Power supply device and method for fast and smooth switching of envelope tracking and average power tracking

Abstract

The invention discloses a power supply device and method for rapidly and smoothly switching envelope tracking and average power tracking, and the device is additionally provided with a pre-charging circuit module controlled by MIPI on the basis of an original envelope tracking (ET) power supply module and an average power tracking (APT) power supply module. According to the method, seamless and efficient switching between an envelope tracking (ET) mode and an average power tracking (APT) mode is achieved through accurate MIPI control, efficient pre-charging management and a flexible power supply adjustment mechanism, and the performance and energy efficiency of wireless communication equipment are greatly optimized.

Description

Technical Field

[0001] The present invention belongs to the technical field of wireless communication equipment, and in particular relates to a power supply device and method for fast and smooth switching of envelope tracking and average power tracking. Background Art

[0002] The energy efficiency and linearity of the RF power amplifier are critical to the energy consumption and signal quality of the entire system. In the application of the UAV system, the terminal adopts an automatic power adjustment technology to judge the distance between the UAV and the receiver (console) by sampling the received downlink signal strength, and dynamically adjusts the output power of the UAV terminal PA to achieve energy saving. However, traditional power amplifiers often face the problem of reduced efficiency when performing power fallback operations, especially when the envelope tracking technology fails to quickly and effectively adapt to power changes. The alternative at this time is to implement the tracking power supply as an APT (average power tracking) power modulator to maintain the high efficiency of the power module.

[0003] Some envelope tracking modules have used these efficiency features to provide a transition between using an ET system at higher average power and using an APT system at lower average power to maintain optimal efficiency across all power levels. However, current transition techniques between ET and APT techniques can cause undesirable transient distortion that affects signal quality, resulting in poor EVM of the received signal, which can cause a drop in transmission rate or even transmission interruption. Summary of the invention

[0004] In order to overcome the technical problem in the prior art that the transmission rate decreases due to unexpected signal distortion caused by switching between the envelope tracking (ET) power mode and the average power tracking (APT) power mode, the present invention proposes an innovative circuit design. On the basis of the original envelope tracking (ET) power module and the average power tracking (APT) power module, a MIPI-controlled pre-charging circuit module is added, which can achieve a fast and smooth transition between the two working modes while ensuring signal quality.

[0005] The technical solution adopted by the present invention to solve its technical problem is: A power supply device for fast and smooth switching between envelope tracking and average power tracking, the device comprising: an envelope tracking power supply module, an average power tracking power supply module, and a pre-charging circuit module; The pre-charging circuit module can enable the envelope tracking power supply module and the average power tracking power supply module to achieve fast and smooth switching.

[0006] Preferably, the device comprises two working modes: envelope tracking mode and average power tracking mode.

[0007] Preferably, the average power tracking power supply module comprises a DC / DC voltage converter unit for providing a low-frequency component of the envelope to the envelope tracking power supply module.

[0008] Preferably, the average power tracking power supply module further includes a DAC digital-to-analog conversion unit, which together with a DC / DC voltage converter unit realizes an average power tracking function.

[0009] Preferably, the device further comprises a linear amplifier module, and the linear amplifier module is used to amplify the envelope signal.

[0010] Preferably, the linear amplifier module comprises at least one capacitor, which is connected to the output end of the linear amplifier and is used to stabilize the output voltage of the linear amplifier.

[0011] Preferably, the device also includes a radio frequency front-end control module, which receives instructions from the processor through the MIPI bus, and sends precise control signals to activate or shut down the circuit's linear amplifier module, DC / DC voltage converter unit, DAC digital-to-analog conversion unit, and pre-charging circuit module according to the received system requirements.

[0012] The present invention also provides a method for quickly and smoothly switching envelope tracking and average power tracking, comprising: Entering the average power tracking (APT) power mode: After the baseband processor module detects the change in the signal threshold, the RFFE module is enabled to first send an enable signal through MIPI to trigger the pre-charging circuit, quickly discharge the linear amplifier output capacitor, and then turn off the linear amplifier. At the same time, the DC / DC voltage converter is turned on to adjust the voltage to ensure a smooth transition from the envelope tracking (ET) power module to the average power tracking (APT) power module.

