Miniaturized double-ridge dual-mode dielectric waveguide resonator and dual-passband filter comprising resonator

Abstract

The invention relates to a miniaturized double-ridge dual-mode dielectric waveguide resonator and a filter comprising the resonator. The resonator comprises a frequency adjusting blind hole in the center of the upper surface, and an upper ridge and a lower ridge which are arranged on the left side and the right side of the frequency adjusting blind hole respectively and are parallel to each other. The ridge waveguide has excellent physical characteristics of low dominant mode cut-off frequency, so that the resonator can independently control a dominant mode and a high-order mode and has the characteristic of miniaturization. The miniaturized four-order rectangular double-ridge dual-mode dual-passband dielectric waveguide filter is realized by adopting the resonator, the dual-passband filter controls the frequency of a main mode by utilizing the depth of a blind hole, adjusts the frequency of a high-order mode by utilizing the depth of the double ridges, and independently controls the coupling coefficient of low frequency and high frequency by utilizing the length of a coupling window and the depth of a slotting; and dual-mode independent control is achieved while the small size is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of communication equipment components, and in particular to a miniaturized double-ridged dual-mode dielectric waveguide resonator and a dual-passband filter comprising the resonator. Background Art

[0002] As 5G-Advanced has been deployed in major cities, the size, performance and cost of RF devices need to be further improved to meet its higher transmission rate and lower latency requirements. Dielectric waveguide filters are widely used in modern wireless communication systems due to their high quality factor, low insertion loss, high dielectric constant, wide temperature range and flexible input and output forms. By combining traditional ridge waveguide and dielectric waveguide filters, a dielectric ridge waveguide filter with better performance is formed, which is of great significance to the development of miniaturization of RF devices. However, the size of existing dielectric ridge waveguide filters is not small enough. At the same time, modern wireless communication systems need to cover more and more frequency bands. If one filter is used for one frequency band, the number of filters will increase. Dual-passband or multi-passband filters can solve this problem and reduce the number of filters. The design of dual-passband or multi-passband filters is more complicated than that of single-passband, which is mainly reflected in the independent controllability of each passband frequency and mode.

[0003] The shortcomings of the prior art mainly include two points: The first point is that the filter size is too large. The existing dual-mode independently controllable dual-passband dielectric waveguide filters are generally large in size and require printed circuit boards for coupling and feeding, which increases the complexity of filter design and manufacturing and increases production costs.

[0004] The second point is that there are few studies on dual-mode controllable dual-passband dielectric waveguide filters.

[0005] Based on this, the present invention proposes a rectangular double-ridged dual-mode dielectric waveguide resonator and a dual-passband filter including the resonator, which have the advantages of miniaturization, dual-mode controllability, high quality factor and low insertion loss. Summary of the invention

[0006] The purpose of the present invention is to solve the deficiencies in the above-mentioned prior art. The present invention proposes a miniaturized double-ridged dual-mode dielectric waveguide resonator and a filter including the resonator. The dielectric waveguide filter has the advantages of miniaturization, control of higher-order modes and low insertion loss.

[0007] In order to achieve the purpose of the present invention, the present invention provides a miniaturized double-ridged dual-mode dielectric waveguide resonator, including a dielectric waveguide resonator with a metallized surface, wherein a frequency adjustment blind hole is arranged on the upper surface of the dielectric waveguide resonator, an upper ridge with a rectangular cross-section is opened on the upper surface of the dielectric waveguide resonator, and a lower ridge with a rectangular cross-section is opened on the lower surface, wherein the upper ridge is parallel to the lower ridge and is arranged on the left and right sides of the frequency adjustment blind hole.

[0008] Furthermore, the dielectric waveguide resonator has a main mode quasi-TM 110 Mode, first high-order mode TM 120 The frequency adjustment blind hole is located at the center of the upper surface of the dielectric waveguide resonator and is used to adjust the main mode to the quasi-TEM mode. 110 mode and the resonant frequency of the second higher-order mode quasi-TEM mode, the upper ridge and the lower ridge are located at the first higher-order mode quasi-TM 120 The electric field of the mode is strong, which is used to control the first high-order mode TM 120 The resonant frequency of the mode.

