CN112216980B

CN112216980B - Full-aperture strong-coupling ultra-wideband symmetric dipole phased-array antenna

Info

Publication number: CN112216980B
Application number: CN202011090879.5A
Authority: CN
Inventors: 杨仕文; 杨佳琦; 陈益凯; 屈世伟
Original assignee: University of Electronic Science and Technology of China
Current assignee: University of Electronic Science and Technology of China
Priority date: 2020-10-13
Filing date: 2020-10-13
Publication date: 2021-05-14
Anticipated expiration: 2040-10-13
Also published as: CN112216980A

Abstract

The invention discloses a full-aperture strong-coupling ultra-wideband symmetric dipole phased-array antenna based on a strong coupling effect and a development method thereof. The antenna array simultaneously excites two mirror symmetry dipole units through a Wilkinson power dividing circuit, extension dipole units are adopted at ports at two edges of the array, the influence of a truncation effect in the x-axis direction is eliminated on the premise of not using a dummy element, the radiation aperture of the antenna is increased, the standing wave of the low-frequency band of the array is improved, a vertical metal wall is added at the edge of the array to replace the dummy element and serve as a support of a wide-angle impedance matching layer, and finally all ports of the antenna array feed electricity, so that the purposes of utilizing the full aperture of an antenna array surface and realizing higher aperture efficiency are achieved. The phased array antenna has a simple and stable structure, is convenient to process, can achieve an active standing wave less than 3 in a frequency band of 1-4GHz, and is particularly suitable for application platforms which need ultra-wide working frequency bands, low cost, small size and high efficiency.

Description

Full-aperture strong-coupling ultra-wideband symmetric dipole phased-array antenna

Technical Field

The invention belongs to the technical field of antenna engineering, and particularly relates to a full-aperture ultra-wideband phased array antenna based on a strong coupling effect and a development method thereof.

Background

The phased array technology has been paid attention to by its advantages of fast scanning speed, flexible lobe control, high functional integration level, etc. Due to the increasing demand for monitoring and tracking various aircrafts such as satellites, missiles, airplanes and other targets and the like, and in order to extract more effective information in increasingly complex environments, the radar is urgently required to have the functions of multiple functions, multiple targets, high data rate, high precision, interference resistance and the like. Modern phased array technology can search, identify and track nulls simultaneously, transmitting information at high data rates, and therefore phased array technology plays a significant role in modern radar and electronic warfare. The traditional phased array is often narrow in bandwidth, the whole equipment is complex, the size is large and heavy, and the maintenance is time-consuming and labor-consuming in the practical application process.

In recent years, a novel broadband array antenna technology, namely a broadband array antenna technology based on a strong coupling effect, is proposed in the field of antenna research. Researches show that the impedance characteristics of the array elements can be changed smoothly when the frequency is changed due to the strong coupling effect among the antenna units, so that a wider impedance bandwidth can be realized through simple matching. The strong coupling structure is added, so that the design of additional structures such as a decoupling network and the like can be omitted, and the aim of simplifying the array structure is fulfilled. Moreover, compared with the traditional phased array antenna, the strong mutual coupling phased array is smaller in size and more compact in arrangement among units, so that the strong mutual coupling phased array can be more beneficial to conformal design. The antenna array with the closely-arranged units cannot greatly influence the performance of the whole array when a certain unit fails, so that the strong mutual coupling phased array has stronger adaptability to severe environments. It is these advantages that make the strong mutual coupling phased array have wider prospect in practical application, especially military application. Such as the "wideband phased array antenna and its related art" proposed in US patent No. US 6512487. In this patent, a capacitive coupling component is introduced by interdigitation between adjacent dipoles in close proximity, which compensates for the inherent inductance component of the antenna dipoles and the inductance component of the antenna ground plane. However, the scheme needs to use more than two microwave dielectric layers, and generally requires that the dielectric layer serving as a wide-angle scanning matching layer has a thickness proportional to the operating wavelength, so that the scheme is inconvenient for further design of a low-profile light-weight broadband phased array antenna.

