High-isolation dual-band substrate integrated waveguide filter crossing device and working method thereof

Abstract

The invention provides a high-isolation dual-band substrate integrated waveguide filter crossing device and a working method thereof. Comprising a dielectric layer (2), a top metal layer (1) located on the upper surface of the dielectric layer (2), a middle metal layer (3) located in the dielectric layer (2), a bottom metal layer (4) located on the lower surface of the dielectric layer (2), a first metalized through hole array (5), a second metalized through hole array (6) and a third metalized through hole array (7). The first metalized through hole array (5) penetrates through the dielectric layer (2) and is connected with the top metal layer (1), the middle metal layer (3) and the bottom metal layer (4); the second metalized through hole array (6) is connected with the top metal layer (1) and the middle metal layer (3); the third metalized through hole array (7) is connected with the bottom metal layer (4) and the middle metal layer (3); by applying the technical scheme, dual-band filtering response can be realized.

Description

Technical Field

[0001] This invention relates to the field of microwave technology, and in particular to a high-isolation dual-band substrate integrated waveguide filter crossover and its operating method. Background Technology

[0002] Planar crossovers are key components in microwave systems, allowing two signals to cross over without interference. In modern wireless systems, bandpass filters and crossovers are often cascaded, but this cascading increases system size and complexity. To mitigate this, filter crossovers have emerged as a viable solution, integrating multiplexing and frequency selection capabilities. This method effectively reduces cascading losses and system area. Substrate integrated waveguide (SIW) technology, with its low cost, low loss, high power handling capability, and ease of integration, provides an attractive design platform for high-performance and low-cost filter crossover designs.

[0003] Traditional SIW filter crossovers utilize a pair of orthogonal degenerate modes in a square dual-mode cavity to design the crossover, achieving only a single-band filtering response, which is insufficient to meet the growing demands of multi-band communication systems. With the increasing need for multi-band wireless communication technology, multi-band components are indispensable for advanced RF transceivers. Currently, research on SIW dual-band filter crossovers is scarce. Reported SIW dual-band filter crossovers are based on four-mode resonator designs, which are complex and have poor isolation. This invention proposes a simple, high-isolation SIW dual-band filter crossover. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a high-isolation dual-band substrate integrated waveguide filter crossover and its working method, wherein a band-stop resonator is connected in parallel above a bandpass resonator and coupled through a gap to achieve a dual-band filtering response.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a high-isolation dual-band substrate integrated waveguide filter crossover, comprising: a dielectric layer (2), a top metal layer (1) located on the upper surface of the dielectric layer (2), an intermediate metal layer (3) located within the dielectric layer (2), a bottom metal layer (4) located on the lower surface of the dielectric layer (2), a first metallized via array (5), a second metallized via array (6), and a third metallized via array (7); the first metallized via array (5) penetrates the dielectric layer (2) and connects the top metal layer (1), the intermediate metal layer (3), and the bottom metal layer (4); the second metallized via array (6) connects the top metal layer (1) and the intermediate metal layer (3); the third metallized via array (7) connects the bottom metal layer (4) and the intermediate metal layer (3); It also includes a first input port, a first output port, a second input port, and a second output port; the dielectric layer (2), the top metal layer (1), the middle metal layer (3), the bottom metal layer (4), and the first metallized via array (5) constitute two SIW dual-mode resonant cavities and eight SIW single-mode resonant cavities; the SIW dual-mode resonant cavity specifically includes a third SIW mode resonator (10) and an eighth SIW resonator (15); the SIW single-mode resonant cavity specifically includes a first SIW resonator (8), a second SIW resonator (9), a fourth SIW resonator (11), a fifth SIW resonator (12), a sixth SIW resonator (13), a seventh SIW resonator (14), a ninth SIW resonator (16), and a tenth SIW resonator (17); The third SIW mode resonator (10), the eighth SIW resonator (15), the first SIW resonator (8), the second SIW resonator (9), the sixth SIW resonator (13), and the seventh SIW resonator (14) constitute channel one of the filter crossover; the first SIW resonator (8), the third SIW mode resonator (10), and the second SIW resonator (9) are bandpass resonators that constitute a bandpass response; the sixth SIW resonator (13), the eighth SIW resonator (15), and the seventh SIW resonator (14) are bandstop resonators that constitute a bandstop response to split the bandpass response and realize the dual-band response of channel one; The third SIW mode resonator (10), the eighth SIW resonator (15), the fourth SIW resonator (11), the fifth SIW resonator (12), the ninth SIW resonator (16), and the tenth SIW resonator (17) constitute channel two of the filter crossover; the fifth SIW resonator (12), the third SIW mode resonator (10), and the fourth SIW resonator (11) are bandpass resonators that constitute a bandpass response; the tenth SIW resonator (17), the eighth SIW resonator (15), and the ninth SIW resonator (16) are bandstop resonators that constitute a bandstop response to split the bandpass response and realize the dual-band response of channel two.

