Millimeter wave monopulse filtering array antenna based on gap waveguide sum-difference network feed

Abstract

The invention discloses a millimeter wave monopulse filtering array antenna based on gap waveguide sum-difference network feed. The millimeter wave monopulse filtering array antenna comprises an SIW filtering antenna array and a GWG sum-difference network structure. The GWG sum-difference network structure is composed of three layers of metal plates with square metal pins, the space between every two adjacent layers of metal plates is filled with air, and every two adjacent layers of metal plates and the protruding pins form a GWG unit. The SIW filtering antenna array is composed of three layers of dielectric substrates and a layer of prepreg, the surfaces of the dielectric substrates are covered with metal layers, metal holes are loaded in the dielectric substrates and the prepreg to form resonant cavities of the antenna, and gaps are loaded in the metal layers to achieve coupling between the cavities and radiation of the antenna. The filtering antenna and the monopulse antenna are combined, the frequency selection characteristic of the filtering antenna and the high-precision target positioning characteristic of the monopulse antenna are achieved at the same time, and the advantages of being high in integration level and multifunctional are achieved.

Description

Technical Field

[0001] The present invention relates to the field of antenna technology, and in particular to a millimeter wave single pulse filter array antenna based on gap waveguide and difference network feeding. Background Art

[0002] Antennas are essential key components for wireless communication systems. They can complete the conversion between waveguide energy and electromagnetic field energy in space. With the development of modern wireless communications, antennas are developing towards multifunctionality, intelligence, miniaturization, and integration, and have produced a variety of types such as horn antennas, waveguide slot antennas, and microstrip antennas. They have also produced a variety of antenna forms with specific functions such as filter antennas and single pulse antennas to meet the increasingly diverse needs of current wireless communication systems.

[0003] A filtering antenna is an antenna with filtering function. This type of antenna can filter signals in a specific frequency range while receiving or transmitting signals, thereby improving the reliability of the system. In recent years, the development of wireless communication technology and modern integrated circuit technology has put forward requirements for multifunctionality, miniaturization, and integration of mobile terminal devices. In traditional RF front-ends, filters and antennas are designed independently, which have problems such as large physical size and high insertion loss. Therefore, microstrip antennas that have both radiation and filtering functions and the advantages of high efficiency, low loss, and miniaturization have been widely studied and applied.

[0004] The rapid development of rockets, missiles, artificial satellites and aerospace technology has put forward new requirements for the tracking speed, tracking accuracy, tracking distance and anti-interference ability of tracking radars. The tracking accuracy and speed of the original conical scanning system and sequential beam method cannot meet the increasingly high requirements, so the single pulse technology was born. The single pulse technology is a technology that obtains all the angular error information of the target through different beams of a single echo pulse. The essence of this technology is to add and subtract the echo signals received by several beams, obtain the distance information of the target in the sum branch, and obtain the off-axis information of the target in azimuth and elevation in the azimuth difference branch and the elevation difference branch respectively, so as to control the motor to move in the direction of reducing the error until the antenna axis is aligned with the target to achieve the purpose of tracking. Compared with the conical scanning radar, the radar using the single pulse system can quickly obtain the angular position information of the tracking target, and the tracking accuracy can be improved by 1 to 2 orders of magnitude, and the amplitude fluctuation of the echo signal will not have a significant impact on the measurement accuracy of the angular coordinates. The single pulse radar antenna has both precise positioning capability and rapid response capability. Today, as the speed of radar tracking targets increases day by day, it has received more and more attention.

[0005] The development direction of wireless communication equipment is portability and multifunctionality. Integrating multiple functions in one component can not only reduce the size of the device, but also reduce the energy loss during transmission. Therefore, it is of practical significance to combine the filtering antenna unit with the single pulse feeding network to design a single pulse antenna with filtering function. Summary of the invention

[0006] The purpose of the present invention is to propose a millimeter-wave single-pulse filter array antenna based on gap waveguide and difference network feeding, which has the advantages of high precision and high integration and can meet the needs of communication and detection systems for multifunctional and highly integrated antennas.

