A miniaturized double-ridge dual-mode dielectric waveguide resonator and a double-passband filter comprising the resonator

Abstract

The application relates to a miniaturized double-ridge double-mode dielectric waveguide resonator and a filter containing the resonator. The resonator comprises a frequency adjusting blind hole at the center of the upper surface, and upper and lower ridges which are arranged on the left and right sides of the frequency adjusting blind hole and are parallel to each other. The resonator can independently control the main mode and the high-order mode and has the characteristics of miniaturization by using the excellent physical characteristics of the ridge waveguide which has a low main mode cutoff frequency. The application realizes a miniaturized four-order rectangular double-ridge double-mode double-passband dielectric waveguide filter by using the resonator. The double-passband filter controls the main mode frequency by using the blind hole depth, adjusts the high-order mode frequency by using the double-ridge depth, and independently controls the low-frequency and high-frequency coupling coefficients by using the coupling window length and the slot depth, so that the double-mode independent control is realized while the size is small.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of communication device components, in particular to a miniaturized double-ridge dual-mode dielectric waveguide resonator and a double-passband filter comprising the resonator. BACKGROUND

[0002] With the deployment of 5G-Advanced in major cities, in order to adapt to its higher transmission rate and lower latency requirements, the size, performance and cost of radio frequency devices need to be further improved. 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 / output form. 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 miniaturization of radio frequency devices. However, the existing dielectric ridge waveguide filter is still 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, and a double-passband or multi-passband filter can solve this problem and reduce the number of filters. The design of a double-passband or multi-passband filter is more complex than that of a single-passband filter, mainly in the independent controllability of each passband frequency and mode.

[0003] The main disadvantages of the prior art are as follows:

[0004] The first point is that the filter size is too large. The existing double-mode independently controllable double-passband dielectric waveguide filter is generally large in size, and needs a printed circuit board for coupling and feeding, which increases the complexity of the filter in design and manufacturing, and also increases the manufacturing cost.

[0005] The second point is that there is little research on double-mode controllable double-passband dielectric waveguide filters.

[0006] Therefore, the present application proposes a rectangular double-ridge dual-mode dielectric waveguide resonator and a double-passband filter comprising the resonator, which has the advantages of miniaturization, dual-mode controllability, high quality factor and low insertion loss. SUMMARY

[0007] The present application aims to solve the above-mentioned problems in the prior art. The present application proposes a miniaturized double-ridge dual-mode dielectric waveguide resonator and a filter comprising the resonator, which has the advantages of miniaturization, control of high-order modes and low insertion loss.

[0008] In order to achieve the object of the present application, the present application provides a miniaturized double-ridge double-mode dielectric waveguide resonator, comprising a surface metallized dielectric waveguide resonator, the upper surface of the dielectric waveguide resonator is provided with a frequency adjustment blind hole, the upper surface of the dielectric waveguide resonator is provided with an upper ridge with a rectangular cross section, and the lower surface is provided with a lower ridge with a rectangular cross section, the upper ridge and the lower ridge are parallel and arranged on the left and right sides of the frequency adjustment blind hole.

[0009] Further, the dielectric waveguide resonator has a main mode quasi-TM 110 mode, a first high-order mode quasi-TM 120 mode and a second high-order mode quasi-TEM mode, the frequency adjustment blind hole is located at the center of the upper surface of the dielectric waveguide resonator, and is used for adjusting the resonant frequencies of the main mode quasi-TM 110 mode and the second high-order mode quasi-TEM mode, the upper ridge and the lower ridge are located at the positions where the electric field of the first high-order mode quasi-TM 120 mode is strong, and are used for controlling the resonant frequency of the first high-order mode quasi-TM 120 mode.

[0010] In the present resonator, the resonant frequencies of the main mode quasi-TM 110 mode and the second high-order mode quasi-TEM mode are independently adjusted by the depth of the frequency adjustment blind hole, and the resonant frequency of the first high-order mode quasi-TM 120 mode is independently adjusted by the depths of the upper ridge and the lower ridge.

