A design method for a dielectric waveguide filter, a dielectric waveguide filter, a system, a terminal, and a dielectric

Abstract

The present application discloses a design method for a dielectric waveguide filter, a dielectric waveguide filter, a system, a terminal, and a dielectric. The design method for the dielectric waveguide filter includes: introducing a blind hole structure into a four-corner element filter to form a five-corner element filter, wherein the blind hole structure is used to generate additional transmission zeros; performing admittance parameter analysis on the five-corner element filter to obtain parameter information of the five-corner element filter; constructing a polynomial according to the parameter information, and obtaining a coupling matrix according to the polynomial; obtaining a target design according to the coupling matrix, and obtaining a dielectric waveguide filter according to the target design. By regarding the blind hole as a resonator, the present application avoids the use of a negative coupling structure and reduces the occurrence of cross coupling, thereby simplifying the filter design and processing difficulty.

Description

Technical Field

[0001] This application relates to the technical fields of filters and microwave communication, and particularly relates to a design method for a dielectric waveguide filter, a dielectric waveguide filter, a system, a terminal, and a dielectric. Background Art

[0002] In recent years, achieving more transmission zeros under the condition of a simple topological structure to improve the sideband roll-off and out-of-band rejection of microwave filters has become a research hotspot. Recently, an improved generalized Chebyshev function has been used for microwave filter synthesis. This method can achieve a linear topological structure and generate multiple transmission zeros at both ends of the passband. However, there is currently no comprehensive and design method for generating more transmission zeros in a dielectric waveguide filter under simple topological conditions. Moreover, in the filter design process, a negative coupling structure is usually necessary. However, the negative coupling structure will significantly increase the complexity of filter design and the processing cost.

[0003] Therefore, the prior art still needs to be improved and developed. Summary of the Invention

[0004] The main purpose of this application is to provide a design method for a dielectric waveguide filter, a dielectric waveguide filter, a system, a terminal, and a dielectric, aiming to solve the problems of negative coupling and cross-coupling that occur in the design of dielectric waveguide filters in the prior art.

[0005] In the first aspect of the embodiments of this application, a design method for a dielectric waveguide filter is provided. The design method for the dielectric waveguide filter includes the following steps: introducing a blind hole structure into a four-corner element filter to form a five-corner element filter, where the blind hole structure is used to generate additional transmission zeros; analyzing the admittance parameters of the five-corner element filter to obtain the parameter information of the five-corner element filter; constructing a polynomial according to the parameter information, and obtaining a coupling matrix according to the polynomial; obtaining a target design according to the coupling matrix, and obtaining a dielectric waveguide filter according to the target design.

[0006] Optionally, in an embodiment of this application, the five-corner element filter includes a first structure and a second structure; the analyzing the admittance parameters of the five-corner element filter to obtain the parameter information of the five-corner element filter specifically includes: establishing an expression for the admittance parameters of the first structure and an expression for the admittance parameters of the second structure; determining the residues and poles corresponding to the two expressions respectively, where the residues of the two expressions satisfy a preset relationship; extracting the parameter information of the five-corner element filter according to the residues and poles corresponding to the two expressions respectively.

[0007] Optionally, in an embodiment of this application, the expression for the admittance parameters of the first structure is:

[0008] ;

[0009] The expression of the admittance parameter of the second structure is:

[0010] ;

[0011] The preset relationship is:

[0012] , , ;

[0013] Wherein, is the admittance parameter of the first structure, is the imaginary unit, is a constant, is the complex frequency variable, and represent the poles of the first structure, and are the residues corresponding to and respectively; is the admittance parameter of the second structure, represents the pole of the second structure, is the residue corresponding to .

[0014] Optionally, in an embodiment of the present application, the parameter information includes the transmission zero position and the complex reflection zero position, and the polynomial includes a first polynomial, a second polynomial, and a third polynomial; the constructing the polynomial according to the parameter information specifically includes: constructing the first polynomial according to the transmission zero position, and constructing the second polynomial according to the complex reflection zero position; obtaining the third polynomial according to the first polynomial and the second polynomial.

[0015] Optionally, in an embodiment of the present application, the obtaining the coupling matrix according to the polynomial specifically includes: constructing an admittance matrix according to the first polynomial, the second polynomial, and the third polynomial; expanding the admittance matrix into a fractional form related to each node of the filter and the source and the load; obtaining the coupling coefficients according to the fractional form, and obtaining the coupling matrix according to the coupling coefficients.

[0016] Optionally, in an embodiment of the present application, the blind hole structure serves as a resonator with resonance below the passband; the target design includes the positions and dimensions of each resonator; obtaining the target design according to the coupling matrix and obtaining the dielectric waveguide filter according to the target design specifically includes: determining the positions and dimensions of each resonator according to the coupling matrix and designing the dielectric waveguide filter according to the positions and dimensions of each resonator.

[0017] A second aspect of the embodiments of the present application further provides a dielectric waveguide filter, where the dielectric waveguide filter is designed according to the dielectric waveguide filter design method described in any one of the above solutions.

