A power amplifier index test device and test method

Abstract

The application discloses a kind of power amplifier index test device and test method, belong to test technical field.The application is obtained by input interval adaptive test method to test safe measurement input interval, avoid the security risk caused by input power in the test process due to the lack of understanding of the performance of power amplifier by test personnel;The application is compensated by the loss and frequency response of microwave line and component, which makes up for the defects of neglecting microwave line loss, frequency response calculation of microwave connection component in existing automatic test and manual test, overcomes the influence of loss compensation and component frequency response, and improves the accuracy of test index;The application improves test efficiency by improving power amplifier test algorithm method, solves the problem of test speed and accuracy in existing automatic test method and manual test process.

Description

Technical Field

[0001] This invention belongs to the field of testing technology, specifically relating to a power amplifier performance testing device and testing method. Background Technology

[0002] Power amplifiers are essential testing instruments in high-power testing systems, electromagnetic compatibility testing, and other fields. Currently, with the continuous development of microwave testing technology, the performance indicators of power amplifiers are particularly important. The following problems in current testing techniques urgently need to be addressed:

[0003] Manual testing is inefficient and has limited accuracy. Setting instrument readings and recording test results manually is time-consuming and prone to errors, resulting in low accuracy of test indicators.

[0004] Microwave line loss compensation calculations are complex and tedious. During microwave instrument measurements, connection losses in the lines and cables, as well as the frequency response of different microwave connecting components (such as attenuators), can significantly affect measurement accuracy. Microwave line losses are easily overlooked in general automated and manual testing, and the frequency response testing of microwave connecting components is complex, leading to tedious compensation calculations.

[0005] There are safety hazards in testing the input power range. Because the performance of the power amplifier is unknown, the test input power range is usually set by the tester based on their own experience before testing. Therefore, there is uncertainty in the input test power and instability in the input power during the test, which can easily cause machine damage and low test efficiency.

[0006] The performance of the test index algorithm is low. The test algorithm is designed based on the power amplifier principle. The methods for testing various indicators of power amplifiers are different. Moreover, most existing test methods adopt the point-by-point reading method, which lacks flexibility and cannot balance the speed and accuracy of the test.

[0007] Power amplifier testing principle

[0008] Gain (G): Characterizes the amplification capability of a power amplifier for a signal. It refers to the logarithmic ratio of the output power to the input power when the input and output ports are well matched. The unit is dB. The expression is as follows:

[0009] G(dB)=P out (dBm)-P in (dBm)

[0010] Gain flatness (ΔG): refers to the range of fluctuation in the output power amplitude of a power amplifier as a function of frequency, under the same input power. Its expression is as follows:

[0011]

[0012] G max G is the maximum gain within the operating frequency range. min This represents the minimum gain at the operating frequency.

[0013] P1dB, P3dB, Psat points: such as Figure 1 When a power amplifier is operating, in the linear region, as the input power increases, the output power increases linearly (with a slope of 1), such as... Figure 1 Ideal output power line. In the nonlinear region, the output power is as follows: Figure 1 The actual output power curve is shown in the figure. At this point, if the input power increases by 1dB, the output power increment is less than 1dB. The difference between the actual output power and the ideal output power is 1dB, which is defined as the P1dB point; the difference between the actual output power and the ideal output power is 3dB, which is defined as the P3dB point; and the actual output power remains constant at saturation output, which is defined as the Psat point.

[0014] Harmonic suppression: Due to the nonlinear effect of the amplifier, a series of harmonics will be generated at the amplifier output during operation. Harmonic suppression (HD) is the logarithm of the ratio of harmonic power to fundamental power, expressed as follows:

[0015]

[0016] HD n P represents the suppression of the nth harmonic. n P represents the power of the nth harmonic. s This indicates the fundamental frequency power.

[0017] Existing technical solutions:

[0018] Manual testing requires multiple testers to operate the equipment, manually adjust buttons, read instrument panel readings, and manually calculate and record the results, making the process cumbersome. Furthermore, due to the long testing time, the power amplifier's performance may vary under different temperature conditions. Additionally, factors such as cable loss and the frequency response of microwave connectors in the test circuit further complicate manual testing.

