Amplitude phase modulation out-phase power amplifier

Abstract

The invention relates to the technical field of out-phase power amplifiers, in particular to an amplitude phase modulation out-phase power amplifier which comprises two power amplifier modules connected in parallel, the input ends of the power amplifier modules are connected with an amplitude phase modulation module, and the output ends of the power amplifier modules are connected with a load RL. The power amplifier module comprises a power amplifier, a voltage conversion unit and a susceptance compensation unit which are sequentially connected in the current flowing direction. By introducing the susceptance compensation unit, the efficiency secondary maximum value at a power rollback point is realized, the efficiency of the power amplifier in a rollback interval is integrally improved, furthermore, the voltage conversion unit improves a smaller drain voltage amplitude of the power amplifier to a larger load voltage amplitude, a larger load resistor is allowed to be used, and the power output is further optimized. And secondly, by adopting a voltage-controlled current type power amplifier architecture, a high-frequency communication scene is adapted, the area and efficiency loss caused by a traditional transformer is avoided, the heat loss is remarkably reduced, and the energy utilization rate is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of out-of-phase power amplifiers, and particularly to an amplitude-phase modulation out-of-phase power amplifier. Background Art

[0002] Modern wireless communication systems adopt high-order quadrature amplitude modulation (QAM) and orthogonal frequency division multiplexing (OFDM) technologies to improve spectral efficiency. However, their high peak-to-average power ratio (PAPR) results in a significant decrease in the efficiency of power amplifiers (PAs) at the back-off power point. Traditional out-of-phase power amplifiers (OPAs) synthesize signals by decomposing constant envelope signals. However, it is difficult to apply switched-mode PAs in high-frequency communications. The voltage-controlled current-mode PA has limited equivalent impedance modulation range, resulting in insufficient efficiency improvement. The compensation reactance is not fully utilized during power back-off, and the output power range is limited.

[0003] Therefore, there is an urgent need for a high-efficiency power amplifier architecture to solve the above technical defects. Summary of the Invention

[0004] The purpose of the present invention is to provide an amplitude-phase modulation out-of-phase power amplifier, which is used to solve the problem that the existing out-of-phase power amplifier technical solutions are imperfect, and it is impossible to correctly use the characteristics of voltage-controlled current-mode PAs to form an out-of-phase power amplifier, resulting in insufficient efficiency improvement during power back-off.

[0005] The technical solution of the present invention is realized as follows:

[0006] An amplitude-phase modulation out-of-phase power amplifier includes: two parallel power amplifier modules. The input end of the power amplifier module is connected to an amplitude-phase modulation module, and the output end is connected to a load R L connected, where the amplitude-phase modulation module is used to generate two out-of-phase non-constant envelope control signals from the input signal S in ;

[0007] Wherein, the power amplifier module includes a power amplifier, a voltage conversion unit, and a susceptance compensation unit connected in sequence along the current flow direction. The input end of the power amplifier is connected to the amplitude-phase modulation module and receives the control signal sent by the amplitude-phase modulation module. The voltage conversion unit converts the maximum fundamental voltage of the load into a smaller maximum fundamental voltage of the drain of the power amplifier. The susceptance compensation unit is used to compensate the imaginary part of the equivalent admittance of the output branch of the power amplifier;

[0008] The input end of the voltage conversion unit is connected to the input end of the power amplifier, and the output end is connected to the load R L connected. One end of the compensation unit is connected to the output end of the voltage conversion unit, and the other end is grounded;

[0009] Among them, the voltage conversion unit is an inductor element or a capacitor element, and the compensation unit is an inductor element or a capacitor element. The element types of the voltage conversion unit and the compensation unit in the same power amplifier module are different, and the element types of the two voltage conversion units are different. (It can be deduced without doubt that the element types of the two compensation units are different)

[0010] Optionally, the susceptance compensation unit compensates the imaginary part of the equivalent admittance at the power back-off point, so that the imaginary part of the equivalent admittance of the output branch of the power amplifier is cancelled, and only the real part flows into the load R L 。

[0011] Optionally, the impedance value of the voltage conversion unit is determined according to the back-off power, and is used to amplify the load voltage to a preset multiple, so as to improve the efficiency at the saturation power and the power back-off point.

