A three-dimensional integrated array antenna with gap waveguides on hard and soft surfaces and a design method thereof

Abstract

The present invention discloses a hard-soft surface gap waveguide three-dimensional integrated array antenna and a design method thereof, which relates to the field of microwave antennas and is used to improve the bandwidth and structural strength of high-frequency band antenna arrays. The array antenna of the present invention forms a hard-soft surface gap waveguide structure between the radiation array module and the feed network module, forms a hard-soft surface gap waveguide structure between adjacent radiation conductor plates of the radiation array module, forms a hard-soft surface gap waveguide structure between the dividing surfaces of the layered feed network module, and uses a first power distribution network, a second power distribution network and a radiation unit to complete microwave radiation. The present invention effectively reduces the loss of the array antenna, improves the bandwidth of the array antenna, improves the antenna structure strength, and is conducive to three-dimensional integration.

Description

Technical Field

[0001] The invention relates to the field of microwave antennas, in particular to a hard-soft surface gap waveguide three-dimensional integrated array antenna and a design method for the hard-soft surface gap waveguide three-dimensional integrated array antenna. Background Art

[0002] At present, antennas or antenna arrays working in the millimeter wave band require higher gain and lower loss due to the attenuation of high-frequency electromagnetic waves by the atmosphere. Microstrip patches and substrate integrated waveguides are mature technologies with advantages such as low profile, low cost, and easy processing, and they perform well in the manufacture of low-frequency antennas and antenna arrays. However, antennas and antenna arrays made based on microstrip patches and substrate integrated waveguides have high losses and narrow bandwidths, and cannot meet the needs of broadband antenna arrays in the millimeter wave band.

[0003] In order to meet the requirements, the antenna array needs to adopt traveling wave structures such as hollow rectangular waveguides and ridge waveguides during the design process. However, with the increase of frequency, the size of the antenna and antenna array becomes very small, and the existing mechanical processing technology has a very high cost. The common method is to cut the waveguide and fasten it with screws, but this brings the problem of electromagnetic wave leakage. As a non-contact transmission structure proposed in recent years, the gap waveguide technology has a unique structural characteristic that effectively reduces the difficulty of processing and assembly, while maintaining the low loss characteristics of the waveguide structure. The millimeter wave antenna array made based on the non-contact structure has the following two advantages: First, the electrical performance of the antenna does not rely on direct electrical contact like traditional contact integration. The antenna not only has more stable electrical performance, but also has a higher degree of integration; secondly, the use of non-contact technology effectively suppresses the passive intermodulation interference noise caused by metal-oxide-metal contact. The gap waveguide three-dimensional integrated array antenna based on non-contact integration design has the characteristics of high gain, low loss and wide bandwidth in the high frequency band, and is suitable for microwave, millimeter wave and terahertz frequency band circuits and communications.

[0004] The existing non-contact electromagnetic shielding structures all use a bed of nails structure as a two-dimensional artificial magnetic conductor surface to suppress the transmission of electromagnetic waves. The disadvantage of this type of non-contact electromagnetic shielding structure is that in the field of high-frequency applications, since the width of the bed of nails is equivalent to one-fourth of the working wavelength, the higher the frequency and the shorter the wavelength, the smaller the size of the bed of nails will become, the structural strength is relatively low, and there is a risk of breakage.

[0005] Through the above analysis, the problems and defects of the prior art are as follows:

[0006] (1) In the field of high-frequency applications, antennas and antenna arrays made based on microstrip patches and substrate-integrated waveguides have large losses and narrow bandwidths, and cannot meet the needs of broadband antenna arrays in the millimeter-wave frequency band.

[0007] (2) In high-frequency applications, the size of the traditional non-contact nail bed will become very small, the structural strength is relatively low, and there is a risk of breakage.

[0008] (3) As the size of antenna arrays increases, the feeding network becomes extremely complex, usually with a three-dimensional complex structure. The traditional screw fastening solution has the problem of insufficient fastening force and unstable electrical performance under temperature shock due to interference between the fastening structure and the electrical structure. The integration using welding technology faces the problems of high cost and difficulty in later maintenance. Summary of the invention

[0009] The object of the present invention is to provide a hard-soft surface gap waveguide three-dimensional integrated array antenna and a design method thereof to improve the bandwidth and structural strength of the high-frequency band antenna array in order to address all or part of the above-mentioned problems.

