A dielectric filter and communication device

Abstract

This application provides a dielectric filter and a communication device. The dielectric filter includes a dielectric entity, which has at least a first resonant blind aperture located on a first side and a second resonant blind aperture located on a second side. The first resonant blind aperture and the dielectric entity surrounding it form a first resonator, and the second resonant blind aperture and the dielectric entity surrounding it form a second resonator. A first coupling via and a second coupling via are formed on the top surface of the dielectric entity, and a first connection portion is provided between the first coupling via and the second coupling via. The first resonator and the second resonator are negatively coupled through the first connection portion. This design can reduce the on-board area of ​​the dielectric filter without reducing the Q value of the resonator's single cavity, effectively achieving miniaturization of the dielectric filter. Furthermore, it can improve far-end suppression and reduce the loss of the dielectric filter.

Description

[0001] This application claims priority to Chinese Patent Application No. 202310677885.8, filed on June 8, 2023, entitled "A Medium Filter and Communication Device", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of communication technology, and in particular to a dielectric filter and a communication device. Background Technology

[0003] A dielectric filter is a filtering device formed by the coupling between dielectric resonators. Dielectric filters are widely used in communication devices such as communication base stations, satellite communications, and navigation systems. They can filter out signals outside the passband frequency while allowing signals within the passband frequency to pass through, thus obtaining a signal of a specified frequency and effectively filtering out interference signals.

[0004] In related technologies, a dielectric filter is provided, comprising a dielectric entity. Multiple resonant blind holes are formed on the upper surface of the dielectric entity. Each resonant blind hole and its surrounding dielectric entity can form a resonator of the filter. Signal energy can be converted between electric and magnetic fields between adjacent resonators to achieve coupling between them. Typically, a coupling blind hole is also formed between adjacent resonant blind holes. The depth of the coupling blind hole is greater than the depth of the resonant blind holes, and the coupling blind hole is used to achieve negative coupling between the two resonators.

[0005] However, the single-cavity Q value of a dielectric filter is directly proportional to the projection size of the dielectric entity onto the resonant blind hole along the axis. In the dielectric filter described above, the resonant blind hole is located on the upper surface of the dielectric entity, which makes the area occupied by the dielectric filter when it is mounted on the mounting plate (i.e., the on-board area) larger. Reducing the on-board area of ​​the dielectric filter will reduce the single-cavity Q value of the dielectric filter, which is not conducive to the miniaturization design of the dielectric filter. Summary of the Invention

[0006] This application provides a dielectric filter and a communication device that can reduce the on-board area of ​​the dielectric filter without reducing the Q value of a single cavity of the resonator, thus effectively realizing the miniaturization design of the dielectric filter.

[0007] A first aspect of this application provides a dielectric filter, including a dielectric entity having opposing first and second sides and a top surface located between the first and second sides;

[0008] At least one set of resonant blind holes are formed on the dielectric entity, and the at least one set of resonant blind holes includes a first set of resonant blind holes, which includes a first resonant blind hole and a second resonant blind hole.

[0009] The first resonant blind aperture is located on the first side, and the second resonant blind aperture is located on the second side;

[0010] The first resonant blind hole and the dielectric material surrounding it form a first resonator, and the second resonant blind hole and the dielectric material surrounding it form a second resonator.

[0011] The top surface of the dielectric entity is provided with a first coupling through hole and a second coupling through hole, and a first connection portion is provided between the first coupling through hole and the second coupling through hole. The first resonator and the second resonator are negatively coupled through the first connection portion.

[0012] By placing the first and second resonant blind holes on the side surface of the dielectric entity, and by creating the first and second coupling vias on the top surface of the dielectric entity, negative coupling between the first and second resonators is achieved. Reducing the projected area of ​​the dielectric entity in the height direction (i.e., from the upper surface to the lower surface) does not affect the projected area of ​​the dielectric entity 110 in the axial direction of the resonant blind holes (the first and second resonant blind holes). This reduces the on-board area of ​​the dielectric filter by decreasing the projected area of ​​the dielectric entity in the height direction, effectively miniaturizing the dielectric filter without reducing the Q value of a single resonator cavity.

[0013] In one possible implementation, the at least one set of resonant blind holes further includes a second set of resonant blind holes, the second set of resonant blind holes including a third resonant blind hole and a fourth resonant blind hole;

[0014] The third resonant blind hole is located on the first side, and the fourth resonant blind hole is located on the second side;

[0015] The third resonant blind hole and the dielectric material around it form a third resonator, and the fourth resonant blind hole and the dielectric material around it form a fourth resonator.

[0016] A third coupling through hole is provided on the top surface of the dielectric entity, and two second connecting parts are provided on both sides of the third coupling through hole. The third resonator and the fourth resonator are positively coupled through the two second connecting parts.

[0017] In one possible implementation, a first coupling groove is further formed on the top surface of the medium entity, and both the first coupling through hole and the second coupling through hole are formed on the bottom wall of the first coupling groove.

[0018] The first coupling slot can adjust the size of the coupling channel between the first resonator and the second resonator, thereby changing the amount of coupling between the first resonator and the second resonator.

[0019] In one possible implementation, a second coupling groove is further formed on the top surface of the medium entity, and the third coupling through hole is formed on the bottom wall of the second coupling groove.

[0020] The second coupling slot can adjust the size of the coupling channel between the third and fourth resonators, thereby changing the coupling amount between the third and fourth resonators and enabling more types of coupling between them.

[0021] In one possible implementation, a third coupling groove is further formed on the top surface of the medium entity, and the first coupling through hole, the second coupling through hole and the third coupling through hole are all formed on the bottom wall of the third coupling groove.

[0022] In one possible implementation, a fourth coupling groove is further formed on the top surface of the medium entity, and both the first coupling through hole and the third coupling through hole are formed on the bottom wall of the fourth coupling groove.

[0023] In one possible implementation, a fourth coupling via is also provided on the medium entity;

[0024] The fourth coupling via is located through the first side or the second side of the dielectric entity, and the fourth coupling via is located between two adjacent sets of resonant blind vias.

