System and method for testing the impact of strong microwave electric fields on amplifier chip performance

Abstract

The present invention aims to provide a system and method for testing the impact of strong microwave electric fields on amplifier chip performance, belonging to the field of microwave and millimeter wave testing technology. This testing system innovatively utilizes a reentrant resonant cavity to test the impact of strong microwave electric fields on amplifier chip performance. This system enables testing of amplifier performance changes under strong electric field strengths. While maintaining the same microwave injection power level, it effectively expands the range of electric field strengths that can be used for testing, improving the efficiency of establishing a strong microwave electric field environment and reducing research costs.

Description

Technical Field

[0001] The present invention belongs to the technical field of microwave and millimeter wave testing, and in particular relates to a system and method for testing the level of influence of a strong microwave electric field on the performance of an amplifier chip. Background Art

[0002] Whether in the military or civilian sectors, electronic and communication systems are essential components. Furthermore, as electronic device manufacturing processes become smaller and their integration levels continue to increase, system functionality and integration are becoming increasingly complex. Furthermore, with the increasing use of electromagnetic waves in our daily lives and the increasing number of electronic and communication devices, electromagnetic radiation and microwave interference are becoming increasingly prevalent. However, electromagnetic interference can cause performance changes in devices, and in severe cases, even damage them. Therefore, the performance changes of systems exposed to microwave electric fields are of great research significance. On the one hand, complex electromagnetic environments place higher demands on the electromagnetic protection of equipment. On the other hand, as the operating frequency and power of communication equipment and other devices increase, devices are more susceptible to electromagnetic interference.

[0003] For electronic or communication equipment, the receiver is the most important coupling device in front-door coupling, and the amplifier is a key component within the receiver. Testing the level of change in the impact of strong microwave electric fields on the performance of amplifier chips can provide certain data references for the electromagnetic protection of important communication equipment. The performance changes of equipment or devices under microwave electric fields are usually evaluated using injection and irradiation methods. The former directly injects the interference signal into the device under test. The advantages of this method are simple experimental conditions and steps, and the power used in the experiment is relatively low. However, since the energy entry method is different from actual irradiation, the device's anti-interference ability cannot be accurately evaluated. The latter can more realistically simulate the situation of electronic equipment being irradiated by microwave electric fields, which is closer to the actual situation. However, this method usually requires a high-power microwave source to generate a sufficiently strong electric field strength.

[0004] Ding Changqi of the University of Electronic Science and Technology of China (Ding Changqi. Immunity Test System Based on TEM Chamber [D]. University of Electronic Science and Technology of China, 2020) conducted some research using a TEM chamber. This involved selecting a power amplifier as the chip under test, varying the input power of the TEM chamber to change the electric field strength, and measuring the input and output power of the chip under test to analyze the impact of strong microwave electric fields on the performance of the amplifier chip. However, due to the structure and principle of the TEM chamber, this method produces a relatively low microwave electric field strength. Achieving a strong microwave electric field also requires a high-power microwave source to drive the TEM chamber, which increases research costs and reduces research efficiency. Fang Jinyong created a strong electric field environment in a dark room through antenna radiation to test the impact level on the device (Fang Jinyong, Liu Guozhi, Li Ping et al. Experimental study on high-power microwave pulse width effect [J]. High Power Laser and Particle Beams, 1999(05):639-642.) to more realistically simulate the situation of electronic equipment being irradiated by microwave electric fields, that is, to achieve the simulation of strong microwave electric fields, but the cost is high and the calibration of the field strength is difficult. Summary of the Invention

[0005] To address the existing problem of irradiation methods being unable to efficiently and cost-effectively construct a strong microwave electric field, the present invention aims to provide a system and method for testing the impact of strong microwave electric fields on amplifier chip performance. This testing system innovatively utilizes a reentrant resonant cavity to test the impact of strong microwave electric fields on amplifier chip performance. This system enables testing of amplifier performance changes under strong electric field intensities. While maintaining the same microwave injection power level, it effectively expands the range of electric field intensities that can be used for testing, improving the efficiency of constructing a strong microwave electric field environment and reducing research costs.

