A method of testing a flexible microwave antenna / filter

Abstract

The present application relates to a kind of flexible microwave antenna / filter testing method, which is completed in the same test device in the stretching, bending, twisting, kneading process online testing the microwave characteristics of flexible microwave antenna / filter;When testing, one side of flexible microwave antenna / filter is fixed, and the other side is clamped on the fixture of XYZθ four-degree-of-freedom moving platform, wherein the movement of X, Y, Z, θ four degrees of freedom is independently adjustable, by controlling the movement of X, Y, Z, θ four degrees of freedom single or combination, realize that flexible microwave antenna / filter is stretched, bent, twisted, kneaded, microwave testing instrument is connected to flexible microwave antenna / filter online, realize in the same test device in the stretching, bending, twisting, kneading process online testing the microwave characteristics of flexible microwave antenna / filter.

Description

TECHNICAL FIELD

[0001] The present application relates to a method for testing a flexible microwave antenna / filter. BACKGROUND

[0002] Flexible microwave antennas and filters are widely used in modern electronic devices due to their lightweight and bendable characteristics. With the rapid development of wearable devices, flexible display technology, and the Internet of Things, there is an increasing demand for high-performance, deformable microwave components that can be integrated into these devices. These antennas and filters not only need to function in traditional communication devices, but also need to adapt to various extreme environmental conditions, such as maintaining performance stability when bending, folding, or stretching.

[0003] In wearable scenarios, flexible microwave antennas and filters may face various mechanical deformations such as stretching, bending, twisting, and rubbing. These deformations can have a significant impact on the microwave characteristics of the antennas and filters, including impedance changes, resonance frequency shifts, and changes in radiation patterns. For example, when a flexible antenna works in a bent state, its electrical length and impedance will change, which may lead to a decrease in signal transmission efficiency. In addition, twisting and rubbing may introduce additional losses, affecting the integrity of the signal. Therefore, designing flexible microwave antennas and filters that can maintain performance stability under these complex mechanical deformations is crucial for realizing high-performance wearable electronic devices.

[0004] At the same time, flexible microwave antennas and filters may face various mechanical deformations such as stretching, bending, twisting, and rubbing, which may also cause the metal thin film layer to strain due to stress, leading to an increase in resistivity or even breakage, affecting the electrical function of the flexible microwave antenna and filter. When designing flexible microwave antennas and filters, their possible mechanical deformations in actual application need to be considered, including stretching, bending, twisting, and rubbing. The metal thin film layer is a key part of the antenna and filter, and when subjected to mechanical deformation, it may suffer from various adverse effects due to stress:

[0005] (1) Increase in resistivity: When the metal thin film is subjected to tensile or compressive stress, its internal structure may experience lattice distortion, leading to a decrease in electron mobility and thus an increase in resistivity.

[0006] (2) Breakage: If the stress of the metal thin film layer exceeds the yield strength of the material, it may lead to breakage of the metal thin film layer, especially under bending or twisting deformation, the edges or local areas of the film may break due to stress concentration.

[0007] (3) Fatigue damage: Even if the metal thin film layer does not immediately break, repeated mechanical deformation may cause fatigue damage, and after a certain period of deformation, the metal thin film layer may suddenly break.

[0008] (4) Electrical function degradation: The fracture or resistivity increase of the metal thin film layer can cause the electrical function degradation of the antenna and filter, including signal transmission loss increase, frequency response characteristic change, etc.

[0009] (5) Reliability reduction: Long-term mechanical deformation can reduce the reliability of the metal thin film layer, which may suddenly fail at an unknown time, which is unacceptable for applications requiring high reliability, such as medical devices, safety monitoring, etc.

[0010] Testing the microwave characteristics of flexible microwave antennas and filters under different mechanical deformations is crucial to ensure their reliability and performance. These tests can help designers understand the behavior of materials under actual use conditions, thereby optimizing design and material selection. However, existing testing methods often only focus on performance changes under bending conditions, ignoring the effects of stretching, twisting, and rubbing. This limitation may cause deviations between the actual performance of antennas and filters in practical applications and expectations. Therefore, developing a comprehensive testing method that can simulate and evaluate the microwave characteristics of flexible microwave antennas and filters under various mechanical deformations is of great significance to the development of flexible electronics technology.

[0011] Currently, there are some obvious shortcomings in the testing methods of flexible microwave antennas and filters. First, these tests are usually only performed before and after deformation, without considering real-time performance changes during deformation, which limits the understanding of the performance of antennas and filters in actual use. Second, the current mechanical deformation tests of flexible microwave antennas and filters only include bending tests, i.e., manually bending the flexible microwave antennas and filters several times and then testing their microwave characteristics. Third, different deformation tests require the use of different devices, which not only increases the complexity of testing but also increases costs. In addition, existing testing methods are tested by manually bending flexible microwave antennas and filters using a specific radius of a cylinder (as shown in Figure 1 and Figure 2 ), which has low automation and cannot adapt to thousands of endurance tests or simulate microwave characteristics tests under different bending radii and different bending times.

[0012] Therefore, there is an urgent need for a simple and efficient testing method that can simultaneously test the effects of multiple mechanical deformations. SUMMARY

[0013] The purpose of the present application is to develop a new test method for comprehensively evaluating the microwave characteristics of flexible microwave antennas and filters under various mechanical deformations including stretching, bending, twisting and kneading, with the radius, amplitude and angle of bending, twisting and kneading freely adjustable, and the test fully automated, completely avoiding the annoyance of manual operation.

