Amplifier linearization design verification method and storage medium

Compensating the nonlinear amplifier circuit through negative impedance compensation technology solves the trade-off between efficiency and distortion of traditional amplifiers, achieving higher linearity and lower nonlinear distortion, improving the reliability and flexibility of the circuit.

CN119761289AActive Publication Date: 2025-04-04SUZHOU LAIR MICROWAVE INC
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Patent Information

Application Number
CN202411877449.6
Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Filing Date
2024-12-19
Publication Date
2025-04-04
Estimated Expiration
2044-12-19

AI Technical Summary

Technical Problem

While achieving high efficiency and low distortion, existing amplifiers have problems of high complexity, high cost and sensitivity to environmental changes, especially in traditional feedback systems, where nonlinear distortion is difficult to completely eliminate.

Method used

The nonlinear amplifier circuit is compensated through negative impedance compensation technology, which improves closed-loop gain and linearity, reduces nonlinear distortion, and verifies the effect of linear design by analyzing the total harmonic distortion and intermodulation distortion.

Benefits of technology

It realizes the improvement of the linearity and closed-loop gain of the amplifier, reduces nonlinear distortion, simplifies the circuit structure, and improves the reliability and flexibility of the circuit.

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Abstract

The invention discloses an amplifier linearization design verification method and a storage medium, a non-linear amplifier circuit is compensated by negative impedance compensation, so that the closed-loop gain and linearity of the non-linear amplifier circuit are improved, the non-linear distortion of an amplifier is reduced, and meanwhile, the required devices are few, and the cost is low. The overall reliability of the circuit is improved; by analyzing the total harmonic distortion and the intermodulation distortion of the linear amplifier circuit, the relative distortion level of each harmonic component of the linear amplifier circuit can be clearly expressed, the complexity of the whole amplifier circuit is reduced, the flexibility of building the amplifier circuit is improved, and the application range of the amplifier circuit is widened. And the applicability of the amplifier linearization design verification method is improved.
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Description

Technical Field

[0001] The present invention relates to the technical field of signal circuits, and in particular to an amplifier linearization design verification method and a storage medium. Background Art

[0002] When there is an amplifier in a signal transmission system, it is often necessary to strike a balance between amplifier efficiency and distortion. One way to achieve both high amplifier efficiency and minimal distortion is to linearize the amplifier.

[0003] There are many traditional methods to achieve amplifier linearization, such as feedback, pre-distortion and feedforward. The main disadvantages of these traditional methods are high complexity, high cost, increased sensitivity of the amplifier to environmental changes (such as temperature), and reduced amplifier output power.

[0004] In traditional feedback systems, the limited loop gain of the amplifier makes it impossible to completely eliminate its nonlinearity. Therefore, it is an urgent problem to study other linearization technologies to improve the linearity of the amplifier under the traditional feedback topology. Summary of the invention

[0005] In order to overcome the above shortcomings, the purpose of the present invention is to provide an amplifier linearization design verification method and a storage medium, which compensates the nonlinear amplifier circuit by utilizing negative impedance compensation, thereby improving the closed-loop gain and linearity of the nonlinear amplifier circuit, thereby reducing the nonlinear distortion of the amplifier. At the same time, fewer devices are required, thereby improving the overall reliability of the circuit; by analyzing the total harmonic distortion and intermodulation distortion of the linearized amplifier circuit, the relative distortion level of each harmonic component of the linearized amplifier circuit can be clearly expressed, and the complexity of the entire amplifier circuit is reduced, and the flexibility of building the amplifier circuit is improved, thereby improving the applicability of the amplifier linearization design verification method.

