JP2800478B2 - Microwave filter - Google Patents

Microwave filter

Info

Publication number
JP2800478B2
JP2800478B2 JP3180868A JP18086891A JP2800478B2 JP 2800478 B2 JP2800478 B2 JP 2800478B2 JP 3180868 A JP3180868 A JP 3180868A JP 18086891 A JP18086891 A JP 18086891A JP 2800478 B2 JP2800478 B2 JP 2800478B2
Authority
JP
Japan
Prior art keywords
wavelength
band
frequency
band frequency
stubs
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
JP3180868A
Other languages
Japanese (ja)
Other versions
JPH0529803A (en
Inventor
博 阪
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panasonic Corp
Panasonic Holdings Corp
Original Assignee
Panasonic Corp
Matsushita Electric Industrial Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Panasonic Corp, Matsushita Electric Industrial Co Ltd filed Critical Panasonic Corp
Priority to JP3180868A priority Critical patent/JP2800478B2/en
Priority to US07/916,252 priority patent/US5291161A/en
Publication of JPH0529803A publication Critical patent/JPH0529803A/en
Application granted granted Critical
Publication of JP2800478B2 publication Critical patent/JP2800478B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Landscapes

  • Control Of Motors That Do Not Use Commutators (AREA)

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【0001】[0001]

【産業上の利用分野】本発明はストリップ線路またはマ
イクロストリップ線路を用いたマイクロ波フィルタに関
し、特に阻止域周波数が通過域周波数の両側に隣接して
存在し、かつ、通過域周波数、阻止域周波数ともに帯域
幅が有限な場合の帯域通過型のマイクロ波フィルタの構
成に関するものである。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microwave filter using a strip line or a microstrip line, and more particularly to a microwave filter having a stop band frequency adjacent to both sides of a pass band frequency, and having a pass band frequency and a stop band frequency. Both relate to the configuration of a band-pass type microwave filter when the bandwidth is finite.

【0002】[0002]

【従来の技術】ある帯域の信号のみを取りだし、それ以
外の信号を除去したい場合にはフィルタがよく用いられ
る。特に取り出したい信号の周波数が除去したい信号の
周波数に挟まれている場合、すなわち阻止域周波数が通
過域周波数の高域側と低域側の両側に隣接して存在する
場合には、帯域通過フィルタが用いられる。
2. Description of the Related Art A filter is often used when only a signal in a certain band is to be extracted and other signals are to be removed. In particular, when the frequency of the signal to be extracted is sandwiched between the frequencies of the signal to be removed, that is, when the stop band frequency exists adjacent to both the high band side and the low band side of the pass band frequency, the band pass filter is used. Is used.

【0003】(図5)に従来例による帯域通過フィルタ
の構成例を示す。この帯域通過フィルタは両端が開放さ
れた半波長ストリップ線路を共振器として用いたもの
で、入力端子1、出力端子2との間で入力ストリップ線
路3、出力ストリップ線路4および半波長ストリップ線
路共振器5が1/4波長の長さにわたって、隣接する半波
長ストリップ線路共振器と逐次分布結合して構成された
ものである。
FIG. 5 shows an example of the configuration of a conventional band-pass filter. This band-pass filter uses a half-wave strip line having both ends open as a resonator, and has an input strip line 3, an output strip line 4, and a half-wave strip line resonator between an input terminal 1 and an output terminal 2. Numeral 5 is formed by sequentially distributed coupling with an adjacent half-wavelength strip line resonator over a length of 1/4 wavelength.

【0004】[0004]

【発明が解決しようとする課題】以上述べた従来例で
は、フィルタの構成要素である半波長ストリップ線路共
振器5の段数を増やすことでフィルタの帯域外特性を急
峻にすることができる。
In the conventional example described above, the out-of-band characteristic of the filter can be made sharp by increasing the number of stages of the half-wavelength strip line resonator 5 which is a component of the filter.

【0005】しかし、この半波長ストリップ線路共振器
5の無負荷Q値は高くなく、10GHzでは数百程度である
ためフィルタの段数を増やすと、フィルタ寸法が大きく
なるとともに通過域での挿入損失が増大する。従って、
通過域での挿入損失が小さく帯域外特性の急峻なフィル
タを得ることは困難である。
However, the unloaded Q value of the half-wavelength stripline resonator 5 is not high, and is several hundreds at 10 GHz. Therefore, if the number of filter stages is increased, the filter size becomes large and the insertion loss in the pass band is reduced. Increase. Therefore,
It is difficult to obtain a filter having a small out-of-band characteristic with a small insertion loss in the pass band.

【0006】本発明はかかる点に鑑みてなされたもの
で、簡単な構成で上記従来例のもつ欠点を除去し、通過
帯域では挿入損失が小さく、阻止帯域では挿入損失が十
分に大きく、阻止帯域から通過帯域へ移行する領域では
挿入損失の急峻な立ち上がり特性を有する帯域通過型の
マイクロ波フィルタを提供することを目的とする。
The present invention has been made in view of the above points, and eliminates the disadvantages of the above-described conventional example with a simple configuration. The insertion loss is small in the pass band, the insertion loss is sufficiently large in the stop band, and the stop band is small. It is an object of the present invention to provide a band-pass type microwave filter having a steep rising characteristic of an insertion loss in a region which shifts from a pass band to a pass band.

