A substrate integrated waveguide slot array capable of realizing two-dimensional single-pulse function

Abstract

The application relates to a substrate integrated waveguide slot array capable of realizing two-dimensional single-pulse functions, which is composed of a left slot array, a right slot array and an inner calibration network. The left slot array and the right slot array both adopt substrate integrated waveguide longitudinal slot radiation arrays, and the inner calibration network is composed of two coupling substrate waveguides which are vertically arranged at the ends of the left slot array and the right slot array. The left slot array and the right slot array are mirror arranged along the y-axis, and a novel power distribution converter is introduced at the middle feeding positions of the left slot array and the right slot array. The novel power distribution converter can realize the conversion between the substrate integrated waveguide and the coaxial connector, and can also realize the unequal power output of the two side ports. The design method can effectively reduce the processing difficulty of the antenna, improve the working bandwidth of the array antenna, and provides a basis for realizing a low-cost, low-weight and high-integration two-dimensional single-pulse active phased array antenna.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of radar antenna, in particular to a substrate integrated waveguide active phased array antenna, mainly applied to the active phased array radar capable of realizing two-dimensional monopulse function. BACKGROUND

[0002] Compared with the traditional rectangular metal waveguide, the substrate integrated waveguide also has good propagation characteristics, and the structure is easy to integrate, greatly reducing the size, weight and price of the original array antenna based on the waveguide, and enhancing the repeatability and reliability in the manufacturing process. As a substitute for the traditional metal waveguide slot array antenna, the substrate integrated waveguide slot array antenna has important practical significance and broad application prospect. In 1997, the initial form of substrate integrated waveguide slot array was proposed by using a metal via array to replace the wide side of the waveguide, and then etching a slot on the narrow side.

[0003] In 2004, Li Yan et al. successfully realized the resonant substrate integrated waveguide array antenna in the form of wide longitudinal slot, and used a tapered line form in the design of SIW-microstrip conversion, which gradually changed to a 50-ohm microstrip transmission line. Subsequently, domestic SIW-based slot array antennas basically adopted similar forms for research and development. Two-dimensional monopulse antenna has the advantage of improving target measurement accuracy. Two-dimensional monopulse can form sum and difference beams in the azimuth and elevation planes, but few substrate integrated waveguide slot arrays can realize two-dimensional sum and difference beams in the current papers, patents, etc. To realize two-dimensional sum and difference beams, a small-size unequal power divider capable of being placed in the center of the SIW is first designed. Most of the currently published microstrip-substrate integrated waveguide feed conversion converters can only be used to design substrate integrated waveguide resonant slot arrays fed at one end. When the relative permittivity of the filling medium changes, the SIW width changes or the frequency deviates, the change of the substrate integrated waveguide wavelength will cause the distance between the slot radiation units to be greater than or less than 0.5 times the guided wave wavelength, thereby causing the beam pointing angle of the array to change and the sidelobe level to deteriorate, which cannot be used to realize the H-plane sum and difference beams of the substrate integrated waveguide. SUMMARY

[0004] Technical problems to be solved

[0005] In order to avoid the shortcomings of the prior art, the present application provides a substrate integrated waveguide slot array capable of realizing two-dimensional monopulse function.

[0006] Technical scheme

[0007] A substrate integrated waveguide slot array capable of realizing two-dimensional single pulse function, characterized by comprising a left slot array, a right slot array and an inner calibration network, the left slot array and the right slot array adopt substrate integrated waveguide longitudinal slot radiation units, and the inner calibration network is composed of two coupled substrate integrated waveguides vertically arranged at the ends of the left slot array and the right slot array.

[0008] The left slot array and the right slot array are provided with a novel unequal power distribution converter in the middle of the array, so that the center same-layer feeding of the substrate integrated waveguide can be realized, and the unequal power distribution of the two side ports can also be realized; the power distribution converter is connected with the upper metal layer through the probe of the coaxial connector from the back of the substrate integrated waveguide linear array center position, and the left metal inductive column and the right metal inductive column are distributed on the two sides of the coaxial connector, and the power distribution ratio of the two branch ports can be controlled by adjusting the positions of the two metal inductive columns.

[0009] The left slot array and the right slot array are mirror arranged along the y-axis, and the whole radiation array surface can be divided into four quadrants, and the two-dimensional sum and difference beams can be realized through the transceiver assembly and the two-dimensional single pulse network.

[0010] The inner core of the coaxial connector in the inner calibration network penetrates the lower layer metal of the calibration substrate integrated waveguide and is connected with the upper metal layer, and the impedance matching of the feeding end can be realized by adjusting the position of the inner core of the coaxial connector relative to the calibration substrate integrated waveguide; the other end of the calibration substrate integrated waveguide is a residual power absorption end, which is connected with a 100-ohm absorption resistor after being converted into a 100-ohm microstrip transmission line through a 90° SIW bending and a SIW-microstrip conversion.

