Substrate integrated slow-wave waveguide structure and design method thereof

Abstract

The invention relates to the technical field of microwaves and millimeter waves, in particular to a substrate integrated slow wave waveguide structure and a design method thereof, the structure comprises an upper metal layer, a lower metal layer, a dielectric substrate arranged between the upper metal layer and the lower metal layer, and two rows of metalized through holes penetrating through the dielectric substrate and connecting the upper metal layer and the lower metal layer; a periodic microstructure unit array is arranged on the inner surface, facing the dielectric substrate, of the upper metal layer and / or the lower metal layer; the periodic microstructure unit array is used for being coupled with a quasi TE10 mode electromagnetic field transmitted in the waveguide structure to generate a slow wave effect, so that the phase velocity of electromagnetic waves is reduced in a preset working frequency band. The invention provides a substrate integrated slow-wave waveguide structure and a design method thereof, and aims to solve the technical problems that in the SIW technology, the physical size is large, miniaturization is difficult to achieve in a low-frequency band, high performance and low cost are difficult to consider at the same time, the design process depends on simulation, and the efficiency is not high.

Description

Technical Field

[0001] This invention relates to the field of microwave and millimeter-wave technology, specifically to a substrate-integrated slow-wave waveguide structure and its design method. Background Technology

[0002] In microwave and millimeter-wave communication and radar systems, waveguide structures are crucial components for signal transmission. Traditional waveguide structures typically employ a simple combination of metal layers and dielectric substrates. While effective in transmitting electromagnetic waves, they suffer from excessively high phase velocities in some applications, potentially leading to signal distortion during transmission and impacting system performance and stability. Furthermore, existing waveguide technologies often lack effective means of controlling electromagnetic wave propagation characteristics, making it difficult to meet the demands of high-frequency, high-speed communication.

[0003] To address these issues, researchers have recently begun exploring the use of microstructure arrays to manipulate the electromagnetic field distribution in waveguides. This method effectively couples with the electromagnetic field in the waveguide, thereby enabling the adjustment of the phase velocity. However, existing microstructure designs often suffer from structural complexity, high manufacturing costs, and poor adaptability to operating frequency bands, limiting their widespread adoption in practical applications. Summary of the Invention

[0004] In order to overcome the shortcomings and deficiencies of the existing technology, the present invention aims to provide a substrate integrated slow wave waveguide structure and its design method, which aims to solve the technical problems of SIW technology, such as large physical size, difficulty in miniaturization in low frequency band, difficulty in balancing high performance and low cost, and low efficiency due to reliance on simulation in the design process.

[0005] This invention is achieved through the following technical solution:

[0006] In a first aspect, the present invention discloses a substrate-integrated slow waveguide structure, including an upper metal layer, a lower metal layer, a dielectric substrate disposed between the upper metal layer and the lower metal layer, and two rows of metallized vias penetrating the dielectric substrate and connecting the upper and lower metal layers. A periodic microstructure unit array is provided on the inner surface of the upper metal layer and / or lower metal layer facing the dielectric substrate. The periodic microstructure unit array is used to couple with the quasi-TE10 mode electromagnetic field transmitted in the waveguide structure to generate a slow wave effect, thereby reducing the phase velocity of the electromagnetic wave within a preset operating frequency band.

[0007] In conjunction with the first aspect, the periodic microstructure unit is at least one or a combination of grooves, ridges, slotted resonant rings, complementary slotted resonant rings, and interdigitated capacitor structures.

[0008] In conjunction with the first aspect, the periodic microstructure unit array is further disposed in the central axis region of the waveguide structure along the electromagnetic wave propagation direction.

[0009] In conjunction with the first aspect, the period of the periodic microstructure unit array is further described as a non-uniform period or a chirped period.

[0010] Secondly, this invention discloses a design method for a substrate-integrated slow waveguide structure, which includes the following steps: S100. Determine the initial size parameters of the waveguide structure based on the preset operating center frequency, bandwidth, and target slow wave coefficient; S200. Establish a parameterized electromagnetic model of the periodic microstructure unit and quantitatively characterize its resonance characteristics and coupling strength; S300. Based on the quantitative characterization, construct a global transmission response model for the periodic microstructure unit array; S400. An optimization algorithm is used to adjust the geometric parameters of the parameterized electromagnetic model and the array arrangement so that the performance of the global transmission response model within the preset operating frequency band meets the design requirements.