[0014] This method aims to overcome the limitations of existing test techniques and provide a solution that can monitor and analyze the performance of antennas and filters in actual use conditions in real time. Through this test method, the behavior of materials under complex mechanical stress can be better understood, thereby optimizing the design and improving the performance and reliability of flexible microwave antennas and filters to meet the needs of wearable electronic devices and other flexible electronic applications.

[0015] The technical solution of the present application can complete the microwave characteristic test of flexible microwave antennas / filters under various complex mechanical stresses using a simple set of instrument equipment, and realize online microwave characteristic test during stretching, bending, twisting and kneading.

[0016] The specific technical solution to achieve the purpose of the present application is:

[0017] A test method for flexible microwave antennas / filters, which completes online testing of the microwave characteristics of flexible microwave antennas / filters during stretching, bending, twisting and kneading on the same test device.

[0018] During testing, one side of the flexible microwave antenna / filter is fixed, and the other side is clamped on the clamp of the XYZθ four-degree-of-freedom moving table, wherein the movements of the four degrees of freedom X, Y, Z and θ are independently adjustable. By controlling the movement of the four degrees of freedom X, Y, Z and θ in single or combination, the flexible microwave antenna / filter is stretched, bent, twisted and kneaded. The microwave test instrument is connected online to the flexible microwave antenna / filter to realize online testing of the microwave characteristics of the flexible microwave antenna / filter during stretching, bending, twisting and kneading. In the present application, the XYZθ four-degree-of-freedom moving table belongs to a mature existing device, and there are various commercial models to choose from, so it is not described in detail here.

[0019] To realize online testing of the microwave characteristics of flexible microwave antennas / filters during stretching, bending, twisting and kneading on the same test device, including:

[0020] (1) Stretching test: by controlling the X-axis direction drive block of the XYZθ four-degree-of-freedom moving table to apply a periodically varying tensile force, simulating stretching deformation, and using a microwave test instrument to monitor the performance changes of the antenna and filter in real time;

[0021] (2) Bending test: periodically change the displacement of the X-axis direction driving block of the XYZθ four-degree-of-freedom moving table to simulate bending deformation, and record the change of microwave characteristics;

[0022] (3) Torsion test: periodically change the displacement of the Y-axis direction driving block to simulate torsion deformation, and test the microwave characteristics; preferably, the X-axis or Z-axis direction driving block can also be controlled to periodically change the displacement to simulate torsion deformation;

[0023] (4) Rubbing test: periodically change the displacement of the Y-axis and Z-axis direction driving blocks to simulate rubbing deformation, and test the microwave characteristics.

[0024] The test method specifically includes the following steps:

[0025] (1) Fix the opposite edges of the manufactured flexible microwave antenna / filter on the left and right clamps, respectively, wherein the left clamp is fixed on the left vertically arranged support plate, and the right clamp is fixed on the right vertically arranged XYZθ four-degree-of-freedom moving table; in the initial state, the fixed points of the left and right clamps are opposite and the clamping surfaces are in the same plane; the movements of each degree of freedom of the XYZθ four-degree-of-freedom moving table are driven by a motor; the left and right clamps also have a gold finger and a signal interface of a microwave test instrument electrically connected to the gold finger, and the gold finger is used to electrically connect the flexible microwave antenna / filter to the microwave test instrument;

[0026] When the flexible microwave antenna / filter is clamped by the clamp, the signal input and output end is pressed on the gold finger;

[0027] (2) Drive the XYZθ four-degree-of-freedom moving table so that the flexible microwave antenna / filter is stretched, bent, twisted, and rubbed, respectively, while being stretched, bent, twisted, and rubbed, the microwave test instrument tests the microwave characteristics of the flexible microwave antenna / filter and records the data;

[0028] (3) According to the test data obtained in step (2), evaluate the stretch resistance, bending resistance, torsion resistance, and rubbing resistance of the flexible microwave antenna / filter.

[0029] In step (2), the implementation is as follows:

[0030] (2-1) Stretching test: input the control signal of the XYZθ four-degree-of-freedom moving table, drive the X-axis direction driving block of the XYZθ four-degree-of-freedom moving table to gradually increase the pulling force to a preset value away from the fixed clamp on the right side, and then gradually return to zero value, the pulling force equation of the X-axis direction driving block is , wherein F maxis a preset maximum tensile force, t is time, n is a parameter, X, Y, Z, θ remain unchanged during the tensile test, so that the flexible microwave antenna / filter under test is gradually stretched to the preset value and then gradually returned to zero, the microwave test instrument continuously tests and records data during the stretching process; the operation is repeated a preset number of times; the tensile force is tested by a tensile force sensor connected to the clamp;

[0031] (2-2) Bending test: input the control signal of the XYZθ four-degree-of-freedom moving table, drive the X-axis direction driving block of the XYZθ four-degree-of-freedom moving table, and the X-axis direction driving block motion equation is , wherein A is a preset maximum X-axis direction displacement, t is time, n is a parameter, Y, Z, θ remain unchanged, so that the flexible microwave antenna / filter under test is gradually bent to a preset radian and then gradually returned to a flat state, the microwave test instrument continuously tests and records data during the bending process, and the operation is repeatedly performed a preset number of times;

