Method and circuit for improving overshoot suppression efficiency of power amplifier triggered by excitation signal

Abstract

The invention discloses a method and a circuit for improving the overshoot suppression efficiency of a power amplifier triggered by an excitation signal, and the method comprises the steps: enabling a pulse power amplifier to work in a high-efficiency class B at the front part of a microwave excitation signal, and detecting a falling edge of the excitation signal of the power amplifier through a falling edge detection circuit; before the falling edge of the excitation signal arrives, the grid bias voltage is adjusted through the voltage control circuit, the working type of the power amplifier is changed, the grid bias voltage is adjusted to the A type, and meanwhile, the position of a quiescent working point is adjusted, so that the power amplifier works in the A type mode with upper and lower waveforms symmetrically cut off; therefore, the drain voltage does not generate overshoot at the moment when the microwave excitation signal is closed, the efficiency is improved, and the problems of efficiency reduction and voltage overshoot caused by output waveform distortion due to different gains of the A-type power amplifier and the B-type power amplifier are solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of solid-state microwave power amplifiers, and particularly relates to a method and a circuit for improving the overshoot suppression efficiency of a power amplifier triggered by an excitation signal. Background Art

[0002] Microwave power amplifiers are an important part of microwave systems. They can amplify weak microwave signals to the required power level, generally at the end of a transmitter, and are widely used in fields such as wireless communication, radar, remote sensing, medical electronics, measurement and control, and electronic countermeasures. With the increasing maturity of the third-generation semiconductor material GaN process, the output power of power amplifiers has also increased significantly. Currently, the output power of a single transistor has exceeded 2 kW. For example, the paper "Design and Implementation of an X-Band High-Power Solid-State Power Amplifier" published by Niu Haijun et al. in 2024 in Communications World.

[0003] Pulse-mode microwave systems are widely used. Pulse-mode radars, transmit-receive time-division electronic countermeasure systems, and burst communication systems are all pulse-mode, which requires the power amplification circuit to work in pulse mode. Hyo-Jong Kim et al. pointed out in the article "An X-Band 100W GaN HEMT Power Amplifier Using a Hybrid Switching Method for Fast Pulse Switching" published in Progress In Electromagnetics Research B, Vol. 78, in 2017 that by using drain bias voltage modulation, higher efficiency, larger output power, higher gain, faster rise time, faster fall time, and flatter gain can be obtained. Therefore, better performance can be obtained by using drain bias voltage modulation.

[0004] It is found in the research that when using the drain bias modulation method, at the moment of applying a microwave excitation pulse and a microwave excitation pulse, if the static current and the dynamic current are not equal, then due to the parasitic inductance in the drain supply path, a drain voltage overshoot will occur. Only in class A operating mode, the static current and the dynamic current are equal, which can avoid the generation of drain voltage overshoot, but the efficiency will be limited to 50% of the theoretical efficiency upper limit. Therefore, in 2021, Fang Wenrao proposed a method for improving the efficiency of a hybrid-class solid-state power amplifier in his doctoral dissertation "Research on Key Technologies of X-Band High-Power Pulse Power Amplifiers", using the method of switching between class B and class A operating modes within a pulse to improve the efficiency while taking into account the low drain voltage overshoot.

[0005] However, the gain of Class B operating mode is different from that of Class A operating mode. Specifically, the gain of Class B operating mode is only one-fourth of that of Class A operating mode. Then, when the input signal power remains unchanged, the switching of the operating mode will cause the gain to be too large, resulting in waveform distortion in Class A operating mode, and further causing the drain voltage overshoot to appear again, while the efficiency decreases. Summary of the Invention

[0006] The object of the present invention is to overcome the problems of low stability or low efficiency of existing power amplifiers, and proposes a method and circuit for improving the overshoot suppression efficiency of power amplifiers triggered by excitation signals.