[0006] In order to achieve the above purpose, the technical solution adopted by the present invention is: a radio frequency amplifier linearization design and verification method, comprising: Acquire first node data of an inverting input terminal of an ideal amplifier in a feedback amplifier circuit and second node data of an inverting output terminal of a non-ideal amplifier, and calculate an error term according to the first node data and the second node data; Calculate negative impedance compensation according to the error term, and establish a linear amplifier model according to the negative impedance compensation and feedback amplification circuit; Obtain a first signal expression, calculate a first output signal of the linear amplifier according to the secondary transfer characteristic of the nonlinear amplifier and the first signal expression, obtain third node data of the inverting end of the amplifier, and obtain a first input signal of the inverting end of the amplifier according to the third node data, the first signal expression, and the first output signal; Calculate a second output signal of the amplifier according to the first input signal, and calculate a first input voltage power and a first total harmonic distortion according to the second output signal; A second input voltage power and a second total harmonic distortion of the circuit of the nonlinear amplifier are obtained, and the second input voltage power and the second total harmonic distortion, the first total harmonic distortion and the second total harmonic distortion are compared.

[0007] In this method, the first node data of the linear amplifier and the second node data of the nonlinear amplifier are calculated, which is conducive to calculating the error term between the linear amplifier and the nonlinear amplifier, and the negative impedance compensation required by the nonlinear amplifier can be calculated through the error term, and then the linear amplifier circuit can be designed according to the nonlinear amplifier and the negative impedance compensation; by calculating the first input voltage power table and the first total harmonic distortion of the linear amplifier circuit, and comparing the first input voltage power with the second input voltage power, and comparing the first total harmonic distortion with the second total harmonic distortion, the difference between the linear amplifier circuit for which negative impedance design is performed on the radio frequency amplifier circuit and the circuit for which negative impedance design is not performed is obtained, thereby verifying the effect of negative impedance design on the radio frequency amplifier circuit.

[0008] In some implementations, obtaining the first signal expression includes: inputting a voltage to an inverting terminal of an amplifier in an amplifier linearization model, and the first signal expression is an assumed expression of the voltage.

[0009] In this method, a voltage is driven into the inverting terminal of the linear amplifier to calculate the first input voltage power and the first total harmonic distortion of the linear amplifier, thereby verifying the influence of negative impedance compensation on the nonlinear amplifier circuit in terms of input voltage power and total harmonic distortion.

[0010] In some embodiments, the amplifier linearization design verification method also includes: obtaining a third input voltage power and a third total harmonic distortion of an actual circuit of the linearized amplifier, and comparing the first input voltage power and the third input voltage power, the first total harmonic distortion and the third total harmonic distortion, the second input voltage power and the third input voltage power, the second total harmonic distortion and the third total harmonic distortion.

[0011] In this method, the first input voltage power is compared with the third input voltage power, and the first total harmonic distortion is compared with the third total harmonic distortion, which is conducive to verifying the first input power and the first total harmonic distortion calculated by the formula, and then determining the accuracy of the first input power and the first total harmonic distortion calculated by the formula, and inferring the accuracy and applicability of the formula; the second input voltage power table is compared with the third input voltage power, and the second total harmonic distortion is compared with the third total harmonic distortion, which is used to determine the actual difference between the linear amplifier circuit and the nonlinear amplifier circuit during operation.

[0012] In some embodiments, the amplifier linearization design verification method also includes: obtaining a second signal expression, calculating a third output signal of the linearized amplifier based on the secondary transmission characteristics of the nonlinear amplifier and the second signal expression, obtaining fourth node data of the inverting end of the amplifier, and obtaining a second input signal of the inverting end of the amplifier based on the fourth node data, the second signal expression, and the third output signal.

[0013] In this method, the second signal expression is used to calculate other aspects of the linear amplifier circuit data for comparison with the actual circuit, thereby verifying the nonlinear amplifier circuit after negative impedance compensation.

[0014] In some implementations, obtaining the second signal expression includes: inputting an equal-amplitude dual-tone signal into an inverting terminal of a linear amplifier, and the second signal expression is an assumed expression of the equal-amplitude dual-tone signal.

[0015] In this method, by inputting an equal-amplitude dual-tone signal at the inverting end of the linear amplifier, the equal-amplitude power and intermodulation distortion of the linear amplifier can be calculated, and then the influence of negative impedance compensation on the nonlinear amplifier circuit can be verified from the aspect that the equal-amplitude power and intermodulation are true.

[0016] In some implementations, the fourth output signal is calculated according to the second input signal, and the first equal-amplitude power and the first intermodulation distortion are calculated according to the amplifier output signal.