[0010] The technical solution adopted by the present invention is as follows:

[0011] A hard-soft surface gap waveguide three-dimensional integrated array antenna, comprising a radiation array module and a feeding network module, wherein a hard-soft surface gap waveguide structure is formed between the bottom of the radiation array module and the top of the feeding network module;

[0012] The feed network module is provided with an input port, which is connected to each output port on the top of the feed network module through a first power distribution network inside the feed network module;

[0013] The radiation array module comprises a first edge radiation electric conductor plate, a second edge radiation electric conductor plate, and at least one internal radiation electric conductor plate sandwiched between the two edge radiation electric conductor plates; a hard-soft surface gap waveguide structure is formed between adjacent radiation electric conductor plates; adjacent radiation electric conductor plates are butt-jointed to form at least one group of radiation units; each group of radiation units is respectively connected to the output port on the top of the feed network module.

[0014] Furthermore, adjacent radiating electric conductor plates are connected to form a second power distribution network, the input ports of the second power distribution network are connected one by one with the output ports on the top of the feeding network module, each output port of the second power distribution network is connected one by one with a radiating unit respectively, and a second power distribution network connects a group of radiating units.

[0015] Furthermore, an impedance converter is connected to the input port of the second power distribution network.

[0016] Furthermore, the second power distribution network adopts a ridge-type power divider structure.

[0017] Furthermore, the feed network module includes at least two layers of feed network structures; a hard-soft surface gap waveguide is formed between adjacent feed network structures.

[0018] Furthermore, all or part of the structure of a first-level power distributor is designed in each layer of the feeding network structure, and after adjacent feeding network structures are connected, the power distributors of each level are cascaded to form the first power distribution network.

[0019] Furthermore, each level of power divider in the first power distribution network is a two-power divider.

[0020] Furthermore, the number of layers of the feed network structure is the same as the number of levels of power distributors included in the first power distribution network, and each subsequent layer of feed network structure is connected to the previous layer of feed network structure to form at least one complete power distributor.

[0021] The present invention also provides a design method for the above-mentioned hard-soft surface gap waveguide three-dimensional integrated array antenna, which includes:

[0022] S1. Establish a minimum lattice three-dimensional model of a hard-soft surface non-contact artificial electromagnetic bandgap material and initialize the size; optimize the size of the artificial electromagnetic bandgap material until it covers the required electromagnetic bandgap;

[0023] S2. Establish an electromagnetic simulation model of the radiation unit and optimize the parameters until the required performance is achieved;

[0024] S3. Establish an electromagnetic simulation model of a complete radiation array module and optimize parameters and dimensions until the required performance is achieved;

[0025] S4, establishing an electromagnetic simulation model of the first power distribution network, and optimizing parameters until the required performance is achieved;

[0026] S5. Combine the radiation array module and the feeding network module to establish a complete hard-soft surface gap waveguide three-dimensional integrated array antenna model, and optimize the overall parameters and dimensions until the required technical indicators are achieved.

[0027] Further, the step S4 includes:

[0028] S41, respectively establish full-wave electromagnetic simulation models of power distributors at various levels of the first power distribution network, and respectively optimize parameters until the required performance is achieved; cascade the power distributors at various levels to establish an electromagnetic simulation model of the feeding network module;

[0029] S42, hierarchically processing the feed network module into at least two layers of feed network structures, and adding a hard-soft standard gap waveguide structure between adjacent layers of feed network structures;

[0030] S43, optimizing parameters of the feed network module until the required performance is achieved.

[0031] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0032] The present invention improves the problems of high loss and narrow frequency band of existing high-frequency band antenna arrays, and adopts transmission lines with traveling wave structures such as hollow rectangular waveguides and double-ridge waveguides, which effectively reduces the loss of array antennas and improves the bandwidth of array antennas. On the other hand, the present invention breaks the traditional electromagnetic shielding structure design concept of gap waveguide array antennas based on a bed of nails, and improves the structural strength of the antenna. Therefore, under the same structural strength requirements, the antenna of the present invention can have a smaller size and a higher operating frequency band. In addition, the metal ridge structure used in the hard and soft surface non-contact artificial electromagnetic bandgap material of the present invention can take into account the integration needs in both horizontal and vertical directions, which is more conducive to three-dimensional integration. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The present invention will now be described by way of example with reference to the accompanying drawings, in which:

[0034] Figure 1 It is a structural diagram of a hard-soft surface gap waveguide three-dimensional integrated array antenna provided in an embodiment of the present invention; wherein (a) is an overall exploded view, (b) is a double-sided structural diagram of an internal radiating electric conductor plate, (c) is an overall structural diagram, (d) is a bottom view of the radiating array module, and (e) is a structural diagram of a first power distribution network.

