Millimeter wave waveguide anti-leakage interface device

Abstract

The utility model discloses a millimeter wave waveguide anti-leakage interface device. The device comprises a first rectangular waveguide and a PCB substrate. A first waveguide penetrating through the PCB substrate is arranged on the first side of the PCB substrate, and the center of a first waveguide port of the first rectangular waveguide is aligned with the center of a second waveguide port, located on the first side of the PCB substrate, of the first waveguide; a periodic structure is arranged on the layer where the first side of the PCB substrate is located and surrounds a second waveguide port, and when electromagnetic waves are propagated from the first rectangular waveguide to a first waveguide arranged on the PCB substrate through the first waveguide port, the periodic structure forms an ideal magnetic wall PMC on the corresponding surface and surrounds the waveguide port, so that the electromagnetic waves are transmitted to the first waveguide through the first waveguide port. Therefore, electromagnetic waves are prevented from leaking out from gaps between the first waveguide ports, stable transmission of the electromagnetic waves between the first rectangular waveguide and the first waveguide is ensured, the complexity and production difficulty of a waveguide antenna part mold are effectively reduced, and the production cost is reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to millimeter wave radar technical field especially relates to a millimeter wave waveguide anti-leakage interface device. BACKGROUND

[0002] With the rapid development of ADAS technology, in its function and performance more and more powerful, the performance requirement of the sensor used is also more and more high, millimeter wave radar as the very important sensor in ADAS system, its performance inevitably also put forward new higher requirement, microstrip line because its low cost, simple processing, easy integration and other advantages are widely used in millimeter wave radar, but the loss of microstrip line is larger, and the bandwidth is narrow, which seriously affects the detection performance of millimeter wave radar, therefore, using the waveguide antenna with low loss, large bandwidth to replace the original microstrip antenna naturally also becomes the important direction of 77GHz millimeter wave radar performance breakthrough. Current more and more radar radio frequency chip adopts LIP packaging technology, the original conventional radio frequency transceiver BGA pin on the radio frequency chip is changed into waveguide port, after the radio frequency chip is pasted on the PCB, only the corresponding waveguide port is left on the other side of the PCB for connecting with the waveguide antenna, but because the waveguide antenna and the PCB are two completely different production processes, when the waveguide ports of the two production processes are connected, the waveguide interface between the waveguide antenna and the PCB usually exists gap due to the production process, which causes signal leakage and seriously affects the transmission quality of millimeter wave signal.

[0003] Therefore, how to ensure the stable transmission of millimeter wave in the presence of gap becomes an important problem to be solved in the application of waveguide antenna in millimeter wave radar. UTILITY MODEL CONTENTS

[0004] The utility model discloses a kind of millimeter wave waveguide anti-leakage interface devices, when electromagnetic wave is from first rectangular waveguide through first waveguide port to the first waveguide transmission of being set on PCB substrate, periodic structure forms a ideal magnetic wall PMC on corresponding surface, surrounds around first waveguide port and second waveguide port, to prevent electromagnetic wave from the gap between first waveguide port and second waveguide port leaks, ensure that electromagnetic wave is stably transmitted between first rectangular waveguide and first waveguide, and periodic structure is designed using PCB process, simple structure, mature technology, and it is easy to integrate, also effectively reduce the complexity and production difficulty of waveguide antenna part mold, to reduce production cost.

[0005] To solve the above technical problems, the technical scheme adopted by the utility model is as follows:

[0006] A kind of millimeter wave waveguide anti-leakage interface device, device includes first rectangular waveguide 1 and PCB substrate 2;

[0007] The first rectangular waveguide 1 is arranged on the first side of the PCB substrate 2, and the first waveguide 21 is arranged through the PCB substrate 2 on the first side of the PCB substrate 2. The center of the first waveguide port 11 of the first rectangular waveguide 1 is aligned with the center of the second waveguide port 211 of the first waveguide 21 on the first side of the PCB substrate 2.

[0008] A periodic structure 22 is arranged around the second waveguide port 211 on the layer where the first side of the PCB substrate 2 is located. When the electromagnetic wave propagates from the first rectangular waveguide 1 through the first waveguide port 11 and the second waveguide port 211 to the first waveguide 21 arranged on the PCB substrate, the periodic structure 22 forms an ideal magnetic wall PMC on the corresponding surface, which surrounds the first waveguide port 11 and the second waveguide port 211 to prevent the electromagnetic wave from leaking out of the gap between the first waveguide port 11 and the second waveguide port 211, thereby ensuring stable transmission of the electromagnetic wave between the first rectangular waveguide 1 and the first waveguide 21 on the PCB substrate 2.

