CN109921761A - It is a kind of to reconcile the reconfigurable filter of switchable function with passband - Google Patents
It is a kind of to reconcile the reconfigurable filter of switchable function with passband Download PDFInfo
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- CN109921761A CN109921761A CN201910204009.7A CN201910204009A CN109921761A CN 109921761 A CN109921761 A CN 109921761A CN 201910204009 A CN201910204009 A CN 201910204009A CN 109921761 A CN109921761 A CN 109921761A
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
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Abstract
The reconfigurable filter of switchable function can be reconciled with passband the invention proposes a kind of, specifically include that two couplings be loaded with the switching circuit and variable capacitance realized by PIN diode quarter-wave (λ/ 4) resonator, incoming feeder and output feeder；One end of resonator is grounded, another to terminate the switching circuit realized by PIN diode, realization pairλThe control of/4 resonator basic modes；The variable capacitance loaded in resonator specific position is used forλThe tuning of/4 resonator basic modes；It is connected between incoming feeder end and output feeder end and corresponding resonator by another variable capacitance.The filter has used Novel resonator loading scheme, and variable capacitance and the switching circuit realized by PIN diode are loaded into a resonator simultaneously.Reconfigurable filter based on this conceptual design realizes the switchable of passband by the switching circuit of control resonator one end at any time during band connection frequency tuning.
Description
Technical field
It is the present invention relates to wireless communication technology field, in particular to a kind of to reconcile the weighing of switchable function with passband
Structure filter.
Background technique
Wireless communication system requires the component with reconfigurable property higher and higher, it would be desirable to empty in limited circuit
Between or cost in realize more functions.So various restructural components, such as power divider, coupler, duplexer, antenna
With all studied application requirement to meet radio-frequency front-end of filter.And bandpass filter) because its have can transmit signal simultaneously
The characteristics of inhibiting unnecessary interference plays key effect in a communications system.Therefore, in recent years scholar to various reconfigurabilities
Bandpass filter is furtherd investigate.Wherein, semiconductor diode (varactor or PIN diode) is loaded into micro-strip filter
It is most simple and generally the least expensive one of the method for realizing Reconfigurability in wave device.In addition, restructural bandpass filter is in science
Research with industrial circle is concentrated mainly on two aspects: the adjustability in the switchable property and frequency spectrum of passband.With radio frequency system
The development united to more high integration, it is in demand for having more multi-functional equipment.However, up to the present, for microwave
The passband while frequency-tunable of reconfigurable filter and switchable good solution not yet.
Summary of the invention
It is an object of the invention to: overcome the defect of the above-mentioned prior art, it is switchable to propose that there is one kind passband can reconcile
The reconfigurable filter of function.
In order to achieve the above object, reconfigurable filter proposed by the present invention, comprising: two coupling be loaded with by PIN
The switching circuit and variable capacitance that diode is realizedλ/ 4 resonators, incoming feeder and output feeder；It is describedλ/ 4 resonators
One end ground connection is another to terminate the switching circuit realized by PIN diode, realization pairλThe control of/4 resonator basic modes；Load is humorous
The variable capacitance of vibration device specific positionC v1ForλThe tuning of/4 resonator basic modes；The end of the incoming feeder and output feeder
End with it is correspondingλPass through variable capacitance between/4 resonatorsC v2It is connected.
Invention also with the further feature that
1, the reconfigurable filter has used Novel resonator loading scheme, i.e., realizes by variable capacitance and by PIN diode
Switching circuit simultaneously be loaded into a resonator, the variable capacitanceC v1Load existsλ/ 4 resonator specific positions, by PIN
The switching circuit load that diode is realized existsλ/ 4 resonator one end.
2, when load existsλWhen the switching circuit of/4 resonator one end disconnects, obtain tunableλ/ 4 resonators, filter
Band connection frequency it is tunable, load resonator specific position variable capacitanceC v1For adjusting the fundamental frequency of filter, even
Connect the variable capacitance of feeder line resonatorC v2For adjusting external sort factor to meet constant absolute bandwidth requirement.
3, when load existsλWhen the switching circuit conducting of/4 resonator one end, resonator both ends, which are all grounded, (to be becomeλ/ 2 resonance
Device), resonance frequency shifts, and filter is closed in designed frequency range, and when load is in resonator specific position
Variable capacitanceC v1When constant, by the variable capacitance for adjusting connection feeder line resonatorC v2Can Optimal Filter band it is interior every
From.
4, the incoming feeder and output feeder are provided with the minor matters for intercoupling.