[0007] To achieve the above object, the present invention adopts the following technical solutions: A method for improving the overshoot suppression efficiency of power amplifiers triggered by excitation signals, comprising the following steps: Before t time 0: The pulse signal generator provides a pulse trigger signal. After the rising edge of the pulse trigger signal is delayed by the second delay circuit, it is sent to the radio frequency signal source; the gate voltage control circuit provides the gate bias voltage of the Class B operating point for the pulse power amplifier. The rising edge of the pulse trigger signal is sent to the second delay circuit through the rising edge detection circuit; the above-mentioned pulse trigger signal sent to the rising edge detection circuit generates a first trigger signal through the rising edge detection circuit; the first trigger signal triggers the drain voltage control circuit to provide the drain bias voltage for the drain of the pulse power amplifier. At t time 0: The rising edge of the pulse trigger signal delayed by the second delay circuit reaches the radio frequency signal source, and the radio frequency signal source starts to generate an excitation signal; The gate voltage control circuit continues to provide the gate bias voltage of the Class B operating point for the pulse power amplifier; Between t time 0 and t time 1: The gate bias voltage and the drain bias voltage of the pulse power amplifier remain unchanged, and both operate in Class B; Between t time 1 and t time 2: The second trigger signal triggers the gate voltage control circuit to adjust the gate bias voltage of the pulse power amplifier, and the gate voltage gradually rises; The operating state of the pulse power amplifier gradually changes from Class B to Class A, and at this time it is in the AB class operating state; Between t time 2 and t time 3: The pulse power amplifier is biased in Class A; The gate voltage of the pulse power amplifier remains unchanged; The drain voltage of the pulse power amplifier gradually drops to 0V.

[0008] Further, when there is no microwave signal input: The pulse signal generator does not generate a pulse trigger signal, and the grid voltage control circuit provides a class B operating point grid bias voltage to the pulse power amplifier, and the pulse power amplifier does not operate.

[0009] Further, at t before time 0: The drain bias voltage of the pulse power amplifier gradually rises from 0V to the required drain bias voltage; At t time 0: The drain bias voltage of the pulse power amplifier has stabilized at the required drain bias voltage; At t time 1: The excitation signal is about to end, and the pulse trigger signal generated by the pulse signal generator reaches the falling edge. After the falling edge of the pulse trigger signal is delayed by the second delay circuit, it is sent to the RF signal source; The falling edge of the pulse trigger signal is sent to the second delay circuit through the falling edge detection circuit; the pulse trigger signal sent to the falling edge detection circuit generates a second trigger signal through the falling edge detection circuit; the second trigger signal triggers the grid voltage control circuit to start adjusting the grid bias voltage of the pulse power amplifier; At t time 2: The grid voltage and drain voltage of the pulse power amplifier are stable, and it is in class A operating state; At t time 3: The grid voltage of the power amplifier starts to drop; The drain voltages of the power amplifier all drop to 0V.

[0010] Further, at t after time 3: The grid voltage control circuit causes the grid voltage of the pulse power amplifier to start dropping back to the grid bias voltage when there is no microwave signal input, waiting for the arrival of the next pulse signal.

[0011] Further, at t At time 2, the pulse power amplifier operates in class A mode. At this time, the current waveform in the class A operating state is symmetric about the quiescent operating point, and the angles of the upper and lower truncation corners are both 120°.

[0012] The power amplifier overshoot suppression efficiency improvement circuit triggered by an excitation signal is used to implement the power amplifier overshoot suppression efficiency improvement method triggered by the excitation signal, and is characterized in that it includes a pulse signal generator, a radio frequency signal source, a control circuit, and a pulse power amplifier; The output end of the pulse signal generator is connected to the input end of the radio frequency signal source and the input end of the control circuit, and the output end of the radio frequency signal source and the output end of the control circuit are connected to the pulse power amplifier; The control circuit includes a drain voltage control circuit and a gate voltage control circuit, and the drain voltage control circuit and the gate voltage control circuit are respectively connected to the pulse power amplifier.

[0013] Further, the control circuit further includes a rising edge detection circuit, a falling edge detection circuit, a first delay circuit, and a second delay circuit; The input ends of the rising edge detection circuit and the falling edge detection circuit are respectively connected to the output end of the pulse signal generator; the output end of the rising edge detection circuit is respectively connected to the input end of the drain voltage control circuit and the input end of the second delay circuit; the output end of the falling edge detection circuit is respectively connected to the input end of the gate voltage control circuit, the input end of the first delay circuit, and the input end of the second delay circuit; the output end of the first delay circuit is connected to the input end of the drain voltage control circuit; the output end of the second delay circuit is connected to the input end of the radio frequency signal source; the output end of the radio frequency signal source is connected to the signal input end of the pulse power amplifier; the output end of the gate voltage control circuit is connected to the gate of the pulse power amplifier, and the output end of the drain voltage control circuit is connected to the drain of the pulse power amplifier.

[0014] Further, the pulse power amplifier switches from class B operating mode to class A operating mode within the microwave pulse signal.

