Grounded coplanar waveguide transmission line and radar device

Abstract

The application provides a ground coplanar waveguide transmission line and a radar device. The ground coplanar waveguide transmission line comprises a substrate, a center strip located on the upper side of the substrate, a first upper side ground plane located on the left side of the center strip, a second upper side ground plane located on the right side of the center strip, a lower side ground plane located on the lower side of the substrate, a first metal through hole penetrating the substrate and located between the first upper side ground plane and the lower side ground plane, the first upper side ground plane being connected to the lower side ground plane through the first metal through hole, a second metal through hole penetrating the substrate and located between the second upper side ground plane and the lower side ground plane, the second upper side ground plane being connected to the lower side ground plane through the second metal through hole, and a metalized via hole not penetrating the substrate and located on the lower side of the center strip, the metalized via hole being connected to the center strip and not connected to the lower side ground plane. According to the technical scheme, the crosstalk between GCPW transmission lines can be significantly reduced.

Description

Technical Field

[0001] This application relates to the field of transmission line technology, and in particular to a grounded coplanar waveguide transmission line and radar equipment. Background Technology

[0002] With the rapid development of terahertz technology in the field of wireless communication, GCPW (Grounded Coplanar Waveguide) transmission lines are also widely used and have broad application prospects. GCPW transmission lines are planar circuit transmission lines that are compact in size, flexible in routing, have low dispersion, and low loss. They can be easily connected in series and parallel with passive and active devices, which can significantly improve circuit density and transmission efficiency.

[0003] When using GCPW transmission lines to achieve wireless communication, the signals between each radio frequency channel need to be transmitted independently without crosstalk. This requires high isolation between GCPW transmission lines. However, the characteristics of GCPW transmission lines result in poor isolation performance, making it impossible to guarantee that the signals between radio frequency channels will not crosstalk, leading to poor signal transmission performance of GCPW transmission lines. Summary of the Invention

[0004] This application provides a grounded coplanar waveguide transmission line, the grounded coplanar waveguide transmission line comprising:

[0005] substrate;

[0006] A central conductive strip located on the upper side of the substrate, a first upper ground plane located to the left of the central conductive strip, and a second upper ground plane located to the right of the central conductive strip;

[0007] The lower ground plane located on the lower side of the substrate;

[0008] A first metal via is located between the first upper ground plane and the lower ground plane, penetrating the substrate, and the first upper ground plane is connected to the lower ground plane through the first metal via;

[0009] A second metal via is located between the second upper ground plane and the lower ground plane, penetrating the substrate, and the second upper ground plane is connected to the lower ground plane through the second metal via;

[0010] A metallized via located below the central conductive strip that does not penetrate the substrate, the metallized via being connected to the central conductive strip and not connected to the lower ground plane.

[0011] For example, the substrate is a single substrate, and the depth of the metallized via is no greater than M times the thickness of the substrate; wherein M is a value greater than 0 and less than 1.

[0012] For example, the substrate includes an upper sub-substrate, a lower sub-substrate, and a prepreg PP layer located between the upper sub-substrate and the lower sub-substrate; wherein the metallized via penetrates the upper sub-substrate and contacts the PP layer, and the metallized via does not contact the lower sub-substrate.

[0013] For example, the grounded coplanar waveguide transmission line includes an array of metallized vias located below the central conductor, and the array of metallized vias includes multiple metallized vias; wherein the spacing between adjacent metallized vias is less than the wavelength of the electromagnetic wave transmitted by the grounded coplanar waveguide transmission line.

[0014] For example, the width of the metallized via is smaller than the width of the central conductor.

[0015] For example, the shape of the metallized via includes a round hole shape, a square hole shape, or an elliptical hole shape.

[0016] For example, the grounded coplanar waveguide transmission line is applied to a parallel transmission line structure;

[0017] The parallel transmission line structure includes a first port, a second port, a third port, a fourth port, a first grounded coplanar waveguide transmission line, and a first ordinary waveguide transmission line, wherein the first grounded coplanar waveguide transmission line and the first ordinary waveguide transmission line are a pair of adjacent parallel transmission lines;

[0018] The first port and the second port are connected through the first grounded coplanar waveguide transmission line, and the third port and the fourth port are connected through the first ordinary waveguide transmission line.

[0019] For example, the grounded coplanar waveguide transmission line is applied to a parallel transmission line structure;

[0020] The parallel transmission line structure sequentially includes a first grounded coplanar waveguide transmission line, a first ordinary waveguide transmission line, a second grounded coplanar waveguide transmission line, and a second ordinary waveguide transmission line; or, the parallel transmission line structure sequentially includes a first ordinary waveguide transmission line, a first grounded coplanar waveguide transmission line, a second ordinary waveguide transmission line, and a second grounded coplanar waveguide transmission line; wherein, the first grounded coplanar waveguide transmission line and the second grounded coplanar waveguide transmission line are isolated by an ordinary waveguide transmission line.

[0021] The parallel transmission line structure further includes a first port, a second port, a third port, a fourth port, a fifth port, a sixth port, a seventh port, and an eighth port; wherein the first port and the second port are connected through the first grounded coplanar waveguide transmission line, the third port and the fourth port are connected through the second grounded coplanar waveguide transmission line, the fifth port and the sixth port are connected through the first ordinary waveguide transmission line, and the seventh port and the eighth port are connected through the second ordinary waveguide transmission line.

[0022] For example, the first or second ordinary waveguide transmission line includes:

[0023] Substrate; a central conductive strip on the upper side of the substrate, a first upper ground plane on the left side of the central conductive strip, a second upper ground plane on the right side of the central conductive strip; and a lower ground plane on the lower side of the substrate.

[0024] A first metal via is located between the first upper ground plane and the lower ground plane, penetrating the substrate, and the first upper ground plane is connected to the lower ground plane through the first metal via;

[0025] A second metal via is located between the second upper ground plane and the lower ground plane, penetrating the substrate, and the second upper ground plane is connected to the lower ground plane through the second metal via.

