CN104795612A - Three-notch ultra-wideband filter based on defected microstrip structures - Google Patents
Three-notch ultra-wideband filter based on defected microstrip structures Download PDFInfo
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- CN104795612A CN104795612A CN201410023986.4A CN201410023986A CN104795612A CN 104795612 A CN104795612 A CN 104795612A CN 201410023986 A CN201410023986 A CN 201410023986A CN 104795612 A CN104795612 A CN 104795612A
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Abstract
The invention provides a three-notch ultra-wideband filter based on defected microstrip structures, which comprises a microstrip substrate, and a first input/output port, a second input/output port, a first uniform line transmission unit, a second uniform line transmission unit, a first parallel coupled feeder, a second parallel coupled feeder and an E-type multimode resonant structure arranged on the microstrip substrate, wherein a first defected microstrip structure, a second defected microstrip structure and a third defected microstrip structure are arranged on the E-type multimode resonant structure; and each defected microstrip structure is formed by three linear grooves connected in sequence and with the same width in the E-type multimode resonant structure. Three-notch features are provided, the central frequency of the notch is adjustable through adjusting the length of the defected microstrip structure, and product debugging and batch production are facilitated.
Description
Technical field
The invention belongs to microwave transmission device technical field, be specifically related to a kind of three trap ultra-wide band filters based on defected microstrip structure.
Background technology
Ultra broadband (Ultra-wideband, UWB) technology is, the advantage such as power consumption little, message transmission rate high, fail safe good low with its cost and become a kind of wireless communication technology emerging in the world in recent years.From 2002 FCC (Federal Communications Commission, FCC) by the frequency range of 3.1GHz ~ 10.6GHz approval be used for business correspondence since, Ultra-wideband Communication Technology receives increasing attention.Filter is a critical elements in radio ultra wide band system, how to design compact conformation, and ultra wide band bandpass filter of good performance is own through becoming the target that researchers chase.But, within the scope of whole ultra wideband frequency, owing to there is other various narrowband wireless communication signal, such as 5.2/5.8GHz WLAN signal and 8.0GHz satellite communication system signal etc.And these wireless communication signals meeting severe jamming radio ultra wide band system, in order to suppress the mutual interference between different system, ensure that radio ultra wide band system normally works, active demand has the high performance mini ultra-wide band filter of multifrequency trap characteristic.
Following existing bibliographical information has the ultra-wide band filter structure of trap characteristic:
Document 1(Shaman, H., and J.S.Hong, Asymmetric Parallel-Coupled Lines for NotchImplementation in UWB Filters, IEEE Microwave and Wireless Components Letters, 2007, loading open circuit detail on parallel coupled line is utilized to obtain trap characteristic 17:516-3518), but this method makes ultra-wide band filter only obtain a notch band, and the centre frequency of this notch band and bandwidth not easily regulate;
Document 2(Hao, Z.C., and J.S.Hong, Compact UWB Filter With Double Notch-BandsUsing Multilayer LCP Technology, IEEE Microwave and Wireless Components Letters, 2009, to utilize between sandwich construction 19:500-502) broadside coupled realizes two trap characteristic, but sandwich construction is not easily applied to microwave circuit, and cost of manufacture is expensive, is not easy to volume production;
Document 3(Wei, F., W.T.Li, X.W.Shi, and Q.L.Chen., Compact UWB Bandpass Filterwith Triple-notched Bands Using Stepped Impedance Resonator, IEEE Microwave andWireless Components Letters, 2012, there is the step electric impedance resonator of three module features to initial ultra-wide band filter by coupling 22:512-514), obtain required three trap characteristics, but adds additional the size of initial circuit.
In sum, the ultra-wide band filter with trap characteristic of design in document 1, structure is simple, but only obtains a notch band; In document 2, the ultra-wide band filter of two trap characteristics of design is based on multilayer circuit structure, but because cost of manufacture is expensive and technology imperfection, is unfavorable for volume production; The ultra-wide band filter of three trap characteristics of the single layer structure of design in document 3, is easy to processing and integrated, but the selectivity of passband and stopband characteristic undesirable, and the centre frequency of this notch band and bandwidth not easily regulate.
Summary of the invention
The object of the present invention is to provide a kind of three trap ultra-wide band filters based on defected microstrip structure, it has three trap characteristics and can realize the adjustable of trap centre frequency by regulating the length of defected microstrip structure, is convenient to production debugging and batch production.