[0011] In addition, the present application also claims a miniaturized four-order double-ridge double-mode dielectric waveguide double-passband filter, comprising a surface metallized dielectric block, characterized in that: the dielectric block comprises four aforementioned miniaturized double-ridge double-mode dielectric waveguide resonators connected in sequence through first to third coupling diaphragms, and from the input end to the output end, they are a first dielectric waveguide resonator, a second dielectric waveguide resonator, a third dielectric waveguide resonator and a fourth dielectric waveguide resonator, respectively, the upper ridges and the lower ridges of the four miniaturized double-ridge double-mode dielectric waveguide resonators are located on a straight line and penetrate through, the lower surface of the first dielectric waveguide resonator is provided with an input end metallized blind hole located below the upper ridge, the lower surface of the fourth dielectric waveguide resonator is provided with an output end metallized blind hole located below the upper ridge, and the input feed probe and the output feed probe are embedded in the input end metallized blind hole and the output end metallized blind hole for feeding.

[0012] The miniaturized four-order double-ridge double-mode dielectric waveguide dual-band filter also has an input end coaxial connector and an output end coaxial connector, the lower surface of the first dielectric waveguide resonator is provided with a first unmetallized circular ring connected with the input end metallized blind hole, the lower surface of the fourth dielectric waveguide resonator is provided with a second unmetallized circular ring connected with the output end metallized blind hole, the inner conductor of the input end coaxial connector is connected with the input feed probe, and the outer conductor of the input end coaxial connector is connected with the surface metal layer of the first dielectric waveguide resonator; the inner conductor of the output end coaxial connector is connected with the output feed probe, and the outer conductor of the output end coaxial connector is connected with the surface metal layer of the fourth dielectric waveguide resonator; the input port coupling strength is adjusted by adjusting the insertion depth of the input feed probe, and the output port coupling strength is adjusted by adjusting the insertion depth of the output feed probe.

[0013] Further, the first to third coupling diaphragms are each provided with two vertical through holes located on both sides of the central axis, and a coupling window is formed between the two vertical through holes of the same coupling diaphragm; the lower surfaces of the first to third coupling diaphragms are provided with first to third coupling grooves in communication with the lower ridge; the low-frequency coupling coefficient between adjacent resonators is independently adjusted by the spacing of 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.

[0014] Still further, the upper surface of the second coupling diaphragm is provided with a first coupling adjustment blind hole for fine adjustment of the high-frequency coupling coefficient between the second dielectric waveguide resonator and the third dielectric waveguide resonator; and the upper surface of the third coupling diaphragm is provided with a second coupling adjustment blind hole for fine adjustment of the high-frequency coupling coefficient between the third dielectric waveguide resonator and the fourth dielectric waveguide resonator.

[0015] The signal is fed into the first dielectric waveguide resonator through the input feed probe and the input end metallized blind hole, coupled through the first coupling diaphragm to realize source load coupling, then sequentially passes through the second dielectric waveguide resonator, the second coupling diaphragm, the third dielectric waveguide resonator and the third coupling diaphragm to be coupled to the fourth dielectric waveguide resonator, and is output from the output end coaxial connector after passing through the output end metallized blind hole and the output feed probe.

[0016] The miniaturized double-ridge double-mode dielectric waveguide resonator is based on the original rectangular dielectric waveguide, a blind hole is formed in the center of the upper surface, a rectangular ridge is formed at one quarter of the length of the upper surface and three quarters of the length of the lower surface, respectively, and the ridge waveguide has excellent physical properties of low main mode cutoff frequency, so that it forms a double-ridge dielectric resonator. This resonator can independently control the main mode and high-order mode and has the characteristics of miniaturization.

[0017] A four-order rectangular double-ridge double-mode double-passband dielectric waveguide filter is realized by using a miniaturized double-ridge dielectric waveguide resonator, the double-passband filter uses blind hole depth to control the main mode frequency, uses the depth of the double-ridge to adjust the high-order mode frequency, and simultaneously uses the coupling window length and the slot depth to independently control the coupling coefficients of the low frequency and the high frequency, so that the double-mode is independently controlled while the small size is realized. BRIEF DESCRIPTION OF DRAWINGS

[0018] The application will be further described below with reference to the drawings;

[0019] Figure 1 Fig. 1 is a three-dimensional structural diagram of a double-ridge double-mode dielectric waveguide resonator of the application.

[0020] Figure 2 Fig. 2 is a diagram of the electric field distribution of the first two modes of a rectangular ridgeless dielectric waveguide resonator, the left side is the electric field distribution diagram of the TM 110 mode, and the right side is the electric field distribution diagram of the TM 120 mode.

[0021] Figure 3 Fig. 3 is a diagram of the electric field distribution of the three modes of the double-ridge double-mode dielectric waveguide resonator of the application: (a) quasi-TM 110 mode; (b) quasi-TM 120 mode; (c) quasi-TEM mode.

[0022] Figure 4 Fig. 4 is a simulation result of the influence of the blind hole depth h 1 on the first three modes: (a) resonant frequency and (b) unloaded quality factor Q u .

[0023] Figure 5 Fig. 5 is a simulation result of the influence of the double-ridge depth h u of the dielectric waveguide resonator of the application on the first three modes: (a) resonant frequency and (b) unloaded quality factor Q u .

[0024] Figure 6 Fig. 6 is a three-dimensional structural diagram of the four-order rectangular double-ridge double-mode double-passband dielectric waveguide filter of the application.

[0025] Figure 7 Fig. 7 is a top view of the four-order rectangular double-ridge double-mode double-passband dielectric waveguide filter of the application.

[0026] Figure 8 Fig. 8 is a coupling topology structure diagram of the four-order rectangular double-ridge double-mode double-passband dielectric waveguide filter of the application.

[0027] Figure 9is the S-parameter simulation result of the invented four-order rectangular double-ridge dual-mode dual-passband dielectric waveguide filter.

[0028] Figure 10 is the frequency versus frequency-adjusting blind hole depth of the invented four-order rectangular double-ridge dual-mode dual-passband dielectric waveguide filter h 1. (a) low frequency; (b) high frequency.

[0029] Figure 11 is the frequency versus double-ridge depth of the invented four-order rectangular double-ridge dual-mode dual-passband dielectric waveguide filter h u . (a) low frequency; (b) high frequency.

[0030] Figure 12 is the low-frequency coupling coefficient between the first dielectric waveguide resonator DR1 and the second dielectric waveguide resonator DR2 in the invented filter k 12 , the high-frequency coupling coefficient k 56 versus the parameter: (a) the first coupling window length (the interval of the vertical through holes of the first coupling membrane) l c1 ; (b) the first coupling slot depth h c1 .

[0031] Figure 13 is the low-frequency coupling coefficient between the second dielectric waveguide resonator DR2 and the third dielectric waveguide resonator DR3 in the invented filter k 23 , the high-frequency coupling coefficient k 67 versus the parameter: (a) the second coupling window length (the interval of the vertical through holes of the second coupling membrane) l c2 ; (b) the second coupling slot depth h c2 ; (c) the first coupling blind hole depth h m1 .

[0032] Figure 14 is the external quality factor of the invented filter Q e versus the length of the center of the feeding probe to the center of the resonator l p1 .

[0033] Figure 15 is the external quality factor of the invented filter Q e versus the depth of the feeding probe h p1 . DETAILED DESCRIPTION

[0034] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Example

[0035] like Figure 1 As shown, the miniaturized double-ridged dual-mode dielectric waveguide resonator of this embodiment has a three-dimensional structure as shown in FIG. Figure 1 As shown, it includes a rectangular dielectric waveguide resonator with a metallized (silver-plated) surface. A frequency adjustment blind hole C is provided on the upper surface of the rectangular dielectric waveguide resonator. An upper ridge A with a rectangular cross-section is formed on the upper surface of the dielectric waveguide resonator, and a lower ridge B with a rectangular cross-section is formed on the lower surface. The upper ridge A and the lower ridge B are parallel (specifically, both the upper ridge A and the lower ridge B are arranged parallel to the X-axis) and are respectively located on the left and right sides of the frequency adjustment blind hole C.

[0036] like Figure 2 The figure shows the electric field distribution of the first two modes of the rectangular ridgeless dielectric waveguide resonator. 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 installation of coaxial connectors for feeding.

[0037] 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 frequency of the mode and quasi-TEM mode is smaller, while the quasi-TM 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-TM120 The resonance frequency of the mode is greatly reduced, and the unloaded quality factor of the mode is also reduced. As can be seen from the above, the depth of the frequency adjustment blind hole and the depth of the double ridge in the resonator can control the resonance frequency and the quality factor of the first three modes, and the unloaded quality factor of the resonator adopted by the present application can be maintained above 1390. The main mode of the resonator is quasi-TM 110 The resonance frequency of the second high-order mode quasi-TEM mode is independently adjusted by the depth of the frequency adjustment blind hole C, and the resonance frequency of the first high-order mode quasi-TM 120 The resonance frequency of the mode is greatly reduced, and the unloaded quality factor of the mode is also reduced. As can be seen from the above, the depth of the frequency adjustment blind hole and the depth of the double ridge in the resonator can control the resonance frequency and the quality factor of the first three modes, and the unloaded quality factor of the resonator adopted by the present application can be maintained above 1390. The main mode of the resonator is quasi-TM Embodiment

[0038] The present embodiment discloses a miniaturized four-order dielectric waveguide dual-passband filter based on a rectangular double-ridge dual-mode resonator, which has a three-dimensional structure as shown in Figure 6 , and a top view as shown in Figure 7 , comprising a dielectric block, an input end coaxial connector 1 and an output end coaxial connector 6. The coupling topology structure of the filter is shown in Figure 8 .

[0039] The dielectric block can be fired from dielectric ceramic material, and the outer surface thereof is silver-plated to be metallized except for the first unmetallized circular ring 2 and the second unmetallized circular ring 5. The dielectric block comprises four sequentially coupled rectangular double-ridge dielectric waveguide resonators of the embodiment one, as shown in Figure 6 、 Figure 8 , which are respectively a first dielectric waveguide resonator DR1, a second dielectric waveguide resonator DR2, a third dielectric waveguide resonator DR3 and a fourth dielectric waveguide resonator DR4 from the input end to the output end. The first dielectric waveguide resonator DR1 is provided with a first frequency adjustment blind hole C1 at the center of the upper surface thereof, which has a depth of h 1 and a diameter of r 1. The second dielectric waveguide resonator DR2 is provided with a second frequency adjustment blind hole C2 at the center of the upper surface thereof, which has a depth of h 1 and a diameter of r 2. The third dielectric waveguide resonator DR3 is provided with a third frequency adjustment blind hole C3 at the center of the upper surface thereof, which has a depth of h 1 and a diameter of r 2. The fourth dielectric waveguide resonator DR4 is provided with a fourth frequency adjustment blind hole C4 at the center of the upper surface thereof, which has a depth of h 1 and a diameter of r 3.

[0040] The adjacent resonators are coupled through coupling diaphragms. Specifically, as shown in Figure 6As shown, the first dielectric waveguide resonator DR1 and the second dielectric waveguide resonator DR2 are coupled to each other via a first coupling diaphragm 7, the second dielectric waveguide resonator DR2 and the third dielectric waveguide resonator DR3 are coupled to each other via a second coupling diaphragm 8, and the third dielectric waveguide resonator DR3 and the fourth dielectric waveguide resonator DR4 are coupled to each other via a third coupling diaphragm 9. Energy is sequentially coupled to the next-stage resonator via the coupling diaphragms. 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 pass through. The full-length upper ridge A and lower ridge B can be formed on the dielectric block at one time, making its processing more convenient.

[0041] The lower surface of the first dielectric waveguide resonator DR1 is provided with an input-end metalized blind hole 3 located below the upper ridge A, and the lower surface of the fourth dielectric waveguide resonator DR4 is provided with an output-end metalized blind hole 4 located below the upper ridge A. Both blind holes are not located in the exact center and have the same height. In this example, the first unmetalized ring 2 is connected to the input-end metalized blind hole 3, and the second unmetalized ring 5 is connected to the output-end metalized blind hole 4. The inner conductor of the input-end coaxial connector 1 is connected to the input feeding 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 feeding probe P2, and the outer conductor is connected to the surface metal layer of the fourth dielectric waveguide resonator DR4. The input feeding probe P1 and the output feeding probe P2 are respectively embedded in the input-end metalized blind hole 3 and the output-end metalized blind hole 4 for feeding. The input port coupling strength is adjusted by adjusting the insertion depth of the input feed probe P1 , and the output port coupling strength is adjusted by adjusting the insertion depth of the output feed probe P2 .

[0042] like Figure 6 、 Figure 7 As shown, the first coupling diaphragm 7, the second coupling diaphragm 8, and the third coupling diaphragm 9 are each 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 of the same coupling diaphragm. Figure 7 As shown, the coupling window length of the first coupling diaphragm 7 and the third coupling diaphragm 9 is l c1 , the coupling window length of the second coupling diaphragm 8 is l c2 . w 1. w 2 and w3 are the widths of the coupling membranes. The first coupling membrane 7 is provided with a first coupling groove 10 on the lower surface, which is communicated with the lower ridge B. The second coupling membrane 8 is provided with a second coupling groove 11 on the lower surface, which is communicated with the lower ridge B. The third coupling membrane 9 is provided with a third coupling groove 12 on the lower surface, which is communicated with the lower ridge B. h c1 、 h c2 and h c3 are the depths of the coupling grooves. Experiments show that the low-frequency coupling coefficient between adjacent resonators can be independently adjusted by the spacing (length of the coupling window) of the two through-holes of the first, second and third coupling membranes, and the high-frequency coupling coefficient between adjacent resonators can be independently adjusted by the depths of the first, second and third coupling grooves.

[0043] As Figure 6 described in the embodiment, the second coupling membrane 8 is provided with a first coupling adjustment blind hole 13 on the upper surface for fine adjustment of the high-frequency coupling coefficient between the second dielectric waveguide resonator DR2 and the third dielectric waveguide resonator DR3, the depth of the first coupling adjustment blind hole 13 is h m1 , and the diameter is r m1 ; the third coupling membrane 9 is provided with a second coupling adjustment blind hole 14 on the upper surface for fine adjustment of the high-frequency coupling coefficient between the third dielectric waveguide resonator DR3 and the fourth dielectric waveguide resonator DR4, the depth of the second coupling adjustment blind hole 14 is h m2 , and the diameter is r m1 . The outer ring diameter at the input coaxial connector 1 and the output coaxial connector 6 is w out 2.6 times the inner ring diameter w in , which is used to ensure 50Ω port matching.

[0044] The working process of the four-order filter is described as follows:

[0045] The signal is input from the input coaxial connector 1, fed into the first dielectric waveguide resonator DR1 through the input feed probe P1 and the input metallized blind hole 3, coupled through the first coupling membrane 7 to realize source load coupling, then sequentially passes through the second dielectric waveguide resonator DR2, the second coupling membrane 8, the third dielectric waveguide resonator DR3, the third coupling membrane 9, and is coupled to the fourth dielectric waveguide resonator DR4, and is output from the output coaxial connector 6 after passing through the output metallized blind hole 4 and the output feed probe P2.

[0046] The parameters of the filter of the embodiment of the application are shown in the following table:

[0047] Parameter w all ]]> ​ h 1]]> ​ r 1]]> ​ r 2]]> ​ r 3]]> ​ w cr ]]> ​ Value (mm) 63.43 14.8 8.2 2.43 2.8 2.4 2.78 3.2 Parameter r m1 ]]> ​ h m1 ]]> ​ h m2 ]]> ​ h c1 ]]> ​ h c2 ]]> ​ h c3 ]]> ​ w in ]]> ​ w out ]]> ​ Value (mm) 2 2.4 1 2.8 4.3 3.12 1.5 4 Parameter <![CDATA[ w 1]]> w 2]]> ​ w 3]]> ​ l c1 ]]> ​ l c2 ]]> ​ l p1 ]]> ​ h p1 ]]> ​ w u ]]> ​ Value (mm) 1.12 1.83 1.08 3.32 3.81 2.82 3 1.5 Parameter w b ]]> ​ h u ]]> ​ h b ]]> ​ Value (mm) 1.5 3.96 3.96

