A high-sensitivity tangential electric field measurement probe with adjustable resonance frequency

Abstract

The invention discloses a high-sensitivity tangential electric field measurement probe with adjustable resonant frequency, comprising a tangential electric field sensing front end portion composed of a pair of bent dipole units, and a resonant frequency transmission portion for improving the test sensitivity of the probe, wherein the resonant frequency transmission section is composed of coupled strip lines to form a resonant transmission characteristic, and a pair of variable capacitance diodes are introduced simultaneously in two sections of the transmission line, thereby realizing the transmission characteristic of adjustable resonant frequency, and the other part is a differential mode to common mode transmission portion composed of a balun structure, which realizes the conversion of the signal from a balanced mode to an unbalanced mode, and the last part is a coplanar waveguide transmission structure, which finally realizes the acquisition from the induced field signal to the output signal, wherein the top and bottom surfaces of the probe are metal shielding layers. The invention adopts an external bias voltage to regulate the capacitance of the variable capacitance diode, thereby realizing the adjustable resonant frequency characteristic of the probe transmission portion, so as to realize the dynamic regulation of the resonant frequency of the tangential electric field probe.

Description

Technical Field

[0001] The present invention belongs to the technical field of microwave measurement devices, and specifically relates to a high-sensitivity tangential electric field measurement probe with adjustable resonant frequency, which can obtain the tangential electric field component of the electromagnetic field within the working frequency band under high sensitivity conditions, thereby analyzing electromagnetic compatibility and electromagnetic radiation problems. Background Art

[0002] In recent years, with the rapid development of modern consumer electronic products and various electronic devices, the electromagnetic field environment inside electronic products and devices and the radiation generated by consumer electronic products have also received extensive research and attention. The distribution between the functional modules and devices inside current consumer electronic products is very compact, and the electromagnetic compatibility problems between the modules are becoming increasingly prominent. In order to analyze and solve the electromagnetic compatibility problems inside electronic products, the electromagnetic compatibility problems can be analyzed by studying the internal electromagnetic field distribution. At the same time, with the increasing improvement of living standards and the popularization of consumer electronic products, the impact of electronic products on people's health has also received more and more attention and attention. Among them, the radiation generated by electronic products is the most closely affecting factor on human health. In order to study the radiation impact of electronic products on the human body, it is necessary to study and analyze the electromagnetic field distribution generated by electronic products when they are working. Therefore, whether it is to solve the electromagnetic compatibility problems of consumer electronic products or to analyze the impact of electronic product radiation on the human body, obtaining and analyzing its electromagnetic field distribution is of great research significance and application value.

[0003] Being able to obtain accurate electromagnetic field distribution and establish a suitable electromagnetic model is the key to analyzing electromagnetic compatibility and electromagnetic radiation issues. The near-field probe can effectively measure and obtain the electromagnetic field distribution within the near-field range. It can be used to study the characteristics of materials in the microwave frequency band, detect the electromagnetic field coupling relationship on the surface of the device, and locate the noise source of the device functional module. By using the near-field measurement probe to perform near-field scanning at a preset distribution position in the plane to be measured, the electromagnetic field distribution in the entire plane can be obtained, thereby evaluating electromagnetic compatibility and electromagnetic radiation issues. In the process of near-field scanning detection, the probe used is generally a broadband electric field or magnetic field measurement probe. The advantage of this probe is that it can effectively measure the electric field or magnetic field in a specific frequency band and obtain the electromagnetic field distribution at any frequency point within the working bandwidth of the probe. However, in scenarios where the electromagnetic field to be detected is extremely weak or the electromagnetic noise source to be located is difficult to measure, this broadband probe is difficult to achieve a good measurement effect. Therefore, improving the sensitivity of the measurement probe and designing a highly sensitive electromagnetic field probe are of great application value and research significance.

