A harmonic test link of a device under test, an active load traction system and a method

Abstract

The present invention relates to the field of radio frequency microwave measurement technology, and specifically to a harmonic test link of a device under test, an active load traction system and a method, the system comprising: a control module and a test link, when testing, the control module first obtains a target mismatch degree, and determines the test signal value of a vector signal source in the test link and the phase adjustable signal value of a first adjustable phase vector signal source according to the target mismatch degree; then, by adjusting the amplitude and phase of the first adjustable phase vector signal source, multiple impedance points on the Smith chart are simulated, and the vector signal source is controlled to send a test signal value, and the first adjustable phase vector signal source is controlled to send a phase adjustable signal value to test the device under test; finally, the harmonic value corresponding to each impedance point is obtained, and according to the harmonic value corresponding to each impedance point, the maximum harmonic of the device under test at the target mismatch degree is obtained. The present invention has a higher impedance adjustment range and accuracy, and a faster adjustment speed.

Description

Technical Field

[0001] The present invention relates to the field of radio frequency microwave measurement technology, and in particular to a harmonic test link of a device under test, an active load traction system and a method. Background Art

[0002] Load pulling is a test technology widely used in the RF and microwave fields. Its core purpose is to test and find the optimal load conditions for device performance (such as power output, efficiency, etc.) by artificially changing the load impedance at the output of RF and microwave devices (such as amplifiers, mixers, etc.). This technology is of great significance for engineers to deeply understand device characteristics, optimize designs, and perform accurate device modeling, especially in wireless communications, radar and other systems.

[0003] Traditional load-pull methods mainly rely on passive load-pull devices. Such devices change the load impedance at the output of the device through tunable passive components (such as capacitors, inductors, transmission lines, etc.). Although passive load-pull devices have the advantages of simple structure and low cost, their impedance adjustment range and accuracy are relatively limited, and they are generally suitable for lower frequency and lower power applications. In addition, since the adjustment of passive components usually relies on mechanical operations, the adjustment speed is relatively slow, which makes it difficult to meet the needs of modern RF and microwave systems for efficient and fast testing.

[0004] Therefore, in the above scheme, the traditional passive load-pull device cannot achieve higher accuracy, wider impedance adjustment range and faster adjustment speed due to its inherent limitations. Summary of the invention

[0005] In view of this, the present invention provides a harmonic test link of a device under test, an active load traction system and method to solve the problem that traditional passive load traction devices cannot achieve higher accuracy, wider impedance adjustment range and faster adjustment speed due to their inherent limitations.

[0006] In a first aspect, the present invention provides a harmonic test link for a device under test, the test link comprising: an adjustable phase vector signal source structure, and a vector signal source, a device under test, a coupler and a vector signal analysis module connected in sequence; the output end of the adjustable phase vector signal source structure is connected to the first input end of the coupler;

[0007] The adjustable phase vector signal source structure is used to send a phase adjustable signal to the vector signal source through the coupler to simulate different load conditions;

[0008] The vector signal source is used to send a test signal to the device under test; the phase-adjustable signal has the same frequency parameters and local oscillator parameters as the test signal;

[0009] The coupler is used to perform partial separation processing on the DUT signal output by the DUT, and output the result to the vector signal analysis module;

[0010] The vector signal analysis module is used to receive and analyze the device under test signal sent by the coupler to obtain harmonic information of the device under test.

[0011] In an optional implementation, the test link further includes a first amplifier and a first circulator;

[0012] The output end of the vector signal source is connected to the second input end of the coupler through the first amplifier, the first circulator and the device under test in sequence;

[0013] The first amplifier is used to amplify the test signal sent by the vector signal source;

[0014] The first circulator is used to transmit the amplified test signal to the device under test in a unidirectional manner.

[0015] In an optional implementation, the adjustable phase vector signal source structure includes a first adjustable phase vector signal source, a second adjustable phase vector signal source and a third adjustable phase vector signal source;

[0016] The output end of the first adjustable phase vector signal source, the output end of the second adjustable phase vector signal source and the output end of the third adjustable phase vector signal source are connected to the first input end of the coupler through a combiner;

[0017] The first adjustable phase vector signal source is used to send a phase adjustable signal to the vector signal source to simulate different load conditions;

[0018] The second adjustable phase vector signal source is used to send a secondary cancellation signal with a phase opposite to the second harmonic of the test link to cancel the second harmonic of the test link;

[0019] The third adjustable phase vector signal source is used to send out a third-order cancellation signal with a phase opposite to the third harmonic of the test link to cancel the third harmonic of the test link.

[0020] In an optional implementation, the test link further includes a second amplifier, a second circulator, a third amplifier, a third circulator, a fourth amplifier, and a fourth circulator;

[0021] The output end of the first adjustable phase vector signal source is connected to the first input end of the coupler through the second amplifier, the second circulator and the combiner in sequence;

[0022] The output end of the second adjustable phase vector signal source is connected to the first input end of the coupler through the third amplifier, the third circulator and the combiner in sequence;

[0023] The output end of the third adjustable phase vector signal source is connected to the first input end of the coupler through the fourth amplifier, the fourth circulator and the combiner in sequence;

[0024] The second amplifier is used to amplify the phase-adjustable signal sent by the first adjustable phase vector signal source; the second circulator is used to unidirectionally transmit the amplified phase-adjustable signal to the combiner;

[0025] The third amplifier is used to amplify the secondary cancellation signal emitted by the second adjustable phase vector signal source; the third circulator is used to unidirectionally transmit the amplified secondary cancellation signal to the combiner;

[0026] The fourth amplifier is used to amplify the third-order cancellation signal emitted by the third adjustable phase vector signal source; the fourth circulator is used to unidirectionally transmit the amplified third-order cancellation signal to the combiner.

[0027] In an optional implementation, the vector signal analysis module includes a first vector signal analysis module and a second vector signal analysis module;

[0028] The coupler is used to perform partial separation processing on the DUT signal output by the DUT to obtain separated harmonic signals and fundamental signals, and output the harmonic signals to the first vector signal analysis module, and output the fundamental signal to the second vector signal analysis module;

[0029] The first vector signal analysis module is used to receive and analyze the harmonic signal emitted by the coupler to obtain harmonic information of the device under test;

[0030] The second vector signal analysis module is used to receive and analyze the fundamental wave signal emitted by the coupler to obtain the signal transmission quality of the test link.

[0031] In an optional implementation, the test link further includes a duplexer and an attenuator;

[0032] The output end of the coupler is connected to the input end of the duplexer, the first output end of the duplexer is connected to the input end of the first vector signal analysis module, and the second output end of the duplexer is connected to the input end of the second vector signal analysis module through the attenuator;

[0033] The duplexer is used to transmit the harmonic signal to the first vector signal analysis module, and transmit the fundamental signal to the second vector signal analysis module through the attenuator;

[0034] The attenuator is used to perform attenuation processing on the fundamental wave signal.

[0035] In a second aspect, the present invention provides an active load traction system, the system comprising a control module and a harmonic test link of a device under test as described above;

[0036] The control module is used for:

[0037] When testing the device under test in the test link, a target mismatch degree is obtained, and a reflection power coefficient is calculated according to the target mismatch degree; the target mismatch degree is used to indicate a target reflection ratio of a test signal during transmission;

[0038] Determining a test signal value of a vector signal source in the test link and a phase adjustable signal value of a first adjustable phase vector signal source according to the reflected power coefficient;

[0039] According to the reflected power coefficient, a plurality of corresponding impedance points are determined on a Smith chart; each impedance point on the Smith chart is used to indicate a different load impedance condition;

[0040] Simulating a plurality of impedance points on the Smith chart by adjusting the amplitude and phase of the first adjustable phase vector signal source, and controlling the vector signal source to send the test signal value, and controlling the first adjustable phase vector signal source to send the phase adjustable signal value, so as to test the device under test;

[0041] The harmonic value corresponding to each impedance point is obtained, and according to the harmonic value corresponding to each impedance point, the maximum harmonic of the device under test at the target mismatch degree is obtained.

