulator output filter 91. In an exemplary implementation, the MLS modulator 81 selects an appropriate adjustment voltage over time based on the envelope signal. For example, the MLS modulator 81 controls the output voltage based on the selection of the envelope signal. Based on the value, the adjusted voltage V MLSa , V MLSb , V MLSc , … V MLSn Of It may include a bank of switches that selectively connects one of the regulated voltages to the output of the modulator.

[0059] The modulator output filter 91 filters the output of the MLS modulator 81. and the power amplifier supply voltage V for the power amplifier 71. PA Generate.

[0060] As shown in FIG. 2, the envelope tracking system 100 also includes a switching point adaptor. The switching point adaptation circuit 75 also includes a RF signal RF IN Power Level Based on the adjusted voltage V MLSa , V MLSb , V MLSc , … V MLSn One or more of In a given implementation, the switching point The signal adaption circuit 75 is a MLS DC / DC converter used for regulation (see, for example, FIG. 11). By controlling the pulse width of converter 72, the switching points of the regulation and the corresponding regulation Control the saved voltage level.

[0061] RF signal RF IN The adjusted voltage V based on the power level MLSa , V MLSb , V M LSc , … V MLSn By controlling the voltage level of the For example, the switching point of the MLS DC / DC converter 72 can be set to the It allows for predictable adjustment of the regulated voltage as it can be adapted based on power levels. This allows for increased efficiency over a wide range of signal powers.

[0062] In certain implementations, the switching point adaptation circuit 75 may be configured to The adjusted voltage V MLSa , V MLSb , V MLS c , … V MLSn For example, the switching point adaptation circuit 75 receives data indicative of an amount of transmit power from a baseband modem or other suitable source. It is possible.

[0063] The envelope tracking system 100 is a single-ended signal tracking system with symbol tracking that may be suitable for high bandwidth modulation. It is well suited for applications that use symbols. For example, When using 5V, program the two MLS voltages to match the symbol rate (for example, 5 In other words, the MLS modulator 81 can be used continuously for The voltage used to generate the power amplifier supply voltage is shifted to a new voltage holding capacitor. The voltage can be changed by switching the voltage.

[0064] FIG. 3A illustrates an envelope tracking system 101 for a power amplifier module 101 according to another embodiment. 1 is a schematic diagram of an envelope tracking system 150. The envelope tracking system 150 includes an envelope tracking integrated circuit (IC) 1 02, modulator output filter 104, envelope shaping circuit 105, envelope signal conditioning A decoupling circuit 106, a switching point adaptation circuit 109, a first decoupling capacitor 1 The circuit includes an eleventh to fourth decoupling capacitors 114 and an inductor 117.

[0065] Although an embodiment envelope tracking system is shown in FIG. , are applicable to envelope tracking systems implemented in a wide variety of ways. An implementation example is also possible.

[0066] In the illustrated embodiment, the envelope tracking IC 102 includes an MLS switching circuit 121, A digital control circuit 122, a baseband MLS modulator 123, and a modulator control circuit 124 The envelope tracking IC 102 of FIG. BATT ) reception and switching Receiving switching point adaptation data from the point adaptation circuit 109, serial peripheral Communication via the serial interface (SPI), receiving the envelope signal (ENVELOPE), The connections to the decoupling capacitors 111 to 114 and the inductor 117 are The envelope tracking IC is also depicted with various pins or pads that serve various functions. Also referred to herein as an envelope tracking semiconductor die or chip.

[0067] MLS switching circuit 121 controls the current through inductor 117 to provide voltage regulation. For example, the MLS switching circuit 121 includes a switch and a controller. The controller may be any suitable modulation scheme (including but not limited to pulse width modulation). This switch is turned on and off using a scheme to provide DC / DC conversion. In an embodiment, the MLS switching circuit 121 provides four regulated However, the MLS switching circuit 121 outputs a more The input voltage may be implemented to output a smaller or less regulated voltage.

[0068] As shown in FIG. 3A, the MLS switching circuit 121 includes a digital control circuit 122. The digital control circuit 122 controls the programmability of the MLS switches. The signal may be provided to modulation circuit 121, MLS modulator 123, and / or modulator control circuit 124. As shown in FIG. 3A, the digital control circuit 122 is coupled to the SPI bus. In one embodiment, the digital control circuit 122 is connected to a SPI bus and / or other chip interface. The MLS switching circuit 121, the MLS modulation 123 and / or the modulator control circuit 124.