[0009] In this resonator, the main mode is quasi-TM 110 The resonant frequencies of the first high-order mode and the second high-order mode quasi-TEM mode are independently adjusted by adjusting the depth of the frequency-adjusting blind hole. 120 The resonant frequencies of the modes are tuned independently by the depth of the upper and lower ridges.

[0010] In addition, the present invention also claims protection for a miniaturized fourth-order double-ridged dual-mode dielectric waveguide dual-passband filter having a surface metallized dielectric block, characterized in that: the dielectric block includes four aforementioned miniaturized double-ridged dual-mode dielectric waveguide resonators connected in sequence through first to third coupling diaphragms, from the input end to the output end, they are respectively the first dielectric waveguide resonator, the second dielectric waveguide resonator, the third dielectric waveguide resonator and the fourth dielectric waveguide resonator, the upper ridges and lower ridges of the four miniaturized double-ridged dual-mode dielectric waveguide resonators are respectively located on a straight line and penetrated, the lower surface of the first resonator is provided with an input-end metallized blind hole located below the upper ridge, the lower surface of the fourth resonator is provided with an output-end metallized blind hole located below the upper ridge, and the input probe and the output probe are respectively embedded in the input-end metallized blind hole and the output-end metallized blind hole for feeding.

[0011] The miniaturized fourth-order double-ridge dual-mode dielectric waveguide dual-passband filter of the present invention further comprises an input coaxial connector and an output coaxial connector, wherein the lower surface of the first dielectric waveguide resonator is provided with a first unmetallized ring connected to the input metallized blind hole, the lower surface of the fourth dielectric waveguide resonator is provided with a second unmetallized ring connected to the output metallized blind hole, the inner conductor of the input coaxial connector is connected to the input probe, and the outer conductor of the input coaxial connector is connected to the surface metal layer of the first dielectric waveguide resonator; the inner conductor of the output coaxial connector is connected to the output probe, and the outer conductor of the output coaxial connector is connected to the surface metal layer of the fourth dielectric waveguide resonator; the coupling strength of the input port is adjusted by adjusting the insertion depth of the input feeding probe, and the coupling strength of the output port is adjusted by adjusting the insertion depth of the output feeding probe.

[0012] Furthermore, the first to third coupling diaphragms are each provided with two vertical through holes located on both sides of the central axis, a coupling window is formed between the two vertical through holes located on the same coupling diaphragm, and the lower surfaces of the first to third coupling diaphragms are provided with first to third coupling grooves communicated with the lower ridge; the low-frequency coupling coefficient between adjacent resonators is independently adjusted by the spacing between the two through holes of the first, second and third coupling diaphragms, and the high-frequency coupling coefficient between adjacent resonators is independently adjusted by the depth of the first, second and third coupling grooves.

[0013] Furthermore, a first coupling adjustment blind hole for fine-tuning the high-frequency coupling coefficient between the second dielectric waveguide resonator and the third dielectric waveguide resonator is provided on the upper surface of the second diaphragm; and a second coupling adjustment blind hole for fine-tuning the high-frequency coupling coefficient between the third dielectric waveguide resonator and the fourth dielectric waveguide resonator is provided on the upper surface of the third diaphragm.

[0014] The signal is fed into the first dielectric waveguide resonator from the input coaxial connector via the input feeding probe and the input metallized blind hole, coupled through the first coupling diaphragm to achieve source-load coupling, and then sequentially coupled to the fourth dielectric waveguide resonator through the second dielectric waveguide resonator, the second coupling diaphragm, the third dielectric waveguide resonator, and the third coupling diaphragm, and then output from the output coaxial connector after passing through the output metallized blind hole and the output feeding probe.

[0015] The miniaturized double-ridged dual-mode dielectric waveguide resonator of the present invention is based on the original rectangular dielectric waveguide, a blind hole is opened in the center of the upper surface, a rectangular ridge is opened at one-quarter of the side length of the upper surface and three-quarters of the side length of the lower surface, and the ridge waveguide has an excellent physical property of low main mode cutoff frequency to form a double-ridged dielectric resonator. This resonator can independently control the main mode and the high-order mode and has the characteristics of miniaturization.

