CN104078727B - Tandem type one side elliptic function line filter - Google Patents
Tandem type one side elliptic function line filter Download PDFInfo
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- CN104078727B CN104078727B CN201410245635.8A CN201410245635A CN104078727B CN 104078727 B CN104078727 B CN 104078727B CN 201410245635 A CN201410245635 A CN 201410245635A CN 104078727 B CN104078727 B CN 104078727B
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Abstract
A kind of tandem type one side elliptic function line filter circuit that the present invention proposes, distributed parameter network is constituted by transmission line element such as input and output transmission line, series connection cruciform joint, short-circuited transmission line minor matters, cascaded transmission line joint and series transmission lines joints, first series connection cruciform joint (2) is connected with second cruciform joint (7) arranged opposite, being connected by cascaded transmission joint (3) between the two relative port, the two two are connected by series transmission lines joint (4) with side ports；First series connection cruciform joint (2) another two port connects input transmission line (1) and the first short-circuited transmission line minor matters (5) respectively, and the another two port of the second series connection cruciform joint (7) connects output transmission line (8) and the second short-circuited transmission line minor matters (6) respectively.In appropriate design wave filter, each transmission line element parameter realizes unilateral elliptic function transmission characteristic.The present invention is suitable for microwave and millimeter wave frequency band low middling bandwidth, low-loss, highly selective filter.
Description
Technical field
The present invention relates to one be widely used in the systems such as microwave and millimeter wave band communication, radar and measuring instrument, use
Carry out the frequency response of control signal, block the transmission of garbage signal frequency component, make useful signal frequency component almost without decay
The wave filter that ground passes through.
Background technology
Wave filter is microwave circuit and wide variety of passive circuit in system, is used for realizing specific selecting frequency characteristic, filter
Ripple device can be divided into high pass, low pass, band logical by transmission characteristic and the type such as band resistance, and the pass band insertion loss of wave filter, stopband suppress
The performance indications of circuit are had a great impact by the performances such as degree.Along with frequency resource growing tension, frequency spectrum the most crowded, wireless
The selecting frequency characteristic of wave filter is had higher requirement by electricity system, it is desirable to have more precipitous intermediate zone attenuation characteristic (or high
Squareness factor), passband low insertion loss, smooth passband group delay, the characteristic such as bigger bandwidth of rejection and belt resistance inhibitor system, and
And the raising required along with system compact, need to realize as far as possible the miniaturization of wave filter and integrated.
For the ease of utilizing network synthesis technology to design wave filter, traditional method is to utilize specific function approximation institute
The filter transfer characteristic needed, and realize specific transfer function by network synthesis.It is commonly used to approach filter transfer characteristic
Type function has maximally-flat type, Chebyshev type and Elliptic Function Type, and wherein Elliptic Function Type transfer function is at wave filter
There is at stopband finite frequency transmission zero and limit, and therefore improve the Out-of-band rejection performance of band filter.Elliptic function
Filter construction is compact, has more preferable transient characteristic and higher Out-of-band rejection degree than Chebyshev filter, can realize superior
Frequency-selecting performance.But circuit realiration is complicated, it is typically employed between non-conterminous resonator cavity the cross-coupled manner that induces one and realizes.Though
So have been extensively studied with the comprehensive of cross-linked wave filter and design this, but its processing and debugging difficulty are the most relatively
Greatly, its engineer applied is limited.
In order to realize the good frequency selective characteristic near working band, currently mainly use band filter and band resistance filter
Ripple device, but there is the band filter of abrupt transition band attenuation characteristic it is generally required to multiple filter, multiple filter be by
A series of resonators intercoupled are constituted, and its insertion loss is relatively big, and in band, group delay and fluctuation thereof increase, and volume is relatively simultaneously
Greatly.Multistage band elimination filter has same shortcoming.The wave filter using single high q-factor resonant tank can realize relatively being inserted into damage
Consumption, but this single-mesh filter narrower bandwidth, be difficult to meet application request.