[0069] The baseband MLS modulator 123 is coupled to the power amplifier supply via a modulator output filter 104. Voltage V PA In certain implementations, the baseband MLS modulator includes an output coupled to the 123 is a switch coupled between each adjusted MLS voltage and the modulator output filter 104. Additionally, the switch of the modulator is controlled by a modulator controller 1 based on the envelope signal. 24 is selectively opened and closed.

[0070] In the illustrated embodiment, the modulator output filter 104 includes a first series inductor 127, The second series inductor 128, the first shunt capacitor 125, and the second shunt capacitor Although one implementation of the modulator output filter is depicted in FIG. The teachings herein are applicable to modulator output filters implemented in a wide variety of ways. Thus, other implementations of filters may be used in accordance with the teachings herein.

[0071] In certain implementations, one or more components of the filter may be configured to provide flexibility and / or control. and / or For example, in the illustrated embodiment, the first shunt capacitor The bottom capacitor 125 and the second shunt capacitor 126 have controllable capacitance values. Although two examples of controllable filter components are shown, other filters Components may additionally or alternatively be implemented to be controllable.

[0072] In the illustrated embodiment, the power amplifier module 101 includes a power amplifier 107 and a power supply The supply voltage filter 108 includes a series inductor 133, a first shunt The power amplifier module includes a first shunt capacitor 131 and a second shunt capacitor 132. Although one implementation of the model is shown, the teachings herein may be implemented in a wide variety of ways. It is also applicable to power amplifier modules, therefore other implementations are possible.

[0073] As shown in FIG. 3A, the switching point adaptation circuit 109 is 1, a voltage estimation circuit 142, and an MLS programming circuit 143. 41 is an RF signal IN In certain implementations, the method operates to estimate the signal power of The power estimation circuit 141 estimates the signal power digital associated with a particular transmission frame or slot. Receive the data.

[0074] The voltage estimation circuit 142 estimates the voltage among the multiple regulated output voltages of the MLS switching circuit 121. and operative to estimate a desired voltage level of one or more regulated output voltages based on the estimated power. The MLS programming circuit 143 operates the MLS switching circuit based on the estimated voltage. In the illustrated embodiment, the MLS switch operates to program the The control circuit 121 is programmed via an interface separate from the SPI bus. In another embodiment, the switching point adaptation circuit 109 is and / or via other common interfaces with the envelope tracking IC 102. The switching circuit 121 is programmed.

[0075] Although one embodiment of a switching point adaptation circuit is shown, the teachings herein is also applicable to switching point adaptation circuits implemented in a wide variety of ways.

[0076] FIG. 3B is a schematic diagram of another embodiment of an envelope tracking system 160. The system 160 includes an envelope tracking IC 152, a first modulator output filter 104a, a second modulator output filter 104b, and a Output filter 104b, first envelope shaping circuit 105a, second envelope shaping circuit 105b, 1 envelope signal conditioning circuit 106a, 2 envelope signal conditioning circuit 106b, switching point adaptation circuit 109, first decoupling capacitor 111 1 through the fourth decoupling capacitor 114, and the inductor 117. The ray tracing system 160 detects the first power amplifier supply for the first power amplifier module 101a. Supply voltage V PA1 , and a second power amplifier supply voltage for the second power amplifier module 101b. Pressure V PA2 Generate.

[0077] In the illustrated embodiment, the envelope tracking IC 152 includes an MLS switching circuit 121, Digital control circuit 122, first baseband MLS modulator 123a, second baseband MLS modulator 123b, a first modulator control circuit 124a, and a second modulator control circuit 124b. .

[0078] The envelope tracking system 160 of FIG. 3B is similar to the envelope tracking system 150 of FIG. 3A. However, the envelope tracking system 160 may use multiple modulations to generate multiple power amplifier supply voltages. In one implementation, a common or shared MLS DC / DC converter is used in combination with a It differs in that it includes examples.

[0079] In a given implementation, the regulated voltage from the MLS DC / DC converter may be two or more power This is processed by two or more MLS modulators to generate the power amplifier supply voltages for the amplifier. In a particular implementation, the switching point adaptation circuit is amplified by a power amplifier. The regulated voltage is controlled based on the maximum signal power.

[0080] FIG. 4 is a graph of voltage versus time for five example signal waveforms at different power levels. The examples shown are , 20MHzW in 5 levels MCS0 with 30MHz power supply filter bandwidth Plotted against the LAN waveform.