[0011] In conjunction with the second aspect, further, in step S200, the step of quantitatively characterizing the periodic microstructure unit is as follows: The microstructure unit can be equivalently represented as a two-port network connected in parallel on a transmission line, with its susceptance... Determined by the following formula:

[0012] in, The operating angular frequency; For microstructure units at angular frequency Complex susceptance below; The imaginary unit; The static background susceptance for the non-resonant portion; The coupling coefficient; The natural resonant angular frequency of the unit; The loaded quality factor of the unit.

[0013] In conjunction with the second aspect, further, in step S400, the optimization algorithm solves the following multi-objective weighted integral cost function. To achieve this, use the minimum value:

[0014] in, This is a vector containing all the geometric parameters to be optimized; For about the parameter vector The cost function value; Preset operating angular frequency range; The speed of light in a vacuum; For angular frequency and parameters The phase velocity of electromagnetic waves under these conditions; The target slow wave coefficient; It is a frequency domain weighting function; The input port reflection coefficient of the waveguide structure; These are the weighting factors for the two optimization objectives.

[0015] In conjunction with the second aspect, further, the frequency domain weighting function The mathematical formula is one of the following: Gaussian weighted function, inverse Chebyshev weighted function, or piecewise higher-order polynomial weighted function; The mathematical formula for the Gaussian weighted function is:

[0016] in, The center angular frequency of the operating frequency band is defined as follows: ; It is a natural exponential function. The standard deviation of the Gaussian function; The mathematical formula for the inverse Chebyshev weighted function is:

[0017] in, Let n be a Chebyshev polynomial of the first kind; n is the order of the polynomial. It is a positive integer; It is a fractional expression; The mathematical formula for the piecewise higher-order polynomial weighted function is:

[0018]

[0019]

[0020] in, and For two in the total operating frequency band Angular frequency value within; Let be the highest power in the polynomial expansion of the central interval, and be a non-negative integer. In polynomials The multiplication coefficient of the term; Let be the highest order of the polynomial in the marginal interval; In polynomials The multiplication coefficient of the term.

[0021] Thirdly, the present invention discloses an electronic device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the design method of the substrate integrated slow waveguide structure as described above.

[0022] Fourthly, the present invention discloses a computer-readable storage medium having a computer program stored thereon. The program is executed by the processor to implement the design method of the substrate-integrated slow waveguide structure as described above.

[0023] The beneficial effects of this invention are: This invention discloses a substrate-integrated slow-wave waveguide structure, design method, electronic device, and storage medium. By setting a periodic microstructure unit array on the inner surface of the upper or lower metal layer, efficient electromagnetic field coupling and slow-wave effect are achieved. This structure utilizes the coupling between the quasi-TE10 mode electromagnetic field in the waveguide and the microstructure to effectively control the phase velocity of electromagnetic waves, significantly slow down electromagnetic wave transmission, and improve energy concentration and control capability within a preset operating frequency band. This design features simple manufacturing process, flexible adjustment, and superior performance, greatly satisfying the requirements of high-frequency integrated circuits for high-speed, low-loss, and high-sensitivity signal transmission. Attached Figure Description

[0024] The present invention will be further described with reference to the accompanying drawings, but the embodiments in the drawings do not constitute any limitation on the present invention. For those skilled in the art, other drawings can be obtained based on the following drawings without creative effort.

[0025] Figure 1 This is a flowchart illustrating a design method for a substrate-integrated slow waveguide structure according to an embodiment of the present invention.

[0026] Figure 2 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention.

[0027] Figure 3 This is a schematic diagram of a storage medium provided in an embodiment of the present invention. Detailed Implementation

[0028] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0029] Example 1 This embodiment discloses a substrate-integrated slow waveguide structure, including an upper metal layer, a lower metal layer, a dielectric substrate disposed between the upper metal layer and the lower metal layer, and two rows of metallized vias penetrating the dielectric substrate and connecting the upper and lower metal layers; A periodic microstructure unit array is provided on the inner surface of the upper metal layer and / or lower metal layer facing the dielectric substrate. The periodic microstructure unit array is used to couple with the quasi-TE10 mode electromagnetic field transmitted in the waveguide structure to generate a slow wave effect, thereby reducing the phase velocity of the electromagnetic wave within a preset operating frequency band.