[0018] A third aspect of the embodiments of the present application further provides a dielectric waveguide filter design system, where the dielectric waveguide filter design system is applied to the dielectric waveguide filter design method described in any one of the above solutions, and the dielectric waveguide filter design system includes:

[0019] A blind hole introduction module, configured to introduce a blind hole structure into a four-corner element filter to form a five-corner element filter, where the blind hole structure is used to generate additional transmission zeros;

[0020] An admittance parameter analysis module, configured to perform admittance parameter analysis on the five-corner element filter to obtain parameter information of the five-corner element filter;

[0021] A coupling matrix solving module, configured to construct a polynomial according to the parameter information and obtain a coupling matrix according to the polynomial;

[0022] A waveguide design module, configured to obtain a target design according to the coupling matrix and obtain a dielectric waveguide filter according to the target design.

[0023] A fourth aspect of the embodiments of the present application further provides a terminal, where the terminal includes: a memory, a processor, and a dielectric waveguide filter design program stored on the memory and executable on the processor, and when the dielectric waveguide filter design program is executed by the processor, the steps of the dielectric waveguide filter design method described above are implemented.

[0024] A fifth aspect of the embodiments of the present application further provides a computer-readable storage medium, where the computer-readable storage medium stores a dielectric waveguide filter design program, and when the dielectric waveguide filter design program is executed by a processor, the steps of the dielectric waveguide filter design method described above are implemented.

[0025] Beneficial effects: The present application provides a design method for a dielectric waveguide filter, a dielectric waveguide filter, a system, a terminal, and a medium. By regarding blind holes as resonators, the present application avoids the use of negative coupling structures and reduces the occurrence of cross-coupling, thereby simplifying the filter design and processing difficulty. Moreover, on the basis that the original four-corner element generates two finite transmission zeros, an additional finite transmission zero at an arbitrary position is generated, improving key indicators such as the sideband roll-off and stopband suppression of the dielectric waveguide filter. Description of the Drawings

[0026] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments recorded in the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0027] Figure 1 is a flowchart of a preferred embodiment of the design method for the dielectric waveguide filter of the present application;

[0028] Figure 2 is a schematic diagram of the topological structure of a traditional four-corner element;

[0029] Figure 3 is a schematic diagram of the topological structure of a five-corner element of the present application;

[0030] Figure 4 is a simplified schematic diagram of the topological structure of a five-corner element of the present application;

[0031] Figure 5 is a waveform diagram of the near-band frequency response of a fourth-order filter of the present application;

[0032] Figure 6 is a waveform diagram of the far-band frequency response of a fourth-order filter of the present application;

[0033] Figure 7 is the coupling matrix of a fourth-order filter of the present application;

[0034] Figure 8 is a schematic diagram of the structure of a fourth-order dielectric waveguide filter of the present application;

[0035] Figure 9 is a schematic diagram of the topological structure of an eighth-order filter of the present application;

[0036] Figure 10 is a waveform diagram of the near-band frequency response of an eighth-order filter of the present application;

[0037] Figure 11 is a waveform diagram of the far-band frequency response of an eighth-order filter of the present application;

[0038] Figure 12 It is a schematic structural diagram of the eight - order dielectric waveguide filter of this application;

[0039] Figure 13 It is a schematic diagram comparing the simulation and synthesis results of the eight - order dielectric waveguide filter of this application;

[0040] Figure 14 It is the S - parameter test result of the eight - order dielectric waveguide filter of this application;

[0041] Figure 15 It is the structural diagram of the preferred embodiment of the dielectric waveguide filter design system of this application;

[0042] Figure 16 It is the structural diagram of the preferred embodiment of the terminal of this application.

[0043] Explanation of reference numerals:

[0044] 100, blind - hole introduction module; 200, admittance parameter analysis module; 300, coupling matrix solving module; 400, waveguide design module. Detailed implementation manners

[0045] To make the purpose, technical solutions and effects of this application clearer and more definite, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of this application. The described embodiments are only possible technical implementations of this application, not all possible implementations. Based on the embodiments in this application, those skilled in the art can completely combine the embodiments of this application and obtain other embodiments without creative work, and these embodiments are also within the protection scope of this application.

[0046] First, introduce the nouns involved in the embodiments of this application:

[0047] Quad - element: Refers to a filter element with a specific structure, and its structure includes four main resonant units or coupling structures; the quad - element can be transformed into a penta - element by introducing a blind - hole structure.

[0048] Penta - element: Refers to an element formed by adding a new structural element (such as a blind - hole) on the basis of the quad - element and having five main parts or characteristics; the introduction of the penta - element is to achieve negative coupling and allow the generation of additional transmission zeros in the filter design.

[0049] Negative coupling: Refers to the coupling effect between two resonant units in a microwave or RF filter, which causes the resonant frequencies of them to shift, and the direction of the shift is opposite to that of positive coupling; negative coupling is usually achieved through a specific structure (such as a blind - hole) and affects the frequency response and transmission characteristics of the filter.