[0012] Optionally, the power amplifier is a voltage-controlled current-mode class B or class AB power amplifier, adopting a voltage-controlled current-mode PA architecture, adapting to high-frequency communication scenarios, avoiding the area and efficiency losses brought by traditional transformers, and the technical solution is compatible with class B, class AB and class F PAs, expanding the application scenarios.

[0013] Optionally, the output currents at the output ends of the two parallel power amplifier modules are two currents with equal amplitude and opposite phases.

[0014] Optionally, at the power back-off point, the output power is cos 2 (ψc) of the maximum power value, and the back-off power PBO = 20lg(cos(ψc)), where ψc is a preset phase difference angle.

[0015] The beneficial effects of the present invention are:

[0016] By introducing a susceptance compensation unit (for compensating susceptance) at the back end of the power amplifier, the present invention realizes the second maximum value of efficiency at the power back-off point, overall improves the efficiency of the power amplifier in the back-off interval. Further, the voltage conversion unit (voltage regulation module) increases the amplitude of the load voltage, allowing a larger load resistance to be used, and further optimizing the power output.

[0017] Secondly, by adopting a voltage-controlled current-mode power amplifier architecture, it adapts to high-frequency communication scenarios, avoids the area and efficiency losses brought by traditional transformers, significantly reduces heat loss, improves energy utilization rate, and is applicable to high-PAPR communication systems such as 5G / 6G. Description of the Drawings

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required in the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0019] Figure 1 It is a schematic diagram of the power amplifier circuit structure;

[0020] Figure 2 It is a schematic diagram of the voltage - type out - of - phase power amplifier structure;

[0021] Figure 3 It is a schematic diagram of the current - type out - of - phase power amplifier structure;

[0022] Figure 4 It is a schematic diagram of the amplitude - phase modulation out - of - phase power amplifier structure;

[0023] Figure 5 It is a schematic diagram of the circuit equivalent admittance principle;

[0024] Figure 6 It is a schematic diagram of the power amplifier input control signal generation process principle;

[0025] Figure 7 It is a graph of the efficiency - back - off power relationship. Detailed implementation manners

[0026] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments.

[0027] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inside", "outside", etc. are based on the orientation or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0028] A power amplifier (PA) is a device that obtains energy from a DC power supply according to the control of a low - power RF signal and converts it into a high - power RF signal. The PA is usually the module with the largest power consumption in an RF transmitter. The energy obtained by the PA from the DC power supply also generates heat loss during the conversion process. To reduce the heat loss and improve the utilization rate of electric energy, the PA should have a high efficiency.

[0029] Figure 1.(a) shows the classic structure of the PA. The PA is controlled by the control signal V in and obtains energy from the DC voltage source V DD . Part of the energy is output to the load R L , and part of it generates heat loss. M1 in this structure is an N-type field-effect transistor, which can also be replaced by a bipolar transistor to play a role in signal amplification; L d provides a low impedance to the DC, reduces the DC voltage drop, and provides a large impedance to the fundamental wave to increase the gain of the control signal. Figure 1 .(b) Intuitively shows the working principle of the PA, Figure 1 .(c) is the simplified symbol of the PA.

[0030] In the case of increasingly scarce spectrum resources and the requirement for faster data transmission rates, modern wireless communication technologies need to expand the communication frequency to higher frequencies and use complex signal modulation technologies. Higher-order quadrature amplitude modulation (QAM) can achieve high-rate data transmission and improve spectrum utilization efficiency, and orthogonal frequency division multiplexing (OFDM) can alleviate potential severe channel conditions (such as selective fading, interference, and multipath effects) when transmitting broadband signals. Both of these technologies are widely used in the latest high-rate wireless communication systems.