[0081] As shown in FIG. 4, the five voltage levels in this example are the minimum and maximum voltage levels. The amplitude of the signal is set so that the maximum and minimum match the minimum and maximum of the time-varying waveform. For example, Figure 4 shows five different plots of amplitude versus time pulse tracking for five different average powers. Draw the voltage scale.

[0082] FIG. 5A is a graph of an example of power amplifier supply voltage versus input power. This example is adapted The voltage scale for 24 dBm power is shown for which no voltage table has been provided. The maximum peak power is between 0.7V and 5.5V, with 5.5V corresponding to a maximum peak power of 35dBm, which is the typical It achieves an average output power of 30.5 dBm for typical LTE waveforms.

[0083] FIG. 5B is an example graph of power added efficiency (PAE) versus output power for various example signal waveforms. It's rough.

[0084] A single voltage is selected for each power on the x-axis, so that for a given voltage at each power, The efficiency curve is obtained by selecting the single voltage combination for each power. , a jagged overlay efficiency curve representative of the achievable power amplifier efficiency for the system. Draw a line.

[0085] This example shows results for various waveforms, with approximately 35% power amplifier loss at 24 dBm. The efficiency is average.

[0086] FIG. 6A is another example graph of power amplifier supply voltage versus input power. This example is adapted 1 shows a voltage scale for a power of 24 dBm with an example of a voltage step. The input voltage ranges between 1.7V and 2.7V, and 2.7V provides a maximum peak power of 28.5dBm. and meets an average output power of 24 dBm for typical LTE waveforms.

[0087] FIG. 6B is another example graph of PAE versus output power for various example signal waveforms. The example shows results for various waveforms, with an average power amplifier efficiency of about 42% at 24 dBm. This is a significant improvement over the 35% efficiency number associated with FIG. 5B. This is achieved by choosing a low voltage precisely matched to the average transmit power of 24 dBm. The efficiency of the power amplifier is significantly improved.

[0088] FIG. 7 is a schematic diagram of a portable device 800 according to another embodiment. 0 includes a baseband system 801, a transceiver 802, a front-end system 803, Antenna 804, power management system 805, memory 806, user interface 807, and a battery 808.

[0089] The mobile device 800 may be a 2G, 3G, 4G (LTE, LTE Advanced, and LTE Advanced Pro), 5G, WLAN (e.g. Wi-Fi), WPAN (e.g. B Bluetooth (registered trademark) and ZigBee (registered trademark), WMAN (e.g. Wi Max), and / or use a wide variety of communication technologies, including but not limited to GPS technology. can be used to communicate with each other.

[0090] The transceiver 802 generates RF signals for transmission and receives incoming signals from the antenna 804. Processes RF signals. It will be understood that the functions associated with transmitting and receiving RF signals are The various functions may be implemented by one or more components collectively represented in FIG. 7 as a transceiver 802. In one example, a device that is required to handle a given type of RF signal may be used. Alternatively, separate components (eg, separate circuits or dies) may be provided.

[0091] The front-end system 803 transmits to the antenna 804 and / or In the illustrated embodiment, the front The end system 803 includes a power amplifier (PA) 811, a low noise amplifier (LNA) 812, It includes a filter 813, a switch 814, and a duplexer 815. However, other An implementation example is also possible.

[0092] For example, the front-end system 803 amplifies a transmission signal, amplifies a reception signal, and Filtering, switching between different bands, switching between different power modes, Switching between transmit and receive modes, duplexing signals, Multiplexing (e.g. diplexing or triplexing), or may provide a number of functions, including but not limited to any combination of these. can.

[0093] In certain implementations, the mobile device 800 supports carrier aggregation. This provides the flexibility to increase peak data rates. The system supports frequency division duplexing (FDD) and time division duplexing (TDD). Since it can be used for both, it can aggregate multiple carriers or channels (aggregation). Carrier aggregation is the process of linking multiple mobile stations within the same operating frequency band. This includes contiguous aggregation, where consecutive carriers are aggregated. Carrier aggregation is not contiguous. The carriers may be consecutive, or may include frequency separated carriers within a common band or within different bands.

[0094] The plurality of antennas 804 may include antennas used for a variety of different types of communications. For example, antenna 804 may receive signals associated with a wide variety of frequencies and communication standards. The radio frequency may include an antenna associated with transmitting and / or receiving the radio frequency.

[0095] In certain implementations, antenna 804 may be used for MIMO communications and / or switched diversity communications. For example, MIMO communication uses a single radio frequency channel. MIMO communication uses multiple antennas to communicate multiple data streams over a wireless High signal-to-noise ratio, improved code generation due to spatial multiplexing of the environment Benefit from reduced signal interference and / or better signal quality. refers to a communication in which a particular antenna is selected to operate at a particular time. A group of antennas may be selected based on various factors such as packet error rate and / or signal strength indicators. A switch can be used to select the antenna.