Wave filter much should in, the selecting frequency characteristic near system working frequency range more paid close attention to, and wave filter undershoot
Entering loss and small form factor requirements is even more important, typical application includes as preselector, duplexer or multiplexer, sends out for suppression
Penetrate the wave filter of the specific clutter component of signal and for launching the wave filter of leakage in receiving front-end suppression.As a rule,
These wave filter only require have precipitous intermediate zone characteristic, moderate passband and resistance band, but requirement in the one side of passband
Insertion Loss is the lowest, to reduce system loss, should have simple in construction and miniaturization feature, it is simple to processing realizes and system simultaneously
Integrated application.
Summary of the invention
It is an object of the invention to weak point and the application demand existed for above-mentioned prior art, it is provided that a kind of circuit shape
Formula is simple, it is easy to integrated, miniaturization, and passband and bandwidth of rejection are moderate, it is easy to accomplish low insertion loss in passband, has excellent
The unilateral elliptic function transmission characteristic line filter of frequency selectivity.
For reaching object above, the present invention proposes a kind of tandem type one side elliptic function line filter, including input
The transmission line elements such as output transmission line, series connection cruciform joint, short-circuited transmission line minor matters, cascaded transmission line joint and series transmission lines joint
Part, it is characterised in that: described transmission line element all uses the various high frequency transmission line forms including parallel wire, described string
Connection cruciform joint is a kind of four port transmission kind of thread elements, and its function is connected in series with type transmission line for realizing any four；Filter
In ripple device circuit, input and output transmission line, series connection cruciform joint, short-circuited transmission line minor matters, cascaded transmission line joint and series-connected transmission
Line joint transmission line element constitutes distributed parameter network, and wherein, the first series connection cruciform joint 2 is relative with the second series connection cruciform joint 7
Arrangement, by cascaded transmission joint 3 connection between the two relative port, the two two are saved by series transmission lines with side ports
4 connect；First series connection cruciform joint 2 another two port connects input transmission line 1 and the first short-circuited transmission line minor matters 5 respectively, the
The another two port of two series connection cruciform joints 7 connects output transmission line 8 and the second short-circuited transmission line minor matters 6 respectively.Have above-mentioned
The distributed constant two-port network of annexation has multiple resonance characteristic, appropriately designed transmission line element parameter, and this network exists
One group of non-zero finite frequency transmission zero and one group of non-zero finite frequency hop zero point will be produced in wave filter working band, the two
Do not overlap adjoining on the frequency axis, thus there is unilateral elliptic function filter characteristic.
The present invention has the advantages that compared to prior art
Filter circuit form is simple, operating frequency up to millimeter wave frequency band more than, it is easy to accomplish integrated.The present invention carries
The wave filter gone out pertains only to basic transmission line element, has excellent high frequency performance, and filter circuit can accurate modeling and imitative
Very, it is easy to design and realize.The transmission line form of transmission line element used is not limited；Series connection cruciform joint can use
The various variant such as two series connection T connector cascades；In wave filter, short-circuited transmission line minor matters can use electrical length to increase and decrease 90 °
Open circuited transmission line minor matters form；Transmission line element to use straight line, broken line, crepe cord or a combination thereof form, and can be adopted
With multilayer dielectricity substrate integrated transmission-line and by forms such as interlayer interconnections, wave filter volume size can be reduced.Meanwhile, filtering
Device circuit is only with transmission line element, and transmission line element has that parasitic parameter is little, low-loss and the feature of excellent in high-frequency characteristics, makes
Obtain circuit and can apply to realize the low loss filter of more than millimeter wave frequency band.Therefore, wave filter operating frequency is up to millimeter wave
With super band.Wave filter can use planar transmission line form, it is easy to processing and fabricating and to realize wave filter integrated.
Wave filter has low insertion loss in unilateral elliptic function filter characteristic, moderate bandwidth and passband.And the present invention
The symmetrical Two-port netwerk distributed parameter network with multiple resonance characteristic, its transmission coefficient cut-off frequency is constituted by transmission line element
fcResonant frequency f in short-circuited transmission line minor mattersrNear.By selecting impedance and the electrical length parameter of each transmission line element, can produce
Raw two or more frequency is below or higher than fcNon-zero finite frequency hop zero point, and in its vicinity frequency band shaping filter lead to
Band；Produce two or more frequency to be above or less than f simultaneouslycNon-zero finite frequency transmission zero, and frequency band shape in its vicinity
Become filter stop bend, thus realize fcNeighbouring unilateral elliptic function low pass or high-pass filtering characteristic.Due to passband and stopband respectively
There is two or more reflection zero and transmission zero, thus there is passband and the bandwidth of rejection of 10%～20%.Simultaneously as this
The filter circuit of invention does not has the coupled structure of complexity, and it is special that the simple transmission kind of thread elements used itself has again low-loss
Property, it is thus susceptible to realize low insertion loss in passband.