[0042] In a third aspect, the present invention provides an active load traction method, which is applied to a control module of an active load traction system as described above, and comprises:

[0043] When testing the device under test in the test link, a target mismatch degree is obtained, and a reflection power coefficient is calculated according to the target mismatch degree; the target mismatch degree is used to indicate a target reflection ratio of a test signal during transmission;

[0044] Determining, according to the reflected power coefficient, a target test signal value to be sent by the vector signal source in the test link and a target phase adjustable signal value to be sent by the first adjustable phase vector signal source;

[0045] According to the reflected power coefficient, a plurality of corresponding impedance points are determined on a Smith chart; each impedance point on the Smith chart is used to indicate a different load impedance condition;

[0046] Simulating a plurality of impedance points on the Smith chart by adjusting the amplitude and phase of the first adjustable phase vector signal source, and controlling the vector signal source to emit the target test signal value, and controlling the first adjustable phase vector signal source to emit the target phase adjustable signal value, so as to test the device under test;

[0047] The harmonic value corresponding to each impedance point is obtained, and according to the harmonic value corresponding to each impedance point, the maximum harmonic of the device under test at the target mismatch degree is obtained.

[0048] In an optional implementation manner, before testing the device under test in the test link, the method further includes:

[0049] Under the condition that the device under test is removed from the test link, a plurality of frequency points within a signal frequency range are obtained;

[0050] For each frequency point, the test signal value emitted by the vector signal source and the first received signal value corresponding to the specific connection point are recorded to construct a first calibration table, and the phase-adjustable signal value emitted by the first adjustable phase vector signal source and the second received signal value corresponding to the specific connection point are recorded to construct a second calibration table;

[0051] The second adjustable phase vector signal source is controlled to emit a secondary cancellation signal with a phase opposite to the second harmonic of the test link to cancel the second harmonic of the test link, and the third adjustable phase vector signal source is controlled to emit a third cancellation signal with a phase opposite to the third harmonic of the test link to cancel the third harmonic of the test link.

[0052] In an optional implementation, determining, according to the reflected power coefficient, a target test signal value to be sent by the vector signal source in the test link and a target phase adjustable signal value to be sent by the first adjustable phase vector signal source includes:

[0053] determining, from the first calibration table, a target test signal value to be sent by a vector signal source in the test link according to the reflected power coefficient;

[0054] According to the reflected power coefficient, a target phase adjustable signal value to be emitted by the first adjustable phase vector signal source is determined from the second calibration table.

[0055] In a fourth aspect, the present invention provides an active load traction device, the device is applied to a control module of an active load traction system as described above, and the method comprises:

[0056] A target mismatch degree acquisition module is used to acquire a target mismatch degree when testing the device under test in the test link, and calculate a reflection power coefficient according to the target mismatch degree; the target mismatch degree is used to indicate a target reflection ratio of a test signal during transmission;

[0057] A signal acquisition module to be sent, used to determine the target test signal value to be sent by the vector signal source in the test link and the target phase adjustable signal value to be sent by the first adjustable phase vector signal source according to the reflected power coefficient;

[0058] An impedance point determination module, used to determine a plurality of corresponding impedance points on a Smith chart according to the reflected power coefficient; each impedance point on the Smith chart is used to indicate a different load impedance condition;

[0059] A testing module, configured to simulate a plurality of impedance points on the Smith chart by adjusting the amplitude and phase of the first adjustable phase vector signal source, and control the vector signal source to emit the target test signal value, and control the first adjustable phase vector signal source to emit the target phase adjustable signal value, so as to test the device under test;

[0060] The maximum harmonic acquisition module is used to acquire the harmonic value corresponding to each impedance point, and acquire the maximum harmonic of the device under test at the target mismatch level according to the harmonic value corresponding to each impedance point.

[0061] In a fifth aspect, the present invention provides a computer device, comprising: a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the computer instructions to execute an active load traction method according to the first aspect or any corresponding embodiment thereof.

[0062] In a sixth aspect, the present invention provides a computer-readable storage medium having computer instructions stored thereon, the computer instructions being used to enable a computer to execute an active load traction method according to the first aspect or any corresponding embodiment thereof.

[0063] In a seventh aspect, the present invention provides a computer program product, comprising computer instructions for causing a computer to execute an active load traction method according to the first aspect or any corresponding embodiment thereof.

[0064] The technical solution provided by the present invention may include the following beneficial effects:

[0065] The present invention can flexibly adjust the phase and amplitude of the signal by means of an adjustable phase vector signal source structure. In this way, many different impedance points on the Smith chart can be simulated, and a wider impedance adjustment range can be achieved. Compared with traditional methods, the present invention can more accurately set various complex load conditions, providing strong support for testing the performance of the device under test under different loads, thereby greatly improving the accuracy of impedance adjustment.

[0066] The present invention records the signal values ​​of the vector signal source and the adjustable phase vector signal source at a specific connection point by removing the device under test before testing, providing an accurate reference basis for subsequent testing. At the same time, the second adjustable phase vector signal source and the third adjustable phase vector signal source are used to offset the second and third harmonics of the link, effectively removing the harmonic interference caused by the link, which not only improves the accuracy of the test, but also after the calibration is completed, the signal source can be directly adjusted according to the calibration results in subsequent tests, greatly accelerating the test speed and improving the test efficiency.

[0067] The present invention can comprehensively evaluate the performance of the device under test by obtaining harmonic information of the device under test under different mismatch degrees, especially determining the maximum harmonic, and simulate multiple impedance points on the Smith chart for testing to obtain the working state of the device under different load conditions, with a higher impedance adjustment range and accuracy and a faster adjustment speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0069] Figure 1 shows a schematic diagram of the Smith chart under passive load pull;

[0070] Figure 2 A schematic diagram of the normal load-pull region of the Smith chart is shown;

[0071] Figure 3 A schematic diagram of the moving load pull region of the Smith chart is shown;

[0072] Figure 4 is a structural schematic diagram of a harmonic test link of a device under test according to an embodiment of the present invention;

[0073] Figure 5 is a schematic structural diagram of an active load traction system according to an embodiment of the present invention;

[0074] Figure 6 is a flow chart of an active load traction method according to an embodiment of the present invention;

[0075] Figure 7 is a schematic diagram of the locations of specific connection points of a harmonic test link of a device under test according to an embodiment of the present invention;

[0076] Figure 8 A schematic diagram of point C on the Smith chart is shown;

[0077] Fig. 9 A schematic diagram of VSWR circle drawing on a Smith chart is shown;

[0078] Fig.10 is a structural block diagram of an active load traction device according to an embodiment of the present invention;

[0079] Fig.11 It is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0080] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0081] It should be noted that the essence of load pulling is to create an impedance network to present a specific impedance value. The main method of passive load pulling is to use a set of adjustable capacitors, inductors and resistors to form a network to achieve the construction of a specific impedance value. The construction of this impedance value has certain limitations. For example, the goal is to build a fully reflected short-circuit impedance. The short-circuit state can be constructed using a load-pulling device, but due to the link insertion loss problem, it is difficult to construct a fully reflected state in actual use. Specifically, the fully reflected network should not have any insertion loss, that is, the amplitude of the incident signal and the reflected signal are equal. In fact, since there can be no insertion loss on the line, the amplitude of the reflected signal is smaller than the amplitude of the incident signal. That is to say, if the incident signal is 10dBm, the reflected signal may be 9dBm or 8dBm, which means that the impedance value will definitely not reach the edge of the Smith chart. Please refer to Figure 1 The Smith chart diagram of passive load pull is shown in Figure 1 As shown in the figure, if the impedance point that the passive traction device needs to build is point A, but due to the insertion loss of the passive traction device itself, the maximum limit can only be built to point B, so the impedance network area that the actual load traction device can build will be somewhat compressed. Figure 2Schematic diagram of the normal load-pull region of the Smith chart.