[0035] Figure 2 It is a schematic diagram of key size parameters of the hard-soft surface gap waveguide three-dimensional integrated array antenna radiation unit provided by an embodiment of the present invention.

[0036] Figure 3 A schematic diagram of key dimension parameters of a radiation array module of a hard-soft surface gap waveguide three-dimensional integrated array antenna provided in an embodiment of the present invention.

[0037] Figure 4 A schematic diagram of the layered structure of a feeding network module of a hard-soft surface gap waveguide three-dimensional integrated array antenna provided in an embodiment of the present invention.

[0038] Figure 5 A flow chart of a design method for a hard-soft surface gap waveguide three-dimensional integrated array antenna provided in an embodiment of the present invention.

[0039] Figure 6 This is a diagram of the dispersion characteristics simulation results of the antenna simulation in an embodiment of the present invention.

[0040] Figure 7 The following are the radiation direction simulation result diagrams of the radiation unit in the embodiment of the present invention; (a) is the E-plane radiation diagram, and (b) is the H-plane radiation diagram.

[0041] Figure 8 This is a diagram of the return loss simulation results of the radiation unit simulation in an embodiment of the present invention.

[0042] Fig. 9 1×8 array return loss simulation result diagram in the embodiment of the present invention.

[0043] Fig.10 This is a diagram of the return loss simulation results of the hard-soft surface gap waveguide three-dimensional integrated array antenna in an embodiment of the present invention.

[0044] Fig.11 This is a graph showing the measured results of the return loss of the hard-soft surface gap waveguide three-dimensional integrated array antenna in an embodiment of the present invention.

[0045] Fig.12 This is a diagram showing the radiation direction simulation results of the hard-soft surface gap waveguide three-dimensional integrated array antenna in an embodiment of the present invention.

[0046] Fig.13 This is a diagram showing the measured results of the radiation direction of the hard-soft surface gap waveguide three-dimensional integrated array antenna in an embodiment of the present invention.

[0047] In the figure, 1, radiation array module; 2, feeding network module; 11, first edge radiation electric conductor plate; 12, internal radiation electric conductor plate; 13, second edge radiation electric conductor plate; 21, first feeding network structure; 22, second feeding network structure; 23, third feeding network structure; 24, fourth feeding network structure; 101, hard surface; 102, soft surface; 103, impedance transformer; 104, first power divider; 105, second power divider; 106, radiation unit; 211, third power divider; 221, fourth power divider; 231, fifth power divider; 241, sixth power divider. DETAILED DESCRIPTION

[0048] All features disclosed in this specification, or steps in all methods or processes disclosed, except mutually exclusive features and / or steps, can be combined in any manner.

[0049] Any feature disclosed in this specification (including any additional claims and abstract), unless otherwise stated, may be replaced by other alternative features that are equivalent or have similar purposes. That is, unless otherwise stated, each feature is only an example of a series of equivalent or similar features.

[0050] In view of the problems that existing antennas made based on microstrip patches and substrate integrated waveguides have large losses and narrow bandwidth, and antennas using traditional non-contact artificial electromagnetic bandgap material structures have low structural strength in high-frequency band scenarios, the embodiments of the present application propose a hard-soft surface gap waveguide three-dimensional integrated array antenna and a design method thereof, aiming to provide a waveguide array antenna with low loss, wide bandwidth and high structural strength in high-frequency band scenarios.

[0051] like Figure 1~Figure 4 As shown, in some embodiments, the hard-soft surface gap waveguide three-dimensional integrated array antenna includes two parts: a radiation array module 1 and a feeding network module 2, and a hard-soft surface gap waveguide structure is formed between the bottom of the radiation array module 1 and the top of the feeding network module 2.

[0052] The hard-soft surface gap waveguide structure is a waveguide structure formed by the docking (non-contact) of the hard surface 101 and the soft surface 102. The main structures of the hard surface 101 and the soft surface 102 are strip metal ridges, but the length directions of the metal ridges on the hard surface 101 and the soft surface 102 are perpendicular to each other. There is a gap between the metal ridges of the hard surface 101 and the soft surface 102, forming a non-contact artificial electromagnetic bandgap material. Non-contact integration has many advantages: first, the electrical performance of the antenna does not rely on direct electrical contact like traditional contact integration. The antenna not only has more stable electrical performance, but also has a higher degree of integration; secondly, the use of non-contact technology effectively suppresses the passive intermodulation interference noise caused by metal-oxide-metal contact. The structural strength of the metal ridges on the hard and soft surfaces is much higher than that of the bed of nails structure, so the structural strength of the antenna can be greatly improved while reducing the antenna loss.