[0050] Blind via structure: It refers to a hole drilled in a dielectric substrate that does not penetrate the entire substrate. In microwave or RF filters, blind vias can be used as resonators or to achieve specific coupling effects; the blind via structure serves as a key element for realizing negative coupling in pentagonal elements and resonates below the passband, thus affecting the performance of the filter.

[0051] Resonance: It refers to the resonance phenomenon that occurs in a physical system at a specific frequency. In microwave or RF filters, resonance usually refers to the energy storage and release of a resonant unit (such as a resonator) at a specific frequency; resonance is the basis of filter design, and the frequency and coupling effect of the resonator jointly determine the frequency response of the filter.

[0052] Resonator: It refers to a physical structure that can store and release electromagnetic energy. In microwave or RF filters, resonators are usually key elements for realizing the filtering function; resonators can be part of a quadrilateral element or a pentagonal element, and their performance directly affects the overall performance of the filter.

[0053] Filter: It is a circuit element that can allow signals within a specific frequency range to pass through while suppressing signals in other frequency ranges; the filter is the ultimate goal of the application of terms such as quadrilateral elements, pentagonal elements, resonators, and blind via structures, and these elements jointly determine the frequency response, transmission characteristics, and other performance indicators of the filter.

[0054] The following describes the design method of a dielectric waveguide filter, a dielectric waveguide filter, a system, a terminal, and a medium according to an embodiment of the present application with reference to the accompanying drawings. Regarding the problems of negative coupling and cross-coupling that occur during the design of dielectric waveguide filters in the related technologies mentioned above, the present application provides a design method for a dielectric waveguide filter. In this method, by treating blind vias as resonators, the use of negative coupling structures is avoided, and the occurrence of cross-coupling is reduced, thereby simplifying the filter design and processing difficulty. Moreover, on the basis of generating two finite transmission zeros in the original quadrilateral elements, an additional finite transmission zero at an arbitrary position is generated, improving key indicators such as the sideband roll-off and stopband suppression of the dielectric waveguide filter. Thus, the technical problems of negative coupling and cross-coupling that occur during the design of dielectric waveguide filters in the related technologies are solved.

[0055] It should be noted that finite transmission zeros can significantly improve the frequency selection characteristics of microwave filters. Using out-of-band reflection zeros for filter synthesis and design can avoid the emergence of negative coupling structures and bring more degrees of freedom for filter synthesis and design. In view of the problems existing in the synthesis and design process of dielectric waveguide filters, in order to solve the problems of negative coupling and cross-coupling that occur in the design of existing dielectric waveguide filters and further improve the frequency selection characteristics of the filters, in this application, the blind hole structure in the four-corner element is used as an out-of-band resonator, and the complex reflection zero synthesis method can avoid the occurrence of cross-coupling and negative coupling, significantly reduce the difficulty of filter design and processing, and generate an additional transmission zero.

[0056] In this application, the blind hole structure in the four-corner element is regarded as a resonator resonating below the passband instead of simply as a negative coupling implementation structure for the design of dielectric waveguide filters. The coupling matrix is obtained through the out-of-band complex reflection zero synthesis method to guide the design of dielectric waveguide filters. It has the following advantages: First, an additional finite transmission zero can be generated at any position, effectively improving the near-band frequency selection characteristics of the filter; Second, by adjusting the position of the complex reflection zero, the signs of all coupling coefficients can be made positive and the occurrence of cross-coupling can be avoided, reducing the design and processing difficulty and the interference of parasitic coupling on the filter response; Third, the resonant frequency of the blind hole below the passband can be flexibly controlled, providing more degrees of freedom for filter synthesis and design to adapt to different actual scenarios. Compared with the traditional dielectric waveguide filter design method, this application can achieve better sideband roll-off and stopband suppression without increasing the filter size. Design examples of a fourth-order three-transmission-zero dielectric waveguide filter and an eighth-order six-transmission-zero dielectric waveguide filter are given to prove the effectiveness of the design method proposed by the present invention.

[0057] The technical solutions of this application will be described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments.

[0058] The dielectric waveguide filter design method described in the preferred embodiment of this application, as Figure 1 shown, the dielectric waveguide filter design method includes the following steps:

[0059] In step S101, a blind hole structure is introduced into the four-corner element filter to form a five-corner element filter, wherein the blind hole structure is used to generate an additional transmission zero.

[0060] Specifically, as Figure 2 shown, in the classical four-corner element, the blind hole, which is the implementation structure of negative coupling, is regarded as a resonator resonating below the passband, Figure 2where S represents the source and L represents the load. At this time, the four-corner element is converted into a five-corner element as shown in Figure 3 as shown.

[0061] It can be understood that in the design of a classical four-corner element filter, a negative coupling structure is usually not included. However, in order to generate additional transmission zeros (which can be located anywhere outside the passband of the filter and are used to improve the performance of the filter, such as increasing the out-of-band rejection), negative coupling needs to be introduced. In this application, the negative coupling is achieved by regarding the blind via structure as a resonator that resonates below the passband. A four-corner element refers to a filter structure with four resonators (or equivalent circuit elements). When the blind via structure is introduced, due to its special electromagnetic characteristics, this structure can be regarded as an additional resonator, thus transforming the original four-corner element filter into a five-corner element filter.