[0016] A miniaturized fourth-order rectangular double-ridged dual-mode dual-passband dielectric waveguide filter is realized by using a miniaturized double-ridged dielectric waveguide resonator. The dual-passband filter uses the depth of the blind hole to control the main mode frequency, and the depth of the double ridges to adjust the high-order mode frequency. At the same time, the coupling window length and the slot depth are used to independently control the coupling coefficient of the low frequency and the high frequency, thereby achieving small size and dual-mode independent control. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be further described below in conjunction with the accompanying drawings; Figure 1 It is a schematic diagram of the three-dimensional structure of the double-ridged dual-mode dielectric waveguide resonator of the present invention.

[0018] Figure 2 The electric field distribution of the first two modes of the rectangular ridgeless dielectric waveguide resonator, with TM on the left. 110 Electric field distribution of the mode, TM on the right 120 Electric field distribution diagram of the mode.

[0019] Figure 3 The electric field distribution diagram of the three modes of the double-ridge dual-mode dielectric waveguide resonator of the present invention: (a) Quasi-TM 110 mode; (b) quasi-TM 120 mode; (c) quasi-TEM mode.

[0020] Figure 4 The frequency adjustment blind hole depth of the double-ridge dual-mode dielectric waveguide resonator of the present invention is h 1 Simulation results of the impact on the first three modes: (a) resonant frequency; (b) no-load quality factor Q u .

[0021] Figure 5 is the double ridge depth of the dielectric waveguide resonator of the present invention h u Simulation results of the impact on the first three modes: (a) resonant frequency and (b) unloaded quality factor Q u .

[0022] Figure 6 A three-dimensional structural diagram of the fourth-order rectangular double-ridge dual-mode dual-passband dielectric waveguide filter of the present invention.

[0023] Figure 7 It is a top view of the invented fourth-order rectangular double-ridged dual-mode dual-passband dielectric waveguide filter.

[0024] Figure 8 It is a coupling topology diagram of the invented fourth-order rectangular double-ridge dual-mode dual-passband dielectric waveguide filter.

[0025] Fig. 9It is the S-parameter simulation result of the invented fourth-order rectangular double-ridge dual-mode dual-passband dielectric waveguide filter.

[0026] Fig.10 The invention is a fourth-order rectangular double-ridge dual-mode dual-passband dielectric waveguide filter with frequency-dependent blind hole depth adjustment. h Simulation results of the variation of 1: (a) low frequency; (b) high frequency.

[0027] Fig.11 The frequency of the fourth-order rectangular double-ridge dual-mode dual-passband dielectric waveguide filter varies with the depth of the double ridges. h u Simulation results of the variation of: (a) low frequency and (b) high frequency.

[0028] Fig.12 is the low frequency coupling coefficient between the first resonator DR1 and the second resonator DR2 in the invented filter k 12 , high frequency coupling coefficient k 56 Curves of changes with parameters: (a) First coupling window length (the spacing of the vertical through holes of the first coupling diaphragm) l c1 ; (b) Depth of the first coupling groove h c1 .

[0029] Fig.13 is the low frequency coupling coefficient between the second resonator DR2 and the third resonator DR3 in the invented filter k 23 , high frequency coupling coefficient k 67 Curves of changes with parameters: (a) Second coupling window length (the spacing of the vertical through holes of the second coupling diaphragm) l c2 ; (b) Depth of the second coupling groove h c2 ; (c) Depth of the first coupling blind hole h m1 .

[0030] Fig.14 The external quality factor of the invented filter Q e Length from the center of the feed probe to the center of the resonator l p1 The change curve.

[0031] Fig.15 The external quality factor of the invented filter Q e Feeding probe depth h p1 The change curve. DETAILED DESCRIPTION

[0032] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. Example

[0033] like Figure 1 As shown, the miniaturized double-ridge dual-mode dielectric waveguide resonator of this embodiment has a three-dimensional structure as shown in Figure 1 As shown. It includes a rectangular dielectric waveguide resonator with a metallized (silver-plated) surface, a frequency adjustment blind hole C is arranged on the upper surface of the rectangular dielectric waveguide resonator, an upper ridge A with a rectangular cross section is opened on the upper surface of the dielectric waveguide resonator, and a lower ridge B with a rectangular cross section is opened on the lower surface. The upper ridge A is parallel to the lower ridge B (specifically, the upper ridge A and the lower ridge B are both arranged parallel to the X-axis) and are arranged on the left and right sides of the frequency adjustment blind hole C.