[0007] In order to achieve the above technical objectives, the technical solution adopted by the present invention is:

[0008] A millimeter wave single pulse filter array antenna based on gap waveguide sum difference network feeding, the millimeter wave single pulse filter array antenna includes a SIW filter antenna array composed of metal vias and metal layer slits loaded on a microstrip multilayer board structure and a GWG sum difference network structure composed of a metal plate with square pins;

[0009] The GWG sum-difference network structure is composed of three layers of metal plates with square metal pins, the space between two adjacent layers of metal plates is filled with air, the two adjacent layers of metal plates and the protruding pins constitute a GWG unit, and the electromagnetic wave is transmitted in the waveguide structure surrounded by the pins; after the energy is fed from the sum port or the difference port, it passes through the two-layer feeding network and is coupled into the SIW filter antenna array through the slots loaded on the surface of the metal plate;

[0010] The SIW filter antenna array is composed of three dielectric substrates with metal layers on the surface and a prepreg. Metal holes are loaded in the dielectric substrate and the prepreg to form the resonant cavity of the antenna. Slots are loaded on the metal layer to achieve coupling between cavities and radiation of the antenna. Energy is coupled into the cavity through the slots loaded on the metal layer on the lower surface of the lowest dielectric substrate, and after being transmitted through the resonant cavity, it is radiated into the free space through the slots loaded on the metal layer on the upper surface of the highest dielectric substrate.

[0011] Furthermore, the operating frequencies of the SIW filter antenna array and the GWG sum-difference network structure match, and both operate in the millimeter wave frequency band.

[0012] Furthermore, the gap loaded by the top metal plate corresponds one-to-one to the gap loaded by the metal layer below the bottom dielectric substrate, and the size of the gap loaded by the top metal plate is larger than the size of the gap loaded by the metal layer below the bottom dielectric substrate.

[0013] Furthermore, the SIW filtering antenna array is formed by stacking a first dielectric substrate, a prepreg, a second dielectric substrate and a third dielectric substrate, wherein the surfaces of the first dielectric substrate, the second dielectric substrate and the third dielectric substrate are covered with a metal layer; the first metal via passes through the first dielectric substrate, the prepreg and the second dielectric substrate, and together with the metal layers on the upper and lower surfaces of the first dielectric substrate and the second substrate, constitute a secondary resonant cavity and a tertiary resonant cavity of the antenna; the second metal via is located in the third dielectric substrate, and together with the metal layers on the upper and lower surfaces of the third dielectric substrate, constitutes a feeding path and a primary resonant cavity of the antenna;

[0014] Energy is coupled into the cavity through the gap loaded on the metal layer on the lower surface of the third dielectric substrate, and after being transmitted in the feeding path and the primary resonant cavity composed of the third dielectric substrate and the metal layers and metal vias on its upper and lower surfaces, it enters the secondary resonant cavity composed of the second dielectric substrate and the metal layers and metal holes on its upper and lower surfaces through the coupling gap loaded on the metal layer on the upper surface of the third dielectric substrate, and then enters the tertiary resonant cavity composed of the first dielectric substrate and the metal holes on its upper and lower surfaces through the coupling gap loaded on the metal layer on the upper surface of the second dielectric substrate and the metal layer on the lower surface of the first dielectric substrate, and finally radiates into the free space through the gap loaded on the metal layer on the upper surface of the first dielectric substrate.

[0015] Furthermore, the SIW filter antenna array is formed by connecting 32 antenna units in series in a 2×16 layout.

[0016] Furthermore, the metal layer on the upper surface of the first dielectric substrate is an antenna radiation layer, and a plurality of slots are arranged above the first dielectric substrate, and every two slots constitute a radiation unit of the antenna, and 32 radiation units are arranged in a 2×16 layout to form an antenna array;

[0017] The metal layer on the lower surface of the first dielectric substrate and the metal layer on the upper surface of the second dielectric substrate are first coupling slot layers, and electromagnetic energy enters the third-level resonant cavity from the secondary resonant cavity through the first coupling slots; the first coupling slots are arranged in a 2×16 layout;

[0018] The metal layer on the lower surface of the second dielectric substrate is a second coupling slot layer, and electromagnetic energy enters the secondary resonant cavity from the primary resonant cavity through the second coupling slots, and the second coupling slots are arranged in a 2×16 layout;

[0019] The metal layer on the lower surface of the third dielectric substrate is a third coupling slot layer, and electromagnetic energy enters the SIW feeding structure and the primary resonant cavity at the bottom layer of the SIW filtering antenna array from the GWG sum difference network structure through the third coupling slots, and the third coupling slots are arranged in a 2×16 layout; wherein the third coupling slots are arranged obliquely, and the direction is counterclockwise or clockwise rotating at a preset angle based on the x-axis direction, and the rotation directions of adjacent slots in the y-axis direction are opposite, so that the electromagnetic energy input to the antenna unit is in phase, and the rotation directions of adjacent slots in the x-axis direction are the same.