[0006] To achieve the above object, the technical solution of the present invention is as follows:

[0007] A test system for the level of influence of a strong microwave electric field on the performance of an amplifier chip includes a reentrant resonant cavity main cavity 1, a reentrant resonant cavity upper cover 2, a microwave electric probe 4, a first power meter 5, a second power meter 6, a first signal source 7, a second signal source 8, a power supply 9, a power amplifier 10, and a directional coupler 11;

[0008] The first signal source 7 is connected to one port of the power amplifier 10, and the other port of the power amplifier 10 is connected to the incident end of the directional coupler 11; the through end of the directional coupler 11 is connected to the microwave electric probe 4, the coupling end of the directional coupler 11 is connected to the first power meter 5, and the reflection end of the directional coupler 11 is connected to the matching load; the microwave electric probe 4 is arranged in the main cavity 1 of the reentrant resonant cavity at a distance not exceeding one-third of the cavity length from the bottom;

[0009] A cylindrical protrusion is provided at the center of the reentrant resonant cavity upper cover 2, and the chip to be tested 3 is fixedly provided on the protrusion. The power pin of the chip to be tested 3 passes through the reentrant resonant cavity upper cover 2 and is connected to the power supply 9, the input pin passes through the reentrant resonant cavity upper cover 2 and is connected to the second signal source 8, and the output pin passes through the reentrant resonant cavity upper cover 2 and is connected to the second power meter 6;

[0010] The main cavity 1 of the reentrant resonant cavity is composed of a cylindrical outer conductor with a hollow interior and an inner conductor arranged concentrically with the outer conductor. The lower end surface of the inner conductor is fixedly connected to the lower bottom surface of the outer conductor. A through hole is set in the center of the upper top surface of the outer conductor. The diameter of the through hole is the same as the size of the cylindrical protrusion of the upper cover plate 2 of the reentrant resonant cavity, and the height of the through hole is the same as the height of the cylindrical protrusion of the upper cover plate 2 of the reentrant resonant cavity, so that the upper cover plate 2 of the reentrant resonant cavity is completely matched with the upper top surface of the main cavity 1 of the reentrant resonant cavity, and the upper end surface of the inner conductor does not contact the chip 3 to be tested.

[0011] Furthermore, by adjusting the length of the microwave electric probe 4 penetrating into the main cavity 1 of the reentrant resonant cavity, the degree of coupling matching between the microwave electric probe and the reentrant resonant cavity can be achieved.

[0012] Furthermore, the chip to be tested 3 is fixed to the cylindrical protrusion of the reentrant resonant cavity upper cover 2 by screws. When the reentrant resonant cavity upper cover 2 completely overlaps with the top surface of the reentrant resonant cavity main cavity 1, the chip to be tested 3 is located at a place where the microwave electric field is evenly distributed in the reentrant resonant cavity main cavity 1.

[0013] Furthermore, the working mode of the reentrant resonant cavity main cavity 1 is TEM 00n mode, where n represents the nth mode.

[0014] Furthermore, the inner conductor height l is related to the electromagnetic wave resonance wavelength λ r The relationship is: l = (2n-1)λ r / 4.

[0015] Furthermore, the diameter r of the inner conductor is greater than or equal to 1.5 times the width of the chip to be tested; and the distance d between the upper end surface of the inner conductor and the top surface of the outer conductor is greater than or equal to 3 times the thickness of the chip to be tested.

[0016] The present invention also provides a method for performing a test based on the above-mentioned test system, comprising the following steps:

[0017] Step 1. Turn off the first signal source and use the second signal source to read the input power P of the chip under test when there is no microwave electric field. in1 , and use the second power meter to measure the output power P of the chip under test out1 ;

[0018] Step 2. Turn on the first signal source to excite the microwave electric field in the reentrant resonant cavity main cavity 1, adjust the power amplifier to the required microwave electric field intensity point, and use the second signal source and the second power meter to read the input power P in2 and measure the output power P out2 ;

[0019] Step 3. Based on the input power P of the chip under test obtained in steps 1 and 2 in1 、P in2 and output power P out1 、P out2 , calculate the performance parameters gain G and efficiency η respectively. The specific calculation process is as follows:

[0020]

[0021] Among them, U s is the power supply voltage, I d is the drain current;

[0022] Step 4. Compare the gain G and efficiency η with and without the microwave electric field to analyze the impact of the strong microwave electric field on the performance of the amplifier chip.