【0007】[0007]

【課題を解決するための手段】上記課題を解決するため
に本発明のマイクロ波フィルタは主線路に間隔がそれぞ
れL0,L0',L0"(=L0または≒L0)でもって順次並
列に設けられた長さがそれぞれL1,L2,L3,L4の第
1,第2,第3および第4の終端開放スタブで構成さ
れ、それらの4本の終端開放スタブの中で第2,第3の
2本の終端開放スタブの長さを通過帯域よりも高域側に
ある阻止域周波数のほぼ1/4波長の長さに選び、残りの
第1,第4の2本の終端開放スタブの長さを通過帯域よ
りも低域側にある阻止域周波数のほぼ1/4波長の長さに
選ぶとともに、2L0'<L2≒L3<L1≒L4<L0<2L
1の条件を満足するか、あるいは2L0'<L2=L3<L1
=L4<L0<2L1の条件を満足するように、L0
0',L1,L2,L3,L4の長さを選んだ構成としてい
る。
In order to solve the above-mentioned problems, a microwave filter according to the present invention has main lines having intervals of L 0 , L 0 ′, L 0 ”(= L 0 or ≒ L 0 ), respectively. first sequential parallel each length L 1 provided, L 2, L 3, L 4, is constituted by the second, third and fourth open-ended stub, four open-ended stubs thereof In which the length of the second and third open-ended stubs is selected to be approximately 1 wavelength of the stop band frequency higher than the pass band, and the remaining first and fourth stubs are selected. The length of the two open-end stubs is selected to be approximately 1 wavelength of the stop band frequency lower than the pass band, and 2L 0 ′ <L 2 ≒ L3 <L 1 ≒ L 4 < L 0 <2L
1 or 2L 0 ′ <L 2 = L 3 <L 1
= L 4 <L 0 <2L 1 so that L 0 ,
The lengths L 0 ′, L 1 , L 2 , L 3 and L 4 are selected.

【0008】[0008]

【作用】本発明によれば、上記した構成により、通過帯
域では挿入損失が小さく、阻止帯域では挿入損失が十分
に大きく、阻止帯域から通過帯域へ移行する領域では挿
入損失の急峻な立ち上がり特性を有するとともに、通過
帯域および阻止帯域とも有限な帯域幅を有する帯域通過
型のマイクロ波フィルタが得られる。
According to the present invention, with the above-described configuration, the insertion loss is small in the pass band, the insertion loss is sufficiently large in the stop band, and the steep rise characteristic of the insertion loss is obtained in the region where the transition from the stop band to the pass band occurs. Thus, a band-pass type microwave filter having a finite bandwidth in both the pass band and the stop band is obtained.

【0009】[0009]

【実施例】(図1)は本発明による第1の実施例である
帯域通過型のマイクロ波フィルタで、入力端子11および
出力端子12をストリップ線路で構成される主線路13で結
び、主線路13に長さがそれぞれL1,L2,L3,L4の終
端開放スタブ14,15,16,17をそれぞれ間隔L0
0',L0でもって順次並列に接続している。
FIG. 1 shows a band-pass type microwave filter according to a first embodiment of the present invention, in which an input terminal 11 and an output terminal 12 are connected by a main line 13 composed of a strip line. length respectively 13 L 1, L 2, L 3, L respectively distance L 0 termination open stub 14, 15 of 4,
L 0 ′ and L 0 are sequentially connected in parallel.

【0010】終端開放スタブ14,17の長さL1,L4は通
過帯域よりも低域側にある阻止域周波数の帯域内あるい
は帯域近傍に減衰極がくるように阻止域周波数の1/4波
長あるいはほぼ1/4波長の長さに選ぶ。そして終端開放
スタブ15,16の長さL2,L3は通過帯域よりも高域側に
ある阻止域周波数の帯域内あるいは帯域近傍に減衰極が
くるように阻止域周波数の1/4波長あるいはほぼ1/4波長
の長さに選ぶ。
The lengths L 1 and L 4 of the open-end stubs 14 and 17 are set to 1/4 of the stop band frequency so that the attenuation pole comes within or near the stop band frequency lower than the pass band. Choose a wavelength or approximately 1/4 wavelength length. The lengths L 2 and L 3 of the open-ended stubs 15 and 16 are set to 1/4 wavelength of the stop band frequency so that the attenuation pole comes within or near the band of the stop band frequency higher than the pass band. Choose about 1/4 wavelength length.

【0011】そしてL0,L0',L1,L2,L3,L4
長さは2L0'<L2≒L3<L1≒L4<L0<2L1の条件を
満足するか、あるいは2L0'<L2=L3<L1=L4<L0
<2L 1の条件を満足するように選ぶと同時に、間隔L0
に対しては通過域周波数の6/16波長よりも長く、8/16波
長よりも短くなるように選び、L0'に対しては通過域周
波数の2/16波長よりも短くなるように選び、L0+L0'
に対しては通過域周波数の1/4波長前後の長さに選んで
いる。
And L0, L0', L1, LTwo, LThree, LFourof
Length is 2L0'<LTwo≒ LThree<L1≒ LFour<L0<2L1The condition
Satisfied or 2L0'<LTwo= LThree<L1= LFour<L0
<2L 1At the same time as satisfying the condition0
Is longer than the 6/16 wavelength of the passband frequency,
Choose to be shorter than the length, L0'Around the passband for
Select so that it is shorter than 2/16 wavelength of the wave number.0+ L0'
For the length of the passband frequency
I have.

