CN117013222A - Miniaturized balanced low-pass filter with wide stop band characteristic - Google Patents
Miniaturized balanced low-pass filter with wide stop band characteristic Download PDFInfo
- Publication number
- CN117013222A CN117013222A CN202311081444.8A CN202311081444A CN117013222A CN 117013222 A CN117013222 A CN 117013222A CN 202311081444 A CN202311081444 A CN 202311081444A CN 117013222 A CN117013222 A CN 117013222A
- Authority
- CN
- China
- Prior art keywords
- double
- sided
- line
- impedance transmission
- low
- 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.)
- Pending
Links
- 230000005540 biological transmission Effects 0.000 claims abstract description 83
- 230000001629 suppression Effects 0.000 claims abstract description 46
- 230000008878 coupling Effects 0.000 claims abstract description 24
- 238000010168 coupling process Methods 0.000 claims abstract description 24
- 238000005859 coupling reaction Methods 0.000 claims abstract description 24
- 238000004891 communication Methods 0.000 description 3
- 230000005284 excitation Effects 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- 238000013461 design Methods 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 230000005764 inhibitory process Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
- H01P1/00—Auxiliary devices
- H01P1/20—Frequency-selective devices, e.g. filters
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
- H01P1/00—Auxiliary devices
- H01P1/20—Frequency-selective devices, e.g. filters
- H01P1/201—Filters for transverse electromagnetic waves
- H01P1/203—Strip line filters
- H01P1/2039—Galvanic coupling between Input/Output
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Control Of Motors That Do Not Use Commutators (AREA)
Abstract
The application discloses a miniaturized balanced low-pass filter with wide stop band characteristics, which comprises: the device comprises a differential structure double-sided parallel strip line input port A, a differential structure double-sided parallel strip line output port B, two groups of reversed phase connection structures, two sections of double-sided high-impedance transmission lines, two sections of double-sided terminal open-circuit harmonic suppression lines, two sections of double-sided low-impedance transmission lines, one section of double-sided parallel coupling lines, one section of double-sided terminal open-circuit harmonic resonance lines and a dielectric plate. Besides the function of suppressing common mode noise, the balanced low-pass filter has the characteristics of high selectivity, wide stop band suppression and the like for the input differential mode signals, and has the characteristics of simple structure, small circuit size and the like, and solves the problems of large circuit size, poor filter selectivity, poor out-of-band suppression, incapability of suppressing common mode noise and the like of the conventional low-pass filter.
Description
Technical Field
The application relates to a balanced low-pass filter, in particular to a miniaturized balanced low-pass filter with wide stop band characteristics.
Background
In modern wireless communication systems, balancing circuits play an important role. Compared with an unbalanced single-port input/output circuit, the balanced circuit can efficiently suppress environmental noise and noise generated by an internal active device, and thus has excellent electromagnetic compatibility characteristics. A wide variety of rf microwave devices, such as filters, mixers, and power amplifiers, are used in balanced topologies. With the rapid development of integrated circuits, the need for balanced devices is becoming more stringent. The balance filter is required to have a filter characteristic at the time of differential mode signal input while being capable of effectively suppressing common mode noise. The balanced filter can be simply constructed by one single-port filter and two balun, but its area is huge. Therefore, it is an important problem to design the balance filter as a single device without adding additional balun.
With the rapid development of wireless communication technology, low-pass filters have received much attention as an integral part of wireless communication systems. The low pass filter may be used to remove spurious responses and unwanted harmonic interference due to the inherent characteristics of the nonlinear or distributed circuitry of the system. However, the research on the high-performance low-pass filter is not mature at present, and the existing low-pass filter has a plurality of problems of larger structure size, poor frequency selectivity, poor out-of-band rejection of the whole filter and the like. Furthermore, there is little research into balanced low-pass filters. Therefore, the research on the miniaturized low-pass filter capable of realizing broadband common-mode rejection, differential-mode high selectivity and wide stop-band rejection has important significance. In view of the foregoing, it is necessary to provide a miniaturized balanced low-pass filter with wide stop band characteristics.