[0026] This application provides a radar device, which includes a radio frequency port and an antenna, wherein the radio frequency port and the antenna are connected via a grounded coplanar waveguide transmission line as described above.

[0027] As can be seen from the above technical solutions, in this embodiment of the application, a novel GCPW transmission line (grounded coplanar waveguide transmission line) is designed. This novel GCPW transmission line includes a metallized via that does not penetrate the substrate and is located on the lower side of the center guide strip. The metallized via is connected to the center guide strip and is not connected to the lower ground plane (i.e., there is no electrical connection). By adding a metallized via to the center guide strip, the radio frequency isolation is improved, and the radio frequency isolation between GCPW transmission lines is significantly improved. This can significantly reduce crosstalk between GCPW transmission lines, increase the isolation between radio frequency channels, and enable the signals between each radio frequency channel to be transmitted independently without crosstalk between them. This can improve the signal transmission effect of the GCPW transmission line, while retaining the characteristics of GCPW transmission line such as compact size, flexible routing, low dispersion, and low loss. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments of this application or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings of the embodiments of this application.

[0029] Figure 1 This is a schematic diagram of the structure of a conventional waveguide transmission line in one embodiment of this application;

[0030] Figure 2 This is a schematic diagram of the structure of a GCPW transmission line in one embodiment of this application;

[0031] Figure 3A This is a schematic diagram of a design for a conventional waveguide transmission line according to one embodiment of this application;

[0032] Figure 3B This is a schematic diagram of a design for a GCPW transmission line according to one embodiment of this application;

[0033] Figure 4 This is a schematic diagram of the structure of a GCPW transmission line in one embodiment of this application;

[0034] Figure 5A This is a schematic diagram of a parallel transmission line structure in one embodiment of this application;

[0035] Figure 5B This is a schematic diagram of the field distribution in one embodiment of this application;

[0036] Figure 5C This is a schematic diagram of a parallel transmission line structure in one embodiment of this application;

[0037] Figure 5D This is a schematic diagram of the field distribution in one embodiment of this application;

[0038] Figure 5E This is a schematic diagram of S-parameters used to characterize crosstalk in one embodiment of this application;

[0039] Figure 6A This is a schematic diagram of a parallel transmission line structure in one embodiment of this application;

[0040] Figure 6B This is a schematic diagram of S-parameters used to characterize crosstalk in one embodiment of this application;

[0041] Figure 6C This is a schematic diagram of S-parameters used to characterize crosstalk in one embodiment of this application. Detailed Implementation

[0042] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to limit the application. The singular forms “a,” “the,” and “the” as used in this application and claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to any and all possible combinations comprising one or more of the associated listed items.

[0043] It should be understood that although the terms first, second, third, etc., may be used to describe various information in embodiments of this application, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, without departing from the scope of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" may also be interpreted as "when," "when," or "in response to a determination."

[0044] This application proposes a grounded coplanar waveguide transmission line (GCPW transmission line) to improve radio frequency isolation by adding metallized vias to the center conductor. This significantly improves the radio frequency isolation between GCPW transmission lines, reduces crosstalk between GCPW transmission lines, and increases the isolation between radio frequency channels, enabling signals in each radio frequency channel to be transmitted independently without crosstalk between them.

[0045] See Figure 1 The diagram shown is a schematic of a typical waveguide transmission line, which includes:

[0046] Substrate 11. Substrate 11 is the basic material for manufacturing PCBs. Substrate 11 can be a copper-clad laminate. In the manufacturing process of single-sided and double-sided printed circuit boards, selective hole processing, chemical copper plating, electroplating, etching and other processes are performed on the substrate material - copper-clad laminate (CCL) to obtain circuit patterns.

[0047] A central conductive strip 12, a first upper ground plane 13 to the left of the central conductive strip 12, and a second upper ground plane 14 to the right of the central conductive strip 12 are located on the upper side of the substrate 11. The first upper ground plane 13 and the second upper ground plane 14 are located on the upper side of the substrate 11. The central conductive strip 12 can be an energy space formed by free electrons, that is, the energy range of electrons moving freely within the solid structure. The first upper ground plane 13 and the second upper ground plane 14 can refer to a reference plane (zero potential point) or a loop path, that is, a layer used as a ground wire. For example, the ground plane in this embodiment can also be called a ground plane.

[0048] The lower ground plane 15 is located on the underside of the substrate 11. The lower ground plane 15 can refer to a reference plane (zero potential point) or a loop path, that is, the lower ground plane 15 is also used as a ground layer.

[0049] A first metal via 16 is located between the first upper ground plane 13 and the lower ground plane 15, penetrating the substrate 11, and the first upper ground plane 13 is connected to the lower ground plane 15 through the first metal via 16. The upper part of the first metal via 16 contacts the first upper ground plane 13, and the lower part of the first metal via 16 contacts the lower ground plane 15, thereby penetrating the substrate 11 and connecting the first upper ground plane 13 and the lower ground plane 15.

[0050] A second metal via 17 is located between the second upper ground plane 14 and the lower ground plane 15, penetrating the substrate 11, and the second upper ground plane 14 is connected to the lower ground plane 15 through the second metal via 17. The upper part of the second metal via 17 contacts the second upper ground plane 14, and the lower part of the second metal via 17 contacts the lower ground plane 15, thereby penetrating the substrate 11 and connecting the second upper ground plane 14 and the lower ground plane 15.

[0051] and Figure 1 The difference is that this application proposes a novel grounded coplanar waveguide transmission line. In order to distinguish it from ordinary waveguide transmission lines, the novel grounded coplanar waveguide transmission line is called a grounded coplanar waveguide transmission line (i.e., GCPW transmission line). By adding metallized vias to the center conductor, the radio frequency isolation is improved, which can significantly reduce crosstalk between GCPW transmission lines and increase the isolation between radio frequency channels.