【0012】(図2)は(図1)において、ストリップ
線路用誘電体基板の比誘電率を2.5、主線路13の特性イ
ンピーダンスZ0を50オーム、終端開放スタブ14,15,16,
17の特性インピーダンスZsをすべて90オームとした場合
に、L0=7.48mm、L0'=0.62mm、L1=5.53mm、L2
3=4.13mm、L4=5.33mmの時のフィルタ特性を示した
ものである。
FIG. 2 is a view similar to FIG. 1 except that the relative dielectric constant of the dielectric substrate for the strip line is 2.5, the characteristic impedance Z 0 of the main line 13 is 50 ohms, and the open-ended stubs 14, 15, 16,.
Assuming that all the characteristic impedances Zs of 17 are 90 ohms, L 0 = 7.48 mm, L 0 ′ = 0.62 mm, L 1 = 5.53 mm, L 2 =
This shows the filter characteristics when L 3 = 4.13 mm and L 4 = 5.33 mm.

【0013】(図1)に示すフィルタでは周波数が11.7
〜12.4GHzの範囲では反射損失は13dB以上であり、9.2〜
10.4GHzの周波数範囲では30dB以上の減衰量を有し、12.
7〜13.8GHzの周波数範囲では20dB以上の減衰量を有する
特性が得られている。
In the filter shown in FIG. 1, the frequency is 11.7.
In the range of ~ 12.4GHz, the return loss is more than 13dB, 9.2 ~
In the 10.4GHz frequency range, it has an attenuation of 30dB or more, and 12.
In the frequency range of 7 to 13.8 GHz, a characteristic having an attenuation of 20 dB or more is obtained.

【0014】従って、(図2)に示すような特性を有す
るフィルタは、通過帯域が11.7〜12.4GHzの周波数範囲
にあり、阻止帯域が9.2〜10.4GHzと12.7〜13.8GHzの周
波数範囲にあり、特に通過帯域の低域側で大きな減衰量
を必要とする帯域通過型のマイクロ波フィルタとして十
分に機能するものである。
Accordingly, the filter having the characteristics shown in FIG. 2 has a pass band in the frequency range of 11.7 to 12.4 GHz, a stop band in the frequency ranges of 9.2 to 10.4 GHz and 12.7-13.8 GHz, In particular, the filter sufficiently functions as a band-pass type microwave filter that requires a large amount of attenuation on the lower side of the pass band.

【0015】これは、阻止域周波数が通過域周波数の両
側に隣接して存在し、かつ、通過域周波数、阻止域周波
数ともに帯域幅が有限で、通過帯域の低域側で大きな減
衰量を必要とする場合の帯域通過型のマイクロ波フィル
タとして特に有効である。
This is because the stop band frequency exists adjacent to both sides of the pass band frequency, the pass band frequency and the stop band frequency have finite bandwidths, and a large amount of attenuation is required on the low band side of the pass band. Is particularly effective as a band-pass type microwave filter.

【0016】(図1)による実施例では主線路に並列に
終端開放スタブを接続した構成であるので通過帯域での
挿入損失を少なくできる。また、通過帯域の低域側にあ
る阻止帯域での特性については、2本の終端開放スタブ
の長さL1,L4は通過帯域よりも低域側にある阻止域周
波数の帯域内あるいは帯域近傍に減衰極がくるように阻
止域周波数の1/4波長あるいはほぼ1/4波長の長さに選
び、通過帯域の高域側にある阻止帯域での特性について
は、2本の終端開放スタブの長さL2,L3は通過帯域よ
りも高域側にある阻止域周波数の帯域内あるいは帯域近
傍に減衰極がくるように阻止域周波数の1/4波長あるい
はほぼ1/4波長の長さに選び、そして終端開放スタブの
長さL1,L2,L3,L4および間隔L0,L0'は2L0'<
2≒L3<L 1≒L4<L0<2L1の条件を満足するか、
あるいは2L0'<L2=L3<L1=L4<L0<2L1の条件
を満足するように選ぶことにより、阻止帯域から通過帯
域へ移行する領域での減衰特性が急峻で、特に通過帯域
の高域側での減衰特性が急峻で、通過帯域の低域側にあ
る阻止帯域では阻止帯域幅が比較的広帯域で減衰量が大
きいフィルタを簡単な構成により実現することができ
る。
In the embodiment according to FIG. 1, in parallel with the main line
Since the configuration is such that an open-end stub is connected,
Insertion loss can be reduced. Also, on the lower side of the pass band
For the characteristics in the stop band, two open-ended stubs
Length L1, LFourIs around the stop band lower than the pass band.
Block the attenuation pole so that it falls within or near the band of the wave number.
Select the length of 1/4 wavelength or almost 1/4 wavelength of the stopband frequency.
And the characteristics in the stopband on the higher side of the passband
Is the length L of the two open-ended stubsTwo, LThreeIs the passband
Within or near the band of the stopband frequency on the higher side
1/4 wavelength of stop band frequency or so that attenuation pole comes near
Is chosen to be approximately 1/4 wavelength long, and the open-ended stub
Length L1, LTwo, LThree, LFourAnd interval L0, L0'Is 2L0'<
LTwo≒ LThree<L 1≒ LFour<L0<2L1Satisfies the condition
Or 2L0'<LTwo= LThree<L1= LFour<L0<2L1Condition
From the stopband to the passband by choosing to satisfy
Attenuation characteristics in the transition region are sharp, especially in the pass band.
Has a steep attenuation characteristic on the high frequency side, and
The stop band is relatively wide and the attenuation is large.
Filter can be realized with a simple configuration.
You.

【0017】また(図1)の説明では終端開放スタブ1
4,15の間隔と終端開放スタブ16,17の間隔とは同一の
0であるが、必ずしも正確に同一である必要はなく、
ほぼ同一であればフィルタ特性は同一の場合と大きくず
れることはない。
In the description of FIG.
The interval as termination open stub 16, 17 of 4,15 the same L 0, but not necessarily exactly the same,
If they are almost the same, the filter characteristics do not greatly differ from the case of the same.