[0020] Furthermore, the GWG sum-difference network structure includes a first metal plate with square metal pins, a second metal plate, and a third metal plate stacked together. The square pins on the lower surface of the first metal plate and the square pins on the upper surface of the second metal plate constitute an upper GWG sum-difference network, and the square pins on the lower surface of the second metal plate and the square pins on the upper surface of the third metal plate constitute a lower GWG sum-difference network; the two layers of metal plates are filled with air; there are two input ports of sum and difference in the lower GWG sum-difference network, and after energy is fed into the sum port or the difference port, it passes through two layers of feeding networks and is coupled into the microstrip antenna array through the gap loaded on the upper surface of the first metal plate.

[0021] Further, the GWG and difference network structure includes a middle-upper layer transmission structure and a middle-lower layer transmission structure;

[0022] The middle and upper transmission structure is divided into two symmetrical upper and lower parts, each of which consists of a T-shaped power splitter structure and an angle structure; the sum port coupling slot is located at the tail of the angle, and the difference port coupling slot is located in the middle of the T-shaped power splitter; after the energy is coupled into the upper layer by the lower transmission structure, it passes through the T-shaped power splitter and enters the antenna array through the slots on the metal layer below the first metal plate and the lowest dielectric substrate;

[0023] The middle and lower transmission structure is divided into two parts, each of which has an input port, the left side of which is a sum port and the right side is a difference port; after the energy is input from the sum / difference port, it enters the upper transmission structure of the GWG sum and difference network structure through the coupling gap on the second metal plate.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] First, the millimeter-wave single-pulse filter array antenna based on gap waveguide and differential network feeding of the present invention realizes SIW multi-stage cavity by loading metal holes in a dielectric substrate with printed metal layers on the upper and lower surfaces, and realizes filtering performance by coupling between multi-stage cavities. The antenna does not increase the complexity of the overall structure in the process of loading metal vias to realize multi-stage cavity, and produces better filtering performance without increasing the difficulty of processing. At the same time, the use of SIW feeding structure facilitates its integration with the feeding network, which is conducive to the design of larger-scale antenna arrays.

[0026] Second, the millimeter-wave single pulse filter array antenna based on gap waveguide sum difference network feeding of the present invention, the proposed GWG sum difference network generates 0° and 180° phase difference through the waveguide magic T structure, which simply realizes the requirement of single pulse antenna to generate sum difference beam. Energy is transmitted in the air gap of GWG, avoiding the loss of transmission in the dielectric plate, which is conducive to improving antenna efficiency.

[0027] Third, the millimeter-wave single-pulse filter array antenna based on gap waveguide and difference network feeding of the present invention, the proposed GWG and difference network is coupled with the filter antenna array through a slot, and the SIW waveguide structure feeds the antenna unit in the form of series feeding, which can reduce the size of the antenna feeding network and improve its integration; the energy distribution of each antenna unit can be changed more easily by changing the angle of rotation of the slot, thereby reducing the side lobes of the antenna array and improving the detection accuracy.

[0028] Fourth, the millimeter-wave single-pulse filter array antenna based on gap waveguide and difference network feeding of the present invention combines the filter antenna with the single-pulse antenna, and has both the frequency selection performance of the filter antenna and the high-precision characteristics of the single-pulse antenna, and has the advantages of multi-function and high integration. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A three-dimensional schematic diagram of a millimeter-wave single pulse filter array antenna based on gap waveguide and difference network feeding proposed in the present invention;

[0030] Figure 2 A three-dimensional schematic diagram of a SIW filter antenna array composed of a microstrip multilayer board structure loaded with metal vias and surface slots according to the present invention;

[0031] Figure 3 A side view of a SIW filter array antenna composed of a microstrip multilayer board structure loaded with metal vias and surface slots according to the present invention and a schematic diagram of the dimension marking of the laminated structure;

[0032] Figure 4 It is a top view and dimensioning schematic diagram of the metal layer 1 of the SIW filter array antenna;

[0033] Figure 5 It is a top view and dimensioning diagram of metal layers 2 and 3 of the SIW filter array antenna;

[0034] Figure 6 It is a top view and dimensioning schematic diagram of the metal layer 4 of the SIW filter array antenna;

[0035] Figure 7 It is a top view and dimensioning schematic diagram of the metal layer 5 of the SIW filter array antenna;

[0036] Figure 8 It is a top view and dimensioning schematic diagram of the metal through hole 6 of the SIW filter array antenna;

[0037] Fig. 9 It is a top view and dimensioning schematic diagram of the metal through hole 7 of the SIW filter array antenna;