Disclosure of Invention
Based on this, in order to solve the defect existing in the prior art, specially provided is a miniaturized balanced low-pass filter with wide stop band characteristics, the specific technical scheme includes: the device comprises a differential structure double-sided parallel strip line input port A, a differential structure double-sided parallel strip line output port B, two groups of reversed phase connection structures, two sections of double-sided high-impedance transmission lines, two sections of double-sided terminal open-circuit harmonic suppression lines, two sections of double-sided low-impedance transmission lines, a section of double-sided parallel coupling line, a section of double-sided terminal open-circuit resonance line and a dielectric plate;
the differential structure double-sided parallel strip line input port A comprises an input port A+ and an input port A-;
the differential structure double-sided parallel strip line output port B comprises an output port B+ and an output port B-;
the two groups of reverse phase connection structures comprise a reverse phase connection combination I and a reverse phase connection combination II; one end of the reverse phase connection combination I is connected with the input port A+, and the other end of the reverse phase connection combination I is connected with the connection part of the input port A-and the first double-sided high-impedance transmission line; one end of the reverse phase connection combination II is connected with the output port B+ and the other end of the reverse phase connection combination II is connected with the connection part of the output port B-and the second double-sided high-impedance transmission line;
the two sections of double-sided high-impedance transmission lines comprise a first double-sided high-impedance transmission line and a second double-sided high-impedance transmission line; one end of the first double-sided high-impedance transmission line is connected with the input port A-, and the other end of the first double-sided high-impedance transmission line is connected with the connection part of the first double-sided open-ended harmonic suppression line and the first double-sided low-impedance transmission line; one end of the second double-sided high-impedance transmission line is connected with the output port B-and the other end of the second double-sided open-ended harmonic suppression line is connected with the connection part of the second double-sided low-impedance transmission line;
the two-section double-sided open-ended harmonic suppression line comprises a first double-sided open-ended harmonic suppression line and a second double-sided open-ended harmonic suppression line; one end of the first double-sided open-ended harmonic suppression line is connected to the joint of the first double-sided high-impedance transmission line and the first double-sided low-impedance transmission line, and the other end of the first double-sided open-ended harmonic suppression line is open; one end of the second double-sided open-ended harmonic suppression line is connected to the joint of the second double-sided high-impedance transmission line and the first double-sided low-impedance transmission line, and the other end of the second double-sided open-ended harmonic suppression line is open;
the two-section double-sided low-impedance transmission line comprises a first double-sided low-impedance transmission line and a second double-sided low-impedance transmission line; one end of the first double-sided low-impedance transmission line is connected to the connection part of the first double-sided high-impedance transmission line and the first double-sided terminal open-circuit harmonic suppression line, and the other end of the first double-sided low-impedance transmission line is connected with the double-sided parallel coupling line; one end of the second double-sided low-impedance transmission line is connected to the connection part of the second double-sided high-impedance transmission line and the second double-sided terminal open-circuit harmonic suppression line, and the other end of the second double-sided low-impedance transmission line is connected with the double-sided parallel coupling line;
the port A of the double-sided parallel coupling line is connected with a first double-sided low-impedance transmission line, the port B of the double-sided parallel coupling line is connected with a second double-sided low-impedance transmission line, and the port C and the port D of the double-sided parallel coupling line are connected with a double-sided open-ended resonant line.
Further, the common mode rejection characteristic of the balanced low-pass filter is adjusted by adjusting the inverse connection combination I and the inverse connection combination II.
Further, the characteristic impedance and the electrical length of the first double-sided open-ended harmonic suppression line and the second double-sided open-ended harmonic suppression line are adjusted so as to realize the wide stop band suppression characteristic of the balanced low-pass filter.
Further, the passband bandwidth of the balanced low-pass filter is adjusted by adjusting the coupling coefficient of the double-sided parallel coupling lines.
Compared with the prior art, the application has the beneficial effects that:
in order to design a balanced filter as a single device and realize a miniaturized low-pass filter with high performance of a differential mode while realizing common mode rejection, the application provides a miniaturized balanced low-pass filter with wide stop band characteristics. Besides the function of suppressing common mode noise, the balanced low-pass filter has the characteristics of high selectivity, wide stop band suppression and the like for the input differential mode signals, and has the characteristics of simple structure, small circuit size and the like, and solves the problems of large circuit size, poor filter selectivity, poor out-of-band suppression, incapability of suppressing common mode noise and the like of the conventional low-pass filter.
Drawings
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments described in the present application, and other drawings may be obtained according to the drawings without inventive effort to those skilled in the art.
FIG. 1 is a schematic diagram of a miniaturized balanced low-pass filter with wide stopband characteristics according to the present application;
FIG. 2 is a graph of the magnitude of a hybrid S-parameter of a miniaturized balanced low-pass filter with wide stop band characteristics under differential mode signal excitation in accordance with the present application;
FIG. 3 is a graph of the magnitude of a hybrid S-parameter of a miniaturized balanced low-pass filter with wide stop band characteristics under common mode signal excitation in accordance with the present application;
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the present application more apparent, the technical solutions of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.
