A broadband transverse electromagnetic horn antenna mountable on a surface of a metal cylinder
By installing four independent transverse electromagnetic horn antennas on the surface of a metal cylinder and connecting them with nylon isolation pillars and inverted L-shaped grounding wires, combined with a gradient curve and top cover structure, the problems of bandwidth reduction and radiation pattern distortion of broadband antennas on the surface of a metal cylinder are solved, achieving stable radiation and good radiation pattern in the 1GHz to 16GHz frequency band, suitable for UWB communication and EMC testing.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SOUTHEAST UNIV
- Filing Date
- 2022-11-23
- Publication Date
- 2026-05-15
AI Technical Summary
In the prior art, when broadband antennas are installed on the surface of a metal column, their bandwidth is narrow and their radiation pattern is severely distorted, making it difficult to maintain good radiation performance on the surface of a metal column.
Design a broadband transverse electromagnetic horn antenna that can be mounted on the surface of a metal cylinder. It employs four independent transverse electromagnetic horn antennas, which are securely connected by nylon isolation pillars and inverted L-shaped grounding wires. Combined with a metal gradient curve and a top cover structure, a transmission line system is formed to improve bandwidth and maintain pattern stability.
It achieves stable radiation in the 1GHz to 16GHz frequency band with a VSWR of less than 2 and a good radiation pattern, making it suitable for UWB communication systems and EMC testing, and overcoming the problems of bandwidth reduction and radiation pattern distortion.
Smart Images
Figure CN115775975B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a broadband transverse electromagnetic horn antenna that can be mounted on the surface of a metal cylinder, belonging to the field of broadband antenna technology. Background Technology
[0002] Depending on the system and application, ultra-wideband antennas can be divided into three categories: The first is full-band antennas, which have a wide bandwidth and are frequently used in ground-penetrating radars (GRRs), antenna pattern testing, electromagnetic compatibility (EMC), etc. Their design goal is to cover as many frequency bands as possible. The second is multi-narrowband antennas, which are designed as scanning antennas or smart antennas to receive and detect narrowband signals within a wide frequency band. Their design goal is also to cover many frequency bands, but only a very small segment of the band is used at any given time. The third is modern ultra-wideband antennas, operating in the 3.1 GHz to 10.6 GHz communication band designated by the FCC. They are used in ultra-wideband (UWB) communication systems. Ultra-wideband (UWB) technology is a short-range wireless communication method. Its transmission distance is typically within 10 meters, using bandwidths above 1 GHz. UWB does not use a carrier wave but instead uses short pulses to transmit data; therefore, it occupies a wide spectrum range, making it suitable for high-speed, short-range wireless personal communication.
[0003] UWB technology has the following characteristics: excellent coexistence, because its transmission power is very low and there is less interference between devices, so they can share frequencies; high transmission rate, because the UWB communication system has a wide bandwidth, so its transmission rate exceeds that of current traditional transmission technologies; and strong anti-interference capability, because when the UWB system transmits, the energy is distributed over a wider frequency band, which allows it to recover the transmitted signal more accurately than narrowband systems, resulting in stronger anti-interference capability.
[0004] In UWB systems, ultra-wideband antennas are a crucial component. Commonly used UWB antennas include monopole antennas, log-periodic antennas, and broadband horn antennas. However, UWB systems sometimes involve placing antennas on metal surfaces. When a broadband antenna is placed on a metal cylinder, the coupling between the antenna and the cylinder degrades the antenna's standing wave ratio (SWR) and radiation pattern performance. In this scenario, broadband horn antennas can be used, but their bandwidth typically doesn't exceed 10:1; monopole antennas can be used, but their radiation patterns become cluttered at high frequencies; surface wave antennas can also be used, but their bandwidth is difficult to exceed 5:1. Therefore, designing an antenna with a bandwidth exceeding 10:1 while maintaining a stable radiation pattern within that bandwidth is a problem that needs to be solved in this context. Summary of the Invention
[0005] Technical Problem: The purpose of this invention is to overcome the problems of narrow bandwidth and radiation pattern distortion of existing antennas, and to provide a design method for a transverse electromagnetic horn antenna that can be mounted on the surface of a metal column, so that it can maintain a good radiation pattern and simple structure while having a wide bandwidth, thereby improving the practicality of the antenna.