[0025] In one possible implementation, a fifth coupling groove is also formed on the top surface of the dielectric entity; the fifth coupling groove extends from the first side surface of the dielectric entity to the second side surface, and the fifth coupling through hole is located between two adjacent sets of resonant blind holes.

[0026] The fifth coupling slot can also adjust the size of the coupling channel between the first and third resonators and between the second and fourth resonators, so that different coupling amounts can be achieved between two adjacent resonators.

[0027] In one possible implementation, a fifth coupling via is also provided on the top surface of the dielectric entity; the fifth coupling via is located between two adjacent sets of resonant blind vias.

[0028] The fifth coupling via can further adjust the size of the coupling channel between the first and third resonators, as well as between the second and fourth resonators, so that different coupling amounts can be achieved between two adjacent resonators.

[0029] In one possible implementation, the number of the first group of resonant blind holes and the second group of resonant blind holes is multiple; the multiple first group of resonant blind holes and the multiple second group of resonant blind holes are arranged alternately.

[0030] In one possible implementation, the first resonant blind hole and the second resonant blind hole in the first set of resonant blind holes are coaxially arranged;

[0031] The third and fourth resonant blind holes in the second group of resonant blind holes are coaxially arranged.

[0032] This improves the overall structural regularity of the dielectric filter, facilitating its design and production. Furthermore, during simulation calculations, it makes it easier to determine the dimensions of each resonant blind aperture, thus improving operational efficiency.

[0033] In one possible implementation, the dielectric filter further includes a conductive layer that covers the surface of the dielectric entity.

[0034] In one possible implementation, the dielectric filter further includes a signal input terminal;

[0035] The signal input terminal is connected to the signal of the first resonator.

[0036] In one possible implementation, a first coupling blind hole is also provided on the medium entity;

[0037] One end of the first coupling blind hole is connected to the signal input terminal, and the other end of the first coupling blind hole is connected to the first resonant blind hole.

[0038] In one possible implementation, a sixth coupling groove is also provided on the medium entity;

[0039] One end of the sixth coupling groove is connected to the other end of the first coupling blind hole, and the other end of the sixth coupling groove is connected to the first resonant blind hole.

[0040] In one possible implementation, the dielectric filter further includes a signal output terminal;

[0041] The signal input terminal is connected to the signal of the second resonator.

[0042] A second aspect of this application provides a communication device including any of the media filters described above.

[0043] In one possible implementation, the communication device further includes an antenna that is signal-connected to the dielectric filter. Attached Figure Description

[0044] Figure 1 This is a schematic diagram of the structure of a dielectric filter provided in related technologies;

[0045] Figure 2 This is a top view of a dielectric filter provided in related technologies;

[0046] Figure 3 This is a schematic diagram of the structure of a dielectric filter from one perspective, provided as an embodiment of this application.

[0047] Figure 4 This is a schematic diagram of the structure of a dielectric filter provided in an embodiment of this application from another perspective;

[0048] Figure 5 A top view of a dielectric filter provided in an embodiment of this application;

[0049] Figure 6 A cross-sectional view of a dielectric filter provided in an embodiment of this application;

[0050] Figure 7 This is a schematic diagram of another dielectric filter structure provided in an embodiment of this application;

[0051] Figure 8 A top view of another dielectric filter provided in an embodiment of this application;

[0052] Figure 9 This is a schematic diagram of a signal input terminal configuration provided in an embodiment of this application;

[0053] Figure 10 This is a diagram showing the signal return efficiency of dielectric filters in related technologies.

[0054] Figure 11 This is a signal return efficiency diagram of a dielectric filter provided in an embodiment of this application.

[0055] Explanation of reference numerals in the attached figures:

[0056] 100 - Dielectric filter; 110 - Dielectric entity; 111 - First side surface;

[0057] 112 - Second side surface; 120 - First group of resonant blind holes; 121 - First resonant blind hole;

[0058] 122 - Second resonant blind aperture; 123 - First resonator; 124 - Second resonator;

[0059] 130 - Second group of resonant blind holes; 131 - Third resonant blind hole; 132 - Fourth resonant blind hole;

[0060] 133 - Third resonator; 134 - Fourth resonator; 140 - First coupling via;

[0061] 141 - Second coupling through hole; 142 - First connecting part; 143 - Third coupling through hole;

[0062] 144 - Second connecting part; 145 - First coupling groove; 146 - Second coupling groove;

[0063] 147 - Third coupling groove; 148 - Fourth coupling groove; 149 - Fourth coupling through hole;

[0064] 150 - Fifth coupling slot; 151 - Fifth coupling through hole; 160 - Signal input terminal;

[0065] 161 - First coupling blind hole; 162 - Sixth coupling groove. Detailed Implementation

[0066] The terminology used in the implementation section of this application is for the purpose of explaining specific embodiments of this application only, and is not intended to limit this application.

[0067] A dielectric filter is a filtering device formed by the coupling between dielectric resonators. Dielectric filters are widely used in communication devices such as communication base stations, satellite communications, and navigation systems. They can filter out signals outside the passband frequency while allowing signals within the passband frequency to pass through, thus obtaining a signal of a specified frequency and effectively filtering out interference signals.

[0068] Figure 1 This is a schematic diagram of the structure of a dielectric filter provided in related technologies. Figure 2 This is a top view of a dielectric filter provided in related technologies.

[0069] In related technologies, see Figure 1 and Figure 2 As shown, a dielectric filter 1 is provided, which includes a dielectric body 11. Multiple resonant blind holes are formed on the upper surface of the dielectric body 11. For example, it may include a first resonant blind hole 12 and a second resonant blind hole 13. Each resonant blind hole and its surrounding dielectric body can form a resonator of the dielectric filter. Signals can undergo energy conversion between electric and magnetic fields between two adjacent resonators to achieve coupling between the two resonators. A coupling blind hole is also formed between two adjacent resonant blind holes, for example, see [reference needed]. Figure 1 and Figure 2As shown, a first coupling blind hole 14 (also called a negative coupling deep hole) can be opened between the first resonant blind hole 12 and the second resonant blind hole 13. The depth of the first coupling blind hole 14 is greater than the depth of the first resonant blind hole 12 and the second resonant blind hole 13. The first coupling blind hole 14 is used to realize the negative coupling between the resonator formed by the first resonant blind hole 12 and the resonator formed by the second resonant blind hole 13.