[0009] Further, the cross section of the first rectangular waveguide 1 is rectangular, and the width and height of the cross section are determined based on the requirements of the electromagnetic wave signals of the frequency band to be transmitted.

[0010] The first rectangular waveguide 1 is arranged perpendicular to the PCB substrate 2, and the center line of the propagation direction of the first rectangular waveguide 1 is perpendicular to the PCB substrate 2. The annular side wall 111 of the first waveguide port 11 of the first rectangular waveguide 1 is in the same plane and parallel to the PCB substrate 2.

[0011] Further, the first rectangular waveguide 1 is made of metal CNC machining or based on injection molding of plastic metalization.

[0012] Further, the PCB substrate 2 is a high-frequency PCB board material, and the first waveguide 21 is arranged through the PCB substrate 2 at a position corresponding to the first rectangular waveguide 1 on the PCB substrate 2. The first waveguide 21 meets the size requirements of the electromagnetic wave signals of the frequency band to be transmitted, and also meets the matching requirements of the waveguide interface of the radio frequency chip, so as to ensure stable transmission of the electromagnetic wave between the first waveguide 21 and the radio frequency chip.

[0013] Further, the first waveguide 21 includes a waveguide hole 212 arranged on the PCB substrate 2 and a waveguide wall 213 attached to the waveguide hole 212. The waveguide hole 212 is machined on the PCB substrate 2 according to specific size requirements by a milling cutter or a rotary head. The waveguide wall 213 is a layer of copper plating formed by electroplating and attached to the waveguide hole 212. The first hole ring 214 is formed on the layer where the first side of the PCB substrate 2 is located, and the second hole ring 215 is formed on the layer where the second side of the PCB substrate 2 is located.

[0014] Further, the periodic structure 22 is arranged around the second waveguide port 211 of the first waveguide 21 on the layer where the first side of the PCB substrate 2 is located, the periodic structure 22 is a plurality of regular polygons with equal side length, the distance between the polygons is the same, the center of the polygon is provided with a metalized via hole 221, the metalized via hole 221 is connected to the polygon and the metal ground plate 23 provided on the layer where the second side of the PCB substrate is located, the polygons close to the first hole ring 214 on the layer where the first side is located are connected to or not connected to the first hole ring 214, and the periodic structure 22 and the annular side wall 111 of the first waveguide port 11 of the first rectangular waveguide 1 form an electromagnetic wave leakage prevention structure, wherein the periodic structure 22 is completed together with the PCB waveguide cavity during the production of the PCB substrate 2;

[0015] The periodic structure polygons on the first side of the second waveguide port 211 are connected to the first hole ring 214 of the second waveguide port 211 without leaving a gap, and the periodic structure polygons on the second side of the second waveguide port 211 are connected to the first hole ring 214 or maintain a spacing of no more than 30% of the size of the periodic structure 22, wherein the first side is longer than the second side, and the periodic structure polygons are corresponding polygons of the periodic structure 22;

[0016] The periodic structure 22 around the innermost layer of the first hole ring 214 of the second waveguide port 211 is arranged according to the actual size of the first hole ring 214, allowing the periodic structure 22 around the innermost layer of the first hole ring 214 to have a spacing, and the spacing is blocked by using periodic polygons on the outer layer or by increasing the spacing between the polygons to surround the first hole ring 214 with periodic structure polygons;

[0017] The spacing between the periodic structure polygons is arranged to be equal or unequal spacing according to the actual size of the first hole ring 214 to be enclosed, or a combination of partial equal spacing and partial unequal spacing.

[0018] Further, the side length of the polygon and the spacing between the polygons are determined based on the required operating frequency and the dielectric constant and thickness of the PCB substrate 2;

[0019] Determining the side length of the polygon and the spacing between the polygons based on the required operating frequency and the dielectric constant and thickness of the PCB substrate 2 includes:

[0020] Determining the free space wavelength of the PCB substrate 2 based on the required operating frequency;

[0021] Determining the effective dielectric constant based on the dielectric constant and thickness of the PCB substrate 2;

[0022] Determining the effective wavelength of the PCB substrate 2 based on the free space wavelength and the effective dielectric constant;

[0023] Determining the side length of the polygon and the spacing between the polygons based on the effective wavelength of the PCB substrate 2.