[0017] In this method, the first equal-amplitude power and the first intermodulation distortion of the linear amplifier are calculated, which is helpful to verify the influence of negative impedance compensation on the nonlinear amplifier circuit from the aspect that the equal-amplitude power and intermodulation are true.

[0018] In some embodiments, the amplifier linearization design verification method further includes: obtaining a second equal-amplitude power and a second intermodulation distortion of the circuit of the nonlinear amplifier, and comparing the first equal-amplitude power and the second equal-amplitude power, the first intermodulation distortion and the second intermodulation distortion.

[0019] In this method, by comparing the first equal-amplitude power and the second equal-amplitude power, and comparing the first intermodulation power and the second intermodulation power, the difference between the linearized amplifier circuit with negative impedance design for the RF amplifier circuit and the circuit without negative impedance design is obtained, thereby verifying the effect of negative impedance design for the RF amplifier circuit.

[0020] In some embodiments, the amplifier linearization design verification method further includes: obtaining a third equal-amplitude power and a third intermodulation distortion of an actual circuit of the linearized amplifier, and comparing the first equal-amplitude power and the third equal-amplitude power, the first intermodulation distortion and the third intermodulation distortion, the second equal-amplitude power and the third equal-amplitude power, the second intermodulation distortion and the third intermodulation distortion.

[0021] In this method, the first equal-amplitude power is compared with the third equal-amplitude power, and the first intermodulation distortion is compared with the third intermodulation distortion, which is conducive to verifying the first input power and the first intermodulation distortion calculated by the formula, and then determining the accuracy of the first input power and the first intermodulation distortion calculated by the formula, and inferring the accuracy and applicability of the formula; the second equal-amplitude power table is compared with the third equal-amplitude power table, and the second intermodulation distortion is compared with the third intermodulation distortion, which is used to determine the actual difference between the linear amplifier circuit and the nonlinear amplifier circuit during operation.

[0022] In some implementations, the first input voltage power includes: signal fundamental power, second harmonic power, and third harmonic power; the first constant amplitude power includes: constant amplitude fundamental power and third-order intermodulation power.

[0023] In this method, by comparing the signal fundamental power, second harmonic power and third harmonic power, the difference between the nonlinear amplifier circuit, the linear amplifier circuit model and the actual linear amplifier circuit is confirmed, thereby completing the verification of the linear design of the amplifier and confirming the reliability and accuracy of the verification result; by comparing the equal-amplitude fundamental power and third-order intermodulation power, the difference between the nonlinear amplifier circuit, the linear amplifier circuit model and the actual linear amplifier circuit is confirmed, thereby completing the verification of the linear design of the amplifier and confirming the reliability and accuracy of the verification result.

[0024] A storage medium, characterized in that a computer program is stored in the storage medium, and the computer program is used to implement the above method when it is executed.