[0023] Furthermore, in step 2, the microwave electric field intensity is changed by adjusting the power input into the reentrant resonant cavity. The relationship between the microwave electric field intensity and the input power is as follows: the excitation signal frequency is adjusted so that the reentrant resonant cavity works at TEM 00n Mode, using the mode matching method to partition the mode and assume the field distribution in different areas, the mode coefficient is obtained according to the boundary conditions, and the field distribution in different areas can be obtained by calculation using the mode coefficient;

[0024] For any region, if only the conduction loss caused by the cavity wall is considered in the reentrant resonant cavity, the cavity loss P c for:

[0025]

[0026] Among them, R s is the surface resistivity, is the magnetic field intensity in the φ direction, wall represents the total area, and s is the area. Since the electromagnetic field distribution in each partition is different, the conductivity loss of each region is calculated according to the different positions of the reentrant resonant cavity wall and the different regions of the electromagnetic field, and the cavity loss P is obtained by summing them up. c总 ;

[0027] The total energy storage formula of the resonant cavity in each region of the electromagnetic field is:

[0028]

[0029] Where V is the volume of the reentrant cavity, W is the total energy storage in the cavity, and W e is the electric field energy storage, ε r is the relative dielectric constant, ε0 is the vacuum dielectric constant, is the electric field strength;

[0030] Similarly, by calculating the energy storage in different regions, the total energy storage of the resonant cavity W can be obtained by summing up. total ;

[0031] At this time, the resonant cavity quality factor Q c Easy to find:

[0032]

[0033] Where ω0 is the resonant angular frequency;

[0034] Assume that the microwave power TEM of the excitation cavity is 00n All is injected into the resonant cavity, and only the cavity loss P is considered c , by the quality factor Q c The electric field strength in the area where the chip to be tested is located can be expressed as follows:

[0035]

[0036] The mechanism of the present invention is as follows: The present invention innovatively uses a reentrant resonant cavity to test the level of impact of strong microwave electric fields on amplifier chip performance. A power amplifier is used to initially amplify a low-power signal source, and a microwave electrical probe is used to inject energy into the reentrant resonant cavity. The reentrant resonant cavity is then used to provide a uniform electric field acting on the chip under test. The level of impact of strong microwave electric fields on the amplifier chip performance is then tested using two power meters: one power meter monitors the electric field intensity in the reentrant resonant cavity's test area, and the other measures the output power of the chip under test. Furthermore, by varying the input power of the reentrant resonant cavity to control the electric field intensity, the amplifier's performance changes under different electric field intensities can be tested. Because the reentrant coaxial resonant cavity effectively compresses the electric field at the gap, a larger electric field intensity can be achieved at the gap when coupled with a lower power level. This effectively expands the range of electric field intensities that can be used for testing when the same power level is injected, improving the efficiency of constructing a strong microwave electric field environment and reducing research costs.

[0037] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0038] The test system for the level of influence of strong microwave electric fields on amplifier chip performance designed by the present invention effectively expands the range of electric field strength that can be used in the test when the same power level is injected. It has the characteristics of high test accuracy, good test stability, simple operation, and low use and maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is a schematic diagram of the overall structure of the system for testing the impact of strong microwave electric fields on amplifier chip performance according to the present invention.

[0040] Figure 2 It is a schematic structural diagram of the re-entrant resonant cavity in the test system of the influence of strong microwave electric field on the performance of amplifier chip of the present invention.

[0041] Figure 3 This is a schematic diagram of the re-entrant resonant cavity upper cover and the chip to be tested in the test system for the level of influence of strong microwave electric field on amplifier chip performance of the present invention.

[0042] Figure 4 This is a pattern partition diagram using the pattern matching method.