[0024] Further, the PCB substrate 2 adopts a dielectric plate with a dielectric constant of 3.32, a loss tangent of 0.004, and a thickness of 0.088 mm;

[0025] The periodic structure 22 adopts a square patch, the side length of the square patch is 0.91 mm, the patch spacing is 0.12 mm-0.16 mm, and a metal via with a diameter of 0.3 mm is used in the square patch.

[0026] Further, when there is a gap between the first waveguide port 11 of the first rectangular waveguide 1 and the second waveguide port 211 of the first waveguide 21 on the PCB substrate 2, an ideal magnetic wall is formed on the surface of the first waveguide 21 around the second waveguide port 211, so as to add an invisible waveguide cavity surrounded by the ideal magnetic wall between the first waveguide port 11 of the first rectangular waveguide 1 and the second waveguide port 211 of the first waveguide 21 on the PCB substrate 2, prevent electromagnetic waves from leaking from the gap between the first waveguide port 11 of the first rectangular waveguide 1 and the second waveguide port 211 of the first waveguide 21 on the PCB substrate 2, and thus realize stable transmission of electromagnetic waves between the first rectangular waveguide 1 and the first waveguide 21 on the PCB substrate 2.

[0027] Further, when there is a gap of 0.2 mm between the first waveguide port 11 of the first rectangular waveguide 1 and the second waveguide port 211 of the first waveguide 21 on the PCB substrate 2, the transmission loss of the first waveguide 21 on the PCB substrate 2 from the first rectangular waveguide 1 is less than 0.2 dB in the frequency range of 74 GHz-83 GHz.

[0028] Further, when the PCB substrate 2 is adapted to 8 waveguide ports, and there is a gap of 0.2 mm between the waveguide ports, the insertion loss of the 8 channel interfaces is less than 0.25 dB in the frequency range of 75 GHz-82 GHz.

[0029] The millimeter wave waveguide anti-leakage interface device has the following beneficial effects:

[0030] When the electromagnetic wave propagates from the first rectangular waveguide through the first waveguide port to the first waveguide arranged on the PCB substrate, the periodic structure forms an ideal magnetic wall PMC on the corresponding surface, which surrounds the first waveguide port and the second waveguide port, so as to prevent electromagnetic waves from leaking out of the gap between the first waveguide port and the second waveguide port, and ensure stable transmission of electromagnetic waves between the first rectangular waveguide and the first waveguide.

[0031] Moreover, the millimeter wave waveguide anti-leakage interface device designed in the utility model has a wide bandwidth and small loss; the device has good tolerance to the gap, facilitating the production and assembly of the waveguide antenna; in addition, the periodic structure is designed by using the PCB process, which is simple in structure, mature in process, and convenient for integration, can effectively reduce the complexity and production difficulty of the waveguide antenna part mold, thereby reducing the production cost. BRIEF DESCRIPTION OF DRAWINGS

[0032] In order to more clearly illustrate the technical scheme of the embodiments of the utility model, the drawings needed to be used in the embodiments of the utility model will be briefly introduced below, and other drawings can also be obtained by the ordinary skilled in the art without creative labor on the premise that the drawings are not paid.

[0033] Figure 1 A millimeter wave waveguide anti-leakage interface device structure schematic view is provided for the embodiments of the utility model;

[0034] Figure 2 A millimeter wave waveguide anti-leakage interface device structure perspective view is provided for the embodiments of the utility model;

[0035] Figure 3 A millimeter wave waveguide anti-leakage interface device PCB substrate top view is provided for the embodiments of the utility model;

[0036] Figure 4 A millimeter wave waveguide anti-leakage interface device first rectangular waveguide bottom view is provided for the embodiments of the utility model;

[0037] Figure 5 A millimeter wave waveguide anti-leakage interface device structure perspective view adapted to 4 transmitting and 4 receiving radio frequency chips is provided for the embodiments of the utility model;

[0038] Figure 6 A millimeter wave waveguide anti-leakage interface device PCB substrate part structure schematic view adapted to 4 transmitting and 4 receiving radio frequency chips is provided for the embodiments of the utility model;

[0039] Figure 7 A millimeter wave waveguide anti-leakage interface device rectangular waveguide part structure bottom view adapted to 4 transmitting and 4 receiving radio frequency chips is provided for the embodiments of the utility model;