[0053] The feed network module 2 is provided with an input port, which is connected to each output port on the top of the feed network module 2 through the first power distribution network inside the feed network module 2. The first power distribution network distributes the power of the microwave signal input from the input port and transmits it to each output port.

[0054] The radiation array module 1 includes a first edge radiation electric conductor plate 11, a second edge radiation electric conductor plate 13, and at least one internal radiation electric conductor plate 12 sandwiched between the two edge radiation electric conductor plates. A hard-soft surface gap waveguide structure is formed between adjacent radiation electric conductor plates. In addition, adjacent radiation electric conductor plates are butt-jointed to form at least one group of radiation units 106. Each group of radiation units 106 is respectively connected to the output port at the top of the feed network module 2.

[0055] The inner radiation electric conductor plate 12 is a double-sided structure, with a hard surface 101 on one side and a soft surface 102 on the other side. The first edge radiation electric conductor plate 11 and the second edge radiation electric conductor plate 13 have a hard surface 101 on one inner surface and a soft surface 102 on the other inner surface. When combined, the hard surface 101 and the soft surface 102 are opposite to each other, forming a hard-soft surface gap waveguide structure.

[0056] The number of the internal radiation electric conductor plates 12 and the number of the groups of radiation elements 106 formed between every two adjacent radiation electric conductor plates correspond to the number of the output ports on the top of the feed network module 2 .

[0057] In some embodiments, adjacent radiating electric conductor plates are connected to form a second power distribution network, the input port of the second power distribution network is connected one by one with the output port on the top of the feed network module 2, and each output port of the second power distribution network is connected one by one with a radiating unit 106. One second power distribution network is connected to a group of radiating units 106.

[0058] The second power distribution network includes at least one power divider, which is used to distribute the power of the microwave signal transmitted from the top output port of the feed network module 2 and transmit it to the radiation units 106 connected to each output port. The number of output ports of the second power distribution network determines the number of radiation units 106 formed between adjacent radiation conductor plates. As a feasible implementation, the second power distribution network includes two cascaded power dividers, which are referred to as the first power divider 104 and the second power divider 105 in the embodiment of the present application. Each output port of the first power divider 104 is respectively connected to an input port of the second power divider 105, and each output port of the second power divider 105 is respectively connected to a radiation unit 106.

[0059] Assuming that the first power divider 104 and the second power divider 105 are both two-power dividers, each second power distribution network between adjacent radiating electric conductor plates is connected to four radiating elements 106. Assuming that two groups of radiating elements 106 are formed between adjacent radiating electric conductor plates, that is, two second power distribution networks are included, eight radiating elements 106 are formed between adjacent radiating electric conductor plates. Similarly, if the number of stages of the power divider in the second power distribution network changes, or the number of output ports of each stage of the power divider changes, the number of radiating elements 106 formed between adjacent radiating electric conductor plates also changes accordingly.

[0060] In some embodiments, the second power distribution network adopts a ridge-type power divider structure. Taking the two-stage power divider cascade design adopted in the above embodiment as an example, that is, the first power divider 104 and the second power divider 105 are both ridge-type power dividers. Of course, for the same design purpose, it can also be designed as other types of power dividers.

[0061] In some embodiments, the radiation unit 106 is designed as a ridge-type horn radiator. The ridge-type horn radiators are symmetrically designed on adjacent radiation conductor plates.

[0062] Considering that the transmission lines used by the second power distribution network and the feed network module 2 may be different, in some embodiments, an impedance converter 103 is connected to the input port of the second power distribution network for impedance matching. As a feasible implementation, the impedance matcher may be a step impedance converter 103 or an impedance converter 103 of other structures.

[0063] In order to facilitate machining, in some embodiments, the feed network module 2 is designed to include at least two layers of feed network structures for easy layered processing. In order to prevent the problem of electromagnetic wave leakage caused by direct screw fastening between feed network structures, a hard-soft surface gap waveguide is formed between adjacent feed network structures, that is, on the butt joint surfaces of adjacent feed network structures, one is provided with a hard surface 101 and the other is provided with a soft surface 102.

[0064] The purpose of designing the feed network module 2 in layers is mainly to facilitate the processing of the internal first power distribution network. In some embodiments, each layer of the feed network structure is designed with all or part of the structure of a first-level power distributor, and after adjacent feed network structures are connected, the power distributors of each level are cascaded to form the first power distribution network.