[0006] In a preferred embodiment, the first SIW resonator (8) and the third SIW resonator (10) share a common sidewall, and the common sidewall has symmetrically arranged first coupling windows; the second SIW resonator (9) and the third SIW resonator (10) share a common sidewall, and the common sidewall has symmetrically arranged second coupling windows; one of the non-common sidewalls of the first SIW resonator (8) has a first input window with a width of W01, and one of the non-common sidewalls of the third SIW resonator (9) also has a first output window with a width of W01; the first coupling window, the second coupling window, the first input window, and the first output window are not provided with a first metallized via array (5), and the third SIW resonator (10), the first SIW resonator (8), and the second SIW resonator (9) are provided with a second metallized via array (6).

[0007] In a preferred embodiment, the sixth SIW resonator (13) and the eighth SIW resonator (15) share a common sidewall, and no coupling window is provided on the common sidewall; the eighth SIW resonator (15) and the seventh SIW resonator (14) share a common sidewall, and no coupling window is provided on the common sidewall; a third metallized via array (7) is provided at the first input window position of the sixth SIW resonator (13), and a third metallized via array (7) is provided at the first output window of the seventh SIW resonator (14); no second metallized via array (6) is provided in the eighth SIW resonator (15), the sixth SIW resonator (13), the seventh SIW resonator (14), the ninth SIW resonator (16), and the tenth SIW resonator (17).

[0008] In a preferred embodiment, the fifth SIW resonator (12) and the third SIW resonator (10) share a common sidewall, and the common sidewall has symmetrically arranged third coupling windows; the fourth SIW resonator (11) and the third SIW resonator (10) share a common sidewall, and the common sidewall has symmetrically arranged fourth coupling windows; one of the non-common sidewalls of the first SIW resonator (12) has a second input window with a width of WO2, and one of the non-common sidewalls of the fourth SIW resonator (11) also has a second output window with a width of WO2; the third coupling window, the fourth coupling window, the second input window, and the second output window are not provided with a first metallized via array (5), and the fourth SIW resonator (11) and the fifth SIW resonator (12) are provided with a second metallized via array (6).

[0009] In a preferred embodiment, the tenth SIW resonator (17) and the eighth SIW resonator (15) share a common sidewall, and no coupling window is provided on the common sidewall; the eighth SIW resonator (15) and the ninth SIW resonator (16) share a common sidewall, and no coupling window is provided on the common sidewall; a third metallized via array (7) is provided at the second input window position of the tenth SIW resonator (17), and a third metallized via array (7) is provided at the second output window of the ninth SIW resonator (16).

[0010] In a preferred embodiment, a first microstrip line is connected to the first input window of the top metal layer (1), and the first microstrip line serves as the input port of filter crossover channel one; a second microstrip line is connected to the first output window of the top metal layer (1), and the second microstrip line serves as the first output port of filter crossover channel one; a third microstrip line is connected to the second input window of the top metal layer (1), and the third microstrip line serves as the input port of filter crossover channel two; a fourth microstrip line is connected to the second output window of the top metal layer (1), and the fourth microstrip line serves as the second output port of filter crossover channel two.

[0011] In a preferred embodiment, the top metal layer (1) has an L-shaped groove on each side of the first microstrip line, the second microstrip line, the third microstrip line, and the fourth microstrip line.

[0012] In a preferred embodiment, the single-mode cavity TE is controlled by adjusting the lengths TSL1 and TSL2 of the L-shaped grooves on both sides of the microstrip line. 101 The power supply strength of the mode.

[0013] In a preferred embodiment, in the intermediate metal layer (1), grooves are formed along the edge of the first metallized via array (5) at the center of the cavities of the sixth SIW resonator (13), the seventh SIW resonator (14), the ninth SIW resonator (16), and the tenth SIW resonator (17), and the grooves are d1 away from the first metallized via array (5); a cross-shaped groove is formed at the center of the cavities of the eighth SIW resonator (15); the grooves in the intermediate metal layer are used to adjust the coupling strength between the upper bandpass resonator and the lower bandstop resonator, so as to achieve the effect of splitting a single frequency band into a dual frequency band.