[0062] In this application, the introduction of the blind via structure (used as an additional resonator that resonates below the passband) realizes the negative coupling in the filter. Negative coupling is the key to generating additional transmission zeros, which can improve the out-of-band rejection performance of the filter; the transformation from a four-corner element to a five-corner element provides more design freedoms, enabling the performance of the filter to be optimized by adjusting the position and parameters of the blind via structure.

[0063] In step S102, the admittance parameter analysis of the five-corner element filter is performed to obtain the parameter information of the five-corner element filter.

[0064] In a possible implementation manner, the five-corner element filter includes a first structure and a second structure. Establish the expression of the admittance parameter of the first structure and the expression of the admittance parameter of the second structure; determine the residues and poles corresponding to the two expressions respectively, where the residues of the two expressions satisfy a preset relationship; extract the parameter information of the five-corner element filter according to the residues and poles corresponding to the two expressions respectively.

[0065] Specifically, first divide the components. Divide the pentagonal component filter into two parts, and each part has its corresponding admittance parameters, which helps to analyze the characteristics of the filter more clearly; establish the expression of the admittance parameters. For each part, establish the mathematical expression of the admittance parameters according to its circuit structure and component characteristics; determine the residues and poles. In the expression of the admittance parameters, the residue reflects the response intensity of the filter at a specific frequency, while the pole determines the frequency response characteristics of the filter. By analysis and calculation, the specific values of these parameters can be determined; meet specific conditions. To ensure that the filter has the required performance, under the condition of no cross-coupling and all coupling coefficients being positive, specific residues and relationships need to be met; extract the basic parameters. After determining the residues and poles, extract the basic parameters of the filter, such as the positions of the transmission zeros, the positions of the complex reflection zeros, the return loss, and the order, etc. These parameters will be used for subsequent polynomial construction and obtaining the coupling matrix.

[0066] Furthermore, analyze the admittance parameters of the pentagonal component. Divide the pentagonal component into two parts as shown in Figure 4 . The admittance parameters of the first structure are:

[0067] ;

[0068] Among them, is the admittance parameter of the first structure, j is the imaginary unit, r 0 is a constant, is the complex frequency variable, λ 1 and λ 2 represent the poles of the first structure, r 1 and r 2 are the residues corresponding to λ 1 and λ 2 respectively.

[0069] The admittance parameters of the second structure are:

[0070] ;

[0071] Among them, is the admittance parameter of the second structure, λ 3 represents the pole of the second structure, r 3 is the residue corresponding to λ 3.

[0072] If the condition of no cross-coupling and all coupling coefficients being positive in Figure 3 is to be met, then the following conditions (preset relationships) must be satisfied:

[0073] , ;

[0074] By adjusting the positions of a plurality of reflection zeros, the above conditions can be satisfied. Refer to step 103.

[0075] In step S103, a polynomial is constructed according to the parameter information, and a coupling matrix is obtained according to the polynomial.

[0076] In a possible implementation manner, the parameter information includes the positions of transmission zeros and the positions of complex reflection zeros. The polynomial includes a first polynomial, a second polynomial, and a third polynomial. The first polynomial is constructed according to the positions of the transmission zeros, and the second polynomial is constructed according to the positions of the complex reflection zeros; the third polynomial is obtained according to the first polynomial and the second polynomial.

[0077] In a possible implementation manner, an admittance matrix is constructed according to the first polynomial, the second polynomial, and the third polynomial; the admittance matrix is expanded into a fractional form related to each node of the filter and the source and the load; coupling coefficients are obtained according to the fractional form, and a coupling matrix is obtained according to the coupling coefficients.

[0078] In a possible implementation manner, scattering parameters are obtained according to the first polynomial and the second polynomial, and then under the condition that the second polynomial and the third polynomial are known, synthesis of the coupling matrix is performed, and an admittance matrix is constructed according to the scattering parameters.

[0079] Specifically, first, the construction of the polynomial is based on the basic parameters of the filter (such as the positions of transmission zeros, the positions of complex reflection zeros, the return loss RL, and the order) to construct the polynomial. The first polynomial is determined by the positions of the finite transmission zeros, and the second polynomial is composed of complex reflection zeros and pure imaginary reflection zeros, and is divided into 、 two parts; the expression of the scattering parameters uses polynomials to represent the reflection function and the transmission function of the two-port network, and are given in the form of division of polynomials, where the denominator is the third polynomial obtained according to the energy conservation formula. The polynomial expression here is for the subsequent convenient synthesis of the coupling matrix. The synthesis of the coupling matrix is performed under the condition that the polynomials 、 are known, and an admittance matrix and (note that s = jΩ here) are used to construct the admittance matrix . The admittance matrix The expression varies according to the parity of the filter order. Expand the admittance matrix into partial fraction form to establish a connection with the coupling matrix. By comparing the admittance matrices of two different representations, the coupling coefficients between the source and the load can be obtained , as well as the coupling coefficients between the source and the load and the nodes and . By changing the position of the complex reflection zero, the polynomials , and will change. The changes in these polynomials will further affect the magnitudes of the admittance parameters and the coupling matrix values. The position of the complex reflection zero can be determined by a global optimization method to satisfy the residue condition in step S102.