【0018】更に、フィルタ特性を実際に計算すればわ
かるが、終端開放スタブの間隔L0、L0'を、L0に対し
ては通過域周波数の6/16波長よりも長く、8/16波長より
も短くなるように選び、L0'に対しては通過域周波数の
2/16波長よりも短くなるように選ぶとともに、L0
0'に対しては通過域周波数の6/16波長よりも長く、9/
16波長よりも短くなるように選ぶと、特に通過帯域の高
域側にある阻止帯域で急峻な減衰特性をもち、通過帯域
の低域側にある阻止帯域では阻止帯域幅が比較的広帯域
で減衰量が大きいすぐれたフィルタが構成でき、(図
2)の特性を有するフィルタはいずれも、この条件を満
足するようなフィルタ寸法に選ばれている。
Furthermore, as will be understood from the actual calculation of the filter characteristics, the distances L 0 , L 0 ′ between the open-ended stubs are set to be longer than 6/16 wavelength of the pass band frequency for L 0 , and 8/16 Shorter than the wavelength, and for L 0
It is selected to be shorter than 2/16 wavelength, and L 0 +
For L 0 ′, longer than 6/16 wavelength of the passband frequency, 9 /
If it is selected to be shorter than 16 wavelengths, it will have a steep attenuation characteristic especially in the stop band on the higher side of the pass band, and the stop band on the lower side of the pass band will attenuate in a relatively wide band. An excellent filter having a large amount can be constructed, and all the filters having the characteristics shown in FIG. 2 are selected to have such filter dimensions that satisfy this condition.

【0019】(図3)は本発明による第2の実施例であ
る帯域通過型のマイクロ波フィルタで、入力端子31およ
び出力端子32をストリップ線路で構成される主線路33で
結び、主線路33に長さがそれぞれL1,L2,L3,L4
終端開放スタブ34,35,36,37をそれぞれ間隔L0
0',L0でもって順次並列に接続している。
FIG. 3 shows a bandpass type microwave filter according to a second embodiment of the present invention, in which an input terminal 31 and an output terminal 32 are connected by a main line 33 composed of a strip line. And open-ended stubs 34, 35, 36 and 37 having lengths L 1 , L 2 , L 3 and L 4 respectively at intervals L 0 ,
L 0 ′ and L 0 are sequentially connected in parallel.

【0020】終端開放スタブ34,37の長さL1,L4は通
過帯域よりも高域側にある阻止域周波数の帯域内あるい
は帯域近傍に減衰極がくるように阻止域周波数の1/4波
長あるいはほぼ1/4波長の長さに選ぶ。そして終端開放
スタブ35,36の長さL2,L3は通過帯域よりも低域側に
ある阻止域周波数の帯域内あるいは帯域近傍に減衰極が
くるように阻止域周波数の1/4波長あるいはほぼ1/4波長
の長さに選ぶ。
The lengths L 1 and L 4 of the open-ended stubs 34 and 37 are set to 1 of the stop band frequency so that the attenuation pole comes within or near the stop band frequency higher than the pass band. Choose a wavelength or approximately 1/4 wavelength length. The lengths L 2 and L 3 of the open-end stubs 35 and 36 are set to 1/4 wavelength of the stop band frequency so that the attenuation pole comes within or near the stop band frequency lower than the pass band. Choose about 1/4 wavelength length.

【0021】そしてL0,L0',L1,L2,L3,L4
長さは2L0<L1≒L4<L2≒L3<L0'<2L2の条件を
満足するか、あるいは2L0<L1=L4<L2=L3<L0'
<2L2の条件を満足するように選ぶと同時に、間隔L0
に対しては通過域周波数の2/16波長よりも短くなるよう
に選び、L0'に対しては通過域周波数の6/16波長よりも
長く、8/16波長よりも短くなるように選び、L0+L0'
に対しては通過域周波数の7/16波長よりも長く、10/16
波長よりも短くなるように選んでいる。
The lengths of L 0 , L 0 ′, L 1 , L 2 , L 3 , and L 4 satisfy the condition of 2L 0 <L 1 ≒ L 4 <L 2 ≒ L 3 <L 0 <L 2 . Satisfied or 2L 0 <L 1 = L 4 <L 2 = L 3 <L 0 '
<2L 2 , and at the same time, the interval L 0
For L 0 ′, select so as to be shorter than 2/16 wavelength of the pass band frequency, and for L 0 ′, select so as to be longer than 6/16 wavelength and shorter than 8/16 wavelength of the pass band frequency , L 0 + L 0
Is longer than the 7/16 wavelength of the passband frequency,
It is chosen to be shorter than the wavelength.

【0022】(図4)は(図3)において、ストリップ
線路用誘電体基板の比誘電率を2.5、主線路33の特性イ
ンピーダンスZ0を50オーム、終端開放スタブ34,35,36,
37の特性インピーダンスZsをすべて90オームとした場合
に、L0=0.89mm、L0'=8.15mm、L1=L4=3.63mm、
2=L3=4.88mmの時のフィルタ特性を示したものであ
る。
FIG. 4 is a view similar to FIG. 3 except that the relative dielectric constant of the dielectric substrate for the strip line is 2.5, the characteristic impedance Z 0 of the main line 33 is 50 ohms, and the open-end stubs 34, 35, 36,.
When the characteristic impedance Zs of all 37 is 90 ohms, L 0 = 0.89 mm, L 0 ′ = 8.15 mm, L 1 = L 4 = 3.63 mm,
This shows the filter characteristics when L 2 = L 3 = 4.88 mm.