[0014] This invention also provides a method for operating a high-isolation dual-band substrate integrated waveguide filter crossover, based on the aforementioned high-isolation dual-band substrate integrated waveguide filter crossover; an electromagnetic signal is input from the first microstrip line, and TE is excited in the first SIW resonator (8). 101 mold; Among them, TE 101The mode is coupled to the third SIW resonator (10) through a first symmetrical coupling window with a width of W1, thereby exciting the TE in the third SIW resonator (10). 102 The mode is then coupled to the second SIW resonator (9) through the second symmetrical coupling window with the same width W1; while the first SIW resonator (8), the second SIW resonator (9), and the third SIW mode resonator (10) are coupled to the lower sixth SIW resonator (13), the eighth SIW resonator (15), and the seventh SIW resonator (14) through the slot line along the Y-axis in the intermediate metal layer (3), so as to realize the response of the dual-band filter crossover channel one; The electromagnetic signal is input from the second microstrip line and excites TE in the fifth SIW mode resonator (12). 101 mold; Among them, TE 101 The mode is coupled to the third SIW mode resonator (10) through a third symmetrical coupling window with a width of W2, thereby exciting the TE in the third SIW mode resonator (10). 201 The mode is then coupled to the fourth SIW mode resonator (11) through the fourth symmetrical coupling window with the same width W2; while the third SIW mode resonator (10), the fourth SIW mode resonator (11), and the fifth SIW mode resonator (12) are coupled to the lower ninth SIW resonator (16), the eighth SIW resonator (15), and the tenth SIW resonator (17) through the slot line along the X-axis direction in the intermediate metal layer (3), thereby realizing the response of the second channel of the dual-band filter crossover. TE in the third SIW mode resonator (10) 102 Model and TE 201 The mode is a pair of orthogonal degenerate modes, providing dual-channel isolation; when the third SIW mode resonator (10) operates in mode two, the phases are opposite at the third coupling window and the fourth coupling window, and the energy coupled to the fifth SIW mode resonator (12) and the fourth SIW mode resonator (11) cancels out; similarly, when the third SIW mode resonator (10) operates in mode three, the phases are opposite at the first coupling window and the second coupling window, and the energy coupled to the fifth SIW mode resonator (12) and the fourth SIW mode resonator (11) also cancels out.

[0015] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention achieves dual-band filtering response by using a stacked structure to connect a band-stop resonator in parallel on the basis of a SIW single-band filter crossover; (2) By adding metal pillars to the upper resonant cavity, the dimensions of the upper and lower cavities are consistent, reducing the number of blind holes, thereby reducing the design difficulty and processing cost; (3) The coupling coefficients of the TE102 and TE201 modes in the dual-mode resonator are independently controllable, and the design is simple; (4) The use of a symmetrical coupling window structure around the dual-mode resonant cavity improves the isolation between the two channels of the filter crossover. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of the filter crossover provided in this embodiment; Figure 2 This is a schematic diagram of the top metal layer of the filter crossover provided in this embodiment; Figure 3 The single-mode resonant cavity TE provided in this embodiment 101 TE102 mode and dual-mode resonator; Figure 4 The single-mode resonant cavity TE provided in this embodiment 201 Model electric field amplitude distribution diagram and electric field direction diagram; Figure 5 This is the filter crossover topology diagram provided in this embodiment; Figure 6 This is a curve showing the coupling coefficient of the TE102 and TE201 modules provided in this embodiment as a function of the cross groove lengths SL2 and SL3; Figure 7 This is a curve showing the variation between the width W1 of the symmetrical coupling structure and the bandwidth and isolation in the dual-mode resonator provided in this embodiment; The diagram is labeled as follows: 1. Top metal layer; 2. Dielectric layer; 3. Middle metal layer; 4. Bottom metal layer; 5. First metallized via array; 6. Second metallized via array; 7. Second metallized via array; 8. First SIW resonator; 9. Second SIW resonator; 10. Third SIW mode resonator; 11. Fourth SIW mode resonator; 12. Fifth SIW mode resonator; 13. Sixth SIW resonator; 14. Seventh SIW resonator; 15. Eighth SIW resonator; 16. Ninth SIW resonator; 17. Tenth SIW resonator. Among them, 10 and 15 are dual-mode SIW resonators used as crossover units in a filter crossover circuit, and the rest are single-mode SIW resonators. Detailed Implementation