[0043] In the figure, 1 is the main cavity of the reentrant resonant cavity, 2 is the upper cover of the reentrant resonant cavity, 3 is the chip to be tested, 4 is the microwave electrical probe, 5 is the first power meter, 6 is the second power meter, 7 is the first signal source, 8 is the second signal source, 9 is the power supply, 10 is the power amplifier, and 11 is the directional coupler. DETAILED DESCRIPTION

[0044] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below in conjunction with the implementation methods and drawings.

[0045] The system for testing the impact of strong microwave electric fields on the performance of amplifier chips is shown in the figure below. Figure 1 As shown, it includes a reentrant resonant cavity main cavity 1, a reentrant resonant cavity upper cover 2, a microwave electrical probe 4, a first power meter 5, a second power meter 6, a first signal source 7, a second signal source 8, a power supply 9, a power amplifier 10 and a directional coupler 11.

[0046] The structural diagram of the reentrant resonant cavity main cavity 1 is as follows Figure 2 As shown, it consists of a hollow cylindrical outer conductor and an inner conductor arranged concentrically with the outer conductor. The lower end surface of the inner conductor is fixedly connected to the lower bottom surface of the outer conductor, and the upper end surface of the inner conductor does not contact the upper top surface of the outer conductor. A through hole is provided at the center of the upper top surface of the outer conductor. The diameter of the through hole is the same as the size of the cylindrical protrusion of the re-entrant resonant cavity upper cover plate 2, and the height of the through hole is the same as the height of the cylindrical protrusion of the re-entrant resonant cavity upper cover plate 2. This ensures that the re-entrant resonant cavity upper cover plate 2 is completely matched with the upper top surface of the re-entrant resonant cavity main cavity 1, and the chip to be tested 3 does not contact the upper end surface of the inner conductor.

[0047] The structural diagram of the reentrant resonant cavity upper cover 2 is as follows: Figure 3As shown, a cylindrical protrusion is provided at the center, and the chip to be tested 3 is fixed on the protrusion by screws. The power pin of the chip to be tested 3 is connected to the power supply 9, the input pin is connected to the second signal source 8, and the output pin is connected to the second power meter 6. The pins of the chip to be tested 3 are all connected to the outside through the through holes on the upper cover plate 2 of the reentrant resonant cavity.

[0048] The first signal source 7 is connected to one port of the power amplifier 10, and the other port of the power amplifier 10 is connected to the incident end of the directional coupler 11; the through end of the directional coupler 11 is connected to the microwave electric probe 4, the coupling end of the directional coupler 11 is connected to the first power meter 5, and the reflection end of the directional coupler 11 is connected to the matching load (not shown in the figure); the microwave electric probe 4 is arranged in the main cavity 1 of the reentrant resonant cavity near the lower bottom surface, preferably at one-third of the cavity length from the lower bottom surface.

[0049] Example 1

[0050] A method for testing the impact of a strong microwave electric field on the performance of an amplifier chip comprises the following steps:

[0051] Step 1. Place the chip under test in the reentrant resonant cavity main cavity 1, turn off the first signal source, that is, in the absence of microwave electric field, use the second signal source 8 to read the input power P of the chip under test. in1 , and use the second power meter 6 to measure the output power P of the chip under test out1 ;

[0052] Step 2: Keep the chip under test 3 in the reentrant resonant cavity main cavity 1 unchanged, turn on the first signal source 7, that is, the microwave electric field is present, adjust the power amplifier 10 to the required microwave electric field intensity point, use the second signal source 8 and the second power meter 6 to read the input power P in2 and measure the output power P out2 ;

[0053] The microwave electric field intensity in step 2 is changed by adjusting the power input into the reentrant resonant cavity. The relationship between the microwave electric field intensity and the input power is as follows: the excitation signal frequency is adjusted so that the reentrant resonant cavity works at TEM. 003 Pattern, pattern matching method is used for pattern partitioning, the specific partition diagram is as follows Figure 4 As shown, the reentrant resonant cavity of the present invention can be divided into two regions, and the field distributions in different regions are written out. The mode coefficients are obtained according to the boundary conditions, and the field distributions in different regions can be obtained by calculating the mode coefficients.