Wave filter is easily achieved miniaturization.Its physical arrangement closely, circuit area less than have same selectivity and
The 1/4 of the interdigital filter of same transmission line form, also compact than other elliptic function filter.
This wave filter has excellent selectivity, and attenuation pole and the transmission pole of passband in stopband can be controlled respectively
System, can realize the most precipitous selecting frequency characteristic curve near cut-off frequency.This wave filter has moderate the leading to of 10-20%
Band and bandwidth of rejection, in-band insertion loss is little, is suitable for microwave and millimeter wave frequency band low middling bandwidth, low-loss, high selection
Property wave filter.
The good agreement of test result and simulation result demonstrates correctness and the effectiveness of this filter circuit.Test
Show: this wave filter can meet the requirement of miniaturization, there is again abrupt transition band attenuation characteristic and moderate passband and resistance
Band bandwidth, has the excellent filtering characteristics such as pass band insertion loss is low simultaneously.Based on above reason, this wave filter is particularly suitable for should
For miniaturization, integrated duplexer, preselector and the transmitting signal near-end contour selectivity of spurious reduction wave filter, low-loss filter
Ripple device.
Accompanying drawing explanation
Fig. 1 is tandem type one side of the present invention elliptic function line filter circuit diagram.
Fig. 2 is reflection and the transmission spy of the tandem type one side elliptic function line filter using rectangular waveguide transmission line
Linearity curve schematic diagram.
In figure: 1 input transmission line, 2 first series connection cruciform joints, 3 cascaded transmission line joints, 4 series transmission lines joints, 5 first
Short-circuited transmission line minor matters, 6 second short-circuited transmission line minor matters, 7 second series connection cruciform joints, 8 output transmission lines.
Detailed description of the invention
Refering to Fig. 1.In embodiment described below, tandem type one side elliptic function line filter is by input and output
6 basic transmission line elements such as transmission line, series connection cruciform joint, short-circuited transmission line minor matters, cascaded transmission line joint, series transmission lines joint
Part is constituted, and in Fig. 1, each transmission line all have employed two-wire form and represents, physical circuit realizes using comprising two conductor transmission line
In interior various high frequency transmission line forms, described transmission line element all uses the various high frequency transmission lines including parallel wire
Form, described series connection cruciform joint is a kind of four port transmission kind of thread elements, its function for realize any four with type transmission line
It is connected in series；In filter circuit, input and output transmission line, series connection cruciform joint, short-circuited transmission line minor matters, cascaded transmission line joint
Constituting distributed parameter network with series transmission lines joint transmission line element, wherein, the first series connection cruciform joint 2 is connected with second cross
Joint 7 arranged opposite, by cascaded transmission joint 3 connection between the two relative port, the two two pass through string with side ports
Connection transmission line joint 4 connection；First series connection cruciform joint 2 another two port connects input transmission line 1 and the first short circuit transmission respectively
Line minor matters 5, the another two port of the second series connection cruciform joint 7 connects output transmission line 8 and the second short-circuited transmission line minor matters respectively
6。
In circuit shown in Fig. 1, input signal is connected cruciform joint 2 from input transmission line 1 feed-in first, owing to impedance is lost
Joining, part is reflected back toward input transmission line herein, and residual signal is divided into two-way transmission, and a road is concatenated transmission line joint 4, another
Road saves 3 via cascaded transmission line, and two paths of signals synthesizes at the second series connection cruciform joint 7, and has part signal because of mismatch more simultaneously
Secondary being reflected, residue composite signal exports from output transmission line 8.First short-circuited transmission line minor matters the 5, second short-circuited transmission line minor matters
6 are used for adjusting input and output side reflected signal amplitude and phase place.