[0082] In fact, if the link matching is taken into account, the area that the actual load-pull device can reach will be further compressed. Assuming that the link matching is biased towards the capacitive area, that is, the bottom, and changes in the direction of increasing resistance, that is, the right, then the area that can be adjusted by this load-pull device will also move to the bottom right. See here Figure 3 The moving load pull region of the Smith chart is shown in Figure 2. Figure 3 As shown, the area inside the grid circle is the load-pulling area that is shrunk due to link matching and insertion loss, while the area outside the grid circle cannot be reached no matter how the load-pulling device is adjusted.

[0083] In the present invention, active load pulling can achieve total reflection, and can achieve impedance simulation of short circuit or open circuit by compensating for cable loss, and can construct the impedance of any point on the Smith original diagram, so it is more versatile in function. The present invention uses a continuous wave vector source with adjustable phase and amplitude to simulate an adjustable load (i.e., a first adjustable phase vector signal source), and when measuring, it shares the local oscillator with the vector signal source to ensure the stability of the transmitted signal, and adjusts the voltage standing wave ratio (VSWR) by adjusting the amplitude, and covers the angle on the phase plane by adjusting the phase. When the device under test is a switch chip in a mobile phone, it is necessary to test the harmonic characteristics under mismatch conditions, that is, to find the maximum harmonic of the device under test under a certain degree of mismatch.

[0084] The first adjustable phase vector signal source needs to share the local oscillator with the vector signal source and trigger synchronously to ensure the repeatability of the phase. The first adjustable phase vector signal source sends out a signal of the corresponding frequency. By adjusting the phase and amplitude, different points on the Smith chart can be simulated. Since the signal sent by the first adjustable phase vector signal source can be greater than the signal reflected from the right end of the device under test, this can compensate for the signal attenuation caused by insertion loss, so that points closer to the edge of the Smith first adjustable phase vector signal source can be simulated.

[0085] In this embodiment, a harmonic test link of a device under test is provided. Figure 4 is a schematic diagram of a structure of a harmonic test link of a device under test according to an embodiment of the present invention. Figure 4 As shown, the test link includes: an adjustable phase vector signal source structure, and a vector signal source, a device under test, a coupler and a vector signal analysis module connected in sequence; the output end of the adjustable phase vector signal source structure is connected to the first input end of the coupler;

[0086] The adjustable phase vector signal source structure is used to send a phase adjustable signal to the vector signal source through the coupler to simulate different load conditions;

[0087] The vector signal source is used to send a test signal to the device under test; the phase-adjustable signal has the same frequency parameters and local oscillator parameters as the test signal;

[0088] The coupler is used to perform partial separation processing on the DUT signal output by the DUT, and output the result to the vector signal analysis module;

[0089] The vector signal analysis module is used to receive and analyze the device under test signal sent by the coupler to obtain harmonic information of the device under test.

[0090] In an optional implementation, the test link further includes a first amplifier (i.e. Figure 4 Amplifier 1 in the circuit) and the first circulator (i.e. Figure 4 Circulator 1 in);

[0091] The output end of the vector signal source is connected to the second input end of the coupler through the first amplifier, the first circulator and the device under test in sequence;

[0092] The first amplifier is used to amplify the test signal sent by the vector signal source;

[0093] The first circulator is used for unidirectionally transmitting the amplified test signal to the device under test.

[0094] Furthermore, the first amplifier amplifies the test signal emitted by the vector signal source. The first amplifier can increase the power of the test signal to reach an appropriate power level, ensuring that the device under test can be effectively stimulated, thereby more accurately testing its performance. The first circulator transmits the amplified test signal unidirectionally to the device under test. The circulator is a non-reciprocal microwave device based on magnetic materials such as ferrite, and has a unidirectional transmission characteristic. In this test link, the first circulator ensures that the amplified signal can only be transmitted from one port (the port connected to the first amplifier) ​​to the other port (the port connected to the device under test), and not in the reverse direction, so as to prevent the signal reflected from the device under test from returning to the first amplifier or even the vector signal source, and to avoid interference or damage to the signal source and amplifier by the reflected signal.

[0095] In an optional implementation, the adjustable phase vector signal source structure includes a first adjustable phase vector signal source (ie Figure 4 The adjustable phase vector signal source 1 in the embodiment of the present invention), the second adjustable phase vector signal source (i.e. Figure 4 The adjustable phase vector signal source 2) and the third adjustable phase vector signal source (ie Figure 4 Adjustable phase vector signal source 3);

[0096] The output end of the first adjustable phase vector signal source, the output end of the second adjustable phase vector signal source and the output end of the third adjustable phase vector signal source are connected to the first input end of the coupler through a combiner;

[0097] The first adjustable phase vector signal source is used to send a phase adjustable signal to the vector signal source to simulate different load conditions; the phase adjustable signal sent by the first adjustable phase vector signal source is sent to the vector signal source through the second amplifier, the second circulator, the combiner, the coupler, the device under test, the first circulator, and the first amplifier in sequence;

[0098] The second adjustable phase vector signal source is used to emit a secondary cancellation signal with a phase opposite to the second harmonic of the test link to cancel the second harmonic of the test link; the secondary cancellation signal emitted by the second adjustable phase vector signal source is sequentially sent to the first vector signal analysis module through the third amplifier, the third circulator, the combiner, the coupler, and the duplexer;

[0099] The third adjustable phase vector signal source is used to emit a third-order cancellation signal with a phase opposite to the third harmonic of the test link to cancel the third harmonic of the test link; the third-order cancellation signal emitted by the third adjustable phase vector signal source is sequentially sent to the first vector signal analysis module through a fourth amplifier, a fourth circulator, a combiner, a coupler, and a duplexer.

[0100] Furthermore, the output ends of the three adjustable phase vector signal sources of the adjustable phase vector signal source structure are connected to a combiner, which combines their signals into one and then transmits them to the first input end of the coupler. The first adjustable phase vector signal source function simulates different load conditions by sending out phase-adjustable signals. Changing the signal phase can equivalently change the electrical characteristics of the load, thereby simulating different actual load conditions. The function of the second adjustable phase vector signal source is to generate a secondary cancellation signal with an anti-phase to the second harmonic of the test link. In electronic circuits, the signal transmission process often generates harmonics. The second harmonic is a harmonic component with twice the signal frequency. These harmonics may interfere with normal signal transmission and affect the accuracy of the test results. The anti-phase signal emitted by the second adjustable phase vector signal source is superimposed on the second harmonic. When the amplitudes of the two are equal and the phases are opposite, they will cancel each other out, thereby reducing the interference of the second harmonic on the test and improving the test accuracy. The function of the third adjustable phase vector signal source is similar to that of the second adjustable phase vector signal source. The third adjustable phase vector signal source sends out a third-order cancellation signal with an anti-phase to the third harmonic of the test link. The third harmonic is a harmonic component with three times the signal frequency, which will also interfere with the test. By sending out an anti-phase signal to cancel the third harmonic, the test environment is further optimized to ensure that the test results can more truly reflect the performance of the device under test.

[0101] In an optional implementation, the test link further includes a second amplifier (i.e. Figure 4 Amplifier 2 in the second circulator (i.e. Figure 4 Circulator 2 in the circulator), the third amplifier (i.e. Figure 4 Amplifier 3 in the third circulator (i.e. Figure 4 Circulator 3), the fourth amplifier (i.e. Figure 4 The amplifier 4 in the Figure 4 Circulator 4);

[0102] The output end of the first adjustable phase vector signal source is connected to the first input end of the coupler through the second amplifier, the second circulator and the combiner in sequence;

[0103] The output end of the second adjustable phase vector signal source is connected to the first input end of the coupler through the third amplifier, the third circulator and the combiner in sequence;

[0104] The output end of the third adjustable phase vector signal source is connected to the first input end of the coupler through the fourth amplifier, the fourth circulator and the combiner in sequence;

[0105] The second amplifier is used to amplify the phase-adjustable signal sent by the first adjustable phase vector signal source; the second circulator is used to unidirectionally transmit the amplified phase-adjustable signal to the combiner;

[0106] The third amplifier is used to amplify the secondary cancellation signal emitted by the second adjustable phase vector signal source; the third circulator is used to unidirectionally transmit the amplified secondary cancellation signal to the combiner;

[0107] The fourth amplifier is used to amplify the third-order cancellation signal emitted by the third adjustable phase vector signal source; the fourth circulator is used to unidirectionally transmit the amplified third-order cancellation signal to the combiner.