5, described with stacked metal floor and medium substrateλ/ 4 resonators, incoming feeder, output feeder and correspondence
Minor matters and two switching circuits realized by PIN diode and four variable capacitances be all set in the upper table of medium substrate
Face, the variable capacitanceC v1Ground terminal by perforation medium substrate metal throuth hole and metal floor be in electrical contact；It is described by PIN
In the switching circuit that diode is realized, metal throuth hole and metal floor electricity that the cathode of PIN diode passes through perforation medium substrate
Contact.
In order to which the adjustability of passband and switchable property to be integrated into single filter, the invention proposes Novel resonators
Loading scheme, it may be assumed that by variable capacitanceC v1It is loaded into the switching circuit realized by PIN diode in a resonator, it can power transformation
HoldC v1Load existsλ/ 4 resonator specific positions, the switching circuit load realized by PIN diode existλ/ 4 resonator one end.When opening
When powered-down road disconnects, tunable resonator, the frequency-tunable of mode of resonance can get；It is humorous when switching circuit conducting
Shaking, device both ends are all short-circuit, and resonance frequency shifts, and therefore, will inhibit in interested frequency range interior resonance.
The present invention utilizes restructuralλ/ 4 uniform impedance resonators, have devised that a kind of that there is passband can reconcile is switchable
The reconfigurable filter of function.Frequency tuning passband by load uniform impedance resonator specific position variable capacitance realization,
Load the conducting (ON) that the switching circuit realized by PIN diode in uniform impedance resonator one end controls each frequency passband
Or close (OFF) state.In addition, being increased in feed structure between two additional variable capacitances and source and load
Coupled structure.When filter work is in ON state, it can get the transmission zero mobile with passband of constant absolute bandwidth and two
Point；When filter work in OFF state, can optimize and change by the variable capacitance in feed structure with interior isolation
Into.
Detailed description of the invention
The present invention will be further described below with reference to the drawings.
Fig. 1 is reconfigurable filter structure chart.
Fig. 2 is variable capacitanceC vi (i=1 or 2) circuit diagram.
Fig. 3 is simulation result of the reconfigurable filter at ON and OFF state.
Fig. 4 is to work asC v1Constant (being fixed on 0.5pF) changesC v2The S simulation parameter of acquisition.
Fig. 5 be filter work ON state (V p =0 V) under emulation and test result.
Fig. 6 be filter work OFF state (V p =0.8 V) under the test result that optimizes.
Specific embodiment
The present invention will be further described in the following with reference to the drawings and specific embodiments.
As shown in Figure 1, the present embodiment reconfigurable filter, comprising: there is stacked metal floor and medium substrate, two
It is a intercouple be loaded with the switching circuit and variable capacitance realized by PIN diodeλ/ 4 resonators (uniform impedance resonance
Device) 1,2, incoming feeder 3 and output feeder 4 and corresponding minor matters 5,6.λ/ 4 resonators 1,2, incoming feeder 3 and output feeder 4
And corresponding minor matters 5,6 are made of microstrip line.
λOne end of/4 resonators 1,2 is grounded, another to terminate the switching circuit realized by PIN diode.3 He of incoming feeder
The minor matters 5,6 for intercoupling are provided between output feeder 4.As shown in Figure 1, the switching circuit realized by PIN diode
Including withλThe capacitance that one end of/4 resonators is sequentially connected in seriesC p And PIN diode, the minus earth of PIN diode,
The anode of PIN diode is by radio-frequency choke inductance RFC2 connection one for controlling the bias voltage of PIN diode on-offV p ；?λThe specific location of/4 resonators 1,2 loads variable capacitanceC v1Ground connection；The end of incoming feeder 3 and output feeder 4
End with it is correspondingλPass through variable capacitance respectively between/4 resonators 1,2C v2It is connected.In the present embodiment, variable capacitanceC vi(i =
1 or 2) circuit theory is as shown in Fig. 2, include concatenated varactorC ai (C a1WithC a2Value range it is different) and every
Straight capacitorC bi (C b1WithC b2Value range it is different), varactor diodeC ai Plus earth, adjustable voltageV ci Through penetrating
Frequency choke coil RFC2 connection varactorC ai Cathode.
In the present embodiment,λ/ 4 resonators 1,2, incoming feeder 3, output feeder 4 and corresponding minor matters 5,6 and two by
Switching circuit and four variable capacitances that PIN diode is realized are all set in the upper surface of medium substrate, variable capacitanceC v1Connect
Ground terminal is in electrical contact by the metal throuth hole and metal floor of perforation medium substrate；In the switching circuit realized by PIN diode,
The cathode of PIN diode is in electrical contact by the metal throuth hole and metal floor of perforation medium substrate.
In this reconfigurable filter, Novel resonator loading scheme is used, i.e., by variable capacitance and by PIN diode reality
Existing switching circuit is loaded into a resonator simultaneously, the variable capacitanceC v1Load existsλ/ 4 resonator specific positions, by
The switching circuit load that PIN diode is realized existsλ/ 4 resonator one end.