[0080] That is to say, in this application, the scattering parameters are expressed by constructing polynomials, and then the coupling matrix is synthesized. In this process, the position of the complex reflection zero plays a crucial role because it directly affects the form of the polynomial and the value of the coupling matrix. By using a global optimization algorithm to determine the position of the complex reflection zero, the finally designed dielectric waveguide filter can meet specific performance requirements.

[0081] Furthermore, after specifying the basic parameters of the filter, such as the position of the transmission zero, the position of the complex reflection zero, the return loss RL and the order. The corresponding polynomials can be obtained:

[0082] ;

[0083] ;

[0084] where is the first polynomial, Ω is the normalized angular frequency, and the first polynomial P (Ω) is determined by the position of the finite transmission zero Ω TZ，i , is the second polynomial, and the polynomial F (Ω) can be divided into two parts, namely F 2(Ω) formed by the complex reflection zero Ω CRZ，k and F 1(Ω) formed by the pure imaginary reflection zero Ω RZ，j . M , N , Nc represent the number of finite transmission zeros, the number of pure imaginary reflection zeros, and the number of complex reflection zeros respectively.

[0085] For an arbitrary two-port network, its reflection function S 11 and transmission functionS 21 It can be expressed in the form of polynomial division:

[0086] ;

[0087] where 、 are constants related to the return loss RL .

[0088] The third polynomial E (Ω) can be obtained according to the energy conservation formula:

[0089] ;

[0090] Since a passive network is being analyzed, the roots of the polynomial E (Ω) should all be in the left half of the complex plane, and the remaining roots should be discarded. When the number of finite transmission zeros is less than the filter order, ε R = 1; when the number of finite transmission zeros is equal to the filter order, . ε is a constant, defined as:

[0091] ;

[0092] Then, given the above polynomials, the coupling matrix synthesis can be performed. After solving the polynomials F (Ω), E (Ω), the following introduces how to obtain the coupling matrix of the filter using the polynomials. According to the scattering parameters and construct the admittance matrix , where s = jΩ.

[0093] When the filter order is even:

[0094] ;

[0095] When the filter order is odd:

[0096] ;

[0097] where the definitions of the polynomials m and n are:

[0098] ;

[0099] ;

[0100] , are the polynomials , Coefficient of , , are respectively P (Ω), F (Ω), E (Ω) corresponding to the polynomials in the s domain.

[0101] Expand the above formula into partial fraction form (that is, the fraction form related to each node of the filter and the source and load, without expanding the constant term), and the fraction form is expressed as:

[0102] ;

[0103] wherein, represents the admittance matrix, , , and respectively represent the admittance parameters of the two-port network, is the imaginary unit, K represents the coupling coefficient from the source to the load. When the number of transmission zeros is less than the filter order, is zero. When the number of transmission zeros is equal to the filter order, . represents the number of pure imaginary reflection zeros, k is the filter node index, represents the complex frequency variable, represents the eigenvalue of the filter node, , , and respectively represent the residues corresponding to the respective nodes.

[0104] Figure 5 is the transverse topology of the filter, and each resonator is directly coupled to the source and the load. The admittance matrix corresponding to this topology is:

[0105]

[0106] In the formula , represents the coupling coefficient between the source and the load, represents the coupling coefficient between the source and the node, represents the coupling coefficient between the load and the node.

[0107] According to Y the above two different representation methods, we can obtain:

[0108]

[0109] When it is possible to obtain and :

[0110] ;

[0111] and are constants related to the frequency response of the filter nodes respectively.

[0112] For Figure 4 the topology shown in Y the sum of 1 and Y 2 is the admittance parameter Y 12 ( s ) of its corresponding transverse topology. It can be seen that by changing the position of the complex reflection zero, the polynomials P , F and E will change, and then affect the magnitudes of the admittance parameter and the coupling matrix value. Therefore, the position of the complex reflection zero can be determined by a global optimization method to meet the residue condition in step 102.

[0113] In step S104, according to the coupling matrix, the target design of the dielectric waveguide filter is obtained, and the corresponding dielectric waveguide filter is obtained according to the target design.

[0114] In a possible implementation, the blind hole structure serves as a resonator resonating below the passband; the target design includes the positions and sizes of the resonators in the filter. The positions and sizes of the resonators in the dielectric waveguide filter are determined according to the coupling matrix.

[0115] Specifically, the dielectric waveguide filter is designed according to the coupling matrix, and the resonance mode resonating below the passband is realized by the blind hole structure.

[0116] The dielectric waveguide filter design method of the present application has the following advantages:

[0117] First, this application first proposes to regard the blind hole structure as a resonator with resonance below the passband. Through the complex reflection zero synthesis method, the occurrence of negative coupling coefficients and cross-coupling coefficients can be avoided, reducing the influence of parasitic coupling on the response of the dielectric waveguide filter. This simplifies the filter design and processing difficulty. Second, based on the two finite transmission zeros generated by the original four-corner element, this application can generate an additional finite transmission zero at any arbitrary position, greatly improving the key filter indicators such as the sideband roll-off and stopband suppression of the dielectric waveguide filter. Third, this application can flexibly select the position of the complex reflection zero and thereby control the magnitude of the coefficients in the coupling matrix, increasing the degree of freedom in filter synthesis and design and expanding the practical application scope of this method.