[0108] In an optional implementation, the vector signal analysis module includes a first vector signal analysis module (ie Figure 4 The vector signal analysis module 1) and the second vector signal analysis module (i.e. Figure 4 Vector signal analysis module 2);

[0109] The coupler is used to perform partial separation processing on the device under test signal output by the device under test to obtain separated harmonic signals and fundamental wave signals, and output the harmonic signals to the first vector signal analysis module, and output the fundamental wave signals to the second vector signal analysis module;

[0110] The first vector signal analysis module is used to receive and analyze the harmonic signal emitted by the coupler to obtain harmonic information of the device under test;

[0111] The second vector signal analysis module is used to receive and analyze the fundamental wave signal sent by the coupler to obtain the signal transmission quality of the test link.

[0112] Furthermore, the vector signal analysis module is subdivided into a first vector signal analysis module and a second vector signal analysis module, which work together to analyze the signal output by the device under test from different angles. The first vector signal analysis module is mainly used to process the harmonic signal separated by the coupler. By analyzing the characteristics of the harmonic signal, the first vector signal analysis module can obtain the nonlinearity and distortion of the device under test during the signal processing process, and then evaluate the performance of the device under test.

[0113] The second vector signal analysis module is used to process the fundamental signal separated by the coupler. The fundamental signal is the main frequency component of the original test signal, and its transmission quality directly reflects the basic performance of the test link. The second vector signal analysis module analyzes the fundamental signal to evaluate the transmission capability of the test link for the fundamental signal, and determines whether the test link has problems such as signal attenuation and interference, so as to determine the signal transmission quality of the entire test link.

[0114] In an optional implementation, the test link further includes a duplexer and an attenuator;

[0115] The output end of the coupler is connected to the input end of the duplexer, the first output end of the duplexer is connected to the input end of the first vector signal analysis module, and the second output end of the duplexer is connected to the input end of the second vector signal analysis module through the attenuator;

[0116] The duplexer is used to transmit the harmonic signal to the first vector signal analysis module, and transmit the fundamental signal to the second vector signal analysis module through the attenuator;

[0117] The attenuator is used to perform attenuation processing on the fundamental wave signal.

[0118] Furthermore, the duplexer plays a key role in signal separation and transmission in the test link. It receives the mixed signal (including harmonic signal and fundamental signal) output from the coupler, and uses its own filtering characteristics to accurately guide the harmonic signal to the first vector signal analysis module, and guide the fundamental signal to the second vector signal analysis module, ensuring that signals with different frequency components can be accurately transmitted to the corresponding analysis module, avoiding signal confusion. The attenuator is used to perform early attenuation processing on the fundamental signal transmitted to the second vector signal analysis module. In actual testing, the strength of the fundamental signal may be too high, exceeding the optimal measurement range of the second vector signal analysis module. If the unattenuated fundamental signal is directly input into the analysis module, it may cause inaccurate measurement or even damage the analysis module. The attenuator reduces the amplitude of the fundamental signal by a certain proportion, so that the strength of the fundamental signal is within the range that the second vector signal analysis module can accurately measure and analyze, thereby ensuring that the analysis result of the fundamental signal is accurate and reliable.

[0119] Further, such as Figure 4As shown, in this embodiment, the vector signal source is first connected to the first amplifier, and the amplified signal is transmitted to the device under test through the first circulator. The output signal of the device under test is connected to the coupler, and the coupler divides the signal into two paths. One signal is connected to the attenuator and the second vector signal analysis module after passing through the duplexer. The other signal is directly connected to the first vector signal analysis module through the duplexer. At the same time, this embodiment is provided with three adjustable phase vector signal sources (respectively, the first adjustable phase vector signal source, the second adjustable phase vector signal source, and the third adjustable phase vector signal source), and each adjustable phase vector signal source is sequentially connected to an amplifier (respectively, the second amplifier, the third amplifier, and the fourth amplifier) ​​and a circulator (respectively, the second circulator, the third circulator, and the fourth circulator), and then the three signals are merged through a combiner and finally connected to the coupler. During the test, the vector signal source of this embodiment sends a test signal through the first amplifier, the first circulator, the device under test, and the coupler to enter the duplexer. The separated fundamental wave signal goes through the upper route to enter the attenuator and then enters the second vector signal analysis module. The harmonics are relatively small, so it directly goes through the lower route to enter the first vector signal analysis module, and the harmonics of the switch can be measured. However, the harmonics measured at this time include the harmonics of the switch of the device under test and the harmonics of the test link. Therefore, before the test, this embodiment also needs to perform a calibration operation, such as removing the device under test first, directly connecting the circulator and the coupler first, and sending a secondary cancellation signal with a phase opposite to the second harmonic of the link to the vector signal source through the second adjustable phase vector signal source to cancel the second harmonic of the link, and sending a third cancellation signal with a phase opposite to the third harmonic of the link to the vector signal source through the third adjustable phase vector signal source to cancel the third harmonic of the link. Observe that the first vector signal analysis module receives no signal, only a background noise signal, which means that the harmonics have been filtered out. Then the device under test is connected, and the harmonics normally measured based on the above test link are the harmonics caused only by the device under test.

[0120] In summary, this embodiment can flexibly adjust the phase and amplitude of the signal by means of an adjustable phase vector signal source structure. In this way, it is possible to simulate many different impedance points on the Smith chart, with a wider impedance adjustment range. Compared with the traditional method, the present invention can more accurately set various complex load conditions, providing strong support for testing the performance of the device under test under different loads, thereby greatly improving the accuracy of impedance adjustment.

[0121] This embodiment records the signal values ​​of the vector signal source and the adjustable phase vector signal source at a specific connection point by removing the device under test before testing, providing an accurate reference for subsequent testing. At the same time, the second adjustable phase vector signal source and the third adjustable phase vector signal source are used to offset the second and third harmonics of the link, effectively removing the harmonic interference caused by the link, which not only improves the accuracy of the test, but also after the calibration is completed, the signal source can be directly adjusted according to the calibration results in subsequent tests, which greatly speeds up the test speed and improves the test efficiency.

[0122] In this embodiment, an active load traction system is provided. Figure 5 is a schematic diagram of the structure of an active load traction system according to an embodiment of the present invention. Figure 5 As shown, the system includes a control module and Figure 4 A harmonic test link of a device under test is shown; the control module is used for:

[0123] When testing the device under test in the test link, a target mismatch degree is obtained, and a reflection power coefficient is calculated according to the target mismatch degree; the target mismatch degree is used to indicate a target reflection ratio of the test signal during transmission;

[0124] Determine, according to the reflected power coefficient, a test signal value of the vector signal source in the test link and a phase adjustable signal value of the first adjustable phase vector signal source;

[0125] According to the reflected power coefficient, a plurality of corresponding impedance points are determined on the Smith chart; each impedance point on the Smith chart is used to indicate a different load impedance condition;

[0126] Simulating multiple impedance points on the Smith chart by adjusting the amplitude and phase of the first adjustable phase vector signal source, and controlling the vector signal source to send the test signal value, and controlling the first adjustable phase vector signal source to send the phase adjustable signal value to test the device under test;

[0127] The harmonic value corresponding to each impedance point is obtained, and according to the harmonic value corresponding to each impedance point, the maximum harmonic of the device under test at the target mismatch degree is obtained.