[0096] The mobile device 800 may operate with beamforming in certain implementations. For example, the front-end system 803 may include a variable phase Optionally, the phase shifter may include a phase shifter having a phase shifter 804. The antenna is controlled to provide beam forming and directionality for the transmission and / or reception of signals. For example, in the context of signal transmission, the phase of a transmit signal provided to antenna 804 may be 804 are coupled using constructive and destructive interference. Aggregated transmission exhibits a beam-like quality with strong signal strength that is controlled and propagates in a given direction. In the context of signal reception, phase refers to the time it takes for a signal to reach the antenna from a particular direction. 804 so that as much signal energy as possible is received. In one embodiment, the antenna 804 is configured to receive one or more arrays of signals to enhance beamforming. Includes an antenna element.

[0097] The baseband system 801 receives various user input / output (I / O) signals such as voice and data. The baseband system 80 is coupled to a user interface 807 that facilitates processing of the 1 provides the transceiver 802 with a digital representation of the transmitted signal, which the transceiver 802 processes. The baseband system 801 also includes a transceiver 802. As shown in FIG. 7, the mobile device also processes a digital representation of the received signal. The baseband system 801 is coupled to a memory 806 to facilitate operation of the system 800. .

[0098] The memory 806 may be used to facilitate operation of the mobile device 800 and / or to store user information. It can be used for a wide variety of purposes, such as storing data and / or instructions, to provide storage. It is possible.

[0099] The power management system 805 provides a number of power management functions for the mobile device 800. The force management system 805 may include an MLS envelope tracker implemented in accordance with one or more aspects of the present disclosure. 860.

[0100] As shown in FIG. 7, the power management system 805 receives a battery voltage from a battery 808. Battery 808 may be, for example, a lithium ion battery for use in portable device 800. The battery may be any suitable battery, including

[0101] FIG. 8 is a schematic diagram of an embodiment of a communication system 950 for transmitting RF signals. The signal receiving system 950 includes a battery 901, an MLS envelope tracker 902, a power amplifier 903, a directional A differential coupler 904, a duplexing switching circuit 905, an antenna 906, a base Band processor 907, signal delay circuit 908, digital pre-distortion (DPD) Circuit 909, I / Q modulator 910, observation receiver 911, intermodulation detection circuit 912, envelope A delay circuit 921, a coordinate rotation digital calculation (CORDIC) circuit 922, a shaping circuit 923, It includes a digital-to-analog converter 924 and a reconstruction filter 925 .

[0102] The communication system 950 of FIG. 8 may be an envelope tracking system implemented in accordance with one or more aspects of the present disclosure. 1 shows an example of an RF system that may include a system. However, the teachings herein may be applied to a wide variety of The present invention is applicable to RF systems implemented in various ways.

[0103] The baseband processor 907 generates a sine wave or sinusoidal signal of the desired amplitude, frequency and phase. It operates to generate in-phase (I) and quadrature (Q) signals corresponding to the signal components. For example, the I and Q signals provide an equivalent representation of a sine wave. In a given implementation, the I signal The baseband processor 907 outputs the baseband signal and the Q signal in digital form. The baseband processor 90 may be any suitable processor for processing signals. 7 is a digital signal processor, microprocessor, programmable core, or It may include any combination of these.

[0104] A signal delay circuit 908 provides an adjustable delay to the I and Q signals and the envelope tracker 902 and R F signal RF IN The delay provided by the signal delay circuit 908 helps control the relative consistency between the The amount is controlled based on the amount of intermodulation in adjacent bands detected by intermodulation detection circuit 912.

[0105] The DPD circuit 909 digitally decodes the delayed I and Q signals from the signal delay circuit 908. Provides filter shaping and generates digitally predistorted (DPD) I and Q signals In the illustrated embodiment, the DPD provided by the DPD circuit 909 operates as follows: The DPD circuit 909 is controlled based on the amount of intermodulation detected by the intermodulation detection circuit 912. , reducing distortion of the power amplifier 903 and / or increasing the efficiency of the power amplifier 903. It plays an important role in adding value to the society.