[0065] As a preferred embodiment, the number of layers of the designed feeding network structure is the same as the number of levels of power distributors included in the first power distribution network, and each subsequent layer of feeding network structure is connected to the previous layer of feeding network structure to form at least one complete power distributor.

[0066] For example, it is assumed that the first power distributor 104 includes four-stage cascaded power distributors, which are sequentially referred to as the third power distributor 241, the fourth power distributor 231, the fifth power distributor 221 and the sixth power distributor 211 in the embodiment of the present application. Figure 1In the figure, P1 represents the input port of the fifth power divider 221. Correspondingly, the feed network module 2 is divided into 4 layers of feed network structure by planes C1, C2 and C3, which are respectively referred to as the first feed network structure 24, the second feed network structure 23, the third feed network structure 22 and the fourth feed network structure 21 in the embodiment of the present application. When the number of levels of the power dividers included in the first power distribution network changes, the number of layers divided by the feed network module 2 also changes accordingly. Moreover, the number of layers divided by the feed network module 2 may not correspond to the number of levels of the power dividers included in the first power distribution network.

[0067] The input port of the first power distribution network is arranged on the bottom surface of the first feed network structure 24; a part of the third power divider 241 and a part of the fourth power divider 231 are arranged on the top surface of the first feed network structure 24, and the input port of the third power divider 241 is connected to the input port of the first power distribution network. The remaining part of the third power divider 241, the remaining part of the fourth power divider 231, and the connecting passage between the fourth power divider 231 and the third power divider 241 are arranged on the bottom surface of the second feed network structure 23; a part of the fifth power divider 221 is arranged on its top surface. The remaining part of the fifth power divider 221 and the connecting passage between the sixth power divider 211 and the fifth power divider 221 are arranged on the bottom surface of the third feed network structure 22; a part of the sixth power divider 211 is arranged on its top surface. The remaining part of the sixth power divider 211 is arranged on the bottom surface of the fourth feed network structure 21; the output port of the first power divider 104 is arranged on its top surface, and the output port of the sixth power divider 211 is connected one by one with the output port of the first power divider 104. After the first feeding network structure 24 and the second feeding network structure 23 are connected, a complete third power distributor 241 and a fourth power distributor 231 are formed; similarly, after the second feeding network structure 23 and the third feeding network structure 22 are connected, an overall fifth power distributor 221 is formed; after the third feeding network structure 22 and the fourth feeding network structure 21 are connected, an overall sixth power distributor 211 is formed.

[0068] In some embodiments, each level of power divider in the first power distribution network is a two-power divider. Taking the above embodiment in which the first power distribution network includes a 4-level power divider as an example, the feed network module 2 includes 16 output ports, and the corresponding radiation array module 1 is designed with 16 groups of radiation units 106. And since there is a symmetrical power distribution sub-network starting from the fourth-level power divider, the power distribution sub-network formed by the fourth-level power divider to the sixth-level power divider can be designed as a bilateral symmetrical structure, so that only two groups of radiation units 106 can be designed between adjacent radiation conductor plates, and each group corresponds to a single-sided power distribution sub-network.

[0069] The embodiment of the present application also proposes a design method for a hard-soft surface gap waveguide three-dimensional integrated array antenna. The hard-soft surface gap waveguide three-dimensional integrated array antenna here is the hard-soft surface gap waveguide three-dimensional integrated array antenna in the above embodiment.

[0070] Before introducing the antenna design method, the definition of relevant parameters in the hard-soft surface gap waveguide three-dimensional integrated array antenna is introduced. The width of the top of the hard surface 101 on the radiating conductor plate is w t1 , the bottom width is w b1 , the depth is d 1 , Hard Surface 101 cycle is p 1 ; The width of the top of the soft surface 102 on the radiating electric conductor plate is w t2 , the bottom width is w b2 , the depth is d 2 , the groove period is p 2 ; The gap between the radiating electric conductor plates is h a ; The width of the radiation element 106 on the radiation conductor plate is w s ; The width of the waveguide slot is w , the metal ridge height is h r , the width is w r , the spacing between the metal ridges is h d ; The width of the metal ridge groove is w g , the length is l g ; Metal adapter width is w u , the length is l u .

[0071] like Figure 5 As shown, in some embodiments, the antenna design method includes:

[0072] S1. Establish a minimum lattice three-dimensional model of non-contact artificial electromagnetic bandgap materials on hard and soft surfaces and initialize the size; optimize the size of the artificial electromagnetic bandgap material until it covers the required electromagnetic bandgap.