[0128] Furthermore, the active load traction system of this embodiment is composed of a control module and a harmonic test link of the device under test. The harmonic test link of the device under test provides a basis for physical connection and signal processing for actual signal testing and analysis of the device under test, while the control module is used to accurately control the entire test process and calculate parameters.

[0129] The target mismatch degree represents the reflection ratio that the test signal is expected to achieve during the transmission process. In actual RF and microwave circuits, it is difficult to achieve an ideal complete matching state between the load and the transmission line, and there will always be a certain degree of mismatch. This target mismatch degree is set manually according to the test requirements and is used to simulate different actual application scenarios. After the control module obtains the target mismatch degree, it calculates the reflection power coefficient according to a specific mathematical relationship. The reflection power coefficient is an important indicator to measure the degree of signal reflection. By calculating the reflection power coefficient, the reflection of the signal during the transmission process can be quantified. Based on the calculated reflection power coefficient, the control module determines the test signal value of the vector signal source and the phase adjustable signal value of the first adjustable phase vector signal source. The test signal value of the vector signal source determines the strength of the excitation signal input to the device under test, and the phase adjustable signal value of the first adjustable phase vector signal source is used to simulate the impact of different loads on the device under test.

[0130] The Smith chart is a tool used to analyze impedance characteristics in RF and microwave engineering. The control module determines multiple corresponding impedance points on the Smith chart based on the reflected power coefficient. Each impedance point on the chart corresponds to a specific load impedance condition. By finding these points on the chart, various actual load conditions can be simulated.

[0131] The control module simulates multiple impedance points determined on the Smith chart by adjusting the amplitude and phase of the first adjustable phase vector signal source. Changing the amplitude and phase of the first adjustable phase vector signal source can equivalently change the load impedance faced by the device under test, thereby simulating different load conditions.

[0132] After simulating the impedance point, the control module controls the vector signal source to send out the previously determined test signal value, and at the same time controls the first adjustable phase vector signal source to send out the corresponding phase adjustable signal value, so that the device under test works under the simulated load conditions, thereby performing actual testing. During the simulation test at different impedance points, the control module obtains the harmonic values ​​corresponding to each impedance point. These harmonic values ​​reflect the harmonic generation of the device under test under different load conditions. Based on the harmonic values ​​corresponding to each impedance point obtained, the control module finds the maximum value. This maximum harmonic value represents the worst case of harmonic generation by the device under test under the target mismatch degree. By determining the maximum harmonic, the performance limit of the device under test under specific mismatch conditions can be evaluated.

[0133] According to an embodiment of the present invention, an active load traction method embodiment is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0134] In this embodiment, an active load traction method is provided, which is applied to Figure 5 In the control module of an active load traction system shown in FIG. Figure 6 is a flow chart of an active load traction method according to an embodiment of the present invention. Figure 6 As shown, the process includes the following steps:

[0135] Step S601, when testing the device under test in the test link, obtain a target mismatch degree, and calculate a reflection power coefficient according to the target mismatch degree; the target mismatch degree is used to indicate a target reflection ratio of a test signal during transmission.

[0136] In an optional implementation manner, before testing the device under test in the test link, the method further includes:

[0137] Under the condition that the device under test is removed from the test link, a plurality of frequency points within the signal frequency range are obtained;

[0138] For each frequency point, the test signal value emitted by the vector signal source and the first received signal value corresponding to the specific connection point are recorded to construct a first calibration table, and the phase-adjustable signal value emitted by the first adjustable phase vector signal source and the second received signal value corresponding to the specific connection point are recorded to construct a second calibration table;

[0139] The specific connection point may be arranged on the link at the second input end of the coupler.

[0140] The second adjustable phase vector signal source is controlled to emit a secondary cancellation signal with a phase opposite to the second harmonic of the test link to cancel the second harmonic of the test link, and the third adjustable phase vector signal source is controlled to emit a third cancellation signal with a phase opposite to the third harmonic of the test link to cancel the third harmonic of the test link.

[0141] Furthermore, before actually testing the device under test in the test link, the present embodiment needs to calibrate the test link first. At this time, the device under test is removed from the test link, and multiple frequency points are selected in the entire signal frequency range. The selection of these frequency points should be representative and cover the frequency range that may be involved in the actual operation of the device under test, so that the performance of the test link at different frequencies can be calibrated later. For each selected frequency point, the test signal value emitted by the vector signal source and the first received signal value received at a specific connection point (here set on the link at the second input end of the coupler) are recorded respectively. In this way, the correspondence between the signal emitted by the vector signal source at different frequencies and the received signal at a specific connection point is established, thereby constructing a first calibration table. The table can reflect the connection between the test signal emitted by the vector signal source and the received signal (i.e., the first received signal value) at a specific connection point under different frequency conditions. Similarly, for each frequency point, the phase-adjustable signal value emitted by the first adjustable phase vector signal source and the second received signal value corresponding to the specific connection point are recorded to construct a second calibration table. This table reflects the relationship between the phase adjustable signal emitted by the first adjustable phase vector signal source and the received signal at the specific connection point at this time (i.e., the second received signal value). When the reflected power coefficient is known (the reflected power coefficient is the ratio between the signal value emitted by the first adjustable phase vector signal source and finally reaching the vector signal source via the coupler and the signal value emitted by the vector signal source and finally reaching the second vector signal analysis module, i.e., the ratio between the second received signal value and the first received signal value), it can be used to determine the target test signal value emitted by the vector signal source and the target phase adjustable signal value that the first adjustable phase vector signal source should emit, so as to ensure that it can work with the vector signal source to simulate accurate load conditions. In the test link, second harmonics and third harmonics are generated during signal transmission, and these harmonics will interfere with the accuracy of the test results. Therefore, the second adjustable phase vector signal source is controlled to emit a secondary cancellation signal with an anti-phase to the second harmonic of the test link. When the secondary cancellation signal and the second harmonic have equal amplitude and opposite phase, the two cancel each other, thereby eliminating the influence of the second harmonic. Similarly, the third adjustable phase vector signal source is controlled to send a third-order cancellation signal with a phase opposite to the third harmonic of the test link to cancel the third harmonic, thereby improving the purity of the test link and the reliability of the test result.

[0142] The calibration work in this embodiment has two main purposes: the first is to calibrate to the end face of the device under test, and the second is to remove the harmonic influence caused by the link. Figure 7The schematic diagram of the location of specific connection points of a harmonic test link of a device under test is shown. When calibrating, first remove the device under test and replace it with a through-piece or directly connect the left and right ends of the device under test. Confirm the frequently used signal frequency range, such as 1dBm to 30dBm. You can take a point every 1dBm, and the vector signal source sends a 1dBm signal. Then use a network analyzer to monitor the specific connection point (i.e. Figure 7 The signal value of point A in the first calibration table is recorded, and then the corresponding situations of all signal values ​​are recorded in turn, and recorded in the first calibration table, so that when the signal value of point A needs to be guaranteed, the specific test signal value that needs to be sent from the vector signal source can be directly obtained from the first calibration table. Similarly, in this embodiment, a first adjustable phase vector signal source is used to send out a plurality of phase adjustable signals, and the signal value of point A is detected and recorded by a network analyzer, and then the corresponding situations of all signal values ​​are recorded in turn, and recorded in the second calibration table, so that when the signal value of point A needs to be guaranteed, the specific phase adjustable signal value that needs to be sent from the first adjustable phase vector signal source can be directly obtained from the second calibration table.

[0143] When the vector signal source sends out a signal, the test link will also generate harmonics. The main signal (that is, the fundamental signal) will enter the attenuator from the second output end of the duplexer and then enter the second vector signal analysis module; the harmonic signal will enter the first vector signal analysis module from the first output end of the duplexer. The second adjustable phase vector signal source is continuously adjusted to offset the second harmonic of the link, and the third adjustable phase vector signal source is continuously adjusted to offset the third harmonic of the link. If the first vector signal analysis module receives no signal but only a background noise signal, it means that the harmonics have been filtered out. Calibration is a complex process. All impedance points on a circle on the Smith chart are calibrated to filter out all harmonics. In this way, when the vector signal source sends out a test signal at will, the signals of the second adjustable phase vector signal source and the third adjustable phase vector signal source can be directly adjusted to filter out the harmonics of the entire test link.