[0106] The I / Q modulator 910 receives the digitally predistorted I and Q signals. These signals are called RF signals. IN For example, an I / Q modulator The 910 converts the digitally predistorted I and Q signals into analog form. and a DAC configured to up-convert the analog I and Q signals to radio frequency (RF). A mixer that downconverts the I and Q signals and combines them to produce an RF signal. No. RF IN In certain implementations, the I / Q modulator 910 may include a signal combiner. one or more filters configured to filter frequency components of a signal to be processed; may include.

[0107] The envelope delay circuit 921 delays the I and Q signals from the baseband processor 907. Additionally, a CORDIC circuit 922 processes the delayed I and Q signals, RF signal RF IN A digital envelope signal is generated that represents the envelope of the CORDI signal. Although one implementation using C circuit 922 is shown, the envelope signal may be obtained in other manners. It is also possible.

[0108] The shaping circuit 923 shapes the digital envelope signal to enhance the performance of the communication system 950. In certain implementations, the shaping circuit 923 operates to: A shaping table is included that maps each level to a corresponding shaped envelope signal level. The shaping helps to control the linearity, distortion, and / or efficiency of the power amplifier 903. obtain.

[0109] In the illustrated embodiment, the shaped envelope signal is converted to a differential analog signal by the DAC 924. Optionally, the differential analog envelope signal is a digital signal converted to a differential analog envelope signal. The differential envelope of the MLS envelope tracker 902 is filtered by the reconstruction filter 925. Differential envelope signals ENV_p, ENV_n suitable for use by the envelope amplifier are generated. In certain implementations, the reconstruction filter 925 includes a differential low-pass filter.

[0110] Although an example of envelope signaling is provided, the teachings herein may be implemented in a wide variety of manners. The present invention is also applicable to envelope signaling implemented in a multi-layered signal processing system. For example, in another embodiment, MLS envelope tracking is used. Priority is given to providing digital envelope data to the DAC 924 and reconstruction filter 902. Ruta 925 is omitted.

[0111] Continuing to refer to FIG. 8, the MLS envelope tracker 902 receives the signal from the reconstruction filter 925 as Receives the envelope signal and detects the battery voltage V BATT Receive the differential envelope signal The power amplifier supply voltage V for the power amplifier 903 is determined using the numbers ENV_p and ENV_n. C C_PA Generate the power amplifier supply voltage V CC_PA is the RF signal IN In the envelope of The power amplifier 903 outputs the RF signal RF from the I / Q modulator 910. IN Received RF signal RF OUT In this example, a duplexing switching circuit The signal is applied to an antenna 906 via a line 905 .

[0112] The directional coupler 904 connects the output of the power amplifier 903 to the duplexing switching circuit. 905, a duplexing switching circuit 90 This allows measurement of the output power of the power amplifier 903, which does not include the insertion loss of the directional coupler 9 The detected output signal of the detector 9104 is provided to an observation receiver 911. The observation receiver 911 A mixer that provides down-conversion to generate up-converted I and Q signals. and generating an I observation signal and a Q observation signal from the down-converted I signal and Q signal. and a DAC that configures the DAC.

[0113] The intermodulation detection circuit 912 couples the I and Q observation signals to the baseband processor 907. Optionally, an intermodulation detection circuit 912 determines intermodulation products with the I and Q signals from the The difference is calculated by controlling the DPD provided by the DPD circuit 909 and / or the delay of the signal delay circuit 908. Dynamic envelope signals ENV_p, ENV_n and RF signal RF IN Controls the relative consistency with In another embodiment, the intermodulation detection circuit 912 may additionally or alternatively include a signal delay circuit 92 Controls the delay of 1.

[0114] By including a feedback path from the output of the power amplifier 903 and the baseband , I and Q signals to optimize operation of the communication system 950. For example, by configuring the communication system 950 in this manner, it is possible to control power, It can help compensate for transmitter impairments and / or perform DPD.

[0115] Although shown as a single stage, power amplifier 903 may include one or more stages. Additionally, the teachings herein are applicable to communication systems that include multiple power amplifiers.

[0116] FIG. 9 is a schematic diagram of an MLS modulation system 1050 according to one embodiment. The modulation system 1050 includes a modulator control circuit 1020, an MLS DC / DC converter 1025, a converter a modulator switch bank 1027 and a decoupling capacitor bank 1030 .

[0117] The MLS modulation system 1050 of FIG. 9 is suitable for incorporation into a multi-level envelope tracker. An example of an implementation of a suitable MLS modulator circuit is shown below. However, it should be understood that the implementation may be implemented in accordance with the teachings herein. The multi-level envelope tracker may include other implementations of the MLS modulator circuit.