[0013] Preferably, the method further comprises: Return to envelope tracking (ET) power mode: When the signal condition changes and indicates the need to return to envelope tracking (ET) power mode, the RFFE module activates the pre-charge circuit through MIPI to charge the capacitor to the voltage required for envelope tracking (ET) power mode, and then turns on the linear amplifier. At the same time, it gradually adjusts the output of the average power tracking (APT) power module to match the envelope tracking (ET) power mode, completing a fast and smooth switch from the average power tracking (APT) power module to the envelope tracking (ET) power module.

[0014] The technical advantages of the present invention are as follows: 1) The present invention realizes seamless and efficient switching between envelope tracking (ET) and average power tracking (APT) power modes through precise MIPI control, efficient pre-charge management and flexible power adjustment mechanism, greatly optimizing the performance and energy efficiency of wireless communication equipment.

[0015] 2) In addition to improving signal quality, the pre-charging circuit of the present invention also improves overall energy efficiency by optimizing energy management. The intelligent control of the pre-charging circuit reduces unnecessary energy consumption, especially at the moment of mode conversion, ensuring the effective use of system resources, which is crucial to extending battery life and reducing operating costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a circuit diagram of an envelope tracking power supply device in one embodiment of the present invention; Figure 2 A flow chart of mode switching of an envelope tracking power supply device in one embodiment of the present invention; Figure 3 A circuit diagram of a pre-charging circuit module controlling the charging and discharging of a capacitor Cb in one embodiment of the present invention; Figure 4 It is a schematic diagram of the integration of a Precharge module and a DAC module in one embodiment of the present invention; Figure 5 The power detection circuit diagram of the radio frequency front end in one embodiment of the present invention. DETAILED DESCRIPTION

[0017] The following will refer to the attached Figures 1 to 5 Specific embodiments of the present invention are described in detail. Although specific embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0018] It should be noted that certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that technicians may use different nouns to refer to the same component. This specification and claims do not use the difference in nouns as a way to distinguish components, but use the difference in the functions of the components as the criterion for distinction. As mentioned throughout the specification and claims, "including" or "comprising" is an open term, so it should be interpreted as "including but not limited to". The subsequent description of the specification is a preferred embodiment of the present invention, but the description is based on the general principles of the specification and is not intended to limit the scope of the present invention. The scope of protection of the present invention shall be determined by the attached claims.

[0019] To facilitate understanding of the embodiments of the present invention, further explanation will be given below by taking specific embodiments as examples in conjunction with the accompanying drawings, and each of the accompanying drawings does not constitute a limitation on the embodiments of the present invention.

[0020] The present invention provides a power supply device that can quickly and smoothly switch between envelope tracking (ET) and average power tracking (APT). The power supply device is used to power a PA (power amplifier). When the system is working, the PA requires a large voltage, which can be provided by the ET power supply. When the system is on standby, the PA requires a small voltage, and it saves power by working in the average power tracking (APT) power supply mode.

[0021] like Figure 1 As shown, the power supply device includes: a radio frequency front-end control module (RFFE control module), an average power tracking (APT) power supply module, an envelope tracking (ET) power supply module and a pre-charge circuit module (Precharge module), wherein the average power tracking (APT) power supply module includes a DC / DC voltage conversion unit and a DAC digital-to-analog conversion unit, and the envelope tracking (ET) power supply module includes a DC / DC voltage conversion unit, a DAC digital-to-analog conversion unit and a linear amplifier module. The output end of the RF front-end control module is respectively connected to the average power tracking (APT) power module, the linear amplifier module and the pre-charging circuit module. The input end of the RF front-end control module is the MIPI control signal, which is sent by the MIPI interface. The first input end of the linear amplifier module inputs the envelope signal processed by the baseband processor, and the second input end is grounded. The output end of the linear amplifier module is connected to the power supply end of the power amplifier through the capacitor Cb. The output end of the average power tracking (APT) power module is connected to the power supply end of the power amplifier through the inductors L1 and L2 in turn. The output end of the inductor L1 is also connected to the GND end through the capacitor Cp. The output end of the inductor L2 is connected to the ground through the capacitor Co. The input end of the DC / DC voltage conversion unit is connected to the DC battery voltage, and the output end is connected to the DAC digital-to-analog conversion unit. The power supply end of the linear amplifier module is connected to the DC battery voltage. The capacitor Cb is used to charge and discharge to keep the voltage stable.