[0052] See Figure 2 The diagram shown is a structural schematic of a GCPW transmission line, which may include:

[0053] Substrate 21. Substrate 21 is the basic material for manufacturing PCB. Substrate 21 can be a copper-clad laminate, a single-sided printed circuit board, or a double-sided printed circuit board. During manufacturing, selective processing such as hole processing, chemical copper plating, electroplating, and etching are performed on the substrate material - copper-clad laminate - to obtain the circuit pattern.

[0054] A central conductive strip 22 is located on the upper side of the substrate 21, a first upper ground plane 23 is located to the left of the central conductive strip 22, and a second upper ground plane 24 is located to the right of the central conductive strip 22. The first upper ground plane 23 and the second upper ground plane 24 are located on the upper side of the substrate 21. The central conductive strip 22 can be an energy space formed by free electrons, that is, the energy range of electrons moving freely within the solid structure. The first upper ground plane 23 and the second upper ground plane 24 can refer to a reference plane (zero potential point) or a loop path, that is, a layer used as a ground wire.

[0055] The lower ground plane 25 is located on the underside of the substrate 21. The lower ground plane 25 can refer to a reference plane (zero potential point) or a loop path, that is, the lower ground plane 25 is also used as a ground layer.

[0056] A first metal via 26 is located between the first upper ground plane 23 and the lower ground plane 25, penetrating the substrate 21, and the first upper ground plane 23 is connected to the lower ground plane 25 through the first metal via 26. The upper part of the first metal via 26 contacts the first upper ground plane 23, and the lower part of the first metal via 26 contacts the lower ground plane 25, thereby penetrating the substrate 21 and connecting the first upper ground plane 23 and the lower ground plane 25.

[0057] A second metal via 27 is located between the second upper ground plane 24 and the lower ground plane 25, penetrating the substrate 21, and the second upper ground plane 24 is connected to the lower ground plane 25 through the second metal via 27. The upper part of the second metal via 27 contacts the second upper ground plane 24, and the lower part of the second metal via 27 contacts the lower ground plane 25, thereby penetrating the substrate 21 and connecting the second upper ground plane 24 and the lower ground plane 25.

[0058] A metallized via 28 located below the central guide strip 22 but not penetrating the substrate 21 is connected to the central guide strip 22, but not connected to the lower ground plane 25. That is, the metallized via 28 has no electrical connection to the lower ground plane 25, or the metallized via 28 has no electrical connection to the lower ground plane 25. The upper part of the metallized via 28 contacts the central guide strip 22, but the lower part of the metallized via 28 does not contact the lower ground plane 25, meaning it does not penetrate the substrate 21, thus preventing the central guide strip 22 and the lower ground plane 25 from being connected.

[0059] In summary, it can be seen that Figure 2 The GCPW transmission line shown is Figure 1 Compared to the ordinary waveguide transmission line shown, an additional metallized via 28 is added, that is, metallized via 28 is distributed below the center conductor 22. The metallized via 28 is connected to the center conductor 22, but is not electrically connected to the lower ground plane 25.

[0060] In one possible implementation, substrate 21 can be a single, monolithic substrate, i.e., substrate 21 is composed of a single PCB layer. In this case, the GCPW transmission line can be found in [reference needed]. Figure 2 As shown.

[0061] For example, the depth of the metallized via 28 is no greater than M times the thickness of the substrate 21. M can be a value greater than 0 and less than 1, such as 0.5, 0.6, 0.66, 0.7, 0.8, etc. There is no restriction on the value of M; it can be configured based on experience. Taking 0.66 as an example, the depth of the metallized via 28 will typically not exceed 0.66 times the thickness of the substrate 21. In this case, the metallized via 28 can also be called a metallized blind via. For example, the depth of the metallized via 28 is 0.127 mm, and the thickness of the substrate 21 is 0.254 mm. Of course, this is just an example of the depth of the metallized via 28 and the thickness of the substrate 21, and there are no limitations on this.

[0062] For example, the GCPW transmission line includes a metallized via array located below the center conductor 22, and the metallized via array may include multiple metallized vias 28, that is, multiple metallized vias 28 are periodically distributed below the center conductor 22, such as 3, 4, or 5 metallized vias 28 distributed below the center conductor 22.

[0063] For multiple metallized vias 28, the spacing between adjacent metallized vias 28 can be smaller than the wavelength of the electromagnetic wave transmitted by the GCPW transmission line, such as a spacing much smaller than the wavelength of the electromagnetic wave transmitted by the GCPW transmission line. For example, assuming the wavelength of the electromagnetic wave transmitted by the GCPW transmission line is C, the spacing between adjacent metallized vias 28 can be less than N*C, where N can be a value greater than 0 and less than 1, such as 0.1, 0.01, 0.001, etc., and there is no restriction on the value of N.

[0064] For example, the spacing between the second metallized via 28 and the first metallized via 28 is less than N*C, the spacing between the third metallized via 28 and the second metallized via 28 is less than N*C, and so on.

[0065] For example, the width (or diameter) of the metallized via 28 can be smaller than the width of the center conductor 22. For instance, for multiple metallized vias 28, the widths of different metallized vias 28 can be the same, or the widths of different metallized vias 28 can be different. For each metallized via 28, the width of the metallized via 28 can be smaller than the width of the center conductor 22. By making the width of the metallized via 28 smaller than the width of the center conductor 22, the metallized via 28 will not disrupt the electrical continuity of the center conductor 22.

[0066] For example, the shape of the metallized via 28 may include, but is not limited to, a circular, square, or elliptical shape. Of course, the above are just a few examples, and the shape of the metallized via 28 is not limited. For instance, for multiple metallized vias 28, the shapes of different metallized vias 28 may be the same, or the shapes of different metallized vias 28 may be different. For example, the first metallized via 28 may be circular, the second metallized via 28 may be square, the third metallized via 28 may be circular, the fourth metallized via 28 may be elliptical, and so on.