[0118] The MLS DC / DC converter 1025 converts the battery voltage V BATT By providing DC / DC conversion and based on the first regulated voltage V MLS1 , the second regulated voltage V MLS2 , and the third adjustment Voltage V MLS3 Although an example with three regulated voltages is shown, Instead, the MLS DC / DC converter 1025 may produce a regulated voltage that is greater or less than this. In certain implementations, at least a portion of the regulated voltage may be equal to the battery voltage V B ATT Additionally or alternatively, one or more of the regulated voltages may be boosted relative to the battery voltage. Pressure V BATT is the back voltage having a lower voltage than

[0119] The decoupling capacitor bank 1030 is generated by the MLS DC / DC converter 1025. For example, the decoupling capacitor bank in FIG. 1030 is the first adjustment voltage V MLS1 The first decoupling capacitor TA1031, second adjustment voltage V MLS2 A second decoupling capacitor that decouples the 1032, and the third adjustment voltage V MLS3 The third decoupling capacitor Includes Pacita 1033.

[0120] Continuing to refer to FIG. 9, the modulator switch bank 1027 switches the output of the modulator (MOD OUT ) and the first adjustment voltage VMLS1 a first switch 1041 connected between the Output of the device and the second adjustment voltage V MLS2 A second switch 1042 connected between the The modulator output and the third adjustment voltage V MLS3 and a third switch 1043 connected between the The modulator control unit 1020 selectively opens and closes the switches 1041 to 1043 to control the output of the modulator. Acts to control force.

[0121] FIG. 10 is a schematic diagram of an MLS DC / DC converter 1073 according to one embodiment. The LSDC / DC converter 1073 includes an inductor 1075, a first switch S1, a second switch switch S2, a third switch S3, a fourth switch S4, a fifth switch S5, and a sixth switch S 6. The MLS DC / DC converter 1073 further includes a switch that provides regulation of the opening and closing of the switch. 10. It also includes a control circuit (not shown in FIG. 10) for

[0122] The MLS DC / DC converter 1073 of FIG. 10 is incorporated into a multi-level envelope tracker. An example of an implementation of a MLS DC / DC converter suitable for use in this application is shown below. However, following the teachings herein, The multilevel envelope tracker implemented in this way includes other implementations of MLS DC / DC converters. That's fine.

[0123] In the illustrated embodiment, the first switch S1 is connected to the battery voltage V BATT Electrically connected to a first end of the second switch S2 and a first end of the inductor 1075 electrically connected to the first end of the second switch S2 and a second end connected to the first supply or the ground supply V G ND FIG. 10 shows a power supply using a ground supply and a battery voltage. Although the teachings herein show the configuration of a DC / DC converter powered by The invention is also applicable to DC / DC converters powered using any suitable power supply. The inductor 1075 further includes a first terminal of each of the third switch S3 to the sixth switch S6. The third switch S3 further includes a second end electrically connected to the ground supply V GND To The fourth switch S4, the fifth switch S5 and the sixth switch S6 also include a second terminal electrically connected thereto. Each of the S6 outputs the first regulated voltage V MLS1 , the second regulated voltage V MLS2 and 3 Regulated voltage V MLS3 and a second end configured to generate each of the

[0124] The first switch S1 to the sixth switch S6 adjust the regulated voltage to a specific error of the target voltage level. An example having three regulated voltages is shown. However, the MLS DC / DC converter 1073 may have more or less It may be implemented to generate a regulated voltage.

[0125] In the illustrated embodiment, the MLS DC / DC converter 1073 converts the battery voltage V BATT Yo and / or to generate a regulated boost voltage greater than the battery voltage V BATT than Operates as a buck-boost converter that can be used to generate a small regulated buck voltage However, other implementations are possible.

[0126] FIG. 11 is a schematic diagram of an example of timing for MLS DC / DC conversion. As shown in Fig. 1, the width of the regulation cycle is set to the regulation frequency generated by the MLS DC / DC conversion. For example, one MLS regulator can be used to control the voltage level of the applied voltage. the adjusted voltage is associated with a period t1, while the second adjusted voltage is associated with a different period t2. Additionally, non-overlapping can be used to avoid crowbar currents between different voltage levels. The period tovlp can also be used.

[0127] In certain implementations herein, one or more adjustment periods (e.g., t1 and / or t2) and and / or one or more of the non-overlapping periods (e.g., tovlop) can be digitally controlled. In one embodiment, the delay is controlled based on a digital state machine and / or other suitable circuitry. do.

