Impedance tuner, test system, and electronic device

Abstract

The application provides an impedance tuner, a test system and an electronic device. The impedance tuner comprises a bridge module, a first power division module, a second power division module, a first phase shift module and a second phase shift module. A plurality of power signals can be obtained based on a first power signal through the bridge module, the first power division module and the second power division module. Each power signal is phase shifted through the first phase shift module and the second phase shift module, so that impedance tuning of an input port of the bridge module can be realized. A fourth power signal output by an isolation port of the bridge module is detected, so that a mapping relationship between impedance and power, efficiency, gain and error vector magnitude can be obtained without using an additional multi-port device.

Description

Technical Field

[0001] This application belongs to the field of impedance tuner technology, and particularly relates to an impedance tuner, a test system, and electronic equipment. Background Technology

[0002] An electrically adjustable impedance tuner is a radio frequency (RF) or microwave device that can quickly and accurately change its input or output impedance through electrical signal control. It is commonly used for RF device testing and characterization, such as load pull testing and source pull testing.

[0003] Electrically adjustable impedance tuners typically have only one external port, which means they need to be used with additional multi-port devices (such as couplers) to obtain the mapping relationship between the impedance of the device under test and its power, efficiency, gain, and error vector magnitude. Furthermore, they require high performance parameters from the multi-port devices. Utility Model Content

[0004] The purpose of this application is to provide an impedance tuner, a testing system, and an electronic device, which aims to solve the problem that traditional electrically adjustable impedance tuners require additional devices for testing during use.

[0005] A first aspect of this application provides an impedance tuner, comprising: a bridge module, the input port of which is used to receive a first power signal; a first power divider module, the input terminal of which is connected to a first output port of the bridge module; a second power divider module, the input terminal of which is connected to a second output port of the bridge module; a first phase shifter module, the two ends of which are respectively connected to the two output terminals of the first power divider module; and a second phase shifter module, the two ends of which are respectively connected to the two output terminals of the second power divider module. The bridge module is used to output a second power signal and a third power signal based on the first power signal through the first output port and the second output port, respectively. The bridge module is also used to output a fourth power signal based on the signals received by the first output port and the second output port through the isolation port of the bridge module.

[0006] In one embodiment, the bridge module includes a 90° bridge, the amplitude of the second power signal is the same as the amplitude of the third power signal, and the phase difference between the second power signal and the third power signal is 90°.

[0007] In one embodiment, both the first phase shifting module and the second phase shifting module include a phase shifter.

[0008] In one embodiment, the impedance tuner further includes a control module connected to the first phase shift module and the second phase shift module, which is used to configure the phase shift amount of the first phase shift module and the second phase shift module.

[0009] In one embodiment, the control module includes a DIP switch and / or a control chip.

[0010] In one embodiment, both the first power divider module and the second power divider module include a 1-to-2 power divider.

[0011] In one embodiment, the impedance tuner further includes a pre-matching circuit connected to the input port and isolation port of the bridge module.

[0012] In one embodiment, the pre-matching circuit includes a π-shaped matching circuit.

[0013] A second aspect of this application provides a test system including the impedance tuner described above.

[0014] A third aspect of this application provides an electronic device including the impedance tuner described above.