In order to achieve the above object, realizing technical solution of the present invention is:
Based on three trap ultra-wide band filters of defected microstrip structure, comprise micro-belt substrate, the reverse side of micro-belt substrate is as grounding plate, the both sides of micro-belt substrate be distributed with the first input output port and the second input output port, the front of micro-belt substrate is provided with the first uniform line transmission unit, the second uniform transmission line unit, the first parallel coupling feeder line, the second parallel coupling feeder line, E type multimode resonance structure;
Described first uniform transmission line unit, the second uniform transmission line unit input with first respectively output port and second input output port be connected, and the first uniform transmission line unit, the second uniform transmission line unit, first input output port and second input output port be on same level line;
Described first parallel coupling feeder line and the second parallel coupling feeder line are respectively in " [" shape and "] " shape, and the openend of the first parallel coupling feeder line arranges in opposite directions with the openend of the second parallel coupling feeder line and is all connected with the center minor matters of E type multimode resonance structure; The non-openend of the first parallel coupling feeder line is connected with the first uniform transmission line unit, and the non-openend of the second parallel coupling feeder line is connected with the second uniform transmission line unit;
E type multimode resonance structure offers the first defected microstrip structure, the second defected microstrip structure, the 3rd defected microstrip structure; First defected microstrip structure, the second defected microstrip structure and the 3rd defected microstrip structure connect successively by three articles that are opened on E type multimode resonance structure and the identical linear groove of width is formed, and the linear groove at two ends is all with the linear groove vertical of centre and the same side of the linear groove mediated; The middle straight linear grooves of the first defected microstrip structure, the second defected microstrip structure and the 3rd defected microstrip structure is parallel mutually.
The present invention compared with prior art, its remarkable advantage is: utilize new E type multimode resonance structure of the present invention to obtain the ultra-wide band filter of covering ultra wideband communications band 3.1 ~ 10.6GHz, realizes this filter and has selectivity and Out-of-band rejection effect in good band; The length changing the first defected microstrip structure realizes the regulable center frequency of the first notch band, the length changing the second defected microstrip structure realizes the regulable center frequency of the second notch band, and the length changing the 3rd defected microstrip structure realizes the regulable center frequency of the 3rd notch band; The bandwidth that the width changing the first defected microstrip structure realizes the first notch band is adjustable, the bandwidth that the width changing the second defected microstrip structure realizes the second notch band is adjustable, and the bandwidth that the width changing the 3rd defected microstrip structure realizes the 3rd notch band is adjustable; The structure of ultra-wide band filter is simple, handling ease, and production cost is low and be convenient to debugging.
Accompanying drawing explanation
Fig. 1 is the schematic perspective view of the three trap ultra-wide band filters that the present invention is based on defected microstrip structure.
Fig. 2 is the front schematic view of the three trap ultra-wide band filters that the present invention is based on defected microstrip structure.
Fig. 3 is the frequency response characteristic simulation curve of the present invention with the first defected microstrip structure length variations.
Fig. 4 is the frequency response characteristic simulation curve of the present invention with the second defected microstrip structure length variations.
Fig. 5 is the frequency response characteristic simulation curve of the present invention with the 3rd defected microstrip structure length variations.
Fig. 6 is the emulation of the present invention three trap ultra-wide band filter frequency response characteristic and object test curve.
Embodiment
As shown in Figure 1, the present invention three trap ultra-wide band filter comprises micro-belt substrate 11, and the reverse side of micro-belt substrate 11 is as the grounding plate of three trap ultra-wide band filters; The both sides of micro-belt substrate 11 be distributed with two inputs output port, namely the first input output port 1 and the second input output port 2.
As depicted in figs. 1 and 2, the front of micro-belt substrate 11 is provided with the first uniform line transmission unit 3, second uniform transmission line unit 4, first parallel coupling feeder line 5, second parallel coupling feeder line 6, E type multimode resonance structure 10.
Described first uniform transmission line unit 3, second uniform transmission line unit 4 input with first respectively output port 1 and second input output port 2 be connected, and the first uniform transmission line unit 3, second uniform transmission line unit 4, first input output port 1 and the second input output port 2 be on same level line.
Described first parallel coupling feeder line 5 and the second parallel coupling feeder line 6 are respectively in " [" shape and "] " shape, and the openend of the first parallel coupling feeder line 5 arranges in opposite directions with the openend of the second parallel coupling feeder line 6 and is all connected with the center minor matters 12 of E type multimode resonance structure 10; The non-openend of the first parallel coupling feeder line 5 is connected with the first uniform transmission line unit 3, and the non-openend of the second parallel coupling feeder line 6 is connected with the second uniform transmission line unit 4.
