Near-field shaped antenna for electromagnetic compatibility testing

Abstract

The near-field shaped antenna for electromagnetic compatibility testing mainly includes a ground plate frame (1), a plate (2) and a connector (3); the plate (2) is perpendicular to the ground plate (10) of the ground plate frame (1), and the plate (2) and the ground plate (10) form two poles of the antenna; the length of the vertical projection (20) of the plate (2) on the plane where the ground plate (10) is located is greater than one-third of the maximum working wavelength; the radiation edge (21) of the plate (2) is in the shape of a gradually opening curve; the notch (24) extends into the interior of the plate (2) to form an additional oscillator (25). The antenna is small in size, light in weight, and flexible in movement. It is not only easy to use, but also reduces the requirement for test transmission power, reduces the cost of the test device and the test operation cost, improves the vertical polarization radiation field, improves the uniformity of the test field strength, and improves the repeatability and reproducibility of the test.

Description

Technical Field

[0001] The invention relates to electromagnetic compatibility testing, in particular to a near-field shaped antenna for electromagnetic compatibility testing. Background Art

[0002] The purpose of electromagnetic compatibility testing is to verify the sensitivity of the electrical and electronic products or systems under test (collectively referred to as the DUT) to external electromagnetic fields. During testing, the transmitting antenna is required to generate an electromagnetic field in the DUT's area with a frequency that meets the test standard and a field strength and amplitude that meet the required uniformity. According to the test standard ISO 11451-2 (Road vehicles—Test methods for immunity to narrowband radiated electromagnetic energy—Part 2: External radiated sources), the operating frequency range of the field generator (transmitting antenna) used in the test is 20 MHz to 18 GHz.

[0003] At a frequency of 20 MHz, the wavelength is 15 meters. The test area is actually the antenna's near zone, and the electromagnetic field in the test area is the near field. The near-field electromagnetic field includes not only radiation fields but also induction fields. However, existing antennas used for EMC testing use beamforming based on far-field radiation fields, failing to consider the impact of near-field induction fields on the electromagnetic field in the test area. Sometimes, only standing waves are considered.

[0004] When the test operating frequency is relatively high, the antenna size is small, and a relatively wide range of antenna types are available. However, at lower operating frequencies, particularly in the 20MHz to 220MHz frequency range, the available antenna size is quite large. The logarithmic periodic broadband antennas commonly used in EMC testing, while theoretically capable of operating in any frequency band and with an arbitrarily wide operating bandwidth, are limited by practical operating environments and often fail to meet theoretical performance. The lowest operating frequency of a typical broadband logarithmic periodic antenna is 80MHz. Using a larger broadband logarithmic periodic antenna would allow the lowest operating frequency to reach 20MHz, but the logarithmic periodic antenna's oscillator would be large, requiring it to be mounted at a high height, often significantly higher than the DUT. Due to anechoic chamber space limitations and to ensure sufficient test field strength within the DUT's test area, the DUT must be located close to the transmitting antenna. When the test antenna is mounted high, even though the antenna's main lobe is parallel to the ground, if the DUT is located on the ground and very close to the antenna, the DUT's test area may not be within the transmitting antenna's main lobe, resulting in a decrease in radiated power density. Placing the log-periodic broadband antenna farther from the DUT could avoid this problem, but this approach is not always feasible due to the limited space of the anechoic chamber. Furthermore, the distance reduces the radiated power density in the DUT's test area. Furthermore, the antenna's high position means that the ground-reflected waves from the antenna overlap with the direct waves from the antenna in the DUT's test area, resulting in uneven field strength across the test area. This impacts the adequacy of the test, the repeatability of the test results, and ultimately the accuracy of the test.

[0005] On the other hand, the two dipole arms (plates) of the log-periodic antenna are placed relative to each other, making the antenna relatively large. A metal ground plate is also used to replace one of the dipole arms, but the ground plate is usually required to be very large, which not only makes the antenna unable to move but also affects the flexibility of antenna placement.