[0144] Furthermore, in this embodiment, when the device under test is connected to the test link during the test, the degree of mismatch needs to be determined first, and the degree of mismatch is expressed by voltage standing wave ratio (VSWR). By controlling the first adjustable phase vector signal source to control the signal size transmitted to the vector signal source, and calculating with the signal value actually transmitted by the vector signal source to the second vector analysis module, a specific VSWR can be determined (that is, the degree of mismatch is obtained by the phase adjustable signal value sent by the first adjustable phase vector signal source to the vector signal source and the test signal value transmitted by the vector signal source to the second vector analysis module). This embodiment has a higher impedance adjustment range and accuracy, and a faster adjustment speed.

[0145] If the VSWR is known to be 1.5, the worst harmonic of the switch needs to be obtained; when VSWR=1.5, the calculated reflected power coefficient is 0.04, that is, if the signal value sent by the vector signal source and finally reaching the second vector signal analysis module is 10dBm, the signal value sent from the first adjustable phase vector signal source and finally reaching the vector signal source through the coupler is 0.4dBm (the reflected power coefficient is the ratio between the signal value sent by the first adjustable phase vector signal source and finally reaching the vector signal source through the coupler and the signal value sent by the vector signal source and finally reaching the second vector signal analysis module, that is, the ratio between the second received signal value and the first received signal value). Please refer to Figure 8 The schematic diagram of point C on the Smith chart is shown. This point can be marked on the Smith chart, for example, this point is point C. Fig. 9 The schematic diagram of VSWR circle drawing on the Smith chart is shown in the figure. A circle is drawn with the center of the Smith chart as the center and the distance from the center to point C as the radius, as shown in the figure below. Fig. 9 As shown, the VSWR of each point on this circle is equal, but the impedance and phase are different. Then adjust the phase through load pulling to find the maximum harmonic value of the switch. Then it is necessary to find n impedance points with different phases on this circle to maximize the harmonics of the device under test. If a passive load pulling device is used, the internal adjustment is mechanical, so the speed is slow. Considering the time problem, the value of n will not be very large. Generally, 10-20 points will be selected. Each time an impedance point is selected, the harmonics of the switch are measured once. The harmonics of these 10 to 20 points are measured in turn to find the largest harmonic. This embodiment has no limitation, and hundreds or thousands of points can be taken. After measuring the harmonics of each impedance point, the maximum harmonic can be found, and the test of the maximum harmonic is more accurate.

[0146] Step S602: determining a target test signal value to be sent by a vector signal source in the test link and a target phase adjustable signal value to be sent by a first adjustable phase vector signal source according to the reflected power coefficient.

[0147] In an optional implementation, step S602 includes:

[0148] Determining, from the first calibration table, a target test signal value to be sent by a vector signal source in the test link according to the reflected power coefficient;

[0149] According to the reflected power coefficient, a target phase adjustable signal value to be emitted by the first adjustable phase vector signal source is determined from the second calibration table.

[0150] Furthermore, in the actual test process, after the reflection power coefficient is calculated, the signal value emitted by the vector signal source and finally reaching the second vector signal analysis module (i.e., the first received signal value corresponding to the specific connection point) and the signal value emitted by the first adjustable phase vector signal source and finally reaching the vector signal source via the coupler (i.e., the second received signal value corresponding to the specific connection point) can be determined based on the reflection power coefficient. Based on the first received signal value, the target test signal value to be emitted by the vector signal source corresponding to the reflection power coefficient can be found from the first calibration table. Since the first calibration table records the correspondence between the signal emitted by the vector signal source at different frequencies and the signal received at a specific connection point, based on the intrinsic connection between the reflection power coefficient and the received signal value, the output signal value of the vector signal source suitable for the current test conditions can be accurately obtained from the first calibration table to ensure that a suitable excitation signal is provided for the device under test.

[0151] After obtaining the signal value emitted by the first adjustable phase vector signal source and finally reaching the vector signal source via the coupler (i.e., the second received signal value corresponding to the specific connection point), based on the second received signal value, the target phase adjustable signal value to be emitted by the first adjustable phase vector signal source can be determined from the second calibration table. This is because the second calibration table records the relationship between the signal emitted by the first adjustable phase vector signal source and the received signal at the specific connection point under different conditions. Through the reflected power coefficient and the determined second received signal value, the output signal value of the first adjustable phase vector signal source that matches it can be found, so that the phase adjustable signal output by the signal source cooperates with the output signal of the vector signal source, accurately simulating the required load conditions, and providing a guarantee for accurately testing the performance of the device under test.

[0152] Furthermore, during the test, the present embodiment can determine the target test signal value to be sent by the vector signal source in the test link and the target phase adjustable signal value to be sent by the first adjustable phase vector signal source according to the reflected power coefficient. For example, when the VSWR is 8, the transmission power ratio can be calculated to be 0.6049, and the reflected power coefficient is the ratio between the signal value sent by the first adjustable phase vector signal source to the vector signal source via the coupler and the signal value sent by the vector signal source and finally reaching the second vector signal analysis module; that is, when the input signal is 20dBm, the reflected signal is 17.82dBm. At this time, you can check the first calibration table and use the vector signal source to send a suitable test signal to ensure that the signal value received by point A from the vector signal source is 20dBm. You can check the second calibration table and use the vector signal source to send a suitable signal to ensure that the phase-adjustable signal value received by point A from the first adjustable phase vector signal source is 17.82dBm. This ensures that the voltage standing wave ratio of point A, the right endpoint of the device under test, is 8. At this time, the impedance and phase of the first adjustable phase vector signal source can be marked on the Smith chart to indicate the corresponding impedance point. Then, by adjusting the phase, multiple impedance points can be measured in sequence, and the harmonics of the device under test can be measured in sequence. The worst harmonic value can be found by observing the signal size of the first vector signal analysis module.

[0153] Step S603: determining a plurality of corresponding impedance points on a Smith chart according to the reflected power coefficient; each impedance point on the Smith chart is used to indicate a different load impedance condition.

[0154] Furthermore, the reflected power coefficient is a parameter that reflects the signal reflection situation. The Smith chart graphically shows the relationship between the normalized impedance and the reflection coefficient. When the reflected power coefficient is known, it can be converted into the reflection coefficient by the corresponding formula. Therefore, after the reflection coefficient is calculated, the corresponding normalized impedance value can be calculated. These normalized impedances correspond to specific impedance points on the Smith chart, so multiple impedance points can be determined on the Smith chart. Since different normalized impedance values ​​mean different combinations of load resistance and reactance, corresponding to different load states, these impedance points represent different load impedance conditions. For example, on the Smith chart, the center of the circle indicates a complete match, and the closer to the circumference, the greater the mismatch. In this way, the circuit characteristics under various load conditions can be intuitively observed and analyzed.

[0155] Step S604, simulating multiple impedance points on the Smith chart by adjusting the amplitude and phase of the first adjustable phase vector signal source, and controlling the vector signal source to emit the target test signal value, and controlling the first adjustable phase vector signal source to emit the target phase adjustable signal value to test the device under test.

[0156] Furthermore, since the signal sent by the first adjustable phase vector signal source will affect the load condition of the device under test, changing its amplitude and phase is equivalent to changing the equivalent impedance of the load. The amplitude and phase of the first adjustable phase vector signal source can be adjusted to simulate multiple impedance points determined on the Smith chart. For example, adjusting the amplitude and phase can change the size and phase of the reflected wave, thereby simulating the reflection of different loads on the signal and realizing the simulation of different load conditions.