In chinese patent No. CN105846081, the applicant proposes a dual-polarized one-dimensional strong-coupling ultra-wideband wide-angle scanning phased array, and the horizontal and vertical gradually-changed extending parts on both sides of the vertical-polarized dipole of the antenna replace the traditional array element connected with a matching resistor as a dummy element, thereby improving the bandwidth level, avoiding the loss efficiency, and saving the space. However, this solution requires the printing of continuous circuits on two substrates perpendicular to each other, which makes the final antenna array difficult to process and connect, complex and unstable.

In the document "a planar ultra-wideband with wide-Angle scanning array loaded with a polarization-selective surface structure", the author adopts an amplitude attenuation excitation array scheme to eliminate the truncation effect, the excitation amplitude of the central port is maximum, and the excitation amplitude of the peripheral ports is continuously reduced.

The traditional strong coupling phased array antenna usually needs to arrange a large number of ports connected with matched loads at the periphery of an array feed port as dummy elements so as to reduce the active standing wave of units near the edge, so that the final array size is larger, the aperture utilization rate is low, and meanwhile, the cost is improved due to the introduction of a large number of dummy elements. Therefore, the method has very important practical engineering significance for researching a novel antenna structure so as to obtain the strongly-coupled phased array antenna with full-aperture radiation.

Disclosure of Invention

The invention aims to provide a full-aperture strong-coupling ultra-wideband symmetric dipole phased array antenna which adopts a parallel medium substrate excited by all ports, uses a thinner metamaterial wide-angle matching layer and realizes 1-4GHz ultra-wide band coverage and +/-60-degree wide-angle scanning, aiming at the problems that the traditional strong-coupling phased array antenna array needs to use a dummy element to reduce the influence of the truncation effect of edge ports, has large actual size of the array, and has low aperture utilization rate.

In order to achieve the purpose, the invention adopts the following technical scheme:

the antenna comprises two mirror symmetry dipole units, two parallel medium substrates, a wide-angle impedance matching layer, a Wilkinson power dividing circuit, a reflection floor and a coaxial connector. The mirror symmetry dipole unit comprises a dipole radiation patch, a ground coupling patch and a balun connected with the dipole radiation patch, wherein the dipole radiation patch is arranged on the parallel medium substrate; the wide-angle impedance matching layer comprises a substrate and a periodic open resonant ring metamaterial structure printed on the substrate; the Wilkinson power dividing circuit is connected with the bottom of the balun; the reflecting floor is a whole aluminum plate, and through holes are punched at the proper positions of the reflecting floor and the Wilkinson power dividing circuit for arranging microwave coaxial connectors.

Furthermore, an antenna array of 1x8 is manufactured according to the antenna unit, and dipoles at two edge ports of the array are extended dipole units, so that active standing waves of the array at a low frequency band are reduced. Meanwhile, the vertical metal wall is added at the edge of the array to replace the traditional array element connected with the matching resistor to serve as a dummy element and a support of the wide-angle impedance matching layer, finally all ports of the antenna array feed electricity, the array radiation aperture is consistent with the actual size, and the purposes of utilizing the full aperture of the antenna array surface and achieving higher aperture efficiency are achieved.

In summary, the antenna design scheme has the following advantages:

1. the antenna array with the scale of 1X8 simultaneously excites mirror symmetry dipole units through a Wilkinson power divider circuit, and the two edge ports of the array adopt extension type dipole units, so that the influence of truncation effect in the X-axis direction is eliminated on the premise of not using the traditional array element connected with matching resistors as a dummy element, the radiation aperture of the antenna is increased, and the low-frequency active standing wave of the array is improved; vertical metal walls (110) are added at the edges of the array to replace dummies and serve as supports of the wide-angle impedance matching layer, so that all ports of the antenna array are fed, the array radiation aperture is consistent with the actual size, and the purposes of full aperture utilization of the antenna array surface and higher aperture efficiency are achieved

2. The antenna radiation efficiency is high, and can reach more than 80% because no resistive material is used.

Drawings

Fig. 1 is a schematic diagram of a full aperture strong coupling ultra wide band symmetric dipole phased array antenna unit. The antenna comprises 100 a full-aperture strong-coupling ultra-wideband symmetric dipole phased-array antenna unit, 102 a periodic open resonant ring metamaterial structure and 103 a reflection floor. 104 is a wide angle impedance matching layer. 105. 106 are parallel dielectric substrates. 107 is a wilkinson power dividing circuit, and 108 is a coaxial connector.