[0040] Figure 8 A millimeter wave waveguide anti-leakage interface device S parameter simulation curve graph is provided for the embodiments of the utility model;

[0041] Figure 9 A millimeter wave waveguide anti-leakage interface device S parameter simulation curve graph adapted to 4 transmitting and 4 receiving radio frequency chips is provided for the embodiments of the utility model. DETAILED DESCRIPTION

[0042] The features and exemplary embodiments of various aspects of this utility model will now be described in detail. To make the objectives, technical solutions, and advantages of this utility model clearer, the following description, in conjunction with the accompanying drawings and embodiments, will provide a further detailed description. It should be understood that the specific embodiments described herein are configured only to explain this utility model and are not configured to limit it. For those skilled in the art, this utility model can be implemented without some of these specific details. The following description of the embodiments is merely intended to provide a better understanding of this utility model by illustrating examples of it.

[0043] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes said element.

[0044] The technical solutions provided by the embodiments of this utility model are described below with reference to the accompanying drawings.

[0045] like Figure 1 As shown, this utility model is a schematic diagram of a millimeter-wave waveguide anti-leakage interface device, which includes a first rectangular waveguide 1 and a PCB substrate 2.

[0046] A first rectangular waveguide 1 is disposed on the first side of the PCB substrate 2. A first waveguide 21 penetrating the PCB substrate 2 is disposed on the first side of the PCB substrate 2. The center of the first waveguide opening 11 of the first rectangular waveguide 1 is aligned with the center of the second waveguide opening 211 of the first waveguide 21 located on the first side of the PCB substrate 2. The first side of the PCB substrate 2 can be understood as... Figure 1 The upper side of PCB substrate 2, and the second side of PCB substrate 2 can be understood as Figure 1 The underside of PCB substrate 2;

[0047] A periodic structure 22 is arranged around the second waveguide port 211 on the first layer of the PCB substrate 2. When electromagnetic waves propagate from the first rectangular waveguide 1 through the first waveguide port 11 and the second waveguide port 211 to the first waveguide 21 on the PCB substrate, the periodic structure 22 forms an ideal magnetic conductor (PMC) on the corresponding surface, surrounding the first waveguide port 11 and the second waveguide port 211. This prevents electromagnetic waves from leaking out from the gap between the first waveguide port 11 and the second waveguide port 211, thereby ensuring stable transmission of electromagnetic waves between the first rectangular waveguide 1 and the first waveguide 21 on the PCB substrate 2. The ideal magnetic conductor (PMC) is a boundary condition commonly used in electromagnetic theory and simulation experiments. It refers to a hypothetical surface that completely reflects the magnetic field without energy loss. Specifically, the characteristic of an ideal magnetic conductor is that the magnetic field component in the normal direction of the surface is zero, and the electric field component in the tangential direction is also zero.

[0048] Combined with appendix Figures 2 to 9 ,right Figure 1 The structural diagram of the millimeter-wave waveguide anti-leakage interface device will be described further.

[0049] In some embodiments, the cross-section of the first rectangular waveguide 1 is rectangular, and the width and height of the cross-section are determined based on the requirements of the electromagnetic wave signal to be transmitted in the desired frequency band.

[0050] The first rectangular waveguide 1 is placed perpendicular to the PCB substrate 2, and its centerline along the propagation direction is perpendicular to the PCB substrate 2. The annular sidewall 111 of the first waveguide port 11 of the first rectangular waveguide 1 is in the same plane and remains parallel to the PCB substrate 2.

[0051] In some embodiments, the first rectangular waveguide 1 is fabricated based on metal CNC machining or based on injection-molded plastic metallization.

[0052] In some embodiments, the PCB substrate 2 is a high-frequency PCB material. A first waveguide 21 is provided on the PCB substrate at a position corresponding to the first rectangular waveguide 1, penetrating through the PCB substrate 2. The first waveguide 21 must meet the size requirements for transmitting electromagnetic waves in the required frequency band, and also meet the matching requirements with the waveguide interface of the radio frequency chip, so as to ensure stable transmission of electromagnetic waves between the first waveguide 21 and the radio frequency chip.

[0053] In some embodiments, the first waveguide 21 includes a waveguide hole 212 disposed on a PCB substrate and a waveguide wall 213 attached to the waveguide hole 212. The waveguide hole 212 is processed on the PCB substrate 2 according to specific dimensional requirements by a milling cutter or a rotary head. The waveguide wall 213 is a copper plating layer formed by electroplating attached to the waveguide hole 212. A first hole ring 214 is formed on the first side layer of the PCB substrate 2, and a second hole ring 215 is formed on the second side layer of the PCB substrate 2.