[0006] Technical solution: In order to achieve the above objectives, the present invention provides the following technical solution.
[0007] A broadband transverse electromagnetic horn antenna that can be mounted on the surface of a metal cylinder is characterized by comprising a metal cylindrical carrier and four transverse electromagnetic horn antennas mounted on the cylindrical surface. These four antennas have identical structures and operate independently. The transverse electromagnetic horn antennas and the cylinder are securely connected by two nylon insulating posts and an inverted L-shaped grounding wire of the transverse electromagnetic horn antennas.
[0008] Furthermore, each transverse electromagnetic horn antenna of the present invention includes a radiating structure, a ridge structure, a coaxial probe, and an inverted L-shaped grounding wire. The radiating structure is used for broadband energy radiation, the ridge structure is used to protect the transmission of high-frequency energy and extend the antenna's operating bandwidth, and the inverted L-shaped grounding wire is used for connecting the antenna structure and the metal cylindrical carrier. The coaxial probe passes through the ridge structure and the tapered structure for antenna feeding. The radiating structure consists of a tapered curve and a top cover plate.
[0009] Furthermore, the bottom of the inverted L-shaped grounding wire is fitted with a threaded hole for fastening to the metal cylindrical carrier.
[0010] Furthermore, the cylindrical metal carrier is equipped with 16 threaded holes for securing 8 nylon isolation posts and 4 coaxial connectors.
[0011] Furthermore, each transverse electromagnetic horn antenna has three threaded holes on its inverted L-shaped structure for connection to the cylindrical metal carrier.
[0012] The performance specifications of the broadband transverse electromagnetic horn antenna that can be mounted on the surface of a metal cylinder provided by this invention are as follows:
[0013] Frequency band: 1GHz~16GHz; Polarization: linear polarization; Radiation direction: directional; Voltage standing wave ratio: 2 (1GHz~16GHz); Antenna gain: 4dBi~11dBi; Nominal impedance: 50Ω.
[0014] Beneficial Effects: Compared to existing technologies, the antenna provided by this invention has a wide operating frequency band, good directivity, and is easy to install when mounted on the surface of a metal cylinder. It can be used in UWB communication systems, EMC testing, and radio spectrum detection. The ridge structure and the antenna's radiating structure form a transmission line structure, along which electromagnetic waves propagate, significantly improving the antenna's bandwidth. The radiating structure consists of a metal gradient curve and a top cover plate. When electromagnetic waves pass through this gradient structure, energy can be smoothly radiated to complete the antenna's radiation function. The top cover plate can lower the antenna's low-frequency operating point because the current path is increased and low-frequency electromagnetic waves are conducted to the top cover plate for radiation. Experimental results show that the antenna of this invention can achieve a standing wave ratio of less than 2 from 1 GHz to 16 GHz. Within the operating frequency band, the antenna has a good radiation pattern and a simple structure, effectively overcoming the bandwidth reduction and radiation pattern distortion problems that exist when broadband antennas are mounted on the surface of a metal cylinder. Attached Figure Description
[0015] Figure 1 This is an assembly diagram of the structure of the present invention.
[0016] Figure 2 This is a top view of the structure of the present invention.
[0017] Figure 3 This is a diagram of the antenna structure of the present invention.
[0018] Figure 4 This is a schematic diagram of the antenna fabrication model of the present invention.
[0019] Figure 5 This is a comparison chart of antenna standing wave test and simulation of the present invention.
[0020] Figure 6 This is a comparison diagram of antenna coupling test and simulation of the present invention.
[0021] Figure 7 This is a comparison chart of antenna gain testing and simulation results for the present invention.
[0022] Figure 8 The gain patterns of the antenna of the present invention are obtained from testing and simulation in the E-plane and H-plane at 1 GHz.