【0023】(図4)に示すフィルタでは周波数が11.5
〜12.5GHzの範囲では反射損失は13dB以上であり、10.3
〜11.2GHzの周波数範囲では20dB以上の減衰量を有し、1
4.0〜15.6GHzの周波数範囲では30dB以上の減衰量を有す
る特性が得られている。
In the filter shown in FIG. 4, the frequency is 11.5.
In the range up to 12.5 GHz, the return loss is 13 dB or more, and 10.3 GHz.
It has an attenuation of 20 dB or more in the frequency range of
A characteristic having an attenuation of 30 dB or more is obtained in a frequency range of 4.0 to 15.6 GHz.

【0024】従って、(図4)に示すような特性を有す
るフィルタは、通過帯域が11.5〜12.5GHzの周波数範囲
にあり、阻止帯域が10.3〜11.2GHzと14.0〜15.6GHzの周
波数範囲にあり、特に通過帯域の高域側で大きな減衰量
を必要とする帯域通過型のマイクロ波フィルタとして十
分に機能するものである。これは、阻止域周波数が通過
域周波数の両側に隣接して存在し、かつ、通過域周波
数、阻止域周波数ともに帯域幅が有限で、通過帯域の高
域側で大きな減衰量を必要とする場合の帯域通過型のマ
イクロ波フィルタとして特に有効である。
Therefore, the filter having the characteristics shown in FIG. 4 has a pass band in the frequency range of 11.5-12.5 GHz, a stop band in the frequency ranges of 10.3-11.2 GHz and 14.0-15.6 GHz, In particular, the filter sufficiently functions as a band-pass type microwave filter requiring a large amount of attenuation on the high frequency side of the pass band. This is because the stopband frequency exists adjacent to both sides of the passband frequency, and both the passband frequency and the stopband frequency have a finite bandwidth, and a large amount of attenuation is required on the high side of the passband. Is particularly effective as a band-pass type microwave filter.

【0025】(図3)による実施例では主線路に並列に
終端開放スタブを接続した構成であるので通過帯域での
挿入損失を少なくできる。
In the embodiment shown in FIG. 3, an open-ended stub is connected in parallel with the main line, so that insertion loss in the pass band can be reduced.

【0026】また、通過帯域の高域側にある阻止帯域で
の特性については、2本の終端開放スタブの長さL1
4は通過帯域よりも高域側にある阻止域周波数の帯域
内あるいは帯域近傍に減衰極がくるように阻止域周波数
の1/4波長あるいはほぼ1/4波長の長さに選び、通過帯域
の低域側にある阻止帯域での特性については、2本の終
端開放スタブの長さL2,L3は通過帯域よりも低域側に
ある阻止域周波数の帯域内あるいは帯域近傍に減衰極が
くるように阻止域周波数の1/4波長あるいはほぼ1/4波長
の長さに選び、そして終端開放スタブの長さL1,L2
3,L4および間隔L0,L0'は2L0<L1≒L4<L2
3<L0'<2L2の条件を満足するか、あるいは2L0
1=L4<L2=L3<L0'<2L2の条件を満足するよう
に選ぶことにより、阻止帯域から通過帯域へ移行する領
域での減衰特性が急峻で、特に通過帯域の低域側での減
衰特性が急峻で、通過帯域の高域側にある阻止帯域では
阻止帯域幅が比較的広帯域で減衰量が大きいフィルタを
簡単な構成により実現することができる。
Regarding the characteristics in the stop band on the higher side of the pass band, the lengths L 1 and L 2 of the two open-end stubs are set.
L 4 represents select the length of 1/4 wavelength or about 1/4 wavelength of the stop band frequency as attenuation pole comes to in-band or band near the stopband frequencies in the high frequency side than the pass band, the pass band , The lengths L 2 and L 3 of the two open-end stubs are determined by the attenuation poles in or near the band of the stop band frequency lower than the pass band. And a length of 1/4 wavelength or almost 1/4 wavelength of the stop band frequency , and the lengths L 1 , L 2 ,
L 3 , L 4 and intervals L 0 , L 0 ′ are 2L 0 <L 1 {L 4 <L 2 }
Whether the condition of L 3 <L 0 ′ <2L 2 is satisfied or 2L 0 <
By selecting so as to satisfy the condition of L 1 = L 4 <L 2 = L 3 <L 0 ′ <2L 2 , the attenuation characteristic in the region where the band shifts from the stop band to the pass band is steep. A filter having a steep attenuation characteristic on the low band side and a relatively wide stop band width and a large amount of attenuation in the stop band on the high band side of the pass band can be realized with a simple configuration.

【0027】また(図3)の説明では終端開放スタブ3
4,35の間隔と終端開放スタブ36,37の間隔とは同一の
0であるが、必ずしも正確に同一である必要はなく、
ほぼ同一であればフィルタ特性は同一の場合と大きくず
れることはない。
Also, in the description of FIG.
The interval as termination open stub 36, 37 of 4,35 the same L 0, but not necessarily exactly the same,
If they are almost the same, the filter characteristics do not greatly differ from the case of the same.