[0022] 1. RFFE control module (RF front-end control module) Core functions: As the "command center" of the entire circuit, the RFFE (Radio Frequency Front-End) control module receives instructions from the processor through the MIPI (Mobile Industry Processor Interface) bus, and sends precise control signals to activate or shut down the circuit's linear amplifier module, DC / DC voltage converter unit, DAC (digital-to-analog conversion) unit, and precharge (precharge circuit) module based on the received system requirements.

[0023] Technical details: The high-speed, low-power MIPI protocol is used to ensure fast transmission and low-latency response of control signals, so as to make precise control at the moment of envelope tracking (ET) and average power tracking (APT) power mode conversion, and achieve fast and smooth switching by enabling the pre-charge circuit in advance before the linear amplifier module is turned off and on.

[0024] 2. Linear amplifier module Core function: Responsible for amplifying the envelope signal from the baseband processor and providing the necessary high-speed drive voltage for the subsequent power amplifier (PA). It is an important component of the envelope tracking (ET) power supply mode.

[0025] Technical details: A large-capacity capacitor must be configured at the output end of the linear amplifier to stabilize its own output voltage. However, the capacitor needs to be released when the envelope tracking (ET) power mode is switched to the average power tracking (APT) power mode. When the average power tracking (APT) power mode is switched to the envelope tracking (ET) power mode, the capacitor needs to be charged in advance to avoid transient interference caused by the mode conversion.

[0026] 3. Average Power Tracking (APT) Power Module Core functions: It consists of a DC voltage conversion module (DC / DC) and a DAC (Digital-to-Analog Converter) module. The DC / DC voltage converter inside is used to provide the low-frequency component of the envelope to the envelope tracking (ET) power module. It can also be used alone to realize the average power tracking (APT) function together with the DAC module. It is used to dynamically adjust the supply voltage of the PA in the average power tracking (APT) power mode to achieve on-demand power supply and optimize energy efficiency.

[0027] Technical details: When the average power tracking (APT) power mode is activated, the average power tracking (APT) power module adjusts the DAC output through the internal control algorithm according to the instructions of the RFFE control module, and then controls the DC / DC voltage converter output voltage to adapt to different power requirements.

[0028] 4. Precharge module (precharge circuit module) Core function: As a key link in mode switching, the pre-charge circuit module ensures that the output capacitor of the linear amplifier module can quickly reach the target voltage level when switching between envelope tracking (ET) and average power tracking (APT) power modes through fast charging / discharging operations, thereby reducing signal distortion during the transition period.

[0029] Technical details: Use efficient switching components (such as MOSFETs) and appropriate control logic to achieve precise control of capacitor voltage. In the discharge phase, the residual voltage on the capacitor is quickly discharged by turning on the appropriate path; in the charging phase, sufficient current is provided to quickly charge the capacitor to a preset level.

[0030] The present invention also provides a method for fast and smooth switching between envelope tracking and average power tracking, such as Figure 2 As shown, the steps include: Entering the average power tracking (APT) power mode: When the baseband processor module detects the change in the signal threshold, the RFFE control module is enabled to first send an enable signal through MIPI to trigger the pre-charging circuit, quickly discharge the linear amplifier output capacitor, and then turn off the linear amplifier. At the same time, the DC / DC voltage converter is turned on to adjust the voltage to ensure a smooth transition to the average power tracking (APT) power module.

[0031] Return to envelope tracking (ET) power mode: Similarly, when the signal condition changes and indicates the need to return to envelope tracking (ET) power mode, the RFFE module activates the pre-charge circuit through MIPI to charge the capacitor to the voltage required for envelope tracking (ET) power mode, and then turns on the linear amplifier. At the same time, it gradually adjusts the output of the average power tracking (APT) power module to match the envelope tracking (ET) power mode, completing a fast and smooth switch.

[0032] Specifically, when the power supply operates in the envelope tracking (ET) power supply mode, the baseband processor module monitors the signal in real time (power detection is at the envelope input port, when the difference between the average voltage generated by the value of the envelope changing with time after passing through an integrator or the RMS voltage generated after passing through the RMS detector and the output voltage of the average power tracking (APT) power supply module is lower than a certain threshold (2dB)) threshold change. When the signal change is detected to exceed the threshold, the MIPI interface sends an enable signal to trigger the pre-charging circuit module to discharge, and at the same time sends a MIPI control signal to shut down the linear amplifier through the RF front-end control module signal. At this time, the DC / DC voltage converter unit in the average power tracking (APT) power supply module is adjusted to the average power tracking (APT) power supply mode requirements, and the transmit power of the PA is adjusted to the target value.