[0038] Fig.10 A three-dimensional schematic diagram of a GWG and difference network structure composed of metal plates with square pins according to the present invention (the T metal plate 13 is hidden for clarity);

[0039] Fig.11 A side view of a GWG sum network structure composed of metal plates with square pins 12 according to the present invention and a schematic diagram of the dimension marking of a GWG unit;

[0040] Fig.12 It is a top view and dimensioning schematic diagram of the GWG and difference network T metal plate 13;

[0041] Fig.13 It is a top view and dimensioning schematic diagram of the GWG and difference network M metal plate 14;

[0042] Fig.14 It is a top view of the GWG and difference network B metal plate 15;

[0043] Fig.15 It is a top view and dimensioning diagram of the upper structure of the GWG and difference network;

[0044] Fig.16 It is a top view and dimensioning diagram of the lower structure of the GWG and difference network;

[0045] Fig.17 This is a schematic diagram of the simulation results of the gain-frequency curve of the single pulse filter array antenna;

[0046] Fig.18 It is a schematic diagram of the simulation results of the horizontal dimension and beam pattern of the single pulse filter array antenna;

[0047] Fig.19It is a schematic diagram of the simulation results of the horizontal difference beam pattern of the single pulse filter array antenna;

[0048] Fig. 20 It is a schematic diagram of the simulation results of the elevation-dimension radiation pattern of the single pulse filter array antenna;

[0049] Fig.21 This is a three-dimensional exploded view of the millimeter-wave single pulse filter array antenna based on gap waveguide and difference network feeding of the present invention. DETAILED DESCRIPTION

[0050] The embodiments of the present invention are further described in detail below with reference to the accompanying drawings.

[0051] The three-dimensional structure of a millimeter wave single pulse filtering antenna based on gap waveguide and differential network feeding designed by the present invention is as follows Figure 1 As shown, the single pulse antenna structure includes two parts, namely, a SIW filter antenna array composed of metal vias and surface slots loaded on a microstrip multilayer board structure and a GWG sum-difference network structure composed of a metal plate with square pins.

[0052] See also Fig.21The SIW filtering antenna array is composed of three dielectric substrates (referred to as T substrate 8, M substrate 9 and B substrate 10, respectively) with metal layers on the upper, middle and lower surfaces, and a layer of prepreg 11. The metal via 6 passes through the T substrate 8, M substrate 9 and prepreg 10, and together with the metal layers 1, 2, 3, 4 on the upper and lower surfaces of the T substrate 8 and the M substrate 9, constitute the latter two resonant cavities of the antenna; the metal via 7 is located in the B substrate 10, and together with the metal layers 4 and 5 on the upper and lower surfaces of the B substrate 10, constitute the feeding path and the first-level cavity of the antenna. The antenna unit of the present invention is composed of three resonant cavities, one horizontal (first-level resonant cavity) and two vertical (second and third-level resonant cavities), which are fed by the SIW transmission structure and the filtering performance is achieved by coupling between the cavities. Specifically, energy is coupled into the cavity through the gap loaded on the metal layer 5 on the lower surface of the B substrate 10, and after being transmitted in the feeding path and the primary cavity composed of the metal layers 4, 5 and metal vias 6 on the upper and lower surfaces of the B substrate 10, it enters the secondary resonant cavity composed of the metal layers 3, 4 and metal holes 6 on the upper and lower surfaces of the M substrate 9 through the coupling gap loaded on the metal layer 4 on the upper surface of the B substrate 10, and then enters the tertiary resonant cavity composed of the metal layers 1, 2 and metal holes 6 on the upper and lower surfaces of the T substrate 8 through the coupling gap loaded on the metal layer 3 on the upper surface of the M substrate 9 and the metal layer 2 on the lower surface of the T substrate 8, and finally radiates into the free space through the gap loaded on the metal layer 1 on the upper surface of the T substrate 8. The operating frequency of the present invention can be designed in the millimeter wave band. The dielectric substrates used are all Rogers 4350B, and their relevant electrical parameters are εr=3.66, tanδ=0.0037, and the thickness of all dielectric substrates is 0.254mm; the semi-cured sheet used is Rogers RO4450F, and its relevant electrical parameters are εr=3.52, tanδ=0.004, and the thickness after pressing is 0.1mm.