【0028】更に、フィルタ特性を実際に計算すればわ
かるが、終端開放スタブの間隔L0,L0'を、L0に対し
ては通過域周波数の2/16波長よりも短くなるように選
び、L0'に対しては通過域周波数の6/16波長よりも長
く、8/16波長よりも短くなるように選ぶとともに、L0
+L0'に対しては通過域周波数の7/16波長よりも長く、
10/16波長よりも短くなるように選ぶと、特に通過帯域
の低域側にある阻止帯域で急峻な減衰特性をもち、通過
帯域の高域側にある阻止帯域では阻止帯域幅が比較的広
帯域で減衰量が大きいすぐれたフィルタが構成でき、
(図4)の特性を有するフィルタはいずれも、この条件
を満足するようなフィルタ寸法に選ばれている。
Further, as will be understood by actually calculating the filter characteristics, the intervals L 0 and L 0 ′ between the open-ended stubs are selected so that L 0 is shorter than 2/16 wavelength of the pass band frequency. , L 0 'longer than 6/16 wavelength of a pass band frequency for, together with the chosen to be shorter than 8/16 wavelength, L 0
+ L 0 'is longer than 7/16 wavelength of the passband frequency,
If it is selected to be shorter than 10/16 wavelength, the stop band on the lower side of the pass band has a steep attenuation characteristic, and the stop band on the higher side of the pass band has a relatively wide stop band. With this, an excellent filter with large attenuation can be constructed.
All filters having the characteristics shown in FIG. 4 are selected to have such filter dimensions that satisfy this condition .

【0029】[0029]

【発明の効果】本発明によれば、次のような効果があ
る。 (1)フィルタの構成要素は終端開放スタブのみで、通
過域周波数の約1波長あるいは約1/2波長の長さの主線
路上に構成されるため、フィルタ寸法が小さい。 (2)主線路に並列に終端開放スタブを接続した構成で
あるので、通過帯域での挿入損失を少なくできる。 (3)通過帯域の低域側にある阻止帯域での特性につい
ては、2本の終端開放スタブの長さL 1 ,L 4 は阻止域周
波数の帯域内あるいは帯域近傍に減衰極がくるように阻
止域周波数の1/4波長あるいはほぼ1/4波長の長さに選
び、そして通過帯域の高域側にある阻止帯域での特性に
ついては、2本の終端開放スタブの長さL 2 ,L 3 は阻止
域周波数の帯域内あるいは帯域近傍に減衰極がくるよう
に阻止域周波数の1/4波長あるいはほぼ1/4波長の長さに
選び、間隔L 0 ,L 0 'は2L 0 '<L 2 ≒L 3 <L 1 ≒L 4 <L
0 <2L 1 の条件を満足するか、あるいは2L 0 '<L 2 =L 3
<L 1 =L 4 <L 0 <2L 1 の条件を満足するように選ぶこ
とにより、阻止帯域から通過帯域へ移行する領域での減
衰特性が急峻で、阻止帯域での減衰量が大きいフィルタ
を簡単な構成により実現することができる。 (4)通過帯域の高域側にある阻止帯域での特性につい
ては、2本の終端開放スタブの長さL 1 ,L 4 は阻止域周
波数の帯域内あるいは帯域近傍に減衰極がくるように阻
止域周波数の1/4波長あるいはほぼ1/4波長の長さに選
び、そして通過帯域の低域側にある阻止帯域での特性に
ついては、2本の終端開放スタブの長さL 2 ,L 3 は阻止
域周波数の帯域内あるいは帯域近傍に減衰極がくるよう
に阻止域周波数の1/4波長あるいはほぼ1/4波長の長さに
選び、間隔L 0 ,L 0 'は2L 0 <L 1 ≒L 4 <L 2 ≒L 3
0 '<2L 2 の条件を満足するか、あるいは2L 0 <L 1
4 <L 2 =L 3 <L 0 '<2L 2 の条件を満足するように選
ぶことにより、通過帯域外での減衰特性が急峻で、阻止
帯域での減衰量が大きいフィルタを簡単な構成により実
現することができる。
According to the present invention, the following effects can be obtained.
You. (1) The only component of the filter is an open-ended stub.
A main line with a length of about 1 or about 1/2 wavelength of the over-range frequency
Since it is configured on a road, the filter size is small. (2) With a configuration in which an open-end stub is connected in parallel to the main line
As a result, insertion loss in the pass band can be reduced. (3) Regarding the characteristics in the stop band on the lower side of the pass band
In other words, the lengths L 1 and L 4 of the two open-ended stubs are around the stop band.
Block the attenuation pole so that it falls within or near the band of the wave number.
Select the length of 1/4 wavelength or almost 1/4 wavelength of the stopband frequency.
And characteristics in the stop band on the higher side of the pass band.
As a result, the lengths L 2 and L 3 of the two open-ended stubs are blocked.
The attenuation pole should be within or near the frequency band
1/4 wavelength or almost 1/4 wavelength of stopband frequency
The interval L 0 , L 0 ′ is 2L 0 ′ <L 2 ≒ L 3 <L 1 ≒ L 4 <L
0 <2L 1 or 2L 0 ′ <L 2 = L 3
<This select L 1 = L 4 <so as to satisfy the conditions of L 0 <2L 1
Reduces the region in the transition from the stopband to the passband.
Filter with steep attenuation characteristics and large attenuation in stopband
Can be realized by a simple configuration. (4) Regarding the characteristics in the stop band on the higher side of the pass band
In other words, the lengths L 1 and L 4 of the two open-ended stubs are around the stop band.
Block the attenuation pole so that it falls within or near the band of the wave number.
Select the length of 1/4 wavelength or almost 1/4 wavelength of the stopband frequency.
And characteristics in the stop band on the lower side of the pass band.
As a result, the lengths L 2 and L 3 of the two open-ended stubs are blocked.
The attenuation pole should be within or near the frequency band
1/4 wavelength or almost 1/4 wavelength of stopband frequency
The interval L 0 , L 0 ′ is 2L 0 <L 1 ≒ L 4 <L 2 ≒ L 3 <
Whether the condition of L 0 ′ <2L 2 is satisfied, or 2L 0 <L 1 =
L 4 <L 2 = L 3 <L 0 '< select so as to satisfy the condition 2L 2
The steep attenuation characteristics outside the pass band
A filter with a large amount of attenuation in the band can be implemented with a simple configuration.
Can be manifested.