[0006] Typically, to reduce the size of the antenna, slots are cut into the antenna to extend the current flow path, thereby lowering the antenna's operating frequency. However, these antennas do not have a shaping effect on the electromagnetic field in the test area. Although they can meet the standing wave requirements of the antenna at low frequencies, because the current path is not designed according to the requirements of the electromagnetic field power density, the currents in different parts of the path cancel each other out in the electromagnetic field of the test area, resulting in low antenna gain. Unreasonable current paths can also lead to the generation of many non-vertically polarized electromagnetic fields, such as horizontally polarized electromagnetic fields. Although these non-vertically polarized electromagnetic fields contribute to the electromagnetic wave power density and gain, due to the negative mirror effect of the ground on the horizontal polarization, they are usually relatively weak near the test piece. These non-vertically polarized electromagnetic fields do not contribute to the test. Summary of the Invention

[0007] Technical problem: The present invention proposes a near-field shaping antenna for electromagnetic compatibility testing, which can shape the beam and polarization of the electromagnetic field in the test area, improve and enhance the intensity of the vertically polarized electromagnetic field in the test area, and solve the problem of large antenna size, and can ensure that the antenna has good standing wave performance at low frequency and wide bandwidth; in addition, the required ground plate size is small, and there is no feed matching network or balun; the antenna height is low, which reduces the adverse effects of ground reflection on the field strength uniformity of the test area of ​​the test piece, and also allows the test piece located on the ground to always be located in the main beam of the antenna.

[0008] Technical solution:

[0009] The near-field shaped antenna for electromagnetic compatibility testing of the present invention is characterized in that the antenna includes a ground plate frame, a pole plate and a connector; the ground plate frame includes a ground plate and a plurality of guide wheels; the ground plate and the pole plate are made of materials with good conductive properties; the pole plate is perpendicular to the ground plate, and the pole plate and the ground plate constitute the two poles of the antenna; at the input end of the antenna, the inner conductor of the connector is connected to the pole plate, and the outer conductor of the connector is connected to the ground plate; the length of the vertical projection of the pole plate on the plane where the ground plate is located is less than one-third of the maximum working wavelength; the pole plate includes an input end edge, a radiation edge, a proximal vertical edge, a proximal concave edge, The proximal oblique edge, the distal vertical edge, the first upper edge, the second upper edge and the notch; near the input end of the antenna, the plate has an input end edge, which is a straight line and parallel to the ground plate; one end of the input end edge is connected to the proximal vertical edge near the joint, and the other end of the input end edge is connected to the radiation edge; the radiation edge shape is a curve; the end of the radiation edge closest to the ground plate is connected to the input end edge, and the other end of the radiation edge is connected to the distal vertical edge; the distance from the radiation edge to the ground plate is gradual, and at the point where the radiation edge is connected to the input end edge, the radiation edge to the ground plate is gradually connected. The distance to the ground plane is the shortest, and the distance from the radiating edge to the ground plane is the largest at the point where the radiating edge is connected to the distal vertical edge; the distance from the radiating edge to the ground plane becomes larger and larger from the point where the radiating edge is connected to the input end edge to the point where the radiating edge is connected to the distal vertical edge; the proximal vertical edge is perpendicular to the ground plane, one end of the proximal vertical edge is connected to the input end edge, and the other end is connected to the proximal oblique edge, with a proximal concave edge between the two ends; the distal vertical edge is a straight line, which is perpendicular to the ground plane, the proximal end of the distal vertical edge is connected to the radiating edge, and the distal end of the distal vertical edge is connected to the radiating edge. The end is connected to the second upper edge; the shape of the proximal oblique edge is a straight line; one end of the proximal oblique edge is connected to the proximal vertical edge and the other end is connected to the first upper edge; the vertical projection of the connection point of the proximal oblique edge and the first upper edge on the plane where the grounding plate is located is located between the vertical projection of the proximal vertical edge on the plane where the grounding plate is located and the vertical projection of the distal vertical edge on the plane where the grounding plate is located; there is a notch between the first upper edge and the second upper edge, and the notch extends into the interior of the electrode, so that an additional vibrator is formed on the upper part of the electrode; the surface of the grounding plate is a plane, and when working, the grounding plate is electrically contacted with the ground.