[0025] The beneficial effect of the present invention is that by utilizing negative impedance compensation to compensate for the nonlinear amplifier circuit, the closed-loop gain and linearity of the nonlinear amplifier circuit are improved, thereby reducing the nonlinear distortion of the amplifier. At the same time, fewer devices are required, thereby improving the overall reliability of the circuit; by analyzing the total harmonic distortion and intermodulation distortion of the linearized amplifier circuit, the relative distortion level of each harmonic component of the linearized amplifier circuit can be clearly expressed, and the complexity of the entire amplifier circuit is reduced, the flexibility of building the amplifier circuit is improved, and the applicability of the amplifier linearization design verification method is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of a flow chart of an amplifier linearization design verification method according to an embodiment of the present invention; Figure 2 A schematic diagram of a non-ideal amplifier circuit of an amplifier linearization design verification method according to an embodiment of the present invention; Figure 3 A schematic diagram of an ideal amplifier circuit of an amplifier linearization design verification method according to an embodiment of the present invention; Figure 4 A linearized amplifier circuit model after negative impedance compensation in an amplifier linearization design verification method according to an embodiment of the present invention; Figure 5 A schematic diagram of negative impedance in a nonlinear amplifier circuit of an amplifier linearization design verification method according to an embodiment of the present invention; Figure 6 A schematic diagram of a linear amplifier circuit of an amplifier linearization design verification method according to an embodiment of the present invention; Figure 7 A schematic diagram of an actual circuit of a linear amplifier according to an amplifier linearization design verification method according to an embodiment of the present invention; Figure 8 A schematic diagram of total harmonic distortion simulation of a linear amplifier according to an amplifier linearization design verification method according to an embodiment of the present invention; Fig. 9 A schematic diagram of intermodulation distortion simulation of a linear amplifier according to an amplifier linearization design verification method according to an embodiment of the present invention; Fig.10 A schematic diagram of amplifier gain comparison of an amplifier linearization design verification method according to an embodiment of the present invention; Fig.11 A frequency response diagram of an amplifier linearization design verification method according to an embodiment of the present invention; In the figure: A, linearized fundamental power; B, nonlinear fundamental power; C, linearized second harmonic power; D, nonlinear second harmonic power; E, nonlinear third harmonic power; F, linearized third harmonic power; G, linearized fundamental power; H, nonlinear fundamental power; I, nonlinear third-order intermodulation power; J, linearized third-order intermodulation power. DETAILED DESCRIPTION

[0027] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0028] Combined with Figure 1 To Attachment Figure 4 As shown, the present invention provides an amplifier linearization design verification method, comprising: S100: Obtain first node data of the inverting input terminal of an ideal amplifier in a feedback amplifier circuit and second node data of the inverting output terminal of a non-ideal amplifier, and calculate an error term according to the first node data and the second node data.

[0029] For example, in conjunction with Figure 2 and attached Figure 3 , for the linear amplifier circuit, that is, the linear amplifier circuit, its input impedance , Output Impedance , open loop gain , Input current , its closed-loop gain A is: ; in, and are the input voltage and output voltage of the amplifier, respectively. , , G1 is the conductivity of resistor R1, G2 is the conductivity of resistor R2, and the first node data is: ; For practical amplifiers with finite or nonlinear open-loop gain, due to and , its inverting terminal node is: ; in, is the amplifier inverting input voltage, that is: ; The second node data is sorted as follows: ; There is an error term between the first node data and the second node data: , the error term is the error between the linear amplifier circuit and the nonlinear amplifier circuit.

[0030] S200: Calculate negative impedance compensation according to the error term, and establish a linear amplifier model according to the negative impedance compensation and feedback amplification circuit.

[0031] In order to eliminate the error term, it is necessary to add , which is equivalent to adding a negative impedance to the inverting input of the actual nonlinear amplifier circuit. , negative impedance for: , used to linearize the nonlinear amplifier circuit.

[0032] S300: Obtain a first signal expression, calculate a first output signal of the linear amplifier according to the secondary transfer characteristics of the nonlinear amplifier and the first signal expression, obtain third node data of the inverting end of the amplifier, and obtain a first input signal of the inverting end of the amplifier according to the third node data, the first signal expression, and the first output signal.

[0033] For example, in conjunction with Figure 4 , the input signal is voltage , set the voltage The first signal expression is: ; It represents the input signal at the reverse end of the input amplifier, which includes the feedback signal from the output end, and therefore contains the DC component, fundamental wave and other harmonics. is the DC component of the inverting input signal, is the fundamental wave of the inverting input signal, It is the nth harmonic of the inverting input signal.

[0034] When the input signal amplitude of the inverting terminal of the amplifier is low enough, the parasitic parameters such as the lead inductance in the amplifier can be ignored, and the output signal can be expressed by the Taylor series expansion. Considering the quadratic transmission characteristics of the nonlinear amplifier and the actual influence of the output signal, the Taylor series is only expanded to the second order, that is, the first output signal for: ; in, is the fundamental wave of the amplifier output signal, is the nth harmonic of the amplifier output signal.

[0035] The node at the inverting end of the amplifier is: ,when hour, , simplify the third node data to get: ; in is the input signal of the amplifier, and its expression is: , Indicates the amplitude of the input signal.