[0157] This embodiment also controls the vector signal source to send out a target test signal value, and controls the first adjustable phase vector signal source to send out a target phase adjustable signal value. The test signal of the vector signal source is a signal that stimulates the device under test, and the phase adjustable signal of the first adjustable phase vector signal source affects the load condition. The two work together to make the device under test run under simulated load conditions, so that the performance of the device under test under different loads can be observed and measured.

[0158] Step S605, obtaining the harmonic value corresponding to each impedance point, and obtaining the maximum harmonic of the device under test at the target mismatch level according to the harmonic value corresponding to each impedance point.

[0159] Furthermore, during the test, when the device under test operates under different simulated load conditions (i.e., different impedance points), different harmonics will be generated. Harmonics are frequency components that are integer multiples of the input signal frequency, and the harmonic values ​​corresponding to each impedance point can be obtained through the second vector signal analysis module. These harmonic values ​​reflect the nonlinear characteristics of the device under test under different load conditions. This embodiment finds the largest harmonic based on the harmonic value corresponding to each impedance point. The maximum harmonic value reflects the most unfavorable harmonic condition of the device under test under the current target mismatch level.

[0160] In summary, this embodiment can flexibly adjust the phase and amplitude of the signal by means of an adjustable phase vector signal source structure. In this way, it is possible to simulate many different impedance points on the Smith chart, with a wider impedance adjustment range. Compared with the traditional method, the present invention can more accurately set various complex load conditions, providing strong support for testing the performance of the device under test under different loads, thereby greatly improving the accuracy of impedance adjustment.

[0161] This embodiment records the signal values ​​of the vector signal source and the adjustable phase vector signal source at a specific connection point by removing the device under test before testing, providing an accurate reference for subsequent testing. At the same time, the second adjustable phase vector signal source and the third adjustable phase vector signal source are used to offset the second and third harmonics of the link, effectively removing the harmonic interference caused by the link, which not only improves the accuracy of the test, but also after the calibration is completed, the signal source can be directly adjusted according to the calibration results in subsequent tests, which greatly speeds up the test speed and improves the test efficiency.

[0162] This embodiment can comprehensively evaluate the performance of the device under test by obtaining harmonic information of the device under test under different mismatch degrees, especially determining the maximum harmonic, and simulate multiple impedance points on the Smith chart for testing to obtain the working status of the device under different load conditions, with a higher impedance adjustment range and accuracy and a faster adjustment speed.

[0163] In this embodiment, an active load traction device is also provided, which is used to implement the above embodiments and preferred implementations, and the descriptions that have been made will not be repeated. As used below, the term "module" can be a combination of software and / or hardware that implements a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

[0164] This embodiment provides an active load-pull device, which is applied to Figure 5 In a control module of an active load traction system shown in FIG. Fig.10 As shown, including:

[0165] The target mismatch degree acquisition module 1001 is used to acquire the target mismatch degree when testing the device under test in the test link, and calculate the reflection power coefficient according to the target mismatch degree; the target mismatch degree is used to indicate the target reflection ratio of the test signal during the transmission process;

[0166] The signal acquisition module 1002 to be sent is used to determine the target test signal value to be sent by the vector signal source in the test link and the target phase adjustable signal value to be sent by the first adjustable phase vector signal source according to the reflected power coefficient;

[0167] The impedance point determination module 1003 is used to determine a plurality of corresponding impedance points on the Smith chart according to the reflected power coefficient; each impedance point on the Smith chart is used to indicate a different load impedance condition;

[0168] A testing module 1004 is used to simulate multiple impedance points on the Smith chart by adjusting the amplitude and phase of the first adjustable phase vector signal source, and control the vector signal source to send the target test signal value, and control the first adjustable phase vector signal source to send the target phase adjustable signal value, so as to test the device under test;

[0169] The maximum harmonic acquisition module 1005 is used to acquire the harmonic value corresponding to each impedance point, and acquire the maximum harmonic of the device under test at the target mismatch level according to the harmonic value corresponding to each impedance point.

[0170] In an optional implementation, the device is further used to: before testing the device under test in the test link and under the condition that the device under test is removed from the test link, obtain a plurality of frequency points within the signal frequency range;

[0171] For each frequency point, the test signal value emitted by the vector signal source and the first received signal value corresponding to the specific connection point are recorded to construct a first calibration table, and the phase-adjustable signal value emitted by the first adjustable phase vector signal source and the second received signal value corresponding to the specific connection point are recorded to construct a second calibration table;

[0172] The second adjustable phase vector signal source is controlled to emit a secondary cancellation signal with a phase opposite to the second harmonic of the test link to cancel the second harmonic of the test link, and the third adjustable phase vector signal source is controlled to emit a third cancellation signal with a phase opposite to the third harmonic of the test link to cancel the third harmonic of the test link.

[0173] In an optional implementation, the signal to be sent acquisition module 1002 is further used for:

[0174] Determining, from the first calibration table, a target test signal value to be sent by a vector signal source in the test link according to the reflected power coefficient;

[0175] According to the reflected power coefficient, a target phase adjustable signal value to be emitted by the first adjustable phase vector signal source is determined from the second calibration table.

[0176] The further functional description of each of the above modules and units is the same as that of the above corresponding embodiments and will not be repeated here.

[0177] The embodiment of the present invention also provides a computer device, see Fig.11 , Fig.11 is a schematic diagram of the structure of a computer device provided by an optional embodiment of the present invention, such as Fig.11 As shown, the computer device includes: one or more processors 10, a memory 20, and interfaces for connecting various components, including high-speed interfaces and low-speed interfaces. Various components are connected to each other using different buses for communication, and can be installed on a common mainboard or installed in other ways as needed. The processor can process the instructions executed in the computer device, including instructions stored in or on the memory to display the graphical information of the GUI on an external input / output device (such as, a display device coupled to the interface). In some optional embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories and multiple memories. Similarly, multiple computer devices can be connected, and each device provides some necessary operations (for example, as a server array, a group of blade servers, or a multi-processor system). Fig.11A processor 10 is taken as an example.

[0178] The processor 10 may be a central processing unit, a network processor or a combination thereof. The processor 10 may further include a hardware chip. The hardware chip may be a dedicated integrated circuit, a programmable logic device or a combination thereof. The programmable logic device may be a complex programmable logic device, a field programmable gate array, a general purpose array logic or any combination thereof.

[0179] The memory 20 stores instructions executable by at least one processor 10, so that at least one processor 10 executes the method shown in the above embodiment.

[0180] The memory 20 may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function; the data storage area may store data created according to the use of the computer device, etc. In addition, the memory 20 may include a high-speed random access memory, and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some optional embodiments, the memory 20 may optionally include a memory remotely arranged relative to the processor 10, and these remote memories may be connected to the computer device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0181] The memory 20 may include a volatile memory, such as a random access memory; the memory may also include a non-volatile memory, such as a flash memory, a hard disk or a solid state drive; the memory 20 may also include a combination of the above types of memory.

[0182] The computer device further comprises a communication interface 30 for the computer device to communicate with other devices or a communication network.

[0183] The embodiment of the present invention also provides a computer-readable storage medium. The method according to the embodiment of the present invention can be implemented in hardware, firmware, or can be implemented as a computer code that can be recorded in a storage medium, or can be implemented as a computer code that is originally stored in a remote storage medium or a non-temporary machine-readable storage medium and will be stored in a local storage medium through a network download, so that the method described herein can be stored in such software processing on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only storage memory, a random access memory, a flash memory, a hard disk or a solid-state hard disk, etc.; further, the storage medium can also include a combination of the above types of memories. It can be understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component that can store or receive software or computer code. When the software or computer code is accessed and executed by a computer, a processor, or hardware, the method shown in the above embodiment is implemented.