[0128] The regulated voltage produced by the MLS DC / DC conversion is selectively varied by the modulator. In the illustrated example, the modulator output filter is The circuit is depicted as including shunt capacitors C1 and C2 and series inductors L1 and L2. However, other implementations of the modulator output filter are possible.

[0129] FIG. 12 is a schematic diagram of an example of MLS envelope tracking for a continuous wave signal. An example is given for a continuous wave signal having a frequency of about 100 MHz and a corresponding period of about 10 ns. Examples of suitable MLS voltage levels for the signals are shown.

[0130] Conclusion

[0131] Some of the above embodiments have given examples relating to mobile devices. The principles and advantages of these embodiments may be applied to any other system or It can be used for the device.

[0132] Unless the context clearly requires otherwise, In this regard, the words "including," "comprises," and the like are used in an inclusive sense as opposed to an exclusive or exhaustive sense. In general, the term "including but not limited to" should be interpreted as meaning "including but not limited to" The term "coupled" as used herein means that two or more elements are directly connected or connected via one or more interconnects. It is noted here that the two components may be connected via an inter-connection element. The term "connected," as used generally, also means that two or more elements are directly connected or that one or more elements are connected by a It is noted that the present application may either be connected via an intermediate element or When used herein, the terms "herein," "upper," "lower," and words of similar import shall mean the same things as used herein. This application is hereby incorporated by reference in its entirety and not to any particular portions thereof. Where permitted, terms in the above Detailed Description using singular or plural numbers shall The terms "or" and "if" refer to a list of two or more items. The term "or" means any of the items in a list, Covers all of the items in the list, and any combination of the items in the list. .

[0133] Furthermore, unless specifically stated or understood otherwise within the context of use, Insofar as possible, the following terms are used in particular: "can," "might," "may," "may," "for example," "may Conditional language used herein, such as "such as," "such as," "such that ... It is intended that certain embodiments include certain features, elements, and / or conditions while other embodiments do not. That is, such conditional language generally indicates that the features, elements and / or states are consistent with one or more implementations. The presence of any aspect necessary for the form or the existence of one or more embodiments of the invention without the input of the authors or includes these features, elements and / or conditions, with or without prompts. The logic that determines whether or not a It is not intended to imply necessarily inclusive.

[0134] The above description of embodiments of the present invention is not intended to be exhaustive or to be construed as limiting the scope of the present invention. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Although the embodiments and examples have been described above for illustrative purposes, those skilled in the art will recognize that the present invention Various equivalent modifications are possible within the scope. For example, the processes or blocks may be arranged in a given order. While presented in the drawings, alternative embodiments may perform routines having steps in different orders. can use a system having blocks, some processes or blocks being These processes or blocks may be deleted, moved, added, subdivided, combined and / or modified. Each of the blocks may be implemented in a variety of different ways. While these processes or blocks may be shown as being executed in a sequence, Alternatively, they may be performed in parallel, or at different times.

[0135] The teachings of the present invention provided herein may be used in conjunction with other systems, not necessarily the systems mentioned above. The elements and operations of the various embodiments described above may be implemented in further embodiments. They may be combined to give form.

[0136] While certain embodiments of the present invention have been described, it will be understood that these embodiments are presented by way of example only. and are not intended to limit the scope of the present disclosure. Indeed, The novel methods and systems may be embodied in a variety of other forms and may be implemented in any manner that is consistent with the teachings set forth herein. Various omissions, substitutions and changes in the form of the methods and systems described herein may be made without departing from the spirit and scope of the present disclosure. The appended claims and their equivalents are intended to be construed as falling within the scope and spirit of the present disclosure. It is intended to cover such forms or modifications as may come within the scope of the present invention.

Claims

1. 1. An envelope tracking system comprising: A power amplifier configured to amplify a radio frequency signal and to receive power from a power amplifier supply voltage. a power amplifier formed by generating a power amplifier supply voltage based on an envelope signal corresponding to an envelope of the radio frequency signal; an envelope tracker configured to Including, The envelope tracker comprises: a DC / DC converter configured to output a plurality of regulated voltages; controlling the power amplifier supply voltage based on the plurality of regulated voltages and the envelope signal. a modulator configured to At least one of the plurality of regulated voltages is determined based on a power level of the radio frequency signal. A switching point adaptation circuit configured to control the voltage levels of the two regulated voltages. and An envelope tracking system comprising:

2. The switching point adaptation circuitry adjusts the switching point based on a power level of the radio frequency signal. The package of claim 1 configured to control a voltage level of each of the plurality of regulated voltages. Tangle tracing system.