[0010] At the notch, the edge of the plate includes a first arcuate edge, a second arcuate edge and a straight edge; one end of the first arcuate edge is connected to the first upper edge, and the other end is connected to the second arcuate edge, and the internal angle between the first arcuate edge and the first upper edge is less than degrees; one end of the second arcuate edge is connected to the first arcuate edge, and the other end is connected to the straight edge, and the internal angle between the second arcuate edge and the first arcuate edge is an acute angle; one end of the straight edge is connected to the second arcuate edge, and the other end is connected to the second upper edge, the internal angle between the straight edge and the second arcuate edge is an acute angle, and the internal angle between the straight edge and the second upper edge is an obtuse angle; the size of the proximal concave edge is changed so that the radiation field of the antenna is maximized in the test area of ​​the test piece.

[0011] The additional vibrator consists of a proximal oblique edge, a first upper edge and a first arc-shaped edge; according to the requirement of maximizing the vertical polarization radiation field, the angle between the proximal oblique edge and the grounding plate, the shape and size of the first arc-shaped edge, and the distance and length from the first upper edge to the grounding plate are determined.

[0012] The guide wheel is flippable. When working, the guide wheel flips over to the top of the ground plate so that the ground plate maintains electrical contact with the ground of the test chamber; when moving, the guide wheel flips under the ground plate to facilitate the movement of the entire antenna.

[0013] At the antenna input, the distance from the input edge to the ground plane makes the characteristic impedance at this location 50 ohms.

[0014] The shape of the radiation edge can be determined according to the matching requirements within the operating frequency band.

[0015] The guide wheel makes the antenna easy to move, allowing it to be moved to the optimal test position, greatly facilitating testing. During operation, the guide wheel flips over the ground plate, ensuring electrical contact between the ground plate and the test chamber. This fully utilizes the entire chamber floor as another plate for the antenna, allowing a smaller ground plate area to achieve the effect of a larger ground plate. While maintaining antenna radiation performance, the antenna height is reduced. This allows the antenna to be very close to the test device, minimizing distance attenuation and reducing the test transmission power requirement. Furthermore, when the antenna is very close to the test device on the ground, the test device is always within the antenna's main lobe.

[0016] When the antenna operates in the low-frequency band, the test area is located in the near-zone of the antenna, where two primary radiating elements are active. One is the main radiating element, consisting of a radiating edge, a distal vertical edge, a second upper edge, a straight edge, a second curved edge, and a portion of the first curved edge; the other radiating element is an additional dipole. The field strength in the test area is the sum of the field strengths of these two radiating elements in the near-zone. Because the near-zone field includes not only radiation but also induction, the design of this superposition is much more complex than that of the far-zone field. Detailed design requires simulation tools to shape the electromagnetic field in the test area. By varying the size of the proximal concave edge and its position relative to the proximal vertical edge, the relative amplitude and phase of the currents in the two radiating elements can be adjusted to maximize the power density in the test area. By varying the length of the proximal bevel edge, its angle with the ground plane, and the shape of the first curved edge, the radiation intensity of the additional dipole can be adjusted while also maximizing the vertically polarized radiation field in the test area. When the antenna operates in the high-frequency band, the test area is located in the far-zone of the antenna, and the main radiating element plays a primary role.

[0017] The plate is fixed with a support frame, and the support frame is made of non-metallic materials to avoid affecting the performance of the antenna.

[0018] Beneficial effects: The beneficial effects of the present invention are: the proposed near-field shaping antenna for electromagnetic compatibility testing shapes the beam and polarization of the electromagnetic field in the test area, improves and enhances the intensity of the vertically polarized electromagnetic field in the test area, and is not only small in size, but also has good standing wave performance at low frequencies and wide bandwidths; the ground plate is small in size, the antenna is easy to move, the antenna is light in weight, and the installation position is low, which is not only easy to install, but also when placed near the test piece, the radiated electromagnetic wave presents the phase characteristics of a plane wave near the antenna aperture, and the test piece can always be located in the main beam of the antenna, thereby improving the electromagnetic field strength amplitude and field strength uniformity in the test area of ​​the test piece, reducing the requirements for the test transmission power, reducing the cost of the test device and the test operation cost, and ensuring the adequacy and repeatability of the test, thereby improving the test accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Schematic diagram of a near-field shaped antenna for electromagnetic compatibility testing according to the present invention;