[0070] Generally, the Q-value of a dielectric filter is directly proportional to the projection of the dielectric material onto the resonant blind aperture along its axis. That is, the larger the projected area of ​​the dielectric material onto the resonant blind aperture, the larger the Q-value of the dielectric filter, and vice versa. The Q-value of a dielectric filter affects its filtering efficiency; a larger Q-value results in lower filtering loss, and vice versa.

[0071] However, in the above structure, the coupling blind via occupies the area of ​​the upper surface of the dielectric entity, resulting in a larger area occupied by the dielectric filter when mounted on the mounting plate (i.e., the on-board area), which is not conducive to the miniaturization design of the dielectric filter. If the on-board area of ​​the dielectric filter is reduced by reducing the volume of the dielectric filter, the projected area of ​​the dielectric entity in the axial direction of the resonant blind via (e.g., the first resonant blind via 12 and the second resonant blind via 13) will be reduced accordingly. This will reduce the Q value of the resonator and increase the loss of the dielectric filter.

[0072] Furthermore, the first coupling blind aperture 14 in the aforementioned dielectric filter reduces the far-end suppression capability of the dielectric filter, thus decreasing its out-of-band suppression effect. Therefore, during use, the aforementioned dielectric filter typically requires the use of a low-pass trace to suppress out-of-band electromagnetic signals. However, the low-pass trace has insertion loss, which increases the loss of the dielectric filter.

[0073] To address the aforementioned issues, researchers devised an improvement to the structure of the dielectric filter. This was achieved by placing the first and second resonant blind holes on the two sides of the dielectric entity, and by creating a first and second coupling via on the top surface of the dielectric entity. A first connection portion exists between the first and second coupling vias, allowing the first and second resonators to achieve negative coupling. Reducing the projected area of ​​the dielectric entity in the height direction (i.e., from the upper to the lower surface) does not affect the projected area of ​​the dielectric entity 110 in the axial direction of the resonant blind holes (the first and second resonant blind holes). This reduces the on-board area of ​​the dielectric filter by decreasing the projected area of ​​the dielectric entity in the height direction, effectively miniaturizing the dielectric filter without reducing the Q-value of the resonator's single cavity.

[0074] The dielectric filter provided in the embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0075] Figure 3 This is a schematic diagram of the structure of a dielectric filter from one perspective, provided in an embodiment of this application. Figure 4 This is a schematic diagram of the structure of a dielectric filter provided in an embodiment of this application from another perspective. Figure 5 This is a top view of a dielectric filter provided in an embodiment of this application. Figure 6 This is a cross-sectional view of a dielectric filter provided in an embodiment of this application.

[0076] This application provides a dielectric filter 100, see [link to relevant documentation] Figure 3 and Figure 4 As shown, the dielectric filter 100 may include a dielectric entity 110. For example, the dielectric entity 110 may be made of ceramic. The dielectric entity 110 may be integrally formed by injection molding, which can improve the stability and reliability of the dielectric entity 110 structure. The dielectric entity 110 has opposing first side surfaces 111 and second side surfaces 112, and a top surface 113 located between the first side surfaces 111 and the second side surfaces 112.

[0077] At least one set of resonant blind vias can be formed on the dielectric entity 110. For example, at least one set of resonant blind vias may include a first set of resonant blind vias 120, the first set of resonant blind vias 120 (refer to...) Figure 6 The device (as shown) may include a first resonant blind aperture 121 and a second resonant blind aperture 122. The first resonant blind aperture 121 may be located on a first side surface 111, and the second resonant blind aperture 122 may be located on a second side surface 112. The first resonant blind aperture 121 and its surrounding dielectric material 110 may form a first resonator 123, and the second resonant blind aperture 122 and its surrounding dielectric material 110 may form a second resonator 124.

[0078] See Figure 5 and Figure 6 As shown, a first coupling through-hole 140 and a second coupling through-hole 141 can be formed on the top surface 113 of the dielectric entity 110. For example, the first coupling through-hole 140 and the second coupling through-hole 141 can extend from the top surface 113 of the dielectric entity 110 to the bottom surface of the dielectric entity 110. A first connecting portion 142 can be provided between the first coupling through-hole 140 and the second coupling through-hole 141, and negative coupling is achieved between the first resonator 123 and the second resonator 124.

[0079] For example, the first coupling via 140 and the second coupling via 141 can be located near the sides of the first resonator 123 and the second resonator 124, so that the first connecting portion 142 can be located near the middle of the first resonator 123 and the second resonator 124. The dielectric material 110 at the corresponding positions of the first coupling via 140 and the second coupling via 141 can be removed, leaving the first connecting portion 142 between them, allowing the first resonator 123 and the second resonator 124 to be connected through the dielectric material 110 corresponding to the first connecting portion 142. Electromagnetic wave signals can propagate from the first resonator 123 to the second resonator 124 through the first connecting portion 142, achieving negative coupling between the first resonator 123 and the second resonator 124.

[0080] For example, the dielectric filter 100 may further include a conductive layer (not shown in the figure), which may cover the surface of the dielectric entity 110. For example, the conductive layer may be provided on the first side 111, the second side 112, the top surface 113, the bottom surface of the dielectric entity 110, as well as the inner walls of the first resonant blind hole 121, the second resonant blind hole 122, the first coupling via 140, and the second coupling via 141. The dielectric filter 100 can be understood as the conductive layer forming a closed cavity, in which the dielectric entity 110 is filled.

[0081] For example, after the dielectric entity 110 is formed, a metal layer can be applied to the surface of the dielectric entity 110 by spraying or brushing to form a conductive layer. For example, the material of the conductive layer can be silver.