[0030] Two rows of parallel metallized vias penetrate the dielectric substrate, connecting the upper and lower metal layers to form the sidewalls of the waveguide, thus defining the lateral propagation space of electromagnetic waves. In this embodiment, the diameter of the metallized vias can be set to 0.5 mm, the via spacing can be set to 1.0 mm, and the distance between the centerlines of the two rows of vias, i.e., the effective width of the SIW, can be set to 6.0 mm, so that it mainly operates in the X-band (8-12 GHz). Microstrip line transition structures are provided at both ends of the waveguide structure for signal input and output ports.

[0031] The core innovation of this embodiment lies in the fact that a set of periodic microstructure unit arrays are etched along the central axis of the waveguide on the inner surface of the upper metal layer, i.e., the side facing the dielectric substrate. In this embodiment, the microstructure unit is preferably a series of transverse rectangular grooves perpendicular to the wave propagation direction. The length of each groove can be 4.0 mm, the width can be 0.2 mm, and the period of the array (i.e., the distance between the centers of adjacent grooves) can be set to 1.5 mm.

[0032] Its working principle is as follows: When a quasi-TE10 mode electromagnetic wave propagates in the waveguide structure, its electric field component is mainly concentrated in the central region of the waveguide and its direction is perpendicular to the upper and lower metal layers. The transverse groove array set on the central axis will strongly couple with this main electric field component. The introduction of each groove is equivalent to adding a small additional capacitor in parallel on the equivalent transmission line of the SIW. Due to the periodic arrangement of the array, this capacitive loading effect is coherently superimposed, which significantly increases the equivalent capacitance per unit length of the entire waveguide, thereby effectively reducing the phase velocity of the electromagnetic wave and producing a significant slow wave effect.

[0033] Near the center frequency of 10 GHz, the equivalent refractive index of a conventional SIW is approximately 1.3, mainly determined by the dielectric constant of the substrate material. In contrast, the SIW of this embodiment achieves an equivalent refractive index of approximately 2.1, an improvement of over 60% compared to the conventional structure. This means that at the same operating frequency, the electromagnetic wave wavelength in this embodiment is significantly compressed, providing strong technical support for the miniaturization design of components such as filters, couplers, and antennas based on this structure.

[0034] Furthermore, the periodic microstructure unit is at least one or a combination of grooves, ridges, slotted resonant rings, complementary slotted resonant rings, and interdigitated capacitor structures, and the periodic microstructure unit array is arranged in the central axis region of the waveguide structure along the electromagnetic wave propagation direction.

[0035] In this embodiment, taking the complementary slotted resonator ring (SSR unit) as an example, each SRR unit consists of two concentric metal rings with openings in opposite positions. The overall size of the SRR unit can be 1.5mm x 1.5mm, the linewidth of the metal rings is 0.1mm, the ring spacing is 0.1mm, and the opening width is 0.1mm. This SRR array is periodically arranged along the central axis of the waveguide (i.e., the region with the strongest electric field in the quasi-TE10 mode), and its period can be set to 2.0mm.

[0036] Its working principle is as follows: The SRR is an artificial magnetic resonant structure. When the electric field component of an external electromagnetic field (in this case, the main electric field of the quasi-TE10 mode of the SIW) is perpendicular to the SRR plane, it excites an equivalent electric dipole resonance on it. Near the resonant frequency, the SRR unit exhibits a very strong equivalent dielectric constant response, producing a strong capacitive loading effect on the equivalent transmission line of the SIW. Compared to non-resonant grooves, the resonant characteristics of the SRR enable it to produce a much stronger slow-wave effect at specific, designable frequency points.

[0037] Furthermore, the periodic microstructure unit array in this embodiment adopts a non-uniform period, also known as a chirped periodic arrangement, to achieve broadband slow wave characteristics.

[0038] The core feature of this embodiment is that the period of the microstructure unit array is no longer a fixed value, but gradually changes along the Z-axis of the wave propagation direction. The array period increases linearly from the input end to the output end.

