Dual ground metal via all-metal integrated waveguide structure

Abstract

The application discloses a double-ground full-metal integrated waveguide structure without metal through holes, which comprises a plurality of metal plates, and the plurality of metal plates are connected in a stack to form a self-enclosed structure; a top metal plate and a bottom metal plate are ground structures; two internal metal plates are partially cut to form a cavity structure filled with air; and a microwave radio frequency circuit is arranged on a metal plate clamped between the two metal plates to realize the cavity structure of the MIW. The full-metal integrated structure of the application completely eliminates dielectric loss, and is beneficial to realizing lower loss and higher quality factor of the MIW circuit.

Description

Technical Field

[0001] This invention relates to the field of radio frequency microwave terahertz circuit technology, and in particular to a via-free double ground metal-integrated waveguide (MIW). Background Technology

[0002] Substrate integrated waveguides (SIWs) are highly efficient microwave and millimeter-wave transmission structures that combine the advantages of traditional waveguides and printed circuit board (PCB) technologies (Chen XP, WuK. Substrate integrated waveguide filters: Design techniques and structure innovations[J]. IEEE Microwave Magazine, 2014, 15(6): 121-133). SIWs are widely used in various fields such as communications, radar, sensors, and satellite systems, and are particularly favored in 5G communications, millimeter-wave imaging, and high-frequency test equipment due to their superior transmission performance and lower manufacturing costs.

[0003] With technological advancements, SIW will continue to play a vital role in future high-frequency circuit designs. SIW's significant advantages, including low loss, compactness, and ease of integration, make it an ideal choice for high-frequency circuit design. This structure not only efficiently transmits signals but also allows for convenient integration with other microwave components (such as filters and amplifiers), making it suitable for the implementation of dense integrated circuits.

[0004] Despite its many advantages, SIW also faces some limitations in certain applications. For example, although it has a good frequency response, the bandwidth of SIW may be limited at high frequencies, and it also has higher dielectric losses. Furthermore, the open structure of SIW makes it susceptible to interference from the external environment.

[0005] Furthermore, for SIW applications in high-frequency short circuits, the process requirements for metal vias are relatively high, and the conductivity and size of the vias have a significant impact on the SIW circuit in the high-frequency range. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings and defects of the prior art and provide a dual-ground metal-free through-hole all-metal integrated waveguide structure based on the Metal Integrated Suspension Wire Platform (MISL) design.

[0007] A dual-ground, metal-free, through-hole all-metal integrated waveguide structure includes multiple metal plates stacked together to form a self-encapsulating structure. The top and bottom metal plates form the ground plane structure. The two internal metal plates are partially cut off to form an air-filled cavity structure. Microwave radio frequency circuits are located on the metal plate sandwiched between the two metal plates forming the cavity structure to realize the cavity structure of MIW.

[0008] Each of the aforementioned metal plates is made from a good conductor / a poor conductor with copper cladding on its surface through a metallization process.

[0009] The microwave radio frequency circuit includes a MIW resonator with a non-metallized through-hole structure.

[0010] In this MIW resonator, multiple resonators are coupled together through a slotted wire structure.

[0011] Each of the MIW resonators includes an electric wall formed by a short-circuit structure and a magnetic wall formed by a slotted wire structure.

[0012] The MIW resonator includes a fifth-order Chebyshev filter, and each resonator consists of two electric walls and two magnetic walls.

[0013] The feeding method of the MIW resonator includes waveguide feeding or SIW feeding.

[0014] The MIW resonator is directly fed through an SMA connector.

[0015] In this process, multi-layer circuit boards formed by stacking multiple metal plates are connected by rivets / soldering to form a self-encapsulated structure.

[0016] The metal plate has at least five layers.

[0017] The dual-ground metal-free via-hole all-metal integrated waveguide structure of the present invention has a completely self-encapsulated structure, which can effectively shield electromagnetic signal interference; the all-metal integrated structure completely eliminates dielectric loss, making it particularly suitable for high-frequency circuit design; due to the use of multilayer process, its core circuit can be connected to the metal shell without any metallized vias, and can achieve the electrical boundary (electric wall) conditions that traditional SIW requires metallized vias to achieve. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the dual-ground metal-free through-hole all-metal integrated waveguide structure of the present invention;

[0019] Figure 2 This is a schematic diagram of a fifth-order Chebyshev filter with a dual-ground, metal-free, through-hole, all-metal integrated waveguide structure according to the present invention.

[0020] Figure 3 This is a schematic diagram of various parts of the filter product based on the dual-ground metal-free through-hole all-metal integrated waveguide structure of the present invention.

[0021] Figure 4 This is a schematic diagram of the simulation and test results of a filter designed based on the dual-ground metal-free through-hole all-metal integrated waveguide structure (MIW) of this invention. Detailed Implementation

[0022] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0023] The dual-ground, metal-free, through-hole all-metal integrated waveguide structure of this invention is based on the Metal Integrated Suspension Line Platform (MISL) design. (See [link to relevant documentation]). Figure 1 As shown, a five-layer metal plate is used as an example, but it is not limited to this.

[0024] like Figure 1 As shown, the dual-ground, metal-free, through-hole all-metal integrated waveguide structure adopts a multi-layer metal plate structure, with metal plates M1 to M5 (M1-M5) arranged sequentially from top to bottom. The core circuit is located on metal plate M3. Metal plates M1 and M5 constitute the ground structure. Parts of metal plates M2 and M4 are cut off to form air-filled cavity structures, forming a symmetrical frame structure with discontinuous peripherals and symmetrically separated at both ends. The core circuit is a microwave radio frequency circuit, such as a MIW resonator.