[0004] At present, in order to obtain a highly sensitive electromagnetic field probe, the solutions that can be adopted mainly include structural design in the sensing part of the probe, thereby increasing the front-end equivalent sensing area of ​​the probe to obtain more electromagnetic field energy; or designing an active electromagnetic field probe, designing an amplification circuit inside the probe to amplify the detection signal; in addition, designing a resonant structure inside the probe can obtain higher sensitivity at the desired frequency point. For consumer electronic products such as mobile phones, their operating frequency bands are relatively narrow. In order to locate electromagnetic noise or measure electromagnetic radiation within this operating frequency band, a resonant electromagnetic field probe can be used to obtain a higher detection sensitivity. Nowadays, researchers have made corresponding studies on resonant electric field or magnetic field probes, but the designed resonant probes are all probes that work at a single frequency point, and can only perform high-sensitivity measurements on fixed frequencies. When it is necessary to conduct electromagnetic compatibility and electromagnetic radiation research and analysis on other frequencies, it is necessary to redesign the resonant structure of the probe, or even change the overall structural parameters. Therefore, designing a probe with adjustable resonant frequency can easily obtain high-sensitivity measurement results when detecting electromagnetic fields within a certain frequency band. Nowadays, consumer electronic products are developing rapidly. Designing a high-sensitivity tangential electric field measurement probe with adjustable resonant frequency is helpful to extract the tangential electric field component, thereby facilitating the research and analysis of electromagnetic compatibility and electromagnetic radiation issues. Summary of the invention

[0005] Technical problem: In order to solve the problems existing in the prior art, the present invention provides a high-sensitivity tangential electric field measurement probe with adjustable resonant frequency, which has the advantages of simple structural design and dynamic adjustability, and can adjust the resonant frequency of the probe by adjusting the bias voltage, thereby obtaining high-sensitivity tangential electric field measurement, so as to facilitate the study of electromagnetic radiation and electromagnetic compatibility issues.

[0006] Technical solution: The lower part of a high-sensitivity tangential electric field measuring probe with adjustable resonant frequency of the present invention is a tangential electric field sensing part composed of a pair of bent dipole units, the upper part of the bent dipole unit is a stripline coupled resonant transmission part, the upper part of the stripline coupled resonant transmission part is a differential mode to common mode balun transmission structure, the upper part of the balun transmission structure is a coplanar waveguide transmission part, the two sides outside the stripline coupled resonant transmission part and the balun transmission structure are multi-layer metallized through holes, and the two sides outside the multi-layer metallized through holes are metal shielding sides; the tangential electric field measuring probe is composed of five stacked dielectric layers, and the two sides of the first and fifth dielectric layers are coated with metal layer structures;

[0007] The first metal layer structure of the probe is provided with a metal shielding layer and a coplanar waveguide transmission part. The second metal layer structure serves as the metal ground on the back side of the coplanar waveguide transmission part of the top layer. The third metal layer structure is cascaded with a pair of bent dipole units, a stripline coupled resonant transmission part and a differential mode to common mode balun transmission structure. The fourth metal layer structure is a metal shielding layer, as well as a varactor diode and a metal pad for adjusting the resonant frequency.

[0008] The tangential electric field measurement probe is mainly realized through the transmission characteristics of the stripline coupled resonant transmission part. The stripline coupled resonant transmission part is composed of a coupled stripline and stripline resonant branches located on both sides of the coupled stripline. Stripline resonant branches of different lengths can achieve the required resonant operating frequency.

[0009] The stripline coupled resonant transmission part is provided with a varactor diode for adjusting the resonant frequency of the stripline coupled resonant transmission part, and the varactor diode is connected between a metal pad and a metal shielding layer serving as a ground, wherein the metal pad is interconnected with the stripline resonant branch on the third metal layer structure through a metallized through-hole, and there is a certain spacing gap between the metal pad and the metal shielding layer.

[0010] The pair of bent dipole units are composed of periodically bent dipole units, the dipole units are made of metal materials, and the bent structure can increase the equivalent length of electric field induction and improve the detection sensitivity of the probe.

[0011] The differential mode to common mode balun transmission structure is composed of a power divider stripline transmission part and a 180-degree stripline phase shifter, which can convert the probe sensing signal transmitted from the stripline coupled resonant transmission part from balanced to unbalanced transmission, thereby realizing dual-port to single-port output.

[0012] The conductor part of the coplanar waveguide transmission part is on the first metal layer structure, the metal ground is on the second metal layer structure, and the conductor transmission part of the top layer is connected to the strip line of the differential mode to common mode balun transmission structure on the third metal layer through a metallized through hole.

[0013] In the five-layer dielectric structure, the first, third and fifth dielectric layers are Rogers 4350B dielectric layers, each with a thickness of 0.254 mm, and the second and fourth dielectric layers are Rogers 4450F dielectric layers, with a thickness of 0.2 mm. The first metal structure includes a coplanar waveguide transmission part, a multi-layer metallized through hole, a metal shielding layer, and a metal shielding side, wherein the multi-layer metallized through hole is arranged on both sides of the metal shielding layer, the metal shielding layer is arranged on both sides of the multi-layer metallized through hole, and the coplanar waveguide transmission part is located on the upper part of the metal shielding layer.