[0015] A power amplifier includes a pulse power amplifier, and also includes the power amplifier overshoot suppression efficiency improvement circuit triggered by the excitation signal. The output end of the radio frequency signal source is connected to the signal input end of the pulse power amplifier; the drain voltage control circuit is connected to the drain of the pulse power amplifier, and the gate voltage control circuit is connected to the gate of the pulse power amplifier.

[0016] Further, the pulse power amplifier is a power amplifier composed of field effect transistors or a power amplifier composed of bipolar transistors.

[0017] Compared with the prior art, the present invention has the following beneficial technical effects: The method for improving the overshoot suppression efficiency of a power amplifier triggered by an excitation signal proposed by the present invention is that the pulse power amplifier operates in Class B with high efficiency in the front part of the microwave excitation signal. A falling-edge detection circuit is used to detect the falling edge of the power amplifier excitation signal. Before the falling edge of the excitation signal arrives, the gate bias voltage is adjusted through a voltage control circuit to change the operating class of the power amplifier, and the gate bias voltage is adjusted to Class A. At the same time, the static operating point position is adjusted, so that the power amplifier operates in a Class A mode with symmetric truncation of the upper and lower waveforms, so that the drain voltage does not generate overshoot when the microwave excitation signal is turned off, and the efficiency is improved at the same time. This solves the problems of efficiency reduction and voltage overshoot caused by output waveform distortion due to different gains of Class A and Class B power amplifiers.

[0018] The method for improving the overshoot suppression efficiency of a power amplifier triggered by an excitation signal proposed by the present invention can solve the problems of waveform distortion caused by different gains during mode switching in existing high-power hybrid pulse power amplifiers, and further lead to instability and efficiency reduction, suppress the voltage overshoot of high-power pulse power amplifiers, avoid breakdown of pulse power amplifiers, and improve the stability of pulse power amplifiers.

[0019] Furthermore, the efficiency can be made closer to the high theoretical efficiency of 78.5% of Class B, showing a certain improvement compared to the existing mode.

[0020] Furthermore, when the bias voltage of the hybrid pulse power amplifier is switched, since the output powers of Class A and Class B are basically the same, the flatness of the output microwave waveform can be maintained while improving the efficiency and stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings described herein are for illustrative purposes only and are not intended to limit the scope of the disclosure of the present invention in any way. In addition, the shapes and proportional dimensions of the components in the drawings are only schematic and are used to assist in understanding the present invention, rather than specifically limiting the shapes and proportional dimensions of the components of the present invention. In the drawings: Figure 1 It is a schematic diagram of the electrical characteristics of a two-stage power amplifier under a pulse signal for the method for improving the overshoot suppression efficiency of a power amplifier triggered by an excitation signal proposed by the present invention.

[0022] Figure 2 It is a schematic diagram of the circuit system of a two-stage power amplifier under a pulse signal for the circuit for improving the overshoot suppression efficiency of a power amplifier triggered by an excitation signal proposed by the present invention.

[0023] Figure 3 It is a schematic diagram of the current waveform and voltage waveform of the Class A mode in the double truncation case in the embodiment of the present invention.

[0024] Figure 4Schematic diagram of the normalized output power and efficiency of Class A mode relative to the traditional Class B mode varying with the truncation angle in the case of double truncation in the embodiments of the present invention. Detailed implementation manners

[0025] In order to enable those skilled in the art of the present technology to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0026] It should be noted that when an element is referred to as being "disposed on" another element, it can be directly on the other element or there may also be a central element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are only for the purpose of illustration and do not represent the only embodiments.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field of the present invention. The terms used herein in the description of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" as used herein includes any and all combinations of one or more of the related listed items.