[0118] The following further illustrates the above dielectric waveguide filter design method of this application through specific embodiments.

[0119] Embodiment 1:

[0120] This embodiment is a dielectric waveguide filter with fourth-order in-band and three finite transmission zeros and one out-of-band complex reflection zero. The finite transmission zeros are located at -1.5j, -3j, and 2.5j respectively. Figure 2 The figure shows the traditional four-corner element topology structure, where the coupling coefficient between resonator 1 and resonator 4 is negative and needs to be realized using the blind hole structure. Using the design method proposed in this application, first convert the four-corner element in Figure 2 into a five-corner element as shown in Figure 3 . Among them, resonator 4 is realized by the blind hole structure and resonates below the passband. Then, perform the admittance parameter analysis of step 102 on the five-corner element in Figure 3 . Under the condition of a given imaginary part of the complex reflection zero, select an appropriate real part of the complex reflection zero so that all coupling coefficients are positive and there is no cross-coupling between resonator 1 and resonator 5. The simplified five-corner element topology structure is as shown in Figure 4 . In this example, the imaginary parts of the complex reflection zeros are set to -10j, -8.75j, and -5.75j respectively; the corresponding real parts of the complex reflection zeros can be obtained by analyzing the admittance parameters, which are -1.7285, -1.759, and -0.5300 respectively. Figure 5 The figure shows the near-band frequency responses under three different out-of-band complex reflection zero conditions. By comparing the four S 21 parameters (three different complex reflection zeros and one traditional method), the following conclusion can be obtained: Compared with the traditional four-corner element, the design method proposed in this paper can achieve better sideband roll-off characteristics and stopband suppression characteristics without increasing the size. Figure 6 The figure shows the far-band frequency responses under four different conditions. Due to the existence of out-of-band resonance modes, the S of the proposed design method 21The suppression of the parameter at the far end below the passband has a certain degree of decline. Figure 7 Shown is the corresponding coupling matrix when the complex reflection zero is -0.5300 - 5.75j.

[0121] Figure 8 Shown is a schematic diagram of the structural model of a fourth-order dielectric waveguide filter, which includes a feeding port 1, a feeding port 7, resonators 2, 3, 5, and 6 that resonate within the passband, and a resonator 4 (implemented by a blind hole structure) that resonates below the passband.

[0122] In this example, an additional transmission zero is introduced without increasing the size of the dielectric waveguide filter, and the occurrence of negative coupling and cross-coupling is avoided, reducing the design difficulty and processing cost, and greatly improving key performance indicators such as the rectangular coefficient of the dielectric waveguide filter. In addition, the position of the out-of-band complex reflection zero can be arbitrarily adjusted, providing more degrees of freedom for filter synthesis and design, and enabling the solution of the optimal synthesis solution under different scenarios.

[0123] Embodiment 2:

[0124] This embodiment is a dielectric waveguide filter with eight orders in the band and having six finite transmission zeros and two out-of-band complex reflection zeros. The positions of the finite transmission zeros are -2.4j, 1.1j, -3.5j, -1.1j, 2j, and -1.4j respectively. The topological structure is as Figure 9 Shown, where the resonances of resonators 4 and 9 are both implemented by blind hole structures and resonate below the passband. The imaginary part coefficients of the out-of-band complex reflection zeros are respectively set to -7.7339j and -2.4476j. By performing the same admittance parameter analysis method as the above fourth-order filter on this topological structure, the real part coefficients of the two out-of-band complex reflection zeros can be solved, which are 0.3884 and -0.7047 respectively.

[0125] Figure 10 Shown is the near-band frequency response of the eighth-order dielectric waveguide filter. Compared with the eighth-order four-zero dielectric waveguide filter based on the traditional design method, it can be seen that the frequency selection characteristics in the near band are significantly improved due to the increase in the number of transmission zeros. As Figure 11 Shown, at the far end of the passband, due to the existence of complex reflection zeros, the stopband suppression has a slight decline, but it can still be maintained below 60 dB, which will not affect the performance of the filter.

[0126] The schematic diagram of the structural model of the eighth-order dielectric waveguide filter is as Figure 12As shown, where Port 1 and Port 12 are feeding ports, Port 2, 3, 4, 7, 8, 9, and 11 are resonators resonating within the band, and Port 5 and 10 are resonators resonating outside the band, which are realized by the blind via structure. The simulation results in HFSS (High Frequency Structural Simulator) are as Figure 13 shown. Since the filter order is relatively high in this example, the redundant resonance modes outside the band will be suppressed. Therefore, in Figure 13 the frequency response shown, no obvious degradation of the suppression below the passband will be observed, further improving the performance of this method in designing high-order dielectric waveguide filters. Figure 14 The final S-parameter test results verify the effectiveness of the proposed design method for cutoff waveguide filters.