[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0018] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0019] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations according to this application; as used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise; furthermore, it should be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0020] like Figure 1 As shown, this embodiment provides a high-isolation dual-band filter crossover. The first band of both channels operates around 8.78 GHz, and the second band operates around 9.43 GHz. It utilizes SIW dual-mode cavity degenerate mode TE. 102 Model and TE 201 The orthogonality of the modules and the setting of the symmetric coupling window enable TE 102 Model and TE 201 The phases of the modes cancel each other out at the coupling window of another channel to achieve high isolation. The isolation of both frequency bands is greater than 28dB. The dual frequency bands are achieved by connecting a band group resonator in parallel on the bandpass resonator and coupling through the coupling slot line on the intermediate metal layer to split the frequency band, while maintaining the characteristics of miniaturization and simple design.

[0021] Specifically, it includes: a dielectric layer 2, a top metal layer 1 located on the upper surface of the dielectric layer 2, an intermediate metal layer 3 located within the dielectric layer 2, a bottom metal layer 4 located on the lower surface of the dielectric layer 2, a first metallized via array 5, a second metallized via array 6, a third metallized via array 7, a first input port, a first output port, a second input port, and a second output port.

[0022] For example, dielectric layer 2 is formed by stacking two dielectric substrates. Specifically, the dielectric substrate is a Tanconic TLY-5 dielectric substrate with a relative permittivity of 2.2, a loss tangent of 0.0009, and a thickness of 0.508 mm. The intermediate metal layer 3 is located between the upper and lower dielectric substrates.

[0023] The first metallized via array 5 is composed of multiple periodically distributed first metallized vias, which penetrate the dielectric layer 2 and connect the top metal layer 1, the middle metal layer 3 and the bottom metal layer 4.

[0024] The second metallized via array 6 is composed of a plurality of periodically distributed second metallized vias, which penetrate the upper half of the dielectric substrate of the dielectric layer 2 and connect the top metal layer 1 and the middle metal layer 3.

[0025] The third metallized via array 7 is composed of multiple periodically distributed third metallized vias, which penetrate the lower half of the dielectric substrate of the dielectric layer 2 and connect the bottom metal layer 4 and the intermediate metal layer 3.

[0026] The SIW single-mode resonant cavity and SIW dual-mode resonant cavity are composed of a dielectric layer 2, a top metal layer 1, an intermediate metal layer 3, a bottom metal layer 4, and a first metallized via array 5. The resonant cavity includes a first SIW resonator 8 arranged in a cross shape and connected to the second SIW resonator 9; a third SIW resonator 10; a fourth SIW resonator 11; a fifth SIW resonator 12; a sixth SIW resonator 13; a seventh SIW resonator 14; an eighth SIW resonator 15; a ninth SIW resonator 16; and a tenth SIW resonator 17.

[0027] The first SIW resonator 8 and the third SIW resonator 10 share a common sidewall, and symmetrically arranged first coupling windows are formed on the common sidewall; the second SIW resonator 9 and the third SIW resonator 10 share a common sidewall, and symmetrically arranged second coupling windows are formed on the common sidewall; one of the non-common sidewalls of the first SIW resonator 8 has a first input window with a width of W01, and one of the non-common sidewalls of the third SIW resonator 9 also has a first output window with a width of W01; the first coupling window, the second coupling window, the first input window, and the first output window are not provided with a first metallized via array 5, but the first input window and the first output window are provided with a third metallized via array 7. For example, the first input window and the first output window are located on the same straight line.

[0028] The first and second coupling windows have the same width, W1. Adjusting the width W1 can affect the 666 bandwidth and isolation of the filter crossbar channel one.

[0029] The fifth SIW resonator 12 and the third SIW resonator 10 share a common sidewall, and symmetrically arranged third coupling windows are formed on the common sidewall; the fourth SIW resonator 11 and the third SIW resonator 10 share a common sidewall, and symmetrically arranged fourth coupling windows are formed on the common sidewall; one of the non-common sidewalls of the first SIW resonator 12 has a second input window with a width of W02, and one of the non-common sidewalls of the fourth SIW resonator 11 also has a second output window with a width of W02; the third coupling window, the fourth coupling window, the second input window, and the second output window are not provided with the first metallized via array 5, but the second input window and the second output window are provided with the third metallized via array 7. For example, the second input window and the second output window are also located on the same straight line.

[0030] The third and fourth coupling windows have the same width, W2. Adjusting the width W2 can affect the bandwidth and isolation of the second channel of the filter crossover.