[0031] The use of higher-order QAM and OFDM results in a high peak-to-average power ratio (PAPR), which can reach 8 - 13 dB. This poses strict requirements on the efficiency and linearity of the PA. Traditional PAs (such as Class-B) provide maximum efficiency at the peak signal power level, but much lower efficiency at the mean power level. This requires the study of new PA architectures to improve the efficiency when the output power is backed off to the mean power, thereby improving the energy utilization efficiency and reducing heat loss.

[0032] Most high-rate wireless communication systems adopt non-constant envelope modulation methods such as QAM and OFDM, which can be decomposed into two constant envelope signals. The change in the envelope is reflected in the phase change of the two constant envelope signals. After amplifying these two signals by PAs with the same gain and then summing them, the amplified non-constant envelope signal can be restored. Usually, the phases of the two decomposed constant envelope signals contain +ψ and -ψ respectively, and ψ is between. These two constant envelope signals are called in-phase signals, ψ is called the in-phase angle, and the envelope size of the non-constant envelope signal is reflected in cos(ψ), which is the ratio of the current envelope amplitude to the maximum envelope amplitude. The in-phase power amplifier needs to adopt a certain form of power combiner to improve the efficiency.

[0033] The above elaborates on the relevant technical background of the existing power amplifier.

[0034] Secondly, before elaborating on the solution of this application, it is necessary to elaborate on the existing conventional technologies to facilitate the understanding of the solution of this embodiment and the corresponding technical effects.

[0035] Existing technology solution one: As Figure 2 shown, the out-of-phase voltage sources Ve jψ and Ve -jψ output by two sub-power amplifiers drive the current-mode power synthesizer. The two transformers in the power synthesizer superimpose the two voltages to 2Vcos(ψ), that is, the output current is From this, it can be obtained that the equivalent admittances at the left ends of the upper and lower transformers respectively contain inductive and capacitive susceptances, and this part of the susceptance does not consume the power of the fundamental wave output by the PA. It can be known from Fourier transform that the current flowing through the equivalent susceptance will be added to the current of the conductance part, and its amplitude is in a certain proportion to the DC magnitude provided by the voltage source of the sub-power amplifier. From the efficiency relationship, the efficiency form at this time is similar to that of a Class-B PA. In order to improve the efficiency during power back-off, capacitive and inductive compensation susceptances, that is, C ψc and C ψc can be added to the left ends of the upper and lower transformers respectively to compensate for the inductive and capacitive susceptances in the equivalent admittances at the upper and lower transformers near the saturated output power and at the back-off power. At these two power points, the fundamental wave current flowing out of the sub-power amplifier all flows into the load, and the DC current is correspondingly reduced, and the DC power consumption is reduced. Therefore, the efficiency reaches the maximum value at these two power points.

[0036] The disadvantages of existing technology solution one are that there are several disadvantages that limit its practical application and efficiency improvement: (1) When the communication frequency increases, it is difficult to use a switched-mode PA, and a voltage-controlled current-mode PA is used. It is difficult to maintain the form of Ve jψ and Ve -jψ at the PA output, it is difficult to modulate the susceptance as expected, and it is difficult to improve the efficiency at the back-off power point; (2) One transformer needs to be implemented with two inductors. The inductor needs to occupy a much larger chip area than transistors and capacitors. At the same time, the Q value of the on-chip inductor is low, which will consume a large amount of power and reduce the efficiency of the out-of-phase power amplifier.

