Ultra-wideband tapered slot line composite antenna for electromagnetic compatibility testing

Abstract

The application discloses a kind of ultra-wideband gradual slot line composite antennas for electromagnetic compatibility test, including slot line radiator, coaxial connector and open loop radiator, and be located at the edge impedance network and center impedance network of open loop radiator;Change the circumference of open loop radiator and the width of guide band, the loading position and impedance value of edge impedance network and center impedance network and the length size of reverse radiation arm, back radiation arm, can adjust the impedance bandwidth and front-back ratio of the antenna.The ultra-wideband antenna effectively reduces the electrical size of antenna and realizes the ultra-wide working frequency band, maintains excellent unidirectional end-fire radiation characteristics and extremely high cross-polarization purity in the entire ultra-wideband working frequency band, and provides a high-performance and stable solution for electromagnetic compatibility test of ultra-wideband system.

Description

Technical Field

[0001] This invention relates to the field of antenna technology, and in particular to an ultra-wideband tapered slot line composite antenna for electromagnetic compatibility testing. Background Technology

[0002] With the increasing demand for electromagnetic compatibility (EMC) testing in modern electronic systems, EMC testing has become a crucial method in system development and verification. In traditional testing environments for ultra-wideband devices, multiple transmitting antennas are typically required to achieve effective full-band coverage. Log-periodic antennas are commonly used in low-frequency testing, but their physical size is relatively large, and existing commercially available log-periodic antennas exhibit relatively high standing waves (VSWRs) in the low-frequency range. Therefore, developing a miniaturized antenna capable of covering a wide bandwidth has become an urgent need.

[0003] Among various ultra-wideband antennas, tapered slotted wire antennas have become an important research direction for achieving this goal due to their advantages such as simple structure, wide impedance bandwidth, and stable directivity. To extend the low-frequency operating band of tapered slotted wire antennas, existing technologies often involve slotting the antenna or introducing parasitic structures. However, this extension method often comes at the cost of radiation performance. In the low-frequency band, tapered slotted wire antennas struggle to maintain stable end-fire characteristics, and the radiation mode degenerates into quasi-omnidirectional radiation, leading to enhanced backscattering and a significant deterioration in the front-to-back ratio. In electromagnetic compatibility testing environments, excessive backscattering can cause multipath reflections and signal interference from the surrounding environment, severely affecting measurement accuracy. Furthermore, existing technologies often employ the method of loading resistors onto tapered slotted wire antennas, but this commonly used resistor loading method leads to a decrease in radiation efficiency across the entire operating frequency band, including the mid-to-high frequency band. Summary of the Invention

[0004] Technical Problems: The purpose of this invention is to propose an ultra-wideband tapered slot line composite antenna for electromagnetic compatibility testing, in order to solve the following technical problems: (1) the degradation of end-fire characteristics and strong back radiation in the low-frequency band of miniaturized tapered slot line antennas, which causes multipath reflection and signal interference in the electromagnetic compatibility testing environment. This invention can maintain stable end-fire characteristics in the low-frequency band with a small electrical size and suppress back radiation, thus significantly improving the front-to-back ratio of the low-frequency antenna; (2) the problem that the conventional resistor loading method in the design of traditional resistor-loaded tapered slot line antennas will cause a serious decrease in the radiation efficiency of the antenna across the entire frequency band, including the mid-to-high frequency band. This invention can achieve ultra-wideband coverage while avoiding the absorption of radiated energy in the mid-to-high frequency band, thus ensuring high radiation efficiency of the antenna in the mid-to-high frequency band.

[0005] Technical Solution: The present invention provides an ultra-wideband tapered slotted wire composite antenna for electromagnetic compatibility testing, comprising an open loop radiator, a slotted wire radiator located within the opening of the open loop radiator, and a coaxial connector connected to the slotted wire radiator; the slotted wire radiator is a metallic conductor, comprising a slotted wire radiating arm, a reverse radiating arm, and a rear radiating arm symmetrically connected vertically; the open loop radiator comprises a first conductor strip, a first edge impedance network, a second conductor strip, a center impedance network, a third conductor strip, a second edge impedance network, and a fourth conductor strip connected in sequence; the first edge impedance network and the second edge impedance network are symmetrically arranged on the upper and lower sides of the open loop radiator, and the center impedance network is located in the middle of the inner side of the open loop radiator; the opening of the open loop radiator is located at the end of the slotted wire radiator.