[0020] Figure 2 Schematic diagram of the ground plate frame of the near-field shaping antenna used for electromagnetic compatibility testing of the present invention

[0021] In the figure, there are ground plate frame 1, ground plate 10, guide wheel 11, pole plate 2, vertical projection 20, input end edge 202, radiation edge 21, proximal vertical edge 22, proximal concave edge 220, proximal oblique edge 221, distal vertical edge 23, notch 24, first upper edge 241, second upper edge 242, first arcuate edge 243, second arcuate edge 244, straight edge 245, additional oscillator 25, connector 3, antenna input end 201, inner conductor 31 and outer conductor 32. DETAILED DESCRIPTION

[0022] The specific embodiments of the present invention will be further described below in conjunction with the accompanying drawings and examples. The specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0023] The implementation scheme adopted by the present invention is: the near-field shaping antenna for electromagnetic compatibility testing includes a ground plate frame 1, a pole plate 2 and a connector 3; the ground plate frame 1 includes a ground plate 10 and a plurality of guide wheels 11; the ground plate 10 and the pole plate 2 are made of materials with good conductive properties; the pole plate 2 is perpendicular to the ground plate 10, and the pole plate 2 and the ground plate 10 constitute the two poles of the antenna; at the antenna input end 201, the inner conductor 31 of the connector 3 is connected to the pole plate 2, and the outer conductor 32 of the connector 3 is connected to the ground plate 10; the length of the vertical projection 20 of the pole plate 2 on the plane where the ground plate 10 is located is less than one-third of the maximum operating wavelength; the pole plate 2 includes an input end edge 202, a radiation edge 21, a proximal vertical edge 22, a proximal concave edge 220, and a proximal oblique edge 221, distal vertical edge 23, first upper edge 241, second upper edge 242 and notch 24; near the antenna input end 201, the plate 2 has an input end edge 202, which is a straight line and parallel to the ground plate 10; one end of the input end edge 202 is connected to the proximal vertical edge 22 near the connector 3, and the other end of the input end edge 202 is connected to the radiation edge 21; the radiation edge 21 is in the shape of a curve; the end of the radiation edge 21 closest to the ground plate 10 is connected to the input end edge 202, and the other end of the radiation edge 21 is connected to the distal vertical edge 23; the distance from the radiation edge 21 to the ground plate 10 is gradual, and at the point where the radiation edge 21 is connected to the input end edge 202, the radiation edge 21 The distance to the ground plane 10 is the shortest, and the distance from the radiating edge 21 to the ground plane 10 is the largest at the point where the radiating edge 21 is connected to the distal vertical edge 23; the distance from the radiating edge 21 to the ground plane 10 becomes larger and larger from the point where the radiating edge 21 is connected to the input end edge 202 to the point where the radiating edge 21 is connected to the distal vertical edge 23; the proximal vertical edge 22 is perpendicular to the ground plane 10, one end of the proximal vertical edge 22 is connected to the input end edge 202, and the other end is connected to the proximal oblique edge 221, with a proximal concave edge 220 between the two ends; the distal vertical edge 23 is a straight line, which is perpendicular to the ground plane 10, the proximal end of the distal vertical edge 23 is connected to the radiating edge 21, and the distal end of the distal vertical edge 23 is connected to the proximal oblique edge 221. End 230 is connected to the second upper edge 242; the proximal oblique edge 221 is in the shape of a straight line; one end of the proximal oblique edge 221 is connected to the proximal vertical edge 22, and the other end is connected to the first upper edge 241; the connection point between the proximal oblique edge 221 and the first upper edge 241 is in the vertical projection of the plane where the grounding plate 10 is located, and is located between the vertical projection of the proximal vertical edge 22 on the plane where the grounding plate 10 is located and the vertical projection of the distal vertical edge 23 on the plane where the grounding plate 10 is located; there is a recess 24 between the first upper edge 241 and the second upper edge 242, and the recess 24 extends into the interior of the electrode 2, so that an additional vibrator 25 is formed on the upper part of the electrode 2; the surface of the grounding plate 10 is a plane, and when working, the grounding plate 10 is in electrical contact with the ground.