The application relates to a miniaturized balanced low-pass filter with wide stop band characteristics, which comprises: the double-sided parallel strip line input port A of the differential structure, the double-sided parallel strip line output port B of the differential structure, two groups of reversed phase connection structures, two sections of double-sided high-impedance transmission lines, two sections of double-sided open-ended harmonic suppression lines, two sections of double-sided low-impedance transmission lines, one section of double-sided parallel coupling line 13, one section of double-sided open-ended resonant line 14 and a dielectric plate 15;
the differential structure double-sided parallel strip line input port A comprises an input port A+1 and an input port A-2;
the differential structure double-sided parallel strip line output port B comprises an output port B+3 and an output port B-4;
the two groups of reverse phase connection structures comprise a reverse phase connection combination I5 and a reverse phase connection combination II 6; one end of the reverse phase connection combination I5 is connected with the input port A+1, and the other end of the reverse phase connection combination I is connected with the connection part of the input port A-2 and the first double-sided high-impedance transmission line 7; one end of the reverse phase connection combination II 6 is connected with the output port B+3, and the other end of the reverse phase connection combination II is connected with the connection part of the output port B-4 and the second double-sided high-impedance transmission line 8;
the two-section double-sided high-impedance transmission line comprises a first double-sided high-impedance transmission line 7 and a second double-sided high-impedance transmission line 8; one end of the first double-sided high-impedance transmission line 7 is connected with the input port A-2, and the other end of the first double-sided high-impedance transmission line is connected with the connection part of the first double-sided open-ended harmonic suppression line 9 and the first double-sided low-impedance transmission line 11; one end of the second double-sided high-impedance transmission line 8 is connected with the output port B-4, and the other end of the second double-sided open-ended harmonic suppression line 10 is connected with the connection part of the second double-sided low-impedance transmission line 12;
the two-section double-sided open-ended harmonic suppression line comprises a first double-sided open-ended harmonic suppression line 9 and a second double-sided open-ended harmonic suppression line 10; one end of the first double-sided open-ended harmonic suppression line 9 is connected to the connection part of the first double-sided high-impedance transmission line 7 and the first double-sided low-impedance transmission line 11, and the other end of the first double-sided open-ended harmonic suppression line is open; one end of the second double-sided open-ended harmonic suppression line 10 is connected to the connection part of the second double-sided high-impedance transmission line 8 and the first double-sided low-impedance transmission line 12, and the other end is open;
the two-section double-sided low impedance transmission line comprises a first double-sided low impedance transmission line 11 and a second double-sided low impedance transmission line 12; one end of the first double-sided low-impedance transmission line 11 is connected to the connection part of the first double-sided high-impedance transmission line 7 and the first double-sided open-ended harmonic suppression line 9, and the other end of the first double-sided low-impedance transmission line is connected with the double-sided parallel coupling line 13; one end of the second double-sided low-impedance transmission line 12 is connected to the connection part of the second double-sided high-impedance transmission line 8 and the second double-sided open-ended harmonic suppression line 10, and the other end is connected with the double-sided parallel coupling line 13;
the a port 1a of the double-sided parallel coupling line 13 is connected with the first double-sided low-impedance transmission line 11, the B port 1B of the double-sided parallel coupling line 13 is connected with the second double-sided low-impedance transmission line 12, and the C port 1C and the D port 1D of the double-sided parallel coupling line 13 are connected with the double-sided terminal open-circuit resonant line 14.
The common mode rejection characteristics of the balanced low pass filter are adjusted by adjusting the inverse connection combination I5 and the inverse connection combination II 6.
The wide stop band rejection characteristics of the balanced low pass filter are achieved by adjusting the characteristic impedance and electrical length of the first and second double-sided open ended harmonic rejection lines 9 and 10.
The passband bandwidth of the balanced low pass filter is adjusted by adjusting the coupling coefficient of the double-sided parallel coupled lines 13.
In order to further explain the miniaturized balanced low-pass filter with wide stopband characteristics provided by the application, the following specific examples are implemented on the premise of the technical scheme of the application, but the protection scope of the application is not limited to the following examples, and all the methods used in the following examples are conventional methods unless otherwise specified.