[0033] The power supply works in the average power tracking (APT) power mode, and the baseband processor module monitors the signal in real time (power detection is at the envelope input port. When the value of the envelope changing with time passes through an integrator to generate an average voltage or the RMS voltage generated after passing through an RMS detector and the output voltage of the average power tracking (APT) power module is greater than 2dB) threshold changes. When the signal change exceeds the threshold, the MIPI interface sends an enable signal to trigger the pre-charge circuit module to charge to the envelope tracking (ET) power mode voltage, and at the same time sends a MIPI control signal to turn on the linear amplifier through the RF front-end control module signal. The linear amplifier adjusts the average power tracking (APT) power mode output voltage, the voltage matches the envelope tracking (ET) power mode, and adjusts the transmit power on the PA to the target value. The power supply works in the envelope tracking (ET) power mode, and the baseband processor module monitors the signal in real time again.

[0034] In one embodiment, in combination Figure 3 Further explain how the pre-charge circuit module controls the charging and discharging of capacitor Cb: Figure 3 As shown, S1 and S2 are controlled switches (such as MOSFETs), which are turned on alternately, and they connect Cfly to the power supply (Vin) and transfer charge to the target capacitor (Cb). Phase 1 (charging phase): S1 is closed, S2 is open, and the flying capacitor (Cfly) is charged to the input voltage (Vin); Phase 2 (transmission phase): S1 is open, S2 is closed, and the charge stored in Cfly is transferred to Cb via D1. Cfly is a flying capacitor used to transfer charge, and Cb is a target capacitor that needs to be pre-charged to the required voltage in the envelope tracking (ET) power mode. The diode is used to guide the current in different stages of the charge pump operation. In the first stage, D2 allows the charge to flow from the power supply to the flying capacitor (Cfly), and D1 allows the charge to be transferred from Cfly to the target capacitor (Cb) in the second stage. When D1 is turned off, it has a blocking function to prevent the linear amplifier module from charging the pre-charger through point b. The function of the control circuit is to alternately change the state of S1 and S2 to achieve the required voltage on the target capacitor (Cb).

[0035] In another embodiment, in combination Figure 4 Further explanation of how the Precharge and DAC modules are integrated: Figure 4 As shown, Precharge is controlled by two switches S1 and S2. While setting the output voltage of the average power tracking (APT) power module, the feedback voltage Vfb can be directly input to the control circuit of S1 and S2 after setting the DAC to achieve precise control of the voltage on Cb.

[0036] In another embodiment, in combination Figure 5 Further explanation of the power detection of the RF front end: Figure 5 As shown, the power detection is at the envelope input port. When the difference between the average voltage generated by the time-varying envelope value after passing through an integrator or the RMS voltage generated after passing through the RMS detector and the output voltage of the average power tracking (APT) power module exceeds 2dB, the envelope tracking (ET) power mode is started. The start can be directly controlled by switch S3 or RFFE. If it is lower than 2dB, the average power tracking (APT) power mode is used.

[0037] In another embodiment, the present invention provides a solution for the UAV system by dynamically adjusting the terminal power, which can reasonably allocate power according to the actual distance and signal strength. This technology can intelligently adjust the power output according to environmental changes and communication needs, and has a certain degree of adaptability. Whether at different distances, complex environments or channel conditions, the system can respond in time to maintain the stability of the communication connection to maximize energy savings and extend the working time of the UAV, thereby improving the efficiency of task execution. This solution can maintain system quality and stability. Ensure that the UAV always operates at the optimal power level, and the communication quality between the UAV and the console and receiver is more reliable, effectively preventing signal attenuation or interference problems caused by distance.

[0038] Beneficial technical effects achieved by the present invention: 1. The present invention realizes precise control through the MIPI interface. The enable signal sent by MIPI enables the circuit to respond quickly between different working modes, ensuring the instant transmission of the control signal. Before the linear amplifier module is turned off and on, the pre-charging circuit is enabled in advance, so that the pre-charging circuit can intervene in time to prepare for the mode conversion.

[0039] 2. The design of the pre-charging circuit of the present invention is intended to reduce signal distortion during mode switching. The pre-charging circuit module achieves this by quickly and accurately managing the charging and discharging process of the output capacitor. In the discharge phase, the residual voltage on the capacitor is quickly discharged by turning on an appropriate path; in the charging phase, sufficient current is provided to quickly charge the capacitor to a preset level. This control strategy avoids unnecessary signal output caused by the residual voltage of the capacitor, thereby protecting the purity and stability of the signal.