[0023] Figure 9 The gain patterns of the antenna of the present invention at 4 GHz are obtained from testing and simulation in the E-plane and H-plane.
[0024] Figure 10 The gain patterns of the antenna of the present invention at 8 GHz are obtained from testing and simulation in the E-plane and H-plane.
[0025] Figure 11 The gain patterns of the antenna of the present invention are obtained from testing and simulation in the E-plane and H-plane at 12 GHz.
[0026] Figure 12 The gain patterns of the antenna of the present invention are obtained from testing and simulation in the E-plane and H-plane at 16 GHz.
[0027] Reference numerals in the attached figures: 1 is the metal cylindrical body of the carrier; 2 is the horizontal electromagnetic horn antenna A; 3 is the horizontal electromagnetic horn antenna B; 4 is the horizontal electromagnetic horn antenna C; 5 is the horizontal electromagnetic horn antenna D; 6 is the nylon isolation column; 7 is the reinforcing rib A; 8 is the reinforcing rib B; 9 is the coaxial probe A; 10 is the coaxial probe B; 11 is the coaxial probe C; 12 is the coaxial probe D; 13 is the inverted L-shaped grounding structure; 14 is the radiating part of the horizontal electromagnetic horn antenna; 15 is the ridge; 16 is the screw used for installation; 17 is the metal gradient curve; 18 is the top cover plate. Detailed Implementation
[0028] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.
[0029] Figure 1 This is a structural assembly drawing of the invention. Figure 2 This is a top view of the structure of the invention. Specifically, the model includes: a metal cylindrical mounting carrier 1, horizontal electromagnetic horn antennas A 2, B 3, C 4, and D 5, and coaxial probes A 9, B 10, C 11, and D 12. The antennas are securely connected to the metal cylindrical carrier 1 via nylon insulating posts 6 and screws 16. The coaxial probes pass through the ridge structure 15 and connect to the radiating portion 14 of the horizontal electromagnetic horn antennas. The four antennas are symmetrically placed on the carrier, with equal spacing between each pair of antennas. After determining the mounting position of one antenna, the positions of the other three antennas can be determined by rotating the first antenna 90 degrees, 180 degrees, and 270 degrees around the center point of the cylindrical surface.
[0030] Specifically, the metal cylinder 1 has reinforcing ribs A 7 and B 8 inside to enhance its structural strength. In practical applications, these two structures can be removed if the metal cylinder 1 has sufficient strength. The surface of the metal cylinder 1 has 16 threaded holes for mounting the nylon isolation post 6 and the coaxial connector.
[0031] Figure 3This is a detailed diagram of a horizontal electromagnetic horn antenna. The horizontal electromagnetic horn structure consists of an inverted L-shaped grounding structure 13, a radiating section 14, and a ridge 15. The antenna's working principle is as follows: a coaxial probe 9 passes through the ridge structure 15, where the coaxial probe 9 is connected to the radiating section 14 of the horizontal electromagnetic horn antenna. At this time, the ridge structure 15 and the antenna's radiating structure 14 form a transmission line structure, and electromagnetic waves propagate forward along this two-line system. The radiating structure 14 mainly consists of a metal gradient curve 17 and a top cover plate 18. The metal gradient curve 17 contains a gradient curve section, which can be set as a multi-stage curve, an exponential curve, etc. When electromagnetic waves pass through this gradient structure 17, energy can be smoothly radiated to complete the antenna's radiation function. The radiating structure 14 also includes a top cover plate 18. This structure can lower the antenna's low-frequency operating point because the current path is increased and low-frequency electromagnetic waves are conducted to the top cover plate 18 for radiation. The shape of the top cover plate 18 is a single-stage curve. The horizontal electromagnetic horn antenna also includes an inverted L-shaped structure 13 for connection with the metal cylindrical body 1.
[0032] Before processing, in order to verify the performance of the antenna, CST full-wave simulation software was first used to simulate the standing wave and radiation performance of the antenna. After the performance met the expectations, the antenna was processed.