[0036] Since the amplifier operates at RF, the DC component can be ignored to simplify the calculation. To determine the fundamental coefficient of the inverting input signal , the input signal The first signal expression and the first output signal Substitute the third node data into: 0; Since the voltage product term , , Compared with other items, it can be ignored, that is, the fundamental coefficient for: ; Second harmonic coefficient of the inverting input signal The equation is: ; and In contrast, the product term and can be ignored, then simplified to: ; The fundamental coefficient Substituting the second harmonic coefficient get: ; Third harmonic coefficient The equation is: ; but for: ; Will , Substitution The expression of , we get: ; That is, the first input signals are obtained as follows: , , .

[0037] S400: Calculate a second output signal of the amplifier according to the first input signal, and calculate a first input voltage power and a first total harmonic distortion according to the second output signal; The first input voltage power includes the signal fundamental wave power , Second harmonic power and third harmonic power , the first input signal , , Substitute the input signal The first signal expression of , and substitute the result into the first output signal again Get the components of the second output signal: ; ; ; That is, the signal fundamental power in the first input voltage power for: * =( )*(

[0038] ); Second harmonic power in the first input voltage power for: ; The third harmonic power in the first input voltage power for: .

[0039] The first total harmonic distortion THD is: .

[0040] S500: Obtain a second input voltage power and a second total harmonic distortion of a circuit of a nonlinear amplifier, and compare the second input voltage power and the second total harmonic distortion, the first total harmonic distortion and the second total harmonic distortion.

[0041] For example, by directly measuring the circuit of the nonlinear amplifier, the second input voltage power and the second total harmonic distortion are obtained, and the first input voltage power is compared with the second input voltage power, and the first total harmonic distortion is compared with the second total harmonic distortion, thereby obtaining the difference between the linearized amplifier circuit for which negative impedance design is performed on the RF amplifier circuit and the circuit for which negative impedance design is not performed, thereby verifying the effect of negative impedance design on the RF amplifier circuit.

[0042] Combined with Figure 8 As shown, assuming the amplifier open-loop gain is 50 and the closed-loop gain is -4, it can be seen that When the linearized fundamental power A is increased by 9% compared with the nonlinear fundamental power B, the linearized second harmonic power C is increased by 4.18% compared with the nonlinear second harmonic power D, but the linearized third harmonic power F is suppressed by 24% compared with the linearized third harmonic power E, thereby improving the total harmonic distortion of the amplifier.

[0043] In some implementations, obtaining the first signal expression includes: S301: Input voltage to the inverting terminal of the amplifier in the amplifier linearization model, and the first signal expression is an assumed expression of the voltage.

[0044] For example, the voltage signal at the inverting terminal of the amplifier includes the feedback signal from the output terminal, so the input voltage signal includes the DC component, fundamental wave and other harmonics at the output terminal. Therefore, the expression of the input signal can be assumed to be: .

[0045] Combined with Figure 6 and attached Figure 7 As shown, in some implementations, the amplifier linearization design verification method further includes: S600: Obtain a third input voltage power and a third total harmonic distortion of an actual circuit of the linear amplifier, and compare the first input voltage power and the third input voltage power, the first total harmonic distortion and the third total harmonic distortion, the second input voltage power and the third input voltage power, the second total harmonic distortion and the third total harmonic distortion.

[0046] For example, after negative impedance compensation is performed on the amplifier circuit, the actual three-input voltage power and the third total harmonic distortion of the linear amplifier circuit are detected, and the first input voltage power is compared with the third input voltage power, and the first total harmonic distortion is compared with the third total harmonic distortion, which is conducive to verifying the first input power and the first total harmonic distortion calculated by the formula, and then determining the accuracy of the first input power and the first total harmonic distortion calculated by the formula, and inferring the accuracy and applicability of the formula; the second input voltage power table is compared with the third input voltage power, and the second total harmonic distortion is compared with the third total harmonic distortion, to determine the actual difference between the linear amplifier circuit and the nonlinear amplifier circuit during operation.