[0032] (2-3) Twisting test: input the control signal of the XYZθ four-degree-of-freedom moving table, drive the Y-axis direction driving block of the XYZθ four-degree-of-freedom moving table, and the Y-axis direction driving block motion equation is , wherein B is a preset maximum Y-axis direction displacement, t is time, m is a parameter, X, Z remain unchanged, θ remains unchanged or changes at a preset fixed period, so that the flexible microwave antenna / filter under test is repeatedly twisted, the microwave test instrument continuously tests and records data during the twisting process, and the operation is repeatedly performed a preset number of times;

[0033] (2-4) Rubbing test: input the control signal of the XYZθ four-degree-of-freedom moving table, drive the Y-axis direction driving block and the Z-axis direction driving block of the XYZθ four-degree-of-freedom moving table, the Y-axis direction driving block motion equation is , wherein B is a preset maximum Y-axis direction displacement, the Z-axis direction driving block motion equation is , wherein C is a preset maximum Z-axis direction displacement, t is time, m, p are parameters, θ remains unchanged or changes at a preset fixed period; X is fixed as D, so that when the Y-axis direction driving block and the Z-axis direction driving block are at the initial position, the distance between the left clamp and the right clamp is less than half the length of the flexible microwave antenna / filter under test; after the Y-axis direction driving block and the Z-axis direction driving block start to move, the flexible microwave antenna / filter under test is repeatedly rubbed, the microwave test instrument continuously tests and records data during the rubbing process, and the operation is repeatedly performed a preset number of times;

[0034] In steps (2-1), (2-2), (2-3), and (2-4), as soon as the appearance of the flexible microwave antenna / filter is torn or damaged, worn out, or the microwave characteristics obtained by the microwave testing instrument deviate from the design value by a preset tolerance value, the test is terminated and enters step (3).

[0035] Beneficial technical effects

[0036] The beneficial technical effects that the technical solutions of the present application can bring mainly include:

[0037] (1) Comprehensive testing: online testing during stretching, bending, twisting, and rubbing processes can be completed on the same testing device, and the changes in microwave characteristics of flexible microwave antennas and filters under various mechanical deformations can be comprehensively evaluated.

[0038] (2) Automated testing: the testing process can be automated, avoiding the annoyance of manual operation and improving the efficiency and accuracy of testing.

[0039] (3) Real-time performance monitoring: by connecting the microwave testing instrument online, the performance of the antenna and filter under actual use conditions can be monitored and analyzed in real time, providing a deeper understanding of material behavior.

[0040] (4) Optimized design: test data can help optimize design and material selection, improving the performance and reliability of flexible microwave antennas and filters.

[0041] (5) Improved reliability: by simulating mechanical deformation in actual use, the long-term reliability of the product can be evaluated and improved, especially in application scenarios requiring high reliability.

[0042] (6) Reduced cost: using one set of equipment to complete multiple tests reduces the cost of separate testing with different devices.

[0043] (7) Enhanced durability: through testing and analysis, the behavior of materials under complex mechanical stress can be better understood, leading to the design of more durable products.

[0044] (8) Improved adaptability: the testing method can adapt to different bending radii, bending frequencies, and deformation types, improving the flexibility and adaptability of the testing method.

[0045] (9) Standardized testing process: provides a standardized testing process, which helps ensure the consistency and comparability of product quality.

[0046] (10) Promote the development of flexible electronic technology: this testing method helps promote the development of flexible electronic technology, meeting the needs of wearable electronic devices and other flexible electronic applications.

[0047] Statement: The technical contents not specially explained in the invention are all the existing technologies in the field, which do not need to be specifically and detailedly explained and do not affect the full disclosure of the invention. BRIEF DESCRIPTION OF DRAWINGS

[0048] Figure 1 : Bending test figure in prior art (our prior application CN2022100007490), manual bending.

[0049] Figure 2 : Bending test figure in prior art (our prior application CN2022100007490), manual bending with the aid of a cylindrical foam.

[0050] Figure 3 : A commercial XYZθ four-degree-of-freedom moving table adopted by the invention, the fixture, and the flexible microwave antenna / filter in the figure have not been installed. DETAILED DESCRIPTION

[0051] In order to facilitate the understanding of the invention, the technical solutions of the invention will be specifically introduced below in combination with examples.

[0052] The invention completes the online testing of the microwave characteristics of the flexible microwave antenna / filter in the stretching, bending, twisting, and rubbing processes on the same test device;

[0053] During the test, one side of the flexible microwave antenna / filter is fixed, and the other side is clamped on the fixture of the XYZθ four-degree-of-freedom moving table, wherein the movements of the four degrees of freedom X, Y, Z, and θ are independently adjustable, and the single or combination of the movements of the four degrees of freedom X, Y, Z, and θ is controlled, as shown in Figure 3 , to realize the stretching, bending, twisting, and rubbing of the flexible microwave antenna / filter. The microwave testing instrument is connected to the flexible microwave antenna / filter online to realize the online testing of the microwave characteristics of the flexible microwave antenna / filter in the stretching, bending, twisting, and rubbing processes on the same test device.

[0054] When specifically implemented, the method for completing the stretching, bending, twisting, and rubbing processes of the flexible microwave antenna / filter on the same test device can be realized through the following steps:

[0055] 1. Fixing and clamping: First, fix one side of the flexible microwave antenna / filter at one end of the test device to ensure that this end does not move during the test. The other side is clamped on the fixture of the XYZθ four-degree-of-freedom moving table.

[0056] Independent control: The XYZθ four-degree-of-freedom moving table has independent control capability and can accurately control the translation in the X, Y, and Z directions and the rotation in the θ direction.

