CN210778911U

CN210778911U - E-surface dielectric adjustable waveguide filter

Info

Publication number: CN210778911U
Application number: CN201921441211.3U
Authority: CN
Inventors: 陈勇; 唐波; 姚将锋; 王浩
Original assignee: Chengdu Spaceon Electronics Co Ltd
Current assignee: Chengdu Spaceon Electronics Co Ltd
Priority date: 2019-08-30
Filing date: 2019-08-30
Publication date: 2020-06-16
Anticipated expiration: 2029-08-30

Abstract

The utility model relates to a tunable waveguide filter of E face medium. The technical scheme is as follows: an E-plane dielectric tunable waveguide filter comprises a rectangular waveguide body; a coupling structure is arranged in the rectangular waveguide body, and the coupling structure divides the inner cavity of the rectangular waveguide body into a plurality of resonant cavities; at least one dielectric rod is inserted into one resonant cavity, a plurality of through holes are formed in the E surface of the rectangular waveguide body, one end of the dielectric rod extends out of the through holes, and one end, extending out of the through holes, of the dielectric rod is connected with a driving mechanism. The utility model provides a stable E face medium tunable waveguide filter of electrical property index in adjustable range.

Description

E-surface dielectric adjustable waveguide filter

Technical Field

The utility model belongs to the technical field of the wave filter, concretely relates to adjustable waveguide filter of E face medium.

Background

As communication systems evolve, more and more scenarios require filters that can accommodate different operating frequencies. For example, in some communication base station applications, in order to improve the spectrum utilization and save the cost, the operating frequency of the antenna system needs to be adjusted quickly according to the instruction. Obviously, the conventional fixed frequency filter does not have such capability, and to adjust the operating frequency of the antenna system, the filter in the antenna system must be replaced by a specified frequency filter, the system needs to be debugged again after the replacement, and the process is time-consuming. Under the background, the adjustable filter can be used for automatically adjusting the working frequency within a certain range, and after receiving an instruction, the adjustable filter can quickly and automatically adjust the working frequency to a specified frequency. Therefore, compared with a fixed frequency filter, a single adjustable filter can simultaneously support a plurality of frequency bands, has a rapid and automatic working frequency switching function, can effectively improve the frequency spectrum utilization rate, reduces the material cost and the operation cost, and has a wide application prospect.

Existing tunable filters are mainly implemented by adding a tuning component on the basis of a waveguide filter, and a mechanism for driving the tuning component. Patent WO2010150815a1 provides a tunable filter implemented by providing a rotatable dielectric sheet on an E-plane single-iris filter. However, the medium sheet can only rotate within the range of 0-90 degrees, tuning is very sensitive, and in order to meet the requirement of tuning stepping precision, the driving mechanism is complex in structure, large in size and high in cost. Patent WO2016095165a1 provides another tunable filter implemented based on an E-plane single-iris filter, in which a set of metal plates parallel to a metal coupling iris are provided, and a driving mechanism drives the metal plates to translate along the length direction of the waveguide so as to change the size of the resonant cavity for tuning. However, the scheme is not provided with a coupling compensation device, which may cause significant bandwidth variation in the tuning process and significant fluctuation of main indexes such as in-band echo, in-band insertion loss, out-of-band rejection and the like in the tuning process. In addition, the scheme of the E-plane single-diaphragm filter is adopted in both patent WO2010150815A1 and patent WO2016095165A1, the coupling adjustment parameters of the filter are few, and the bandwidth change in the tuning process is large. Patent CN107910624A provides a dielectric sheet-loaded tunable filter implemented based on an inductive window filter, tuning is achieved by inserting a PCB substrate into the cavity from the E-plane centerline. According to the scheme, the PCB substrate is used as a tuning medium, the dielectric sheet is thin and long, deformation is easy to generate, the anti-vibration performance is poor, and the electrical performance can be obviously deteriorated in the vibration process.

In conclusion, the existing tunable waveguide cavity filter has the problems of tuning sensitivity, obvious bandwidth change in the tuning process, obvious fluctuation of main indexes such as in-band echo, in-band insertion loss, out-of-band rejection and the like in the tuning process and the like; and in order to set a tuning medium, through holes are arranged on two sides of a cavity of the existing filter, so that electromagnetic leakage is excessive.

SUMMERY OF THE UTILITY MODEL

In order to solve the problems existing in the prior art, the utility model aims to provide an E-plane dielectric tunable waveguide filter with stable electrical performance indexes in a tunable range.

The utility model discloses the technical scheme who adopts does:

an E-plane dielectric tunable waveguide filter comprises a rectangular waveguide body; a coupling structure is arranged in the rectangular waveguide body, and the coupling structure divides the inner cavity of the rectangular waveguide body into a plurality of resonant cavities; at least one dielectric rod is inserted into one resonant cavity, a plurality of through holes are formed in the E surface of the rectangular waveguide body, one end of the dielectric rod extends out of the through holes, and one end, extending out of the through holes, of the dielectric rod is connected with a driving mechanism.

Preferably, at least two dielectric rods are inserted into the resonant cavity of the end part.

Preferably, the material of the dielectric rod may be one of plastic, quartz and ceramic.

Preferably, all the dielectric rods are irregularly arranged according to a shape like a Chinese character 'yi' or an 'S'.

Preferably, the coupling structure is a plurality of coupling partition walls, and the coupling partition walls are fixed in the rectangular waveguide body.

Preferably, the rectangular waveguide body includes a bottom groove, an E-face opening of the bottom groove, an E-face plate connected to the opening of the bottom groove, a through hole disposed on the E-face plate, and a coupling partition fixed in the bottom groove.

Preferably, the coupling structure comprises two metal coupling diaphragms, the two metal coupling diaphragms are sleeved in the rectangular waveguide body, and the metal coupling diaphragms are parallel to the H surface of the rectangular waveguide body; the metal coupling diaphragm is provided with a plurality of coupling strips, and the resonant cavity is formed by separating the coupling strips on the two metal coupling diaphragms.

Preferably, the rectangular waveguide body comprises two H-face grooves, an E-face plate is connected between two ends of each H-face groove, the through hole is formed in one of the E-face plates, and the two metal coupling diaphragms are sleeved in a space defined by the two H-face grooves and the two E-face plates.

Preferably, the drive mechanism is a linear motor.

One end of the adjustable element extends out of the through hole and is connected with the driving mechanism, and the driving mechanism is used for synchronously adjusting the insertion depth of the adjustable element into the resonant cavity to realize the adjustment of the frequency and the coupling strength of the adjustable filter

The utility model has the advantages that:

1. the utility model discloses in, waveguide filter's adjustable component is the dielectric rod, compares in medium thin slices such as PCB substrate, and the intensity of dielectric rod is higher, non-deformable, and consequently the reliability is higher, and the electrical property is also more stable.

2. The shapes of the dielectric rod include but are not limited to cylindrical and rectangular columnar forms, and the like, so that the adjustable element is ensured to have certain strength, is not easy to deform, has higher reliability, and can reduce electrical deterioration caused by vibration.

3. The utility model discloses in, through position, size and the shape of adjusting the dielectric rod, satisfying under the condition of electrical property index, can reduce the dielectric rod quantity in the resonant cavity to one, the structure is simpler, the debugging is convenient, manufacturing cost reduces.

4. The utility model discloses only set up the through-hole in one side of rectangular waveguide body so that the dielectric rod passes, compare in the tunable filter scheme that both sides set up the through-hole, reduced manufacturing cost, dielectric rod's removal is controlled more easily. And when the through hole is arranged only on one side, the gap of the rectangular waveguide body is reduced, the electromagnetic leakage condition is correspondingly reduced, and the insertion loss is reduced. The advantages of the invention are not limited to the description, but rather are described in greater detail in the detailed description for better understanding.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

It will be appreciated by those skilled in the art that the objects and advantages that can be achieved with the present invention are not limited to the details set forth above, and that these and other objects that can be achieved with the present invention will be more clearly understood from the following detailed description.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic structural diagram of the present invention when the coupling structure is a coupling partition wall;

FIG. 2 is a cross-sectional view of the present invention when the coupling structure is a coupling partition wall and a plurality of dielectric rods are arranged in a line shape;

FIG. 3 is a cross-sectional view of the present invention when the coupling structure is a coupling partition wall and a plurality of dielectric rods are arranged in an "S" shape;

FIG. 4 is a schematic structural diagram of the present invention when the coupling structure is two metal coupling diaphragms;

fig. 5 is a cross-sectional view of the present invention when the coupling structure is two metal coupling diaphragms.

In the figure: 1-a rectangular waveguide; 11-E face; 12-H surface; 13-bottom groove; 14-E panels; 15-H face groove; 2-a coupling structure; 21-a coupling partition wall; 22-a metal sheet; 221-a metal coupling diaphragm; 3-a resonant cavity; 4-a coupling window; 5-a dielectric rod; 6-driving mechanism.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary and intended to be used for explaining the present invention, and should not be construed as limiting the present invention.

In the description of the present invention, it is to be understood that the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically limited otherwise.

In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

Example 1:

as shown in fig. 1, the present invention includes a rectangular waveguide 1, the side of the rectangular waveguide 1 includes an E-plane 11 and an H-plane 12; a coupling structure 2 is arranged in the rectangular waveguide body 1, the coupling structure 2 divides the inner cavity of the rectangular waveguide body 1 into a plurality of resonant cavities 3, and a coupling window 4 is arranged between every two adjacent resonant cavities 3; at least one dielectric rod 5 is inserted into one resonant cavity 3, a plurality of through holes are formed in the E surface 11 of the rectangular waveguide body 1, one end of the dielectric rod 5 extends out of the through holes, and one end, extending out of the through holes, of the dielectric rod 5 is connected with a driving mechanism 6.

The utility model discloses in, waveguide filter's adjustable component is dielectric rod 5, compares in PCB substrate or foil, and dielectric rod 5's intensity is higher, non-deformable, and consequently the reliability is higher, and the electrical property is also more stable.

The utility model discloses in, through position, size, shape and the quantity of adjusting dielectric rod 5, can reduce 5 quantity of dielectric rod in every resonant cavity 3 to one, make the structure simplify, manufacturing cost reduces, can guarantee the synchronous change of each resonant cavity frequency in the tuning process simultaneously to and normalized coupling coefficient is unchangeable basically, thereby guaranteed the stability of electrical performance index such as bandwidth, return loss and outband suppression in the tuning range. Since the end-to-end resonant cavities 3 need to compensate input-output coupling and middle cavity coupling simultaneously, at least two adjustable elements are inserted into the end resonant cavities 3, so that the invention is ensured to have stable electrical performance in a tuning range.

The utility model discloses only set up the through-hole in one side of rectangular waveguide body 1 so that dielectric rod 5 passes, reduced manufacturing cost, dielectric rod 5's removal is controlled more easily. And, when only the through-hole is provided at one side, the gap of the rectangular waveguide 1 is reduced, and accordingly the electromagnetic leakage is reduced, thereby reducing the insertion loss. When the through hole is provided only on one side, the stability of the dielectric rod 5 is further improved, and the jitter of the dielectric rod 5 during tuning is reduced.

The dielectric rod 5 is made of a dielectric with a certain dielectric constant, and can be made of plastic, quartz, ceramic and other dielectric materials according to actual conditions such as tuning range, resonant cavity size and the like, so that the cost can be saved.

As shown in fig. 2 and 3, all the dielectric rods 5 are arranged in a special shape such as a straight line shape or an S shape. The dielectric rod 5 may be positioned close to or even at the coupling element to compensate for the coupling coefficient. Therefore, the plurality of dielectric rods can be arranged according to the special shapes such as the shape of a Chinese character ' yi ' or the shape of an S ', and the like.

The coupling structure 2 is a plurality of coupling partition walls 21, and the coupling partition walls 21 are fixed in the rectangular waveguide body 1. The coupling partition walls 21 are fixed in the rectangular waveguide body 1, so that the rectangular waveguide body 1 can be divided into a plurality of resonant cavities 3, and tuning is facilitated by adjusting the depth of the dielectric rods 5 inserted into the resonant cavities 3. The rectangular waveguide 1 comprises a bottom groove 13, an E surface of the bottom groove 13 is open, an E panel 14 is connected to the opening of the bottom groove 13, a through hole is formed in the E panel 14, and a coupling partition wall 21 is fixed in the bottom groove 13. The opening of the bottom groove 13 is connected with an E panel 14, so that the E panel 4 can be adjusted according to the situation when being installed. The dielectric rods 5 are inserted into the through holes of the E-shaped panel 14, so that the positions of the dielectric rods 5 can be integrally shifted along with the E-shaped panel 14, and the integral adjustment is convenient.

As shown in fig. 1, in the present embodiment, the coupling partition wall is integrally formed with the bottom slot, wherein the cavity form of the resonant cavity includes, but is not limited to, a rectangular cavity. In this embodiment, a waveguide is used as an input/output port, and a coupling partition wall is used as an input/output coupling device. In practice, the input/output port form can be selected according to actual needs, for example, SMA joints are adopted, and the corresponding input/output coupling device adopts a waveguide coaxial converter.

As shown in fig. 1, 2 and 3, at least one dielectric rod 5 is disposed in each resonant cavity 3, and the number of the dielectric rods 5 disposed in each resonant cavity 3 may be the same or different. A dielectric rod 5 may also be provided at the coupling structure 2 to compensate for coupling, ensuring that the normalized coupling coefficient is unchanged during tuning. The E-face 11 of the respective rectangular waveguide 1 is provided with at least one through hole having a cross-sectional area slightly larger than that of the dielectric rod 5 so that the dielectric rod 5 can enter and exit the rectangular waveguide 1 without friction. The dielectric rod 5 is made of a dielectric with a certain dielectric constant, including but not limited to one of plastic, PCB substrate, quartz, teflon and ceramic. The loss tangent of the material of the dielectric rod 5 should be as small as possible to reduce the loss caused by the dielectric. The shape of the dielectric rod 5 of the present invention is cylindrical, but the present invention is not limited to the shape of the dielectric rod 5, including but not limited to cylindrical, rectangular cylindrical and elliptical cylindrical.

The dielectric rod 5 extends into the resonant cavity 3, so that the electromagnetic energy distribution in the resonant cavity 3 can be changed, and the resonant frequency of the resonant cavity 3 is reduced. The amount of frequency change is proportional to the volume and dielectric constant of the dielectric rod 5 inserted inside the resonant cavity 3. When the dielectric rod 5 is located away from the center of the cavity 3, the effect on the electromagnetic energy will be less, and thus the amount of frequency change for the same insertion volume will be less. The dielectric rod 5 can adjust not only the frequency of the resonant cavity 3, but also the coupling between the cavity and the input-output coupling. When the dielectric rod 5 is close to the coupling structure 2, the electromagnetic energy distribution at the coupling structure 2 is enhanced, and simultaneously, because the tuning element mechanism 2 is deviated from the center of the resonant cavity 3, the frequency of the resonant cavity 3 is also higher, and finally, the coupling is enhanced. By utilizing the rule, the number of the dielectric rods 5 arranged in the resonant cavity 3 can be reduced by skillfully arranging the positions of the dielectric rods 5. In general, as shown in fig. 2 and 3, the resonator 3 in the middle can be provided with at least one medium 5 for adjusting the frequency of the resonator 3 and compensating the coupling of the resonator 3 in the middle. However, since the front and rear resonators 3 need to compensate for the input-output coupling and the middle resonator 3 coupling at the same time, at least two dielectric rods 5 need to be provided. The dielectric rod 5 may be positioned close to or even at the coupling structure 2 to compensate for the coupling coefficient. The position of the dielectric rod 5 in the resonant cavity can be set according to the requirement, and the dielectric rod can be distributed on the central line of the E surface 11 of the rectangular waveguide body 1 in a straight shape or in a special shape according to the actual requirement.