[0073] For the initialization process, in some feasible implementations, if the center frequency of the desired (i.e., target) electromagnetic bandgap is f0 ,but w t1 , w b1 , d 1 , w t2 , w b2 , d 2 The initial values ​​are set to , p 1 , p 2 The initial values ​​are set to ,in c is the speed of light, h a The initial value is set to .

[0074] In the process of optimizing the size of the artificial electromagnetic bandgap material, in some feasible implementations, if the center frequency of the electromagnetic bandgap of the model is lower than the center frequency of the target electromagnetic bandgap, the w t1 , w b1 , d 1 , w t2 , w b2 , d 2 If the percentage bandwidth of the electromagnetic bandgap of the model is smaller than the percentage bandwidth of the target electromagnetic bandgap, then decrease h a , otherwise maintain h a No change or appropriate increase.

[0075] S2. Establish an electromagnetic simulation model of the radiation unit 106 and optimize the parameters until the required performance is achieved.

[0076] In some feasible implementations, the maximum allowable size of the radiation unit 106 is determined according to technical indicators such as the antenna operating frequency, area restriction conditions, and total gain requirements, and under the size restriction, the maximum allowable size of the radiation unit 106 is adjusted. h r , h d , w s One or more of the above can enable the radiation unit 106 to obtain the required gain, beam width and the lowest possible return loss.

[0077] S3. Establish an electromagnetic simulation model of the complete radiation array module 1, and optimize the parameters and dimensions until the required performance is achieved.

[0078] In an embodiment in which the radiation array module 1 is designed with a second power distribution network, such as the embodiment in the foregoing embodiment including the first power distributor 104 and the second power distributor 105, an electromagnetic simulation model of the first power distributor 104 and the second power distributor 105 is established and power and phase distribution design is performed.

[0079] In the embodiment where the second power distribution network is connected to the impedance transformer 103, an electromagnetic simulation model of the impedance transformer 103 is also established and a broadband and low-echo optimization design is performed.

[0080] Based on the specific implementation of the radiation array module 1, the radiation unit 106, the second power divider 105, the first power divider 104 and the impedance transformer 103 are cascaded to establish an electromagnetic simulation model of the complete radiation array module 1. On this basis, performance and size optimization are performed. Specific adjustment parameters include the width of the waveguide slots on each radiation conductor board. w , the metal ridge width is w r , Metal ridge groove width w g , Groove length l g , Metal Dispenser Width w u and length l u .

[0081] S4. Establish an electromagnetic simulation model of the first power distribution network and optimize parameters until the required performance is achieved.

[0082] The first power distribution network has different optimization modes according to different structures of the feed network module 2. In the embodiment where the feed network module 2 is designed in layers, this step S4 includes the following sub-steps:

[0083] S41, respectively establish full-wave electromagnetic simulation models of power distributors at each stage of the first power distribution network, and respectively optimize parameters until the required performance is achieved; cascade the power distributors at each stage to establish an electromagnetic simulation model of the feeding network module 2.

[0084] Taking the first power distribution network including 4-level power dividers as an example, full-wave electromagnetic simulation models of the third power divider 241, the fourth power divider 231, the fifth power divider 221 and the sixth power divider 211 are established, and the parameters are optimized to obtain the required power and phase distribution ratios. Then, the 4-level power dividers are cascaded to perform the overall design of the electromagnetic simulation model of the feed network module 2.

[0085] S42, layering the feed network module 2 into at least two layers of feed network structures, and adding a hard-soft standard gap waveguide structure between adjacent layers of feed network structures.

[0086] Taking the embodiment in sub-step S41 as an example, in sub-step S42, according to the characteristics of processing technologies such as CNC machining and 3D printing, the feed network module 2 is divided into a 4-layer feed network structure, and a hard surface 101 and a soft surface 102 are added between each two adjacent layers of the feed network structure for electromagnetic shielding.

[0087] S43, optimizing parameters of the feeding network module 2 until the required performance is achieved.

[0088] Fine-tune the structural parameters of the feed network to obtain the lowest return loss, and correct the power and phase distribution.

[0089] S5. Combine the radiation array module 1 and the feeding network module 2 to establish a complete hard-soft surface gap waveguide three-dimensional integrated array antenna model, and optimize the overall parameters and dimensions until the required technical indicators are achieved.

[0090] The following takes an array antenna with a planar electromagnetic shielding structure and a frequency band covering 33 GHz-57 GHz as an example to illustrate the specific implementation process of the antenna design method in this embodiment.