Based on above scheme, a micro-strip reconfigurable filter is devised, which has constant exhausted under ON state
To bandwidth and highly selective tunable passband, there is high isolation in OFF state.As shown in Figure 1, wherein loading in resonator spy
Position the variable capacitance setC v1It is to load the switch realized by PIN diode in resonator one end for tuning fundamental frequency
Switchable, the variable capacitance between connection resonator and feeder line of circuit control passbandC v2In addition to for adjusting under passband ON state
External sort factor, it may also be used for improve passband OFF state under with interior isolation.In addition, introducing coupling between source and load
It closes to generate two transmission zeros, to improve passband selectivity.
When the bias voltage of switching circuitV p When being set as 0V, PIN diode is closed, resonator one end open circuit.At this
In the case of kind, filter is on state and band connection frequency is adjustable.In order to keep constant absolute bandwidth, two resonators
Between the coefficient of coup (K 12) and external sort factor (Q e) should be close to ideal value in entire frequency adjustable extent.Initial design
The constant absolute bandwidth of reconfigurable filter is 51MHz, is based on low-pass prototype,K 12WithQ eIdeal value can calculate.It is rightK 12And
Speech, it is mainly by coupling regime and coupling gapgInfluence, by selecting suitable coupling section that can makeK 12Close to ideal
Value；It is rightQ eFor, by adjustingC v2Value, makeQ eIt can be in entire frequency tuning range close to ideal value.In addition, in order to improve
The selectivity of passband introduces coupling between source and load and (loads two branches to intercouple between input, output feeder
Section) so as to the transmission zero mobile with passband in the generation of passband two sides.
When the bias voltage of switching circuitV p When being set as 0.8V, PIN diode conducting, the both ends of resonator are all grounded,
Resonance frequency shifts, and filter is in OFF state in the frequency adjustable extent of design.Fig. 3 shows frequency tuning mistake
Bifurcation (filter ON and OFF state) S parameter in journey.It can be seen from the figure that byC v1WithC v2Control any frequency can
Passband is adjusted, can be closed well in the off condition, and what is emulated in interested frequency range is better than with interior isolation
37dB。
There are the transmission paths that two are used for radiofrequency signal under passband OFF state.First is coupling between source and load
It closes, second isλCoupling between/4 resonators.And in second path,C v2In addition to for adjusting under passband ON stateQ e(as described in above-mentioned part), it can also be used to improve under passband OFF state with interior isolation.In order to clearly illustrate this change
Change, the passband (line with square symbols) of highest frequency (0.8GHz) work in the off condition in Fig. 3 selected to optimize,
As shown in figure 4, working asC v2When changing to 2.2 pF from 0.74 pF, 0.8GHz's improves with interior isolation (from 37.4dB to 47.3dB)
About 10 dB.So passing through tuningC v2, can obtain in interested frequency tuning range and be isolated in good band.Therefore,C v2It serves a dual purpose in reconfigurable filter design, it not only can control the tunable passband of filter ON stateQ e, and
And can improve filter OFF state with interior isolation.
Fig. 5 is emulation and test result of the present embodiment reconfigurable filter under ON state.Fig. 6 is that the present embodiment can weigh
The test result that structure filter optimizes in the off condition.
Reconfigurable filter is under ON state, centre frequency adjustable extent are as follows: 0.566-785GHz；3 dB bandwidth are as follows:
51 ± 2 MHz；Insertion loss are as follows: 4.08-2.52dB；There are two the transmission zeros mobile with passband for tool.
Reconfigurable filter is in the off condition: it is with interior isolation: > 43dB.
In addition to the implementation, the present invention can also have other embodiments.It is all to use equivalent substitution or equivalent transformation shape
At technical solution, fall within the scope of protection required by the present invention.
Claims (9)
1. a kind of can reconcile the reconfigurable filter of switchable function with passband, comprising: two couplings are loaded with by PIN bis-
The switching circuit and variable capacitance that pole pipe is realizedC v1Quarter-wave (λ/ 4) resonator, incoming feeder and output feeder；Institute
It statesλOne end of/4 resonators is grounded, another to terminate the switching circuit realized by PIN diode, realization pairλ/ 4 resonator basic modes
Control；Load the variable capacitance in resonator specific positionC v1ForλThe tuning of/4 resonator basic modes；The end of the incoming feeder
End and output feeder end with it is correspondingλPass through variable capacitance between/4 resonatorsC v2It is connected.
2. reconfigurable filter according to claim 1, it is characterised in that: the reconfigurable filter has used novel humorous
Shake device loading scheme, i.e., by variable capacitanceC v1With the switching circuit realized by PIN diode while being loaded into a resonator,
The variable capacitanceC v1Load existsλ/ 4 resonator specific positions, the switching circuit load realized by PIN diode existλ/ 4 resonance
Device one end.