[0006] in, The grooved radial arm includes an upper radial arm and a lower radial arm arranged symmetrically at the top and bottom, and the gap between the upper and lower radial arms forms the groove.

[0007] The front part of the groove is a uniform groove, the front end of which extends towards the front of the groove radiator and bends downward, and the end unfolds to form a circular hole; the rear part of the groove is a gradient groove, the rear end of the uniform groove is connected to the front end of the gradient groove, and the width of the gap of the gradient groove gradually increases from the front to the rear of the groove, with the widest point being the end of the groove radiator. The upper radiating arm is connected to the first reverse radiating arm and the first rear radiating arm on the same side to form a slot with an opening; the lower radiating arm is connected to the second reverse radiating arm and the second rear radiating arm on the same side to form a slot with an opening.

[0008] The first edge impedance network and the second edge impedance network have the same structure, each including an edge dielectric substrate, an edge conductor etched on the surface of the edge dielectric substrate, and an edge impedance element located in the middle of the edge conductor; the second conductor strip and the third conductor strip are provided with one or more weight reduction holes.

[0009] The edge conductor has a gap in the middle, and the edge impedance element crosses the gap. The two ends of the edge impedance element are connected to the edge conductors on both sides of the gap to form a continuous conductive path. The impedance value of the edge impedance element matches the average characteristic impedance of the open ring radiator, and the impedance value of the edge impedance element is adjusted according to the voltage standing wave ratio and front-to-back ratio of the antenna.

[0010] The central impedance network includes a central dielectric substrate, a central conductor etched on the surface of the central dielectric substrate, and a central impedance element located in the middle of the central conductor; a feed hole is provided in the middle of the central dielectric substrate for the feed cable to pass through.

[0011] The center conductor has a gap in the middle, and the center impedance element crosses the gap. The two ends of the center impedance element are connected to the center conductors on both sides of the gap to form a continuous conductive path. The impedance value of the center impedance element is higher than the average characteristic impedance of the open ring radiator, and the impedance value of the center impedance element is adjusted according to the front-to-back ratio and radiation efficiency of the antenna.

[0012] A power feeding inner hole is provided between the uniform groove line and the circular hole of the groove line radiator. The inner conductor of the coaxial connector passes through the power feeding inner hole and crosses the uniform groove line. It is connected to the lower radiating arm at the edge of the gap of the uniform groove line. The outer conductor of the coaxial connector is connected to the left side wall of the groove line radiator.

[0013] The diameter of the power supply inner hole is larger than the inner conductor diameter of the coaxial connector. By adjusting the radial dimension ratio of the two, impedance matching between the port and the coaxial connector can be achieved.

[0014] By combining slotted line radiators and open ring radiators, a frequency-specific radiation mechanism that varies with frequency is realized. In the low-frequency band, the open ring radiator acts as the main radiating element and operates in the loaded loop mode. In the mid-frequency band, the equivalent electric dipole formed by the tapered slot line, together with the magnetic dipole formed by the reverse radiating arm and the rear radiating arm, works in the combined dipole mode. In the high-frequency band, electromagnetic energy is radiated along the edge of the tapered slot line towards the end and operates in the traveling wave mode.

[0015] When the antenna operates in the low-frequency band, the resistance of the edge impedance network and the center impedance network absorbs the terminal reflected current generated by the open-loop radiator to suppress back radiation and improve the front-to-back ratio. The edge impedance element and the center impedance element employ a stepped impedance loading configuration to enhance the front-to-back ratio of the antenna at the low-frequency cutoff frequency. The impedance value is adjusted according to the average characteristic impedance of the open-loop radiator. Furthermore, the resonant characteristics and input impedance are controlled by adjusting the perimeter and conduction band width of the open-loop radiator; a smaller perimeter-to-conduction band width ratio results in a smoother input impedance response.

[0016] When the antenna operates in the mid-frequency band, the amplitude ratio and phase difference between the equivalent magnetic dipole and the equivalent electric dipole are changed by adjusting the length of the reverse radiating arm and the rear radiating arm. The far-field interference effect of the two is used to form Huygens source radiation, thereby optimizing the radiation quality and front-to-back ratio in the end-fire direction without increasing the physical size of the antenna.