[0091] S1. Establish the minimum lattice three-dimensional electromagnetic model of the hard and soft surface non-contact artificial electromagnetic band line material and set the initial size. The initial value of the electromagnetic bandgap size parameter is: the center frequency of the electromagnetic bandgap is 45GHz, w t1 , w b1 , d 1 , w t2 , w b2 , d 2 The initial values ​​of the parameters are set to 1.5 mm. p 1 , p 2 The initial value is set to 3mm. h a The initial value of is set to 0.05mm. Compare the simulated electromagnetic bandgap range with the target electromagnetic bandgap range, and use full-wave electromagnetic field simulation software to optimize the size of the hard and soft surface electromagnetic bandgap materials until the required electromagnetic bandgap is covered. w t1 , w t2Change to 1.6mm, w b1 , w b2 Change to 1.3mm, d 1 , d 2 Change to 1.2mm, and h a The new electromagnetic bandgap range is 30.2GHz-74.8GHz, covering the range of 33GHz-57GHz. The simulation dispersion diagram results are as follows: Figure 6 shown.

[0092] S2. Establish an electromagnetic simulation model of the radiation unit 106 and determine the initial values ​​of the size parameters of the radiation unit 106: h r The initial value is set to 1.1 mm. h d The initial value is set to 0.2 mm. w s The initial value of is set to 1.2 mm. The maximum allowable size of the radiation unit 106 is determined based on the antenna operating frequency, area restriction conditions, total gain requirements and other technical indicators, and the size of the hard and soft surface electromagnetic bandgap materials is optimized using full-wave electromagnetic field simulation software. The return loss and radiation pattern of the radiation unit 106 are obtained as shown in Figure 7 , Figure 8 shown.

[0093] S3, establish the electromagnetic simulation model of the first power divider 104 and the second power divider 105 and perform power and phase distribution design, establish the electromagnetic simulation model of the impedance converter 103 and perform broadband and low echo optimization design, and then cascade the radiation unit 106, the second power divider 105, the first power divider 104 and the impedance converter 103. Establish the complete electromagnetic simulation model of the radiation array module 1 and determine the initial value of the radiation array module 1 parameters: w The initial value is set to 5.0 mm. w r The initial value is set to 1 mm. w g , l g The initial value is set to 1.2 mm. w u , l u The initial value of is set to 1.5 mm. The size optimization is performed using full-wave electromagnetic field simulation software. It should be noted that there is coupling between the radiation units 106, which will affect the overall array. Therefore, the parameters in step S2 still need to be optimized. The final result after optimization is:h r 1mm, h d 0.4mm, d 1 , w s 1mm, w 5mm, l g 2.52mm, w g remain unchanged, w u , l After optimization and adjustment, the return loss and radiation pattern of the radiation unit 106 are as follows: Figure 7 , Figure 8 As shown, the return loss of the radiation array module 1 is Fig. 9 shown.

[0094] S4. Establish full-wave electromagnetic simulation models of the third power divider 241, the fourth power divider 231, the fifth power divider 221 and the sixth power divider 211, optimize parameters after establishing basic dimensions, obtain the required power and phase distribution ratios, and then cascade them for overall optimization design of the feeding module.

[0095] S5. According to the characteristics of CNC machining, 3D printing and other processing technologies, the feed network module 2 is layered, and a hard surface 101 and a soft surface 102 are added on both sides of the interface for electromagnetic shielding. Then, the feed network structure parameters are fine-tuned to obtain the lowest return loss, and the power and phase distribution are corrected.

[0096] S6. Establish a complete array antenna model and perform overall optimization until all technical indicators reach the design goals.

[0097] like Fig.10 , Fig.12 The figure shows the simulation results and measured results of the return loss of the designed array antenna. Fig.11 , Fig.13 The figure shows the simulation result and the measured result of the radiation direction of the designed array antenna. The results show that the array antenna provided by the present application has excellent performances such as low loss and high bandwidth.

[0098] The present invention is not limited to the above-mentioned specific embodiments, but extends to any new features or any new combination disclosed in this specification, as well as any new method or process steps or any new combination disclosed.

