KR101331775B1 - Waveguide low pass filter using rings and ridges - Google Patents

Abstract

Disclosed is a waveguide low-pass filter using rings and ridges for indicating improved pass and/or suppression properties in a specific frequency band. The waveguide low-pass filter comprises a waveguide (110) which has a rectangular parallelepiped shape, such that the inner part is formed to be narrower than the outer part, with a through hole in the longitudinal direction, the inside of the rectangular parallelepiped having a step shape; a ridge (120) which is installed in the longitudinal direction of the waveguide at the center of the inner lower surface of the waveguide and in which multiple protrusions are formed; and multiple rectangular rings (130) which are arranged to surround the multiple protrusions in a direction crossing the longitudinal direction of the ridge (120). As a result, the present invention has good performance in terms of reflection loss in a frequency band in which signals passes and insertion loss and isolation in a frequency band in which signals are suppressed.

Description

Waveguide Low Pass Filter Using Ring and Ridge {WAVEGUIDE LOW PASS FILTER USING RINGS AND RIDGES}

The present invention relates to low pass filters, and more particularly to waveguide low pass filters using rings and ridges that exhibit pass or suppression characteristics in a particular frequency band.

Generally, passing a certain frequency band out of many frequencies and blocking the passage of the remaining frequency bands is called a filter or filter.

Here, the range of the frequency passing through the filter is called a pass band, the frequency range that is blocked and not easily passed is called an attenuation band, and the frequency that is the boundary between the pass band and the attenuation band is called a cutoff frequency. At this time, the low pass filter has a frequency lower than the cutoff frequency as a pass band, and has a frequency higher than the cutoff frequency as an attenuation band.

On the other hand, an antenna system requires a low pass filter to remove low frequency ripple and high frequency spurious components of a signal, and to use the high frequency suppression and various detections.

As the structure of the low pass filter described above, a corrugated structure or an evanescent mode is used. In addition, the low pass filter improves existing structures such as a waffle iron type slotted in the corrugated structure or a corrugated structure with an impedance step to improve the pass band characteristics and the high frequency spurious characteristics. It was designed using plates.

However, the low pass filter with the conventional corrugated structure cannot predict the ripple characteristic in the pass band, and because it has the same impedance step, the insertion loss characteristic is weakened near the cutoff frequency, and sufficient attenuation of the harmonic component of the signal is achieved. There is an unexpected problem.

SUMMARY OF THE INVENTION An object of the present invention for solving the above problems is to provide a waveguide low pass filter using rings and ridges exhibiting improved pass or suppress characteristics at certain frequencies.

According to a low pass filter using a ring and a ridge according to an embodiment of the present invention for achieving the above object, has a rectangular parallelepiped shape is formed in the through hole in the longitudinal direction, the inside of the rectangular parallelepiped has a stepped shape The width of the waveguide 110 becomes narrower as it enters, and is provided along the longitudinal direction of the waveguide at the center of the inner lower surface of the waveguide, the ridge 120 having a plurality of protrusions formed therein, and the plurality of protrusions of the ridge ( It includes a plurality of rectangular rings 130 arranged to wrap in a direction crossing the longitudinal direction of the 120.

Here, the plurality of protrusions may have a symmetrical height with respect to the protrusions disposed in the center of the plurality of protrusions, and the height may be lowered toward the protrusions at both ends from the protrusion disposed at the center.

Here, the plurality of protrusions may be formed at regular intervals along the longitudinal direction of the ridge 120.

Here, the plurality of protrusions may have the same horizontal and vertical lengths on the upper surfaces of the protrusions.

Here, the plurality of rectangular rings 130 are arranged to surround odd or even protrusions of the plurality of protrusions in a direction crossing the longitudinal direction of the ridge 120, and the plurality of rectangular rings 130. The height of the left and right symmetry with respect to the rectangular ring disposed in the center of the can be lowered toward the protrusions at both ends relative to the protrusion disposed in the center.

Here, the plurality of rectangular rings 130 have a width (b) wider than the width (a) of the plurality of protrusions, except for the width of the rectangular ring disposed in the center of the plurality of rectangular rings 130. The width of the rectangular ring may be the same.

Here, the plurality of rectangular rings 130, the length (c) of each rectangular ring may be the same.

Here, the left and right side surfaces of the plurality of rectangular rings 130 may be coupled to be in contact with the narrowest inner surface of the waveguide.