【0030】[0030]

【0031】[0031]

【0032】[0032]

【0033】[0033]

【図面の簡単な説明】[Brief description of the drawings]

【図1】本発明の第1の実施例によるストリップ線路で
構成された帯域通過型のマイクロ波フィルタ回路を示す
パターン図である。
FIG. 1 is a pattern diagram showing a bandpass type microwave filter circuit constituted by a strip line according to a first embodiment of the present invention.

【図2】(図1)のマイクロ波フィルタ回路の挿入損失
の周波数特性の具体例を示す特性図である。
FIG. 2 is a characteristic diagram showing a specific example of a frequency characteristic of insertion loss of the microwave filter circuit of FIG. 1;

【図3】本発明の第2の実施例によるストリップ線路で
構成された帯域通過型のマイクロ波フィルタ回路を示す
パターン図である。
FIG. 3 is a pattern diagram showing a bandpass type microwave filter circuit constituted by a strip line according to a second embodiment of the present invention.

【図4】(図3)のマイクロ波フィルタ回路の挿入損失
の周波数特性の具体例を示す特性図である。
FIG. 4 is a characteristic diagram showing a specific example of a frequency characteristic of insertion loss of the microwave filter circuit of FIG. 3;

【図5】従来のストリップ線路で構成された帯域通過フ
ィルタのパターン図である。
FIG. 5 is a pattern diagram of a band-pass filter constituted by a conventional strip line.

【符号の説明】[Explanation of symbols]

11,31 入力端子 12,32 出力端子 13,33 主線路 14,15,16,17,34,35,36,37 終端開放スタブ 11,31 Input terminal 12,32 Output terminal 13,33 Main line 14,15,16,17,34,35,36,37 Open end stub

Claims (4)

(57)【特許請求の範囲】(57) [Claims] 【請求項1】 入力端子および出力端子を有する主線路
と、この主線路に間隔がそれぞれL0,L0',L0"(=
0 または≒L0)でもって順次並列に設けられた長さ
がそれぞれL1,L2,L3,L4の終端開放の第1,第
2,第3および第4のスタブとで構成され、かつ前記第
1および第4のスタブの長さL1,L4を通過域周波数よ
りも低域側にある第1の阻止域周波数の帯域内に減衰極
がくるように前記第1の阻止域周波数の1/4波長の長さ
に選び、前記第2および第3のスタブの長さL2,L3
通過域周波数よりも高域側にある第2の阻止域周波数の
帯域内に減衰極がくるように前記第2の阻止域周波数の
1/4波長の長さに選び、2L0'<L2≒L3<L1≒L4<L
0<2L1 または2L0'<L2=L3<L1=L4<L0<2L1
の条件を満足するように、L0,L0',L1,L2,L3
4の長さを選んだことを特徴とするマイクロ波フィル
タ。
1. A main line having an input terminal and an output terminal, and an interval between the main lines is L 0 , L 0 ′, L 0 ″ (=
L 0 or ≒ L 0 ) and the first, second, third, and fourth stubs each having an open end at L 1 , L 2 , L 3 , and L 4. And the first and fourth stubs have lengths L 1 , L 4 in the first stop band frequency band lower than the pass band frequency so that the attenuation pole comes within the first stop band frequency band. The length of the second and third stubs L 2 and L 3 is selected to be a quarter wavelength of the stop band frequency, and the length L 2 , L 3 within the band of the second stop band frequency higher than the pass band frequency. Of the second stopband frequency so that the attenuation pole comes
Select the length of 1/4 wavelength, 2L 0 ′ <L 2 ≒ L 3 <L 1 ≒ L 4 <L
0 <2L 1 or 2L 0 '<L 2 = L 3 <L 1 = L 4 <L 0 <2L 1
L 0 , L 0 ′, L 1 , L 2 , L 3 ,
Microwave filter, wherein the chosen length of L 4.
【請求項2】 主線路に設けられた第1,第2,第3お
よび第4のスタブの間隔L0,L0'およびL0"を、L0
0"に対しては通過域周波数の6/16波長よりも長く、8/
16波長よりも短くなるように選び、L0'に対しては通過
域周波数の2/16波長よりも短くなるように選ぶととも
に、L0+L0'に対しては通過域周波数の6/16波長より
も長く、9/16波長よりも短くなるように選んだことを特
徴とする請求項1記載のマイクロ波フィルタ。
2. The distances L 0 , L 0 ′ and L 0 ″ between first, second, third and fourth stubs provided on a main line are represented by L 0 ,
L 0 "is longer than 6/16 wavelength of the passband frequency,
16 so as to select a shorter wavelength than, L 0 'with chosen to be shorter than 2/16 wavelength of a pass band frequency for, L 0 + L 0' of the passband frequency for 6/16 2. The microwave filter according to claim 1, wherein the microwave filter is selected to be longer than the wavelength and shorter than 9/16 wavelength.
【請求項3】 入力端子および出力端子を有する主線路
と、この主線路に間隔がそれぞれL0,L0',L0"(=
0または≒L0)でもって順次並列に設けられた長さが
それぞれL1,L2,L3,L4の終端開放の第1,第2,
第3および第4のスタブとで構成され、かつ前記第1お
よび第4のスタブの長さL1,L4を通過域周波数よりも
高域側にある第1の阻止域周波数の帯域内に減衰極がく
るように前記第1の阻止域周波数の1/4波長の長さに選
び、前記第2および第3のスタブの長さL2,L3を通過
域周波数よりも低域側にある第2の阻止域周波数の帯域
内に減衰極がくるように前記第2の阻止域周波数の1/4
波長の長さに選び、2L0<L1≒L4<L2≒L3<L0'<
2L2 または2L0<L1=L4<L2=L3<L0'<2L2の条
件を満足するように、L0,L0',L1,L2,L3,L4
の長さを選んだことを特徴とするマイクロ波フィルタ。
3. A main line having an input terminal and an output terminal, and intervals between the main lines are L 0 , L 0 ′, L 0 ″ (=
L 0 or ≒ L 0 ), the first , second , and second lengths of the open ends are L 1 , L 2 , L 3 , and L 4 , respectively.
The first and fourth stubs have lengths L 1 and L 4 within a band of a first stop band frequency higher than a pass band frequency. The length of the first and second stubs is selected to be a quarter wavelength of the first stop band frequency so that the attenuation pole comes, and the lengths L 2 and L 3 of the second and third stubs are set to be lower than the pass band frequency. One-fourth of the second stop band frequency so that the attenuation pole falls within the band of a certain second stop band frequency.
Select the length of the wavelength, 2L 0 <L 1 ≒ L 4 <L 2 ≒ L 3 <L 0 '<
2L 2 or 2L 0 <L 1 = L 4 <L 2 = L 3 <L 0 '< so as to satisfy the condition 2L 2, L 0, L 0 ', L 1, L 2, L 3, L 4
Microwave filter characterized by choosing the length of.
【請求項4】 主線路に設けられた第1,第2,第3お
よび第4のスタブの間隔L0,L0'およびL0"を、L0
0"に対しては通過域周波数の2/16波長よりも短くなる
ように選び、L0'に対しては通過域周波数の6/16波長よ
りも長く、8/16波長よりも短くなるように選ぶととも
に、L0+L0'に対しては通過域周波数の7/16波長より
も長く、10/16波長よりも短くなるように選んだことを
特徴とする請求項3記載のマイクロ波フィルタ。
4. The distances L 0 , L 0 ′ and L 0 ″ between the first, second, third and fourth stubs provided on the main line are represented by L 0 ,
L 0 "chosen to be shorter than 2/16 wavelength of a pass band frequency for, L 0 'longer than 6/16 wavelength of a pass band frequency for shorter than 8/16 Wavelength 4. The microwave according to claim 3 , wherein L 0 + L 0 ′ is selected so as to be longer than 7/16 wavelength of the pass band frequency and shorter than 10/16 wavelength. filter.
JP3180868A 1991-07-22 1991-07-22 Microwave filter Expired - Fee Related JP2800478B2 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP3180868A JP2800478B2 (en) 1991-07-22 1991-07-22 Microwave filter
US07/916,252 US5291161A (en) 1991-07-22 1992-07-21 Microwave band-pass filter having frequency characteristic of insertion loss steeply increasing on one outside of pass-band

