WO2013026339A1

WO2013026339A1 - Elliptic function-type low-pass filter and communication cavity component employing same

Info

Publication number: WO2013026339A1
Application number: PCT/CN2012/079075
Authority: WO
Inventors: 郭春波; 邸英杰; 党志南; 昌敏华
Original assignee: 京信通信系统（中国）有限公司
Priority date: 2011-08-24
Filing date: 2012-07-24
Publication date: 2013-02-28
Also published as: CN102354778A; CN102354778B; BR112014004010A2

Abstract

Disclosed is mainly an elliptic function-type low-pass filter, which is arranged in a metal cavity. The metal cavity is provided with multiple sub-cavities connected sequentially. A resonant column is provided between two adjacent cavities. The resonant columns are provided on top thereof with a conductor rod. The conductor rod is provided with through holes at where each resonant column corresponds to. The resonant columns are each provided with a tuning screw passing through the corresponding through hole and penetrating deeply into the resonant column to allow capacitive coupling between the tuning screw and the resonant column. Two ends of the conductor rod respectively form two connection ports. The elliptic function-type low-pass filter of the present invention has great electrical specifications, a novel and unique structure, and is convenient for processing and mass production. A communication cavity component formed by employing the filter is capable of generating improved out-of-band rejection within an expanded range of frequency bands, thus meeting the requirement for increased degree of isolation between communication systems.

Description

Elliptic function type low-pass filter path and communication cavity device using same

Technical field

The invention relates to a communication cavity device for low-pass filtering a communication signal, in particular to an elliptic function type low-pass filter path.

Background technique

With the development of triple play and the enabling of the LTE band, the new frequency band is moving in both lower and higher directions than the traditional frequency band. With the introduction of new standards or systems, the market is increasingly demanding passive components.

For low-pass filters, the traditional implementation is generally Chebyshev type, such as the common sugar gourd-shaped low-pass filter, which has the advantages of simple structure and easy implementation, but the disadvantage is that the out-of-band drop is slow and the out-of-band suppression is The consistency of the low filter characteristics depends on the accuracy of the machining and assembly. Such low-pass filters are often used to suppress out-of-band bands, and in general, they do not meet the high isolation requirements between actual systems.

technical problem

Therefore, the primary object of the present invention is to overcome the above-mentioned deficiencies, and to provide an elliptical function type low-pass filter path which is faster in out-of-band and has a higher out-of-band suppression and is easy to process and produce.

Another object of the present invention is to provide a communication cavity device such as a combiner/duplexer/filter including the elliptic function type low pass filter path.

Technical solution

In order to achieve the object of the present invention, the present invention adopts the following technical solutions:

The elliptical function type low-pass filter path of the present invention is disposed in a metal cavity, wherein the metal cavity is provided with a plurality of sub-cavities that are sequentially connected, and a resonance column is disposed between two adjacent sub-chambers, above the resonance column Conductor rods are provided, and the conductor rods are provided with through holes corresponding to each of the resonant columns, and each of the resonant columns has a tuning screw passing through the corresponding through holes and deep into the resonant column to capacitively couple the tuning screw with the resonant column, the conductor Two connection ports are formed at both ends of the rod.

The combiner/duplexer/filter or the like of the present invention includes the aforementioned elliptic function type low pass filter path.

Beneficial effect

Compared with the prior art, the present invention has the following advantages: the elliptic function low-pass filter path of the present invention is based on a conventional sugar-gourd-shaped low-pass filter, and the low-impedance portion is replaced by an equivalent inductance. The resonator in series with the capacitor is incorporated into the main path. The equivalent inductance of the resonator is realized by the high impedance formed between the resonator column and the cavity wall. The equivalent capacitance is realized by the gap coupling between the tuning screw and the inner wall of the resonator column. The communication cavity device thus formed has a faster out-of-band degradation and can generate strong suppression in a wide frequency range outside the band, thereby satisfying the requirement of high isolation between communication systems; and at the same time, having small insertion loss, The invention has the advantages of small standing wave ratio, low passive intermodulation and large power capacity. In addition, the structure is novel and unique but not complicated, easy to process, low in precision for processing and assembly, and has very good consistency and is easy to produce.

DRAWINGS

1 is a schematic rear view of an elliptical function low-pass filter path of the present invention;

Figure 2 is a more detailed disclosure of the assembly relationship between the components on the basis of Figure 1;

FIG. 3 further discloses the assembly relationship between the resonant column, the conductor bar, the dielectric sleeve, and the tuning screw based on the foregoing figures.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the invention

The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

Referring to FIG. 1, the elliptic function type low-pass filter path of the present invention is designed and formed in a metal cavity 1, and mainly includes a plurality of sub-cavities 11-15 formed in the metal cavity 1, and is disposed in two adjacent sub-cavities. a ridge 10 at an intermediate portion between 11-15 and a resonant column 32 standing above the ridge 10, a conductor rod 4 traversing the longitudinal direction of the metal cavity 1 in the metal cavity 1 and placed above the resonant column 32 And a plurality of tuning screws 31 that are capacitively coupled to each of the resonant columns 32 through the conductor bars 4, and two

connection ports

21, 22 formed by connecting the two ends of the conductor bars 4. Of course, a cover body should be provided above the metal cavity 1, which is omitted because it is common knowledge.

Please further refer to FIG. 2 and FIG. 3 for a clearer understanding of the specific structure of the embodiment.