According to the waveguide low pass filter using the ring and the ridge according to an embodiment of the present invention, a plurality of rectangular rings having different heights are coupled to a ridge structure and a ridge structure symmetrically arranged in a direction perpendicular to the lower frame.

Therefore, it can exhibit good performance in terms of reflection loss in the frequency band through which the signal passes, insertion loss in the frequency band in which the signal is suppressed, and isolation.

1 is a perspective view of a waveguide low pass filter having a ring and a ridge in accordance with an embodiment of the present invention.
2 is a perspective view of a waveguide low pass filter having a ring and a ridge partially cut away from an upper surface of the waveguide low pass filter.
3 is a side cross-sectional view showing a cross section taken along line II ′ of the waveguide low pass filter having a ring and a ridge shown in FIG. 1.
4 shows an exploded view of a waveguide low pass filter having a ring and a ridge in accordance with an embodiment of the present invention.
FIG. 5 is a graph illustrating filter characteristics of a waveguide low pass filter having only a ridge structure in FIG. 4.
6 is a graph showing filter characteristics of a waveguide low pass filter having a ring and a ridge according to an embodiment of the present invention.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail.

It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component. And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

When a component is referred to as being "connected" or "connected" to another component, it may be directly connected to or connected to that other component, but it may be understood that other components may be present in between. Should be. On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the relevant art and are to be interpreted in an ideal or overly formal sense unless explicitly defined in the present application Do not.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In order to facilitate the understanding of the present invention, the same reference numerals are used for the same constituent elements in the drawings and redundant explanations for the same constituent elements are omitted.

1 is a perspective view of a waveguide low pass filter having a ring and a ridge according to an embodiment of the present invention, and FIG. 2 is a perspective view of a waveguide low pass filter having a ring and a ridge partially cut away from an upper surface of the waveguide low pass filter.

1 and 2, the waveguide low pass filter 100 having a ring and a ridge according to an embodiment of the present invention has a shape of a rectangular parallelepiped having a through hole formed in a longitudinal direction, and the inside of the rectangular parallelepiped is a step. It includes a waveguide 110 having a shape that narrows the width as it enters the inside.

Specifically, the waveguide 110 has a three-stage (transformer) from the outside to the inside, and has a structure that forms a vertical symmetry to satisfy the transmission and reception characteristics.

In addition, as shown in FIG. 2, the waveguide low pass filter 100 is installed along the longitudinal direction of the waveguide 110 at the center of the inner surface of the waveguide 110 and includes a ridge 120 having a plurality of protrusions formed therein. do.

Here, the plurality of protrusions may have a symmetrical height with respect to the protrusions disposed at the center of the plurality of protrusions, and the height may be lowered toward the protrusions at both ends from the protrusion disposed at the center.

In addition, the waveguide low pass filter 100 includes a plurality of rectangular rings 130 arranged to surround the plurality of protrusions in a direction crossing the longitudinal direction of the ridge 120.

Here, the plurality of rectangular rings 130 are arranged to surround odd or even protrusions of the plurality of protrusions in a direction crossing the longitudinal direction of the ridge 120, and are disposed at the center of the plurality of rectangular rings 130. The height may be lowered toward the protrusions at both ends with respect to the protrusions disposed at the center with the height of left and right symmetry with respect to the rectangular ring.

As described above, by arranging the ridge inside the waveguide, the cutoff frequency can be reduced, and as a result, the waveguide low pass filter can be miniaturized. In addition, by arranging rectangular rings of different heights, resonance can be induced and improved pass and / or suppression characteristics can be exhibited at specific frequencies.

3 is a side cross-sectional view showing a cross section taken along line II ′ of the waveguide low pass filter having a ring and a ridge shown in FIG. 1.

Referring to FIG. 3, the waveguide low pass filter 100 having a ring and a ridge according to an embodiment of the present invention may include a waveguide 110, a ridge 120, and a plurality of rectangular rings 130.

The waveguide 110 has a rectangular parallelepiped shape in which a through hole is formed in a longitudinal direction, and has a structure in which the width of the rectangular parallelepiped is narrowed as it enters the inside.

Specifically, the waveguide 110 has a three-stage (transformer) from the outside to the inside, and has a structure that forms a vertical symmetry to satisfy the transmission and reception characteristics.

Here, the waveguide 110 may have a length of substantially 100mm along the length direction, the width may be substantially 28.5mm.

The ridge 120 is installed along the longitudinal direction of the waveguide 110 at the center of the lower surface of the waveguide 110, and a plurality of protrusions are formed.