[0048] Table, w all Total width of the dual-passband filter, l Length of the dual-passband filter, h Thickness of the dual-passband filter, h 1 is the depth of the first frequency adjustment blind hole C1, the second frequency adjustment blind hole C2, the third frequency adjustment blind hole C3, the fourth frequency adjustment blind hole C4, r 1 is the diameter of the first frequency adjustment blind hole C1, r 2 is the diameter of the second frequency adjustment blind hole C2, the third frequency adjustment blind hole C3, r 3 is the diameter of the fourth frequency adjustment blind hole C4, w cr Outer ring diameter of the first unmetallized circular ring 2 and the second unmetallized circular ring 5, r m1 Diameter of the first coupling adjustment blind hole 13 and the second coupling adjustment blind hole 14, h m1 Depth of the first coupling adjustment blind hole 13, h m2 Depth of the second coupling adjustment blind hole 14, h c1 Depth of the first coupling groove, h c2 Depth of the second coupling groove, h c3 Depth of the third coupling groove, w in Inner ring diameter of the input end coaxial connector 1 and the output end coaxial connector 6, which is also the inner ring diameter of the first unmetallized circular ring 2 and the second unmetallized circular ring 5, w out Outer ring diameter of the input end coaxial connector 1 and the output end 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 Coupling window length of the first coupling diaphragm 7 and the third coupling diaphragm 9, l c2 Coupling window length of the second coupling diaphragm 8, l p1 Distance from the center of the feed probe to the center of the resonator, h p1 Depth of the feed probe, w u Width of the upper ridge A, w b 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.

[0049] 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. Figure 9 As shown in the figure, the filter's passbands are 2570-2650MHz for the low frequency and 3400-3500MHz for the high frequency, covering both the 2570-2620MHz band for the n38 and the 3400-3500MHz band for the n78. The low frequency center frequency is 2615MHz, with a maximum insertion loss of 0.46dB, an operating bandwidth of 80MHz, and a relative bandwidth of 3%. The high frequency center frequency is 3450MHz, with a maximum insertion loss of 0.46dB, an operating bandwidth of 100MHz, and a relative bandwidth of 2.9%. Harmonics occur at 4150MHz.

[0050] To further illustrate the filter's dual-mode independent controllable capability, Figure 8 The coupled topology of dual-passband filter is given. Figure 10 Shows that as the depth of the resonator blind hole increases h 1 increases, the low-frequency passband of the filter moves toward the lower frequency as a whole, while the high-frequency passband remains basically unchanged; Figure 11 It shows that the resonator double ridge depth 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. Figure 10 and Figure 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.

[0051] Figure 12-13 The curves of 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 curve changes. 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 56is the coupling coefficient between the first dielectric waveguide resonator DR1 and the second dielectric waveguide resonator DR2 in quasi-TM mode at high frequency, and is given by 120 Figure 12 It is known that, as the distance length (the coupling window length of the second coupling diaphragm) between the two through holes increases, l c1 the coupling coefficient k 12 obviously increases, k 56 and basically remains unchanged; as the depth of the first coupling groove 10 on the lower surface of the coupling window increases, h c1 k 12 and k 56 decrease. Similarly, k 23 is the coupling coefficient between the second dielectric waveguide resonator DR2 and the third dielectric waveguide resonator DR3 in quasi-TM mode at low frequency, 110 k 67 is the coupling coefficient between the second dielectric waveguide resonator DR2 and the third dielectric waveguide resonator DR3 in quasi-TM mode at high frequency, and is given by 120 Figure 13 It is known that, as the distance length (the coupling window length of the second coupling diaphragm) between the two through holes increases, l c2 k 23 the coupling coefficient k 67 obviously increases, h c2 k 67 decreases, k 23 only changes slightly; as the depth of the first coupling adjustment blind hole 13 on the upper surface of the coupling window increases, h m1 k 23 and k 67 increase.