The plurality of sub-cavities 11-15 are arranged substantially in the same direction (straight line), and the spatial volume of the sub-cavities 11-15 is realized according to the design of the electrical performance index. Preferably, the two sub-cavities are separated from the first and the last. The spatial volumes of 11 and 15 are relatively small, and the remaining sub-cavities 12-14 in the intermediate section have substantially the same or similar spatial volume, which can be considered as equal.

The connection between the adjacent two adjacent sub-cavities 11-15 is a window opening structure, and at the window opening portion, the bottom wall of the metal cavity 1 is provided with a ridge 10 above the bottom wall, at which the ridge 10 is One of the resonant columns 32 is erected. The different ridges 10 are adapted to different frequency bands and have different heights. Thereby, a plurality of resonant columns 32 arranged along the same straight line are formed, and these resonant columns 32 together with the fenestration structure form an equivalent inductance in the aforementioned equivalent inductance-capacitor series resonator.

The two ends of the conductor bar 4 are respectively connected to the inner conductors (not shown) of the two

connection ports

21, 22, and the two

connection ports

21, 22 are fixed on the metal cavity 1, and the conductor bars 4 are thus It is fixed above each of the resonance columns 32. The conductor bars 4 are linear, the body of which presents a smaller diameter, and which is provided with a partial section 40 at a position corresponding to each of the resonator columns 32, the partial section 40 having a larger diameter. The diameter of the partial section 40 is larger than the diameter of the body in order to provide the through hole 41 for the tuning screw 31 to pass through.

In order to achieve capacitive coupling of each of the tuning screws 31 across the radial direction of the conductor bars 4 with the respective resonant columns 32, a threaded passage is provided radially at each of the larger diameter partial sections 40 of the conductor bars 4. The hole 41, and the resonator column 32 is provided with a slot 320 for the axial direction of the tuning screw 31. Thus, after a tuning screw 31 passes through a through hole 41 in the conductor bar 4 and penetrates into the slot 320 of the resonator column 32 corresponding to the position of the through hole 41, the tuning screw 31 and the corresponding resonant column 32 can be realized. Capacitive coupling between. In order to ensure insulation between the tuning screw 31 and the resonant column 32, a dielectric sleeve 30 made of Teflon or other insulating material is placed around the periphery of the tuning screw 31.

It can be seen from the above description that after the plurality of tuning screws 31 respectively pass through the corresponding plurality of through holes 41 of the conductor bar 4, respectively, the resonant columns 32 corresponding to the positions are capacitively coupled, and the capacitive coupling is the foregoing. The equivalent capacitance in the series capacitor of the inductor and capacitor.

Thus, the series connection of the corresponding equivalent inductance and equivalent capacitance constitutes an equivalent series resonator. Multiple equivalent series resonators are combined to enable the low-pass filter path to produce higher rejection (above 70%) over a wide band of out-of-band (relative bandwidth up to 45%).

In another embodiment not shown in the present invention, the arrangement of the plurality of sub-cavities 11-15 may not be in the same direction (straight line), for example, the arrangement direction of the plurality of sub-cavities 11-15 forms a right angle. As a result of the adaptation, the conductor bars 4 also need to be designed to be bent. It can be seen that appropriately changing the structure of the individual components of the present invention does not affect the achievement of the technical effects of the present invention.

By applying the elliptic function type low-pass filter path of the present invention to a combiner, a duplexer or a filter, the performance of high bandwidth and high suppression can be better exerted.

While the present invention has been described with respect to the above embodiments, those skilled in the art, after reading the present specification, in conjunction with common general knowledge, should be able to conceive more specific embodiments, but such specific embodiments do not depart from the present invention. In the spirit of the claims, any form of equivalent or simple modification is considered to be an embodiment encompassed by the present invention.

Industrial applicability

Sequence table free content

Claims

An elliptical function type low-pass filter path is disposed in the metal cavity, wherein the metal cavity is provided with a plurality of sub-cavities that are sequentially connected, and a resonance column is disposed between the adjacent two sub-cavities. A conductor bar is arranged above the resonance column, and a conductor hole is provided with a through hole corresponding to each of the resonance columns, and each of the resonance columns has a tuning screw passing through the corresponding through hole and deepening the resonance column to make the tuning screw and the resonance column capacitive. Coupling, two connecting ports are formed at two ends of the conductor bar.
The elliptic function type low-pass filter path according to claim 1, wherein the plurality of sub-cavities are arranged in the same direction, and the conductor bars are correspondingly linear.
The elliptic function type low-pass filter path according to claim 1, wherein the plurality of sub-cavities are not arranged in the same direction, and the conductor bars are correspondingly bent.
The elliptic function type low-pass filter path according to any one of claims 1 to 3, characterized in that a dielectric sleeve is provided between the tuning screw and the resonant column.
The elliptic function type low-pass filter path according to any one of claims 1 to 3, characterized in that the diameter of the partial section around the through hole 41 of the conductor bar is larger than the diameter of the conductor bar main body.
The elliptic function type low-pass filter path according to any one of claims 1 to 3, characterized in that a ridge is provided between the resonator column and the bottom wall of the metal cavity.
The elliptic function type low-pass filter path according to claim 6, wherein heights of respective ridge portions corresponding to the respective resonance columns are different.
The elliptic function type low-pass filter path according to any one of claims 1 to 3, wherein among the plurality of sub-cavities, the remaining sub-cavities between the first and the last sub-chambers are equally large.
A combiner/duplexer/filter comprising the elliptic function type low pass filter path according to any one of claims 1 to 8.