[0019] Automated Testing: Many existing automated testing methods for power amplifier specifications employ similar connection methods, involving a host computer connecting to the instrument and using programmed commands to read the instrument's test information. The input power range is manually set, and data is collected by scanning and matching conditions point by point according to the set power steps, ultimately calculating the results.

[0020] However, the test method does not take into account factors such as cable loss and frequency response of microwave connectors, which can easily lead to errors in the test results; manually setting the test input power range and step size can easily cause machine damage and low test efficiency; and using a point-by-point traversal method to collect test data lacks flexibility and cannot balance test speed and accuracy.

[0021] The existing automatic testing technology for power amplifiers has the following drawbacks:

[0022] 1. Poor testing safety: In existing automatic testing technology for power amplifiers, the test input power range is determined based on the tester's own testing experience. During the testing process, due to the tester's lack of understanding of the power amplifier's performance, inaccurate test range settings and instability in the test input power can easily occur, leading to safety hazards during the testing process.

[0023] 2. Low testing accuracy: During microwave instrument measurements, connection losses in the circuit cables and the frequency response of different microwave connecting components can significantly affect the accuracy of the measurements. Existing automatic and manual testing methods often overlook microwave circuit losses, and the frequency response testing of microwave connecting components is complex, making loss compensation and component frequency response extremely important for the accuracy of test results.

[0024] 3. Low testing efficiency: Existing automatic testing technologies for power amplifiers mostly adopt a test method that incrementally increases the input power readings for power amplifier performance testing. This method lacks flexibility and cannot balance the speed and accuracy of the test. Summary of the Invention

[0025] In view of the above-mentioned technical problems existing in the prior art, the present invention proposes a power amplifier performance testing device and testing method, which is reasonably designed, overcomes the shortcomings of the prior art, and has good results.

[0026] To achieve the above objectives, the present invention adopts the following technical solution:

[0027] A power amplifier performance testing device includes a signal source, a power meter, a spectrum analyzer, an instrument under test (DUT), a microwave component under test (DUT), and a host computer.

[0028] The host computer is connected to the signal source, power meter, spectrum analyzer, and instrument under test via cable through a general communication connection port GPIB, LAN, or USB.

[0029] The instrument under test and the microwave component under test are connected to the signal source, power meter, and spectrum analyzer respectively via microwave cables;

[0030] The signal source is configured to send test signals;

[0031] A power meter is configured to receive a test signal and display the power value of the test signal.

[0032] A spectrum analyzer is configured to reflect the spectral characteristics of a received test signal;

[0033] The host computer is configured to read information in real time, complete the test, and generate test results.

[0034] Preferably, the microwave component under test includes an attenuator and an adapter;

[0035] An attenuator is configured to attenuate the power of the test signal;

[0036] An adapter is configured to enable the transmission and distribution of signals.

[0037] Furthermore, this invention also mentions a method for testing the performance of a power amplifier, which employs a power amplifier performance testing device as described above; the method includes the following steps:

[0038] Step 1: Microwave circuit compensation test;

[0039] Step 2: Input interval adaptive test;

[0040] Step 3: Performance testing of the power amplifier;

[0041] Step 4: Output the test results.

[0042] Preferably, step 1 specifically includes the following steps:

[0043] Step 1.1: Cable loss measurement;

[0044] Set the test frequency range and power range for cable loss. The frequency range is the operating frequency range of the instrument under test, and the power range is the estimated minimum input power and maximum output power of the instrument under test. The cable loss is calculated by controlling the output test signal of the signal source and reading the test signal power of the power meter, and then recorded to the host computer.

[0045] When the signal source output power is P signal The power meter reading is P. power In ideal circumstances, P signal =P power In reality, cable connections suffer from losses (P). loss P loss =P signal -P power ;

[0046] Step 1.2: Frequency response measurement of the microwave component under test;

[0047] Place the microwave component under test at the test location. Based on the measured cable loss, set the test frequency range and power range. Control the signal source to output the test signal and the power meter to read the test signal power. Calculate the frequency response of the microwave component under test and record it to the host computer.