[0040] 3. The power detection of the present invention is at the envelope input port. When the difference between the average voltage generated by the time-varying value of the envelope after passing through an integrator and the output voltage of the average power tracking (APT) power module exceeds a certain threshold, the envelope tracking (ET) power mode is started. If it is lower than the threshold, the average power tracking (APT) power mode is used, switching at the input stage instead of the output stage, so there is no output power loss, which greatly optimizes the performance and energy efficiency of the wireless communication equipment.

[0041] 4. The present invention utilizes the charging and discharging of capacitors to realize the switching of envelope tracking (ET) and average power tracking (APT) power modules. The pre-charging circuit module is enabled in advance during the mode switching process, and the output capacitor can quickly reach the target voltage level. Compared with the existing switching using switches, the delay is caused by the influence of the switching frequency. The present invention can reduce the transient distortion problem caused in the transition process. In application scenarios where frequent adjustment of the transmit power is required, this smooth switching mechanism can increase the robustness and reliability of the PA communication link powered by the envelope tracking (ET) / average power tracking (APT) power module.

[0042] 5. The power supply structure of the present invention integrates the envelope tracking (ET) and average power tracking (APT) power supply modules, and shares the DAC and DC / DC modules, eliminating the need for repeated design and configuration, greatly reducing the IC size and simplifying the power supply structure.

[0043] The above general description of the invention involved in this application and the description of its specific implementation methods should not be understood as limiting the technical solutions of the invention. Based on the disclosure of this application, those skilled in the art can, without violating the constituent elements of the invention involved, add, reduce or combine the disclosed technical features in the above general description or / and specific implementation methods (including examples) to form other technical solutions within the scope of protection of this application.

Claims

1. A power supply device for fast and smooth switching between envelope tracking and average power tracking, characterized in that: The device includes: an envelope tracking (ET) power module, an average power tracking (APT) power module, and a pre-charging circuit module; The pre-charging circuit module enables the envelope tracking power supply module and the average power tracking power supply module to achieve fast and smooth switching between the envelope tracking mode and the average power tracking mode.

2. The device according to claim 1, characterized in that Preferably, the average power tracking power supply module includes a DC / DC voltage converter unit for providing a low-frequency component of the envelope to the envelope tracking power supply module.

3. The device according to claim 2, characterized in that The average power tracking power supply module also includes a DAC digital-to-analog conversion unit, which together with a DC / DC voltage converter unit realizes an average power tracking function.

4. The device according to claim 1, characterized in that The device further comprises a linear amplifier module, wherein the linear amplifier module is used to amplify the envelope signal.

5. The device according to claim 4, characterized in that The linear amplifier module includes at least one capacitor connected to the output end of the linear amplifier.

6. The device according to claim 5, characterized in that The capacitor is used to stabilize the output voltage of the linear amplifier.

7. The device according to claim 1, characterized in that The device also includes a radio frequency front-end control module, which receives instructions from the processor through the MIPI bus and sends precise control signals to activate or shut down the linear amplifier module, DC / DC voltage converter unit, DAC digital-to-analog conversion unit, and pre-charging circuit module of the circuit according to the received system requirements.

8. A method for fast and smooth switching between envelope tracking and average power tracking, characterized in that: The method comprises: Entering the average power tracking (APT) power mode: After the baseband processor module detects the change in the signal threshold, the RFFE module is enabled to first send an enable signal through MIPI to trigger the pre-charging circuit, quickly discharge the linear amplifier output capacitor, and then turn off the linear amplifier. At the same time, the DC / DC voltage converter is turned on to adjust the voltage to ensure a smooth transition from the envelope tracking (ET) power module to the average power tracking (APT) power module.

9. The method according to claim 8, characterized in that The method further comprises: Return to envelope tracking (ET) power mode: When the signal condition changes and indicates the need to return to envelope tracking (ET) power mode, the RFFE module activates the pre-charge circuit through MIPI to charge the capacitor to the voltage required for envelope tracking (ET) power mode, and then turns on the linear amplifier. At the same time, it gradually adjusts the output of the average power tracking (APT) power module to match the envelope tracking (ET) power mode, completing a fast and smooth switch from the average power tracking (APT) power module to the envelope tracking (ET) power module.

Images