[0034] like Figure 2 The electric field distribution of the first two modes of the rectangular ridgeless dielectric waveguide resonator is shown in Figure 2. The main mode TM 110 The strongest point of the electric field is at the center of the resonator, and its first high-order mode TM 120 The strongest points of the electric field are located at one quarter and three quarters of the central axis respectively. Therefore, the present invention is based on a rectangular ridgeless dielectric waveguide resonator, and a frequency adjustment blind hole C is set at the center of the resonator to control the main mode (quasi-TM 110 mode) and the second higher-order mode (quasi-TEM mode), a rectangular ridge (upper ridge A and lower ridge B) is dug out at one-quarter and three-quarters of the central axis of the resonator to control the first higher-order mode (quasi-TM mode). 120 mode), their electric field distribution is as follows Figure 3 The two rectangular ridges are located at one quarter of the upper surface and three quarters of the lower surface, respectively, to facilitate the setting of the coaxial connector for feeding.

[0035] When changing the blind hole depth h 1 and other parameters remain unchanged, the simulation results of the resonant frequency and no-load quality factor of the resonator are as follows Figure 4 As shown, the deeper the frequency adjustment blind hole, the closer the TM 110 The resonance frequencies of the quasi-TEM mode and the quasi-TM mode are smaller, while the 120 The resonant frequencies of the modes are very stable, and their unloaded quality factors are reduced. h u = h b ) and other parameters remain unchanged, the simulation results of the resonant frequency and no-load quality factor of the resonator are as follows Figure 5 As shown, compared with the quasi-TM 110 The resonant frequencies of the mode and quasi-TEM mode decrease slowly, and the quasi-TM 120The resonant frequency of the first three modes is greatly reduced, and their unloaded quality factors are also reduced. It can be seen from the above that the depth of the frequency-adjusting blind hole and the double ridge depth in the resonator can control the resonant frequency and quality factor of the first three modes, and the unloaded quality factor of the resonator used in the present invention can be maintained above 1390. The main mode of the resonator is quasi-TM 110 The resonant frequencies of the first and second higher-order modes, the quasi-TEM mode, and the second higher-order mode are independently adjusted by adjusting the depth of the frequency-adjusting blind hole C. 120 The resonant frequencies of the modes are independently tuned by the depths of the upper A and lower B ridges. Example

[0036] This embodiment discloses a miniaturized fourth-order dielectric waveguide dual-passband filter based on a rectangular double-ridge dual-mode resonator, and its three-dimensional structure is as follows: Figure 6 , top view Figure 7 As shown, it includes: a dielectric block, an input coaxial connector 1 and an output coaxial connector 6. The coupling topology of the filter is shown in Figure 8 .

[0037] The dielectric block can be made of dielectric ceramic material by firing, and its outer surface is silver-plated to achieve metallization except for the first unmetallized ring 2 and the second unmetallized ring 5. The dielectric block includes four rectangular double-ridge dielectric waveguide resonators of the first embodiment coupled in sequence, such as Figure 6 , Figure 8 As shown, from the input end to the output end are the first dielectric waveguide resonator DR1, the second dielectric waveguide resonator DR2, the third dielectric waveguide resonator DR3, and the fourth dielectric waveguide resonator DR4. A first frequency adjustment blind hole C1 is provided at the center of the upper surface of the first dielectric waveguide resonator DR1, and its depth is h 1. Diameter r 1. A second frequency adjustment blind hole C2 is provided at the center of the upper surface of the second dielectric waveguide resonator DR2, and its depth is h 1. Diameter r 2. A third frequency adjustment blind hole C3 is provided at the center of the upper surface of the third dielectric waveguide resonator DR3, and its depth is h 1. Diameter r 2. A fourth frequency adjustment blind hole C4 is provided at the center of the upper surface of the fourth dielectric waveguide resonator DR4, and its depth is h 1. Diameter r 3.

[0038] Adjacent resonators are coupled via coupling diaphragms. Specifically, Figure 6As shown, the first dielectric waveguide resonator DR1 and the second dielectric waveguide resonator DR2 are coupled to each other through the first coupling diaphragm 7, the second dielectric waveguide resonator DR2 and the third dielectric waveguide resonator DR3 are coupled to each other through the second coupling diaphragm 8, and the third dielectric waveguide resonator DR3 and the fourth dielectric waveguide resonator DR4 are coupled to each other through the third coupling diaphragm 9, and the energy is coupled to the next-stage resonator through the coupling diaphragms in sequence. Figure 6 In the figure, A is the upper ridge opened at one quarter of the side length of the upper surface, and B is the lower ridge opened at three quarters of the side length of the lower surface. It can be seen that in this filter, the upper ridge A and the lower ridge B of the four dielectric waveguide resonators are respectively located on a straight line and connected, and the through-length upper ridge A and lower ridge B can be formed on the dielectric block at one time, making its processing more convenient.

[0039] The lower surface of the first resonator DR1 is provided with an input-end metallized blind hole 3 located below the upper ridge A, and the lower surface of the fourth resonator DR4 is provided with an output-end metallized blind hole 4 located below the upper ridge A. Both blind holes are not located at the exact center and have the same height. In this example, the first unmetallized ring 2 is connected to the input-end metallized blind hole 3, and the second unmetallized ring 5 is connected to the output-end metallized blind hole 4. The inner conductor of the input-end coaxial connector 1 is connected to the input probe P1, and the outer conductor is connected to the surface metal layer of the first dielectric waveguide resonator DR1. The inner conductor of the output-end coaxial connector 6 is connected to the output probe P2, and the outer conductor is connected to the surface metal layer of the fourth dielectric waveguide resonator DR4. The input probe P1 and the output probe P2 are respectively embedded in the input-end metallized blind hole 3 and the output-end metallized blind hole 4 for feeding. The coupling strength of the input port is adjusted by adjusting the insertion depth of the input feeding probe P1, and the coupling strength of the output port is adjusted by adjusting the insertion depth of the output feeding probe P2.

[0040] like Figure 6 , Figure 7 As shown, the first coupling diaphragm 7, the second coupling diaphragm 8, and the third coupling diaphragm 9 are provided with two vertical through holes of different sizes located on both sides of the central axis, and a coupling window is formed between the two vertical through holes located in the same coupling diaphragm. Figure 7 As shown, the coupling window length of the first coupling membrane 7 and the third coupling membrane 9 is l c1 , the coupling window length of the second coupling membrane 8 is l c2 . w 1. w 2 and w 3 are the widths of the coupling membranes. The first coupling membrane 7 has a first coupling groove 10 communicating with the lower ridge B on its lower surface, the second coupling membrane 8 has a first coupling groove 11 communicating with the lower ridge B on its lower surface, and the third coupling membrane 9 has a third coupling groove 12 communicating with the lower ridge B on its lower surface.h c1 , h c2 and h c3 The experiments show that the low-frequency coupling coefficient between adjacent resonators can be independently adjusted by the distance between the two through holes of the first, second and third coupling diaphragms (the length of the coupling window), and the high-frequency coupling coefficient between adjacent resonators can be independently adjusted by the depth of the first, second and third coupling grooves.

[0041] like Figure 6 In the embodiment described above, a first coupling adjustment blind hole 13 is provided on the upper surface of the second diaphragm 8 for fine-tuning the high-frequency coupling coefficient between the second dielectric waveguide resonator DR2 and the third dielectric waveguide resonator DR3, and the depth of the first coupling adjustment blind hole 13 is h m1 , diameter is r m1 The third diaphragm 9 is provided on the upper surface thereof with a second coupling adjustment blind hole 14 for fine-tuning the high-frequency coupling coefficient between the third dielectric waveguide resonator DR3 and the fourth dielectric waveguide resonator DR4, and the depth thereof is h m2 , diameter is r m1 The outer ring diameter at the input coaxial connector 1 and the output coaxial connector 6 w out is the inner ring diameter w in 2.6 times of the resistance is used to ensure 50Ω port matching.

[0042] The working process of the fourth-order filter is described below: The signal is input from the input coaxial connector 1, fed into the first dielectric waveguide resonator DR1 through the input feeding probe P1 and the input metallized blind hole 3, coupled through the first coupling diaphragm 7 to achieve source-load coupling, and then sequentially coupled to the fourth dielectric waveguide resonator DR4 through the second dielectric waveguide resonator DR2, the second coupling diaphragm 8, the third dielectric waveguide resonator DR3, and the third coupling diaphragm 9, and output from the output coaxial connector 6 after passing through the output metallized blind hole 4 and the output feeding probe P2.