[0048] After loading the microwave component under test, when the output power of the signal source is P signal The power meter reading is P. power At this time, the frequency response of the microwave component under test is P. freq P freq =P signal -P power -P loss ;

[0049] Step 1.3: Ensure measurement accuracy by interpolating loss and frequency response for different frequency and power ranges.

[0050] Preferably, in step 2, the purpose of the input range adaptive test is to determine the safe input power range of the power amplifier under the condition that the performance of the power amplifier under test is unknown. According to the amplification characteristics of the power amplifier, when the power amplifier is working, its operating region is divided into a linear region and a nonlinear region as the input power increases. The nonlinear region includes a saturation region and an unsaturation region. The specific test process is as follows:

[0051] During operation, the output power of a power amplifier fluctuates within a certain range due to temperature factors. Therefore, a threshold value is set to determine the fluctuation range.

[0052] Control the signal source and set the signal power at the input of the power amplifier in the linear region to P. start The input power signal is incremented in specific steps to read the output power value. When the input power increases, it increases from Pin1 to Pin2 in specific steps. Ideally, the output power in the linear region should be Pout2. If the output power is Pout3 or Pout4 at this time, the output power in the interval... If the output power is within the linear region, then the current power amplifier is determined to be in the linear region; if the output power is Pout5, Then it is determined that the power amplifier has entered the nonlinear region;

[0053] After the power amplifier enters the nonlinear region, the input power signal is input in specific steps P1, P2, P3, P4, P5, and P6, corresponding to an output power of P. a P b P c P d P e P f ;

[0054] when and At that time, determine P b At this point, the power amplifier operates in the nonlinear region;

[0055] when and When, determine P c At this point, the power amplifier begins to enter the saturation region.

[0056] when and When, determine the output power P d At this point, the power amplifier is operating in the saturation region;

[0057] when and When determining the output power P e The point is in the saturation region;

[0058] After entering the saturation region, the output power meets the requirements. At the same time, and Then determine P e Point P is the saturated power output point. sat The corresponding input frequency is P6, and the interval cutoff input power is P. end Test the safe range of input power [P] start P end ].

[0059] Preferably, in step 3, the power amplifier performance indicators include gain G, gain flatness ΔG, and P1dB, P3dB, and Psat points;

[0060] Gain G: Characterizes the amplification capability of a power amplifier for a signal. It refers to the logarithmic ratio of output power to input power when the input and output ports are well matched. The unit is dB. The expression is as follows:

[0061] G(dB)=P out (dBm)-P in (dBm);

[0062] Gain flatness ΔG: refers to the range of fluctuation in the output power amplitude of a power amplifier as frequency changes under the same input power; its expression is as follows:

[0063]

[0064] Among them, G max G is the maximum gain within the operating frequency range. min This represents the minimum gain at the operating frequency.

[0065] P1dB, P3dB, and Psat points: The power amplifier operates in a linear region. Within this linear region, the output power increases linearly with the increase of input power.

[0066] After the power amplifier enters the nonlinear region, the output power is the actual output power curve. At this time, if the input power increases by 1dB, the output power increment is less than 1dB. When the difference between the actual output power and the ideal output power is 1dB, it is defined as the P1dB point.

[0067] When the difference between the actual output power and the ideal output power is 3dB, it is defined as the P3dB point.

[0068] The point Psat is defined as the point where the actual output power remains constant at saturation output.

[0069] Harmonic suppression (HD): Due to the nonlinear effect of the power amplifier, a series of harmonics will be generated at the output during operation. Harmonic suppression is the logarithm of the ratio of harmonic power to fundamental power, expressed as follows:

[0070]

[0071] Among them, HD n P represents the suppression of the nth harmonic. n P represents the power of the nth harmonic. s This indicates the fundamental frequency power.