Initial parameter is optional as follows: at given filter cutoff frequency fcOn, cascaded transmission line joint 3 has and is less than
The electrical length of 180 °, series transmission lines joint 4 has more than 270 ° but is less than the electrical length of 360 °, the first short-circuited transmission line minor matters 5
Identical with the second short-circuited transmission line minor matters 6, and electrical length is all higher than 180 ° but less than 360 °.By selecting biography in range above
Defeated kind of thread elements electrical length, and design suitable transmission line element characteristic impedance, wave filter can realize fcNeighbouring is unilateral oval
Function transfer characteristic.
In filter circuit, the first short-circuited transmission line minor matters 5, the second short-circuited transmission line minor matters 6 parameter is identical, in transmission
Zero frequency fs1Upper electrical length all reaches 270 °, is equivalent to series connection open circuit, forms a transmission zero.Input signal passes from input
Defeated line 1 feed-in first is connected cruciform joint 2, and part signal is reflected herein, and remaining signal is divided into two-way transmission, and a road is through string
Connection transmission line joint 4, another road saves 3 via cascaded transmission line, in frequency transmission zero fs2On, the transmission coefficient width of this two paths
Spending equal, opposite in phase, the two paths of signals after transmission is cancelled out each other at the second series connection cruciform joint 7, produces second transmission
Zero point.
Frequency input signal is less than transmission zero fs1Time, the first short-circuited transmission line minor matters 5 and the second short-circuited transmission line minor matters 6
Electrical length, between 180 °～270 °, is equivalent to inductance series reactor, and cascaded transmission line joint 3 and series transmission lines joint 4 combines
After be equivalent to shunt capacitance, this four elements combination forms T-shaped low-pass networks, can be equivalent to a right-handed transmission line joint.Suitably
Select linear electrical parameter, less than transmission zero fs1At least two nonzero frequency fp1、fp2On make this right-handed transmission line save impedance
Mate with input transmission line 1 and output transmission line 8, form two reflection zeros, and make fp1<fp2<fs2<fs1, at fp1、fp2Attached
Nearly frequency band shaping filter passband, at fs1、fs1Neighbouring frequency band shaping filter stopband, passband and stopband are close to fs1Cut
Only frequency fcUpper adjacent, so that wave filter has fcNeighbouring unilateral elliptic function passes the defeated characteristic of low pass.
Frequency input signal is higher than transmission zero fs1Time, the first short-circuited transmission line minor matters 5 and the second short-circuited transmission line minor matters 6
Electrical length, between 270 °～360 °, is equivalent to capacitive series reactance, and cascaded transmission line joint 3 and series transmission lines joint 4 combines
After be equivalent to shunt inductance, this four elements combination forms T-shaped high pass networks, can be equivalent to a left hand transmission line joint, suitably
Select linear electrical parameter, higher than transmission zero fs1At least two finite frequency fp3、fp4On make this left hand transmission line save impedance
With input transmission line 1 and output transmission line 8 impedance matching, form two finite frequency reflection zeros, and make fs1<fs2<fp3<
fp4.At fp1、fp2Neighbouring frequency band shaping filter passband, at fs1、fs1Neighbouring frequency band shaping filter stopband, passband and stopband
Close to fs1Cut-off frequency fcUpper adjacent, so that wave filter has fcNeighbouring unilateral elliptic function high pass transmission characteristic..
Transmission line element transmission line form used is not limited by circuit design；First series connection cruciform joint 2, the second string
Connection cruciform joint 7 can use the various variant such as two series connection T connector cascades；Transmission line element can use straight line,
Broken line, crepe cord or a combination thereof form, and use multilayer dielectricity substrate integrated transmission-line and by forms such as interlayer interconnections,
To reduce wave filter volume size.
Fig. 2 describes the anti-of a typical metal rectangular waveguide tandem type one side elliptic function line filter circuit
Penetrate and transmission characteristic, it can be clearly seen that there are 3 transmission zeros in stopband from figure, in passband, have three reflection zeros.