[0039] Its working principle is as follows: A slow-wave structure with a fixed period typically exhibits its strongest slow-wave effect within a relatively narrow frequency range. However, by employing a chirped period, different segments of the array generate the strongest coupling and slow-wave effect on electromagnetic waves of different frequencies. For example, segments with shorter periods have a greater impact on higher-frequency waves, while segments with longer periods have a greater impact on lower-frequency waves. When electromagnetic waves sweep through the entire structure, the slow-wave responses of these different segments are spliced ​​and fused together. The macroscopic effect is that, although the peak slow-wave coefficient may decrease slightly, the effective operating bandwidth for achieving the slow-wave effect is significantly broadened.

[0040] Example 2 like Figure 1 As shown in the figure, this embodiment discloses a design method for a substrate-integrated slow waveguide structure, which includes the following steps: S100. Determine the initial size parameters of the waveguide structure based on the preset operating center frequency, bandwidth, and target slow wave coefficient; S200. Establish a parameterized electromagnetic model of the periodic microstructure unit and quantitatively characterize its resonance characteristics and coupling strength; S300. Based on the quantitative characterization, construct a global transmission response model for the periodic microstructure unit array; S400. An optimization algorithm is used to adjust the geometric parameters of the parameterized electromagnetic model and the array arrangement so that the performance of the global transmission response model within the preset operating frequency band meets the design requirements.

[0041] Step S100 is the design start stage, where the performance indicators that the final device needs to achieve are first clarified.

[0042] The design objectives are assumed to be: an operating frequency band of 10.2 GHz to 10.8 GHz; a target slow wave coefficient of no less than 3.0 at the center frequency of 10.5 GHz to achieve significant miniaturization; and return loss better than 15 dB across the entire operating frequency band (i.e., ...). Based on the SIW structure described in Example 1, which consists of upper and lower metal layers and a dielectric substrate, the microstructure unit is a slotted resonant ring.

[0043] In step S200, a parametric 3D model of the SRR element is first established in the electromagnetic simulation software. Its key geometric parameters (i.e., subsequent optimization variables) include: the outer ring radius, ring width, ring spacing, and opening width of the SRR. Next, the response of a single element at different frequencies is extracted through simulation. Then, these simulation data are curve-fitted with the defined Lorentz resonance model function. Through this fitting process, the complex geometric model is abstracted into several key performance parameters: coupling coefficient K, resonant angular frequency, etc. and loaded quality factor The completion of this step means that we have obtained a mathematical surrogate model that can quickly and accurately predict the SRR electromagnetic response, laying the foundation for subsequent efficient global optimization.

[0044] Specifically, the steps for quantitatively characterizing the periodic microstructure unit are as follows: The microstructure unit can be equivalently represented as a two-port network connected in parallel on a transmission line, with its susceptance... Determined by the following formula:

[0045] in, The operating angular frequency; For microstructure units at angular frequency Complex susceptance below; The imaginary unit; The static background susceptance of the non-resonant part is related to the non-resonant capacitance / inductance of the unit cell; is the coupling coefficient, which characterizes the strength of the coupling between the microstructure unit and the main mode field of the transmission line; The natural resonant angular frequency of the unit; The loaded quality factor of the unit reflects the sharpness and loss of the resonance.

[0046] This step equates the physical behavior of complex microstructure units to a lumped-parameter circuit model, which precisely describes the frequency response characteristics of a resonator. This model can accurately predict the susceptance (i.e., the reactance added to the transmission line) of microstructure units at different frequencies, thereby quantifying their ability to alter the phase of electromagnetic waves.

[0047] This function allows designers to quickly evaluate different geometric parameters (these parameters are implicit in...) without performing extensive and time-consuming full-wave electromagnetic simulations. , , The contribution of the Chinese (Chinese) to the slow wave effect greatly improves design efficiency and physical intuition.

[0048] In step S300, after obtaining the accurate mathematical model of a single SRR unit, it is no longer necessary to perform a time-consuming full-wave simulation of the entire waveguide structure containing dozens of SRRs. Instead, we use the more efficient transfer matrix method to construct the global response model.