[0054] In some embodiments, a periodic structure 22 is provided around the second waveguide port 211 of the first waveguide 21 on the first side layer of the PCB substrate 2. The periodic structure 22 consists of multiple regular polygonal patches with equal side lengths and equal distances between them. A metallized via 221 is provided at the center of each patch. The metallized via 221 connects the patch to the metal ground plane 23 on the second side layer of the PCB substrate. Patches close to the first hole ring 214 on the first side layer may or may not be connected to the first hole ring 214. The periodic structure 22 and the annular sidewall 111 of the first waveguide port 11 of the first rectangular waveguide 1 form an electromagnetic wave leakage prevention structure. The periodic structure 22 is manufactured together with the PCB waveguide cavity during the production of the PCB substrate 2.

[0055] The periodic structural patch located on the first side of the second waveguide port 211 is connected to the first hole ring 214 of the second waveguide port 211 without gap. The periodic structural patch located on the second side of the second waveguide port 211 is connected to the first hole ring 214 or maintains a distance not exceeding 30% of the size of the periodic structure 22. The first side is longer than the second side. The periodic structural patch is the patch corresponding to the periodic structure (22).

[0056] The periodic structure 22 surrounding the innermost layer of the first hole ring 214 of the second waveguide port 211 is arranged according to the actual size of the first hole ring 214, allowing a gap to exist around the innermost periodic structure 22 of the first hole ring 214. The gap is sealed by periodic patches on the outer layer, or the periodic structure patches are made to surround the first hole ring 214 by increasing the spacing between the patches.

[0057] The spacing between the periodic structural patches is set to be equal or unequal, or a mixture of partially equal and partially unequal spacing, depending on the actual size of the first hole ring 214 to be surrounded.

[0058] In other words, the periodic structural patch located on the long side of the second waveguide port 211 is connected to the first hole ring 214 of the second waveguide port 211 without gaps, while the periodic structural patch located on the short side of the second waveguide port 211 can be connected to the first hole ring 214 or maintain an appropriate distance, with the maximum distance not exceeding 30% of the periodic structure size.

[0059] Furthermore, the periodic structure surrounding the innermost layer of the first hole ring 214 of the second waveguide port 211 is reasonably arranged according to the actual size of the first hole ring 214. Due to space constraints, a large gap can be allowed in the periodic structure surrounding the innermost layer of the first hole ring 214, but the large gap must be sealed by periodic patches on the outer layer. Alternatively, the periodic structure patches can be reasonably arranged around the first hole ring 214 by appropriately increasing the spacing between the patches.

[0060] The spacing between the periodic structural patches can be set to equal or unequal spacing according to the actual size of the first hole ring 214 to be surrounded, or a mixture of partially equal and partially unequal spacing, but the size of the periodic structural patches is the same.

[0061] In some embodiments, the side length of the patch and the spacing between the patches are determined based on the required operating frequency and the dielectric constant and thickness of the PCB substrate 2;

[0062] The side lengths of the patches and the spacing between them are determined based on the required operating frequency and the dielectric constant and thickness of the PCB substrate 2, including:

[0063] The free space wavelength of PCB substrate 2 is determined based on the required operating frequency;

[0064] The effective dielectric constant is determined based on the dielectric constant and thickness of PCB substrate 2;

[0065] The effective wavelength of PCB substrate 2 is determined based on free space wavelength and effective dielectric constant.

[0066] The side length of the patch and the spacing between patches are determined based on the effective wavelength of the PCB substrate 2.

[0067] In some embodiments, the PCB substrate 2 is a dielectric board with a dielectric constant of 3.32, a loss tangent of 0.004, and a thickness of 0.088 mm;

[0068] The periodic structure 22 uses square patches with a side length of 0.91mm and a patch spacing of 0.12mm-0.16mm. A metal via with a diameter of 0.3mm is used in the center of the square patch.