[0067] See Figure 3A As shown, this is for Figure 1 The diagram below shows the design of a conventional waveguide transmission line. According to transmission line theory, the propagation speed of electromagnetic waves in a conventional waveguide transmission line is denoted as wave velocity v. Wave velocity v is determined by the frequency w of the electromagnetic wave and the propagation constant γ, as shown in the following expression: The propagation constant γ is determined by the distributed capacitance C1 and inductance L1 on a typical waveguide transmission line, as shown in the following expression: γ = jw(L1C1) 1 / 2 .

[0068] See Figure 3B As shown, this is for Figure 2 The schematic diagram of the GCPW transmission line design shows that after introducing the metallized via 28, since there is no electrical connection between the metallized via 28 and the lower ground plane 25, an additional capacitance C2 exists between the metallized via 28 and the lower ground plane 25. Based on this, according to transmission line theory, the propagation speed of electromagnetic waves in the GCPW transmission line is denoted as wave speed v, which is determined by the frequency w and propagation constant γ of the electromagnetic wave, as shown in the following expression: The propagation constant γ is determined by the distributed capacitance C' and inductance L1 on the GCPW transmission line, as shown in the following expression: γ = jw(L1C') 1 / 2 Furthermore, the distributed capacitance C' can also be determined by the following expression:

[0069] Based on the above expression, it can be seen that... Figure 3B and Figure 3A In contrast, the change in distributed capacitance C' compared to distributed capacitance C1 leads to a change in the propagation constant γ, which in turn alters the wave velocity v of the electromagnetic wave. Based on this, by designing the spacing between adjacent metallized vias 28 to be much smaller than the wavelength of the electromagnetic wave transmitted through the GCPW transmission line, the introduced capacitance can conform to the infinitesimal element assumption in transmission line theory. By introducing an array of metallized vias, the wave velocity v of the GCPW transmission line can be controlled.

[0070] Based on the above expression, it can be seen that the smaller the distance between the metallized via 28 and the lower ground plane 25, the larger the introduced capacitance (i.e., distributed capacitance C'). Therefore, by designing the depth of the metallized via 28 to be no greater than M times the thickness of the substrate 21 (for example, the depth of the metallized via 28 should not be greater than 0.66 times the thickness of the substrate 21), additional resonance effects can be avoided.

[0071] In addition, the diameter / width of the metallized via 28 can be smaller than the width of the center conductor 22. This design allows the metallized via 28 to maintain the electrical continuity of the center conductor 22.

[0072] In one possible implementation, substrate 21 can be a distributed substrate, i.e., substrate 21 is composed of two or more PCBs (taking two PCBs as an example). In this case, the GCPW transmission line can be found in [reference needed]. Figure 4 As shown. The substrate 21 may include an upper sub-substrate 21-1, a lower sub-substrate 21-2, and a PP (PrePreg) layer 21-3 located between the upper sub-substrate 21-1 and the lower sub-substrate 21-2.

[0073] In addition to the upper sub-substrate 21-1, the lower sub-substrate 21-2, and the PP layer 21-3, it may also include: a central conductive strip 22 located on the upper side of the upper sub-substrate 21-1, a first upper ground plane 23 located to the left of the central conductive strip 22, and a second upper ground plane 24 located to the right of the central conductive strip 22, wherein the first upper ground plane 23 and the second upper ground plane 24 are located on the upper side of the upper sub-substrate 21-1. A lower ground plane 25 is located on the lower side of the lower sub-substrate 21-2.

[0074] The GCPW transmission line may also include a first metal via 26 located between the first upper ground plane 23 and the lower ground plane 25, and the first metal via 26 includes a first metal via 26-1 penetrating the upper sub-substrate 21-1 and a first metal via 26-2 penetrating the lower sub-substrate 21-2, the first metal via 26-1 being located on the upper sub-substrate 21-1 and the first metal via 26-2 being located on the lower sub-substrate 21-2.

[0075] The GCPW transmission line may also include a second metal via 27 located between the second upper ground plane 24 and the lower ground plane 25, and the second metal via 27 includes a second metal via 27-1 penetrating the upper sub-substrate 21-1 and a second metal via 27-2 penetrating the lower sub-substrate 21-2, the second metal via 27-1 being located on the upper sub-substrate 21-1 and the second metal via 27-2 being located on the lower sub-substrate 21-2.

[0076] The GCPW transmission line may also include a metallized via 28 located below the central conductor 22. The metallized via 28 is connected to the central conductor 22 and penetrates the upper sub-substrate 21-1 to contact the PP layer 21-3 (since it penetrates the upper sub-substrate 21-1, the metallized via 28 can also be called a metallized through-hole). The metallized via 28 is not in contact with the lower sub-substrate 21-2. Since the metallized via 28 is not in contact with the lower sub-substrate 21-2, the metallized via 28 is not connected to the lower ground plane 25, that is, the metallized via 28 is not electrically connected to the lower ground plane 25, or the metallized via 28 is not electrically connected to the lower ground plane 25.

[0077] In the above design, the metallized via 28 penetrates the upper sub-substrate 21-1 and contacts the PP layer 21-3, which means that the metallized via can be directly designed on the upper sub-substrate, thereby simplifying the implementation of the metallized via 28.

[0078] For example, the GCPW transmission line includes a metallized via array located below the center conductor 22, and the metallized via array may include multiple metallized vias 28, that is, multiple metallized vias 28 are periodically distributed below the center conductor 22, such as 3, 4, or 5 metallized vias 28 distributed below the center conductor 22.

[0079] For multiple metallized vias 28, the spacing between adjacent metallized vias 28 can be smaller than the wavelength of the electromagnetic wave transmitted by the GCPW transmission line, such as a spacing much smaller than the wavelength of the electromagnetic wave transmitted by the GCPW transmission line. For example, assuming the wavelength of the electromagnetic wave transmitted by the GCPW transmission line is C, the spacing between adjacent metallized vias 28 can be less than N*C, where N can be a value greater than 0 and less than 1, such as 0.1, 0.01, 0.001, etc., and there is no restriction on the value of N.