[0015] The beneficial effects of this application embodiment compared with the prior art are as follows: Multiple power signals can be obtained based on a first power signal through the bridge module, the first power divider module, and the second power divider module. By shifting the phases of each power signal through the first and second phase-shifting modules, impedance tuning of the input port of the bridge module can be achieved. By detecting the fourth power signal output from the isolation port of the bridge module, the mapping relationship between impedance and power, efficiency, gain, and error vector amplitude can be obtained without using additional multi-port devices. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the structure of an impedance tuner provided in one embodiment of this application; Figure 2 A schematic diagram of the specific structure of an impedance tuner provided in an embodiment of this application; Figure 3 A simulation circuit diagram of an impedance tuner provided in an embodiment of this application; Figure 4aA schematic diagram of the tuning range of the impedance tuner when the value range of Phase1 is 0°~360° and Phase2 is 0, provided for an embodiment of this application; Figure 4b A schematic diagram showing the insertion loss range of the impedance tuner when Phase 1 is in the range of 0° to 360° and Phase 2 is 0, provided as an embodiment of this application. Figure 5a A schematic diagram of the tuning range of the impedance tuner when the value range of Phase 1 is 0°~360° and the value range of Phase 2 is 0°~90° is provided for an embodiment of this application. Figure 5b A schematic diagram showing the insertion loss range of the impedance tuner when the value range of Phase 1 is 0°~360° and the value range of Phase 2 is 0°~90°, provided as an embodiment of this application. Figure 6a A schematic diagram of the tuning range of the impedance tuner provided in an embodiment of this application, when the value range of Phase 1 is 0°~360°, the value range of Phase 2 is 0°~90°, and the link loss is 7dB. Figure 6b This is a schematic diagram illustrating the insertion loss range of the impedance tuner when the value range of Phase 1 is 0°~360°, the value range of Phase 2 is 0°~90°, and the link loss is 7dB, according to an embodiment of this application. Figure 7a An impedance point distribution diagram provided in an embodiment of this application when phase2 = 45° and phase1 ∈ [0°, 360°]; Figure 7b An impedance point distribution diagram provided in an embodiment of this application when phase2=90° and phase1∈[0°, 360°]; Figure 7c An impedance point distribution diagram provided in an embodiment of this application when phase2 = 180° and phase1 ∈ [0°, 360°]; Figure 8a An impedance point distribution diagram provided in an embodiment of this application when phase1=0° and phase2∈[0°, 360°]; Figure 8b An impedance point distribution diagram provided for an embodiment of this application when phase1 = 90° and phase2 ∈ [0°, 360°]; Figure 8c An impedance point distribution diagram provided in an embodiment of this application when phase1 = 180° and phase2 ∈ [0°, 360°]; Figure 9A schematic diagram of the PCB circuit of an impedance tuner provided in one embodiment of this application; Figure 10 This is a schematic diagram of the structure of a test system provided in one embodiment of this application; Figure 11 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0018] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0019] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0020] Electrically adjustable impedance tuners typically have only one external port, requiring them to be used with a coupler or power divider to obtain the mapping relationship between the impedance, power, efficiency, gain, and error vector amplitude of the device under test (DUT). Some electrically adjustable impedance tuners also obtain the required electrical parameters by adding output channels of a power divider; however, simply adding output channels of a power divider may result in the inability to collect all reflected energy, leading to a limited tuning range.

[0021] Figure 1 A schematic diagram of an impedance tuner according to an embodiment of this application is shown. For ease of explanation, only the parts relevant to this embodiment are shown, and are described in detail below: An impedance tuner 10 includes: a bridge module 100, a first power divider module 200, a second power divider module 300, a first phase shifter module 400, and a second phase shifter module 500.

[0022] The input port in of the bridge module 100 is used to receive the first power signal; the input terminal of the first power divider module 200 is connected to the first output port out1 of the bridge module 100; the input terminal of the second power divider module 300 is connected to the second output port out2 of the bridge module 100; the two ends of the first phase shifter module 400 are respectively connected to the two output terminals of the first power divider module 200; the two ends of the second phase shifter module 500 are respectively connected to the two output terminals of the second power divider module 300; the bridge module 100 is used to output a second power signal and a third power signal respectively through the first output port out1 and the second output port out2 based on the first power signal; the bridge module 100 is also used to output a fourth power signal through the isolation port iso of the bridge module 100 based on the signals received by the first output port out1 and the second output port out2.

[0023] Multiple power signals can be obtained based on the first power signal through the bridge module 100, the first power divider module 200 and the second power divider module 300. By shifting the phase of each power signal through the first phase shifter module 400 and the second phase shifter module 500, the impedance of the input port in of the bridge module 100 can be tuned.

[0024] By detecting the fourth power signal output from the isolator port of the bridge module 100, the complete reflected energy can be collected without using additional multi-port devices, and the mapping relationship between impedance and power, efficiency, gain, and error vector magnitude can be obtained.

[0025] In one embodiment, when performing load pull test, the input port in of the bridge module 100 of this application embodiment can be connected to the RF output terminal of the DUT (Device Under Test), and the isolation port iso of the bridge module 100 can be directly connected to devices such as wireless test instrument, power meter, and digital multimeter. The load pull heat map of impedance, power, efficiency, gain, and error vector amplitude can be output without the need for an additional coupler, which simplifies the test topology.