[0069] In some embodiments, when there is a gap between the first waveguide port 11 of the first rectangular waveguide 1 and the second waveguide port 211 of the first waveguide 21 on the PCB substrate, an ideal magnetic wall is formed on the surface of the first waveguide 21 and surrounds the second waveguide port 211. This serves to add an invisible waveguide cavity formed by the ideal magnetic wall between the first waveguide port 11 of the first rectangular waveguide 1 and the second waveguide port 211 of the first waveguide 21 on the PCB substrate, preventing electromagnetic waves from leaking from the gap between the first waveguide port 11 of the first rectangular waveguide 1 and the second waveguide port 211 of the first waveguide 21 on the PCB substrate, thereby achieving stable transmission of electromagnetic waves between the first rectangular waveguide 1 and the first waveguide 21 on the PCB substrate 2.

[0070] Combination Figure 8 The S-parameter curve of the anti-leakage device based on the square patch periodic structure designed according to this embodiment is shown. It can be seen from the curve that when there is a 0.2mm gap between the first waveguide port 11 of the first rectangular waveguide 1 and the second waveguide port 211 of the first waveguide 21 on the PCB substrate 2, the transmission loss from the first rectangular waveguide 1 to the first waveguide 21 on the PCB substrate in the 74GHz-83GHz frequency band is less than 0.2dB.

[0071] In other words, in some embodiments, when there is a 0.2mm gap between the first waveguide port 11 of the first rectangular waveguide 1 and the second waveguide port 211 of the first waveguide 21 located on the PCB substrate 2, the transmission loss from the first rectangular waveguide 1 to the first waveguide 21 on the PCB substrate in the 74GHz-83GHz frequency band is less than 0.2dB.

[0072] Furthermore, the millimeter-wave waveguide anti-leakage interface device designed in this invention can also be adapted to situations where multiple waveguide ports are simultaneously connected to a PCB substrate. Figure 6 This diagram shows a perspective view of the anti-leakage interface device structure for the interconnection of eight waveguide ports of a 4-transmitter, 4-receiver RF chip according to an embodiment of the present invention. Figure 7 This diagram shows a schematic of the PCB substrate structure of the anti-leakage interface device for the connection of eight waveguide ports of a 4-transmitter, 4-receiver RF chip according to an embodiment of the present invention. Figure 9 The S-parameter simulation curves are based on the leakage-proof interface device for the 4-transmit 4-receive RF chip with 8 waveguide ports designed according to the embodiments of this utility model. It can be seen from the curves that when there is a 0.2mm gap, the insertion loss of the 8 channels in the 75GHz-82GHz frequency band does not exceed 0.25dB.

[0073] This utility model discloses a millimeter-wave waveguide anti-leakage interface device, comprising a first rectangular waveguide and a PCB substrate. The first rectangular waveguide is disposed above the PCB substrate and is perpendicular to the PCB substrate along the electromagnetic wave transmission direction, and is connected to the first waveguide disposed on the PCB substrate. Several periodic structures are arranged around the waveguide opening on the upper side of the first waveguide on the PCB substrate. These periodic structures, which are technologically mature and structurally simple, are arranged on the PCB substrate and cooperate with the annular sidewall of the waveguide opening of the first rectangular waveguide connected to the first waveguide on the PCB substrate to form an ideal magnetic wall around the first rectangular waveguide and the first waveguide connection opening, preventing electromagnetic waves from leaking from the gaps between them, thereby ensuring stable transmission of electromagnetic waves between the first rectangular waveguide and the first waveguide on the PCB substrate.

[0074] The millimeter-wave waveguide anti-leakage interface device of this invention has the following advantages:

[0075] First, the millimeter-wave waveguide anti-leakage interface device designed in this utility model has a wider bandwidth and lower loss;

[0076] Secondly, the millimeter-wave waveguide anti-leakage interface device designed in this utility model has good tolerance for gaps, which facilitates the production and assembly of waveguide antennas.

[0077] Third, the millimeter-wave waveguide anti-leakage interface device designed in this utility model adopts PCB technology to design a periodic structure, which is simple in structure, mature in process, and easy to integrate. It can effectively reduce the complexity and production difficulty of the waveguide antenna part mold, thereby reducing production costs.

[0078] It should be clarified that this utility model is not limited to the specific configurations and processes described above and shown in the figures. For the sake of brevity, detailed descriptions of known methods are omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of this utility model is not limited to the specific steps described and shown. Those skilled in the art can make various changes, modifications, and additions, or change the order of steps, after understanding the spirit of this utility model.