[0031] One implementation method Figure 2 This is a schematic diagram of the parameters of each component in the top metal layer of this embodiment. The top metal layer 1 has a notch with a width of W01 at its first input window position. A first microstrip line is disposed within this notch and is connected to the top metal layer 1. The first microstrip line serves as the first input port of the filter crossover. Preferably, an "L"-shaped slot with a width of TSW1 and lengths of TSL1 and TSL2 is formed on each side of the first microstrip line and is located at the center of the first SIW resonator 8. The top metal layer 1 also has a notch with a width of W01 at its first output window position. A second microstrip line is disposed within this notch and is connected to the top metal layer 1. The second microstrip line serves as the first output port of the filter crossover. Preferably, an "L"-shaped slot with a width of TSW1 and lengths of TSL1 and TSL2 is formed on each side of the first microstrip line and is located at the center of the second SIW resonator 9. The first and second microstrip lines are symmetrically arranged about the Y-axis, thereby controlling the feed strength of the filter crossover channel one input / output.

[0032] The second input window of the top metal layer 1 has a notch with a width of W02. A third microstrip line is housed within this notch and connected to the top metal layer 1. This third microstrip line serves as the second input port of the filter crossover. Preferably, an L-shaped slot with a width of TSW2 and lengths of TSL3 and TSL4 is formed on each side of the third microstrip line and located at the center of the fifth SIW resonator 12. Similarly, the second output window of the top metal layer 1 has a notch with a width of W02. A fourth microstrip line is housed within this notch and connected to the top metal layer 1. This fourth microstrip line serves as the second output port of the filter crossover. Preferably, an L-shaped slot with a width of TSW1 and lengths of TSL1 and TSL2 is formed on each side of the first microstrip line and located at the center of the fourth SIW resonator 11. The third and fourth microstrip lines are symmetrically arranged about the X-axis, thereby controlling the feed strength of the filter crossover channel two input / output.

[0033] As an example, the first resonator 8, the second resonator 9, the third resonator 10, the fourth resonator 11, and the fifth resonator 12 are provided with a second metallized via array 6 at their four corners. The distance between the second metallized via array 6 and the edge of the resonant cavity in the third resonator 10 is S1, and the distance between the second metallized via array 6 and the edge of the resonant cavity in the other resonant cavities is S2. Adjusting S1 and S2 can allocate the bandwidth of the dual-band.

[0034] As an example, the first, second, third, and fourth microstrip lines all have a 50-ohm impedance and a width of MSW.

[0035] One implementation method Figure 3 This is a schematic diagram of the parameters of each component in the intermediate metal layer of this embodiment. The intermediate metal layer 3 has slots of width SW1 and length SL1 at the edge of the common sidewall near the eighth SIW resonator 15 of the sixth SIW resonator 13, seventh SIW resonator 14, ninth SIW resonator 16, and tenth SIW resonator 17. The distance between the slots and the common sidewall is d1. No coupling window is present on the common sidewall. Furthermore, a cross-shaped slot of width SW2 and lengths SL2 and SL3 is formed at the center of the eighth SIW resonator 15. The cross-shaped slot with a length of SL3 along the Y-axis is used for TE. 102 The coupling of the modules, the cross-shaped groove with a length of SL2 in the X-axis direction, is used for TE. 201 Mode coupling. The slots in the intermediate metal layer 3 are used to control the coupling strength between the upper bandpass resonator and the lower bandstop resonator. The stronger the coupling, the wider the intermediate stopband bandwidth of the dual-band system. Resonators 13, 14, 15, 16, and 17 all have a second metallized via array 6.

[0036] The bottom metal layer 4 is located below the dielectric layer 2, and it is a rectangular metal layer of the same size as the dielectric layer 1.