[0057] 2. Stretching test: By controlling the movement of the X or Y direction stage, a stretching force can be applied to the antenna / filter, simulating the stretching deformation that may be encountered in actual use.

[0058] 3. Bending test: By controlling the movement of the Z direction stage, a bending deformation can be simulated. At the same time, by adjusting the rotation of the θ direction, the angle and direction of the bending can be controlled.

[0059] 4. Twisting test: By combining the control of the X, Y, and Z direction stages, a twisting deformation can be simulated. For example, first stretch in the X direction, then bend in the Y direction, while adjusting the θ rotation to achieve the twisting effect.

[0060] 5. Rubbing test: Rubbing can be simulated by alternating stretching and compression in the X and Y directions. By precisely controlling the movement path and speed of the stages, an effect similar to manual rubbing can be achieved.

[0061] Online testing: While performing the above deformation tests, the microwave test instrument is connected online to the flexible microwave antenna / filter, monitoring its microwave characteristics in real time.

[0062] 6. Data recording and analysis: During the test, the changes in the microwave characteristics of the antenna / filter are recorded by the data acquisition system, and data analysis is performed by the analysis software to evaluate its performance.

[0063] Cyclic testing: To comprehensively evaluate the performance of the antenna / filter, the above stretching, bending, twisting, and rubbing tests can be performed in cycles to simulate various possible situations in actual use.

[0064] Through the above steps, the microwave characteristics test of flexible microwave antenna / filter under different mechanical deformation states can be completed on one test device, providing a scientific basis for design and improvement.

[0065] It should be particularly noted that in the description of the present application, the X, Y, and Z three degrees of freedom of the XYZθ four-degree-of-freedom stage do not have specific meanings, i.e., the X, Y, and Z three degrees of freedom are independent and interchangeable, for example, the motion of the X degree of freedom moving block can be controlled independently, and the other degrees of freedom remain unchanged; or the motion of the Y degree of freedom moving block can be controlled independently, and the other degrees of freedom remain unchanged; or the motion of the Z degree of freedom moving block can be controlled independently, and the other degrees of freedom remain unchanged. It depends on the installation orientation of the XYZθ four-degree-of-freedom stage and the positional relationship with the flexible microwave antenna / filter.

[0066] More specifically, as an example, the following is described:

[0067] The test method specifically includes the following steps:

[0068] (1) the opposite edges of the finished flexible microwave antenna / filter are fixed on the left and right clamps respectively, wherein the left clamp is fixed on the left vertical support plate, and the right clamp is fixed on the right vertical XYZθ four-degree-of-freedom moving table; in the initial state, the left and right clamp fixed points are opposite and the clamping surfaces are in the same plane; the movement of each degree of freedom of the XYZθ four-degree-of-freedom moving table is driven by a motor;

[0069] The left and right clamps also have a gold finger and a signal interface of a microwave test instrument electrically connected to the gold finger, and the gold finger is used to electrically connect the flexible microwave antenna / filter to the microwave test instrument;

[0070] When the flexible microwave antenna / filter is clamped by the clamp, the signal input and output end is pressed on the gold finger;

[0071] (2) drive the XYZθ four-degree-of-freedom moving table so that the flexible microwave antenna / filter is stretched, bent, twisted and rubbed respectively, while being stretched, bent, twisted and rubbed, the microwave test instrument tests the microwave characteristics of the flexible microwave antenna / filter and records the data; the specific implementation is as follows:

[0072] (2-1) stretching test: input the control signal of the XYZθ four-degree-of-freedom moving table, drive the X-axis direction driving block of the XYZθ four-degree-of-freedom moving table to gradually increase the pulling force to the preset value and then gradually return to zero value in the direction away from the right fixed clamp, the pulling force equation of the X-axis direction driving block is , wherein F max is the preset maximum pulling force, t is the time, n is the parameter, X, Y, Z and θ remain unchanged, so that the tested flexible microwave antenna / filter is gradually stretched to the preset value and then gradually returns to zero, and the microwave test instrument continuously tests and records the data during the stretching process; repeat the operation for a preset number of times;

[0073] (2-2) bending test: input the control signal of the XYZθ four-degree-of-freedom moving table, drive the X-axis direction driving block of the XYZθ four-degree-of-freedom moving table, the movement equation of the X-axis direction driving block is , wherein A is the preset maximum X-axis direction displacement, t is the time, n is the parameter, Y, Z and θ remain unchanged, so that the tested flexible microwave antenna / filter is gradually bent to the preset radian and then gradually returns to the flat state, and the microwave test instrument continuously tests and records the data during the bending process; repeat the operation for a preset number of times;

[0074] (2-3) Distortion test: input control signals of the XYZθ four-degree-of-freedom moving stage, drive the Y-axis direction driving block of the XYZθ four-degree-of-freedom moving stage, and the Y-axis direction driving block movement equation is , wherein B is a preset maximum Y-axis direction displacement, t is time, m is a parameter, X and Z remain unchanged, and θ remains unchanged or is preset to change periodically, so that the flexible microwave antenna / filter under test is repeatedly distorted, and the microwave test instrument continuously tests and records data, and the operation is repeatedly performed for a preset number of times;

[0075] (2-4) Rubbing test: input control signals of the XYZθ four-degree-of-freedom moving stage, drive the Y-axis direction driving block and the Z-axis direction driving block of the XYZθ four-degree-of-freedom moving stage, the Y-axis direction driving block movement equation is , wherein B is a preset maximum Y-axis direction displacement, the Z-axis direction driving block movement equation is , wherein C is a preset maximum Z-axis direction displacement, t is time, m and p are parameters, θ remains unchanged or is preset to change periodically, and X is fixed as D, so that when the Y-axis direction driving block and the Z-axis direction driving block are at the initial position, the distance between the left clamp and the right clamp is less than half the length of the flexible microwave antenna / filter under test; after the Y-axis direction driving block and the Z-axis direction driving block start to move, the flexible microwave antenna / filter under test is repeatedly rubbed, and the microwave test instrument continuously tests and records data, and the operation is repeatedly performed for a preset number of times;

[0076] Here, the steps (2-1), (2-2), (2-3), and (2-4) are not in any particular order.