[0127] Compared with the traditional design method for dielectric waveguide filters, this embodiment can achieve additional transmission zeros, greatly improving the frequency selection characteristics of the filter, and the redundant resonance modes below the passband can be effectively suppressed when designing high-order dielectric waveguide filters. This embodiment fully demonstrates the application of the proposed design method in the design of high-order dielectric waveguide filters and shows the cascading method of multiple four-corner elements with out-of-band resonance modes, effectively expanding the application scope of the proposed design method.

[0128] Based on the above embodiments, the present application also provides a dielectric waveguide filter, where the dielectric waveguide filter is designed according to the dielectric waveguide filter design method described in any one of the above solutions.

[0129] Specifically, a fourth-order dielectric waveguide filter and an eighth-order dielectric waveguide filter designed as above.

[0130] Next, a dielectric waveguide filter design system proposed according to an embodiment of the present application will be described with reference to the accompanying drawings.

[0131] Figure 15 is a structural diagram of the dielectric waveguide filter design system according to an embodiment of the present application.

[0132] As Figure 15 shown, the dielectric waveguide filter design system includes: a blind via introduction module 100, an admittance parameter analysis module 200, a coupling matrix solving module 300, and a waveguide design module 400.

[0133] Specifically, the blind via introduction module 100 is used to introduce a blind via structure into the four-corner element filter to form a five-corner element filter, where the blind via structure is used to generate additional transmission zeros;

[0134] The admittance parameter analysis module 200 is configured to perform admittance parameter analysis on the pentagonal element filter to obtain parameter information of the pentagonal element filter;

[0135] The coupling matrix solving module 300 is configured to construct a polynomial according to the parameter information and obtain a coupling matrix according to the polynomial;

[0136] The waveguide design module 400 is configured to obtain a target design according to the coupling matrix and obtain a dielectric waveguide filter according to the target design.

[0137] Figure 16 This is a structural diagram of the terminal provided by the embodiment of the present application. The terminal may include:

[0138] A memory 501, a processor 502, and a computer program stored on the memory 501 and executable on the processor 502.

[0139] When the processor 502 executes the program, it implements the dielectric waveguide filter design method provided in the above embodiment.

[0140] Furthermore, the terminal further includes:

[0141] A communication interface 503 for communication between the memory 501 and the processor 502.

[0142] The memory 501 is used to store a computer program executable on the processor 502.

[0143] The memory 501 may include a high-speed RAM memory and may also include non-volatile memory, such as at least one disk memory.

[0144] If the memory 501, the processor 502, and the communication interface 503 are implemented independently, the communication interface 503, the memory 501, and the processor 502 may be interconnected through a bus and communicate with each other. The bus may be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. The bus may be divided into an address bus, a data bus, a control bus, etc. For the sake of simplicity of representation, Figure 16 only a thick line is shown in the figure, but it does not mean that there is only one bus or one type of bus.

[0145] Optionally, in a specific implementation, if the memory 501, the processor 502, and the communication interface 503 are integrated on a single chip, the memory 501, the processor 502, and the communication interface 503 can communicate with each other through an internal interface.

[0146] The processor 502 may be a central processing unit (CPU for short), or an application specific integrated circuit (ASIC for short), or one or more integrated circuits configured to implement the embodiments of the present application.

[0147] This embodiment also provides a computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, the medium waveguide filter design method as described above is implemented.

[0148] An embodiment of the present application provides a computer program product, including a computer program, and when the computer program is executed by a processor, it implements the medium waveguide filter design method provided in any of the embodiments corresponding to the present application Figure 1 as described in the embodiments.

[0149] In the description of this specification, the descriptions with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or N embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0150] In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "N" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0151] Any process or method description represented in the flowchart or described otherwise herein can be understood to represent a module, segment, or portion of code including one or N executable instructions for implementing a customized logical function or process. The scope of the preferred embodiments of this application includes additional implementations where functions may be executed in a substantially simultaneous manner or in the reverse order according to the functions involved, rather than in the order shown or discussed, which should be understood by those skilled in the technical field of the embodiments of this application.

[0152] The logic and / or steps represented in the flowchart or described otherwise herein, for example, can be considered as a sequenced list of executable instructions for implementing a logical function, and can be specifically implemented in any computer-readable storage medium for use by an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other systems that can fetch and execute instructions from the instruction execution system, apparatus, or device), or in conjunction with these instruction execution systems, apparatuses, or devices. For the purposes of this specification, a "computer-readable storage medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by or in conjunction with an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of the computer-readable storage medium include the following: an electrical connection portion with one or N wirings (electronic device), a portable computer diskette (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable storage medium can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically by optically scanning the paper or other media, followed by editing, interpretation, or otherwise processing as appropriate, and then stored in a computer memory.

[0153] It should be understood that various parts of this application can be implemented using hardware, software, firmware, or combinations thereof. In the above embodiments, the N steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one of the following techniques known in the art or combinations thereof can be used: discrete logic circuits having logic gate circuits for implementing logical functions on data signals, application specific integrated circuits having appropriate combinational logic gate circuits, programmable gate arrays (PGAs), field programmable gate arrays (FPGAs), etc.