3. The switching point adaptation circuit is configured to: and configured to estimate a power level of the radio frequency signal based on a signal power value for the 2. The envelope tracking system of claim 1, further comprising a power estimation circuit for estimating a power of the input signal.

4. The envelope tracking system of claim 3 , wherein the signal power value represents an average power.

5. The envelope tracking system of claim 3 , wherein the signal power value indicates a peak power.

6. The switching point adaptation circuit further comprises a plurality of locations associated with the signal power value.

4. The envelope tracking system of claim 3, further comprising a voltage estimation circuit configured to estimate a desired voltage level. Tem.

7. The switching point adaptation circuit further comprises: to output the plurality of regulated voltages, each having a desired voltage level. The method of claim 6, further comprising: programming circuitry configured to control the DC / DC converter. Line tracing system.

8. further comprising two or more power amplifiers configured to amplify the two or more radio frequency signals; The envelope tracker receives the plurality of regulated voltages and outputs corresponding ones of the two or more power amplifiers. Each is configured to provide a modulation that produces a supply voltage for a corresponding one of the power amplifiers.

2. The envelope tracking system of claim 1 , comprising two or more modulators.

9. The switching point adaptation circuitry is adapted to adapt to a maximum power level of the two or more radio frequency signals.

9. The envelope tracking system of claim 8, configured to control the voltage level based on

10. 2. The envelope tracking method of claim 1, wherein the plurality of regulated voltages each have a different voltage level. system.

11. The modulator couples an output of the modulator to a corresponding one of the plurality of regulated voltages.

2. The envelope tracking system of claim 1, further comprising a plurality of switches each coupled between a first input voltage and a second input voltage. Tem.

12. a modulator output filter connected between the output of the modulator and the power amplifier supply voltage; Including, The modulator output filter includes at least one series inductor and at least one shunt inductor.

2. The envelope tracking system of claim 1, further comprising a counter capacitor.

13. 1. A mobile device comprising: a transceiver configured to generate a radio frequency transmit signal; a power amplifier for amplifying said radio frequency transmit signal and receiving power from a power amplifier supply voltage; a front-end circuit including a power amplifier configured to A power amplifier supply voltage is determined based on an envelope signal corresponding to an envelope of the radio frequency transmit signal. a power management circuit including an envelope tracker configured to generate Including, The envelope tracker comprises: a DC / DC converter configured to output a plurality of regulated voltages; controlling the power amplifier supply voltage based on the plurality of regulated voltages and the envelope signal. a modulator configured to At least one of the plurality of regulated voltages based on a power level of the radio frequency transmission signal. a switching point adaptation configured to control a voltage level of the second regulated voltage. Circuit and , including mobile devices.

14. The switching point adaptation circuit is configured to: and configured to estimate a power level of the radio frequency signal based on a signal power value for the The portable device of claim 13, further comprising a power estimation circuit for estimating a power of the portable device.

15. The switching point adaptation circuit further comprises a plurality of locations associated with the signal power value.

15. The portable device of claim 14, comprising a voltage estimation circuit configured to estimate a desired voltage level. 。

16. The switching point adaptation circuit further comprises: to output the plurality of regulated voltages, each having a desired voltage level.

16. The mobile device of claim 15, further comprising a programming circuit configured to control the DC / DC converter. Mobile device.

17. two or more power amplifiers configured to amplify two or more radio frequency transmit signals; The envelope tracker receives the plurality of regulated voltages and outputs corresponding ones of the two or more power amplifiers. Each is configured to provide a modulation that produces a supply voltage for a corresponding one of the power amplifiers.

14. The mobile device of claim 13, comprising two or more modulators.

18. The switching point adaptation circuitry determines a maximum power level of the two or more radio frequency transmission signals.

20. The portable device of claim 17, configured to control the voltage level based on a

19. 1. A method of envelope tracking comprising: amplifying a radio frequency signal using a power amplifier; powering the power amplifier using a power amplifier supply voltage; outputting a plurality of regulated voltages from the DC / DC converter; A modulator is used to modulate the power amplifier supply based on the plurality of regulated voltage and envelope signals. controlling a supply voltage, said envelope signal corresponding to an envelope of said radio frequency signal; And, At least one of the plurality of regulated voltages is determined based on a power level of the radio frequency signal. Controlling the voltage levels of the two regulated voltages; A method comprising:

20. The radio based on a signal power value for at least one of a transmission frame or a transmission symbol. Estimating a power level of a frequency signal; estimating a plurality of desired voltage levels associated with the signal power values; 20. The method of claim 19, further comprising:

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