[0077] In the steps (2-1), (2-2), (2-3), and (2-4), as long as the flexible microwave antenna / filter appears to be torn or damaged, worn, or the microwave characteristic parameters obtained by the microwave test instrument deviate from the design value by a preset tolerance, the test is immediately terminated and enters step (3).

[0078] (3) According to the test data obtained in step (2), evaluate the stretch resistance, bending resistance, distortion resistance, and rubbing resistance of the flexible microwave antenna / filter.

[0079] Similarly, the above X, Y, and Z degrees of freedom can be interchanged under certain conditions, depending on the installation orientation of the XYZθ four-degree-of-freedom moving stage and the positional relationship of the flexible microwave antenna / filter, and are not a limitation.

[0080] As a general description, another embodiment is as follows:

[0081] (A) Test preparation:

[0082] Fixing the antenna / filter: Fix the two side edges of the flexible microwave antenna / filter on the left and right clamps respectively. The left clamp is fixed on the support plate, and the right clamp is fixed on the XYZθ four-degree-of-freedom moving table.

[0083] Connecting the test instrument: Use the gold finger and signal interface to electrically connect the antenna / filter to the microwave test instrument.

[0084] Clamping the antenna / filter: Ensure that the signal input and output ends of the antenna / filter are tightly connected with the gold finger when clamped by the clamp.

[0085] (B) Test steps:

[0086] (B1) Tensile test (2-1)

[0087] Control signal input: Input control signal to XYZθ four-degree-of-freedom moving table.

[0088] Tensile motion: The X-axis direction drive block follows the equation Tensile flexible microwave filter / antenna, where F max is the preset maximum tensile force, t is time, n is the parameter, X, Y, Z, θ remain unchanged.

[0089] Test recording: The microwave test instrument continuously tests and records data during the stretching process.

[0090] Repeat operation: Repeat a preset number of times.

[0091] (B2) Bending test:

[0092] Control signal input: Input control signal to XYZθ four-degree-of-freedom moving table.

[0093] Bending motion: The X-axis direction drive block follows the equation , where A is the preset maximum X-axis direction displacement, t is time, n is the parameter, Y, Z, θ remain unchanged.

[0094] Test recording: The microwave test instrument continuously tests and records data during the bending process.

[0095] Repeat operation: Repeat a preset number of times.

[0096] (B3) Twisting test:

[0097] Control signal input: Input control signal to XYZθ four-degree-of-freedom moving table.

[0098] Twist motion: The Y-axis direction drive block twists according to the equation Y=B∣sin(mt)∣.

[0099] Test recording: The microwave test instrument continuously tests and records data during the twisting process.

[0100] Repeat operation: Repeat a preset number of times.

[0101] (B4) Rubbing test:

[0102] Control signal input: Input control signals to the XYZθ four-degree-of-freedom moving stage.

[0103] Rubbing motion: The Y-axis and Z-axis direction driving blocks respectively follow the equations , , for rubbing, where C is the preset maximum Z-axis direction displacement, t is time, m, p are parameters, and θ remains unchanged or changes periodically.

[0104] Test recording: The microwave test instrument continuously tests and records data during the rubbing process.

[0105] Repeat operation: Repeat a preset number of times.

[0106] Test termination condition

[0107] Appearance inspection: If the antenna / filter has tears, damage, or wear.

[0108] Performance check: If the microwave characteristic parameters deviate from the design values within the preset tolerance.

[0109] (C) Performance evaluation

[0110] Data analysis: Analyze the test data obtained in step (2).

[0111] Performance evaluation: Evaluate the stretch resistance, bend resistance, twist resistance, and rubbing resistance of the flexible microwave antenna / filter.

[0112] Notes: Degree of freedom exchange: X, Y, and Z degrees of freedom can be exchanged under certain conditions, depending on the installation orientation of the moving stage and the position relationship of the antenna / filter.

[0113] Through the above steps, the microwave performance of the flexible microwave antenna / filter under mechanical stress can be comprehensively evaluated, ensuring its reliability in actual application.

[0114] Example 1: Standard test procedure

[0115] 1. Preparation phase:

[0116] Fix the flexible microwave antenna / filter on the left and right clamps of the test device.

[0117] Connect the microwave test instrument to ensure normal signal transmission.

[0118] 2. Stretching test:

[0119] The X-axis direction tension is gradually increased to the maximum value, maintained for a period of time, and then gradually decreased to zero according to the preset maximum tension value.

[0120] The microwave tester records the microwave characteristics during the entire stretching process.

[0121] 3. Bending test:

[0122] The X-axis direction displacement maximum value n is set to gradually bend the antenna / filter to the preset radian.

[0123] The microwave tester records the data during the bending process.

[0124] 4. Twisting test:

[0125] The Y-axis direction displacement maximum value is set to perform periodic twisting motion.