Fig. 2 is a schematic diagram of two mirror symmetry dipole units 101 of the provided full aperture strong coupling ultra wide band symmetric dipole phased array antenna. The two mirror symmetry dipole units are symmetrical about a mirror plane located in the center of the unit, 101-1 and 101-2 are dipole radiation patches printed on a parallel medium substrate, 101-3 and 101-4 are ground coupling patches printed on the parallel medium substrate, 101-5 and 101-6 are baluns printed on the parallel medium substrate and connected with the dipole radiation patches, and meanwhile the bottoms of the baluns are connected with a Wilkinson power dividing circuit.

Fig. 3 is a 1X8 linear array of the elements of fig. 1 arranged along the y-axis.

Fig. 4 is a yoz plane view of the linear array of fig. 3, 109 is an extended dipole unit, and 110 is an array element with vertical metal walls added to the edges of the antenna array instead of the conventional matching resistor, which is used as a dummy element and is used as a support for a wide-angle impedance matching layer.

FIG. 5 shows the standing wave condition of the unit E surface of FIG. 1 by scanning at 0-60 degrees.

Fig. 6 shows the 0-degree scanning standing wave condition of all 8 ports of the 1X8 linear array.

Fig. 7 is a 0 degree main polarization and cross polarization pattern at 4GHz for 1X8 linear arrays.

Fig. 8 is a 45 degree scanning main polarization and cross polarization directional diagram at 4GHz of 1X8 linear arrays.

Fig. 9 shows the antenna efficiency in 0 degree scanning of 1X8 linear array.

Detailed Description

As shown in fig. 1 and 2, the present embodiment is based on a full aperture strong coupling ultra-wideband symmetric dipole phased-array antenna unit 100, and is composed of two mirror-symmetric dipole units 101, parallel

dielectric substrates

105 and 106, a wide-angle impedance matching layer 104, a wilkinson power dividing circuit 107, a reflection floor 103, and a coaxial connector 108. The parallel

dielectric substrates

105 and 106 adopt Taconnic TLY with the dielectric constant of 2.2. The mirror-symmetric dipole unit 101 comprises dipole radiation patches 101-1 and 101-2, ground coupling patches 101-3 and 101-4 and baluns 101-5 and 101-6 connected with the dipole radiation patches, which are printed on parallel

dielectric substrates

105 and 106, and circuits printed on the two parallel dielectric substrates are mirror-symmetric about a mirror surface. The bottom of the feed balun is connected with the Wilkinson power dividing circuit, a Marchand balun form is adopted, an open-circuit transmission line is connected with a short-circuit transmission line in parallel to form the feed balun for impedance matching, and the upper end of the balun is connected with a dipole radiation patch. The reflective floor 103 is a monolithic aluminum plate with through holes for mounting the coaxial connectors 108. The Wilkinson power dividing circuit substrate adopts Taconinc TLY and dielectric constant of 2.2, wherein one end of the Wilkinson power dividing circuit substrate is provided with a hole at a proper position and is connected with a coaxial connector, and the other two ends of the Wilkinson power dividing circuit substrate are respectively connected with the bottom of a balun to realize the feeding of an antenna. The wide-angle impedance matching layer 104 substrate adopts Taconnic TLX and dielectric constant of 2.55, the periodic opening resonant ring metamaterial structure 102 adopts an open circular ring design, and the purpose of expanding the antenna scanning angle in the frequency band is achieved by utilizing the periodic structure.

The whole height of the antenna is 0.42 high-frequency wavelength (31.8mm), the unit length is 74mm, the width is 37mm, and the antenna array mode is that the antenna units are continuously and tightly arranged along the y-axis direction to form 8 units. The dipole units of the ports at the two edges of the array are extension type dipole units 109, and vertical metal walls 110 are added at the edges of the array to replace the traditional array elements connected with matching resistors to be used as dummy elements and as supports of wide-angle impedance matching layers.

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the following embodiments and accompanying drawings.