Specific examples: this example illustrates a miniaturized balanced low pass filter with wide stop band characteristics. As shown in FIG. 2, the miniaturized balanced low-pass filter with wide stop band characteristic of the application generates reflection zero points at two frequency points of 0GHz and 0.68GHz respectively under the excitation of differential mode signals, and has differential mode reflection coefficient |S ddAA The I is smaller than-18.8 dB in the frequency range of 0-0.78 GHz; in-band minimum differential mode transmission loss S of filter ddBA The I is-0.04 dB, the 3dB filter cutoff frequency of the low-pass filter is 1.12GHz, and the out-of-band rejection level of the differential mode signal is better than 20dB in the stop band range of 1.56-13.7 GHz. As shown in FIG. 3, a miniaturized balanced low-pass filter with wide stop band characteristics according to the present application suppresses common mode transmission under common mode signal excitationS is prepared ccBA The frequency is smaller than-40 dB in the whole frequency range of 0-13.7 GHz, and the common mode rejection capability is excellent. This shows that the miniaturized balanced low-pass filter with wide stop band characteristic of the application can well inhibit common mode noise and realize low-pass filter characteristic of high selectivity and wide stop band inhibition for differential mode signals.
In summary, the miniaturized balanced low-pass filter with wide stopband characteristic of the application can effectively inhibit common mode noise, and meanwhile, the input differential mode signal has the low-pass filter characteristics of high selectivity and wide stopband inhibition, and the filter has simple structure and small circuit size, thus being very suitable for various balanced microwave systems to improve the overall performance of the system.
The foregoing is only a preferred embodiment of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art, who is within the scope of the present application, should make equivalent substitutions or modifications according to the technical scheme of the present application and the inventive concept thereof, and should be covered by the scope of the present application.
Claims (4)
1. A miniaturized balanced low pass filter with wide stop band characteristics comprising: the double-sided parallel strip line input port A of the differential structure, the double-sided parallel strip line output port B of the differential structure, two groups of reversed phase connection structures, two sections of double-sided high-impedance transmission lines, two sections of double-sided open-ended harmonic suppression lines, two sections of double-sided low-impedance transmission lines, one section of double-sided parallel coupling line (13), one section of double-sided open-ended resonant line (14) and a dielectric plate (15);
the differential structure double-sided parallel strip line input port A comprises an input port A+ (1) and an input port A- (2);
the differential structure double-sided parallel strip line output port B comprises an output port B+ (3) and an output port B- (4);
the two groups of reverse phase connection structures comprise a reverse phase connection combination I (5) and a reverse phase connection combination II (6); one end of the reverse phase connection combination I (5) is connected with the input port A+ (1), and the other end of the reverse phase connection combination I is connected with the connection part of the input port A- (2) and the first double-sided high-impedance transmission line (7); one end of the reverse phase connection combination II (6) is connected with the output port B+ (3), and the other end of the reverse phase connection combination II is connected with the connection part of the output port B- (4) and the second double-sided high-impedance transmission line (8);
the two-section double-sided high-impedance transmission line comprises a first double-sided high-impedance transmission line (7) and a second double-sided high-impedance transmission line (8); one end of the first double-sided high-impedance transmission line (7) is connected with the input port A- (2), and the other end of the first double-sided open-ended harmonic suppression line (9) is connected with the connection part of the first double-sided low-impedance transmission line (11); one end of the second double-sided high-impedance transmission line (8) is connected with the output port B- (4), and the other end of the second double-sided open-ended harmonic suppression line (10) is connected with the connection part of the second double-sided low-impedance transmission line (12);
the two-section double-sided open-ended harmonic suppression line comprises a first double-sided open-ended harmonic suppression line (9) and a second double-sided open-ended harmonic suppression line (10); one end of the first double-sided open-ended harmonic suppression line (9) is connected to the joint of the first double-sided high-impedance transmission line (7) and the first double-sided low-impedance transmission line (11), and the other end of the first double-sided open-ended harmonic suppression line is open; one end of the second double-sided open-ended harmonic suppression line (10) is connected to the joint of the second double-sided high-impedance transmission line (8) and the first double-sided low-impedance transmission line (12), and the other end of the second double-sided open-ended harmonic suppression line is open;
the two-section double-sided low-impedance transmission line comprises a first double-sided low-impedance transmission line (11) and a second double-sided low-impedance transmission line (12); one end of the first double-sided low-impedance transmission line (11) is connected to the connection part of the first double-sided high-impedance transmission line (7) and the first double-sided open-ended harmonic suppression line (9), and the other end of the first double-sided low-impedance transmission line is connected with the double-sided parallel coupling line (13); one end of the second double-sided low-impedance transmission line (12) is connected to the connection part of the second double-sided high-impedance transmission line (8) and the second double-sided open-ended harmonic suppression line (10), and the other end of the second double-sided low-impedance transmission line is connected with the double-sided parallel coupling line (13);
an A port (1 a) of the double-sided parallel coupling line (13) is connected with a first double-sided low-impedance transmission line (11), a B port (1B) of the double-sided parallel coupling line (13) is connected with a second double-sided low-impedance transmission line (12), and a C port (1C) and a D port (1D) of the double-sided parallel coupling line (13) are connected with a double-sided open-ended resonant line (14).
