CN109510604B - Filter circuit applied to radio frequency front end - Google Patents
Filter circuit applied to radio frequency front end Download PDFInfo
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- CN109510604B CN109510604B CN201811348670.7A CN201811348670A CN109510604B CN 109510604 B CN109510604 B CN 109510604B CN 201811348670 A CN201811348670 A CN 201811348670A CN 109510604 B CN109510604 B CN 109510604B
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- filter circuit
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- 239000003990 capacitor Substances 0.000 claims abstract description 39
- 238000004519 manufacturing process Methods 0.000 claims description 34
- 238000000034 method Methods 0.000 claims description 19
- 239000004973 liquid crystal related substance Substances 0.000 claims description 6
- 239000000758 substrate Substances 0.000 claims description 5
- 239000000919 ceramic Substances 0.000 claims description 3
- 239000004065 semiconductor Substances 0.000 claims description 3
- 230000000295 complement effect Effects 0.000 claims description 2
- 229910044991 metal oxide Inorganic materials 0.000 claims description 2
- 150000004706 metal oxides Chemical class 0.000 claims description 2
- 230000001629 suppression Effects 0.000 description 8
- 238000010586 diagram Methods 0.000 description 5
- 238000012536 packaging technology Methods 0.000 description 5
- 238000001914 filtration Methods 0.000 description 4
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 3
- 229910052710 silicon Inorganic materials 0.000 description 3
- 239000010703 silicon Substances 0.000 description 3
- 238000004891 communication Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005538 encapsulation Methods 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 230000003321 amplification Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 238000004806 packaging method and process Methods 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H5/00—One-port networks comprising only passive electrical elements as network components
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- Filters And Equalizers (AREA)
Abstract
The application provides a filter circuit applied to a radio frequency front end, which comprises: the first capacitor, the second capacitor, the third capacitor, the first inductor, the second inductor and the third inductor. The first capacitor is connected with the first inductor to form a serial branch, the serial branch and the second capacitor form a first parallel branch, the input end of the first parallel branch is used as the input end of the filter circuit, and the output end of the first parallel branch is grounded through the second inductor. The third capacitor and the third inductor form a second parallel branch, the input end of the second parallel branch is connected with the input end of the first parallel branch, and the output end of the second parallel branch is used as the output end of the filter circuit.
Description
Technical Field
The application relates to the technical field of communication, in particular to a filter circuit applied to a radio frequency front end.
Background
The rf front end is a signal processing section in the communication system between the antenna and the baseband circuit, and transmits signals in the form of high-frequency ac. The radio frequency front end includes a transmit path and a receive path. The receiving path mainly comprises a low noise amplifier, a filter and the like, so that the useful radio frequency signal can be picked up from the antenna completely without distortion and is transmitted to a processing circuit of a subsequent stage. The filter has the effect of eliminating interference noise in the radio frequency front end, allows signals in a certain frequency range to pass through, and blocks or attenuates waves outside the working frequency band, so that the waves outside the working frequency band are effectively filtered. With the increasing application of rf front-end technology. Accordingly, the amount of filters applied to the rf front-end has also shown to increase rapidly. Among them, the acoustic filter is more prominent.
The acoustic filter adopts a piezoelectric-inverse piezoelectric material, and can realize the suppression of interference of a plurality of frequency points based on the conversion principle of acoustic-electric signals, but the production cost is increased, and the packaging technology is provided with higher requirements, and meanwhile, the integrated design with the low-noise amplifier is limited.
Therefore, under the condition of ensuring the cost and the packaging technical requirement, how to realize the suppression of interference of a plurality of frequency points by the filter applied to the radio frequency front end becomes a problem which needs to be solved by the person skilled in the art.
Disclosure of Invention
In view of this, the embodiment of the application provides a filter circuit applied to a radio frequency front end, so as to suppress interference of multiple frequency points under the requirements of guaranteed cost and packaging technology.