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP3180868A JP2800478B2 (en) 1991-07-22 1991-07-22 Microwave filter

Publications (2)

Publication Number Publication Date
JPH0529803A JPH0529803A (en) 1993-02-05
JP2800478B2 true JP2800478B2 (en) 1998-09-21

Family

ID=16090758

Family Applications (1)

Application Number Title Priority Date Filing Date
JP3180868A Expired - Fee Related JP2800478B2 (en) 1991-07-22 1991-07-22 Microwave filter

Country Status (1)

Country Link
JP (1) JP2800478B2 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000151207A (en) 1998-11-12 2000-05-30 Mitsubishi Electric Corp Low pass filter

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6444601A (en) * 1987-08-12 1989-02-17 Sharp Kk Band-stop filter
JPH0728162B2 (en) * 1988-11-11 1995-03-29 松下電器産業株式会社 Microwave filter
JPH0728163B2 (en) * 1988-11-11 1995-03-29 松下電器産業株式会社 Microwave filter

Also Published As

Publication number Publication date
JPH0529803A (en) 1993-02-05

Similar Documents

Publication Publication Date Title
EP0537798B1 (en) Microwave filter
EP0084854B1 (en) Resonator type bandpass filter
US5291161A (en) Microwave band-pass filter having frequency characteristic of insertion loss steeply increasing on one outside of pass-band
US4288766A (en) Microwave circuit
US4450584A (en) Microwave integrated circuit mixer
US6252476B1 (en) Microstrip resonators and coupled line bandpass filters using same
JPS6310601B2 (en)
JP2800478B2 (en) Microwave filter
JPH06101643B2 (en) Bandpass filter
JP2800479B2 (en) Microwave filter
JP2671571B2 (en) Microwave filter
CN115275545A (en) Compact absorption type filtering power divider
CN111384535B (en) Double-passband power division filter
JPH0728163B2 (en) Microwave filter
CN109244610B (en) Adjustable dual-mode filter
CN220086341U (en) Ceramic filter
KR19980067593A (en) Microwave Lowpass Filters
JPH0728162B2 (en) Microwave filter
CN205194819U (en) Stripline band pass filter with high out -band inhibition performance
CN221080313U (en) Miniaturized microstrip parallel coupling band-pass filter based on lumped distribution
CN216488445U (en) Narrow-band-pass filter
JP4501729B2 (en) High frequency filter
CN221009212U (en) Wide stop band microstrip band-pass filter
JPS6359606B2 (en)
CN116666925A (en) Miniaturized broadband planar three-way band-pass filter

Legal Events

Date Code Title Description
LAPS Cancellation because of no payment of annual fees