[0043] The parameters of the filter in the embodiment of the present invention are shown in the following table:

[0044] In the table, w all is the total width of the dual passband filter, l is the length of the dual passband filter, h is the thickness of the dual passband filter, h1 is the depth of the blind hole C1 adjusted by the first frequency, the blind hole C2 adjusted by the second frequency, the blind hole C3 adjusted by the third frequency, and the blind hole C4 adjusted by the fourth frequency. r 1 is the diameter of the blind hole C1 for the first frequency adjustment, r 2 is the diameter of the blind hole C2 adjusted by the second frequency and the blind hole C3 adjusted by the third frequency. r 3 is the diameter of the blind hole C4 adjusted by the fourth frequency, w cr is the outer ring diameter of the first unmetallized ring 2 and the second unmetallized ring 5, r m1 is the diameter of the first coupling adjustment blind hole 13 and the second coupling adjustment blind hole 14, h m1 The depth of the blind hole 13 is adjusted for the first coupling, h m2 Adjust the depth of the blind hole 14 for the second coupling, h c1 is the depth of the first coupling groove, h c2 is the depth of the second coupling groove, h c3 is the depth of the third coupling groove, w in is the inner ring diameter of the input end coaxial connector 1 and the output end coaxial connector 6, and is also the inner ring diameter of the first unmetallized circular ring 2 and the second unmetallized circular ring 5, w out is the outer ring diameter of the input coaxial connector 1 and the output coaxial connector 6, w 1 is the width of the first coupling diaphragm 7, w 2 is the width of the second coupling diaphragm 8, w 3 is the width of the third coupling diaphragm 9, l c1 is the coupling window length of the first coupling diaphragm 7 and the third coupling diaphragm 9, l c2 is the coupling window length of the second coupling diaphragm 8, l p1 is the distance from the center of the feeding probe to the center of the resonator, h p1 is the feed probe depth, w u is the width of the upper ridge A, w b is the width of the lower ridge B, h u is the depth of the upper ridge A, h b is the depth of the lower ridge B.

[0045] The simulation results of the miniaturized fourth-order rectangular double-ridge dual-mode dual-passband dielectric waveguide filter of this embodiment are shown in FIG. Fig. 9 As shown in the figure, the filter passbands are low frequency 2570-2650MHz and high frequency 3400-3500MHz, covering the two frequency bands of 2570-2620MHz of n38 and 3400-3500MHzz of n78. The low frequency center frequency is 2615MHz, the maximum insertion loss is 0.46dB, the working bandwidth is 80MHz, and the relative bandwidth is 3%; the high frequency center frequency is 3450MHz, the maximum insertion loss is 0.46dB, the working bandwidth is 100MHz, and the relative bandwidth is 2.9%. Harmonics are at 4150MHz.

[0046] To further illustrate the filter's dual-mode independent controllability, Figure 8 The coupled topology of dual-passband filter is given. Fig.10 It shows that as the depth of the resonator blind hole increases h 1 increases, the low-frequency passband of the filter moves toward low frequencies as a whole, while the high-frequency passband remains basically unchanged; Fig.11 It shows that as the depth of the double ridge of the resonator increases h u (Right now h u = h b ) increases at the same time, the high-frequency passband of the filter obviously moves toward the low frequency as a whole, and the low-frequency passband moves slightly toward the low frequency. Compared with the movement of the high-frequency passband, the movement of the low-frequency passband is much smaller. Fig.10 and Fig.11 , which shows that the two passband frequencies of the dual-passband filter are independently controllable by the blind hole depth and double ridge depth in the resonator.