One end of each dielectric rod 5 is fixed on the driving mechanism 6, so that the driving mechanism 6 can drive the dielectric rods to move in the rectangular waveguide body 1, and tuning is realized. The more the dielectric rod 5 extends into the rectangular waveguide body 1, the lower the filter frequency. The driving mechanism 6 is a linear motor. The driving mechanism 6 is a linear motor, so that the depth of the dielectric rod 5 extending into the resonant cavity 3 can be accurately adjusted.

Example 2:

as shown in fig. 4 and 5, the present invention includes a rectangular waveguide 1, the side of the rectangular waveguide 1 includes an E-plane 11 and an H-plane 12; a coupling structure 2 is arranged in the rectangular waveguide body 1, the coupling structure 2 divides the inner cavity of the rectangular waveguide body 1 into a plurality of resonant cavities 3, and a coupling window 4 is arranged between every two adjacent resonant cavities 3; at least one dielectric rod 5 is inserted into one resonant cavity 3, a plurality of through holes are formed in the E surface 11 of the rectangular waveguide body 1, one end of the dielectric rod 5 extends out of the through holes, and one end, extending out of the through holes, of the dielectric rod 5 is connected with a driving mechanism 6.

The utility model discloses in, waveguide filter's adjustable component is dielectric rod 5, compares in PCB substrate or sheetmetal, and dielectric rod 5's intensity is higher, non-deformable, and consequently the reliability is higher, and the electrical property is also more stable.

The dielectric rod 5 is made of one of plastic, PCB (printed circuit board) base materials, quartz, polytetrafluoroethylene and ceramics. The dielectric rod 5 is made of one of plastic, PCB (printed circuit board) base material, quartz, polytetrafluoroethylene and ceramic. In the waveguide filter, the dielectric rod 5 is only required to be a dielectric with a certain dielectric constant, and the material can be one of plastic, PCB (printed circuit board) base materials, quartz, polytetrafluoroethylene and ceramics, so that the cost can be correspondingly saved.

The coupling structure 2 comprises two metal sheets 22, the two metal sheets 22 are sleeved in the rectangular waveguide 1, and the metal sheets 22 are parallel to the H surface of the rectangular waveguide 1; the metal sheet 22 is composed of a plurality of metal coupling diaphragms 221 and metal connecting parts which are parallel up and down, wherein the metal connecting parts are parts of the waveguide wall, and the resonant cavity 3 is formed by separating the metal coupling diaphragms 221 on the two metal sheets 22. When the coupling structure 2 includes two parallel metal sheets 22, the number of metal coupling membranes 221 increases. The more metal sheets 22, the more adjustable parameters, and the easier the electrical performance index is.

The rectangular waveguide body 1 comprises two H-shaped grooves 15, E panels 14 are connected between two ends of the two H-shaped grooves 15, a through hole is formed in one of the E panels 14, and two metal sheets 22 are sleeved in a space defined by the two H-shaped grooves 15 and the two E panels 14. When the coupling structure 2 comprises the two metal sheets 22, the rectangular waveguide 1 comprises the two H-shaped grooves 15, and the two metal sheets 22 are sleeved in a space surrounded by the two H-shaped grooves 15 and the two E-shaped panels 14, so that the metal sheets 22 can be conveniently installed.