[0082] During operation, electromagnetic wave signals can enter the dielectric filter 100 through its signal input port and propagate within the dielectric entity 110. They can propagate from one resonator to an adjacent resonator; for example, the electromagnetic wave signal can propagate from the first resonator 123 to the second resonator 124 through the first connection 142 between the first coupling via 140 and the second coupling via 141. An electric field exists near the center of the resonator, while a magnetic field exists near the edge of the resonator, i.e., near the conductive layer. The continuous exchange of energy between the electric and magnetic fields causes the dielectric filter 100 to generate electromagnetic resonance at certain similar frequencies. At the resonance point, energy can be transferred from the input to the output of the dielectric filter 100. The coupling of electric and magnetic fields between different resonators creates a passband, allowing only signals with frequencies within the passband to pass through, while signals of other frequencies cannot, thus achieving a filtering effect.

[0083] When an electromagnetic wave signal encounters the conductive layer covering the dielectric entity 110, it can be reflected by the conductive layer. After repeated reflections within the dielectric filter 100, a portion of the signal undergoes total reflection and is eventually output from the signal output terminal of the dielectric filter 100. The remaining portion of the signal cannot undergo total reflection within the dielectric entity 110 and returns to the signal input terminal, thus achieving the filtering out of that signal.

[0084] During the propagation of the electromagnetic wave signal from the first resonator 123 to the second resonator 124, negative coupling can be achieved between the first resonator 123 and the second resonator 124. Negative coupling, also known as electrical coupling, means that during the coupling process between the first resonator 123 and the second resonator 124, the conversion from electric field to magnetic field is dominant. In other words, during the coupling process between the first resonator 123 and the second resonator 124 through the first connection 142, the electric field dominates. Negative coupling can generate a transmission zero (see...). Figure 11 Point A in the diagram can enhance the suppression effect, improving the suppression performance of the dielectric filter 100 for a signal at a specific frequency, thus better suppressing the signal corresponding to that frequency. For example, if a high suppression requirement for a signal at a certain frequency is needed during the use of the dielectric filter 100, negative coupling can be set in the dielectric filter 100 to make the coupling of several resonators negative, thereby achieving stronger suppression of the signal at that frequency.

[0085] The size of the first connecting part 142 can affect the size of the coupling channel (also called window) between the first resonator 123 and the second resonator 124. The larger the cross-sectional area of ​​the first connecting part 142 in the direction from the first resonator 123 to the second resonator 124, the larger the coupling channel between the first resonator 123 and the second resonator 124 will be, and the signal bandwidth that the coupling channel can pass through will also be relatively larger. At this time, the coupling amount between the first resonator 123 and the second resonator 124 will be greater, and the greater the coupling amount, the wider the bandwidth.

[0086] Conversely, the smaller the cross-sectional area of ​​the first connecting part 142 in the direction from the first resonator 123 to the second resonator 124, the smaller the coupling channel between the first resonator 123 and the second resonator 124, and the smaller the signal bandwidth that the coupling channel can pass through. At this time, the coupling amount between the first resonator 123 and the second resonator 124 is also smaller, and the smaller the coupling amount, the narrower the bandwidth.

[0087] Therefore, the size of the first connecting portion 142 can be changed by changing the size of the first coupling through hole 140, for example, by changing the cross-sectional area of ​​the first coupling through hole 140 in the direction from the first resonator 123 to the second resonator 124, thereby changing the amount of coupling between the first resonator 123 and the second resonator 124.

[0088] During installation, the bottom surface of the dielectric filter 100 can be mounted on a mounting plate. The area occupied by the dielectric filter 100 when mounted on the mounting plate can be understood as the on-board area of ​​the dielectric filter 100.

[0089] Compared to related technologies that use resonant blind holes and coupling blind holes on the upper surface of the dielectric entity to achieve negative coupling between two resonators, this embodiment of the application achieves negative coupling between the first resonator 123 and the second resonator 124 by forming the first resonant blind hole 121 and the second resonant blind hole 122 on the side of the dielectric entity 110, and forming the first coupling through hole 140 and the second coupling through hole 141 on the top surface 113 of the dielectric entity 110. When the projected area of ​​the dielectric entity 110 in the height direction (i.e., from the upper surface to the lower surface of the dielectric entity) is reduced, it does not affect the projected area of ​​the dielectric entity 110 in the axial direction of the resonant blind holes (first resonant blind hole 121 and second resonant blind hole 122). In this way, the on-board area of ​​the dielectric filter 100 can be reduced by reducing the projected area of ​​the dielectric entity 110 in the height direction. Without reducing the Q value of the single cavity of the resonator, the on-board area of ​​the dielectric filter 100 is reduced, effectively realizing the miniaturization design of the dielectric filter 100.

[0090] Furthermore, compared to dielectric filters in related technologies, the resonant blind holes (first resonant blind hole 121 and second resonant blind hole 122) of the dielectric filter 100 provided in this embodiment are all disposed on both sides of the dielectric entity 110, which can reduce crosstalk between the resonators. And the negative coupling deep hole (i.e., ...) is eliminated. Figure 1 The first coupling blind hole 14) design can effectively improve the far-end suppression capability of the dielectric filter 100 and effectively improve the out-of-band suppression effect. It can eliminate the need for low-pass routing and avoid the insertion loss caused by multiple low-pass routing, thereby effectively reducing the loss of the dielectric filter.

[0091] See also Figure 5 and Figure 6 As shown, the dielectric entity 110 may also include a second set of resonant blind holes 130. The second set of resonant blind holes 130 may include a third resonant blind hole 131 and a fourth resonant blind hole 132. The third resonant blind hole 131 and the dielectric entity 110 around it can form a third resonator 133, and the fourth resonant blind hole 132 and the dielectric entity 110 around it can form a fourth resonator 134.

[0092] A third coupling through-hole 143 can also be provided on the top surface 113 of the dielectric entity 110. The third coupling through-hole 143 has two second connecting parts 144 on both sides. The third resonator 133 and the fourth resonator 134 can be positively coupled through the two second connecting parts 144. Positive coupling, also known as magnetic coupling, means that the magnetic field is the main force in the coupling process between the third resonator 133 and the fourth resonator 134.

[0093] For example, the third coupling via 143 can be located near the center of the third resonator 133 and the fourth resonator 134 to remove the dielectric material 110 at the center between the third resonator 133 and the fourth resonator 134, while retaining the dielectric material 110 near the sides between the third resonator 133 and the fourth resonator 134 to form two second connection portions 144. The third resonator 133 and the fourth resonator 134 can be connected through the dielectric material 110 corresponding to the two second connection portions 144. This allows electromagnetic wave signals to propagate from the third resonator 133 to the fourth resonator 134 through the two second connection portions 144 near the sides, thereby achieving positive coupling between the third resonator 133 and the fourth resonator 134.