[0126] The microwave tester records the data during the twisting process.

[0127] 5. Rubbing test:

[0128] The Y-axis and Z-axis direction displacement maximum values B and C, as well as the parameters m and p, are set to perform rubbing motion.

[0129] The microwave tester records the data during the rubbing process.

[0130] 6. Performance evaluation:

[0131] The test data is analyzed to evaluate the mechanical stress resistance performance of the antenna / filter.

[0132] Example 2: Accelerated life test

[0133] 1. High temperature environment test:

[0134] The test procedure of Example 1 is repeated in a high temperature environment to accelerate the material aging process.

[0135] 2. Humidity environment test:

[0136] The test procedure of Example 1 is repeated in a high humidity environment to evaluate the performance of the antenna / filter under wet conditions.

[0137] 3. Mechanical stress and environmental factor combined test:

[0138] The test is combined with high temperature, high humidity and mechanical stress (stretching, bending, twisting, rubbing) to simulate extreme use conditions.

[0139] Example 3: Comparison test of different materials

[0140] 1. Material A test:

[0141] Test procedure of Example 1 is performed using flexible microwave antennas / filters made of Material A.

[0142] 2. Material B Test:

[0143] Same test procedure is performed using flexible microwave antennas / filters made of Material B.

[0144] 3. Performance Comparison:

[0145] Compare the performance differences of the two materials under the same test conditions.

[0146] Example 4: Testing of Different Design Structures

[0147] 1. Design A Test:

[0148] Test procedure of Example 1 is performed on antennas / filters with a specific design structure A.

[0149] 2. Design B Test:

[0150] Same test procedure is performed on antennas / filters with a different design structure B.

[0151] 3. Structure Optimization:

[0152] Based on the test results, evaluate the impact of different designs on performance and perform structure optimization.

[0153] Example 5: Actual Application Simulation Test

[0154] 1. Simulation Usage Scenario A:

[0155] Simulate the usage of antennas / filters in scenario A (e.g., wearable devices with repeated folding).

[0156] 2. Simulation Usage Scenario B:

[0157] Simulate the usage of antennas / filters in scenario B (e.g., flexible displays that are often twisted).

[0158] 3. Scenario Adaptability Evaluation:

[0159] Based on the test results, evaluate the adaptability of antennas / filters to different usage scenarios.

[0160] When implementing the above examples, appropriate adjustments and optimizations should be made according to actual needs and conditions.

[0161] In the previous examples, in steps (2-4), m≠p, so that the right clamp is driven by the Y-axis direction driving block and the Z-axis direction driving block to make a clothoid curve motion in the vertical plane, so that the flexible microwave antenna / filter is repeatedly rubbed;

[0162] Preferably, between 3 and 10, or between 3 and 10;

[0163] Preferably, or are both decimal numbers, i.e. m, p are not integer ratios. The advantage of this setting is that, in the motion plane, the Y-axis direction driving block and the Z-axis direction driving block drive the right clamp to make a clothoid curve motion in the vertical plane, which is more complex, and the motion trajectory can cover more planes, which means that the flexible microwave filter / antenna can withstand more stress tests under different combinations of bending radii and twisting angles.

[0164] In step (2-4), X is fixed as D, so that when the Y-axis direction driving block and the Z-axis direction driving block are in the initial position, the distance between the left clamp and the right clamp is less than 1 / 5 of the length of the flexible microwave antenna / filter to be tested. This can ensure that the flexible microwave antenna / filter to be tested can better simulate the kneading action. If the distance between the left clamp and the right clamp is too large, the flexible microwave antenna / filter to be tested can only form a wavy line shaking, which is insufficient to simulate the kneading action.

[0165] In step (2-2), A is half of the length of the flexible microwave antenna / filter to be tested.

[0166] In step (2-3), the change period of θ is the same as the period of the Y-axis direction driving block.

[0167] In various embodiments of the present application, flexible coaxial cables are used to electrically connect the gold fingers of the left and right clamps to the interface of the microwave test instrument, and the coaxial cables are kept in a relaxed state to ensure that the coaxial cables will not be pulled tight during the stretching, bending, twisting and kneading of the flexible microwave antenna / filter.

[0168] In various embodiments of the present application, for a flexible microwave filter, one or more of the following microwave characteristics are tested during the stretching, bending, twisting and kneading process:

[0169] Frequency response: test the response of the filter at different frequencies, including the performance of the passband and the stopband;

[0170] Insertion loss: measure the degree of attenuation of the signal passing through the filter;

[0171] Return loss: represents the loss of the reflected signal at the input end of the filter;

[0172] Isolation: test the isolation between different signal paths in the filter;

[0173] VSWR: Test the degree of impedance matching between the filter and other parts of the system;

[0174] In various embodiments of the present application, for flexible microwave filters, one or more of the following microwave characteristics are tested during stretching, bending, twisting, kneading:

[0175] Operating frequency: Test whether the operating frequency range of the antenna meets the design requirements;

[0176] Gain: Test the radiation or reception capability of the antenna;

[0177] Radiation pattern: Including the shape of the main lobe and side lobes, and their relative intensity;

[0178] Impedance matching: Test whether the impedance of the antenna input matches the system;

[0179] Polarization characteristics: Test the polarization mode and performance of the antenna;

[0180] Directivity: Test the directionality of the antenna in radiating or receiving signals.