[0053] The GWG sum-difference network is composed of three layers of metal plates with square metal pins 12 (referred to as T metal plate 13, M metal plate 14 and B metal plate 15, respectively). The upper and lower layers of metal plates and pins constitute a GWG unit. The periodic arrangement can suppress the propagation of electromagnetic waves at a specific frequency and can be used to construct a waveguide structure. The square pins on the lower surface of the T metal plate 13 and the square pins on the upper surface of the M metal plate 14 constitute the upper layer of the GWG sum-difference network, and the square pins 12 on the lower surface of the M metal plate 14 and the square pins on the upper surface of the B metal plate 15 constitute the lower layer of the GWG sum-difference network. The space between the two layers of metal plates is filled with air. There are two input ports of sum and difference in the lower GWG sum-difference network. After the energy is fed by the sum port or the difference port, it is transmitted in the lower feeding network, enters the upper feeding network through the coupling slot on the M metal plate 14, and then couples into the microstrip antenna array through the slot loaded on the upper surface of the T metal plate 13. The GWG sum-difference network of the present invention can be designed to work in a frequency band that matches the upper antenna array. The gap loaded by the T metal plate 13 corresponds one-to-one to the gap loaded by the metal layer 5, and the size of the gap loaded by the T metal plate 13 is slightly larger than the size of the gap loaded by the metal layer 5. The metal pins 12 are arranged in a certain period, and the electromagnetic waves are transmitted in the waveguide structure surrounded by the pins.

[0054] like Figure 1 As shown, a three-dimensional schematic diagram of a millimeter-wave single pulse filter antenna based on gap waveguide and differential network feeding proposed by the present invention, the single pulse antenna structure includes two parts, namely, a SIW filter antenna array composed of metal vias and surface slits loaded on a microstrip multilayer board structure and a GWG and differential network structure composed of a metal plate with square pins. The overall antenna is 110.2mm long in the y-axis direction and 81.2mm long in the x-axis direction.

[0055] like Figure 2 and Figure 3 As shown, they are respectively a three-dimensional schematic diagram, a side view and dimension annotation of a SIW filtering antenna array composed of metal vias and surface slits loaded on a microstrip multilayer board structure proposed according to the present invention. The filtering antenna array is composed of a dielectric substrate with three layers of metal layers covered on the upper, middle and lower surfaces and a layer of prepreg. Metal holes are loaded in the dielectric substrate and the prepreg to form a resonant cavity of the antenna, and gaps are loaded on the metal layer to achieve coupling between the cavities and radiation of the antenna. Its specific structural parameters are: the thickness of the three layers of dielectric substrates is 0.254mm, the thickness of the prepreg is 0.1mm, and the thickness of the metal layer is 0.5oz.

[0056] like Figure 4The figure shows the top view and dimensioning of metal layer 1 in the SIW filter antenna array. This layer is the antenna radiation layer. The double slits shown in the figure constitute a radiation unit of the antenna. 32 antenna units are arranged in a 2×16 layout to form an antenna array with a spacing of 6mm. The length of each slit in the antenna unit is 2.8mm, the width is 0.35mm, and the double slit spacing is 1.59mm.

[0057] like Figure 5 The figure shows the top view and dimensioning of metal layers 2 and 3 in the SIW filter antenna array. These two layers are coupling slot layers, and electromagnetic energy enters the third resonant cavity from the secondary resonant cavity through the coupling slots. The coupling slots are also arranged in a 2×16 layout, and are located in the center of the two radiation slots in the y-axis direction, with a length of 2.85 mm and a width of 0.25 mm.

[0058] like Figure 6 The figure shows a top view and dimensioning of the metal layer 4 in the SIW filter antenna array. This layer is a coupling slot layer, and electromagnetic energy enters the secondary resonant cavity from the primary resonant cavity through the coupling slot. The coupling slots are arranged in a 2×16 layout, with a spacing of 6 mm in the y-axis direction and 9.58 mm in the x-axis direction, a length of 2.85 mm, and a width of 0.25 mm.

[0059] like Figure 7 As shown, it is a top view and dimensioning of the metal layer 5 in the SIW filter antenna array. This layer is a coupling slot layer, and the electromagnetic energy enters the SIW feeding structure and the first-order resonant cavity at the bottom of the multilayer board from the GWG and difference network through the coupling slot. The coupling slots are arranged in a 2×16 layout, with a spacing of 6mm in the y-axis direction, a center spacing of 24mm in the x-axis direction, a length of 3mm, and a width of 0.25mm. The coupling slots are arranged obliquely, and the direction is 24° counterclockwise or clockwise rotation based on the x-axis direction. The rotation directions of adjacent slots in the y-axis direction are opposite to ensure that the electromagnetic energy input to the antenna unit is in phase, and the rotation directions of adjacent slots in the x-axis direction are the same.