[0094] The size of the second connecting part 144 can affect the size of the coupling channel (also called window) between the third resonator 133 and the fourth resonator 134. The larger the cross-sectional area of ​​the second connecting part 144 in the direction from the third resonator 133 to the fourth resonator 134, the larger the coupling channel between the third resonator 133 and the fourth resonator 134 will be. At this time, the coupling amount between the third resonator 133 and the fourth resonator 134 will be greater.

[0095] Conversely, the smaller the cross-sectional area of ​​the second connecting portion 144 in the direction from the third resonator 133 to the fourth resonator 134, the smaller the coupling channel between the third resonator 133 and the fourth resonator 134. In this case, the coupling amount between the third resonator 133 and the fourth resonator 134 is also smaller. Therefore, the size of the second connecting portion 144 can be changed by altering the size of the third coupling through-hole 143, for example, by changing the cross-sectional area of ​​the third coupling through-hole 143 in the direction from the third resonator 133 to the fourth resonator 134, thereby changing the coupling amount between the third resonator 133 and the fourth resonator 134.

[0096] See also Figure 5As shown, in one possible implementation, a first coupling groove 145 may also be formed on the dielectric entity 110, and the first coupling through hole 140 and the second coupling through hole 141 may both be formed on the bottom wall of the first coupling groove 145. The first coupling groove 145 can remove the material of the dielectric entity 110 near the top surface 113 of the first connecting part 142 to further reduce the size of the first connecting part 142, thereby adjusting the size of the coupling channel between the first resonator 123 and the second resonator 124, and thus changing the coupling amount between the first resonator 123 and the second resonator 124.

[0097] For example, when the dimension of the first coupling groove 145 in the direction from the top surface 113 to the bottom surface of the dielectric entity 110 is large, that is, the depth of the first coupling groove 145 is deep, the cross-sectional area of ​​the first coupling groove 145 in the direction from the third resonator 133 to the fourth resonator 134 is also relatively large, so that the cross-sectional area of ​​the first connecting part 142 in the direction from the first resonator 123 to the second resonator 124 is small, which can reduce the coupling amount between the first resonator 123 and the second resonator 124.

[0098] Conversely, when the dimension of the first coupling groove 145 in the direction from the top surface 113 to the bottom surface of the dielectric entity 110 is small, that is, the depth of the first coupling groove 145 is small, the cross-sectional area of ​​the first coupling groove 145 in the direction from the first resonator 123 to the second resonator 124 is also relatively small, so that the cross-sectional area of ​​the first connecting part 142 in the direction from the first resonator 123 to the second resonator 124 is large, which can increase the coupling amount between the first resonator 123 and the first resonator 124.

[0099] See also Figure 5 As shown, in another possible implementation, a second coupling groove 146 can be formed on the top surface 113 of the dielectric entity 110, and a third coupling through hole 143 can be formed on the bottom wall of the second coupling groove 146. The second coupling groove 146 can remove the material of the dielectric entity 110 near the top surface 113 of the second connecting part 144 to further reduce the size of the second connecting part 144, thereby adjusting the size of the coupling channel between the third resonator 133 and the fourth resonator 134, thereby changing the coupling amount between the third resonator 133 and the fourth resonator 134, and enabling more forms of coupling between the third resonator 133 and the fourth resonator 134.

[0100] For example, when the dimension of the second coupling groove 146 in the direction from the top surface 113 to the bottom surface of the dielectric entity 110 is large, that is, the depth of the second coupling groove 146 is deep, the cross-sectional area of ​​the second coupling groove 146 in the direction from the third resonator 133 to the fourth resonator 134 is also relatively large, so that the cross-sectional area of ​​the second connecting part 144 in the direction from the third resonator 133 to the fourth resonator 134 is small, which can reduce the coupling amount between the third resonator 133 and the fourth resonator 134.

[0101] Conversely, when the dimension of the second coupling groove 146 in the direction from the top surface 113 to the bottom surface of the dielectric entity 110 is small, that is, the depth of the second coupling groove 146 is small, the cross-sectional area of ​​the second coupling groove 146 in the direction from the third resonator 133 to the fourth resonator 134 is also relatively small, so that the cross-sectional area of ​​the second connecting part 144 in the direction from the third resonator 133 to the fourth resonator 134 is larger, which can increase the coupling amount between the third resonator 133 and the fourth resonator 134.

[0102] Alternatively, in yet another possible implementation, see [link to previous section]. Figure 5 and Figure 6 As shown, a third coupling groove 147 can also be formed on the top surface 113 of the medium entity 110. The first coupling through hole 140, the second coupling through hole 141, and the third coupling through hole 143 can all be formed on the bottom wall of the third coupling groove 147. In this case, it can also be understood that the first coupling groove 145 and the second coupling groove 146 are connected. For example, the third coupling groove 147 can pass through from one end of the medium entity 110 to the other end, and then the first coupling through hole 140, the second coupling through hole 141, and the third coupling through hole 143 are respectively formed on the bottom wall of the third coupling groove 147.

[0103] See also Figure 5 and Figure 6 As shown, in some examples, a fifth coupling via 151 may also be provided on the top surface 113 of the dielectric entity. The fifth coupling via 151 may be located between two adjacent sets of resonant blind vias. For example, in the embodiments of this application, the fifth coupling via 151 may be provided between the adjacent first set of resonant blind vias 120 and the second set of resonant blind vias 130. The fifth coupling via 151 can further adjust the size of the coupling channel between the first resonator 123 and the third resonator 133, and between the second resonator 124 and the fourth resonator 134, so that different coupling amounts can be achieved between two adjacent resonators.

[0104] For example, taking the coupling between the first resonator 123 and the third resonator 133 as an example, the fifth coupling via 151 can be as follows: Figure 5The elongated through-hole shown in the figure has a relatively large cross-sectional area in the direction from the first resonator 123 to the third resonator 133. This can make the coupling channel between the first resonator 123 and the third resonator 133 relatively small, which can further reduce the coupling amount between the first resonator 123 and the third resonator 133.