[0072] Preferably, the calculation methods for gain and gain flatness are as follows:

[0073] Step S01: Obtain the test safety interval [P] based on the input interval adaptive test. start P end ];

[0074] Step S02: Linear region, obtain the input power and output power at the corresponding point, and calculate the gain at the corresponding point;

[0075] Step S03: Calculate the average gain of the selected linear region points to obtain the gain at each frequency;

[0076] Step S04: Sort the gain values ​​at different frequencies, according to Calculate the gain flatness.

[0077] Preferably, the calculation methods for P1dB, P3dB, and Psat points are as follows:

[0078] Step S11: Determine the test safety interval based on the input interval adaptive test [P] start P end Determine the Psat point;

[0079] Step S12: Set the judgment threshold as Δ and the value accuracy. Based on the obtained safe range of input power, design the interval bisection method. By narrowing the value range, continuously adjust the test input power Pin. When the actual output power Pr and the ideal output power Pd pass the judgment condition and reach the value accuracy, the point that meets the condition is judged as the P1dB point. Similarly, obtain the P3dB point.

[0080] Preferably, the calculation methods for second harmonic suppression and third harmonic suppression are as follows:

[0081] Step S31: Select the measurement path of the spectrum analyzer, load the measured P1dB, P3dB, and Psat data, and automatically set the spectrum analyzer bandwidth to 100M;

[0082] Step S32: Start the test, set the frequency to be tested, and set the input power points P1dB, P3dB, and Psat at the corresponding frequency as the input power of the test signal;

[0083] Step S33: Set and mark the instrument center frequency points for the fundamental, second harmonic, and third harmonic respectively, and read the corresponding values ​​for calculation;

[0084] Step S34: Calculate the difference and record the second and third harmonic suppression values ​​at each test point.

[0085] The beneficial technical effects of this invention are as follows:

[0086] 1. The safety of testing is further improved. This invention application obtains a safe measurement input range by using an input range adaptive testing method, which avoids safety hazards caused by input power during the test due to the tester's lack of understanding of the power amplifier performance;

[0087] 2. The accuracy of testing is further improved. This invention application compensates for the shortcomings of microwave circuit loss and frequency response calculation in existing automatic and manual testing by using a method of microwave circuit and component loss and frequency response compensation. It overcomes the influence of loss compensation and component frequency response, and improves the accuracy of test indicators.

[0088] 3. Further improvement in testing efficiency: This invention improves the power amplifier testing algorithm by using a binary search method to determine matching, thereby further improving search efficiency and achieving a measurement accuracy of 0.01. This overcomes the speed and accuracy problems of existing automatic testing methods and manual testing processes, thus further improving testing efficiency. Attached Figure Description

[0089] Figure 1 This is a schematic diagram of the power amplifier's operating curve;

[0090] Figure 2 This is a flowchart of the testing method of the present invention;

[0091] Figure 3 This is a schematic diagram of the testing device of the present invention;

[0092] Figure 4 This is a schematic diagram of the operating region of the power amplifier;

[0093] Figure 5 A schematic diagram of the curve for determining the linear region;

[0094] Figure 6 A schematic diagram of the change curve in the nonlinear region;

[0095] Figure 7 A schematic diagram for determining the adaptive test interval;

[0096] Figure 8 The flowchart shows the algorithm for testing the P1dB point. Detailed Implementation

[0097] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0098] This invention proposes a test method for power amplifier performance with adaptive test range and automatic loss compensation.

[0099] Power amplifier test parameters: gain, gain flatness, P 1dB P 3dB P sat Second harmonic, third harmonic.

[0100] The testing instruments used include: signal generator, power meter, spectrum analyzer, and power amplifier under test.

[0101] Test method: The test is conducted automatically via software. The host computer and the test instruments are connected by cable through communication ports GPIB, LAN or USB. The host computer software is developed in C++Qt and can monitor and query the status information of each test instrument in real time.

[0102] Test results: Output specific text formats (CSV, EXCEL, TXT, etc.), and plot characteristic curves according to requirements to intuitively reflect the test results.

[0103] The test steps consist of four parts: microwave circuit compensation test, input range adaptive test, power amplifier performance index test, and test result output. The following steps are in order to... Figure 2 The first three steps are explained in the middle section.