[0028] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and do not have to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0029] Embodiment 1 This embodiment proposes a method for improving the overshoot suppression efficiency of a power amplifier triggered by an excitation signal, as Figure 1 shown, and specifically includes the following steps: 1] When there is no microwave signal input: The pulse signal generator fails to generate a pulse trigger signal, and the grid voltage control circuit provides a class B operating point bias voltage to the pulse power amplifier. V gb ; The pulse power amplifier does not work; 2] t Before time 0: The pulse signal generator provides a pulse trigger signal; The rising edge of the pulse trigger signal is delayed by the second delay circuit and sent to the RF signal source; The above pulse trigger signal sent to the rising edge detection circuit generates a first trigger signal through the rising edge detection circuit; the grid voltage control circuit continues to provide a class B operating point bias voltage to the power amplifier V gb ; The drain voltage control circuit provides a drain bias voltage to the drain of the pulse power amplifier, and the drain bias voltage of the power amplifier gradually rises from 0V to the required drain bias voltage V dd ; 3] t At time 0: The drain bias voltage of the pulse power amplifier has been stabilized at the required drain bias voltage; The rising edge of the pulse trigger signal delayed by the second delay circuit reaches the RF signal source, and the RF signal source starts to generate an excitation signal; The grid voltage control circuit continues to provide a class B operating point bias voltage to the pulse power amplifier V gb ; 4] t Between time 0 and t time 1: The grid bias voltage and drain bias voltage of the power amplifier remain unchanged and operate in class B; 5] t At time 1: The excitation signal is about to end, and the pulse trigger signal generated by the pulse signal generator reaches the falling edge; The falling edge of the pulse trigger signal is delayed by the second delay circuit and sent to the RF signal source; The falling edge of the above pulse trigger signal sent to the falling edge detection circuit generates a second trigger signal through the falling edge detection circuit, triggering the grid voltage control circuit to start adjusting the grid bias voltage of the power amplifier; the grid voltage of the power amplifier is adjusted from V gb gradually rising to V ga , so that it is biased to class A mode and the static operating point can make the waveform symmetrically truncated up and down; 6] t Between time 1 andt Between two moments: The pulse trigger signal generated by the pulse signal generator reaches the falling edge; The falling edge of the pulse trigger signal is delayed by the second delay circuit and sent to the RF signal source; The falling edge of the above pulse trigger signal sent to the falling edge detection circuit generates a second trigger signal through the falling edge detection circuit, triggering the grid voltage control circuit to start adjusting the amplifier grid bias voltage, and the grid voltage rises from V gb gradually to V ga ; The operating state of the pulse power amplifier gradually changes from class B to class A, and at this time it is in class AB operating state; the amplifier operating mode has class A (360°), class B (180°), and class AB (greater than 180° and less than 360°) according to the conduction angle, t From moment 1 to t When switching from class B to class A (the conduction angle increases from 180° to 360°) between two moments, it is in class AB operating mode; 7] t Moment 2: The grid voltage of the power amplifier stabilizes at V ga , and the drain voltage remains V dd unchanged, being in class A operating state. Since the gains of class A and class B power amplifiers are different, the waveform in class A operating state is truncated simultaneously up and down at this time, and is symmetrical up and down with equal truncation angles. In order to keep the input power unchanged when switching from class B mode to double-truncated class A mode, the angles of the upper and lower truncation angles should be 120°. At this time, the normalized output power and drain efficiency relative to the traditional class B operating mode are 1.22 and 60.90% respectively; 8] t Between moment 2 and t moment 3: The power amplifier is biased in class A; The grid voltage of the power amplifier remains V ga ; The drain voltage of the power amplifier gradually drops from V dd to 0V; 9] t Moment 3: The grid voltage of the power amplifier starts to drop from V ga ; The drain voltage of the power amplifier drops to 0V; 10] t After moment 3: The gate voltage of the power amplifier drops from V ga and recovers to V gb , waiting for the arrival of the next pulse signal.

[0030] The method for improving the overshoot suppression efficiency of the power amplifier triggered by the excitation signal provided in this embodiment is an improved method for suppressing the voltage overshoot and improving the efficiency of the hybrid high-power solid-state pulse power amplifier under the same trigger signal. It aims to solve the problems of low stability or low efficiency caused by different working mode gains of the existing hybrid power amplifier, and can simultaneously obtain the high stability of class A pulse power amplifier and the high efficiency of class B pulse power amplifier. At the same time, it solves the problems of waveform distortion caused by different gains, which in turn reduces the stability and efficiency.

[0031] Embodiment 2 This embodiment provides a circuit for improving the overshoot suppression efficiency of the power amplifier triggered by the excitation signal. From Figure 2 It can be seen that the pulse signal generator simultaneously provides pulse trigger signals to the RF signal source and the pulse power amplifier. The pulse trigger signal is used to trigger the RF signal source to generate an excitation signal, and trigger the drain voltage control circuit of the pulse power amplifier to provide a bias voltage to the drain of the power amplifier, and trigger the gate voltage control circuit to provide the correct bias voltage to the gate of the power amplifier.