[0024] At the notch 24, the edge of the electrode 2 includes a first curved edge 243, a second curved edge 244 and a straight edge 245; one end of the first curved edge 243 is connected to the first upper edge 241, and the other end is connected to the second curved edge 244, and the internal angle between the first curved edge 243 and the first upper edge 241 is less than 45 degrees; one end of the second curved edge 244 is connected to the first curved edge 243, and the other end is connected to the straight edge 245, and the internal angle between the second curved edge 244 and the first curved edge 243 is an acute angle; one end of the straight edge 245 is connected to the second curved edge 244, and the other end is connected to the second upper edge 242, the internal angle between the straight edge 245 and the second curved edge 244 is an acute angle, and the internal angle between the straight edge 245 and the second upper edge 242 is an obtuse angle; the size of the proximal concave edge 220 is changed so that the radiation field of the antenna is maximized in the test area of ​​the test piece.

[0025] The additional vibrator 25 is composed of a proximal oblique edge 221, a first upper edge 241 and a first curved edge 243; according to the requirement of maximizing the vertical polarization radiation field, the angle between the proximal oblique edge 221 and the grounding plate 10, the shape and size of the first curved edge 243, and the distance and length from the first upper edge 241 to the grounding plate 10 are determined.

[0026] The guide wheel 11 is flippable. When working, the guide wheel 11 flips over to the ground plate 10 so that the ground plate maintains electrical contact with the ground of the test chamber; when moving, the guide wheel 11 flips under the ground plate 10 to facilitate the movement of the entire antenna.

[0027] At the antenna input end 201 , the distance from the input end edge 202 to the ground plane 10 makes the characteristic impedance at this location 50 ohms.

[0028] The shape of the radiation edge 21 can be determined according to the matching requirements within the operating frequency band.

[0029] The guide wheel 11 makes the antenna easy to move, allowing it to be moved to the optimal test position, greatly facilitating testing. During operation, the guide wheel 11 flips over the ground plate 10, ensuring electrical contact between the ground plate 10 and the test chamber. This fully utilizes the entire chamber floor as another antenna plate, allowing a smaller grounding area to achieve a greater grounding effect. While maintaining antenna radiation performance, the antenna's height is reduced, allowing the antenna to be very close to the test object, minimizing distance attenuation and reducing the test transmission power requirement. Furthermore, when the antenna is very close to the test object on the ground, the test object is always within the antenna's main lobe.

[0030] When the antenna operates in the low-frequency band, the test area is in the near zone of the antenna, and two main radiating units are in effect. One is the main radiating unit, which is composed of the radiating edge 21, the distal vertical edge 22, the second upper edge 242, the straight edge 245, the second curved edge 244, and a portion of the first curved edge 243; the other radiating unit is the additional oscillator 25. The field strength in the test area is the superposition of the field strengths of these two radiating units in the near zone. Since the near-zone field is not only a radiation field but also an induction field, the design of its superposition is far more complex than that of the far-zone field. Detailed design requires the use of simulation tools to shape the electromagnetic field in the test area. By changing the size of the proximal concave edge 220 and its position on the proximal vertical edge 22, the relative amplitude and phase of the currents in the two radiating units can be adjusted to make the power density in the test area as high as possible. Changing the length of proximal beveled edge 221, its angle with ground plane 10, and the shape of first arcuate edge 243 not only adjusts the radiation intensity of supplementary dipole 25 but also maximizes the vertically polarized radiation field within the test area. When the antenna operates in the high-frequency band, the test area is in the far range of the antenna, and the primary radiating element plays a primary role.