Here, the plurality of protrusions may have a symmetrical height with respect to the protrusions disposed in the center of the plurality of protrusions, and the height of the protrusion may be lowered toward the protrusions at both ends from the protrusion disposed at the center.

In addition, the plurality of protrusions may be formed at equal intervals along the longitudinal direction of the ridge 120, and each of the protrusions may have the same width.

In addition, the horizontal and vertical lengths of the upper surfaces of each of the plurality of protrusions may be configured to be the same. For example, the horizontal and vertical lengths of the upper surfaces of each of the plurality of protrusions may be substantially equal to 2 mm.

The plurality of rectangular rings 130 are disposed to surround the plurality of protrusions in a direction crossing the longitudinal direction of the ridge 120.

In addition, the plurality of rectangular rings 130 are disposed to surround odd or even protrusions of the plurality of protrusions, and have a height of left and right symmetry with respect to a rectangular ring disposed at the center of the plurality of rectangular rings 130. The height of the protrusion may be lowered toward the protrusion at both ends with respect to the protrusion disposed at the center.

Here, the upper and lower side surfaces of the rectangular ring disposed in the center of the plurality of rectangular rings 130 may be coupled to be in contact with the inner surface of the waveguide 110, and the height between the upper and lower sides of the rectangular ring may be substantially 10.16 mm. have.

In addition, the plurality of rectangular rings 130 has a width (see b of FIG. 4) wider than the width of the plurality of protrusions (see a of FIG. 4), and is disposed in the center of the plurality of rectangular rings 130. The width of the remaining rectangular rings can be the same except for the width of the ring.

In addition, the lengths of the rectangular rings (see c of FIG. 4) may be the same in a direction crossing the plurality of rectangular rings 130 and the ridges 120.

In addition, the left and right side surfaces of the plurality of rectangular rings 130 may be coupled to contact the narrowest inner surface of the waveguide. For example, the distance between the left and right sides of the plurality of rectangular rings 130 in contact with the highest inner side of the waveguide may be substantially 22.86 mm.

According to the waveguide low pass filter 100 using the ring and the ridge according to an embodiment of the present invention, the loss in the frequency band through which the signal is passed, the insertion loss in the frequency band at which the signal is suppressed, and the isolation are good. It can indicate performance.

Figure 4 shows a ridge and a ring installed inside a waveguide low pass filter having a ring and a ridge in accordance with an embodiment of the present invention.

Referring to FIG. 4, the ridge 120 is installed along the longitudinal direction of the waveguide (110 of FIG. 1) at the center of the lower surface of the waveguide (110 of FIG. 1), and a plurality of protrusions are formed.

Here, the plurality of protrusions are formed in a direction perpendicular to the upper surface of the ridge 120, have a symmetrical height with respect to the protrusions disposed in the center of the plurality of protrusions, and at both ends from the protrusions disposed in the center. The height can be lowered toward the overhang.

Specifically, the height of the protrusions disposed in the center of the plurality of protrusions may be substantially 6 mm, and the remaining protrusions may have a height of 6 mm, 5 mm, 3 mm, and 1 mm in symmetrical directions with respect to the 6 mm height protrusion.

In addition, the plurality of protrusions may be formed at equal intervals along the longitudinal direction of the ridge 120. For example, the plurality of protrusions may be formed at equal intervals of substantially 3.2 mm along the longitudinal direction of the ridge 120.

In addition, the horizontal and vertical lengths of the upper surfaces of the plurality of protrusions may be the same. For example, the horizontal and vertical lengths of the top surfaces of each of the plurality of protrusions may have substantially the same length as 2 mm.

The plurality of rectangular rings 130 are arranged to surround odd or even protrusions of the plurality of protrusions in a direction crossing the longitudinal direction of the ridge 120, and a rectangular ring disposed at the center of the plurality of rectangular rings 130. It can be configured to have a height of left and right symmetry with respect to the protrusions disposed in the center toward the protrusions at both ends of the height.

Specifically, the height of the rectangular ring disposed in the center of the plurality of rectangular rings 130 may be substantially 10.16mm, and the remaining rectangular rings have a height of 9.11 mm and 6.41 mm, respectively, symmetrically based on the height of 10.16 mm. Each can have.

In addition, the length c of each rectangular ring may be the same. For example, the plurality of rectangular rings 130 are disposed in a direction crossing the ridge 120, and each of the plurality of rectangular rings 130 may have a length of substantially 22.86 mm.