[0080] For example, the width (or diameter) of the metallized via 28 can be smaller than the width of the center conductor 22. For instance, for multiple metallized vias 28, the widths of different metallized vias 28 can be the same, or the widths of different metallized vias 28 can be different. For each metallized via 28, the width of the metallized via 28 can be smaller than the width of the center conductor 22. By making the width of the metallized via 28 smaller than the width of the center conductor 22, the metallized via 28 will not disrupt the electrical continuity of the center conductor 22.

[0081] For example, the shape of the metallized via 28 may include, but is not limited to, a circular hole shape, a square hole shape, or an elliptical hole shape. Of course, the above are just a few examples, and the shape of the metallized via 28 is not limited. For instance, for multiple metallized vias 28, the shapes of different metallized vias 28 may be the same, or the shapes of different metallized vias 28 may be different. For example, the first metallized via 28 may be a circular hole shape, the second metallized via 28 may be a square hole shape, and so on.

[0082] In one possible implementation, the GCPW transmission line is used as a carrier for transmitting radio frequency signals, for example, by printing a strip structure on a PCB board to transmit electromagnetic waves. The application scenarios for GCPW transmission lines are not limited, as long as they are used to transmit radio frequency signals. The following examples illustrate the applicable scenarios for GCPW transmission lines; however, these are merely examples and are not intended to be limiting.

[0083] Application Scenario 1: GCPW transmission lines are used in radar, such as millimeter-wave radar.

[0084] Radar (such as millimeter-wave radar) is increasingly playing a vital role in fields such as automotive driver assistance, safety protection, and healthcare. Radar consists of an RF port and an antenna. During normal operation, the RF port and antenna need to be interconnected via a transmission line. Based on this, GCPW transmission lines can be applied to radar, allowing the RF port and antenna to be connected via GCPW transmission lines. For example, the RF port and antenna can be connected via... Figure 2 The GCPW transmission line connection shown can also be achieved through... Figure 4 The GCPW transmission line connection is shown.

[0085] Because GCPW transmission lines are compact, flexible in routing, have low dispersion and low loss, they are easy to connect in series and parallel with passive and active devices. Therefore, when GCPW transmission lines are applied to radar, circuit density and transmission efficiency can be significantly improved.

[0086] In Figure 2 or Figure 4 When the GCPW transmission line shown is applied to radar, the radio frequency isolation can be improved by adding metallized vias to the center conductor. This can significantly improve the radio frequency isolation between GCPW transmission lines, thereby significantly reducing crosstalk between GCPW transmission lines, increasing the isolation between radio frequency channels, and enabling signals between each radio frequency channel to be transmitted independently without crosstalk between them.

[0087] Application Scenario 2: GCPW transmission lines are used in parallel transmission line structures, i.e., a pair of adjacent parallel transmission lines. For example, a parallel transmission line structure includes a first port, a second port, a third port, a fourth port, a first GCPW transmission line, and a first ordinary waveguide transmission line (the first ordinary waveguide transmission line can also be replaced by a second GCPW transmission line; the first and second GCPW transmission lines are novel GCPW transmission lines, see [link]). Figure 2 or Figure 4 As shown, the first ordinary waveguide transmission line is a standard GCPW transmission line, see [link / reference]. Figure 1 As shown, taking the first ordinary waveguide transmission line as an example, the first GCPW transmission line and the first ordinary waveguide transmission line are a pair of adjacent parallel transmission lines. The first port and the second port are connected through the first GCPW transmission line, and the third port and the fourth port are connected through the first ordinary waveguide transmission line.

[0088] For example, see Figure 5A The diagram shown is a schematic of a parallel transmission line structure. The parallel transmission line structure uses transmission line 1 and transmission line 2, both of which are ordinary waveguide transmission lines (denoted as conventional GCPW 1 and conventional GCPW 2). The structure of an ordinary waveguide transmission line can be found in [reference needed]. Figure 1 As shown.

[0089] For example, port 1 is connected to port 2 via transmission line 1 (standard GCPW 1), and port 3 is connected to port 4 via transmission line 2 (standard GCPW 2). The length of the parallel section between transmission line 1 and transmission line 2 is 50mm (this can be adjusted according to actual conditions), and the distance between the center conductors of transmission line 1 and transmission line 2 is 1.1mm (this can be adjusted according to actual conditions), which approximately corresponds to a quarter wavelength.

[0090] This parallel transmission line structure can be used to detect crosstalk between transmission line 1 and transmission line 2. Ideally, the signal entering from port 1 will be transmitted efficiently to port 2. However, due to the crosstalk between transmission lines 1 and 2, some electromagnetic energy is coupled to transmission line 2 as it propagates along transmission line 1. This energy is then received by ports 3 and 4. Therefore, the coupling coefficient between ports 1 and 4 (and the coupling coefficient between ports 1 and 3) represents the crosstalk between transmission lines 1 and 2.

[0091] See Figure 5B The diagram shows the field distribution when port 1 is excited. Significant electromagnetic energy distribution can be detected at ports 3 and 4, indicating significant coupling between transmission line 1 and transmission line 2. This is confirmed by the field distribution at the parallel section, as shown below. Figure 5B As shown in the illustration.

[0092] For example, see Figure 5C The diagram shows a parallel transmission line structure, which uses transmission line 1' and transmission line 2'. Transmission line 1' is a novel GCPW transmission line (i.e., the first GCPW transmission line, denoted as the novel GCPW). The structure of the novel GCPW transmission line is shown below. Figure 2 or Figure 4 As shown. Transmission line 2' can be a novel GCPW transmission line (i.e., the second GCPW transmission line) or a conventional waveguide transmission line (i.e., the first conventional waveguide transmission line). Hereafter, we will take the conventional waveguide transmission line as an example and refer to transmission line 2' as a conventional GCPW. The structure of a conventional waveguide transmission line can be found in [reference needed]. Figure 1 As shown.