[0017] When the antenna operates in the high-frequency band, the active radiating region shifts towards the initial narrow slot region of the slot radiator as the frequency increases. This decouples the high-frequency radiation process from the outer open ring radiator, the reverse radiating arm, and the rear radiating arm in the electromagnetic space, avoiding interference from the coupling of the outer structure to the high-frequency radiation pattern and ensuring the stability of the radiation pattern throughout the entire operating frequency band.

[0018] Beneficial effects: The ultra-wideband tapered slot line composite antenna for electromagnetic compatibility testing of the present invention has the following advantages: (1) It achieves ultra-wideband single-antenna coverage, and only a single antenna is needed to complete the full-band test. This not only solves the problem of needing to frequently replace multiple antennas in traditional ultra-wideband testing, but also overcomes the defect of large physical size of commonly used log-periodic antennas in low-frequency bands, which greatly simplifies test deployment and improves test efficiency.

[0019] (2) It maintains good low-frequency end-fire characteristics and suppresses back radiation. While maintaining a small electrical size, the present invention can still maintain stable end-fire characteristics and a high front-to-back ratio in the low-frequency band, which solves the problem of deterioration of radiation characteristics in the low-frequency band of traditional miniaturized ultra-wideband tapered slot antennas, eliminates multipath reflection and signal interference caused by back radiation in the electromagnetic compatibility test environment, and ensures measurement accuracy.

[0020] (3) High radiation efficiency in the mid-to-high frequency band is guaranteed. The unique loading method adopted in this invention can effectively extend the low-frequency bandwidth while avoiding ineffective absorption and dissipation of radiated energy in the mid-to-high frequency band. This solves the defect that conventional loading methods will cause the antenna to lose radiation efficiency across the entire frequency band, including the mid-to-high frequency band, and ensures that the antenna maintains high radiation efficiency in the mid-to-high frequency band.

[0021] (4) It has extremely high polarization purity, effectively preventing polarization contamination. The composite antenna has an extremely high cross-polarization ratio, which can maintain excellent polarization purity throughout the entire ultra-wideband operating frequency range, effectively preventing polarization contamination during the testing process. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the ultra-wideband tapered groove composite antenna structure of the present invention.

[0023] Figure 2 This is a schematic diagram of the slot radiator of the ultra-wideband tapered slot composite antenna of the present invention.

[0024] Figure 3 This is a schematic diagram of the edge impedance network of the ultra-wideband tapered slot composite antenna of the present invention.

[0025] Figure 4 This is a schematic diagram of the center impedance network of the ultra-wideband tapered slot composite antenna of the present invention.

[0026] Figure 5 This is a schematic diagram of the reflection coefficient curve of the ultra-wideband tapered slot composite antenna of the present invention.

[0027] Figure 6 This is a schematic diagram of the gain curve of the ultra-wideband tapered slot composite antenna of the present invention.

[0028] Figure 7 This is a schematic diagram of the cross-polarization ratio and front-to-back ratio curves of the ultra-wideband tapered slot composite antenna of the present invention.

[0029] The diagram includes: slotted radiator 1, coaxial connector 2, open annular radiator 3, slotted radiator arm 10, upper radiator arm 100, first reverse radiator arm 110, first rear radiator arm 120, lower radiator arm 101, second reverse radiator arm 111, second rear radiator arm 121, circular hole 102, feed inner hole 103, slotted line 13, uniform slotted line 130, gradient slotted line 131, end 14, first conductor strip 301, second conductor strip 302, third conductor strip 303, fourth conductor strip 304, weight reduction hole 300, first edge impedance network 31a, second edge impedance network 31b, center impedance network 32, edge dielectric substrate 310, edge conductor 311, edge impedance element 312, center dielectric substrate 320, center conductor 321, center impedance element 322, feed hole 323, structural fastener 4, and substrate fastener 5. Detailed Implementation