[0011] The left slot array and the right slot array each contain 10 linear arrays.

[0012] Advantages

[0013] The substrate integrated waveguide slot array capable of realizing two-dimensional single pulse function provided by the application adopts a wide edge longitudinal slot form, is divided into a left slot array and a right slot array, and a novel power distribution converter is introduced in the middle feeding position of the linear array, so that the same-layer small-size center feeding and unequal power distribution of the substrate integrated waveguide slot array can be realized, the processing difficulty of the antenna is reduced, and the two-dimensional single pulse active phased array antenna with low cost, low weight and high integration degree can be realized.

[0014] Compared with the prior art, the application has the following advantages:

[0015] 1. The antenna array surface of the application adopts a substrate integrated waveguide wide edge longitudinal slot array, the left and right array centers are directly fed by coaxial connectors, and two-dimensional sum and difference beams can be realized.

[0016] 2. The power distribution converter is small in size, located in the center of the array, and can realize SIW-coaxial small size conversion and arbitrary power distribution ratio output at the same time;

[0017] 3. The calibration detection network and the antenna array are printed on the same PCB board, simple in structure, and capable of realizing calibration detection function of each transceiving channel. BRIEF DESCRIPTION OF DRAWINGS

[0018] The accompanying drawings are included to provide a further understanding of the application, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the application and, together with the description, serve to explain the principles of the application. In the drawings:

[0019] Figure 1 A plan view of an antenna array according to an embodiment of the application;

[0020] Figure 2 A plan view of a left slot array according to an embodiment of the application;

[0021] Figure 3 An azimuth plane (H-plane) simulation pattern of an antenna array according to an embodiment of the application;

[0022] Figure 4 A measured azimuth plane (E-plane) center frequency ±40° range scan sum and difference patterns of an antenna array according to an embodiment of the application. DETAILED DESCRIPTION

[0023] In order to make the objects, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and should not be used to limit the present application. In addition, the technical features involved in the various embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0024] The application provides a two-dimensional single-pulse function realized substrate integrated waveguide slot array, which is composed of a left slot array 1, a right slot array 2 and an inner calibration network 3, the left slot array 1 and the right slot array 2 are both substrate integrated waveguide longitudinal slot radiation arrays, the inner calibration network 3 is composed of two coupling substrate waveguides which are vertically arranged at the ends of the left slot array and the right slot array and are integrated with the antenna array in the same plane. The left slot array and the right slot array are mirror arranged along the y axis, the whole radiation array surface can be divided into four quadrants, and through a transceiver assembly and a two-dimensional single-pulse network, a sum beam, an azimuth difference beam and an elevation beam can be formed, so that the two-dimensional single-pulse function of the radar is realized. A novel small-size power distribution converter 11 is arranged at the middle feeding position of the left slot array 1 and the right slot array 2, which can realize the conversion between the substrate integrated waveguide and the coaxial connector and also can realize the unequal power output of the two side ports. The probe 111 of the coaxial connector in the power distribution converter 11 is connected with the upper metal layer through the substrate integrated waveguide linear array center position from the back, the left metal inductive column 112 and the right metal inductive column 113 are distributed on the two sides of the coaxial connector, and the power distribution ratio of the two branch ports can be controlled by adjusting the position of the metal inductive column. The design method can form the array H plane and the difference beam while effectively reducing the design and processing difficulty of the antenna, and provides a basis for realizing the two-dimensional single-pulse active phased array antenna with low cost, low weight and high integration.

[0025] In order for those skilled in the art to better understand the application, the application will be described in detail below in combination with specific examples.

[0026] Reference Figure 1The antenna array of the application comprises 12 left slot arrays 1, 12 right slot arrays 2 and an inner calibration network 3. The left slot array 1 and the right slot array 2 each adopt a substrate integrated waveguide longitudinal slot radiating unit, and each linear array has 10 units. The designed antenna linear array works at 9.7GHz, so the substrate integrated waveguide adopts a polytetrafluoroethylene dielectric plate with a dielectric constant of 2.2 and a thickness of 1.0mm, the waveguide width is selected as 13.5mm, the pitch of the metalized via array is 1.8mm, and the diameter is 1mm. The left slot array 1 and the right slot array 2 are mirror arranged along the y axis, and the two antenna linear arrays jointly form a-25dB Taylor amplitude weighting in the antenna H plane (i.e. the azimuth plane). The entire antenna array is divided into four quadrants by the x axis and the y axis, and two-dimensional sum and difference beams can be realized through a transceiver assembly and a two-dimensional monopulse network. The two coupled substrate integrated waveguides of the inner calibration network 3 are vertically placed at the ends of the left slot array and the right slot array, and are integrated and designed on the same plane with the antenna array. The width of the calibration substrate integrated waveguide 34 is 13.0mm, the pitch of the metalized via array is 1.8mm, and the diameter is 1mm; the inner core 31 of the coaxial connector in the inner calibration network 3 passes through the lower layer metal of the calibration substrate integrated waveguide 34 and is connected with the upper layer metal, and the impedance matching of the feeding end can be realized by adjusting the position of the inner core 31 of the coaxial connector relative to the calibration substrate integrated waveguide 34; the other end of the calibration substrate integrated waveguide 34 is a residual power absorption end, which is connected with a 100-ohm absorption resistor after being converted into a 100-ohm microstrip transmission line through a 90°SIW bend 33 and a SIW-microstrip conversion 32. The waveguide short circuit end of the left slot array 1 and the right slot array 2 close to the inner calibration network 3 is short-circuited by removing a metalized via, so that part of the power in the linear array is coupled into the calibration substrate integrated waveguide 34, and the coupling degree of the linear array and the calibration substrate integrated waveguide 34 can be adjusted to the required level by adjusting the pitch of the metalized via, the coupling degree of the application is designed to be about-35dB, and the real-time calibration and detection function of the transceiver channel can be realized.