[0054] For the first partition (region 1), if only the conduction loss caused by the cavity wall is considered in the reentrant resonant cavity, the cavity loss is:

[0055]

[0056] The calculation of region 2 is similar to that of region 1. Therefore, the conductivity loss P is calculated based on the different positions of the reentrant cavity wall and the different regions of the electromagnetic field. c总 .

[0057] According to the resonant cavity energy storage formula:

[0058]

[0059] Where V is the volume of the resonant cavity, W is the total energy storage of the resonant cavity, and W e is the electric field energy storage. Similarly, by calculating the energy storage in different regions, the total energy storage of the resonant cavity W can be obtained by summing them up. total .

[0060] At this time, the resonant cavity Q c Easy to find:

[0061]

[0062] Assume that the microwave power P that excites the resonant cavity is TEM003 All the energy is injected into the resonant cavity, and only the cavity wall loss is considered. The electric field strength in the area where the chip under test is located, which is defined by the quality factor, can be expressed as follows:

[0063]

[0064] Step 3. Calculate the input power P of the chip under test 3 measured in steps 1 and 2. in and output power P out , calculate the performance parameters gain G and efficiency η respectively. The specific calculation process is as follows:

[0065]

[0066] Among them, U s is the power supply voltage, I d is the drain current, which can be measured directly by an ammeter;

[0067] Statistical gain G and efficiency η are used to further analyze the impact of the microwave electric field on the performance of the chip 3 under test;

[0068] Step 4. Change the input power of the first signal source 7 to obtain different microwave electric field intensities in the test area. Repeat steps 2 to 3 to obtain the impact level of the amplifier chip performance under different microwave electric fields.

[0069] The above description is only a specific embodiment of the present invention. Any feature disclosed in this specification, unless otherwise stated, can be replaced by other equivalent or alternative features with similar purposes; all disclosed features, or all steps in the methods or processes, except for mutually exclusive features and / or steps, can be combined in any way.

Claims

1. A system for testing the impact of strong microwave electric fields on amplifier chip performance, characterized by: It includes a reentrant resonant cavity main cavity, a reentrant resonant cavity upper cover, a microwave electrical probe, a first power meter, a second power meter, a first signal source, a second signal source, a power supply, a power amplifier and a directional coupler; The first signal source is connected to one port of a power amplifier, and the other port of the power amplifier is connected to the incident end of a directional coupler; the through end of the directional coupler is connected to a microwave electrical probe, the coupling end of the directional coupler is connected to a first power meter, and the reflection end of the directional coupler is connected to a matching load; the microwave electrical probe is arranged in the main cavity of the reentrant resonant cavity at a distance not exceeding one-third of the cavity length from the bottom; A cylindrical protrusion is provided at the center of the upper cover of the reentrant resonant cavity, and the chip to be tested is fixedly provided on the protrusion. The power pin of the chip to be tested passes through the upper cover of the reentrant resonant cavity and is connected to the power supply. The input pin passes through the upper cover of the reentrant resonant cavity and is connected to the second signal source. The output pin passes through the upper cover of the reentrant resonant cavity and is connected to the second power meter. The main cavity of the reentrant resonant cavity consists of a hollow cylindrical outer conductor and an inner conductor arranged concentrically with the outer conductor. The lower end surface of the inner conductor is fixedly connected to the lower bottom surface of the outer conductor. A through hole is set in the center of the upper top surface of the outer conductor. The diameter of the through hole is the same as the size of the cylindrical protrusion of the upper cover of the reentrant resonant cavity. The height of the through hole is the same as the height of the cylindrical protrusion of the upper cover of the reentrant resonant cavity. The upper cover of the reentrant resonant cavity is completely matched with the upper top surface of the reentrant resonant cavity main cavity, and the upper end surface of the inner conductor does not contact the chip to be tested. The test system is tested according to the following steps: Step 1. Turn off the first signal source and use the second signal source to read the input power P of the chip under test when there is no microwave electric field. in1 , and use the second power meter to measure the output power P of the chip under test out1 ; Step 2. Turn on the first signal source to excite the microwave electric field in the main cavity of the reentrant resonant cavity, adjust the power amplifier to the required microwave electric field intensity, and use the second signal source to read the input power P of the chip under test. in2 , and use the second power meter to measure the output power P of the chip under test out2 ; Step 3. Based on the input power P of the chip under test obtained in steps 1 and 2 in1 、P in2 and output power P out1 、P out2 , calculate the gain G and efficiency η respectively. The specific calculation process is as follows: Among them, U s is the power supply voltage, I d is the drain current; Step 4. Compare the gain G and efficiency η with and without the microwave electric field to analyze the impact of the strong microwave electric field on the performance of the amplifier chip.