[0033] Figure 4 The image shows the actual fabricated antenna. First, the antenna's standing wave ratio (VSWR) was tested. Figure 5 The standing wave ratio (SWR) curves from both the actual test and simulation are presented. The figures show that the simulated and tested structures are largely consistent, and the antenna SWR meets the requirement of being less than 2 from 1 GHz to 16 GHz. Figure 6 The coupling between the antennas was tested. The coupling was between -20dB and -30dB from 1GHz to 3GHz, and less than -30dB above 3GHz. The antenna coupling was relatively small in the frequency band in which the antennas were operating.
[0034] Figure 7 The measured and simulated gain curves of the antenna are presented. It can be seen that the gain curve of the fabricated antenna is largely consistent with the simulation, but it is lower than that of the simulated antenna from 5GHz to 19GHz. This may be due to the high surface resistance of the antenna, fabrication errors, installation errors, and test system errors.
[0035] Figure 8 , Figure 9 , Figure 10 , Figure 11 and Figure 12The test and simulation results of the antenna gain patterns at 1 GHz, 4 GHz, 8 GHz, 12 GHz, and 16 GHz are compared. The shape of the radiation patterns is largely consistent between the test and simulation results. It can be observed that the radiation pattern in the E-plane has a point pointing upwards and lacks symmetry, while the radiation pattern in the H-plane is more symmetrical. The main reason for this is the antenna's symmetry; the antenna structure is symmetrical in the H-plane, but the presence of the metal cylinder 1 in the E-plane disrupts the antenna's symmetry, resulting in an asymmetrical radiation pattern in the E-plane.
[0036] This invention addresses the performance degradation problem of broadband antennas mounted on the surface of a metal cylinder by proposing a broadband transverse electromagnetic horn antenna that can be mounted on such a surface. Four transverse electromagnetic horn wires are mounted on a metal cylinder, and the antenna's performance is verified using simulation software CST and physical fabrication methods. Experimental results show that the designed antenna can achieve a VSWR of less than 2 from 1 GHz to 16 GHz, exhibits a good radiation pattern within its operating frequency band, and its simple structure effectively overcomes the bandwidth reduction and radiation pattern distortion problems inherent in broadband antennas mounted on metal cylinder surfaces. This design has certain application value in UWB communication systems, EMC testing, and radio spectrum detection.
Claims
1. A broadband transverse electromagnetic horn antenna that can be mounted on the surface of a metal cylinder, characterized in that, It includes a metal cylindrical carrier and several transverse electromagnetic horn antennas mounted on the surface of the cylinder. Each transverse electromagnetic horn antenna is completely identical and operates independently. The transverse electromagnetic horn antenna includes a radiating structure, a ridge structure, a coaxial probe, and an inverted L-shaped grounding wire. The radiating structure is used for broadband energy radiation, the ridge structure is used to protect the transmission of high-frequency energy and extend the working bandwidth of the antenna, and the inverted L-shaped grounding wire is used for the connection between the antenna structure and the metal cylindrical carrier. The coaxial probe passes through the ridge structure and the radiating structure to connect and is used for antenna feeding; The ridge structure is on the surface of the cylinder; The radial and ridge structures form a transmission line structure; The radiation structure includes a metal gradient curve and an upper cover plate; the metal gradient curve includes a gradient curve section, through which the energy of electromagnetic waves can be successfully radiated to complete the radiation function of the antenna. The top cover can lower the low-frequency operating point of the antenna because the current path is increased and low-frequency electromagnetic waves are conducted to the top cover for radiation. The gradient curve is a polynomial curve or an exponential curve; the shape of the upper cover plate is a linear curve.
2. A broadband transverse electromagnetic horn antenna that can be mounted on the surface of a metal cylinder according to claim 1, characterized in that, The horizontal electromagnetic horn antenna is fastened to the metal cylindrical body by nylon insulating posts and screws.
3. A broadband transverse electromagnetic horn antenna that can be mounted on the surface of a metal cylinder according to claim 1, characterized in that, The metal cylindrical carrier has reinforcing ribs inside to enhance its structural strength.