3. reconfigurable filter according to claim 2, it is characterised in that: when load existsλThe switch of/4 resonator one end
When circuit disconnects, obtain tunableλThe band connection frequency of/4 resonators, filter is tunable, loads in resonator specific position
Variable capacitanceC v1For adjusting the fundamental frequency of filter, the variable capacitance of feeder line resonator is connectedC v2It is outer for adjusting
Component prime factor is to meet constant absolute bandwidth requirement.
4. reconfigurable filter according to claim 2, it is characterised in that: when load existsλThe switch of/4 resonator one end
When circuit is connected, resonator both ends, which are all grounded, (to be becomeλ/ 2 resonators), resonance frequency shifts, in designed frequency range
Filter is closed, and when load is in the variable capacitance of resonator specific positionC v1When constant, by adjust connection feeder line and
The variable capacitance of resonatorC v2Can Optimal Filter with interior isolation.
5. reconfigurable filter according to claim 1, it is characterised in that: set between the incoming feeder and output feeder
It is equipped with the minor matters for intercoupling.
6. reconfigurable filter according to claim 1, it is characterised in that: describedλ/ 4 resonators, incoming feeder and output
Feeder line and corresponding minor matters are made of microstrip line.
7. reconfigurable filter according to claim 1, it is characterised in that: have stacked metal floor and medium base
Plate, it is describedλ/ 4 resonators, incoming feeder, output feeder and corresponding minor matters and two switches realized by PIN diode
Circuit and four variable capacitances are all set in the upper surface of medium substrate, the variable capacitanceC v1Ground terminal by perforation medium
The metal throuth hole and metal floor of substrate are in electrical contact；In the described switching circuit by PIN diode realization, PIN diode
Cathode is in electrical contact by the metal throuth hole and metal floor of perforation medium substrate.
8. reconfigurable filter according to claim 1, it is characterised in that: incoming feeder and output feeder are L-shaped.
9. reconfigurable filter according to claim 1, it is characterised in that: describedλ/ 4 resonators are uniform impedance resonance
Device.
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| CN201910204009.7A CN109921761B (en) | 2019-03-18 | 2019-03-18 | Reconfigurable filter with passband adjustable and switchable functions |
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| CN109921761B CN109921761B (en) | 2023-05-05 |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111146536A (en) * | 2019-12-25 | 2020-05-12 | 南通大学 | Fixed high passageway frequency adjustable duplexer of low passageway frequency |
| CN113013566A (en) * | 2021-03-21 | 2021-06-22 | 南通大学 | Switchable microstrip double balun |
| CN113285193A (en) * | 2021-04-20 | 2021-08-20 | 武汉德威斯电子技术有限公司 | Zero-point adjustable frequency hopping filter |
| CN113851845A (en) * | 2021-10-13 | 2021-12-28 | 中国信息通信研究院 | Integrated filtering duplex antenna for inhibiting in-band signal |
| CN114257213A (en) * | 2021-12-08 | 2022-03-29 | 电子科技大学 | Adjustable band-pass tuning frequency selection circuit, electrically tunable filter and adjusting method thereof |
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| CN108493533A (en) * | 2018-05-21 | 2018-09-04 | 南通大学 | It is a kind of that there is the tunable filter for stablizing Wide stop bands |
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| CN105720339A (en) * | 2016-03-30 | 2016-06-29 | 华南理工大学 | Dual-band adjustable band-pass filter |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111146536A (en) * | 2019-12-25 | 2020-05-12 | 南通大学 | Fixed high passageway frequency adjustable duplexer of low passageway frequency |
| CN111146536B (en) * | 2019-12-25 | 2021-02-02 | 南通大学 | Duplexer with fixed low channel frequency and adjustable high channel frequency and design method |
| CN113013566A (en) * | 2021-03-21 | 2021-06-22 | 南通大学 | Switchable microstrip double balun |
| CN113013566B (en) * | 2021-03-21 | 2022-01-28 | 南通大学 | Switchable microstrip double balun |
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| CN113851845A (en) * | 2021-10-13 | 2021-12-28 | 中国信息通信研究院 | Integrated filtering duplex antenna for inhibiting in-band signal |
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| CN114257213A (en) * | 2021-12-08 | 2022-03-29 | 电子科技大学 | Adjustable band-pass tuning frequency selection circuit, electrically tunable filter and adjusting method thereof |
| CN114257213B (en) * | 2021-12-08 | 2023-10-20 | 电子科技大学 | Adjustable band-pass tuning frequency-selecting circuit, electrically tunable filter and adjusting method thereof |
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| CN109921761B (en) | 2023-05-05 |
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