[0031] The curve shape of radiating edge 21 is an exponential or power function, such as a straight line or square function, and is determined based on matching requirements within the operating frequency band. For example, let y be the distance from radiating edge 21 to ground plane 10, the vertical projection of the connection point between radiating edge 21 and input edge 202 on ground plane 10 be the coordinate origin, and the vertical projection 20 of radiating edge 21 on ground plane 10 be the x-axis, with the x-axis pointing toward distal vertical edge 23. In this case, the exponential curve shape parameters of radiating edge 21 are: The distance between input edge 202 and the ground plane is 20 mm, and the operating frequency band of the low-frequency broadband antenna tested for electromagnetic compatibility is 20 MHz to 220 MHz.

[0032] The use of the ground plate frame 1 reduces the height of the antenna while ensuring the antenna radiation performance, and makes the antenna easy to place flexibly. The antenna can be very close to the test piece, and the distance attenuation is small, which can reduce the requirement for the test transmission power because even if the antenna is very close to the test piece on the ground, the test piece can always be in the main lobe of the antenna.

[0033] Although the first upper edge 241 and the second upper edge 242 are far away from the radiation edge 21, their specific shapes have little impact on the matching and radiation performance of the antenna in the high frequency band, but have a relatively large impact on the performance in the low frequency band, especially the performance of the vertically polarized radiation field.

[0034] The distance between the point where the proximal vertical edge 22 connects with the input end edge 202 and the point where the proximal vertical edge 22 connects with the proximal oblique edge 221 is slightly less than one-eighth of the maximum operating wavelength; the shape of the proximal vertical edge 22 near the point where it connects with the proximal oblique edge 221 can be slightly changed relative to the straight line to improve the performance in the low frequency band, especially the performance of the vertically polarized radiation field.

[0035] The shape of the distal vertical edge 23 may be slightly changed, and the shape near the position where it is connected to the second upper edge 242 may be slightly changed relative to the straight line, as long as the area and shape of the electrode plate 2 are not significantly changed; it may also be an exponential curve.

[0036] The length of the distal vertical edge 23 is slightly less than one seventh of the maximum operating wavelength. Under the condition that the position where the distal vertical edge 23 is connected to the second upper edge 242 remains unchanged, the length of the distal vertical edge 23 can be reduced, that is, the distance from the radiating edge 21 to the ground plate frame 1 can be increased.

[0037] The thickness of the ground plate 10 should ensure that the ground plate frame 1 has sufficient strength for use; the thickness of the electrode plate 2 needs to ensure that the electrode plate 2 has sufficient supporting strength.

[0038] The plate 2 is fixed by a support frame made of non-metallic material to avoid affecting the performance of the antenna. The support frame can be placed on the ground plate frame 1.

[0039] According to the above description, the present invention can be realized.