[0037] Table 1. Dimensions of the filter crossover (unit: mm) MSW TSW1 TSL1 TSL2 1.56 0.23 7.28 3.61 W01 TSW2 TSL3 TSL4 2.7 0.23 7.26 3.61 W02 S1 S2 W1 2.7 4.23 4.24 5.78 Wt1 W2 Wt2 SW1 7 5.78 7 0.44 SL1 d1 SW2 SL2 4.34 0.2 0.48 5.67 W L Dv P 24.3 12.75 0.6 1.1 SL3 5.67 Figures 3-4 It is a SIW single-mode resonator TE 101 TE dual-mode resonator of SIW 102 Model, TE 201 The mode electric field amplitude distribution diagram and electric field vector diagram are shown in the figure. As can be seen from the figure, the SIW single-mode resonator TE... 101 TE dual-mode resonator with SIW 102 Model, TE 201 Both modes can be coupled, SIW dual-mode resonator TE 102 Model and TE 201 The modules are orthogonal, and TE 102 Model and TE 201 The modulus itself has opposite phase, in Figure 2 TE in the resonant cavity along the X-axis 101 Through the symmetrical double coupling window on the common sidewall of resonant cavities 8 and 10, and the TE in resonant cavity 10 102 Mode coupling, but at the symmetrical coupling window of resonator 10 along the Y-axis direction, TE 102Since the modes are out of phase and their energies cancel each other out, coupling cannot be achieved through a symmetrical dual coupling window along the Y-axis. Similarly, TE... 201 The modules can only be coupled through a symmetrical dual coupling window along the Y-axis, but not through a symmetrical dual coupling window along the X-axis. This characteristic is used to set up a symmetrical dual coupling window to improve the isolation between the two channels.

[0038] Figure 5 This is the filter crossover topology diagram provided in this embodiment. P1 represents the first input port, P2 represents the second input port, P3 represents the first output port, and P4 represents the second output port. The blue-background resonators constitute channel one, where 1 Ⅰ 3 Ⅰ TE represents a single-mode bandpass resonator 101 Modulus, 2 Ⅰ TE represents a dual-mode bandpass resonator 102 Modulus, 1 Ⅱ 3 Ⅱ TE represents a single-mode band-stop resonator 101 Modulus, 2 Ⅱ TE represents a single-mode bandpass resonator 102 The mode, with orange-patterned resonators forming channel two, of which 1 Ⅰ 3 Ⅰ TE represents a single-mode bandpass resonator 101 Modulus, 2 Ⅰ TE represents a dual-mode bandpass resonator 201 Modulus, 1 Ⅱ 3 Ⅱ TE represents a single-mode band-stop resonator 101 Modulus, 2 Ⅱ TE represents a single-mode bandpass resonator 201 Mode, dual-mode resonator 2 Ⅰ and 2 Ⅱ It also forms a cross unit to achieve isolation between the two channels; Ch.1 represents channel one, and Ch.2 represents channel two.

[0039] Figure 6 This is a curve showing the coupling coefficient between the bandpass dual-mode resonator and the bandstop dual-mode resonator provided in this embodiment, as a function of the cross-slot lengths SL2 and SL3. K1 represents the TE between the dual-mode resonators. 102 The coupling coefficient is denoted by a slot line of length SL3 along the Y-axis in the cross-shaped slot line, and K2 represents the TE coupling between the two-mode resonators. 201 The coupling coefficient is determined by a groove of length SL2 along the X-axis in the cross-groove. As shown in the figure, the coupling coefficient K1 increases with increasing SL3, while SL2 hardly changes the coupling coefficient K1. The coupling coefficient K2 increases with increasing SL2, while SL3 hardly changes the coupling coefficient K2. The cross-groove achieves TE.102 and TE 201 Independent coupling of modules.

[0040] Figure 7 This is the S-parameter curve of channel one of the filter crossover of the present invention; the center frequency of the first frequency band is 8.78GHz, the -3dB bandwidth is 230MHz, the center frequency of the second frequency band is 9.43GHz, the -3dB bandwidth is 280MHz, and the dual-band isolation is greater than 28dB, the dual-band frequency ratio is 1.07, and the S-parameter curve of channel two is consistent with that of channel one. Figure 4 TE in 102 Model and TE 201 The symmetrical dual-coupling window, which features phase-opposite characteristics of the modes themselves, improves isolation compared to the single-coupling window set at the center of the four sides of the dual-mode resonator 10. This results in an improvement of 6.07 dB in isolation for the first frequency band and 7.11 dB in isolation for the second frequency band.

[0041] In summary, this invention, through its innovative shared resonant cavity structure, hybrid mode excitation mechanism, and multi-parameter independent control methods, achieves miniaturization of the duplexer while also possessing advantages such as adjustable bandwidth, high isolation, and flexible frequency ratio. It is suitable for the urgent needs of modern wireless communication systems for high-performance, small-size RF front-end devices.