[0037] Existing technology solution two: Considering that when the communication frequency increases, it is difficult to use a switched-mode PA for power amplification. At this time, a voltage-controlled current-mode PA is usually used for power amplification, which has spawned a new technology solution two to establish a suitable out-of-phase power amplifier structure. Its structure and current relationship are as Figure 3 shown. In the current-mode OPA, the equivalent impedances at the left sides of the current merging points of the upper and lower sub-power amplifiers respectively contain capacitive and inductive reactances. Therefore, inductive and capacitive reactances are respectively used for compensation, that is, L ψc and C ψc, let it compensate the capacitive and inductive reactances in the equivalent impedances of the two sub - power amplifiers near the saturated output power and at the back - off power respectively. At the power back - off point, the current is reduced by a certain proportion, so that the fundamental voltage magnitude output by the sub - power amplifier is equal to the voltage of the DC voltage source, and the DC current output by the DC voltage source is also reduced by the same proportion. Therefore, the maximum efficiency is achieved both near the saturated output power and at the back - off power.

[0038] The disadvantages of the existing technical solution two are as follows: This technical solution takes into account the technical status that the voltage - controlled current - type PA is more suitable for the improvement of communication frequency, but there are several problems: (1) When the phase difference angle corresponding to the back - off power is ψ c , the range of the phase difference angle ψ of the power after signal combination is [0, ψ c , and the range of the impedance modulated by the phase difference angle ψ is Therefore, the range of the output power modulated by the phase difference angle has not been utilized, resulting in a smaller power range output by the load; (2) From the relationship between current and efficiency, when the output current is reduced by a certain proportion, the DC current output by the DC voltage source is also reduced by the same proportion, and the efficiency will reach the maximum value again. In this process, the compensating reactance does not play a role.

[0039] Embodiment 1:

[0040] In view of the defects mentioned in the above - mentioned existing technical solution one and existing technical solution two, this embodiment provides an amplitude - phase - modulated out - of - phase power amplifier, as Figure 4 shown, including: two parallel power - amplifier modules, the input ends of the power - amplifier modules are connected to an amplitude - phase modulation module, and the output ends are connected to a load R L connected, where the amplitude - phase modulation module is used to generate two out - of - phase non - constant - envelope control signals from the input signal S in ;

[0041] Among them, each power - amplifier module includes a power amplifier, a voltage conversion unit, and a susceptance compensation unit connected in sequence along the current flow direction. The input end of the power amplifier is connected to the amplitude - phase modulation module and receives the control signal sent by the amplitude - phase modulation module. The voltage conversion unit converts the maximum fundamental voltage of the load into a smaller maximum fundamental voltage of the drain of the power amplifier. The susceptance compensation unit is used to compensate the imaginary part of the equivalent admittance of the output branch of the power amplifier;

[0042] The input end of the voltage conversion unit is connected to the input end of the power amplifier, and the output end is connected to the load R L connected. One end of the compensation unit is connected to the output end of the voltage conversion unit, and the other end is grounded;

[0043] Among them, the voltage conversion unit is an inductive element or a capacitive element, and the compensation unit is an inductive element or a capacitive element. The element types of the voltage conversion unit and the compensation unit in the same power amplifier module are different. Given that the element types of the two voltage conversion units are different, it can be deduced without doubt that the element types of the two compensation units are different.

[0044] Among them, Figure 4 A specific structure of the amplitude-phase modulation out-of-phase power amplifier is given. That is, the voltage conversion unit in the upper power amplifier module is a capacitive element (capacitive susceptance), and the compensation unit is an inductive element (inductive susceptance); the compensation unit in the lower power amplifier module is a capacitive element (capacitive susceptance), and the voltage conversion unit is an inductive element (inductive susceptance).