[0030] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0031] This invention discloses an ultra-wideband tapered slot line composite antenna for electromagnetic compatibility testing, comprising a slot line radiator 1, a coaxial connector 2, and an open loop radiator 3. The slot line radiator 1 is a metallic conductor and includes a slot line radiating arm 10, a reverse radiating arm, and a rear radiating arm. The slot line radiating arm 10 includes an upper radiating arm 100 and a lower radiating arm 101 symmetrically arranged vertically, with the gap between the upper and lower radiating arms 101 forming a slot line 13. The middle section of the slot line 13 is a uniform slot line 130, one end of which extends towards the rear of the slot line radiator 1 and bends downward, with the gap at its end unfolding to form a circular hole 102. The other end of the uniform slot line 130 connects with the tapered slot line. One end of 131 is connected, and along the other end of the gradient groove line 131, the width of the gap in the gradient groove line 131 gradually increases, with the maximum width at the end 14 of the groove line radiator 1; there are two reverse radiation arms, namely the first reverse radiation arm 110 and the second reverse radiation arm 111, symmetrically distributed on both sides of the gradient groove line 131; there are two rear radiation arms, namely the first rear radiation arm 120 and the second rear radiation arm 121, symmetrically distributed on both sides of the gradient groove line 131; the upper radiation arm 100 and the first reverse radiation arm and the first rear radiation arm on the same side form a slot with an opening, and the lower radiation arm 101 and the second reverse radiation arm and the second rear radiation arm on the same side form a slot with an opening; The open-circuit radiator 3 includes four conductor strips: a first conductor strip 301, a second conductor strip 302, a third conductor strip 303, and a fourth conductor strip 304; two edge impedance networks: a first edge impedance network 31a and a second edge impedance network 31b; and a center impedance network 32. The two edge impedance networks and the center impedance network 32 are located between the two conductor strips, ensuring that all conductor strips maintain direct electrical connection. One or more weight-reducing holes 300 are present on the conductor strips. The two edge impedance networks are symmetrically arranged on both sides of the open-circuit radiator 3. Each edge impedance network includes an edge dielectric substrate 310, edge wires 311 etched on the surface of the edge dielectric substrate 310, and edge impedance elements 312. The central impedance network 32 includes a central dielectric substrate 320, a central conductor 321 etched on the surface of the central dielectric substrate 320, and a central impedance element 322. The central dielectric substrate 320 has a feed hole 323 for the feed cable to pass through. The central impedance network 32 is located in the middle of the rear side of the open annular radiator 3. The edge impedance network and the central impedance network are both fixed to the edge of the open annular radiator 3 by substrate fasteners 5. The open annular radiator 3 forms an open annular shape near the outer edge of the slotted radiator 1, and its opening is located at the end 14 of the radiator. The two ends of the open annular radiator 3 are connected to the slotted radiator 1 by structural fasteners 4, and the connection point is located between the slotted radiating arm 10 and the reverse radiating arm 11. A power supply inner hole 103 is provided between the uniform groove 130 of the groove radiator 1 and the circular hole 102. The inner conductor of the coaxial connector 2 passes through the power supply inner hole 103, crosses the uniform groove 130, and connects with the lower radiating arm 101 at the edge of the gap of the uniform groove 130. The outer conductor of the coaxial connector 2 is connected to the left side wall of the groove radiator 1.

[0032] The diameter of the power supply inner hole 103 is larger than the inner conductor diameter of the coaxial connector 2. By adjusting the radial dimension ratio of the two, impedance matching between the port and the coaxial connector 2 can be achieved.

[0033] On the edge impedance network 31, there is a gap in the middle of the edge conductor 311, and the edge impedance element 312 spans the gap. The two ends of the edge impedance element 312 are respectively connected to the edge conductor 311 located on both sides of the gap to form a continuous conductive path. The impedance value of the edge impedance element 312 matches the average characteristic impedance of the open ring radiator 3, and the impedance value of the edge impedance element 312 is adjusted according to the voltage standing wave ratio and front-to-back ratio of the antenna.

[0034] On the central impedance network 32, there is a gap in the middle of the central conductor 321. The central impedance element 322 spans the gap, and the two ends of the central impedance element 322 are respectively connected to the central conductor 321 located on both sides of the gap to form a continuous conductive path. The impedance value of the central impedance element 322 is higher than the average characteristic impedance of the open ring radiator 3, and the impedance value of the central impedance element 322 is adjusted according to the front-to-back ratio and radiation efficiency of the antenna.

[0035] By combining the slotted radiator 1 and the open-loop radiator 3, a frequency-specific radiation mechanism that varies with frequency is realized. In the low-frequency band, the open-loop radiator 3 acts as the main radiation element and operates in the loaded loop mode. In the mid-frequency band, the equivalent electric dipole formed by the tapered slotted line 131, together with the magnetic dipole formed by the reverse radiation arm and the rear radiation arm, works in the combined dipole mode. In the high-frequency band, electromagnetic energy is radiated along the edge of the tapered slotted line 131 towards the end and operates in the traveling wave mode.