[0026] In one embodiment, such as Figure 2 As shown, the bridge module 100 includes a 90° bridge 101, the amplitude of the second power signal is the same as the amplitude of the third power signal, and the phase difference between the second power signal and the third power signal is 90°.

[0027] It should be noted that, in addition to generating a second power signal and a third power signal based on the first power signal and outputting the second power signal and the third power signal respectively through the two output terminals of the 90° bridge 101, when the two output terminals of the 90° bridge 101 receive the input power signal, a fourth power signal can also be output through the isolation terminal of the 90° bridge 101.

[0028] For example, in one embodiment, the third power signal output by the 90° bridge 101 lags behind the second power signal by 90°.

[0029] In some embodiments, the bridge module 100 may use other types of bridges instead of the 90° bridge 101, for example, a 180° bridge may be used instead of the 90° bridge 101. It is understood that, accordingly, after replacing the bridges, the phase shift amounts of the first phase shift module 400 and the second phase shift module 500 need to be adaptively set according to the degree of the bridges.

[0030] In one embodiment, such as Figure 2 As shown, both the first phase shifting module 400 and the second phase shifting module 500 include a phase shifter.

[0031] For example, in one embodiment, the first phase shifting module 400 includes a first phase shifter 401, and the second phase shifting module 500 includes a second phase shifter 501.

[0032] It should be noted that since multiple signals output by the same power divider module usually have the same amplitude and phase, when the same signal is connected to both ends of the phase shifter, there is no current at the center end face of the first phase shifter 401 and the second phase shifter 501. The first phase shifter 401 and the second phase shifter 501 are equivalent to an open circuit state, and the signal output by the power divider module is phase-shifted and reflected.

[0033] By using the first power divider module 200 and the second power divider module 300 in conjunction with the first phase shifter module 400 and the second phase shifter module 500, the impedance tuner 10 can be enhanced to resist link loss, thereby expanding the impedance tuning range.

[0034] In one embodiment, the impedance tuner 10 further includes a control module connected to the first phase shift module 400 and the second phase shift module 500, for configuring the phase shift amount of the first phase shift module 400 and the second phase shift module 500.

[0035] It should be noted that by configuring the phase shift amounts of the first phase shift module 400 and the second phase shift module 500 through the control module, the tuning range of the impedance tuner 10 can be adjusted. Simultaneously, since there is a phase difference between the second power signal and the third power signal output by the bridge module 100, the phase shift amounts of the first phase shift module 400 and the second phase shift module 500 also need to be configured according to the phase of the second power signal and the third power signal to reduce the insertion loss of the impedance tuner 10.

[0036] For example, if the third power signal lags behind the second power signal, the phase shift amount of the second phase shift module 500 needs to be greater than that of the first phase shift module 400.

[0037] For example, when the third power signal lags behind the second power signal, and the second power signal and the third power signal are 90° out of phase (i.e., the bridge module 100 uses a 90° bridge 101), the phase shift of the second phase shift module 500 is 0° to 90° greater than the phase shift of the first phase shift module 400. In one embodiment, the phase shift of the first phase shift module 400 ranges from 0° to 360°, and the phase shift of the second phase shift module 500 ranges from 0° to 450°.

[0038] In one embodiment, the control module includes a DIP switch and / or a control chip.

[0039] It is understandable that the phase shift amounts of the first phase shift module 400 and the second phase shift module 500 can be manually configured via a DIP switch. The control chip, on the other hand, enables automatic and remote configuration of the phase shift amounts of the first phase shift module 400 and the second phase shift module 500. Compared to a mechanical tuner, the control module in this embodiment offers advantages such as faster tuning speed, higher tuning accuracy, lower cost, smaller size, and simpler structure.

[0040] In one embodiment, such as Figure 2 As shown, both the first power splitting module 200 and the second power splitting module 300 include a one-to-two power splitter.

[0041] A 1-to-2 power divider can generate and output two equal-amplitude, in-phase signals based on the received power signal, which are then provided to the corresponding phase-shifting modules.