[0104] 1. Microwave circuit compensation test

[0105] For microwave circuit compensation testing, after the test environment is set up and connected, the cable loss is first measured by direct cable connection. Then, the microwave components under test (adapters, attenuators, etc.) are tested, and the component loss and frequency response are measured and recorded in the host computer automatic test software.

[0106] Test principle:

[0107] Cable loss measurement: The instrument is directly connected to the cable for measurement. When the signal source output power is P... signal The power meter reading is P. power In ideal circumstances, P signal =P power In reality, cable connections suffer from losses (P). loss P loss =P signal -P power ;

[0108] Component frequency response measurement: based on the measured cable loss P loss The measurement was performed using an instrument test circuit. After loading and testing the microwave components, the signal source output power was P. signal The power meter reading is P. power At this time, the frequency response of the component is P. freq P freq =P signal -P power -P loss ;

[0109] Measurement method:

[0110] (1) Adopt Figure 3 The test uses a direct cable connection (Method 1) and sets the test frequency and power range (the frequency range is the operating frequency range of the instrument under test, and the power range is the estimated minimum input power and maximum output power of the instrument under test). The cable loss is calculated and recorded on the host computer by controlling the signal source output and reading the power meter.

[0111] (2) Adopt Figure 3 The test circuit uses connection method 2. The microwave component under test (attenuator, adapter, etc.) is placed at the measurement position. Based on the measured cable loss, calculations are performed to set the test frequency range and power range (the frequency range is the operating frequency range of the instrument under test, and the power range is the estimated minimum input power and maximum output power of the instrument under test). The frequency response of the microwave component is calculated and recorded on the host computer by controlling the output of the control signal source and the input of the power meter.

[0112] (3) Ensure measurement accuracy. For the test frequency range and power range, perform loss and frequency response interpolation, as shown in Table 1 below.

[0113] Table 1. Power loss and frequency response at different frequencies

[0114] Frequency 1 <![CDATA[P loss11 ,P freq11 ]]> <![CDATA[P loss12 ,P freq12 ]]> …,… Frequency 2 <![CDATA[P loss21 ,P freq21 ]]> <![CDATA[P loss22 ,P freq22 ]]> …,… … …,… …,… …,…

[0115] 2. Input Range Adaptive Testing

[0116] Test principle:

[0117] The purpose of input range adaptive testing is to determine the safe input power range under conditions where the performance of the power amplifier under test is unknown. Based on the amplification characteristics of a power amplifier, its operating region is divided into linear and nonlinear regions as the input power increases. The nonlinear region includes saturation and unsaturation regions.

[0118] like Figure 4 As shown, the amplifier operates in the linear region, with an input power P. in With output power P out There is a linear relationship, P out =P in ×k, k=1, input power P in When the input increases by a1, the output power P out The corresponding output increases by a2, at which point a1 = a2;

[0119] The amplifier operates in the nonlinear region, with input power P in With output power P out There is a nonlinear relationship, the input power P in When the input increases by a1, the output power P out The corresponding output increases by a2, at which point a1 > a2;

[0120] The amplifier operates in the saturation region, with input power P. in As input increases, output power P out It remains stable and tends towards saturation.

[0121] Taking advantage of this characteristic, the input small-signal power P operating in the linear region start By continuously increasing the input power, the characteristics of each region are used to determine whether the input power has increased to the saturation region. Once the saturation region is reached, the saturation power output point P is obtained. sat The corresponding input power P at this time end Then the safe range of the test input power [P] is obtained. start P end ].

[0122] Test method:

[0123] During operation, the amplifier's output power will vary within a certain range due to factors such as temperature. Therefore, a threshold value is set to determine the floating range.

[0124] (1) Control the signal source and set the small signal power P of the power amplifier input in the linear region. start The input power signal is incremented in specific steps to read the output power value. For example... Figure 5 As shown, when the input power increases in a specific step size from Pin1 to Pin2, ideally, the output power in the linear region should be Pout2. If the output power is Pout3 or Pout4 at this time, the output power in the interval... If the output power is within the linear region, it can be determined that the amplifier is currently in the linear region; if the output power is Pout5, This indicates that the amplifier has entered the nonlinear region.