Here, the length of each of the plurality of rectangular rings 130 may be equal to the length between the narrowest inner surfaces of the waveguide (110 of FIG. 1).

In addition, the plurality of rectangular rings 130 may have a width (b) wider than the width (a) of the plurality of protrusions, the remaining rectangles except for the width of the rectangular ring disposed in the center of the plurality of rectangular rings 130 The width of the rings may be the same.

For example, the width of the center rectangular ring of the plurality of rectangular rings 130 may be substantially 2.8 mm, and the width of the remaining rectangular rings may be substantially 3 mm.

FIG. 5 is a graph showing filter characteristics of the waveguide low pass filter having only the ridge structure 120 of FIG. 4.

Referring to FIG. 5, in the waveguide low pass filter having only the ridge 120 structure of FIG. 4, a signal is passed through a frequency of 7.25 GHz to 8.4 GHz and a 12.25 GHz to 14.5 GHz section (Ku-band). Signal is suppressed.

Here, the waveguide low pass filter having only the ridge 120 structure has a return loss of 19.5 dB or more in the frequency band through which the signal is passed, and an insertion loss in the frequency band in which the signal is suppressed is 0.4. Below dB, the isolation for Ku-band is more than 60 dB.

6 is a graph showing filter characteristics of a waveguide low pass filter having a ring and a ridge according to an embodiment of the present invention.

Referring to FIG. 6, the waveguide low pass filter having a ring and a ridge has a signal passing through a frequency of 7.25 GHz to 8.4 GHz and a signal suppressed from a 12.25 GHz to 14.5 GHz. .

Here, the waveguide lowpass filter with ring and ridge has a return loss of more than 36.5 dB in the frequency band through which the signal is passed, an insertion loss of less than 0.1 dB in the frequency band where the signal is suppressed, and an isolation degree for the Ku-band. It has a characteristic that satisfies 79.5 dB or more.

Therefore, according to the waveguide low pass filter having a ring and ridge according to an embodiment of the present invention compared to the waveguide low pass filter having only the ridge structure 410 of FIG. The loss is 0.3 dB and the isolation for Ku-band is 19.5 dB.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined in the appended claims. It will be possible.

100: waveguide low pass filter 110: waveguide
120: ridge 130: rectangular ring

Claims (8)

A waveguide having a shape of a rectangular parallelepiped having a through hole formed in a longitudinal direction, the width of the rectangular parallelepiped being narrowed as the inside thereof enters a stepped shape;
A ridge (120) disposed along a longitudinal direction of the waveguide at a center of an inner lower surface of the waveguide and having a plurality of protrusions formed therein; And
A waveguide low pass filter (100) comprising a plurality of rectangular rings (130) arranged to surround the plurality of protrusions in a direction crossing the longitudinal direction of the ridge (120). The method according to claim 1,
The plurality of protrusions,
Waveguide low pass filter (100) having a height of symmetry based on the protrusions disposed in the center of the plurality of protrusions, the height is lowered toward the protrusions at both ends from the protrusions disposed in the center. The method according to claim 1,
The plurality of protrusions,
Waveguide low pass filter (100), characterized in that formed at regular intervals along the longitudinal direction of the ridge (120). The method according to claim 1,
The plurality of protrusions,
Waveguide low pass filter (100), characterized in that the same horizontal and vertical length of the upper surface of each of the protrusions. The method according to claim 1,
The plurality of rectangular rings 130,
The odd-numbered or even-numbered protrusions of the plurality of protrusions are disposed to wrap in a direction crossing the longitudinal direction of the ridge 120, and are symmetrically symmetrically based on a rectangular ring disposed at the center of the plurality of rectangular rings 130. Waveguide low pass filter 100, characterized in that the height is lowered toward the protrusions at both ends on the basis of the protrusion is disposed in the center with a height of. The method according to claim 5,
The plurality of rectangular rings 130,
A waveguide low pass having a width (b) wider than the width (a) of the plurality of protrusions, except for the width of the rectangular ring disposed in the center of the plurality of rectangular rings (130). Pass Filter 100. The method according to claim 1,
The plurality of rectangular rings 130,
Waveguide low pass filter (100), characterized in that the length (c) of each rectangular ring is the same. The method of claim 7,
A waveguide low pass filter (100), characterized in that the left and right side surfaces of the plurality of rectangular rings (130) are coupled to be in contact with the narrowest inner surface of the waveguide.

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