[0047] In some implementations, the amplifier linearization design verification method further includes: S700: Obtain a second signal expression, calculate a third output signal of the linear amplifier according to the secondary transfer characteristics of the nonlinear amplifier and the second signal expression, obtain fourth node data of the inverting end of the amplifier, and obtain a second input signal of the inverting end of the amplifier according to the fourth node data, the second signal expression, and the third output signal.

[0048] For example, in conjunction with Figure 4 As shown, the equal amplitude dual tone signal at the amplifier input for: ; in, represents the amplitude of the equal-amplitude dual carrier, and Indicates the frequency of the equal-amplitude dual carrier; Since the input signal at the inverting terminal of the amplifier contains the feedback signal from the output terminal, in order to simplify the calculation and focus on evaluating the third-order intermodulation distortion, it is assumed that the input signal is of equal amplitude. The second expression is: ; According to the secondary transmission characteristics of the nonlinear amplifier and the equal-amplitude input signal The second expression can be used to calculate the third output signal for: ; The fourth node data is: ; The equal amplitude dual tone signal , equal amplitude input signal The second expression and the third output signal Substitute the data of the fourth node to obtain the second input signal: the fundamental coefficient of the input signal at the inverting end of the amplifier and the third harmonic coefficient : ; .

[0049] In some implementations, obtaining the second signal expression includes: S701: Input an equal-amplitude dual-tone signal to an inverting terminal of a linear amplifier, wherein the second signal expression is an assumed expression of the equal-amplitude dual-tone signal.

[0050] The intermodulation distortion at the output of the amplifier needs to be obtained through a two-tone test. Therefore, it is assumed that the equal-amplitude two-tone signal at the input of the amplifier for: ; Since the input signal at the inverting terminal of the amplifier contains the feedback signal from the output terminal, in order to simplify the calculation and focus on evaluating the third-order intermodulation distortion, it is assumed that the input signal is of equal amplitude. The second expression is: .

[0051] In some implementations, the amplifier linearization design verification method further includes: S800: Calculate a fourth output signal according to the second input signal, and calculate a first equal-amplitude power and a first intermodulation distortion according to the amplifier output signal.

[0052] The first constant amplitude power includes the constant amplitude fundamental wave power and third-order intermodulation power , the fundamental coefficient of the input signal at the inverting end of the amplifier and the third harmonic coefficient Substitute the equal amplitude input signal The second expression of the equal-amplitude input signal Substitute the second expression into the third output signal Get the fourth output signal: ; Therefore, the fundamental coefficient of the amplifier output signal is , third-order intermodulation coefficient They are: ; ; Therefore, the equal-amplitude fundamental power at the amplifier output can be calculated for: = * ; The fundamental coefficient Substitute the fundamental power of equal amplitude into The fundamental power can be calculated The value of Third-order intermodulation power for: = * ; The third-order intermodulation coefficient Substitute the third-order intermodulation power The third-order intermodulation power can be calculated The value of The first intermodulation distortion IDM3 is: .

[0053] In some implementations, the amplifier linearization design verification method further includes: S900: Obtain a second equal-amplitude power and a second intermodulation distortion of the circuit of the nonlinear amplifier, and compare the first equal-amplitude power and the second equal-amplitude power, the first intermodulation distortion and the second intermodulation distortion.

[0054] For example, by measuring the nonlinear amplifier circuit, the second equal-amplitude power and the second intermodulation distortion of the nonlinear amplifier circuit can be directly obtained. By comparing the first equal-amplitude power and the second equal-amplitude power, and comparing the first intermodulation power and the second intermodulation power, the difference between the linear amplifier circuit for which negative impedance design is performed on the RF amplifier circuit and the circuit for which negative impedance design is not performed can be obtained, thereby verifying the effect of negative impedance design on the RF amplifier circuit.

[0055] Combined with Fig. 9 As shown, Figure 6 for dB, dB, the simulation results of the output power of the amplifier before and after linearization when the closed-loop gain is 4. It can be seen that at 0.1V, the linearized fundamental power G is increased by 9% compared with the nonlinear fundamental power H, and the linearized third-order intermodulation power J is suppressed by 18% compared with the nonlinear third-order intermodulation power I, so the intermodulation distortion and third-order intermodulation power are increased by 25dB and 18dBm respectively.