[0045] In Figure 4 the amplitude-phase modulation out-of-phase power amplifier disclosed, the fundamental currents I ψ and I -ψ output by the two power amplifiers (PAs), after being shunted to the compensation units +jX C and -jX C in the susceptance compensation unit, the remaining out-of-phase currents Ie jψ and Ie -jψ flow into the output load R L and the output voltage is 2IR L cos(ψ). The out-of-phase currents modulate the equivalent susceptance of each branch; the voltage conversion unit (voltage regulation module) -jX Z and +jX Z amplify the maximum value of the fundamental voltage at the drain of the PA (output terminal of the power amplifier) by a certain multiple to 2IR L , thereby improving the efficiency of the saturation power and the back-off power point. The amplification multiple, X Z and X C are all determined by the designed back-off power. From the above, the form of the currents output by the two power amplifiers (PAs) can be determined, that is, I ±ψ = I(cos(ψ) ± j(sin(ψ) - cos(ψ) × K)), where K is determined by the back-off power and I is a constant. The fundamental current output by the PA must conform to the form of I ±ψ . In the amplitude-phase modulation module, according to the form of I ±ψ , the nature of the gain in the PA, and the quality factors of the capacitors and inductors in the circuit, the input signal S in is generated into two out-of-phase non-constant envelope PA control signals, which are amplified by the PA and output currents with the form of I ±ψ .

[0046] At the back-off power point, I ψ and I -ψThe equivalent capacitive and inductive susceptances corresponding to the branch are compensated by the shunt inductive and capacitive susceptances respectively, and the fundamental current I output by the PA ψ and I -ψ only retain the real parts (the susceptance compensation unit compensates the imaginary part of the equivalent admittance at the power back-off point to cancel the imaginary part of the equivalent admittance of the power amplifier output branch), and all flow into the output load. Due to the presence of the voltage regulation module, the output voltage can be increased by a certain multiple. Therefore, the output load can be increased, thereby increasing the power output by the real part of the current. At this time, the maximum efficiency is reached at the back-off power point.

[0047] Secondly, when constructing the current-mode OPA (out-of-phase power amplifier) architecture, reactance compensation and susceptance compensation can be adopted. If reactance compensation is used, the power amplifier needs to actively output a specific form of voltage. However, in actual integrated circuit technology, whether it is a MOS field-effect transistor or a BJT bipolar junction transistor, what they actively output is current, and the voltage is presented after the current passes through an impedance. Therefore, using reactance compensation will violate this causality. Therefore, this patent innovatively adopts a susceptance-type compensation scheme to construct a current-mode OPA.

[0048] As Figure 5 shown, at the two equivalent points on the right, two currents Ie jψ and Ie -jψ with equal amplitude and opposite phase flow into the load and provide output power for the load. At the same time, the equivalent admittances Y ψ1 and Y -ψ1 of the two equivalent points on the right are modulated. When ψ = ψc, the output power is cos 2 (ψc) of the maximum power value, that is, the power back-off PBO = 20lg(cos(ψc)). At this power point, the imaginary parts of the equivalent admittances Y ψ1 and Y -ψ1 need to be compensated, and inductive and capacitive susceptances with magnitudes of need to be added respectively. Thus, the equivalent admittances Y ψ and Y -ψ of the two equivalent points on the left can be obtained, and the forms of the PA output currents I ψ and I -ψ can also be obtained.

[0049] Embodiment 2:

[0050] Based on the amplitude-phase modulation out-of-phase power amplifier structure disclosed in Embodiment 1, the voltage regulation technology and the efficiency normalization technology principle are further elaborated:

[0051] As Figure 5As shown, the fundamental current output by the two sub-power amplifiers flows into the output impedance to generate output power. When the output power backs off to the power back-off point, for example, when the power is backed off by 12 dB, the out-of-phase angle ψc of the compensating susceptance is 75.5°. At this time, the value of X C is much smaller than that of R L . At the output power saturation point, the PA output currents I ψ and I -ψ are much larger than the value of the load output current. At this time, the power provided by the DC voltage source is very large. That is to say, the efficiency at this time will be much lower than the theoretical efficiency of class B PA; at the power back-off point, the power provided by the PA DC voltage source reaches the minimum value, and the efficiency will reach a maximum value at this time. This efficiency is the same as the maximum efficiency near the saturation point, that is, the efficiency of the circuit reaches the maximum value again. However, the DC current amplitude of the voltage source is too large at this time, and this efficiency will also be much lower than the theoretical saturation efficiency of class B PA.