[0181] In various embodiments of the present application, the microwave test instrument adopts one or a combination of the following devices to meet different testing requirements and standards:

[0182] (a) Vector Network Analyzer (VNA): Used to measure network parameters such as VSWR, return loss, insertion loss;

[0183] (b) Spectrum analyzer: Used to measure the spectral characteristics of signals such as frequency range, power distribution;

[0184] (c) Microwave darkroom: Provides a non-reflective test environment for antenna pattern measurement and radiation characteristic analysis;

[0185] (d) Signal generator: Used to generate test signals to simulate the signal environment under actual working conditions.

[0186] (e) Power meter: Used to measure the power level of signals;

[0187] (f) Antenna test system: Including turntable, polarizer, RF amplifier, for comprehensive testing of antenna performance such as gain, polarization characteristics, directivity;

[0188] (g) RF microwave comprehensive tester: Integrates vector network analysis, cable and antenna feeder testing, vector voltage measurement, spectrum analysis and other functions, providing powerful comprehensive testing capabilities.

Claims

1. A test method for a flexible microwave antenna / filter, characterized in that: This method enables online testing of the microwave characteristics of flexible microwave antennas / filters during stretching, bending, torsion, and kneading processes on the same testing device. During testing, one side of the flexible microwave antenna / filter is fixed, while the other side is clamped onto the fixture of a four-degree-of-freedom (XYZθ) moving stage. The motion of each of the four degrees of freedom (X, Y, Z, θ) is independently adjustable. By controlling the individual or combined motion of these four degrees of freedom, the flexible microwave antenna / filter can be stretched, bent, twisted, and crumpled. A microwave testing instrument is connected online to the flexible microwave antenna / filter, enabling online testing of its microwave characteristics during stretching, bending, twisting, and crumpling processes on the same testing device. This includes: (1) Tensile test: The X-axis drive block of the XYZθ four-degree-of-freedom moving stage is controlled to apply a periodically changing tensile force to simulate tensile deformation, and the performance changes of the antenna and filter are monitored in real time using microwave testing instruments. (2) Bending test: The bending deformation was simulated by controlling the X-axis direction drive block of the XYZθ four-degree-of-freedom moving stage to perform periodic displacement changes, and the changes in microwave characteristics were recorded. (3) Torsion test: The torsion deformation is simulated by controlling the Y-axis drive block to make periodic displacement changes and test the microwave characteristics; the X-axis, Z-axis or θ-direction drive block can also be controlled to make periodic displacement changes to simulate torsion deformation. (4) Kneading test: The driving block is periodically displaced by controlling the Y-axis and Z-axis directions to simulate kneading deformation and perform microwave characteristic test; The testing method specifically includes the following steps: (1) Fix the opposite two edges of the manufactured flexible microwave antenna / filter to the left and right clamps respectively. The left clamp is fixed to the vertical support plate on the left, and the right clamp is fixed to the vertical XYZθ four-degree-of-freedom moving stage on the right. In the initial state, the fixing points of the left and right clamps of the XYZθ four-degree-of-freedom moving stage face each other and the clamping surfaces are in the same plane. The movement of each degree of freedom of the XYZθ four-degree-of-freedom moving stage is driven by a motor. The left and right clamps also have gold fingers and a signal interface of a microwave test instrument electrically connected to the gold fingers. The gold fingers are used to electrically connect the flexible microwave antenna / filter to the microwave test instrument. When the flexible microwave antenna / filter is clamped by the fixture, its signal input and output terminals are pressed against the gold fingers; (2) Drive the XYZθ four-degree-of-freedom moving stage so that the flexible microwave antenna / filter is stretched, bent, twisted, and crumpled respectively. While being stretched, bent, twisted, and crumpled, the microwave testing instrument tests the microwave characteristics of the flexible microwave antenna / filter and records the data; the specific implementation is as follows: (2-1) Tensile Test: Input the control signal of the XYZθ four-degree-of-freedom moving stage, drive the X-axis drive block of the XYZθ four-degree-of-freedom moving stage to gradually increase the tension to a preset value in the direction away from the right-side fixed clamp, and then gradually return to zero. The equation of the tension applied by the X-axis drive block is: , where F max The maximum tension is set to the preset value, t is the time, n is the parameter, and X, Y, Z, and θ remain unchanged. The flexible microwave antenna / filter under test is gradually stretched to the preset value and then gradually returns to zero. During the stretching process, the microwave testing instrument continuously tests and records the data. This operation is repeated a preset number of times, 1000 times, 2000 times, 5000 times, or 10000 times. (2-2) Bending Test: Input the control signal of the XYZθ four-degree-of-freedom moving stage to drive the X-axis drive block of the XYZθ four-degree-of-freedom moving stage. The motion equation of the X-axis drive block is as follows: Where A is the preset maximum displacement in the X-axis direction, t is time, n is a parameter, and Y, Z, and θ remain unchanged, so that the flexible microwave antenna / filter under test gradually bends to the preset curvature and then gradually returns to the straight state. During the bending process, the microwave testing instrument continuously tests and records data, and the operation is repeated a preset number of times, 1000 times, 2000 times, 5000 times, or 10000 times. (2-3) Twist test: Input the control signal of the XYZθ four-degree-of-freedom moving stage to drive the Y-axis driving block of the XYZθ four-degree-of-freedom moving stage. The motion equation of the Y-axis driving block is: where B is the preset maximum displacement in the Y-axis direction, t is time, m is a parameter, X and Z remain unchanged, and θ remains unchanged or changes at a preset fixed period, so that the flexible microwave antenna / filter under test is repeatedly twisted. During the twisting process, the microwave testing instrument continuously tests and records data, and the operation is repeated a preset number of times, 1000 times, 2000 times, 5000 times, or 10000 times. (2-4) Kneading Test: Input the control signal of the XYZθ four-degree-of-freedom moving stage to drive the Y-axis drive block and Z-axis drive block of the XYZθ four-degree-of-freedom moving stage. The motion equation of the Y-axis drive block is as follows: Where B is the preset maximum displacement in the Y-axis direction, and the motion equation of the driving block in the Z-axis direction is: Where C is the preset maximum displacement in the Z-axis direction, t is time, m and p are parameters, θ remains constant or changes with a preset fixed period; X is fixed at D, so that when the Y-axis driving block and the Z-axis driving block are in the initial position, the distance between the left and right clamps is less than half the length of the flexible microwave antenna / filter being tested; after the Y-axis driving block and the Z-axis driving block start moving, the flexible microwave antenna / filter is repeatedly rubbed. During the rubbing process, the microwave testing instrument continuously tests and records data, and the operation is repeated a preset number of times, 1000 times, 2000 times, 5000 times, or 10000 times; Here, steps (2-1), (2-2), (2-3), and (2-4) are not in any particular order; In steps (2-1), (2-2), (2-3), and (2-4), if the flexible microwave antenna / filter shows signs of tearing, damage, or wear, or if the microwave characteristic parameters obtained by the microwave testing instrument deviate from the preset tolerance value of the design value, the test will be terminated immediately and proceed to step (3). (3) Evaluate the tensile, bending, torsion and rubbing resistance of the flexible microwave antenna / filter based on the test data obtained in step (2).