[0049] Specifically, each SRR unit and the transmission lines between it are considered as a two-port network, and its ABCD transmission matrix can be obtained from the susceptance obtained in step S200. The calculation shows that by concatenating and multiplying the ABCD matrices of all elements, the overall ABCD matrix of the entire SRR array can be calculated instantaneously, and the global transmission response of the entire structure, including the reflection coefficient, can be analytically obtained from this. and phase velocity .

[0050] In step S400, the optimization algorithm solves the following multi-objective weighted integral cost function. To achieve this, use the minimum value:

[0051] in, This is a vector containing all the geometric parameters to be optimized, such as the size and period of the microstructure unit. For about the parameter vector The cost function value; Preset operating angular frequency range; The speed of light in a vacuum; For angular frequency and parameters The phase velocity of electromagnetic waves under these conditions; The target slow wave coefficient; It is a frequency domain weighting function; The input port reflection coefficient of the waveguide structure; The weighting factors for the two optimization objectives are used to adjust the relative importance of the slow wave effect and the matching performance.

[0052] This step constructs a comprehensive cost function. The first term is a weighted integral of the slow wave coefficient error, used to penalize deviations of the actual slow wave coefficients from the target value. Design; The first term is a weighting function that allows setting different optimization weights at different frequency points within the band. The second term is the integral of the square of the magnitude of the reflection coefficient, used to penalize reflection loss within the band and ensure good impedance matching; the goal of optimization algorithms (such as gradient descent and particle swarm optimization) is to find a set of geometric parameter vectors. This makes the total cost function The goal is to achieve a global minimum. This integral form ensures that the optimization objective is the average optimum across the entire operating frequency band, rather than satisfying the requirement only at a few frequency points.

[0053] This method transforms a complex multi-objective optimization problem into a clear mathematical optimization problem, which can automatically balance the contradiction between the slow wave coefficient and impedance matching, and obtain the design scheme with the best overall performance in the entire operating frequency band, avoiding the blindness of manual tuning and the trap of local optima.

[0054] Example 3 In this embodiment, the frequency domain weighting function The mathematical formula for is the Gaussian weighted function, and the mathematical formula for the Gaussian weighted function is:

[0055] in, The center angular frequency of the operating frequency band is defined as follows: ; It is a natural exponential function. The standard deviation of the Gaussian function controls the degree of "focus" in the weighting. The smaller the value, the more concentrated the weight is at the center frequency, forming a sharp peak. The larger the value, the more evenly the weight distribution, approaching uniform weighting.

[0056] The function in this embodiment is applicable to most communication systems because the energy and information of the signal are mainly concentrated near the center frequency of the channel. Using Gaussian weighting allows the optimization algorithm to prioritize the center frequency. The slow wave coefficient at the center frequency is closest to the target value, while the further away from the center frequency, the greater the tolerance error.

[0057] Example 4 In this embodiment, the frequency domain weighting function The mathematical formula for it is the inverse-Byshev weighted function, and the mathematical formula for the inverse-Byshev weighted function is:

[0058] in, This is a Chebyshev polynomial of the first kind, order n, whose characteristic is that it is valid in the interval [missing information]. It oscillates within the interval but grows rapidly outside the interval. This embodiment utilizes its characteristic of reaching its maximum value at the endpoints (-1 and 1) of the interval; n is the order of the polynomial. This is a normal number used to control the relative difference between the center and edge weights. The larger the value, the higher the weight of the edge relative to the center. For the fractional expression, this is a normalization operation that adjusts the operating frequency band. Linear mapping to the standard domain of Chebyshev polynomials superior.

[0059] This embodiment of the function is well-suited for high-performance filter designs or device designs requiring precise bandwidth control. In these applications, parameters such as group delay and reflection loss at the passband edge are often design challenges and critical points. By applying higher weights to the passband edges, the optimization algorithm can be forced to focus on addressing the performance degradation at the passband edges, thereby achieving steeper cutoff characteristics and better passband edge performance.

[0060] Example 5 In this embodiment, the frequency domain weighting function The mathematical formula for this is a piecewise higher-order polynomial weighted function. The mathematical formula for the piecewise higher-order polynomial weighted function is:

[0061]

[0062]

[0063] in, and For two in the total operating frequency band Angular frequency value within; Let be the highest power in the polynomial expansion of the central interval, and be a non-negative integer. In polynomials The multiplication coefficient of the term; Let be the highest order of the polynomial in the marginal interval; In polynomials The multiplication coefficients of the terms. By setting... as well as It can construct weighted curves of any desired shape.