E type multimode resonance structure 10 offers the first defected microstrip structure 7, second defected microstrip structure 8, the 3rd defected microstrip structure 9; First defected microstrip structure 7, second defected microstrip structure 8 and the 3rd defected microstrip structure 9 connect successively by three articles that are opened on E type multimode resonance structure 10 and the identical linear groove of width is formed, and the linear groove at two ends is all with the linear groove vertical of centre and the same side of the linear groove mediated; The middle straight linear grooves of the first defected microstrip structure 7, second defected microstrip structure 8 and the 3rd defected microstrip structure 9 is parallel mutually.
The present invention passes through to introduce the first defected microstrip structure 7, second defected microstrip structure 8 in traditional E type multimode resonance structure, the 3rd defected microstrip structure 9 forms the novel E type multimode resonance structure 10 of the present invention, first defected microstrip structure 7, second defected microstrip structure 8, the 3rd defected microstrip structure 9 are equivalent to three independently half-wave resonator, thus obtain three sunken characteristic ripples; By the first parallel coupling feeder line 5, E type multimode resonance structure 10 and the second parallel coupling feeder line 6 cascade being obtained the ultra-wide band filter with two transmission zeros, achieving passband has reasonable frequency selectivity.Therefore, the present invention obtains three trap ultra-wide band filters when not increasing original circuit size.
The present invention is by the centre frequency of length adjustment first defected microstrip structure 7 of change first defected microstrip structure 7, and the length especially by the linear groove at change first defected microstrip structure 7 two ends realizes.
The present invention is by the centre frequency of length adjustment second defected microstrip structure 8 of change second defected microstrip structure 8, and the length especially by the linear groove at change second defected microstrip structure 8 two ends realizes.
The present invention is by the centre frequency of length adjustment the 3rd defected microstrip structure 9 of change the 3rd defected microstrip structure 9, and the length especially by the linear groove at change the 3rd defected microstrip structure 9 two ends realizes.
The present invention covers band bandwidth by the trap that change first defected microstrip structure 7, second defected microstrip structure 8, width adjustment first defected microstrip structure 7, second defected microstrip structure 8 of the 3rd defected microstrip structure 9 and the 3rd defected microstrip structure 9 are respective, and the width especially by three articles of linear grooves of change first defected microstrip structure 7, second defected microstrip structure 8, the 3rd defected microstrip structure 9 realizes.
When the width of three linear grooves of the first defected microstrip structure 7 is 0.1mm, when the length of the linear groove at two ends is 18mm, it is 5.15-5.25GHz that the trap of the first defected microstrip structure 7 covers frequency range.
When the width of three linear grooves of the second defected microstrip structure 8 is 0.1mm, when the length of the linear groove at two ends is 16.6mm, it is 5.75-5.85GHz that the second defected microstrip structure 8 trap covers frequency range.
When the width of three articles of linear grooves of the 3rd defected microstrip structure 9 is 0.1mm, when the length of the linear groove at two ends is 12.3mm, it is 7.90-8.10GHz that the 3rd defected microstrip structure 9 trap covers frequency range.
Described E type multimode resonance structure 10 forms by T-shaped bimodulus resonance structure is folding.
Preferably, the dielectric constant of described micro-belt substrate 11 is 3.38, and thickness is 0.813mm, and loss angle is 0.0027.
Beneficial effect of the present invention can be further illustrated by following emulation experiment:
Experiment one: utilize the three trap ultra-wide band filters of Frequency Simulation Software Ansoft HFSS11.0 to first defected microstrip structure 7 with different length to carry out frequency response characteristic emulation, frequency response characteristic comprises: S21(insertion loss) parameter.
As shown in Figure 3, abscissa represents frequency component to simulation result, and unit is GHz, and ordinate represents amplitude variations, and unit is dB.As can be seen from Figure 3, by changing the length of the first defected microstrip structure 7, the regulable center frequency of first trap can be realized.
Experiment two: the frequency response characteristic emulation utilizing the three trap ultra-wide band filters of Frequency Simulation Software Ansoft HFSS11.0 to second defected microstrip structure 8 with different length to carry out, frequency response characteristic comprises: S21(insertion loss) parameter.
As shown in Figure 4, in Fig. 4, abscissa represents frequency component to simulation result, and unit is GHz, and ordinate represents amplitude variations, and unit is dB.As can be seen from Figure 4, change the length of the second defected microstrip structure 8, the regulable center frequency of second trap can be realized.