[0014] The second metal structure includes multiple layers of metalized through holes on both sides; the fourth metal structure includes a metal shielding layer, a metal pad, and a varactor diode.

[0015] The metal shielding layer is located at the upper part, the metal pad is located at the lower part of the metal shielding layer, and the varactor diode is located on the metal pad.

[0016] The third-layer metal structure includes a balun transmission structure located at the top and a stripline coupled resonant transmission part located at the bottom of the balun transmission structure. The stripline coupled resonant transmission part includes a coupled stripline and stripline resonant branches located on both sides of the coupled stripline. The upper end of the coupled stripline is connected to the balun transmission structure, and the lower end of the coupled stripline is connected to the bent dipole unit.

[0017] The top and bottom metal shielding layers and the metal shielding sides reduce the disturbance effect of the surrounding electromagnetic field on the internal field of the probe. The multi-layer metallized through holes on the sides connect the top and bottom metal shielding layers, which can reduce the resonance caused inside the electric field measurement probe.

[0018] Beneficial effect: Compared with the prior art, the high-sensitivity tangential electric field measurement probe with adjustable resonant frequency of the present invention has the following advantages and functions: by adjusting the external bias voltage of the probe, the tangential electric field components of different resonant operating frequencies can be obtained, thereby improving the detection sensitivity of the tangential components of the electric field to be measured. Unlike the existing high-sensitivity measurement probe with a single resonant frequency point, the high-sensitivity tangential electric field measurement probe with adjustable resonant frequency is not only limited to high-sensitivity detection of a single frequency point, but can achieve high-sensitivity detection within a frequency band bandwidth, thereby improving the detection utilization rate of the probe to a certain extent, and can also obtain high-sensitivity electric field measurement at the same time, which is suitable for the wide demand for measurement probes in electromagnetic compatibility and electromagnetic radiation, and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The printed circuit board stacking structure diagram of the tangential electric field measuring probe with high sensitivity and adjustable resonance frequency is shown in the figure.

[0020] Figure 2 It is an overall structural diagram of the high-sensitivity tangential electric field measuring probe with adjustable resonant frequency of the present invention.

[0021] Figure 3a It is a top view of the first metal structure of the tangential electric field measuring probe with high sensitivity and adjustable resonance frequency of the present invention.

[0022] Figure 3b It is a top view of the second metal structure of the tangential electric field measuring probe with high sensitivity and adjustable resonance frequency of the present invention.

[0023] Figure 3c It is a top view of the third metal structure of the tangential electric field measuring probe with high sensitivity and adjustable resonance frequency of the present invention.

[0024] Figure 3d It is a top view of the fourth metal structure of the tangential electric field measuring probe with high sensitivity and adjustable resonance frequency of the present invention.

[0025] Figure 4 It is a simulation structure diagram of the high-sensitivity tangential electric field measuring probe with adjustable resonant frequency of the present invention.

[0026] Figure 5 It is a resonant characteristic frequency curve diagram of the tangential electric field measuring probe with high sensitivity and adjustable resonant frequency of the present invention.

[0027] The figure includes: bent dipole unit 1, stripline coupled resonant transmission part 2, varactor diode 3, balun transmission structure 4, coplanar waveguide transmission part 5, multi-layer metallized through-hole 6, metal shielding layer 7, metal shielding side 8, metal pad 9, coupled stripline 10, and stripline resonant branch 11. DETAILED DESCRIPTION

[0028] In order to achieve the above-mentioned object of the invention, the specific implementation scheme of the high-sensitivity tangential electric field measurement probe with adjustable resonant frequency of the present invention is as follows:

[0029] The lower part of the electric field measurement probe is a tangential electric field sensing part composed of a pair of bent dipole units 1, the upper part of the bent dipole unit 1 is a stripline coupled resonant transmission part 2, the upper part of the stripline coupled resonant transmission part 2 is a differential mode to common mode balun transmission structure 4, the upper part of the balun transmission structure 4 is a coplanar waveguide transmission part 5, the two sides outside the stripline coupled resonant transmission part 2 and the balun transmission structure 4 are multi-layer metallized through holes 6, and the two sides outside the multi-layer metallized through holes 6 are metal shielding side edges 8; the tangential electric field measurement probe is composed of five stacked dielectric layers, and the first and fifth dielectric layers are provided with metal layer structures on both sides;

[0030] A metal shielding layer 7 and a coplanar waveguide transmission part 5 are provided on the first metal layer structure of the probe; the second metal layer structure serves as the metal ground on the back side of the coplanar waveguide transmission part 5 of the top layer; the third metal layer structure is cascaded with a pair of bent dipole units, a stripline coupled resonant transmission part 2 and a differential mode to common mode balun transmission structure 4; the fourth metal layer structure is a metal shielding layer 7, a varactor diode 3 and a metal pad 9 for adjusting the resonant frequency.

[0031] The high-sensitivity resonant frequency adjustable tangential electric field measurement probe of the present invention is composed of a bent dipole unit, a stripline coupled resonant transmission part, a varactor diode, a balun transmission structure and a coplanar waveguide transmission part. The bent dipole unit is used to improve the sensitivity of the tangential component of the electric field to a certain extent. The bent dipole unit includes two bent dipole arms, each of which has a tangential length of 7.46 mm and a vertical length of 4 mm, and the spacing between the two bent dipole arms is 0.65 mm.

[0032] The tangential electric field measurement probe is designed and processed based on a five-layer dielectric plate structure, wherein the five-layer dielectric plate structure is composed of a top layer, three middle layers and a bottom layer from top to bottom. The top layer, the third layer and the bottom layer of the five-layer dielectric plate structure are composed of Rogers 4350B plates with a thickness of 0.254 mm, and the second layer and the fourth layer are composed of Rogers 4450F plates with a thickness of 0.2 mm, wherein the Rogers 4350B plates of the top layer and the bottom layer are double-sided copper-clad plates, the third layer is a Rogers 4350B dielectric plate without copper cladding, and the Rogers 4450F dielectric plates of the second layer and the fourth layer are used as prepregs in the multi-layer plate structure, which is convenient for the processing of the stacked structure.

[0033] The stripline coupled resonant transmission part is to produce resonant transmission characteristics, thereby improving the detection sensitivity of the corresponding resonant frequency and obtaining a higher received signal strength. The stripline coupled resonant transmission part is on the upper surface of the fifth dielectric layer and consists of two identical resonant transmission structures, which are respectively connected to two bent dipole arms, wherein the resonant transmission structure consists of a discontinuous stripline transmission line and two coupling branches, the length of the coupling branches can change the resonant transmission frequency, and the stripline and coupling branches are made of metallic copper, and their widths are both 0.41 mm. The varactor diode is connected between the coupling branch and the metal ground. According to the adjustable range of different frequency bands, varactor diodes with different capacitance adjustment ranges can be selected. In order to achieve the effect of adjustable resonant frequency of the probe, the present invention adopts a varactor diode with model SMV2204-040LF produced by Skyworks, and its capacitance adjustment range can be from 0.61 to 7.17PF. There is a metal pad on the bottom surface of the probe, and there is a certain spacing distance between the metal pad and the metal shielding layer. The metalized via is connected to the coupling branch, and the varactor diode is connected between the metal pad and the bottom metal shielding layer. The bottom metal shielding layer plays the role of a metal ground, so different resonant transmission frequencies can be obtained by changing different varactor diode capacitances.

[0034] The balun transmission structure is to convert the balanced signal sensed by the bent dipole unit into an unbalanced signal for reception. The two transmission line parts of the balun introduce a 180-degree phase difference, thereby converting the sensed differential mode voltage into a common mode voltage to obtain two equal amplitude and in-phase transmission signals. The balun transmission structure is processed with metal copper material on the upper surface of the bottom dielectric plate and integrated inside the dielectric interlayer of the probe.

[0035] The coplanar waveguide transmission part transmits the common mode voltage signal transmitted through the internal balun to the external signal interface, so that it is received and processed by the back-end test instrument. The coplanar waveguide transmission part is composed of a coplanar waveguide transmission line with a metal backplane, wherein the back metal ground of the coplanar waveguide is located on the lower surface of the top dielectric layer, and the transmission conductor part of the coplanar waveguide is located on the top metal layer, with a line width of 0.44mm and a characteristic impedance of 50Ω.

[0036] The specific structure of the tangential electric field measuring probe with high sensitivity and adjustable resonance frequency, the positional relationship of each structural part and the function of each part of the present invention will be further explained below in conjunction with the accompanying drawings.