[0047] Figure 12-13 The curves showing some parameters that affect the coupling coefficient between resonators are shown. Figure 14-15 The corresponding external quality factor increases with the depth of the feed probe. h p1 and location l p1 The changing curve. k 12 The quasi-TM between the first dielectric waveguide resonator DR1 and the second dielectric waveguide resonator DR2 at low frequency 110 The mode coupling coefficient, k 56 The quasi-TM between the first dielectric waveguide resonator DR1 and the second dielectric waveguide resonator DR2 at high frequencies 120 The coupling coefficient of the mode is given by Fig.12 It can be seen that as the distance between the two through holes (coupling window length)l c1 increase, k 12 Significantly larger. k 56 Basically remain unchanged; as the depth of the first coupling groove 10 on the lower surface of the coupling window increases h c1 increase, k 12 and k 56 are reduced. Similarly, k 23 The quasi-TM between the second dielectric waveguide resonator DR2 and the third dielectric waveguide resonator DR3 at low frequency 110 The mode coupling coefficient, k 67 The quasi-TM between the second dielectric waveguide resonator DR2 and the third dielectric waveguide resonator DR3 at high frequencies 120 The coupling coefficient of the mode is given by Fig.13 It can be seen that as the distance between the two through holes (the coupling window length of the second coupling diaphragm) l c2 increase, k 23 Significantly larger. k 67 Basically remain unchanged; as the depth of the second coupling groove 11 dug on the lower surface of the coupling window h c2 increase, k 67 Reduce, k 23 Only a small change; with the first coupling adjustment of the blind hole 13 on the upper surface of the coupling window h m1 increase, k 23 and k 67 All increased.

[0048] Theoretically, when the coupling coefficient between resonators changes, the corresponding external quality factor will also change. Figure 14-15 The external quality factor of the filter varies with the feed probe position. l p1 , Probe Depth h p1 As the feeding probe position l p1 Get bigger, TM 120 Pattern Q e Reduced, quasi-TM 110 PatternQ e. Slowly increase; feed probe depth h p1 The increase will make Q e Reduce. Comprehensive Figure 12-Figure 15 , which shows that the dual-passband dielectric waveguide filter is capable of independently controlling the dual modes.

[0049] The fourth-order dual-mode dual-passband dielectric waveguide filter utilizes two rectangular ridges to independently control the dual modes while reducing the volume of the filter, and also reduces the manufacturing cost, has a lower insertion loss, and has high practicality.

[0050] The above simulation results are all computer simulation results.

[0051] In addition to the above embodiments, the present invention may also have other implementation modes. Any technical solution formed by equivalent replacement or equivalent transformation falls within the protection scope required by the present invention.

Claims

1. A miniaturized double-ridge dual-mode dielectric waveguide resonator, comprising a surface metallized dielectric waveguide resonator, wherein a frequency adjustment blind hole (C) is arranged on the upper surface of the dielectric waveguide resonator, an upper ridge (A) with a rectangular cross section is opened on the upper surface of the dielectric waveguide resonator, and a lower ridge (B) with a rectangular cross section is opened on the lower surface, wherein the upper ridge (A) is parallel to the lower ridge (B) and is arranged on the left and right sides of the frequency adjustment blind hole (C).

2. The miniaturized double-ridged dual-mode dielectric waveguide resonator according to claim 1, characterized in that: The dielectric waveguide resonator has a dominant mode quasi-TM 110 Mode, first high-order mode TM 120 mode and the second high-order mode quasi-TEM mode. The frequency adjustment blind hole (C) is located at the center of the upper surface of the dielectric waveguide resonator to adjust the main mode quasi-TM 110 The resonant frequencies of the mode and the second higher-order quasi-TEM mode, the upper ridge (A) and the lower ridge (B) are located at the first higher-order quasi-TM mode 120 The electric field of the mode is strong, which is used to control the first high-order mode TM 120 The resonant frequency of the mode.

3. The miniaturized double-ridged dual-mode dielectric waveguide resonator according to claim 2, characterized in that: The upper ridge (A) and the lower ridge (B) are located at one quarter and three quarters of the central axis of the dielectric waveguide resonator, respectively, and the depth of the upper ridge (A) is equal to the depth of the lower ridge (B).

4. The miniaturized double-ridged dual-mode dielectric waveguide resonator according to claim 1, characterized in that: The master model TM 110 The resonant frequencies of the first high-order mode and the second high-order mode quasi-TEM mode are independently adjusted by adjusting the depth of the frequency-adjusting blind hole (C). 120 The resonant frequencies of the modes are independently tuned by the depth of the upper ridge (A) and the lower ridge (B).