[0036] When the antenna operates in the low-frequency band, the resistance in the edge impedance network and the center impedance network absorbs the end reflection current generated by the open loop radiator 3 to suppress back radiation and improve the front-to-back ratio. The edge impedance element 312 and the center impedance element 322 adopt a stepped impedance loading configuration to enhance the front-to-back ratio of the antenna at the low-frequency cutoff frequency. The impedance value is adjusted according to the average characteristic impedance of the open loop radiator 3, and its resonance characteristics and input impedance are controlled by adjusting the perimeter and conduction band width of the open loop radiator 3. The smaller the ratio of perimeter to conduction band width, the smoother the input impedance response.

[0037] When the antenna operates in the mid-frequency band, the amplitude ratio and phase difference between the equivalent magnetic dipole and the equivalent electric dipole are changed by adjusting the length of the reverse radiating arm and the rear radiating arm. The far-field interference effect of the two is used to form Huygens source radiation, thereby optimizing the radiation quality and front-to-back ratio in the end-fire direction without increasing the physical size of the antenna.

[0038] When the antenna operates in the high-frequency band, the active radiation region shifts towards the initial narrow slot region of the slot radiator 1 as the frequency increases. This decouples the high-frequency radiation process from the outer open ring radiator 3, the reverse radiation arm, and the rear radiation arm in the electromagnetic space, thus avoiding interference from the coupling of the outer structure to the high-frequency radiation pattern and ensuring the stability of the radiation pattern throughout the entire operating frequency band.

[0039] This embodiment provides an ultra-wideband tapered slot line composite antenna with overall dimensions of 255mm × 200mm × 80mm. The electrical dimensions corresponding to the lowest operating frequency of 0.27GHz are approximately... The antenna's main structure is made of AL6061 aluminum alloy to ensure overall structural robustness. The inner edge profile of the gradient groove is defined by a first exponential gradient curve, while the outer edge profile is defined by a second exponential gradient curve. The formulas for the two curves are defined as follows: and : , , in =0.288, =0.830, =2.67, =0.517, =0.03, =0.02.

[0040] An open-loop radiator 3 is connected to the end of the slotted radiator 1, with an outer dimension of 219mm × 219mm × 80mm. An edge impedance network and a center impedance network 32 are loaded on the open-loop radiator 3. The edge dielectric substrate 310 and the center dielectric substrate 320 are made of FR-4 board material. The edge impedance element 312 and the center impedance element 322 are respectively soldered to the conductor strips of the edge dielectric substrate 310 and the center dielectric substrate 320 to achieve direct electrical connection of all conductor strips.

[0041] In the initial low-frequency loaded loop mode phase, since the aperture of the slotted wire radiator 1 is insufficient to generate effective end-fire radiation in the low-frequency band, the open-ring radiator 3 serves as the primary radiating element. By adjusting the perimeter and conduction band width of the open-ring radiator 3, its input impedance response can be effectively adjusted. A decrease in the ratio of perimeter to conduction band width effectively suppresses sharp resonance peaks in the input impedance response, thereby achieving a flat impedance characteristic in the 0.27 GHz to 0.45 GHz frequency band. Considering the overall quality of the open-ring radiator 3, the final ratio of perimeter to conduction band width is determined to be 4.64. Within this frequency band, the open-ring radiator 3 supports standing wave current distribution and generates a bidirectional radiation pattern. To maintain unidirectional end-fire directivity, an impedance network is introduced at the current antinode of the open-ring radiator 3 to absorb end reflections and suppress back radiation. In this embodiment, both the edge impedance network and the center impedance network 32 are implemented using a single resistor. The average characteristic impedance of the open-loop radiator 3 is 200 ohms. If only a resistor is loaded at the center of the open-loop radiator 3, its absorption of reflected energy is extremely limited, resulting in a front-to-back ratio of only 2 dB. Therefore, this embodiment adopts a stepped impedance loading scheme, that is, a center impedance element 322 is loaded at the center of the open-loop radiator 3, and edge impedance elements 312 are symmetrically loaded on its upper and lower sides. The resistance value of the edge impedance element 312 is mainly used to improve input impedance matching and suppress part of the back radiation, and its resistance value needs to match the average characteristic impedance of the open-loop radiator 3. In the actual design, based on the antenna's voltage standing wave ratio and front-to-back ratio, the resistance value of the edge impedance element 312 is finally optimized and determined to be 180 ohms. The center impedance element 322 is mainly used to absorb the reflected wave energy along the center path, and its resistance value is higher than the average characteristic impedance of the open-loop radiator 3. If the resistance value is too high, the antenna efficiency will drop sharply; if it is too low, it will not be able to effectively absorb the reflected wave energy, resulting in a deterioration of the front-to-back ratio. Therefore, while ensuring a certain level of radiation efficiency, adjustments were made based on the antenna's front-to-back ratio and radiation efficiency, ultimately optimizing the resistance of the center impedance element 322 to 470 ohms. This distributed configuration can significantly attenuate backward radiation and increase the front-to-back ratio at the lowest cutoff frequency to over 11 dB, while maintaining the antenna's overall radiation efficiency between 29% and 58% within this frequency band.