[0042] Specifically, in one embodiment, the first power splitting module 200 may include a first one-to-two power splitter 201, and the second power splitting module 300 may include a second one-to-two power splitter 301.

[0043] It should be noted that the impedance tuner 10 in this embodiment can be simulated and analyzed at the circuit level using Advanced Design System (ADS) software. The corresponding circuit simulation schematic is shown below. Figure 3 As shown. Bridge module 100 can be constructed using Hybrid90, first power divider module 200 and second power divider module 300 can be constructed using PwrSplit2, first phase shifter module 400 and second phase shifter module 500 can be constructed using PhaseShiftSML, the losses of the phase shifter modules are constructed using ATTEN2 and ATTEN3, the phase shift amount of the first phase shifter module 400 is Phase1, and the phase shift amount of the second phase shifter module 500 is Phase1+Phase2.

[0044] In the case that the first phase shifting module 400 and the second phase shifting module 500 are lossless, such as Figure 4a , Figure 4bAs shown, when Phase 1 ranges from 0° to 360° and Phase 2 is 0, the tuning range of the impedance tuner 10 can cover the entire Smith chart; however, the insertion loss varies too much. Figure 5a , Figure 5b As shown, when Phase 1 ranges from 0° to 360° and Phase 2 ranges from 0° to 90°, the insertion loss of the impedance tuner 10 varies by 3dB, with a maximum insertion loss of 3dB, sacrificing some impedance tuning range. Considering the insertion loss present in actual board-level samples, when all the losses of the entire link are added to the phase-shifting module, such as... Figure 6a , Figure 6b As shown, with a link loss of 7dB, the tuning range of the impedance tuner 10 can still cover the Smith chart with VSWR≤2, at which point the insertion loss is 7~10dB. Based on the above circuit-level simulation analysis, it can be seen that the impedance tuner 10 of this embodiment has good tuning capability and insertion loss suppression capability, with a large tuning range and a small variation range and absolute value of insertion loss.

[0045] It should be noted that, based on Figure 3 When the circuit shown is simulated, if the phase shift of Phase 2 remains constant, and the phase shift of Phase 1 is iterated, the impedance point will rotate along the reflection coefficient circle on the Smith chart. At this time, the amplitude of the impedance point remains unchanged, but the phase changes. Figure 7a , Figure 7b and Figure 7c The impedance point distribution diagrams are shown for phase 2 = 45° and phase 1 ∈ [0°, 360°], phase 2 = 90° and phase 1 ∈ [0°, 360°], and phase 2 = 180° and phase 1 ∈ [0°, 360°], respectively. If the phase shift of Phase 1 is fixed, and the phase shift of Phase 2 is iterated, the impedance point will rotate along a circle with the diameter of the line connecting the center of the Smith chart to any point on its edge. At this time, the amplitude and phase of the impedance point will change. Figure 8a , Figure 8b and Figure 8cImpedance point distribution diagrams are shown for phase 1 = 0° and phase 2 ∈ [0°, 360°], phase 1 = 90° and phase 2 ∈ [0°, 360°], and phase 1 = 180° and phase 2 ∈ [0°, 360°], respectively. Simulation results obtained by traversing Phase 1 and Phase 2 show that when the bridge module 100 uses a 90° bridge 101, and the value range of Phase 2 is 0°~90°, the impedance tuner 10 exhibits good tuning capability and insertion loss suppression capability. Therefore, in this embodiment, the value range of Phase 2 is 0°~90°.

[0046] In one embodiment, such as Figure 9 As shown, the impedance tuner 10 also includes a pre-matching circuit 600, which is connected to the input port in and the isolation port iso of the bridge module 100.

[0047] Understandably, the pre-matching circuit 600 can configure the impedance of the input port in and the isolation port iso of the bridge module 100 according to actual needs, thereby configuring the input impedance and output impedance of the impedance tuner 10.

[0048] In one embodiment, the pre-matching circuit 600 includes a π-shaped matching circuit.

[0049] Specifically, a π-shaped matching circuit can be constructed using capacitors and other devices according to actual needs to adjust the tuning range of the impedance tuner 10, which is beneficial for testing the load pull of some DUT devices with low output impedance.