The antenna elements in this embodiment are arranged in an array of 1X8 as shown in fig. 3. The dipole units of the ports at the two edges of the array are extension type dipole units, meanwhile, the vertical metal wall structure is used for replacing the traditional array elements connected with matching resistors at the edge of the array to serve as dummy elements, and the metal wall is used for supporting the impedance matching layer at the same time, as shown in fig. 4. According to an embodiment, the following data may be obtained using simulation software.

Fig. 5 shows the port corresponding standing wave characteristics of the embodiment in different scanning states of the E-plane, and it can be seen from the graph that the full-aperture strong-coupling ultra-wideband symmetric dipole phased array antenna unit of the embodiment has an impedance bandwidth greater than 4:1 in a scanning range of 60 degrees under the condition that the standing wave ratio requirement is less than 2.

Fig. 6 shows the standing wave condition of the 1X8 array provided by the present embodiment with all 8 ports. As can be seen from the figure, all the ports of the array can realize the standing wave less than 3 in the 1-4GHz frequency band, which shows that the array can realize good port matching under the premise of all the ports being excited.

Fig. 7 and 8 show the main polarization and cross polarization directional diagrams of the 1X8 array provided in this embodiment under the scanning conditions of 0 degree and 45 degrees in the 4GHz band, which shows that the array has a cross polarization performance greater than 30dB, and the main lobe beam and gain of the array directional diagram are normal, which shows that the full-aperture strong-coupling ultra-wideband symmetric dipole phased array antenna array processed by the above method can realize good radiation performance under the premise of full-aperture radiation and high aperture utilization rate.

Fig. 9 shows the 1X8 linear array provided by this embodiment, and the antenna efficiency in the 1-4GHz band is greater than 80%.

While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not limitation. Any feature disclosed in this specification may, unless stated otherwise, be replaced by alternative features serving equivalent or similar purposes; all of the disclosed features, or all of the method or process steps, may be combined in any combination, except combinations where mutually exclusive features or steps are present. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.

Claims

1. The full-aperture strong-coupling ultra-wideband symmetric dipole phased-array antenna array is characterized in that the antenna array is a 1X 8-scale antenna array manufactured by 8 antenna units, each antenna unit comprises two mirror-symmetric dipole units (101), two parallel dielectric substrates (105, 106), a wide-angle impedance matching layer (104) and a periodic open resonant ring metamaterial structure (102), a Wilkinson power divider circuit (107), a reflective floor (103) and a coaxial connector (108), wherein the periodic open resonant ring metamaterial structure (102), the Wilkinson power divider circuit (107), the reflective floor (103) and the coaxial connector are printed on the wide-angle impedance matching layer, and the mirror-symmetric dipole units comprise dipole radiation patches (101-1 and 101-2), grounding coupling patches (101-3 and 101-4) printed on the parallel dielectric substrates and baluns (101-5 and 101-6) connected with the dipole radiation patches; the antenna array with the scale of 1X8 simultaneously excites two mirror symmetry dipole units (101) through a Wilkinson power divider circuit (107), and the two edge ports of the array adopt extension type dipole units (109), so that the influence of truncation effect in the X-axis direction is eliminated on the premise of not using the traditional array element connected with a matching resistor as a dummy element, the radiation aperture of the antenna is increased, and the low-frequency active standing wave of the array is improved; the vertical metal wall (110) is added at the edge of the array to replace a dummy element and is used as a support of the wide-angle impedance matching layer, so that all ports of the whole antenna array are completely fed and excited to realize full-aperture radiation without influencing the radiation performance of the antenna, and compared with the traditional strong coupling antenna array using the dummy element, the antenna array realizes small size and low cost under the same gain condition.

2. The full aperture strongly coupled ultra wide band symmetric dipole phased array antenna array as claimed in claim 1, wherein the ground coupling patches (101-3, 101-4) printed on the parallel dielectric substrate are mutually coupled by the rectangular structure of the overlapping portion of the dipole radiating patches (101-1, 101-2) to provide a capacitive component between the dipole elements, satisfying the broadband characteristics of the antenna, while eliminating the common mode resonance due to the common mode current at a specific frequency point by grounding said coupling patches.