[0027] Referring to Figure 2A new type of power distribution converter 11 is used at the middle feed of the left and right slot arrays 1 and 2. The distribution converter 11 can realize the conversion function of coaxial-SIW, and can realize unequal power distribution on both sides of the feed. The converter is located on the same layer of the antenna array surface and basically does not occupy the size of the linear array. The probe 111 of the coaxial connector in the power distribution converter 11 passes through the center position of the substrate integrated waveguide linear array from the back and is connected with the upper metal layer. The left and right metal inductive columns 112 and 113 are distributed on both sides of the coaxial connector. By adjusting the position of the metalized inductive column, the power distribution ratio of the two branch ports can be controlled to meet the power distribution requirements of the radiation slots on both sides of the feed point, and then the low sidelobe of the antenna H plane (i.e. azimuth plane) and beam can be realized. The substrate integrated waveguide slot array designed by using the coaxial-SIW power distribution converter 11 can be realized by using only one layer of microstrip plate.

[0028] Referring to Figure 3 The simulation pattern of the antenna array surface azimuth plane (H plane) of the embodiment can form sum and difference patterns, and the maximum sidelobe of the sum beam is-21.7 dB, and the zero value depth of the difference beam is-36 dB.

[0029] Referring to Figure 4 The measured azimuth plane (E plane) center frequency ±40° range scanning and difference patterns of the embodiment. From the measured pattern, it can be seen that within the scanning range of ±40° of the center frequency, the pattern sidelobe level can reach 20 dB, and the zero depth of the difference pattern can reach more than 20 dB. The gain is only reduced by about 2.5 dB when scanning to 40 degrees, which can meet the normal use requirements of two-dimensional monopulse active phased array radar.

[0030] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto. Any skilled person in the art can easily think of various equivalent modifications or replacements within the technical range disclosed by the present application, and these modifications or replacements should be covered within the protection scope of the present application.

Claims

1. A substrate-integrated waveguide slot array capable of realizing two-dimensional single-pulse functionality, characterized in that... The array includes a left slit array (1), a right slit array (2), and an inner calibration network (3). The left slit array (1) and the right slit array (2) are made of substrate integrated waveguide longitudinal slit radiation units. The inner calibration network (3) consists of two coupled substrate integrated waveguides placed vertically at the ends of the left slit array (1) and the right slit array (2). A novel power distribution converter (11) with unequal power distribution is introduced in the middle of the left slit array (1) and the right slit array (2). This can realize the same-layer feeding of the center of the substrate integrated waveguide and the unequal power distribution of the two ports. The power distribution converter (11) is connected to the upper metal layer by the probe (111) of the coaxial connector passing through the center of the substrate integrated waveguide array from the back. The coaxial connector has left metal inductor pillars (112) and right metal inductor pillars (113) distributed on both sides. The two metal inductor pillars can be controlled by adjusting their positions. The power distribution ratio of the branch port; the left slot array (1) and the right slot array (2) are arranged in a mirror image along the y-axis. The entire radiation array can be divided into four quadrants. Two-dimensional sum and difference beams can be realized through the transceiver components and the two-dimensional single pulse network; the inner core (31) of the coaxial connector in the inner calibration network (3) passes through the lower metal layer of the calibration substrate integrated waveguide (34) and is connected to the upper metal layer. By adjusting the position of the inner core (31) of the coaxial connector relative to the calibration substrate integrated waveguide (34), the impedance matching of the feed end can be realized; the other end of the calibration substrate integrated waveguide (34) is the residual power absorption end. After passing through a 90° SIW bend (33), it is connected to a SIW-microstrip converter (32) to convert the substrate integrated waveguide into a 100-ohm microstrip transmission line and then connect it to a 100-ohm absorption resistor; the left slot array (1) and the right slot array (2) each contain 10 linear arrays.

Images