[0052] Based on the above analysis, the technical solution creatively uses Figure 5 the inductor and capacitor corresponding to the reactance value of ±jX Z for voltage regulation. The functions of the voltage-regulating inductor and capacitor are to adjust the maximum value of the fundamental voltage at the right end of the device to a certain multiple of V DD and make the maximum value of the voltage at the left end less than or equal to V DD . These limitations can determine the device values of the voltage-regulating inductor and capacitor, and the magnification factor is determined by the back-off power. The use of the voltage-regulating device can make the amplitude of the fundamental voltage of the output load greater than a certain multiple of V DD . Therefore, the load resistance can be increased, thereby increasing the saturation output power. Therefore, the efficiency near the saturation power point and the back-off power point can be increased in the same proportion and normalized to the theoretical maximum value of class B PA.

[0053] Example 3:

[0054] Based on Example 2, this example further elaborates on the modulation principle of the input signal of the power amplifier (PA) in the amplitude-phase modulation out-of-phase power amplifier:

[0055] The form of the PA output current has been described above and can be re-expressed as I(ψ)e jP(ψ) and I(ψ)e -jP(ψ) , where I(ψ) represents the amplitude of I ±ψ , and ±P(ψ) represents the phase of I ±ψ . From this form, the processing technology of the PA input signal is derived, that is, the control signal input to the PA should be amplitude- and phase-modulated according to the form of the output current. The MOS field-effect transistor plays an amplifying role in the PA. When the MOS transistor is in the amplification region, the control voltage input to the PA is converted into current at a certain ratio. This conversion ratio is also called the transconductance and can be represented by g mIt is shown that the MOS transistor can be equivalent to a voltage-controlled current source. Thus, by dividing the form of the PA output current by the transconductance, the form of the PA control voltage can be obtained, that is and

[0056] However, considering that the transconductance of the MOS is non-linear with respect to the input signal and the drain voltage, and the control signal input to the PA first decreases and then increases, and its amplitude reaches the minimum value at the phase difference angle corresponding to the power back-off point, which will result in a very small gain, that is, a very small transconductance. Therefore, the non-linearity of the transconductance must be considered, and the amplitude of the input voltage is increased near the power back-off point to increase the transconductance. The compensation for non-linearity only needs to compensate the voltage amplitudes of the two sub-power amplifiers. Let the form of this amplitude compensation be C(ψ), then the form of the PA input control signal at this time is and C(ψ) can be obtained by continuously fitting with Bessel curves or by continuously optimizing the parameters of the Gaussian function. This form should be normalized to the voltage range in which the MOS transistor operates. Let The maximum value of is V smax After considering the bias voltage, the maximum value of the PA input control signal is V GSmax Let Then the final form of the PA input control signal is F(ψ)e jp(ψ) and F(ψ)e -jP(ψ) . Figure 6 Fig. shows the processing process of the PA input signal. In this scheme, cos(ωt) is not marked for simplicity of formula expression, and this term is illustrated with the fundamental wave.

[0057] Secondly, it should be noted that when the communication frequency is relatively high, voltage-controlled current type PAs are widely used. Class B PAs balance efficiency and linearity and are the preferred power amplifier type in this architecture. This architecture is also applicable to Class AB PAs. Only by substituting the ratio of the fundamental wave current amplitude to the DC current amplitude output by the Class AB PA into the efficiency analysis can it be normalized to the saturation efficiency value of Class AB. When the communication frequency is relatively low, Class B power amplifiers can adopt over-drive technology and harmonic load impedance modulation technologies, such as Class F power amplifiers with third-harmonic impedance modulation. These technologies can improve the efficiency at the saturated output of the PA, and at this time, the overall efficiency of the APMOPA, including the back-off efficiency, is also correspondingly improved.