[0050] For example, in one embodiment, the bridge module 100 is implemented by a branch-line directional coupler in the form of a coplanar waveguide; the first power divider module 200 and the second power divider module 300 are respectively implemented by a 1-to-2 Wilkinson power divider in the form of a coplanar waveguide; and the first phase shifter module 400 and the second phase shifter module 500 are respectively implemented by a 6-phase digital phase shifter chip with a phase shift step of 5.6°. In some embodiments, the impedance tuner 10 also includes a power supply module, a mechanical DIP switch module, and a CNC pin header module, etc., which will not be described in detail in this embodiment.

[0051] Figure 10 A schematic diagram of the structure of a test system provided in an embodiment of this application is shown. For ease of explanation, only the parts relevant to this embodiment are shown, and are described in detail below: A test system 20 includes an impedance tuner 10 as described in any of the above embodiments. The test system 20 can use the impedance tuner 10 to test radio frequency devices and microwave devices.

[0052] In one embodiment, the test system 20 includes a signal analysis module 30, which is connected to the input port in of the bridge module 100 of the impedance tuner 10. The signal analysis module 30 is used to obtain the mapping relationship between impedance and power, efficiency, gain, and error vector amplitude based on the fourth power signal output from the input port in of the bridge module 100. The signal analysis module 30 may include devices such as a wireless comprehensive tester, a power meter, and a digital multimeter.

[0053] Figure 11 A schematic diagram of the structure of an electronic device according to an embodiment of this application is shown. For ease of explanation, only the parts related to this embodiment are shown, and the details are as follows: An electronic device 40 includes an impedance tuner 10 as described in any of the above embodiments.

[0054] It is understandable that the electronic device 40 can obtain multiple power signals based on the first power signal through the bridge module 100, the first power divider module 200, and the second power divider module 300 of the impedance tuner 10. By shifting the phases of each power signal through the first phase shifter module 400 and the second phase shifter module 500, the impedance tuning of the input port in of the bridge module 100 can be achieved. By detecting the fourth power signal output from the isolation port iso of the bridge module 100, the mapping relationship between impedance and power, efficiency, gain, and error vector magnitude can be obtained without using additional multi-port devices.

[0055] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0056] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0057] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. An impedance tuner, characterized in that, include: A bridge module, wherein the input port of the bridge module is used to receive a first power signal; The first power divider module has its input terminal connected to the first output port of the bridge module; The second power divider module has its input terminal connected to the second output port of the bridge module. The first phase shifting module has its two ends connected to the two output terminals of the first power divider module, respectively. The second phase shifting module has its two ends connected to the two output terminals of the second power divider module, respectively. The bridge module is used to output a second power signal and a third power signal respectively through the first output port and the second output port based on the first power signal. The bridge module is also used to output a fourth power signal through the isolation port of the bridge module based on the signals received by the first output port and the second output port.

2. The impedance tuner as described in claim 1, characterized in that, The bridge module includes a 90° bridge, the amplitude of the second power signal is the same as the amplitude of the third power signal, and the phase difference between the second power signal and the third power signal is 90°.

3. The impedance tuner as described in claim 1, characterized in that, Both the first phase shifting module and the second phase shifting module include a phase shifter.

4. The impedance tuner as described in claim 3, characterized in that, The impedance tuner also includes a control module, which is connected to the first phase shift module and the second phase shift module and is used to configure the phase shift amount of the first phase shift module and the second phase shift module.

5. The impedance tuner as described in claim 4, characterized in that, The control module includes a DIP switch and / or a control chip.

6. The impedance tuner as described in any one of claims 1 to 5, characterized in that, Both the first power divider module and the second power divider module include a 1-to-2 power divider.

7. The impedance tuner as described in any one of claims 1 to 5, characterized in that, The impedance tuner also includes a pre-matching circuit, which is connected to the input port and isolation port of the bridge module.

8. The impedance tuner as described in claim 7, characterized in that, The pre-matching circuit includes a π-shaped matching circuit.

9. A testing system, characterized in that, Includes the impedance tuner as described in any one of claims 1 to 8.

10. An electronic device, characterized in that, Includes the impedance tuner as described in any one of claims 1 to 8.

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