[0125] (2) After the amplifier enters the nonlinear region, such as Figure 6 As shown, the input power signal is input in specific steps P1, P2, P3, P4, P5, and P6, and the corresponding output power is P. a P b P c P d P e P f ,when and At that time, P can be determined b At this point, the amplifier operates in the nonlinear region; when and When, determine P c At this point, the amplifier begins to enter the saturation region; when and When this happens, the output power P can be determined. d At this point, the amplifier is operating in the saturation region. and When determining the output power P e The point is in the saturation region.

[0126] After entering the saturation region, the output power meets the requirements. At the same time, and Then determine P e Point P is the saturated power output point. sat The corresponding input frequency is P6, and the interval cutoff input power is P. end Test the safe range of input power [P] start P end ].

[0127] III. Power Amplifier Performance Testing

[0128] 1. Test Metrics Principles:

[0129] Gain (G): Characterizes the amplification capability of a power amplifier for a signal. It refers to the logarithmic ratio of the output power to the input power when the input and output ports are well matched. The unit is dB. The expression is as follows:

[0130] G(dB)=P out (dBm)-P in (dBm)

[0131] Gain flatness (ΔG): refers to the range of fluctuation in the output power amplitude of a power amplifier as a function of frequency, under the same input power. Its expression is as follows:

[0132]

[0133] G max G is the maximum gain within the operating frequency range. min This represents the minimum gain at the operating frequency.

[0134] P1dB, P3dB, Psat points: such as Figure 7 As shown, power amplifiers operate within a linear region. Within this region, as the input power increases, the output power increases linearly, as shown by the ideal output power line in the figure. However, once the amplifier enters the nonlinear region, the output power curve reflects the actual output power. At this point, a 1dB increase in input power results in a less than 1dB increase in output power. The point where the difference between the actual and ideal output power is 1dB is defined as P1dB; the point where the difference is 3dB is defined as P3dB; and the point where the actual output power remains constant at saturation output is defined as Psat.

[0135] Harmonic suppression (HD): Due to the nonlinear effect of the amplifier, a series of harmonics will be generated at the amplifier output during operation. Harmonic suppression is the logarithm of the ratio of harmonic power to fundamental power, expressed as follows:

[0136]

[0137] HD n P represents the suppression of the nth harmonic. n P represents the power of the nth harmonic. s This indicates the fundamental frequency power.

[0138] 2. Algorithm testing:

[0139] Gain, Gain Flatness:

[0140] (1) Obtaining the test safety interval [P] based on adaptive testing of the input interval. start P end ].

[0141] (2) In the linear region, obtain the input power and output power at the corresponding point and calculate the gain at the corresponding point.

[0142] (3) Calculate the average gain of the selected linear points to obtain the gain at each frequency.

[0143] (4) Sort the gain values ​​at different frequencies, according to Calculate the gain flatness.

[0144] Calculation of P1dB, P3dB, and Psat points:

[0145] (1) Determining the test safety interval based on adaptive testing of the input interval [P] start P end ], determine the Psat point.

[0146] (2) Figure 8 The algorithm for testing the P1dB point is described, setting a judgment threshold of Δ and a value accuracy. Based on the obtained safe input power range, a bisection method is designed. By narrowing the value range, the test input power Pin is continuously adjusted. When the actual output power Pr and the ideal output power Pd meet the judgment conditions and the value accuracy is reached, the point that meets the conditions is determined to be the P1dB point. Similarly, the P3dB point is obtained.

[0147] Second harmonic suppression and third harmonic suppression calculations:

[0148] (1) Select the spectrum analyzer measurement path, load the measured P1dB, P3dB and Psat data, and automatically set the spectrum analyzer bandwidth to 100M.

[0149] (2) Start the test, set the frequency to be tested, and set the input power P1dB, P3dB and Psat points at the corresponding frequencies as the input power of the test signal; (3) Set the instrument center frequency points and mark them for the fundamental, second harmonic and third harmonic respectively, and read the corresponding values ​​for calculation.

