CN104916888A - High-power filter - Google Patents

Abstract

The present invention proposes a high-power filter, which is an interdigitated filter and is composed of two groups of parallel coupled line resonator arrays intersecting each other; the resonator is an aluminum rod resonant rod that is directly short-circuited at one end and loaded with a flat capacitor at the other end; A hole is drilled in the middle of the resonator rod, and a tuning screw is added from the top of the cavity, and the resonant frequency of the resonator is changed by adjusting the depth of the tuning screw. In the high-power filter of the present invention, the part where the tuning screw goes deep into the resonant rod is fully wrapped with a medium, which greatly increases the power capacity of the filter; moreover, it solves the problem of gaps caused by different linear expansion coefficients of different materials due to temperature changes; the medium can As the tuning screw moves up and down, it is easy to tune the filter.

Description

A high power filter

technical field

The invention relates to the microwave field, in particular to a microwave filter.

Background technique

Microwave filters are widely used in microwave communication, radar navigation, electronic countermeasures, satellite relay, missile guidance, test instruments and other systems, and are indispensable devices in microwave and millimeter wave systems. Nowadays, higher requirements are put forward for high power, miniaturization and light weight of filters.

In order to realize a small-volume, high-power cavity filter, a design scheme that fills the resonator cavity with a dielectric to increase the breakdown field strength inside the filter has been proposed in the past. As shown in Figure 1, adding a medium between the resonant rod and the tuning screw, the breakdown field strength of the medium is much stronger than that of air, thereby increasing the power capacity of the filter.

The electric field in the filter is mainly concentrated around and at the bottom of the tuning screw in the resonant cavity. In the prior art, the bottom of the tuning screw is not protected by a dielectric layer, and the degree of power capacity increase is limited. At the same time, the medium is filled between the tuning screw and the resonant cavity. When the tuning screw is used to tune the filter, as the tuning screw rotates up and down, a gap is formed between the tuning screw and the medium, and the field strength in the gap will increase sharply. High, causing the filter to burn out quickly.

Contents of the invention

In order to solve the defects and deficiencies in the prior art, the present invention proposes a high-power filter that uses a tuning screw that seamlessly connects the medium and the metal for tuning.

Technical scheme of the present invention is realized like this:

A high-power filter, which is an interdigitated filter, is composed of two groups of parallel coupled line resonator arrays intersecting each other; the resonator is an aluminum rod resonant rod that is directly short-circuited at one end and loaded with a flat capacitor at the other end; Holes, add tuning screws from the top of the cavity, and change the resonant frequency of the resonator by adjusting the depth of the tuning screws. The part of the tuning screw that goes deep into the resonant rod is completely wrapped with a medium that has a linear expansion coefficient and a material similar to that of the tuning screw, forming a dielectric layer. The tuning screw and the medium are glued and molded to ensure a seamless connection between the two.

Optionally, the tuning screw is made of metal material aluminum.

Optionally, the medium is made of polyphenylene ether with 30% glass fiber added.

Optionally, the part where the tuning screw goes deep into the resonant rod is fully wrapped with a medium with a linear expansion coefficient similar to that of the material of the tuning screw.

Optionally, the seamless connection between the tuning screw and the dielectric layer is formed by applying glue and molding.

Optionally, the thickness of the dielectric layer is one-third of the distance between the cavities.

The beneficial effects of the present invention are:

(1) Wrap all the tuning screws, greatly increasing the power capacity of the filter;

(2) Solve the gap problem caused by different linear expansion coefficients of different materials due to temperature changes;

(3) The medium can move up and down with the tuning screw, which facilitates the tuning of the filter.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

Fig. 1 is the structural schematic diagram of existing microwave filter;

Fig. 2 is a schematic structural diagram of the high-power filter of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The present invention proposes a high-power filter that is tuned using a tuning screw that is seamlessly connected between the medium and the metal. As shown in Figure 2, the present invention is an interdigitated filter consisting of two sets of parallel coupled line resonator arrays intersecting each other composition. The resonator is directly short-circuited at one end, and the other end is an aluminum rod resonant rod loaded with a flat capacitor. A hole is drilled in the middle of the resonator rod, and a tuning screw is added from the top of the cavity, and the resonant frequency of the resonator is changed by adjusting the depth of the tuning screw. The tuning screw is made of metal material, preferably aluminum, and the part of the tuning screw that penetrates into the resonant rod is fully wrapped with a medium with a linear expansion coefficient similar to that of aluminum to form a dielectric layer.

The medium uses a material with a linear expansion coefficient similar to that of aluminum, preferably polyphenylene ether with 30% fiber added. Using glue coating and molding technology to make the two materials seamlessly connected. At this time, the electric field of the filter is basically concentrated in the medium, which enhances the power capacity of the filter. At the same time, because the expansion coefficients of the two materials are similar, the gap between the tuning screw and the medium is solved due to temperature changes, and the electric field intensity between the gap increases and the problem of rapid ignition is solved.

Preferably, the thickness of the dielectric layer is one-third of the distance between the cavities, and at this time the power capacity of the filter is maximum.

The high-power filter of the present invention wraps all the tuning screws, greatly increasing the power capacity of the filter; moreover, it solves the problem of gaps caused by different linear expansion coefficients of different materials due to temperature changes; the medium can move up and down with the tuning screws, Easy to tune the filter.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of the present invention. within the scope of protection.

Claims (6)

1. a high power filter, is characterized in that, is interdigital filter, is mutually intersected form by two groups of parallel coupled line resonator battle arrays; Resonator is that one end direct short-circuit, in addition one end use the aluminium bar resonant rod that capacity plate antenna loads; Punching in the middle of resonant rod, tuning screw is added from the top of cavity, by the resonance frequency regulating the degree of depth of tuning screw to change resonator, the seamless parcel of medium that the part that tuning screw gos deep into resonant rod uses linear expansion coefficient and tuning screw material to be similar to, forms dielectric layer.

2. a kind of high power filter as claimed in claim 1, is characterized in that, described tuning screw uses metallic material of aluminum to make.

3. a kind of high power filter as claimed in claim 2, is characterized in that, the seamless parcel of Noryl gluing mold pressing that the part that tuning screw gos deep into resonant rod uses linear expansion coefficient and aluminium to be similar to, and forms dielectric layer.

4. a kind of high power filter as claimed in claim 3, is characterized in that, adds the glass fibre of 30% in polyphenylene oxide.

5. a kind of high power filter as claimed in claim 1, by gluing, mold pressing, forms the seamless link between tuning screw and dielectric layer.

6. a kind of high power filter as claimed in claim 1, is characterized in that, described thickness of dielectric layers is three point one of chamber spacing.