[0105] Alternatively, the fifth coupling through hole 151 can also be a cylindrical through hole. In this case, the cross-sectional area of ​​the fifth coupling through hole 151 in the direction from the first resonator 123 to the third resonator 133 is relatively small, which can make the coupling channel between the first resonator 123 and the third resonator 133 relatively large, and can achieve a relatively large coupling amount between the first resonator 123 and the third resonator 133.

[0106] In this embodiment, the number of the first group of resonant blind vias 120 and the second group of resonant blind vias 130 can be multiple, and the multiple first group of resonant blind vias 120 and the multiple second group of resonant blind vias 130 can be arranged alternately. For example, see... Figure 6 As shown, the number of the first group of resonant blind holes 120 can be two, and the number of the second group of resonant blind holes 130 can be three. There can be one first group of resonant blind hole 120 between every two second group of resonant blind holes 130.

[0107] The arrangement of the first set of resonant blind apertures 120 and the second set of resonant blind apertures 130 can affect the filtering result of the dielectric filter 100. For example, when the first set of resonant blind apertures 120 and the second set of resonant blind apertures 130 are arranged in an alternating manner, the dielectric filter 100 can obtain signals in a certain frequency band while filtering out signals outside that frequency band. However, when the first set of resonant blind apertures 120 and the second set of resonant blind apertures 130 are arranged in other ways, for example, the dielectric filter 100 can obtain signals in another frequency band while filtering out signals outside that frequency band.

[0108] For example, in some examples, multiple first-group resonant blind vias 120 may be arranged adjacent to each other, followed by multiple second-group resonant blind vias 130 arranged sequentially. Specifically, the arrangement of the first-group resonant blind vias 120 and the second-group resonant blind vias 130 can be selected and set according to the filtering requirements of the dielectric filter 100. In this embodiment, the alternating arrangement of the first-group resonant blind vias 120 and the second-group resonant blind vias 130 will be used as an example for explanation.

[0109] Figure 7 This is a schematic diagram of another dielectric filter structure provided in an embodiment of this application. Figure 8 This is a top view of another dielectric filter provided in an embodiment of this application.

[0110] Or, in some examples, see Figure 7 and Figure 8 As shown, a fourth coupling groove 148 can also be formed on the top surface 113 of the dielectric entity 110, and the first coupling through hole 140 and the third coupling through hole 143 can be formed on the bottom wall of the fourth coupling groove 148. For example, the first set of resonators (i.e., the resonators formed by the first set of resonant blind holes 120) and the second set of resonators (i.e., the resonators formed by the second set of resonant blind holes 130) can be arranged adjacent to each other. In this case, the fourth coupling groove 148 can be formed on the top surface 113 of the dielectric entity 110. The fourth coupling groove 148 can extend from the first set of resonators to the position where the first coupling through hole 140 is formed in the second set of resonators, and then the first coupling through hole 140 and the third coupling through hole 143 are formed on the bottom wall of the fourth coupling groove 148.

[0111] See also Figure 7 and Figure 8 As shown, a fourth coupling through hole 149 may also be provided on the dielectric entity 110. The fourth coupling through hole 149 may be located on the first side 111 or the second side 112 of the dielectric entity 110, and the fourth coupling through hole 149 may be located between two adjacent sets of resonant blind holes.

[0112] For example, in this embodiment, the fourth coupling via 149 can be formed between adjacent first group of resonant blind vias 120 and second group of resonant blind vias 130. Resonators formed by two adjacent resonant blind vias on the same side can also be coupled; for example, the first resonator 123 formed by the first resonant blind via 121 and the third resonator 133 formed by the third resonant blind via 131 can also be coupled. Correspondingly, the second resonator 124 and the fourth resonator 134 can also be coupled. The fourth coupling via 149 can adjust the size of the coupling channel between the first resonator 123 and the third resonator 133, or between the second resonator 124 and the fourth resonator 134.

[0113] For example, when the fourth coupling via 149 is located on the first side 111 of the dielectric entity 110, the fourth coupling via 149 can adjust the size of the coupling channel between the first resonator 123 and the third resonator 133. When the fourth coupling via 149 is located on the second side 112 of the dielectric entity 110, the fourth coupling via 149 can adjust the size of the coupling channel between the second resonator 124 and the fourth resonator 134.

[0114] For example, taking the coupling between the first resonator 123 and the third resonator 133 as an example, the fourth coupling through-hole 149 can be a cylindrical through-hole with a small cross-sectional area in the direction from the first resonator 123 to the third resonator 133. In this case, the coupling channel between the first resonator 123 and the third resonator 133 is relatively large, allowing for a larger coupling amount between them. Alternatively, the fourth coupling through-hole 149 can also be an elongated through-hole with a larger cross-sectional area in the direction from the first resonator 123 to the third resonator 133. In this case, the coupling channel between the first resonator 123 and the third resonator 133 is relatively small, allowing for a smaller coupling amount between them.

[0115] In specific applications, the cross-sectional shape and size of the fourth coupling via 149 can be designed according to the coupling requirements between the first resonator 123 and the third resonator 133.

[0116] Correspondingly, the fourth coupling via 149 also has the same effect on controlling the coupling amount between the second resonator 124 and the fourth resonator 134, which will not be elaborated here.

[0117] The fourth coupling through hole 149 located on the first side 111 and the fourth coupling through hole 149 located on the second side 112 can be coaxially arranged, or they can be staggered. Specifically, the positions of the fourth coupling through hole 149 on the first side 111 and the fourth coupling through hole 149 on the second side 112 can be selected and set according to specific application requirements.

[0118] Alternatively, in some examples, a fifth coupling groove 150 may be provided on the top surface 113 of the medium entity 110 (see...). Figure 3 and Figure 4 As shown, the fifth coupling groove 150 can extend from the first side 111 of the dielectric entity 110 to the second side 112, and the fifth coupling groove 150 can be located between two adjacent sets of resonant blind holes. For example, in the embodiments of this application, the fifth coupling groove 150 can be formed between adjacent first set of resonant blind holes 120 and second set of resonant blind holes 130. The fifth coupling groove 150 can also adjust the size of the coupling channel between the first resonator 123 and the third resonator 133, and between the second resonator 124 and the fourth resonator 134, so that different coupling amounts can be achieved between adjacent resonators.