[0150] (4) By calculating the difference, record the second harmonic suppression and third harmonic suppression values ​​at each test point. The key points of this invention application are as follows:

[0151] The first key technical point is the automatic compensation for losses and frequency response of microwave circuits and components. Before testing the power amplifier specifications, cable losses and the frequency response of microwave connecting components are measured and recorded at different frequency points and power points using different measurement methods between microwave instruments. This allows the effects of losses and frequency response to be ignored during the power amplifier testing process, improving the accuracy of the test results.

[0152] The second key technical point is the input range adaptive testing method. To improve the safety and stability during the testing of power amplifiers, a safe test input power range is determined based on the power amplifier's operating characteristic curve, which greatly ensures test safety.

[0153] The third key technical point is the improvement of the power amplifier testing algorithm. Compared with the existing mainstream testing methods, which match point by point according to the input power point, the algorithm uses a binary search method to judge the matching, which improves the search efficiency and the measurement accuracy can be accurate to 0.01. The speed and efficiency of the test are significantly improved.

[0154] Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A method for testing the performance indicators of a power amplifier, characterized in that: A power amplifier performance testing device is used, which includes a signal source, a power meter, a spectrum analyzer, an instrument under test, a microwave component under test, and a host computer; The host computer is connected to the signal source, power meter, spectrum analyzer, and instrument under test via cable through a general communication connection port GPIB, LAN, or USB. The instrument under test and the microwave component under test are connected to the signal source, power meter, and spectrum analyzer respectively via microwave cables; The signal source is configured to send test signals; A power meter is configured to receive a test signal and display the power value of the test signal. A spectrum analyzer is configured to reflect the spectral characteristics of a received test signal; The host computer is configured to read information in real time, complete the test, and generate test results; this includes the following steps: Step 1: Microwave circuit compensation test; specifically including the following steps: Step 1.1: Cable loss measurement; Set the test frequency range and power range for cable loss. The frequency range is the operating frequency range of the instrument under test, and the power range is the estimated minimum input power and maximum output power of the instrument under test. The cable loss is calculated by controlling the output test signal of the signal source and reading the test signal power of the power meter, and then recorded to the host computer. When the signal source output power is The power meter reading is In ideal circumstances, In reality, cable connections suffer from losses. , ; Step 1.2: Frequency response measurement of the microwave component under test; Place the microwave component under test at the test location. Based on the measured cable loss, set the test frequency range and power range. Control the signal source to output the test signal and the power meter to read the test signal power. Calculate the frequency response of the microwave component under test and record it to the host computer. After loading the microwave component under test, when the output power of the signal source is The power meter reading is At this time, the frequency response of the microwave component under test is , ; Step 1.3: Ensure measurement accuracy by interpolating loss and frequency response for different frequency and power ranges; Step 2: Input interval adaptive test; The purpose of the input range adaptive test is to determine the safe input power range of the power amplifier under the condition that the performance of the power amplifier under test is unknown. According to the amplification characteristics of the power amplifier, when the power amplifier is working, its working region is divided into linear region and nonlinear region as the input power increases. The nonlinear region includes saturation region and non-saturation region. Step 3: Performance testing of the power amplifier; The performance metrics of a power amplifier include gain G and gain flatness. And P1dB, P3dB, and Psat points; Step 4: Output the test results.

2. The power amplifier performance testing method according to claim 1, characterized in that: The microwave components under test include attenuators and adapters; An attenuator is configured to attenuate the power of the test signal; An adapter is configured to enable the transmission and distribution of signals.