[0093] For example, port 1' (i.e., the first port) is connected to port 2' (i.e., the second port) via transmission line 1' (new type GCPW), and port 3' (i.e., the third port) is connected to port 4' (i.e., the fourth port) via transmission line 2' (conventional GCPW). The length of the parallel segment between transmission line 1' and transmission line 2' can be 50mm (which can be set according to actual conditions), and the distance between the center conductors of transmission line 1' and transmission line 2' can be 1.1mm (which can be set according to actual conditions), approximately corresponding to a quarter wavelength.

[0094] On the parallel section between transmission line 1' and transmission line 2', since transmission line 1' is a new type of GCPW, multiple metallized vias are distributed on the lower side of the center conductor of transmission line 1'. The spacing of these metallized vias can be 0.4mm (which can be set according to actual conditions), the depth of these metallized vias is 0.127mm (which can be set according to actual conditions), and the thickness of the substrate is 0.254mm (which can be set according to actual conditions).

[0095] This parallel transmission line structure can be used to detect crosstalk between transmission line 1' and transmission line 2'. Under the excitation of port 1', see... Figure 5D The diagram shows the field distribution when port 1' is excited. Significant energy suppression can be detected at ports 3' and 4'. Figure 5D The illustration shows the field distribution of the parallel segments. From this field distribution, it can be seen that electromagnetic energy can only propagate within the region of transmission line 1', and almost no electromagnetic energy distribution can be observed within transmission line 2', indicating that the crosstalk between the two is well suppressed.

[0096] To quantify the crosstalk suppression effect after adopting the new GCPW, see [link / reference]. Figure 5E The diagram shown illustrates the S-parameters (i.e., transmission coefficients) used to characterize crosstalk. For Figure 5A Given a parallel transmission line structure, the transmission coefficients for port 1 and port 4 are given, i.e., S. 41,for Figure 5C Given a parallel transmission line structure, the transmission coefficients for ports 1' and 4' are given, i.e., S. 4’1’ By comparing the S-parameters of the two, it can be seen that the new GCPW reduces crosstalk between transmission lines by about 15dB, which is a 30-fold reduction, thus effectively suppressing crosstalk.

[0097] Application Scenario 3: GCPW transmission lines are applied to parallel transmission line structures, which can be transmission line arrays (e.g., arrays of 4, 6, or 8 transmission lines; a 4-transmission-line array will be used as an example hereafter). For instance, a parallel transmission line structure can sequentially include a first GCPW transmission line (see...). Figure 2 or Figure 4 (as shown), first ordinary waveguide transmission line (see...) Figure 1 As shown, the first ordinary waveguide transmission line can also be replaced by a GCPW transmission line, a second GCPW transmission line, and a second ordinary waveguide transmission line (the second ordinary waveguide transmission line can also be replaced by a GCPW transmission line). Alternatively, the parallel transmission line structure can sequentially include a first ordinary waveguide transmission line, a first GCPW transmission line, a second ordinary waveguide transmission line, and a second GCPW transmission line. The first GCPW transmission line and the second GCPW transmission line are isolated by an ordinary waveguide transmission line.

[0098] The parallel transmission line structure may also include a first port, a second port, a third port, a fourth port, a fifth port, a sixth port, a seventh port, and an eighth port. The first and second ports can be connected via a first GCPW transmission line, the third and fourth ports via a second GCPW transmission line, the fifth and sixth ports via a first ordinary waveguide transmission line, and the seventh and eighth ports via a second ordinary waveguide transmission line.

[0099] For example, see Figure 6A The diagram on the right shows a parallel transmission line structure. This structure uses transmission lines 1', 2', 3', and 4', all of which are conventional waveguide transmission lines (denoted as GCPW). The structure of a conventional waveguide transmission line can be found in [reference needed]. Figure 1 As shown, port A1' is connected to port B1' via transmission line 1', port A2' is connected to port B2' via transmission line 2', port A3' is connected to port B3' via transmission line 3', and port A4' is connected to port B4' via transmission line 4'. In contrast, an array consisting of transmission lines 1', 2', 3', and 4' was used to examine crosstalk between conventional GCPW transmission lines.

[0100] See Figure 6A The left side shows a schematic diagram of a parallel transmission line structure, which uses transmission lines 1, 2, 3, and 4. Transmission line 1 is a novel GCPW transmission line (i.e., the first GCPW transmission line), see [link to diagram]. Figure 2 or Figure 4 As shown. Transmission line 2 can be a novel GCPW transmission line or a first ordinary waveguide transmission line. Taking the first ordinary waveguide transmission line as an example, see [link to example]. Figure 1 As shown. Transmission line 3 is a novel GCPW transmission line (i.e., the second GCPW transmission line). Transmission line 2 can be a novel GCPW transmission line or a second ordinary waveguide transmission line; the second ordinary waveguide transmission line is used as an example.

[0101] Port A1 (i.e., the first port) can be connected to port B1 (i.e., the second port) through transmission line 1; port A2 (i.e., the fifth port) can be connected to port B2 (i.e., the sixth port) through transmission line 2; port A3 (i.e., the third port) can be connected to port B3 (i.e., the fourth port) through transmission line 3; and port A4 (i.e., the seventh port) can be connected to port B4 (i.e., the eighth port) through transmission line 4.

[0102] On the parallel section between transmission lines 1 and 2, transmission line 1 is a new type of GCPW, and multiple metallized vias are distributed on the lower side of the center conductor of transmission line 1. On the parallel section between transmission lines 3 and 4, transmission line 3 is a new type of GCPW, and multiple metallized vias are distributed on the lower side of the center conductor of transmission line 3.