[0058] As an implementation case, the two sub-power amplifiers in this case adopt Class B PAs, and at the same time adopt the APMOPA architecture and signal modulation scheme of this technology, and Figure 7The relationship between the efficiency and the back-off power is shown. For comparison, the relationship between the efficiency of Class B PA without using the technical solution of the present invention and the back-off power is shown. It can be found that at a power back-off of 12 dB, the efficiency of the present technical solution is significantly improved compared with that of Class B PA, and the maximum value of the efficiency appears again. At the same time, the overall efficiency between the saturation power and the back-off power is also significantly improved. The voltage-controlled current-mode PA architecture is adopted to adapt to high-frequency communication scenarios and avoid the area and efficiency losses caused by traditional transformers. The technical solution is compatible with Class B, AB, and F PA, expanding the application scenarios.

[0059] The amplitude-phase modulation out-of-phase power amplifier architecture and a series of technical solutions proposed in this embodiment can achieve the maximum value of the efficiency again at the back-off power, thereby improving the efficiency between the saturation output power and the back-off power as a whole. This solution can well solve the situation that the current communication system has a high working frequency, a large PAPR, and a low efficiency at the average output power point.

[0060] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution of the present invention and its inventive concept, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A magnitude-phase modulation out-of-phase power amplifier, characterized in that, Including: Two parallel power amplifier modules, the input ends of the power amplifier modules are connected to the amplitude and phase modulation module, and the output ends are connected to the load R L wherein the amplitude and phase modulation module is used to generate two out-of-phase non-constant envelope control signals from the input signal S in ​ Among them, the power amplifier module includes a power amplifier, a voltage conversion unit, and a susceptance compensation unit connected in sequence along the current flow direction. The input end of the power amplifier is connected to the amplitude-phase modulation module and receives the control signal sent by the amplitude-phase modulation module. The voltage conversion unit converts the maximum fundamental voltage of the load into a smaller maximum fundamental voltage of the drain of the power amplifier. The susceptance compensation unit is used to compensate the imaginary part of the equivalent admittance of the output branch of the power amplifier; The input end of the voltage conversion unit is connected to the input end of the power amplifier, and the output end is connected to the load R L One end of the compensation unit is connected to the output end of the voltage conversion unit, and the other end is grounded; Among them, the voltage conversion unit is an inductor element or a capacitor element, and the compensation unit is an inductor element or a capacitor element. The element types of the voltage conversion unit and the compensation unit in the same power amplifier module are different, and the element types of the two voltage conversion units are different.

2. The amplitude-phase modulation out-of-phase power amplifier according to claim 1, wherein The susceptance compensation unit compensates the imaginary part of the equivalent admittance at the power back-off point, so that the imaginary part of the equivalent admittance of the output branch of the power amplifier is cancelled, and only the real part flows into the load R L .

3. The amplitude-phase modulation out-of-phase power amplifier according to claim 2, wherein The impedance value of the voltage conversion unit is jointly determined according to the back-off power and the output load impedance, and is used to amplify the load voltage to a preset multiple, thereby improving the efficiency at the saturation power and the back-off power point.

4. The amplitude-phase modulation out-of-phase power amplifier according to claim 1, characterized in that, The power amplifier is a voltage-controlled current-mode class B or class AB power amplifier.

5. The amplitude-phase modulation out-of-phase power amplifier according to claim 3, wherein The output currents at the output ends of the two parallel power amplifier modules are two currents with equal amplitude and opposite phases.

6. The amplitude-phase modulation out-of-phase power amplifier according to claim 5, characterized in that At the power back-off point, the output power is cos 2 (ψc) of the maximum power value, and the back-off power PBO = 20lg(cos(ψc)), where ψc is the preset phase difference angle.

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