In order to achieve the above object, the embodiment of the present application provides the following technical solutions:
a filter circuit for use in a radio frequency front end, comprising: the first capacitor, the second capacitor, the third capacitor, the first inductor, the second inductor and the third inductor. Wherein, the liquid crystal display device comprises a liquid crystal display device,
the first capacitor is connected with the first inductor to form a serial branch, the serial branch and the second capacitor form a first parallel branch, the input end of the first parallel branch is used as the input end of the filter circuit, and the output end of the first parallel branch is grounded through the second inductor. The third capacitor and the third inductor form a second parallel branch, the input end of the second parallel branch is connected with the input end of the first parallel branch, and the output end of the second parallel branch is used as the output end of the filter circuit.
Optionally, the manufacturing process of the filter circuit requires that components be distributed in an integrated manner.
Optionally, the filter circuit fabrication process includes a low temperature co-fired Ceramic process (Low Temperature Co-fired Ceramic, LTCC).
Optionally, the filter circuit fabrication process includes an integrated passive device process (Integrated Passive Device, IPD).
Optionally, the filter circuit manufacturing process includes a laminate substrate manufacturing process.
Alternatively, the components required by the manufacturing process of the filter circuit may be distributed by patches.
Optionally, the filter circuit fabrication process includes a discrete device patch fabrication process.
Alternatively, the filter circuit fabrication process may be compatible with a complementary metal oxide semiconductor process (ComplementaryMetal Oxide Semiconductor, CMOS).
The filter circuit applied to the radio frequency front end provided by the application adopts fewer components, namely a capacitor and an inductor, so that the product cost is controlled, and higher encapsulation performance is ensured. And the first capacitor and the first inductor are connected to form a serial branch, and the serial branch and the second capacitor form a first parallel branch. The third capacitor and the third inductor form a second parallel branch, so that the interference of a plurality of frequency points is restrained, and finally the interference of the plurality of frequency points can be restrained under the requirements of the guaranteed cost and the packaging technology.
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 embodiments of the present application, and that other drawings can be obtained according to the provided drawings without inventive effort for a person skilled in the art.
Fig. 1 is a schematic diagram of a filter circuit applied to a radio frequency front end according to an embodiment of the present application;
fig. 2 is a frequency response diagram of a first parallel branch of a filter circuit applied to a radio frequency front end according to an embodiment of the present application;
fig. 3 is a frequency response diagram of a first parallel branch and a second inductor of a filter circuit applied to a radio frequency front end according to an embodiment of the present application;
fig. 4 is a frequency response diagram of a second parallel branch of a filter circuit applied to a radio frequency front end according to an embodiment of the present application;
fig. 5 is a frequency response diagram of a filter circuit applied to a radio frequency front end according to an embodiment of the present application.
Detailed Description
The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only 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 embodiment of the application provides a filter circuit applied to a radio frequency front end, which is used for inhibiting interference of a plurality of frequency points under the requirements of guaranteeing cost and packaging technology.
Referring to fig. 1, a filter circuit for a radio frequency front end according to an embodiment of the present application includes:
the first capacitor C1, the second capacitor C2, the third capacitor C3, the first inductor L1, the second inductor L2 and the third inductor L3. Wherein, the liquid crystal display device comprises a liquid crystal display device,
the first capacitor C1 and the first inductor L1 are connected to form a series branch, the series branch and the second capacitor C2 form a first parallel branch, the input end of the first parallel branch is used as the input end of the filter circuit, and the output end of the first parallel branch is grounded through the second inductor L2. The third capacitor C3 and the third inductor L3 form a second parallel branch, the input end of the second parallel branch is connected with the input end of the first parallel branch, and the output end is used as the output end of the filter circuit.
Referring to fig. 2, the first capacitor C1 and the first inductor L1 resonate at a frequency point f1 to have a low stop band resistance characteristic, signals of the frequency point are filtered, and signals of other frequency points can pass through, so that filtering of interference signals of the first frequency point is realized. The passband width and the in-band suppression are related to the first inductance L1 quality factor.
Also referring to fig. 2, the series branch of the first capacitor C1 and the first inductor L1 and the second capacitor C2 resonate in parallel at a frequency point f2, and a signal of the frequency point can pass through the high stop band characteristic.
The first parallel branch circuit has a capacitance characteristic at a frequency point higher than f2, and the equivalent capacitance value is Cp ', and Cp' and the second inductor L2 resonate at a frequency point f4, as shown in fig. 3. The frequency point f4 has low stop band resistance, the signals of the frequency point are filtered, and the signals of other frequency points can pass through, so that the filtering of the interference signals of the second frequency point is realized. The stop band width and the in-band suppression degree are related to the quality factors of the second inductor L2 and the first inductor L1.
As shown in fig. 4, the third capacitor C3, the third inductor L3 and the input capacitor of the low noise amplifier resonate together at a frequency point f3 to form a high stop band resistance characteristic, signals of the frequency point are filtered, and signals of other frequency points can pass through, so that the filtering of interference signals of the third frequency point is realized. And matching the characteristic impedance of the low-noise amplifier to the working characteristic impedance of the system at the frequency points except the f3 frequency point, so as to realize in-band matching and out-of-band suppression. The stop band width, in-band suppression of the second parallel branch is related to the inductance quality factor of the third inductance L3.
The filter circuit applied to the radio frequency front end provided by the application adopts fewer components, namely a capacitor and an inductor, so that the product cost is controlled, and higher encapsulation performance is ensured. And the first capacitor and the first inductor are connected to form a serial branch, and the serial branch and the second capacitor form a first parallel branch. The third capacitor and the third inductor form a second parallel branch, so that the interference of a plurality of frequency points is restrained, and finally the interference of the plurality of frequency points can be restrained under the requirements of the guaranteed cost and the packaging technology.
It should be noted that, referring to fig. 5, the filter circuit applied to the rf front end provided by the present application can suppress the interference of the three frequency points f1, f3 and f4, and allow the signal near the frequency point f2 to pass through. The frequency band near the f2 frequency point is the working frequency band of the filter circuit. At the f2 frequency point in the working frequency band, the frequency response characteristic of the filter circuit reaches a peak value, which represents the maximum power gain. f1, f3 and f4 frequency points are low frequency response characteristic points and represent power suppression points. In addition, the filter itself does not have a function of signal amplification in all frequency bands, so that the entire frequency response characteristic is below the X-axis, indicating that the frequency response characteristic is negative.
Alternatively, in another embodiment of the present application, the manufacturing process of the filter circuit of the present application requires components to be integrally distributed on the manufacturing carrier to implement the filter circuit. I.e. a filter circuit can be integrated by winding the inductor and arranging the capacitor on the manufacturing carrier.
Alternatively, in another embodiment of the present application, the manufacturing process of the filter circuit of the present application includes LTCC. LTCC can enable the fabrication of carrier self-inductance and capacitance.
Alternatively, in another embodiment of the present application, the manufacturing process of the filter circuit of the present application comprises IPD. IPD is to wire an inductor and set a capacitor on a high-resistance silicon wafer to implement a filter circuit. The high-resistance silicon wafer is wound with the wire inductance so that the filter circuit has a higher inductance quality factor, and the stop band width and the in-band suppression degree of the filter circuit can be adjusted accordingly. Typically IPD is limited in silicon die to distributed inductance and capacitance.
Alternatively, in another embodiment of the present application, the manufacturing process of the filter circuit of the present application includes a laminated substrate manufacturing process. The laminated substrate manufacturing process can realize the manufacture of carrier self-inductance and capacitance.
Optionally, in another embodiment of the present application, the manufacturing process of the filter circuit of the present application requires components to implement the effect of impurity removal and filtering in a surface patch manner in the application scenario circuit.
Alternatively, in another embodiment of the present application, the manufacturing process of the filter circuit of the present application includes a manufacturing process of a discrete device patch.
Alternatively, in another embodiment of the present application, the filter circuit of the present application is fabricated with a CMOS compatible process. Among them, the manufacturing process of the filter circuit compatible with CMOS includes LTCC, IPD, laminated substrate manufacturing process. Based on the compatibility of the manufacturing process of the filter circuit and the CMOS, the filter circuit and the application circuit of the CMOS can adopt the same manufacturing carrier, so that the integration level of the filter circuit and the application circuit of the CMOS is improved, and the filter circuit and the application circuit of the CMOS are integrated.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (8)
1. A filter circuit for use in a radio frequency front end, comprising: the first capacitor, the second capacitor, the third capacitor, the first inductor, the second inductor and the third inductor; wherein, the liquid crystal display device comprises a liquid crystal display device,
the first capacitor is connected with the first inductor to form a serial branch, the serial branch and the second capacitor form a first parallel branch, the input end of the first parallel branch is used as the input end of the filter circuit, and the output end of the first parallel branch is grounded through the second inductor; the third capacitor and the third inductor form a second parallel branch, the input end of the second parallel branch is connected with the input end of the first parallel branch, and the output end of the second parallel branch is used as the output end of the filter circuit.
2. The filter circuit for use in a radio frequency front end of claim 1, wherein the filter circuit is fabricated with a process requiring components to be distributed in an integrated manner.
3. The filter circuit for use in a radio frequency front end of claim 2, wherein the filter circuit fabrication process comprises a low temperature co-fired ceramic process LTCC.
4. The filter circuit for a radio frequency front end of claim 2, wherein the filter circuit fabrication process comprises an integrated passive device process IPD.
5. The filter circuit for use in a radio frequency front end of claim 2, wherein the filter circuit fabrication process comprises a laminate substrate fabrication process.
6. The filter circuit for use in a rf front-end of claim 1, wherein the manufacturing process of the filter circuit for use in a rf front-end requires components to be distributed using patches.
7. The filter circuit for a radio frequency front end of claim 6, wherein the filter circuit fabrication process comprises a discrete device patch fabrication process.
8. A filter circuit for use in a radio frequency front end as claimed in any of claims 1 to 5, wherein the filter circuit is fabricated with complementary metal oxide semiconductor process CMOS compatible.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811348670.7A CN109510604B (en) | 2018-11-13 | 2018-11-13 | Filter circuit applied to radio frequency front end |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811348670.7A CN109510604B (en) | 2018-11-13 | 2018-11-13 | Filter circuit applied to radio frequency front end |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109510604A CN109510604A (en) | 2019-03-22 |
| CN109510604B true CN109510604B (en) | 2023-10-13 |
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| CN201811348670.7A Active CN109510604B (en) | 2018-11-13 | 2018-11-13 | Filter circuit applied to radio frequency front end |