[0119] Taking the coupling between the first resonator 123 and the third resonator 133 as an example, the greater the depth of the fifth coupling groove 150, the larger its cross-sectional area in the direction from the first resonator 123 to the third resonator 133, and the smaller the coupling channel between the first resonator 123 and the third resonator 133, resulting in a smaller coupling amount between them. Conversely, the smaller the depth of the fifth coupling groove 150, the smaller its cross-sectional area in the direction from the first resonator 123 to the third resonator 133, and the larger the coupling channel between them, resulting in a smaller coupling amount between them. In specific applications, the depth of the fifth coupling groove 150 can be designed according to the coupling requirements between the first resonator 123 and the third resonator 133.

[0120] In this embodiment, the first resonant blind aperture 121 and the second resonant blind aperture 122 in the first group of resonant blind apertures 120 can be coaxially arranged, and the third resonant blind aperture 131 and the fourth resonant blind aperture 132 in the second group of resonant blind apertures 130 can also be coaxially arranged. This improves the regularity of the overall structure of the dielectric filter 100 and facilitates its design and production. Furthermore, when performing simulation calculations on the dielectric filter 100, the dimensions of each resonant blind aperture can be easily determined, improving operational efficiency.

[0121] Figure 9 This is a schematic diagram of a signal input terminal configuration provided in an embodiment of this application.

[0122] In the embodiments of this application, see Figure 9 As shown, the dielectric filter 100 may further include a signal input terminal 160, which can be connected to the first resonator 123. Electromagnetic wave signals can be input from the signal input terminal 160 and enter the dielectric filter 100 through the first resonator 123.

[0123] For example, see Figure 9 As shown, a first coupling blind hole 161 can also be provided on the dielectric entity 110. One end of the first coupling blind hole 161 can be connected to the signal input terminal 160, and the other end of the first coupling blind hole 161 can be connected to the first resonant blind hole 121. The signal input terminal 160 can be coupled and fed to the first resonator 123 through the first coupling blind hole 161 so that the electromagnetic wave signal can be fed into the dielectric filter 100.

[0124] Of course, in some examples, the signal input terminal 160 can also be connected to the second resonator 124, the third resonator 133 or the fourth resonator 134 to realize the input of electromagnetic wave signals.

[0125] See also Figure 9 As shown, a sixth coupling groove 162 can also be formed on the dielectric entity 110. One end of the sixth coupling groove 162 can be connected to the other end of the first coupling blind hole 161, and the other end of the sixth coupling groove 162 can be connected to the first resonant blind hole 121. The signal input terminal 160 can be fed and coupled to the first resonator 123 through the first coupling blind hole 161 and the sixth coupling groove 162 in sequence to realize the signal input.

[0126] Correspondingly, the dielectric filter 100 may also include a signal output terminal (not shown in the figure). The signal output terminal can be connected to the second resonator 124. After the electromagnetic wave signal is fed into the dielectric filter 100 from the signal input terminal 160, it can be repeatedly reflected in the dielectric entity 110 and finally output from the signal output terminal to complete the filtering function of the dielectric filter 100.

[0127] The signal connection between the signal output terminal and the second resonator can be set with reference to the connection between the signal input terminal 160 and the first resonator 123, and will not be described in detail here.

[0128] Alternatively, in some examples, the signal output terminal can also be connected to the second resonator 124, the third resonator 133, or the fourth resonator 134 to achieve the output of electromagnetic wave signals.

[0129] This application also provides a communication device, which may include the dielectric filter 100 in any of the above examples. For example, the communication device may be a communication base station, satellite communication, navigation system, etc. The dielectric filter 100 can filter out interference signals in the communication device to improve the signal stability and reliability of the communication device operation.

[0130] By including the aforementioned dielectric filter 100 in the communication device, the installation space occupied by the dielectric filter 100 in the communication device can be effectively reduced, which is beneficial to improving the rationality and regularity of the internal device layout.

[0131] For example, the communication device may also include an antenna, which can be signal-connected to the dielectric filter 100. The antenna can be used to transmit and receive signals, and the dielectric filter 100 is used to filter the signals received by the antenna or to transmit filtered signals to the antenna.

[0132] The following simulation test is conducted on the dielectric filter 100 provided in the embodiments of this application, with reference to the accompanying drawings.

[0133] Figure 10 This is a signal return efficiency diagram of a dielectric filter in related technologies. Figure 11This is a signal return efficiency diagram of a dielectric filter provided in an embodiment of this application.

[0134] See Figure 10 As shown in the figure, the horizontal axis represents frequency, and the vertical axis represents signal power. The further the vertical axis value of the curve is from 0, the less signal flows from the input to the output, meaning that the signal at that frequency is filtered out by the dielectric filter 100 and is not output from the signal output terminal. Conversely, the closer the vertical axis value of the curve is to 0, the more signal flows from the input to the output, indicating that the signal at that frequency passes through the dielectric filter 100 and is output from the output terminal of the dielectric filter 100.

[0135] Therefore, from Figure 10 It can be concluded that the dielectric filter 100 in the related technology has a resonant point in the 3.5 GHz frequency band, and signals in this frequency band pass through the dielectric filter 100. Furthermore, from... Figure 10 It can also be concluded that two low-frequency resonant points appeared near the frequency of 2.5GHz. There were fewer signal echoes at this point, and some energy passed through the dielectric filter 100, indicating that the dielectric filter 100 had a poor signal suppression effect at this frequency.

[0136] Furthermore, in the 6.0GHz–6.5GHz frequency band, the dielectric filter 100 exhibits higher-order mode resonance, i.e., an out-of-band resonance mode. An out-of-band resonance mode refers to the dielectric filter 100 resonating outside the passband. Higher-order mode resonance refers to out-of-band resonance modes with resonant frequencies near two or several harmonics of the passband, which generates parasitic passbands near these harmonics, causing a deterioration in the suppression effect of the filter near these harmonics. Therefore, it can be concluded from the figure that the dielectric filter 100 in the related technology has a poor suppression effect on higher-order mode signals.