[0079] The functional blocks shown in the above-described structural diagram can be implemented as hardware, software, firmware, or a combination thereof. When implemented in hardware, they can be, for example, electronic circuits, application-specific integrated circuits (ASICs), appropriate firmware, plug-ins, function cards, etc. When implemented in software, the elements of this invention are programs or code segments used to perform the required tasks. The programs or code segments can be stored on a machine-readable medium or transmitted over a transmission medium or communication link via data signals carried on a carrier wave. "Machine-readable medium" can include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, read-only memory (ROM), flash memory, erasable read-only memory (EROM), floppy disks, compact disc read-only memory (CD-ROM), optical disks, hard disks, fiber optic media, radio frequency (RF) links, etc. Code segments can be downloaded via computer networks such as the Internet, intranets, etc.

[0080] It should also be noted that the exemplary embodiments mentioned in this utility model describe some methods or systems based on a series of steps or apparatus. However, this utility model is not limited to the order of the above steps; that is, the steps can be performed in the order mentioned in the embodiments, or in a different order, or several steps can be performed simultaneously.

[0081] The aspects of this disclosure have been described above with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this disclosure. It should be understood that each block in the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, 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, or other programmable data processing apparatus to produce a machine such that these instructions, executable via the processor of the computer or other programmable data processing apparatus, enable the implementation of the functions / actions specified in one or more blocks of the flowchart illustrations and / or block diagrams. Such a processor can be, but is not limited to, a general-purpose processor, a special-purpose processor, a special application processor, or a field-programmable logic circuit. It is also understood that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can also be implemented by special-purpose hardware performing the specified functions or actions, or can be implemented by a combination of special-purpose hardware and computer instructions.

[0082] The above description is merely a specific embodiment of this utility model. Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, modules, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here. It should be understood that the protection scope of this utility model is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this utility model, and these modifications or substitutions should all be covered within the protection scope of this utility model.

Claims

1. A millimeter-wave waveguide anti-leakage interface device, characterized in that, The device includes a first rectangular waveguide (1) and a PCB substrate (2); A first rectangular waveguide (1) is disposed on the first side of the PCB substrate (2). A first waveguide (21) penetrating the PCB substrate (2) is disposed on the first side of the PCB substrate (2). The center of the first waveguide port (11) of the first rectangular waveguide (1) is aligned with the center of the second waveguide port (211) of the first waveguide (21) located on the first side of the PCB substrate (2). A periodic structure (22) is set around the second waveguide port (211) on the first side layer of the PCB substrate (2). When electromagnetic waves propagate from the first rectangular waveguide (1) through the first waveguide port (11) and the second waveguide port (211) to the first waveguide (21) set on the PCB substrate, the periodic structure (22) forms an ideal magnetic wall PMC on the corresponding surface, surrounding the first waveguide port (11) and the second waveguide port (211) to prevent electromagnetic waves from leaking out from the gap between the first waveguide port (11) and the second waveguide port (211), thereby ensuring stable transmission of electromagnetic waves between the first rectangular waveguide (1) and the first waveguide (21) located on the PCB substrate (2).

2. The apparatus according to claim 1, characterized in that, The first rectangular waveguide (1) has a rectangular cross-section, and the width and height of the cross-section are determined based on the requirements of the electromagnetic wave signal to be transmitted in the desired frequency band. The first rectangular waveguide (1) is placed perpendicular to the PCB substrate (2), and its centerline along the propagation direction is perpendicular to the PCB substrate (2). The annular sidewall (111) of the first waveguide port (11) of the first rectangular waveguide (1) is in the same plane and is parallel to the PCB substrate (2). The first rectangular waveguide (1) is made by CNC machining of metal or by metallization of injection-molded plastic.

3. The apparatus according to claim 1, characterized in that, The PCB substrate (2) is a high-frequency PCB material. A first waveguide (21) is provided on the PCB substrate (2) at a position corresponding to the first rectangular waveguide (1). The first waveguide (21) must meet the size requirements for transmitting electromagnetic waves of the required frequency band, and also meet the matching requirements with the waveguide interface of the radio frequency chip, so as to ensure that electromagnetic waves are transmitted stably between the first waveguide (21) and the radio frequency chip.

4. The apparatus according to claim 3, characterized in that, The first waveguide (21) includes a waveguide hole (212) disposed on the PCB substrate (2) and a waveguide wall (213) attached to the waveguide hole (212). The waveguide hole (212) is processed on the PCB substrate (2) according to specific size requirements by a milling cutter or a rotary head. The waveguide wall (213) is a copper plating layer formed by electroplating attached to the waveguide hole (212). A first hole ring (214) is formed on the first side layer of the PCB substrate (2), and a second hole ring (215) is formed on the second side layer of the PCB substrate (2).