[0060] like Figure 8 As shown in the figure, it is a top view and dimensioning of the arrangement of metal pillars 6 in the dielectric substrate in the SIW filter antenna array. The metal pillars go from metal layer 1 to metal layer 4, pass through metal layers 2, 3, dielectric substrates 8, 9 and prepreg 11, and have a radius r = 0.15 mm. They are periodically arranged to form a square cavity, which serves as the secondary and tertiary resonant cavity of the antenna unit. The square cavities are arranged in a 2×16 layout, and each square cavity has a length of 6 mm in the y-axis direction and a length of 6.28 mm in the x-axis direction.

[0061] like Fig. 9As shown, it is a top view and dimensioning of the arrangement of metal pillars 7 in the dielectric substrate in the SIW filter antenna array. The metal pillars go from metal layer 4 to metal layer 5, pass through the dielectric substrate 10, and have a radius r = 0.15mm. They are periodically arranged to form a square cavity as the feeding structure of the antenna unit. The square cavities are arranged in a 2×16 layout, and each square cavity is 4.35mm long in the y-axis direction and 12.75mm long in the x-axis direction. There are two metal holes with a spacing of 2.1mm in the feeding structure, which divide a cavity with a length of 6.3mm in the x-axis direction in the feeding structure as the primary resonant cavity of the antenna.

[0062] like Fig.10 and Fig.11 The following are the three-dimensional schematic diagram, side view and dimension annotation of a GWG sum-difference network structure composed of metal plates with square pins according to the present invention. The GWG sum-difference network structure consists of three layers of metal plates with square metal pins 12, the upper, middle and lower layers of metal plates and the protruding pins constitute a GWG unit, and its periodic arrangement can suppress the propagation of electromagnetic waves at a specific frequency and can be used to construct a waveguide structure. The space between the two layers of metal plates is filled with air. In order to show it more clearly, Fig.10 The upper metal plate is hidden in the figure. The specific structural parameters are: the metal plate thickness is 0.5mm, the square metal pin height is 1mm, the side length is 1.4mm, the gap between the upper and lower pins is 0.1mm, and the side length of each GWG unit is 2.8mm.

[0063] like Fig.12 As shown, it is a top view and dimensioning of the T metal plate 13 in the GWG and difference network structure. This layer is a coupling slot layer, and electromagnetic energy enters the SIW feeding structure and the first-order resonant cavity at the bottom of the multilayer board from the upper layer of the GWG and difference network through the coupling slot. The coupling slot is arranged in a 2×16 layout, and the center of the slot corresponds to the center of the slot on the metal layer 5, with the same rotation direction and angle, and slightly larger length and width. The slot spacing in the y-axis direction is 6mm, the center spacing in the x-axis direction is 24mm, the length is 3.5mm, and the width is 0.5mm.

[0064] like Fig.13 As shown, it is a top view and dimensioning of the M metal plate 14 in the GWG sum difference network structure. This layer is a coupling gap layer, and electromagnetic energy enters the upper layer of the multi-GWG sum difference network from the lower layer of the GWG sum difference network through the coupling gap. There are two types of coupling gaps, each with two, which are respectively suitable for coupling between the upper and lower layers of the network when energy is input from the sum port and the difference port. The length of the coupling gap of the sum port is 4.3mm and the width is 1.1mm; the length of the coupling gap of the difference port is 4.26mm and the width is 1.1mm.

[0065] like Fig.14 The figure shows a top view of the B metal plate 15 in the GWG and differential network structure. The metal plate is a component of the lower transmission structure in the GWG and differential network, and no loading gap treatment is performed.

[0066] like Fig.15 As shown, it is a top view and dimension annotation of the upper transmission structure in the GWG sum difference network structure. The structure is composed of periodically arranged GWG units and can be divided into two symmetrical upper and lower parts, each of which is composed of a T-shaped power splitter structure and an angle structure. The sum port coupling slot is located at the tail of the angle, and the difference port coupling slot is located in the middle of the T-shaped power splitter. After the energy is coupled into the upper layer by the lower transmission structure, it passes through the T-shaped power splitter and enters the antenna array through the slots on the T metal plate 13 and the metal layer 5.

[0067] like Fig.16 As shown in FIG. 1 , it is a top view and dimension annotation of the lower transmission structure in the GWG sum-difference network structure. The structure is composed of periodically arranged GWG units and can be divided into two parts, left and right. Each part has an input port, where the left side is the sum port and the right side is the difference port. After the energy is input from the sum / difference port, it enters the upper transmission structure of the GWG sum-difference network structure through the coupling gap on the M metal plate 13.