[0154] Those of ordinary skill in the art can understand that all or part of the steps carried out in implementing the above-described embodiment methods can be completed by a program instructing relevant hardware. The program can be stored in a computer-readable storage medium, and when executed, it includes one or a combination of the steps of the method embodiment.

[0155] In addition, in each of the embodiments of the present application, the functional units can be integrated into a processing module, or each unit can exist physically alone, or two or more units can be integrated into one module. The above-mentioned integrated module can be implemented in the form of hardware or in the form of a software functional module. When the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0156] The above-mentioned storage medium can be a read-only memory, a magnetic disk, an optical disk, etc. Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

[0157] It should be understood that the application of the present application is not limited to the above examples. For those of ordinary skill in the art, improvements or transformations can be made according to the above description, and all such improvements and transformations should fall within the protection scope of the appended claims of the present application.

[0158] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and are not intended to limit them. Although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features. These modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A dielectric waveguide filter design method, characterized in that: The dielectric waveguide filter design method comprises: Introducing a blind hole structure into a four-corner element filter to form a five-corner element filter, wherein the blind hole structure is used to generate an additional transmission zero point; Performing admittance parameter analysis on the pentagonal element filter to obtain parameter information of the pentagonal element filter; constructing a polynomial according to the parameter information, and obtaining a coupling matrix according to the polynomial; Obtaining a target design according to the coupling matrix, and obtaining a dielectric waveguide filter according to the target design; The pentagonal element filter includes a first structure and a second structure; The step of performing admittance parameter analysis on the pentagonal element filter to obtain parameter information of the pentagonal element filter specifically includes: Establishing an expression for an admittance parameter of the first structure and an expression for an admittance parameter of the second structure; Determine the residues and the extreme points corresponding to the two expressions, respectively, wherein the residues of the two expressions satisfy a preset relationship; Extracting parameter information of the pentagonal element filter according to the residues and poles corresponding to the two expressions; The expression of the admittance parameter of the first structure is: ； The expression of the admittance parameter of the second structure is: ； The preset relationship is: ， ， ； in, is the admittance parameter of the first structure, is an imaginary unit, is a constant, is a complex frequency variable, and represents the poles of the first structure, and Corresponding to and The residue of is the admittance parameter of the second structure, represents the poles of the second structure, To correspond to The residue of The parameter information includes a transmission zero point position and a complex reflection zero point position, and the polynomial includes a first polynomial, a second polynomial and a third polynomial; The constructing of a polynomial according to the parameter information specifically includes: constructing a first polynomial according to the transmission zero point position, and constructing a second polynomial according to the complex reflection zero point position; Obtain a third polynomial according to the first polynomial and the second polynomial; The obtaining of the coupling matrix according to the polynomial specifically includes: constructing an admittance matrix according to the first polynomial, the second polynomial and the third polynomial; Expanding the admittance matrix into a fractional form associated with each node of the filter and the source and load; A coupling coefficient is obtained according to the fractional form, and a coupling matrix is ​​obtained according to the coupling coefficient.

2. The dielectric waveguide filter design method according to claim 1, characterized in that: The blind hole structure acts as a resonator that resonates below the passband; The target design includes the location and size of each resonator; The step of obtaining a target design according to the coupling matrix and obtaining a dielectric waveguide filter according to the target design is specifically as follows: The position and size of each resonator are determined according to the coupling matrix, and a dielectric waveguide filter is designed according to the position and size of each resonator.

3. A dielectric waveguide filter, characterized in that: The dielectric waveguide filter comprises five blind hole structures arranged on a shell; the dielectric waveguide filter is designed according to the dielectric waveguide filter design method according to any one of claims 1 to 2.

4. A dielectric waveguide filter design system, characterized in that: The dielectric waveguide filter design system is applied to the dielectric waveguide filter design method according to any one of claims 1 to 2, and the dielectric waveguide filter design system comprises: A blind hole introduction module, used for introducing a blind hole structure into a four-corner element filter to form a five-corner element filter, wherein the blind hole structure is used to generate an additional transmission zero point; An admittance parameter analysis module, used for performing admittance parameter analysis on the pentagonal element filter to obtain parameter information of the pentagonal element filter; A coupling matrix solving module, used for constructing a polynomial according to the parameter information, and obtaining a coupling matrix according to the polynomial; The waveguide design module is used to obtain a target design according to the coupling matrix, and obtain a dielectric waveguide filter according to the target design.

5. A terminal, characterized in that: The terminal includes: a memory, a processor, and a dielectric waveguide filter design program stored in the memory and executable on the processor, wherein the dielectric waveguide filter design program implements the steps of the dielectric waveguide filter design method according to any one of claims 1 to 2 when executed by the processor.

6. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a dielectric waveguide filter design program, and when the dielectric waveguide filter design program is executed by a processor, the steps of the dielectric waveguide filter design method according to any one of claims 1 to 2 are implemented.

Images