5. The apparatus according to claim 1, characterized in that, A periodic structure (22) is provided around the second waveguide port (211) of the first waveguide (21) on the first side layer of the PCB substrate (2). The periodic structure (22) consists of multiple regular polygonal patches with equal side lengths. The patches are spaced at the same distance. A metallized via (221) is provided at the center of the patch. The metallized via (221) connects the patch to the metal ground plane (23) on the second side layer of the PCB substrate. The patch close to the first hole ring (214) on the first side layer is connected to or not connected to the first hole ring (214). The periodic structure (22) and the annular sidewall (111) of the first waveguide port (11) of the first rectangular waveguide (1) form an electromagnetic wave leakage prevention structure. The periodic structure (22) is manufactured together with the PCB waveguide cavity during the production of the PCB substrate (2). The periodic structure patch located on the first side of the second waveguide port (211) is connected to the first hole ring (214) of the second waveguide port (211) without gap, and the periodic structure patch located on the second side of the second waveguide port (211) is connected to the first hole ring (214) or maintains a distance not exceeding 30% of the size of the periodic structure (22). The first side is longer than the second side, and the periodic structure patch is the patch corresponding to the periodic structure (22). The periodic structure (22) surrounding the innermost layer of the first hole ring (214) of the second waveguide (211) is arranged according to the actual size of the first hole ring (214), allowing for a gap around the innermost periodic structure (22) of the first hole ring (214). The gap is sealed by periodic patches on the outer layer, or the periodic structure patches are arranged around the first hole ring (214) by increasing the spacing between the patches. The spacing between the periodic structural patches is set to be equal or unequal, or a mixture of partially equal and partially unequal spacing, depending on the actual size of the first hole ring (214) to be surrounded.

6. The apparatus according to claim 5, characterized in that, The side length of the patch and the spacing between the patches are determined based on the required operating frequency and the dielectric constant and thickness of the PCB substrate (2); The side length of the patches and the spacing between the patches are determined based on the required operating frequency and the dielectric constant and thickness of the PCB substrate (2), including: The free space wavelength of the PCB substrate (2) is determined based on the required operating frequency; The effective dielectric constant is determined based on the dielectric constant and thickness of the PCB substrate (2); The effective wavelength of the PCB substrate (2) is determined based on the free space wavelength and the effective dielectric constant; The side length of the patch and the spacing between patches are determined based on the effective wavelength of the PCB substrate (2).

7. The apparatus according to claim 6, characterized in that, The PCB substrate (2) is a dielectric board with a dielectric constant of 3.32, a loss tangent of 0.004, and a thickness of 0.088 mm. The periodic structure (22) uses square patches with a side length of 0.91 mm and a patch spacing of 0.12 mm to 0.16 mm. A metal via with a diameter of 0.3 mm is used in the middle of the square patch.

8. The apparatus according to claim 6, characterized in that, When there is a gap between the first waveguide port (11) of the first rectangular waveguide (1) and the second waveguide port (211) of the first waveguide (21) on the PCB substrate (2), an ideal magnetic wall will be formed on the surface of the first waveguide (21) and surround the second waveguide port (211) to add an invisible waveguide cavity formed by the ideal magnetic wall between the first waveguide port (11) of the first rectangular waveguide (1) and the second waveguide port (211) of the first waveguide (21) on the PCB substrate (2), so as to prevent electromagnetic waves from leaking from the gap between the first waveguide port (11) of the first rectangular waveguide (1) and the second waveguide port (211) of the first waveguide (21) on the PCB substrate (2), thereby realizing the stable transmission of electromagnetic waves between the first rectangular waveguide (1) and the first waveguide (21) on the PCB substrate (2).

9. The apparatus according to claim 1, characterized in that, When there is a 0.2mm gap between the first waveguide port (11) of the first rectangular waveguide (1) and the second waveguide port (211) of the first waveguide (21) on the PCB substrate (2), the transmission loss of the first waveguide (21) from the first rectangular waveguide (1) to the first waveguide (21) on the PCB substrate (2) in the 74GHz-83GHz frequency band is less than 0.2dB.

10. The apparatus according to claim 9, characterized in that, When the PCB substrate (2) is adapted to 8 waveguide ports, and there is a 0.2mm gap between the waveguide ports, the insertion loss of the 8 channel interfaces is less than 0.25dB in the 75GHz-82GHz frequency band.

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