2. The system for testing the impact of strong microwave electric fields on amplifier chip performance as claimed in claim 1, characterized in that: The length of the microwave electric probe penetrating into the main cavity of the reentrant resonant cavity is adjusted to adjust the coupling matching degree between the microwave electric probe and the reentrant resonant cavity.

3. The system for testing the impact of strong microwave electric fields on amplifier chip performance as claimed in claim 1, characterized in that: The chip to be tested is fixed to the cylindrical protrusion of the upper cover of the reentrant resonant cavity by screws. When the upper cover of the reentrant resonant cavity completely overlaps with the top surface of the main cavity of the reentrant resonant cavity, the chip to be tested is located at a location where the microwave electric field is evenly distributed in the main cavity of the reentrant resonant cavity.

4. The system for testing the impact of strong microwave electric fields on amplifier chip performance as claimed in claim 1, characterized in that: The working mode of the main cavity of the reentrant resonator is TEM 00n mode, where n represents the nth mode.

5. The system for testing the impact of strong microwave electric fields on amplifier chip performance as claimed in claim 1, characterized in that: Inner conductor height l and electromagnetic wave resonance wavelength λ r The relationship is: l = (2n-1)λ r / 4.

6. The system for testing the impact of strong microwave electric fields on amplifier chip performance as claimed in claim 1, characterized in that: The diameter r of the inner conductor is greater than or equal to 1.5 times the width of the chip to be tested; the distance d between the upper end surface of the inner conductor and the top surface of the outer conductor is greater than or equal to 3 times the thickness of the chip to be tested.

7. The system for testing the impact of strong microwave electric fields on amplifier chip performance as claimed in claim 1, characterized in that: In step 2, the microwave electric field intensity is changed by adjusting the power input into the reentrant cavity.

8. The system for testing the impact of strong microwave electric fields on amplifier chip performance as claimed in claim 7, characterized in that: The relationship between the microwave electric field intensity and the input power of the reentrant cavity is as follows: adjust the excitation signal frequency so that the reentrant cavity works at TEM 00n Mode, mode matching method is used to partition the mode. For any area, if only the conductance loss caused by the cavity wall is considered in the reentrant resonant cavity, the cavity loss P c for: Among them, R s is the surface resistivity, H φ is the magnetic field intensity in the φ direction, wall represents the total area of ​​the cavity wall in this area, and s is the area. Since the electromagnetic field distribution in each partition is different, the conductivity loss of each area is calculated according to the different positions of the reentrant resonant cavity wall and the different areas of the electromagnetic field, and the cavity loss P is obtained by summing them up. c总 ; The total energy storage formula of the resonant cavity in each region of the electromagnetic field is: Where V is the volume of the reentrant cavity, W is the total energy storage in the cavity, and W e is the electric field energy storage, ε r is the relative dielectric constant, ε0 is the vacuum dielectric constant, is the electric field strength; By calculating the energy storage in different regions, the total energy storage of the resonant cavity W can be obtained by summing up. total ; At this time, the resonant cavity quality factor Q c Easy to find: Where ω0 is the resonant angular frequency; Assume that the microwave power TEM of the excitation cavity is 00n All is injected into the resonant cavity, and only the cavity loss P is considered. c , by the quality factor Q c The electric field strength in the area where the chip to be tested is located can be expressed as follows:

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