[0056] Combined with Figure 6 and attached Figure 7 As shown, in some implementations, the amplifier linearization design verification method further includes: S110: Obtain a third equal-amplitude power and a third intermodulation distortion of an actual circuit of the linear amplifier, and compare the first equal-amplitude power and the third equal-amplitude power, the first intermodulation distortion and the third intermodulation distortion, the second equal-amplitude power and the third equal-amplitude power, the second intermodulation distortion and the third intermodulation distortion.

[0057] For example, after negative impedance compensation is performed on the amplifier circuit, the actual three equal-amplitude powers and the third intermodulation distortion of the linearized amplifier circuit are detected, and the first equal-amplitude power is compared with the third equal-amplitude power, and the first intermodulation distortion is compared with the third intermodulation distortion, which is conducive to verifying the first input power and the first intermodulation distortion calculated by the formula, and then determining the accuracy of the first input power and the first intermodulation distortion calculated by the formula, and inferring the accuracy and applicability of the formula; the second equal-amplitude power table is compared with the third equal-amplitude power table, and the second intermodulation distortion is compared with the third intermodulation distortion, to determine the actual difference between the linearized amplifier circuit and the nonlinear amplifier circuit during operation.

[0058] Combined with Figure 5 As shown, the peripheral circuits of the auxiliary amplifier and the RF amplifier adopt similar designs, where: , , The auxiliary amplifier below is used to generate compensation impedance, which is used to reduce the input impedance of the RF amplifier. Set to negative impedance: .

[0059] Combined with Figure 6 As shown, the differential amplifier consists of , , , , , , , Bias, to simplify the circuit design, all transistors are of the same type. If the amplifier closed-loop gain is -4, then and The values ​​of can be selected as 2kΩ and 500Ω respectively, then The values ​​are: ; Combined with Figure 7 As shown, the differential amplifier is designed using the HFA3127 transistor array chip. Since the entire circuit requires six transistors and four diodes, two HFA3127 chips are used. The extra transistors in the transistor array are used as diodes by shorting the base-collector junctions.

[0060] Combined with Fig.10 As shown, the frequency response of the experimental circuit is measured using a network analyzer. It can be seen that after adopting the linearization method proposed in the present invention, the gain of the amplifier is increased by more than 1 times.

[0061] Combined with Fig.11As shown, two equal-amplitude signals are input near 150MHz for dual-tone testing. According to the analysis, after the linearization method proposed in the present invention is adopted, the amplifier gain and IMD3 are increased by 10.5% and 8 dB respectively; for the amplifier without linearization and linearization, the calculated output IMD3 is -9.5 dBm and -3.5 dBm respectively. The above analysis shows that the linearization method proposed in the present invention improves the linearity of the amplifier.

[0062] In some embodiments, the first input voltage power includes: signal fundamental power, second harmonic power and third harmonic power; the first equal-amplitude power includes: equal-amplitude fundamental power and third-order intermodulation power, and a comparison is performed on the signal fundamental power, the second harmonic power and the third harmonic power to confirm the difference between the nonlinear amplifier circuit, the linear amplifier circuit model and the actual circuit of the linear amplifier, thereby completing the verification of the linear design of the amplifier, and confirming the reliability and accuracy of the verification result; a comparison is performed on the equal-amplitude fundamental power and the third-order intermodulation power to confirm the difference between the nonlinear amplifier circuit, the linear amplifier circuit model and the actual circuit of the linear amplifier, thereby completing the verification of the linear design of the amplifier, and confirming the reliability and accuracy of the verification result.

[0063] A storage medium stores a computer program, which is used to implement the above method when executed.

[0064] In summary, the present invention provides an amplifier linearization design verification method and a storage medium, which compensates the nonlinear amplifier circuit by utilizing negative impedance compensation, thereby improving the closed-loop gain and linearity of the nonlinear amplifier circuit, thereby reducing the nonlinear distortion of the amplifier. At the same time, fewer devices are required, thereby improving the overall reliability of the circuit; by analyzing the total harmonic distortion and intermodulation distortion of the linearized amplifier circuit, the relative distortion level of each harmonic component of the linearized amplifier circuit can be clearly expressed, and the complexity of the entire amplifier circuit is reduced, and the flexibility of building the amplifier circuit is improved, thereby improving the applicability of the amplifier linearization design verification method.