[0032] To achieve that the power amplifier operates in class A at the moment when the microwave excitation signal is turned off, it is necessary to judge the moment when the microwave excitation signal is turned off, control the transmission delay of the microwave excitation signal, and accurately control the magnitude of the gate bias voltage to ensure that the gate bias voltage has become the class A bias voltage at or before the moment when the falling edge of the microwave excitation signal reaches the power amplifier. Therefore, in addition to the gate voltage control circuit and the drain voltage control circuit, this circuit also includes a rising edge detection circuit, a falling edge detection circuit, a first delay circuit and a second delay circuit. The input ends of the rising edge detection circuit and the falling edge detection circuit are both connected to the output end of the pulse signal generator.

[0033] The input ends of the rising edge detection circuit and the falling edge detection circuit are respectively connected to the output end of the pulse signal generator; the output end of the rising edge detection circuit is connected to the input end of the drain voltage control circuit and the input end of the second delay circuit; the output end of the falling edge detection circuit is connected to the input end of the gate voltage control circuit, the input end of the first delay circuit and the input end of the second delay circuit; the output end of the first delay circuit is connected to the input end of the drain voltage control circuit; the output end of the second delay circuit is connected to the input end of the RF signal source; the output end of the RF signal source is connected to the signal input end of the pulse power amplifier; the output ends of the gate voltage control circuit and the drain voltage control circuit are connected to the gate and drain of the pulse power amplifier.

[0034] The rising-edge detection circuit is used to detect the rising edge of the pulse signal generated by the pulse signal generator, and when the rising edge of the pulse signal arrives, it outputs a trigger signal to the drain voltage control circuit and the second delay circuit; the falling-edge detection circuit is used to detect the falling edge of the pulse signal generated by the pulse signal generator, and when the falling edge of the pulse signal arrives, it outputs a trigger signal to the gate voltage control circuit, the first delay circuit and the second delay circuit; the gate voltage control circuit and the drain voltage control circuit control the working mode of the pulse power amplifier according to the pulse signal.

[0035] Combined with Figure 1 , the specific working process of the above circuit is described in detail as follows: When there is no microwave signal input: The pulse signal generator does not generate a pulse trigger signal, and the gate voltage control circuit provides a class B operating point bias voltage for the pulse power amplifier V gb ; The pulse power amplifier does not work; t Before time 0: The pulse signal generator provides a pulse trigger signal; The rising edge of the pulse trigger signal is delayed by the second delay circuit and sent to the RF signal source; The above pulse trigger signal sent to the rising-edge detection circuit generates a first trigger signal through the rising-edge detection circuit; the gate voltage control circuit continues to provide a class B operating point bias voltage for the power amplifier V gb ; The drain voltage control circuit provides a drain bias voltage for the drain of the pulse power amplifier, and the drain bias voltage of the power amplifier gradually rises from 0V to the required drain bias voltage V dd ; t At time 0: The drain bias voltage of the pulse power amplifier has been stabilized at the required drain bias voltage; The rising edge of the pulse trigger signal delayed by the second delay circuit arrives at the RF signal source, and the RF signal source starts to generate an excitation signal; The gate voltage control circuit continues to provide a class B operating point bias voltage for the pulse power amplifier V gb ; t Between time 0 and t time 1: The gate bias voltage and drain bias voltage of the power amplifier remain unchanged and operate in class B; t At time 1: The excitation signal is about to end, and the pulse trigger signal generated by the pulse signal generator reaches the falling edge; The falling edge of the pulse trigger signal is delayed by the second delay circuit and sent to the RF signal source; The falling edge of the pulse trigger signal sent to the falling edge detection circuit generates a second trigger signal through the falling edge detection circuit, triggering the grid voltage control circuit to start adjusting the grid bias voltage of the power amplifier; The grid voltage of the power amplifier is adjusted from V gb gradually rising to V ga so that it is biased to class A mode and the static operating point can make the waveform symmetrically truncated up and down; t Between time 1 and t time 2: The falling edge of the pulse trigger signal generated by the pulse signal generator arrives; The falling edge of the pulse trigger signal is delayed by the second delay circuit and sent to the RF signal source; The falling edge of the pulse trigger signal sent to the falling edge detection circuit generates a second trigger signal through the falling edge detection circuit, triggering the grid voltage control circuit to start adjusting the grid bias voltage of the power amplifier. The grid voltage rises from V gb gradually rising to V ga ; The operating state of the pulse power amplifier gradually changes from class B to class A, and it is in class AB operating state at this time; t At time 2: The grid voltage of the power amplifier stabilizes at V ga , and the drain voltage remains V dd unchanged, in class A operating state. Since the gains of class A and class B power amplifiers are different, the waveform in class A operating state is truncated simultaneously up and down at this time, and is symmetric up and down, and the truncation angles are equal. In order to keep the input power unchanged when switching from class B mode to double-truncated class A mode, the angle of α should be 120°. At this time, the normalized output power and drain efficiency relative to the traditional class B operating mode are 1.22 and 60.90% respectively; t Between time 2 and t time 3: The power amplifier is biased in class A; The grid voltage of the power amplifier remains V ga ; The drain voltage of the power amplifier drops from V dd gradually to 0V; t Time point 3: The gate voltage of the power amplifier starts to decrease from V ga and begins to decline; The drain voltage of the power amplifier drops to 0V; t After time point 3: The gate voltage of the power amplifier recovers from V ga the decline to V gb and waits for the arrival of the next pulse signal.