The resonant cavity 3 is formed by separating the metal coupling membranes 221 on the two metal sheets 22, the metal coupling membrane 221 at the middle part of the metal sheet 22 is used for controlling the coupling of the resonant cavity 3 in the middle, and the resonant cavities 3 at the head and the tail and the end parts of the metal sheets 22 are used for controlling the input and output coupling. In this embodiment, although the implementation is based on an E-plane double-diaphragm filter, the number of the E-plane metal sheets 22 may be determined as needed. The more metal sheets 22, the more adjustable parameters, the easier the electrical performance index is to achieve, but the more complicated the design is. In this embodiment, the rectangular waveguide 1 is used to implement input and output, and the E-plane metal sheet 22 is used to implement input and output coupling, but in practice, other input and output ports may also be used, for example, SMA joints are used, and the corresponding input and output coupling structure may be a waveguide coaxial converter. In this embodiment, the cylindrical dielectric rod 5 is used to adjust the frequency and the coupling, but the present invention does not limit the shape thereof.

The present invention is not limited to the above-mentioned optional embodiments, and any other products in various forms can be obtained by anyone under the teaching of the present invention, and any changes in the shape or structure thereof, all the technical solutions falling within the scope of the present invention, are within the protection scope of the present invention.

Claims

1. An E-plane dielectric tunable waveguide filter includes a rectangular waveguide body (1); a coupling structure (2) is arranged in the rectangular waveguide body (1), and the coupling structure (2) divides the inner cavity of the rectangular waveguide body (1) into a plurality of resonant cavities (3); the method is characterized in that: at least one dielectric rod (5) is inserted into one resonant cavity (3), a plurality of through holes are formed in the E surface (11) of the rectangular waveguide body (1), one end of the dielectric rod (5) extends out of the through holes, and one end, extending out of the through holes, of the dielectric rod (5) is connected with a driving mechanism (6).

2. The E-plane dielectric tunable waveguide filter of claim 1, wherein: at least two dielectric rods (5) are inserted into the resonant cavity (3) at the end part.

3. The E-plane dielectric tunable waveguide filter of claim 1, wherein: the material of the dielectric rod (5) is a dielectric with a certain dielectric constant, and comprises but not limited to one of plastic, quartz and ceramic.

4. The E-plane dielectric tunable waveguide filter of claim 1, wherein: all the dielectric rods (5) are arranged in a straight line shape or an S shape.

5. The E-plane dielectric tunable waveguide filter of claim 1, wherein: the coupling structure (2) is a plurality of coupling partition walls (21), and the coupling partition walls (21) are fixed in the rectangular waveguide body (1).

6. The E-plane dielectric tunable waveguide filter according to claim 5, wherein: the rectangular waveguide body (1) comprises a bottom groove (13), an E face of the bottom groove (13) is opened, an E panel (14) is connected to the opening of the bottom groove (13), a through hole is formed in the E panel (14), and a coupling partition wall (21) is fixed in the bottom groove (13).

7. The E-plane dielectric tunable waveguide filter of claim 1, wherein: the coupling structure (2) comprises two metal coupling diaphragms (22), the two metal coupling diaphragms (22) are sleeved in the rectangular waveguide body (1), and the metal coupling diaphragms (22) are parallel to the H surface of the rectangular waveguide body (1); the metal coupling membrane (22) is provided with a plurality of coupling strips (221), and the resonant cavity (3) is formed by separating the coupling strips (221) on the two metal coupling membranes (22).

8. The E-plane dielectric tunable waveguide filter of claim 7, wherein: the rectangular waveguide body (1) comprises two H-face grooves (15), an E panel (14) is connected between two ends of each H-face groove (15), a through hole is formed in one of the E panels (14), and two metal coupling diaphragms (22) are sleeved in a space surrounded by the two H-face grooves (15) and the two E panels (14).

9. An E-plane dielectric tunable waveguide filter according to any one of claims 1 to 8, wherein: the driving mechanism (6) is a linear motor.