Claims

1. A hard-soft surface gap waveguide three-dimensional integrated array antenna, characterized in that: The invention comprises a radiation array module (1) and a feeding network module (2), wherein a hard-soft surface gap waveguide structure is formed between the bottom of the radiation array module (1) and the top of the feeding network module (2); the hard-soft surface gap waveguide structure is a waveguide structure formed by non-contact docking of a hard surface (101) and a soft surface (102), wherein both the hard surface (101) and the soft surface (102) comprise strip-shaped metal ridges, and the length directions of the strip-shaped metal ridges on the hard surface (101) and the soft surface (102) are perpendicular to each other; The feed network module (2) is provided with an input port, and the input port is respectively connected to each output port on the top of the feed network module (2) via a first power distribution network inside the feed network module (2); the feed network module (2) comprises at least two layers of feed network structures; a hard-soft surface gap waveguide is formed between adjacent feed network structures, that is, on the butt joint surfaces of adjacent feed network structures, one is provided with a hard surface (101) and the other is provided with a soft surface (102); The radiation array module (1) comprises a first edge radiation electric conductor plate (11), a second edge radiation electric conductor plate (13), and at least one internal radiation electric conductor plate (12) sandwiched between the two edge radiation electric conductor plates; a hard-soft surface gap waveguide structure is formed between adjacent radiation electric conductor plates, wherein the internal radiation electric conductor plate (12) is a double-sided structure, one side of which is provided with a hard surface (101) and the other side of which is provided with a soft surface (102); the first edge radiation electric conductor plate (11) and the second edge radiation electric conductor plate (13), one of which has an inner surface provided with a hard surface (101), and the other of which has an inner surface provided with a soft surface (102); When combined, the hard surface (101) and the soft surface (102) are opposite to each other, forming a hard-soft surface gap waveguide structure; adjacent radiating electric conductor plates are butted against each other to form at least one group of radiating units (106); each group of radiating units (106) is respectively connected to an output port at the top of the feed network module (2); adjacent radiating electric conductor plates are butted against each other to form a second power distribution network, the input port of the second power distribution network is connected one-to-one with the output port at the top of the feed network module (2), each output port of the second power distribution network is respectively connected one-to-one with a radiating unit (106), and one second power distribution network is connected to a group of radiating units (106).

2. The hard-soft surface gap waveguide three-dimensional integrated array antenna according to claim 1, characterized in that: An impedance converter (103) is connected to the input port of the second power distribution network.

3. The hard-soft surface gap waveguide three-dimensional integrated array antenna according to claim 1, characterized in that: The second power distribution network adopts a ridge-type power divider structure.

4. The hard-soft surface gap waveguide three-dimensional integrated array antenna according to claim 1, characterized in that: All or part of the structure of a first-level power distributor is designed in each layer of the feeding network structure. After adjacent feeding network structures are connected, the power distributors of each level are cascaded to form the first power distribution network.

5. The hard-soft surface gap waveguide three-dimensional integrated array antenna according to claim 4, characterized in that: Each level of power divider in the first power distribution network is a two-power divider.

6. The hard-soft surface gap waveguide three-dimensional integrated array antenna according to claim 4, characterized in that: The number of layers of the feed network structure is the same as the number of levels of power distributors included in the first power distribution network, and each subsequent layer of feed network structure is connected to the previous layer of feed network structure to form at least one complete power distributor.

7. The design method of the hard-soft surface gap waveguide three-dimensional integrated array antenna according to any one of claims 1 to 6, characterized in that: include: S1. Establish a minimum lattice three-dimensional model of a hard-soft surface non-contact artificial electromagnetic bandgap material and initialize the size; optimize the size of the artificial electromagnetic bandgap material until it covers the required electromagnetic bandgap; S2, establishing an electromagnetic simulation model of the radiation unit (106), and optimizing parameters until the required performance is achieved; S3, establishing an electromagnetic simulation model of a complete radiation array module (1), and optimizing parameters and dimensions until the desired performance is achieved; S4, establishing an electromagnetic simulation model of the first power distribution network, and optimizing parameters until the required performance is achieved; S5. Combine the radiation array module (1) and the feeding network module (2) to establish a complete hard-soft surface gap waveguide three-dimensional integrated array antenna model, and optimize the overall parameters and dimensions until the required technical indicators are achieved.

8. The design method of the hard-soft surface gap waveguide three-dimensional integrated array antenna according to claim 7, characterized in that: The step S4 comprises: S41, respectively establishing full-wave electromagnetic simulation models of power distributors at various levels of the first power distribution network, and respectively optimizing parameters until the required performance is achieved; cascading the power distributors at various levels to establish an electromagnetic simulation model of the feed network module (2); S42, hierarchically processing the feed network module (2) into at least two layers of feed network structures, and adding a hard-soft standard gap waveguide structure between adjacent layers of feed network structures; S43, optimizing the parameters of the feeding network module (2) until the required performance is achieved.

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