5. A miniaturized fourth-order double-ridged dual-mode dielectric waveguide dual-passband filter having a surface metallized dielectric block, characterized in that: The dielectric block comprises four miniaturized double-ridged dual-mode dielectric waveguide resonators as claimed in claim 1, which are connected in sequence through first to third coupling membranes (7, 8, 9). From the input end to the output end, they are respectively the first dielectric waveguide resonator (DR1), the second dielectric waveguide resonator (DR2), the third dielectric waveguide resonator (DR3) and the fourth dielectric waveguide resonator (DR4). The upper ridge (A) and the lower ridge (B) of the four miniaturized double-ridged dual-mode dielectric waveguide resonators are respectively located on a straight line and are connected. The lower surface of the first resonator (DR1) is provided with an input-end metallized blind hole (3) located below the upper ridge (A). The lower surface of the fourth resonator (DR4) is provided with an output-end metallized blind hole (4) located below the upper ridge (A). The input probe (P1) and the output probe (P2) are respectively embedded in the input-end metallized blind hole (3) and the output-end metallized blind hole (4) for feeding.

6. The miniaturized fourth-order double-ridged dual-mode dielectric waveguide dual-passband filter according to claim 5, characterized in that: The invention also comprises an input end coaxial connector (1) and an output end coaxial connector (6); the lower surface of the first dielectric waveguide resonator (DR1) is provided with a first unmetallized circular ring (2) connected to the input end metallized blind hole (3); the lower surface of the fourth dielectric waveguide resonator (DR4) is provided with a second unmetallized circular ring (5) connected to the output end metallized blind hole (4); the inner conductor of the input end coaxial connector (1) is connected to the input probe (P1); the outer conductor of the input end coaxial connector (1) is connected to the surface metal layer of the first dielectric waveguide resonator (DR1); the inner conductor of the output end coaxial connector (6) is connected to the output probe (P2); the outer conductor of the output end coaxial connector (6) is connected to the surface metal layer of the fourth dielectric waveguide resonator (DR4); the coupling strength of the input port is adjusted by adjusting the insertion depth of the input feeding probe (P1); and the coupling strength of the output port is adjusted by adjusting the insertion depth of the output feeding probe (P2).

7. The miniaturized fourth-order double-ridged dual-mode dielectric waveguide dual-passband filter according to claim 5, characterized in that: The first to third coupling diaphragms (7, 8, 9) are each provided with two vertical through holes located on both sides of the central axis, a coupling window is formed between the two vertical through holes located on the same coupling diaphragm, and the lower surfaces of the first to third coupling diaphragms (7, 8, 9) are provided with first to third coupling grooves (10, 11, 12) communicating with the lower ridge (B); the low-frequency coupling coefficient between adjacent resonators is independently adjusted by the spacing between the two through holes of the first, second and third coupling diaphragms (7, 8, 9), and the high-frequency coupling coefficient between adjacent resonators is independently adjusted by the depth of the first, second and third coupling grooves (10, 11, 12).

8. The miniaturized fourth-order double-ridged dual-mode dielectric waveguide dual-passband filter according to claim 7, characterized in that: The upper surface of the second diaphragm (8) is provided with a first coupling adjustment blind hole (13) for fine-tuning the high-frequency band coupling coefficient between the second dielectric waveguide resonator (DR2) and the third dielectric waveguide resonator (DR3); and the upper surface of the third diaphragm (9) is provided with a second coupling adjustment blind hole (14) for fine-tuning the high-frequency band coupling coefficient between the third dielectric waveguide resonator (DR3) and the fourth dielectric waveguide resonator (DR4).

9. The miniaturized fourth-order double-ridged dual-mode dielectric waveguide dual-passband filter according to claim 7, characterized in that: The spacing between the two vertical through holes of the first coupling diaphragm (7) is equal to the spacing between the two vertical through holes of the third diaphragm coupling diaphragm (9).

10. The miniaturized fourth-order double-ridged dual-mode dielectric waveguide dual-passband filter according to any one of claims 5 to 8, characterized in that: The signal is fed from the input end coaxial connector (1) through the input feeding probe (P1) and the input end metallized blind hole (3) into the first dielectric waveguide resonator (DR1), coupled through the first coupling diaphragm (7) to achieve source-load coupling, and then sequentially coupled through the second dielectric waveguide resonator (R2), the second coupling diaphragm (8), the third dielectric waveguide resonator (DR3), and the third coupling diaphragm (9) to the fourth dielectric waveguide resonator (DR4), and output from the output end coaxial connector (6) after passing through the output end metallized blind hole (4) and the output feeding probe (P2).

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