[0103] To quantify the crosstalk suppression effect after adopting the new GCPW, see [link / reference]. Figure 6B The diagram shown is a schematic of the S-parameters (i.e., transmission coefficients) used to characterize crosstalk. Figure 6B Give the coupling coefficient of the adjacent transmission lines when port A3 is excited, i.e., S. B2A3 S B2A3 This represents the strength of crosstalk received on adjacent transmission lines when a signal enters from the new GCPW transmission line. It can be seen that when port A3 is excited, the crosstalk strength on adjacent transmission lines is approximately -28 dB. In contrast, when port A3' is excited, the coupling coefficient of adjacent transmission lines can be S. B2’A3’ That is, the crosstalk intensity received on adjacent transmission lines is approximately -14dB. The simulation results above show that the new GCPW transmission line provides a crosstalk suppression effect of approximately 14dB.

[0104] Similarly, see Figure 6C As shown, when port A2 is excited, the coupling coefficient of adjacent transmission lines is S. B1A2, representing the crosstalk strength to adjacent transmission lines when the signal enters from a conventional GCPW. In contrast, when port A2' is excited, the coupling coefficient of adjacent transmission lines is S. B1’A2’ The simulation results above show that the new GCPW transmission line provides a crosstalk suppression effect of about 14dB, which is significant.

[0105] As can be seen from the above technical solutions, this embodiment designs a novel GCPW transmission line. This novel GCPW transmission line includes a metallized via that does not penetrate the substrate and is located below the center conductor. The metallized via is connected to the center conductor and is not connected to the ground plane below. By adding a metallized via to the center conductor, the RF isolation is improved, significantly increasing the RF isolation between GCPW transmission lines. This can significantly reduce crosstalk between GCPW transmission lines, increase the isolation between RF channels, and enable independent signal transmission between each RF channel without crosstalk between them. This can improve the signal transmission effect of the GCPW transmission line while retaining the compact size, flexible routing, low dispersion, and low loss characteristics of the GCPW transmission line. It is easy to achieve series and parallel connection with passive and active devices, significantly improving circuit density and transmission efficiency.

[0106] Based on the same application concept as the aforementioned grounded coplanar waveguide transmission line (i.e., GCPW transmission line), this application proposes a grounded coplanar waveguide transmission line, which includes:

[0107] substrate;

[0108] A central conductive strip located on the upper side of the substrate, a first upper ground plane located to the left of the central conductive strip, and a second upper ground plane located to the right of the central conductive strip;

[0109] The lower ground plane located on the lower side of the substrate;

[0110] A first metal via is located between the first upper ground plane and the lower ground plane, penetrating the substrate, and the first upper ground plane is connected to the lower ground plane through the first metal via;

[0111] A second metal via is located between the second upper ground plane and the lower ground plane, penetrating the substrate, and the second upper ground plane is connected to the lower ground plane through the second metal via;

[0112] A metallized via located below the central conductive strip that does not penetrate the substrate, the metallized via being connected to the central conductive strip and not connected to the lower ground plane.

[0113] For example, the substrate is a single substrate, and the depth of the metallized via is no greater than M times the thickness of the substrate; wherein M is a value greater than 0 and less than 1.

[0114] For example, the substrate includes an upper sub-substrate, a lower sub-substrate, and a prepreg PP layer located between the upper sub-substrate and the lower sub-substrate; wherein the metallized via penetrates the upper sub-substrate and contacts the PP layer, and the metallized via does not contact the lower sub-substrate.

[0115] For example, the grounded coplanar waveguide transmission line includes an array of metallized vias located below the central conductor, and the array of metallized vias includes multiple metallized vias; wherein the spacing between adjacent metallized vias is less than the wavelength of the electromagnetic wave transmitted by the grounded coplanar waveguide transmission line.

[0116] For example, the width of the metallized via is smaller than the width of the central conductor.

[0117] For example, the shape of the metallized via includes a round hole shape, a square hole shape, or an elliptical hole shape.

[0118] For example, the grounded coplanar waveguide transmission line is applied to a radar, which includes an RF port and an antenna, and the RF port and the antenna are connected through the grounded coplanar waveguide transmission line.

[0119] For example, the grounded coplanar waveguide transmission line is applied to a parallel transmission line structure;

[0120] The parallel transmission line structure includes a first port, a second port, a third port, a fourth port, a first grounded coplanar waveguide transmission line, and a first ordinary waveguide transmission line, wherein the first grounded coplanar waveguide transmission line and the first ordinary waveguide transmission line are a pair of adjacent parallel transmission lines;

[0121] The first port and the second port are connected through the first grounded coplanar waveguide transmission line, and the third port and the fourth port are connected through the first ordinary waveguide transmission line.

[0122] For example, the grounded coplanar waveguide transmission line is applied to a parallel transmission line structure;

[0123] The parallel transmission line structure sequentially includes a first grounded coplanar waveguide transmission line, a first ordinary waveguide transmission line, a second grounded coplanar waveguide transmission line, and a second ordinary waveguide transmission line; or, the parallel transmission line structure sequentially includes a first ordinary waveguide transmission line, a first grounded coplanar waveguide transmission line, a second ordinary waveguide transmission line, and a second grounded coplanar waveguide transmission line; wherein, the first grounded coplanar waveguide transmission line and the second grounded coplanar waveguide transmission line are isolated by an ordinary waveguide transmission line.

[0124] The parallel transmission line structure further includes a first port, a second port, a third port, a fourth port, a fifth port, a sixth port, a seventh port, and an eighth port; wherein the first port and the second port are connected through the first grounded coplanar waveguide transmission line, the third port and the fourth port are connected through the second grounded coplanar waveguide transmission line, the fifth port and the sixth port are connected through the first ordinary waveguide transmission line, and the seventh port and the eighth port are connected through the second ordinary waveguide transmission line.

[0125] For example, the first or second ordinary waveguide transmission line includes:

[0126] substrate;

[0127] A central conductive strip located on the upper side of the substrate, a first upper ground plane located to the left of the central conductive strip, and a second upper ground plane located to the right of the central conductive strip;

[0128] The lower ground plane located on the underside of the substrate;

[0129] A first metal via is located between the first upper ground plane and the lower ground plane, penetrating the substrate, and the first upper ground plane is connected to the lower ground plane through the first metal via;

[0130] A second metal via is located between the second upper ground plane and the lower ground plane, penetrating the substrate, and the second upper ground plane is connected to the lower ground plane through the second metal via.