[0068] like Fig.17 As shown in FIG. 1 , the gain curve simulation result of the single pulse filter antenna is shown. It can be observed that the in-band gain of the antenna reaches 20dBi and the out-of-band suppression exceeds -35dB.

[0069] like Fig.18 As shown, it is the simulation result of the horizontal dimension and beam pattern of the single pulse filter antenna at the frequency of 35GHz.

[0070] like Fig.19 As shown, it is the simulation result of the horizontal dimensional difference beam pattern of the single pulse filter antenna at the frequency of 35GHz.

[0071] like Fig. 20 As shown, it is the simulation result of the elevation-dimension radiation pattern of the single pulse filter antenna at the frequency of 35 GHz.

[0072] The present invention is a millimeter wave single pulse filter array antenna based on gap waveguide (GWG) and difference network feeding. The single pulse antenna structure includes two parts, namely, a substrate integrated waveguide (SIW) filter antenna array composed of metal vias loaded in a microstrip multilayer board structure and a metal layer loaded with slots, and a GWG and difference network structure composed of a metal plate with square pins. The present invention realizes a slot filter antenna with a third-order SIW cavity by drilling holes in the antenna dielectric substrate and opening slots on the metal layer. Furthermore, a GWG transmission structure is formed by upper and lower corresponding metal plates with square pins, and a magic T structure is formed by coupling between double-layer GWGs to form a sum and difference feeding network. Finally, the sum and difference network is connected to the slot antenna to form a sum and difference beam, forming a single pulse filter antenna operating in the millimeter wave frequency band. Compared with existing antenna arrays, the present invention combines a filtering antenna with a single-pulse antenna, and has both the frequency selection characteristics of a filtering antenna and the high-precision target positioning characteristics of a single-pulse antenna. It has the advantages of high integration and multi-functions, and can be applied to target detection in the millimeter-wave frequency band.

[0073] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of complete hardware embodiments, complete software embodiments, or embodiments in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code. The scheme in the embodiments of the present application can be implemented in various computer languages, for example, object-oriented programming language Java and literal scripting language JavaScript, etc.

[0074] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0075] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0076] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0077] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0078] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A millimeter wave single pulse filter array antenna based on gap waveguide and difference network feeding, characterized in that: The millimeter wave single pulse filter array antenna includes a SIW filter antenna array composed of metal vias and metal layer slits loaded on a microstrip multilayer board structure and a GWG sum-difference network structure composed of a metal plate with square pins; The GWG sum-difference network structure is composed of three layers of metal plates with square metal pins, the space between two adjacent layers of metal plates is filled with air, the two adjacent layers of metal plates and the protruding pins constitute a GWG unit, and the electromagnetic wave is transmitted in the waveguide structure surrounded by the pins; after the energy is fed from the sum port or the difference port, it passes through the two-layer feeding network and is coupled into the SIW filter antenna array through the slots loaded on the surface of the metal plate; The SIW filter antenna array is composed of three layers of dielectric substrates covered with metal layers and a layer of prepreg. Metal holes are loaded in the dielectric substrate and the prepreg to form a resonant cavity of the antenna, and gaps are loaded on the metal layer to achieve coupling between cavities and radiation of the antenna. The energy is coupled into the cavity through the gaps on the metal layer on the lower surface of the lowest dielectric substrate, and after being transmitted through the resonant cavity, it is radiated into the free space through the gaps on the metal layer on the upper surface of the highest dielectric substrate.

2. The millimeter wave single pulse filter array antenna based on gap waveguide and difference network feeding according to claim 1 is characterized in that: The operating frequencies of the SIW filter antenna array and the GWG sum-difference network structure match each other, and both operate in the millimeter wave frequency band.

3. The millimeter wave single pulse filter array antenna based on gap waveguide and difference network feeding according to claim 1 is characterized in that: The gap loaded by the uppermost metal plate corresponds one to one with the gap loaded by the metal layer below the lowermost dielectric substrate, and the size of the gap loaded by the uppermost metal plate is larger than the size of the gap loaded by the metal layer below the lowermost dielectric substrate.