[0064] The function in this embodiment is suitable for special applications with extremely complex design specifications. For example, a multi-functional RF front-end device may require a passband center region (by...) and (Definition) It guarantees extremely low phase distortion (corresponding to a flat slow-wave coefficient) while achieving a specific dispersion compensation slope in the region near the band edge. Through piecewise functions, independent and fine-grained weighted control can be performed on targets in different sub-intervals.

[0065] Example 6 Please refer to Figure 2 This illustration shows a schematic diagram of the structure of a computer device provided by some embodiments of this application. The electronic device 20 includes: a processor 200, a memory 201, a bus 202, and a communication interface 203. The processor 200, the communication interface 203, and the memory 201 are connected via the bus 202. The memory 201 stores a computer program that can run on the processor 200. The processor 200 is used to operate according to the instructions to execute the steps of the method described in any one of embodiments 2-5.

[0066] The memory 201 may include high-speed random access memory (RAM) or non-volatile memory, such as at least one disk storage device. Communication between this system network element and at least one other network element is achieved through at least one communication interface 203 (which can be wired or wireless), such as the Internet, wide area network, local area network, or metropolitan area network.

[0067] Bus 202 can be an ISA bus, PCI bus, or EISA bus, etc. The bus can be divided into address bus, data bus, control bus, etc. Memory 201 is used to store programs. After receiving an execution instruction, processor 200 executes the program. The design method of the substrate-integrated slow waveguide structure disclosed in any of the foregoing embodiments of this application can be applied to processor 200, or implemented by processor 200.

[0068] The processor 200 may be an integrated circuit chip with signal processing capabilities. In implementation, each step of the above method can be completed by the integrated logic circuitry in the hardware of the processor 200 or by instructions in software form. The processor 200 may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it may also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), an off-the-shelf programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this application. The general-purpose processor may be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this application can be directly embodied in the execution of a hardware decoding processor, or executed by a combination of hardware and software modules in the decoding processor. The software modules may reside in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. The storage medium is located in memory 201. The processor 200 reads the information in memory 201 and, in conjunction with its hardware, completes the steps of the above method.

[0069] Example 7 This embodiment also provides a computer-readable storage medium corresponding to the design method of the substrate-integrated slow waveguide structure provided in the foregoing embodiments. Please refer to [link / reference]. Figure 3The computer-readable storage medium shown is an optical disc, on which a computer program (i.e., program product 30) is stored. When the computer program is run by a processor, it executes the design method of the substrate integrated slow waveguide structure provided in any of the foregoing embodiments.

[0070] It should be noted that examples of the computer-readable storage medium may also include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other optical and magnetic storage media, which will not be elaborated here.

[0071] The computer-readable storage medium provided in the above embodiments of this application and the design method of the substrate integrated slow wave waveguide structure provided in the embodiments of this application are based on the same application concept and have the same beneficial effects as the methods adopted, run or implemented by the application programs stored therein.

[0072] It should be noted that in the above text, 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 one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0073] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal (which may be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0074] In summary, the substrate-integrated slow-wave waveguide structure of this invention achieves efficient electromagnetic field coupling and slow-wave effects by setting a periodic microstructure unit array on the inner surface of the upper or lower metal layer. This structure utilizes the coupling between the quasi-TE10 mode electromagnetic field in the waveguide and the microstructure to effectively control the phase velocity of electromagnetic waves, significantly slow down electromagnetic wave transmission, and improve the energy concentration and control capability within the preset operating frequency band. This design features simple manufacturing process, flexible adjustment, and superior performance, greatly satisfying the requirements of high-frequency integrated circuits for high-speed, low-loss, and high-sensitivity signal transmission.

[0075] The design method, computer device, and storage medium of this invention decompose complex design problems into a series of logically clear and executable steps, such as model building, global response prediction, and automated optimization. Combined with mathematical tools, it can efficiently and accurately complete the design of challenging slow waveguide structures. Compared with the traditional "tug-of-war" design method that relies on engineers' experience and repeated trial and error, it has significant efficiency and performance advantages.