3. The power amplifier performance testing method according to claim 1, characterized in that: The specific testing process for step 2 is as follows: Due to temperature fluctuations during operation, the output power of a power amplifier fluctuates within a certain range. Therefore, a threshold value is set to determine the fluctuation range. ; Control the signal source and set the signal power at the power amplifier input in the linear region to be [value missing]. The input power signal is incremented in specific steps to read the output power value. When the input power increases, it increases from Pin1 to Pin2 in specific steps. Ideally, the output power in the linear region should be Pout2. If the output power is Pout3 or Pout4 at this time, the output power in the interval... If the output power is within the linear region, then the current power amplifier is determined to be in the linear region; if the output power is Pout5, If so, it is determined that the power amplifier has entered the nonlinear region; After the power amplifier enters the nonlinear region, the input power signal is stepped in a specific manner. , , , , , Input, corresponding output power is , , , , , ; when and At that time, determine At this point, the power amplifier operates in the nonlinear region; when and At that time, make a judgment At this point, the power amplifier begins to enter the saturation region. when and At that time, determine the output power. At this point, the power amplifier is operating in the saturation region; when and At that time, determine the output power The point is in the saturation region; After entering the saturation region, the output power meets the requirements. At the same time, and Then determine Point is the saturation power output point Its corresponding input frequency is For the interval cutoff input power Test the safe range of input power .

4. The power amplifier performance testing method according to claim 1, characterized in that: In step 3, Gain G: Characterizes the amplification capability of a power amplifier for a signal. It refers to the logarithmic ratio of output power to input power when the input and output ports are well matched. The unit is dB. The expression is as follows: ； Gain flatness This refers to the range within which the output power amplitude of a power amplifier fluctuates with frequency under the same input power conditions. Its expression is as follows: ； in, This represents the maximum gain within the operating frequency range. This represents the minimum gain at the operating frequency. P1dB, P3dB, and Psat points: The power amplifier operates in a linear region. Within this region, as the input power increases, the output power increases linearly accordingly. After the power amplifier enters the nonlinear region, the output power is the actual output power curve. At this time, if the input power increases by 1dB, the output power increment is less than 1dB. When the difference between the actual output power and the ideal output power is 1dB, it is defined as the P1dB point. When the difference between the actual output power and the ideal output power is 3dB, it is defined as the P3dB point. The point Psat is defined as the point where the actual output power remains constant at saturation output. Harmonic suppression (HD): Due to the nonlinear effect of the power amplifier, a series of harmonics will be generated at the output during operation. Harmonic suppression is the logarithm of the ratio of harmonic power to fundamental power, expressed as follows: in, This indicates the suppression of the nth harmonic. This represents the power of the nth harmonic. This indicates the fundamental frequency power.

5. The power amplifier performance testing method according to claim 4, characterized in that: The calculation methods for gain and gain flatness are as follows: Step S01: Obtain the test safety interval based on the input interval adaptive test ; Step S02: Linear region, obtain the input power and output power at the corresponding point, and calculate the gain at the corresponding point; Step S03: Calculate the average gain of the selected linear region points to obtain the gain at each frequency; Step S04: Sort the gain values ​​at different frequencies, according to Calculate the gain flatness.

6. The power amplifier performance testing method according to claim 4, characterized in that: The calculation methods for P1dB, P3dB, and Psat points are as follows: Step S11: Determine the test safety interval based on the input interval adaptive test Determine the Psat point; Step S12: Set the judgment threshold as follows Regarding the accuracy of the value, based on the obtained safe range of input power, a range bisection method is designed. By narrowing the value range, the test input power Pin is continuously adjusted. When the actual output power Pr and the ideal output power Pd meet the judgment conditions and the value accuracy is reached, the point that meets the conditions is determined to be the P1dB point. Similarly, the P3dB point is obtained.

7. The power amplifier performance testing method according to claim 4, characterized in that: The calculation methods for second harmonic suppression and third harmonic suppression are as follows: Step S31: Select the measurement path of the spectrum analyzer, load the measured P1dB, P3dB, and Psat data, and automatically set the spectrum analyzer bandwidth to 100M; Step S32: Start the test, set the frequency to be tested, and set the input power points P1dB, P3dB, and Psat at the corresponding frequency as the input power of the test signal; Step S33: Set and mark the instrument center frequency points for the fundamental, second harmonic, and third harmonic respectively, and read the corresponding values ​​for calculation; Step S34: Calculate the difference and record the second and third harmonic suppression values ​​at each test point.

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