[0052] In theory, when the coupling coefficient between the resonators changes, the corresponding external quality factor will also change. Figure 14-15 are the change curves of the filter external quality factor with the position of the feed probe l p1 , the depth of the probe h p1 . As the position of the feed probe l ​​​​​​​p1 increase, quasi-TM 120 mode of Q e decrease, quasi-TM 110 mode of Q e. slow increase; feed probe depth h p1 will let Q e decrease. Comprehensive Figure 12-15 , it shows that the dual-band dielectric waveguide filter is able to independently control the dual mode.

[0053] The four-order dual-mode dual-band dielectric waveguide filter utilizes two rectangular ridges to independently control the dual mode in the case of reducing the filter volume, reduces the manufacturing cost, has low insertion loss, and has high practicability.

[0054] The simulation results are computer simulation results.

[0055] In addition to the above-mentioned embodiments, the present application can have other implementation manners. Any technical solution formed by equivalent replacement or equivalent transformation falls within the protection scope required by the present application.

Claims

1. A miniaturized dual-ridge dual-mode dielectric waveguide resonator, comprising a surface-metallized dielectric waveguide resonator, wherein a frequency adjustment blind hole (C) is provided on the upper surface of the dielectric waveguide resonator, an upper ridge (A) with a rectangular cross section is provided on the upper surface of the dielectric waveguide resonator, and a lower ridge (B) with a rectangular cross section is provided on the lower surface of the dielectric waveguide resonator, wherein the upper ridge (A) and the lower ridge (B) are parallel and respectively provided on the left and right sides of the frequency adjustment blind hole (C); the dielectric waveguide resonator has a main mode quasi-TM 110 Mode, first higher 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, and is used to adjust the main mode quasi-TM 110 The resonance frequencies of the first high-order quasi-TEM mode and the second high-order quasi-TEM mode are shown in Figure 2. The upper ridge (A) and the lower ridge (B) are located at the first high-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.

2. The miniaturized double-ridged dual-mode dielectric waveguide resonator according to claim 1, 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).

3. The miniaturized double-ridged dual-mode dielectric waveguide resonator according to claim 1, wherein: The Master Mode™ 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 tuned independently by the depths of the upper (A) and lower (B) ridges.

4. A miniaturized fourth-order double-ridged dual-mode dielectric waveguide dual-passband filter having a surface metallized dielectric block, characterized by: 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 pass through. The lower surface of the first dielectric waveguide resonator (DR1) is provided with an input-end metallized blind hole (3) located below the upper ridge (A). The lower surface of the fourth dielectric waveguide resonator (DR4) is provided with an output-end metallized blind hole (4) located below the upper ridge (A). An input feeding probe (P1) and an output feeding probe (P2) are respectively embedded in the input-end metallized blind hole (3) and the output-end metallized blind hole (4) for feeding.

5. The miniaturized fourth-order double-ridged dual-mode dielectric waveguide dual-passband filter according to claim 4, 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 feeding probe (P1), and 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 feeding probe (P2), and 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 input port coupling strength is adjusted by adjusting the insertion depth of the input feeding probe (P1), and the output port coupling strength is adjusted by adjusting the insertion depth of the output feeding probe (P2).

6. The miniaturized fourth-order double-ridged dual-mode dielectric waveguide dual-passband filter according to claim 4, 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 a 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).

7. The miniaturized fourth-order double-ridged dual-mode dielectric waveguide dual-passband filter according to claim 6, characterized in that: A first coupling adjustment blind hole (13) for fine-tuning the high-frequency coupling coefficient between the second dielectric waveguide resonator (DR2) and the third dielectric waveguide resonator (DR3) is provided on the upper surface of the second coupling diaphragm (8); and 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) is provided on the upper surface of the third coupling diaphragm (9).

8. The miniaturized fourth-order double-ridged dual-mode dielectric waveguide dual-passband filter according to claim 6, characterized in that: The distance between the two vertical through holes of the first coupling diaphragm (7) is equal to the distance between the two vertical through holes of the third coupling diaphragm (9).

9. The miniaturized fourth-order double-ridged dual-mode dielectric waveguide dual-passband filter according to any one of claims 4 to 7, 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 (DR2), 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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