[0037] Figure 1 The printed circuit board stacking structure diagram of the high-sensitivity resonant frequency adjustable tangential electric field measuring probe of the present invention is shown. The stacking structure is a five-layer dielectric plate structure, wherein the first layer, the third layer and the fifth layer are composed of Rogers 4350B dielectric plates with a thickness of 0.254 mm, the second layer and the fourth layer are composed of Rogers 4450F dielectric plates with a thickness of 0.2 mm, and the first layer and the fifth layer are Rogers 4450B dielectric plates with double-sided copper cladding, and the third layer is Rogers 4450B dielectric plates without copper cladding. Rogers 4450F dielectric plates serve as prepregs in the multi-layer plate structure, which facilitates the processing of the dielectric stacking structure.

[0038] Figure 2The overall structure diagram of a high-sensitivity tangential electric field measurement probe with adjustable resonant frequency described in the present invention is shown. The structures from bottom to top are: bent dipole unit 1, stripline coupled resonant transmission part 2, varactor diode 3, metal pad 9, balun transmission structure 4, coplanar waveguide transmission part 5, SMA connector. The sensing part of the probe includes two bent dipole arms, each of which has a tangential length of 7.46 mm and a vertical length of 4 mm. The spacing between the two bent dipole arms is 0.65 mm. The function of the bent dipole unit is to improve the inductive sensitivity to the tangential component of the electric field. The bent dipole arm is connected to the stripline coupled resonant transmission part to generate a resonant transmission characteristic. The coupled resonant transmission part is composed of a discontinuous stripline transmission line and two stripline coupled branches, wherein the width of the stripline transmission line and the coupled branches are both 0.41 mm. The stripline coupled resonant transmission part is connected to the balun transmission structure. The balun transmission structure converts two balanced signals into an unbalanced signal for common transmission by introducing a 180-degree phase shift. The connection part from the bent dipole unit to the balun transmission structure is as follows: Figure 3c shown. Figure 3a The figure shows that the coplanar waveguide transmission part is connected to the balun transmission structure. The center conductor and the upper surface metal ground of the coplanar waveguide are both on the first metal layer structure. The coplanar waveguide transmission part here is a coplanar waveguide with back metal. The back metal ground is located on the second metal layer structure. The characteristic impedance of the coplanar waveguide is 50Ω, as shown in FIG. Figure 3b shown. Figure 3d It shows that the stripline coupled resonant branches are connected to the underlying metal pads through metalized vias, such as Figure 3d As shown in the enlarged view in Figure 2, the SMV 2204-040LF varactor diode is connected between the metal pad and the metal shield layer, which plays the role of adjusting the capacitance and thus changing the resonant frequency of the probe.

[0039] In order to analyze the performance of the high-sensitivity tangential electric field measurement probe with adjustable resonant frequency, the transmission performance of the probe was simulated. The specific simulation structure diagram is shown in Figure 4 As shown, the probe is used to detect a section of microstrip line, the receiving port of the probe is port 1, and the two transmission ports of the microstrip line are port 2 and port 3. Figure 5 The resonance characteristic frequency curve of a high-sensitivity tangential electric field measurement probe with adjustable resonant frequency is shown. By adjusting the external bias voltage, the capacitance value of the variable capacitance diode is changed, and the resonant frequency of the probe can be changed to obtain high-sensitivity detection at different measurement frequencies. The capacitance of the variable capacitance diode used in this embodiment can be adjusted from 0.61pF to 7.17pF. Within the range of continuous adjustment of the capacitance, the probe can achieve high-sensitivity tangential electric field measurement in the frequency range from 1.74GHz to 2.50GHz.

[0040] It should be pointed out that it should be understood that these embodiments of the present invention are only used to illustrate the present invention and are not used to limit the scope of the present invention. After reading the present invention, various equivalent modifications of the present invention by those skilled in the art all fall within the scope defined by the claims attached to this application.