4. The millimeter wave single pulse filter array antenna based on gap waveguide and difference network feeding according to claim 1, characterized in that: The SIW filter antenna array is formed by stacking a first dielectric substrate, a prepreg, a second dielectric substrate and a third dielectric substrate, wherein the surfaces of the first dielectric substrate, the second dielectric substrate and the third dielectric substrate are covered with a metal layer; a first metal via passes through the first dielectric substrate, the prepreg and the second dielectric substrate, and together with the metal layers on the upper and lower surfaces of the first dielectric substrate and the second substrate, forms a secondary resonant cavity and a tertiary resonant cavity of the antenna; a second metal via is located in the third dielectric substrate, and together with the metal layers on the upper and lower surfaces of the third dielectric substrate, forms a feeding path and a primary resonant cavity of the antenna; Energy is coupled into the cavity through the gap loaded on the metal layer on the lower surface of the third dielectric substrate, and after being transmitted in the feeding path and the primary resonant cavity composed of the third dielectric substrate and the metal layers and metal vias on its upper and lower surfaces, it enters the secondary resonant cavity composed of the second dielectric substrate and the metal layers and metal holes on its upper and lower surfaces through the coupling gap loaded on the metal layer on the upper surface of the third dielectric substrate, and then enters the tertiary resonant cavity composed of the first dielectric substrate and the metal holes on its upper and lower surfaces through the coupling gap loaded on the metal layer on the upper surface of the second dielectric substrate and the metal layer on the lower surface of the first dielectric substrate, and finally radiates into the free space through the gap loaded on the metal layer on the upper surface of the first dielectric substrate.

5. The millimeter wave single pulse filter array antenna based on gap waveguide and difference network feeding according to claim 4 is characterized in that: The SIW filter antenna array is formed by connecting 32 antenna units in series in a 2×16 layout.

6. The millimeter wave single pulse filter array antenna based on gap waveguide and difference network feeding according to claim 5, characterized in that: The metal layer on the upper surface of the first dielectric substrate is an antenna radiation layer, and a plurality of slots are arranged above the first dielectric substrate, and every two slots constitute a radiation unit of the antenna, and 32 radiation units are arranged in a 2×16 layout to form an antenna array; The metal layer on the lower surface of the first dielectric substrate and the metal layer on the upper surface of the second dielectric substrate are first coupling slot layers, and electromagnetic energy enters the third-level resonant cavity from the secondary resonant cavity through the first coupling slots; the first coupling slots are arranged in a 2×16 layout; The metal layer on the lower surface of the second dielectric substrate is a second coupling slot layer, and electromagnetic energy enters the secondary resonant cavity from the primary resonant cavity through the second coupling slots, and the second coupling slots are arranged in a 2×16 layout; The metal layer on the lower surface of the third dielectric substrate is a third coupling slot layer, and electromagnetic energy enters the SIW feeding structure and the primary resonant cavity at the bottom layer of the SIW filtering antenna array from the GWG sum difference network structure through the third coupling slots, and the third coupling slots are arranged in a 2×16 layout; wherein the third coupling slots are arranged obliquely, and the direction is counterclockwise or clockwise rotating at a preset angle based on the x-axis direction, and the rotation directions of adjacent slots in the y-axis direction are opposite, so that the electromagnetic energy input to the antenna unit is in phase, and the rotation directions of adjacent slots in the x-axis direction are the same.

7. The millimeter wave single pulse filter array antenna based on gap waveguide and difference network feeding according to claim 1, characterized in that: The GWG sum-difference network structure comprises a first metal plate with square metal pins, a second metal plate, and a third metal plate stacked together, wherein the square pins on the lower surface of the first metal plate and the square pins on the upper surface of the second metal plate constitute an upper GWG sum-difference network, and the square pins on the lower surface of the second metal plate and the square pins on the upper surface of the third metal plate constitute a lower GWG sum-difference network; the space between the two layers of metal plates is filled with air; there are two input ports of sum and difference in the lower GWG sum-difference network, and after energy is fed into the sum port or the difference port, it passes through two layers of feeding networks and is coupled into the microstrip antenna array through the gap loaded on the upper surface of the first metal plate.

8. The millimeter wave single pulse filter array antenna based on gap waveguide and difference network feeding according to claim 7, characterized in that: The GWG sum network structure includes a middle-upper layer transmission structure and a middle-lower layer transmission structure; The middle and upper transmission structure is divided into two symmetrical upper and lower parts, each of which consists of a T-shaped power splitter structure and an angle structure; the sum port coupling slot is located at the tail of the angle, and the difference port coupling slot is located in the middle of the T-shaped power splitter; after the energy is coupled into the upper layer by the lower transmission structure, it passes through the T-shaped power splitter and enters the antenna array through the slots on the metal layer below the first metal plate and the lowest dielectric substrate; The middle and lower transmission structure is divided into two parts, each of which has an input port, the left side of which is the sum port and the right side is the difference port; after the energy is input from the sum / difference port, it enters the upper transmission structure of the GWG sum and difference network structure through the coupling gap on the second metal plate.

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