[0042] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A high-isolation dual-band substrate integrated waveguide filter crossover, characterized in that, include: The dielectric layer (2), a top metal layer (1) located on the upper surface of the dielectric layer (2), an intermediate metal layer (3) located within the dielectric layer (2), a bottom metal layer (4) located on the lower surface of the dielectric layer (2), a first metallized via array (5), a second metallized via array (6), and a third metallized via array (7); the first metallized via array (5) penetrates the dielectric layer (2) and connects the top metal layer (1), the intermediate metal layer (3), and the bottom metal layer (4); the second metallized via array (6) connects the top metal layer (1) and the intermediate metal layer (3); the third metallized via array (7) connects the bottom metal layer (4) and the intermediate metal layer (3); It also includes a first input port, a first output port, a second input port, and a second output port; the dielectric layer (2), the top metal layer (1), the middle metal layer (3), the bottom metal layer (4), and the first metallized via array (5) constitute two SIW dual-mode resonant cavities and eight SIW single-mode resonant cavities; the SIW dual-mode resonant cavity specifically includes a third SIW mode resonator (10) and an eighth SIW resonator (15); the SIW single-mode resonant cavity specifically includes a first SIW resonator (8), a second SIW resonator (9), a fourth SIW resonator (11), a fifth SIW resonator (12), a sixth SIW resonator (13), a seventh SIW resonator (14), a ninth SIW resonator (16), and a tenth SIW resonator (17); The third SIW mode resonator (10), the eighth SIW resonator (15), the first SIW resonator (8), the second SIW resonator (9), the sixth SIW resonator (13), and the seventh SIW resonator (14) constitute channel one of the filter crossover; the first SIW resonator (8), the third SIW mode resonator (10), and the second SIW resonator (9) are bandpass resonators that constitute a bandpass response. The sixth SIW resonator (13), the eighth SIW resonator (15), and the seventh SIW resonator (14) are band-stop resonators that form a band-stop response to split the bandpass response and realize the dual-band response of channel one. The third SIW mode resonator (10), the eighth SIW resonator (15), the fourth SIW resonator (11), the fifth SIW resonator (12), the ninth SIW resonator (16), and the tenth SIW resonator (17) constitute channel two of the filter crossover. The fifth SIW resonator (12), the third SIW mode resonator (10), and the fourth SIW resonator (11) are bandpass resonators that constitute a bandpass response; The tenth SIW resonator (17), the eighth SIW resonator (15), and the ninth SIW resonator (16) are band-stop resonators that form a band-stop response to split the bandpass response and realize the dual-band response of channel two.

2. The high-isolation dual-band substrate integrated waveguide filter crossover according to claim 1, characterized in that, The first SIW resonator (8) and the third SIW resonator (10) share a common sidewall, and the common sidewall has symmetrically arranged first coupling windows; the second SIW resonator (9) and the third SIW resonator (10) share a common sidewall, and the common sidewall has symmetrically arranged second coupling windows; one of the non-common sidewalls of the first SIW resonator (8) has a first input window with a width of W01, and one of the non-common sidewalls of the third SIW resonator (9) also has a first output window with a width of W01; the first coupling window, the second coupling window, the first input window, and the first output window are not provided with a first metallized via array (5), and the third SIW resonator (10), the first SIW resonator (8), and the second SIW resonator (9) are provided with a second metallized via array (6).

3. The high-isolation dual-band substrate integrated waveguide filter crossover according to claim 1, characterized in that, The sixth SIW resonator (13) and the eighth SIW resonator (15) share a common sidewall, and no coupling window is provided on the common sidewall; the eighth SIW resonator (15) and the seventh SIW resonator (14) share a common sidewall, and no coupling window is provided on the common sidewall; a third metallized via array (7) is provided at the first input window position of the sixth SIW resonator (13), and a third metallized via array (7) is provided at the first output window of the seventh SIW resonator (14); no second metallized via array (6) is provided in the eighth SIW resonator (15), the sixth SIW resonator (13), the seventh SIW resonator (14), the ninth SIW resonator (16), and the tenth SIW resonator (17).

4. The high-isolation dual-band substrate integrated waveguide filter crossover according to claim 1, characterized in that, The fifth SIW resonator (12) and the third SIW resonator (10) share a common sidewall, and the common sidewall has symmetrically arranged third coupling windows; the fourth SIW resonator (11) and the third SIW resonator (10) share a common sidewall, and the common sidewall has symmetrically arranged fourth coupling windows; one of the non-common sidewalls of the first SIW resonator (12) has a second input window with a width of W02, and one of the non-common sidewalls of the fourth SIW resonator (11) also has a second output window with a width of W02; the third coupling window, the fourth coupling window, the second input window, and the second output window are not provided with a first metallized via array (5), and the fourth SIW resonator (11) and the fifth SIW resonator (12) are provided with a second metallized via array (6).