[0036] As Figure 3 shown, due to excessive input power, the current waveform is double - truncated by the maximum and minimum currents of the transistor, forming a double - truncated class - A mode.

[0037] As Figure 4 shown, the drain efficiency and normalized output power of the double - truncated class - A mode increase with the increase of the truncation angle, proving the performance superiority of the present invention. If the input power remains unchanged when switching from class - B mode to double - truncated class - A mode, the truncation angle should be equal to 120° at this time, the normalized output power relative to the traditional class - B working mode is 1.22, and the drain efficiency is 60.90%.

[0038] The above - mentioned embodiments take the power amplifier composed of field - effect transistors as an example, and are equally applicable to the power amplifier composed of bipolar transistors.

[0039] By reading the above description, many embodiments and many applications other than the provided examples will be obvious to those skilled in the art. Therefore, the scope of this teaching should not be determined with reference to the above description, but should be determined with reference to the full scope of the foregoing claims and the equivalents of these claims. For the sake of comprehensiveness, all articles and references, including patent applications and published announcements, are incorporated herein by reference. Omitting any aspect of the subject matter disclosed herein in the foregoing claims is not intended to abandon that subject matter, nor should the applicant be considered not to have considered that subject matter as part of the disclosed inventive subject matter.

[0040] The above content is a further detailed description of the present invention. It cannot be determined that the specific implementation of the present invention is limited to this. For those of ordinary skill in the technical field to which the present invention pertains, without departing from the concept of the present invention, several simple deductions or substitutions can be made, and all should be regarded as falling within the protection scope determined by the claims submitted for the present invention.

Claims

1. A method for improving the efficiency of power amplifier overshoot suppression under excitation signal triggering, characterized in that: The following steps are involved: exist t Before time 0: the pulse signal generator provides a pulse trigger signal, and the rising edge of the pulse trigger signal is delayed by the second delay circuit and then sent to the RF signal source; the gate voltage control circuit provides the pulse power amplifier with a class B operating point gate bias voltage, and the rising edge of the pulse trigger signal is sent to the second delay circuit via the rising edge detection circuit; The pulse trigger signal sent to the rising edge detection circuit generates a first trigger signal through the rising edge detection circuit; the first trigger signal triggers the drain voltage control circuit to provide a drain bias voltage to the drain of the pulse power amplifier; exist t Time 0: After the rising edge of the pulse trigger signal delayed by the second delay circuit reaches the RF signal source, the RF signal source starts to generate an excitation signal; the gate voltage control circuit continues to provide the pulse power amplifier with a Class B operating point gate bias voltage; exist t 0 time to t 1. Between moments: the gate bias voltage and drain bias voltage of the pulse power amplifier remain unchanged, and both operate in Class B. exist t 1 o'clock to t 2. Between moments: the second trigger signal triggers the gate voltage control circuit to adjust the gate bias voltage of the pulse power amplifier, and the gate voltage gradually rises; the working state of the pulse power amplifier gradually changes from class B to class A, and is now in a class AB working state; exist t 2 o'clock to t 3. Between moments: the pulse power amplifier is biased in class A; the gate voltage of the pulse power amplifier remains unchanged; the drain voltage of the pulse power amplifier gradually drops to 0V.