Experiment three: the frequency response characteristic emulation utilizing the three trap ultra-wide band filters of Frequency Simulation Software Ansoft HFSS11.0 to the 3rd defected microstrip structure 9 with different length to carry out, frequency response characteristic comprises: S21(insertion loss) parameter.
As shown in Figure 5, in Fig. 5, abscissa represents frequency component to simulation result, and unit is GHz, and ordinate represents amplitude variations, and unit is dB.As can be seen from Figure 5, change the length of the linear groove at the 3rd defected microstrip structure 9 two ends, the regulable center frequency of the 3rd trap can be realized.
Experiment four: utilize Frequency Simulation Software Ansoft HFSS11.0 to having the first defected microstrip structure 7, second defected microstrip structure 8 of designated length, three trap ultra-wide band filters of the 3rd defected microstrip structure 9 carry out frequency response characteristic emulation and utilize vector network analyzer Agilent N5244A to carry out object test, frequency characteristic comprises: S21(insertion loss) parameter and S11(return loss) parameter.
As shown in Figure 6, in Fig. 6, abscissa represents frequency component to simulation result, and unit is GHz, and left side ordinate represents amplitude variations, and unit is dB.As can be seen from Figure 6, at centre frequency 5.2GHz, 5.8GHz, 8.0GHz place, there is trap characteristic, trap amplitude is all greater than 15dB, can WLAN(5.15-5.25GHz, 5.75-5.85GHz be covered), Satellite communication(7.90-8.10GHz) three interference bands, there are two transmission zeros to realize this filter at frequency 2.0GHz, 10.9GHz place and there is good selectivity, and the Out-of-band rejection characteristic of ultra-wide band filter is fine, the suppression of-10dB can reach 17GHz.
Claims (10)
1. based on three trap ultra-wide band filters of defected microstrip structure, comprise micro-belt substrate (11), the reverse side of micro-belt substrate (11) is as grounding plate, the both sides of micro-belt substrate (11) be distributed with respectively the first input output port (1) and the second input output port (2), it is characterized in that, be provided with the first uniform transmission line unit (3), the second uniform transmission line unit (4), the first parallel coupling feeder line (5), the second parallel coupling feeder line (6), E type multimode resonance structure (10) in the front of micro-belt substrate (11);
Described first uniform transmission line unit (3) and the second uniform transmission line unit (4) input with first respectively output port (1) and second input output port (2) be connected, and the first uniform transmission line unit (3), the second uniform transmission line unit (4), first input output port (1) and second input output port (2) be all on same level line;
Described first parallel coupling feeder line (5) and the second parallel coupling feeder line (6) are respectively in " [" shape and "] " shape, and the openend of the first parallel coupling feeder line (5) arranges in opposite directions with the openend of the second parallel coupling feeder line (6) and is all connected with the center minor matters (12) of E type multimode resonance structure (10); The non-openend of the first parallel coupling feeder line (5) is connected with the first uniform transmission line unit (3), and the non-openend of the second parallel coupling feeder line (6) is connected with the second uniform transmission line unit (4);
E type multimode resonance structure (10) offers the first defected microstrip structure (7), the second defected microstrip structure (8), the 3rd defected microstrip structure (9); First defected microstrip structure (7), the second defected microstrip structure (8) and the 3rd defected microstrip structure (9) connect successively by three articles that are opened in E type multimode resonance structure (10) and the identical linear groove of width is formed, and the linear groove at two ends is all with the linear groove vertical of centre and the same side of the linear groove mediated; The middle straight linear grooves of the first defected microstrip structure (7), the second defected microstrip structure (8) and the 3rd defected microstrip structure (9) is parallel mutually.
2., as claimed in claim 1 based on three trap ultra-wide band filters of defected microstrip structure, it is characterized in that, by changing the centre frequency of length adjustment first defected microstrip structure (7) of the linear groove at the first defected microstrip structure (7) two ends.
3., as claimed in claim 1 based on three trap ultra-wide band filters of defected microstrip structure, it is characterized in that, by changing the centre frequency of length adjustment second defected microstrip structure (8) of the linear groove at the second defected microstrip structure (8) two ends.
4., as claimed in claim 1 based on three trap ultra-wide band filters of defected microstrip structure, it is characterized in that, by changing the centre frequency of the length adjustment the 3rd defected microstrip structure (9) of the linear groove at the 3rd defected microstrip structure (9) two ends.
5. as claimed in claim 1 based on three trap ultra-wide band filters of defected microstrip structure, it is characterized in that, covering band bandwidth by changing the respective trap of width adjustment first defected microstrip structure (7) of three articles of linear grooves of the first defected microstrip structure (7), the second defected microstrip structure (8) and the 3rd defected microstrip structure (9), the second defected microstrip structure (8) and the 3rd defected microstrip structure (9).