2. A miniaturized balanced low pass filter with wide stop band characteristics according to claim 1 characterized in that: the common mode rejection characteristic of the balanced low-pass filter is adjusted by adjusting the inverse connection combination I (5) and the inverse connection combination II (6).
3. A miniaturized balanced low pass filter with wide stop band characteristics according to claim 1 characterized in that: the characteristic impedance and the electrical length of the first double-sided open-ended harmonic suppression line (9) and the second double-sided open-ended harmonic suppression line (10) are adjusted so as to realize the wide stop band suppression characteristic of the balanced low-pass filter.
4. A miniaturized balanced low pass filter with wide stop band characteristics according to claim 1 characterized in that: the passband bandwidth of the balanced low-pass filter is adjusted by adjusting the coupling coefficient of the double-sided parallel coupling lines (13).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311081444.8A CN117013222A (en) | 2023-08-25 | 2023-08-25 | Miniaturized balanced low-pass filter with wide stop band characteristic |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311081444.8A CN117013222A (en) | 2023-08-25 | 2023-08-25 | Miniaturized balanced low-pass filter with wide stop band characteristic |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117013222A true CN117013222A (en) | 2023-11-07 |
Family
ID=88572770
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311081444.8A Pending CN117013222A (en) | 2023-08-25 | 2023-08-25 | Miniaturized balanced low-pass filter with wide stop band characteristic |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117013222A (en) |
-
2023
- 2023-08-25 CN CN202311081444.8A patent/CN117013222A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111786062B (en) | Balanced/unbalanced power divider/combiner with unbalanced-end non-reflection filtering characteristic | |
| CN103367845B (en) | Ultra-wideband micro-strip balance filter | |
| CN109755702A (en) | A kind of four frequency differential bandpass filters | |
| CN116247406A (en) | Balance-unbalance power divider with broadband reflection-free filter characteristic | |
| CN113411063B (en) | Harmonic suppression matching circuit structure and power amplifier suitable for balun | |
| CN115333500A (en) | Non-reflection broadband band-pass filter with flat band and high frequency selectivity | |
| CN116995383A (en) | Balanced linear phase band-pass filter with differential mode non-reflection characteristic | |
| CN115149230B (en) | Balance ultra-wideband band-pass filter with harmonic suppression function | |
| CN116527009B (en) | Filter with electrical device and acoustic device mixed and radio frequency front end | |
| CN113346861A (en) | Bandwidth-adjustable reflection-free filter of full-open branch transmission line | |
| CN117254228A (en) | Reflection-free waveguide band-pass filter based on 3dB orthogonal coupler | |
| CN101702458A (en) | Ultra wide band filter with band-stop characteristic | |
| CN110459845A (en) | A kind of balanced type Double-band-pass microstrip filter | |
| CN116454573A (en) | Compact double-end absorption band-pass filter | |
| CN117013222A (en) | Miniaturized balanced low-pass filter with wide stop band characteristic | |
| CN115863940A (en) | Broadband balanced type notch filter with differential mode reflection-free characteristic | |
| CN213717939U (en) | IPD absorption type low-pass filter | |
| CN100574004C (en) | The annular coupler of compensation-type spiral micro-band resonance unit and formation thereof | |
| CN209046602U (en) | A kind of absorption-type low-pass filter | |
| CN203351719U (en) | Ultra wideband micro-strip balance filter | |
| CN213717938U (en) | IPD absorption type high-pass filter | |
| CN114843728B (en) | Balanced band-pass filter with input end having differential mode and common mode reflection-free characteristics | |
| CN118572333A (en) | Broadband high-isolation balanced/unbalanced filter cross device | |
| CN117374536A (en) | Balanced/unbalanced microstrip cross device with band-pass filtering function | |
| CN117438762A (en) | Low-loss balanced broadband switch filter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |