WO2021035805A1

WO2021035805A1 - Filter and filter loop structure thereof

Info

Publication number: WO2021035805A1
Application number: PCT/CN2019/105226
Authority: WO
Inventors: 谢懿非; 丁海; 林显添
Original assignee: 京信通信技术(广州)有限公司
Priority date: 2019-08-27
Filing date: 2019-09-10
Publication date: 2021-03-04
Also published as: CN110429364B; CN110429364A

Abstract

The present invention relates to a filter and a filter loop structure thereof. By means of providing a coupling branch, two coupling loops can be formed in a main loop. Moreover, since each coupling loop includes a capacitive coupling structure, a phase difference is generated in each coupling loop, such that a pair of zero points can be generated in each coupling loop. Therefore, compared with traditional filters, the filter has a pair of new zero points, and is of a six-cavity four-zero-point structure. Moreover, there is no need to change an arranged cavity structure of a filter loop, and a coupling branch only needs to be added, and the capacitive coupling structure only needs to be provided at a suitable position. In addition, a first resonator and a tail resonator in a main loop are provided on the same side, thereby facilitating the arrangement of input and output ports and being beneficial to saving on layout space of the filter. Therefore, the filter and the filter loop structure thereof have a simpler structure while achieving multiple zero points.

Description

Filter and its filtering loop structure

Technical field

The present invention relates to the field of communication technology, in particular to a filter and its filter loop structure.

Background technique

As a frequency selection device, the filter is a very critical component in communication equipment. With the rapid development of communication technology, whether the device can achieve low insertion loss has become the key to restricting its development. The usual practice is to increase the number of zeros to widen the passband and improve the suppression, so as to achieve the purpose of reducing the insertion loss. When increasing the zero point of the traditional filter, the cavity structure of the filter generally needs to be redesigned. Therefore, although multiple zeros can be realized, the structure is complicated.

Summary of the invention

Based on this, it is necessary to provide a filter with simple structure and capable of realizing multiple zeros and its filter loop structure.

A filter loop structure, including six resonators, the six resonators are arranged in sequence along a signal transmission path to form a main loop, a coupling adjustment structure is arranged between the first resonator and the tail resonator, and the main loop is not phased Two adjacent resonators are connected to form a coupling branch, and cooperate with the main loop to form two coupling loops, and each of the coupling loops includes a capacitive coupling structure;

Wherein, six of the resonators are distributed on a first side and a second side opposite to the first side, and the first resonator and the tail resonator are located on the same side.

In one of the embodiments, the six resonators are respectively a first resonator, a second resonator, a third resonator, a fourth resonator, a fifth resonator, and a sixth resonator arranged in sequence. The first resonator and the sixth resonator respectively constitute the first resonator and the tail resonator, and three of the resonators are distributed on the first side and the second side respectively.

In one of the embodiments, the resonator located in the middle position of the first side is connected to the resonator located in the middle position of the second side to form the coupling branch.

In one of the embodiments, the second resonator, the third resonator, and the fourth resonator are sequentially distributed on the first side, and the first resonator, the sixth resonator, and the The fifth resonator is sequentially distributed on the second side, and the third resonator and the sixth resonator are connected to form the coupling branch.

In one of the embodiments, it includes two stacked dielectric blocks, the second resonator, the third resonator, and the fourth resonator are formed in one of the dielectric blocks, and the first resonator The device, the six resonator, and the fifth resonator are formed in another dielectric block.

In one of the embodiments, the capacitive coupling structure is arranged between the two resonators to form the coupling branch, and the two coupling loops share the capacitive coupling structure.

In one of the embodiments, an inductive coupling structure is provided between the two resonators to form the coupling branch, and the capacitive coupling structure in each coupling loop is arranged in addition to the coupling branch. Between two adjacent resonators.

In one of the embodiments, the coupling adjustment structure is a cross-coupling mechanism, which can switch between capacitive coupling and inductive coupling between the first resonator and the tail resonator.

In one of the embodiments, the coupling adjustment structure includes an adjustment slot provided between the first resonator and the tail resonator, and an end of the adjustment slot and the sidewall of the resonator Adjustable spacing.

A filter includes the filter loop structure as described in any one of the above preferred embodiments.

The above-mentioned filter and its filtering loop structure can form two coupling loops in the main loop by setting the coupling branch. Moreover, since each coupling loop includes a capacitive coupling structure, a phase difference is generated in each coupling loop, so that a pair of zeros can be generated in each coupling loop. Therefore, compared with the traditional filter, the above-mentioned filter adds a pair of zero points, which is a 6-cavity 4-zero point structure. Moreover, the cavity structure of the filter loop does not need to be changed, only the coupling branch is added and the capacitive coupling structure is set at a suitable position. In addition, since the first resonator and the tail resonator in the main loop are arranged on the same side, it is convenient to lay out the input and output ports, and it is helpful to save the layout space of the filter. Therefore, the above-mentioned filter and its filter loop structure have a simpler structure while realizing multiple zeros.

Description of the drawings

Fig. 1 is a schematic structural diagram of a filter loop structure in an embodiment of the present invention;

Figure 2 is an equivalent circuit diagram of the filter loop structure shown in Figure 1;

Figure 3 is an equivalent circuit diagram of a filter loop structure in other embodiments of the present invention;

Figure 4 is an equivalent circuit diagram of a filter loop structure in other embodiments of the present invention;

Figure 5 is an equivalent circuit diagram of a filter loop structure in other embodiments of the present invention;

Fig. 6 is an equivalent circuit diagram of a filter loop structure in other embodiments of the present invention;

Fig. 7 is an equivalent circuit diagram of a filter loop structure in other embodiments of the present invention;

Fig. 8 is an equivalent circuit diagram of a filter loop structure in other embodiments of the present invention;

Fig. 9 is a schematic structural diagram of a filter loop structure in another embodiment of the present invention.

detailed description

In order to facilitate the understanding of the present invention, the present invention will be more fully described below with reference to the relevant drawings. The drawings show preferred embodiments of the present invention. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or a central element may also be present. When an element is considered to be "connected" to another element, it can be directly connected to the other element or an intermediate element may be present at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field of the present invention. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The term "and/or" as used herein includes any and all combinations of one or more related listed items.

Please refer to FIG. 1, the present invention provides a filter and filter loop structure 100. Among them, the filter includes a filter loop structure 100. Moreover, the above-mentioned filter may be a dielectric filter or a metal cavity filter.

Please also refer to FIGS. 2 to 8, the filter loop structure 100 in an embodiment of the present invention includes six resonators 110, a coupling adjustment structure 120 and a capacitive coupling structure 130.

The six resonators 110 are arranged in sequence along the signal transmission path to form a main loop, and a coupling adjustment structure 120 is arranged between the first resonator and the last resonator. Through the adjustment of the coupling adjustment structure 120, the coupling between the head resonator and the tail resonator can be realized, and the signal can be transmitted from the head resonator to the tail resonator in the main loop. The first resonator and the tail resonator can be capacitively coupled or inductively coupled. Moreover, the first resonator and the tail resonator are respectively used to connect to the input connector and the output connector of the above-mentioned filter.

The six resonators 110 are respectively a first resonator 110a, a second resonator 110b, a third resonator 110c, a fourth resonator 110d, a fifth resonator 110e, and a sixth resonator 110f arranged in sequence. The signal may be sequentially transmitted along the first resonator 110a, the second resonator 110b, the third resonator 110c, the fourth resonator 110d, the fifth resonator 110e, and the sixth resonator 110f. It needs to be pointed out that similar terms such as "first" and "second" in the text do not represent specific quantities and sequences, but are merely convenient for distinction.

Two non-adjacent resonators 100 in the main loop are connected to form a coupling branch 11 and cooperate with the main loop to form two coupling loops, and each coupling loop includes a capacitive coupling structure 130. The capacitive coupling structure 130 can be realized and adjusted by providing coupling slots and coupling holes, and can be any existing structure capable of adjusting the amount of capacitive coupling. Specifically, the two resonators 100 forming the coupling branch 11 may be capacitively connected or inductively connected.

Because of the formation of two coupling loops. Moreover, each coupling loop includes a capacitive coupling structure 130, so a phase difference is generated in each coupling loop, so that a pair of zeros can be generated in each coupling loop. In other words, the above filter loop result 100 has two pairs of zeros. Compared with the traditional filter, the above-mentioned filter adds a pair of zero points, which is a 6-cavity 4-zero point structure. Therefore, it can effectively reduce the insertion loss and improve the out-of-band suppression.

The row cavity structure of the six resonators 110 can be the same as the existing filter circuit. Among them, six resonators are distributed on the first side and the second side opposite to the first side, and the first resonator and the tail resonator are located on the same side. That is, the first resonator and the tail resonator are located on the first side or the second side at the same time. On the one hand, this setting is convenient for simulation; on the other hand, it can be connected to the signal input port (first resonator) and signal output port (tail resonator) of the main circuit at the same time by opening the corresponding connection port on a circuit board and other connecting components. ) To connect, so it is convenient to lay out the input and output ports, and is helpful to save the layout space of the filter.

Moreover, the cavity structure of the filter loop does not need to be changed, only the coupling branch is added and the capacitive coupling structure 130 is set at a suitable position. Therefore, the above-mentioned filter and its filter loop structure 100 have a simpler structure while realizing multiple zeros.

In one embodiment, three resonators 110 are respectively distributed on the first side and the second side. There are many ways to arrange the six resonators 110 on two sides, as long as the first resonator 110a and the sixth resonator 110f are on the same side. for example:

As shown in FIG. 2, the first side is distributed with the first resonator 110a, the sixth resonator 110f, and the fifth resonator 110e; the second side is distributed with the second resonator 110b, the third resonator 110c, and the fourth resonator 110d. As shown in FIG. 9, the second resonator 110b, the first resonator 110a, and the sixth resonator 110f may also be distributed on the first side; and the third resonator 110c, the fourth resonator 110d, and the fifth resonator may be distributed on the second side.器110e. Moreover, the position of the first side and the second side can also be reversed.

Since three resonators 110 are distributed on both sides, the symmetry of the filter loop structure 100 is better, which not only facilitates the layout of the filter, but also improves the filtering performance.

In one embodiment, the filter loop structure 100 includes two stacked dielectric blocks. The second resonator 110b, the third resonator 110c, and the fourth resonator 110d are formed in one of the dielectric blocks. The resonator 110f and the fifth resonator 110e are formed in another dielectric block.

When assembling, three resonators 110 can be formed on the dielectric block first, and then the two dielectric blocks can be superimposed according to the preset, so the assembly is more convenient.

In one embodiment, the resonator 110 located in the middle position of the first side is connected to the resonator 110 located in the middle position of the second side to form a coupling branch.

Since the two resonators 110 at the middle position of the first side and the second side are arranged oppositely, there is no need to set up flying leads when realizing the connection, and the coupling of the two resonators 110 can be realized directly by opening a window, setting a metal rod, etc., and The formation of coupling branches is conducive to simplifying the structure. Moreover, the two coupling loops formed each include four resonators 110, which have a high degree of symmetry, which is beneficial to further improve the filtering performance.

As shown in FIG. 2, in one embodiment, a first resonator 110a, a sixth resonator 110f, and a fifth resonator 110e are distributed on the first side, and a second resonator 110b, a third resonator 110b and the third resonator are distributed on the second side. 110c and the fourth resonator 110d. At this time, the third resonator 110c and the sixth resonator 110f are connected to form a coupling branch. The first coupling loop 12 includes a first resonator 110a, a second resonator 110b, a third resonator 110c, and a sixth resonator 110f; the second coupling loop 13 includes a third resonator 110c, a fourth resonator 110d, The fifth resonator 110e and the sixth resonator 110f.

As shown in FIG. 9, in another embodiment, the second resonator 110b, the first resonator 110a, and the sixth resonator 110f are distributed on the first side, and the third resonator 110c, the fourth resonator 110c and the fourth resonator are distributed on the second side. 110d and the fifth resonator 110e. At this time, the first resonator 110a and the fourth resonator 110d are connected to form a coupling branch. The first coupling loop 12 includes a first resonator 110a, a second resonator 110b, a third resonator 110c, and a fourth resonator 110d; the second coupling loop 13 includes a fourth resonator 110d, a fifth resonator 110e, The sixth resonator 110f and the first resonator 110a.

The capacitive coupling structure 130 can be shared between the two coupling loops, or the capacitive coupling structure 130 can be provided separately. As shown in FIGS. 1 and 2, in one embodiment, a capacitive coupling structure 130 is provided between two resonators 110 to form a coupling branch, and the two coupling loops share the capacitive coupling structure 130.

At this time, the two resonators 110 constituting the coupling branch are capacitively coupled, and the first resonator and the tail resonator are inductively coupled. Since the two coupling loops can share the capacitive coupling structure 130. Therefore, only one capacitive coupling structure 130 needs to be provided in the filter loop structure 100, which is beneficial to simplify the structure.

In addition, each coupling loop can also be individually provided with a capacitive coupling structure. As shown in FIGS. 3 to 8, in other embodiments, an inductive coupling structure is provided between the two resonators 110 to form a coupling branch, and the capacitive coupling structure 130 in each coupling loop is set in the decoupling branch. Between two adjacent resonators 110 outside the road.

In one embodiment, the coupling adjustment structure 120 is a cross-coupling mechanism, which can switch between capacitive coupling and inductive coupling between the head resonator and the tail resonator.

Specifically, when the cross-coupling structure is capacitive coupling, the cross-coupling structure can be used as the capacitive coupling structure 130 in the coupling loop. As shown in FIG. 7, the coupling adjustment structure 120 is used as the capacitive coupling structure 130. In this way, the coupling loop can be adjusted only by adjusting the capacitive coupling of the cross-coupling structure. Compared with using the coupling adjustment structure 120 to adjust the inductive coupling between the first and the last two resonators, the coupling loop is then used. In terms of other adjustment methods of the capacitive coupling structure 130, the adjustment of the coupling loop is simpler and more convenient.

Further, in one embodiment, the coupling adjustment structure 120 includes an adjustment slot 121 disposed between the first resonator and the tail resonator, and the distance between one end of the adjustment slot 121 and the sidewall of the resonator 110 is adjustable. Therefore, by flexibly adjusting the distance between one end of the adjusting slot 121 and the side wall of the resonator 110, that is, "L" shown in FIG. 1, the coupling amount between the two resonators at the head and the tail can be adjusted.

The above-mentioned filter and its filter loop structure 100 can form two coupling loops in the main loop by arranging coupling branches. Moreover, since each coupling loop includes the capacitive coupling structure 130, a phase difference is generated in each coupling loop, so that a pair of zeros can be generated in each coupling loop. Therefore, compared with the traditional filter, the above-mentioned filter adds a pair of zero points, which is a 6-cavity 4-zero point structure. Moreover, the cavity discharge structure of the filter loop 100 does not need to be changed, only the coupling branch is added and the capacitive coupling structure 130 is set at a suitable position. In addition, since the first resonator and the tail resonator in the main loop are arranged on the same side, it is convenient to lay out the input and output ports, and it is helpful to save the layout space of the filter. Therefore, the above-mentioned filter and its filter loop structure have a simpler structure while realizing multiple zeros.

The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, all possible combinations of the various technical features in the above-mentioned embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, All should be considered as the scope of this specification.

The above-mentioned embodiments only express several embodiments of the present invention, and the descriptions are more specific and detailed, but they should not be understood as limiting the scope of the invention patent. It should be pointed out that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can be made, and these all fall within the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention should be subject to the appended claims.

Claims

A filter circuit structure, characterized in that it comprises six resonators, the six resonators are arranged in sequence along the signal transmission path to form a main loop, a coupling adjustment structure is arranged between the first resonator and the tail resonator, and the main Two non-adjacent resonators in the loop are connected to form a coupling branch, and cooperate with the main loop to form two coupling loops, and each of the coupling loops includes a capacitive coupling structure;

Wherein, six of the resonators are distributed on a first side and a second side opposite to the first side, and the first resonator and the tail resonator are located on the same side.
The filter circuit structure according to claim 1, wherein the six resonators are respectively a first resonator, a second resonator, a third resonator, a fourth resonator, and a fifth resonator arranged in sequence. And a sixth resonator, the first resonator and the sixth resonator constitute the first resonator and the tail resonator, respectively, and the first side and the second side are respectively distributed with three Resonator.
The filter loop structure according to claim 2, wherein the resonator located in the middle position of the first side is connected to the resonator located in the middle position of the second side to form the coupling branch .
The filter circuit structure of claim 3, wherein the second resonator, the third resonator, and the fourth resonator are sequentially distributed on the first side, and the first resonator , The six resonators and the fifth resonator are sequentially distributed on the second side, and the third resonator and the sixth resonator are connected to form the coupling branch.
The filter loop structure according to claim 3, characterized in that it comprises two stacked dielectric blocks, the second resonator, the third resonator and the fourth resonator are formed in one of the A dielectric block, the first resonator, the sixth resonator, and the fifth resonator are formed in another dielectric block.
The filter loop structure according to any one of claims 1 to 5, wherein the capacitive coupling structure is arranged between the two resonators to form the coupling branch, and the two resonators The coupling loop shares the capacitive coupling structure.
The filter loop structure according to any one of claims 1 to 5, wherein an inductive coupling structure is arranged between the two resonators to form the coupling branch, and all of the coupling circuits are The capacitive coupling structure is arranged between two adjacent resonators except for the coupling branch.
The filter loop structure according to claim 1, wherein the coupling adjustment structure is a cross-coupling mechanism, which can switch between capacitive coupling and inductive coupling between the first resonator and the tail resonator .
The filter loop structure according to claim 8, wherein the coupling adjustment structure comprises an adjustment slot provided between the first resonator and the tail resonator, and one end of the adjustment slot is connected to the The spacing between the side walls of the resonator is adjustable.
A filter, characterized by comprising the filter loop structure according to any one of claims 1 to 9.