[0025] The multi-layer circuit board formed by the multi-layer metal plates is connected by rivets or soldering to form a self-encapsulated structure. When rivets are used, rivet holes 10 are pre-made on each metal plate.

[0026] The thickness of each metal plate can be customized to any size according to actual needs; they can be the same or different, but their length and width dimensions are the same.

[0027] Figure 2 This is a schematic diagram of a fifth-order Chebyshev filter with a dual-ground, metal-free, through-hole, all-metal integrated waveguide structure according to the present invention, as shown below. Figure 2 As shown, the fifth-order Chebyshev filter based on MIW design has five resonators, each consisting of two electric walls and two magnetic walls, without any metallized via structures. Figure 2As shown in the embodiment of the application, in the MIW resonator, each resonator is replaced by a short-circuit structure instead of the electric wall formed by metallized vias in the traditional SIW, and a magnetic wall is formed by a slotted wire structure; the resonators are coupled to each other through the slotted wire structure; the fifth-order Chebyshev filter designed based on MIW, due to the adoption of an all-metal structure, allows the two ends of the MIW resonator to be easily grounded without any metallized vias for grounding.

[0028] Specifically, such as Figure 2 As shown in the figure, the part enclosed by the dashed line represents five resonators arranged in a row, namely the first resonator 1, the second resonator 2, the third resonator 3, the fourth resonator 4, and the fifth resonator 5. The grounding structure 17 corresponding to each resonator is located at the upper and lower ends of each resonator. The power supply structure 18 is located at two sections of the metal plate. There are six slots on the metal plate, and the axis of the six slots is perpendicular to the length direction of the metal plate. They are the first slot 11, the second slot 12, the third slot 13, the third slot 14, the fourth slot 15, and the sixth slot 16. Among them, the two slots on both sides have the same width, and the four slots in the middle have the same width, which is greater than the two slots on both sides.

[0029] Unlike traditional SIW filters, which require the use of metallized vias to form a closed cavity and coupling through opening windows in the cavity, the MIW filter proposed in this application uses a novel slotted wire structure for coupling. This structure easily achieves a larger coupling coefficient, resulting in a wider bandwidth. Furthermore, the slotted wire structure is easy to fabricate and is simpler to manufacture than metallized vias in the millimeter-wave and terahertz fields, while also exhibiting better stability.

[0030] In the embodiments of this application, the MIW structure can be waveguide fed or conventional SIW fed (such as...). Figure 3 (As shown). Its multi-layered self-encapsulating structure enables excellent electromagnetic signal shielding performance.

[0031] The all-metal integrated waveguide structure in this embodiment completely eliminates dielectric loss, which is beneficial for MIW circuits to achieve lower loss and higher quality factor.

[0032] Figure 3 This is a schematic diagram of various parts of the filter product based on the dual-ground metal-free through-hole all-metal integrated waveguide structure of the present invention, namely, the structural schematic diagram of each metal plate (M1-M5) of the filter and the schematic diagram of the packaged MIW filter, which can be directly fed using the classic SMA connector.

[0033] Figure 4 This is a schematic diagram illustrating the simulation and test results of a filter designed based on the dual-ground metal-free through-hole all-metal integrated waveguide structure (MIW) of this invention. Figure 4The simulation and test results show that the filter designed based on the dual-ground metal-free through-hole all-metal integrated waveguide structure (MIW) of this invention has an in-passband insertion loss of less than 1dB, a return loss of less than -15dB, and a bandwidth of greater than 5%. It exhibits excellent performance.

[0034] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention.

[0035] Therefore, the embodiments should be regarded as exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of the equivalents of the claims be included within the invention.

[0036] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A dual-ground, metal-free, through-hole all-metal integrated waveguide structure, characterized in that, It includes multiple metal plates, which are stacked and connected to form a self-encapsulated structure. The top and bottom metal plates are ground structures. The two internal metal plates are partially cut to form an air-filled cavity structure. Microwave radio frequency circuits are sandwiched between the two metal plates forming the cavity structure to realize the cavity structure of MIW. The microwave radio frequency circuit includes a MIW resonator with a non-metallized via structure; each MIW resonator consists of two electric walls and two magnetic walls; each resonator has an electric wall formed by a short-circuit structure and a magnetic wall formed by a slotted wire structure; multiple resonators in the MIW resonator are coupled together through the slotted wire structure.

2. The dual-ground, metal-free, through-hole all-metal integrated waveguide structure according to claim 1, characterized in that, Each of the aforementioned metal plates is made from a good conductor / a poor conductor with copper plating on the surface through a metallization process.

3. The dual-ground, metal-free, through-hole all-metal integrated waveguide structure according to claim 1, characterized in that, The MIW resonator includes a fifth-order Chebyshev filter, and each resonator consists of two electric walls and two magnetic walls.

4. The dual-ground, metal-free, through-hole all-metal integrated waveguide structure according to claim 1, characterized in that, The feeding method for the MIW resonator includes waveguide feeding or SIW feeding.

5. The dual-ground, metal-free, through-hole all-metal integrated waveguide structure according to claim 1, characterized in that, The MIW resonator is directly fed through an SMA connector.

6. The dual-ground, metal-free, through-hole all-metal integrated waveguide structure according to claim 1, characterized in that, Multi-layer circuit boards formed by stacking multiple metal plates are connected by rivets / soldering to form a self-encapsulated structure.

7. The dual-ground, metal-free, through-hole all-metal integrated waveguide structure according to claim 1, characterized in that, The metal plate has at least five layers.

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