[0042] When the mid-frequency combined dipole mode is in the 0.45GHz to 0.69GHz frequency band, the antenna structure is converted into a combination mode of mutually orthogonal electric and magnetic dipoles to generate unidirectional radiation. The equivalent electric dipole is formed by the longitudinal current flowing along the slot radiator 1, while the transverse magnetic current flowing around the open slot formed by the reverse and rear radiating arms induces an equivalent magnetic dipole. This embodiment utilizes the far-field interference effect between these two orthogonal radiators to make the antenna equivalent to a Huygens source, and adjusts the amplitude ratio and phase difference between the magnetic and electric dipoles by optimizing the geometric parameters of the reverse and rear radiating arms. By adjusting the length parameters of the reverse and rear radiating arms, the amplitude ratio and phase difference between the magnetic and electric dipoles can be matched, thus achieving optimal front-to-back ratio performance in both full-wave simulation and theoretical analysis.

[0043] In the high-frequency traveling-wave mode band of 0.69 GHz to 12 GHz, the antenna's radiation mechanism naturally transitions to the traditional end-fire traveling-wave mode of a tapered slot radiator. At this point, electromagnetic energy is tightly confined to the exponentially tapered edge inside slot radiator 1 and efficiently radiated into free space along the opening direction. Due to the shorter wavelength in the high-frequency band, the radiation region shifts towards the narrow slot region of slot radiator 1, ensuring that most of the energy is radiated before reaching the reverse radiating arm, the rear radiating arm, and the open-loop radiator 3. This spatial decoupling characteristic prevents unnecessary coupling interference or distortion of the high-frequency pattern by external low-frequency and mid-frequency structural components, ensuring that the antenna maintains stable end-fire radiation characteristics, excellent polarization purity, and effective back-radiation suppression capabilities throughout the entire ultra-wideband range of 0.27 GHz to 12 GHz.

[0044] Test results show that the antenna in this embodiment achieves stable unidirectional end-fire radiation in the ultra-wideband range of 0.27 GHz to 12 GHz, reaching a frequency ratio of 44.4:1. The antenna achieves a gain range of -0.6 dBi to 11 dBi, with a front-to-back ratio greater than 11 dB at the lowest cutoff frequency, and a cross-polarization ratio greater than 28 dB across the entire frequency band. The antenna radiation efficiency is higher than 58% in the mid-frequency band and higher than 79% in the high-frequency band. This antenna significantly extends the low-frequency operating limit without increasing physical size, meeting the comprehensive requirements of antenna miniaturization, high polarization purity, and stable radiation pattern in the electromagnetic compatibility testing of ultra-wideband systems.

[0045] The technical solution of the present invention is not limited to the specific embodiments described above. For example, the present invention is an ultra-wideband antenna operating in the range of 0.27 GHz to 12 GHz. By changing the size, it can be applied to other bands. All technical modifications made according to the technical solution of the present invention fall within the protection scope of the present invention.