[0131] As can be seen from the above technical solutions, in this embodiment of the application, a novel GCPW transmission line (grounded coplanar waveguide transmission line) is designed. This novel GCPW transmission line includes a metallized via that does not penetrate the substrate and is located on the lower side of the center guide strip. The metallized via is connected to the center guide strip and is not connected to the lower ground plane (i.e., there is no electrical connection). By adding a metallized via to the center guide strip, the radio frequency isolation is improved, and the radio frequency isolation between GCPW transmission lines is significantly improved. This can significantly reduce crosstalk between GCPW transmission lines, increase the isolation between radio frequency channels, and enable the signals between each radio frequency channel to be transmitted independently without crosstalk between them. This can improve the signal transmission effect of the GCPW transmission line, while retaining the characteristics of GCPW transmission line such as compact size, flexible routing, low dispersion, and low loss.

[0132] Based on the same application concept as the aforementioned grounded coplanar waveguide transmission line (i.e., GCPW transmission line), this application proposes a radar device, which may include an RF port and an antenna, and the RF port and the antenna are connected through the aforementioned grounded coplanar waveguide transmission line (i.e., GCPW transmission line).

[0133] The above description is merely an embodiment of this application and is not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A grounded coplanar waveguide transmission line, characterized in that, The grounded coplanar waveguide transmission line includes: substrate; A central conductive strip located on the upper side of the substrate, a first upper ground plane located to the left of the central conductive strip, and a second upper ground plane located to the right of the central conductive strip; The lower ground plane located on the lower side of the substrate; A first metal via is located between the first upper ground plane and the lower ground plane, penetrating the substrate, and the first upper ground plane is connected to the lower ground plane through the first metal via; A second metal via is located between the second upper ground plane and the lower ground plane, penetrating the substrate, and the second upper ground plane is connected to the lower ground plane through the second metal via; A metallized via located below the central conductive strip that does not penetrate the substrate, the metallized via being connected to the central conductive strip and not connected to the lower ground plane.

2. The grounded coplanar waveguide transmission line according to claim 1, characterized in that, The substrate is a single integral substrate, and the depth of the metallized via is no greater than M times the thickness of the substrate; wherein M is a value greater than 0 and less than 1.

3. The grounded coplanar waveguide transmission line according to claim 1, characterized in that, The substrate includes an upper sub-substrate, a lower sub-substrate, and a prepreg PP layer located between the upper sub-substrate and the lower sub-substrate; wherein the metallized via penetrates the upper sub-substrate and contacts the PP layer, and the metallized via does not contact the lower sub-substrate.

4. The grounded coplanar waveguide transmission line according to claim 1, characterized in that, The grounded coplanar waveguide transmission line includes an array of metallized vias located below the central conductor, and the array of metallized vias includes multiple metallized vias; wherein the spacing between adjacent metallized vias is less than the wavelength of the electromagnetic wave transmitted by the grounded coplanar waveguide transmission line.

5. The grounded coplanar waveguide transmission line according to claim 1, characterized in that, The width of the metallized via is smaller than the width of the central conductor.

6. The grounded coplanar waveguide transmission line according to claim 1, characterized in that, The shape of the metallized via includes a round hole, a square hole, or an elliptical hole.

7. The grounded coplanar waveguide transmission line according to any one of claims 1-6, characterized in that, The grounded coplanar waveguide transmission line is applied to a parallel transmission line structure; The parallel transmission line structure includes a first port, a second port, a third port, a fourth port, a first grounded coplanar waveguide transmission line, and a first ordinary waveguide transmission line, wherein the first grounded coplanar waveguide transmission line and the first ordinary waveguide transmission line are a pair of adjacent parallel transmission lines; The first port and the second port are connected through the first grounded coplanar waveguide transmission line, and the third port and the fourth port are connected through the first ordinary waveguide transmission line.

8. The grounded coplanar waveguide transmission line according to any one of claims 1-6, characterized in that, The grounded coplanar waveguide transmission line is applied to a parallel transmission line structure; The parallel transmission line structure sequentially includes a first grounded coplanar waveguide transmission line, a first ordinary waveguide transmission line, a second grounded coplanar waveguide transmission line, and a second ordinary waveguide transmission line; or, the parallel transmission line structure sequentially includes a first ordinary waveguide transmission line, a first grounded coplanar waveguide transmission line, a second ordinary waveguide transmission line, and a second grounded coplanar waveguide transmission line; wherein, the first grounded coplanar waveguide transmission line and the second grounded coplanar waveguide transmission line are isolated by an ordinary waveguide transmission line. The parallel transmission line structure further includes a first port, a second port, a third port, a fourth port, a fifth port, a sixth port, a seventh port, and an eighth port; wherein the first port and the second port are connected through the first grounded coplanar waveguide transmission line, the third port and the fourth port are connected through the second grounded coplanar waveguide transmission line, the fifth port and the sixth port are connected through the first ordinary waveguide transmission line, and the seventh port and the eighth port are connected through the second ordinary waveguide transmission line.

9. The grounded coplanar waveguide transmission line according to claim 8, characterized in that, The first or second ordinary waveguide transmission line includes: substrate; A central conductive strip located on the upper side of the substrate, a first upper ground plane located to the left of the central conductive strip, and a second upper ground plane located to the right of the central conductive strip; The lower ground plane located on the underside of the substrate; A first metal via is located between the first upper ground plane and the lower ground plane, penetrating the substrate, and the first upper ground plane is connected to the lower ground plane through the first metal via; A second metal via is located between the second upper ground plane and the lower ground plane, penetrating the substrate, and the second upper ground plane is connected to the lower ground plane through the second metal via.

10. A radar device, characterized in that, The radar device includes a radio frequency port and an antenna, and the radio frequency port and the antenna are connected by a grounded coplanar waveguide transmission line according to any one of claims 1-6.

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