5. A high-isolation dual-band substrate integrated waveguide filter crossover according to claim 1, characterized in that, The tenth SIW resonator (17) and the eighth SIW resonator (15) share a common sidewall, and no coupling window is provided on the common sidewall; the eighth SIW resonator (15) and the ninth SIW resonator (16) share a common sidewall, and no coupling window is provided on the common sidewall; a third metallized via array (7) is provided at the second input window position of the tenth SIW resonator (17), and a third metallized via array (7) is provided at the second output window of the ninth SIW resonator (16).

6. The high-isolation dual-band substrate integrated waveguide filter crossover according to claim 1, characterized in that, The top metal layer (1) is connected to a first microstrip line at its first input window position, which serves as the input port of filter crossover channel one; the top metal layer (1) is connected to a second microstrip line at its first output window position, which serves as the first output port of filter crossover channel one; the top metal layer (1) is connected to a third microstrip line at its second input window position, which serves as the input port of filter crossover channel two; and the top metal layer (1) is connected to a fourth microstrip line at its second output window position, which serves as the second output port of filter crossover channel two.

7. A high-isolation dual-band substrate integrated waveguide filter crossover according to claim 1, characterized in that, The top metal layer (1) has an L-shaped groove on each side of the first microstrip line, the second microstrip line, the third microstrip line, and the fourth microstrip line.

8. A high-isolation dual-band substrate integrated waveguide filter crossover according to claim 1, characterized in that, By adjusting the lengths TSL1 and TSL2 of the L-shaped grooves on both sides of the microstrip line, the single-mode cavity TE can be controlled. 101 The power supply strength of the mode.

9. A high-isolation dual-band substrate integrated waveguide filter crossover according to claim 1, characterized in that, In the intermediate metal layer (1), grooves are formed along the edge of the first metallized via array (5) at the center of the cavities of the sixth SIW resonator (13), the seventh SIW resonator (14), the ninth SIW resonator (16), and the tenth SIW resonator (17), and the grooves are d1 away from the first metallized via array (5); a cross-shaped groove is formed at the center of the cavities of the eighth SIW resonator (15); the grooves in the intermediate metal layer are used to adjust the coupling strength between the upper bandpass resonator and the lower bandstop resonator, so as to achieve the effect of splitting a single frequency band into a dual frequency band.

10. A method for operating a high-isolation dual-band substrate integrated waveguide filter crossover, characterized in that, A high-isolation dual-band substrate integrated waveguide filter crossover based on any one of claims 1-9; an electromagnetic signal is input from the first microstrip line and excites the TE in the first SIW resonator (8). 101 mold; Among them, TE 101 The mode is coupled to the third SIW resonator (10) through a first symmetrical coupling window with a width of W1, thereby exciting the TE in the third SIW resonator (10). 102 The mode is then coupled to the second SIW resonator (9) through the second symmetrical coupling window with the same width W1; while the first SIW resonator (8), the second SIW resonator (9), and the third SIW mode resonator (10) are coupled to the lower sixth SIW resonator (13), the eighth SIW resonator (15), and the seventh SIW resonator (14) through the slot line along the Y-axis in the intermediate metal layer (3), so as to realize the response of the dual-band filter crossover channel one; The electromagnetic signal is input from the second microstrip line and excites TE in the fifth SIW mode resonator (12). 101 mold; Among them, TE 101 The mode is coupled to the third SIW mode resonator (10) through a third symmetrical coupling window with a width of W2, thereby exciting the TE in the third SIW mode resonator (10). 201 The mode is then coupled to the fourth SIW mode resonator (11) through the fourth symmetrical coupling window with the same width W2; while the third SIW mode resonator (10), the fourth SIW mode resonator (11), and the fifth SIW mode resonator (12) are coupled to the lower ninth SIW resonator (16), the eighth SIW resonator (15), and the tenth SIW resonator (17) through the slot line along the X-axis direction in the intermediate metal layer (3), thereby realizing the response of the second channel of the dual-band filter crossover. TE in the third SIW mode resonator (10) 102 Model and TE 201 The mode is a pair of orthogonal degenerate modes, providing dual-channel isolation; when the third SIW mode resonator (10) operates in mode two, the phases are opposite at the third coupling window and the fourth coupling window, and the energy coupled to the fifth SIW mode resonator (12) and the fourth SIW mode resonator (11) cancels out; similarly, when the third SIW mode resonator (10) operates in mode three, the phases are opposite at the first coupling window and the second coupling window, and the energy coupled to the fifth SIW mode resonator (12) and the fourth SIW mode resonator (11) also cancels out.

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