2. The method for improving the overshoot suppression efficiency of a power amplifier triggered by an excitation signal according to claim 1, characterized in that: When there is no microwave signal input: the pulse signal generator does not generate a pulse trigger signal, the gate voltage control circuit provides a class B operating point gate bias voltage to the pulse power amplifier, and the pulse power amplifier does not work.

3. The method for improving the overshoot suppression efficiency of a power amplifier triggered by an excitation signal according to claim 1, characterized in that: exist t Before time 0: the drain bias voltage of the pulse power amplifier gradually rises from 0V to the required drain bias voltage; exist t Time 0: The drain bias voltage of the pulse power amplifier has stabilized to the required drain bias voltage; exist t Moment 1: The excitation signal is about to end, and the pulse trigger signal generated by the pulse signal generator reaches the falling edge. The falling edge of the pulse trigger signal is delayed by the second delay circuit and then sent to the RF signal source; The falling edge of the pulse trigger signal is sent to the second delay circuit via the falling edge detection circuit; The pulse trigger signal sent to the falling edge detection circuit generates a second trigger signal through the falling edge detection circuit; the second trigger signal triggers the gate voltage control circuit to start adjusting the gate bias voltage of the pulse power amplifier; exist t Moment 2: The gate voltage and drain voltage of the pulse power amplifier are stable, and it is in Class A working state; exist t Moment 3: The gate voltage of the power amplifier begins to decrease; the drain voltage of the power amplifier drops to 0V.

4. The method for improving the overshoot suppression efficiency of a power amplifier triggered by an excitation signal according to claim 1, characterized in that: exist t After 3 moments: the gate voltage control circuit causes the gate voltage of the pulse power amplifier to start to drop and return to the gate bias voltage when there is no microwave signal input, waiting for the arrival of the next pulse signal.

5. The method for improving the overshoot suppression efficiency of a power amplifier triggered by an excitation signal according to claim 1, characterized in that: exist t 2. The pulse power amplifier works in Class A mode. At this time, the current waveform in Class A working state is symmetrical about the static working point, and the upper and lower cutoff angles are both 120°.

6. A circuit for improving the efficiency of power amplifier overshoot suppression triggered by an excitation signal, used to implement the method for improving the efficiency of power amplifier overshoot suppression triggered by an excitation signal as described in any one of claims 1 to 5, characterized in that: It includes a pulse signal generator, a radio frequency signal source, a control circuit and a pulse power amplifier; The output end of the pulse signal generator is connected to the input end of the radio frequency signal source and the input end of the control circuit, and the output end of the radio frequency signal source and the output end of the control circuit are connected to the pulse power amplifier; The control circuit comprises a drain voltage control circuit and a gate voltage control circuit, and the drain voltage control circuit and the gate voltage control circuit are respectively connected to the pulse power amplifier.

7. The circuit for improving the efficiency of power amplifier overshoot suppression triggered by an excitation signal according to claim 6, characterized in that: The control circuit also includes a rising edge detection circuit, a falling edge detection circuit, a first delay circuit and a second delay circuit; The input ends of the rising edge detection circuit and the falling edge detection circuit are respectively connected to the output end of the pulse signal generator; the output end of the rising edge detection circuit is respectively connected to the input end of the leakage voltage control circuit and the input end of the second delay circuit; the output end of the falling edge detection circuit is respectively connected to the input end of the gate voltage control circuit, the input end of the first delay circuit and the input end of the second delay circuit; the output end of the first delay circuit is connected to the input end of the leakage voltage control circuit; The output end of the second delay circuit is connected to the input end of the RF signal source; the output end of the RF signal source is connected to the signal input end of the pulse power amplifier; the output end of the gate voltage control circuit is connected to the gate of the pulse power amplifier, and the output end of the drain voltage control circuit is connected to the drain of the pulse power amplifier.

8. The circuit for improving the efficiency of power amplifier overshoot suppression triggered by an excitation signal according to claim 6, characterized in that: The pulse power amplifier switches from the class B operating mode to the class A operating mode within the microwave pulse signal.

9. A power amplifier, comprising a pulse power amplifier, characterized in that: It also includes the circuit described in any one of claims 6-8, wherein the output end of the radio frequency signal source is connected to the signal input end of the pulse power amplifier; the drain voltage control circuit is connected to the drain of the pulse power amplifier, and the gate voltage control circuit is connected to the gate of the pulse power amplifier.

10. A power amplifier according to claim 9, characterized in that: The pulse power amplifier is a power amplifier composed of field effect transistors or a power amplifier composed of bipolar transistors.

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