2. The testing method for a flexible microwave antenna / filter as described in claim 1, characterized in that: In steps (2-4), m≠p. Thus, the Y-axis drive block and the Z-axis drive block drive the right clamp to move in a Liszaru curve in the vertical plane, causing the flexible microwave antenna / filter to be repeatedly kneaded. Between 3 and 10, or Between 3 and 10; or Both are decimals, meaning m and p are not integers.

3. The testing method for a flexible microwave antenna / filter as described in claim 1, characterized in that: In step (2-4), X is fixed to D, so that when the Y-axis drive block and the Z-axis drive block are in their initial positions, the distance between the left and right clamps is less than 1 / 5 of the length of the flexible microwave antenna / filter being tested.

4. The testing method for a flexible microwave antenna / filter as described in claim 1, characterized in that: In step (2-1), if the flexible microwave antenna / filter is torn or damaged, the test should be stopped immediately, and the test data before the flexible microwave antenna / filter is torn or damaged should be recorded.

5. The testing method for a flexible microwave antenna / filter as described in claim 1, characterized in that: In step (2-2), A is half the length of the flexible microwave antenna / filter being tested.

6. The testing method for a flexible microwave antenna / filter as described in claim 1, characterized in that: In step (2-3), the period of θ change is the same as the period of the Y-axis drive block.

7. A test method for a flexible microwave antenna / filter as described in any one of claims 1-6, characterized in that: The gold fingers of the left and right clamps are electrically connected to the interface of the microwave testing instrument using a flexible coaxial cable. The coaxial cable is kept slack to ensure that it will not be stretched taut during the stretching, bending, twisting, and rubbing of the flexible microwave antenna / filter.

8. The testing method for a flexible microwave antenna / filter as described in claim 7, characterized in that: For flexible microwave filters, one or more of the following microwave characteristics are tested during stretching, bending, twisting, and rubbing: Frequency response: Test the filter's response at different frequencies, including its performance in the passband and stopband; Insertion loss: measures the degree of signal attenuation as it passes through a filter; Return loss: represents the loss of the reflected signal at the input of the filter; Isolation: The degree of isolation between different signal paths in a test filter; Standing Wave Ratio (VSWR): Tests the impedance matching degree between the filter and other parts of the system; For flexible microwave antennas, one or more of the following microwave characteristics are tested during stretching, bending, twisting, and rubbing: Operating frequency: Test whether the operating frequency range of the antenna meets the design requirements; Gain: Tests the antenna's radiation or reception capability; Radiation patterns: including the morphology of the main lobe and side lobes, and their relative intensities; Impedance matching: Test whether the impedance at the antenna input terminal matches the system impedance; Polarization characteristics: Test the polarization mode and performance of the antenna; Directivity: Tests the directionality of the antenna's radiated or received signals.

9. The testing method for a flexible microwave antenna / filter as described in claim 8, characterized in that: Microwave testing instruments employ one or more combinations of the following devices to meet different testing needs and standards: (a) Vector Network Analyzer (VNA): Used to measure network parameters such as VSWR, return loss, and insertion loss; (b) Spectrum analyzer: used to measure the spectral characteristics of a signal, such as frequency range and power distribution; (c) Microwave anechoic chamber: provides a reflection-free testing environment for measuring antenna patterns and analyzing radiation characteristics; (d) Signal generator: used to generate test signals to simulate the signal environment under actual working conditions; (e) Power meter: used to measure the power level of a signal; (f) Antenna test system: including turntable, polarizer, and RF amplifier, used for comprehensive testing of antenna performance, such as gain, polarization characteristics, and directivity; (g) Radio Frequency Microwave Integrated Tester: It integrates multiple functions such as vector network analysis, cable and antenna feeder testing, vector voltage measurement, and spectrum analysis, providing powerful comprehensive testing capabilities.

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