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Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08237061A (en) * | 1995-02-28 | 1996-09-13 | Tokyo Tsuuki:Kk | Low pass filter |
| CN1369965A (en) * | 2001-02-07 | 2002-09-18 | 株式会社村田制作所 | Elastic surface wave filtering device |
| JP2003008385A (en) * | 2001-06-18 | 2003-01-10 | Murata Mfg Co Ltd | Composite lc filter circuit and composite lc filter component |
| CN101164228A (en) * | 2005-04-20 | 2008-04-16 | Nxp股份有限公司 | A parallel arranged linear amplifier and dc-dc converter |
| CN101277056A (en) * | 2007-03-30 | 2008-10-01 | 艾默生网络能源系统有限公司 | Filter circuit |
| CN101789796A (en) * | 2009-08-10 | 2010-07-28 | 上海闻泰电子科技有限公司 | Filter circuit for inhibiting harmonic signal of mobile terminal and method therefor |
| CN102881981A (en) * | 2012-08-31 | 2013-01-16 | 华南理工大学 | Lumped element power divider integrated with band-pass filtering function |
| CN103138705A (en) * | 2011-12-01 | 2013-06-05 | 西安电子科技大学 | Band-pass filter |
| CN103545582A (en) * | 2012-07-10 | 2014-01-29 | 南京理工大学 | UWB (ultra wide band) band-pass filter |
| CN206461069U (en) * | 2017-02-13 | 2017-09-01 | 石家庄创天电子科技有限公司 | A kind of many transmission zero wave filters |
| CN108736909A (en) * | 2018-05-09 | 2018-11-02 | 深圳市盛路物联通讯技术有限公司 | The radio circuit and terminal of SAW filter combination anti aliasing purposes filter |
| CN208971478U (en) * | 2018-11-13 | 2019-06-11 | 上海艾为电子技术股份有限公司 | A kind of filter circuit applied to radio-frequency front-end |
-
2018
- 2018-11-13 CN CN201811348670.7A patent/CN109510604B/en active Active
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08237061A (en) * | 1995-02-28 | 1996-09-13 | Tokyo Tsuuki:Kk | Low pass filter |
| CN1369965A (en) * | 2001-02-07 | 2002-09-18 | 株式会社村田制作所 | Elastic surface wave filtering device |
| JP2003008385A (en) * | 2001-06-18 | 2003-01-10 | Murata Mfg Co Ltd | Composite lc filter circuit and composite lc filter component |
| CN101164228A (en) * | 2005-04-20 | 2008-04-16 | Nxp股份有限公司 | A parallel arranged linear amplifier and dc-dc converter |
| CN101277056A (en) * | 2007-03-30 | 2008-10-01 | 艾默生网络能源系统有限公司 | Filter circuit |
| CN101789796A (en) * | 2009-08-10 | 2010-07-28 | 上海闻泰电子科技有限公司 | Filter circuit for inhibiting harmonic signal of mobile terminal and method therefor |
| CN103138705A (en) * | 2011-12-01 | 2013-06-05 | 西安电子科技大学 | Band-pass filter |
| CN103545582A (en) * | 2012-07-10 | 2014-01-29 | 南京理工大学 | UWB (ultra wide band) band-pass filter |
| CN102881981A (en) * | 2012-08-31 | 2013-01-16 | 华南理工大学 | Lumped element power divider integrated with band-pass filtering function |
| CN206461069U (en) * | 2017-02-13 | 2017-09-01 | 石家庄创天电子科技有限公司 | A kind of many transmission zero wave filters |
| CN108736909A (en) * | 2018-05-09 | 2018-11-02 | 深圳市盛路物联通讯技术有限公司 | The radio circuit and terminal of SAW filter combination anti aliasing purposes filter |
| CN208971478U (en) * | 2018-11-13 | 2019-06-11 | 上海艾为电子技术股份有限公司 | A kind of filter circuit applied to radio-frequency front-end |
Non-Patent Citations (2)
| Title |
|---|
| Fully integrated low-noise-amplifier with high quality factor L-C filter for 1.8 GHz wireless applications;L. Fanucci;ISCAS 2001. The 2001 IEEE International Symposium on Circuits and Systems;全文 * |
| 应用于 WLAN的低噪声放大器设计及射频收发前端集成;刘祖华;中国优秀硕士学位论文全文数据库;全文 * |
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| CN109510604A (en) | 2019-03-22 |
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Address after: Room 1201, No.2, Lane 908, Xiuwen Road, Minhang District, Shanghai, 201199 Patentee after: SHANGHAI AWINIC TECHNOLOGY Co.,Ltd. Country or region after: China Address before: Room 303-39, building 33, 680 Guiping Road, Xuhui District, Shanghai 200233 Patentee before: SHANGHAI AWINIC TECHNOLOGY Co.,Ltd. Country or region before: China |