[0065] The above implementation modes are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with this technology to understand the content of the present invention and implement it. They cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for verifying amplifier linearization design, characterized in that: include: Acquire first node data of an inverting input terminal of an ideal amplifier in a feedback amplifier circuit and second node data of an inverting output terminal of a non-ideal amplifier, and calculate an error term according to the first node data and the second node data; Calculate negative impedance compensation according to the error term, and establish a linearized amplifier model according to the negative impedance compensation and the feedback amplifier circuit; Obtain a first signal expression, calculate a first output signal of the linear amplifier according to the secondary transfer characteristic of the nonlinear amplifier and the first signal expression, obtain third node data of the inverting end of the amplifier, and obtain a first input signal of the inverting end of the amplifier according to the third node data, the first signal expression, and the first output signal; Calculate a second output signal of the amplifier according to the first input signal, and calculate a first input voltage power and a first total harmonic distortion according to the second output signal; A second input voltage power and a second total harmonic distortion of the circuit of the nonlinear amplifier are obtained, and the second input voltage power and the second total harmonic distortion, the first total harmonic distortion and the second total harmonic distortion are compared.

2. The amplifier linearization design verification method according to claim 1, characterized in that: The obtaining of the first signal expression comprises: inputting a voltage into the inverting terminal of the amplifier in the amplifier linearization model, and the first signal expression is an assumed expression of the voltage.

3. The amplifier linearization design verification method according to claim 1, characterized in that: The method also includes: obtaining a third input voltage power and a third total harmonic distortion of an actual circuit of the linear amplifier, and comparing the first input voltage power and the third input voltage power, the first total harmonic distortion and the third total harmonic distortion, the second input voltage power and the third input voltage power, the second total harmonic distortion and the third total harmonic distortion.

4. The amplifier linearization design verification method according to claim 1, characterized in that: The method also includes: obtaining a second signal expression, calculating a third output signal of the linear amplifier according to the secondary transfer characteristics of the nonlinear amplifier and the second signal expression, obtaining fourth node data of the inverting end of the amplifier, and obtaining a second input signal of the inverting end of the amplifier according to the fourth node data, the second signal expression, and the third output signal.

5. The amplifier linearization design verification method according to claim 3, characterized in that: The obtaining of the second signal expression comprises: inputting an equal-amplitude dual-tone signal into the inverting terminal of the linear amplifier, and the second signal expression is an assumed expression of the equal-amplitude dual-tone signal.

6. The amplifier linearization design verification method according to claim 3, characterized in that: A fourth output signal is calculated according to the second input signal, and a first equal-amplitude power and a first intermodulation distortion are calculated according to the amplifier output signal.

7. The amplifier linearization design verification method according to claim 6, characterized in that: The method further includes: obtaining a second equal-amplitude power and a second intermodulation distortion of the circuit of the nonlinear amplifier, and comparing the first equal-amplitude power with the second equal-amplitude power, the first intermodulation distortion and the second intermodulation distortion.

8. The amplifier linearization design verification method according to claim 7, characterized in that: The method also includes: obtaining a third equal-amplitude power and a third intermodulation distortion of an actual circuit of the linear amplifier, and comparing the first equal-amplitude power and the third equal-amplitude power, the first intermodulation distortion and the third intermodulation distortion, the second equal-amplitude power and the third equal-amplitude power, the second intermodulation distortion and the third intermodulation distortion.

9. The amplifier linearization design verification method according to claim 6, characterized in that: The first input voltage power includes: signal fundamental wave power, second harmonic power and third harmonic power; the first constant amplitude power includes: constant amplitude fundamental wave power and third-order intermodulation power.

10. A storage medium, characterized in that: The storage medium stores a computer program, which is used to implement the method according to any one of claims 1 to 9 when executed.

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