[0076] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A substrate-integrated slow-wave waveguide structure, comprising an upper metal layer, a lower metal layer, a dielectric substrate disposed between the upper and lower metal layers, and two rows of metallized vias penetrating the dielectric substrate and connecting the upper and lower metal layers; characterized in that, A periodic microstructure unit array is provided on the inner surface of the upper metal layer and / or lower metal layer facing the dielectric substrate. The periodic microstructure unit array is used to couple with the quasi-TE10 mode electromagnetic field transmitted in the waveguide structure to generate a slow wave effect, thereby reducing the phase velocity of the electromagnetic wave within a preset operating frequency band.

2. The substrate-integrated slow waveguide structure according to claim 1, characterized in that, The periodic microstructure unit is at least one or a combination of grooves, ridges, slotted resonant rings, complementary slotted resonant rings, and interdigitated capacitor structures.

3. A substrate-integrated slow waveguide structure according to claim 1 or 2, characterized in that, The periodic microstructure unit array is arranged along the electromagnetic wave propagation direction in the central axis region of the waveguide structure.

4. The substrate-integrated slow waveguide structure according to claim 1, characterized in that, The period of the periodic microstructure unit array is a non-uniform period or a chirped period.

5. A design method for a substrate-integrated slow waveguide structure as described in any one of claims 1 to 4, characterized in that, Includes the following steps: S100. Determine the initial size parameters of the waveguide structure based on the preset operating center frequency, bandwidth, and target slow wave coefficient; S200. Establish a parameterized electromagnetic model of the periodic microstructure unit and quantitatively characterize its resonance characteristics and coupling strength; S300. Based on the quantitative characterization, construct a global transmission response model for the periodic microstructure unit array; S400. An optimization algorithm is used to adjust the geometric parameters of the parameterized electromagnetic model and the array arrangement so that the performance of the global transmission response model within the preset operating frequency band meets the design requirements.

6. The design method for a substrate-integrated slow waveguide structure according to claim 5, characterized in that, In step S200, the step of quantitatively characterizing the periodic microstructure unit is as follows: The microstructure unit can be equivalently represented as a two-port network connected in parallel on a transmission line, with its susceptance... Determined by the following formula: in, The operating angular frequency; For microstructure units at angular frequency Complex susceptance below; The imaginary unit; The static background susceptance for the non-resonant portion; The coupling coefficient; The natural resonant angular frequency of the unit; The loaded quality factor of the unit.

7. The design method for a substrate-integrated slow waveguide structure according to claim 5, characterized in that, In step S400, the optimization algorithm solves the following multi-objective weighted integral cost function. To achieve this, use the minimum value: in, This is a vector containing all the geometric parameters to be optimized; For about the parameter vector The cost function value; Preset operating angular frequency range; The speed of light in a vacuum; For angular frequency and parameters The phase velocity of electromagnetic waves under these conditions; The target slow wave coefficient; It is a frequency domain weighting function; The input port reflection coefficient of the waveguide structure; These are the weighting factors for the two optimization objectives.

8. The design method for a substrate-integrated slow waveguide structure according to claim 7, characterized in that, The frequency domain weighting function The mathematical formula is one of the following: Gaussian weighted function, inverse Chebyshev weighted function, or piecewise higher-order polynomial weighted function; The mathematical formula for the Gaussian weighted function is: in, The center angular frequency of the operating frequency band is defined as follows: ; It is a natural exponential function. The standard deviation of the Gaussian function; The mathematical formula for the inverse Chebyshev weighted function is: in, Let n be a Chebyshev polynomial of the first kind; n is the order of the polynomial. It is a positive integer; It is a fractional expression; The mathematical formula for the piecewise higher-order polynomial weighted function is: in, and For two in the total operating frequency band Angular frequency value within; Let be the highest power in the polynomial expansion of the central interval, and be a non-negative integer. In polynomials The multiplication coefficient of the term; Let be the highest order of the polynomial in the marginal interval; In polynomials The multiplication coefficient of the term.

9. An electronic device, characterized in that, The system includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the design method for a substrate-integrated slow waveguide structure as described in any one of claims 5-8.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, The program is executed by a processor to implement the design method for a substrate-integrated slow waveguide structure as described in any one of claims 5-8.

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