6., as claimed in claim 1 based on three trap ultra-wide band filters of defected microstrip structure, it is characterized in that, the width of three linear grooves of described first defected microstrip structure (7) is 0.1mm, and the length of the linear groove at two ends is 18mm.
7., as claimed in claim 1 based on three trap ultra-wide band filters of defected microstrip structure, it is characterized in that, the width of three linear grooves of described second defected microstrip structure (8) is 0.1mm, and the length of the linear groove at two ends is 16.6mm.
8., as claimed in claim 1 based on three trap ultra-wide band filters of defected microstrip structure, it is characterized in that, the width of three articles of linear grooves of described 3rd defected microstrip structure (9) is 0.1mm, and the length of the linear groove at two ends is 12.3mm.
9. as claimed in claim 1 based on three trap ultra-wide band filters of defected microstrip structure, it is characterized in that, described E type multimode resonance structure (10) forms by T-shaped bimodulus resonance structure is folding.
10., as claimed in claim 1 based on three trap ultra-wide band filters of defected microstrip structure, it is characterized in that, the dielectric constant of described micro-belt substrate 11 is 3.38, and thickness is 0.813mm, and loss angle is 0.0027.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106981707A (en) * | 2016-12-19 | 2017-07-25 | 北京航天测控技术有限公司 | A kind of novel miniaturization wideband microband bandpass filter |
| CN111129674A (en) * | 2019-12-27 | 2020-05-08 | 上海海事大学 | Three-trapped wave ultra wide band-pass filter based on E-type resonator |
| US11228077B2 (en) | 2019-06-17 | 2022-01-18 | Carrier Corporation | Microstrip DC block |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1329977A1 (en) * | 2002-01-17 | 2003-07-23 | Paratek Microwave, Inc. | Electronically tunable combline filter with asymmetric response |
| US20070194864A1 (en) * | 2006-02-03 | 2007-08-23 | Samsung Electronics Co., Ltd. | DC block with band-notch characteristics using DGS |
| CN101950827A (en) * | 2010-09-06 | 2011-01-19 | 华东交通大学 | Branch node loaded ultra wideband microwave filter |
| KR20110118280A (en) * | 2010-04-23 | 2011-10-31 | 인천대학교 산학협력단 | Miniaturized zero-order-resonant metamaterial bandpass filter for the uwb lower-half-band with open-stub inserted non-uniform interdigital coupled lines |
| CN103187599A (en) * | 2013-03-09 | 2013-07-03 | 西安电子科技大学 | Band-gap adjustable micro-strip ultra-wide band filter |
-
2014
- 2014-01-18 CN CN201410023986.4A patent/CN104795612A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1329977A1 (en) * | 2002-01-17 | 2003-07-23 | Paratek Microwave, Inc. | Electronically tunable combline filter with asymmetric response |
| US20070194864A1 (en) * | 2006-02-03 | 2007-08-23 | Samsung Electronics Co., Ltd. | DC block with band-notch characteristics using DGS |
| KR20110118280A (en) * | 2010-04-23 | 2011-10-31 | 인천대학교 산학협력단 | Miniaturized zero-order-resonant metamaterial bandpass filter for the uwb lower-half-band with open-stub inserted non-uniform interdigital coupled lines |
| CN101950827A (en) * | 2010-09-06 | 2011-01-19 | 华东交通大学 | Branch node loaded ultra wideband microwave filter |
| CN103187599A (en) * | 2013-03-09 | 2013-07-03 | 西安电子科技大学 | Band-gap adjustable micro-strip ultra-wide band filter |
Non-Patent Citations (2)
| Title |
|---|
| JIANGPENG WANG,ETL: "Compact UWB bandpass filter with triple notched bands using parallel U-shaped defected microstrip structure", 《IET ELECTRONICS LETTERS》 * |
| 赵俊顶，王建朋，陶子文: "一种具有双陷波特性的超宽带带通滤波器设计", 《2013年全国微波毫米波会议》 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106981707A (en) * | 2016-12-19 | 2017-07-25 | 北京航天测控技术有限公司 | A kind of novel miniaturization wideband microband bandpass filter |
| US11228077B2 (en) | 2019-06-17 | 2022-01-18 | Carrier Corporation | Microstrip DC block |
| CN111129674A (en) * | 2019-12-27 | 2020-05-08 | 上海海事大学 | Three-trapped wave ultra wide band-pass filter based on E-type resonator |
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Application publication date: 20150722 |