[0137] Typically, in related technologies, to address the issue of high-order mode resonance, stub lines of low-pass traces are added to the dielectric filter 100 to suppress high-order mode signals during its use. However, this method suffers from significant insertion loss, increasing the overall loss of the dielectric filter. Furthermore, it occupies a larger area on the circuit board and increases the cost of the dielectric filter.

[0138] See Figure 11 As shown, Figure 11 The signal return efficiency diagram of the dielectric filter 100 provided in the embodiments of this application is from... Figure 11 As can be seen, there is a resonant point in the 3.5GHz frequency band, and signals in this band pass through the dielectric filter 100. However, no resonant signal was observed. Figure 10This eliminates the low-frequency resonance and high-order mode resonance that may occur in the dielectric filter 100. Therefore, the dielectric filter 100 does not require additional low-pass routing stubs during use, avoiding insertion loss issues caused by adding low-pass routing and effectively reducing the loss and cost of the dielectric filter 100.

[0139] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, an indirect connection through an intermediate medium, or the internal connection of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application according to the specific circumstances. The terms "first," "second," "third," "fourth," etc. (if present) are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0140] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the embodiments of this application, and are not intended to limit them. Although the embodiments of this application have been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A dielectric filter characterized by, Includes a medium entity having opposing first and second sides and a top surface located between the first and second sides; At least one set of resonant blind holes are formed on the dielectric entity, and the at least one set of resonant blind holes includes a first set of resonant blind holes, which includes a first resonant blind hole and a second resonant blind hole. The first resonant blind aperture is located on the first side, and the second resonant blind aperture is located on the second side; The first resonant blind hole and the dielectric material surrounding it form a first resonator, and the second resonant blind hole and the dielectric material surrounding it form a second resonator. The top surface of the dielectric entity is provided with a first coupling through hole and a second coupling through hole, and a first connection portion is provided between the first coupling through hole and the second coupling through hole. The first resonator and the second resonator are negatively coupled through the first connection portion.

2. The dielectric filter according to claim 1, characterized in that, The at least one set of resonant blind holes also includes a second set of resonant blind holes, the second set of resonant blind holes including a third resonant blind hole and a fourth resonant blind hole; The third resonant blind hole is located on the first side, and the fourth resonant blind hole is located on the second side; The third resonant blind hole and the dielectric material around it form a third resonator, and the fourth resonant blind hole and the dielectric material around it form a fourth resonator. A third coupling through hole is provided on the top surface of the dielectric entity, and two second connecting parts are provided on both sides of the third coupling through hole. The third resonator and the fourth resonator are positively coupled through the two second connecting parts.

3. The dielectric filter according to claim 2, characterized in that, The top surface of the medium entity is further provided with a first coupling groove, and the first coupling through hole and the second coupling through hole are both provided on the bottom wall of the first coupling groove.

4. The dielectric filter according to claim 2 or 3, characterized in that, A second coupling groove is also provided on the top surface of the medium entity, and a third coupling through hole is provided on the bottom wall of the second coupling groove.

5. The dielectric filter according to claim 2 or 3, characterized in that, A third coupling groove is also provided on the top surface of the medium entity, and the first coupling through hole, the second coupling through hole and the third coupling through hole are all provided on the bottom wall of the third coupling groove.

6. The dielectric filter according to claim 2 or 3, characterized in that, A fourth coupling groove is also provided on the top surface of the medium entity, and the first coupling through hole and the third coupling through hole are both provided on the bottom wall of the fourth coupling groove.

7. The dielectric filter according to claim 2 or 3, characterized in that, The medium entity is also provided with a fourth coupling through hole; The fourth coupling via is located on the first side or the second side of the dielectric entity, and the fourth coupling via is located between two adjacent sets of resonant blind vias.

8. The dielectric filter according to claim 2 or 3, characterized in that, A fifth coupling groove is also provided on the top surface of the medium entity; The fifth coupling groove extends from the first side of the dielectric entity to the second side, and the fifth coupling groove is located between the adjacent first group of resonant blind holes and the second group of resonant blind holes.

9. The dielectric filter according to claim 2 or 3, characterized in that, A fifth coupling through hole is also provided on the top surface of the medium entity; The fifth coupling via is located between the adjacent first group of resonant blind vias and the second group of resonant blind vias.

10. The dielectric filter according to claim 2 or 3, characterized in that, The number of the first group of resonant blind holes and the second group of resonant blind holes is multiple; Multiple first-group resonant blind holes and multiple second-group resonant blind holes are arranged alternately.

11. The dielectric filter according to claim 2 or 3, characterized in that, The first resonant blind hole and the second resonant blind hole in the first group of resonant blind holes are coaxially arranged; The third and fourth resonant blind holes in the second group of resonant blind holes are coaxially arranged.

12. The dielectric filter according to any one of claims 1 to 3, characterized in that, The dielectric filter further includes a conductive layer that covers the surface of the dielectric entity.

13. The dielectric filter according to any one of claims 1 to 3, characterized in that, The dielectric filter also includes a signal input terminal; The signal input terminal is connected to the signal of the first resonator.

14. The dielectric filter according to claim 13, characterized in that, The medium entity is also provided with a first coupling blind hole; One end of the first coupling blind hole is connected to the signal input terminal, and the other end of the first coupling blind hole is connected to the first resonant blind hole.

15. The dielectric filter according to claim 14, characterized in that, The medium entity is also provided with a sixth coupling groove; One end of the sixth coupling groove is connected to the other end of the first coupling blind hole, and the other end of the sixth coupling groove is connected to the first resonant blind hole.

16. The dielectric filter according to any one of claims 1 to 3, characterized in that, The dielectric filter also includes a signal output terminal; The signal output terminal is connected to the signal of the second resonator.

17. A communication device, characterized in that, Includes the dielectric filter as described in any one of claims 1 to 16.

18. The communication device according to claim 17, characterized in that, The communication device further includes an antenna, which is signal-connected to the dielectric filter.

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