Claims

1. A high-sensitivity tangential electric field measurement probe with adjustable resonant frequency, characterized in that: The lower part of the electric field measurement probe is a tangential electric field sensing part composed of a pair of bent dipole units (1); the upper part of the bent dipole unit (1) is a stripline coupled resonant transmission part (2); the upper part of the stripline coupled resonant transmission part (2) is a differential mode to common mode balun transmission structure (4); the upper part of the balun transmission structure (4) is a coplanar waveguide transmission part (5); the two sides outside the stripline coupled resonant transmission part (2) and the balun transmission structure (4) are multi-layer metallized through holes (6); the two sides outside the multi-layer metallized through holes (6) are metal shielding side edges (8); the tangential electric field measurement probe is composed of five stacked dielectric layers, and metal layer structures are applied on both sides of the first and fifth dielectric layers; A metal shielding layer (7) and a coplanar waveguide transmission part (5) are provided on the first metal layer structure of the probe, the second metal layer structure serves as the metal ground on the back side of the coplanar waveguide transmission part (5) of the top layer, the third metal layer structure is formed by cascading a pair of bent dipole units, a stripline coupled resonant transmission part (2) and a differential mode to common mode balun transmission structure (4), and the fourth metal layer structure is a metal shielding layer (7), a varactor diode (3) and a metal pad (9) for adjusting the resonant frequency; The stripline coupled resonant transmission part (2) is provided with a variable capacitance diode (3) for adjusting the resonant frequency of the stripline coupled resonant transmission part (2), and the variable capacitance diode (3) is connected between a metal pad (9) and a metal shielding layer (7) serving as a ground, wherein the metal pad (9) is interconnected with a stripline resonant branch (11) on the third metal layer structure through a metallized through hole, and a certain gap is provided between the metal pad (9) and the metal shielding layer (7).

2. The high-sensitivity tangential electric field measuring probe with adjustable resonance frequency according to claim 1, characterized in that: The tangential electric field measurement probe is realized by the transmission characteristics of the stripline coupled resonant transmission part (2). The stripline coupled resonant transmission part (2) is composed of a coupled stripline (10) and stripline resonant branches (11) located on both sides of the coupled stripline (10). Stripline resonant branches (11) of different lengths can achieve the required resonant operating frequency.

3. The high-sensitivity tangential electric field measurement probe with adjustable resonance frequency according to claim 1, characterized in that: The pair of bent dipole units (1) are composed of periodically bent dipole units, the dipole units are made of metal material, and the bent structure can increase the equivalent length of electric field induction and improve the detection sensitivity of the probe.

4. The high-sensitivity tangential electric field measuring probe with adjustable resonance frequency according to claim 1, characterized in that: The differential mode to common mode balun transmission structure (4) is composed of a power divider stripline transmission part and a 180-degree stripline phase shifter, and can convert the probe sensing signal transmitted from the stripline coupled resonant transmission part (2) from balanced to unbalanced transmission, thereby realizing dual-port to single-port output.

5. The high-sensitivity tangential electric field measurement probe with adjustable resonance frequency according to claim 1, characterized in that: The conductor part of the coplanar waveguide transmission part (5) is on the first metal layer structure, the metal ground is on the second metal layer structure, and the conductor transmission part of the top layer is connected to the strip line of the differential mode to common mode balun transmission structure (4) of the third metal layer through a metallized through hole.

6. The high-sensitivity tangential electric field measurement probe with adjustable resonance frequency according to claim 1, characterized in that: In the five-layer dielectric structure, the first, third and fifth dielectric layers are Rogers 4350B dielectric layers, each with a thickness of 0.254 mm, and the second and fourth dielectric layers are Rogers 4450F dielectric layers, each with a thickness of 0.2 mm.

7. The high-sensitivity tangential electric field measurement probe with adjustable resonance frequency according to claim 1, characterized in that: The first metal layer structure comprises a coplanar waveguide transmission portion (5), a multi-layer metallized through hole (6), a metal shielding layer (7), and a metal shielding side (8), wherein the multi-layer metallized through hole (6) is arranged on both sides of the metal shielding layer (7), the metal shielding layer (7) is arranged on both sides of the multi-layer metallized through hole (6), and the coplanar waveguide transmission portion (5) is located on the upper part of the metal shielding layer (7).

8. The high-sensitivity tangential electric field measurement probe with adjustable resonance frequency according to claim 1, characterized in that: The second metal layer structure comprises a multi-layer metallized through hole (6) located on both sides; the fourth metal layer structure comprises a metal shielding layer (7), a metal pad (9), and a varactor diode (3), The metal shielding layer (7) is located at the upper part, the metal pad (9) is located at the lower part of the metal shielding layer (7), and the varactor diode (3) is located on the metal pad (9).

9. The high-sensitivity tangential electric field measurement probe with adjustable resonance frequency according to claim 1, characterized in that: The third metal layer structure comprises a balun transmission structure (4) located at the top and a stripline coupled resonant transmission part (2) located at the bottom of the balun transmission structure (4); the stripline coupled resonant transmission part (2) comprises a coupled stripline (10) and stripline resonant branches (11) located at both sides of the coupled stripline (10); the upper end of the coupled stripline (10) is connected to the balun transmission structure (4); and the lower end of the coupled stripline (10) is connected to the bent dipole unit (1).

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