Claims

1. An ultra-wideband tapered slot line composite antenna for electromagnetic compatibility testing, characterized in that... The antenna includes an open-loop radiator (3), a slotted wire radiator (1) located inside the opening of the open-loop radiator (3), and a coaxial connector (2) connected to the slotted wire radiator (1). The slotted wire radiator (1) is a metal conductor and includes a slotted wire radiating arm (10) symmetrically connected vertically, a reverse radiating arm, and a rear radiating arm. The open-loop radiator (3) includes a first conductor strip (301), a first edge impedance network (31a), a second conductor strip (302), a center impedance network (32), a third conductor strip (303), a second edge impedance network (31b), and a fourth conductor strip (304) connected in sequence. The first edge impedance network (31a) and the second edge impedance network (31b) are symmetrically arranged on the upper and lower sides of the open-loop radiator (3), and the center impedance network (32) is located in the middle of the inner side of the open-loop radiator (3). The opening of the open-loop radiator (3) is located at the end (14) of the slotted wire radiator (1). The groove line radial arm (10) includes an upper radial arm (100) and a lower radial arm (101) arranged symmetrically above and below, and the gap between the upper radial arm (100) and the lower radial arm (101) forms a groove line (13). The upper radiating arm (100) is connected to the first reverse radiating arm (110) and the first rear radiating arm (120) on the same side to form a slot with an opening; the lower radiating arm (101) is connected to the second reverse radiating arm (111) and the second rear radiating arm (121) on the same side to form a slot with an opening.

2. The ultra-wideband tapered slot line composite antenna for electromagnetic compatibility testing according to claim 1, characterized in that, The front part of the groove (13) is a uniform groove (130). The front end of the uniform groove (130) extends towards the front of the groove radiator (1) and bends downward, and the end unfolds to form a circular hole (102). The rear part of the groove (13) is a gradient groove (131). The rear end of the uniform groove (130) is connected to the front end of the gradient groove (131). The width of the gap of the gradient groove (131) gradually increases from the front to the rear of the groove (13), and the widest point is the end (14) of the groove radiator (1).

3. The ultra-wideband tapered slot line composite antenna for electromagnetic compatibility testing according to claim 2, characterized in that, The first edge impedance network (31a) and the second edge impedance network (31b) have the same structure, including an edge dielectric substrate (310), an edge conductor (311) etched on the surface of the edge dielectric substrate (310), and an edge impedance element (312) located in the middle of the edge conductor (311); the second conductor strip (302) and the third conductor strip (303) are provided with one or more weight reduction holes (300).

4. The ultra-wideband tapered slot line composite antenna for electromagnetic compatibility testing according to claim 3, characterized in that, The edge conductor (311) has a gap in the middle, and the edge impedance element (312) spans the gap. The two ends of the edge impedance element (312) are connected to the edge conductor (311) on both sides of the gap to form a continuous conductive path. The impedance value of the edge impedance element (312) matches the average characteristic impedance of the open ring radiator (3), and the impedance value of the edge impedance element (312) is adjusted according to the voltage standing wave ratio and front-to-back ratio of the antenna.

5. The ultra-wideband tapered slot line composite antenna for electromagnetic compatibility testing according to claim 4, characterized in that, The central impedance network (32) includes a central dielectric substrate (320), a central conductor (321) etched on the surface of the central dielectric substrate (320), and a central impedance element (322) located in the middle of the central conductor (321); a feed hole (323) is provided in the middle of the central dielectric substrate (320) for the feed cable to pass through.

6. The ultra-wideband tapered slot line composite antenna for electromagnetic compatibility testing according to claim 5, characterized in that, The center conductor (321) has a gap in the middle, and the center impedance element (322) spans the gap. The two ends of the center impedance element (322) are connected to the center conductor (321) on both sides of the gap to form a continuous conductive path. The impedance value of the center impedance element (322) is higher than the average characteristic impedance of the open ring radiator (3). The impedance value of the center impedance element (322) is adjusted according to the front-to-back ratio and radiation efficiency of the antenna.

7. The ultra-wideband tapered slot line composite antenna for electromagnetic compatibility testing according to claim 6, characterized in that, A power supply inner hole (103) is provided between the uniform groove line (130) and the circular hole (102) of the groove line radiator (1). The inner conductor of the coaxial connector (2) passes through the power supply inner hole (103) and crosses the uniform groove line (130). It is connected to the lower radiating arm (101) at the edge of the gap of the uniform groove line (130). The outer conductor of the coaxial connector (2) is connected to the left side wall of the groove line radiator (1).

8. The ultra-wideband tapered slot line composite antenna for electromagnetic compatibility testing according to claim 7, characterized in that, The diameter of the feed hole (103) is larger than the inner conductor diameter of the coaxial connector (2). By adjusting the radial dimension ratio of the two, impedance matching between the port and the coaxial connector (2) can be achieved.

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