[0040] The above descriptions are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. within the design methods and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. Near-field shaped antenna for electromagnetic compatibility testing, characterized by The antenna comprises a ground plate frame (1), a plate (2) and a connector (3); the ground plate frame (1) comprises a ground plate (10) and a plurality of guide wheels (11); the ground plate (10) and the plate (2) are made of a material with good electrical conductivity; the plate (2) is perpendicular to the ground plate (10), and the plate (2) and the ground plate (10) form two poles of the antenna; at the antenna input end (201), the inner conductor (31) of the connector (3) is connected to the plate (2), and the outer conductor (32) of the connector (3) is connected to the ground plate (10); the length of the vertical projection (20) of the plate (2) on the plane where the ground plate (10) is located is less than one-third of the maximum working wavelength; the plate (2) comprises an input end edge (202 ), a radiating edge (21), a proximal vertical edge (22), a proximal concave edge (220), a proximal oblique edge (221), a distal vertical edge (23), a first upper edge (241), a second upper edge (242) and a notch (24); near the antenna input end (201), the plate (2) has an input end edge (202), which is in the shape of a straight line and is parallel to the ground plate (10); one end of the input end edge (202) is connected to the proximal vertical edge (22) near the joint (3), and the other end of the input end edge (202) is connected to the radiating edge (21); the radiating edge (21) is in the shape of a curve; the radiating edge (21) is closest to the ground plate (10). One end is connected to the input end edge (202), and the other end of the radiation edge (21) is connected to the distal vertical edge (23); the distance between the radiation edge (21) and the ground plate (10) is gradually changed, and the distance between the radiation edge (21) and the ground plate (10) is the shortest at the point where the radiation edge (21) is connected to the input end edge (202), and the distance between the radiation edge (21) and the ground plate (10) is the largest at the point where the radiation edge (21) is connected to the distal vertical edge (23); the distance between the radiation edge (21) and the ground plate (10) increases from the point where the radiation edge (21) is connected to the input end edge (202) to the point where the radiation edge (21) is connected to the distal vertical edge (23); The proximal vertical edge (22) is perpendicular to the ground plate (10), one end of the proximal vertical edge (22) is connected to the input end edge (202), and the other end is connected to the proximal oblique edge (221), with a proximal concave edge (220) between the two ends; the distal vertical edge (23) is in the shape of a straight line, and is perpendicular to the ground plate (10), the proximal end of the distal vertical edge (23) is connected to the radiation edge (21), and the distal end (230) of the distal vertical edge (23) is connected to the second upper edge (242); the proximal oblique edge (221) is in the shape of a straight line; one end of the proximal oblique edge (221) is connected to the proximal vertical edge (22), and the other end is connected to the first upper edge (241);The vertical projection of the connection point between the proximal oblique edge (221) and the first upper edge (241) on the plane where the grounding plate (10) is located is located between the vertical projection of the proximal vertical edge (22) on the plane where the grounding plate (10) is located and the vertical projection of the distal vertical edge (23) on the plane where the grounding plate (10) is located; there is a notch (24) between the first upper edge (241) and the second upper edge (242), and the notch (24) extends into the interior of the electrode (2), so that an additional vibrator (25) is formed on the upper part of the electrode (2); the surface of the grounding plate (10) is a plane, and when in operation, the grounding plate (10) is in electrical contact with the ground; The additional vibrator (25) is composed of a proximal oblique edge (221), a first upper edge (241), and a first arc-shaped edge (243); based on the requirement of maximizing the vertical polarization radiation field, the angle between the proximal oblique edge (221) and the grounding plate (10), the shape and size of the first arc-shaped edge (243), and the distance and length from the first upper edge (241) to the grounding plate (10) are determined.

2. The near-field shaped antenna for electromagnetic compatibility testing according to claim 1, characterized in that At the notch (24), the edge of the electrode plate (2) includes a first arcuate edge (243), a second arcuate edge (244), and a straight edge (245); one end of the first arcuate edge (243) is connected to the first upper edge (241), and the other end is connected to the second arcuate edge (244), and the inner angle between the first arcuate edge (243) and the first upper edge (241) is less than 45 degrees; one end of the second arcuate edge (244) is connected to the first arcuate edge (243), and the other end is connected to the straight edge (245). The second arcuate side (244) and the first arcuate side (243) are connected, and the inner angle between the second arcuate side (244) and the first arcuate side (243) is an acute angle; one end of the straight side (245) is connected to the second arcuate side (244), and the other end is connected to the second upper edge (242), the inner angle between the straight side (245) and the second arcuate side (244) is an acute angle, and the inner angle between the straight side (245) and the second upper edge (242) is an obtuse angle; the size of the proximal concave edge (220) is changed so that the radiation field of the antenna is maximized in the test area of ​​the test piece.

3. The near-field shaped antenna for electromagnetic compatibility testing according to claim 1, characterized in that The guide wheel (11) is flippable. When working, the guide wheel (11) flips over to the top of the ground plate (10), so that the ground plate maintains electrical contact with the ground of the test chamber; when moving, the guide wheel (11) flips under the ground plate (10), facilitating the movement of the entire antenna.

4. The near-field shaped antenna for electromagnetic compatibility testing according to claim 1, characterized in that At the antenna input end (201), the distance from the input end edge (202) to the ground plane (10) makes the characteristic impedance at this location 50 ohms.

5. The near-field shaped antenna for electromagnetic compatibility testing according to claim 1, characterized in that The shape of the radiation edge (21) is determined according to the matching requirements within the operating frequency band.

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