[0184] A part of the present invention may be applied as a computer program product, such as a computer program instruction, which, when executed by a computer, can call or provide the method and / or technical solution according to the present invention through the operation of the computer. Those skilled in the art should understand that the existence of the computer program instruction in a computer-readable medium includes, but is not limited to, a source file, an executable file, an installation package file, etc., and accordingly, the way in which the computer program instruction is executed by the computer includes, but is not limited to: the computer directly executes the instruction, or the computer compiles the instruction and then executes the corresponding compiled program, or the computer reads and executes the instruction, or the computer reads and installs the instruction and then executes the corresponding installed program. Here, the computer-readable medium may be any available computer-readable storage medium or communication medium accessible to the computer.

[0185] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the defined scope.

Claims

1. A harmonic test link for a device under test, characterized in that: The test link comprises: an adjustable phase vector signal source structure, and a vector signal source, a device under test, a coupler and a vector signal analysis module connected in sequence; the output end of the adjustable phase vector signal source structure is connected to the first input end of the coupler; The adjustable phase vector signal source structure is used to send a phase adjustable signal to the vector signal source through the coupler to simulate different load conditions; The vector signal source is used to send a test signal to the device under test; the phase-adjustable signal has the same frequency parameters and local oscillator parameters as the test signal; The coupler is used to perform partial separation processing on the DUT signal output by the DUT, and output the result to the vector signal analysis module; The vector signal analysis module is used to receive and analyze the DUT signal emitted by the coupler to obtain harmonic information of the DUT; The adjustable phase vector signal source structure includes a first adjustable phase vector signal source, a second adjustable phase vector signal source and a third adjustable phase vector signal source; The output end of the first adjustable phase vector signal source, the output end of the second adjustable phase vector signal source and the output end of the third adjustable phase vector signal source are connected to the first input end of the coupler through a combiner; The first adjustable phase vector signal source is used to send a phase adjustable signal to the vector signal source to simulate different load conditions; The second adjustable phase vector signal source is used to send a secondary cancellation signal with a phase opposite to the second harmonic of the test link to cancel the second harmonic of the test link; The third adjustable phase vector signal source is used to send out a third-order cancellation signal with a phase opposite to the third harmonic of the test link to cancel the third harmonic of the test link.

2. The test link according to claim 1, characterized in that: The test link also includes a first amplifier and a first circulator; The output end of the vector signal source is connected to the second input end of the coupler through the first amplifier, the first circulator and the device under test in sequence; The first amplifier is used to amplify the test signal sent by the vector signal source; The first circulator is used to transmit the amplified test signal to the device under test in a unidirectional manner.

3. The test link according to claim 1, characterized in that: The test link also includes a second amplifier, a second circulator, a third amplifier, a third circulator, a fourth amplifier and a fourth circulator; The output end of the first adjustable phase vector signal source is connected to the first input end of the coupler through the second amplifier, the second circulator and the combiner in sequence; The output end of the second adjustable phase vector signal source is connected to the first input end of the coupler through the third amplifier, the third circulator and the combiner in sequence; The output end of the third adjustable phase vector signal source is connected to the first input end of the coupler through the fourth amplifier, the fourth circulator and the combiner in sequence; The second amplifier is used to amplify the phase-adjustable signal sent by the first adjustable phase vector signal source; the second circulator is used to unidirectionally transmit the amplified phase-adjustable signal to the combiner; The third amplifier is used to amplify the secondary cancellation signal emitted by the second adjustable phase vector signal source; the third circulator is used to unidirectionally transmit the amplified secondary cancellation signal to the combiner; The fourth amplifier is used to amplify the third-order cancellation signal emitted by the third adjustable phase vector signal source; the fourth circulator is used to unidirectionally transmit the amplified third-order cancellation signal to the combiner.

4. The test link according to claim 1, characterized in that: The vector signal analysis module includes a first vector signal analysis module and a second vector signal analysis module; The coupler is used to perform partial separation processing on the DUT signal output by the DUT to obtain separated harmonic signals and fundamental signals, and output the harmonic signals to the first vector signal analysis module, and output the fundamental signal to the second vector signal analysis module; The first vector signal analysis module is used to receive and analyze the harmonic signal emitted by the coupler to obtain harmonic information of the device under test; The second vector signal analysis module is used to receive and analyze the fundamental wave signal emitted by the coupler to obtain the signal transmission quality of the test link.

5. The test link according to claim 4, characterized in that: The test link also includes a duplexer and an attenuator; The output end of the coupler is connected to the input end of the duplexer, the first output end of the duplexer is connected to the input end of the first vector signal analysis module, and the second output end of the duplexer is connected to the input end of the second vector signal analysis module through the attenuator; The duplexer is used to transmit the harmonic signal to the first vector signal analysis module, and transmit the fundamental signal to the second vector signal analysis module through the attenuator; The attenuator is used to perform attenuation processing on the fundamental wave signal.

6. An active load-pull system, characterized in that: The system comprises a control module and a harmonic test link of a device under test as claimed in any one of claims 1 to 5; The control module is used for: When testing the device under test in the test link, a target mismatch degree is obtained, and a reflection power coefficient is calculated according to the target mismatch degree; the target mismatch degree is used to indicate a target reflection ratio of a test signal during transmission; Determining a test signal value of a vector signal source in the test link and a phase adjustable signal value of a first adjustable phase vector signal source according to the reflected power coefficient; According to the reflected power coefficient, a plurality of corresponding impedance points are determined on a Smith chart; each impedance point on the Smith chart is used to indicate a different load impedance condition; Simulating a plurality of impedance points on the Smith chart by adjusting the amplitude and phase of the first adjustable phase vector signal source, and controlling the vector signal source to send the test signal value, and controlling the first adjustable phase vector signal source to send the phase adjustable signal value, so as to test the device under test; The harmonic value corresponding to each impedance point is obtained, and according to the harmonic value corresponding to each impedance point, the maximum harmonic of the device under test at the target mismatch degree is obtained.

7. An active load-pull method, characterized in that: The method is applied to a control module of an active load traction system according to claim 6, and the method comprises: When testing the device under test in the test link, a target mismatch degree is obtained, and a reflection power coefficient is calculated according to the target mismatch degree; the target mismatch degree is used to indicate a target reflection ratio of a test signal during transmission; Determining, according to the reflected power coefficient, a target test signal value to be sent by the vector signal source in the test link and a target phase adjustable signal value to be sent by the first adjustable phase vector signal source; According to the reflected power coefficient, a plurality of corresponding impedance points are determined on a Smith chart; each impedance point on the Smith chart is used to indicate a different load impedance condition; Simulating a plurality of impedance points on the Smith chart by adjusting the amplitude and phase of the first adjustable phase vector signal source, and controlling the vector signal source to emit the target test signal value, and controlling the first adjustable phase vector signal source to emit the target phase adjustable signal value, so as to test the device under test; The harmonic value corresponding to each impedance point is obtained, and according to the harmonic value corresponding to each impedance point, the maximum harmonic of the device under test at the target mismatch degree is obtained.

8. The method according to claim 7, characterized in that Before testing the device under test in the test link, the method further includes: Under the condition that the device under test is removed from the test link, a plurality of frequency points within a signal frequency range are obtained; For each frequency point, the test signal value emitted by the vector signal source and the first received signal value corresponding to the specific connection point are recorded to construct a first calibration table, and the phase-adjustable signal value emitted by the first adjustable phase vector signal source and the second received signal value corresponding to the specific connection point are recorded to construct a second calibration table; The second adjustable phase vector signal source is controlled to emit a secondary cancellation signal with a phase opposite to the second harmonic of the test link to cancel the second harmonic of the test link, and the third adjustable phase vector signal source is controlled to emit a third cancellation signal with a phase opposite to the third harmonic of the test link to cancel the third harmonic of the test link.

9. The method according to claim 8, characterized in that The step of determining, according to the reflected power coefficient, a target test signal value to be sent by a vector signal source in the test link and a target phase adjustable signal value to be sent by a first adjustable phase vector signal source comprises: determining, from the first calibration table, a target test signal value to be sent by a vector signal source in the test link according to the reflected power coefficient; According to the reflected power coefficient, a target phase adjustable signal value to be emitted by the first adjustable phase vector signal source is determined from the second calibration table.

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