The present invention is embodied as using following steps:
First according to system application requirement, suitable transmission line way of realization is selected.Consider the integrated optional of wave filter
Select the plane class transmission line such as coplanar striplines, the line of rabbet joint, consider that low-loss then should select the low loss lines such as waveguide, but need to examine
Consider and use same transmission line form with prime or late-class circuit, increase with the volume size avoiding transport mode translations to bring and
Thus introduce extra loss.Secondly, according to application demand, cut-off frequency f is determinedc, passband and bandwidth of rejection, passband and stopband
Bandwidth fcBeing normalized to relative bandwidth, its value should be less than 20%.
Utilize CAD program of microwave circuit, set up respective filter circuit, the transmission characteristic needed for setting
Design object, by the Optimized Program of software, determines each element transmission line parameter.Can also be calculated by manual iteration
Becoming wave filter design, method is as follows: set two transmission zeros f in filter stop bends1、fs2, two reflection zeros in passband
It is f for left side elliptic function filterp1、fp2, it is f to right side elliptic function filterp3、fp4.By wave filter operation principle institute
The formation transmission zero stated and the condition of reflection zero set up equation group, solve and obtain the impedance of each transmission line element and electricity is long
Degree.
After determining design parameter, electromagnetic simulation software environment is set up the structural model of wave filter, imitated by electromagnetic field
Really carry out final design checking.
Claims (9)
1. a tandem type one side elliptic function line filter, including following transmission line element: input, export transmission line,
Series connection cruciform joint, short-circuited transmission line minor matters, cascaded transmission line joint and series transmission lines joint, it is characterised in that: described transmission line
Element all uses the high frequency transmission line form including parallel wire, described series connection cruciform joint to be a kind of four port transmission lines
Element, its function is connected in series with type transmission line for realizing any four；In filter circuit, input transmission line passes with output
Defeated line, series connection cruciform joint, short-circuited transmission line minor matters, cascaded transmission line joint and series transmission lines joint transmission line element constitute distribution
Parameter two-port network, wherein, the first series connection cruciform joint (2) is connected with second cruciform joint (7) arranged opposite, and the two is relative
Port between by cascaded transmission joint (3) connect, the two two with side ports by series transmission lines joint (4) connect；The
One series connection cruciform joint (2) another two port connects input transmission line (1) and the first short-circuited transmission line minor matters (5) respectively, and second
The another two port of series connection cruciform joint (7) connects output transmission line (8) and the second short-circuited transmission line minor matters (6) respectively, and first
Short-circuited transmission line minor matters (5), the second short-circuited transmission line minor matters (6) are in frequency fs1Upper electrical length reaches 270, is equivalent to shorted to earth,
Form transmission zero fs1；The distributed constant two-port network with above-mentioned annexation has multiple resonance characteristic, this net
Network will produce one group of non-zero finite frequency transmission zero and one group of non-zero finite frequency hop zero point in wave filter working band,
The two does not overlaps adjoining on the frequency axis, thus has unilateral elliptic function filter characteristic.
Tandem type one side the most according to claim 1 elliptic function line filter, it is characterised in that: in given filter
Ripple device cut-off frequency fcOn, cascaded transmission line joint (3) has less than 180oElectrical length, series transmission lines joint (4) has and is more than
270oBut less than 360oElectrical length, the first short-circuited transmission line minor matters (5) are identical with the second short-circuited transmission line minor matters (6), and electricity is long
Degree is all higher than 180oBut less than 360o 。
Tandem type one side the most according to claim 1 elliptic function line filter, it is characterised in that: input signal exists
After first series connection cruciform joint (2) place part is reflected, remaining signal is divided into two-way, respectively via cascaded transmission line joint (3) and
Series transmission lines joint (4) two paths transmission, in frequency fs2On, the transmission coefficient amplitude of this two paths is equal, opposite in phase,
Two paths of signals after transmission is cancelled out each other at the second series connection cruciform joint (7) place, produces second transmission zero fs2。
Tandem type one side the most according to claim 3 elliptic function line filter, it is characterised in that: frequency is less than passing
Defeated zero point fs1Time, the first short-circuited transmission line minor matters (5) and the second short-circuited transmission line minor matters (6) electrical length 180～270 it
Between, it is equivalent to inductance series reactor, and is equivalent to shunt capacitance after cascaded transmission line joint (3) and series transmission lines joint (4) combination,
These four element combinations form T-shaped low-pass network, can be equivalent to a right-handed transmission line joint.
Tandem type one side the most according to claim 4 elliptic function line filter, it is characterised in that: suitably select to pass
Defeated line parameter, less than transmission zero fs1Two nonzero frequency fp1、fp2On make this right-handed transmission line joint impedance with input transmission
Line (1) and output transmission line (8) coupling, form two reflection zeros, and make fp1<fp2<fs2<fs1, at fp1、fp2Neighbouring frequency band
Shaping filter passband, simultaneously at fs1、fs1Neighbouring frequency band shaping filter stopband, passband and stopband are close to fs1Cut-off
Frequency fcUpper adjacent, so that wave filter has fcNeighbouring right side elliptic function transmission characteristic.
Tandem type one side the most according to claim 1 elliptic function line filter, it is characterised in that: input signal frequency
Rate is higher than transmission zero fs1Time, the first short-circuited transmission line minor matters (5) and the second short-circuited transmission line minor matters (6) electrical length 270～
Between 360, it is equivalent to capacitive series reactance, and is equivalent to also after cascaded transmission line joint (3) and series transmission lines joint (4) combination
Connection inductance, these four element combinations form T-shaped high pass network, are equivalent to a left hand transmission line joint.
Tandem type one side the most according to claim 6 elliptic function line filter, it is characterised in that: suitably select to pass
Defeated line parameter, can be higher than transmission zero fs1Two reflection zero frequencies fp3、fp4On make this left hand transmission line joint impedance with defeated
Enter transmission line (1) and output transmission line (8) impedance matching, form two finite frequency reflection zeros, and make fs1<fs2<fp3<
fp4At fp1、fp2Neighbouring frequency band shaping filter passband, simultaneously at fs1、fs1Neighbouring frequency band shaping filter stopband, passband and
Stopband is close to fs1Cut-off frequency fcUpper adjacent, so that wave filter has fcNeighbouring left side elliptic function transmission spy
Property.
Tandem type one side the most according to claim 1 elliptic function line filter, it is characterised in that: have two in stopband
Individual or above non-zero finite transmission zero, has two or more non-zero finite reflection zeros in passband.
Tandem type one side the most according to claim 1 elliptic function line filter, it is characterised in that: set wave filter
Two transmission zeros f in stopbands1、fs2, two reflection zeros in passband are f for left side elliptic function filterp1、fp2, right
Right side elliptic function filter is fp3、fp4。
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| CN201410245635.8A CN104078727B (en) | 2014-06-04 | 2014-06-04 | Tandem type one side elliptic function line filter |
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| JP6790907B2 (en) * | 2017-02-23 | 2020-11-25 | 株式会社村田製作所 | Multiplexer, transmitter and receiver |
| CN110890869A (en) * | 2019-12-16 | 2020-03-17 | 华南理工大学 | High-efficiency broadband power amplifier and radio frequency transceiver |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4779064A (en) * | 1987-04-01 | 1988-10-18 | Raytheon Company | Radio frequency coaxial cable |
| CN102318133A (en) * | 2009-04-30 | 2012-01-11 | 凯瑟雷恩工厂两合公司 | Filter arrangement |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001230610A (en) * | 2000-02-15 | 2001-08-24 | Ngk Insulators Ltd | Laminated dielectric resonator |
| US7187252B2 (en) * | 2004-11-30 | 2007-03-06 | Motorola, Inc. | Apparatus for delaying radio frequency signals |
-
2014
- 2014-06-04 CN CN201410245635.8A patent/CN104078727B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4779064A (en) * | 1987-04-01 | 1988-10-18 | Raytheon Company | Radio frequency coaxial cable |
| CN102318133A (en) * | 2009-04-30 | 2012-01-11 | 凯瑟雷恩工厂两合公司 | Filter arrangement |
Non-Patent Citations (1)
| Title |
|---|
| 同轴线滤波器;游德清;《电子学报》;19621031;第1卷(第2期);全文 * |
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